Autophagy protects intestinal epithelial cells against deoxynivalenol toxicity by alleviating oxidative stress via IKK signaling pathway.

Abstract

Autophagy is an intracellular process of homeostatic degradation that promotes cell survival under various stressors. Deoxynivalenol (DON), a fungal toxin, often causes diarrhea and disturbs the homeostasis of the intestinal system. To investigate the function of intestinal autophagy in response to DON and associated mechanisms, we firstly knocked out ATG5 (autophagy-related gene 5) in porcine intestinal epithelial cells (IPEC-J2) using CRISPR-Cas9 technology. When treated with DON, autophagy was induced in IPEC-J2 cells but not in IPEC-J2.Atg5ko cells. The deficiency in autophagy increased DON-induced apoptosis in IPEC-J2.atg5ko cells, in part, through the generation of reactive oxygen species (ROS). The cellular stress response can be restored in IPEC-J2.atg5ko cells by overexpressing proteins involved in protein folding. Interestingly, we found that autophagy deficiency downregulated the expression of endoplasmic reticulum folding proteins BiP and PDI when IPEC-J2.atg5ko cells were treated with DON. In addition, we investigated the molecular mechanism of autophagy involved in the IKK, AMPK, and mTOR signaling pathway and found that Bay-117082 and Compound C, specific inhibitors for IKK and AMPK, respectively, inhibited the induction of autophagy. Taken together, our results suggest that autophagy is pivotal for protection against DON in pig intestinal cells.

• Authors: Yulong Tang, Jianjun Li, Fengna Li, Chien-An A Hu, Peng Liao, Kunrong Tan, Bie Tan, Xia Xiong, Gang Liu, Tiejun Li, Yulong Yin
• Journal: Free radical biology & medicine (Free Radic Biol Med) Vol. 89 Pg. 944-51 (Dec 2015) ISSN: 1873-4596 [Electronic] United States
• PMID: 26456059 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2015 Elsevier Inc. All rights reserved.

Chemical References

• Trichothecenes
• I-kappa B Kinase
• deoxynivalenol

Topics

• Animals
• Apoptosis (drug effects)
• Autophagy (drug effects)
• Blotting, Western
• Cell Proliferation
• Cells, Cultured
• Epithelial Cells (drug effects, metabolism, pathology)
• Flow Cytometry
• I-kappa B Kinase (metabolism)
• Intestinal Mucosa (metabolism)
• Intestines (drug effects, pathology)
• Oxidative Stress (drug effects)
• Signal Transduction (drug effects)
• Swine
• Trichothecenes (toxicity)