Effects Of Zearalenone On Intestinal Mucosal Barrier In Mice And IPEC-J2 Cells

Zearalenone(ZEA),as a class of mycotoxins that exerts an estrogenic effect,which is a common environmental pollutant in cereal crops worldwide and it can cause serious damage to health of animals or human.In recent years,it has been reported that exposure to specific mycotoxins causes changes in intestinal function and induces chronic intestinal inflammation in humans.But we often overlook the toxic effects of ZEA on the intestinal mucosa.Therefore,in this study,mice and IPEC-J2 cells were used to study effects of ZEA on intestinal mucosal barrier.The aim is to reveal the potential mechanism of ZEA for mammalian or human intestinal health and provide a theoretical reference for the study of ZEA induced intestinal diseases.In vivo experiment,24 BALB/C mice of 4 weeks old were randomly divided into 2 groups.Each group had 3 replicates,and each replicate contained 4 mice.The experimental group(ZEA group)was administered ZEA by gavage at a dosage of 20 mg/kg body weight once daily for one week,and the control group(CON group)was given an equal volume of vector.Intestinal mucosa related indicators were measured after one week of treatment.In vitro,effects of ZEA on IPEC-J2 cells were investigated by RNA-seq and cell biology research methods.Results are as follows:(1)Short-term ZEA exposure damaged the integrity of jejunal intestinal villi in mice and altered the abundance of Lactobacillus_intestinalis in the jejunum.ZEA exposure upregulated the mRNA expression levels of mucosal Defb1,Reg3?,Reg3?,Muc1 and Muc2 in jejunum.Moreover,ZEA induced the secretion of sIgA in jejunal mucosa,it promoted the expression and secretion of IL-1? and TNF-? and inhibited the expression and secretion of IL-10 in jejunum.Short-term ZEA exposure caused the colonic lumen to enlarge and changed the abundance of Proteobacteria and Lactobacillus.ZEA exposure downregulated the mRNA expression levels of mucosal Muc1,Muc2 and Reg3? in the colon,while mRNA expression levels of mucosal Defb1,Reg3?,Reg3? were significantly upregulated.ZEA induced the secretion of sIgA in the colonic mucosa and inhibits the expression and secretion of IL-1? in the colon.The study shown that ZEA exposure caused mucosal damage and induced an inflammatory response in jejunum.In addition,ZEA exposure did not damage the colonic mucosa,but increased the abundance of Lactobacillus.We believe that microbial flora in different intestinal segments respond differently to exposure to exogenous toxins(ZEA)and Lactobacillus play a critical role in the intestinal mucosal barrier.However,the specific role of Lactobacillus in the defense against exogenous toxin ZEA remains to be explored.(2)20 ?M ZEA exposure decreased cell viability of IPEC-J2 and increased the lactate dehydrogenase(LDH).ZEA caused the cell cycle to arrest in the G2 phase,thereby inhibited cell proliferation and caused damage to IPEC-J2 cells.Based on RNA-seq,differentially expressed genes are involved in the cell cycle,P53 and TNF signaling pathway.And we selected 10 genes related to cell proliferation and inflammation for QPCR validation.These results indicated that ZEA inhibited cell proliferation and induced cell inflammation by affecting cell cycle,P53 signaling pathway and TNF signaling pathway.These results provided the theoretical foundation for the prevention and treatment of ZEA exposure.