Search Results (225)

Mycotoxins represent a group of highly toxic secondary metabolites produced by diverse fungal pathogens. Mycotoxin contaminations frequently occur in foods and feed and pose significant risks to human and animal health due to their carcinogenic, mutagenic, and immunosuppressive properties. Notably, deoxynivalenol, zearalenone, fumonisins (mainly including fumonisins B1, B2, and FB3), aflatoxin B1 (AFB1), and T-2/HT-2 toxins are the major mycotoxin contaminants in foods and feed. Undoubtedly, exposure to these mycotoxins can disrupt gut health, particularly damaging the intestinal epithelium in humans and animals. In this review, we summarized the detrimental effects caused by these mycotoxins on the intestinal health of humans and animals. The fundamental molecular mechanisms, which cover the induction of inflammatory reaction and immune dysfunction, the breakdown of the intestinal barrier, the triggering of oxidative stress, and the intestinal microbiota imbalance, were explored. These signaling pathways, such as MAPK, Akt/mTOR, TNF, TGF-β, Wnt/β-catenin, PKA, NF-kB, NLRP3, AHR, TLR2, TLR4, IRE1/XBP1, Nrf2, and MLCK pathways, are implicated. The abnormal expression of micro-RNA also plays a critical role. Finally, we anticipate that this review can offer new perspectives and theoretical foundations for controlling intestinal health issues caused by mycotoxin contamination and promote the development of prevention and control products. Full article

The intestinal barrier governs organismal health through nutrient absorption, microbial homeostasis, and immune surveillance. While calorie restriction (CR) enhances metabolic health, the molecular mechanisms underlying its beneficial effects on gut integrity remain unclear. Here, we demonstrate that the aryl hydrocarbon receptor (AHR), a conserved xenobiotic sensor and metabolic regulator, is essential for CR-mediated improvements in intestinal function. Using Caenorhabditis elegans (C. elegans), we subjected wild-type (N2) and AHR-deficient strains (CZ2485 and ZG24) to ad libitum feeding (AL), intermittent fasting (IF), or complete food deprivation (FD). In wild-type animals, intermittent fasting markedly reduced intestinal permeability and bacterial burden while enhancing mitochondrial function and reducing reactive oxygen species. Complete food deprivation conferred modest benefits. Remarkably, these protective effects were severely compromised in AHR mutants, which exhibited increased gut leakage, bacterial colonization, and mitochondrial oxidative stress under fasting conditions. These findings establish AHR as a critical mediator of fasting-induced intestinal resilience, revealing a previously unrecognized regulatory axis linking metabolic sensing to gut barrier homeostasis. Our work illuminates fundamental mechanisms through which calorie restriction promotes gastrointestinal health and identifies AHR-dependent pathways as promising therapeutic targets for metabolic and inflammatory distress affecting the gut–systemic interface. Full article

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) exposure has long been associated with reproductive dysfunction in males and females even at miniscule levels, which can persist across generations. Given the continued industrial use and detection of other aryl hydrocarbon receptor (AhR) agonists in the general population and the demonstrated heritable phenotypes of TCDD exposure, further work is justified to elucidate reproductive pathologies and minimize exposure risk. In females, multi- and transgenerational subfertility has been demonstrated in a zebrafish (Danio rerio) model exposed to 50 pg/mL TCDD once at 3 and 7 weeks post fertilization (wpf). We further characterize the histopathologic, hormonal and transcriptomic outcomes of the mature female zebrafish ovary following early-life TCDD exposure. Exposure was associated with significantly increased ovarian atresia in the F0 and F1, but not F2 generation. Other oocyte staging and vitellogenesis were unaffected in all generations. Exposed F0 females showed increased levels of whole-body triiodothyronine (T3) and 17β-estradiol (E2) levels, but not vitellogenin (Vtg), 11-ketotestosterone (11-KT), cortisol, thyroxine (T4), or testosterone (T). Ovarian transcriptomics were most dysregulated in the F2. Both F0 and F2, but not F1, showed changes in epigenetic-related gene expression. Rho signaling was the top pathway for both F0 and F2. Full article

Industrial development has increased environmental dioxin concentrations, sparking concern about human health impacts. Examining dioxin neurotoxicity has highlighted associations with cognitive impairment and behavioral abnormality. Dioxins are ligands of the aryl hydrocarbon receptor (AHR), a ligand-activated transcription factor; it is speculated that dioxin-induced AHR activation is pivotal for toxic effects. Accurate AHR-expressing cell identification is therefore indispensable for understanding the molecular and cellular mechanisms of dioxin toxicity. Herein, current knowledge regarding AHR expression in the mammalian brain is summarized, and dioxin neurotoxicity mechanisms are discussed. Histological studies show AHR-expressing neurons in multiple brain regions, including the hippocampus and cerebral cortex. Dopaminergic and noradrenergic neurons exhibit AHR expression, suggesting possible roles in the monoaminergic system. AHR overactivation evokes dendritic arborization atrophy, whereas its deficiency increases complexity, implying that AHR-mediated signaling is crucial for neuronal growth and maturation. AHR is also involved in neurogenesis and neuronal precursor migration. Collectively, these findings support the notion that dioxin-induced AHR overactivation in individual neurons disrupts neural circuit structure, ultimately leading to impaired brain function. However, as AHR downstream signaling is intertwined with various molecules and pathways, the precise mechanisms remain unclear. Further studies on the expression, signaling, and roles of AHR are needed to clarify dioxin neurotoxicity. Full article

Aberrant DNA methylation is a hallmark of colorectal cancer (CRC), contributing to tumor progression through the silencing of tumor suppressor genes and activation of oncogenes. Indicaxanthin (IND), a dietary betalain pigment from Opuntia ficus indica, has shown antiproliferative effects in CRC models, yet its epigenetic impact remains unexplored. In this study, we investigated the effects of IND on the methylome of Caco-2 cells using Reduced Representation Bisulfite Sequencing (RRBS). IND induced a global hypermethylation profile, particularly at gene promoters and CpG islands. Among the differentially methylated genes, 60% were protein-coding, and 10% encoded transcription factors, including PAX5 and TFAP4, both hypermethylated at active enhancers. Functional enrichment analysis revealed pathways beyond canonical intestinal functions, suggesting altered cell identity and plasticity. Transcription factor targets (SOX10, NFKB1, AHR, ARNT) were significantly enriched among the affected genes, several of which are involved in transdifferentiation processes. Methylation changes also indicated potential reprogramming toward epithelial cell types from pulmonary or neuroectodermal origin. Moreover, IND induced selective hypomethylation of Alu elements on chromosome 21 and hypermethylation of rDNA loci, hinting at suppressed ribosomal biogenesis. Overall, these findings highlight the epigenetic remodeling potential of IND and its possible role in modulating cell fate and metabolism in CRC cells. Full article

Environmental pollutants like PM2.5 contribute to chronic rhinosinusitis (CRS). The aryl hydrocarbon receptor (AhR), a contaminant sensor linked to tryptophan metabolites, is regulated by IL4I. However, how PM2.5 stimulation via IL4I1 influences AhR activation and CRS pathogenesis remains unclear. This study explored the IL4I1-AhR pathway in CRS using patient tissues, HNEpCs, and murine models. Methods included IHC, qRT-PCR, and WB under PM2.5 exposure, with further investigation into downstream effects on CYP1B1 and epithelial–mesenchymal transition (EMT). Significant upregulation of IL4I1, AhR, and CYP1B1 was observed in CRS tissues, with higher expression levels in CRS patients. Exposure to PM2.5 activated the IL4I1-AhR pathway, leading to decreased E-cadherin, increased N-cadherin and vimentin, and impaired nasal mucosal barrier function. In vitro experiments demonstrated that PM2.5-induced EMT in HNEpCs was mediated by IL4I1-dependent AhR activation. CH223191 reduced cell migration and EMT, while IL4I1 knockdown attenuated AhR activation and EMT marker expression. Murine models further confirmed that PM2.5 exacerbated nasal polyp formation and tissue remodeling via the IL4I1-AhR pathway. This study underscores the critical role of the IL4I1-AhR signaling pathway in PM2.5-induced nasal mucosal barrier dysfunction and EMT in CRS. IL4I1, as an upstream regulator of AhR, promotes EMT and nasal mucosal barrier disruption. Full article

Background: Microvascular complications in type 2 diabetes (T2D) and cancer share biological pathways, including chronic inflammation, dysregulated angiogenesis, and endothelial dysfunction, yet their impact on cancer risk and mortality remains unclear. This study evaluated whether T2D patients with microvascular complications face increased cancer incidence or cancer-related mortality. Methods: Using the Taiwan National Health Insurance Research Database, we identified individuals newly diagnosed with T2D (2008–2021) and assessed the outcomes with multivariable Cox proportional hazards models. Results: Our findings indicate that T2D patients with diabetic neuropathy, retinopathy, or chronic kidney disease do not have a significantly increased risk of major cancers, including those of the oral cavity, thyroid, breast, respiratory tract, digestive system, or lymphoid tissues. Similarly, microvascular complications were not associated with higher cancer-related mortality. However, microvascular complications significantly increased all-cause mortality in a dose-dependent manner: adjusted hazard ratio (aHR) 1.16 [95% CI: 1.15–1.17] for one complication, aHR 1.42 [1.38–1.45] for two, and aHR 1.71 [1.60–1.83] for three. Conclusions: In this nationwide cohort study, we demonstrate that while microvascular complications are associated with increased all-cause mortality in T2D, they do not appear to elevate cancer risk or cancer-specific mortality. These findings provide crucial epidemiological insights into the relationship between diabetes complications and cancer. Full article

Background/Objectives: Metabolic dysfunction-associated fatty liver disease (MAFLD) is a chronic hepatic condition marked by lipid buildup, lipotoxicity, and inflammation. Prior research indicates that 3,3′-Diindolemethane (DIM), a natural indole-type phytochemical that is abundant in brassicaceae vegetables, has been reported to reduce body weight and improve lipid metabolism in mice subjected to a high-fat diet (HFD). The aryl hydrocarbon receptor (AhR), a nuclear receptor implicated in lipid metabolism and immune regulation, serves as a functional receptor for DIM. However, the underlying signaling pathways that regulate MAFLD remain elusive. Our objective is to ascertain the beneficial impact of DIM on MAFLD and the associated mechanisms. Methods: Hematoxylin and eosin staining, together with Oil Red O staining, were utilized to assess the pathological changes and lipid deposition in the liver. Biochemical analysis was employed to measure levels of triglyceride (TG), total cholesterol (TC), free fatty acid (FFA), aspartate transaminase (AST), alanine transaminase (ALT), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C). The cell survival rate of HepG2 cells treated with palmitic acid (PA) and DIM was assessed using the CCK-8 assay. Flow cytometry was employed to measure the fluorescence intensity emitted by lipid droplets within cells. Western blotting analysis was performed to assess AhR pathway and fatty acid transporter expression levels in hepatic tissue. Results: Our results showed that DIM significantly attenuated body weight gain and hepatic injury brought on by HFD, decreased lipid droplet accumulation in HepG2 cells, and effectively suppressed the phosphorylation of p38 MAPK and the protein expression levels of fatty acid transporters CD36 and FATP4. Conclusions: DIM reduced lipid accumulation by activating AhR and suppressing p38 MAPK phosphorylation, thereby inhibiting fatty acid transport and inflammatory responses. These findings suggest that DIM may represent a promising therapeutic candidate for MAFLD, warranting further exploration for clinical applications. Full article

Disruption in macrophage polarization is linked to inflammatory diseases and metabolic disorders. Our study aimed to investigate how AHR activation by I3C and TCDD could impact glucose transporters and macrophage phenotypes and functions in human macrophages. Human monocyte-derived macrophages (hMDMs) and THP-1 cell-derived macrophage-like cells were treated for 24 h with 100 ng/mL LPS, 100 nM TCDD, and 10 ng/µL I3C. CYP1A1 and CYP1B1 expression was significantly increased in the I3C and TCDD treatments, with CYP1B1 showing a higher fold change in I3C compared to TCDD. The AHRR expression was the highest in the TCDD group. For macrophage polarization, I3C significantly elevated CD163 expression while reducing CD16 and CD86, indicative of M2-like polarization. Additionally, I3C promoted ARG1 expression and reduced NOS2 levels, while TCDD increased NOS2. A cytokine analysis revealed I3C-induced upregulation of IL-10 and TGF-β, while TCDD significantly elevated TNF-α and IL-12. I3C upregulated glucose transporter genes (GLUT1, GLUT3, GLUT6), in contrast to the downregulation observed in TCDD-treated cells. Our findings demonstrated that I3C distinctly modulates AHR activation genes, macrophage polarization, cytokine expression, and glucose transporter levels in THP-1 cells compared to the TCDD and LPS treatments. Our findings suggest that I3C favors an anti-inflammatory M2-like macrophage polarization coupled with enhanced metabolic activity. Full article

Background: Glioblastoma is “cold”. Consequently, immune checkpoint blockade therapy has failed to improve patients‘ survival, which is negatively correlated with patients’ peripheral MDSC counts. AHR is known to mediate immune-suppressive functions of certain tryptophan metabolites such as kynurenine; yet, there lack of reports on how AHR agonists affect glioma immunity. Methods/Objectives: We hypothesized that ITE could synergize with PD1 antibody as AHR is one major node of immune-suppressive pathways, and tested it using an immune-competent mouse glioma model. Results: The combination of ITE+PD1 antibody glioma MDSC was significantly reduced, along with increased infiltration of the CD4−CD8+ and CD4+CD8+ T cells, leading to extended mouse survival. ITE treatment alone significantly reduces the infiltration of CD11b+Ly6G+Ly6Clo cells, namely PMN-MDSCs, and neutrophils, while the combination with PD1 antibody significantly reduces all MDSCs plus neutrophils. The presence of ITE inhibits the expression of IL11 and the in vitro induction of MDSCs from mouse PBMCs by IL11. The identification of the ITE-AHR-IL11-MDSC pathway provides more mechanistic insights into AHR’s effects. The fact that ITE, which is otherwise immune-suppressive, can activate immunity in glioma indicates that searching for drugs targeting AHR should go beyond antagonists. Full article

Background: Gleason score (GS) 10 prostate cancer (PC) is a highly aggressive localized disease. Despite advances in treating high-risk PC, the clinical outcomes and molecular underpinnings of GS 10 remain unclear. This study aimed to determine whether GS 10 PC has distinct clinical outcomes from other “high-risk” cancers (i.e., Gleason 8–9) and identify genomic alterations driving its aggressive phenotype. Methods: A retrospective review of The Cancer Genome Atlas database identified patients with GS 8–10 PC who underwent radical prostatectomy. Clinical factors were compared between GS 10 and GS 8–9 cohorts. Time to biochemical recurrence (BCR) was analyzed using Kaplan–Meier and Cox regression. RNA sequencing identified differentially expressed genes, and protein–protein interaction networks identified hub genes. Results: Of 192 patients, 13 (6.8%) had GS 10 PC. After median follow-up of 37.87 months, GS 10 status was associated with significantly lower time to BCR (AHR, 2.67; 95% CI, 1.18–6.02; p = 0.018) compared to GS 8–9. Multiple genes (e.g., RAD54L, FAAH, AATK, MAST2) showed higher alteration frequencies, and high expression of RAD54L, MAST2, and CCHCR1 correlated with shorter disease-free survival. Six overlapping hub genes (CD8A, CDC20, E2F1, IL10, TNF, VCAM1) were overexpressed in GS 10 tumors, reflecting key pathways in tumor progression. Conclusions: GS 10 PC confers inferior time to BCR and displays a distinct genomic landscape compared to GS 8–9 disease, highlighting the need for biomarker-driven therapeutic strategies. Further studies are needed to validate these genomic targets and improve management for this very high-risk population. Full article

Human chemical carcinogenesis is a multistage process where chemicals or their metabolites cause irreversible changes in normal cell physiology, eventually leading to uncontrolled proliferation, transforming a normal cell into a cancerous one. Signal transducer and activator of transcription 3 (STAT3) is a cytoplasmic transcription factor that regulates cell proliferation, differentiation, apoptosis, angiogenesis, inflammation, and immune responses. Its aberrant activation triggers tumor progression by promoting the expression of oncogenic genes; thus, STAT3 is classified as an oncoprotein. The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that responds to a wide variety of chemicals, including carcinogens like dioxins, inducing genes associated with detoxification, proliferation, and immune regulation. Recent reports show that AhR plays a critical role in cancer development and maintenance. AhR may interact with signaling pathways, like the STAT3 pathway, which mediates the carcinogenic effects of several pollutants. Various chemical agents, such as industrial waste and hydrocarbon compounds, can alter the expression or signaling activity of AhR and STAT3 pathways, leading to different types of cancers. Understanding the complex STAT3-AhR network in the regulation of chemical carcinogenesis could open new avenues for cancer prevention or treatment, particularly in personalized medicine, aiming to improve life expectancy and achieving a complete cure. Full article

In the last decade, the aryl hydrocarbon receptor (AHR) has emerged as a critical peacekeeper for the maintenance of healthy skin. The evolutionary conservation of AHR implied physiological functions for this receptor, beyond the detoxification of man-made compounds, a notion further supported by the existence of physiological AHR ligands, notably derivates of tryptophan by the host and host microbiome. The UV light-derived ligand, 6-formylindolo[3,2-b]carbazole (FICZ), anticipated a role for AHR in skin, a UV light-exposed organ, where physiological AHR activation promotes a healthy skin barrier and constrains inflammation. The clinical development of tapinarof, the first topical AHR modulating drug for inflammatory skin disease, approved by the FDA for mild-to-moderate psoriasis and poised for approval in atopic dermatitis, supports the therapeutic targeting of the AHR pathway to harness its beneficial effect in skin inflammation. Here, we describe how a tightly controlled, physiological activation of the AHR pathway maintains skin homeostasis, and discuss how the pathway is dysregulated in psoriasis and atopic dermatitis, identifying areas offering opportunities for alternative therapeutic approaches, for further investigation. Full article

The highly contagious FMDV is the agent responsible for foot-and-mouth disease, significantly impacting animals with cloven hooves and incurring substantial economic losses globally. The FMDV genome, composed of single-stranded RNA, consists of approximately 8500 nucleotides and harbors a single open reading frame (ORF) encoding both structural and non-structural proteins vital for the virus’s pathogenicity and replication. BHK-21 (baby hamster kidney) cells are the optimal cell line for FMDV culture due to their robust viral replication ability and high infection susceptibility. The insufficient elucidation of the host response to FMDV hampers progress towards the establishment of precise therapeutic interventions. To fill this void in understanding, samples from FMDV-challenged and control BHK-21 cells were systematically procured, with comprehensive transcriptome sequencing subsequently undertaken to delineate the gene expression landscapes of each group. A total of 4018 differentially expressed genes were identified, of which 2044 were downregulated and 1974 were upregulated. The data indicate that FMDV infection significantly enhances transcription initiation in BHK-21. According to GO and KEGG enrichment analysis, FMDV affects a number of immune-related processes as well as the movement of chemicals within cells. In the analysis of the protein–protein interaction network, Fos, Flt3lg, Rpl22l1, Ifi35, Ep300, and Rps16 emerged as pivotal hub proteins, underscoring their significant roles within the cellular interactome. The RT-qPCR experiment of Lgfb5, Ler2, Vgll3, and Ahr verified that the DEGs’ expression profiles matched the results of the RNA-seq investigation. The study’s findings have enhanced our understanding of the molecular pathways underlying FMDV pathogenesis and host interactions. Furthermore, the identification of key genes could serve as potential targets for therapeutic strategies and diagnostic tools, thereby enhancing control measures for livestock foot-and-mouth disease and mitigating its economic impact. Full article

Nuclear receptors (NRs) are ligand-activated transcription factors that regulate a broad array of biological processes, including inflammation, lipid metabolism, cell proliferation, and apoptosis. Among the diverse family of NRs, peroxisome proliferator-activated receptors (PPARs), estrogen receptor (ER), liver X receptor (LXR), farnesoid X receptor (FXR), retinoid X receptor (RXR), and aryl hydrocarbon receptor (AhR) have garnered significant attention for their roles in neurodegenerative diseases, particularly Alzheimer’s disease (AD). NRs influence the pathophysiology of AD through mechanisms such as modulation of amyloid-beta (Aβ) deposition, regulation of inflammatory pathways, and improvement of neuronal function. However, the dual role of NRs in AD progression, where some receptors may exacerbate the disease while others offer therapeutic potential, presents a critical challenge for their application in AD treatment. This review explores the functional diversity of NRs, highlighting their involvement in AD-related processes and discussing the therapeutic prospects of NR-targeting strategies. Furthermore, the key challenges, including the necessity for the precise identification of beneficial NRs, detailed structural analysis through molecular dynamics simulations, and further investigation of NR mechanisms in AD, such as tau pathology and autophagy, are also discussed. Collectively, continued research is essential to clarify the role of NRs in AD, ultimately facilitating their potential use in the diagnosis, prevention, and treatment of AD. Full article