Lipids pt 2

Circulating _ are carried in lipoprotein particles with specific apolipoproteins

Lipids Core: Contains

Lipids Surface: Holds

Lipids Transport and clearance depend on: (2)

TAG and cholesterol are absorbed in the

Lipid Absorption These are packaged into _ → enters the blood via the lymph and the thoracic duct

Lipid Absorption As CMs circulate, lipoprotein lipase (LPL) breaks down TAG into _

Lipid Absorption Fatty acids are taken up by

Lipid Absorption CMs shrink and become remnants, which are taken up by the

Lipid Absorption In the endogenous pathway, production of TAG from FA by the liver take place, with synthesis of VLDL particles containing

Lipid Absorption VLDL is converted by LPL into IDL, then to

Lipid Absorption _ delivers cholesterol to liver and other tissues (for membranes & steroid production)

Lipid Absorption collects cholesterol from tissues → returns it for reuse or excretion in bile

Lipid Absorption can also transfer cholesterol to VLDL for further metabolism

Enzymes that participate in Lipoprotein Metabolism (Lipolytic Enzymes) Breaks down triglycerides (TAGs) in lipoproteins into fatty acids and glycerol; found on capillary walls in fat tissue, heart, and muscles

Enzymes that participate in Lipoprotein Metabolism (Lipolytic Enzymes) hydrolyzes TAG and phospholipids from HDL; hydrolyzes lipids on VLDL and IDL; mainly active on the liver

Enzymes that participate in Lipoprotein Metabolism (Lipolytic Enzymes) Converts free cholesterol in HDL into cholesteryl esters, allowing HDL to store cholesterol.

Enzymes that participate in Lipoprotein Metabolism (Lipolytic Enzymes) Breaks down phospholipids and TAGs in HDL; found in endothelial (blood vessel) cells

Enzymes that participate in Lipoprotein Metabolism (Lipolytic Enzymes) Moves cholesterol out of cells into HDL, starting reverse cholesterol transport

large complexes of lipids and proteins (called apolipoproteins).

Main function: Transport triglycerides (TAGs) and cholesterol to where they’re stored or used for energy

TAGs and cholesterol don’t float freely in blood → they travel as part of water-soluble lipoproteins

Lipoproteins needs chylomicrons for absorption and uses VLDL and LDL to reach body tissues

It helps to keep the lipids in solution (solubility) during circulation through the bloodstream.