枯否细胞在高脂诱导的肝脏胰岛素抵抗中的作用

【摘要】目的探讨枯否细胞在高脂诱导的肝脏胰岛素抵抗中的作用。方法将C57BL/6J小鼠84只，分为普食组和高脂组，其中1组普食和1组高脂小鼠在喂养后1、2、4、8、12、16周行葡萄糖耐量检测，另外6组普食和6组高脂小鼠分别在上述时间处死取肝脏；Western blot检测肝脏胰岛素受体底物1（IRS1）-ser307、蛋白激酶B（Akt）-ser473、核糖体蛋白S6激酶1（S6K1）-thr389、磷酸化c-Jun氨基末端激酶（p-JNK）表达；实时定量PCR检测肝脏炎性因子单核细胞趋化蛋白（MCP）-1、肿瘤坏死因子（TNF）-α、白细胞介素（IL）-1β、IL-10mRNA的表达。结果与普食喂养相比，高脂喂养小鼠1周后葡萄糖耐量检测显示葡萄糖代谢异常（P<0.05），Western blot显示高脂组肝脏IRS1-ser307、S6K1-thr389（第4~16周）、p-JNK（2~16周）表达增强，Akt-ser473（8~16周）表达减弱，蛋白相对表达量与之一致（均P<0.05）。第2~16周高脂组肝脏炎性因子MCP-1、TNF-α、IL-1βmRNA表达高于普食组（均P<0.01），抗炎因子IL-10mRNA在第4~16周时低于普食组（均P<0.01）。结论高脂饮食可能通过调节M1型枯否氏细胞分泌炎性因子和抑制M2型枯否细胞分泌抗炎因子在肝脏胰岛素抵抗中发挥作用。

Role of Kupffer Cells in High Fat Diet Induced Hepatic Insulin Resistance

[Abstract]ObjectiveTo explore the role of Kupffer cells in high fat diet induced hepatic insulin resistance. Methods Eighty-four C57BL/6J mice were divided into two groups: normal chow (NC) group (7subgroups) and high fat diet(HFD) group (7subgroups). Glucose tolerance tests were performed at feeding time of1，2，4，8 ,12and16weeks in one NC group and one HFD group. The mice livers at the same feeding time were obtained in other 6NC groups and 6HFD groups respectively. The expression levels of IRS1-ser307, Akt-ser473, S6K1-thr389and p-JNK were detected by Western blot as-say. The values of MCP-1，TNF-α，IL-1βand IL-10mRNA were examined by qRT-PCR. Results Compared with NC group, the impaired glucose tolerance was found from the first week in HFD group (P<0.05). The hepatic expressions of IRS1-ser307, S6K1-thr389(4-16weeks ) and p-JNK(2-16weeks ) increased and Akt-ser473（8-16 weeks）decreased in HFD group than those of NC group. The same results were gained by analysis of protein relative expression (allP<0.05). The hepatic pro-inflammatory factor MCP-1,TNF-αand IL-1βmRNA expressions were higher in HFD group than those in NC group during2-16weeks (allP<0.01). The anti- inflammatory factor IL-10mRNA was significantly lower in HFD group than that in NC group during4-16weeks (allP<0.01). Conclusion High fat diet maybe play a role in the hepatic insulin resistance by stimulating M1Kupffer cells to secrete pro-inflammatory factor and inhibiting M2Kupffer cells to secrete anti-inflammatory factor.