Study on the Protective Effect of the Dunhuang Medical Formula Dabupi Decoction on Rats with Radiation-induced Intestinal Edema

OBJECTIVE To investigate the protective effect and possible mechanism of Dunhuang medical formula Dabupi decoction on radiation-induced intestinal edema, and to provide experimental basis for the protection of clinical radiation-induced intestinal edema and the promotion of Dunhuang medical formula.

METHODS  SD rats were divided into three groups, blank control group, model group and experimental group, the model group was irradiated whole body by 6 Gy X-ray, and the experimental group was given Dabupi decoction 6.8 g·kg⁻¹ by gavage 14 d before irradiation. The general conditions of rats were observed; morphological changes of colon tissues were observed by HE staining; ultrastructural changes of colon tissues were detected by transmission electron microscopy; the expression levels of ROS, hypoxia inducible factor 1 alpha(HIF-1α) and aquaporin(AQP4) in colon tissues were detected by immunofluorescence; and the expression levels of HIF-1α, AQP4, heme oxidized IRP2 ubiquitin ligase 1 like(HOIL-1L), protein kinase C zeta(PKCζ), Occludin and Na⁺/K⁺-ATPase protein were detected by Western blotting.

RESULTS Compared with the blank control group, the colon tissues of rats in the model group showed mucosal necrosis and detachment, mucosal and submucosal oedema, and the ultrastructure of the colon showed swollen cytoplasmic matrix, swollen and deformed mitochondria, dilated to form vacuolisation, significantly higher fluorescence expression of ROS, HIF-1α and AQP4(P<0.05 or P<0.01), HIF-1α, AQP4 and HOIL-1L protein expression was significantly higher(P<0.01), while PKCζ, Occludin and Na⁺/K⁺-ATPase protein expression was significantly lower(P<0.01). Compared with the model group, the experimental group showed reduced mucosal detachment and oedema in colonic tissues, significantly better swelling of colonic mitochondria, significantly improved large intracytoplasmic vacuoles, significantly lower fluorescence expression of ROS, HIF-1α, and AQP4(P<0.05 or P<0.01), and significantly decreased protein expression of HIF-1α, AQP4, and HOIL-1L(P<0.01), while significantly increased protein expression of PKCζ, Occludin and Na⁺/K⁺-ATPase(P<0.01).

CONCLUSION The Dunhuang medical formula Dabupi decoction can effectively protect radiation-induced intestinal edema, and the mechanism may work by inhibiting the expression of ROS, HIF-1α and AQP4 and promoting the expression of PKCζ, Na⁺/K⁺-ATPase and Occludin.