Zearalenone Induces Apoptosis in Porcine Endometrial Stromal Cells through JNK Signaling Pathway Based on Endoplasmic Reticulum Stress

Abstract

Zearalenone (ZEA) is an estrogen-like mycotoxin characterized mainly by reproductive toxicity, to which pigs are particularly sensitive. The aim of this study was to investigate the molecular mechanism of ZEA-induced apoptosis in porcine endometrial stromal cells (ESCs) by activating the JNK signaling pathway through endoplasmic reticulum stress (ERS). In this study, ESCs were exposed to ZEA, with the ERS inhibitor sodium 4-Phenylbutyrate (4-PBA) as a reference. The results showed that ZEA could damage cell structures, induce endoplasmic reticulum swelling and fragmentation, and decreased the ratio of live cells to dead cells significantly. In addition, ZEA could increase reactive oxygen species and Ca2+ levels; upregulate the expression of GRP78, CHOP, PERK, ASK1 and JNK; activate JNK phosphorylation and its high expression in the nucleus; upregulate the expression Caspase 3 and Caspase 9; and increase the Bax/Bcl-2 ratio, resulting in increased apoptosis. After 3 h of 4-PBA-pretreatment, ZEA was added for mixed culture, which showed that the inhibition of ERS could reduce the cytotoxicity of ZEA toward ESCs. Compared with the ZEA group, ERS inhibition increased cell viability; downregulated the expression of GRP78, CHOP, PERK, ASK1 and JNK; and decreased the nuclear level of p-JNK. The Bax/Bcl-2 ratio and the expression of Caspase 3 and Caspase 9 were downregulated, significantly alleviating apoptosis. These results demonstrate that ZEA can alter the morphology of ESCs, destroy their ultrastructure, and activate the JNK signaling via the ERS pathway, leading to apoptosis.

Combination of Zearalenone and Deoxynivalenol Induces Apoptosis by Mitochondrial Pathway in Piglet Sertoli Cells: Role of Endoplasmic Reticulum Stress

“…In SiHa cells, Trichomonas vaginalis triggers ERS-induced mitochondrial apoptosis through the IRE1/ASK1/JNK/ Bcl-2 family protein pathways [ 39 ]. Our previous research indicates that adding 4-PBA can alleviate toxic damage and apoptosis in porcine germ cells and alleviate ERS caused by ZEA [ 14 , 40 ]. Bcl-2 family proteins play a critical role in regulating the release of apoptotic factors related to mitochondria, which are mainly divided into pro-apoptotic factors and anti-apoptotic factors.…”

“…The cell viability was observed using a fluorescence optical microscope. Further details can be found in a previous study conducted by our laboratory [ 40 ].…”

“…After culturing the cells in 24-well plates for 24 h, the cells were treated with Calcein AM/PI working solution for 30 min at 37 • C. The cell viability was observed using a fluorescence optical microscope. Further details can be found in a previous study conducted by our laboratory [40].…”

Fusarium mycotoxins: The major food contaminants

“…At high concentrations, ZEA causes mitochondrial dysfunction, EnR stress, apoptosis, and autophagy. ZEA reduces the protein expression of Nrf2 and HO‐1 to further induce oxidative stress and cause cell apoptosis via the p38, JNK, and ERK MAPK pathways 63 , 64 , 65 . Bai et al found that ZEA can induce apoptosis by modulating EnR stress though the PERK and ATF6 signaling pathways in porcine trophectoderm cells 66 .…”

Inhibition of Mitochondrial Fission Alleviates Zearalenone-Induced Mitochondria-Associated Endoplasmic Reticulum Membrane Dysfunction in Piglet Sertoli Cells

“…The cells were collected and subjected to FACS Calibur flow cytometry (BD, Franklin Lakes, NJ, USA) to detect their Ca 2+ fluorescence intensity. For the details, see our laboratory's previous study [32].…”