Rs10887800 renalase gene polymorphism influences the level of circulating renalase in patients undergoing hemodialysis but not in healthy controls

BACKGROUND Human renalase (RNLS), a recently identified flavoprotein with oxidoreductase activity, is secreted into blood by kidneys and metabolizes circulating catecholamines. Recent studies have revealed that common polymorphisms in RNLS gene might affect the risk of several cardiovascular conditions in hemodialyzed patients. However, the exact mechanism underlying this link remains unclear. The study aims to investigate the association between RNLS gene polymorphisms and plasma renalase level in ESKD patients undergoing hemodialysis (HD group) and healthy controls (HC). METHODS A total of 309 hemodialyzed patients and 90 controls were enrolled in the study. All the participants were genotyped for two RNLS SNPs (rs2576178 and rs10887800) using PCR-RFLP method. Plasma renalase concentrations were determined by enzyme-linked immunosorbent assay (USCN Life Science Inc., Wuhan, China). The IBM SPSS Statistics for Windows, version 20 (IBM Corp., Armonk, NY, USA) was used for statistical analyses. RESULTS Genotype distribution and allele frequencies of studied SNPs did not differ between two analyzed groups, p > .050. RNLS concentration in HD group (33.54 μg/mL) was significantly higher than in HC (13.16 μg/mL), p < .001. HD patients with rs10887800AA genotype had lower renalase level (29.32 μg/mL) compared to those with AG (34.52 μg/mL), p < .010 and GG genotype (35.91 μg/mL), p < .010. No significant differences in plasma RNLS between rs10887800AG and GG carriers were observed, p > .050. Interestingly, in HC group rs10887800 polymorphism did not influence RNLS concentration. Rs2576178 SNP did not affect the level of plasma RNLS either in HD group or in HC. CONCLUSION Rs10887800 polymorphic variant of RNLS gene influences the level of circulating RNLS in patients undergoing hemodialysis, and thus elucidates the potentially functional relevance of this polymorphism in HD population.