Department of Pathology, Texas Tech University Health Sciences Center, Lubbock, TX 79430-8115, USA.
Nutr Res. 2012 Jun;32(6):448-57. doi: 10.1016/j.nutres.2012.05.001. Epub 2012 Jun 8.
This study investigates the effects of green tea polyphenols (GTPs) on body composition and bone properties along with mechanisms in obese female rats. Thirty-six 3-month-old Sprague Dawley female rats were fed either a low-fat (LF) or a high-fat (HF) diet for 4 months. Animals in the LF diet group continued on an LF diet for additional 4 months, whereas those in the HF diet group were divided into 2 groups: with GTP (0.5%) or without in drinking water, in addition to an HF diet for another 4 months. Body composition, femur bone mass and strength, serum endocrine and proinflammatory cytokines, and liver glutathione peroxidase (GPX) protein expression were determined. We hypothesized that supplementation of GTP in drinking water would benefit body composition, enhance bone quality, and suppress obesity-related endocrines in HF diet-induced obese female rats and that such changes are related to an elevation of antioxidant capacity and a reduction of proinflammatory cytokine production. After 8 months, compared with the LF diet, the HF diet increased percentage of fat mass and serum insulin-like growth factor I and leptin levels; reduced percentage of fat-free mass, bone strength, and GPX protein expression; but had no effect on bone mineral density and serum adiponectin levels in the rats. Green tea polyphenol supplementation increased percentage of fat-free mass, bone mineral density and strength, and GPX protein expression and decreased percentage of fat mass, serum insulin-like growth factor I, leptin, adiponectin, and proinflammatory cytokines in the obese rats. This study shows that GTP supplementation benefited body composition and bone properties in obese rats possibly through enhancing antioxidant capacity and suppressing inflammation.
本研究旨在探讨绿茶多酚（GTP）对肥胖雌性大鼠体成分和骨特性的影响及其作用机制。36 只 3 月龄 Sprague Dawley 雌性大鼠分别给予低脂（LF）或高脂（HF）饮食喂养 4 个月。LF 饮食组继续给予 LF 饮食喂养 4 个月，而 HF 饮食组则分为 2 组：继续给予 HF 饮食并在饮水中添加或不添加 GTP（0.5%），再喂养 4 个月。检测体成分、股骨骨量和强度、血清内分泌和促炎细胞因子以及肝脏谷胱甘肽过氧化物酶（GPX）蛋白表达。我们假设，在 HF 饮食诱导的肥胖雌性大鼠中，饮水中添加 GTP 将有益于体成分，增强骨质量，并抑制与肥胖相关的内分泌，且这些变化与抗氧化能力的提高和促炎细胞因子产生的减少有关。8 个月后，与 LF 饮食相比，HF 饮食增加了脂肪质量百分比和血清胰岛素样生长因子 I 和瘦素水平；降低了去脂体质量百分比、骨强度和 GPX 蛋白表达；但对骨密度和血清脂联素水平没有影响。绿茶多酚补充剂增加了去脂体质量百分比、骨密度和强度，以及 GPX 蛋白表达，降低了脂肪质量百分比、血清胰岛素样生长因子 I、瘦素、脂联素和促炎细胞因子水平。本研究表明，GTP 补充有益于肥胖大鼠的体成分和骨特性，可能是通过增强抗氧化能力和抑制炎症。
