Goseki-Sone Masae, Maruyama Rieko, Sogabe Natsuko, Hosoi Takayuki
Division of Nutrition, Department of Food and Nutrition, Japan Women's University, 2-8-1 Mejirodai, Bunkyo-ku, Tokyo 112-8681, Japan.
Obesity (Silver Spring). 2007 Nov;15(11):2605-13. doi: 10.1038/oby.2007.312.
In this study, we examined the effects of lactose on long-term high-fat-diet-induced obesity in rats.
A total of 112 Sprague-Dawley strain female rats (6 weeks old) were divided into four groups: a basic control diet group (Cont), 10% lactose diet group (Lac), high-fat diet group (Fat), and high-fat with 10% lactose diet group (Fat+Lac). After 0, 7, 14, and 84 days from starting the experimental diet, the animals were fasted overnight and killed by bleeding from the abdominal aorta under anesthesia (n = 8 or 9/group).
After 84 days, the addition of lactose to the high-fat diet decreased the final body weight, body weight gain, fat accumulation, and the levels of serum leptin, serum triglycerides, and serum glucose significantly (p < 0.05). Although there was no significant difference in the levels of serum calcium and phosphorus between the Fat and Fat+Lac groups, lumbar vertebral bone mineral density was significantly higher in the Fat+Lac group than in the Cont group on Day 82. Interestingly, the level of serum 1alpha, 25-dihydroxyvitamin D(3) in the Fat+Lac group on Day 84 was reduced by 74% compared with the Fat group (p < 0.01), while there was no significant difference in serum parathyroid hormone levels between the Fat and Fat+Lac groups.
This is the first study to suggest that the addition of lactose to a long-term high-fat diet may regulate not only calcium metabolism but also fat deposition. Further studies on the mechanism of dietary lactose in the regulation of adiposity would provide valuable data for the prevention of long-term high-fat-diet-induced obesity.
在本研究中，我们检测了乳糖对长期高脂饮食诱导的大鼠肥胖的影响。
总共112只6周龄的斯普拉格-道利雌性大鼠被分为四组：基础对照饮食组（Cont）、10%乳糖饮食组（Lac）、高脂饮食组（Fat）和含10%乳糖的高脂饮食组（Fat+Lac）。从开始实验饮食起0、7、14和84天后，动物禁食过夜，在麻醉下通过腹主动脉放血处死（每组n = 8或9）。
84天后，在高脂饮食中添加乳糖显著降低了最终体重、体重增加、脂肪堆积以及血清瘦素、血清甘油三酯和血清葡萄糖水平（p < 0.05）。虽然Fat组和Fat+Lac组之间血清钙和磷水平无显著差异，但在第82天，Fat+Lac组的腰椎骨矿物质密度显著高于Cont组。有趣的是，与Fat组相比，Fat+Lac组在第84天的血清1α,25-二羟基维生素D(3)水平降低了74%（p < 0.01），而Fat组和Fat+Lac组之间血清甲状旁腺激素水平无显著差异。
这是第一项表明在长期高脂饮食中添加乳糖不仅可能调节钙代谢，还可能调节脂肪沉积的研究。对膳食乳糖调节肥胖机制的进一步研究将为预防长期高脂饮食诱导的肥胖提供有价值的数据。
