Atorvastatin Attenuates Contrast Media Induced Apoptosis Of HKC Cells In A Microenvironment Of Serum-free And Hypoxia

[Objective] To investigate the effect and mechanism of atorvastatin on theapoptosis of renal tubular epithelial cell induced by contrast media in amicroenvironment of serum-free and hypoxia[Methods] HKC cells were exposed to different concentrations(10,20,40,80,120,150mgI/ml) of iohexol (a non-ionic low-osmolarcontrast media) under serum-free and hypoxia conditions.Cells of othergroups were incubated with iohexol(120mgI/ml) for0,1,2,4,8,12h,respectively. In separate experiments,HKC cells wereincubated with atorvastatin（10-8,10-7,10-6,10-5mol/L） for12h,andthen were cultured with iohexol(120mgI/ml) for2h and12h. cellproliferation was detected by cell counting kit-8. Apoptosiswas determined by flow cytometry Annexin-FITC/PI double stains.The intracellular ROS was detected by fluorescence microscope withfluorescence probe DCFH-DA. Bax、Bcl-2protein expression wasassessed with Western blotting.[Results] To some extent, iohexol induced HKC cells viability reduction andapoptosis in a concentration-and time-dependent manner underserum-free and hypoxia conditions. In comparison with incubating byiohexol under normal conditons, oxygen deficit and serum-freeaggravate the damage of HKC cells induced by iohexol.That wasshowed:the cells viability was inhibited more significantly（0.474±0.060VS0.312±0.076，P<0.05，n=3）;the apoptosis increased markedly（9.53%±1.19%VS18.83%±1.36%，P<0.05，n=3）; the intracellularROS generation was markedly increased; the Bax protein expression wasup-regulated more significantly（1.276±0.058VS1.468±0.076，P<0.05，n=4） and the Bcl-2protein expression was down-regulated more dramatically（0.117±0.022VS0.067±0.009，P<0.05，n=4）. Atorvastatinattenuates the iohexol induced HKC cells viability reduction,apoptosis,ROS generation,up-regulation of Bax protein anddown-regulation of Bcl-2protein in a dose-dependent manner（10-8~10-6mol/L）under serum-free and hypoxia conditions.There wasa positive correlation between the Bax protein and ROS level and anegative correlation between the Bcl-2protein and ROS level.[Conclusion] Iohexol induced HKC cells viability reduction and apoptosis in aconcentration-and time-dependent manner via triggering oxidativestress and up-regulation of Bax protein expression and down-regulationof Bcl-2protein expression under serum-free and hypoxia conditions.Atorvastatin can attenuate the above effects of iohexol.