In well fed state which of the following inhibit CPT1 on outer membrane of mitochondria (AIIMS Nov 2011)
a. Inhibitor of the carnitine shuttle: Malonyl CoA inhibits CPT-I, thus preventing the entry of long-chain acyl groups into the mitochondrial matrix. Therefore, when fatty acid synthesis is occurring in the cytosol (as indicated by the presence of malonyl CoA), the newly made palmitate cannot be transferred into the mitochondria and degraded.
b. Fatty acid oxidation is also regulated by the acetyl CoA to CoA ratio: As the ratio increases, the thiolase reaction decreases.
c. [Note: The phosphorylation and inhibition of acetyl carboxylase decreases malonyl CoA production, removing the break on fatty acid oxidation.]