Effect of NLRP3 inflammatome in renal interstitial fibrosis induced by unilateral ureteral obstruction in rats and its mechanism
10.13481/j.1671-587X.20240301
- VernacularTitle:NLRP3炎症小体在大鼠单侧输尿管梗阻引起肾间质纤维化中的作用及其机制
- Author:
Yingxin RUAN
1
;
Junya JIA
;
Zhanfei WU
;
Wenya SHANG
;
Pengyu ZHANG
Author Information
1. 天津医科大学总医院肾内科,天津 300052
- Keywords:
Nucleotide combined with structure of oligomerization domain receptor protein 3;
Oxidative stress;
Transforming growth factor β1;
Unilateral ureteral obstruction;
Renal interstitial fibrosis
- From:
Journal of Jilin University(Medicine Edition)
2024;50(3):587-595
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To discuss the effect of NOD-like receptor protein 3(NLRP3)inflammasome on the renal interstitial fibrosis in the unilateral ureteral obstruction(UUO)model rats,and to clarify its potential mechanism.Methods:Thirty healthy male Wistar rats were randomly divided into sham operation group(n=6)and UUO group(n=24).The rats in sham operation group underwent the dissection of the ureter without ligation,while the rats in UUO group were sacrificed on the 3rd,7th,and 14th days after operation,and based on the treatment duration,the rats were divided into UUO 3 d group(n=8),UUO 7 d group(n=8),and UUO 14 d group(n=8).HE staining and Masson staining were used to observe the pathomorphology of kidney tissue of the rats in various groups;reagent kits were used to detect the levels of malondialdehyde(MDA),activities of superoxide dismutase(SOD),and levels of hydroxyproline(HYP)in kidney tissue of the rats in various groups;immunohistochemistry method was used to detect the expression levels of α-smooth muscle actin(α-SMA)and transforming growth factor-β1(TGF-β1)proteins in kidney tissue of the rats in various groups;Western blotting method was used to detect the expression levels of NLRP3 protein in kidney tissue of the rats in various groups.Results:The HE staining results showed significant tubular dilation,interstitial edema,and widening,with increased infiltration of inflammatory cells,and shedding of epithelial cells was seen in parts of the tubular lumina of the rats in UUO group.Compared with sham operation group,the interstitial fibrosis scores of the rats in UUO 3 d,UUO 7 d,and UUO 14 d groups were significantly increased(P<0.05);compared with UUO 3 d group and UUO 7 d group,the interstitial fibrosis score of the rats in UUO 14 d group was significantly decreased(P<0.05).The Masson staining results showed that in UUO group,there was evident infiltration of inflammatory cells in the renal interstitium and a noticeable increase in fibrotic tissue proliferation;with the increasing of duration of UUO,some tubular structures disappeared,and the interstitial widened further with gradually increasing collagen deposition,particularly at the corticomedullary junction.Compared with sham operation group,the interstitial fibrosis scores of the rats in UUO 3 d,UUO 7 d,and UUO 14 d groups were significantly increased(P<0.05);and compared with UUO 3 d and UUO 7 d groups,the interstitial fibrosis score of the rats in UUO 14 d group was significantly decreased(P<0.05).Compared with sham operation group,the levels of MDA in obstructed kidney tissue of the rats in UUO 3 d,UUO 7 d,and UUO 14 d groups were significantly increased(P<0.05),and the SOD activities were significantly decreased(P<0.05).Compared with sham operation group,the levels of HYP in obstructed kidney tissue of the rats in UUO 3 d,UUO 7 d,and UUO 14 d groups were also significantly increased(P<0.05);compared with UUO 3 d group,the level of HYP in obstructed kidney tissue of the rats in UUO 14 d group was significantly increased(P<0.05).The immunohistochemistry results showed that compared with sham operation group,the expression levels of α-SMA protein in kidney tissue of the rats in UUO 3 d,UUO 7 d,and UUO 14 d groups were significant increased(P<0.05);compared with UUO 3 d and UUO 7 d groups,the expression levels of α-SMA protein in kidney tissue of the rats in UUO 14 d group was significantly increased(P<0.05);compared with sham operation group,the expression levels of TGF-β1 protein in renal tubular epithelial cells and renal tubule interstitial tissue of the rats in UUO 3 d,UUO 7 d,and UUO 14 d groups were also significantly increased(P<0.05);compared with UUO 3 d group,the expression levels of TGF-β1 protein in the tubular epithelial cells and renal tubule interstitial tissue of the rats in UUO 14 d group were significantly decreased(P<0.05).The Western blotting results showed that compared with sham operation group,the expression levels of NLRP3 protein in kidney tissue of the rats in UUO 7 d and UUO 14 d groups were significantly increased(P<0.05).Conclusion:The NLRP3 inflammasome plays a critical role in renal fibrosis of the UUO rats,and its mechanism may be related to the increasing of oxidative stress and the increasing of expression level of TGF-β1 protein.
