plant steriods

1. Plant
Steroides
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2. STEROIDS
Steroids may be defined as:
 “Any of numerous naturally occurring or synthetic fat
soluble organic compounds having as a basis 14
Carbon atoms arranged in four rings. They include
sterols, bile acids, adrenal and sex hormones, certain
natural drugs such as Digitalis compounds and
precursors of certain vitamins.”
 “A steroid is any compound that contains a
cyclopentanoperhydrophenanthrene nucleus.”
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3. The diversity of biologic activities of
steroids includes;
Plant steroids:
 Plant steroids are natural products which influence
the development and control of the reproductive
tract in humans(estradiol, progesterone,
testosterone)
 The molting of insects (ecdysone)
 The induction of sexual reproduction in aquatic
fungi.
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4. In additions, steroids contribute to a wide
range of therapeutic applications, such as;
 Cardiotonics (digitoxin)
 Vitamin D precursors (ergosterol)
 Oral contraceptive agents (semisynthetic estrogens
and progestins)
 Anti-inflammatory agents (corticosteroids)
 Anabolic agents (androgens)
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5. Plant Sterols:
 Sterols, also known as steroid alcohols, are a
subgroup of the steroids
 Steroidal alcohols C27 – C29 are present in the lipid
fraction of many tissues. These are solids therefore
named as sterols. The most widely occurring sterol is
cholesterol. It has been identified in algae, fungi,
bacteria, ferns, animals and higher plants.
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6. Different Plant Steroids:
Cardiac Glycosides:
Some steroids present in nature are characterized by highly
specific and powerful actions that they exert on cardiac muscles.
These steroids occur as glycosides with sugars attached at
position 3 of steroid nucleus.
For example:
 Gitoxigenin.
 Gitaloxigenin.
 Digitoxigenin.
 Digoxigenin.
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7. Steroidal Aglycones or Genins:
The steroidal aglycones or genins are of two types:
Cardenolides:
The more prevalent in nature are the cardenolides which are C23
steroids. For example Digitalis, strophanthus.
Bufadienolides:
The bufadenolides are C24 homologs of Cardenolides. For
example White squill and Red squill.
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8. Bufadienolide.
Cardenolide
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9. Digitalis:
Botanical origin: Digitalis purpurea
Part used: dried leaves.
Family: Scrophulariaceae
Constituents: The drug contains a large number of steroidal
glycosides (neaely 30) of which the most important from medicinal
point of view are Digitoxin, Gitoxin, Gitaloxin.
Uses:
Digitalis is used in the form of tablets or capsules to treat congestive
heart failure, supraventricular tachycardia, atrial flutter and atrial
fibrillation.
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10. Digitalis lanata:
Constituents:
Nearly 70 glycosides have been detected from digitalis
lanata. They conatain derivatives of five different
aglycones three of which i.e digitoxigenin, gitoxigenin,
and gitaloxigenin also occur in digitalis purpurea. The
two other derivatives not found in digitalis purpurea
are digoxin and Lanatoside C.
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11. Oubain:
Botanical Origin: Strophanthus gratus
Part used: Dried ripe seeds.
Family: Apocynaceae
Constituents: It contains Oubain which is a glycoside
of oubagenin and rhamnose.
Uses:
 Most rapidly occurring cardiac glycoside
 used in the treatment of cardiac failure
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12. Squill:
Botanical origin: Urginea maritime
Part used: Dried fleshy inner scales of bulb.
Family: Liliaceae
Constituents: Scillaren A, glucoscillaren A, Proscillaridin
A, Rhamnose, Scillarenin
Uses:
Used as expectorant, diuretic, cardiotonic, rodenticide
and emetic property
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13. Steroidal saponins:
 Steroidal saponins are of great pharmaceutical importance
because of their relationship to compounds such as sex
hormones , cortisone, diuretic steroids, vitamin D and cardiac
glycosides. Some are used as starting materials for the
synthesis of these compounds.
 The glycosides which when shaken with water, produce
persistent froth, are called saponin glycosides, Aglycone part
of a saponin glycoside is called ‘sapogenin’
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14. Example: Ginseng
Steroidal Alkaloids:
Steroidal alkaloids arise by inclusion of a basic nitrogen at some point
in the steroid molecule.
Example: Veratrums:
Steroidal alkaloidal glycosides:
They are particularly abundant in the families solanaceae and liliaceae.
Like saponins they have hemolytic properties. Examples are :
Solanin(potato;solanum tuberosum).
Tomatin( tomato;lycopersicon esculentum)
Rubijervine. (veratrum spp.)
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15. Other steroids:
Withanolides:
This class of steroidal lactones involves an ergostane
type framework in which C-22 and C-26 are appropriately
oxidize to form a δ-lactone ring.
In 1968, Israeli workers determined the structure of a
constituent lactone (withaferin A) of the plant
Uses: Sedatives, hypnotics, antiseptics, antimitotic and
antitumor agents
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16. Botanical origin: Withania somnifera
Family: Solnaceae
Constituents: The constituents have been divided into 9
groups of which the withanolides are of wide therapeutic
importance
Since then many more compounds of this now large
class, have been characterized.
9 groups; Withanolides, Withaphysalins, Physalins,
Nicandrenones, Jaborols, Ixocarpalactones,
Perulactones, Acnistins and Miscellaneous withasteroids
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17. Ecdysones:
Ecdysones or insect molting hormones are substances which
stimulate the transformation of larvae into an adult. Ecdysone was
first isolated from silk-worm pupae.
Only a few such compounds have been isolated from arthropods,
but in plants they occur in much greater variety and abundance
Ecdysterone is also an example which has been isolated from both
plant and insect sources.
Whether a plant-insect relationship exists with regard to this
substance and whether such compounds have a function in the
plant, is at present not known
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18. It is perhaps significant, however, that insects do not themselves
biosynthesize steroids de novo and rely on plant materials for suitable
precursors
In the plant, cholesterol is a precursor of insect molting hormones,
and in one morphological group of Helleborus they are formed
together with bufadienolides and saponins
Cucurbitacins: They occur in Cucurbitaceae, Euphorbiaceae and
Cruciferae Family.
These tetracyclic triterpenoids are of interest because of their
cytotoxic and antitumour properties. Cucurbitacin may occur in the
glucosidic form and are hydlolysed by the enzyme elaterase.
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19. Cycloartanes:
The ring closure of squalene 2,3-oxide yields
cycloartenol as an intermediate in plant sterol
biosynthesis. However, these phytosterols are also
found in the free state in a wide range of plants.
Medicinal examples include the neem and olive
plants, Euphorbio spp., Hypericum, the woody
nightshade and a number of members of the
Cucurbitaceae
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20. Steroid hormones:
A steroid hormone is a steroid that acts as a hormone
1. Sex hormones:
 Produced primarily in the gonads
 Mediate the growth, development, maintenance, and function of the
reproductive tract and the accessory sex organs
 These hormones fall into three chemically and physiologically distinct
categories;
Estrogens and Progestins. These regulate the various functions of
female reproductive tract.
Androgens. Stimulate the development of male reproductive organs
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21. 2. Adrenocortical hormones:
Produced by outer cortical portion of the adrenal glands
Divided into two classes, depending on their biological activity;
Mineralocorticoids.
Principally affect the excretion of fluid and electrolytes, with a
subsequent sodium retention
Glucocorticoids.
They regulate the metabolism of proteins and carbohydrates.
At the present time, the principal source of steroid chemical nucleus
used in drug industry is the plant kingdom.
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22. Glucocorticoids, Affect intermediary metabolism
Estrogens: Estradiol, Estriol, Estrone
Progesterone: Progesterone
Androgens: Testosterone, Dihydrotestosterone
(DHT), Androstenedione
Mineralocorticoids: Aldosterone,
Deoxycorticosterone
Glucocorticoids: Cortisone, Hydrocortisone
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23. 23

24. Commercial production of
steroids
 The steroid hormones and their semisynthetic analogues
represent a multi-million-dollar annual business for the
American drug industry
 In the past, the source of steroid hormones was from the
gonads and adrenal glands of animals
 The amount of hormones present in these glands was
extremely small; consequently, it was not practical to use the
pure hormone in the therapy
 At the present time, the principal source of the steroid chemical
nucleus used in the drug industry is the plant kingdom
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25.  These nucleuses are modified by chemical or
biological methods to produce steroid hormones
For example;
 Diosgenin (a sapogenins) Isolated from various
species of Dioscorea → Progesterone
 Stigmasterol Isolated from Glycine max (Fam.
Leguminosae) → Hydrocortisone
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26. Plant steroids used for the
synthesis of steroid
Hormones
Diosgenin: It is a steroidal sapogenin used to prepare
progesterone.
Stigmasterol:
It is converted chemically to progesterone which is then
chemically converted to cortisone. Cortisone is
dehydrogenated to form prednisolone.
Desoxycorticosterone that is a mineralocorticoid is
synthesized from stigmasterol.
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27. Cholesterol:
Cholesterol is used to prepare testosterone which is
the true testis hormone. It is used to treat various
reproductive dysfunctions in both males and
females.
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28. Bile Acids :
Bile acids are steroid acids, found predominantly in the bile of
mammals and other vertebrates
The primary bile acids formed in the liver of man are;
A. Cholic acid
B. Chenodeoxycholic acid
Generally, the bile acids do not exist in the free state, but are
conjugated through a peptide bond to either glycine or taurine
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29. Biosynthesis:
 The precursor of the bile acids is cholesterol, which is either
present in the diet or synthesized in the liver cells during the
course of fat metabolism
 The cholesterol is first converted to cholic acid and
chenodeoxycholic acid in about equal quantities
 These acids in turn combine principally with glycine and to a
lesser extent with taurine to form glyco- and tauroconjugated
bile acids
 Bile salts are the sodium salts of the conjugated acids
 These salts are then secreted in the bile; therefore, they are
referred to as bile acids/bile salts
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30.  About 94 % of the bile salts are reabsorbed into the blood from
the small intestine (enterohepatic circulation)
 The liver cells synthesize about 6 grams of bile salts daily
 Deoxycholic acid and lithocholic acid are also found in
substantial amounts in mammalian bile
 They are not formed in the liver
 They are produced in the intestinal tract by the action of
microorganisms on; Cholic acid to form deoxycholic acid
 Chenodeoxycholic acid to form lithocholic acid
 Their presence in the bile is attributed to enterohepatic
circulation
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31. Functions of bile salts
The bile and bile salts play three important roles in our body
1. Emulsifying or Detergent action
 Bile salts have a detergent action on the fat particles in the food
 This decreases the surface tension of the particles and allows agitation
in the intestinal tract to break the fat globules into minute sizes
2. Excretion of waste products
 Bile serves as a means for excretion of several important waste
products from the blood
 These include especially bilirubin and excesses of cholesterol
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32. 3.Micelles formation (help in
the absorption)
 Bile salts help in the absorption of fatty acids, monoglycerides, cholesterol,
and other lipids from the intestinal tract
 They do this by forming very small physical complexes with these lipids;
the complexes are called micelles
 These micelles are semi-soluble in the chyme because of the electrical
charges of the bile salts
 The intestinal lipids are “ferried” in this form to the intestinal mucosa,
where they are then absorbed into the blood
 Without the presence of bile salts in the intestinal tract, up to 40 % of the
ingested fats are lost into the feces, and the person often develops a
metabolic deficit because of this nutrient loss
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33. Ox bile extract
 Fresh ox bile is partially evaporated
 Mucous and albuminous matter is precipitated with alcohol, Filtered,
washed and evaporated to dryness at a temperature not exceeding 80
°C
 It contains an amount of the sodium salts of glycocholic acid and
taurocholic acid equivalent to not less than 45% of cholic acid
 It is used therapeutically as a choleretic (increase the volume of
secretion of bile from the liver)
 The use of chenodeoxycholic acid to dissolve gallstones is a significant
advance in drug therapy, But it is still in investigational stages
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34. Therapeutic uses of Steroids:
1.Treatment of Heart Diseases:
i. Improved Circulation:
They increase the force of systolic contraction. Increased cardiac
output causes decreased heart rate. The improved circulation tends to
improve renal secretion which relieves the edema often associated with
heart failure.
ii. Congestive heart failure:
Digitalis preparations, Lanatoside C, Gitalin and Digoxin are used for
the treatment of congestive heart failure.
Digoxin has a greater margin of safety than other drugs. Oubain is the
most rapidly acting cardiac glycoside for the treatment of cardiac
failure.
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35. iii.Cardiotonic:
Digitoxin is a cardiotonic that increases the tone of cardiac
muscles and thus causes the heart to empty more effectively.
Deslanoside is also a cardiotonic and is used to attain rapid
initial dosing by parenteral administration. Strophanthus also
acts as cardiotonic.
iv.Cardiac Tachyarrhythmia:
Digoxin is used for the treatment of Cardiac arrhythmias.
v.Cardiac depression:
veratrum viride (green hellebore) acts as cardiac depressant
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36. vi.Hypercholestrolemia:
Plant sterols lower the LDL cholesterol levels in hypercholestrolemic,
diabetic and healthy human volunteers. They lower LDL levels without
affecting HDL level. They exert hypercholestrolemic effects possibly by
interfering with uptake of both dietry and biliary cholesterol from
intestinal tract.
They are now used as first line therapy as well as adjunctive therapy in
patients on statin therapy.
vii.Emetics:
Red squill contains cardiac glycosides induces the vomiting reflex and
reduces the life threatening aspects of toxic menifestations.
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37. viii.Expectorants:
Squill also acts as expectorant.
ix. Sedative and Hypnotics:
Withanolides act as sedatives and hypnotics.
x.Antitumors:
Some withanolides are cell differentiation inducers
whereas others act as antimitotics. Cucurbitacins
have cytotoxic and antitumor properties.
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38. xi.Hypotensives:
veratrum viride contains alkaloids that are responsible
for their hypotensive activity.
xii.Insecticides:
veratrum spp and cevadilla seeds act as insecticides.
xiii.Antiseptics:
Withanolides act as antiseptics.
xiv.Antiamoebics:
Kurchi or Hollarhena bark is used for amoebic dysentery.
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39. xv.Rheumatide Arthritis:
Natural cortisones are used to treat rheumatide
arthritis. Glucocorticoids are also used for the
treatment of rheumatism.
xvi.Electrolyte balance:
Deoxycorticosterone synthesized from stigmasterol
is used to restore a balance of sodium and
potassium in body fluids and restore kidney
function in cortical deficiency.
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40. Other therapeutic applications
of plant sterols:
They are also used for:
 Treating gall stones.
 Boosting immune system.
 Treating common cold and flu.
 Treating asthma.
 Relieving menopausal symptoms.
 Helping with hair loss or baldness.
 Relieving enlarged prostate symptoms.
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