摘要
目的:探讨茶多酚(tea polyphenol,TP)在草酸和一水草酸钙(calcium oxalate monohydrate,COM)晶体诱导人近端肾小管上皮细胞(HK-2)损伤中的保护作用。方法:实验共分为4组:阴性对照组、阳性对照组(COM晶体+草酸溶液)、茶多酚组(茶多酚+COM晶体+草酸溶液)、维生素E组(维生素E+COM晶体+草酸溶液)。应用MTT法于4、8、12和24 h检测各组细胞活性,同时测定上清液中乳酸脱氢酶(lactate dehydrogenase,LDH)浓度、Na+/K+ATP酶活性以评估细胞膜完整性和损伤程度;测定过氧化氢(H2O2)、丙二醛(methane dicarboxylic alde-hyde,MDA)浓度及超氧化物歧化酶(superoxide dismutase,SOD)活性以判定脂质过氧化程度。透射显微镜下观察4和12 h每组细胞形态结构的变化。结果:HK-2细胞经过草酸及COM晶体处理后,各个时间点细胞活性、Na+/K+ATP酶及SOD活性均明显下降,LDH、MDA及H2O2浓度升高;与阳性对照组相比,茶多酚组细胞活性、Na+/K+ATP酶活性及SOD活性均明显升高,LDH、MDA及H2O2浓度明显降低;维生素E组细胞活性、Na+/K+ATP酶活性较阳性对照组变化不大,但SOD活性较阳性对照组明显升高,LDH、MDA及H2O2浓度较阳性对照组明显降低。透射显微镜观察发现各组HK-2细胞形态结构均出现不同程度变化,茶多酚组、维生素E组出现空泡、线粒体肿胀、核膜及细胞膜溶解、核仁消失的细胞数明显少于阳性对照组;同一时间点茶多酚组细胞结构异常改变要小于维生素E组。结论:茶多酚及维生素E能够通过抑制COM晶体及草酸诱导的脂质过氧化反应和提高细胞内抗氧化酶活性减少细胞损伤,茶多酚清除氧自由基对上皮细胞损伤的能力要强于维生素E。
Objective：To test whether the antioxidants tea polyphenol（TP） can provide protection against oxalate and calcium oxalate monohydrate（COM） crystals toxicity in HK-2 cells.Methods： Four groups were chosen for the study： Negative control group,positive control group（COM＋oxalate）,TP group（TP＋COM＋oxalate）,VitE group（vitamin E＋COM＋oxalate）.HK-2 cells were exposed for 4,8,12 and 24 h.The viability of the cells was assessed by MTT.The cellular injury was assessed by the concentration of lactate dehydrogenase（LDH）,hydrogen peroxide and viability of Na＋/K＋ ATP enzyme.The peroxidation level was assessed by malondialdehyde（MDA） content and viability of superoxide dismutase（SOD）.The morphological changes of HK-2 cells after being exposed for 4 and 12 h in each group were observed by transmission electron microscope（TEM）.Results： The effects of TP and vitamin E on oxalate and COM exposed cells were tested.The HK-2 cells exposed to oxalate and COM showed a significant reduction in viability of cells,Na＋/K＋ ATPase and SOD.LDH release,MDA content and concentration of H2O2 were significantly increased.In TP group,the addition of TP significantly increased viability of cells,activity of Na＋/K＋ ATPase and SOD while LDH release,MDA content and concentration of H2O2 were significant decreased compared with the positive control group.In the Vitamn E group,compared with the positive control group,viability of cells,and activity of Na＋/K＋ ATPase were not significantly changed and after addition of vitamin E,SOD activity was restored,LDH release,MDA content and concentration of H2O2 were significant decreased compared with the positive control group.The morphological changes of HK-2 cells were observed by TEM in the positive control group,TP group and VitE group.In the VitE and TP groups,the amount of the cells with vacuoles formed in kytoplasms,mitochondria swelling,karyotheca dissolved and nucleolus disappearing were less than in the positive group.The morphological c
出处
《北京大学学报（医学版）》
CAS
CSCD
北大核心
2013年第4期567-574,共8页
Journal of Peking University:Health Sciences
关键词
茶多酚
草酸钙
脂质过氧化作用
肾小管
肾结石
Tea polyphenol
Calcium oxalate
Lipid peroxidation
Kidney tubules
Kidney calculi
