Participation of NLRP3 inflammasome in the pathogenesis of idiopathic membranous nephropathy

Objective To observe the expression of NLRP3,TRAF6,ERK1/2,p38 and JNK signaling pathway proteins in renal biopsy tissues of patients with idiopathic membranous nephropathy (IMN) and explore the correlation between urinary protein and NLRP3,TRAF6 and NLRP3.Methods From 38 IMN patients naive to adrenal corticosteroids and immunosuppressive agents,renal biopsy specimens were collected for detecting the expressions of TRAF6,NLRP3,NF-κB,phosphorylated ERK1/2MAPK,phosphorylated p38MAPK and phosphorylated JNK through immunohistochemistry.Also the levels of 24-hour urinary protein,serum creatinine,creatinine clearance and urea nitrogen were recorded.Then correlation analysis of urinary protein with NLRP3 and TRAF6.Renal tissue specimens from 10 patients undergoing nephrectomy due to renal tuberculosis or renal tumors served as normal control.Results Compared with normal group,24-hour urinary protein and serum creatinine were significantly higher in patients with stage II IMN (P<0.001).The expressions of TRAF6 and NLRP3 were significantly greater than those of normal group (P<0.0001) and the difference was statistically significant.And 24-hour urinary protein quantity was positively correlated with NLRP3 (r=0.689,P<0.01) while TRAF6 positively correlated with NLRP3 (r=0.490,P<0.01).NF-κB,phosphorylated ERK1/2,phosphorylation of p38 and phosphorylated JNK were higher than normal group (P<0.001).Conclusion Probably involved in the pathogenesis of stage II IMN,NLRP3 and TRAF6 may be associated with NF-κB and the activations of ERK1/2,p38 and JNK signaling pathways.