CVS - Lipid homeostatis

Question 1

What is hyperlipidaemia?

Answer 1

high cholesterol, means you have too many lipids (fats) in your blood

Question 2

hypercholesterolemia

Answer 2

high cholesterol content.

Question 3

hyperapobetalipoproteinemia

Answer 3

high levels of apolipoprotein B, which is part of LDL cholesterol.

Question 4

What is bad cholestrol called?

Answer 4

LDL

Question 5

What is the genetic type of hyperlipidaemia?

Answer 5

hyperlipidaemia
hypercholestrerolemia
hyperapobetaliprotieinemia

Question 6

What is the secondary type of hyperlipidaemia caused by
?

Answer 6

• obesity
  smoking
  high fat diet
  alochol

Question 7

LIPID-LOW
means

Answer 7

1. Cholesterol synthesis inhibition
2. Intestinal absorption
3. Lipoprotein lipase activity
4. HDL

Question 8

Cholesterol synthesis inhibition:

Answer 8

• statins competitively inhibit the HMG-CoA reductase > reduced cholesterol

-Then liver recruits MORE LDL from circulation > LDL clearance from the blood

Question 9

What are CYP inhibitors?

Answer 9

• grapefruit juice
• diltiazem
• amlodipine
• macrolide antibiotics

worsen statin adverse effects

Question 10

What are the 1st line therapy for CVD?

Answer 10

• atorvastatin
• pravastatin
• rosuvastatin
  -simvastatin

Question 11

How does cholesterol absorption inhibition work? give an example

Answer 11

• anion exchange resins:
  binds with bile salts (insoluble complex) > excreted in faeces

EZETIMDE - block the transport protein Niemann-Pick C1 (in gut wall)

Question 12

What is the outcome of cholesterol absorption inhibition?

Answer 12

reduced intestinal

cholestrol absorption

cholestrol directed to

compensate for bile loss
LDL cholestrol clearance

Ezetimibe - reduces intestinal cholestrol absorption, without affecting bile

Question 13

coronary thrombosis

Answer 13

myocardial infarction (MI)

Question 14

Cholesterol

Answer 14

an essential component that makes the cell membrane and modulates membrane fluidity, and critical for cell growth and viability; Precursor for steroid hormones, vitamin D and bile salts

Question 15

Triglycerides

Answer 15

largely through diet, but synthesised in the liver as well. supply energy/fuel to muscle and other tissues

Question 16

How is cholesterol absorbed and transported to the liver?

Answer 16

absorbed by micelles into intestinalw all throigh identified protein channels
bile EMULSIFIES dietery lipids (incl cholestrol), facilitates absorption, salts are recycled via hepatic portal vein (entero-hepatic circulation)

SOME chol. pumped out fo body > away into intestinal lumen by heterodimeric ATP- binding cassette transporter protein complex

Question 17

Conversion of HMG-CoA to mevaolnate can be stopped, how?

Answer 17

by blocking enzyme, stop secretion of cholestrol

Question 18

are chol and triglycerides soluble of insoluble in water?

Answer 18

INSOLUBLE - require carrier protein

Question 19

Characteristics of lipoproteins

Answer 19

central core containing cholesterol esters (hydrophobic)
triglycerides surrounded by free cholesterol, phospholipids (amphophilic)
apolipoproteins, facilitate lipoprotein formation and function
AMPOPHILIC – MIXTURE OF HYDROPHOBIC AND HYDROPHILIC
In core phobic, out phobic – this is how it can move in the blood

Question 20

Chylomicrons

Answer 20

triglyceride-rich particles made byintestine, transports triglycerides/choletsrol to PERIPHERL tissues and liver

Question 21

Chylomicron remnants

Answer 21

removal of trigloyceride from chylomicrons by peripheral tissues results in smaller

Question 22

Intermediate-density lipoproteins (IDL; VLDL remnants)

Answer 22

removal of triglycerides from VLDL by MUSCLE and adipsose tissue results in formation of iDL particles – enriched in cholesterol

Question 23

sLDL particles

Answer 23

decreased affinity for the LDL receptor resulting in a prolonged retention time in the circulation

Question 24

How does sLDL get trapped in arterial wall?

Answer 24

easily enters the arterial wall and binds more avidly to intsa-arterial proteoglycans

Question 25

are sLDL suitable for oxidation?

Answer 25

yes > results in an enhanced uptake by macrophages

Question 26

HDL, good or bad?

Answer 26

good
- antiapoptotic
- dec, expression of adesion molecules (anti-inflammatory)
- dec LDL oxidation
- ameliorates endothelial function

Question 27

what do HDL particles contain?

Answer 27

cholestrol and phospholipids

apo A-I is the core structural protein and each - HDL particle may contain multiple Apo A-I moleucles

high levels of Apo-I + atherosclerosis

Question 28

Pathophysiology of atherosclerosis

Answer 28

1) endothelial dysfunction
2) formation of lipid layer or fatty streak within the intima
3) migration of leukocytes and smooth muscle cells into the vessel wall
4) foam cell formation
5) degradation of extracellular matrix

Question 29

Increased LDL

Answer 29

plaque rupture