Serum Renalase Levels in Adolescents with Primary Hypertension.

The prevalence of hypertension in pediatric populations continues to rise. Recent studies suggest that renalase plays an important role in blood pressure regulation. The aim of this study was to evaluate serum renalase concentrations in hypertensive children. This study was a prospective cohort analysis of 88 adolescents (40 girls; 48 boys) aged 11-18 years, divided into two groups: HT-38 subjects with primary hypertension; and R (reference group)-50 subjects with normal blood pressure. Serum renalase concentration was measured using a commercial enzyme-linked immunosorbent assay kit. Hypertensive patients had higher serum renalase levels (median 29.8 µg/mL; Q1-Q3: 26.1-35.8) than the reference group (median 26.8; Q1-Q3: 22.96-29.4, p < 0.01). Serum renalase was strongly related to serum uric acid levels. In hypertensive patients, serum renalase was positively correlated with 24-h systolic blood pressure (SBP) and 24-h diastolic blood pressure (DBP) and with 24-h SBP and 24-h DBP Z-score (LMS). Our results allow us to conclude that serum renalase correlates with blood pressure elevation. Special attention should be drawn to the correlation between renalase and serum uric acid levels not only in hypertensive, but also in normotensive teenagers. Further studies are needed to answer the question of whether increased serum renalase may be a predisposing factor to hypertension in normotensive patients with hyperuricemia.

The Possible Impact of Hyperuricemia on Serum Soluble Receptor for Advanced Glycation end Products (sRAGE) Levels in Teenagers: A Case Control Study.

BACKGROUND: Dietary advanced glycation end products (AGEs) and their interactions with the soluble receptors for AGEs (RAGE) play a crucial role in the pathogenesis of cardiovascular diseases. OBJECTIVE: This study was set out to assess, whether there was any association between serum sRAGE level and serum uric acid level in children with hyperuricemia. METHODS: This case-control study involved 53 patients (12 girls, 41 boys) with hyperuricemia (defined as serum uric acid >4.8 and >5.5 mg/dl in girls and boys, respectively) aged (median [IQR]) (15.5 [13.5-15.5] years). Thirty-six healthy individuals with normal serum uric acid level were selected as a reference group. Additionally, the study group with hyperuricemia was divided into two groups: HU-HT (hypertensive n=25) and HU-NT (normotensive n=28) teenagers. The serum concentration of human sRAGE was measured using a commercially available enzyme-linked immunosorbent assay (ELISA) kit. RESULTS: We found statistically significant differences in serum sRAGE levels between normotensive subjects with hyperuricemia (median [IQR]) (169.8 [148.3-231.1] pg/ml) and reference group (median [IQR]) (129 [107.4-175.3] pg/ml), p<0.01. Univariate analysis of the data revealed a positive correlation between serum sRAGE and serum uric acid in the study group (r=0.306, p<0.05). CONCLUSION: Our data showed that serum soluble receptors for AGEs are increased in teenagers with hyperuricemia. In contrast, neither hypertension nor increased BMI had a significant influence on serum sRAGE concentration. Further studies are needed to discover the possible mechanism on the influence of uric acid on sRAGE levels and to assess its possible clinical significance.