lipids (kwon)

what is the vital structural component of cell membranes?

cholesterol

cholesterol is mainly synthesized where?

in the liver

what enzymes does cholesterol synthesis in the liver involve?

HMG-CoA reductase

_______ forms a bilayer and outer layer of lipoprotiens, they also protect the cell maintain chemical and electrical gradients

phospholipids

what is the major dietary fat and are also the main storage form of fuel?

triglycerides

in periods of reduce calorie intakes, ______ are released from triglycerides

fatty acids

what are the components that make up a micelle?

-bile salts

-monoglycerides

-fatty acids

-phospholipids

-cholesterol

what is the functions of lipoprotiens?

deliver fat molecules to the cells that need it

what are the components of lipoproteins?

-cholesterol ester + triacylglycerol (core)

-apoplipoprotien

-phospholipids

What are the types of lipoproteins?

-chylomicrons

-VLDL

-LDL

-HDL

which is the biggest lipoprotein? which is the smallest?

chylomicrons; HDLs

what are the core lipids of chylomicrons? what is the ratio?

-dietary triglycerides and cholesterol esters; 10:1

what are the core lipids of VLDLs? what is the ratio?

endogenous triglycerides and cholesterol esters; 5:1

LDLs and HDLs contain which types of core lipids

cholesteryl esters

which lipoprotiens contain apolipoproteins C and E?

chylomicrons and HDLs, VLDL (E only)

which lipoprotiens contain apolipoprotien B-100?

VLDL and LDL

what is the function of chylomicrons?

transport dietary lipids from the gut to the adipose tissue, muscle, and liver

where are chylomicrons formed?

in the gut wall

chylomicrons deliver ______ to the adipose tissue via the action of ______ located in the vascular endothelial cells

TG; LPL (lipoprotein lipase)

chylomicron remnants are taken into _______

the liver

VLDL is formed in the ______ and secreted into the circulation

liver

what is the function of VLDL?

receive apolipoproteins C and E from HDL

VLDLs are transformed into ______ and ________

IDL and LDL

What is the function of LDL?

transports cholesterol to peripheral tissues

T/F: LDL can deliver cholesterol to nascent atheroma.

true

HDLs are formed in the _____

gut and the liver

T/F: the high density of HDLs is caused by the large ratio of lipid to protein

false (protein to lipids)

HDLs acquire cholesterol from _______

peripheral tissues and atheroma

HDLs are taken into the _______

liver

______ % of bile salts are excreted in feces

5

what are the causes of dyslipidemia?

-biochemical defects in lipoprotein metabolism

-excessive dietary intake of lipids

-endocrine abnormalities

-drugs that perturb lipoprotein formation or catabolism

types of hypercholesterolemia

-familial hypercholesterolemia: defects in LDL receptor

-familial defective apoB-100

-polygenic hypercholesterolemia

mutation in apoB-100 lead to ______ affinity of the LDL particles for ______ receptors

decreased affinity; LDL receptors

types of hypertriglyceridemia

-familial hypertriglyceridemia

-familial LPL deficiency

-ApoCII deficiency

familiar hypertrigleridemia causes _____ hepatic TG synthesis, _____ lipolysis of chylomicron and VLDL

increased; decreased

what is the cause of familial LPL deficiency?

elevated chylomicrons during infancy and impaired removal of VLDL later in life

______ is the cofactor for LPL

ApoCII

what is the function of cholesteryl ester transfer protein (CETP)?

facilitates exchange of cholesteryl esters between HDL and LDL

CEPT deficiency ______ HDL-C levels

increases

disorders of HDL metabolism includes

-ABCa1 (ATP cassette protein A1) defect

-LCAT (lecithin cholesterol acyltransferase) deficiency

-ApoA1 deficiency

what is the function of lecithin cholesterol acyltransferase (LCAT)?

converts cholesterol to cholesteryl ester

what is the cofactor for LCAT?

ApoA1

what is ATP binding cassette protein?

a cholesterol efflux pump

torcetrapib inhibits ______. it increased HDL levels, but it caused HTN, no change in atherosclerosis, and increased cardiovascular events

CETP