Exhibits Antioxidant and Cytoprotective Activities in Porcine Intestinal Epithelial Cells Exposed to Hydrogen Peroxide.

Probiotics are widely used for protection against stress-induced intestinal dysfunction. Oxidative stress plays a critical role in gastrointestinal disorders. It is established that probiotics alleviate oxidative stress; however, the mechanism of action has not been elucidated. We developed an intestinal porcine epithelial cells (IPEC-J2) model of oxidative stress to explore the antioxidant effect and potential mode of action of ZLP001. The IPEC-J2 cells were preincubated with and without ZLP001 for 3 h and then exposed to hydrogen peroxide (HO) for 4 h. Pretreatment with ZLP001 protected IPEC-J2 cells against HO-induced oxidative damage as indicated by cell viability assays and significantly alleviated apoptosis elicited by HO. ZLP001 pretreatment decreased reactive oxygen species production and the cellular malondialdehyde concentration and increased the mitochondrial membrane potential compared with HO treatment alone, suggesting that ZLP001 promotes the maintenance of redox homeostasis in the cells. Furthermore, ZLP001 regulated the expression and generation of some antioxidant enzymes, thereby activating the antioxidant defense system. Treatment with ZLP001 led to nuclear erythroid 2-related factor 2 (Nrf2) enrichment in the nucleus compared with HO treatment alone. Knockdown of Nrf2 significantly weakened the alleviating effect of ZLP001 on antioxidant stress in IPEC-J2 cells, suggesting that Nrf2 is involved in the antioxidative effect of ZLP001. Collectively, these results indicate that ZLP001 is a promising probiotic bacterium that can potentially alleviate oxidative stress.