Effectiveness of etanercept in bleomycin-induced experimental scleroderma

Objectives. To evaluate the effects of etanercept and thalidomide in the mouse model of bleomycin-induced scleroderma (BLM-IS).Methods. This study involved four groups (n = 8 mice in each group). Dermal sclerosis was induced by repeated subcutaneous injections of BLM (10 μg) for 4 weeks in BALB/c mice. Control group received only phosphate-buffered saline. The second group received only BLM; the third and fourth groups were also given an intraperitoneal injection of 100 μg etanercept or 150 mg/kg thalidomide, respectively.Results. BLM increased serum TGF-β 1 , tissue hydroxyproline levels and expression of α-smooth muscle actin (α-SMA), and dermal fibrosis was histopathologically prominent. Although thalidomide had no significant effect, etanercept caused decreases in levels of serum TGF-β 1 , tissue hydroxyproline and number of α-SMA-positive cells.Conclusion. Inhibition of TNF-α with etanercept in BLM-IS was resulted in a significant reduction of the dermal sclerosis, collagen accumulation and the number of infiltrating myofibroblastic cells. TNF-α may play a key role in the progression of BLM-IS and TNF-α antagonists may be useful in the management of scleroderma.