Ethnopharmacological relevanceKoumine, an indole alkaloid extracted from Gelsemium elegans Benth, exerts anti-inflammation and antioxidant activities. However, the effects of koumine on intestinal injury induced by H2O2 and its potential molecular mechanisms need larger studies.Aim of the study: We established an IPEC-J2 cell damage model induced by H2O2 to explore the protective mechanism of koumine on intestinal injury. Materials and methodsIn the experiment, cell damage models were made with hydrogen peroxide. To assess the protective effect of koumine on H2O2-induced IPEC-J2 cell injury, CCK-8, the release of LDH and ROS, transmission electron microscopy and Annexin V-FITC/PI were employed. Western Blot and Quantitative Real-time PCR were used to determine the potential alleviated mechanism of koumine on H2O2-trigged IPEC-J2 cell damage. ResultsThe results of CCK-8 and LDH implied that koumine has a mitigative effect on H2O2-induced cell damage via upregulating cell viability and suppressing cell membrane fragmentation. Simultaneously, koumine notably inhibited the level of pro-inflammatory factors (IL-1β, IL-6, IL-8, TNF-α and TGF-β), the over-production of ROS along with decreasing the injury of mitochondrion, endoplasmic reticulum and lysosome induced by H2O2. Moreover, koumine dramatically attenuated H2O2-triggered IPEC-J2 cell apoptosis and autophagy. Subsequently, Western blot analysis identified NF-ΚB, PI3K and ERS as possible pathway responsible for the protective effect of koumine on H2O2-stimulated IPEC-J2 cell inflammation. ConclusionsThis in vitro experimental study suggests that koumine suppresses the H2O2-induced activation of inflammatory pathways, oxidative injury, ER stress, apoptosis and autophagy, which provide a rationale for therapeutically use in major intestinal diseases.