Studies suggest that renalase, a renal catecholamine-inactivating enzyme, plays a major role in the pathogenesis of kidney and cardiovascular diseases in adults. This study seeks to determine the role of renalase in children with glomerular kidney diseases. We evaluated the serum renalase, arterial stiffness, intima-media thickness, blood pressure, and clinical and biochemical parameters in 78 children (11.9 ± 4.6 years of age) with glomerulopathies such as idiopathic nephrotic syndrome (40 cases), IgA nephropathy (12 cases), Henoch-Schönlein nephropathy (12 cases), and other glomerulopathies (14 cases). The control group consisted of 38 healthy children aged 11.8 ± 3.3 years. The mean renalase was 25.74 ± 8.94 μg/mL in the glomerulopathy group, which was not significantly different from the 27.22 ± 5.15 in the control group. The renalase level did not differ among various glomerulopathies either. However, proteinuric patients had a higher renalase level than those without proteinuria (28.43 ± 11.71 vs. 24.05 ± 6.23, respectively; p = 0.03). In proteinuric patients, renalase correlated with daily proteinuria. In the entire glomerulopathy group, renalase correlated with age, systolic central blood pressure (BP), diastolic peripheral and central BP, mean peripheral and central BP; peripheral diastolic BP Z-score, glomerular filtration rate, cholesterol, triglycerides, and pulse wave velocity. We conclude that in children with glomerulopathies renalase, although basically not enhanced, may underlie blood pressure elevation and arterial damage.
Keywords: Arterial stiffness; Blood pressure; Children; Glomerular kidney diseases; Intima-media thickness; Proteinuria; Renalase; Sympathetic system.