Transcriptome Analysis of Ochratoxin A-Induced Apoptosis in Differentiated Caco-2 Cells

Abstract

Ochratoxin A (OTA), an important mycotoxin that occurs in food and animal feed, has aroused widespread concern in recent years. Previous studies have indicated that OTA causes nephrotoxicity, hepatotoxicity, genotoxicity, immunotoxicity, cytotoxicity, and neurotoxicity. The intestinal toxicity of OTA has gradually become a focus of research, but the mechanisms underlying this toxicity have not been described. Here, differentiated Caco-2 cells were incubated for 48 h with different concentrations of OTA and transcriptome analysis was used to estimate damage to the intestinal barrier. Gene expression profiling was used to compare the characteristics of differentially expressed genes (DEGs). There were altogether 10,090 DEGs, mainly clustered into two downregulation patterns. The Search Tool for Retrieval of Interacting Genes (STRING), which was used to analyze the protein–protein interaction network, indicated that 24 key enzymes were mostly responsible for regulating cell apoptosis. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) analysis was used to validate eight genes, three of which were key genes (CASP3, CDC25B, and EGR1). The results indicated that OTA dose-dependently induces apoptosis in differentiated Caco-2 cells. Transcriptome analysis showed that the impairment of intestinal function caused by OTA might be partly attributed to apoptosis, which is probably associated with downregulation of murine double minute 2 (MDM2) expression and upregulation of Noxa and caspase 3 (CASP3) expression. This study has highlighted the intestinal toxicity of OTA and provided a genome-wide view of biological responses, which provides a theoretical basis for enterotoxicity and should be useful in establishing a maximum residue limit for OTA.

Nutritional impact of mycotoxins in food animal production and strategies for mitigation

“…The intestinal epithelium is the first site of exposure following mycotoxin ingestion and may be exposed to higher concentrations than other tissues [ 17 ]. Changes in villus height reflect the balance between intestinal epithelial cells (IEC) proliferation and apoptosis [ 89 , 107 ], which is in line with findings that several mycotoxins can cause oxidative stress induced IEC apoptosis and cell cycle arrest both in vivo and in vitro [ 108 – 110 ]. Previous studies suggested effects of mycotoxins on the intestinal morphology may appear to be section-specific, with effects on duodenum and jejunum being more pronounced than ileum [ 49 , 57 , 89 , 111 ].…”

Anti‐inflammatory actions of acetate, propionate, and butyrate in fetal mouse jejunum cultures ex vivo and immature small intestinal cells in vitro

“…Differentially expressed pathways were verified by Western blot. Protein extraction and Western blot were performed as previously mentioned (Yang et al., 2019). Antibodies were used according to the manufacturer's instruction: NF‐κB p65, pNF‐κB p65, ERK, pERK1/2, JNK (Cell Signaling Technology), pJNK1/2 (Invitrogen), and goat anti‐rabbit IgG/HRP (Bioss).…”

The Compromised Intestinal Barrier Induced by Mycotoxins

“…In addition, AFM1 and OTA inhibited the cell viability of the co-culture of Caco-2/HT29-MTX [ 43 ]. Equally, OTA promoted apoptosis in IPEC-J2 and Caco-2 cells by inducing mitochondrial reactive oxygen species (ROS) and arresting the cell cycle [ 81 , 82 , 83 ]. Apart from mycotoxin effects in human intestinal cells, DON inhibited intestinal epithelial cell viability and induced apoptosis in rat and pig cell models [ 84 , 85 , 86 , 87 , 88 ].…”