Diet fat alters synaptosomal phosphatidylethanolaminemethyl-transferase activity and phosphatidylcholine synthesis in brain
Phosphatidylcholine (PC) can be synthesized via three routes, each having potentially different metabolic fates. One route for PC synthesis is methylation of phosphatidylethanolamine (PE). To examine if dietary fat affects membrane PE composition and phosphatidylethanolaminemethyltransferase (PEMT) activity, male weanling rats were fed semi-purified diets containing 20% (w/w) fat of differing fatty acid composition for 24 days. Microsomal and synaptic plasma membranes were isolated and phospholipid composition analyzed. PEMT activity was measured by incorporation of the methyl group from /sup 3/H-S-adenosylmethionine into PE. Polyunsaturated diets high in omega 6 fatty acids produce a high ratio of omega 6/omega 3 fatty acids in synaptic plasma membranes. Dietary omega 3 and omega 6 fatty acid levels are reflected in membrane phospholipid content of 22:6(3), 20:4(6), 22:4(6) and 22:5(6). Diet-induced increase in these longer chain homologues of omega 6 and omega 3 fatty acids and a high ratio of omega 6/omega 3 fatty acids in PE are both associated with increased PEMT activity. These results suggest that diet-fat induced change in fatty acid composition of membrane PE results in transition in PEMT activity and synthesis of PC in brain, by providing preferred species of PE for methylation.
- Research Organization:
- Univ. of Alberta, Edmonton
- OSTI ID:
- 6845521
- Report Number(s):
- CONF-8604222-
- Journal Information:
- Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States), Vol. 45:4; Conference: 70. annual meeting of the Federation of American Society for Experimental Biology, St. Louis, MO, USA, 13 Apr 1986
- Country of Publication:
- United States
- Language:
- English
Similar Records
Biosynthesis of glycerolipid molecular species in photoreceptor membranes of frog retina
Adenylate cyclase activity, (/sup 3/H)-dihydroalprenolol binding and fatty acid composition of rat heart membranes in essential fatty acid deficiency
Related Subjects
CELL MEMBRANES
CHEMICAL COMPOSITION
PHOSPHOLIPIDS
BIOSYNTHESIS
TRANSFERASES
ENZYME ACTIVITY
BRAIN
CARBOXYLIC ACIDS
DIET
METABOLISM
MICROSOMES
RATS
TRACER TECHNIQUES
TRITIUM COMPOUNDS
ANIMALS
BODY
CELL CONSTITUENTS
CENTRAL NERVOUS SYSTEM
ENZYMES
ESTERS
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
LIPIDS
MAMMALS
MEMBRANES
NERVOUS SYSTEM
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC PHOSPHORUS COMPOUNDS
ORGANOIDS
ORGANS
RODENTS
SYNTHESIS
VERTEBRATES
550501* - Metabolism- Tracer Techniques