induction of quinone reductase and heat shock protein 70 by some phytochemicals
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Abstracts / Toxico
nduction of quinone reductase and heat shockrotein 70 by some phytochemicals
hmed Hamed, Andrew Wilkinson, Waisun Kok,effrey Fry
School of Biomedical Sciences, Medical School,niversity of Nottingham, Nottingham NG7 2UH, UK
-mail address: mbxah@nottingham.ac.uk (A. Hamed).
Medicinal and edible plants have been considered asich sources of cancer-chemopreventive phytochemicalsnd there is a growing interest in identifying phytochem-cals which have multiple cytoprotective properties. In arevious report (Hamed and Fry, 2006), we have shownhe ability of sulforaphane (SN), a well-known chemo-reventive phytochemical, to induce heat shock protein0 (HSP70) and quinone reductase (QR) in rat (FGC4)nd murine (hepa1c1c7) hepatoma cell lines, respec-ively. The aim of this work is to test other QR-inducinghytochemicals (Curcumin (CM) and Indole-3-carbinolI3C); Kang and Pezzuto, 2004) for their potential mul-iple cytoprotective effects.
Cultured FGC4 and hepa1c1c7 cells were exposedo different concentrations of CM or I3C for 24 h afterhich cells were lysed and the cytosolic fraction pre-ared from these lysates. Toxicity of the phytochemicalsas tested in an identical set of experiments usingeutral red uptake assay to determine the maximumon-toxic dose for each phytochemical. QR activities inepa1c1c7 cell lysates were monitored kinetically usingichlorophenolindophenol (DCPIP) reduction assay.he effect of CM or I3C on the QR and HSP70 expres-ion was monitored by Western blotting using 10 �g totalrotein per lane.
As summarized in Table 1, SN produced a significantnduction of QR activity and expression in hepa1c1c7ells at non-toxic concentration of 25 �M. Also, thereatment of hepa1c1c7 cells with I3C (100 �M) and
able 1ffect of SN, I3C and CM on QR activity, QR expression and HSP70xpression (QR in hepa1c1c7 cells; HSP70 in FGC4 cells)
QR activity(%)
QR protein(%)
HSP70protein (%)
N (25/12.5 �M) 380 ± 20** 430 ± 143* 220 ± 19*
3C (100 �M) 260 ± 20** 210 ± 30* 72 ± 17M (25 �M) 260 ± 25** 256 ± 6* 77 ± 5
ata are means ± S.E.M. (% to relevant control) of at least three exper-ments. Where indicated, values in treated cells are significantly greaterhan those in control cells at *P < 0.05, **P < 0.01 (ANOVA, Dunnett’sest).
(2007) 164–192 171
CM (25 �M) revealed significant induction of QRactivity and expression. The treatment of FGC4 cellswith I3C and CM produced no increase of the expressionof HSP70 protein at non-toxic concentration whilsttreatment of FGC4 with SN (12.5 �M) elicited a signif-icant up-regulation of HSP70 expression. However, CMcaused a significant induction of HSP70 (220% ± 32,relevant to control) at the toxic concentrationof 100 �M.
The results indicate that the multiple cytoprotectiveeffects of SN are not matched by I3C and CM. The cellu-lar response to CM at 100 �M (up-regulation of HSP70)appears to be a consequence of its toxicity at this concen-tration. Further work will be directed towards elucidatingthe mechanism of HSP70 induction by SN, and towardsthe study of additional plant products for their potentialmultiple cytoprotective effects.
References
Hamed, A., Fry, J, 2006. Planta Med. 72, 1055.Kang, Y., Pezzuto, J.M., 2004. Methods Enzymol. 382, 380–414.
doi:10.1016/j.tox.2007.06.050
Comparison of gene expression changes in wholepancreas with isolated pancreatic acinar cells of ratsfed diets containing Wyeth 14,643 or ammoniumperfluorooctanoate
Simon M. Plummer 1, David G. Farrar 2, Clifford R.Elcombe 1
1 CXR Biosciences Ltd., James Lindsay Place, Dundee,UK; 2 Ineos Chlor, Runcorn, Cheshire, UK
E-mail address: simonplummer@cxrbiosciences.com(S.M. Plummer).
The non-genotoxin APFO (300 ppm in the diet) hasbeen shown to induce pancreatic acinar cell tumours inrats Biegel et al. (2001). In order to identify pancre-atic gene expression changes associated with pancreaticcarcinogenesis in ‘target’ cells for this process maleSprague–Dawley rats (6–7 weeks old) were fed either(1) the potent pancreatic carcinogen Wyeth 14,643(Wy) in the diet at 50 ppm (carcinogenic dose) or (2)APFO at 300 ppm for up to 4 weeks. Transcriptionalprofiling analysis at 1, 7 and 28 days, using a ratwhole genome 60 mer oligonucleotide array containing
∼44,000 genes was performed on purified preparationsof pancreatic acinar cells. Pancreatic acinar cells werepurified using a method involving collagenase digestionand centrifugation through BSA (10%). Immunohis-top related