特异性lncSLC25a6在同型半胱氨酸诱导的大鼠心肌细胞铜死亡中的作用

Role of specific lncSLC25a6 in homocysteine-induced cuproptosis in rat cardiomyocytes

目的:探讨特异性长链非编码RNA SLC25a6(long noncoding RNA SLC25a6,lncSLC25a6)在同型半胱氨酸(homocysteine,Hcy)诱导的心肌细胞铜死亡中作用。方法:体外培养大鼠心肌细胞并分为对照(control)与Hcy组,干预细胞48 h后,采用Western blot及免疫荧光染色方法检测铜死亡相关蛋白铁氧还蛋白1(ferredoxin 1,FDX1)、热休克蛋白70(heat shock protein 70,HSP70)等的表达水平;利用荧光染色检测心肌细胞氧化应激状态;采用铜离子试剂盒测定心肌细胞内Cu^(2+)水平;进一步将lncSLC25a6过表达后,分析Hcy对心肌细胞铜死亡相关蛋白表达的影响。结果:与control组相比,80μmol/L Hcy显著加速了心肌细胞损伤,且lncSLC25a6呈低表达(P<0.05)。Western blot检测结果显示:与control组相比,Hcy干预组FDX1表达水平明显降低(P<0.05),而HSP70表达水平明显增高(P<0.05),且Hcy组心肌细胞铜离子表达水平增高(P<0.05)。免疫荧光染色发现,Hcy组FDX1荧光强度明显减弱,HSP70的荧光强度明显增强;进一步过表达lncSLC25a6后,Hcy诱导的心肌细胞铜死亡显著缓解,细胞铜死亡相关蛋白FDX1呈高表达,HSP70呈低表达(P<0.05)。Pearson相关性分析发现,lncSLC25a6的表达水平与FDX1蛋白表达呈负相关(r=−0.676,P=0.046),而与HSP70表达则呈正相关(r=0.680,P=0.044)。结论:lncSLC25a6可显著缓解Hcy诱导的心肌细胞铜死亡,可作为Hcy诱导心肌损伤的潜在治疗靶点。

AIM:To investigate the role of specific long noncoding RNA SLC25a6(lncSLC25a6)in homocysteine(Hcy)-induced cuproptosis in cardiomyocytes.METHODS:Rat cardiomyocytes were cultured in vitro and divided into control group and Hcy group.After 48 h of intervention,the expression levels of cuproptosis-related proteins,ferredoxin 1(FDX1)and heat shock protein 70(HSP70),were detected by Western blot and immunofluorescence staining.The oxidative stress state of cardiomyocytes was assessed using fluorescence staining,and the intracellular Cu^(2+)levels were measured using a copper ion assay kit.Furthermore,the impact of Hcy on the expression of cuproptosis-related proteins in cardiomyocytes was analyzed following overexpression of lncSLC25a6.RESULTS:Compared with the control group,80μmol/L Hcy significantly accelerated cardiomyocyte damage,with a notable underexpression of lncSLC25a6(P<0.05).Western blot results indicated that,compared with the control group,the expression level of FDX1 in the Hcy intervention group was significantly reduced(P<0.05),while the expression level of HSP70 was significantly elevated(P<0.05),and the expression level of copper ions in cardiomyocytes of the Hcy group was increased(P<0.05).Immunofluorescence staining showed a significant reduction in FDX1 fluorescence intensity and a significant increase in HSP70 fluorescence intensity in the Hcy group.Further overexpression of lncSLC25a6 significantly mitigated Hcy-induced cuproptosis in cardiomyocytes,resulting in elevated expression of FDX1 and reduced expression of HSP70(P<0.05).Pearson correlation analysis demonstrated that the expression level of lncSLC25a6 was negatively correlated with FDX1 protein expression(r=-0.676,P=0.046)and positively correlated with HSP70 expression(r=0.680,P=0.044).CONCLUSION:lncSLC25a6 significantly mitigates Hcy-induced cuproptosis in cardiomyocytes,positioning it as a potential therapeutic target for managing Hcy-induced cardiac injury.