Dioscorea oppositifolia L. Attenuates Weaning-Induced Intestinal Injury by Regulating Oxidative Stress and Apoptosis in Piglets

Weaning stress is frequently associated with intestinal oxidative stress, inflammatory activation, and epithelial apoptosis in piglets. This study investigated whether dietary supplementation with Chinese yam (Dioscorea oppositifolia L., YAM) alleviates weaning-induced intestinal injury by modulating the oxidative stress-inflammation-apoptosis axis. 48 weaned piglets were assigned to a control diet or diets supplemented with low (1%)/high (2%) doses of YAM. Intestinal morphology, antioxidant capacity, inflammatory signaling, and apoptosis-related markers were assessed, and jejunal transcriptomic profiling was also performed. Supplementing with YAM improved villus architecture and enhanced intestinal antioxidant properties, manifested as increased total antioxidant capacity and reduced malondialdehyde levels. At the molecular level, YAM activated the Keap-1/Nrf2/HO-1 pathway and upregulated the expression of antioxidant-related genes, including superoxide dismutase 2 (SOD2), catalase (CAT), and NAD(P)H quinone dehydrogenase 1 (NQO1), and suppressed NF-κB signaling by reducing Myd88 and p-p65 protein levels. In addition, YAM modulated mitochondrial apoptosis by upregulating Bcl-2 and reducing the expression of Bax and Cleaved caspase-3. Transcriptomic analysis identified 1227 differentially expressed genes between the control and high-dose groups (784 upregulated and 443 downregulated). Mechanism-oriented module analysis further confirmed coordinated enhancement of antioxidant pathways alongside suppression of inflammatory and apoptotic gene signatures. These findings demonstrate that dietary YAM supplementation attenuates weaning-associated intestinal injury by rebalancing oxidative stress, inflammatory signaling, and apoptosis-related pathways, thereby supporting its potential application as a functional feed additive in swine production.