INRA, UMR 1019 Nutrition Humaine, Saint Genès Champanelle, France.
Nutrition. 2012 May;28(5):566-71. doi: 10.1016/j.nut.2011.08.020. Epub 2011 Dec 20.
Energy restriction decreases fat mass and fat-free mass. Our aim was to prevent the latter using type and timing of protein nutrition as tools.
Young male Wistar rats were given a high-energy diet for 5 wk and then energy restricted and fed a high-protein diet containing caseins, milk-soluble proteins (MSP), or a casein-MSP mixture (n = 9 per group) as the only source of protein for 3 wk. Food intake was spread over 12 h, whereas in a previous experiment rats consumed their daily ration within 2 to 3 h. Weight and food intake were recorded. The body composition was measured by dual-energy x-ray absorptiometry before and after energy restriction. After 3 wk, the hind-limb muscles, the kidney, intestine, liver, and spleen weights, metabolic plasma parameters, and the liver and extensor digitorum longus muscle protein synthesis rates were measured in the postprandial state.
The food intake was similar in all groups. Energy restriction induced a significant decrease in body weight and fat mass (P < 0.001) and stopped the slow growth of lean body mass, with no differences between groups. Among all tissues, a significant effect was detected only for the intestine (P = 0.0012), with a higher weight in the casein group. Postprandial liver and muscle protein synthesis rates were not different between groups.
When using a high-protein diet spread over 12 h, the nature of the protein intake has no influence on the sparing of lean body mass during energy restriction in young overweight rats.
能量限制会减少脂肪量和去脂体重。我们的目的是使用蛋白质营养的类型和时间作为工具来防止后者。
给予年轻雄性 Wistar 大鼠高热量饮食 5 周，然后进行能量限制并给予含有酪蛋白、乳清蛋白（MSP）或酪蛋白-MSP 混合物的高蛋白饮食作为唯一蛋白质来源，持续 3 周。食物摄入量在 12 小时内分布，而在之前的实验中，大鼠在 2 到 3 小时内消耗其每日摄入量。在能量限制前后通过双能 X 射线吸收法测量体重和食物摄入量。3 周后，在餐后状态下测量后肢肌肉、肾脏、肠道、肝脏和脾脏重量、代谢血浆参数以及肝脏和伸趾长肌的蛋白质合成率。
所有组的食物摄入量相似。能量限制导致体重和脂肪量显著下降（P < 0.001），并停止了瘦体重的缓慢增长，各组之间没有差异。在所有组织中，只有肠道（P = 0.0012）出现显著影响，酪蛋白组的重量更高。各组之间的餐后肝和肌肉蛋白质合成率没有差异。
当使用 12 小时内分布的高蛋白饮食时，在超重年轻大鼠进行能量限制期间，蛋白质摄入的性质对瘦体重的保存没有影响。
