Atractylenolide III ameliorated reflux esophagitis via PI3K/AKT/ NF-κB/iNOS pathway in rats

Reflux esophagitis (RE), an esophageal inflammation caused by reflux of gastric contents, often damages the lower esophagus, seriously affecting the quality of life of patients. This study aims to investigate the therapeutic effects and underlying molecular mechanisms of atractylenolide III (ATL III) on RE model rats. In this research, the RE rat model is established sequentially following hemipyloric ligation, cardia transection, and hydrochloric acid perfusion. Further, the RE-induced rats are intragastrically administrated with ATL III (0.6, 1.2, and 2.4 mg/kg/D) for 28 days to evaluate ATL III therapeutic effects. To study the molecular mechanism, RE rats are treated with a phosphoinositide-3 kinase (PI3K) agonist (740 Y-P) combined with ATL III. The histopathological changes in the esophagus are eventually observed by hematoxylin & eosin (H&E) staining. In addition to changes in gastric pH and levels of reactive oxygen species (ROS), enzyme-linked immunosorbent assay (ELISA) and Western blot analyses are used to detect the expression levels of tumor necrosis factor-alpha (TNF-alpha, mmol/L), interleukin (IL)-8, IL-6, IL-1 beta in the esophageal tissues. As a result, the lesions in the esophageal tissues of RE rats are alleviated, decreasing the macroscopic observation scores of the esophageal mucosa after ATL III treatment,. The experi-mental results indicated significantly increased pH value of the gastric contents and reduced ROS, thiobarbituric acid reactants (TBARS), TNF-alpha, IL-8, IL-6, and IL-1 beta levels, as well as expression levels of p-PI3K, p-AKT, iNOS, and nuclear NF-kappa B proteins in esophageal tissues. In conclusion, the study indicated that ATL III could efficiently treat RE in rats by inhibiting oxidative stress and inflammatory damage through the PI3K/AKT/NF-kappa B/iNOS pathway.