Telmisartan alone or in combination with etanercept improves anemia associated with rheumatoid arthritis in rats: a possible role of anti-inflammatory and reno-protective effects.

Background: There are conflicting data regarding angiotensin receptor blockers (ARBs) induced anemia and its beneficial anti-inflammatory effect in rheumatoid arthritis. The aim of the present study was to investigate the effect of telmisartan administration either alone or in combination with etanercept on anemia of chronic inflammatory diseases in a model of rheumatoid arthritis in rats.

Methods: Rheumatoid arthritis (RA) was induced by Freund's Complete Adjuvant (FCA; 1 mg/0.1 ml paraffin oil), injected subcutaneously on days 0, 30 and 40. Rats with RA received dimethyl sulfoxide (DMSO), etanercept (0.3 mg/kg 3 times/week; sc), telmisartan (1.5 mg/kg/day; orally) or combination of etanercept and telmisartan. Arthritis parameters (footpad circumference change and paw volume change), erythrocyte indices (hemoglobin, mean corpuscular volume and mean corpuscular hemoglobin level changes), iron profile (serum iron and serum ferritin), serum levels of erythropoietin (EPO), hepcidin, tumor necrosis factor-alpha (TNF-α) and interleukin (IL)-6 were evaluated, along with measuring serum urea and creatinine levels.

Results: All treated groups showed improvement of the measured parameters in comparison to RA-control subgroup. Telmisartan either alone or in combination with etanercept significantly improved arthritis and erythrocyte indices. Telmisartan showed significant increase in EPO and decrease in hepcidin compared to etanercept. Combination group showed significant improvement in serum iron, ferritin, EPO, hepcidin, TNF-α, IL-6, urea and creatinine, compared to etanercept. Telmisartan either alone or in combination, but not etanercept alone, significantly decreased creatinine level.

Conclusion: Telmisartan improved anemia and arthritis parameters and showed anti-inflammatory and reno-protective effects, in a rat model of rheumatoid arthritis.