松花粉提取物对胰岛素抵抗HepG2细胞糖脂代谢的影响

Effects of pine pollen extracts on insulin resisted glycolipid metabolism in HepG2 cells

研究松花粉提取物对胰岛素抵抗Hep G2细胞糖脂代谢的影响,探究其潜在分子机制。采用游离脂肪酸构建Hep G2细胞胰岛素抵抗模型,经油红O染色确认模型成功后,采用MTT法研究不同极性的松花粉提取物对细胞增殖的影响。测定各组上清葡萄糖,胞内糖原,上清甘油三酯(TG),胞内TG以及胞内总胆固醇(TC)的含量,实时荧光PCR定量检测细胞裂解液中的调控糖脂代谢关键基因In SR、PI3K以及GLUT-4的mRNA表达水平。结果表明,不同极性的松花粉提取物在质量浓度为100～500μg/m L时,对细胞无明显毒性;不同极性的松花粉提取物能够促进细胞吸收葡萄糖,抑制糖原降解,抑制TG和TC的形成,促进TG向细胞外转运,从而改善Hep G2胰岛素抵抗状况。各松花粉处理组细胞PI3K以及GLUT-4 mRNA表达量均上调,说明松花粉能够激活PI3K/Akt/GLUT-4通路从而促进糖代谢;乙酸乙酯相(AE),正丁醇相(BU)和水相(WT)组细胞In SR mRNA表达量显著上调,说明这3种提取物能够通过提高胰岛素的敏感性改善胰岛素抵抗。

This study aimed to evaluate the effects of pine pollen extracts on glycolipid metabolism in insulin-resistant HepG2 cells,and explore its underlying molecular mechanisms. The insulin-resistant HepG2 cell model was established by free fatty acids and validated using Oil red O staining. MTT assay was used to study the effects of pine pollen extracts with different polarities on cell proliferation. Levels of glucose,glycogen,and triglycerides( TG) in cell supernatants were measured. TG and total cholesterol( TC) in cytoplasm were also determined. Quantitative realtime PCR( qRT-PCR) was used to detect the mRNA expression levels of glucose and lipid metabolism-related genes in cell lysis buffer,such as InSR,PI3 K and GLUT-4. The results showed that there were no obvious toxic effects of pine pollen extracts on HepG2 cells at 100-500 μg/m L. The absorption of glucose and transhipment of TG were promoted,and the degradation of glycogen and formations of TG and TC were suppressed after pine pollen extracts treatment,indicating that the insulin-resistance of HepG2 was improved. Meanwhile,the mRNA expressions of PI3 K and GLUT-4 significantly increased in all pine pollen extracts treatment groups,which means that pine pollen could promote glucose metabolism by activating the PI3 K/Akt/GLUT-4 pathway. It was also found that pine pollen after ethyl acetate,butanol and water treatments could attenuate insulin resistance through enhancing insulin sensitivity,because the mRNA expression of InSR up-regulated significantly among these three groups.