The predominant pathological processes of radiation-induced esophageal toxicity include inflammatory reactions in the early stage and the fibrotic process in the late stage. An increased expression of the epidermal growth factor (EGF) and transforming growth factor β1 (TGF-β1) is capable of reducing inflammatory reactions and TGF-β1 is considered responsible for the initiation, development and persistence of fibrosis. In the present study, we investigated in vivo the therapeutic effect of the compound of white peony root oral liquids (cWPROL) on reducing the toxicity via modulating the expression levels of EGF and TGF-β1. Adult male Wistar rats were treated and tissue sections were obtained. The tissue sections were stained using histological, Masson and immunohistochemical staining. The results revealed that cWPROL had a higher rate of repairing damaged structures compared with the control group. In addition, immunohistochemistry showed that although cWPROL and the mixture of lidocaine, dexamethasone and gentamycin (mLDG) induced levels of EGF and TGF-β1 expression, there were differences between the two types of intervention. These results are significant for understanding that the mechanism of therapeutic effect of cWPROL varied to some extent from that of mLDG.
Keywords: compound of White Peony Root Oral Liquid; epidermal growth factor; radiation-induced esophagitis; radiation-induced fibrosis; transforming growth factor β1.