Yakubu F, Lin D, Peters J C, Reed G W, Hill J O
Department of Pediatrics, Vanderbilt University, Nashville, TN, USA.
Obes Res. 1993 Nov;1(6):481-8. doi: 10.1002/j.1550-8528.1993.tb00031.x.
The chronic influence of dietary fat composition on obesity and insulin action is not well understood. We examined the effect of amount (20% vs 60% of total calories) and type (saturated vs polyunsaturated) of fat on insulin action and body composition in mature male rats. Six months of feeding a high fat (HF) diet led to obesity and impaired insulin action (determined by a euglycemic-hyperinsulinemic clamp), neither of which were reversed by a subsequent 6 months of feeding a low fat (LF) diet. Within HF fed rats, type of fat did not affect body composition or insulin action. Six months of feeding a low fat diet led to only a slight decline in insulin action, with no difference due to type of dietary fat. From 6-9 months, insulin action became more impaired in LF rats fed the saturated diet than in LF rats fed the polyunsaturated diet. By 12 months, all groups were obese and had a similar impairment in insulin action. The amount and type of fat in the diet did not influence the overall degree of impairment in insulin action but did affect the time course. Both feeding a high fat diet and feeding a low fat saturated diet accelerated the impairment in insulin action relative to rats fed a low fat polyunsaturated fat diet.
饮食脂肪组成对肥胖和胰岛素作用的长期影响尚未得到充分理解。我们研究了脂肪含量（占总热量的20% vs 60%）和类型（饱和脂肪与多不饱和脂肪）对成年雄性大鼠胰岛素作用和身体组成的影响。六个月的高脂（HF）饮食喂养导致肥胖和胰岛素作用受损（通过正常血糖-高胰岛素钳夹测定），随后六个月的低脂（LF）饮食喂养均未使其逆转。在高脂喂养的大鼠中，脂肪类型不影响身体组成或胰岛素作用。六个月的低脂饮食喂养仅导致胰岛素作用略有下降，饮食脂肪类型对此无差异。从6至9个月，喂食饱和饮食的低脂大鼠比喂食多不饱和饮食的低脂大鼠的胰岛素作用受损更严重。到12个月时，所有组均肥胖且胰岛素作用受损程度相似。饮食中脂肪的含量和类型不影响胰岛素作用受损的总体程度，但会影响时间进程。相对于喂食低脂多不饱和脂肪饮食的大鼠，高脂饮食喂养和低脂饱和饮食喂养均加速了胰岛素作用的受损。
