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The Bulletinof

The British Society for Cardiovascular ResearchRegistered Charity Number: 1011141

Vol. 25 No. 1January 2012

www.bscr.org

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The BulletinThe Publication of The British Society for Cardiovascular Research

EditorsDr Nicola Smart

UCL Institute of Child Health30 Guilford Street

London WC1N 1EHTel.: 020 7905 2114 Fax: 020 7404 6191

E-mail: [email protected]

Dr Melanie MadhaniSchool of Clinical and Experimental Medicine

The Medical School, Vincent DriveThe University of Birmingham

BirminghamB15 2TT

Tel: 0121 4144042E-mail: [email protected]

ChairDr. M. Yvonne Alexander

School of Clinical & Lab. Sciences,University of Manchester,

46 Grafton StManchester. M13 9NT

Tel: +44 (0) 161 2751224 Fax: +44 (0) 161 2751183


SecretaryDr Chris Jackson

Bristol Heart Institute, University of BristolLevel 7, Bristol Royal Infirmary

Bristol BS2 8HW.Tel/Fax: 0117 928 2534


Tr easurerDr Michael J. Curtis

Cardiovascular ResearchRayne Institute, St. Thomas’ Hospital

London SE1 7EHTel.: 020 7188 1095 Fax: 020 7188 3902


CommitteeProfessor Colin Berry

Institute of Cardiovascular and Medical Sciences126 University Place, University of Glasgow

Glasgow G12 8TATel: 0141 330 5056 Fax 0141 330 2522


Dr Samuel BoatengInstitute of Cardiovascular and Metabolic Research,

Hopkins Building, Whiteknights campusUniversity of Reading Reading RG66UB

Tel: 01183787041 Fax: 01183784703E-mail: [email protected]

Dr Carolyn CarrCardiac Metabolism Research Group

Department of Physiology, Anatomy and Genetics,Sherrington Building Parks Road Oxford

OX1 3PTTel: 01865 282247 Fax 01865 282272E-mail: [email protected]

Professor Barbara CasadeiUniversity Department of Cardiovascular Medicine

John Radcliffe HospitalOxford OX3 9DU

Tel: 01865 220132 Fax: 01865 768844E-mail: [email protected]

Dr Sean DavidsonThe Hatter Cardiovascular Institute

University College London67 Chenies Mews, London WC1E 6HXTel: 0207 380 9376 Fax: 0207 380 9505

Email: [email protected]

Dr Andrew GraceSection of Cardiovascular Biology

Department of Biochemistry, University of CambridgeTennis Court Road, Cambridge CB2 1QW

Tel: 01223 333631 Fax: 01223 333345E-mail: [email protected]

Dr David GrieveCentre for Vision and Vascular Science

Queen’s University BelfastInstitute of Clinical Science Block A

Grosvenor RoadBelfast BT12 6BA

Tel: 028 9063 5013 Fax: 028 9097 2699E-mail: [email protected]

Dr Derek HausenloyThe Hatter Cardiovascular Institute,

University College London67 Chenies Mews, London WC1E 6HXTel: 0207 380 9894 Fax: 0207 380 9505


Dr Richard HeadsDept of Cardiology

The Rayne Institute, St Thomas’ HospitalLambeth Palace Rd, London SE1 7EH

Tel: 020 7188 0966 Fax: 020 7188 0970E-mail: [email protected]

Dr Cathy HoltDivision of Cardiovascular and Endocrine Sciences

University of Manchester3.31b Core Technology Facility

46 Grafton Street, Manchester M13 9NTTel: 0161 275 5671 Fax: 0161 275 1183


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Editorial 3

Review: "Vascular Smooth Muscle Cells: Phenotype and Function in Type 2 Diabetes"by Karen E. Porter and Kirsten Riches 4

Secretary's Column 13

A Letter from Our New Chair, Dr Yvonne Alexander 14

Report by Marshall Research Excellence Prize Winner by Dr Joseph C. Wu 15

Report by Marshall Young Investigator Prize Winner by Dr Joseph R. Burgoyne 21

Forthcoming Cardiovascular Meetings 25

BSCR Late Spring 2012 Meeting with BAS at the BCS: Full Programme 26

BSCR Autumn Meeting "Novel Insights into the Pathogenesis of Cardiac Remodeling" 29

British Heart Foundation Grants 31

Cardiovascular Related Wellcome Trust grants 32

BSCR Late Spring 2012 Meeting with BAS/BCS 33

Editorial

Nicola Smart and Melanie Madhani

Cover artwork copyright Anthony Wright, 1997Cover design copyright Siân Rees and Anthony Wright, 1997

Contents

Welcome to the January 2012 issue of The Bul-letin and our best wishes for the New Year!

In this issue we bring you an elegant review,written by Karen Porter and Kirsten Riches of theUniversity of Leeds, which outlines the phenotypicchanges induced in vascular smooth muscle cells intype 2 diabetes. The authors provide an insight intothe mechanisms that underlie these phenotypic andfunctional alterations, which significantly contributetowards cardiovascular disease in diabetic patients,and discuss potential interventional strategies.

The new year brings a new BSCR Chair. DrYvonne Alexander of the University of Manchester,is our new leader. We're delighted to include a let-ter from Yvonne in which she offers her views onhow the BSCR is developing and invites suggestionsfor the future progression of the Society. We would

like to echo Yvonne's sentiments, and those of ChrisJackson, in his Column, by expressing our thanksand appreciation to our retiring Chair, ChrisNewman. It has been a pleasure working with Chrisand we wish him well.

This issue features two additional outstandingarticles, written by the recent winners of the Bernardand Joan Marshall prizes. Dr Joseph Wu, winner ofthe Research Excellence Award, describes the ob-stacles that currently stand in the way of translatingthe remarkable potential of iPS cell technology intohuman therapies. Dr Joseph Burgoyne, Young In-vestigator prize winner, provides a fascinating insightinto how protein modification, as a consequence ofobesity, contributes towards endothelial dysfunction.Having the name Joseph is not an entry requirementfor these prizes but it clearly helps!

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Vascular Smooth Muscle Cells: Phenotype andFunction in Type 2 Diabetes

by Karen E. Porter and Kirsten Riches

Division of Cardiovascular and Neuronal Remodelling, Leeds Institute of

Genetics, Health and Therapeutics (LIGHT), University of Leeds LS2 9JT.

Intr oduction - Prevalence of Type 2 Diabetes andCardiovascular Risk

Insulin resistance leading to type 2 diabetes(T2DM) is a chronic metabolic and inflammatorycondition [1]. Although initially symptomless and likelypresent for years, in the long term T2DM is associatedwith debilitating cardiovascular complications andpremature death; indeed, up to half of patients haveevidence of cardiovascular complications by the timediabetes is diagnosed [2]. In the UK alone, the numberof people diagnosed with T2DM has increased from1.4 million in 1996 to 2.9 million in 2011(diabetes.org.uk), with an inevitable impact onhealthcare costs reportedly accounting for £9 billion perannum - approximately 10% of the entire NHS budget.These alarming figures are attributable not only to anageing population but importantly to the rising epidemicof obesity and physical inactivity.

T2DM predisposes to pathologies of bothmicrovascular and macrovascular origin. Microvascular(principally retinopathy, nephropathy) and neuropathiccomplications can, to a significant degree, be retardedby early, intensive control of hyperglycaemia by insulinor oral therapies (reviewed recently in [3]).Macrovascular pathologies are numerous and coronaryartery disease (CAD) is common, regularly manifestingitself earlier in life than in individuals without diabetes[4]. The accelerated progression of atherosclerosispredisposes to myocardial ischaemia, infarction andstroke [5]. Peripheral arterial disease leads to criticallimb ischaemia and, together with impaired capacity todevelop collateral vessels in T2DM increases the riskof lower limb amputations. [6]. In addition, bothcoronary and peripheral revascularisation proceduresin patients with diabetes are problematic and the long-term outcomes are disappointing [7,8].

Glycaemic control and vascular complicationsIndividuals with insulin resistance and T2DM

generally have coexistent conditions of hyperglycaemiaand hyperlipidaemia together with hypercoagulabletendency, all of which impart vulnerability tocomplications [7]. Plasma levels of glycatedhaemoglobin (HbA1c) provide a marker of averageblood glucose levels over 8-12 weeks; in healthyindividuals this is typically 4.0 - 6.0%. In addition tobeing a diagnostic indicator of diabetes, HbA1c servesas a marker of glycaemic control in individuals withestablished diabetes. Current guidelines suggest that inT2DM patients HbA1c is ideally maintainedtherapeutically by insulin and/or oral therapies < 7.0%[3]. However, although the DCCT and UKPDS studiesdemonstrated this approach to be effective in retardingand preventing microvascular complications [3], thebeneficial effects on macrovascular complications wereless apparent, at least in the medium-term. Indeed, theADVANCE, VADT and ACCORD trials reported thatintensive glycaemic treatment had little, if any, additionalbenefit in patients with diabetes and clinical CAD [3,9].Development of vascular complications as a result ofprior exposure to hyperinsulinaemia andhyperglycaemia appears to confer a persistent alterationof vascular gene expression that is referred to asmetabolic memory (reviewed in [10]). This is upheldby results from the UKPDS study that termed thisphenomenon as a “legacy” effect [11].

Endothelial Dysfunction in T2DM

The vascular manifestations associated withT2DM can be attributed to dysfunction of the cellularcomponents of the vasculature in a complex responseto environmental stimuli [12]; the endothelium andsmooth muscle cells (SMC) being key players. In

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health, the endothelium plays a central role in vesselwall homeostasis by synthesising a critical balance ofvasodilators (of which nitric oxide (NO) is essential),and vasoconstrictors such as angiotensin II, endothelin-1 and reactive oxygen species (ROS). NO generationin endothelial cells (EC) is dependent on intact insulinsignalling through the phosphoinositide 3-kinase (PI3-K) /Akt pathway [13], and, as such, exerts beneficialvasorelaxant, anti-inflammatory and antioxidant effectson the vasculature. NO production maintains bloodpressure within physiological ranges through promotingrelaxation of medial SMC lying beneath the endothelium.Endothelial dysfunction, a common early event in insulinresistance (“pre-diabetes”) and T2DM, ischaracterised by a range of abnormalities, the mostextensively studied being decreased NO synthesis(reviewed in [14]). In these circumstances,atherosclerosis is accelerated, blood pressure iselevated and a paradoxical coronary vasoconstrictionoccurs. Indeed, reduced NO bioavailability is observedprior to the onset of atherosclerotic structural changesand has been shown to predict the development ofcoronary artery disease [15] and future cardiovascularevents [16].

The central role of the endothelium in vascularhealth and disease is an active and ongoing area ofresearch. By contrast, the vascular SMC is less wellstudied; the aim of this review is to discuss currentunderstanding of vascular SMC function and dysfunctionin diabetes, and identify potential targets for intervention.

Critical role of smooth muscle cells in vascularhomeostasis and remodelling

Vascular SMC of blood vessel walls exhibitremarkable plasticity, switching between differentiatedand dedifferentiated phenotypes in response to changesin the local environment (reviewed in [17]). Asdescribed above, healthy endothelium maintains apredominant differentiated “contractile” SMCphenotype that regulates vascular structure and tone.Conversely, de-differentiated “synthetic” SMC aresusceptible to proatherosclerotic stimuli throughfunctional responses such as proliferation and migrationas opposed to the early senescence and apoptosis thatbefalls EC. Within the vasculature the proportions ofcontractile and secretory SMC are reported to vary,with the presence of distinct subpopulations that mayhave implications for arterial disease [18]. Therefore,whilst phenotypic modulation is vital to embryogenesis,vascular adaptation, remodelling and repair, it also

augments progression of vascular diseases such asatherosclerosis, hypertension, restenosis and bypassgraft failure [17]. The ability of SMC to retain plasticityand respond appropriately (largely through changes inproliferation and migration) is therefore critical in thisrespect.

Markers of SMC Phenotype

Switching of SMC between the differentiated anddedifferentiated state is regulated by a variety ofenvironmental stimuli, and dedifferentiation isaccompanied by loss of SMC-specific marker genessuch as α-smooth muscle actin (α-SMA), smoothmuscle myosin heavy chain (SM-MHC), smooth muscle22α (SM22α) and desmin, paralleled by increases insynthetic gene expression (reviewed in [17]). SMCmarker genes are regulated by CArG box motifs withintheir promoters which are bound by serum-responsefactor (SRF) and myocardin to induce their expression.Kruppel-like factor-4 (KLF4), a key transcriptionfactor in SMC switching, can reduce the expression ofmyocardin leading to a reduction in SMC marker geneexpression and a synthetic phenotype [19]. Modulatingfactors include platelet-derived growth factor BB(PDGF) which promotes dedifferentiation [19] andtransforming growth factor beta (TGFβ) whichpromotes differentiation [20] (Figure 1).

Marker Gene

Expressione.g. SM-MHC, Desmin

↓ α-SMA

− β-actin

↑ Proliferation

Dedifferentiation

↑ α-SMA

↓ β-actin

↑ Stress fibres

Differentiation

e.g. PDGF e.g. TGFβ

SRFMyocardinKLF4

Figure 1: SMC marker gene expression controls thedifferentiation state. Serum response factor (SRF) bindsto the promoters of marker genes (e.g. smooth musclemyosin heavy chain (SM-MHC), desmin) promotingdifferentiation. Kruppel-like factor 4 (KLF4) can reduceexpression of the SRF-cofactor myocardin, promotingdedifferentiation.

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Differentiated SMC exhibit a highly organisedcytoskeleton with defined f-actin filaments that maintaincontractile function. Stress fibre formation is promotedby binding of the accessory protein SM22α to actinfilaments, inducing bundling and cell contractility. Incontrast, dedifferentiated proliferative SMC have aloose f-actin network [21]. Adoption of a syntheticphenotype is characteristic of a number ofcardiovascular disorders, and laboratory research hasbeen facilitated by the ability of SMC in culture tospontaneously acquire this phenotype [22]. This isaccompanied by altered SMA isoform expression,namely reduced α-SMA content and fibres, andincreased non-muscle α-actin [23].

Vascular SMC Proliferation and Migration –Response to Insulin and Glucose

The natural history of insulin resistance andT2DM can progress for a decade or more prior todiagnosis [24]. During this time, metabolic aberrancies,particularly hyperglycaemia and hyperinsulinaemia, canexert direct effects on all cell types in the vessel wall,inflicting detrimental changes in phenotype and functionand acceleration of the atherosclerotic process. Forexample, vascular SMC are known to be responsiveto the growth-stimulatory effects of insulin and insulin-like growth factors (IGF). Insulin induced primate aorticSMC proliferation in a concentration-dependentmanner in serum-supplemented medium over a periodof up to 10 days [25]. Similarly, insulin inducedproliferation of human arterial SMC [26], an effect thatwas later proposed to be due to insulin-stimulatedrelease of IGF-1 [27]. Another study showed amitogenic effect of IGF-1 itself on human aortic SMC(measured by 3[H] thymidine incorporation) albeit withlower potency than PDGF, a “classical” SMC mitogen[28]. In our own studies, and in agreement withprevious reports, we discovered that supplementationof SMC cultures with insulin increased saphenous vein(SV)-SMC proliferation concentration-dependently yetinterestingly, internal mammary artery (IMA)-SMCcultured from the same patients were entirely resistantto insulin’s growth-promoting effects [29]. Theautologous SV is routinely used to revascularisediseased coronary vessels and, although the IMA isproven to be a more robust conduit, its use is limitedby availability. SV patency rates are generally poorerthan IMA grafts, and significantly inferior in the diabeticpopulation, yet interestingly, IMA patency rates arecomparable in both ND and T2DM patients [30,31].

Clearly the pathogenesis of graft intimal hyperplasia ismultifactorial; however the apparent lack of mitogeniceffect of insulin on IMA-SMC may offer an explanationfor the superior patency rates of IMA grafts, even indiabetic patients.

In addition to insulin, glucose has been reportedto increase proliferation of cultured human infragenicularSMC and together they are synergistic [32]. Some otherstudies have reported a growth-promoting effect of highglucose alone on vascular SMC from human aorta andumbilical artery (25 mM) [33], and rat aorta (20 mM)[34,35]. A separate study reported that glucose-inducedaccelerated SMC proliferation was attributable todownregulation of protein kinase C [36]. In contrast,our own studies using SMC cultured from multiplepatients under conditions of normal (5.5mM) andelevated (25mM) glucose, did not detect any growth-modulating properties of glucose itself in cells of eithernon-diabetic or T2DM origin [37].

As well as its demonstrable effects onproliferation, insulin can influence SMC migration. Inbovine aortic SMC, insulin promoted migration that wasmediated via mitogen activated protein kinase (MAPK)signalling [38]. In our laboratory, we demonstrated thatinsulin promoted chemotaxis of human SV-SMC[29,37]. Interestingly, in a separate study we observedthat cells of diabetic origin consistently exhibited highermigratory capacities than those of non-diabetic originwhen maintained in the presence of insulin [37]. It istempting to speculate that in the diabetic state theperceived “beneficial” effects of insulin signalling viaPI3-K are impaired, whilst the “detrimental”(proatherogenic, pro-restenosis) pathways maypredominate via preserved MAPK signalling. It ispossible therefore that treatment with exogenous insulinin T2DM patients may exacerbate their alreadyincreased susceptibility to cardiovascular diseasethrough its actions on SMC.

Studies into SMC phenotype and function inT2DM

Animal Models of Diabetes

The human predisposition towardsatherosclerosis in T2DM is mirrored in streptozotocin(STZ)-induced diabetes in a murine model [39] andimportantly, the apparent inefficiency of glycaemicrestoration to reduce the cardiovascular risk reportedin human studies is also recapitulated in mice, suggestiveof a similar mechanism [40].

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Aortic SMC from STZ-induced diabetes in ratsare inherently more proliferative and dedifferentiatedcompared to their non-diabetic (ND) counterparts[23,41]. The enhanced proliferative capacity of thesecells was attributed to an increase in PDGF β receptordensity, and hence a greater response to the mitogenicactions of PDGF [41]. Those cells also exhibited greatercytoplasmic spread and a reduction in α-SMA stressfibres due to an absolute decrease in α-SMA proteinwithin the cell. In addition, the time-period of the switchfrom α-SMA to β-actin was shown to occur morerapidly in the cells from diabetic animals, perhapsindicating a greater susceptibility than ND SMC [23].The increase in proliferative capacity of aortic SMCfrom diabetic rats is also evident in SMC from alloxan(ALX)-induced diabetic rabbits, both being moreproliferative than SMC from their ND counterparts [41].

Some reports have utilised the db/db mouse asa model of diabetes and have observed increasedinflammatory gene expression, retained through severalpassages, in aortic SMC cultured from diabetic mousecompared to non-diabetic db/+ SMC [42,43]. Whilstanimal models of diabetes are informative, none directlyemulate the environment that mediates progressiveT2DM in humans.

Human StudiesNumerous in vitro studies have been performed

using tissue from T2DM and ND patients. T2DM SMCappear morphologically distinct from those of NDvessels. Both arterial and venous SMC cultured fromT2DM patients lack the typical hill-and-valley, spindle-shaped phenotype and adopt a more rhomboidphenotype [37,44]. Rhomboid morphology isreportedly characteristic of dedifferentiated, proliferativeSMC that are prevalent in vascular neointimal lesions[18], which correlates with observations previouslyreported in diabetic animal models [23,41]. In addition,SV-SMC from the T2DM patients exhibit a markeddisorganisation of the f-actin cytoskeleton (Figure 2),which can be mimicked in ND cells by Rho kinase(ROCK) inhibition indicating the involvement of theRhoA/ROCK signalling pathway [37]. Altered RhoA/ROCK signalling is well-known to have negative effectson the vasculature; inhibition of ROCK suppressesneointimal formation in balloon-injured rat arteries [45].

Concordant with rhomboid SMC being moreproliferative, arterial SMC from T2DM patients exhibitan increased proliferative capacity compared to theirND counterparts [44,46]. Interestingly, conditionedmedia from T2DM SMC was able to promote theproliferation of ND SMC, suggesting that the increased

ND

T2

DM

Vinculin F-actin Figure 2: Immunocytochemistry ofSMC from non-diabetic (ND) andT2DM patients. As described by Madiet al. (Ref.37), SMC from ND patientsdisplay small vinculin-positive focaladhesions and an organised f-actincytoskeleton with long fibrestraversing the cell. In contrast, SMCfrom T2DM patients have larger,denser focal adhesions with adisorganised f-actin cytoskeletoncharacterised by truncated fibres.Green = vinculin, blue = DAPI nuclearstain, red = F-actin, scale bar = 20 µm.

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proliferation observed in T2DM arterial SMC isdependent on a mitogenic factor secreted from the cellsthemselves [46]. A more recent study demonstratedenhanced rate of cell cycle entry in arterial SMC frompatients with T2DM together with increased basalphosphorylation of p38 and ERK1/2 [47], signallingpathways that are associated with cell proliferation.Enhanced proliferation has also been observed in SMCfrom both arterial (infragenicular) and venous (SV)sources [44].

Conversely, our own studies revealedconsistently lower proliferation in T2DM SV-SMC thanin ND cells paralleled by no detectable differences inERK phosphorylation between the two patientpopulations [37]. The disparities on SV-SMCproliferation may be due to a number of factors includingexperimental design, passage number and methodologyemployed to quantify proliferation (total DNAfluorescence microscopy versus direct cell counting).Importantly, it is known that SMC cultured fromdifferent vascular beds are known to have intrinsicallydifferent proliferative capacities [48].

Tissue rigidity is commonly reported in T2DMindividuals [49] and accordingly we have discoveredthat SV-SMC from T2DM patients exhibit increasednumbers of large, vinculin-positive focal adhesions(Figure 2). Increased propensity to form focaladhesions is associated with both cell stiffness andadhesion and is reportedly more prevalent in rhomboidSMC [37,50,51]. Accordingly, studies using arterial andvenous SMC have reported increased adhesion inT2DM-derived cells [44].

The composition of the extracellular matrix thatis predominantly regulated by SMC, also impacts ontissue flexibility. Studies on intact IMA specimens ofT2DM patients revealed a decrease in matrix-degradingmetalloproteinases MMP-1 and MMP-3, together withincreased extracellular matrix deposition [47]. Earlierstudies by the same group revealed a decrease in Aktphosphorylation, reduced NO production andincreased vasoconstriction in similar specimens [52]. Itis important to note that both of these studies wereconducted on intact arterial tissue and not individualcell types. Whilst the reduction in NO is likely to beattributable to endothelial dysfunction, andvasoconstriction assigned to altered SMC function, itis difficult overall to assign discrete cell signalling eventsand functional outcomes to a specific cell-type.

Studies of SMC migration from arterial andvenous sources revealed that those from T2DM had alarger response to PDGF than ND cells [44]. However,

this observation was not supported in our studies ofsolely SV-SMC which again may be due to differencesin experimental protocol. Arterial SMC from rats withSTZ-induced diabetes are reportedly more responsiveto PDGF due to elevated expression levels of PDGFreceptor [41,53]. Hence a study of PDGF receptorexpression in human arterial and venous SMC of bothT2DM and ND origin may be of value.

Persistent Vascular Cell Dysfunction – Evidenceof Metabolic Memory

Continued development of vascularcomplications as a result of prior exposure tohyperinsulinaemia and hyperglycaemia appears toconfer a persistent alteration of vascular gene expressionthat has been termed “metabolic memory” (reviewedin [10]). Follow-up studies of the DCCT trial revealedthat early, intensive glycaemic control in Type 1 diabeticpatients led to sustained benefits and bettermacrovascular outcomes [10]. Moreover it has recentlybeen proposed in T2DM, that minimising early exposureto hyperglycaemia is paramount [54], underpinning theidea that the change in cellular phenotype is not reversedby restoring glycaemic control at later time points.

Experimental studies have revealed that transienthigh glucose exposure can induce persistent phenotypicchanges and altered gene expression in the vasculature.For example, in diabetic mice progressiveatherosclerosis was noted after restoration ofnormoglycaemia following a period of hyperglycaemia[40]. Brief hyperglycaemia induced proinflammatorygene expression in aortic EC of non-diabetic mice invivo and in vitro, which was maintained even afterrestoration of normal glycaemia [55]. Furthermore,SMC cultured from diabetic db/db mouse aortaexhibited an increased inflammatory gene expressionprofile compared to non-diabetic db/+ SMC that wasretained throughout several passages [42,43]. Inaccordance, we have observed a distinct phenotype inhuman SV-SMC of T2DM origin (reduced proliferativecapacity, rhomboid morphology, f-actin fragmentation)that is retained throughout culture and passaging [37].Taken together, these studies lend support to the ideathat loss of SMC plasticity in T2DM may compromisevascular function through an inability to respond toenvironmental changes.

Thus, emerging perception is that prior metabolicdisturbance and hyperglycaemic exposure leaves anearly imprint on target cells of the vasculature. This ispotentially the origin of epigenetic changes, favouring

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vascular dysfunction that cannot simply be reversed byglucose normalisation. Whilst hyperglycaemia per seappears to be a key trigger, hyperinsulinaemia,advanced glycation end products (AGEs) and raisedlevels of proinflammatory cytokines, all of which areassociated with the diabetic phenotype [56], may alsobe important in this regard.

Clinical Perspectives

Epidemiological studies would predict thatmetabolic control should impact favourably oncardiovascular risk in diabetes (reviewed in [12]).However it is clear that this goal is not achieved usingcurrent therapeutics (reviewed in [3,9]). Despite theroutine use of drugs such as aspirin, statins, antiplateletdrugs, angiotensin receptor blockers, ACE inhibitorsand other antihypertensive agents, increasedcardiovascular disease in patients with T2DM remainsconsistently higher than that of individuals withoutdiabetes but receiving similar therapies.

Traditional markers for the development ofT2DM are obesity, lack of exercise, smoking andHbA1c above 6.0%. Although modulating these riskfactors can delay or prevent the development of T2DM[57], once established, reversing the detrimental effecton the vasculature appears more challenging. Asmentioned above, and in support of the reported“legacy” effect in the ACCORD, ADVANCE andVADT clinical trials [3,9], we have observed thatcultured SMC from T2DM individuals retain theirphenotypic profile in vitro and throughout several weeksto months of subculturing [37]. Such observationssuggest that SMC retain memory of previous metabolicdisturbance [58], whereby induced epigenetic changespersist even after the stimulus is removed, for examplewhen normal glucose levels are restored.

Current interests in molecular biomarkersencompass genomics, transcriptomics, proteomics andmetabolomics (reviewed in [59]). A variety of markershave been suggested that may precede the developmentof cardiovascular disease, for example plasminogen-activator-inhibtor-1 (PAI-1), interleukin-6 andphospholipase A2 [60] and are all implicated in T2DM[61-63]. However, these are likely to be effectors ofSMC dysfunction, rather than markers that originatefrom the SMC themselves and are indicative of theirphenotype.

MicroRNAs (miRs) are short non-coding RNAmolecules that can regulate gene expression bydegradation or translational repression of target mRNAs

[64]. Extensive research has shown that miRs areimportant in the regulation of diverse cellular functionsincluding those in the vasculature; hence aberrantexpression may lead to pathological states [65]. Recentstudies have demonstrated that miRs can modulateSMC phenotype (reviewed in [66]). Whilst miR-1, miR-10a and miR-145 are involved in directing thedifferentiation of stem cells into SMC [67-69], miR-21 promotes differentiation in response to TGFβ[70]and dedifferentiation via PDGF can be promoted bymiR-221 [71]. MiRs are also associated with multipleaspects of T2DM, with changes in expression beingreported in the liver, pancreatic beta cells, white adiposetissue and skeletal muscle [72]. The potential for miRsas biomarkers has been exemplified in studies wherebythe plasma miR profile of T2DM and ND patients wasexamined. One particular study reported reduced levelsof a number of miRs including miR-21 and endothelialmiR-126 and importantly, the reduction of miR-126 inthe plasma was observed prior to the development ofovert T2DM [73]. A different study focussed on 7miRs involved in the regulation of insulin geneexpression, all of which were found to be increased inthe plasma of T2DM subjects. However, thesedifferences were not apparent in the pre-diabetes period[74], hence restricting their use as early biomarkers.Identifying miRs that are directly linked to the T2DMSMC phenotype and subsequently investigating whetherthese can be reliably detected in plasma samples maytherefore be of greater value. The clinical potential ofmiR therapies is substantial, having already beenexplored in a variety of cancers. Indeed miRs lendthemselves to in vivo manipulation and are currently intranslational studies (reviewed recently in [75]).

Summary and Conclusions (see Figure 3)

In summary, there is emerging evidence of adistinct and persistent vascular SMC phenotype thatoccurs with T2DM. In vivo and in vitro studies indicatethat reinstating glucose control in itself is insufficient torestore vascular homeostasis and the scenario is clearlymore complex. Vascular complications of T2DM arelikely to be driven by cellular dysfunction/aberranciesinduced by metabolic memory.

Early detection of T2DM is critical for preventionof DM-related macrovascular disease, yet the naturalhistory of the condition makes this difficult.Cardiovascular disease is already evident in around halfof T2DM patients by the time of diagnosis. Recentstudies propose that plasma biomarkers hold potential

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for early detection of changes in SMC phenotype andfunction. A more complete understanding of theregulation of SMC dysfunction and identification ofspecific molecular markers would potentially revealnovel targets for therapy. Strategies to modulate cellphenotype and “correct” functional defects would beof considerable value, given the difficulties of earlydiagnosis of diabetes.

References

[1]Baker RG, Hayden MS, Ghosh S. NF-kB, inflammation, andmetabolic disease. Cell Metab 2011;13:11-22.

[2]Clinical Medicine. 7th ed. Edinburgh, New York: Elsevier/Saunders, 2009.

[3]Brown A, Reynolds LR, Bruemmer D. Intensive glycemiccontrol and cardiovascular disease: an update. Nat RevCardiol 2010;7:369-375.

[4]Flaherty JD, Davidson CJ. Diabetes and coronaryrevascularization. JAMA 2005;293:1501-1508.

[5]Beckman JA, Creager MA, Libby P. Diabetes andatherosclerosis: epidemiology, pathophysiology, andmanagement. JAMA 2002;287:2570-2581.

[6]Ruiter MS, van Golde JM, Schaper NC, Stehouwer CD,Huijberts MS. Diabetes impairs arteriogenesis in the peripheralcirculation: review of molecular mechanisms. Clin Sci (Lond)2010;119:225-238.

[7]Hakala T, Pitkanen O, Halonen P, Mustonen J, TurpeinenA, Hippelainen M. Early and late outcome after coronary arterybypass surgery in diabetic patients. Scand Cardiovasc J2005;39:177-181.

Inflammatory cytokines

AGEs

Aberrant

proliferation

and migration

Cytoskeletal

remodelling

e.g. F-actin

Morphological changes

e.g. Spread cell area

Signalling anomalies

e.g. PDGF receptor

Insulin receptor

Adhesion molecules

e.g. Vinculin, focal

adhesions

Extracellular matrix

composition

e.g. MMPs, collagen

‘Diabetes’ SMC

phenotype

‘Healthy’ SMC phenotype

Hyperglycaemia

Hyperlipidaemia

Hyperinsulinaemia

MicroRNA expression

e.g. miR-126

Figure 3: Characteristics of SMC from T2DM subjects. Metabolic and inflammatory conditions prevalent in type 2diabetes stimulate a change in smooth muscle cell phenotype leading to alterations in multiple aspects of cell biology andfunction.

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[8]Kubal C, Srinivasan AK, Grayson AD, Fabri BM, ChalmersJA. Effect of risk-adjusted diabetes on mortality and morbidityafter coronary artery bypass surgery. Ann Thorac Surg2005;79:1570-1576.

[9]Skyler JS, Bergenstal R, Bonow RO, Buse J, Deedwania P,Gale EA, Howard BV, Kirkman MS, Kosiborod M, Reaven P,Sherwin RS. Intensive glycemic control and the preventionof cardiovascular events: implications of the ACCORD,ADVANCE, and VA Diabetes Trials: a position statement ofthe American Diabetes Association and a Scientific Statementof the American College of Cardiology Foundation and theAmerican Heart Association. J Am Coll Cardiol 2009;53:298-304.

[10]Cooper ME. Metabolic memory: implications for diabeticvascular complications. Pediatr Diabetes 2009;10:343-346.

[11]Holman RR, Paul SK, Bethel MA, Matthews DR, Neil HA.10-year follow-up of intensive glucose control in type 2diabetes. N Engl J Med 2008;359:1577-1589.

[12]Reusch JE, Wang CC. Cardiovascular disease in diabetes:where does glucose fit in? J Clin Endocrinol Metab2011;96:2367-2376.

[13]Hermann C, Assmus B, Urbich C, Zeiher AM, Dimmeler S.Insulin-mediated stimulation of protein kinase Akt: A potentsurvival signaling cascade for endothelial cells. ArteriosclerThromb Vasc Biol 2000;20:402-409.

[14]Sydow K, Mondon CE, Cooke JP. Insulin resistance:potential role of the endogenous nitric oxide synthase inhibitorADMA. Vasc Med 2005;10 Suppl 1:S35-S43.

[15]Bugiardini R, Manfrini O, Pizzi C, Fontana F, Morgagni G.Endothelial function predicts future development of coronaryartery disease: a study of women with chest pain and normalcoronary angiograms. Circulation 2004;109:2518-2523.

[16]Schachinger V, Britten MB, Zeiher AM. Prognostic impactof coronary vasodilator dysfunction on adverse long-termoutcome of coronary heart disease. Circulation2000;101:1899-1906.

[17]Owens GK, Kumar MS, Wamhoff BR. Molecular regulationof vascular smooth muscle cell differentiation in developmentand disease. Physiol Rev 2004;84:767-801.

[18]Hao H, Gabbiani G, Bochaton-Piallat ML. Arterial smoothmuscle cell heterogeneity: implications for atherosclerosis andrestenosis development. Arterioscler Thromb Vasc Biol2003;23:1510-1520.

[19]Kawai-Kowase K, Owens GK. Multiple repressorpathways contribute to phenotypic switching of vascularsmooth muscle cells. Am J Physiol Cell Physiol 2007;292:C59-C69.

[20]Kawai-Kowase K, Ohshima T, Matsui H, Tanaka T,Shimizu T, Iso T, Arai M, Owens GK, Kurabayashi M. PIAS1mediates TGFbeta-induced SM alpha-actin gene expressionthrough inhibition of KLF4 function-expression by proteinsumoylation. Arterioscler Thromb Vasc Biol 2009;29:99-106.

[21]Han M, Dong LH, Zheng B, Shi JH, Wen JK, Cheng Y.Smooth muscle 22 alpha maintains the differentiated

phenotype of vascular smooth muscle cells by inducingfilamentous actin bundling. Life Sci 2009;84:394-401.

[22]Thyberg J, Nilsson J, Palmberg L, Sjolund M. Adult humanarterial smooth muscle cells in primary culture. Modulationfrom contractile to synthetic phenotype. Cell Tissue Res1985;239:69-74.

[23]Etienne P, Pares-Herbute N, Mani-Ponset L, Gabrion J,Rabesandratana H, Herbute S, Monnier L. Phenotypemodulation in primary cultures of aortic smooth muscle cellsfrom streptozotocin-diabetic rats. Differentiation 1998;63:225-236.

[24]Forst T, Hohberg C, Pfutzner A. Cardiovascular effects ofdisturbed insulin activity in metabolic syndrome and in type2 diabetic patients. Horm Metab Res 2009;41:123-131.

[25]Stout RW, Bierman EL, Ross R. Effect of insulin on theproliferation of cultured primate arterial smooth muscle cells.Circ Res 1975;36:319-327.

[26]Pfeifle B, Ditschuneit H. Effect of insulin on growth ofcultured human arterial smooth muscle cells. Diabetologia1981;20:155-158.

[27]Pfeifle B, Hamann H, Fussganger R, Ditschuneit H. Insulinas a growth regulator of arterial smooth muscle cells: effect ofinsulin of I.G.F.I. Diabete Metab 1987;13:326-330.

[28]Bornfeldt KE, Raines EW, Nakano T, Graves LM, KrebsEG, Ross R. Insulin-like growth factor-I and platelet-derivedgrowth factor-BB induce directed migration of human arterialsmooth muscle cells via signaling pathways that are distinctfrom those of proliferation. J Clin Invest 1994;93:1266-1274.

[29]Mughal RS, Scragg JL, Lister P, Warburton P, Riches K,O’Regan DJ, Ball SG, Turner NA, Porter KE. Cellularmechanisms by which proinsulin C-peptide prevents insulin-induced neointima formation in human saphenous vein.Diabetologia 2010;53:1761-1771.

[30]Kapur A, Hall RJ, Malik IS, Qureshi AC, Butts J, de BM,Baumbach A, Angelini G, de BA, Oldroyd KG, Flather M,Roughton M, Nihoyannopoulos P, Bagger JP, Morgan K, BeattKJ. Randomized comparison of percutaneous coronaryintervention with coronary artery bypass grafting in diabeticpatients. 1-year results of the CARDia (Coronary ArteryRevascularization in Diabetes) trial. J Am Coll Cardiol2010;55:432-440.

[31]Kornowski R, Mintz GS, Kent KM, Pichard AD, Satler LF,Bucher TA, Hong MK, Popma JJ, Leon MB. Increasedrestenosis in diabetes mellitus after coronary interventions isdue to exaggerated intimal hyperplasia. A serial intravascularultrasound study. Circulation 1997;95:1366-1369.

[32]Avena R, Mitchell ME, Neville RF, Sidawy AN. Theadditive effects of glucose and insulin on the proliferation ofinfragenicular vascular smooth muscle cells. J Vasc Surg1998;28:1033-1038.

[33]Cifarelli V, Luppi P, Tse HM, He J, Piganelli J, Trucco M.Human proinsulin C-peptide reduces high glucose-inducedproliferation and NF-kappaB activation in vascular smoothmuscle cells. Atherosclerosis 2008;201:248-257.

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[34]Kobayashi Y, Naruse K, Hamada Y, Nakashima E, Kato K,Akiyama N, Kamiya H, Watarai A, Nakae M, Oiso Y, NakamuraJ. Human proinsulin C-peptide prevents proliferation of rataortic smooth muscle cells cultured in high-glucoseconditions. Diabetologia 2005;48:2396-2401.

[35]Nakamura J, Kasuya Y, Hamada Y, Nakashima E, NaruseK, Yasuda Y, Kato K, Hotta N. Glucose-inducedhyperproliferation of cultured rat aortic smooth muscle cellsthrough polyol pathway hyperactivity. Diabetologia2001;44:480-487.

[36]Yamamoto M, Acevedo-Duncan M, Chalfant CE, Patel NA,Watson JE, Cooper DR. Acute glucose-induceddownregulation of PKC-betaII accelerates cultured VSMCproliferation. Am J Physiol Cell Physiol 2000;279:C587-C595.

[37]Madi HA, Riches K, Warburton P, O’Regan DJ, TurnerNA, Porter KE. Inherent differences in morphology,proliferation, and migration in saphenous vein smooth musclecells cultured from nondiabetic and Type 2 diabetic patients.Am J Physiol Cell Physiol 2009;297:C1307-C1317.

[38]Wang CC, Gurevich I, Draznin B. Insulin affects vascularsmooth muscle cell phenotype and migration via distinctsignaling pathways. Diabetes 2003;52:2562-2569.

[39]Kunjathoor VV, Wilson DL, LeBoeuf RC. Increasedatherosclerosis in streptozotocin-induced diabetic mice. J ClinInvest 1996;97:1767-1773.

[40]Brasacchio D, Okabe J, Tikellis C, Balcerczyk A, George P,Baker EK, Calkin AC, Brownlee M, Cooper ME, El-Osta A.Hyperglycemia induces a dynamic cooperativity of histonemethylase and demethylase enzymes associated with gene-activating epigenetic marks that coexist on the lysine tail.Diabetes 2009;58:1229-1236.

[41]Kawano M, Koshikawa T, Kanzaki T, Morisaki N, Saito Y,Yoshida S. Diabetes mellitus induces accelerated growth ofaortic smooth muscle cells: association with overexpressionof PDGF beta-receptors. Eur J Clin Invest 1993;23:84-90.

[42]Li SL, Reddy MA, Cai Q, Meng L, Yuan H, Lanting L,Natarajan R. Enhanced proatherogenic responses inmacrophages and vascular smooth muscle cells derived fromdiabetic db/db mice. Diabetes 2006;55:2611-2619.

[43]Villeneuve LM, Reddy MA, Lanting LL, Wang M, MengL, Natarajan R. Epigenetic histone H3 lysine 9 methylation inmetabolic memory and inflammatory phenotype of vascularsmooth muscle cells in diabetes. Proc Natl Acad Sci U S A2008;105:9047-9052.

[44]Faries PL, Rohan DI, Takahara H, Wyers MC, ContrerasMA, Quist WC, King GL, Logerfo FW. Human vascularsmooth muscle cells of diabetic origin exhibit increasedproliferation, adhesion, and migration. J Vasc Surg2001;33:601-607.

[45]Sawada N, Itoh H, Ueyama K, Yamashita J, Doi K, ChunTH, Inoue M, Masatsugu K, Saito T, Fukunaga Y, SakaguchiS, Arai H, Ohno N, Komeda M, Nakao K. Inhibition of rho-associated kinase results in suppression of neointimalformation of balloon-injured arteries. Circulation2000;101:2030-2033.

[46]Oikawa S, Hayasaka K, Hashizume E, Kotake H,Midorikawa H, Sekikawa A, Kikuchi A, Toyota T. Humanarterial smooth muscle cell proliferation in diabetes. Diabetes1996;45 Suppl 3:S114-S116.

[47]Chung AW, Luo H, Tejerina T, van BC, Okon EB. Enhancedcell cycle entry and mitogen-activated protein kinase-signalingand downregulation of matrix metalloproteinase-1 and -3 inhuman diabetic arterial vasculature. Atherosclerosis2007;195:e1-e8.

[48]Turner NA, Ho S, Warburton P, O’Regan DJ, Porter KE.Smooth muscle cells cultured from human saphenous veinexhibit increased proliferation, invasion, and mitogen-activated protein kinase activation in vitro compared withpaired internal mammary artery cells. J Vasc Surg 2007;45:1022-1028.

[49]van HL, Hamdani N, Handoko ML, Falcao-Pires I, MustersRJ, Kupreishvili K, Ijsselmuiden AJ, Schalkwijk CG, BronzwaerJG, Diamant M, Borbely A, van D, V, Stienen GJ, Laarman GJ,Niessen HW, Paulus WJ. Diastolic stiffness of the failingdiabetic heart: importance of fibrosis, advanced glycation endproducts, and myocyte resting tension. Circulation2008;117:43-51.

[50]Klemm AH, Diez G, Alonso JL, Goldmann WH. Comparingthe mechanical influence of vinculin, focal adhesion kinaseand p53 in mouse embryonic fibroblasts. Biochem BiophysRes Commun 2009;379:799-801.

[51]Liu AC, Gotlieb AI. Characterization of cell motility insingle heart valve interstitial cells in vitro. Histol Histopathol2007;22:873-882.

[52]Okon EB, Chung AW, Rauniyar P, Padilla E, Tejerina T,McManus BM, Luo H, van BC. Compromised arterial functionin human type 2 diabetic patients. Diabetes 2005;54:2415-2423.

[53]Yamaguchi H, Igarashi M, Hirata A, Sugae N, Tsuchiya H,Jimbu Y, Tominaga M, Kato T. Altered PDGF-BB-induced p38MAP kinase activation in diabetic vascular smooth musclecells: roles of protein kinase C-d. Arterioscler Thromb VascBiol 2004;24:2095-2101.

[54]Aizawa T, Funase Y. Intervention at the very early stageof type 2 diabetes. Diabetologia 2011;54:703-704.

[55]El-Osta A, Brasacchio D, Yao D, Pocai A, Jones PL, RoederRG, Cooper ME, Brownlee M. Transient high glucose causespersistent epigenetic changes and altered gene expressionduring subsequent normoglycemia. J Exp Med 2008;205:2409-2417.

[56]Yan SF, Ramasamy R, Schmidt AM. Mechanisms ofdisease: advanced glycation end-products and their receptorin inflammation and diabetes complications. Nat Clin PractEndocrinol Metab 2008;4:285-293.

[57]Gillies CL, Abrams KR, Lambert PC, Cooper NJ, SuttonAJ, Hsu RT, Khunti K. Pharmacological and lifestyleinterventions to prevent or delay type 2 diabetes in peoplewith impaired glucose tolerance: systematic review and meta-analysis. BMJ 2007;334:299.

[58]Ceriello A, Ihnat MA, Thorpe JE. The “metabolic memory”:is more than just tight glucose control necessary to prevent

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diabetic complications? J Clin Endocrinol Metab 2009;94:410-415.

[59]Herder C, Karakas M, Koenig W. Biomarkers for theprediction of type 2 diabetes and cardiovascular disease. ClinPharmacol Ther 2011;90:52-66.

[60]Koenig W, Khuseyinova N. Biomarkers of atheroscleroticplaque instability and rupture. Arterioscler Thromb Vasc Biol2007;27:15-26.

[61]Jankun J, Al-Senaidy A, Skrzypczak-Jankun E. Caninactivators of plasminogen activator inhibitor alleviate theburden of obesity and diabetes? (Review). Int J Mol Med2012;29:3-11.

[62]Kampoli AM, Tousoulis D, Briasoulis A, Latsios G,Papageorgiou N, Stefanadis C. Potential pathogenicinflammatory mechanisms of endothelial dysfunction inducedby type 2 diabetes mellitus. Curr Pharm Des 2011;17:4147-4158.

[63]Noto H, Chitkara P, Raskin P. The role of lipoprotein-associated phospholipase A(2) in the metabolic syndrome anddiabetes. J Diabetes Complications 2006;20:343-348.

[64]Bartel DP. MicroRNAs: target recognition and regulatoryfunctions. Cell 2009;136:215-233.

[65]Jamaluddin MS, Weakley SM, Zhang L, Kougias P, LinPH, Yao Q, Chen C. miRNAs: roles and clinical applications invascular disease. Expert Rev Mol Diagn 2011;11:79-89.

[66]Albinsson S, Sessa WC. Can microRNAs control vascularsmooth muscle phenotypic modulation and the response toinjury? Physiol Genomics 2011;43:529-533.

[67]Cordes KR, Sheehy NT, White MP, Berry EC, Morton SU,Muth AN, Lee TH, Miano JM, Ivey KN, Srivastava D. miR-145

and miR-143 regulate smooth muscle cell fate and plasticity.Nature 2009;460:705-710.

[68]Huang H, Xie C, Sun X, Ritchie RP, Zhang J, Chen YE.miR-10a contributes to retinoid acid-induced smooth musclecell differentiation. J Biol Chem 2010;285:9383-9389.

[69]Xie C, Huang H, Sun X, Guo Y, Hamblin M, Ritchie RP,Garcia-Barrio MT, Zhang J, Chen YE. MicroRNA-1 regulatessmooth muscle cell differentiation by repressing Kruppel-likefactor 4. Stem Cells Dev 2011;20:205-210.

[70]Davis BN, Hilyard AC, Lagna G, Hata A. SMAD proteinscontrol DROSHA-mediated microRNA maturation. Nature2008;454:56-61.

[71]Davis BN, Hilyard AC, Nguyen PH, Lagna G, Hata A.Induction of microRNA-221 by platelet-derived growth factorsignaling is critical for modulation of vascular smooth musclephenotype. J Biol Chem 2009;284:3728-3738.

[72]Ferland-McCollough D, Ozanne SE, Siddle K, Willis AE,Bushell M. The involvement of microRNAs in Type 2 diabetes.Biochem Soc Trans 2010;38:1565-1570.

[73]Zampetaki A, Kiechl S, Drozdov I, Willeit P, Mayr U,Prokopi M, Mayr A, Weger S, Oberhollenzer F, Bonora E,Shah A, Willeit J, Mayr M. Plasma microRNA profiling revealsloss of endothelial miR-126 and other microRNAs in type 2diabetes. Circ Res 2010;107:810-817.

[74]Kong L, Zhu J, Han W, Jiang X, Xu M, Zhao Y, Dong Q,Pang Z, Guan Q, Gao L, Zhao J, Zhao L. Significance of serummicroRNAs in pre-diabetes and newly diagnosed type 2diabetes: a clinical study. Acta Diabetol 2011;48:61-69.

[75]Nana-Sinkam SP, Croce CM. MicroRNAs as therapeutictargets in cancer. Transl Res 2011;157:216-225.

Secretary's Column

Chris Jackson

We welcome two new members onto the BSCR Committee, Dr Carolyn Carr, from the Department of

Physiology, Anatomy and Genetics at the University of Oxford and Professor Colin Berry from the Institute of

Cardiovascular and Medical Sciences at the University of Glasgow. Dr Chris Newman has finished his conspicuously

successful three year stint as Chair of the BSCR, and his successor is Dr Yvonne Alexander from Manchester. I

look forward to working with Yvonne until the end of my period as Secretary in 2013.

Our next Spring Meeting will once again be held jointly with the British Atherosclerosis Society and will

form part of the British Cardiovascular Society's annual conference: it is made possible by very generous sponsorship

from the British Heart Foundation. Organised by Colin Berry and Andrew Grace from the BSCR and Robin

Choudhury and James Rudd from the BAS, the topic is "New Frontiers in Cardiovascular Imaging: From Basic

Science to Clinical Application" and it will be held on May 28th and 29th in Manchester. I hope to see you there.

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I took over from Chris Newman as Chair of the BSCR on January 1st. I would like tothank Chris for his unstinting and devoted efforts in nurturing the BSCR over the past threeyears, which entailed a huge amount of hard work, often behind the scenes. It is an honourto chair a society where the research being directed and carried out by our members andyoung investigators is at the cutting edge of cardiovascular medicine, and we have a cultureof excellence and ambition which is evident through our high quality meetings held twiceyearly.

We have seen the introduction of some new ventures over recent years. First, thestrengthening of our relationship with like-minded societies, by combining our Spring meetingwith the British Cardiovascular Society Annual Scientific Conference and the BritishAtherosclerosis Society Spring meeting, securing a healthy future for our discipline andallowing our members the benefit of the extra events and input from both societies. TheBSCR is very pleased that the BCS and the British Heart Foundation have agreed to continueour participation in a joint meeting in the summer, and we find continued enthusiasm fromthe BAS to share the programme also.

Second, we have seen the introduction of the Marshall Prize Fund, a bequest from theestate of Bernard & Joan Marshall, which enables us to present three annual prizes: theMarshall Young Investigator Prize, the Marshall Research Excellence Prize, and the MarshallDistinguished Lectureship. Check our website for how to apply for these prestigious awards,or to make your suggestion for the lectureship.

Third, in support of the BHF’s “Mending Broken Hearts” appeal, the BSCR has launcheda new initiative, together with the BAS, to strengthen the public’s awareness of our societiesand the work we engage in, by organising a public event with a panel of speakers at the endof our Joint Spring meeting. This is designed for a wide audience of schools and health carepractitioners and members of the public.

I look forward to the challenge this new role brings and I will do my best to representthe interests of members of the BSCR over the next three years. I am keen to have yoursupport and suggestions on all matters of interest. In the meantime, although a little belated,I wish everyone a very Happy New Year and a productive and fruitful 2012. I look forwardto seeing you all at our future meetings and working with you in the interests of the BSCR.

Dr Yvonne Alexander

Chair, British Society for Cardiovascular Research

A Letter From Our New Chair

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The Bernard and Joan Marshall ResearchExcellence Prize Winner: Joseph Wu

Clinical Hurdles Facing Pluripotent Stem Cell Therapy

Eugene Gu1,2 and Joseph C. Wu1,2,3,4

1. Department of Medicine, Division of Cardiology; 2. Department of Radiology, Molecular ImagingProgram at Stanford (MIPS); 3. Institute for Stem Cell Biology and Regenerative Medicine; 4.Cardiovascular Institute, Stanford University School of Medicine, Stanford, California 94305, USA

Figure 1. Despite advances in the laboratory, there are

significant barriers preventing the transition from ani-

mal models to clinical trials. The three main issues con-

cern the limited cell survival, immunogenicity and tum-

origenicity.

AbstractWith their pluripotency and unlimited self-

renewal properties, both induced pluripotent andembryonic stem cells herald the exciting potential ofsomeday being able to treat a myriad of intractablediseases such as heart failure, spinal cord paralysis, anddiabetes. Despite the recent significant advances in ourunderstanding of stem cell biology, however, muchgreater progress is needed before therapeuticpossibilities can be realized in the future. Successfulclinical translation thus far has been hindered byproblems such as cell engraftment, immunogenicity, andtumorigenicity risk.

IntroductionIn 1998, James Thompson derived embryonic

stem cells (ESCs) from human blastocysts [1], and eightyears later, Shinya Yamanaka developed a method ofgenetically reprogramming fibroblasts into inducedpluripotent stem cells (iPSCs) [2]. Since these initialbreakthroughs, pluripotent stem cells have beenregarded as holding great promise for regenerativemedicine, in light of their capacity for self-renewal andpotential to transform into any cell type in the body.For instance, cardiomyocytes, chondrocytes, and evendopaminergic neurons derived from iPSCs and ESCshave been used to mitigate the symptoms of ischemicheart disease, osteoarthritis, and Parkinson’s diseasein animal models, respectively [3-8]. However, makingthe all-important leap from the bench to the clinic hasbeen hampered by persistent hurdles surrounding not

only limited stem cell engraftment, but also unansweredquestions regarding tumorigenicity and immunerejection (Figure 1). During the intervening years,significant efforts have focused on better understandingstem cell biology to realize the tantalizing dream of re-generative stem cell therapy. Traditionally, ex vivo his-topathological techniques have been used for post-mortem observations. However, these methods offer

16

Figure 2: Regardless of the transplanted cell type,very poor survival was observed in a small animalmodel of myocardial ischemia followingintramyocardial injection. MN, bone marrow mono-nuclear cells; SkMb, skeletal myoblasts; MSC,mesenchymal stem cells; Fibro, fibroblasts. Reprintedwith permission from [9].

only a very limited snapshot view into the criticallongitudinal process within the same living subject.Fortunately, the rapidly developing field of molecularimaging has now created the ability to observe intricatemechanisms in vivo, allowing researchers to betterunderstand and perhaps overcome the three mainhurdles to clinical therapy in the near future: limited stemcell survival, immunogenicity and tumorigenicity.

Limited Stem Cell SurvivalBefore pluripotent stem cell therapy can become

the standard of care for a variety of chronic anddegenerative diseases, long-term survival of these cellsin animal models must first be achieved. To this end,molecular imaging using reporter gene techniques offerhighly effective modalities for studying pluripotent stemcell survival, given their high sensitivity, exclusiveexpression in living cells and signal propagation bydaughter cells [9]. One of the first studies to investigate

transplanted cell survival in the myocardium used bothfirefly luciferase (Fluc) and herpes simplex type 1 thy-midine kinase (HSV1tk) reporter genes to show thatmolecular imaging correlated with ex vivo histopatho-logical examination [10]. Subsequent studies soon madeit clear that very few stem cells could effectively survivein the targeted tissues of interest over the long term.For instance, one study found that bone marrowmononuclear cells (MN), skeletal myoblasts (SkMb),and mesenchymal stem cells (MSC) all displayed asurvival rate of less than 0.5% after six weeks (Figure2) [11]. Similarly, transplantation of Sca-1 positivecardiac stem cells (CSC) in a mouse model ofmyocardial infarction showed ∼ 0.5% of the cellssurvived after eight weeks [12]. Given such dismalsurvival rates of various stem cells in the myocardium,many groups have searched for various solutions, in-cluding the overexpression of certain pro-survival genessuch as BCL2. Encoding a protein with four homologydomains located on the outer mitochrondrial membrane(OMM), BCL2 is known to regulate apoptosis bycontrolling the permeability of the OMM to cytochromec [13]. One group has shown that BCL2overexpression enhances ESC survival during stressfrom single cell sorting and dissociation, whereas anothergroup demonstrated that overexpression of this genepromotes the survival of cardiomyoblasts in infarctedrat hearts [14, 15]. Other researchers have turned tomicroRNAs as a means to suppress downstream pro-apoptotic genes. For example, one study used acombination of three miRNAs (miR-21, miR-24 andmiR-221) to increase the survival of CSCs in a mousemyocardial infarction model. In this case, the CSCswere still detected four weeks after transplantation [16].

One obvious disadvantage to genetic manipu-lation lies in the potential for insertional mutagenesis, anunacceptable risk for therapeutic applications inhumans. To tackle this problem, it may be more fruitfulto examine the underlying biological mechanismsinvolved in stem cell survival and to tailor specificstrategies in response. For example, one reason thatstem cells have difficulty surviving in the targeted tissuesmay be that cells which are mobilized into infarctedtissue experience hypoxic stress and diminished blood

17

flow and nutrients [17]. One group noted that stromalcell-derived factor 1 alpha (SDF-1α) is a potentchemoattractant secreted by cells in the ischemicmyocardium that interacts with the C-X-C chemokinereceptor type 4 (CXCR-4). By overexpressing CXCR-4, MSCs were shown to have significantly higherengraftment and survival in ischemic tissue [18].However, modification of CXCR-4 expression stillrequired the use of genetic manipulation, which isdifficult to apply to clinical use. Other promising methodsinclude hypoxic preconditioning (HP) and the use ofscaffolding biomaterials, which may improve stem cellsurvival in ischemic zones without increasing the risk ofinsertional mutagenesis. One group showed that HP-treated human adipose derived stem cells had increasedlevels of hypoxia inducible factor-1 alpha (HIF-1α) andexhibited significantly higher survival than controls [19].Another group showed that injection of self-assemblingpeptide nanofibers could thicken the infarctedmyocardium within pigs and increase both theengraftment and survival of bone marrow mononuclearcells [20].

Facing the Immune BarrierOver the years, the immunogenicity of pluripo-

tent stem cells have gone through many disprovedhypotheses and false starts until more thoroughinvestigations revealed that the complexities of theimmune barrier precluded any simple, readily availablefix. For instance, initially it was widely believed thatESCs were immune privileged due to their limited majorhistocompatibility complex (MHC) class I expressionand low expression of costimulatory molecules [21].This misconception was disproven when several groupsshowed that ESCs could elicit an immune response invivo within mice due to their low but still present ex-pression of foreign MHC class I expression [22, 23].Likewise, the notion that iPSCs were immune privilegedwas challenged recently by another group that foundthe process of reprogramming somatic cells into iPSCsinduced abnormal gene expression, leading to T-cellmediated responses [24]. Hence the immunogenicityof pluripotent stem cells and their derivatives maypresent a formidable barrier to clinical translation and

must be thoroughly investigated and understood beforeclinical work could safely commence.

While MHC antigens are well-known mediatorsof immune rejection, other immunogenic molecules alsoplay significant roles in the rejection of therapeutic stemcells within the host. Minor histocompatibility antigens,which are normal cell surface proteins naturallypolymorphic in a given population, have been shownto elicit an immune response sufficient to cause rejection[25]. Even if all the MHC antigens between donor andhost were concordant, expression of aberrant genessuch as Hormad1 and Zg16 in undifferentiated mouseiPSCs have been shown to activate both helper andcytotoxic T-lymphocytes [24]. Another consideration,especially when hematopoietic stem cells are involved,is ABO incompatibility. One group has shown that ESCscan express low levels of A and B blood type antigensaccording to ABO genotype [26]. Althoughcomplement-mediated hyperacute rejection, as seenwith vascularized organ transplants, may not occur instem cells with discordant ABO expression, it remainsto be seen whether antibody binding can promoteantibody-dependent cell mediated cytotoxicity orphagocytosis by natural killer cells and macrophages,respectively.

Similar to some of the methods used to improvestem cell survival, two genetic overexpressiontechniques have been employed to evade the hostimmune system. One is the overexpression of Fas ligand(FasL), a transmembrane protein that induces apoptosisof cytotoxic T-cells and which is responsible formaintaining the immune privileged status of the placenta,testes, brain, and cornea. In fact, one study has shownthat the expression of FasL by bone marrow stem cellsinduced the apoptosis of activated lymphocytes [27].The other technique is the overexpression of Serineprotease inhibitor 6 (Serpin 6), an inhibitor of granzymeB found with natural killer cells and cytotoxic T-cells.One group showed that ESCs induced to overexpressSerpin 6 were more resistant to lysis by antigen-specificcytotoxic T-cells [28]. However, as with all geneticmanipulation techniques, the risk of insertionalmutagenesis makes them unpalatable for use in theclinic. Although long-term immunosuppression through

18

the use of pharmacological drugs can present the riskof opportunistic infections, it is nevertheless the moststraightforward way to deal with the immunogenicitybarrier. Indeed, it is the standard of care for solid organtransplant recipients and has been investigated for stemcell therapies in animal models as well. One studyshowed that immunocompetent mice reject humanESCs within 7 to 10 days, but the rejection processcan be delayed up to 28 days upon administration ofT-cell inhibitors such as sirolimus and tacrolimus [29].Even more promising is another study showing thathuman ESCs and iPSCs transplanted intoimmunocompetent mice can survive long-term with theshort-term use of leukocyte costimulatory blockademolecules [30]. A short-course blockade of CD28,CD40 ligand, and lymphocyte-associated antigen-1 wasfound to be more effective than conventionalimmunosuppressants in preventing the rejection ofpluripotent stem cell grafts [30]. Moreover, since long-term immunosuppression was not required in this case,the risks of opportunistic infections and malignancy canbe reduced.

The Risks of TumorigenicityThe potential risk of malignant cancer resulting

from stem cell therapy is probably the most fearsomebarrier to clinical application. Inherently, the sameproperties of self-renewal and rapid proliferation thatmake pluripotent stem cells good candidates forregenerative medicine also make them prone tomalignant transformation [31, 32]. To exacerbate theproblem even further, the reprogramming process usedto create iPSCs and the genetic manipulations used toimprove survival, evade host immune defenses, ormonitor cells in vivo can create more opportunities forgenetic mutations leading to cancer. Even secondaryconsiderations must be taken into account as well. Forinstance, although not directly caused by stem cells ortheir derivatives, malignancies may arise from thepharmacological immunosuppression necessary forgrafts to survive. Indeed, the risks of post-transplantlymphoproliferative disorder (PTLD) is 20-fold greaterin transplant recipients than in the general population,and is largely attributed to the chronicallyimmunosuppressed state [33].

The formation of teratomas is the gold stan-dard for assessing the pluripotency of ESC and iPSClines in vivo. Although teratomas are considered benigntumors, they still possess the potential to transform intomalignant teratocarcinomas [32]. Moreover, when fullydifferentiated cells such as cardiomyocytes arecontaminated with sufficient numbers of undifferentiatedESCs during cell transplantation procedures, teratomaformation within the organs may result in adverseconsequences [32]. One study showed that teratomaformation is dependent upon the number of transplantedESCs, with a minimum of ∼ 1x105 cells required to formteratomas in murine hearts [34]. Another study showedthat the heart is not conducive to guiding undifferentiatedESCs into cardiomyocytes and that teratomas form atthe same rate in the myocardium as they do in the hindlimb [35].

Molecular imaging has also played a crucial rolein elucidating the underlying mechanisms of stem celltumorigenicity. One group has shown that upregulationof á

vâ

3 integrin plays a predominant role in tumor

angiogenesis and can be tracked using direct PETimaging with Copper-14 bound to an arginine-glycine-aspartic (RGD) tetramer. [36]. Another study usingsodium iodide symporter (NIS) reporter genetechnology showed that mesenchymal stem cells migrateto growing tumors and differentiate into vasculaturestructures to support the process of angiogenesis [37].Although reporter gene technology presents a risk forinsertional mutagenesis, this risk can be mitigatedbecause it can also be used as a fail-safe “suicideswitch” to stop malignant transformation. For example,one group showed that administering ganciclovir to cellsexpressing the HSV1tk reporter gene could selectivelykill them, providing a convenient safety option to dealwith unexpected malignancies [38]. Another groupshowed that a NIS reporter gene could act as a fail-safe mechanism when administering radioactive iodine-131 [39].

Future DirectionsIt is clear that several important hurdles must be

overcome before pluripotent stem cells can be used inthe clinic. Molecular imaging has played a pivotal role

19

not only in elucidating the problems of limited cellsurvival, potential immunogenicity, and risks oftumorigenicity, but has also offered possible solutionssuch as by providing a fail-safe suicide switch to guardagainst malignancy. As the advent of molecular imaginghas displaced the prior gold standard of post-mortemhistopathological analysis, researchers are nowemploying emerging technologies to gain profound newinsights in stem cell biology. One such possibledevelopment is the creation of human-to-rat or human-to-mouse xenotransplantation models that might allowtesting of human stem cells in human organs withoutincurring the same cost and difficulties of clinical trials.Another exciting development that may shorten the pathto clinical trials is the use of disease-specific iPSCs indrug discovery efforts. Whatever the future holds, it isclear that pluripotent stem cells will continue to play aprominent role in both regenerative medicine andbiomedical science as a whole.

References1. Thomson JA, Itskovitz-Eldor J, Shapiro SS, Waknitz MA,Swiergiel JJ, Marshall VS. et al. Embryonic stem cell linesderived from human blastocysts. Science. 1998;282:1145-7.

2. Takahashi K, Yamanaka S. Induction of pluripotent stemcells from mouse embryonic and adult fibroblast cultures bydefined factors. Cell. 2006;126:663-76.

3. Wernig M, Zhao JP, Pruszak J, Hedlund E, Fu D, Soldner F.et al. Neurons derived from reprogrammed fibroblasts func-tionally integrate into the fetal brain and improve symptomsof rats with Parkinson’s disease. Proc Natl Acad Sci U S A.2008; 105: 5856-61.

4. Yang D, Zhang ZJ, Oldenburg M, Ayala M, Zhang SC.Human embryonic stem cell-derived dopaminergic neuronsreverse functional deficit in parkinsonian rats. Stem Cells.2008; 26:55-63.

5. Djouad F, Bouffi C, Ghannam S, Noel D, Jorgensen C.Mesenchymal stem cells: innovative therapeutic tools forrheumatic diseases. Nat Rev Rheumatol. 2009; 5: 392-9.

6. Zhang J, Wilson GF, Soerens AG, Koonce CH, Yu J, PalecekSP. et al. Functional cardiomyocytes derived from humaninduced pluripotent stem cells. Circ Res. 2009;104: e30-41.

7. Cao F, Wagner RA, Wilson KD, Xie X, Fu JD, Drukker M. etal. Transcriptional and functional profiling of humanembryonic stem cell-derived cardiomyocytes. PLoS One. 2008;3: e3474.

8. Nelson TJ, Martinez-Fernandez A, Yamada S, Perez-TerzicC, Ikeda Y, Terzic A. Repair of acute myocardial infarction by

human stemness factors induced pluripotent stem cells.Circulation. 2009; 120: 408-16.

9. Li Z, Suzuki Y, Huang M, Cao F, Xie X, Connolly AJ. et al.Comparison of reporter gene and iron particle labeling fortracking fate of human embryonic stem cells and differentiatedendothelial cells in living subjects. Stem Cells. 2008; 26: 864-73.

10. Wu JC, Chen IY, Sundaresan G, Min JJ, De A, Qiao JH. etal. Molecular imaging of cardiac cell transplantation in livinganimals using optical bioluminescence and positron emissiontomography. Circulation. 2003; 108: 1302-5.

11. van der Bogt KE, Sheikh AY, Schrepfer S, Hoyt G, Cao F,Ransohoff KJ. et al. Comparison of different adult stem celltypes for treatment of myocardial ischemia. Circulation. 2008;118: S121-9.

12. Li Z, Lee A, Huang M, Chun H, Chung J, Chu P. et al.Imaging survival and function of transplanted cardiac residentstem cells. J Am Coll Cardiol. 2009; 53: 1229-40.

13. Chipuk JE, Moldoveanu T, Llambi F, Parsons MJ, GreenDR. The BCL-2 family reunion. Mol Cell. 2010;37:299-310.

14. Ardehali R, Inlay MA, Ali SR, Tang C, Drukker M,Weissman IL. Overexpression of BCL2 enhances survival ofhuman embryonic stem cells during stress and obviates therequirement for serum factors. Proc Natl Acad Sci U S A.2011; 108: 3282-7.

15. Kutschka I, Kofidis T, Chen IY, von Degenfeld G,Zwierzchoniewska M, Hoyt G. et al. Adenoviral human BCL-2 transgene expression attenuates early donor cell death aftercardiomyoblast transplantation into ischemic rat hearts.Circulation. 2006; 114: I174-80.

16. Hu S HM, Nguyen PK, Gong Y, Li Z, Jia F. et al. NovelmicroRNA prosurvival cocktail for improving engraftment andfunction of cardiac progenitor cell transplantation.Circulation. 2011;13:124(11 Suppl): S27-34.

17. Mangi AA, Noiseux N, Kong D, He H, Rezvani M, IngwallJS, et al. Mesenchymal stem cells modified with Akt preventremodeling and restore performance of infarcted hearts. NatMed. 2003;9:1195–201

18. Zhang D, Fan GC, Zhou X, Zhao T, Pasha Z, Xu M. et al.Over-expression of CXCR4 on mesenchymal stem cellsaugments myoangiogenesis in the infarcted myocardium. JMol Cell Cardiol. 2008; 44: 281-92.

19. Stubbs SL, Hsiao ST, Peshavariya H, Lim SY, Dusting GJ,Dilley RJ. Hypoxic preconditioning enhances survival ofhuman adipose-derived stem cells and conditions endothelialcells in vitro. Stem Cells Dev. 2011 Dec 14. [Epub ahead ofprint]

20. Lin YD, Yeh ML, Yang YJ, Tsai DC, Chu TY, Shih YY. et al.Intramyocardial peptide nanofiber injection improvespostinfarction ventricular remodeling and efficacy of bonemarrow cell therapy in pigs. Circulation. 2010;122(11

Suppl):S132-41.

21. Magliocca JF, Held IK, Odorico JS. Undifferentiated murineembryonic stem cells cannot induce portal tolerance but maypossess immune privilege secondary to reduced major histo-

20

Correspondence to:

Dr Joseph C. Wu, MD, PhD.

265 Campus Drive, Rm G1120B,

Stanford CA 94305

Email: [email protected]

compatibility complex antigen expression. Stem Cells Dev.2006;15:707-717.

22. Swijnenburg RJ, Schrepfer S, Cao F, Pearl JI, Xie X,Connolly AJ. et al. In vivo imaging of embryonic stem cellsreveals patterns of survival and immune rejection followingtransplantation. Stem Cells Dev. 2008; 17: 1023-9.

23. Robertson NJ, Brook FA, Gardner RL, Cobbold SP,Waldmann H, Fairchild PJ. Embryonic stem cell-derived tissuesare immunogenic but their inherent immune privilege promotesthe induction of tolerance. Proc Natl Acad Sci U S A. 2007;104: 20920-5.

24. Zhao T, Zhang ZN, Rong Z, Xu Y. Immunogenicity ofinduced pluripotent stem cells. Nature. 2011; 474: 212-5.

25. Wallny HJ, Rammensee HG. Identification of classical minorhistocompatibility antigen as cell-derived peptide. Nature.1990;343:275-278.

26. Molne J, Bjorquist P, Andersson K, Diswall M, JeppssonA, Strokan V, Rydberg L, Breimer ME. Blood group ABOantigen expression in human embryonic stem cells and indifferentiated hepatocyte- and cardiomyocyte-like cells.Transplantation. 2008;86:1407-1413.

27. Mazar J, Thomas M, Bezrukov L, Chanturia A, PekkurnazG, Yin S. et al. Cytotoxicity mediated by the Fas ligand (FasL)-activated apoptotic pathway in stem cells. J Biol Chem. 2009;284:22022-8.

28. Abdullah Z, Saric T, Kashkar H, Baschuk N, YazdanpanahB, Fleischmann BK. et al. Serpin-6 expression protectsembryonic stem cells from lysis by antigen-specific CTL. JImmunol. 2007;178:3390-9.

29. Swijnenburg RJ, Schrepfer S, Govaert JA, Cao F, RansohoffK, Sheikh AY . et al. Immunosuppressive therapy mitigatesimmunological rejection of human embryonic stem cell xe-nografts. Proc Natl Acad Sci U S A. 2008; 105: 12991-6.

30. Pearl JI, Lee AS, Leveson-Gower DB, Sun N, Ghosh Z, LanF. et al. Short-term immunosuppression promotes engraftmentof embryonic and induced pluripotent stem cells. Cell StemCell. 2011; 8: 309-17.

31. Ben-David U, Benvenisty N. The tumorigenicity of humanembryonic and induced pluripotent stem cells. Nat RevCancer. 2011; 11: 268-77.

32. Kooreman NG, Wu JC. Tumorigenicity of pluripotent stemcells: biological insights from molecular imaging. J R SocInterface. 2010; 7 Suppl 6: S753-63.

33. Kew CE 2nd, Lopez-Ben R, Smith JK et al. Posttransplantlymphoproliferative disorder localized near the allograft inrenal transplantation. Transplantation 2000; 69: 809-814.

34. Lee AS, Tang C, Cao F, Xie X, van der Bogt K, Hwang A.et al. Effects of cell number on teratoma formation by humanembryonic stem cells. Cell Cycle. 2009; 8: 2608-12.

35. Nussbaum J, Minami E, Laflamme MA, Virag JA, Ware CB,Masino A. et al. Transplantation of undifferentiated murineembryonic stem cells in the heart: teratoma formation andimmune response. FASEB J. 2007;21:1345-57.

36. Cao F, Li Z, Lee A, Liu Z, Chen K, Wang H. et al.Noninvasive de novo imaging of human embryonic stem cell-derived teratoma formation. Cancer Res. 2009; 69: 2709-13.

37. Dwyer RM, Ryan J, Havelin RJ, Morris JC, Miller BW, LiuZ. et al. Mesenchymal Stem Cell-mediated delivery of thesodium iodide symporter supports radionuclide imaging andtreatment of breast cancer. Stem Cells. 2011; 29: 1149-57.

38. Cao F, Drukker M, Lin S, Sheikh AY, Xie X, Li Z. et al.Molecular imaging of embryonic stem cell misbehavior andsuicide gene ablation. Cloning Stem Cells. 2007; 9:107-17.

39. Dwyer RM, Ryan J, Havelin RJ, Morris JC, Miller BW, LiuZ. et al. Mesenchymal Stem Cell-mediated delivery of thesodium iodide symporter supports radionuclide imaging andtreatment of breast cancer. Stem Cells. 2011; 29: 1149-57.

Volume Date Deadline

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25 (3) July 2012 1st June

25 (4) October 2012 1st September

26 (1) January 2013 1st December

Submission Deadlines

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The Bulletin:

21

The Bernard and Joan Marshall YoungInvestigator Prize Winner: Joseph R. Burgoyne

Sir Henry Wellcome Postdoctoral Fellow, King’s College London

A role for protein palmitoylation in vascularendothelial dysfunction of obese animals

The obesity epidemicThe steady rise in the prevalence of obesity since theturn of century has put an overwhelming burden on theNational Health Service due to the complications arisingfrom this epidemic, which includes cardiovasculardisease, type II diabetes, liver disease and several formsof cancer. This is an escalating problem as predictionsfor the future forecast that, by 2050, 60% of men and50% of woman will be classified as obese1. It istherefore imperative that, not only the underlying causeof this epidemic is addressed, by direct changes in thepopulation’s diet and exercise through improvededucation and restrictions on food content, but also byimprovements in medical and pharmacologicaltreatment for those already obese2. The importance ofthese strategies are clearly essential in limiting the preva-lence of cardiovascular disease with the risk of coronaryartery disease increasing 3.6 times per additional unitof BMI and 85% of people with hypertension beingassociated with a BMI of over 253. We can increasethe likelihood of developing rational interventions andnovel pharmacological treatments to combat cardio-vascular disease in obese patients by better understand-ing the biochemical processes integral to thepathogenesis.

Protein post translational modifications modulatediseaseDefining differences in signalling in healthy and diseasecells and tissues may provide clues about pathogenicmechanisms and thereafter novel drug targets.However, this can be very challenging due to thecomplexity of the processes that regulate cell function

which include an exhaustive array of diverse posttranslational modifications that alter the activity ofproteins. The best understood regulatory modificationis phosphorylation, but there is increasing evidence thatproteins are also modified and regulated by oxidativemodification4, including by a variety of lipids5. Thesemodifications can play a fundamental role in cellularsignalling by altering protein function by changing itsstructure; for example the addition of a hydrophobicalkyl lipid chain can enhance association with membranecompartments. To identify changes in the posttranslational modifications of a protein within a diseasescenario, techniques must be utilised that reliably andselectively detect the specific type of post translationalmodification. The ease and routine analysis of posttranslational modifications is dependent on the specifictype of modification. For example, proteinphosphorylation is readily detectable using phospho-specific antibodies, radioactive isotope labelledphosphate in ATP or mass spectrometry. However suchmethods cannot be generically applied to the diverserange of oxidation or lipidation states that can occur inprotein. Whilst phosphospecific antibodies are com-mon, generic investigative tools, this strategy hasn’t beenso widely effective for lipid and oxidative modification.This is perhaps attributable to limited antigenicity andstability of some of the oxidation and lipidation modifi-cations of interest. Therefore alternative methods, oftenmore complex, have been developed that allow detectionof such modifications. One such technique, termed the‘biotin-switch assay’, allows a specific proteinmodification to be identified. This is achieved byselective chemical reduction of the modified cysteines

22

Figure 1. A) Diagram showing each stage of the biotin-switch assay, which essentially comprises of three steps. The first

step is alkylation of free cysteines thiols followed by selective reduction of modified cysteines and then thirdly labelling of

newly available thiols with a biotin-tagged alkylating agent. Proteins carrying the biotin-tag can be detected on Western

blots using streptavidin-HRP or they can be purified using streptavidin-sepharose. B) The different modifications that can

be selectively detected using the biotin-switch assay following their specific chemical or enzymatic reduction, giving rise to

free cysteine thiols that can then be labelled with a biotin-tagged akylating agent.

followed by labelling of these newly available free thiols(SH) with a biotinylated alkylating agent (see Figure1)6, 7. This approach has been utilised in the investiga-tion of reversible lipidation of proteins by palmitate(palmitoylation) and the oxidative modification S-nitrosylation, and to a lesser extent protein glutathiolationand sulfenation.

Thiol oxidation regulates protein functionAlterations in the oxidation status of proteins were onceconsidered as markers, potentially causative, of disease.However, this view has changed, and oxidativemodification of proteins is now accepted as being animportant mediator of physiological signalling8. Thedifference being that under physiological conditionsregulated reversible oxidation of proteins act as subtlemodulators of function analogous to phosphorylation,whereas pathological increases in oxidant formation leadto aberrant or irreversible modifications that promote

aberrant signalling and disease progression. Oxidantsare generated under physiological conditions by anumber of different sources including leak from themitochondrial electron transport chain, as by-productsof a number of cellular oxidases and as the primaryoutput of the NADPH oxidases. These oxidants cangenerate reversible oxidative modifications onsusceptible cysteine thiols which generally exist in thereactive thiolate anion (S-) state. Oxidants modifythiolates to yield a diverse array of modifications,including the relatively unstable sulfenic (SOH) and S-nitrosothiol (SNO) species, and the more stabledisulphide (S-S) and glutathione adducts (S-SG)4. Therelatively unstable modifications, protein sulfenates ornitrosothiols, generally transition to a more stablereversible modification through reaction with a secondproximal cysteine thiol on the same protein, anotherprotein or glutathione, forming a disulphide. Oxidativemodifications of proteins can be reversed back to the

23

Figure 2. Under normal physiological conditions farnesylated HRas is palmitoylated at the Golgi by the protein

acyltransferase (PAT) at two C-terminal cysteine residues. Palmitoylation at both sites induces exocytic transport of HRas

from the Golgi to the plasma membrane. Once at the plasma membrane HRas is able to mediate growth factor signalling

required for cell growth and survival. Plasma membrane bound HRas can also return to the Golgi following depalmitoylation

by acyl protein thioesterase (APT), where it can begin the lipidation cycle again. In vascular endothelial cells treated with

HFHS there is increased oxidant formation from the mitochondria that increases the glutathiolation of H-Ras, preventing

palmitoylation at either of the modifiable cysteines residues. This attenuates the exocytic transport of HRas trapping it at

the Golgi, which prevents growth factor signalling required for cell survival.

basal reduced state by enzymes such as thioredoxin orglutaredoxin9. This reversibility gives protein thioloxidation the dynamic and regulatory propertiesrequired to mediate subtle changes in cellular signalling.However this process can be disrupted duringpathology due to excessive increases in oxidantformation that can drive cysteines to higher irreversibleoxidation states that include sulfinic (SO

2H) and sulfonic

acid (SO3H), which are termed hyperoxidation.

Protein palmitoylationIn addition to the modification of cysteines by oxidants,some thiols in a particular, correct environment canundergo the addition of a lipid moiety, a process termedlipidation10. This is an enzymatic process wherebydifferent types of lipid, including palmitate (C-16),farnesyl (C-15) or geranylgeranyl (C-20), can beattached to a cysteine thiol. The addition of a farnesyl(farnesylation) or geranylgeranyl (geranylgeranylation)moiety to a cysteine is irreversible due to the formationof a stable thioether bond. However the coupling ofpalmitate (palmitoylation) is reversible as the thioester

linkage formed between the lipid and the thiol can bereadily hydrolysed. The hydrolysis of the thioester bondis mediated by the enzyme acyl protein thioesterase.The enzymatic reversibility of palmitoylation hasgenerated widespread interest in the potential role ofthis modification as a dynamic regulator of proteinfunction by controlling membrane interactions,intracellular localisation and potential protein stability11.

Dysfunctional HRas palmitoylation during obesityAn early mediator in growth factor-mediated signallingis the small GTPase HRas. For HRas to mediate thissignalling it must first be palmitoylated at two C-terminalcysteine residues12, which induces exocytic transportof this GTPase from the Golgi to the plasma membrane.Once stimulated, the plasma membrane bound HRasactivates the Raf/MEK/ERK pathway, which ultimatelyleads to improved endothelial cell survival and prolif-eration by enhancing DNA transcription13, 14. In mystudy I found that, in cardiac tissue from mice fed with,or cultured aortic endothelial cells treated with, high fatand high sugar (HFHS), there was a loss in the

24

palmitoylation of HRas, detected using the hydroxy-lamine dependent biotin-switch assay15. This effect isaccompanied by a loss in the interaction of HRas withRaf in aortic endothelial cells and also a decrease inbasal ERK phosphorylation in both aortic endothelialcells and in heart tissue. This apparent loss in HRasactivity was due to accumulation of HRas at the Golgi,which was observed using confocal microscopy. Theloss in HRas plasma membrane localisation and signal-ling through decreased palmitoylation was due toincreased oxidation of the C-terminal cysteines byglutathione, which prevented their palmitoylation whichwould normally occur in the absence of oxidant stress.This was demonstrated using tandem massspectrometry, which showed a large increase in HRasthat was only palmitoylated at a single site andglutathiolated at the other in aortic endothelial cellstreated with HFHS compared to control media. Thefunctional impact of decreased HRas plasma membranesignalling was clearly evident from an increase inendothelial cell apoptosis that could be attenuated byoverexpressing wild-type HRas but not a non-palmitoylatable mutant (C181/184S). In addition,inhibiting HRas activity at the membrane byoverexpressing a dominant negative inactive form(N17HRas), mimicked the effects of HFHS treatmentby also increasing aortic endothelial cell apoptosis. Arole for oxidants in mediating endothelial dysfunction inHFHS treated aortic endothelial cells was demonstratedby overexpressing manganese superoxide dismutase(MnSOD), which protected cells from apoptosis,improved HRas palmitoylation and increased ERKphosphorylation. Furthermore, the effect ofoverexpressing MnSOD suggests that mitochondria arethe likely source of oxidants in HFHS treated aorticendothelial cells. These findings together highlight apathophysiological mechanism of cellular dysfunction,caused by metabolic stress, whereby increases inoxidant formation disrupt normal HRas palmitoylationand plasma membrane signalling. These findings alsoprovide a potential molecular mechanism to explainimpaired angiogenesis and growth factor resistance inpatients with vascular disease associated with themetabolic syndrome as reported in the VIVA, FIRST

and AGENT clinical trials16-18. In addition, thispathological mechanism of endothelial dysfunction mayplay an important role in the development of athero-sclerosis, which is prevalent in obese patients19.

AcknowledgementsI would like to thank Professor Richard Cohen and DrMarkus Bachschmid from Boston University for theirsupport and access to facilities. In addition, I wouldalso like to thank my mentor Professor Philip Eaton forhis support and guidance during the duration of myscientific career.

References1. Kopelman, P., Jebb, S.A., & Butland, B. ‘Tackling obesities:Future choices’ project. Obesity Reviews 8, Vi-Ix (2007).

2. Health, D.o., Healthy Weight, Healthy Lives: A CrossGovernment Strategy for England, 2008.

3. Kopelman, P. Health risks associated with overweight andobesity. Obesity Reviews 8 Suppl 1, 13-7 (2007).

4. Wouters, M.A., Iismaa, S., Fan, S.W., & Haworth, N.L. Thiol-based redox signalling: rust never sleeps. Int J Biochem CellBiol 43(8), 1079-85 (2011).

5. Levental, I., Grzybek, M., & Simons, K. Greasing their way:lipid modifications determine protein association withmembrane rafts. Biochemistry 49(30), 6305-16 (2010).

6. Burgoyne, J.R.& Eaton, P. A rapid approach for thedetection, quantification, and discovery of novel sulfenic acidor S-nitrosothiol modified proteins using a biotin-switchmethod. Methods Enzymol 473, 281-303 (2010).

7. Burgoyne, J.R.& Eaton, P. Contemporary techniques fordetecting and identifying proteins susceptible to reversiblethiol oxidation. Biochem Soc Trans 39(5), 1260-7 (2011).

8. Finkel, T. Signal transduction by reactive oxygen species. JCell Biol 194(1), 7-15 (2011).

9. Meyer, Y., Buchanan, B.B., Vignols, F., & Reichheld, J.P.Thioredoxins and glutaredoxins: unifying elements in redoxbiology. Annu Rev Genet 43, 335-67 (2009).

10. Meinnel, T.& Giglione, C. Protein lipidation meetsproteomics. Front Biosci 13, 6326-40 (2008).

11. Salaun, C., Greaves, J., & Chamberlain, L.H. The intracellulardynamic of protein palmitoylation. J Cell Biol 191(7), 1229-38 (2010).

12. Misaki, R. et al. Palmitoylated Ras proteins traffic throughrecycling endosomes to the plasma membrane duringexocytosis. J Cell Biol 191(1), 23-9 (2010).

13. Steelman, L.S. et al. Roles of the Raf/MEK/ERK and PI3K/PTEN/Akt/mTOR pathways in controlling growth and

25

sensitivity to therapy-implications for cancer and aging. Aging(Albany NY) 3(3), 192-222 (2011).

14. Zachary, I. VEGF signalling: integration and multi-taskingin endothelial cell biology. Biochem Soc Trans 31(Pt 6), 1171-7 (2003).

15. Burgoyne, J.R. et al. Oxidation of HRas cysteine thiols bymetabolic stress prevents palmitoylation in vivo andcontributes to endothelial cell apoptosis. FASEB J (2011).

16. Grines, C.L. et al. Angiogenic Gene Therapy (AGENT)trial in patients with stable angina pectoris. Circulation105(11), 1291-7 (2002).

17. Simons, M. et al. Pharmacological treatment of coronaryartery disease with recombinant fibroblast growth factor-2:double-blind, randomized, controlled clinical trial. Circulation105(7), 788-93 (2002).

18. Henry, T.D. et al. The VIVA trial: Vascular endothelialgrowth factor in Ischemia for Vascular Angiogenesis.Circulation 107(10), 1359-65 (2003).

19. Barton, M. Obesity and aging: determinants of endothelialcell dysfunction and atherosclerosis. Pflugers Arch 460(5),825-37 (2010).

Forthcoming Cardiovascular Meetings

XVI International Symposium on Atherosclerosis will be held in Sydney, Austrailia on March 25th-29th,2012. For further details please visit: http://www.isa2012.com/

Molecular Basis of Vascular Inflammation and Atherosclerosis (C7) March 25 - 30, 2012 • Big SkyResort • Big Sky, Montana. Further details and programme are available at: http://www.keystonesymposia.org/Meetings/ViewMeetings.cfm?MeetingID=1140

Frontiers in Cardiovascular Biology 2012 London, United Kingdom, on 30th March to 1st April 2012. Forfurther details see: http://www.escardio.org/congresses/cardiovascular-biology-2012/Pages/welcome.aspx

Ar teriosclerosis, Thr ombosis and Vascular Biology 2012 Scientific Sessions. Chicago Hilton, Chicago,IL, April 18-20, 2012. For details, please see: http://my.americanheart.org/professional/Sessions/ATVB/ATVB_UCM_316902_SubHomePage.jsp

The XXXIII Annual Meeting of the North American Section will be held May 28-31, 2012 in Banff, AB,Canada. Further details via http://www.ishrworld.org

Basic Cardiovascular Sciences 2012 Scientific Sessions, Hilton New Orleans Riverside, New Orleans, La.July 23-26, 2012. http://my.americanheart.org/professional/Sessions/BCVS/BCVS_UCM_316903_SubHomePage.jsp

ESC Congress 2012 will be in Munich, Germany, on 25 - 29 August 2012 http://www.escardio.org/congresses/esc-2011/Pages/Future-ESC-Congresses.aspx

Travel Reports for The BulletinThe Bulletin editors look forward to publishing travel reports written by BSCR members.

These can be on any conference, course or laboratory visit of interest to other members and

could perhaps contain photographs. If you are planning to travel to a relevant cardiovascular

meeting and would like to write a report for The Bulletin, please contact the editors before-

hand. A bursary of £300 is available towards the cost of your visit which will be provided

upon receipt of the report. Bon voyage!

26

Monday, 28th May

10.30 - 12.00 Functional Imaging Arrhythmogenic Substrates/Arrhythmias

Chairs Dr Andrew Grace and Prof Manuela Zaccolo

10:30 Cyclic nucleotide signalling: in vivo imaging of intracellular signal transductionProf Manuela Zaccolo (Glasgow)

10:50 Imaging structure and calcium release in the atriaDr Katherine Dibb (Manchester)

11:10 Exciting Light: Optogenetics in Cardiac Muscle PhysiologyDr Philipe Sasse (Bonn)

11:30 Imaging and Cardiac AblationDr Samuel Asirvatham (Rochester, MN)

11:50 Discussion

13.00 - 14.30 Application of imaging techniques in heart failure research

Chairs Prof Colin Berry and Prof Godfrey Smith

13:00 New nanoscale technique to study cAMP/cGMP localisation in cardiovascular tissueDr Julia Gorelik (London)

13:20 Local control in EC couplingDr Mark Cannell (Bristol)

13:40 Multi-photon imaging of contractile failureDr Rachel Myles (Glasgow)

14:00 Nox4-dependent protective effects in the heartProf Ajay Shah (London)

14:20 Discussion

Late Spring Meeting 2012

Joint meeting with the British Atherosclerosis Society at the BritishCardiovascular Society Annual Conference

“ New Frontiers in Cardiovascular Imagingfr om Basic Science to Clinical Application”

Manchester Central (Charter 1)

28th - 29th May 2012

27

15.00 - 16.30 BSCR/BAS Posters in the Fitzroy Atrium

17.30 - 18.30 John French Lecture

Matrix metalloproteinases and atherosclerosis: get the right balance

Dr Jason Johnson (Bristol) Chair Prof Martin Bennett

Tuesday, 29th May08.30 - 10.00 Joint BAS/BSCR Young Investigators Award

Chairs Prof Martin Bennett and Dr Yvonne Alexander

13.00 - 14.30 Molecular and cellular imaging in myocardial infarction andregeneration

Chairs Prof Robin Choudhury and Dr Farouc Jaffer

13:00 Elucidation of myocardial healing: lessons from multimodal imagingDr Matthias Nahrendorf (Boston)

13:40 MRI for comprehensive characterization in mouse models of myocardial ischemiaDr Jurgen Schneider (Oxford)

14:00 MR spectroscopy, oxygen imaging, myocardial metabolism and emerging techniquesProf Stefan Neubauer (Oxford)

14:20 Discussion

15.00 - 16.30 Emerging techniques for evaluation of atherosclerotic plaque

Chairs Dr Matthias Nahrendorf and Dr James Rudd

15:00 Near-infrared fluorescence approaches to imaging atherosclerosis and thrombosisDr Farouc Jaffer (Boston)

15:40 VH-IVUS in acute coronary syndromesProf Martin Bennett (Cambridge)

16:00 Application of positron emission tomography for the assessment of novel therapiesDr James Rudd (Cambridge)

16:20 Discussion

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Ireland), Karen Porter (Leeds, UK), Jurgen Schneider (Oxford, UK), Ajay Shah (London, UK), Nicola

Smart (Oxford, UK), Thomas Thum (Hannover, Germany).

ABSTRACT SUBMISSION: Four abstracts will be chosen for oral presentation and a prize awarded

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British Heart Foundation Grants

Project Grants Committee September 2011

Professor Richard J Evans, University of Leicester.Investigation of ligand sensitive conformational changesin cardiovascular P2X receptors with voltage-clampfluorometry. 3 years £175,476

Dr Simon R Clarke et al., University of Reading.Inhibition of platelet activation by Staphylococcusaureus lipoteichoic acid. 3 years £195,787

Professor Daniel Zehnder et al., University of Warwick.Improvement in left ventricular geometry andcardiovascular functional capacity after restitution of thefailing kidney through transplantation. A prospectivenon-randomised concurrent control study. 3 years£217,703

Professor David O Bates et al., University of Bristol.Molecular control of arteriolargenesis in peripheralischaemia. 3 years £193,178

Professor Harry Mellor, University of Bristol. The roleof VEGF receptor dimerisation in angiogenic signalling.1 year, 6 months £105,136

Dr Philip E James et al., Cardiff University. Cardiacmicrovascular function: assessment and protection duringcoronary intervention. 2 years £83,232

Professor John G McCarron et al., University ofStrathclyde. Imaging changes in mitochondrialarchitecture and mobility in vascular disease. 3 years£245,528

Professor Glenn Morris et al., Keele University. Nesprinisoforms and variants: their functions and roles in thepathogenesis of inherited cardiomyopathy. 3 years£193,450

Dr Lee Smith et al., University of Edinburgh. Cell-specific action of androgen receptor in cardiovascularfunction, response and repair. 3 years £298,051

Dr Branko Latinkic et al.,Cardiff University. Mechanismsof action of cardiogenic transcription factor GATA4. 3years £192,412

Professor Jonathan H Gillard et al., University ofCambridge. Towards a biomechanics-based vulnerabilityassessment tool for carotid atherosclerotic plaque:mechanical property testing and MRI-basedcomputational modelling. 3 years £193,818

Professor Timothy David Warner et al., Queen Mary,University of London. Exploiting synergies betweentherapeutic drugs and endogenous mediators to improve

anti-thrombotic therapy in patients with peripheral arterialdisease. 2 years £113,157

Professor Deborah J Henderson et al., University ofNewcastle upon Tyne. Vangl2 as a regulator of secondheart field movements into the heart. 3 years £264,796

Professor Sarah J George et al., University of Bristol.Involvement of Wnt-induced secreted protein-1 (WISP-1/CCN4) in atherosclerosis. 3 years £151,146

Dr Mark Bond et al., University of Bristol. Novel cAMP-dependent Epac-signalling pathways controlling VSMCproliferation. 3 years £209,807

Professor M-Saadeh Suleiman et al., University ofBristol. The cardioprotective efficacy of consecutivePKA & PKC activation in diseased heart. 3 years£236,038

Dr Neil A Turner et al., University of Leeds. Modulationof myocardial remodelling by fibroblast-selectiveinhibition of interleukin-1 signalling. 3 years £241,642

Dr Liming Ying et al., Imperial College London (NHLI).A new therapeutic approach based on small moleculeligands targeting DNA quadruplexes in the genes relatedto heart failure. 3 years £181,653

Dr Delyth Graham et al., University of Glasgow. Themitochondria-targeted antioxidant MITOQ10: a noveltherapeutic agent for cardiovascular disease. 1 year£59,721

Professor Costanza Emanueli et al., University of Bristol.Role of interleukin-33 (IL-33) and its ST2 receptor inpost-ischaemic vascular repair. 2 years £226,641

Professor Chris S Peers et al., University of Leeds.Modulation of T-type Ca2+ channels by hydrogensulphide: a novel pathway for regulation of vascularsmooth muscle proliferation. 3 years £197,609

Dr Heather Wilson et al., University of Sheffield. Controlof inflammation by Epithelial Membrane Protein-2: apotential vascular disease regulator. 2 years £104,939

Professor Robin J Plevin, University of Strathclyde.Using a novel MAP kinase phosphatase-2 mutant todifferentially regulate vascular smooth muscle cellproliferation and endothelial cell apoptosis. 2 years£112,862

Professor Alan J Williams et al., Cardiff University.Uncovering the mechanisms involved in the block of Ca2+

release from the cardiac sarcoplasmic reticulum byflecainide. 2 years £274,862

32

Fellowships Committee October 2011

Non-Clinical Fellowships

4 year PhD Studentships

Professor Martin R Bennett, University of Cambridge:3rd intake 2011 4 Year PhD Studentship Scheme: MrWilliam Bernard; Mr Alessandro Bertero; Ms LauraBurzynski; Ms Victoria Pell. 4 years £567,044

Dr Matthew Bailey, University of Edinburgh: 3rd intake2011 4 Year PhD Studentship Scheme: Ms SusanGallogly; Ms Jessica Ivy; Ms Rebecca Moorhouse; MsSana Maqsood. 4 years £523,840

Professor Anna F Dominiczak OBE, University ofGlasgow: 3rd intake 2011 4 Year PhD StudentshipScheme: Mr Christopher Lavery; Ms Kirsten Munro;Ms Katrin Nather; Mr Martin Wilson. 4 years £526,656

Professor Metin Avkiran, King’s College London: 3rdintake 2011 4 Year PhD Studentship Scheme: Ms JoannaFurmston; Mr Rajesh Mistry; Ms Hannah Tomlins; MsVesna Zuzel. 4 years £567,916

Dr Clare E Austin, University of Manchester: 3rd intake2011 4 Year PhD Studentship Scheme: Ms SamanthaBorland; Ms Charlotte Bussey; Ms Thomas Morris; MsMaria Pieri. 4 years £528,144

Dr David R Greaves, University of Oxford: 3rd intake2011 4 Year PhD Studentship Scheme: Mr ArneBruyneel; Mr Harrison Davis; Mr Drew Duglan; MrDaniel Regan-Komito. 4 years £572,116

Professor Peter J Scambler, University College London:3rd intake 2011 4 Year PhD Studentship Scheme: MrDaniel Dilg; Ms Bridget-Ann Kenny; Ms HannahNicholas; Dr. Denes Stefler. 4 years £571,196

PhD Studentships

Professor Harry Mellor, University of Bristol.Mechanisms of neovascularisation: the role of the novelcytoskeletal regulator DAAM2 in angiogenesis. 3 years£99,620

Professor Christopher W J Smith, University ofCambridge. Regulation of vascular smooth musclealternative splicing by core splicing factors. 3 years£102,025

Professor Jonathan Gibbins, University of Reading. Theregulation of platelet function and cell signalling by anewly identified platelet collagen receptor, the chaperoneprotein HSP47. 3 years £100,497

Professor Janice M Marshall, University of Birmingham.Mechanisms underlying the detrimental effects of ageingon cerebrovascular responses to rises in blood pressure.3 years £111,933

Dr Alun Coker, University College London. Cardiacamyloid; investigation of the role of serum amyloid Pcomponent in fibrillogenesis. 3 years £109,471

Clinical Fellowships

Clinical Research Leave FellowshipDr Guy A MacGowan, University of Newcastle. Cardiacenergetics and function in normal human ageing. 3 years£287,177

Clinical Research Training Fellowships

Professor Michael S Marber, King’s College London.The assessment of coronary blood flow and myocardialwork in patients with warm-up angina; increased flowor reduced need? 3 years £209,898

Dr Richard J Pease, University of Leeds. The role oftransglutaminases in the development of aortic abdominalaneurysms. 3 years £172,160

Dr Darrel P Francis, Imperial College London. CardiacResynchronisation Therapy: Does the haemodynamicimprovement of biventricular pacing truly arise fromcardiac resynchronisation? 3 years £190,442

Dr C Aldo Rinaldi, King’s College London. Assessmentof left ventricular grey zone using MRI to predictventricular arrythmias in patients with implantabledefibrillators. 2 years £144,318

Dr Richard Cubbon, University of Leeds. Can restorationof vascular endothelial insulin signalling rescue impairedendogenous vascular repair in systemic insulinresistance? 3 years £178,773

Cardiovascular RelatedWellcome Trust Grants

October to December 2011

Enhancement - Programme GrantProf Shah B J Ebrahim, Dept of Epidemiology & PopHealth, London School of Hygiene & Tropical Medicine.Genetic and epigenetic determinants of obesity anddiabetes in India. 12 months £198,000

Research Training FellowshipMiss Jennifer Ann Haworth, School of Oral and DentalSciences, University of Bristol. Mouth to Heart:Mechanism of Oral Bacteria-Induced PlateletActivation. 36 months £189,989

Research Career Development FellowshipDr Fiona McGillicuddy, Conway Institute, UniversityCollege Dublin. Functional consequences of obesity-induced adipose tissue inflammation on HDL acceptorcapacity and reverse cholesterol transport (RCT) 60months £647,419

Join us for BSCR/BAS 2012, showcasing the latest advances in our current understanding of

cardiovascular imaging and its potential for clinical application. This meeting addresses our

commitment to health care innovation and translation into improved patient well-being.

Joint British Society for Cardiovascular Research / British Atherosclerosis

Society

Spring Meeting 2012

with the British Cardiovascular Society

“New Frontiers in Cardiovascular Imaging from Basic

Science to Clinical Application”

Dates: Monday 28th and Tuesday 29

th May 2012

Venue: Manchester Central Conference Centre, Manchester

Organisers: Professor Colin Berry, Professor Robin Choudhury, Dr Andrew Grace, Dr James Rudd

Focus topics

• Molecular and cellular imaging in myocardial infarction and regeneration

• Emerging techniques for evaluation of atherosclerotic plaque

• Functional imaging of arrhythmogenic substrates and arrhythmias

• Application of imaging techniques in heart failure research

The programme consists of state-of-the-art presentations by leaders in the field including:

Manuela Zaccolo (Glasgow), Katherine Dibb (Manchester), Philippe Sasse (Bonn), Samuel J.

Asirvatham (Rochester, MN), Julia Gorelik (London), Mark Cannell (Bristol), Rachel Myles

(Glasgow), Ajay Shah (London), Matthias Nahrendorf (Boston), Jurgen Schneider (Oxford), Stefan

Neubauer (Oxford), Farouc Jaffer (Boston), Martin Bennett (Cambridge), James Rudd (Cambridge).

Free Communications: There will be oral presentations of selected abstracts, six of which will be selected for

the Joint BSCR/BAS Young Investigator Award. A poster prize provided by the BHF will also be awarded.

Student bursaries: The BSCR/BAS will consider awarding travel grants of up to £200 to bona fide students who

are BSCR members or who work in BAS members laboratories. Application forms are available from the BSCR

website (www.bscr.org).

Full programme details are available from the BSCR or BAS website (www.bscr.org,

www.britathsoc.org/) Enquiries may be addressed to the organisers, Andrew Grace

([email protected]), Colin Berry ([email protected]), James Rudd

([email protected]), and Robin Choudhury ([email protected])

the bulletin - bscr · 46 grafton st manchester. m13 9nt tel: +44 (0) 161 2751224 fax: +44 (0) 161...

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