(3.2) Cholesterol and Lipid Metabolism

Question 1

What is the pathology of Famalial Hypeerlipidaemia? Suggest a treatment for it.

Answer 1

• Mutation of LDL receptor -> increased LDL (moving cholesterol from liver to tissue) in circulation
• Statin: increases LDL receptors and inhibits HMG-CoA reductase -> reduces Cholesterol synthesis

Question 2

What is the normal range of Cholesterol and when fasting?

Answer 2

• Normal:

Question 3

Suggest some ADRs of Statin use.

Answer 3

• Myopathy & Myositis
• Headache
• GI complaints
• Type 2 Diabetes

Question 4

Suggest two types of Statin and how should each be prescribed (e.g. time of a day)?

Answer 4

• Simvastatin: given before bed (a short half life, to coincide cholesterol peak production in the morning)
• Rosuvastatin & Atorvastatin: during day (a longer half life, given to those who don’t take before bed)

Question 5

How do Fibrates work?

Answer 5

PPAR-alpha antagonists -> + FA uptake & oxidation & action of lipoprotein lipase -> —TAG & -LDL

Question 6

Suggest some possible ADRs of fibrates.

Answer 6

• GI complaints
• Myositis
• Cholelithiasis

Question 7

Why shouldn’t Statin and Fibrates be prescribed together?

Answer 7

Both cause myopathy -> Rhabdomyolysis

Question 8

How does Ezetimibe work?

Answer 8

Cholesterol lipase inhibitor -> inhibits INTESTINAL cholesterol absorption -> –LDL

Question 9

Suggest some possible ADRs of Ezetimibe.

Answer 9

• Headache
• GI complaints
• Headache
• Rhabdomyolysis

Question 10

Suggest the actions of Nicotinic Acid.

Answer 10

• —TAG
• -LDL
• +++HDL

Question 11

Suggest some possible ADRs of Nicotinic Acid.

Answer 11

• Headache
• Flushing
• Hepatoxicity
• Reduced insulin sensitivity -> hyperglycaemia

Question 12

How does Bile Acid Sequesterants work?

Answer 12

• Bind bile acid -> reduce their reabsorption
• Bile acid synthesis requires cholesterol, reduced reabsorption leading to increased synthesis -> increase utilisation of cholesterol -> lowers cholesterol level