Steroids

STEROIDS
Ameera Ehsan
G1F17BSCH0002
Iqra Saleem G1F17BSCH0006
Usmana Zia G1F17BSCH0009
Farheen Fatima

Contents
Sample Footer Text 2/8/20XX 2
Introduction
Classification
Cholesterol
Testosterone
Progesterone
Aldosterone
Importance
Conclusion

Introduction:
Lipids are substances soluble in organic
solvents and insoluble in water. The extraction
of plant and animal tissues with organic
solvents such as ether, chloroform Or benzene
yields Lipids. Lipids so obtained are of two
main categories;
• The 1st are converted into water soluble matter on
sponification (Alkaline hydrolysis)
• The 2nd are do not get converted Into water soluble matter
on sponification Like STEROIDS. Steroids (Greek stereos
= solid) are compounds possessing a characteristic
tetracyclic carbon skeleton, the perhydrocyclopentano
phenanthrene nucleus.

Structure:
A steroid is an organic compound with Four
fused rings arranged in a specific
molecular configuration.
The steroid core structure is composed of
seventeen carbon atoms(17), bonded in
four rings.
Three six-member cyclohexane rings (rings
A , B and C in the first illustration) and one
five-member cyclopentane ring (the D ring).
Steroids vary by the functional groups
attached to this four- ring core and by the
oxidation state of the rings.

History:
Most sources suggest
that scientists began to
experiment with synthetic
testosterone in the late
1880s.
The first steroid was
synthesized in 1938.
The Health Organization
of the League of Nations
immediately recognized
Anabolic steroids as
performance-enhancing
drugs.
However, health
companies did not begin
to regulate steroids until
the late 1990s.

Classification:
Sterol:
• Also known as steroid alcohols.
• where R is an aliphatic side chain.They contain usually
one or more hydroxyl groups(-OH) attached in alicyclic
linkage.
• Occur naturally in plants, animals, and fungi, with the
most familiar type of animal sterol being cholesterol.

Types:
• Phytosterols – plant sterol (Campesterol, Sitosterol,
and Stigmasterol).
(Blocks cholesterol absorption sites in the human
intestine, thus helping to reduce cholesterol in humans)
• Zoosterol – animal sterol (Cholesterol).
• Ergosterol – sterol present in the cell membrane of
fungi.

Bile acids:
• Are steroid acids found predominantly in the bile of mammals and other
vertebrates.
• where R is essentially a five-carbon side chain ending with a carboxylic acid
moiety
• Are conjugated with taurine or glycine in the liver, forming bile salts.
Primary bile acids are those synthesized by the liver. Secondary bile acids
result from bacterial actions in the colon.
• Functions:
• To remove unwanted cholesterol from the body.
• To aid in lipid digestion in the intestine.

Cardiac glycosides:
• Are glycosides of mostly C23-steroidal compounds.
• where R is a lactone ring.
• Are called cardiac glycosides because they modify
heart action.
Medicinal importance:
• They are cardiotonics used to treat Congestive heart
failure (CHF).
• They increase force of contraction of cardiac
muscles without increase oxygen consumption.

Steroid
hormones:
• where R bears a ketonic (C=O) or hydroxyl group(-OH) and
mostly possess a two carbon side chain
• A steroid that acts as a hormone
• Can be grouped into five groups by the receptors to which they
bind: glucocorticoids, mineralocorticoids, androgens,
estrogens, and progestogens.
• Steroid hormones help control Metabolism, inflammation,
immune functions, salt and water balance, development of
sexual characteristics, and the ability to withstand illness and
injury.

Sapogenins:
• Sapogenins :- where R
contains an oxacyclic
(etheral) ring system.
• Sapogenin, any of a class
of organic compounds
occurring in many species
of plants as derivatives of
the Steroids.
• Sapogenins
contain steroids or
other triterpene framewor
ks as their key organic
feature.

Mechanism of action:
• Simple Diffusion: The lipid soluble hormones diffuses through the cell membrane to enter the cell.
• Hormone binds to the intracellular receptor composed of a "Hormone binding" domain, a "DNA binding"
domain and a "amino terminal" which interacts with other transcription factors. Binding of the hormone leads
to exposure of DNA binding zone.
• Hormone-receptor complex enters nucleus and dimerizes.
• Binding to HREs: Hormone-recpetor dimers bind to Hormone (Steroid) Receptor Elements (SREs or HREs)
of DNA.
• Transcription: DNA transcription leads to formation of mRNA.
• Translation: mRNA undergoes translation to produce new proteins. e.g. Calbindin for Vitamin D
• Physiologic action of hormones.

Tests of
steroids:
(a) Liebermann-Burchard’s test:
2 mg of dry extract was dissolved in acetic anhydride,
heated to boiling, cooled and then 1 ml of concentrated
sulphuric acid was added along the sides of the test tube.
Formation of green colour indicates the presence of
steroids.
(b) Salkowski reaction:
2 mg of dry extract was shaken with chloroform, to the
chloroform layer sulphuric acid was added slowly by the
sides of test tube.
Formation of red colour indicated the presence of
steroids.

STEROL
Sterol is a class of steroids
containing OH group at C-3
position and a side chain of
8 to 10 carbon atoms.
Sterol is a chemical
compound with
formula C17H28O.

CHOLESTEROL
• Cholesterol is the major sterol in the animal tissues.
• Cholesterol is present in tissues and in plasma
either as free cholesterol or as a storage form,
combined with a long-chain fatty acid as cholesteryl
ester.
• In plasma, both forms are transported in
lipoproteins.

CHOLESTEROL
• The structure of
cholesterol consists of
four fused rings (The
rings in steroids are
denoted by the letters
A, B, C, and D.), with
the carbons numbered
in the sequence, and
an eight numbered, and
branched hydrocarbon
chain attached to the D
ring.

SALIENT FEATURES OF CHOLSTEROL
BIOSYNTHESIS
Substrate : Acetyl CoA
Site: Liver, intestine, skin, adrenal cortex, gonads, neural
tissues, placenta
Nature: Anabolic
Compartment: Cytoplasm
Rate limiting enzyme: HMG CoA reductase

BIOSYNTHESIS OF
CHOLSTEROL
• Biosynthesis of cholesterol generally takes place in the
endoplasmic reticulum of hepatic cells and begins with acetyl-
CoA, which is mainly derived from an oxidation reaction in the
mitochondria. However, acetyl-CoA can also be derived from
the cytoplasmic oxidation of ethanol by acetyl-CoA synthetase.
Acetyl-CoA and acetoacetyl-CoA are converted to 3-hydroxy-
3-methylglutaryl-CoA (HMG-CoA) by HMG-CoA synthase.
• HMG-CoA is then converted to mevalonate by HMG-CoA
reductase (HMGR). This reaction is completed with the aid of
NADPH, which is used as a cofactor for all reduction reactions
throughout cholesterol synthesis. Mevalonate undergoes a
series of phosphorylations and a decarboxylation yielding the
isoprenoid, isopentenyl pyrophosphate (IPP). A series of
condensing reactions occur, catalyzed by squalene synthase,
leading to the production of squalene. From squalene,
lanosterol, the first of the sterols is formed. The conversion of
lanosterol to cholesterol requires 19 additional reaction steps.

FUNCTION OF CHOLESTEROL
Cholesterol is the most abundant sterol in humans and
performs a number of essential functions.
It is a major constituent of the plasma membrane and of plasma
lipoproteins.
It is a precursor of bile salts/bile acid.
It is a precursor of steroid hormones that include adrenocortical
hormones, sex hormones, placental hormones etc

Testosterone
 Testosterone is the hormone responsible for
the development of male sexual
characteristics.
 Hormones are chemical messengers that
trigger necessary changes in the body.
 Females also produce testosterone, usually
in smaller amounts.
 It is a type of androgen produced primarily by
the testicles in cells called the Leydig cells.

Role of Testosterone:
Mind
Helps to
maintain a
feeling of
wellbeing.
Sexual
function
Maintain
sexdrive and
fertility.
Body
Helps to
maintain
healthy bones
and muscle

Role in body:
 In men, testosterone is thought to regulate a number of functions alongside sperm production.
These include:
 sex drive
 bone mass
 fat distribution
 muscle size and strength
 red blood cell production
 Without adequate amounts of testosterone, men become infertile. This is because testosterone
assists the development of mature sperm.
 Despite being a male sex hormone, testosterone also contributes to sex drive, bone density, and
muscle strength in women. However, an excess of testosterone can also cause women to
experience male pattern baldness and infertility.

Biosynthesis of testosterone:

Synthesis of testosterone:
A- F R O M C H O L E S T E R O L
B - F R O M
D I H Y D R O E P I AN D R O S T R E O N E

Synthesis:
• Cholesterol acetate dibromide is first prepared by the acylation of cholesterol and its
subsequent bromination, this is oxidation with chromium-6-oxide which on reduction
yields dehydroepiandrosterone.
• The resulting product on acylation and with the treatment with sodium peroxide
introduces a hydroxyl group.
• Benzoylation followed by mild hydrolysis causes the reappearance of free OH
constituent.
• Oppeanauer oxidation caused by refluxing the resulting secondary alcohol with
aluminium tertiary butoxide in excess of acetone affords a ketonic function at C-3
which on hydrolysis yields the official compound.

Metabolism of action:
Testosterone binds to a specific receptor in a
target cell.
Telesteron itself is the active ligand in muscle
and liver but in other organs it must be
metabolized to dihydroxytestosterone (DHT)
to show its action.

Fun facts:
 A mother testosterone level during pregnancy is correlated with her
daughter’s sex-typical behavior as an adult, the correlation is even
stronger than the daughter’s own adult testosterone level.
 Falling in love decreases men’s testosterone level while increasing
women’s testosterone level.
 Fatherhood decreases testosterone levels in men.
 Testosterone levels plays a major role in risk-taking during financial
decisions.
 Testosterone in the presence of a slow-growing cancer is assumed to
increase its growth.

Testosterone decreases with age
In males as well as females

Estrogens are hormones
that are important for
sexual and reproductive
development, mainly in
women.
They are also referred to
as female sex hormones.
Estrogen

• Estradoil
• Estroil
• Estrone
Natural Estrogen
• Steroidal: Ethinylestradiol, mestranol
• Non-Steroidal: Diethylstilbestrol, hexestrol, dienestrol
Synthetic Esrogen:
Classification

Natural
Estrogen • Secreted by ovary
• Synthesized in graafian
follicle, corpous luteum
and plaxenta from
cholesterol

Function of
estrogen
• Ovaries: Estrogen helps stimulate the growth of
the egg follicle.
• Vagina: In the vagina, estrogen maintains the
thickness of the vaginal wall and promotes
lubrication.

Conti..
• Uterus: Estrogen enhances and maintains the
mucous membrane that lines the uterus. It also
regulates the flow and thickness of uterine mucus
secretions.
• Breasts: The body uses estrogen in the formation of
breast tissue.

Progesterone
• Progesterone belongs to a group of steroid
hormones called progestogens.
• Progesterone is a hormone released by the
corpus luteum in the ovary. It plays important roles
in the menstrual cycle and in maintaining the early
stages of pregnancy. It may also be involved in the
growth of certain cancers.

Synthesis of Steroids
2/8/20XX 42
• From Diosgenin • From Cholesterol

Uses
• Prevention of abortion
• Function in bone strength, skin elasticity,
nerve tissue.
• Receptors in certain muscle and fat
tissues.
• Treatment of breast carcinoma
• Treatment of dysmenorrhea
• Treatment of catamenial epilepsy
• Oral contraceptives

Adrenocorticosteroid
s
Adrenocorticosteroids are group of hormones
that are produced in the adrenal cortex of
humans.
They are involved in many types of functions
including:
• Stress response
• Immune response
• Regulation of inflammation
• Carbohydrate metabolism
• Protein Catabolism
• Blood electrolyte levels
• Behavior
2/8/20XX
Sample Footer Text 44

Glucocorticoids
• Glucocorticoids are steroid
hormones synthesized and
secreted by the adrenal gland
in response to stress.
• Both natural and synthetic
glucocorticoids are widely
prescribed as anti-
inflammatory drugs

Glucocorticoids
•Cortisol.
•Cortisone.
•Corticoid.
•Dexamethasone.
•Corticosterone.
•Prednisone.
2/8/20XX

Cortisol/ Hydrocortisone
• Cortisol plays an important role in a number of
things your body does. For example, it:
• Manages how your body uses carbohydrates,
fats, and proteins
• Keeps inflammation down
• Regulates your blood pressure
• Increases your blood sugar (glucose)
• Controls your sleep/wake cycle
• Boosts energy so you can handle stress and
restores balance afterward

Prednisolone
Prednisone is a corticosteroid
that is used to reduce
inflammation and calm down an
overactive immune system. Its
glucocorticoid activity is greater
than its mineralocorticoid activity,
which means that it has more
effects on the immune response
and inflammation than it does on
electrolytes and fluid.
2/8/20XX

Mineralocorticoids
• Mineralocorticoids are a class of corticosteroids, which
in turn are a class of steroid hormones.
• Mineralocorticoids are produced in the adrenal
cortex and influence salt and water balances
(electrolyte balance and fluid balance).
• The primary mineralocorticoid is aldosterone.

Aldosterone
• Aldosterone, a steroid
hormone secreted by
the adrenal glands.
Aldosterone serves as
the principal regulator
of the salt and water
balance of the body
and thus is categorized
as a mineralocorticoid.
It also has a small
effect on the
metabolism
of fats, carbohydrates,
and proteins.

Cholesterol
• Cholesterol is the most common steroid and is the
precursor to vitamin D, testosterone, estrogen, progesterone,
aldosterone, cortisol, and bile salts.
• Cholesterol is a component of the phospholipid bilayer and
plays a role in the structure and function of membranes.

Steroids & Brain
• Steroids are found in the brain and alter electrical activity in the
brain.
• Because they can tone down receptors that communicate messages
from neurotransmitters, steroids are often used in anesthetic
medicines.

Cholesterol & Atherosclerosis
In the disease atherosclerosis, fatty materials
containing cholesterol form deposits (plaques),
especially in the walls of the major blood vessels, and
vascular function may be fatally impaired. The
disease has many contributory factors but typically is
associated with elevated concentrations of
cholesterol in the blood plasma. One aim of medical
treatment is to lower the plasma cholesterol level.
2/8/20XX

Cardiotonic
steroids
• Preparations in which cardiotonic
steroids of both vegetable
and animal origin are the active
principles have been used as
emetics, diuretics, and arrow poisons
for centuries.
• The use of digitalis, ouabain, and
strophanthin glycosides to slow the
rate and strengthen the contractility of
the failing heart is one of the most
important methods of treatment of
this condition.
• Of these agents, the digitalis
glycosides are the most widely used.
The therapeutic effects of these
agents are related to their influence
on muscle cells of the heart.

Steroid contraceptives
• The most effective method of contraception uses
combinations of synthetic estrogen and progesterone that
prevent ovulation.
• Unlike the natural hormones, these synthetic steroids are
highly active when taken orally as tablets.
• Estrogens that have been used in oral contraceptives include
estranol which has about the same potency as estradiol, and
mestranol, which is less potent.
• Contraceptive steroid preparations are also used for control of
breeding cycles and synchronization of estrus in farm animals.

Androgens and anabolic steroids
• A growing number of amateur and professional
athletes have made use of synthetic analogs
of testosterone to accelerate muscular
development and to improve strength.
• Medical researchers have determined that the
use of anabolic steroids may lead to heart disease,
sexual and reproductive disorders, immune
deficiencies, liver damage, stunted growth (in
teenagers and young adults), and aggressive,
violent behaviour.

Vitamin D2 & D3
• In
mammalian skin one precursor of cholesterol, 7-
dehydrocholesterol, is converted by
solar ultraviolet light to cholecalciferol, vitamin D3,
which controls calcification of bone by regulating
intestinal absorption of calcium. The
disease rickets, which results from lack of
exposure to sunlight or lack of intake of vitamin D,
can be treated by administration of the vitamin or
of the corresponding derivative of ergosterol,
ergocalciferol (vitamin D2).

Adrenal Steroids
• Failure of the adrenal cortex in humans gives rise
to Addison disease, a formerly fatal condition that
can now be successfully treated
with synthetic adrenal steroids.

Glucocorticoids
• The glucocorticoids promote
the deposition of glycogen in the
liver and the breakdown of
body proteins.
• The secretion of
glucocorticoids is exquisitely
responsive to injury and fear in
animals and is primarily
responsible for
metabolic adaptation to stressful
conditions.

Cardenolide:
Nature’s
weapon
• Cardenolide and bufanolide
derivatives, found in many plants and
in the skin of toads, cause vomiting,
visual disturbances, and slowing of
the heart in vertebrates and are
strong deterrents to predators. Birds
and other predators instinctively
avoid
certain grasshoppers and butterflies t
hat store cardenolides of the plants
upon which they feed.

Summary
• Steroid, any of a class of natural or synthetic organic
compounds characterized by a molecular structure of 17 carbon atoms
arranged in four rings.
• Steroids are important in biology, chemistry, and medicine.
• The steroid group includes all the sex hormones, adrenal cortical
hormones, bile acids, and sterols of vertebrates, as well as
the molting hormones of insects and many other physiologically active
substances of animals and plants.
• Among the synthetic steroids of therapeutic value are a large number of
anti-inflammatory agents, anabolic (growth-stimulating) agents, and oral
contraceptives.
• Steroids vary from one another in attached groups, the position of the
groups, and the configuration of the steroid nucleus (or gonane).
• Small modifications in the molecular structures of steroids can produce
remarkable differences in their biological activities.

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