Aspartate Metabolism-Driven Gut Microbiota Dynamics and RIP-Dependent Mitochondrial Function Counteract Oxidative...

Aspartate (Asp) metabolism-mediated antioxidant functions have important implications for neonatal growth and intestinal health; however, the antioxidant mechanisms through which Asp regulates the gut microbiota and influences RIP activation remain elusive. This study reports that chronic oxidative stress disrupts gut microbiota and metabolite balance and that such imbalance is intricately tied to the perturbation of Asp metabolism. Under normal conditions, in vivo and in vitro studies reveal that exogenous Asp improves intestinal health by regulating epithelial cell proliferation, nutrient uptake, and apoptosis. During oxidative stress, Asp reduces Megasphaera abundance while increasing Ruminococcaceae. This reversal effect depends on the enhanced production of the antioxidant eicosapentaenoic acid mediated through Asp metabolism and microbiota. Mechanistically, the application of exogenous Asp orchestrates the antioxidant responses in enterocytes via the modulation of the RIP3-MLKL and RIP1-Nrf2-NF-κB pathways to eliminate excessive reactive oxygen species and maintain mitochondrial functionality and cellular survival. These results demonstrate that Asp signaling alleviates oxidative stress by dynamically modulating the gut microbiota and RIP-dependent mitochondrial function, providing a potential therapeutic strategy for oxidative stress disease treatment.