week 9a- dietary cholesterol

food sources of cholesterol

chicken, fish, beef, pork, eggs, milk, and beef liver which is so high due to the central role the liver plays for cholesterol metabolism in the body

corn as source of cholesterol

have plant based equivalent to cholesterol, plant sterols, look very similar and have overlapping pathways

cellular cholesterol pools

free cholesterol in the cell membrane; cholesterol ester which has a fatty acid attached by an ester bond, more storage pool

cholesterol and heart disease risk

blood cholesterol increases CVD risk; relationship between dietary cholesterol intake and CVD risk is less clear

cholesterol digestion

in order for cholesterol to be absorbed, it must be in it’s free form, enzyme required for this is CEH

cholesterol ester hydrolase (CEH)

pancreatic origin, broad specificity (cholesterol ester, triglycerides, and phospholipids)

mixed micelle

not absorbed, vehicle to get lipids through water layer to BBM

cholesterol absorption- NPC1L1

found in intracellular compartment, localizes to BBM when intracellular is CH low, endocytosis, target of ezetimibe (cholesterol lowering drug)

cholesterol absorption- ABCG5/G8

cholesterol efflux, primary active transport, also transports sterols, mutations cause sitosterolemia

sitosterolemia

hyper absorption of plant sterols, increased risk of heart disease