Evaluation of liver fatty acid oxidation in the leptin-deficient obese mouse.
We hypothesized that liver fatty acid oxidation (FAO) is compromised in the leptin-deficient obese (Lep(ob)/Lep(ob)) mouse model, and that this would be further challenged when these mice were fed a high-fat diet. Obese mice had a 3.8-fold increased body fat content and a 9-fold increased liver fat content as compared to control mice when both groups were fed a low-fat diet. The expression of liver FAO enzymes, carnitine palmitoyltransferase-1a, long-chain acyl-CoA dehydrogenase, medium-chain acyl-CoA dehydrogenase, and short-chain acyl-CoA dehydrogenase, was not affected in obese mice as compared to controls on either a low-fat or a high-fat diet. The expression of very-long-chain acyl-CoA dehydrogenase was elevated in obese mice on the control diet, as compared to control mice. For all measures evaluated, increasing the level of fat in the diet had a smaller effect than leptin deficiency. In summary, despite obese mice having an excess of fat available for mitochondrial beta-oxidation in liver, overall energy balance appeared to dictate that the net liver FAO remained at control levels.
Brix
Amy E
AE
Departments of Genomics and Pathobiology, University of Alabama at Birmingham, Birmingham, Alabama 35294, USA.
Elgavish
Ada
A
Nagy
Tim R
TR
Gower
Barbara A
BA
Rhead
William J
WJ
Wood
Philip A
PA
D042964:Acyl-CoA Dehydrogenase; D044942:Acyl-CoA Dehydrogenase, Long-Chain / Q000235:genetics / Q000378:metabolism; D000273:Adipose Tissue / Q000378:metabolism; D000704:Analysis of Variance; D000818:Animals; D015152:Blotting, Northern; D015153:Blotting, Western; D001835:Body Weight / Q000187:drug effects; D002334:Carnitine O-Palmitoyltransferase / Q000235:genetics / Q000378:metabolism; D004041:Dietary Fats / Q000008:administration & dosage; D005227:Fatty Acids / Q000378:metabolism*; D005260:Female; D020738:Leptin / Q000172:deficiency* / Q000235:genetics; D008055:Lipids / Q000097:blood; D008099:Liver / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D008820:Mice, Obese; D009765:Obesity / Q000235:genetics / Q000378:metabolism*; D009929:Organ Size / Q000187:drug effects; D010084:Oxidation-Reduction; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D013047:Specific Pathogen-Free Organisms; D013997:Time Factors
D004041:Dietary Fats; D005227:Fatty Acids; D020738:Leptin; D008055:Lipids; D012333:RNA, Messenger; D042964:Acyl-CoA Dehydrogenase; D044942:Acyl-CoA Dehydrogenase, Long-Chain; D002334:Carnitine O-Palmitoyltransferase