Andrographolide protects against radiation-induced lung injury in mice

Abstract

Objective To investigate the protective effect of andrographolide against radiation-induced lung injury (RILI) in C57BL/6 mice.Methods Eighty C57BL mice were randomly divided into four groups:un-irradiated and normal saline-treated group (n =20,control group),un-irradiated and andrographolide-treated group (n =20,drug group),radiation plus normal saline-treated group (n =20,radiation group) and radiation plus andrographolide-treated group (n =20,treatment group).Before radiation,the mice in drug group and treatment group were administered daily via gavage with andrographolide (20 mg· kg-1 · d-1)) for 30 d,while the same volume of normal saline solution was given daily in the control and radiation groups.The model of RILI in C57BL mice was established by irradiating whole mouse chest with a single dose of 15 Gy of 6 MV X-rays.The pathological changes of the lung stained with HE/Masson were observed with a light microscope.The transforming growth factor-β1 (TGF-β1) and tumor necrosis factor-α (TNF-α) in serum were examined by enzyme-linked immunosorbent assay.The activities of malondialdehyde (MDA) and superoxide dismutase (SOD) and the content of hydroxyproline in lung tissues were examined by corresponding kits.Results Compared with radiation group,there was an obvious amelioration in pathological injury of lung tissue in the treatment group.The lung coefficient,the activities of lung tissue MDA,the content of Hyp,the serum content of hydroxide free radical,and the serum levels of TGF-β1 and TNF-α in the treatment group were significantly lower than those in radiation group at 24th week,(tlungcoefficient =1.60,tMDA =7.06,tHyp =17.44,tTGF-β1 =16.67,tTNF-α =14.03,P ＜ 0.05),while slightly higher than those in control group.The activity of SOD was significantly higher in the treatment group than that in radiation group (t =60.81,P ＜ 0.05),while lower than those in control group and drug group.There were no significant differences in these indicators between control group and drug group.Conclusions Andrographolide effectively alleviates the RILI in mice by its antioxidant properties and the effects of downregulating the expressions of inflammatory factors and andrographolide-related lung-toxicity are not significant. Key words: Andrographolide; Radiation-induced lung injury ; Mice