Arsenic exposure induces intestinal barrier damage and consequent activation of gut-liver axis leading to inflammation and pyroptosis of liver in ducks

Novel role of FTO in regulation of gut-brain communication via Desulfovibrio fairfieldensis-produced hydrogen sulfide under arsenic exposure

Fat mass and obesity-associated protein (FTO) is the key demethylase that reverses the abnormally altered N6-methyladenosine (m6A) modification in eukaryotic cells under environmental pollutants exposure. Arsenic is an environmental metalloid and can cause severe symptoms in human mainly through drinking water. However, there is no specific treatment for its toxic effects due to the uncovered mechanisms. We previously revealed that exposure to arsenic increased the level of m6A via down-regulation of FTO, which might serve as a potential target for intervention against arsenic-related disorders. In this study, our results demonstrated that chronic exposure to arsenic significantly disrupted the intestinal barrier and microenvironment. Also, this administration resulted in the enhancement of m6A modification and the reduction of FTO expression in the intestine. By using both CRISPR/Cas9-based FTO knock-in strategy and adeno-associated virus (AAV)-mediated overexpression of FTO in the intestine, we established for the first time that up-regulation of FTO remarkably ameliorated arsenic-induced disruption of intestinal barriers and altered microenvironment of mice. We also firstly identified a dominant gut microbial species, Desulfovibrio fairfieldensis, which was sharply reduced in arsenic-exposed mice, was able to proceed arsenic-induced neurobehavioral impairments by declining the levels of its major metabolite hydrogen sulfide. Administration of Desulfovibrio fairfieldensis could significantly alleviate the neurotoxicity of arsenic. Intriguingly, the beneficial effects of FTO against arsenic neurotoxicity possibly occurred through a novel gut-brain communication via Desulfovibrio fairfieldensis and its produced hydrogen sulfide. Collectively, these findings will provide new ideas for understanding the mechanisms of arsenic-induced toxic effects from a gut-brain communication perspective, and will assist the development of explicit intervention strategy via regulation of a new potential target FTO for prevention and treatment against arsenic-related both intestinal and neurological disorders.

Mn2O3 NPs-induced liver injury is potentially associated with gut microbiota dysbiosis in broiler chicken

Mn2O3 nanometer particles(Mn2O3 NPs), a new material, is widely used in medicine, electrochemical sensing and energy storage fields. The widespread use of Mn2O3 NPs has caused health concerns, and it is necessary to clarify the toxic mechanism of Mn2O3 NPs exposure. Our findings showed that Mn2O3 NPs exposure could lead to liver histological abnormalities, mitochondrial dysfunction in liver, as well as mitochondrial-mediated apoptosis, autophagy and mitochondrial dynamics disorder, and eventually lead to liver injury. At the same time, the ileal epithelium suffered physiological damage and inflammation after Mn2O3 NPs exposure, and the expression levels of genes and proteins related to intestinal barrier function (MUC1 ZO-1 Claudin1 and Occludin) were significantly down-regulated. Meanwhile, 16s sequencing analysis of intestinal bacteria showed that Mn2O3 NPs exposure caused significant changes in intestinal flora abundance. The Firmicutes/Bacteroidetes ratio increased, and the abundance of probiotics (Bacteroides, Bifidobacterium, Faecalibacterium) decreased, while the abundance of harmful bacteria (Streptococcus, Enterococcus, Pseudomonas) increased. The changes in these microflorae may potentially impact the development of liver injury. Altogether, these results provide novel insights into the potential mechanism of Mn2O3 NPs related hepatotoxicity induced by gut microbiota via the gut-liver axis, and contribute to a better interpretation of the health impact of Mn2O3 NPs.

Effects of minimal arsenic, lead, and cadmium exposure on biological pathways in Brazilian informal workers welding fashion jewelry

INTRODUCTION

This study complements previous research about informal workers occupational exposure by investigating the whole blood transcriptome of women engaged in informal home-based jewelry production in the city of Limeira, Sao Paulo, Brazil, focusing on associations between gene expression and arsenic (As), cadmium (Cd), and lead (Pb) concentrations in blood, as well as on identifying transcriptome profiles linked to self-reported health outcomes.

METHODS

Participants were divided into two groups: an exposed group comprising informal workers engaged in domestic jewelry welding activities (n = 22) and a control group composed of neighbors without occupational exposures (n = 19). Linear regression modeling assessed the association between the blood concentration of toxic elements, gene expression, and reported health outcomes. Pathway analysis was performed using ConsensusPathDB.

RESULTS

269 differentially expressed genes (DEGs) associated with As exposure and 43 with Cd exposure were found in this study, revealing significant health impacts on these workers. DEGs were also significantly associated with respiratory illness (bronchitis and asthma), neurological manifestations (sleep problems, migraines, or frequent headaches), shortness of breath, blood glucose, cholesterol, and triglyceride levels. Pathway analysis indicates genes related to inflammatory processes, alterations in intestinal permeability, and neurological outcomes.

CONCLUSION

The results shed light on the transcriptomic changes in this occupational context and contribute to a better understanding of the challenges faced by informal workers. Even with low doses of toxic elements in the blood, it was possible to observe differences in gene expression linked to self-reported outcomes. Additional studies should clarify the biological processes associated with toxic elements exposure.

Hexavalent chromium induces ferroptosis in small intestinal tissue of broilers through GPX4/HMGB1/p38-MAPK pathway

As a major environmental heavy metal pollutant, hexavalent chromium (Cr(VI)) causes irreversible damage to animals and humans. Nevertheless, how Cr(VI) exposure causes intestinal damage in broilers remains inadequately explored. This study explores Cr(VI)-induced poisoning using potassium dichromate to build a Cr(VI) poisoning model. The results indicate that Cr(VI) exposure evidently reduced the body weight and the functions of liver and kidney in broilers. Histopathological analysis revealed different degrees of structural damage in all three segments of the small intestines by Cr(VI) exposure. Moreover, Cr(VI) exposure downregulated ZO-1, Occludin, and Claudin-1, while altering the diversity of cecal microbiota to impair the intestinal barrier function. Additionally, with increasing Cr(VI) concentration, the contents of Fe2+, ROS, and LPO in all three intestinal segments showed a dose-dependent increase. The levels of GPX4, SLC7A11, FTL, and FTH1 were downregulated by Cr(VI), while the levels of p38-MAPK, phosphorylated p38, TFR1, and HMGB1 were upregulated. This study suggests that Cr(VI)-induced ROS can trigger ferroptosis through the GPX4/HMGB1/p38-MAPK pathway, leading to intestinal barrier dysfunction and ultimately reducing the production performance of broilers. This provides foundation of theory for understanding the effects of Cr(VI) exposure on the small intestine.

Comparative analysis of gut microbiota in healthy and diarrheic foals

Diarrhea presents a substantial risk of high morbidity and mortality among foals. Although studies have shown connections between gut microbiota and several gastrointestinal diseases, there is still inadequate information on gut microbial alterations in foals during diarrhea. In this study, we conducted 16S rRNA and ITS gene amplicon sequencing to investigate gut bacterial and fungal differences between healthy and diarrheic foals. The results unveiled significant reductions in gut bacterial and fungal diversities among foals experiencing diarrhea, accompanied by notable shifts in the composition of gut microbial communities. A considerable decrease was observed in the relative abundance of 30 bacterial and 34 fungal genera. Moreover, two bacterial and eight fungal genera were utterly undetectable in the gut microbiota of diarrheic foals. Some decreased genera, such as Bifidobacterium and Saccharomyces, were deemed beneficial and recognized as probiotics. The study revealed significant alterations in foals' gut bacterial and fungal communities during diarrhea, which enriched our comprehension of gut microbial dynamics in foals across varying health statuses. These findings offer valuable insights for managing diarrhea through gut microbiota modulation, suggesting that probiotics may be superior to antibiotics in preventing and controlling foal diarrhea.IMPORTANCEThis research advances the understanding of gut bacterial and fungal dynamics in foals, highlighting gut microbiota dysbiosis as a potential contributor to foal diarrhea. Additionally, we observed that many altered bacteria and fungi were downregulated during diarrhea, including some probiotic strains. Consequently, our findings provide evidence that probiotics may offer superior efficacy compared with antibiotics as potential candidates for preventing and treating foal diarrhea.

Protective Effects of Lactoferrin Treatment Against Sodium Arsenite Exposure-Induced Nephrotoxicity

It is said that a wide range of renal functions are at risk from arsenic exposure. We examined how lactoferrin administration may mitigate inflammation, apoptosis, redox imbalance, and fibrosis in order to counteract arsenic-induced nephrotoxicity. Accordingly, male C57BL/6 mice (6 weeks) were divided into six experimental groups with six mice in each group. The first and second groups were intragastrically administered normal saline and sodium arsenite (NaAsO2) at 5 mg/kg body weight concentrations as the negative control (NC) and NaAsO2 groups. The third, fourth, and fifth groups were intragastrically administered lactoferrin at concentrations of 100, 200, and 400 mg/kg body weight in addition to NaAsO2 at concentrations of 5 mg/kg body weight. The sixth group was intragastrically administered lactoferrin at a concentration of 200 mg/kg body weight with the experimental group set as the lactoferrin group. After daily drug administration for 4 weeks, the lactoferrin concentrations were optimized based on the results of renal index and renal function. Histopathological, biochemical, and gene expression analyses were performed to evaluate the status of renal tissue architecture, redox imbalance, inflammation, apoptosis, and fibrosis to confirm the alleviative effect of lactoferrin treatment against the NaAsO2 exposure-induced nephrotoxicity. The results confirmed that the 200 mg/kg lactoferrin treatment mitigated these arsenic effects and maintained the normal renal frameworks. Conclusively, disrupting the renal redox balance and triggering inflammation, apoptosis, along with fibrosis is a milieu that arsenic, robustly exerts its nephrotoxic effect. Lactoferrin, probably by its direct and indirect control mechanism on these said pathways, can mitigate the nephrotoxicity and preserve the normal renal health.

Selenomethionine Attenuates Aflatoxin B1-induced Liver Injury by Modulating the Gut Microbiota and Metabolites in Rabbits

Dietary contamination with aflatoxin B1 (AFB1), which can lead to severe liver damage, poses a great threat to livestock and poultry breeding and has detrimental impacts on food safety. Selenomethionine (SeMet), with anti-inflammatory, antioxidative, and detoxifying effects, is regarded as a beneficial food additive. However, whether SeMet can reduce AFB1-induced liver injury and intestinal microbial disorders in rabbits remains to be revealed. Forty 35-day-old rabbits were randomly divided into a control group, an AFB1 group, and 0.2 mg/kg Se and 0.4 mg/kg Se groups. The SeMet treatment group was fed different doses of the SeMet diet every day for 21 days. On Days 17-21, the AFB1 group, 0.2 mg/kg Se, and 0.4 mg/kg Se groups were intragastrically administered 0.3 mg AFB1/kg b.w. Results showed that SeMet restored alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, alleviating AFB1-induced liver function damage. This was linked to changes in intestinal metabolites and activation of the nuclear factor erythroid 2-related factor 2/heme oxygenase-1 (Nrf2/HO-1) pathway. In this study, the relationships between intestinal microorganisms and their metabolites and AFB1-induced liver injury are investigated, and the potential protective role of SeMet against liver damage induced by AFB1 offers novel insights into strategies for the prevention and treatment of AFB1-related toxicity.

The Role of miR-150-5p/SOCS1 Pathway in Arsenic-Induced Pyroptosis of LX-2 Cells

This study aims to explore the mechanism of pyroptosis of human hepatocyte LX-2 cells induced by NaAsO2 through the miR-150-5p/SOCS1 pathway. LX-2 cells were transfected with different concentrations of NaAsO2, miR-150-5p inhibitor, and SOCS1 agonist. Cell activity, cell pyroptosis, and the expression of related genes and proteins were detected by scanning electron microscopy, CCK-8, qRT-PCR, western blot, and immunofluorescence. Compared with the control group, 10 µmol/L and 20 µmol/L NaAsO2 significantly elevated the protein expression levels of the pyroptosis-related proteins NLRP3, GSDMD, GSDMD-N, caspase1, and cleaved caspase1 as well as the mRNA levels of NLRP3, GSDMD, caspase1, IL-18, and IL-1β. The typical pyroptosis with swelling and rupture of the plasma membrane was observed through scanning electron microscopy. The expression of miR-150-5p of the NaAsO2 intervention group increased, while the expression of SOCS1 decreased; then the level of NF-κB p65 elevated. With co-treatment of miR-150-5p inhibitor, SOCS1 agonist, and NaAsO2, the cell pyroptosis was attenuated, and the expressions of NLRP3, caspase1, GSDMD, GSDMD-N, IL-18, IL-1β, p65 of the group of miR-150-5p inhibitor and NaAsO2 group, and of the group of SOCS1 agonist and NaAsO2 reduced compared with the NaAsO2 group. Arsenic exposure promotes miR-150-5p, inhibits the expression of SOCS1, and activates the NF-κB/NLRP3 pathway in LX-2 cell pyroptosis.

Multi-omics elucidates the kidney damage caused by aquatic Cu via the gut-kidney axis in ducks

Copper (Cu) is an essential trace element for biological growth and development. Excessive intake of Cu exists harmful effects on organisms. However, whether excessive Cu intake induces kidney function damage by gut microbiota regulation remains unclear. Ducks are important species of waterfowl that are often exposed to Cu contamination in water sources. In this study, we aim to elucidate the effects of Cu exposure on renal inflammation through the gut-kidney axis in ducks. The ducks were gavaged with different doses of CuSO4 (0, 100, and 200 mg/kg body weight) for 4 weeks. Results indicate that Cu exposure causes pathological damage to the kidney, with a significant increase in the levels of TNFα, IL-6, and IL-1β in both serum and renal tissue. 16S rDNA analysis revealed that the relative abundances of Candidatus_Saccharimonas and Bacteroides were significantly reduced in the Cu-induced group. Transcriptomic analysis of kidney tissue reveals that following Cu exposure, 30 genes show significant differential expression. GO and KEGG enrichment analyses were most involved in Interleukin-1 Receptor Activity, Taurine and hypotaurine metabolism, Nitrogen metabolism, and Proximal tubule bicarbonate reclamation. Metabolomic analysis revealed that 28 metabolites are present in both kidney tissue and cecal contents. Correlation analysis revealed a strong correlation among 5 common metabolites: Aminoglutethimide, Boscalid, Dantrolene, Cer[ns] d34:1, and Stearidonic acid. In the cecum, these five metabolites are closely associated with 26 intestinal microorganisms, including Bacteroides, Candidatus_Saccharimonas, and Colidextribacter. In the kidney, apart from Stearidonic acid, the other four metabolites are closely correlated with genes such as FOS, and IL1RL1. Overall, our study indicates that excessive Cu induces significant kidney inflammation, the metabolites alteration and gut microbiota disorders. These findings shed light on the underlying mechanisms of Cu-induced kidney damage via the indirect pathway of the gut-kidney axis.

Impact of copper stress in the intestinal barriers and gut microbiota of Chinese stripe-necked turtle (Mauremys sinensis)

Copper is used to treat algal blooms, macrophyte infestations and other environmental issues, but its rising ambient levels harm aquatic animals, especially their intestines. However, its impact on turtles' digestive health is not well understood, and the risks are unclear. This study investigates the effects of copper on the intestinal health of Chinese stripe-necked turtle, focusing on histomorphology, mucosal barrier function, gene expression, and gut microbiota. Copper stress caused intestinal damage, characterized by shortened villi, inflammatory cell infiltration, and reduced epithelial layer thickness, as well as decreased acidic mucins, increased villi edema and inflammation. The mRNA expression level of bacteriostatic enzymes significantly reduced. Furthermore, This study found that copper exposure increases gut permeability by suppressing tight junction genes and triggers an inflammatory response in the gut, as indicated by elevated inflammatory cytokines. At the phylum level, Firmicutes exhibited a significant decrease, whereas Bacteroidota displayed a notable increase, and Fusobacteriota showed a substantial reduction in relative abundance in copper-treated groups. Similarly, at genus level Romboutsia, Cetobacterium decreased, while Turicibacter and Sarcina significantly increases in copper-treated groups compared to the control. This indicating the unique properties of copper including its essentiality, reactivity, and accumulation enables it to profoundly impact gut bacteria, altering both their composition and function. Copper's dual role as a nutrient and toxicant uniquely impacts gut microbes. Our findings suggest that copper stress compromises the intestinal physical, immune, chemical, and microbial barrier in M. sinensis, all of which contribute to the turtle's poor health.

Helicobacter pylori promotes intestinal flora imbalance and hepatic metabolic disorders under arsenic stress

Environmental arsenic contamination is a serious issue that cannot be ignored, since arsenic levels in drinking water frequently exceed safety standards, and there is an increased prevalence of Helicobacter pylori (H. pylori) infection. This results in an increasing population at risk of simultaneous exposure to both harmful agents, yet whether a synergistic interaction exists between them remains unclear. Therefore, this study aims to investigate the combined effects and underlying pathogenic mechanisms of concurrent exposure to these two hazardous factors by establishing a mouse model that is infected with H. pylori and exposed to inorganic arsenic through drinking water. Analysis of intestinal flora revealed significant alterations in the composition, relative abundance (Akkermansia, Faecalibaculum, Ilieibacterium, etc.), and metabolic potential of the intestinal microflora (amino acid metabolism and energy metabolism) in the combinatory exposure group. Non-targeted metabolomics analysis identified that the combinatory exposure group exhibited greater fluctuations in metabolite content, particularly in triacylglycerol, fatty-acid, peptide and amino acid. Moreover, H. pylori infection and arsenic exposure had increased levels of metabolites associated with the intestinal microbiota in their livers (4-Ethylphenyl sulfate and Phenylacetylglycine). Further analysis revealed significant correlations between changes in the intestinal flora and alterations in liver metabolic profiles. Herein, we hypothesize that H. pylori infection may exacerbate the intestinal flora imbalance and hepatic metabolic disturbances caused by arsenic exposure, which may disrupt enterohepatic homeostasis and potentially increase biological susceptibility to heavy metal toxicity.

Long-term copper exposure induced pyroptosis and inflammation of rat spleen through intestinal-splenic axis

Copper is an essential micro-element in animal growth. Tribasic copper chloride (TBCC), as an important source of animal feed copper, is widely used in agricultural production. Multiple studies have shown that excessive intake of copper can affect the immune function of animals and lead to disease or death. The intestine-spleen axis, which is the interaction between the spleen, intestines and gut microbiota, is closely linked to immune function in the body. However, the mechanism of intestine-spleen axis affecting TBCC induced immune dysfunction in rats has not been revealed. In this study, we analyzed the impacts of different doses of TBCC on the intestine, gut microbiota and spleen of rats, and investigated their relationship in the process. Our results demonstrated that under copper exposure, the structural integrity of the intestinal epithelium was compromised, resulting in a significant downregulation of genes and proteins expression levels related to the intestinal barrier (Zonula occludens-1, Claudin-1 and Occludin). Additionally, copper perturbed the composition of the rat intestinal microbiota, altered the abundance and diversity of the microbial community. Copper entered the spleen via the intestine-spleen axis, leading to structural damage in the spleen and activation of the NFκB signaling pathway, and increased pro-inflammatory cytokines (IFN-γ, TNF-α, IL-18, and IL-1β), ultimately causing pyroptosis and inflammation in the spleen. These findings offer a novel perspective on how copper may induce spleen injury through the intestine-spleen axis.

Dietary Iron Overload Triggers Hepatic Metabolic Disorders and Inflammation in Laying Hen

Iron, an essential trace element, is involved in various physiological processes; however, consumption of excessive iron possesses detrimental effects. In practical feed production, the iron content added to feeds often far exceeds the actual demand, resulting in an excess of iron in the body. The liver as a central regulator of iron homeostasis is susceptible to damage caused by disorders in iron metabolism. A model of hepatic iron overload in laying hens was developed in this study by incorporating iron into their diet, and the specific mechanisms underlying iron overload-induced hepatic injury were investigated. Firstly, this study revealed that a high-iron diet resulted in hepatic iron overload, accompanied by impaired liver function. Next, assessment of oxidative stress markers indicated a decrease in activities of T-SOD and CAT, coupled with an increase in MDA content, pointing to the iron-overloaded liver oxidative stress. Thirdly, the impact of iron overload on hepatic glycolipid and bile acid metabolism-related gene expressions were explored, including PPAR-α, GLUT2, and CYP7A1, highlighting disruptions in hepatic metabolism. Subsequently, analyses of inflammation-related genes such as iNOS and IL-1β at both protein and mRNA levels demonstrated the presence of inflammation in the liver under conditions of dietary iron overload. Overall, this study provided comprehensive evidence that dietary iron overload contributed to disorders in glycolipid and bile acid metabolism, accompanied by inflammatory responses in laying hens. Further detailing the specific pathways involved and the implications of these findings could offer valuable insights for future research and practical applications in poultry nutrition.

High-fat diet led to testicular inflammation and ferroptosis via dysbiosis of gut microbes

The disorder of gut microbiota has negative impact on male reproductive, and testicular damage is associated with obesity. However, the detailed mechanism of gut microbiota on the obesity-induced testis injury are still unknown. Therefore, we constructed a mouse model to investigate the effects of obesity on testis injury. In this study, we found that HFD-induced obesity could disorder gut microbiota homeostasis, which increased the abundance of Brevundimonas, Desulfovibrionaceae_unclassified and Ralstonia, ultimately leading to the overproduction of lipopolysaccharides (LPS). Meanwhile, HFD-feeding promoted intestinal permeability via inhibiting expression of tight junction proteins (ZO-1, Occludin and Claudin) and reducing excretion of mucus, leading to translocation of LPS. The over-accumulation of LPS in the bloodstream triggered an inflammatory response by activating TLR4/NF-κB pathway in testis. On the other hand, the gut microbiota produced-LPS also could induce ferroptosis in testis, as reflected by enhancing iron content and lipid peroxidation (MDA), as well as decreasing ferroptosis-related proteins, including GPX4, FTH1 and SLC1A11. Moreover, inhibition of LPS ligand (TLR4) with Resatorvid (TAK-242) alleviated obesity-induced testis injury through suppression of inflammation and ferroptosis. In conclusion, this study provides novel insights into the underlying mechanisms of obesity-related testis injury induced by gut microbiota disorder via the gut-testis axis, thus offering potential targets to counteract obesity-induced male reproductive disorder.

Mechanisms of Metal-Induced Hepatic Inflammation

PURPOSE OF REVIEW

Worldwide, there is an increasing prevalence of hepatic diseases. The most common diseases include alcoholic-associated liver disease (ALD), metabolic dysfunction-associated fatty liver disease/ metabolic dysfunction-associated steatohepatitis (MAFLD/MASH) and viral hepatitis. While there are many important mediators of these diseases, there is increasing recognition of the importance of the inflammatory immune response in hepatic disease pathogenesis.

RECENT FINDINGS

Hepatic inflammation triggers the onset and progression of liver diseases. Chronic and sustained inflammation can lead to fibrosis, then cirrhosis and eventually end-stage cancer, hepatocellular carcinoma. Importantly, growing evidence suggest that metal exposure plays a role in hepatic disease pathogenesis. While in recent years, studies have linked metal exposure and hepatic steatosis, studies emphasizing metal-induced hepatic inflammation are limited. Hepatic inflammation is an important hallmark of fatty liver disease. This review aims to summarize the mechanisms of arsenic (As), cadmium (Cd) and chromium (Cr)-induced hepatic inflammation as they contribute to hepatic toxicity and to identify data gaps for future investigation.

Arsenic trioxide induces innate immune response and inflammatory response in chicken liver via cGAS-STING/NF-κB pathway

Arsenic is a toxic metal-like element widely used in the pesticide, preservative and semiconductor industries. However, accumulation of arsenic through the food chain can cause serious damage to animal and human health. However, the toxic mechanism of arsenic-induced hepatotoxicity in chickens is not clear, and the present study aimed to investigate the potential role of cGAS-STING and NF-κB pathways on inflammatory injury in chicken liver. In this study, 75 white-feathered broilers were divided into a control group, a low-dose arsenic group (4 mg/kg) and a high-dose arsenic group (8 mg/kg) to investigate the toxic effects of arsenic on chicken liver. In this study, we found that pathological changes such as inflammatory cell infiltration and vesicular degeneration occurred in the liver when exposed to ATO. Crucially, exposure to ATO triggered the cGAS-STING pathway and markedly raised the levels of mRNA and protein expression of cGAS, STING, TBK1, and IRF7. The type I interferon response was also triggered. Simultaneously, STING induced the activation of the conventional NF-κB signaling pathway and stimulated the expression of genes associated with inflammation, such as IL-6, TNF-α and IL-1β. In summary, the induction of inflammatory responses via cGAS-STING and NF-κB signaling pathways under high ATO exposure provides new ideas for further studies on the toxicological mechanisms of arsenic.

Dietary administration of Bacillus subtilis improves the health parameters and regulates the gene expression in mice receiving zearalenone-contaminated diet

The biodegradation of mycotoxins has become a specific, efficient, and environmentally protective way to reduce the adverse effects of mycotoxins in both foods and feeds. In the current study, the effectiveness of dietary administration of Bacillus subtilis on health parameters and regulated gene expression in mice receiving zearalenone zearalenone-contaminated diet was explored. In this trial, a total of twenty-four white balb/c mice were randomly assigned to three treatments. Dietary treatments were as follows: T1: The control (fed non-zearalenone-contaminated diet), T2: fed zearalenone-contaminated diet, T3: fed zearalenone-contaminated diet + Bacillus subtilis ARKA-S-3 (1 × 109 cfu/kg) for 28 days. The results showed, B. subtilis notably degraded zearalenone in cultured media during 18 h incubation (p < 0.05). It significantly improved average daily weight gain and feed intake. Dietary B. subtilis notably reduced the adverse effects of zearalenone on serum antioxidant indices (GSH-Px, SOD, ) and saved mice from oxidative stress. Also, treatments with B. subtilis improved morphometric characteristics of the ileum ((Villus Height (µm), Villus Width (µm), and Crypt Depth (µm)) in the mice received zearalenone-contaminated diet (p < 0.05). The molecular analysis illustrated that B. subtilis has also improved the mRNA expression levels and antioxidant-related gene expression of SOD and CAT in the jejunum tissue. Moreover, it alleviated the IL-2 and IFN-γ gene profiling in the jejunum tissue. These findings illustrate that dietary administration of B. subtilis by having a degraded effect on zearalenone, possesses a protective effect on the health parameters and gene expression regulation in mice receiving a zearalenone-contaminated diet.

Arsenic-induced mtDNA release promotes inflammatory responses through cGAS-STING signaling in chicken hepatocytes

Arsenic is a toxic element that can cause severe liver damage in humans and animals. Arsenic-based inorganic pesticides, such as lead arsenate, copper arsenate, and calcium arsenate, are widely used for insect control and can eventually affect human health through accumulation in the food chain. However, the relationship between arsenic trioxide (ATO)-induced hepatotoxicity and the cGAS-STING signaling pathway has not been reported. The aim of this study was to investigate the potential role of inflammatory response in ATO-induced hepatotoxicity in chickens. In this study, we found that ATO exposure resulted in mtDNA leakage into the cytoplasm of chicken hepatocytes, which activated the cGAS-STING pathway and significantly increased the cGAS, STING, TBK1, and IRF7 mRNA and protein expression levels. Moreover, type I interferon response was activated. Concurrently, STING triggered the activation of the traditional NF-κB signaling pathway and promoted the expression of pro-inflammatory cytokine genes, including TNF-α, IL-6, and IL-1β. Subsequently, we found that both mtDNA clearance with EtBr and inhibition of the cGAS-STING pathway with H-151 reversed the ATO-induced innate immune and inflammatory responses. In summary, the above findings indicate that chicken hepatocytes can induce innate immune responses and inflammatory responses via mtDNA-cGAS-STING under ATO-exposure conditions, which is of great significance for further studies on the toxicity mechanism of ATO.

Ferulic Acid Inhibits Arsenic-Induced Colon Injury by Improving Intestinal Barrier Function

The prolonged exposure to arsenic results in intestinal barrier dysfunction, which is strongly concerned with detrimental processes such as oxidative stress and the inflammatory response. Ferulic acid (FA), as a phenolic acid, possesses the capability to mitigate arsenic-induced liver damage and cardiotoxic effects dependent on inhibition of oxidative stress and inflammatory responses. FA can mitigate testicular tissue damage and alveolar epithelial dysfunction, the mechanism of which may rely on nuclear factor erythroid 2-related factor 2/heme oxygenase 1 (Nrf2/HO-1) activation and nuclear factor-kappa B (NF-κB) pathway blocking. Based on the antioxidant and anti-inflammatory properties of FA, we speculated that FA might have the potential to inhibit arsenic-induced intestinal damage. To confirm this scientific hypothesis, mice exposed to sodium arsenite were treated with FA to observe colonic histopathology and TJ protein levels, and oxidative stress and TJ protein levels in Caco-2 cells exposed to sodium arsenite were assessed after FA intervention. In addition, molecular levels of NF-κB and Nrf2/HO-1 pathway in colon and Caco-2 cells were also detected. As shown in our data, FA inhibited arsenic-induced colon injury, which was reflected in the improvement of mucosal integrity, the decrease of down-regulated expression of tight junction (TJ) proteins (Claudin-1, Occludin, and ZO-1) and the inhibition of oxidative stress. Similarly, treatment with FA attenuated the inhibitory effect of arsenic on TJ protein expression in Caco-2 cells. In addition to suppressing the activation of NF-κB pathway, FA retrieved the activation of Nrf2/HO-1 pathway in colon and intestinal epithelial cells induced by arsenic. In summary, our findings propose that FA has the potential to mitigate arsenic-induced intestinal damage by preserving the integrity of intestinal epithelial TJs and suppressing oxidative stress. These results lay the groundwork for the potential use of FA in treating colon injuries caused by arsenic.

Exploring the effects of environmentally relevant concentrations of tris(2-chloroethyl) phosphate on tadpole health: A comprehensive analysis of intestinal microbiota and hepatic transcriptome

Tris(2-chloroethyl) phosphate (TCEP), a chlorinated organophosphate ester, is commonly found in aquatic environments. Due to its various toxic effects, it may pose a risk to the health of aquatic organisms. However, the potential impacts of TCEP exposure on the intestinal microbiota and hepatic function in amphibians have not been reported. This study investigated the impact of long-term exposure to environmentally relevant concentrations of TCEP (0, 3, and 90 μg/L) on the intestinal microbiota and hepatic transcriptome of Polypedates megacephalus tadpoles. The results showed that the body size of the tadpoles decreased significantly with an increase in TCEP concentration. Additionally, TCEP exposure affected the diversity and composition of the intestinal microbiota in tadpoles, leading to significant changes in the relative abundance of certain bacterial groups (the genera Aeromonas decreased and Citrobacter increased) and potentially promoting a more even distribution of microbial species, as indicated by a significant increase in the Simpson index. Moreover, the impact of TCEP on hepatic gene expression profiles in tadpoles was significant, with the majority of differentially expressed genes (DEGs) (709 out of 906 total DEGs in 3 μg/L of TCEP versus control, and 344 out of 387 DEGs in 90 μg/L of TCEP versus control) being significantly down-regulated, which were primarily related to immune response and immune system process. Notably, exposure to TCEP significantly reduced the relative abundance of the genera Aeromonas and Cetobacterium in the tadpole intestine. This reduction was positively correlated with the down-regulated expression of immune-related genes in the liver of corresponding tadpoles. In summary, these findings provide empirical evidence of the potential health risks to tadpoles exposed to TCEP at environmentally relevant concentrations.

Intestinal microbiota dysbiosis contributes to the liver damage in subchronic arsenic-exposed mice

There is an extensive amount of evidence that links changes in the intestinal microbiota structure to the progression and pathophysiology of many liver diseases. However, comprehensive analysis of gut flora dysbiosis in arsenic-induced hepatotoxicity is lacking. Herein, C57BL/6 mice are exposed to arsenic (1, 2, or 4 mg/kg) for 12 weeks, after which fecal microbiota transplantation (FMT) study is conducted to confirm the roles of the intestinal microbiome in pathology. Treatment with arsenic results in pathological and histological changes in the liver, such as inflammatory cell infiltration and decreased levels of TP and CHE but increased levels of ALP, GGT, TBA, AST, and ALT. Arsenic causes an increase in the relative abundance of Escherichia-Shigella, Klebsiella and Blautia, but a decrease in the relative abundance of Muribaculum and Lactobacillus. In arsenic-exposed mice, protein expressions of Occludin, ZO-1, and MUC2 are significantly decreased, but the level of FITC in serum is increased, and FITC fluorescence is extensively dispersed in the intestinal tract. Importantly, FMT experiments show that mice gavaged with stool from arsenic-treated mice exhibit severe inflammatory cell infiltration in liver tissues. Arsenic-manipulated gut microbiota transplantation markedly facilitates gut flora dysbiosis in the recipient mice, including an up-regulation in Escherichia-Shigella and Bacteroides, and a down-regulation in Lactobacillus and Desulfovibrio. In parallel with the intestinal microbiota wreck, protein expressions of Occludin, ZO-1, and MUC2 are decreased. Our findings suggest that subchronic exposure to arsenic can affect the homeostasis of the intestinal microbiota, induce intestinal barrier dysfunction, increase intestinal permeability, and cause damage to liver tissues in mice.

Arsenic-Induced Ferroptosis in Chicken Hepatocytes via the Mitochondrial ROS Pathway

Arsenic has been shown to be highly toxic and can cause liver damage. Previous studies have shown that arsenic causes severe liver damage and induces accumulation of reactive oxygen species (ROS). This study aimed to investigate the effects of ferroptosis on the liver in arsenic trioxide (ATO) and to explore the underlying mechanisms. We confirmed the hepatotoxic effects of arsenic by in vivo and in vitro experiments. After 28 days of administration of arsenic trioxide (4-mg/kg, 8-mg/kg) by gavage, chickens exhibited body weight loss and liver damage in a dose-dependent manner. In addition, in vivo and in vitro western blot and real-time fluorescence quantitative PCR analyses simultaneously indicated that ferroptosis might be the main pathway of arsenic-induced liver injury. Finally, Mito-TEMPO effectively eliminated the ROS accumulation in mitochondria, significantly attenuating the process of cellular ferroptosis. In summary, the hepatotoxic effects of arsenic are related to ferroptosis, and the hepatic ferroptosis process of arsenic is regulated by mitochondrial ROS (MtROS). Our study reveals new mechanisms of arsenic toxicity to the liver, which may deepen our understanding of arsenic toxicology.

Angiogenin-mediated tsRNAs control inflammation and metabolic disorder by regulating NLRP3 inflammasome

The cellular stress response system in immune cells plays a crucial role in regulating the development of inflammatory diseases. In response to cellular damage or microbial infection, the assembly of the NLRP3 inflammasome induces pyroptosis and the release of inflammatory cytokines. Meanwhile, Angiogenin (Ang)-mediated transfer RNA-derived small RNAs (tsRNAs) promote cell survival under stressful conditions. While both tsRNAs and inflammasomes are induced under stress conditions, the interplay between these two systems and their implications in regulating inflammatory diseases remains poorly understood. In this study, it was demonstrated that Ang deficiency exacerbated sodium arsenite-induced activation of NLRP3 inflammasome and pyroptosis. Moreover, Ang-induced 5'-tsRNAs inhibited NLRP3 inflammasome activation and pyroptosis. Mechanistically, 5'-tsRNAs recruit DDX3X protein into stress granules (SGs), consequently inhibiting the interaction between DDX3X and NLRP3, thus leading to the suppression of NLRP3 inflammasome activation. Furthermore, in vivo results showed that Ang deficiency led to the downregulation of tsRNAs, ultimately leading to an exacerbation of NLRP3 inflammasome-dependent inflammation, including lipopolysaccharide-induced systemic inflammation and type-2 diabetes-related inflammation. Altogether, our study sheds a new light on the role of Ang-induced 5'-tsRNAs in regulating NLRP3 inflammasome activation via SGs, and highlights tsRNAs as a promising target for the treatment of NLRP3 inflammasome-related diseases.

Arsenic exposure at environmentally relevant levels induced metabolic toxicity in development mice: Mechanistic insights from integrated transcriptome and metabolome

Emerging evidence has linked arsenic exposure and metabolic homeostasis, but the mechanism is incompletely understood, especially at relatively low concentrations. In this study, we used a mouse model to evaluate the health impacts and metabolic toxicity of arsenic exposure in drinking water at environmentally relevant levels (0.25 and 1.0 ppm). Our results indicated that arsenic damaged intestinal barrier and induced arsenic accumulation, oxidative stress, and pathological changes in the liver and illum. Interestingly, arsenic increased the hepatic triglyceride (TG) and total cholesterol (TC), while reduced serum TG and TC levels. The liver transcriptome found that arsenic exposure caused transcriptome perturbation and promoted hepatic lipid accumulation by regulating the exogenous fatty acids degradation and apolipoproteins related genes. The serum metabolomics identified 74 and 88 differential metabolites in 0.25 and 1.0 ppm, respectively. The KEGG disease and subcellular location analysis indicated that arsenic induced liver and intestinal diseases, and the mitochondrion might be the target organelle for arsenic-induced toxicity. Co-enrichment of transcriptome and metabolome identified 24 metabolites and 9 genes as metabolic toxicity biomarkers. Moreover, 40 male (20 nonalcoholic fatty liver disease (NAFLD) cases and 20 healthy controls) was further selected to validate our findings. Importantly, the significantly changed L-palmitoylcarnitine, 3-hydroxybutyric acid, 2-hydroxycaproic acid and 6 genes of Hadha, Acadl, Aldh3a2, Cpt1a, Cpt2, and Acox1 were found in the NAFLD cases. The results from integrated multi-omics and chemical-protein network analysis indicated that L-palmitoylcarnitine played a critical role in metabolic toxicity by regulating mitochondrial fatty acids β-oxidation genes (Cpt1a, Cpt2). In conclusion, these findings provided new clues for the metabolic toxicity of arsenic exposure at environmentally relevant levels, which involved in the late-life NAFLD development. Our results also contribute to understanding the human responses and phenotypic changes to this hazardous material exposure in the environment.

Mitochondrial miR-12294-5p-Regulated Copper Exposure-Caused Mitochondrial-Dependent Ferroptosis by Targeted Inhibition of CISD1 in Chicken Hepatocytes

Copper (Cu) is a common trace element additive in animal and human foods, and excessive intake of Cu has been shown to cause hepatotoxicity, but the underlying mechanism remains unclear. Our previous research found that Cu exposure dramatically upregulated mitochondrial miR-12294-5p expression and confirmed its targeted inhibition of CISD1 expression in chicken hepatocytes. Thus, we aimed to explore the potential role of mitomiR-12294-5p/CISD1 axis in Cu exposure-resulted hepatotoxicity. Here, we observed that Cu exposure resulted in Cu accumulation and pathological injury in chicken livers. Moreover, we found that Cu exposure caused mitochondrial-dependent ferroptosis in chicken hepatocytes, which were prominent on the increased mitochondrial Fe2+ and mitochondrial lipid peroxidation, inhibited levels of CISD1, GPX4, DHODH, and IDH2, and also enhanced level of PTGS2. Notably, we identified that inhibition of mitomiR-2954 level effectively mitigated Cu-exposure-resulted mitochondrial Fe2+ accumulation and mitochondrial lipid peroxidation and prevented the development of mitochondrial-dependent ferroptosis. However, increasing the mitomiR-12294-5p expression considerably aggravated the influence of Cu on these indicators. Meanwhile, the overexpression of CISD1 effectively alleviated Cu-caused mitochondrial-dependent ferroptosis, while silent CISD1 eliminated the therapeutic role of mitomiR-12294-5p inhibitor. Overall, our findings indicated that mitomiR-12294-5p/CISD1 axis played a critical function in Cu-caused hepatotoxicity in chickens by regulating mitochondrial-dependent ferroptosis.

Life cycle assessment of hepatotoxicity induced by cyhalofop-butyl in environmental concentrations on zebrafish in light of gut-liver axis

Cyhalofop-butyl (CB) poses a significant threat to aquatic organisms, but there is a discrepancy in evidence about hepatotoxicity after prolonged exposure to environmental levels. The aim of this study was to investigate long-term hepatotoxicity and its effects on the gut-liver axis through the exposure of zebrafish to environmental concentrations of CB (0.1,1,10 μg/L) throughout their life cycle. Zebrafish experienced abnormal obesity symptoms and organ index after a prolonged exposure of 120 days. The gut-liver axis was found to be damaged both morphologically and functionally through an analysis of histology, electron microscopy subcellular structure, and liver function. The disruption of the gut-liver axis inflammatory process by CB is suggested by the rise in inflammatory factors and the alteration of inflammatory genes. Furthermore, there was a noticeable alteration in the blood and gut-liver axis biochemical parameters as well as gene expression linked to lipid metabolism, which may led to an imbalance in the gut flora. In conclusion, the connection between the gut-liver axis, intestinal microbiota, and liver leads to the metabolic dysfunction of zebrafish exposed to long-term ambient concentrations of CB, and damaged immune system and liver lipid metabolism. This study gives another knowledge into the hepatotoxicity component of long haul openness to ecological centralization of CB, and might be useful to assess the potential natural and wellbeing dangers of aryloxyphenoxypropionate herbicides.

Cu exposure induces liver inflammation via regulating gut microbiota/LPS/liver TLR4 signaling axis

Copper (Cu) serves as an essential cofactor in all organisms, yet excessive Cu exposure is widely recognized for its role in inducing liver inflammation. However, the precise mechanism by which Cu triggers liver inflammation in ducks, particularly in relation to the interplay in gut microbiota regulation, has remained elusive. In this investigation, we sought to elucidate the impact of Cu exposure on liver inflammation through gut-liver axis in ducks. Our findings revealed that Cu exposure markedly elevated liver AST and ALT levels and induced liver inflammation through upregulating pro-inflammatory cytokines (IL-1β, IL-6 and TNF-α) and triggering the LPS/TLR4/NF-κB signaling pathway. Simultaneously, Cu exposure induced alterations in the composition of intestinal flora communities, notably increasing the relative abundance of Sphingobacterium, Campylobacter, Acinetobacter and reducing the relative abundance of Lactobacillus. Cu exposure significantly decreased the protein expression related to intestinal barrier (Occludin, Claudin-1 and ZO-1) and promoted the secretion of intestinal pro-inflammatory cytokines. Furthermore, correlation analysis was observed that intestinal microbiome and gut barrier induced by Cu were closely related to liver inflammation. Fecal microbiota transplantation (FMT) experiments further demonstrated the microbiota-depleted ducks transplanting fecal samples from Cu-exposed ducks disturbed the intestinal dysfunction, which lead to impaire liver function and activate the liver inflammation. Our study provided insights into the mechanism by which Cu exposure induced liver inflammation in ducks through the regulation of gut-liver axis. These results enhanced our comprehension of the potential mechanisms driving Cu-induced hepatotoxicity in avian species.

Inhibiting ferroptosis in brain microvascular endothelial cells: A potential strategy to mitigate polystyrene nanoplastics‒induced blood‒brain barrier dysfunction

Polystyrene nanoplastics (PS-NPs), a group of ubiquitous pollutants, may injure the central nervous system through the blood‒brain barrier (BBB). However, whether exposure to PS-NPs contributes to BBB disruption and the underlying mechanisms are still unclear. In vivo, we found that PS-NPs (25 mg/kg BW) could significantly increase BBB permeability in mice and downregulate the distribution of the tight junction-associated protein zona occludens 1 (ZO-1) in brain microvascular endothelial cells (BMECs). Using an in vitro BBB model, exposure to PS-NPs significantly reduced the transendothelial electrical resistance and altered ZO-1 expression and distribution in a dose-dependent manner. RNA-seq analysis and functional investigations were used to investigate the molecular pathways involved in the response to PS-NPs. The results revealed that the ferroptosis and glutathione metabolism signaling pathways were related to the disruption of the BBB model caused by the PS-NPs. PS-NPs treatment promoted ferroptosis in bEnd.3 cells by inducing disordered glutathione metabolism in addition to Fe2+ and lipid peroxide accumulation, while suppressing ferroptosis with ferrostatin-1 (Fer-1) suppressed ferroptosis-related changes in bEnd.3 cells subjected to PS-NPs. Importantly, Fer-1 alleviated the decrease in ZO-1 expression in bEnd.3 cells and the exacerbation of BBB damage induced by PS-NPs. Collectively, our findings suggest that inhibiting ferroptosis in BMECs may serve as a potential therapeutic target against BBB disruption induced by PS-NPs exposure.

Aspirin eugenol ester affects ileal barrier function, inflammatory response and microbiota in broilers under lipopolysaccharide-induced immune stress conditions

Aims

The aim of this study was to investigate the effects of aspirin eugenol ester (AEE) on ileal immune function in broilers under lipopolysaccharide (LPS)-induced immune stress.

Methods

Two hundred and forty one-day-old male Arbor Acres chicks were randomly divided into four groups (saline, LPS, saline + AEE and LPS + AEE) with six replicates of ten broilers each. The saline group and LPS group were fed the normal diet, while the other two groups received normal diet plus 0.1 g/kg AEE. Broilers in the LPS and LPS + AEE groups were injected intraperitoneally with 0.5 mg/kg B.W LPS in saline for seven consecutive days beginning at 14 days of age, while broilers in the saline and saline + AEE groups were injected with saline only.

Results

The results showed that AEE improved the ileal morphology and increased the ratio of villus height to crypt depth of immune-stressed broilers. LPS-induced immune stress significantly reduced the expression of the genes for the tight junction proteins occludin, zonula occludens-1 (ZO-1), claudin-1 and claudin-2, in the ileum, while AEE significantly up-regulated the expression of these genes. Compared with the saline group, the LPS-treated chickens showed significantly increased mRNA expression of the inflammatory factors tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6), interleukin-10 (IL-10), cyclooxygenase-2 (COX-2), and microsomal Prostaglandin E Synthesase-1 (mPGES-1) in the ileum, while they were significantly decreased by AEE supplementation. In addition, analysis of the ileal bacterial composition showed that compared with saline and LPS + AEE groups, the proportion of Firmicutes and Lactobacillus in the LPS group was lower, while the proportion of Proteobacteria and Escherichia-Shigella was higher. Similarly, Line Discriminant Analysis Effect Size (LEfSe) analysis showed that compared with the LPS group, Brevibacillus was dominant in the saline group, while the LPS + AEE group was rich in Rhizobium, Lachnoclostridium, Ruminococcaceae, Faecalibacterium, Negativibacillus, Oscillospiraceae, and Flavonifractor.

Conclusion

These results indicate that dietary supplementation with 0.1 g/kg AEE could protect the intestinal health by improving the intestinal villus morphology, enhancing the expression of tight junction genes and alleviating inflammation to resist the immune stress caused by LPS stimulation in broilers, and the mechanism may involve COX-2-related signal transduction and improved intestinal microbiota composition.

The effects of heavy metal exposure on brain and gut microbiota: A systematic review of animal studies

The gut-brain axis is a crucial interface between the central nervous system and the gut microbiota. Recent evidence shows that exposure to environmental contaminants, such as heavy metals, can cause dysbiosis in gut microbiota, which may affect the gut-brain communication, impacting aspects of brain function and behavior. This systematic review of the literature aims to evaluate whether deleterious effects on brain function due to heavy metal exposure could be mediated by changes in the gut microbiota profile. Animal studies involving exposure to heavy metals and a comparison with a control group that evaluated neuropsychological outcomes and/or molecular outcomes along with the analysis of microbiota composition were reviewed. The authors independently assessed studies for inclusion, extracted data and assessed risk of bias using the protocol of Systematic Review Center for Laboratory Animal Experimentation (SYRCLE) for preclinical studies. A search in 3 databases yielded 16 eligible studies focused on lead (n = 10), cadmium (n = 1), mercury (n = 3), manganese (n = 1), and combined exposure of lead and manganese (n = 1). The animal species were rats (n = 7), mice (n = 4), zebrafish (n = 3), carp (n = 1) and fruit fly (n = 1). Heavy metals were found to adversely affect cognitive function, behavior, and neuronal morphology. Moreover, heavy metal exposure was associated with changes in the abundance of specific bacterial phyla, such as Firmicutes and Proteobacteria, which play crucial roles in gut health. In some studies, these alterations were correlated with learning and memory impairments and mood disorders. The interplay of heavy metals, gut microbiota, and brain suggests that heavy metals can induce direct brain alterations and indirect effects through the microbiota, contributing to neurotoxicity and the development of neuropsychological disorders. However, the small number of papers under review makes it difficult to draw definitive conclusions. Further research is warranted to unravel the underlying mechanisms and evaluate the translational implications for human health.

Co-exposure of arsenic and polystyrene-nanoplastics induced kidney injury by disrupting mitochondrial homeostasis and mtROS-mediated ferritinophagy and ferroptosis

Arsenic (As) and polystyrene nanoplastics (PSNPs) co-exposure induced biotoxicity and ecological risks have attracted wide attention. However, the combined effects of As and PSNPs on the kidney and their underlying mechanisms of toxicities remain to be explored. Here, we investigated the effects of As and PSNPs co-exposure on structure and function in mice kidney, and further explored the possible mechanisms. In this study, we identified that co-exposure to As and PSNPs exhibited conspicuous renal structural damage and pathological changes, accompanied by renal tissue fibrosis (increased protein expression of Collagen I and α-SMA and deposition of collagen fibers), whereas alone exposure to As or PSNPs does not exhibit nephrotoxicity. Subsequently, our results further showed that combined action of As and PSNPs induced mitochondrial oxidative damage and impaired mitochondrial dynamic balance. Furthermore, co-treatment with As and PSNPs activated NCOA4-mediated ferritinophagy and ferroptosis in mice kidney and TCMK-1 cells, which was confirmed by the changes in the expression of ferritinophagy and ferroptosis related indicators (NCOA4, LC3, ATG5, ATG7, FTH1, FTL, GPX4, SLC7A11, FSP1, ACSL4 and PTGS2). Meaningfully, pretreatment with the mtROS-targeted scavenger Mito-TEMPO significantly attenuated As and PSNPs co-exposure induced mitochondrial damage, ferritinophagy and ferroptosis. In conclusion, these findings demonstrated that mtROS-dependent ferritinophagy and ferroptosis are important factors in As and PSNPs co-exposure induced kidney injury and fibrosis. This study provides a new insight into the study of combined toxicity of nanoplastics and heavy metal pollutants.

Decreased Arsenic Disposition and Alteration of its Metabolic Profile in mice Coexposed to Fluoride

Inorganic arsenic (iAs) and fluoride (iF) are ubiquitous elements whose coexistence is frequent in several regions of the world due to the natural contamination of water sources destined for human consumption. It has been reported that coexposure to these two elements in water can cause toxic effects on health, which are controversial since antagonistic and synergistic effects have been reported. However, there is little information on the possible toxicological interaction between concurrent exposure to iAs and iF on the iAs metabolism profile.The goal of this study was to determine the effect of iF exposure on iAs methylation patterns in the urine and the tissues of female mice of the C57BL/6 strain, which were divided into four groups and exposed daily for 10 days through drinking water as follows: purified water (control); arsenite 1 mg/L, fluoride 50 mg/L and arsenite & fluoride 1:50 mg/L.To characterize the iAs methylation pattern in concomitant iF exposure, iAs and its methylated metabolites (MAs and DMAs) were quantified in the tissues and the urine of mice was exposed to iAs alone or in combination. Our results showed a statistically significant decrease in the arsenic species concentrations and altered relative proportions of arsenic species in tissues and urine in the As-iF coexposure group compared to the iAs-exposed group. These findings show that iF exposure decreases arsenic disposition and alters methylation capacity.Nevertheless, additional studies are required to elucidate the mechanisms involved in the iAs-iF interaction through iF exposure affecting iAs disposition and metabolism.

Long-term Cu exposure alters CYP450s activity and induces jejunum injury and apoptosis in broilers

Copper (Cu) is an essential trace element that plays a crucial role in numerous physiopathological processes related to human and animal health. In the poultry industry, Cu is used to promote growth as a feed supplement, but excessive use can lead to toxicity on animals. Cytochrome P450 enzymes (CYP450s) are a superfamily of proteins that require heme as a cofactor and are essential for the metabolism of xenobiotic compounds. The purpose of this study was to explore the influence of exposure to Cu on CYP450s activity and apoptosis in the jejunum of broilers. Hence, we first simulated the Cu exposure model by feeding chickens diets containing different amounts of Cu. In the present study, histopathological observations have revealed morphological damage to the jejunum. The expression levels of genes and proteins of intestinal barrier markers were prominently downregulated. While the mRNA expression level of the gene associated with CYP450s was significantly increased. Additionally, apoptosis-related genes and proteins (Bak1, Bax, Caspase-9, Caspase-3, and CytC) were also significantly augmented by excessive Cu, while simultaneously decreasing the expression of Bcl-2. It can be concluded that long-term Cu exposure affects CYP450s activity, disrupts intestinal barrier function, and causes apoptosis in broilers that ultimately leads to jejunum damage.

Associations of arsenic exposure and arsenic metabolism with the risk of non-alcoholic fatty liver disease

Growing evidences supported that arsenic exposure contributes to non-alcoholic fatty liver disease (NAFLD) risk, but findings were still inconsistent. Additionally, once absorbed, arsenic is methylated into monomethyl and dimethyl arsenicals. However, no studies investigated the association of arsenic metabolism with NAFLD. Our objectives were to evaluate the associations of arsenic exposure and arsenic metabolism with NAFLD prevalence. We conducted a case-control study with 1790 participants derived from Dongfeng-Tongji cohort and measured arsenic species (arsenite, arsenate, monomethylarsonate [MMA], dimethylarsinate [DMA], and arsenobetaine) in urine. Arsenic exposure (∑As) was defined as the sum of inorganic arsenic (iAs), MMA, and DMA. Arsenic metabolism was evaluated as the proportions of inorganic-related species (iAs%, MMA%, and DMA%) and methylation efficiency ratios (primary methylation index [PMI], secondary methylation index [SMI]). NAFLD was diagnosed by liver ultrasound. Logistic regression was used to evaluate the associations. The median of ∑As was 13.24 μg/g creatinine. The ∑As showed positive and nonlinear association with moderate/severe NAFLD (OR: per log-SD = 1.33, 95% CI: [1.03,1.71]; Pfor nonlinearity = 0.021). The iAs% (OR: per SD = 1.16, 95% CI: [1.03,1.30]) and SMI (OR: per log-SD = 1.16, 95% CI: [1.03,1.31]) showed positive while MMA% (OR: per SD = 0.80, 95% CI: [0.70,0.91]) and PMI (OR: per log-SD = 0.86, 95% CI: [0.77,0.96]) showed inverse associations with NAFLD. Moreover, the ORs (95% CI) of NAFLD for each 5% increase in iAs% was 1.36 (1.17,1.58) when MMA% decreased and 1.07 (1.01,1.13) when DMA% decreased; and for each 5% increase in MMA%, it was 0.74 (0.63,0.86) and 0.79 (0.69,0.91) when iAs% and DMA% decreased, respectively. The results suggest that inorganic arsenic exposure is positively associated with NAFLD risk and arsenic methylation efficiency plays a role in the NAFLD. The findings provide clues to explore potential interventions for the prevention of NAFLD. Prospective studies are needed to validate our findings.

Chronic arsenic exposure affects stromal cells and signaling in the small intestine in a sex-specific manner

Arsenic is a toxicant that is ingested through drinking water and food, exposing nearly 140 million people to levels above the 10 ppb guideline concentration. Studies have shown that arsenic affects intestinal stem cells (ISCs), but the mechanisms by which arsenic alters the formation of adult cells in the small intestine are not well understood. Signals derived from intestinal stromal cells initiate and maintain differentiation. The goal of this study is to evaluate arsenic's effect on intestinal stromal cells, including PdgfrαLo trophocytes, located proximal to the ISCs, and PdgfrαHi telocytes, located proximal to the transit-amplifying region and up the villi. Adult Sox9tm2Crm-EGFP mice were exposed to 0, 33, and 100 ppb sodium arsenite in their drinking water for 13 weeks, and sections of duodenum were examined. Flow cytometry indicated that arsenic exposure dose-responsively reduced Sox9+ epithelial cells and trended toward increased Pdgfrα+ cells. The trophocyte marker, CD81, was reduced by 10-fold and 9.0-fold in the 100 ppb exposure group in male and female mice, respectively. Additionally, a significant 2.2- to 3.1-fold increase in PdgfrαLo expression was found in male mice in trophocytes and Igfbp5+ cells. PdgfrαHi protein expression, a telocyte marker, was more prevalent along the villus/crypt structure in females, whereas Gli1 expression (telocytes) was reduced in male mice exposed to arsenic. Principle coordinate analysis confirmed the sex-dependent response to arsenic exposure, with an increase in trophocyte and decrease in telocyte marker expression observed in male mice. These results imply that arsenic alters intestinal mesenchymal cells in a sex-dependent manner.

Maternal F-53B exposure during pregnancy and lactation induced glucolipid metabolism disorders and adverse pregnancy outcomes by disturbing gut microbiota in mice

In the metal plating industry, F-53B has been widely used for almost half a century as a replacement for perfluorooctane sulfonate. However, F-53B can reach the food chain and affect human health. Pregnant women have distinct physiological characteristics and may thus be more sensitive to the toxicity of F-53B. In the present study, F-53B was added to the drinking water of pregnant mice during gestation and lactation at doses of 0 mg/L (Ctrl), 0.57 mg/L (L-F), and 5.7 mg/L (H-F). The aim was to explore the potential effects of F-53B on glucolipid metabolism and pregnancy outcomes in dams. Results showed that F-53B induced disordered glucolipid metabolism, adverse pregnancy outcomes, hepatic inflammation, oxidative stress and substantially altered related biochemical parameters in maternal mice. Moreover, F-53B induced remarkable gut barrier damage and gut microbiota perturbation. Correlation analysis revealed that gut microbiota is associated with glucolipid metabolism disorders and hepatic inflammation. The fecal microbiota transplant experiment demonstrated that altered gut microbiota induced by F-53B caused metabolic disorders, adverse pregnancy outcomes, and gut barrier damage. These results suggested that maternal mice exposed to F-53B during gestation and lactation had an increased risk of developing metabolic disorders and adverse pregnancy outcomes and highlighted the crucial role of the gut microbiota in this process, offering novel insights into the risk of F-53B to health.

Co-exposure ochratoxin A and triadimefon influenced the hepatic glucolipid metabolism and intestinal micro-environment in mice

Ochratoxin A (OTA) is a mycotoxin, and triadimefon (TDF) is a triazole fungicide. These compounds are prevalent in the environment, and their residues have been detected in crops. However, the precise health risks associated with mycotoxins and fungicides are not fully elucidated. In this work, five-week-old mice were gavage with OTA (0.3 and 1.5 mg/kg/day), TDF (10 and 50 mg/kg/day), and OTA + TDF (0.3 + 10 and 1.5 + 50 mg/kg/day) for 28 days. Exposure to OTA, TDF, and OTA + TDF led to significant alterations in liver total cholesterol (TC), triglyceride (TG), and glucose (GLU) levels, as well as in genes associated with glycolipid metabolism in mice. Reduced acylcarnitine levels in serum indicated that OTA, TDF, and co-exposure inhibited fatty acid (FA) β-oxidation. Furthermore, OTA and TDF disrupted the integrality of the gut barrier function and altered the structure of the intestinal microbiota. These findings suggested that OTA, TDF, and their co-exposure might disrupt the intestinal barrier, alter the structure of the microbiota, and subsequently inhibit FA β-oxidation, indicating the interference of OTA and TDF with glycolipid-related intestinal barrier dysfunction. Moreover, our data revealed a toxic additive effect between OTA and TDF, providing a foundation for assessing the combined toxicity risk of mycotoxins and fungicides.

Egg Yolk Lipids Alleviated Dextran Sulfate Sodium-Induced Colitis by Inhibiting NLRP3 Inflammasome and Regulating Gut Microbiota

The increasing incidence of inflammatory bowel disease (IBD) has become a global phenomenon. Egg yolk lipids are one of the essential dietary foods, but its effects on intestinal immunity remain unclear. Here, egg yolk lipids are obtained using ethanol extraction and a total of 601 kinds of lipids are detected via lipidomics, including 251 kinds of triglycerides, 133 kinds of phosphatidylcholines, 44 kinds of phosphatidylethanolamines. Then, the study finds that egg yolk lipids significantly alleviate dextran sulfate sodium-induced colitis and reduce the production of inflammatory factors. Meanwhile, egg yolk lipids also maintain intestinal barrier integrity and decrease lipopolysaccharide translocation by alleviating intestinal structure damage and increasing the numbers of goblet cells and mucin 2. Mechanistically, egg yolk lipids attenuate colitis by inhibiting the assembly and activation of NLRP3 inflammasome. Moreover, the study also finds that egg yolk lipids reverse gut microbiota dysbiosis referring to increased relative abundance of Bacteroides acidifaciens and decrease relative abundance of Akkermansia muciniphila, as well as increased short chain fatty acids concentration in the gut. Together, the study elucidates the anti-colitis effect of egg yolk lipids and provides positive evidences for egg yolk lipids involving in dietary strategy and IBD therapy.

Physiological and microbiome adaptation of coral Turbinaria peltata in response to marine heatwaves

Against the backdrop of global warming, marine heatwaves are projected to become increasingly intense and frequent. This trend poses a potential threat to the survival of corals and the maintenance of entire coral reef ecosystems. Despite extensive evidence for the resilience of corals to heat stress, their ability to withstand repeated heatwave events has not been determined. In this study, we examined the responses and resilience of Turbinaria peltata to repeated exposure to marine heatwaves, with a focus on physiological parameters and symbiotic microorganisms. In the first heatwave, from a physiological perspective, T. peltata showed decreases in the Chl a content and endosymbiont density and significant increases in GST, caspase-3, CAT, and SOD levels (p < .05), while the effects of repeated exposure on heatwaves were weaker than those of the initial exposure. In terms of bacteria, the abundance of Leptospira, with the potential for pathogenicity and intracellular parasitism, increased significantly during the initial exposure. Beneficial bacteria, such as Achromobacter arsenitoxydans and Halomonas desiderata increased significantly during re-exposure to the heatwave. Overall, these results indicate that T. peltata might adapt to marine heatwaves through physiological regulation and microbial community alterations.

Arsenic and polystyrene-nano plastics co-exposure induced testicular toxicity: Triggers oxidative stress and promotes apoptosis and inflammation in mice

Co-existing of polystyrene-nano plastics (PSNPs) and arsenic (As) in the environment caused a horrendous risk to human health. However, the potential mechanism of PSNPs and As combination induced testicular toxicity in mammals has not been elucidated. Therefore, we first explore the testicular toxicity and the potential mechanism in male Kunming mice exposed to As or/and PSNPs. Results revealed that compared to the As or PSNPs group, the combined group showed more significant testicular toxicity. Specifically, As and PSNPs combination induced irregular spermatozoa array and blood-testis barrier disruption. Simultaneously, As and PSNPs co-exposure also exacerbated oxidative stress, including increasing the MDA content, and down-regulating expression of Nrf-2, HO-1, SOD-1, and Trx. PSNPs and As combination also triggered testicular apoptosis, containing changes in apoptotic factors (P53, Bax, Bcl-2, Cytc, Caspase-8, Caspase-9, and Caspase-3). Furthermore, co-exposed to As and PSNPs aggravated inflammatory damage characterized by targeted phosphorylation of NF-κB and degradation of I-κB. In summary, our results strongly confirmed As + PSNPs co-exposure induced the synergistic toxicity of testis through excessive oxidative stress, apoptosis, and inflammation, which could offer a new sight into the mechanism of environmental pollutants co-exposure induced male reproductive toxicity.

Dietary modulation of gut microbiota affects susceptibility to drug-induced liver injury

The rising incidence of drug-induced liver injury (DILI) parallels contemporary dietary shifts that have transformed the composition of human gut microbiota. The relationship between these phenomena remains unknown. Here, it is unveiled that a high fiber diet (HFiD) provides substantial protection against DILI, whereas a western style diet (WSD) significantly exacerbates DILI. Gut microbiota transplantation further confirms these differing outcomes are mediated by diet-induced variations in gut microbiota. Mechanistically, Lactobacillus acidophilus, enriched by HFiD, alleviates DILI through its metabolite indole-3-lactic acid (ILA), which activates the AhR/Nrf2 signaling pathway, thus enhancing hepatocellular antioxidant defenses and detoxification capacity. In the clinical intervention of subjects with prediabetes (N = 330), dietary fiber intervention enriches intestinal L. acidophilus, elevates serum ILA levels, and improves liver function. Conversely, WSD induces disturbance in bile acid metabolism and dysbiosis in gut microbiota, which impairs the intestinal barrier and facilitates the translocation of lipopolysaccharides (LPS) to the liver, thus triggering inflammatory responses and exacerbating DILI. These results demonstrate that dietary patterns significantly influence the onset of DILI by modulating gut microbiota. This novel insight expands the understanding of DILI risk factors and highlights the potential of dietary modifications as a preventive strategy against DILI.

NaAsO2 regulates TLR4/MyD88/NF-κB signaling pathway through DNMT1/SOCS1 to cause apoptosis and inflammation in hepatic BRL-3A cells

The exact molecular mechanism of arsenic-induced liver injury has not been fully elucidated. The aim of the study was to investigate the potential mechanism of NaAsO2-induced cytotoxicity in BRL-3A cells and to provide a basis for the mechanism of arsenic poisoning. BRL-3A cells were treated with different doses of NaAsO2, DNMT1 inhibitor (DC_517), TLR4 inhibitor (TAK-242), and transfection of SOCS1 plasmid. Cell activity, apoptosis, inflammation and protein expression of DNMT1, SOCS1, TLR4, MyD88, and NF-κB were detected by CCK8 assay, Annexin V-FITC and Western blot, respectively. With increasing NaAsO2 doses, BAX and caspase-3 expression increased, Bcl-2 expression decreased, pro-inflammatory factors TNF-α, IL-1β, and IL-6 increased, and cell activity decreased causing increased apoptosis. When BRL-3A was intervened with 10, and 20 μmol/L NaAsO2, DNMT1 expression was elevated, SOCS1 expression was decreased, and TLR4, MyD88, p-IκBα/IκBα, and p-p65/p65 expression were elevated. After the combination of NaAsO2 and DC_517, compared to the NaAsO2 group, apoptosis and inflammation were attenuated, SOCS1 expression was elevated and TLR4, MyD88, p-IκBα/IκBα and p-p65/p65 expression was decreased. Apoptosis and inflammation were attenuated after co-treatment of SOCS1 high expression with NaAsO2 compared to the NaAsO2 group. In addition, TLR4, MyD88, p-IκBα/IκBα and p-p65/p65 expression was reduced. When NaAsO2 and TAK-242 were combined, apoptosis and inflammation were attenuated. Besides MyD88, p-IκBα/IκBα and p-p65/p65 expression was reduced compared to the NaAsO2 group. We found that NaAsO2 induce apoptosis and inflammation in BLR-3A cells, which may be related to inhibit SOCS1 through regulation of DNMT1 and thus activating the TLR4/MyD88/NF-κB signaling pathway.

Arsenic induced neurotoxicity in the brain of ducks: The potential involvement of the gut-brain axis

BACKGROUND

Arsenic is a widely distributed ecotoxic pollutant that has been found to cause neurotoxicity in a variety of species. Gut-brain axis is a two-way information network between the gut microbiome and the brain, which is closely related to organismal health. However, the role of the gut-brain axis in arsenic-induced neurotoxicity remains largely unknown.

METHODS

In order to explore whether there is a relationship between brain and gut microbiota of meat ducks, we performed molecular biological detection including RT-qPCR and Western blot, as well as morphological detection including, HE staining and immunohistochemistry. Meanwhile, intestinal contents were analyzed using 16 S ribosomal RNA gene sequencing and analysis RESULTS: In this study, we investigated whether arsenic trioxide (ATO) can activate the gut microbiome-brain axis to induce intestinal and brain injury. The results showed that ATO-exposure disrupted the diversity balance of intestinal microbiota and integrity and injured the intestinal structure. ATO-exposure also reduced the number of glycogen and goblet cells in the duodenum. In addition, exposure to ATO caused intestinal inflammatory injury by activating NF-κB signaling pathway and promoting the expression of its target genes. Meanwhile, the tight junction-related proteins (ZO-1, occludin) of gut and brain were reduced by ATO exposure. Furthermore, results also revealed that ATO-exposure induced brain injury, including neuronal cell vacuolization and reduced numbers of neuronal cells in the cortex and hippocampus. Remarkably, ATO-exposure also disrupted neurotransmitter levels. Additionally, our further molecular mechanism study revealed that ATO-exposure increased the expression of autophagy and apoptosis related mRNA and proteins levels in the brain tissues.

CONCLUSION

Altogether, these findings provide a new insight into that ATO-exposure induced intestinal injury and aggravated neurotoxicity via the gut-brain axis.

Toxic vascular effects of polystyrene microplastic exposure

Polystyrene microplastics (PSMPs) are some of the most common microplastic components, and the resulting pollution has become a global problem. Extensive studies have been conducted on the toxic effects of PSMPs on the heart, lungs, liver, kidneys, nerves, intestines and other tissues. However, the impact of PSMPs on vascular toxicity is poorly understood at present. The aim of this study was to reveal the vascular toxicity of microplastics (MPs). Patients were assigned to a calcification group (25 patients) or a non-calcification group (22 patients) based on the presence or absence of calcification in the thoracic aorta wall. We detected 7 polymer types in human feces. Patients with vascular calcification (VC) had higher levels of total MPs, polypropylene (PP) and polystyrene (PS) in feces than patients without VC. The thoracic aortic calcification score was significantly positively correlated with the total MP abundance (Spearman r = 0.8109, p < 0.0001), PP (Spearman r = 0.7211, p = 0.0160) and PS (Spearman r = 0.6523, p = 0.0471) in feces. We then explored the effects of PSMP exposure on normal and vitamin D3 + nicotine (VDN)-treated rats. PSMP exposure induced mild VC in normal rats and aggravated VC in VDN-treated rats. PSMP exposure disturbed the gut microbiota, causing Proteobacteria and Escherichia_Shigella to be the dominant phylum and genus, respectively. It also induced intestinal inflammatory responses in normal rats, aggravated intestinal inflammation in VDN-treated rats, impaired the intestinal mucosal barrier, and increased intestinal permeability. This study provides a theoretical basis for the risk assessment of MP-induced cardiovascular disease.

Paeoniflorin recued hepatotoxicity under zinc oxide nanoparticles exposure via regulation on gut-liver axis and reversal of pyroptosis

The risks of Zinc oxide nanoparticles (ZnO NPs) applications in biological medicine, food processing industry, agricultural production and the biotoxicity brought by environmental invasion of ZnO NPs both gradually troubled the public due to the lack of research on detoxification strategies. TFEB-regulated autophagy-pyroptosis pathways were found as the crux of the hepatotoxicity induced by ZnO NPs in our latest study. Here, our study served as a connecting link between preceding toxic target and the following protection mechanism of Paeoniflorin (PF). According to a combined analysis of network pharmacology/molecular docking-intestinal microbiota-metabolomics first developed in our study, PF alleviated the hepatotoxicity of ZnO NPs from multiple aspects. The hepatic inflammatory injury and hepatocyte pyroptosis in mice liver exposed to ZnO NPs was significantly inhibited by PF. And the intestinal microbiota disorder and liver metabolic disturbance were rescued. The targets predicted by bioinformatics and the signal trend in subacute toxicological model exhibited the protectiveness of PF related to the SIRT1-mTOR-TFEB pathway. These evidences clarified multiple protective mechanisms of PF which provided a novel detoxification approach against ZnO NPs, and further provided a strategy for the medicinal value development of PF.

Gut microbiota-related metabolite alpha-linolenic acid mitigates intestinal inflammation induced by oral infection with Toxoplasma gondii

BACKGROUND

Oral infection with cysts is the main transmission route of Toxoplasma gondii (T. gondii), which leads to lethal intestinal inflammation. It has been widely recognized that T. gondii infection alters the composition and metabolism of the gut microbiota, thereby affecting the progression of toxoplasmosis. However, the potential mechanisms remain unclear. In our previous study, there was a decrease in the severity of toxoplasmosis after T. gondii α-amylase (α-AMY) was knocked out. Here, we established mouse models of ME49 and Δα-amy cyst infection and then took advantage of 16S rRNA gene sequencing and metabolomics analysis to identify specific gut microbiota-related metabolites that mitigate T. gondii-induced intestinal inflammation and analyzed the underlying mechanism.

RESULTS

There were significant differences in the intestinal inflammation between ME49 cyst- and Δα-amy cyst-infected mice, and transferring feces from mice infected with Δα-amy cysts into antibiotic-treated mice mitigated colitis caused by T. gondii infection. 16S rRNA gene sequencing showed that the relative abundances of gut bacteria, such as Lactobacillus and Bacteroides, Bifidobacterium, [Prevotella], Paraprevotella and Macellibacteroides, were enriched in mice challenged with Δα-amy cysts. Spearman correlation analysis between gut microbiota and metabolites indicated that some fatty acids, including azelaic acid, suberic acid, alpha-linolenic acid (ALA), and citramalic acid, were highly positively correlated with the identified bacterial genera. Both oral administration of ALA and fecal microbiota transplantation (FMT) decreased the expression of pro-inflammatory cytokines and restrained the MyD88/NF-κB pathway, which mitigated colitis and ultimately improved host survival. Furthermore, transferring feces from mice treated with ALA reshaped the colonization of beneficial bacteria, such as Enterobacteriaceae, Proteobacteria, Shigella, Lactobacillus, and Enterococcus.

CONCLUSIONS

The present findings demonstrate that the host gut microbiota is closely associated with the severity of T. gondii infection. We provide the first evidence that ALA can alleviate T. gondii-induced colitis by improving the dysregulation of the host gut microbiota and suppressing the production of pro-inflammatory cytokines via the MyD88/NF-κB pathway. Our study provides new insight into the medical application of ALA for the treatment of lethal intestinal inflammation caused by Toxoplasma infection. Video Abstract.

Dissecting the role of cadmium, lead, arsenic, and mercury in non-alcoholic fatty liver disease and non-alcoholic steatohepatitis

The objective of the present study was to review the existing epidemiological and laboratory findings supporting the role of toxic metal exposure in non-alcoholic fatty liver disease (NAFLD). The existing epidemiological studies demonstrate that cadmium (Cd), lead (Pb), arsenic (As), and mercury (Hg) exposure was associated both with an increased risk of NAFLD and altered biochemical markers of liver injury. Laboratory studies demonstrated that metal exposure induces hepatic lipid accumulation resulting from activation of lipogenesis and inhibition of fatty acid β-oxidation due to up-regulation of sterol regulatory element-binding protein 1 (SREBP-1), carbohydrate response element binding protein (ChREBP), peroxisome proliferator-activated receptor γ (PPARγ), and down-regulation of PPARα. Other metabolic pathways involved in this effect may include activation of reactive oxygen species (ROS)/extracellular signal-regulated kinase (ERK) and inhibition of AMP-activated protein kinase (AMPK) signaling. The mechanisms of hepatocyte damage during development of metal-induced hepatic steatosis were shown to involve oxidative stress, endoplasmic reticulum stress, pyroptosis, ferroptosis, and dysregulation of autophagy. Induction of inflammatory response contributing to progression of NAFLD to non-alcoholic steatohepatitis (NASH) upon toxic metal exposure was shown to be mediated by up-regulation of nuclear factor κB (NF-κB) and activation of NRLP3 inflammasome. Moreover, epigenetic effects of the metals, as well as their effect on gut microbiota and gut wall integrity were also shown to mediate their role in NAFLD development. Despite being demonstrated for Cd, Pb, and As, the contribution of these mechanisms into Hg-induced NAFLD is yet to be estimated. Therefore, further studies are required to clarify the intimate mechanisms underlying the relationship between heavy metal and metalloid exposure and NAFLD/NASH to reveal the potential targets for treatment and prevention of metal-induced NAFLD.

Paternal lipopolysaccharide exposure induced intrauterine growth restriction via the inactivation of placental MEST/PI3K/AKT pathway in mice

Maternal lipopolysaccharide (LPS) exposure during pregnancy has been related to IUGR. Here, we explored whether paternal LPS exposure before mating impaired fetal development. All male mice except controls were intraperitoneally injected with LPS every other day for a total of five injections. The next day after the last LPS, male mice were mated with untreated female mice. Interestingly, fetal weight and crown-rump length were reduced, while the incidence of IUGR was increased in paternal LPS exposure group. Additionally, paternal LPS exposure leaded to poor placental development through causing cell proliferation inhibition and apoptosis. Additional experiment demonstrated that the inactivation of placental PI3K/AKT pathway might be involved in paternal LPS-induced cell proliferation inhibition and apoptosis of trophoblast cells. Furthermore, the mRNA and protein levels of mesoderm specific transcript (MEST), a maternally imprinted gene with paternal expression, were significantly decreased in mouse placentas from paternal LPS exposure. Further analysis showed that paternal LPS exposure caused the inactivation of placental PI3K/AKT pathway and then cell proliferation inhibition and apoptosis might be via down-regulating placental MEST. Overall, our results provide evidence that paternal LPS exposure causes poor placental development and subsequently IUGR may be via down-regulating MEST/PI3K/AKT pathway, and then inducing cell proliferation inhibition and apoptosis in placentas.

Interplay of Extracellular Vesicles and TLR4 Signaling in Hepatocellular Carcinoma Pathophysiology and Therapeutics

Hepatocellular carcinoma (HCC) stands as a significant contributor to global cancer-related mortality. Chronic inflammation, often arising from diverse sources such as viral hepatitis, alcohol misuse, nonalcoholic fatty liver disease (NAFLD), and nonalcoholic steatohepatitis (NASH), profoundly influences HCC development. Within this context, the interplay of extracellular vesicles (EVs) gains prominence. EVs, encompassing exosomes and microvesicles, mediate cell-to-cell communication and cargo transfer, impacting various biological processes, including inflammation and cancer progression. Toll-like receptor 4 (TLR4), a key sentinel of the innate immune system, recognizes both pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs), thereby triggering diverse signaling cascades and pro-inflammatory cytokine release. The intricate involvement of the TLR4 signaling pathway in chronic liver disease and HCC pathogenesis is discussed in this study. Moreover, we delve into the therapeutic potential of modulating the TLR4 pathway using EVs as novel therapeutic agents for HCC. This review underscores the multifaceted role of EVs in the context of HCC and proposes innovative avenues for targeted interventions against this formidable disease.

Sodium humate alleviates LPS-induced intestinal barrier injury by improving intestinal immune function and regulating gut microbiota

Sodium humate (HNa), known for its abundant functional active groups, is extensively utilized in food dietary supplements due to its versatile properties. Furthermore, HNa possesses notable anti-inflammatory, antioxidant, and anti-diarrheal properties. This research endeavor aimed to elucidate the protective effects of HNa against intestinal barrier injury induced by lipopolysaccharide (LPS). The findings of this study demonstrated that pretreatment with HNa effectively mitigated intestinal barrier injury in the jejunum. HNa exhibited inhibitory effects on the activation of the NLRP3 inflammasome and the production of inflammatory factors within the intestine. HNa supplementation also contributed to the upregulation of mucin and tight junctions (TJs) expression, consequently enhancing the integrity of the intestinal barrier. Notably, our investigation revealed that HNa shared comparable efficacy with the TLR4 inhibitor TAK-242 in inhibiting the TLR4/NFκB signaling pathway. Furthermore, an in-depth analysis of the gut microbiota demonstrated that HNa exerted a regulatory influence on LPS-induced microflora disturbance. In conclusion, these findings collectively indicate that HNa mitigates LPS-induced mucosal damage in the jejunum and preserves the integrity of the intestinal barrier by modulating intestinal immune function and regulating gut microbiota.