Abstract: Objective: The purpose of this study was to clarify the protective effect of foxtail millet bran polyphenols on alcohol-induced gastric mucosal injury and its underlying molecular mechanism in order to provide a scientific basis for the application of foxtail millet bran polyphenols in nutritional intervention for patients with alcohol-induced gastric mucosal injury. Methods: Male Wistar rats were intragastrically administered with 50 mg/kg mb of polyphenols derived from foxtail millet bran on a daily basis for three successive weeks. Afterwards, a rat model of acute alcohol-induced gastric mucosa injury was established by intragastrically administering the animals with 75% ethanol solution. Alcohol-induced gastric epithelial cell injury and intervention models were established by sequential treamtment of human gastric epithelial cells (GES-1 cells) with different doses (1–15 μg/mL) of foxtail millet bran polyphenols for 24 h followed by 1 000 mmol/L of ethanol for 12 h. The morphological and pathological structure of rat stomach was observed by dissection, and the protective effect of foxtail millet bran polyphenols on rat gastric mucosa was evaluated. The protective effect of foxtail millet bran polyphenols on GES-1 cells was evaluated in combination with cell morphological changes and survival rates. Finally, oxidative stress and apoptosis indicators were measured to evaluate the effects of foxtail millet bran polyphenols on antioxidant activity in rats and GES-1 cells with acute alcohol-induced injury and the inhibitory effect of foxtail millet bran polyphenols on ethanol-induced cell apoptosis. Results: Foxtail millet bran-derived polyphenols could effectively prevent alcohol-induced rat gastric mucosal and GES-1 cell injury, significantly attenuate the ethanol-induced increase in the levels of reactive oxygen species (ROS) in GES-1 cells (P < 0.01). At the same time, it significantly relieved the elevated level of malondialdehyde (MDA) in rat gastric mucosal and markedly enhanced the activity of superoxide dismutase (SOD), and obviously inhibited ethanol-induced cell apoptosis. Conclusion: Foxtail millet bran-derived polyphenols protect the gastric mucosa by alleviating ethanol-induced oxidative damage of gastrointestinal mucosal epithelial cells.

Key words: foxtail millet bran; polyphenols; ethanol; gastric mucosal damage; oxidative damage