Analysis of Biomarkers of Oxidative Stress and Inflammation in Mexican Patients With Type 2 Diabetes and Chronic Kidney Disease

BACKGROUND: Oxidative stress (OS) and persistent low-grade inflammation are frequently observed in hyperglycemic conditions such as diabetes. The persistent hyperglycemic environment in patients with diabetes stimulates the production of advanced glycation end-products and reactive oxygen species, which could disturb the redox balance and lead to OS. In turn, OS can dysregulate the inflammatory response and promote tissue damage, leading to common complications in diabetes. This study aims to evaluate OS and proinflammatory cytokines in adult patients with diabetes and chronic kidney disease (CKD). OBJECTIVE: This study aimed to analyze the levels of OS and inflammation biomarkers in Mexican patients with type 2 diabetes (T2D) and CKD. METHODS: Serum levels of superoxide dismutase (SOD), malondialdehyde (MDA), interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α were determined using Luminex and enzyme-linked immunosorbent assay in a sample of 147 Mexican patients with T2D. Patients were divided into two groups: those with CKD (n = 81) and those without CKD (n = 66). Levels of analyzed biomarkers were compared between the groups. Correlations and multivariate linear regression analyses were performed. RESULTS: Chronicity of disease, systolic blood pressure (SBP), uric acid levels, and prevalence of hypertension and hyperuricemia were higher in patients with CKD. SODs levels were higher in patients with CKD, whereas no difference in MDA concentrations was observed. IL-6 and TNF-α were significantly higher in patients with CKD. SOD levels positively correlated with SBP, uric acid, and TNF-α but negatively with glycated hemoglobin and estimated glomerular filtration rate (eGFR). Besides the major factors associated with CKD, such as duration of diabetes, hyperuricemia, and high blood pressure, elevated levels of IL-1β, IL-6, TNF-α, and SOD were also associated. Of the biomarkers analyzed, SOD and TNF-α were strong predictors of eGFR decline in patients with diabetes. CONCLUSION: Serum concentrations of SOD and the proinflammatory cytokines IL-1β, IL-6, and TNF-α were increased in patients with T2D and CKD and could be considered good biomarkers of OS and inflammation status. Monitoring of these molecules could contribute to better management of patients with T2D.