Renalase: Another puzzle piece between hypertension and simple renal cysts?

Since renalase is mostly expressed in kidney tubules, simple renal cyst (SRC) originates from the kidney tubules, and both conditions are related to hypertension, it may be possible that SRC is associated with increased renalase levels. Therefore, in the current study we aimed to confirm the relation between renalase and epinephrine levels, the association between SRC and renalase levels and the association between renalase, blood pressure levels and endothelial dysfunction.

We made a cross-sectional study including 75 patients with SRC, and 51 controls were included to the study. Flow-mediated dilatation (FMD) was assessed, and serum renalase and epinephrine levels were determined.

Patient with SRC had lower renalase, higher epinephrine and lower FMD levels when compared to patients without SRC (p < 0.05). Log renalase was correlated with log epinephrine (r = -0.302, p = 0.001) and log FMD (r = 0.642, p < 0.0001). There was no correlation between renalase and urine albumin/creatinine ratio and glomerular filtration rate. In univariate analysis, age, glomerular filtration rate, renalase and FMD were associated with the presence of SRC. Multivariate regression analysis of factors which are statistically significant in univariate analysis showed that age and renalase was associated with the presence of SRC.

We have demonstrated that renalase levels were associated with the presence of SRC and endothelial dysfunction. Further research is necessary to highlight underlying mechanisms.