摘要
目的:观察西洋参茎叶总皂苷(PQS)对缺氧/复氧(H/R)心肌细胞的保护作用,并从内质网应激(ERS)的角度探讨其分子机制。方法:建立心肌细胞缺氧/复氧(H/R)损伤模型,以台盼蓝染色法、乳酸脱氢酶活性以及流式细胞术检测细胞损伤及凋亡情况;以RT-PCR和Western blotting方法,检测ERS标志分子葡萄糖调节蛋白78(GRP78)、钙网蛋白(CRT)、C/EBP同源蛋白(CHOP)、caspase-12及凋亡相关蛋白Bcl-2、Bax的表达。结果:和H/R组心肌细胞相比,PQS+H/R组:(1)细胞凋亡率降低4.19%(P<0.05),存活率升高21.2%(P<0.05),LDH活性降低66.58%(P<0.05);(2)Bcl-2 mRNA和蛋白表达分别升高30.9%和48.0%(P<0.05),Bax mRNA和蛋白表达分别降低39.7%和48.4%(P<0.05);(3)GRP78 mRNA和蛋白表达分别降低61.6%和37.7%(P<0.05),CRT mRNA和蛋白表达分别降低35.7%和52.2%(P<0.05);CHOP mRNA和蛋白表达分别降低57.0%和51.7%(P<0.05);剪切后的caspase-12蛋白表达降低34.9%(P<0.05)。结论:PQS可减轻H/R诱导的心肌细胞损伤,其机制是降低H/R诱导的GRP78、CRT mRNA和蛋白表达,抑制CHOP、caspase-12等内质网凋亡通路激活,从而抑制过度ERS介导的细胞凋亡。
AIM： To investigate the effect of Panax quinquefolium saponin（PQS） on hypoxia/reoxygenation injury and excessive endoplasmic reticulum stress（ERS） in rat cardiomyocytes.METHODS： Cultured cardiomyocytes of neonatal Sprague-Dawley rats were used to establish hypoxia/reoxygenation（H/R） model.The cardioprotective effects of PQS were observed.The morphological changes,the activity of lactate dehydrogenase（LDH） and cell apoptosis were assessed.The mRNA and protein expression levels of glucose-regulated protein 78（GRP78）,calreticulin（CRT）,C/EBP homologous protein（CHOP）,caspase-12 and apoptosis-associated protein Bax and Bcl-2 were determined by RT-PCR and Western blotting.RESULTS： Compared with H/R cardiomyocytes,PQS decreased the apoptosis rate and the LDH activity in the culture medium of H/R cardiomyocytes by 4.19% and 66.58%,respectively.The survival rate was increased by 21.2%.PQS increased mRNA and protein expression levels of Bcl-2 in H/R cardiomyocytes by 30.9% and 48.0%,and decreased those of Bax by 39.7% and 48.4%.PQS decreased mRNA and protein expression levels of GRP78 in H/R cardiomyocytes by 61.6% and 37.7%,those of CRT by 35.7% and 52.2%,and those of CHOP by 57.0% and 51.7%.The protein level of cleaved caspase-12 was decreased by 34.9%.CONCLUSION： PQS attenuates H/R-induced cardiomyocyte injury by inhibition of excessive ERS.
出处
《中国病理生理杂志》
CAS
CSCD
北大核心
2012年第1期22-28,共7页
Chinese Journal of Pathophysiology
基金
国家自然科学基金资助项目(No.30772868
No.81070186)
关键词
西洋参茎叶总皂苷
缺氧/复氧
内质网应激
心肌细胞
Panax qulinqufolium saponin
Hypoxia/reoxygenation
Endoplasmic reticulum stress
Cardiomyocytes
