Zhang Xianan, Lv Qiang, Jia Sheng, Chen Yanhong, Sun Chongde, Li Xian, Chen Kunsong
Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology, Zhejiang University, Zijingang Campus, Hangzhou, 310058, PR China.
Laboratory Animal Centre of Zhejiang University, Hangzhou, 310058, China.
Food Funct. 2016 Jul 13;7(7):3130-40. doi: 10.1039/c6fo00397d.
In the present study, male diabetic KK-A(y) mice were used to investigate the antidiabetic effect of bayberry fruit extract (BFE, 200 mg kg(-1)) by gavage for 5 weeks. BFE significantly lowered fasting blood glucose, improved glucose tolerance and insulin sensitivity in KK-A(y) mice. It significantly reduced serum concentrations of glucose, lipids, inflammation, and liver function markers, including insulin, glucagon, leptin, total cholesterol, triglycerides, low density lipoprotein, interleukin-1β, and alanine transferase in KK-A(y) mice. Liver weight and liver lipid accumulation were also markedly reduced by BFE in mice. The hypoglycemic effect of BFE appeared to be partially mediated through the inhibition of hepatic gluconeogenesis, which was supported by the reduced PPARγ coactivator 1-alpha (PGC-1α) and phosphoenolpyruvate carboxykinase (PEPCK) mRNA expressions in the liver of KK-A(y) mice and by the decreased glucose production, increased glycolysis as well as the reduced gene expression levels of PGC-1α, PEPCK, and glucose-6-phosphatase (G6Pase) in HepG2 cells. Gene expressions of hepatic lipid metabolism and inflammatory markers were also down-regulated by BFE in the liver of KK-A(y) mice. Furthermore, BFE promoted hepatic phosphorylation of AMPKα (Thr172) both in vivo and in vitro. Therefore, the activation of the AMPK pathway may play an important role in the antidiabetic effects of BFE, and red Chinese bayberry fruits may be an effective dietary food for the management of type 2 diabetes and its complications.
在本研究中，雄性糖尿病KK-A(y)小鼠被用于通过灌胃给予杨梅果实提取物（BFE，200 mg kg(-1)）5周，以研究其抗糖尿病作用。BFE显著降低了KK-A(y)小鼠的空腹血糖，改善了葡萄糖耐量和胰岛素敏感性。它显著降低了KK-A(y)小鼠血清中的葡萄糖、脂质、炎症和肝功能标志物浓度，包括胰岛素、胰高血糖素、瘦素、总胆固醇、甘油三酯、低密度脂蛋白、白细胞介素-1β和丙氨酸转氨酶。BFE还显著降低了小鼠的肝脏重量和肝脏脂质积累。BFE的降血糖作用似乎部分是通过抑制肝糖异生介导的，这得到了KK-A(y)小鼠肝脏中PPARγ共激活因子1-α（PGC-1α）和磷酸烯醇丙酮酸羧激酶（PEPCK）mRNA表达降低以及葡萄糖生成减少、糖酵解增加以及HepG2细胞中PGC-1α、PEPCK和葡萄糖-6-磷酸酶（G6Pase）基因表达水平降低的支持。BFE还下调了KK-A(y)小鼠肝脏中肝脂质代谢和炎症标志物的基因表达。此外，BFE在体内和体外均促进了AMPKα（Thr172）的肝脏磷酸化。因此，AMPK途径的激活可能在BFE的抗糖尿病作用中起重要作用，杨梅果实可能是用于管理2型糖尿病及其并发症的有效膳食食品。
