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1.0 INTRODUCTIONS
1.1 General structural properties of steroids
Steroid is a compound that contains the ring system which contains four rings that
are named 1,2-cyclopentano-perhydrophenantrene and each ring is designated to A, B, C
and D accordingly. The numbering of the carbons should start with ring A, B, C and D.
The carbon are numbered as shown in the diagram below, starting from ring A and
subsequently progressing the numbering to ring D, then to the angular (bridgehead)
methyl groups usually on position carbon 10 and 13 and finally to side chain linked to the
carbon 17.
The naming of the particular steroids can be differ by varying the steroid nucleus
with different side chains. Most of the steroids may be named based on the derivatives of
this structure, which is called cholestane shown in the above figure. It is to say that all
steroids share similar chemistry & nomenclature due to its structural similarities as
steroid ring with common numbering system present. Therefore, if there is small changes
in structure can dramatically affect the conformation and configuration of the molecule.
The presence of different location of different substituents in the ring system will
then influence the pharmacological & physiological activity of the steroid.
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1.2 Stereochemistry of steroids
The interesting feature of the steroid stereochemistry is that the six-membered
rings can present in fixed chair conformations. The two cyclohexane rings can be joined
in either a cis or a trans conformation. In cis-decalin, both groups at the ring-junction
positions are on the same side of the two rings. However, in trans-decalin, the groups at
the ring junctions are on opposite sides. Theoretically the trans isomer is more stable in
the structure. The four fused-ring structure can have three dimensional structures in its
configurational isomers as the following figure:
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2.0 CLASSIFICATION OF STEROIDS
2.1 Animal steroids
2.1.1 Insect steroids
Metamorphosis hormones: Ecdysteroids such as ecdysterone.
2.1.2 Animal steroids
Sterol (cholesterol, stigmasterol and vitamin D3)
Bile acid and bile salt
Steroid hormones
Sex hormones
i. Female sex hormones
- Estrogen
- Progestins(progesterone)
ii. Male sex hormones (androgen)
- Testosterone,
- Anabolic steroids
Adrenal cortex hormones (corticosteroids)
- Glucocorticoids (cortisol or hydrocortisone and cortisone)
- Mineralocorticoids (aldosterone)
2.2 Plants steroids
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Phytosterols
Brassinosteroids
2.3 Fungus steroids Ergosterols
2.4 Synthetic drugs of steroids
Cardiac glycosides (digitalis)
Prednisolone
3.0 STRUCTURAL CHEMISTRY OF DIFFERENT TYPES OF STEROIDS
3.1 Sterol
Sterol is one of group of steroid alcohol with multi-ring structure and it is the
derivatives of steroids with hydroxyl group attached to the carbon 3 of the ring A. This
hydrocarbon side chain can poses the polarity in the structure. The alipathic chain
including the four ring system shows hydrophobicity or non-polar properties. Thus it is
considered as the amphipathic lipids since the structure can have both hydrophilic and
hydrophobic characteristics. It can be esterified into thelipid bilayers of the cell
membrane. However, sterols onlyexist in the membranes ofeukaryotes, none of the
plants have sterols in membranes except mycoplasmas. The following diagram indicates
the association of the sterol molecules with the amphipathic cytoplasmic membrane.
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We can say that the overall structure results in the water insolubility of the
compound as there is only one ionizable residue present in the structure. Sterols and their
fatty-acid estersare essentially waterinsoluble. Sterols sometime contain one or more
double bonds in the ring structure and there are also a variety of substituents attached to
the rings. In eukaryoticorganisms, sterol is most represented by cholesterol and
ergosterol (yeast). Besides, stigmasterol is the most common phytosterol in plants.
3.2 Cholesterol
Cholesterol has a molecular formula of C27H45OH and it is composed of a
hydrocarbon tail ring structure with 4 hydrocarbon rings as well as a hydroxyl group
attached to the carbon 3. The hydroxyl group is polar, which makes it soluble in water
and it can exert some alcoholic characteristics. The 4-ring region of cholesterol is the
significant of all steroids. Each corner of the ring is composed of a carbon atom, with
extending two hydrogen atoms. Cholesterol is regarded as "sterol" in response to the
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combination of the steroid ring structure and the hydroxyl group. Basically, cholesterol is
the animal sterol since there are small amounts of cholesterol made in plants. The
hydrocarbon tail is composed of carbon and hydrogen atoms like the steroid. Both the
ring region and tail region are non-polar, this is the reason why they are capable of
dissolving in fatty and oily substances but is not soluble with water. This make the
structure become amphipathic as both a water-soluble region and a fat-soluble region
present in the structure.
3.3 Vitamin D
Vitamin D which is called as calciferol and it is a fat-soluble vitamin since it can
be synthesized from cholesterol. The figure above shows the structures of vitamin D2
(ergocalciferol) and vitamin D3 (cholecalciferol).
3.4 Bile acid and bile salts
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Bile secretion is carried out in the liver and stored in the gall bladder. It is made
up of the bile acids or bile salts which contains cholic acid and chenodeoxycholic acid.
Both compounds show rigid steroid nucleus and a short aliphatic side chain. Thisinvolves 3 six-member rings (A, B and C) and a five member ring (D). The angular
methyl groups are present at positions C-18 and C-19. The classification of the structure
is based on the side chain of the compound. Cholic acid has an extra hydroxyl residue
attached at position C-12 in ring C comparing to chenodeoxycholic acid due to the
different synthesis pathway from cholesterol. Bile acids are amphipathic which contain
both hydrophobic (lipid soluble) and hydrophilic (polar) properties.
3.5 Female Sex Hormone
3.5.1. Estrogen
Estrogen is derived from terpenes and it carries with 4 condensed rings like others
steroid derivatives. A rings has a hydroxyl group and oxygen substituent present while the
D ring is extending with an alkyl chain. The classic estrogens are estrone, 17-
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estradiol (most potent), and estriol. Estrogen shows the absence of methyl group in C19
and surprisingly ring A indicates aromatic characteristics.
3.5.2. Progestins
Progesterone is the model molecule of sex hormones. It consists of four
interconnected cyclic hydrocarbons. There are ketone and oxygenated functional groups
with two methyl branches exit in the structure. It is hydrophobic in nature.
3.6 Male Sex Hormone
3.6.1. Testosterone
Testosterone naturally produced in the human body has the chemical formula C19H28O2.
Testosterone is referred as a "bioidentical hormone" which represents the similar
chemical structure to natural synthesized hormone. However, chemical modification in
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the testosterone molecule by adding a side chain or functional group will produce
"synthetic" hormone such as methyltestosterone and some anabolic steroids.
Androgenic steroid can give effects in the male secondary sexual characterization and
male reproductive tract development.
3.7 Adrenal cortex hormones
Theoretically, these compounds should be formed in the adrenal cortex.
Furthermore, they must be C-21 steroids and three or more oxygen atoms. They have all a
en-4-one-3 group and an oxygenated function at C-20.
3.7.1. Glucocorticoids
Cortisol has a general formula of C21H30O5 and it has a hydroxyl group at C-11, C-
17, and C-21. It is produced by the adrenal cortex which regulates carbohydrate
metabolism and controls blood pressure. Cortisol can be used to treat inflammatory
conditions and adrenal failure. It may convert to hydrocortisol or cortisone when
undergoing the metabolism.
3.7.2. Mineralocorticoids
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Aldosterone has one hydroxyl group at C-11 and one aldehyde function at C-18.
4.0 BIOLOGICAL ACTIVITY AND PHYSIOLOGICAL FUNCTIONS OF
STEROIDS
4.1 Cholesterol
Sterols are widely distributed and embedded in cell membrane as if in the figure
above. Modifications of the steroid ring structure are made by specific enzyme systems,
producing the sterol characteristic for each species, such asergosterol in yeast. The
major regulatory step in the sterol biosyntheticpathway occurs early in the process.
Drugs that lower blood cholesterol levels in humans are designed to inhibit this
regulatory enzyme. In addition to their conversion to sterols, several intermediates in the
pathway are precursors of other important biological compounds, including chlorophyll
in plants, vitamins A, D, E, and K, and regulators of membrane functions and metabolic
pathways.
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For example cholesterol forms part of the cellular membrane where its presence
affects the cell membrane's fluidity and serves as secondary messengerin
developmental signaling. Cholesterol also serves as a precursor of steroidhormones
(estrogens, androgens, glucocorticoids, and mineralocorticoids) and bile acids.
Cholesterol can serve as precursor of all type of steroids.
4.1.1. Maintains the integrity of the cell membranes
Cholesterol is an amphipathic molecule which contains a hydrophilic (hydroxyl,
OH groups) and a hydrophobic (hydrocarbon tail) portion. The hydrophilic portion of
cholesterol aligns with the phosphate heads of the phospholipids while the remaining
portion of it tucks into the fatty acid portion of the membrane. Due to the way how
cholesterol is shaped, part of the steroid ring, the four hydrocarbon rings in between the
hydroxyl group and the hydrocarbon "tail", is closely attracted to part of the fatty acid
chain on the nearest phospholipid. This helps immobilize the outer surface of the
membrane slightly and make it less soluble to very small water-soluble molecules that
could otherwise pass through the membrane more easily.
4.1.2. Helps maintain the fluidity of the cell membranes
It helps in preventing the fatty acid chains in the cell membrane from packing
together and crystallizing by separating the phospholipids when there is high
concentration of cells in the body fluids and thus provides a consistency to the cell
membranes.
4.1.3. Helps secure important proteins in the cell membrane
The lipid rafts in membranes contain cholesterol with longer and more saturated
fatty acid tails. Due to the shape of the cholesterols, they aggregate more in the
membrane which leads to the increase of the thickness of the membrane making it ideal
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for accommodating certain proteins that require special condition to function properly
like sticking with other proteins to carry out their functions.
4.1.4. Arteriosclerosis and cholesterol
Cholesterol is the most widespread animal steroid and found in almost all animal
tissues. For example, egg yolks are rich resource of this compound. Cholesterol is an
important component of cell membranes and can serve as intermediate in the biosynthesis
of the steroid hormones. However, because it can be synthesized from acetyl coenzyme
A, it is usually not a dietary necessity. High levels of cholesterol in blood are associated
with atherosclerosis (hardening of the arteries). This condition involves the accumulation
of cholesterol and other lipids in the lumen of the arteries.
Figure: Plaque formation on the arteries.
Lipoproteins play important roles in the arteriosclerosis disease. It is the carrier
for cholesterol and can be classified into HDL(high-density lipoprotein) and LDL(low-
density lipoprotein). It's often said that HDL is the good cholesterol and LDL is the bad
cholesterol. The elevation of the LDL level will deposit the plaque formation on the
arteries wall. It results in familial hypercholesterolemia which associates with the LDL
defect. The narrowing of arteries will lead to the blockage of the blood flow and cause the
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blood pressure become higher. This abnormal blood flow will cause the arteriosclerosis to
occur.
4.2. Vitamin D
Figure: Biosynthesis activation of cholecalciferol and ergocalciferol by ultraviolet light.
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The general structure represents the rings A, B, C, and D with differing side chain
residues. Basically, vitamin D3 which is found in human is considered as a seco-steroid
which involved the ring opening during the synthesis process. The 7-dehydrocholesterol
found in the skin and converted to vitamin D when in contact with ultraviolet light. This
process involves the bond breakage that happens in the carbon-9 and 10 in ring B with
the presence of ultraviolet light. The conjugated double bond system in the molecule
permits the light absorption of UV light at certain wavelengths. This initiates the structure
transformations and consequently results in the production of vitamin D3. This can
normally occur in the epidermis or skin of most animals.
For instance, the exposure of the sunlight is a better way to nourish our body with
vitamin D rather than the dietary requirement for this kind of vitamin. Vitamin D can
enhance the calcium and phosphorus which can promote their absorption from the skin
and deposition in the bone. Poor diet or lack of sunlight can cause rickets and
osteomalacia due to the vitamin D deficiency.
4.2.1. Promotes immune function in the skin
During wound healing, the expression of the antimicrobial peptide cathelicidin,
which can be induced in keratinocytes in vitro by vitamin D3 increases. Besides, the
vitamin D3 also induces the expression of Toll-like receptor 2 (TLR2) and the Toll-like
receptor cofactor CD14 in wounds and vitro. The increase in TLR2 expression allows
keratinocytes to respond to microbial stimulation and also generates an amplification
loop, the TLR2 signalling leads to increased expression of 1 -hydroxylase (which is the
enzyme that catalysts the conversion of inactive vitamin D3 to active form), and therefore
more production of active vitamin D3, which induces the expression of cathelicidin and
enhances the expression of TLR2.
4.2.2. Increases the serum calcium concentrations
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When the concentration of calcium ions is very low in the body, the parathyroid
hormone is induced which in turn stimulates the activation of vitamin D3. The active
form vitamin D3 will stimulate the increase of calcium absorption in intestine, increasing
osteoclastic resorption, and increasing distal renal tubular reabsorption of calcium. If the
calcium ions concentration is too high in the body, the active form vitamin D3 will be
suppressed which lead to the decrease in absorption of calcium ions and increase in the
excretion of excess calcium ions
4.3. Bile acid and bile salts
The metabolism allows cholic and chenodeoxycholic acid to be conjugated with
glycine or taurine to give the product of bile salt, which is the conjugated form of bile
acids
The metabolism allows cholic and chenodeoxycholic acid to be conjugated with
glycine or taurine to give the product of bile salt, which is the conjugated form of bile
acids.
4.3.1 Facilitate digestion and absorption of lipid
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They are emulsifying agents that have amphipathic molecules with both water-
soluble (hydroxyl groups, OH) and water-insoluble or fat-soluble (methyl groups, CH3)
parts that make them able to mix fats with water. These groups allow bile acids and salts
to break up large globs of fat, connecting to the fat on one side, and connecting to the
water on the other, thus mixing the fats and water together by wrapping around the fats.
The emulsifying process has increased the surface area of fats and making it available for
the digestion enzymes, lipases that are water soluble and cannot access the inside of lipid
droplets.
4.3.2 Solubilize and transport lipids in an aqueous environment
Their amphipathic nature has enabled them to carry the lipids and solubilize lipids
by forming micelles with phosphatidylcholine which are aggregates of lipids such as fatty
acids, cholesterol and monoglycerides that remain suspended in water.
4.4. Female Sex Hormone
4.4.1. Estrogen
Estrogen refers as the primary female sex hormone. It is present in both men and
women, but level of estrogen is higher in female. They stimulate female secondary sex
characteristics development, particularly in breasts, thickening of the endometrium and
their roles in the menstrual cycle. Follicle stimulating hormone (FSH) and luteinizing
hormone (LH) are the key hormone that control the secretion of estrogen.
4.4.1. (i) Stimulate protein synthesis.
It stimulates protein synthesis by entering the target cells and binds to a specific
receptor molecule to form a complex. The complex is then altered in such a way that it
can enter the cell nucleus and bind to nuclear components to promote the transcription of
specific messenger RNA (mRNA) which is then translated into specific proteins.
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4.4.1. (ii) Promotes secondary growth of female sex characteristics
The development of secondary female sex characteristics are stimulated by the
estrogens via the promotion of the accumulation of fats at the breast, hips, buttocks and
so on.
4.4.1. (iii) Prevent the development of osteoporosis
Estrogen blocks the activation of the bone metabolic unit and its effects may be
mediated in part by growth factors and interleukins. The estrogen prevents the
development of osteoporosis by blocking the synthesis of interleukin 6 which is a potent
stimulator of bone resorptions by osteoblast.
4.4.2. Progestins
Progesterone has similar pharmacological actions as estrogen. The target sites of
this hormone basically will be in the uterus, breast and brain can be done. The
development of the secondary endometrium can be done by progesterone. It usually takes
part at the end of the menstrual cycle. Progesterone enhances the cervical secretion and
reducing cervical penetration by sperm. Progesterone can decrease the contraction of the
uterus and thus promote the maintenance of pregnancy. Besides, by the aids of estrogen,
it is capable of stimulating the breast lactation during pregnancy. It is to notice that
testosterone and estrogen can be made from progesterone as well.
4.4.2. (i) Increase relaxation and reduce anxiety
In the brain, the progesterone provide a soothing effect in such a way that is
similar to the effects of benzodiazepins by a direct effect on neurotransmitter receptors
called Gamma-Amino Butyric Acid type A (GABAA) receptors. The action of
progesterone on GABAA receptors has been associated with an increase in appetite and
food intake.
4.4.2. (ii) Provide metabolic and nutritional effects
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It opposes the effect of estrogen in the tendency of storing fat by promoting the
use of fat for energy. It also normalizes blood sugar levels by interfering with the action
of insulin and counters the binding of estrogen with zinc and copper.
4.4.2. (iii) Involve in treatment of thyroid dysfunction
It counteracts the inhibition of thyroid hormone actions by estrogen via keeping
zinc and potassium in cells. The keeping of zinc and potassium in cells is important to
allow the entrance of thyroid hormone that will be converted into its active form, T3 to
carry out its function in the cells.
4.5. Male Sex Hormone
4.5.1. Testosterone
Testosterone poses virilizing and anabolic effects Anabolic effects include growth
of muscle mass and strength, increased bone density and strength, and stimulation of
height growth and bone maturation. Virilizing effect associates with the sex organ
maturation especially in penis and scrotum formation in fetuses and at puberty and voice
deepening.
4.5.1. (i) Promote erection
Testosterone is the precursor of the formation of dihydrotestosterone (DHT)
which is the regulator of nitric oxide (NO) and cyclic guanosine monophosphate (cGMP).
Both of these compounds involve in the relaxation of smooth muscle that controls the
blood vessels within the penis. When the smooth muscles in the tissues of penis relax, the
tissues become engorged with bloods and this leads to the erection of penis.
4.5.1. (ii) Protect the brain against Alzheimers disease
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The brain is protected against Alzheimers disease through the inhibition of two
hallmarks of Alzheimers disease pathology, -amyloidfound in senile plaques and
hyperphosphorylated tau found inneurofibrillary tangles, by testosterone. The
testosterone reduces -amyloid secretion in cortical neurons by altering the processing of
the amyloid precursor protein.
4.5.2. Anabolic steroids
The term anabolic is derived from Greek word, it gives the meaning of build
up. Some references use the term anabolic-androgenic steroids (AAS) to represent
anabolic steroids. Nitrogen-retaining effects of androgen can boost the development of
the large muscle mass in males. This is because it has a protein building property which
leads to an increase in muscle strength. If comparing the testosterone and anabolic
steroid, both of them can play different roles of functional properties in our body.
Androgenic activity is essential for male sex drive and performance. It improves
secondary sexual characteristics development and play roles in spermatogenesis.
Anabolic activity enhances muscle mass development, strength, or endurance. It
sometimes functions in the reversion of catabolic process or tissue-depleting conditions.
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4.5.2. (i) Help patients gain weight after a severe illness, injury or continuing
infection
It helps to increase the bodys ability to use proteins to make muscle by sending
the amino acids which are the building blocks of proteins needed by muscle to grow back
to the muscles. It also prevents the breakdown of muscle and enhances recovery by
inhibiting the binding of cortisol (a stress hormone that is secreted during exercise to
enhance the use of proteins for fuel and to suppres inflammation that accompanies tissue
injury) to its receptor sites during and after exercise.
4.6. Adrenal cortex hormones
4.6.1. Glucocorticoids
Glucocorticoids can be secreted by the outer part of the adrenal gland. It is
released during stress conditions and has strong anti-inflammatory actions.
4.6.1. (i) Protects the brains
Under stress conditions, cortisol stimulates the breakdown of the structural and
functional proteins instead of the brain fats to release amino acids to provide the body
energy. These amino acids are then converted into useable carbohydrate (glucose) via the
process of gluconeogenesis in the liver. It also inhibits the transport of amino acids into
other types of cells and inhibits glucose uptake and oxidation by other cells.
4.6.1. (ii) Helps fight inflammation to minimize cellular damage
The cortisol controls the level of inflammation of injuries by influencing the
functions of lymphocytes, macrophages and leukoctyes with the utilization of energy to
direct their movement to specific locations. Beside that, it also inhibits the production of
some cytokines such as interleukin-1 and mediates several components of the
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inflammatory response. As a result, destruction of the cells caused by inflammatory
response can be minimized.
4.6.1. (iii) Decrease inflammation responses
Cortisone decreases inflammation (swelling) by preventing infection-fighting
white blood cells (leukocytes) from traveling to the area of swelling in the body. For
example, in the spine, brain or bone, it can decrease the pressure formed by the
inflammation responses on nerve endings and relieve pain.
4.6.2. Mineralocorticoids
Figure: Angiotensin and renin action on blood pressure regulation.
Aldosterone has important functions in regulating the electrolyte balance in body.
The location of action is mainly kidney and it functions to reduce the rate of sodium-ionexcretion with water retention. This will increase the rate of potassium-ion excretion.
The secretion of aldosterone appears to be regulated by two mechanisms. When the
concentration of dietary sodium ions is limited, rates of aldosterone secretion will be
increased. If there is reduced blood flow happens, it stimulates kidney cells to produce
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the renin, a proteolytic enzyme. It functions in converting the inactive angiotensinogen
globulin into angiotensin I(active). After angiotensin I convert into angiotensin II by
another enzyme, this promote the aldosterone secretion from the adrenal cortex. It results
in retention of salt and water in the blood. By this way, the blood pressure can be easily
regulated by the aldosterone with homeostasis effect. However, excessive sodium and
water retention will cause edema.
4.6.2. (i)Maintains sodium and water homeostasis
Aldosterone helps regulate the bodys electrolyte balance by stimulating
reabsorption of sodium and water along with the excretion of potassium. It increases the
transport of sodium through the activation and synthesis of epithelial sodium channels in
the kidneys, intestine, sweat and salivary glands. The subsequent increased
concentrations of sodium in the cells activate Na+/K+ ATPase molecules which transport
the sodium back into the bloodstream.
4.6.2 (ii) Regulates acid or base balance
When the level of acidity in the body fluid is too high, hydrogen (H+)ions are
secreted out from the intercalated cells in the collecting duct which is stimulated by
aldosterone together with the reabsorption of sodium and excretion of potassium, into the
urine to be excreted out from the body and thus preventing it form binding with
bicarbonate (HCO3) to form bicarbonic aicd (H2CO3). When the body fluid is too basic,
the bicarbonate ions will be reabsorbed in the kidney to bind with the hydrogen ions to
form bicarbonic acid to restore the acid or base balance of the body.
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5.0 APPLICATIONS AND USES OF STEROIDS
5.1 Gene therapy
Ecdysteroids are use in gene-switch systems as inducers. This means that
ecdysteroids are use for gene therapy. These systems are commonly used in vitro
with cultured cells, which analyse the role of a wide array of genes.
5.2 Treatment for diseases
5.2.1. Anti-inflammatory properties
5.2.1. (i) Ecdysteroids
Ecdysteroids use in wound healing, it had been approved that it can shorten
the duration of skin repair.
5.2.1. (ii) Prednisolone
It is used to treat arthritis, asthma, bronchitis, colitis, certain skin rashes and
allergic or inflammatory conditions of nose and eyes. It can be find in the form of
tablets, capsules, liquids, topical creams and gels, inhalers and eye drops,
injectable and intravenous solutions. Prednisolone is being used in the treatment of
blood cell cancers (leukemias), and lymph gland cancers (lymphomas). It is used as a
hormone replacement for whose adrenal glands are not function well. It is usually
used for joints pain and itchy skin. Prednisolone is used to reduce the level of calcium
in blood and it is used to treat patients who are after having trauma. Prednisone is a
synthetic prednisolone.
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5.2.2. Hormonal control
5.2.2. (i) Estrogen
Premarin is a synthetic estrogen to overcome menopause symptoms such as hot
flashes This estrogen drug is used to promote female gender-specific characteristics in
male-to-female transsexuals. Synthetic estrogen is used as birth-control drug, which
inhibit the production and secretion of gonadotropin-releasing hormone, luteinizing
hormone, and follicle-stimulating hormone.Besides, progestin is synthetic progesterone
to reduced menopause symptoms and promote female gender-specific characteristics.
5.2.2. (ii) Testosterone
Synthetic testosterone is used to treat infertility, testosterone deficiency in men and
symptoms of sexual dysfunction in men and women. It also can use as drugs for female-
to-male transsexuals. It also increase the bone mineral density of testosterone deficiency
patient to prevent bone fractures. It also used to prevent dementia and depression.
Testosterone is being used to treat women with premature ovarian failure, Turner's
syndrome, or HIV infection.
5.2.2. (iii) Others
Other steroids like glucocorticoids (Glaucotin) is use specifically to treat
Glaucoma. It has been used as clinical or non-prescription drugs for improvement in
hyperlipidemia.Sitosterols is one of the phytosterols that used to improve symptom of
benign prostatic hyperplasia. Cardiac glycosides (digitalis) is used to treat congested
heart failure and supraventricular tachysrhythmias (atrial flutter, atrail fibrillation and
paroxysmal supraventricular tachycardia,PSVT).
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5.3 Muscle development for athletes
Figure: The use of anabolic steroids on human.
Ecdysteroids was used to stimulate muscle growth, this led to physical performance
increased without training. For instance, sportsman can perform better than his usual
performances (perform out of his ability) after having this ecdysteroids. It also used as
non-toxic muscle-promoting substances for bodybuilders. Some athletes used synthetic
testosterone as a physical and performance enhancing drug illegally. It used to increase
body mass of organisms. Athletes used anabolic steroids to improve performance. It also
used to treat depression and increase a sense of well-being.
5.4 Hormone replacement therapy
Hormone replacement therapy (HRT) involves the participation of synthetic and natural
female hormones such as estrogen and progesterone. This is to overcome the lack of
natural hormones produced in female. The term estrogen replacement therapy (ERT) is
sometimes used. The administration of estrogen and progestin contribute to relieve the
menopause, osteoporosis, and reduce the risk of heart disease.
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6.0 PROS AND CONS OF STEROIDS
6.1 Advantages of steroids
6.1.1. Role of Steroids to Reduce Inflammation
The primary use of steroids in health care is to reduce inflammation and other disease
symptoms. This is because steroids make the whole immune system become less active
by some mechanism. This is useful and applicable to treat illness where there is an
immune component, for example painful joints and ligaments. Steroids cream are used
extensively in treating eczema, an inflammatory condition of the skin attended with
itching and the exudation of serous matter. The inhaler which is used to treat asthma
contains steroid, it has an important in reducing deaths from asthma.
Steroids are the ultimate anti-inflammatory drugs. They are prescribed or used
only when there is no other way to heal those diseases. The use of steroid in medicine is
limited due to very serious side effects in the body. This is the reason why steroids tend to
used usually in sprays and creams, which ensure a maximum steroid dose where it is
needed, and minimum levels in the blood stream.
6.2 Disadvantages of steroids
6.2.1. Serious Problems due to Steroids
Some people need constant prescription of steroid for medical reasons. Knowing
that we all need immune systems to fight infections and cancers, but this is always
destroyed by steroids. Probably these people are at risk of getting cancer, some of them
may be fatal. We see these patterns in those who receive organ transplants, who often
need huge doses of steroids to stop the body from destroying the donated tissue. Cancers
often develop, which shows us how important our white cells are in keeping us cancer-
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free, and how often all of us develop cancer in our daily lives. Most of us may have two
or three tiny cancers inside us at any time. Taking high dose steroids makes it more likely
one of these will develop rapidly.
People on high dose steroids are immune-deficient in every way so that many
organisms that rarely cause problems can overgrow, totally upsetting the normal balance
of mircobes in the body. An example is candida yeast which can grow rapidly in the
mouth causing painful thrush.
6.2.2. Misuse by Athletes/ Bodybuilders
Steroid is sometimes used illicitly by athletes to increase their strength. Those
athletes and bodybuilders who wish to get superiority over their counterparts have a
tendency of using them. The use of steroids among athletes is legally prohibited. An
athlete who takes steroids hormone before the competition can achieve higher levels of
performance and get an edge on the competition. In the view of moral, this is unfair for
other competitors. However, those who have taken steroid hormone can be clinically
tested. The ratio of using steroids is much higher in the bodybuilders as they have no
obligation to anyone of its use. In fact, anabolic steroids are not to be used without a
doctor's supervision and guidance. It could be fatal and cause certain side effects in the
human body, which begin over several days.
Many bodybuilders find it difficult to decide whether to use the steroids or not
considering its side effects with regard to their health. It is better to take the natural route
of bodybuilding rather than taking the route of using steroids.
The reason of why the steroid is not a good choice for bodybuilders is that as soon as the
bodybuilders leave the intake of steroids, the size of the muscles get reduced. Apart from
this, they also lose strength. It looks similar like someone filling air in a balloon and then
lets the air out of it. The use of steroids may give to instant results but it will get give side
effects over certain of time by endangering the body health.
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6.2.3. Health Hazards
Typical problems you will find in people who abuse anabolic steroids include
liver tumors and cancer, jaundice (yellow skin from liver failure), retention of fluid, high
blood pressure, heart attacks and strokes, increases in LDL (dangerous form of
cholesterol), kidney cancer, acne and trembling.
For men, the side effects include shrinking of the testicles, reduced sperm count,
infertility, baldness, development of breasts, increased risk for prostate cancer. For
women, steroid stimulate the growth of facial hair, male-pattern baldness, changes in or
cessation of the menstrual cycle, enlargement of the clitoris, deepened voice. For
adolescents, growth halted prematurely through premature skeletal maturation and
accelerated puberty changes. This means that adolescents risk remaining short for the
remainder of their lives if they take anabolic steroids before the typical adolescent growth
spurt.
6.2.4. Psychological Changes
Steroid also affects the brain. Scientific research shows that aggression and other
psychiatric side effects may result from abuse of anabolic steroids. Men and women
especially with the use of androgenic steroids, high dosages and long-term consumption,
can develop aggressive behavior.
The advantage of this is that one can train harder and more intensely. The
disadvantage is that some cannot properly cope with this, thus letting their aggressions
out on others. They become easily irritated, impatient, and inclined toward quick temper
and anger outbursts. In extreme cases this can lead to an increase in the use of violence
which has caused the breakup of relationships and marriages.
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Remarkable is that some male athletes using steroids can become depressive. The
cause for this may be the fact that these athletes tend to transform a considerable amount
of the consumed steroids into estrogens. One can explain the mood swings and
depressions with the known fact that the male hypothalamus reacts to the female
hormone estradiol. The supposition that steroids would make athletes psychically
dependent and, after their discontinuance, evoke withdrawal symptoms, is not totally
wrong. Those who press 400 pounds on the bench with the aid of steroids and then, after
discontinuing the substance, press only 360 pounds, then 320 pounds, and after a some
time only 300 pounds, can suffer problems with their ego. Many athletes simply forget
that the performance cannot remain at the same level without steroid use. In the
traditional sense, steroids are not habit forming.
7.0 CONCLUSIONS
Based on the variety of steroid structures we conclude that steroids can potentially
perform essential biological and physiological activity in nature. The subtle differences of
its structural activity relationship will determine the general application and uses of
steroids. It is believed that steroid in conjunction with its unique 4-membered rings
system is capable of contributing to the future research and developments. Modification
of the structures by other chemical residues may help to discover more alternative to
fulfill our daily needs. However, there are limitations of steroid that may influence the
user instead of benefits. Misuses of steroids are prone to sign effect and against the
legality. The instructions of steroids usage should be fully obeyed so that to get rid of the
unnecessary consequences.
We are satisfied with the attendance and contribution of each member of the group
except NIL.
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