间充质干细胞对顺铂诱导的小鼠急性肾损伤中细胞铁死亡的作用

Effect of mesenchymal stem cells on ferroptosis in cisplatin-induced acute kidney injury of mice

目的观察间充质干细胞(MSCs)移植对顺铂诱导的小鼠急性肾损伤(AKI)中细胞铁死亡的作用。方法选取18只8周龄雄性C57BL/6小鼠随机分为模型组、MSCs治疗组和正常对照组,每组6只。腹腔注射顺铂构建小鼠AKI模型,治疗组于造模24h后腹腔注射MSCs(1×106),3 d后处死各组小鼠,取肾脏和血清。利用小动物活体成像系统观察MSCs在小鼠体内的分布和存活情况。检测血清肌酐(Scr)、血尿素氮(BUN),行肾组织PAS染色,透射电镜观察肾脏细胞的线粒体形态改变。检测肾组织的丙二醛(MDA)、还原型谷胱甘肽(GSH)和超氧化物歧化酶(SOD)水平,评估肾脏细胞铁死亡情况。Western印迹检测谷胱甘肽过氧化物酶4(GPX4)和核因子E2相关因子2(Nrf2)蛋白的表达。结果小动物活体成像结果显示移植的MSCs定植在腹腔内并产生效应。急性肾小管坏死评分和Scr、BUN水平比较:模型组显著高于对照组(P<0.01),MSCs治疗组则明显低于模型组(P<0.01)。与对照组相比,模型组肾组织的MDA水平显著升高,GSH和SOD水平则显著下降(P<0.01)。与模型组相比,MSCs治疗组的MDA水平显著下降(P<0.01),GSH(P<0.01)和SOD(P<0.05)水平显著上升。与对照组相比,模型组出现线粒体萎缩、膜密度增加、线粒体嵴减少等细胞铁死亡的特征表现,MSCs治疗组线粒体损伤减轻。与对照组相比,模型组的GPX4和Nrf2蛋白表达明显下调(均P<0.01),但是治疗组的GPX4和Nrf2蛋白表达则明显上调(P<0.05)。结论MSCs可以抑制肾脏细胞铁死亡,从而减轻顺铂引起的小鼠肾小管损伤。

Objective To investigate the effect of mesenchymal stem cells(MSCs)on ferroptosis in cisplatin-induced acute kidney injury(AKI)of mice.Methods Eighteen 8-week-old male C57BL/6 mice were randomly divided into a model group,an MSCs treatment group,and a control group with 6 mice each.The AKI model was induced by a single intraperitoneal injection of 20 mg/kg cisplatin.After 24 h of the cisplatin-induction,the treatment group was given a single intraperitoneal injection of 1×106 MSCs.The mice were sacrificed on day 3 with the kidneys and blood being collected.An in vivo fluorescence imaging system was used to observe the distribution and survival of MSCs in the mice.Serum creatinine(Scr)and blood urea nitrogen(BUN)were detected.Renal tissue was stained with PAS,and mitochondrial morphology of renal cells was observed by transmission electron microscope.The levels of malondialdehyde(MDA),reduced glutathione(GSH)and superoxide dismutase(SOD)in kidney tissues were detected to evaluate the ferroptosis.The protein expression of glutathione peroxidase 4(GPX4)and nuclear factor E2-related factor 2(Nrf2)was detected by Western blotting.Results The results of in vivo imaging system showed that MSCs transplanted were colonized in the abdominal cavity and played the role.The model group showed higher levels than the control group,while the treatment group showed lower levels than the model group,in Scr and BUN as well as the acute tubular necrosis scores(P<0.01).Compared with the control group,the model group had higher level of MDA,but lower levels of GSH and SOD(P<0.01).Compared with the model group,the treatment group had lower level of MDA(P<0.01),but higher levels of GSH(P<0.01)and SOD(P<0.05).Compared with the control group,the model group showed the characteristics of cell ferroptosis such as mitochondrial atrophy,membrane density increase,and reduced mitochondrial crista,which were alleviated in the treatment group.Compared with the control group,the expression of GPX4 and Nrf2 proteins in the model group was significantly down-regulated(P<0.01),but was up-regulated in the treatment group(P<0.05).Conclusion MSCs could alleviate the cisplatin-induced injury in the renal tubules of mice by inhibiting the cellular ferroptosis.