Endothelial injury and inflammation in patients with hyperuricemic nephropathy at chronic kidney disease stages 1-2 and 3-4

BACKGROUND Endothelial injury and inflammation are the main pathological changes in hyperuricemic nephropathy (HN); however, they have not been assessed in patients in the early, middle, and late phases of HN. AIM To investigate endothelial injury and inflammatory conditions between patients with HN at chronic kidney disease (CKD) stages 3-4 and CKD 1-2. METHODS This study enrolled 80 patients (49 and 31 with HN at CKD stage 1-2 and 3-4, respectively) from the Department of Nephrology, Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine between July 2021 and January 2022. Plasma levels of heparan sulfate, endocan, oxidized low-density lipoprotein (Ox-LDL), E-selectin, soluble intercellular adhesion molecule-1 (slCAM1), interleukin (IL)-1 beta, and IL-6 and urine levels of lipocalin-type prostaglandin D synthase (L-PGDS), IL-1 beta, and IL-6 were measured using enzyme-linked immunosorbnent assay. RESULTS Comparison between patients with HN at CKD 1-2 and those with HN at CKD 3-4 showed that age and disease course were significant factors (P < 0.001 and P < 0.010, respectively). There were no statistical differences in sex, heart rate, body mass index, and systolic and diastolic blood pressures. The incidence of hypertension was also significant (P = 0.03). Plasma levels of heparin sulfate (P < 0.001), endocan (P = 0.034), E-selectin (P < 0.001), slCAM1 (P < 0.001), IL-1 beta (P = 0.006), and IL-6 (P = 0.004) and the urine levels of L-PGDS (P < 0.001), IL-1 beta (P = 0.003), and IL-6 (P < 0.001) were high in patients with HN at CKD 3-4 than in those with HN at CKD 1-2. The difference in plasma Ox-LDL levels was not significant (P = 0.078). CONCLUSION Vascular endothelial injury and inflammation were higher in patients with HN at CKD3-4 than at CKD 1-2. Plasma heparin sulfate and slCAM1 levels are synergistic factors for CKD staging in HN.