Protective Effect of Lacticaseibacillus casei CRL 431 Postbiotics on Mitochondrial Function and Oxidative Status in Rats with Aflatoxin B 1 –Induced Oxidative Stress

Studies have shown that the intracellular content of probiotic (postbiotics) has antioxidant properties, which can improve the antioxidant status in vivo. However, its absorption and mechanisms underlying the protective effects are still unknown. The antioxidant capacity of Lacticaseibacillus casei CRL431 (IC-431) postbiotics was determined after an in vitro simulated digestive process. Permeability of antioxidant constituents of IC-431 was determined by an ex vivo everted duodenum assay. Aflatoxin B 1 –induced oxidative stress rat models were established and treated with IC-431; biomarkers of hepatic mitochondrial function and H 2 O 2 levels, oxidative stress, and oxidative stress index (OSi) were examined. The antioxidant capacity of IC-431 (477 ± 45.25 μmol Trolox Equivalent/L) was reduced by exposure to the simulated digestive process. No difference ( p > 0.05) was found among digested and the permeate fraction of IC-431. A protective effect was observed by significantly lower OSi and higher liver glutathione peroxidase and catalase activities. Lower H 2 O 2 production, a higher degree of mitochondrial uncoupling, and lower mitochondrial respiration coefficient were also observed ( p < 0.05). These results suggest that IC-431 antioxidant components permeate intestinal barriers to enter the bloodstream and regulate antioxidant status during AFB 1 -induced oxidative stress by reducing hepatic mitochondrial dysfunction, thus enhancing antioxidant enzyme response.