摘要
目的探讨去氢骆驼蓬碱(HM)对PC12细胞线粒体功能损伤和线粒体融合分裂相关蛋白表达水平的影响。方法PC12细胞分为细胞对照组、HM组、线粒体分裂抑制剂Mdivi-1组、HM+Mdivi-1组、线粒体裂变激动剂WY14643组、HM+WY14643组,药物浓度均为1、10、25、50、100μmol·L^(-1),处理24 h,噻唑蓝(MTT)法检测细胞存活率,显微镜观察细胞形态;MitoTracker Red探针染色观察线粒体形态和纵横轴长度比值,JC-1染色检测线粒体膜电位,试剂盒检测ROS、ATP水平和乳酸脱氢酶(LDH)活性,免疫荧光染色法和Western blotting检测胱天蛋白酶3(caspase-3)、促凋亡蛋白(Bax)、细胞色素C(cyt-c)和线粒体融合蛋白(Mfn2)、线粒体分裂蛋白(Drp-1)的表达水平;电穿孔法转染Drp1的干扰序列,筛选转染效果好的siRNA序列,协同药物干预,通过荧光法、MTT法、免疫印迹法检测相关指标。结果MTT结果显示,与细胞对照组比较,HM组、Mdivi-1组、HM+Mdivi-1组、WY14643组和HM+WY14643组存活率显著下降(P<0.01),EC 50分别为(11.48±2.32)、(12.35±1.67)、(14.88±2.07)、(39.14±3.25)、(20.09±1.97)μmol·L^(-1),依此后续实验选择20μmol·L^(-1)浓度的HM、Mdivi-1和HM+Mdivi-1作为构建PC12细胞模型的工作浓度;显微镜和MitoTracker Red探针染色观察发现,药物组细胞密度呈不同程度减少,树枝状突起减少变圆;线粒体形态趋向圆形,纵横轴长度比值分别为细胞对照组(3.33±0.72)、HM组(2.19±0.58)、Mdivi-1组(2.45±0.44)、HM+Mdivi-1组(1.43±0.62)。JC-1染色检测结果显示,与细胞对照组相比,HM组线粒体模电位显著下降(P<0.01);ROS显著升高(P<0.01)、ATP水平下降(P<0.01),LDH酶活性上升(P<0.01);免疫荧光染色法和Western blotting结果显示,与细胞对照组比较,HM组促凋亡蛋白Bax、细胞色素C、胱天蛋白酶3表达水平均显著上升(均P<0.01);与细胞对照组比较,HM组细胞线粒体分裂相关蛋白Drp1表达水平显著上升(P<0.01),而线粒体融合相关蛋白Mfn2的表达水平显著下降(P<0.01);特异性干扰Drp1并协同HM干预后,各干扰组较各单独药物干预组PC12细胞存活率下降,Drp1和Mfn2表达下调,均差异有统计学意义(P<0.05或P<0.01)。结论HM可通过ROS累积降低PC12细胞膜电位及ATP,进而激活caspase-3凋亡途径促使细胞凋亡,线粒体融合分裂可能参与HM造成PC12细胞的损伤,启动细胞线粒体途径凋亡。
Objective To investigate the effects of harmine(HM)on the expression level of mitochondrion fusion related proteins and mitochondrial function injury in PC12 cells.Methods PC12 cells were divided into cell control group,HM group,mitochondrion mitosis inhibitor Mdivi-1 group,HM+Mdivi-1 group,mitochondrion fission agonist WY14643 group,HM+WY14643 group,with drug concentrations of 1,10,25,50,100μmol·L^(-1).After 24 h treatment,the MTT method was used to detect the cell survival rate,and a microscope was used to observe the cell morphology,MitoTracker Red probe staining was used to observe the mitochondrial morphology and the length ratio of vertical and horizontal axes,JC-1 staining was used to detect the mitochondrial membrane potential,and a kit was used to detect ATP level and lactate dehydrogenase(LDH)activity.Immunofluorescence staining and Western blotting were used to assess the expression levels of caspase-3,apoptosis-promoting protein(Bax)cytochrome C(cyt-c),mitochondrial fusion protein(Mfn2)and mitochondrial mitotic protein(Drp-1).The interference sequence of Drp1 was transfected by electroporation,and the siRNA sequence with good transfection effect was screened.The related indicators were detected by fluorescence method,MTT method,and immunoblotting method in cooperation with drug intervention.Results MTT results showed that compared with the cell control group,the survival rate of HM group,Mdivi-1 group,HM+Mdivi-1 group,WY14643 group and HM+WY14643 group decreased significantly(P<0.01),and the EC 50 were(11.48±2.32),(12.35±1.67),(14.88±2.07),(39.14±3.25),(20.09±1.97),respectively.According to this,subsequent experiments selected 20μmol·L^(-1) for HM,WY14643 and HM+WY14643 as working concentrations to construct PC12 cell model.Microscopic observation and MitoTracker Red probe staining showed that the cell density in the drug group decreased in varying degrees,and a transition from branched to round morphology in the drug-treated groups was observed.The morphology of mitochondria tended to be round,and the ratio of the length of the longitudinal axis to transverse axis was(3.33±0.72)in the cell control group,(2.19±0.58)in the HM group,(2.45±0.44)in Mdivi-1 group,and(1.43±0.62)in HM+Mdivi-1 group,respectively.The results of JC-1 staining showed that compared with the cell control group,the mitochondrial mode potential of the HM group significantly decreased(P<0.01).ROS significantly increased(P<0.01)and ATP levels decreased(P<0.01),and LDH enzyme activity increased(P<0.01).Immunofluorescence staining and Western blotting results showed that compared with the cell control group,the expression levels of proapoptotic proteins Bax,cytochrome C,and caspase-3 in the HM group were significantly increased(all P<0.01).Compared with the cell control group,the expression level of mitochondrial fission related protein Drp1 in HM group was significantly higher(P<0.01).The expression level of mitochondrial fusion related protein Mfn2 significantly decreased(P<0.01).After specific interference with Drp1 and synergistic intervention with HM,the survival rate of PC12 cells in each interference group decreased compared to each drug intervention group.The expression of Drp1 and Mfn2 was downregulated,and the differences were statistically significant(P<0.05 or P<0.01).Conclusion HM can reduce the mitochoudrial membrane potential and ATP levels by accumulating ROS,there by activating the caspase-3 apoptosis pathway and promoting cell apoptosis.Mitochondrial fusion division may be involved in the damage of PC12 cells caused by HM,initiating apoptosis through the mitochondrial pathway.
作者
巩月红
赵美玲
马瑞佳
林玉霞
赵军
王建华
GONG Yuehong;ZHAO Meiling;MA Ruijia;LIN Yuxia;ZHAO Jun;WANG Jianhua(Department of Pharmacy,the First Hospital Affiliated with Xinjiang Medical University,Urumqi 830054,China;College of Pharmacy,Xinjiang Medical University,Urumqi 830054,China;Department of Pharmacy,the Seventh Hospital Affiliated with Xinjiang Medical University,Urumqi 830028,China)
出处
《医药导报》
北大核心
2024年第2期174-183,共10页
Herald of Medicine
基金
新疆维吾尔自治区科学技术厅自然科学基金面上项目(2020D01C240)
新疆维吾尔自治区科学技术厅自然科学基金重点项目(2021D01D15)
省部共建国家重点实验室开放课题(SKL-HIDCA-2022-9)。
