College of Pharmacy, Chungnam National University, Daejeon, Republic of Korea.
J Med Food. 2010 Dec;13(6):1331-9. doi: 10.1089/jmf.2010.1155.
The aim of the present study was to investigate effects of the ethyl acetate fraction of an ethanol extract of Coix lachryma-jobi (ECLJ) on glucose uptake and adipocyte differentiation in 3T3-L1 cells. ECLJ phosphorylated AMP-activated protein kinase (AMPK) and its downstream substrate acetyl-coenzymeA carboxylase in 3T3-L1 cells in a time- and dose-dependent manner. Moreover, we discovered that compound C inhibits ECLJ-stimulated ACC phosphorylation. In addition, ECLJ exhibited a dose-dependent stimulation of glucose uptake in 3T3-L1 cells, and this increase was obviously attenuated by compound C. ECLJ also caused a decrease in the expression levels of adipogenesis factors such as fatty acid synthase, sterol-regulatory-element-binding protein-1c, peroxisome proliferator-activated receptor γ, and CAATT/enhancer binding protein α in a dose-dependent manner. Differentiation was examined by Oil red O staining activity after ECLJ treatment for 6 days. ECLJ decreased mean droplet size. These results suggest a possible role for AMPK in the process of adipose differentiation and that ECLJ targeted for adipocyte functions could be effective in improving the symptoms of metabolic syndrome.
本研究旨在探讨薏苡仁乙醇提取物乙酸乙酯部位（ECLJ）对 3T3-L1 细胞葡萄糖摄取和脂肪细胞分化的影响。ECLJ 可时间和剂量依赖性地使 3T3-L1 细胞中 AMP 激活的蛋白激酶（AMPK）及其下游底物乙酰辅酶 A 羧化酶磷酸化。此外，我们发现化合物 C 可抑制 ECLJ 刺激的 ACC 磷酸化。此外，ECLJ 呈剂量依赖性刺激 3T3-L1 细胞葡萄糖摄取，该增加可被化合物 C 明显减弱。ECLJ 还可剂量依赖性地下调脂肪酸合酶、固醇调节元件结合蛋白-1c、过氧化物酶体增殖物激活受体 γ 和 CAATT/增强子结合蛋白 α 等脂肪生成因子的表达水平。用 ECLJ 处理 6 天后，通过油红 O 染色活性来检测分化。ECLJ 减小了平均液滴大小。这些结果提示 AMPK 可能在脂肪分化过程中起作用，靶向脂肪细胞功能的 ECLJ 可能有效改善代谢综合征的症状。
