Zearalenone regulates key factors of the Kelch-like erythroid cell-derived protein with CNC homology-associated protein 1–nuclear factor erythroid 2-related factor 2 signaling pathway in duodenum of post-weaning gilts

Abstract

Objective: This study explored the mechanism of the Kelch-like erythroid cell-derived protein with CNC homology-associated protein 1 (Keap1)-nuclear factor erythroid 2-related factor (Nrf2) signaling pathway under conditions of ZEA-induced oxidative stress in the duodenum of post-weaning gilts. Methods: Forty post-weaning gilts were randomly allocated to four groups and fed diets supplemented with 0, 0.5, 1.0, or 1.5 mg/kg ZEA. Results: The results showed significant reductions in the activity of the antioxidant enzymes total superoxide dismutase (T-SOD) and glutathione peroxidase (GSH-Px), and increases the malondialdehyde (MDA) content with increasing concentrations of dietary ZEA. Immunohistochemical analysis supported these findings by showing a significantly increased expression of Nrf2 and glutathione peroxidase 1 (GPX1) with increasing concentrations of ZEA. The relative mRNA and protein expression of Nrf2, GPX1 increased linearly (p<0.05) and quadratically (p<0.05), which was consistent with the immunohistochemical results. The relative mRNA expression of Keap1 decreased linearly (p<0.05) and quadratically (p<0.05) in the duodenum as the ZEA concentration increased in the diet. The relative mRNA expression of modifier subunit of glutamate-cysteine ligase (GCLM) increased quadratically (p<0.05) in all ZEA treatment groups and the relative mRNA expression of quinone oxidoreductase 1 (NQO1) catalytic subunit of glutamate-cysteine ligase (GCLC) decreased linearly (p<0.05) and quadratically (p<0.05) in the ZEA1.0 group and ZEA1.5 group. The relative protein expression of Keap1 and GCLM decreased quadratically (p<0.05) in the duodenum as the ZEA concentration increased in the diet, respectively. The relative protein expression of NQO1 increased linearly (p<0.05) and quadratically (p<0.05) in all ZEA treatment groups in the duodenum. Conclusion: These findings suggest that ZEA regulates the expression of key factors of the Keap1-Nrf2 signaling pathway in the duodenum, which enables resistance to ZEA-induced oxidative stress. Further studies are needed to examine the effects of ZEA-induced oxidative stress on other tissues and organs in post-weaning gilts.

Zearalenone Exposure Affects the Keap1–Nrf2 Signaling Pathway and Glucose Nutrient Absorption Related Genes of Porcine Jejunal Epithelial Cells

“…Meanwhile, Nrf2 immunofluorescence showed that ZEA significantly induced the increase of Nrf2 gene expression in the cells, and Nrf2 transferred from the cytoplasm to the nucleus. Nrf2 expression reached its maximum level in the ZEA40 treatment group, which was consistent with our previous results in the pig intestine [11][12][13]. As a result, we think that ZEA can activate the Keap1-Nrf2 signaling pathway of IPEC-J2 cells, and the activation of this pathway increases the ability of IPEC-J2 cells to resist ZEA toxicity.…”

“…The relative expression of ROS mRNA and protein as well as the MDA content in the cells were dramatically raised following ZEA treatment of IPEC-J2 cells for 24 h and 36 h in this investigation, whereas the activities of the antioxidant enzymes T-SOD and GSH-PX were significantly decreased. ZEA promotes a large number of cells in a state of oxidative stress, which is consistent with our previous research results in the pig intestine [11][12][13]. Some studies also found that the level of ROS in human embryonic kidney cells exposed to ZEA for 1 h did not change significantly, but it increased significantly after 2 h [50].…”

“…ZEA can alter intestinal villi structure [7,8], affect the integrity of porcine intestinal epithelial cells [9], and guide significant changes in gene expression levels of porcine intestinal cells [10]. We have found, in vivo, that ZEA can induce intestinal tissue damage, cause intestinal oxidative stress, and activate the Kelch-like erythroid cell-derived protein with CNC homology-associated protein 1 (Keap1)-nuclear factor erythroid 2-related factor 2 (Nrf2) signal pathway in post-weaning piglets [11][12][13]. Combining in vitro research is required to further demonstrate the potential contribution of the Keap1-Nrf2 signaling pathway to ZEA-induced intestinal oxidative stress since the internal environment governs the interaction and influence between various tissues and organs.…”

Quercetin Attenuates the Combined Effects of Zearalenone and Lipopolysaccharide on IPEC-J2 Cell Injury through Activating the Nrf2 Signaling Pathway

“…In Caco-2 cells, it was found that 100 μM QUE could protect the cell barrier function by inhibiting CHOP gene expression and suppressing the Bax/Bcl2 ratio, thereby inhibiting indomethacin- and diclofenac-induced apoptosis [ 39 ]. Different reports have also been published regarding in vivo studies in gilts, showing that ZEA alters the expression of key genes and proteins in the Nrf2 signaling pathway of duodenum and can resist ZEA-induced intestinal oxidative stress [ 40 ]. In contrast to the present study in an in vitro model, the combined effects of LPS and ZEA, which did not resist oxidative stress, may be simultaneous.…”

Quantitative Proteomic Analysis of Zearalenone-Induced Intestinal Damage in Weaned Piglets

“…Zearalenone and its metabolites are classified as xenoestrogens due to their structural similarity to endogenous estrogens [ 2 , 3 ]. Previous studies have shown that ZEN exposure can induce an immune response, oxidative damage, and other pathological changes in different tissues of the body, causing organ damage, decreased productive and reproductive performance, and even acute animal death in severe cases [ 4 , 5 , 6 ].…”