PI3K/AKT/mTOR, NF-κB and ERS pathway participated in the attenuation of H 2 O 2 -induced IPEC-J2 cell injury by koumine.

ETHNOPHARMACOLOGICAL RELEVANCE: Koumine, an indole alkaloid extracted from Gelsemium elegans Benth, exerts anti-inflammation and antioxidant activities. However, the effects of koumine on intestinal injury induced by H2 O2 and its potential molecular mechanisms need larger studies.

AIM OF THE STUDY: We established an IPEC-J2 cell damage model induced by H2 O2 to explore the protective mechanism of koumine on intestinal injury.

MATERIALS AND METHODS: In the experiment, cell damage models were made with hydrogen peroxide. To assess the protective effect of koumine on H2 O2 -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 H2 O2 -trigged IPEC-J2 cell damage.

RESULTS: The results of CCK-8 and LDH implied that koumine has a mitigative effect on H2 O2 -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 H2 O2 . Moreover, koumine dramatically attenuated H2 O2 -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 H2 O2 -stimulated IPEC-J2 cell inflammation.

CONCLUSIONS: This in vitro experimental study suggests that koumine suppresses the H2 O2 -induced activation of inflammatory pathways, oxidative injury, ER stress, apoptosis and autophagy, which provide a rationale for therapeutically use in major intestinal diseases.