黄嘌呤氧化酶在激素诱导成骨细胞凋亡过程中的作用及机制

目的探究黄嘌呤氧化酶在糖皮质激素诱导小鼠胚胎成骨细胞前体细胞(MC3T3-E1)细胞凋亡过程中的作用及机制。方法将细胞分为空白组、模型组、5 mol/L组、10 mol/L组和15 mol/L组,接种完成后培养24 h,确认细胞贴壁后换液。空白组加入10%FBS培养基2 mL,模型组加入1 10-6 mol/L DEX培养基2 mL, 5 mol/L组加入5 mol/L别嘌醇DEX培养基2 mL,10 mol/L组加入10 mol/L别嘌醇DEX培养基2 mL,15 mol/L组加入15 mol/L别嘌醇DEX培养基2 mL。培养72 h后检测Caspase-3、STAT-1、Bax、Bcl-2等蛋白表达情况,检测细胞凋亡情况以及活性氧簇含量。检测细胞内黄嘌呤氧化酶活性、丙二醛(MDA)含量及线粒体膜电位。结果模型组中Caspase-3、STAT-1和Bax蛋白表达量明显升高,Bcl-2蛋白表达量降低,细胞凋亡比例增高,细胞内活性氧簇含量增高,细胞内黄嘌呤氧化酶活性、丙二醛含量增高,而线粒体膜电位降低,与空白组、5 mol/L组、10mol/L组和15 mol/L组相比,差异有统计学意义(P <0.05)。结论黄嘌呤氧化酶通过产生过量的活性氧簇从而导致成骨细胞氧化应激损伤,通过激活STAT-1和Bax蛋白来诱导成骨细胞凋亡,同时诱导线粒体膜电位稳态崩溃触发内源性线粒体凋亡途径。别嘌醇可以较好地抑制黄嘌呤氧化酶的活性,减少活性氧簇的产生,通过减少Caspase-3、STAT-1和Bax蛋白表达,稳定线粒体膜电位,从而减少成骨细胞凋亡。

The role and mechanism of XOD in glucocorticoid-induced apoptosis in MC3T3-E1 cells

Objective To investigate the role and mechanism of xanthine oxidase in glucocorticoid-induced apoptosis in MC3 T3-E1 cells.Methods MC3 T3-E1 cells were divided into blank control group,model group,5 mol/L group,10 mol/L group and 15 mol/L group.After the inoculation was completed,the cells were incubated in an incubator for24 hours.After confirming the attachment of the cells.Blank control group was added 2 mL 10%FBS medium.Model group was added 1×10^-6 mol/L DEX medium 2 mL.5 mol/L group was added 5 mol/L allopurinol DEX medium 2 mL.10 mol/L group was added 10 mol/L allopurinol DEX medium 2 mL.15 mol/L group was added 15 mol/L allopurinol DEX medium 2 mL.The related indicators,such as Caspase-3,STAT-1,Bax,Bcl-2,apoptosis,reactive oxygen species(ROS)contents,intracellular xanthine oxidase,malondialdehyde and mitochondrial membrane potential were detected after 72 hours of cultivation.Results In model group,the expression of Caspase-3,STAT-1 and Bax was significantly increased while the expression of Bcl-2 protein was decreased.The proportion of apoptotic cells and the content of intracellular reactive oxygen species were also increased.The activity of intracellular xanthine oxidase,malondialdehyde content was also increased.But the mitochondrial membrane potential was significantly decreased.These indicators were significant difference with other groups(P<0.05).Conclusion The xanthine oxidase may generate excessive ROS,which leads to cell oxidative stress injury and induce the apoptosis in MC3 T3-E1 cells through activating STAT-1 and Bax.The endogenous mitochondrial apoptosis pathway was triggered by mitochondrial membrane potential collapse.Allopurinol can inhibit the activity of xanthine oxidase and reduce the production of reactive oxygen species.It can reduce osteoblast apoptosis by decreasing the expression of STAT-1,Caspase-3 and Bax protein and stabilizing the mitochondrial membrane potential.