Application of in the world_Steroids 2.0.pptx

Medical education

1. STEROIDS

2. Steroids form an important group of compounds based on the fundamental saturated tetracyclic hydrocarbon: 1,2-cyclopentanoperhydrophenanthrene ( sterane or gonane ). The term " steroids " was coined by Callow RK et al. (Proc Royal Soc London series A 1936, 157, 194) "for the group of compounds comprising the sterols, bile acids, saponins and sex hormones". INTRODUCTION

3. The sterols, bile acids, heart poisons, saponins and sex hormones have number of functions in human physiology and are of immense biological importance. Cholestrol – 200g per average adult Found in plants, animals and fungi All steroids are made in cells from sterols Lanosterols – Animals and fungi Cyclosterols - Plants Both lanosterols and cyclosterols are derived from cyclization of the triterpene squalene .

4. Sterols Brassinosteroids Bufadienolides Cardenolides Cucurbitacins Ecdysteroids Sapogenins Steroid alkaloids Withasteroids Bile acids Hormonal steroids According to their chemical structure, the wide array of steroid molecules may be divided into several groups : CLASSIFICATION

5. Sterols form an important group among the steroids STEROLS Sterols such as stigmasterol and sitosterol are essential components of cell membranes and they are also used as the starting material in the production of steroidal drugs. Phytosterols are minor but beneficial components of the human diet since they may inhibit growth of tumours and help in regulation of blood cholesterol. Therapeutically they are important constituents of the various herbs Withania somniferum , Commiphora mukul etc.

6. BRASSINOSTEROIDS Brassinolide - isolated from the pollen of Brassica napus in 1979 is brassinolide exhibits the highest biological activity of the known brassinosteroids . are potent plant growth and development regulators, dozens of compounds of similar structure were isolated from plant sources (algae, ferns, gymnosperms and angiosperms, but not bacteria) or synthesized.  It was shown that they interact with jasmonates in the formation of anti- herbivory traits in tomato

7. They have been isolated from plants and animals. More than 250 compounds have been identified. BUFADIENOLIDES In plants, they are mostly glycosides with one to three sugars in a chain linked to the 3-hydroxyl group. They are important for their cardiotonic activity. Furthermore, they possess insecticidal and antimicrobial properties, those produced by the toad skin are strongly poisonous. Family Liliaceae , Bowiea and Scilla

8. Monarch butterfly is well known to be highly toxic to birds because of cardenolides which come from the milkweed leaves eaten by its caterpillar. Experimentally, the larvae of the lepidopteran - Trichoplusiani were poisoned by feeding on the milkweed Asclepias curassavica . CARDENOLIDES They are widely distributed in plants mainly as glycosides and are either toxic or insect deterrents. As potent cardiotonics , these steroids were largely studied ( digoxin and its derivative).

9. Mammals perceived these toxic molecules as some of the bitterest substances known. CUCURBITACINS These steroids which are commonly combined in glycosides, are mainly associated with Cucurbitaceae species but they have also been detected in other families. Cucurbitacins have been shown to act as ecdysteroid receptor antagonists.

10. The most common phytoecdysteroid in plants is ecdysone (20Ehydroxyecdysone). ajugalactone jn Ajuga reptans , Cyasterone , makisterone B in A. chamaepitys ( Labiatae ), ajugasterone C in Vitex madiensis ( Verbenaceae ), inokosterone in Achyranthes fauriei ( Amaranthaceae ), ponasterone A in Podocarpus nakaii ( Podocarpaceae ).  ECDYSTEROIDS Ecdysteroids are present both in animals and plants. In plants, they are named " phytoecdysteroids " and they seem to protect plants against most insects. Insects that ingest phytoecdysteroids and are not adapted to this defense are subject to serious adverse effects, including reduced weight, molting disruption and/or mortality.

11. They are extremely distributed in plants since they occur in over 90 plant families. They are used in nutrition, as herbal medicine, and in cosmetics. SAPOGENINS These steroids can mimic or regulate steroid hormones. Thus, diosgenin can be chemically converted into corticosteroids, estrogens and progesterone. Glycyrrizin - liquorce roots – antiinflammatory activity Antifungal, antimicrobial, adaptogen .

12. These alkaloids are only distributed in Solanaceae (potato, tomato, eggplant ...). Fortunately, their toxic properties disappear by structural transformation during ripening. Solasodine is the most common species in Solanum . STEROID ALKALOIDS

13. Over 200 species are known, some of them as glycosides. They are predominantly associated with Solanaceae but are also found in other families ( Taccacceae , Leguminosae , Labiatae ). WITHASTEROIDS Withanolides are known to have important pharmacological properties (anti-tumor, immunosuppressive) but they are also antimicrobial, insect deterrent or ecdysteroid receptor antagonists.

14. BILE ACIDS The end products of cholesterol utilization are the bile acids.

15. The most abundant bile acids in human bile are chenodeoxycholic acid (45%) and cholic acid (31%). These are referred to as the primary bile acids. secondary bile acids, identified as deoxycholate (from cholate ) and lithocholate (from chenodeoxycholate ). Bile acids have long been known to be essential in dietary lipid absorption and cholesterol catabolism.

16. This large group can be divided into three major families, mainly on the basis of their physiological function or their tissue origin : HORMONAL STEROIDS Sexual hormones Corticosteroids Neurosteroids

17. This important group may be again divided into estrogens, gestrogens and androgens. SEXUAL HORMONES Estrogens – Ovarian hormones Eg . Sprouting Oat seeds, garlic, tulip bulbs. G estrogens – Corpus luteum hormones Isolated from Corpus luteum , adrenal cortex, Ovaries and placenta Androgens – Male hormones Occur in mammalian organisms Are produced mainly by the adrenal cortex, testes and ovaries These are chiefly metabolised by the liver and excreted in urine as conjugates of glucuronic or sulphuric acid.

18. C orticoids - formed in the adrenal cortex. CORTICOSTEROIDS Corticosteroid hormones in vertebrates are critical for metabolism, growth, reproduction, immunity and ion homeostasis and are an important part of the coping mechanisms involved in the stress responses

19. NEUROSTEROIDS The term " neurosteroid ", proposed by EE Baulieu in 1981, applies to steroids which are accumulated in the brain independently of supply by peripheral endocrine glands and which are synthesized from cholesterol in the nervous system. Several steroids have been described in the brain since the first report in 1981 of dehydroepiandrosterone (DHEA) and its sulfated derivative in the rat brain. Among the best known are pregnenolone , progesterone, allopregnanolone and DHEA.

20. Recent discoveries have revealed that brain is a site of extensive steroid metabolism and also a target of steroid hormones. These hormones play an important role in the development, growth, maturation and differentiation of the brain.

21. The N-methyl-D- aspartate   receptor  (also known as the  NMDA receptor  or NMDAR), is a glutamate  receptor  and ion channel protein found in nerve cells.

22. Withania somniferum ( Solanaceae ), known as ashwaganda in Ayurvedic medicine, contains steroidal lactones called withanolides which exhibit antitumour and hepatoprotective activities. Powerful drugs that many people use as a short cut to boost their athletic performance or improve their appearance. In Commiphora mukul —myrrh (known as guggal in India)—the resin contains steroids known as guggulsterones , which lower blood cholesterol and triglycerides via stimulation of thyroid function. USES/APPLICATIONS

23. THANK YOU….