K4 Triacylglycerols

Structure Triacylglycerols (fats or triglycerides) consist of three fatty acid chains 

Breakdown The fatty acids in triacylglycerols are released from the glycerol backbone by the action of lipases. The free fatty acids can then be degraded by (3-oxidation to produce energy. The glycerol is converted into dihydroxyacetone phosphate which enters glycolysis. 

Regulation The concentration of free fatty acids in the blood is controlled by the rate at which hormone-sensitive triacylglycerol lipase hydrolyzes the triacylglycerols stored in adipose tissue. Glucagon, epinephrine and norepinephrine cause an increase in the intracellular level of cAMP which allosterically activates cAMP-dependent protein kinase. The kinase in turn phosphorylates hormone-sensitive lipase, activating it, and leading to the release of fatty acids into the blood. Insulin has the opposite effect it decreases the level of cAMP which leads to the dephosphorylation and inactivation of hormone-sensitive lipase. 

Related topics Fatty acid breakdown (K2) Lipoproteins (K6) Fatty acid synthesis (K3) 

Structure and Triacylglycerols (also called fats or triglycerides) consist of three fatty acid function chains esterified to a glycerol backbone. Simple triacylglycerols have three 

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