Gagnon RS 1- Lipid Metabolism Flashcards
What is the carnitine shuttle? How does it regulate lipid metabolism?
Fatty acids are transported from the cytosol to the inner mitochondrial matrix via the carnitine transporter.
Malonyl-CoA inhibits fatty acid this transporter to prevent beta oxidation
What is the inheritance pattern of diseases associated with beta oxidation?
Autosomal recessive
What is Wolman Disease?
A autosomal recessive disease characterized by a deficiency of lysosomal acid lipase
What is hormone sensitive lipase?
An enzyme located in adipocytes that releases fatty acids and glycerol
What is lipoprotein lipase?
A lipase that is attached non-covalently to the capillary endothelial cells.
What is hepatic lipase?
A lipase found in the liver, attached to the surface of hepatocytes by heparin sulfate proteoglycans. Releases fatty acids from TAG’s to form DAG’s.
Why do low levels of oxaloacetate cause a build-up of acetyl-CoA?
The first reaction in the TCA cycle is oxaloacetate binding to acetyl-CoA.
Why is oxaloacetate low the fasting state?
It is pulled away from the TCA cycle and instead used in gluconeogenesis.
What enzyme is the liver missing which prevents it from utilizing ketone bodies?
Succinyl-CoA transferase
What exogenous substances regulate the expression of genes that control lipid metabolism?
Hormones
How do citrate and palmitoyl-CoA regulate acetyl-CoA carboxylase?
Citrate stimulates acetyl-CoA carboxylase, while palmitoyl-CoA inhibits it
