Glutamic acid(Glu)and aspartic acid(Asp)are acidic amino acids with regulatory roles in nutrition,energy metabolism,and oxidative stress.This study aimed to evaluate the effects of low-protein diets supplemented with Glu and Asp on the intestinal barrier function and energy metabolism in weaned piglets challenged with hydrogen peroxide(H2O2).Forty piglets were randomly divided into 5 groups:NC,PC,PGA,PG,and PA(n=8 for each group).Pigs in the NC and PC groups were fed a low-protein diet,while pigs in the PGA,PG,or PA groups were fed the low-protein diet supplemented with 2.0%Glu+1.0%Asp,2.0%Glu,or 1.0%Asp,respectively.On day 8 and 11,pigs in the NC group were intraperitoneally injected with saline(1 mL/kg BW),while pigs in the other groups were intraperitoneally administered 10%H2O2(1 mL/kg BW).On day 14,all pigs were sacrificed to collect jejunum and ileum following the blood sample collection in the morning.Notably,low-protein diets supplemented with Glu or Asp ameliorated the intestinal oxidative stress response in H2O2-challenged piglets by decreasing intestinal expression of genes(P<0.05)(e.g.,manganese superoxide dismutase[MnSOD],glutathione peroxidase[Gpx]-1,and Gpx-4)encoding oxidative stress-associated proteins,reducing the serum concentration of diamine oxidase(P<0.05),and inhibiting apoptosis of the intestinal epithelium.Glu and Asp supple-mentation attenuated the upregulated expression of energy metabolism-associated genes(such as hexokinase and carnitine palmitoyltransferase-1)and the H2O2-induced activation of acetyl-coenzyme A carboxylase(ACC)in the jejunum and adenosine monophosphate-activated protein kinase-acetyl-ACC signaling in the ileum.Dietary Glu and Asp also ameliorated intestinal barrier damage as indicated by restored intestinal histology and morphology.In conclusion,low-protein diets supplemented with Glu and Asp protected against oxidative stress-induced intestinal dysfunction in piglets,suggesting that this approach could be used as a nutritional regulatory protectant against oxidative
