Pyrrolidine dithiocarbamate restores gastric damages and suppressive autophagy induced by hydrogen peroxide

Abstract

It is well known that gastric barrier is very important for protecting host from various insults. Simultaneously, autophagy serving as a prominent cytoprotective and survival pathway under oxidative stress conditions is being increasingly recognized. Thus, this study was conducted for investigating the effect of pyrrolidine dithiocarbamate (PDTC) on gastric barrier function and autophagy under oxidative stress induced by intragastric administration of hydrogen peroxide (H₂O₂). The gastric tight junction proteins [zonula occludens-1 (ZO1), occludin, and claudin1], autophagic proteins [microtubule-associated protein light chain 3I(LC3I), LC3II, and beclin1], and nuclear factor kappa B (NF-κB) signaling pathway (p65 and IκB kinase α/β) were determined by Western blot. The results showed that H₂O₂ exposure disturbed gastric barrier function with decreased expression of ZO1, occludin, and claudin1, and reduced gastric autophagy with decreased conversion of LC3I into LC3II in mice. However, treatment with PDTC restored these adverse effects evidenced by increased expression of ZO1 and claudin1 and increased conversion of LC3I into LC3II. Meanwhile, H₂O₂ exposure decreased normal human gastric epithelial mucosa cell line (GES-1) viability in a concentration-dependent way. However, after being exposed to H₂O₂, GES-1 exhibited autophagic response which was inconsistent with our in vivo results in mice, while PDTC failed to decrease autophagy in GES-1 induced by H₂O₂. Simultaneously, the beneficial effect of PDTC on gastric damage and autophagy in mice might be independent of inhibition of NF-κB. In conclusion, PDTC treatment restores gastric damages and reduced autophagy induced by H₂O₂. Therefore, PDTC may serve as a potential adjuvant therapy for gastric damages.

Keywords::

• pyrrolidine dithiocarbamate
• oxidative stress
• hydrogen peroxide
• tight junction protein
• autophagy

Acknowledgments

This study was supported by the National Natural Science Foundation of China (NO. 31272463), the Hunan Provincial Natural Science Foundation of China (NO. 12JJ2014), and the Changsha science and technology key program (K1307007–21). The authors’ contributions were as follows: TJ.Li. and YL.Yin. conceived and designed the study. JL. Duan, J.Yin, and WK. Ren did the experiment and analyzed the data. JL. Duan wrote the manuscript and involved in the data analysis. WK. Ren, and MM. Wu revised the manuscript. All authors read and approved the final version of the manuscript.

Declaration of interest

The authors report no declarations of interest. The authors alone are responsible for the content and writing of the paper.