Effect and mechanism of adrenomedullin on apoptosis of renal tubular epithelial cell in rats induced by renal ischemia reperfusion injury
10.3760/cma.j.issn.1000-6702.2011.07.005
- VernacularTitle:肾上腺髓质素对大鼠肾缺血再灌注损伤中肾小管上皮细胞凋亡的影响及机制研究
- Author:
Haihong ZHAO
;
Xi QIAO
;
Rongshan LI
;
Li ZHAO
;
Shan SHAO
;
Xinyan LIU
- Publication Type:Journal Article
- Keywords:
Adrenomedullin;
Reperfusion injury;
Apoptosis;
Caspase
- From:
Chinese Journal of Urology
2011;32(7):449-453
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the effect and mechanism of adrenomedullin (AM) on apoptosis of renal tubular epithelial cell in rats induced by renal ischemia reperfusion injury. Methods Thirty-two Wistar rats were randomly divided into 4 groups: control group, IRI group, empty plasmid group and AM group. One week after removing the right kidney, eukaryotic expression vector encoding rat AM gene was transfected into the left kidney using an ultrasound-microbubble mediated system. After 1 week the transfer efficiency was detected by immunohistochemical method . Renal IRI model induced by clamping left renal arteries for 45 min followed by reperfusion for 24 h. Tubular cell apoptosis was detected by TUNEL assay. Bcl-2, Bax and Fas expressions were examined by RT-PCR. The expressions of caspase-3, caspase-8 and caspase-9 were determined by Western bolt analysis. Results The expression of AM in the AM group was significantly higher than the empty plasmid group (0.51±0.09 vs 0.23±0.05; P<0.05). Compared with the control group, the apoptosis rate of renal tubular cell in the IRI group was significantly higher [(38.79±7.52)% vs (2.89±0.52)%; P<0.05]. The expressions of Bax, Bcl-2, Fas, caspase-3, caspase-8 and caspase-9 were also significantly increased (0.72±0.18 vs 0.23±0.04, 0.80±0.12 vs 0.38±0.06, 1.24±0.25 vs 0.39±0.09, 0.76±0.13 vs 0.38±0.08, 0.92±0.14 vs 0.32±0.06, 0.89±0.12 vs 0.42±0.09; P<0.05). Bax/Bcl-2 was also significantly increased (0.91±0.18 vs 0.61±0.08; P<0.05). Compared with the IRI group, AM pretreatment significantly decreased the apoptosis rate of renal tubular cells [(19.36±6.78)% vs (38.79±7.52)%; P<0.05]. AM inhibited the up-regulation of Bax, Fas, caspase-3, caspase-8 and caspase-9, while promoting the up-regulation of Bcl-2 (0.48±0.11 vs 0.72±0.18, 0.62±0.07 vs 1.24±0.25, 0.53±0.08 vs 0.76±0.13, 0.46±0.08 vs 0.92±0.14, 0.51±0.12 vs 0.89±0.12, 1.23±0.25 vs 0.80±0.12; P<0.05). Bax/Bcl-2 significantly decreased (0.44±0.12 vs 0.91±0.18; P<0.05). The above parameters had no significant diffe-rence between the empty plasmid group and the IRI group (P>0.05). Conclusion AM can reduce apoptosis of renal tubular epithelial cell induced by renal IRI, the mechanism of which might be achieved by inhibiting caspase-dependent intrinsic and extrinsic pathways.
