The Role and Mechanism of Retinol and Its Transformation Product, Retinoic Acid, in Modulating Oxidative Stress-Induced Damage to the Duck Intestinal Epithelial Barrier In Vitro

SIMPLE SUMMARY: In the intensive farming process of laying ducks, the intestinal tract is susceptible to oxidative stress, which results in the impairment of intestinal barrier function. This study investigated the effects of retinol and its transformation product, retinoic acid, on duck intestinal cells under oxidative stress. Cells were treated with different ratios of retinol and retinoic acid, and their viability, antioxidant capacity, and barrier function were assessed. The expression of genes related to oxidative stress and barrier function was measured. The results showed that treatment with different ratios of retinol and retinoic acid improved cell viability, antioxidant capacity, and barrier function. High retinoic acid treatment enhanced cell activity and barrier function by affecting certain pathways, while high retinol treatment promoted barrier repair through different pathways. This study highlights the roles of retinol and retinoic acid in protecting duck intestinal epithelial cells from oxidative stress and enhancing barrier function and provides insights into their underlying mechanisms. This understanding could contribute to developing strategies to mitigate oxidative damage and improve intestinal health. ABSTRACT: This study aimed to investigate the effects and mechanisms of retinol and retinoic acid on primary duck intestinal epithelial cells under oxidative stress induced by H(2)O(2). Different ratios of retinol and retinoic acid were used for treatment. The study evaluated the cell morphology, viability, antioxidative capacity, and barrier function of cells. The expression of genes related to oxidative stress and the intestinal barrier was analyzed. The main findings demonstrated that the treated duck intestinal epithelial cells exhibited increased viability, increased antioxidative capacity, and improved intestinal barrier function compared to the control group. High retinoic acid treatment improved viability and gene expression, while high retinol increased antioxidative indicators and promoted intestinal barrier repair. Transcriptome analysis revealed the effects of treatments on cytokine interactions, retinol metabolism, PPAR signaling, and cell adhesion. In conclusion, this study highlights the potential of retinol and retinoic acid in protecting and improving intestinal cell health under oxidative stress, providing valuable insights for future research.