Protective Effect of Xiangsha Yuyang Decoction on Oxidative Injury in Rats with Gastric Ulcer Based on p62/Keap1/Nrf2 Signal Pathway / 中国实验方剂学杂志

ABSTRACT

Objective:To confirm the protective effect of Xiangsha Yuyang decoction on acetic acid-induced gastric ulcer model rats and explore its mechanism， so as to provide experimental basis for clinical drug use. Method:The 60 SPF Wistar rats were randomly divided into 6 groups： group， model group， high， middle and low dose groups of Xiangsha Yuyang decoction and omeprazole control group. The rat model of gastric ulcer was induced by acetic acid. The rats in the high， middle and low dose groups of Xiangsha Yuyang decoction were intragastrically administered at the dose of 28，14，7 g·kg^-1， and with omeprazole at the dose of 4.17 g·kg^-1in normal saline， respectively. The rats in the blank group and model group were intragastrically infused with the same volume of normal saline once a day. After 14 days of continuous treatment， the rats were killed， the blood was collected， the area and inhibition rate of gastric ulcer were measured and calculated， the histopathological sections of gastric mucosa were made and the state of gastric mucosal injury was observed， and the changes of gastric mucosal repair factor， gastric tissue related protein， oxidative stress factor and inflammatory factor in serum were detected by enzyme-linked immunosorbent assay（ELISA）. Detected the expression of p62 Kelch-like epichlorohydrin-related protein 1 （Keap1）， nuclear transcription factor E2 related factor 2 （Nrf2） and heme oxygenase-1 （HO-1） signal pathway-related proteins in gastric mucosa by Western blot. Result:Compared with control group， the gastric mucosa of the model group showed obvious pathological changes and a large number of leukocytes infiltrated. In model group， the ulcer area was significantly increased（<italic>P</italic><0.01）， the contents of mucin mucoprotein 5AC （MUC5AC）， epidermal growth factor （EGF）， superoxide dismutase （SOD） and increased prostaglandin E₂ （PGE₂） were significantly decreased（<italic>P</italic><0.01）， the gastrin （GAS）， 8-hydroxydeoxyguanosine （8-OHdG）， malondialdehyde （MDA）， tumor necrosis factor-<italic>α</italic> （TNF-<italic>α</italic>）， cyclooxygenase-2 （COX-2） were significantly increased. The expression of HO-1 and Nrf2 protein decreased significantly（<italic>P</italic><0.01）， the content of Keap1 increased significantly （<italic>P</italic><0.05）， and the expression of p62 protein decreased. Compared with model group， the hierarchical structure of cells in Xiangsha Yuyang decoction high dose group and omeprazole group were clearer and regular， middle and low dose groups could also repair gastric mucosa to a certain extent. The high and middle dose groups of Xiangsha Yuyang decoction could significantly reduce the gastric ulcer area of acetic acid-induced gastric ulcer rat model （<italic>P</italic><0.01） and increase the ulcer inhibition rate. It can effectively promote the expression of MUC5AC and EGF in gastric mucosa， decrease the level of GAS（<italic>P</italic><0.05，<italic>P</italic><0.01）， decrease the level of 8-OHdG and MDA， increase the activity of SOD（<italic>P</italic><0.01）， decrease the expression level of TNF-<italic>α</italic> and COX-2， increase the content of PGE₂， and significantly increase the amount of Nrf2 and HO-1 protein in gastric mucosa（<italic>P</italic><0.01）. The high dose group of Xiangsha Yuyang decoction could decrease the protein expression of Keap1（<italic>P</italic><0.05） and increase the expression of p62 protein. Conclusion:Xiangsha Yuyang decoction is effective in the treatment of acetic acid-induced gastric ulcer model rats， which can effectively reduce the ulcer area， increase the ulcer inhibition rate and protect the ulcer tissue. Its mechanism may be related to activating p62/Keap1/Nrf2 signal pathway and regulating the expression of related genes so as to improve inflammatory response and regulate oxidative stress response.