Objective To investigate effect of pinacidil, an ATP sensitive potassium channel （KATP） opener, on the neuronal apoptosis and its signaling transduction mechanism following focal cerebral ischemia-reperfusion in rat...Objective To investigate effect of pinacidil, an ATP sensitive potassium channel （KATP） opener, on the neuronal apoptosis and its signaling transduction mechanism following focal cerebral ischemia-reperfusion in rats. Methods One hundred male Wistar rats were randomly divided into four groups： A, sham-operated group; B, ischemia-reperfusion group; C, KATe opener treatment group; and D, KATe opener and blocker treatment group. The middle cerebral artery occlusion （MCAO） model was established by using the intraluminal suture occlusion method, neuronal apoptosis was determined by TUNEL staining, and expressions of caspase-8, caspase-9 and caspase-3 mRNA were detected by in situ hybridization. Results （1） The numbers of apoptotic neurons at 12 h, 24 h, 48 h, and 72 h were significantly less in group C than in groups B and D （P 〈 0.01 or P 〈 0.05）; and there was no difference between groups B and D at all time points （P 〉 0.05）. （2） The expressions of caspase-3 mRNA and caspase-8 mRNA at all times and the expressions of caspase-9 mRNA at 12 h, 24 h, 48 h, 72 h were significantly lower in group C than in groups B and D （P 〈 0.01 or P 〈 0.05）; and there were no differences between groups B and D at all time points （P 〉 0.05）. Conclusions KATP opener can significantly decrease the neuronal apoptosis and the expressions of caspase-3, caspase-8 and caspase-9 mRNAs following cerebral ischemiareperfusion. The neuronal apoptosis may be decreased by the inhibition of both mitochondrial and death-receptor signal pathways.展开更多
背景:程序性细胞死亡受体1(programmed death receptor-1,PD-1)在高糖环境下影响骨髓间充质干细胞成骨分化的作用机制尚不清楚。目的:探讨高糖环境中PD-1对大鼠骨髓间充质干细胞成骨分化的影响及其调控机制。方法:将大鼠骨髓间充质干细...背景:程序性细胞死亡受体1(programmed death receptor-1,PD-1)在高糖环境下影响骨髓间充质干细胞成骨分化的作用机制尚不清楚。目的:探讨高糖环境中PD-1对大鼠骨髓间充质干细胞成骨分化的影响及其调控机制。方法:将大鼠骨髓间充质干细胞随机分为正常糖组(5.6 mmol/L)、高糖组(30 mmol/L)、PD-1过表达组、PD-1过表达空载组、PD-1敲低组、PD-1敲低空载组、PI3K/AKT通路抑制剂组(PD-1敲低+5μmol/L LY294002)。通过在高糖培养基中培养大鼠骨髓间充质干细胞来模拟体外糖尿病环境,采用qRT-PCR检测大鼠骨髓间充质干细胞中PD-1及其配体PD-L1和成骨标志物Runx2、OSX的mRNA表达,采用碱性磷酸酶染色和茜素红S染色观察成骨分化能力,采用CCK-8检测细胞增殖情况,采用Western blot检测PD-1、PD-L1、p-PI3K、p-AKT的蛋白表达。结果与结论:①高糖组PD-1及PD-L1表达显著高于正常糖组,高糖组骨髓间充质干细胞的成骨分化能力较正常糖组显著下降;②敲低PD-1表达可以促进骨髓间充质干细胞的成骨分化、增加细胞增殖活性,同时激活PI3K/AKT通路;③加入PI3K/AKT通路抑制剂LY294002后,骨髓间充质干细胞成骨分化能力显著下降。结果表明:PD-1依赖于PI3K/AKT信号通路抑制高糖环境下大鼠骨髓间充质干细胞的成骨分化。展开更多
文摘Objective To investigate effect of pinacidil, an ATP sensitive potassium channel （KATP） opener, on the neuronal apoptosis and its signaling transduction mechanism following focal cerebral ischemia-reperfusion in rats. Methods One hundred male Wistar rats were randomly divided into four groups： A, sham-operated group; B, ischemia-reperfusion group; C, KATe opener treatment group; and D, KATe opener and blocker treatment group. The middle cerebral artery occlusion （MCAO） model was established by using the intraluminal suture occlusion method, neuronal apoptosis was determined by TUNEL staining, and expressions of caspase-8, caspase-9 and caspase-3 mRNA were detected by in situ hybridization. Results （1） The numbers of apoptotic neurons at 12 h, 24 h, 48 h, and 72 h were significantly less in group C than in groups B and D （P 〈 0.01 or P 〈 0.05）; and there was no difference between groups B and D at all time points （P 〉 0.05）. （2） The expressions of caspase-3 mRNA and caspase-8 mRNA at all times and the expressions of caspase-9 mRNA at 12 h, 24 h, 48 h, 72 h were significantly lower in group C than in groups B and D （P 〈 0.01 or P 〈 0.05）; and there were no differences between groups B and D at all time points （P 〉 0.05）. Conclusions KATP opener can significantly decrease the neuronal apoptosis and the expressions of caspase-3, caspase-8 and caspase-9 mRNAs following cerebral ischemiareperfusion. The neuronal apoptosis may be decreased by the inhibition of both mitochondrial and death-receptor signal pathways.
