cholesterol synthesis

1. By Arnav Kaushal

2. Introduction
ž Cholesterol is constituent of all cell
membrane. Necessary for synthesis of
steroid hormones, bile salts and Vitamin
D. Normal level <200mg/dl.
Abnormality of cholesterol metabolism
may lead to cardiovascular disease and
heart attacks.

3. Functions of Cholesterol
ž Cholesterol packs phospholipids from both
the sides of cell membrane and therefore
maintains stability and stiffness of cell.
ž Cholesterol is responsible for proper
synthesis of neurotransmitters.
ž Cholesterol plays an important role in
synthesis of Vitamin D3 and hormones
including aldosterone, cortisol, estrogen,
cortisone, progesterone.
ž Cholesterol is a precursor to other vital
molecules that are important for functioning
of the body

4. Structure of cholesterol
ž Its molecular formula is C27H46O.
Cholesterol contains steroid rings with a
hydroxyl group, two methyl groups and
a hydrogen tail.

6. Synthesis
Biosynthesis of cholestrol is considered a Complex
method. The carbon atoms in cholestrol structure
provided by single precursor ACETYL CoA.
Synthesis of cholestol can be studied conveniently in
5 stages~
ž Formation of HMG CoA
ž Synthesis of mevalonate
ž Generation of isoprenoid units
ž Synthesis of squalene
ž Formation of cholesrol

9. Fate of Cholesterol
ž Cholesterol can be exported and
transported to other tissues via LDL
ž Converted to bile acids and secreted
into the intestines.
ž Used up in formation of cell membrane.
ž Used in formation of VIT.D and steroid
hormones.

10. QUESTION
Q)Ring system of cholesterol is
known as-
A) Cholanthrene ring
B) Cyclopentano phenanthrene
C) Napthoquinone
D) Corrin ring

11. key enzyme in pathway of
cholesterol biosynthesis is?

12. THANKS GENIUSES