Weifuchun Capsule Improves Acute Gastric Ulcer in Rats by Inhibiting AQP3 and Regulating Inflammatory Water Metabolism Disorder

OBJECTIVE To explain the intervention effect from the perspective of water metabolism of Weifuchun capsule(WFC) on gastric ulcers by observing the effect of WFC on the expression of inflammatory factors and aquaporins(AQPs) in rat gastric ulcer tissue, providing the experimental and theoretical basis for the clinical prevention and treatment of gastric ulcer with WFC. METHODS A total of 40 male SD rats weighing 190-210 g were randomly divided into the following 5 groups according to their body weight:sham operation group(normal saline), model group(normal saline), positive control group(ranitidine 30 mg·kg^-1), WFC high-dose group(1 000 mg·kg^-1) and WFC low-dose group(500 mg·kg^-1). Before modeling, rats in each group were given corresponding doses of drugs by oral gavage. After continuous administration for 3 d, acetic acid-induced gastric ulcer model surgery in rats was performed. After administration for successive 5 d, the rats were treated. The gastric juice was collected for detecting the amount of gastric juice and pepsin activity. The gastric tissue was taken for gross and histopathological observation. The levels of superoxide dismutase(SOD), malondialdehyde(MDA), and inflammatory factors in gastric tissue were detected, the expression of AQPs mRNA was detected by RT-PCR, and the expression of AQP3 protein was detected by immunofluorescence. The parietal cells of rats in each group were separated, and the confocal microscope was used to further confirm the expression level of AQP3 and the release of inflammatory factors. RESULTS Rats in the gastric ulcer model group had obvious gastric ulcers and erosions, accompanied by bleeding points; rats in the high- and low-dose groups of WFC had improved gastric mucosal ulcers and erosions to varying degrees. According to histopathology, the model group showed mucosal edema and erosion, inflammatory cell infiltration, destruction of lamina propria glands, and mesenchymal congestion; different dose groups of WFC had a significant improvement effect on the characteristic lesions of gastric ulcer. The pepsin activity in the model group was significantly increased, which was decreased in the high- and low-dose groups and in the positive control group. In addition, WFC could significantly reduce the secretion of gastric juice in rats with gastric ulcers, inhibit the activity of pepsin, increase the activity of gastric antioxidant enzymes, and reduce the level of serum inflammatory factors. The RT-PCR and immunofluorescence results showed that WFC capsules had a significant regulatory effect on the expression of AQP3 mRNA and protein in gastric ulcer tissues. The gastric parietal cells were further isolated, and it was confirmed that WFC capsules had a significant inhibitory effect on the expression of AQP3 in parietal cells. CONCLUSION WFC capsule can significantly improve the symptoms of gastric ulcers in rats, increase the body's antioxidant level, and regulate inflammatory water metabolism disorders. Its mechanism of action may be related to the inhibition of AQP3 expression in gastric parietal cells.