Frontier Science Research Center, University of Miyazaki, Miyazaki 889-1692, Japan.
Obes Res Clin Pract. 2013 Jul-Aug;7(4):e243-50. doi: 10.1016/j.orcp.2013.01.004.
We assessed the metabolic characteristics of high-fat-diet-resistant (DR) rats.
Body weight, energy intake, locomotor activity, oxygen consumption, plasma leptin and lipid levels, size of visceral-fat adipocytes, and mRNA levels of genes related to lipid metabolism were measured in control rats fed standard chow and in obesity-prone (high-fat-diet-induced obesity, DIO) and DR rats fed a high-fat diet. Glucose tolerance and insulin tolerance tests were also performed.
DIO rats gained weight more rapidly than did DR and control rats; DR rats gained less weight than did DIO rats despite similar energy intake. Energy expenditure did not differ among the three groups. The diameter of visceral-fat adipocytes was similar in DR and control rats. mRNA levels of genes involved in lipogenesis, such as fatty acid synthase and acetyl-CoA carboxylase, tended to be lower in DR than in control and DIO rats, whereas those of carnitine palmitoyltransferase 1a, which is involved in fatty acid β-oxidation, were greater in DR rats than in the other groups. DIO rats showed hyperinsulinemia and glucose intolerance, whereas DR rats had high sensitivity to insulin.
DR rats show suppression of lipogenesis and acceleration of fatty acid β-oxidation in the visceral fat. These characteristics likely contribute to the anti-obesity phenotype of DR rats.
评估高脂肪饮食抵抗（DR）大鼠的代谢特征。
在给予标准饲料的对照组大鼠和易肥胖（高脂肪饮食诱导肥胖，DIO）大鼠和给予高脂肪饮食的 DR 大鼠中，测量体重、能量摄入、运动活性、耗氧量、血浆瘦素和脂质水平、内脏脂肪脂肪细胞大小以及与脂质代谢相关的基因的 mRNA 水平。还进行了葡萄糖耐量和胰岛素耐量测试。
DIO 大鼠比 DR 和对照组大鼠体重增加更快；尽管能量摄入相似，但 DR 大鼠体重增加较少。三组之间的能量消耗没有差异。DR 和对照组大鼠的内脏脂肪脂肪细胞直径相似。参与脂肪生成的基因，如脂肪酸合酶和乙酰辅酶 A 羧化酶的 mRNA 水平在 DR 大鼠中趋于低于对照组和 DIO 大鼠，而参与脂肪酸β-氧化的肉碱棕榈酰转移酶 1a 的 mRNA 水平在 DR 大鼠中高于其他组。DIO 大鼠表现出高胰岛素血症和葡萄糖不耐受，而 DR 大鼠对胰岛素的敏感性较高。
DR 大鼠表现出内脏脂肪中脂肪生成的抑制和脂肪酸β-氧化的加速。这些特征可能有助于 DR 大鼠的抗肥胖表型。
