论文部分内容阅读
目的:探讨睾酮(T)在肝脏胰岛素抵抗(IR)形成过程中的作用及其分子途径。方法:将成年C57BL/6雌鼠随机分为T组(n=11)及对照组(n=10),T组小鼠每日腹腔注射T(10μg/g体质量,溶剂为蓖麻油),对照组每日腹腔注射相同体积的蓖麻油,连续给药24周后处死,分离出原代小鼠肝细胞进行体外培养,用胰岛素(Ins)处理细胞后,通过液闪法检测原代肝细胞中的糖原合成率。分别用10~(-5) mol/L和10~(-7) mol/L浓度的T溶液短时间(1 h)或长时间(36 h)处理体外培养的人肝癌细胞系BEL-7404后,再用Ins处理BEL-7404细胞,然后通过液闪法检测细胞中的糖原合成率;并通过免疫印迹法检测细胞中Akt、GSK3β蛋白的表达水平和磷酸化水平。结果:Ins对T组小鼠原代肝细胞中糖原合成的诱导作用显著低于对照组(P<0.05),提示T组小鼠原代肝细胞对Ins的敏感性降低。BEL-7404细胞经T短时间(1 h)处理后,Ins对细胞中糖原合成率以及Akt和GSK3β蛋白活性的诱导作用显著提高(P<0.05);但当BEL-7404细胞经高浓度T(10~(-5) mol/L)长时间(36 h)处理后,Ins对细胞中糖原合成率以及Akt和GSK3β蛋白活性的诱导作用显著降低(P<0.05),提示高浓度T在短时间内能增强BEL-7404细胞对Ins的敏感性,但长时间暴露后会降低细胞对Ins的敏感性。结论:长时间的T暴露可能会降低肝细胞中Ins信号转导活性,从而干扰肝细胞对Ins的敏感性,导致IR的产生。
Objective: To explore the role of testosterone (T) in hepatic insulin resistance (IR) and its molecular pathways. Methods: Adult C57BL / 6 female mice were randomly divided into T group (n = 11) and control group (n = 10). T mice were injected intraperitoneally with T (10μg / g body weight and castor oil as solvent) The control group was intraperitoneally injected with the same volume of castor oil daily for 24 weeks and then sacrificed. Primary mouse hepatocytes were isolated and cultured in vitro. After treated with insulin, the primary hepatocytes In the glycogen synthesis rate. The human hepatoma cell line BEL-7404 cultured in vitro was treated with 10-5 mol / L and 10-7 mol / L T solution for a short time (1 h) or for a long time (36 h) , Followed by treatment of BEL-7404 cells with Ins. Then the rate of glycogen synthesis in the cells was detected by liquid scintillation. The expression and phosphorylation of Akt and GSK3β in cells were detected by Western blotting. Results: The effect of Ins on Induction of glycogen synthesis in primary hepatocytes of T group was significantly lower than that of the control group (P <0.05), suggesting that the sensitivity of primary hepatocytes of T group to Ins decreased. The induction of glycogen synthesis and the activity of Akt and GSK3β in BEL-7404 cells treated with T for a short time (1 h) were significantly increased (P <0.05). However, when BEL-7404 cells were treated with high concentration of T (10 ~ (-5) mol / L) for 36 h, the effect of Ins on the synthesis rate of glycogen and the activity of Akt and GSK3β were significantly decreased (P <0.05), suggesting that high concentration of T at A short time can enhance the sensitivity of BEL-7404 cells to Ins, but prolonged exposure will reduce the sensitivity of cells to Ins. CONCLUSION: Prolonged T exposure may reduce Ins signaling activity in hepatocytes and interfere with the sensitivity of hepatocytes to Ins, resulting in IR.