A meta-analysis of the effects of endothelial nitric oxide synthase 4ba polymorphism on renal interstitial fibrosis in diabetic nephropathy.

Abstract

This study aimed to investigate the relationship between endothelial nitric oxide synthase (eNOS) 4b/a gene polymorphism and renal interstitial fibrosis in patients with diabetic nephropathy (DN) via a meta-analysis, in the hope of providing guidance for the genotypic detection of DN. The Boolean logic search method was adopted. A literature search of PubMed, Medline, CNKI, and other databases from inception to June 2020 was performed using the search terms "eNOS 4b/a", "diabetes", "renal interstitial fibrosis", and "kidney disease". Literatures with a DN group, a non-nephropathy diabetic group, and a normal control group were screened. Review Manager software was employed to perform the meta-analysis. A total of 13 articles were included in the meta-analysis, the majority of which had a low risk of bias (i.e., medium and high quality). The results of the meta-analysis indicated that the genotypic distribution frequency of eNOS4bb in patients with DN was significantly lower than that in the non-nephropathy diabetic group (Z=3.19, P=0.001). The genotypic distribution frequency of eNOS4aa was significantly higher in non-nephropathy diabetic patients than in the normal control group (Z=2.57, P=0.01). The genotypic distribution frequency of eNOS4ba was not statistically different between patients with DN and non-nephropathy diabetic patients (Z=1.45, P=0.15). The genotypic distribution frequency of eNOS4bb in DN patients was significantly lower than that in the normal control group (Z=3.03, P=0.002); however, the genotypic distribution frequency of eNOS4ba was significantly greater than that of the normal controls (Z=2.36, P=0.02), as was that of eNOS4aa (Z=2.34, P=0.02). Genotypic polymorphism of eNOS 4b/a was closely related to DN. Moreover, the genotypic distribution frequency of eNOS4bb in DN renal interstitial patients was lower than that in non-nephropathy diabetic patients and normal controls.