The change of TGF-β_1 expression in lung tissue of type 2 diabetic rats and the effect of rosiglitazone on TGF-β1 expression

Objective To observe the changes of TGF-β1 in lung tissue of diabetic rats,and to investigate the effect and action mechanism of rosiglitazone on pulmonary fibrosis in diabetic rats.Methods The experimental type 2 diabetic rats models were established by injecting streptozotocin (STZ) and feeding high fat and glucose food,then the changes of morphology in the lung of the rats were examined by light microscope in control group,diabetes group and rosiglitazone intervention group on the 12th week and the 24th week respectively,and the collagen accumulation in lung was detected by masson trichrome staining and the changes of TGF-β1 in lung were detected by immunohistochemistry.Results The amount of collagen fiber was increased obviously in lung tissue of diabetic rats,so was the expression of TGF-β1.Rosiglitazone decreased the levels of TGF-β1 in lung tissue.Conclusion There is pulmonary fibrosis in diabetic rats.The levels of TGF-β1 are increased in lung tissue of diabtetic rats,which may be related to lung tissue pathological changes in the diabetic rats.Rosiglitazone may relieve the pulmonary fibrosis by down-regulating the levels of TGF-β1.