Shiraev T, Chen H, Morris M J
Department of Pharmacology, School of Medical Sciences, University of New South Wales, Sydney, NSW, Australia.
J Neuroendocrinol. 2009 Jul;21(7):602-9. doi: 10.1111/j.1365-2826.2009.01877.x. Epub 2009 Apr 13.
The rapid rise in obesity has been linked to altered food consumption patterns. There is increasing evidence that, in addition to total energy intake, the macronutrient composition of the diet may influence the development of obesity. The present study aimed to examine the impact of high dietary fat content, under both isocaloric and hypercaloric conditions, compared with a low fat diet, on adiposity, glucose and lipid metabolism, and brain appetite regulators in rats. Male Sprague-Dawley rats were exposed to one of three diets: control (14% fat), ad lib high-fat palatable (HFD, 35% fat) or high-fat palatable restricted (HFD-R, matched to the energy intake of control) and were killed in the fasting state 11 weeks later. Body weight was increased by 28% in unrestricted HFD fed rats, with an almost tripling of caloric intake and fat mass (P < 0.001) and double the plasma triglycerides of controls. Glucose intolerance and increased insulin levels were observed. HFD-R animals calorie matched to control had double their fat mass, plasma insulin and triglycerides (P < 0.05). Only ad lib consumption of the HFD increased the hypothalamic mRNA expression of the appetite-regulating peptides, neuropeptide Y and pro-opiomelanocortin. Although restricted consumption of palatable HFD had no significant impact on hypothalamic appetite regulators or body weight, it increased adiposity and circulating triglycerides, suggesting that the proportion of dietary fat, independent of caloric intake, affects fat deposition and the metabolic profile.
肥胖率的迅速上升与食物消费模式的改变有关。越来越多的证据表明，除了总能量摄入外，饮食中的宏量营养素组成可能会影响肥胖的发展。本研究旨在考察在等热量和高热量条件下，与低脂饮食相比，高膳食脂肪含量对大鼠肥胖、葡萄糖和脂质代谢以及脑内食欲调节因子的影响。将雄性斯普拉格-道利大鼠分为三组，分别给予三种饮食之一：对照组（14%脂肪）、随意进食高脂可口饮食（HFD，35%脂肪）或高脂可口限制饮食（HFD-R，能量摄入与对照组匹配），11周后在禁食状态下处死。随意进食HFD的大鼠体重增加了28%，热量摄入和脂肪量几乎增加了两倍（P<0.001），血浆甘油三酯是对照组的两倍。观察到葡萄糖耐量降低和胰岛素水平升高。热量摄入与对照组匹配的HFD-R动物脂肪量、血浆胰岛素和甘油三酯增加了一倍（P<0.05）。只有随意进食HFD会增加食欲调节肽神经肽Y和阿黑皮素原在下丘脑的mRNA表达。尽管限制食用可口的HFD对下丘脑食欲调节因子或体重没有显著影响，但它增加了肥胖和循环甘油三酯，这表明膳食脂肪比例独立于热量摄入，会影响脂肪沉积和代谢状况。
