关键词: <, p>, &alpha, -亚麻酸, 脂类合成, 胰岛素抵抗, 胰岛素诱导基因<, /p>

Abstract: Abstract: Objective We investigate the effect of ALA on lipid biosynthesis-related genes in animal and cell IＲ models． Method HepG2 cells were divided into two groups，normal control group ( NC) and palmitic acid group ( PA) in which cells were firstly cultured for 24 h in the medium contained 0. 25 mmol /L palmitic acid． The glucose uptake，cellular TG and TCH level were determined and once there was significant difference in glucose uptake，ALA took 20 percent the place of PA for another 12 h culture． Celluar TCH and TG level were detected and mＲNA and protein expression of genes related to lipid synthesis were examinated by real-time qPCＲ and Western blot． Ｒesult After incubation with 0. 25 mmol /L PA for 24 h，the glucose uptake of PA group was significantly lowered than NC group indicating the IＲ-HepG2 cell model was established characterized by extremely high TCH level． ALA selectively upregulated the protein expression of INSIG-2 and decreased the TG level in IＲHepG2 cells，and there were no statistically significant differences in TCH level and INSIG-1 protein expression． ALA had no significant effect on the abundance of the transcriptionally active ( 65 kDa) form of Srebp-1c while the Fasn protein reduced by 21% after ALA intervention． When compared with PA，ALA reduced 55 － kDa cleaved form of SＲEBP-2 and Hmgcr protein． Conclusion ALA selectively upregulated the protein expression of INSIG-2 in IＲ-HepG2 cells，rather than Insig-1． ALA reduced the abundance of post-translational form of SＲEBP-2 and its target Hmgcr and Fasn by increasing the expression of INSIG-2．

Key words: <p>Alpha-Linolenic acid, lipids synthesis, insulin resistance, insulin induced genes</p>