Department of Food and Nutrition, Hoseo University, 165 Sechul-Ri, BaeBang-Yup, Asan-Si, ChungNam-Do, South Korea.
Eur J Nutr. 2011 Mar;50(2):107-18. doi: 10.1007/s00394-010-0120-0. Epub 2010 Jun 26.
Insulin resistance is a common symptom of metabolic diseases such as obesity, type 2 diabetes and hyperlipidemia.
We investigated whether Gastrodia elata Blume water extract(GEB), containing phenolic compounds, had a beneficial action on insulin resistance in male Sprague-Dawley rats fed a high fat diet(HFD) and determined how this effect was produced. In addition, the bioactive candidates involved were identified.
Rats fed HFD were daily administered with 0.3 g GEB(GEB-L), 1 g GEB(GEB-H), or 1 g cellulose(control) per kg body weight for 8 weeks, while rats in the fourth group were fed a low fat diet(LFD). In vitro study, 4 major components of GEB were tested for their impact on fat accumulation.
Rats in the control group exhibited a higher weight gain of epididymal and retroperitoneal fat pads than those fed LFD, while GEB prevented such an increment in a dose-dependent manner. GEB-H significantly decreased energy intake partly through potentiating STAT3 phosphorylation and attenuating AMPK phosphorylation in the hypothalamus. GEB-H also increased energy expenditure with the increase in fat oxidation. GEB-H increased whole body glucose disposal rates and decreased hepatic glucose output compared to the control. Among the major components of GEB, 4-hydroxybenzaldehyde and vanillin decreased triglyceride accumulation by modulating the expression of genes involved in fat metabolism in 3T3-L1 adipocytes. They increased insulin-stimulated glucose uptake to reduce insulin resistance.
GEB-H, mainly as a result of the action of 4-hydroxybenzaldehyde and vanillin, reduces insulin resistance by decreasing fat accumulation in adipocytes by activating fat oxidation and potentiating leptin signaling in diet-induced obese rats.
胰岛素抵抗是肥胖症、2 型糖尿病和高脂血症等代谢疾病的常见症状。
我们研究了天麻水提取物（GEB）是否含有酚类化合物，对高脂肪饮食（HFD）喂养的雄性 Sprague-Dawley 大鼠的胰岛素抵抗有有益作用，并确定了这种作用是如何产生的。此外，还确定了涉及的生物活性候选物。
用 HFD 喂养的大鼠每天给予 0.3 g GEB（GEB-L）、1 g GEB（GEB-H）或 1 g 纤维素（对照）/kg 体重，持续 8 周，而第四组大鼠则喂食低脂饮食（LFD）。在体外研究中，测试了 GEB 的 4 种主要成分对脂肪积累的影响。
与喂食 LFD 的大鼠相比，对照组大鼠附睾和腹膜后脂肪垫的体重增加更高，而 GEB 以剂量依赖性方式阻止了这种增加。GEB-H 通过增强下丘脑 STAT3 磷酸化和减弱 AMPK 磷酸化，部分降低了能量摄入。GEB-H 还通过增加脂肪氧化来增加能量消耗。与对照组相比，GEB-H 增加了全身葡萄糖处置率并降低了肝葡萄糖输出。在 GEB 的主要成分中，4-羟基苯甲醛和香草醛通过调节脂肪代谢相关基因的表达来减少脂肪细胞中的甘油三酯积累，从而增加胰岛素刺激的葡萄糖摄取，降低胰岛素抵抗。
GEB-H 主要通过 4-羟基苯甲醛和香草醛的作用，通过激活脂肪氧化和增强肥胖大鼠瘦素信号来减少脂肪细胞中脂肪积累，从而降低胰岛素抵抗。
