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. 2024 Sep 11;25(18):9826.
doi: 10.3390/ijms25189826.

Itaconic Acid Alleviates Perfluorooctanoic Acid-Induced Oxidative Stress and Intestinal Damage by Regulating the Keap1/Nrf2/Ho-1 Pathway and Reshaping the Gut Microbiota

Lianchi Wu  1 , Zhaoying Hu  1 , Xinyu Luo  1 , Chaoyue Ge  1 , Yujie Lv  1 , Shenao Zhan  1 , Weichen Huang  1 , Xinyu Shen  1 , Dongyou Yu  1   2 , Bing Liu  1   2
Affiliations

Itaconic Acid Alleviates Perfluorooctanoic Acid-Induced Oxidative Stress and Intestinal Damage by Regulating the Keap1/Nrf2/Ho-1 Pathway and Reshaping the Gut Microbiota

Lianchi Wu et al. Int J Mol Sci. .

Abstract

Itaconic acid (IA) is recognized for its potential application in treating intestinal diseases owing to the anti-inflammatory and antioxidant properties. Perfluorooctanoic acid (PFOA) can accumulate in animals and result in oxidative and inflammatory damages to multi-tissue and organ, particularly in the intestinal tract. This study aimed to explore whether IA could mitigate intestinal damage induced by PFOA exposure in laying hens and elucidate its potential underlying mechanisms. The results showed that IA improved the antioxidant capacity of laying hens and alleviated the oxidative damage induced by PFOA, as evidenced by the elevated activities of T-SOD, GSH-Px, and CAT, and the decreased MDA content in both the jejunum and serum. Furthermore, IA improved the intestinal morphological and structural integrity, notably attenuating PFOA-induced villus shedding, length reduction, and microvillus thinning. IA also upregulated the mRNA expression of ZO-1, Occludin, Claudin-1, and Mucin-2 in the jejunum, thereby restoring intestinal barrier function. Compared with the PF group, IA supplementation downregulated the gene expression of Keap1 and upregulated the HO-1, NQO1, SOD1, and GPX1 expression in the jejunum. Meanwhile, the PF + IA group exhibited lower expressions of inflammation-related genes (NF-κB, IL-1β, IFN-γ, TNF-α, and IL-6) compared to the PF group. Moreover, IA reversed the PFOA-induced imbalance in gut microbiota by reducing the harmful bacteria such as Escherichia-Shigella, Clostridium innocuum, and Ruminococcus torques, while increasing the abundance of beneficial bacteria like Lactobacillus. Correlation analysis further revealed a significant association between gut microbes, inflammatory factors, and the Keap1/Nrf2/HO-1 pathway expression. In conclusion, dietary IA supplementation could alleviate the oxidative and inflammatory damage caused by PFOA exposure in the intestinal tract by reshaping the intestinal microbiota, modulating the Keap1/Nrf2/HO-1 pathway and reducing oxidative stress and inflammatory response, thereby promoting intestinal homeostasis.

Keywords: inflammation; itaconic acid; oxidative stress; perfluorooctanoic acid.

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Conflict of interest statement

The authors declare that there are no conflicts of interest.

Figures

Figure 1
Figure 1
The changes in the antioxidant capacity of serum and jejunum. (A) Serum antioxidant capacity; (B) Antioxidant capacity of the jejunum. Results are means ± SEM; n = 6; * p < 0.05, ** p < 0.01.
Figure 2
Figure 2
The changes in the morphology of the jejunum in laying hens. (A) Photograph of representative jejunum HE and PAS staining. Quantification of VH (B), CD (C), VCR (D), and counts of GC (E). GC, goblet cells; CD, crypt depth; VH, villus height; VCR, the ratio of VH to CD. The Yellow arrows indicate inflammatory cell infiltration. Results are means ± SEM; n = 6; * p < 0.05, ** p < 0.01.
Figure 3
Figure 3
The changes in intestinal barrier function of the jejunum. (A) TEM images of the jejunum. (B) Relative mRNA levels of tight junction proteins. (C) Serum indicators of intestinal permeability. Results are means ± SEM; n = 6; * p < 0.05, ** p < 0.01.
Figure 4
Figure 4
The changes in the expression of jejunal tight junction proteins. (A) Representative immunofluorescence photomicrographs for Occludin. (B) Fluorescence intensity analysis of Occludin. (C) Representative immunofluorescence photomicrographs for MUC-2. (D) Fluorescence intensity analysis of MUC-2. Results are means ± SEM; n = 6; * p < 0.05, ** p < 0.01.
Figure 5
Figure 5
The changes in the jejunal Keap1/Nrf2/HO-1 pathway. (A) Representative immunofluorescence photomicrographs for Nrf2. (B) Fluorescence intensity analysis of Nrf2. The expression of (C) Nrf2, (D) Keap1, (E) HO-1, (F) NQO1, (G) SOD1, and (H) GPX1 mRNA. Results are means ± SEM; n = 6; * p < 0.05, ** p < 0.01.
Figure 6
Figure 6
The changes in gene expression of jejunal inflammatory factors. The expression of (A) NF-κB, (B) IL-1β, (C) IFN-γ, (D) TNF-α, (E) IL-6, and (F) IL-8 mRNA. Results are means ± SEM; n = 6; * p < 0.05, ** p < 0.01.
Figure 7
Figure 7
The changes in the composition of the cecal microbiota. (A) Rarefaction curves. (B) OUT Venn. (C) α diversity indices. (D) microbial dysbiosis index. * p < 0.05, ** p < 0.01, *** p < 0.001.
Figure 8
Figure 8
The alterations in the composition of the cecal microbiota. (A) Comparison of β diversity indices. (A) Principal Component Analysis (PCA). (B) Principal co-ordinates analysis (PCoA). (C) Non-metric multidimensional scaling analysis (NMDS). (D) Microbiota composition at the phylum level. (E) Microbiota composition at the genus level.
Figure 9
Figure 9
The changes in the cecal microbiota composition. (A) The cladogram of LEfSe analysis. (B) The histogram of LEfSe analysis. (C) Differences in microbiota composition at phylum level. (D) Differences in microbiota composition at genus level. * p < 0.05, ** p < 0.01, *** p < 0.001.
Figure 10
Figure 10
Correlation analysis between gut microbiota and oxidative stress and inflammatory parameters. (A) At family level. (B) At genus level. * p < 0.05, ** p < 0.01, *** p < 0.001.
Figure 11
Figure 11
Schematic representation of potential mechanisms by itaconic acid alleviates intestinal damage and oxidative stress induced by PFOA.
See this image and copyright information in PMC

References

    1. Zhang J., Hu L., Xu H. Dietary Exposure to Per- and Polyfluoroalkyl Substances: Potential Health Impacts on Human Liver. Sci. Total Environ. 2024;907:167945. doi: 10.1016/j.scitotenv.2023.167945. - DOI - PubMed
    1. Zhou Y.-T., Li R., Li S.-H., Ma X., Liu L., Niu D., Duan X. Perfluorooctanoic Acid (PFOA) Exposure Affects Early Embryonic Development and Offspring Oocyte Quality via Inducing Mitochondrial Dysfunction. Environ. Int. 2022;167:107413. doi: 10.1016/j.envint.2022.107413. - DOI - PubMed
    1. Gazzotti T., Sirri F., Ghelli E., Zironi E., Zampiga M., Pagliuca G. Perfluoroalkyl Contaminants in Eggs from Backyard Chickens Reared in Italy. Food Chem. 2021;362:130178. doi: 10.1016/j.foodchem.2021.130178. - DOI - PubMed
    1. Roth K., Yang Z., Agarwal M., Liu W., Peng Z., Long Z., Birbeck J., Westrick J., Liu W., Petriello M.C. Exposure to a Mixture of Legacy, Alternative, and Replacement per- and Polyfluoroalkyl Substances (PFAS) Results in Sex-Dependent Modulation of Cholesterol Metabolism and Liver Injury. Environ. Int. 2021;157:106843. doi: 10.1016/j.envint.2021.106843. - DOI - PMC - PubMed
    1. Li P., Oyang X., Xie X., Li Z., Yang H., Xi J., Guo Y., Tian X., Liu B., Li J., et al. Phytotoxicity Induced by Perfluorooctanoic Acid and Perfluorooctane Sulfonate via Metabolomics. J. Hazard. Mater. 2020;389:121852. doi: 10.1016/j.jhazmat.2019.121852. - DOI - PubMed

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