The association of ACE gene polymorphism and serum ACE levels with diabetic nephropathy-a cross-sectional study

Abstract

Diabetic nephropathy (DN) is the microvascular complication of type-2 diabetes that leads to end-stage renal disease. The angiotensin-converting enzyme gene that is a part of the renin-angiotensin-aldosterone system is considered one of the candidate genes responsible for the genetic predisposition of DN. To compare serum angiotensin converting enzyme (ACE) levels, the pattern of ACE gene polymorphism in patients with type-2 diabetes with or without nephropathy, to find the association between ACE gene polymorphism and various stages of DN, the association between serum ACE levels and various stages of DN. We enrolled 108 patients diagnosed with type-2 diabetes and 108 DN patients. Serum levels were estimated by ELISA and gene polymorphism was performed with gene sequencing. It was found that the serum ACE levels were higher in DN patients than in type-2 diabetics although the p-value was not significant. There was no significant association between serum ACE levels and various stages of nephropathy. The wild (GG genotype) distribution was more predominant in type-2 diabetic patients than in DN patients. There was a significant difference in the frequency of genotype with various stages of nephropathy and estimated glomerular filtration rate which was statistically significant (p = 0.0018). In summary, the study did not find a significant association between serum ACE levels and DN, nor did it observe a substantial impact of ACE gene polymorphism on serum ACE levels in DN patients. The findings also indicated that the ACE gene polymorphism might not have a direct influence on albuminuria stages. However, the wild-type genotype showed a trend toward protection against albuminuria development, while the carrier patients had a higher prevalence of severe albuminuria. Further research with larger sample sizes and longitudinal studies may provide deeper insights into the role of serum ACE levels and ACE gene polymorphism in the development and progression of DN.