CHOLESTEROL METABOLISM AND RISKS Flashcards by juliana lluch

a parent structure of cholesterol

cyclopentanoperhydrophenanthrene

How well did you know this?

Not at all

Perfectly

functions of cholesterol

Cholesteryl esters
lipoproteins
bile salts
vitamin d
steroids hormones
membrane formation

How well did you know this?

Not at all

Perfectly

The largest contribution in biosynthesis of cholesterol is made by

LIVER (50%),
INTESTINE (15%),
SKIN,
ADRENAL CORTEX,
REPRODUCTIVE TISSUES.

How well did you know this?

Not at all

Perfectly

The enzymes involved in the synthesis are found in the ________ and _______ fractions of the cells.

CYTOSOL
MICROSOMAL

How well did you know this?

Not at all

Perfectly

provides the carbon atoms in the
cholesterol.

acetyl coa

How well did you know this?

Not at all

Perfectly

required for production of 1 mole of cholesterol

1 8 moles of Acetyl CoA
3 6 m o l e s o f ATP
/ 16 moles of NADPH

How well did you know this?

Not at all

Perfectly

Steps of the Cholesterol Synthesis

• Formation of HMG CoA
• Formation of Mevalonate (6C)
• Production of Isoprenoid units (5C)
• Synthesis of Squalene
• Conversion of …..
Squalene to Cholesterol (27C

How well did you know this?

Not at all

Perfectly

the rate limiting enzyme
in cholesterol biosynthesis.

HMG-CoA reductase

How well did you know this?

Not at all

Perfectly

different kinds of metabolic control:

Feedback Regulation
* Hormonal Regulation
* Nutritional Regulation

How well did you know this?

Not at all

Perfectly

Competitive inhibitor drugs of HMG-CoA reductase:

Pravastatin
Lovastatin
Mevastatin
Simvastatin
Fluvastatin

How well did you know this?

Not at all

Perfectly

Degradation of Cholesterol important products

Bile acids & Bile Salts
Steroid Hormones
Vitamin D

How well did you know this?

Not at all

Perfectly

primary bile acids

cholic acid
chenodeoxycholic acid

How well did you know this?

Not at all

Perfectly

The primary bile acids are conjugate with
glycine and taurine to form

Glycocholicacid
Taurocholic acid
Glycochenodeoxycholic acid
Taurochenodeoxycholic acid

How well did you know this?

Not at all

Perfectly

a process that involves the movement of substances from the liver to the small intestine and back again

enterohepatic circulation

How well did you know this?

Not at all

Perfectly

responsible for keeping the
cholesterol in bile in the soluble
state.

Bile salts and phospholipids

How well did you know this?

Not at all

Perfectly

Due to their deficiency of the gall bladder leads to the accumulation of cholesterol
crystals in the gall bladder.
• This condition is known as

cholelithiasis

Patients with this condition are responds to the
administration of the bile acid chenodeoxycholic
acid known as _______.

CHENODIOL

the precursor for the synthesis of all the
five classes of steroid hormones

cholesterol

five classes of steroid hormones

Glucocorticoid
• Mineralocorticoids
• Progesterones
• Androgens
• Estrogens

responsible for the transport and elimination of cholesterol from the body.

HDL and the enzyme LCAT

a plasma enzyme synthesized in liver.

LCAT

Plasma cholesterol is associated with the different forms of
lipoprotein fractions like:

HDL (40 to 60 mg/dl)
LDL (less than130 mg/dI)
VLDL (1/5th of TGL

HYPERCHOLESTEROLEMIA
This condition is associated with the
following:

DM
Hypothyroidism
Obstructive Jaundice
Nephrotic Syndrome
CHD
ARTHEROSCLEROSIS

Control of Hypercholesterolemia

Consumption of PUFA
• Dietary Cholesterol
• Dietary fibre
• Avoid high Carbohydrate
• Impact life style
•Moderate alcohol consumption
Uses of drugs

It is characterized by intimal lesions called atheromas (also called atheromatous or atherosclerotic plaques), that protrude into vascular lumina.

A t h e r o s c l e r o s i s

a slow and progressive building up of plaque, fatty substances, cholesterol, cellular waste products, calcium and fibrin

atherosclerosis

a type of fat normally found in the bloodstream.

cholesterol

what are the different types of cholesterol in the blood

hdl and ldl cholesterol

a type of fat found in the blood that provide fuel to help with daily activities, just as a car needs gasoline to function properly.

triglycerides

the combination of LDL-C, VLDL-C and HDL-C.

total cholesterol

This is called the "bad" cholesterol.

Low-density lipoprotein (LDL) cholesterol.

This is called the "good" cholesterol because it helps carry away LDL cholesterol, thus keeping arteries open and your blood flowing more freely.

High-density lipoprotein (HDL) cholesterol.

This is a type of cholesterol that's usually present in very low amounts when the blood sample is a fasting samples since it's mostly comes from food you've recently eaten.

Very low-density lipoprotein (VLDL) cholesterol: