Co-induction by peroxisome proliferators of microsomal 1-acylglycerophosphocholine acyltransferase with peroxisomal beta-oxidation in rat liver.
Administration of clofibric acid, 2,2'-(decamethylenedithio)diethanol, di(2-ethylhexyl)phthalate or perfluorooctanoic acid to male rates increased markedly microsomal 1-acylglycerophosphocholine (a-acyl-GPC) acyltransferase in a dose-dependent manner in liver. Simultaneous administration of actinomycin D or cycloheximide completely abolished the increase in the enzyme activity. The treatment of rats with clofibric acid did not affect the rate of decay of 1-acyl-GPC acyltransferase. Regardless of a great difference in the chemical structures of the peroxisome proliferators, high correlation was observed between the induced activities of microsomal 1-acyl-GPC acyltransferase and peroxisomal beta-oxidation. Stearoyl-CoA desaturase was induced by peroxisome proliferators in a dose-dependent manner; nevertheless, high correlation was not seen between the induced activities of desaturase and peroxisomal beta-oxidation. Hormonal (adrenalectomy, diabetes, hyperthyroidism and hypothyroidism) and nutritional (starvation, starvation-refeeding, fat-free diet feeding and high-fat diet feeding) alterations hardly affected the activity of 1-acyl-GPC acyltransferase. The present results indicate that microsomal 1-acyl-GPC acyltransferase is a useful parameter responsive to the challenges by peroxisome proliferators and suggest that a similar regulatory mechanism operates for the inductions of microsomal 1-acyl-GPC acyltransferase and peroxisomal beta-oxidation.
Kawashima
Y
Y
Faculty of Pharmaceutical Sciences, Toyama Medical and Pharmaceutical University, Japan.
Horii
S
S
Matsunaga
T
T
Hirose
A
A
Adachi
T
T
Kozuka
H
H
D008243:1-Acylglycerophosphocholine O-Acyltransferase; D000217:Acyltransferases / Q000096:biosynthesis*; D000818:Animals; D004790:Enzyme Induction / Q000187:drug effects; D000960:Hypolipidemic Agents / Q000494:pharmacology*; D066298:In Vitro Techniques; D008297:Male; D008830:Microbodies / Q000187:drug effects* / Q000201:enzymology; D008862:Microsomes, Liver / Q000187:drug effects / Q000201:enzymology*; D010084:Oxidation-Reduction; D051381:Rats; D011919:Rats, Inbred Strains; D013230:Stearoyl-CoA Desaturase / Q000378:metabolism
D000960:Hypolipidemic Agents; D013230:Stearoyl-CoA Desaturase; D000217:Acyltransferases; D008243:1-Acylglycerophosphocholine O-Acyltransferase