RESUMO
Objective To investigate the effect of matrine on gastric mucosal injury induced by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) in rats and its mechanism. Methods A total of 75 Wister rats were randomly divided into a control group, a model group and three matrine-treated groups (100, 150 and 200 mg/kg). Except for the control group, the other groups were treated with MNNG to establish the models of gastric mucosal injury in the rats. After the models were successfully established, the rats in the three matrine-treated groups were administrated 100, 150, 200 mg/kg matrine, respectively, for successive 45 days. After the last administration, the body mass, daily intake of drinking water and dietary of rats were measured. And then the tissue samples were collected after the rats were sacrificed. The levels of interleukin 1ß (IL-1ß), IL-4, interferon gamma (IFN-γ), and tumor necrosis factor alpha (TNF-α) were measured by ELISA in gastric mucosa. HE staining was used to observe the pathological changes of gastric mucosa tissue. Immunohistochemical staining was performed to evaluate the expression of vascular endothelial growth factor C (VEGF-C) and vascular endothelial growth factor receptor 3 (VEGFR3) in gastric mucosa. The protein levels of Bcl2, BAX, caspase-3, cytochrome C (Cyt-C), Toll-like receptor 4 (TLR4), myeloid differentiation factor 88 (MyD88) and nuclear factor κB p65 (NF-κB p65) were determined by Western blotting. Results The body mass, daily intake of drinking water and dietary increased in matrine-treated rats in comparison with the model group. In addition, compared with the model group, matrine significantly reduced the expression levels of VEGF-C, VEGFR3, BAX, caspase-3, Cyt-C, TLR4, MyD88 and NF-κB p65, and increase Bcl2 protein level in the gastric mucosa tissues. Conclusion Matrine can reduce gastric mucosal damage induced by MNNG in rats, which is related to the down-regulation of VEGF-C/VEGFR3 and NF-κB/TLR4 signaling pathway.