Effectiveness of ghrelin treatment in Bleomycin-induced experimental scleroderma

Scleroderma is a chronic inflammatory disease characterized by widespread fibrosis of the skin and internal organs. Ghrelin is a polypeptide hormone that is produced by various tissues and inflammatory cells mainly from stomach (enteroendocrine cells). In experimental studies, ghrelin has been shown to have anti-inflammatory and antioxidant effects in addition to its metabolic functions.The aim of this study was to evaluate the possible preventive effects of ghrelin on bleomycin-induced experimental scleroderma model.This study involved five groups Balb/c mice (n=7 in each group). Group I mice only received subcutaneously 100 µl/day phosphate-buffered saline (PBS), whereas group II, III, IV and V mice were subcutaneously administrated 100 µg/day bleomycin (1 mg bleomycin dissolved in 1 mL PBS). In addition to bleomycin, group III, IV, V mice were received intraperitoneally acylated, non-acylated and total ghrelin, respectively at the doses of 10 ng/kg/day.Animals were sacrificed, at the end of fourth week, and blood and tissue samples were then obtained for further analysis. TGF-ß1 serum levels, dermal thicknesses, the numbers of inflammatory cells on the dermal layer and ?-smooth muscle actin-positive (?-SMA+) cells were determined.Bleomycin administrations increased dermal thicknesses, the numbers of inflammatory cells on the dermal layer and activity of myofibroblastic cells. When acylated, non-acylated and total ghrelin ghrelin were administrated together with bleomycin, skin fibrosis, infiltration of inflammatory cells and activity of myofibroblastic cells had not been observed.In conclucion, in bleomycin-induced experimental scleroderma model, ghrelin prevents skin fibrosis by its anti-inflammatory effects.Key Words: Scleroderma, Bleomycin, Ghrelin