Effects of Irbesartan on Inflammatory Cytokine Concentrations in Patients with Chronic Glomerulonephritis

Abstract

OBJECTIVE: Some angiotensin receptor blockers (ARBs), including irbesartan, increase the peroxisome proliferator-activated receptor (PPAR)-g activity in vitro. The aim of this study was to evaluate the interactions between obesity and the effects of irbesartan on inflammatory cytokines in chronic glomerulonephritis patients without diabetes. METHODS: The anti-inflammatory effects of irbesartan were evaluated in 29 hypertensive chronic glomerulonephritis patients without diabetes in a prospective, single-arm study. RESULTS: Following treatment with irbesartan for 26 weeks, blood pressure and proteinuria significantly decreased, as previously reported (blood pressure decreased from 142±1/87±1 to 131±1/81±1 mmHg and the urine protein/creatinine ratio decreased from 1030±143 to 779±121 mg/g Cr). BMI did not significantly change after the study. Among the inflammatory parameters, the concentrations of adiponectin and high-sensitivity C-reactive protein (hsCRP) significantly improved after treatment; however, the changes in the concentrations of interleukin-6 (IL-6), tumor necrosis factor (TNF)-a and leptin did not reach statistical significance. Moreover, the changes in these five parameters following treatment were moderately correlated with the BMI values obtained at the initiation of the study, and the improvements were particularly prominent in those with a BMI greater than 25. Improvements in proteinuria were significantly correlated with increases in the adiponectin concentration, but not with BMI. There was also a moderate correlation between the changes in the adiponectin and insulin concentrations. CONCLUSION: Irbesartan improves metabolic parameters in nondiabetic hypertensive chronic glomerulonephritis patients, especially those with a high BMI. Improving the adiponectin concentration may be important for reducing proteinuria.