Lignans from Patrinia scabiosaefolia improve insulin resistance by activating PI-3K/AKT pathway and promoting GLUT4 expression
Zhenhua Liu, Mengke Wang, Lijun Meng, Yixiao Chen, Qiuyi Wang, Yan Zhang, Xuefeng Xi, Wenyi Kang
Abstract
Patrinia scabiosaefolia, is used as wild vegetable in China for more than 2 000 years, with a variety of pharmacological activities, including anti-inflammatory, anti-tumor and hypoglycemic. Based on our ongoing research on chemical constituents and hypoglycemic activity of P. scabiosaefolia, 4 lignan compounds, (+)-isolariciresinol (1), 7R,7'R,8S,8'S-(+)-neo-olivil-4-O-β-D-glucopyranoside (2), 4-O-methylcedrusin (3) and patrinian A (4), were isolated and identified. The hypoglycemic activity showed that compounds 2 and 3 could extremely significantly improve insulin resistance at 100 (P < 0.001), 50 (P < 0.001) and 25 µmol/L (P < 0.01) in IR 3T3-L1 cells. While compound 4 only promoted glucose uptake by IR 3T3-L1 cells at 100 µmol/L (P < 0.01). Western blotting experiments showed that compounds 2 and 4 up-regulated the protein expressions of p-IRS, PI-3K, p-AKT and glucose transporter 4 (GLUT4), and promoted the transcription of GLUT4 mRNA. Therefore, the mechanisms of compounds 2 and 4 were presumed to improve IR by activating PI-3K/AKT signaling pathway.