Effects of dietary fat energy restriction and fish oil feeding on hepatic metabolic abnormalities and insulin resistance in KK mice with high-fat diet-induced obesity.
We investigated the effects of dietary fat energy restriction and fish oil intake on glucose and lipid metabolism in female KK mice with high-fat (HF) diet-induced obesity. Mice were fed a lard/safflower oil (LSO50) diet consisting of 50 energy% (en%) lard/safflower oil as the fat source for 12 weeks. Then, the mice were fed various fat energy restriction (25 en% fat) diets - LSO, FO2.5, FO12.5 or FO25 - containing 0, 2.5, 12.5, or 25 en% fish oil, respectively, for 9 weeks. Conversion from a HF diet to each fat energy restriction diet significantly decreased final body weights and visceral and subcutaneous fat mass in all fat energy restriction groups, regardless of fish oil contents. Hepatic triglyceride and cholesterol levels markedly decreased in the FO12.5 and FO25 groups, but not in the LSO group. Although plasma insulin levels did not differ among groups, the blood glucose areas under the curve in the oral glucose tolerance test were significantly lower in the FO12.5 and FO25 groups. Real-time polymerase chain reaction analysis showed fatty acid synthase mRNA levels significantly decreased in the FO25 group, and stearoyl-CoA desaturase 1 mRNA levels markedly decreased in the FO12.5 and FO25 groups. These results demonstrate that body weight gains were suppressed by dietary fat energy restriction even in KK mice with HF diet-induced obesity. We also suggested that the combination of fat energy restriction and fish oil feeding decreased fat droplets and ameliorated hepatic hypertrophy and insulin resistance with suppression of de novo lipogenesis in these mice.
Department of Clinical Dietetics and Human Nutrition, Faculty of Pharmaceutical Sciences, Josai University, Saitama 350-0295, Japan.
Takeshi
T
Arai
Hyoun-ju
HJ
Kim
Satoshi
S
Hirako
Maki
M
Nakasatomi
Hiroshige
H
Chiba
Akiyo
A
Matsumoto
D000273:Adipose Tissue / Q000187:drug effects; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D001835:Body Weight / Q000187:drug effects; D002784:Cholesterol / Q000378:metabolism; D018752:Diet, Fat-Restricted; D059305:Diet, High-Fat / Q000009:adverse effects; D004041:Dietary Fats / Q000494:pharmacology; D064429:Fatty Acid Synthases / Q000235:genetics; D005260:Female; D005395:Fish Oils / Q000494:pharmacology*; D005786:Gene Expression Regulation / Q000187:drug effects; D007333:Insulin Resistance; D050356:Lipid Metabolism / Q000187:drug effects; D008099:Liver / Q000187:drug effects / Q000378:metabolism*; D051379:Mice; D009765:Obesity / Q000178:diet therapy* / Q000209:etiology / Q000378:metabolism*; D012450:Safflower Oil / Q000494:pharmacology; D013230:Stearoyl-CoA Desaturase / Q000235:genetics; D014280:Triglycerides / Q000378:metabolism
D001786:Blood Glucose; D004041:Dietary Fats; D005395:Fish Oils; D014280:Triglycerides; D012450:Safflower Oil; D002784:Cholesterol; D013230:Stearoyl-CoA Desaturase; D064429:Fatty Acid Synthases; C029310:lard