a seminar on,hormon receptor

By, Sanket J. Gandhi

M. PHARM (I s t SEM) Department of Pharmacology

R.C. Patel Institute Of Pharmaceutical education and Research

HORMONAL RECEPTORS

IndexIntroduction to

Hormone 3,4

Slide No.

Hormonal receptor 5,6

Cell surface receptor 7-16

Nuclear receptor 17-29

Cell surface receptor description

30-43

Nuclear receptor description

44-51

Recent advances 52,53

References 54,55 2

INTRODUCTION TO HORMONE A Hormone is any member of a class of signaling molecules produced by glands in

multicellular organisms that are transported by the circulatory system to target distant organs to regulate physiology and behaviour.

Hormones effects on the body:

Stimulation or inhibition of growth

Sexual arousal

Induction or suppression of apoptosis and to control puberty and menopause

Activation or inhibition of the immune system 3

Norman, Anthony W., and Gerald Litwack. Hormones. Academic Press, 1997.

Regulation of metabolism

Control of the reproductive cycle

Hormones exert their actions as:

1.Endocrine action

2.Paracrine action

3.Autocrine action

INTRODUCTION TO HORMONE

4


Hormone receptors have two mandatory characteristics: The receptor must identify a unique binding site within the hormone.

The receptor must be able to transmit the signal caused by binding with the hormone into a cellular response.

HORMONAL RECEPTORS

5


Hormonal receptors

Intercellular(nuclear) receptors

steroidal hormone receptors:

1)Glucocorticoid H. R. 2)Mineralocorticoid H. R. 3)Androgen H. R. 4)Estrogen H. R. 5)Progesteron H. R.

Thyroid hormone(T3and T4) receptor

Cell surface(plasma membrane) receptors

Examples:1)FSH and LH R.2)Insulin H. R.3)Growth H. R.4)Oxytosin and ADH R.5)Catecholamines H. R.Etc.

CLASSIFICATION OF HORMONALRECEPTORS

6

Giguère, Vincent, et al. "Identification of a new class of steroid hormone receptors." (1988): 91-94.

Structure of Cell Surface Receptors:

Cell surface receptors are integral membrane proteins, have regions that contribute to three basic domains:

Extracellular domains:

Transmembrane domains:

Cytoplasmic or intracellular domains:

CELL SURFACE RECEPTORS

7

Deller, Marc C., and E. Yvonne Jones. "Cell surface receptors." Current opinion in structural biology 10.2 (2000): 213-219.

Cell surface receptors hormones can show theirs action via 2 different pathways by activating various sec. messengers systems which are,

1) G-Protein couple receptor(GPCR) pathway.1. cAMP sec.messenger 2. calcium or phosphoinositide sec.messenger

2) Tyrosine kinase receptor pathway.

MECHANISMS OF CELL SURFACE RECEPTORS

8

Deller, Marc C., and E. Yvonne Jones. "Cell surface receptors." Current opinion in structural biology 10.2 (2000): 213-219.

1)GPCR PATHWAY1.CAMP SEC.MESSENGER ACTIVATION

9

Epinephrine and Norepinephrine

Glucagon

Luteinizing hormone, Follicle stimulating hormone

Thyroid-stimulating hormone,Calcitonin,Parathyroid hormone

Antidiuretic hormone

EXAMPLES OF HORMONES ACT THROUGH SUCH PATHWAY

10

1)GPCR PATHWAY

2.CALCIUM OR PHOSPHOINOSITIDE SEC.MESSENGER

11

Epinephrine and norepinephrine

Angiotensin II

Antidiuretic hormone

Gonadotropin releasing hormone

Thyroid-releasing hormone


12

Protein Tyrosine kinase Protein tyrosine kinases (PTKs) are a large family of enzymes that play critical roles in signal transduction. Through transferring γ-phosphate group from ATP to protein substrates, PTKs regulate functions of these substrates. Dimerization A dimer is a macromolecular complex formed by two, usually non-covalently bound, macromolecules such as proteins or nucleic acids. It is a quaternary structure of a protein. When two monomers get attached to each chemically and form dimer then its called dimerization.

2.TYROSINE KINASE PATHWAY

13

Schlessinger, Joseph. "Cell signaling by receptor tyrosine kinases." Cell 103.2 (2000): 211-225.

2.TYROSINE KINASE PATHWAY

14

Dimerization activates the kinase activity and leads toautophosphorylation, creating sites for interactions withspecific effectors. Ras A key component of the RTK cascade is Ras Ras is small, monomeric G protein with very low

GTPase activity.

Grb2 SH2 protein that binds to phosphorylated RTKs It has three domains, one binds the RTK, the other Binds Sos

Sos It is a Ras-GEF. When recruited to the membrane it

activates Raf

Raf Ras-GTP recruits Raf, which becomes activated as a

protein kinase and initiates the MAP kinase cascade 15

Insulin

Growth hormone

Prolactin

Oxytocin

Erythropoietin

Several growth factors


16

Nuclear receptors are intracellular proteins expressed in the nucleus of a cell.

Nuclear receptors are a family of ligand-regulated transcription factors that are activated by steroid hormones, such as estrogen and progesterone, and various other lipid-soluble signals, including retinoic acid, and thyroid hormone.

Nuclear receptors (NRs) are proteins that share considerable amino acid sequence similarity in two highly conserved domains.

DNA binding (DBD) and the ligand binding domains (LBD).

NUCLEAR RECEPTORS

17

Freedman, Leonard P. "Increasing the complexity of coactivation in nuclear receptor signaling." Cell 97.1 (1999): 5-8.

NUCLEAR RECEPTORSNuclear receptor

super family

Class 1 steroid receptor family 1.Estrogen

receptor2.Androgen receptor3.Progesteron receptor4.Minerelocortocoid receptor5.Glucocorticoid receptor

1.Thyroid receptor2.Retinoicacid receptor3.VitamineD receptor4.Peroxisome proliferator activated receptor

Class 2 receptor familyClass 3 receptor family

Orphans type of receptors1.Farnesoicx receptor2.Liver x receptor

18

Mangelsdorf, David J., et al. "The nuclear receptor superfamily: the second decade." Cell 83.6 (1995): 835-839.

Basic components related to nuclear receptor:

Zinc fingers: Zinc fingers have one or more zinc atoms gripped by a combination of four amino acids, either cysteine or histidine. a protein can grab a zinc ion and fold tightly around it. a short chain of 20-30 amino acids is enough to create a solid, stable structure. Many zinc fingers play essential roles in DNA recognition and essential role in the development of blood cells.

NUCLEAR RECEPTORS

19

Nolte, Robert T., et al. "Differing roles for zinc fingers in DNA recognition: structure of a six-finger transcription factor IIIA complex." Proceedings of the National Academy of Sciences 95.6 (1998): 2938-2943.

Heat shock proteins (HSP):

Are a family of proteins that are produced by cells in response to exposure to stressful conditions such as infection, inflammation, exercise, exposure of the cell to toxins (ethanol arsenic, tracemetals and ultraviolet light), starvation, hypoxia.

Heat-shock proteins are named according to their molecular weight. For example, Hsp60, Hsp70 and Hsp90 (Chaperones).

Heat Shock Proteins bind to denatured proteins to prevent aggregation.

NUCLEAR RECEPTORS

20

Freedman, Leonard P. Molecular biology of steroid and nuclear hormone receptors. Springer Science & Business Media, 1998.

Coactivator and Corepressor: Transcription coregulators that activate gene transcription are referred to as coactivators while those that repress are known as corepressors. The mechanism of action of transcription coregulators is to modify chromatin structure and thereby make the associated DNA more or less accessible to transcription.

NUCLEAR RECEPTORS

21

Petkovic, Martin, et al. "A human retinoic acid receptor which belongs to the family of nuclear receptors." Nature 330.6147 (1987): 444-450

A hormone response element (HRE) is a short sequence of DNA within the promoter of a gene that is able to bind a specific hormone receptor complex and therefore regulate transcription. HRE responds to steroid hormones, as the activated steroid receptor is the transcription factor binding HRE.

NUCLEAR RECEPTORS

sequence of DNA

Actual mechanism

22

Umesono, Kazuhiko, et al. "Direct repeats as selective response elements for the thyroid hormone, retinoic acid, and vitamin D 3 receptors." Cell 65.7 (1991): 1255-1266.

NUCLEAR RECEPTORS

A/B region

C region

D region

E region

F region 23

Moras, Dino, and Hinrich Gronemeyer. "The nuclear receptor ligand-binding domain: structure and function." Current opinion in cell biology 10.3 (1998): 384-391.

https://en.wikipedia.org/wiki/File:Nuclear_Receptor_Structure.png

NUCLEAR RECEPTORS

DNA-binding domain (DBD):

Highly conserved domain containing two zinc fingers that binds to specific sequences of DNA called hormone response elements (HRE).

Zinc atoms

Double strained DNA

DNA-binding domain dimer 24

NUCLEAR RECEPTORS Ligand binding domain (LBD): The structure of the LBD is referred

to as an alpha helical sandwich fold in which three anti parallel alpha helices are flanked by two alpha helices on one side and three on the other. The ligand binding cavity is within the interior of the LBD and just below three anti parallel alpha helical sandwich "filling“.

Crystallographic structure of the ligand binding domain of the human RORγ (rainbow colored, N-terminus = blue, C-terminus = red) complexed with 25-hydroxycholesterol (space-filling model (carbon = white, oxygen = red) and the NCOA2 coactivator (magneta).

25

MECHANISMS OF NUCLEAR RECEPTORS1)MECHANISM OF CLASS I NUCLEAR RECEPTOR ACTION

26

Steroid hormone receptors:

Glucocorticoid Receptor

Mineralocorticoid Receptor

Androgen Receptor

Estrogen Receptor

Progesterone Receptor

EXAMPLES OF HORMONES ACT THROUGH SUCH MECHANISM

27

MECHANISMS OF NUCLEAR RECEPTORS2)MECHANISM OF CLASS II NUCLEAR RECEPTOR ACTION

28

Retinoic acid receptor

Retinoid X receptor

Thyroid hormone receptor

EXAMPLES OF HORMONES ACT THROUGH SUCH MECHANISM

29

Steroid hormone receptors:

Glucocorticoid Receptor

Androgen Receptor

Estrogen Receptor

Progesterone Receptor

Thyroid hormone receptor:

NUCLEAR RECEPTORS DESCRIPTION

30

History of glucocorticoid receptor:

Glucocorticoid receptor (GR) drug discovery was initiated by adrenal gland extracts.

In 1948 sufficient quantities of cortisone could be purified and its effects in inflammatory disease could be tested. Finally, total syntheses of cortisone were independently achieved by R.B.Woodward.

GLUCOCORTICOID RECEPTOR

31

Rousseau, Guy G., John D. Baxter, and Gordon M. Tomkins. "Glucocorticoid receptors: relations between steroid binding and biological effects." Journal of molecular biology 67.1 (1972): 99-115.

Agonist Antagonist

Cortisol Mifepristone

Corticosterone Org 34850

Aldosterone RU-486


The GR is expressed in a wide variety of lymphoid cells, including T and B cells, and macrophages.

32

Role of Glucocorticoid Receptor In Disease Condition :

Inflammatory and immune disease Asthma therapy Allergic Reaction Myasthenia Gravis Infective Disease Hypercalcaemia


33

Androgens act via the AR and play an important role in the development

and differentiation of the male sexual organ.

It is also important in maintaining skeletal muscle mass and strength, BMD,

hematopoiesis.

The two natural occurring androgens are testosterone (T) and the

more potent 5α-dihydrotestosterone (DHT).

ANDROGEN RECEPTOR

34

Drews, Jürgen. "Drug discovery: a historical perspective." Science 287.5460 (2000): 1960-1964.

Role of Androgen Receptor In Disease Condition Hypogonadism

Anaemia

Osteoporosis

ANDROGEN RECEPTOR

Agonist Antagonist Synthetic progestin FlutamideDihydrotestosterone Spironolactone

Testosterone Danazol

35

History of estrogen receptor:

Estrone was isolated in 1929 as the first natural estrogenic hormone independently by the chemists E. A. Doisy and A. Butenand from the urine of pregnant women

In 1938, H. H. Inhoffen achieved for the first time the synthesis of estradiol from cholesterol.

The first synthesis of ethinyl-estradiol,which has an improved oral bioavailability, was published in 1938 by H. H. Inhoffen and W. Hohlweg.

ESTROGEN RECEPTOR

36

Drews, Jürgen. "Drug discovery: a historical perspective." Science 287.5460 (2000): 191964.

Both ERs are widely expressed, although ERα is more abundant in breast, endometrial, ovarian, and hypothalamus tissues, whereas ERβ is more abundant in brain, bone, endothelial, heart, intestine, kidney, lung, and prostate tissues.

ESTROGEN RECEPTOR

Agonist AntagonistEstradiol TamoxifenEstrone DoloxifenEstriol Toremifen

Clomiphene Raloxifene37

History of progesterone receptor:

The observation that progesterone prevented ovulation was taken up by Haberlandt who was able to demonstrate that it could be used for fertility control.

In 1955, Gregory Pincus demonstrated that large doses of orally Administered progesterone inhibited ovulation in women.

Inhoffen had discovered in 1938 that 17a-ethynyl-testosterone was a weakly active progestin when administered orally.

PROGESTERONE RECEPTOR

39

Drews, Jürgen. "Drug discovery: a historical perspective." Science 287.5460 (2000): 1960-1964.

The PR is involved in diverse functions in female reproduction

Progesterone is mainly produced in the corpus luteum, placenta

The PR is expressed in the uterus, ovary.

Role of Progesterone Receptor In Disease Condition: Contraception

Hormone Replacement Therapy

Breast Cancer

Endometrial Hyperplasia

PROGESTERONE RECEPTOR

40

The thyroid hormones (THs) triiodothyronine (T3) and thyroxine (T4) bind to and activate the nuclear thyroid receptors TRα and TRβ.

Studies dating back to the 19th century showed that transplantation of sheep thyroid gland tissue could rapidly improve the state of a patient suffering from hypothyroidism.

Differential binding activity of THα and THβ could be shown among various tissues, with high binding in the liver, kidney, pituitary gland, heart, and brain.

THYROID HORMONE RECEPTOR

41

Shibata, Hirotaka, et al. "Role of co-activators and co-repressors in the mechanism of steroid/thyroid receptor action." Recent Progress in Hormone Research 52 (1996): 141-64

Actions of Thyroid Hormone Receptor Growth and Development

Calorigenic Effects

Cardiovascular Effects

Metabolic Effects

Thyroid Hypofunction

Thyroid Hyperfunction


42

Disorders of the thyroid gland Hyperthyroidism—excess of thyroid hormone production.

Hypothyroidism—deficiency of thyroid Hormone production.

Goitre formation.

Adenoma (benign growths) of the thyroid.

Carcinoma of the thyroid.


43

Shibata, Hirotaka, et al. "Role of co-activators and co-repressors in the mechanism of steroid/thyroid receptor action." Recent Progress in Hormone Research 52 (1996): 141-64.

Growth hormone receptor

Insulin receptor

Vasopressin receptor

CELL SURFACE RECEPTORS DESCRIPTION

44

Growth hormone was identified in the 1920s as a growth promoting Factor.

By mid to late 1980s scientists were able to produce this 191-residue protein hormone in bacteria using recombinant DNA technology.

Growth hormone is a protein hormone of about 190 amino acids that is synthesized and secreted by cells called somatotrophs in the anterior pituitary.

GROWTH HORMONE RECEPTOR

45

GROWTH HORMONE RECEPTOR When two receptors are brought together, interaction between the portions inside the cell triggers several enzymatic reactions and signaling processes that stimulate growth.

Thus formation of this receptor dimer is crucial for growth hormone function.

46

To regulate normal growth and development of body. Metabolic Effects Protein metabolism: Fat metabolism: Carbohydrate metabolism:

Role of Growth hormone in Disease States . Gigantism Acromegaly

GROWTH HORMONE RECEPTOR

47

INSULIN RECEPTOR

Insulin receptor visualised by electron microscope in frozen hydrated state(top) and its illustration(bottom)

Structure of Insulin receptor48

INSULIN RECEPTOR

49

VASOPRESSIN RECEPTORDistribution and signaling pathway of vasopressin

receptor.RECEPTOR SIGNALING PATHWAY LOCATION

V1(V1A) G protein couple/phosphatidylinositol

calcium

Vascular smooth muscle, platelet,

Hepatocytes and myometrium.

V2 Adenylyl cyclase/cAMP Basolateral membrane of collecting duct and vascular

smooth muscle cell.

V3(V1B) G protein couple/phosphatidylinositol

calcium

Anterior pituitary gland.

50

Jagadeesh, J. S., Muthiah, N. S., & Muniappan, M. (2014). Vasopressin Receptors and Drugs: A Brief Perspective. Global Journal of Pharmacology,8(1), 80-83.

Functions of vasopressin receptor Vasoconstriction Myocardial hypertrophy Platelet aggregation Glycogenolysis Uterine contraction Insertion of AQP-2 water channels into apical membrane Releases ACTH, prolactin, endorphins

VASOPRESSIN RECEPTOR

51

1)The concentration of the estrogen binding protein in the rat uterus has been studied in three stages of uterine development. A 3- to 4-fold increase in concentration of estrogen binding protein occurs between days one and ten after birth.

After estrogen is injected, the receptor concentration in the cytoplasm goes into a three-stage cycle.

(1) Initially, there is a loss of binding protein, followed by (2) a stage sensitive to inhibitors of protein and RNA synthesis, and (3) a replenishment period that is not affected by the inhibitors

RECENT ADVANCES

52

Gorski, J., M. Sarff, and J. Clark. "The regulation of uterine concentration of estrogen binding protein." (1971).

2)Bisphosphonates (BPs) have become the standard therapy for breast cancer patients with bone metastasis. It is now clear that the bisphosphonates reduce both the symptoms and complications of bone involvement

The administered bisphosphonates (BPs) differed according to the periods of treatment, compliance, tolerability and insurance strategy. The types of bisphosphonate used were zoledronate or pamidronate. These drugs were given at three or four week intervals.

RECENT ADVANCES

53

Park, In H., et al. "Potential antitumor effects of nitrogen-containing bisphosphonate in hormone receptor negative breast cancer patients with bone metastases." BMC cancer 9.1 (2009): 154.

Norman, Anthony W., and Gerald Litwack. Hormones . Academic Press, 1997 Giguère, Vincent, et a l . " Identification of a new class of steroid hormone receptors." (1988): 91-94. Del ler, Marc C., and E. Yvonne Jones. "Cel l surface receptors." Current opinion in structural bio logy 10.2

(2000): 213-219. Schlessinger, Joseph. "Cel l s ignal ing by receptor tyrosine kinases." Cell 103.2 (2000): 211-225. Freedman, Leonard P. " Increasing the complexity of coact ivat ion in nuclear receptor signal ing." Cell 97.1

(1999): 5-8. Mangelsdorf, David J . , et al . "The nuclear receptor superfamily: the second decade." Cell 83.6 (1995):

835-839. Nolte, Robert T., et al . "Differing roles for z inc fingers in DNA recognit ion: structure of a six-finger

transcription factor I I IA complex." Proceedings of the National Academy of Sciences 95.6 (1998): 2938-2943.

Petkovic, Martin, et al . "A human retinoic acid receptor which belongs to the family of nuclear receptors." Nature 330.6147 (1987): 444-450

Umesono, Kazuhiko, et a l . "Direct repeats as select ive response elements for the thyroid hormone, retinoic acid, and vitamin D 3 receptors." Cell 65.7 (1991): 1255-1266.

Moras, Dino, and Hinrich Gronemeyer. "The nuclear receptor l igand-binding domain: structure and funct ion." Current opinion in cel l bio logy 10.3 (1998): 384-391.

Rousseau, Guy G., John D. Baxter, and Gordon M. Tomkins. "Glucocorticoid receptors: relations between steroid binding and biological effects." Journal of molecular bio logy 67.1

Drews, Jürgen. "Drug discovery: a historical perspect ive." Science 287.5460 (2000): 1960-1964. Shibata, Hirotaka, et al . "Role of co-activators and co-repressors in the mechanism of steroid/thyroid

receptor action." Recent Progress in Hormone Research 52 (1996): 141-64

REFRENCES

54

Jagadeesh, J . S., Muthiah, N. S. , & Muniappan, M. (2014). Vasopressin Receptors and Drugs: A Brief Perspective. Global Journal of Pharmacology ,8(1), 80-83

Gorski , J . , M. Sarff, and J . Clark. "The regulation of uterine concentration of estrogen binding protein." (1971).

Park, In H., et a l . "Potential antitumor effects of nitrogen-containing bisphosphonate in hormone receptor negative breast cancer patients with bone metastases." BMC cancer 9.1 (2009): 154.

REFRENCES

55

a seminar on,hormon receptor

Health & Medicine