Ulinastatin attenuates hypoxia/reoxygenation-induced cardiomyocyte ferroptosis by up-regulating Cx43 expression

Ding Hui; Song Yulong; Wang Zhen; Song Wenying

doi:10.3969/j.issn.1009-0126.2024.05.018

Abstract：Objective To investigate the effect of ulinastatin(UTI)on hypoxia/reoxygenation(H/R)induced iron death of cardiomyocytes and analyze its protective mechanism.Methods Rat car-diomyocytes H9c2 were grouped into control group,H/R group,iron death inducer(Erastin)group,UTI group,UTI+Erastin group,UTI+siRNA negative control(si-NC)group,UTI+con-nexin 43(Cx43)small interfering RNA(si-Cx43)group.After corresponding interventions,cell viability,contents of reactive oxygen species(ROS),Fe2+and malondialdehyde(MDA),activities of lactate dehydrogenase(LDH),superoxide dismutase(SOD)and catalase(CAT),and mRNA and protein levels of Cx43,glutathione peroxidase 4(GPX4),ferritin heavy chain 1(FTH1)and acyl coenzyme A synthetase long chain family member 4(ACSL4)were detected in each group.Results Cell viability,activities of SOD and CAT,and mRNA and protein levels of Cx43,GPX4 and FTH1 were significantly decreased,while LDH activity,contents of ROS,MDA and Fe2+,and ACSL4 mRNA and protein levels were obviously increased in the H/R group than the control group(P＜0.01).UTI treatment resulted in notably enhanced cell viability[(71.40±8.05)％vs(42.63±6.71)％,P＜0.05],stronger activities of SOD and CAT,up-regulated mRNA and protein levels of Cx43,GPX4 and FTH1,reduced LDH activity,and declined contents of ROS,MDA and Fe2+,and reduced ACSL4 mRNA and protein levels(P＜0.05)when compared with the levels in the H/R group.Compared with the UTI group,cell vitality,SOD and CAT activities,and Cx43,GPX4,FTH1 mRNA and protein levels were significantly decreased,while LDH activity,contents of ROS,MDA and Fe2+.and ACSL4 mRNA and protein levels were significantly increased in the UTI+Erastin group and the UTI+si-Cx43 group(P＜0.05).Conclusion UTI may inhibit H/R induced ferroptosis in cardiomyocytes by up-regulating Cx43.