BMK1和ROS在慢性饮酒大鼠胃黏膜细胞增殖中作用的研究

Effect of ROS and BMK1 on the gastric mucosal cell proliferation in the chronic alcohol drinking rats

目的:研究慢性饮酒引起大鼠胃黏膜细胞增殖的增加是否与ROS及ERK1/2和/或BMK1有关。方法:SD大鼠随机分4组:对照组;饮用6%酒精组;100mg/kg槲皮素灌胃组;饮酒加槲皮素灌胃组,均处理7天。用免疫印迹技术检测胃黏膜组织中增殖细胞核抗原(PCNA)、细胞周期蛋白D1(CyclinD1)、细胞外信号调节蛋白激酶(ERK1/2)和大分子MAPK(BMK1)的表达及活性;采用免疫荧光双重染色方法对胃黏膜组织石蜡切片PCNA和磷酸化的BMK1(p-BMK1)蛋白进行定位检测。结果:慢性饮酒组胃黏膜PCNA和CyclinD1表达上调;酒精组PCNA、p-BMK1双阳性细胞主要定位于胃底腺颈部;BMK1的表达、激活与酒精诱导的胃黏膜干细胞增殖呈正相关,ERK1/2的表达、激活与增殖无关;但饮酒加槲皮素灌胃阻止了慢性饮酒所致胃黏膜细胞增殖,而且抑制了酒精诱导的BMK1表达与激活。结论:慢性饮酒刺激胃黏膜底腺干细胞的增殖可能与酒精引起活性氧(ROS)增多有关,同时本研究还第1次发现慢性饮酒诱导胃底腺干细胞增殖是由BMK1所介导。

Objective： To investigate the correlation between the gastric mucosal cell proliferation and low-concentration alcohol intake in a chronic drinking rat model, and to investigate the possible role of ROS/BMK! pathway in this process. Methods： SD rats were randomly divided into 4 groups： control group, administered with tap water; ethanol group, administered with 6% ethanol in the drinking water; quercetin group, administered with quereetin （100 mg/kg） by intragastrie garage twice a day; ethanol＋quercetin group, administered with quercetin combined With 6% ethanol. The cell proliferation in gastric mucosa of rats was analyzed by the expression of PCNA and CyclinD1 using immunoblotting method. Activation of ERK and BMK1 was evaluated by the expression and phosphorylation of these kinases using western blot analysis. Results ： Compared to the controls, the cell proliferation in gastric mucosa of rats exposured to the ethanol was enhanced for 7 days, and the activation of BMK1 was also increased in this period. Otherwise quercetin, as a free radical scavenger, attenuated increased cell proliferation and activation of BMK1 in rat stomach treated with ethanol. However, no changes of ERKs expression and phosphorylation occurred in the rats in all groups. Conclusion： Our results suggest that long-term stimulus with the low-concentration ethanol-induced gastric mucosal cell proliferation is related with BMK1 signaling pathway via ROS production.