Protective mechanism of NHE-1-siRNA on human renal tubular epithelial cell from ischemic reperfusion injury induced by antimycin A
- VernacularTitle:钠-氢交换蛋白1小干扰RNA对抗霉素A诱导人肾小管上皮细胞缺血再灌注损伤的保护机制
- Author:
Quan HONG
;
Di WU
;
Zhe FENG
;
Xueguang ZHANG
;
Yang WANG
;
Yang LV
;
Xiangmei CHEN
- Publication Type:Journal Article
- Keywords:
Na+-H+ exchanger 1;
Isehemia;
Reperfusion injuy;
Renal tubularepithelial cell;
Apoptosis
- From:Chinese Journal of Nephrology
2008;24(8):560-565
- CountryChina
- Language:Chinese
-
Abstract:
Objective To explore the mechanism of protecting cells from ischemic reperfusion injury by constructing specific small interference RNA (siRNA) to inhibit Na+-H+exchanger-1 (NHE-1) expression in human renal tubular epithelial cell (HKC). Methods The siRNA was designed and synthesized based on human NHE-1 complete sequence,and was transfected into HKC.The irrespective siRNA transfected group was used as control.The cells were treated with 10 μmol/L antimyein A to induce ischemia and anoxyaemia environment.NHE-1expression was examined by RT-PCR and Western blot.The intraeellular pH (pHi),Ca2+ or Na+ concentrations were detected by BCECF/AM,Fluo-3/AM and SBFI-AM,respectively,combining with laser eonfocal assay system.Nucleic morphology was determined by Hoechst 33342.Cellular apoptosis was examined by Annexin V/PI staining and flow eytometry.Fluorescent probe JC-1 was used to detect the change of mitechondrial transmembrane potential. Results The specific siRNA could efficiently inhibit NHE-1 expression in HKC.Compared with the irrespective siRNA transfected group,the mRNA and protein expression of NHE-1 was significantly down-regulated in NHE-1 siRNA transfeeted group (all P＜0.05).After treatment with antimyein A,the mRNA and protein expression of NHE-1 was significantly up-regulated in both groups,however,it was less than that in irrespective siBNA transfected group.At the same time,the ratio of apoptosis decreased (8.9% +2.9% vs 18.8%±3.2% , 17.4%±3.6% ,P＜0.05) and mitochondrial transmembrane potential rose significantly in NHE-1 siRNA transfected group as compared to irrespective siRNA transfected group and antimycin A group.The intracellular Na+,H+ and Ca2+concentrations increased in NHE-1 siRNA transfected group treated with antimyein A,but their levels were lower than those in irrespective siRNA transfected group with the same treatment(P＜0.05). Conclusions The synthesized siBNA can inhibit the expression of NHE-1 and can protect HKC from isehemia reperfasion injury induced by antimyein A.The mechanism might be via suppressing the expression of NHE-1 to delay intracelluar Na+ accumulation,attenuate intracellular Ca2+ overloading,and inhibit the decrease of mitechondrion transmembrane potential and reduce cellular apoptosis.
