Association of GSTP1 gene with renal function in patients with diabetes mellitus

Abstract

Introduction of point genetic associations into clinical and laboratory diagnosis will allow the physician to determine the risk of severe diabetes mellitus and its complications with a focus on detection of the genetically determined disorder. The study was aimed to identify the molecular genetic markers of severe diabetic nephropathy in patients with type 1 and 2 diabetes mellitus (DM) based on the GSTP1 (I105V) gene assessment. Genotyping of the GSTP1 gene I105V locus was performed in patients with type 1 and 2 DM. Then we identified the features of oxidative status, free radical oxidation, and renal function in patients with various polymorphic variants of the studied gene. Patients with type 1 DM, who were carriers of the GSTP1 heterozygous polymorphic variant (Ile/Val), showed higher activity of the oxidative stress enzymes (glutathione-S-transferase, catalase) and malondialdehyde compared to homozygous carriers (р < 0.001, р < 0.001, р < 0.05). They also showed a significant increase in the levels of triglycerides (1.6-fold) and the glycated hemoglobin levels (1.1-fold) (p < 0.05). Patients with type 2 DM, who were carriers of the GSTP1 polymorphism homozygous for allele 2 (Val\Val), had a higher level of malondialdehyde (100.5 µmol/L, (р < 0.001)), which was associated with the more severe diabetic nephropathy (average glomerular filtration rate — 48 mL/min/1.73 m2, 24-h urinary albumin excretion — 0.9 g/L; р < 0.01). It has been proposed to assess the GSTP1 (I105V) gene in individuals with type 1 and 2 DM. This polymorphism that is heterozygous in individuals with type 1 DM and homozygous for allele 2 in individuals with type 2 DM is unfavorable in terms of the DM course and complications.