Whole transcriptome-based ceRNA network analysis revealed ochratoxin A-induced compromised intestinal tight junction proteins through WNT/Ca2+ signaling pathway

Selenium deficiency modulates necroptosis-mediated intestinal inflammation in broiler through the lncRNAWSF27/miRNA1696/GPX3 axis

Deficiency of selenium (Se), an important trace element, causes diarrhea and even death in broilers, thereby affecting the economic development of poultry production. Adding Se is one way to relieve this situation; however, it has not fundamentally resolved intestinal inflammation. Therefore, we sought a new strategy to alleviate intestinal inflammation by studying the specific mechanisms of Se deficiency. By replicating the Se-deficient broiler model and establishing a chicken small intestinal epithelial cell (CSIEC) model, we determined that Se deficiency caused intestinal oxidative stress and necroptotic intestinal inflammation in broilers by decreasing glutathione peroxidase (GPX) 3 expression. Simultaneously, the expression of long non-coding RNA (lncRNA)WSF27 decreased and that of miR-1696 increased in Se-deficient intestines. Recently discovered competing endogenous RNAs (ceRNAs) form novel regulatory networks, which were found that selenoproteins are involved in ceRNA regulation. However, the mechanism of action of the non-coding RNA/GPX3 axis in Se-deficient broiler intestinal inflammation remains unclear. This study aimed to explore the mechanism through which Se deficiency regulates intestinal inflammation in broilers through the lncRNAWSF27/miR-1696/GPX3 axis. Our previous studies showed that lncRNAWSF27, miR-1696, and GPX3 have ceRNA-regulatory relationships. To further determine the role of the lncRNAWSF27/miR-1696/GPX3 axis in Se-deficient broiler intestinal inflammation, CSIEC models with GPX3 knockdown/overexpression, lncRNAWSF27 knockdown, or miR-1696 knockdown/overexpression were established to simulate intestinal injury. GPX3 knockdown, as well as lncRNAWSF27 and miR-1696 overexpression, aggravated cell damage. On the contrary, it can alleviate this situation. Our results reveal that the mechanism of lncRNAWSF27/miR-1696/GPX3 regulated Se-deficient broiler intestinal inflammation. This conclusion enriches our understanding of the mechanism of intestinal injury caused by Se deficiency and contributes to the diagnosis of Se-deficient intestinal inflammation and relevant drug development.

Whole transcriptome profiling reveals a lncMDP1 that regulates myogenesis by adsorbing miR-301a-5p targeting CHAC1

Myoblast proliferation and differentiation are essential for skeletal muscle development. In this study, we generated the expression profiles of mRNAs, long noncoding RNAs (lncRNAs), and microRNAs (miRNAs) in different developmental stages of chicken primary myoblasts (CPMs) using RNA sequencing (RNA-seq) technology. The dual luciferase reporter system was performed using chicken embryonic fibroblast cells (DF-1), and functional studies quantitative real-time polymerase chain reaction (qPCR), cell counting kit-8 (CCK-8), 5-Ethynyl-2'-deoxyuridine (EdU), flow cytometry cycle, RNA fluorescence in situ hybridization (RNA-FISH), immunofluorescence, and western blotting assay. Our research demonstrated that miR-301a-5p had a targeted binding ability to lncMDP1 and ChaC glutathione-specific gamma-glutamylcyclotransferase 1 (CHAC1). The results revealed that lncMDP1 regulated the proliferation and differentiation of myoblasts via regulating the miR-301a-5p/CHAC1 axis, and CHAC1 promotes muscle regeneration. This study fulfilled the molecular regulatory network of skeletal muscle development and providing an important theoretical reference for the future improvement of chicken meat performance and meat quality.

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

Mycotoxins, which are fungal metabolites, pose a significant global food safety concern by extensively contaminating food and feed, thereby seriously threatening public health and economic development. Many foodborne mycotoxins exhibit potent intestinal toxicity. However, the mechanisms underlying mycotoxin-induced intestinal toxicity are diverse and complex, and effective prevention or treatment methods for this condition have not yet been established in clinical and animal husbandry practices. In recent years, there has been increasing attention to the role of gut microbiota in the occurrence and development of intestinal diseases. Hence, this review aims to provide a comprehensive summary of the intestinal toxicity mechanisms of six common foodborne mycotoxins. It also explores novel toxicity mechanisms through the "key gut microbiota-key metabolites-key targets" axis, utilizing multiomics and precision toxicology studies with a specific focus on gut microbiota. Additionally, we examine the potential beneficial effects of probiotic supplementation on mycotoxin-induced toxicity based on initial gut microbiota-mediated mycotoxicity. This review offers a systematic description of how mycotoxins impact gut microbiota, metabolites, and genes or proteins, providing valuable insights for subsequent toxicity studies of mycotoxins. Furthermore, it lays a theoretical foundation for preventing and treating intestinal toxicity caused by mycotoxins and advancing food safety practices.

The coexistence of aflatoxin M1 and ochratoxin A induced intestinal barrier disruption via the regulation of key differentially expressed microRNAs and long non-coding RNAs in BALB/c mice

Food safety can be seriously threatened by the existence of both aflatoxin M1 (AFM1) and ochratoxin A (OTA) in milk and corresponding products. The importance of intestine integrity in preserving human health is widely understood in vitro, but the fundamental processes by which AFM1 and OTA cause disruption of the intestinal barrier are as yet unknown, especially in vivo. Based on the analysis of the whole transcriptome of BALB/c mice, the competing endogenous RNA (ceRNA) regulation network was obtained in the current study. Each of 12 mice were separated into five treatments: saline solution treatment, 1.0% DMSO vehicle control treatment, 3.0 mg/kg b.w. individual AFM1 treatment (AFM1), 3.0 mg/kg b.w. individual OTA treatment (OTA), and combined mycotoxins treatment (AFM1 +OTA). The study period lasted 28 days. The jejunum tissue was collected for the histological assessment and whole transcriptome analysis, and the whole blood was collected, and determination of serum biochemical indicators. The phenotypic results demonstrated that AFM1 and OTA caused intestinal barrier disruption via an increased apoptosis level and decreased expression of tight junction (TJ) proteins. The ceRNA network demonstrated that AFM1 and OTA induced cell apoptosis through activating the expression of DUSP9 and suppressing the expression of PLA2G2D, which were regulated by differentially expressed microRNAs (DEmiRNAs) (miR-124-y, miR-194-z, miR-224-x, and miR-452-x) and differentially expressed long non-coding RNAs (DElncRNAs) (FUT8 and GPR31C). And AFM1 and OTA decreased TJ proteins via inhibiting the expression of PAK6, which was regulated by several important DEmiRNAs and DElncRNAs. These DE RNAs in intestinal integrity were involved in MAPK and Ras signaling pathway. Overall, our findings expand the current knowledge regarding the potential mechanisms of intestinal integrity disruption brought on by AFM1 and OTA in vivo.

Integrated Metabolomics and Lipidomics Analysis Reveals Lipid Metabolic Disorder in NCM460 Cells Caused by Aflatoxin B1 and Aflatoxin M1 Alone and in Combination

Aflatoxin B1 (AFB1) and aflatoxin M1 (AFM1) are universally found as environmental pollutants. AFB1 and AFM1 are group 1 human carcinogens. Previous sufficient toxicological data show that they pose a health risk. The intestine is vital for resistance to foreign pollutants. The enterotoxic mechanisms of AFB1 and AFM1 have not been clarified at the metabolism levels. In the present study, cytotoxicity evaluations of AFB1 and AFM1 were conducted in NCM 460 cells by obtaining their half-maximal inhibitory concentration (IC50). The toxic effects of 2.5 μM AFB1 and AFM1 were determined by comprehensive metabolomics and lipidomics analyses on NCM460 cells. A combination of AFB1 and AFM1 induced more extensive metabolic disturbances in NCM460 cells than either aflatoxin alone. AFB1 exerted a greater effect in the combination group. Metabolomics pathway analysis showed that glycerophospholipid metabolism, fatty acid degradation, and propanoate metabolism were dominant pathways that were interfered with by AFB1, AFM1, and AFB1+AFM1. Those results suggest that attention should be paid to lipid metabolism after AFB1 and AFM1 exposure. Further, lipidomics was used to explore the fluctuation of AFB1 and AFM1 in lipid metabolism. The 34 specific lipids that were differentially induced by AFB1 were mainly attributed to 14 species, of which cardiolipin (CL) and triacylglycerol (TAG) accounted for 41%. AFM1 mainly affected CL and phosphatidylglycerol, approximately 70% based on 11 specific lipids, while 30 specific lipids were found in AFB1+AFM1, mainly reflected in TAG up to 77%. This research found for the first time that the lipid metabolism disorder caused by AFB1 and AFM1 was one of the main causes contributing to enterotoxicity, which could provide new insights into the toxic mechanisms of AFB1 and AFM1 in animals and humans.

Effects of Houpo Mahuang Decoction on serum metabolism and TRPV1/Ca2+/TJs in asthma

ETHNOPHARMACOLOGICAL RELEVANCE

Houpo Mahuang Decoction (HPMHD is one of the classic traditional Chinese prescriptions that has been used in the treatment of asthma. The therapeutic effects and mechanism of HPMHD in aggravated asthma remain to be explored, especially from the perspective of metabolomics and Transient Receptor Potential Vanilloid-1 (TRPV1)/Ca²⁺/Tight junction (TJ) regulation.

AIM OF THE STUDY

To investigate the therapeutic and metabolic regulatory effects and the underlying mechanism of HPMHD in asthmatic rats.

MATERIALS AND METHODS

The asthmatic rats were administered with the corresponding HPMHD (at dosages of 5.54, 11.07, 22.14 mg/kg). Then inflammatory cells in peripheral blood and bronchoalveolar lavage fluid (BALF) were counted, the levels of interleukin (IL)-4 and IL-13 in BALF were measured, and the changes in enhanced pause (Penh) and pathological damage of lung tissues were also detected to evaluate the protective effects of HPMHD. The serum metabolic profile of HPMHD in asthmatic rats was explored using Ultra-High-Performance Liquid Chromatography-mass spectrometer (UHPLC-MS), and the regulatory effects on TRPV1 and TJs of HPMHD in asthmatic rats were detected by Western blotting analysis. In vitro, 16HBE cells were stimulated with IL-4 plus SO₂ derivatives and then administered HPMHD. The intracellular Ca²⁺ regulated by TRPV1, and the expression levels of TRPV1 and TJ proteins (TJs) were then detected by calcium imaging and Western blotting. The effects were verified by inhibition of TRPV1 and in short hairpin RNA (shRNA)-mediated TRPV1 silencing cells.

RESULTS

HPMHD significantly attenuated the airway inflammation of asthmatic rats, and reduced the levels of inflammatory cells in peripheral blood and BALF as well as the levels of IL-4 plus IL-13 in BALF. In addition, the airway hyperresponsiveness and lung pathological damage were alleviated. Serum metabolomic analysis showed that 31 metabolites were differentially expressed among the normal saline-, model-, and HPMHD-treated rats. Pathway enrichment analysis showed that the metabolites were involved in 45 pathways, among which, TJs regulation-relevant pathway was associated with the Ca²⁺ concentration change mediated by the TRP Vanilloid channel. In vivo and in vitro experiments indicated that HPMHD reduced the concentration of intracellular Ca²⁺ via suppressing the expression and activation of TRPV1, increased the expression of ZO-1, Occludin, and Claudin-3, and protected the integrity of TJs.

CONCLUSION

The current study indicates that HPMHD alleviates rat asthma and participates in the regulation of serum metabolism. The anti-asthma effects of HPMHD might be related to the protection of TJs by inhibiting the intracellular Ca²⁺ concentration via TRPV1.

Aflatoxin M1 and ochratoxin A induce a competitive endogenous RNA regulatory network of intestinal immunosuppression by whole-transcriptome analysis

Aflatoxin M1 (AFM1) and ochratoxin A (OTA) are common mycotoxins in cereal foods and milk products, and may cause serious negative impacts on human health. The intestine is crucial for immune regulation as it protects host homeostatic health from external contaminants; however, the underlying mechanisms of AFM1 and OTA mediated intestinal immunotoxicity remain unclear. In this study, whole transcriptome analysis was used to characterize BALB/c mouse intestines exposed to individual and combined AFM1 and OTA [3.0 mg/kg body weight (BW)] for 28 days to screen for key intestinal immunotoxicity-related differentially expressed mRNAs (DEmRNAs), differentially expressed microRNAs (DEmiRNAs), differentially expressed long non-coding RNAs (DElncRNAs), and associated enriched signaling pathways. Functional validation was then conducted in intestinal differentiated Caco-2 cells using different inhibitor assays to verify the accuracy of transcriptome and the importance of the key screened regulatory factors. In vivo data revealed that AFM1 and OTA exposure disrupted the intestines and exerted intestinal immunosuppression effects. When compared with AFM1, OTA had stronger intestinal toxicity in combined treatments. Further analyses of competitive endogenous RNA (ceRNA) regulatory networks in mice showed that AFM1 and OTA mediated-intestinal immunosuppression was putatively explained as follows: (i) toxins affected DEmRNAs regarding transfer and transduction mechanisms between cells (Csf1, Csf1r, Cxcl10, Cx3cr1, and Irf1), which were regulated by key DEmiRNAs (miR-106-x, miR-107-y, and miR-124-y) and the DElncRNA Rian, and (ii) toxins inhibited transforming growth factor-β-activated kinase 1 (TAK1)/I-kappaB kinase (IKK)/inhibitor of kappa Bα (IκBα)/p65 nuclear factor-κB (NF-κB) signaling phosphorylation levels, which was validated in differentiated Caco-2 cells using the TAK1 inhibitor (5Z-7-oxozeaenol). In conclusion, we evaluated the risk of co-exposure to AFM1 and OTA and associated health hazards from a whole transcriptome perspective.

Multi-Omics Reveal Additive Cytotoxicity Effects of Aflatoxin B1 and Aflatoxin M1 toward Intestinal NCM460 Cells

Aflatoxin B1 (AFB1) is a common crop contaminant, while aflatoxin M1 (AFM1) is implicated in milk safety. Humans are likely to be simultaneously exposed to AFB1 and AFM1; however, studies on the combined interactive effects of AFB1 and AFM1 are lacking. To fill this knowledge gap, transcriptomic, proteomic, and microRNA (miRNA)-sequencing approaches were used to investigate the toxic mechanisms underpinning combined AFB1 and AFM1 actions in vitro. Exposure to AFB1 (1.25–20 μM) and AFM1 (5–20 μM) for 48 h significantly decreased cell viability in the intestinal cell line, NCM460. Multi-omics analyses demonstrated that additive toxic effects were induced by combined AFB1 (2.5 μM) and AFM1 (2.5 μM) in NCM460 cells and were associated with p53 signaling pathway, a common pathway enriched by differentially expressed mRNAs/proteins/miRNAs. Specifically, based on p53 signaling, cross-omics showed that AFB1 and AFM1 reduced NCM460 cell viability via the hsa-miR-628-3p- and hsa-miR-217-5p-mediated regulation of cell surface death receptor (FAS), and also the hsa-miR-11-y-mediated regulation of cyclin dependent kinase 2 (CDK2). We provide new insights on biomarkers which reflect the cytotoxic effects of combined AFB1 and AFM1 toxicity.