摘要
目的:探讨14-3-3γ对脂多糖(LPS)所致心肌损伤的作用与抑制Bax向线粒体移位的关系。方法:采用原代SD乳鼠心肌细胞,随机分为4组:对照组;LPS组,LPS10mg/L加至培养基中6h;pFLAG+LPS组,空载质粒pFLAG转染至心肌细胞,24h后处理同LPS组;pFLAG-14-3-3γ+LPS组,重组质粒pFLAG-14-3-3γ转染至心肌细胞,24h后处理同LPS组。四唑盐(MTT)比色法检测各组细胞存活率,全自动生化分析仪检测乳酸脱氢酶(LDH)、肌酸磷酸酶(CPK)值,流式细胞仪检测细胞凋亡率,Western blotting检测细胞14-3-3γ蛋白水平、细胞浆及线粒体的Bax蛋白水平。结果:LPS致心肌细胞损伤,与对照组相比,LPS处理使细胞存活率明显下降(P<0.01),LDH、CPK值明显升高(P<0.01),细胞凋亡率增加(P<0.01),促使Bax蛋白从胞浆向线粒体移位,转染重组质粒pFLAG-14-3-3γ使14-3-3γ在心肌细胞内高表达后可明显逆转LPS所致的损伤,上述各指标均有所改善,并抑制Bax蛋白向线粒体的移位。结论:14-3-3γ对抗LPS所致心肌细胞损伤与抑制Bax从胞浆向线粒体移位有关。
Objective: To investigate the protective effect of 14-3-3γ on cardiomyocyte against lipopolysaccharide (LPS) injury, and the relationship with the suppression of Bax translocation into mitochondria. Methods: The primary neonatal SD rat cardiomyocytes were randomly divided into 4 groups: control group, cardiomyocytes treated with 10 mg/L LPS for 6 h (LPS group), pFLAG transfected into cardiomyocytes for 24 h (pFLAG+LPS group) and pFLAG-14-3-3γ tnsfected into cardiomyocytes for 24 h (pFLAG-14-3-3γ+LPS group). After treatment, the cell viability was analyzed by methyl thiazoyl tetrazolium (MTF), the activity of lactic acid dehydrogenase (LDH) and creatine phosphate kinase (CPK) were deteImined by auto-biochemistry analysator, apoptotic cells were measured by flow cytometry and levels of 14-3-3γ protein in cardiomyocytes, Bax protein in cytoplasm and mitochondria were detected by Western blotting. Results: Compared with control group, the cell viability was significantly reduced in cardiomyocytes treated with LPS (P 〈 0.01), LDH and CPK activities were significantly increased (P 〈 0.01), the apoptotic cell ratio was enhanced (P 〈 0.01) and then Bax translocation from cytoplasm to mitochondria was promoted. The elevated 14-3-3γ protein resulted by transfection of pFLAG-14-3-3γ reversed cardiomyocyte damage induced by LPS, and inhibited Bax translocation from cytoplasm to mitochondria. Conclusion: 14-3-3γ protects cardiomyocytes against LPS damage by inhibiting Bax translocation from cytoplasm to mitochondria.
出处
《天津医药》
CAS
北大核心
2012年第12期1222-1225,共4页
Tianjin Medical Journal
基金
国家自然科学基金资助项目(项目编号:81160402
81072632
81100104)
博士后基金资助项目(20110491496)