title: Time course of changes in in vitro lipolysis of intra-abdominal fat depots in relation to high-fat diet-induced hepatic steatosis in rats.
abstract: The purpose of the present study was to determine the time course of changes in in vitro lipolysis and in perilipin content (Western blot) in the mesenteric and/or the retroperitoneal fat depots in relation to the development of hepatic steatosis in high-fat diet-fed rats. Female Sprague-Dawley rats were submitted to a high-fat diet (HF diet; 42 % as kJ) or a standard diet (SD diet) for 1, 2, 3 or 8 weeks. Fat accretion in the mesenteric and retroperitoneal tissues was higher (P<0.01) in HF diet-fed than in SD diet-fed rats as soon as 1 week after the beginning of the diet. Liver triacylglycerol concentrations were significantly (P<0.01) higher in HF diet-fed than in SD diet-fed rats throughout the experiment, the highest values being reached at week 2 of the diet. Basal and stimulated lipolysis (10(-4) to 10(-7) M-isoproterienol) in the mesenteric and retroperitoneal fat depots was not changed during the first 3 weeks, regardless of the diet. Lipolysis in the mesenteric adipose tissue in the basal and stimulated states was, however, higher (P<0.01) in HF diet-fed than in SD diet-fed rats after 8 weeks of the diets. There were no significant (P>0.05) effects of diet and time on perilipin content of mesenteric tissue. In spite of a rapid fat accretion, the present results do not provide any evidence of a rapid (3 weeks) increase in in vitro lipolysis in intra-abdominal fat depots upon the undertaking of an HF diet at a time where liver lipid infiltration is the most significant.
authors.affiliation: Département de kinésiologie, Université de Montréal, C.P. 6128, Succ. centre-ville, Montréal, Québec, Canada H3C 3J7.
authors.forename: Pascal
authors.initials: P
authors.lastname: Collin
authors.forename: Natalie
authors.initials: N
authors.lastname: Chapados
authors.forename: Elise
authors.initials: E
authors.lastname: Dufresne
authors.forename: Pierre
authors.initials: P
authors.lastname: Corriveau
authors.forename: Pascal
authors.initials: P
authors.lastname: Imbeault
authors.forename: Jean-Marc
authors.initials: JM
authors.lastname: Lavoie
mesh_terms: D017667:Adipocytes / Q000378:metabolism; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D001835:Body Weight; D002352:Carrier Proteins; D002478:Cells, Cultured; D004041:Dietary Fats / Q000008:administration & dosage*; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005234:Fatty Liver / Q000209:etiology / Q000378:metabolism* / Q000473:pathology; D005260:Female; D007328:Insulin / Q000097:blood; D050152:Intra-Abdominal Fat / Q000378:metabolism* / Q000473:pathology; D020738:Leptin / Q000097:blood; D008066:Lipolysis; D008099:Liver / Q000378:metabolism; D000070778:Perilipin-1; D010750:Phosphoproteins / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D001786:Blood Glucose; D002352:Carrier Proteins; D004041:Dietary Fats; D005230:Fatty Acids, Nonesterified; D007328:Insulin; D020738:Leptin; D000070778:Perilipin-1; D010750:Phosphoproteins