Regulation of lipogenic enzymes by dietary unsaturated fatty acids in Ceratitis capitata larvae

Abstract

1. 1. Enzyme activities of acetyl-CoA carboxylase, fatty acid synthetase, fatty acid chain desaturation and elongation activities as well as the fatty acid incorporation activities into acylglycerols and phosphoglycerides, have been investigated after feeding diets high in either oleic acid or linoleic acid to larvae of the Dipterous Ceratitis capitata. 2. 2. Acetyl-CoA carboxylase and fatty acid synthetase activities were depressed in the larvae fed on the unsaturated fatty acid-rich diets; these enzyme activities were mostly influenced by either linoleic acid or oleic acid, respectively. 3. 3. Both unsaturated fatty acids, mainly linoleic acid, influenced both the desaturation and the elongation of palmitoyl-CoA. Microsomal and mitochondrial desaturation decreased markedly in both nutritional status; microsomal elongation was also decreased in both dietary conditions. 4. 4. The fatty acid incorporation into acylglycerols and phosphoglycerides was mainly modified in the microsomal fraction by the unsaturated fatty acids. The diminution of the incorporation was mainly carried out by the linoleic acid-rich diet.