Mitigation of oxidative stress in chicken intestinal epithelial cells by functional nutrients

This study aimed to identify functional nutrients that enhance barrier function of chicken intestinal epithelial cells and alleviate stress in chickens by evaluating the effects of six candidate materials: threonine, arginine, vitamin C, vitamin E, chromium, and zinc. Each treatment group was treated with 2, 20, and 200 μg/mL. Among these, vitamin C and zinc demonstrated superior effects on chicken intestinal epithelial cell proliferation. Arginine and zinc effectively reduced (<italic>p</italic> &lt; 0.05) heat stress-related “heat shock protein 70” levels. However, none of the tested materials significantly impacted oxidative stress markers, such as nitric oxide and reactive oxygen species. Notably, vitamin C and zinc increased (<italic>p</italic> &lt; 0.05) transepithelial electrical resistance and decreased (<italic>p</italic> &lt; 0.05) fluorescein isothiocyanate–dextran permeability, indicating their positive impact on barrier function of chicken intestinal epithelial cells. Additionally, threonine evidently promoted tight junction health during prolonged treatment. These findings suggest that <span style="text-decoration:underline;">threonine, vitamin C, and zinc</span> help upregulate proteins associated with tight junction integrity. Taken together, <span style="text-decoration:underline;">amino acids, vitamin C, and zinc</span> display promise as functional nutrients for enhancing intestinal barrier function and mitigating stress damage in chickens.