Background The protective effects of magnesium sulfate against ischemia-reperfusion injury of the small intestine in Sprague-Dawley (SD) rats have been confirmed in our previous research. However, its exact mechanis...Background The protective effects of magnesium sulfate against ischemia-reperfusion injury of the small intestine in Sprague-Dawley (SD) rats have been confirmed in our previous research. However, its exact mechanism is unclear. This study was to evaluate the role of PI3K/Akt signal pathway in the protective effect of magnesium sulfate against ischemia-reperfusion injury of the small intestine in SD rats. Methods Rat model of intestinal ischemia-reperfusion injury was used. The SD rats were divided into four groups randomly: sham operation group, ischemia-reperfusion group, magnesium sulfate group and magnesium sulfate plus LY294002 (an inhibitor of PI3K) group. The pathological changes of intestinal mucosa were examined; the activity of diamine oxidase (DAO) in plasma, the plasma contents of malondialdehyde (MDA), and apoptosis rate of the intestinal mucosal cells were determined and compared. The expression of p-Akt was detected by Western blotting. Results There were more evident pathological changes of the intestinal mucosa (higher Chiu's score, P 〈0.05), enhanced DAO activity (P 〈0.05), elevated contents of MDA (P 〈0.05), higher apoptosis rate (P 〈0.05), and lower level of p-Akt (P 〈0.05) in the ischemia-reperfusion group compared with the sham operation group. There were less evident pathological changes of the intestinal mucosa (lower Chiu's score, P 〈0.05), lower DAO activity (P 〈0.05), lower contents of MDA (P 〈0.05), and lower apoptosis rate (P 〈0.05), but higher level of p-Akt (P 〈0.05) irL the magnesium sulfate group compared with the ischemia-reperfusion group. There were more evident pathological changes of the intes,inal mucosa (higher Chiu's score, P 〈0.05), higher contents of MDA (P 〈0.05), higher DAO activity (P 〈0.05) and higher apoptosis rate (P 〈0.05), and lower level of p-Akt (P 〈0.05) in the magnesium sulfate plus LY294002 group compared with the magnesium sulfate group. Conclusions Activation of PI3K/Akt signal pathway results in the reduction of cell apoptosis, which likely accounts for the protective effect of magnesium sulfate against intestinal ischemia-reperfusion injury.展开更多
目的观察HS1相关蛋白X-1(HS1-associated protein X-1,HAX1)对骨肉瘤细胞凋亡的影响。方法应用基因沉默技术在骨肉瘤细胞系MG63中下调HAX1基因的表达,并且通过Western blot实验与免疫荧光实验检测基因沉默效率;应用MTT方法及克隆形成实...目的观察HS1相关蛋白X-1(HS1-associated protein X-1,HAX1)对骨肉瘤细胞凋亡的影响。方法应用基因沉默技术在骨肉瘤细胞系MG63中下调HAX1基因的表达,并且通过Western blot实验与免疫荧光实验检测基因沉默效率;应用MTT方法及克隆形成实验,评价沉默HAX1基因对MG63细胞增殖能力的影响;流式细胞术检测细胞凋亡并通过Western blot实验检测下游蛋白的表达变化。结果沉默HAX1基因抑制人骨肉瘤细胞系MG63的增殖能力与克隆形成能力,流式细胞技术显示沉默HAX1可以诱导MG63细胞凋亡,Western blot实验说明HAX1诱导的MG63细胞凋亡与caspase3和caspase9蛋白上调相关。结论 HAX1可能是维持骨肉瘤细胞增殖能力的关键基因,沉默该基因诱导骨肉瘤细胞凋亡可能与caspase3/caspase9上调相关。展开更多
文摘Background The protective effects of magnesium sulfate against ischemia-reperfusion injury of the small intestine in Sprague-Dawley (SD) rats have been confirmed in our previous research. However, its exact mechanism is unclear. This study was to evaluate the role of PI3K/Akt signal pathway in the protective effect of magnesium sulfate against ischemia-reperfusion injury of the small intestine in SD rats. Methods Rat model of intestinal ischemia-reperfusion injury was used. The SD rats were divided into four groups randomly: sham operation group, ischemia-reperfusion group, magnesium sulfate group and magnesium sulfate plus LY294002 (an inhibitor of PI3K) group. The pathological changes of intestinal mucosa were examined; the activity of diamine oxidase (DAO) in plasma, the plasma contents of malondialdehyde (MDA), and apoptosis rate of the intestinal mucosal cells were determined and compared. The expression of p-Akt was detected by Western blotting. Results There were more evident pathological changes of the intestinal mucosa (higher Chiu's score, P 〈0.05), enhanced DAO activity (P 〈0.05), elevated contents of MDA (P 〈0.05), higher apoptosis rate (P 〈0.05), and lower level of p-Akt (P 〈0.05) in the ischemia-reperfusion group compared with the sham operation group. There were less evident pathological changes of the intestinal mucosa (lower Chiu's score, P 〈0.05), lower DAO activity (P 〈0.05), lower contents of MDA (P 〈0.05), and lower apoptosis rate (P 〈0.05), but higher level of p-Akt (P 〈0.05) irL the magnesium sulfate group compared with the ischemia-reperfusion group. There were more evident pathological changes of the intes,inal mucosa (higher Chiu's score, P 〈0.05), higher contents of MDA (P 〈0.05), higher DAO activity (P 〈0.05) and higher apoptosis rate (P 〈0.05), and lower level of p-Akt (P 〈0.05) in the magnesium sulfate plus LY294002 group compared with the magnesium sulfate group. Conclusions Activation of PI3K/Akt signal pathway results in the reduction of cell apoptosis, which likely accounts for the protective effect of magnesium sulfate against intestinal ischemia-reperfusion injury.