EPA and DHA confer protection against deoxynivalenol-induced endoplasmic reticulum stress and iron imbalance in IPEC-1 cells

Abstract

This study assessed the molecular mechanism of eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA) protection against IPEC-1 cell damage induced by deoxynivalenol (DON). The cells were divided into six groups, including the CON group, the EPA group, the DHA group, the DON group, the EPA+DON group, and the DHA+DON group. RNA sequencing was used to investigate the potential mechanism, and qRT-PCR was employed to verify the expression of selected genes. Changes in ultrastructure were used to estimate pathological changes and endoplasmic reticulum (ER) injury in IPEC-1 cells. Transferrin receptor 1 (TFR1) was tested by ELISA. Fe2+ and malondialdehyde (MDA) contents were estimated by spectrophotometry, and reactive oxygen species (ROS) was assayed by fluorospectrophotometry. RNA sequencing analysis showed that EPA and DHA had a significant effect on the expression of genes involved in ER stress and iron balance during DON-induced cell injury. The results showed that DON increased ER damage, the content of MDA and ROS, the ratio of X-box binding protein 1s (XBP-1s)/X-box binding protein 1u (XBP-1u), the concentration of Fe2+, and the activity of TFR1. However, the results also showed that EPA and DHA decreased the ratio of XBP-1s/XBP-1u to relieve DON-induced ER damage of IPEC-1 cells. Moreover, EPA and DHA (especially DHA) reversed the factors related to iron balance. It can be concluded that EPA and DHA reversed IPEC-1 cell damage induced by DON. DHA has the potential to protect IPEC-1 cells from DON-induced iron imbalance by inhibiting ER stress.

Effects of DON on Mitochondrial Function, Endoplasmic Reticulum Stress, and Endoplasmic Reticulum Mitochondria Contact Sites in the Jejunum of Piglets

“…In recent years, studies aimed at investigating the regulatory mechanisms underlying the effects of DON on pigs have predominantly focused on specific single organelles such as mitochondria and ER. , This has led to a limited understanding of the comprehensive regulatory network in response to the toxic effects of DON in piglets. Actually, organelles can interact with each other through the physical contacts between them such as the ERMCSs between mitochondria and ER, which was first discovered by Vance and has recently garnered increasing attention in the field of life science. , However, up to now, there is currently a lack of available data on the roles of ERMCSs involved in the intestinal health of piglets, except for one that we published earlier .…”

“…14 Recently, it has been reported that ERS can be triggered by DON in intestinal porcine epithelial cell line 1 (IPEC-1). 7 However, little data have been reported about how ER was regulated in response to DON-induced intestinal injury in piglets.…”

“…As the primary target organ for DON attack, mitochondria or endoplasmic reticulum (ER) has been reported in previous studies that is used to target DON-induced intestinal injury in piglets. , To maintain normal intestinal barrier function and structural integrity, mitochondria is primarily responsible for generating a large amount of energy required by the intestine. , Under stress conditions, mitochondria not only plays the main role in providing intracellular ROS but also is a crucial attack target of it . The normal function of mitochondria such as mitochondrial membrane potential (MMP) is the foundation of energy metabolism in cells .…”

“…Under ERS, three unfolded protein pathways including PERK, IRE-1α, and ATF6 were triggered to restore the homeostasis of ER . Recently, it has been reported that ERS can be triggered by DON in intestinal porcine epithelial cell line 1 (IPEC-1) . However, little data have been reported about how ER was regulated in response to DON-induced intestinal injury in piglets.…”

Insights into the intestinal toxicity of foodborne mycotoxins through gut microbiota: A comprehensive review

“…However, when ER stress occurs, mRNA translation is disrupted, and protein misfolding increases, potentially leading to various intestinal diseases (Stengel et al., 2020). Several studies have demonstrated that DON induces ER stress in IPEC‐1 cells by upregulating the proportion of X‐Box Binding Protein 1s (XBP‐1s)/XBP‐1u, thereby exacerbating its cytotoxicity (Lin et al., 2022; Song et al., 2023). Similarly, FB 1 triggers ER stress and damages the intestinal epithelial barrier through CerS2 depletion in the IPEC‐J2 cell model (Li, Liu, et al., 2022).…”