Exposure to dibutyl phthalate impairs lipid metabolism and causes inflammation via disturbing microbiota-related gut-liver axis

Associations between pre- and post-natal exposure to phthalate and DINCH metabolites and gut microbiota in one-year old children

The gut microbiota is a collection of symbiotic microorganisms in the gastrointestinal tract. Its sensitivity to chemicals with widespread exposure, such as phthalates, is little known. We aimed to investigate the impact of perinatal exposure to phthalates on the infant gut microbiota at 12 months of age. Within SEPAGES cohort (Suivi de l'Exposition à la Pollution Atmosphérique durant la Grossesse et Effet sur la Santé), we assessed 13 phthalate metabolites and 2 di(isononyl) cyclohexane-1,2-dicarboxylate (DINCH) metabolites in repeated urine samples collected in pregnant women and their offspring. We obtained stool samples from 356 children at 12 months of age and sequenced the V3-V4 region of the 16S rRNA gene, allowing gut bacterial profiling. We used single-chemical (linear regressions) and mixture (BKMR, Bayesian Kernel Machine Regression) models to examine associations of phthalates and DINCH metabolites, with gut microbiota indices of α-diversity (specific richness and Shannon diversity) and the relative abundances of the most abundant microbiota phyla and genera. After correction for multiple testing, di(2-ethylhexyl) phthalate (ΣDEHP), diethyl phthalate (DEP) and bis(2-propylheptyl) phthalate (DPHP) metabolites 12-month urinary concentrations were associated with higher Shannon α-diversity of the child gut microbiota in single-chemical models. The multiple-chemical model (BKMR) suggested higher α-diversity with exposure to the phthalate mixture at 12 months, driven by the same phthalates. There were no associations between phthalate and DINCH exposure biomarkers at other time points and α-diversity after correction for multiple testing. ΣDEHP metabolites concentration at 12 months was associated with higher Coprococcus genus. Finally, ΣDEHP exposure at 12 months tended to be associated with higher phylum Firmicutes, an association not maintained after correction for multiple testing. Infancy exposure to phthalate might disrupt children's gut microbiota. The observed associations were cross-sectional, so that reverse causality cannot be excluded.

Diethyl ethylphosphonate retardants disturbed the gut microbiome and metabolite SCFAs in vitro based on simulator of the human intestinal microbial ecosystem

Diethyl ethylphosphonate (DEEP) as a novel organophosphorus flame retardant received increasing attention and its structure was discovered. But there are currently insufficient studies on how DEEP exposure affects the gut microbiome. In this study, the effects of DEEP on the structure and function of the human gut microbiota were examined using the SHIME system. Results from high-throughput sequencing of the 16S rRNA gene show that the high dose DEEP exposure reduced the Shannon and Simpson index in the transverse and descending colon. The Bacillota had the highest proportion while the proportion of Proteobacteria gradually decreased at the phylum level. The abundance of Escherichia, Prevotella, and Bilophila at the genus level increased with increasing doses of DEEP exposure. On the contrary, the abundance of Megasphaera, Klebsiella, and Phascolarctobacterium decreased. The short-chain fatty acids had a significant shift. With increasing doses of DEEP exposure, the concentration of acetic acid and propionic acid increased, while the concentration of butyric acid reached the highest at the medium dose of exposure. In addition, Bilophila, Psychrobacter, Escherichia, and Nostoe showed strong beneficial associations with acetic and propionic acids under DEEP exposure. Phocaeicola, Agathobacter, Klebsiella, Megasphaera, Phascolarctobacterium, and Bacteroides were negatively association with acetic and propionic acids. In a word, the study verified that exposure to different doses of DEEP can cause changes in the composition of the gut microbiome and metabolite SCFAs, which provides ideas for the investigation of other potential hazards of DEEP on human beings.

Multi-Omics Analysis of the Molecular Mechanisms by Which Extract of Artemisia selengensis Turcz. Ameliorates DBP-Induced Liver Injury

Artemisia selengensis Turcz. is a perennial herb belonging to the genus Artemisia in the family Asteraceae. Known for its nutrient richness, distinct flavor, and medicinal properties, Artemisia selengensis Turcz. has garnered attention. However, its efficacy, particularly in alleviating hepatic injury, remains underexplored. This study aims to assess the therapeutic potential of the 50% ethanol extract of Artemisia selengensis Turcz. (ASTE) in a mouse model of dibutyl phthalate (DBP)-induced liver injury. Through multi-omics analysis, including transcriptomics, metabolomics, and intestinal flora examination, we explored the pathways and key targets of ASTE in treating liver injury. Network pharmacology further identified the crucial components of ASTE for liver injury treatment. Our findings indicate that ASTE affects intestinal flora such as Adlercreutzia through flavonoids, particularly naringin and epicatechin. Additionally, key genes in the PPAR pathway, such as fatty acid-binding protein 3 (Fabp3), fatty acid-binding protein 5 (Fabp5), 3-hydroxyacyl-CoA dehydrogenase (Ehhadh), and phospholipid transfer protein (Pltp), influence glycerophospholipid metabolism, contributing to liver injury amelioration. This study sheds light on the molecular mechanisms underlying ASTE's hepatoprotective effects, laying the groundwork for its potential application as a functional food.

Female rat liver after sub-acute dibutyl phthalate treatment: Histological, stereological, biochemical, and global gene expression study

Although it has been recognized that females are more susceptible to chemical-induced liver injury, the effects of dibutyl phthalate (DBP), a widely used synthetic chemical, on female liver structure and function are under-researched. Here, we sought to investigate the effects of DBP on histological, stereological, and biochemical parameters, as well as global gene expression in female rat liver. Female Wistar rats were exposed to 100, 500, and 5000 mg DBP/kg diet for 28 days, corresponding to 8.6, 41.43, and 447.33 mg DBP/kg body weight (B.W.)/day, respectively. The highest dose (447.33 mg DBP/kg B.W./day) was between the no-observed-adverse-effect level (NOAEL) and the lowest-observed-adverse-effect level for liver toxicity, whereas two lower doses (8.6 and 41.43 mg DBP/kg B.W./day) were below the NOAEL. Analysis of hematoxylin and eosin-stained sections revealed an increased volume of hepatocytes, their nuclei and cytoplasm, while the volume of sinusoids decreased in DBP-exposed groups compared to the control. Examination of Periodic acid-Schiff-stained sections showed reduced glycogen content, which was the most prominent in the highest dose group. Increased glutathione S-transferase and catalase activities, and decreased GSH content and superoxide dismutase activity were observed in DBP-exposed groups. The mRNA sequencing revealed DBP-induced dose-specific changes in various genes and biological functions in female rat liver. The highest number of deregulated genes was observed in the 500 mg DBP/kg diet group. In summary, exposure to DBP caused significant liver microstructural changes, decreased glycogen content, disturbed the redox status, and affected global gene expression in female rat liver.

Persistent effects of di-n-butyl phthalate on liver transcriptome: Impaired energy and lipid metabolic pathways

The environmental contaminant dibutyl phthalate (DBP) is reported to be hepatotoxic, but the underlying molecular pathways and pathological processes remain unclear. Here we used RNA-sequencing to characterize persistent hepatic transcriptional effects one week after the conclusion of five weeks oral exposure to 10 mg/kg/day or 100 mg/kg/day DBP in adult male mice. The exploratory transcriptome analysis demonstrated five differentially expressed genes (DEGs) in the 10 mg/kg/day group and 13 in the 100 mg/kg/day group. Gene Set Enrichment Analysis (GSEA), which identifies affected biological pathways rather than focusing solely on individual genes, revealed nine significantly enriched Reactome pathways shared by both DBP treatment groups. Additionally, we found 54 upregulated and one downregulated Reactome pathways in the 10 mg/kg/day DBP group, and 29 upregulated and 13 downregulated pathways in the 100 mg/kg/day DBP group. DBP exposure disrupted several key biological processes, including protein translation, protein folding, apoptosis, Hedgehog signaling, degradation of extracellular matrix and alterations in the energy/lipid metabolism. Subsequent liver tissue analysis confirmed that DBP exposure induced tissue disorganization, oxidative stress, lipid accumulation, increased TNF-α, ATP and glucokinase levels, and affected key metabolic proteins, predominantly in a dose-response manner. Overall, the results show that DBP can cause hepatic stress and damage and suggest a potential role for DBP in the development of non-alcoholic fatty liver disease, the most prevalent liver disease worldwide.

Exploring Gut–Brain Interaction Disorders: Mechanisms and Translational Therapies Crossing Neurology to Gastroenterology

The bidirectional communication network between the gut and the brain, known as the gut–brain axis, plays a crucial role in health and disease. This review explores the mechanisms underlying gut–brain interaction disorders and highlights translational therapies bridging neurology and gastroenterology. Mechanisms encompass anatomical, endocrine, humoral, metabolic, and immune pathways, with the gut microbiota exerting profound influence. Clinical evidence links gut microbiota fluctuations to mood disorders, GI disruptions, and neurodevelopmental conditions, emphasizing the microbiome’s pivotal role in shaping brain–gut interactions. Pharmacological therapies such as amitriptyline and selective serotonin reuptake inhibitors modulate neurotransmitter activity, offering relief in functional gastrointestinal disorders like irritable bowel syndrome (IBS). Non-pharmacological interventions like cognitive–behavioral therapy and hypnotherapy address maladaptive thoughts and induce relaxation, alleviating gastrointestinal symptoms exacerbated by stress. Emerging therapies include gut microbiota modulation, dietary interventions, vagus nerve stimulation, and intestinal barrier modulation, offering novel approaches to manage neurological disorders via the gastrointestinal tract. Understanding and harnessing the gut–brain axis holds promise for personalized therapeutic strategies in neurogastroenterology.

Dibutyl phthalate (DBP) promotes Epithelial-Mesenchymal Transition (EMT) to aggravate liver fibrosis into cirrhosis and portal hypertension (PHT) via ROS/TGF-β1/Snail-1 signalling pathway in adult rats

OBJECTIVE

The primary objective of this study was to investigate the toxicological impact of Dibutyl phthalate (DBP) on the process of liver fibrosis transitioning into cirrhosis and the subsequent development of portal hypertension (PHT) through the mechanism of epithelial-mesenchymal transition (EMT) mediated by the ROS/TGF-β/Snail-1 signaling pathway.

METHOD

Carbon tetrachloride (CCl4) (1 mg/kg) was introduced in adult rats by oral feeding in CCl4 and CCl4+DBP groups twice a week for 8 weeks, and twice for another 8 week in CCl4 group. DBP was introduced by oral feeding in the CCl4+DBP group twice over the following 8 weeks. We subsequently analyzed hemodynamics measurements and liver cirrhosis degree, hepatic inflammation and liver function in the different groups. EMT related genes expression in rats in the groups of Control, DBP, CCl4 and CCl4+DBP were measured by immunohistochemistry (IHC). Enzyme-linked immunosorbent Assay (ELISA), qRT-PCR, western blot were used to detect the EMT related proteins and mRNA gene expression levels in rats and primary hepatocytes (PHCs). Reactive oxygen species (ROS) were examined with a ROS detection kit.

RESULTS

The results showed that the CCl4+DBP group had higher portal pressure (PP) and lower mean arterial pressure (MAP) than the other groups. Elevated collagen deposition, profibrotic factor, inflammation, EMT levels were detected in DBP and CCl4+DBP groups. ROS, TGF-β1 and Snail-1 were highly expressed after DBP exposure in vitro. TGF-β1 had the potential to regulate Snail-1, and both of them were subject to regulation by ROS.

CONCLUSION

DBP could influence the progression of EMT through its toxicological effect by ROS/TGF-β1/Snail-1 signalling pathway, causing cirrhosis and PHT in final. The findings of this research might contribute to a novel comprehension of the underlying toxicological mechanisms and animal model involved in the progression of cirrhosis and PHT, and potentially offered a promising therapeutic target for the treatment of the disease.

Micro(nano)plastics and Their Potential Impact on Human Gut Health: A Narrative Review

Microplastics and nanoplastics (MNPs) are becoming an increasingly severe global problem due to their widespread distribution and complex impact on living organisms. Apart from their environmental impact, the effects of MNPs on living organisms have also continued to attract attention. The harmful impact of MNPs has been extensively documented in marine invertebrates and larger marine vertebrates like fish. However, the research on the toxicity of these particles on mammals is still limited, and their possible effects on humans are poorly understood. Considering that MNPs are commonly found in food or food packaging, humans are primarily exposed to them through ingestion. It would be valuable to investigate the potential harmful effects of these particles on gut health. This review focuses on recent research exploring the toxicological impacts of micro- and nanoplastics on the gut, as observed in human cell lines and mammalian models. Available data from various studies indicate that the accumulation of MNPs in mammalian models and human cells may result in adverse consequences, in terms of epithelial toxicity, immune toxicity, and the disruption of the gut microbiota. The paper also discusses the current research limitations and prospects in this field, aiming to provide a scientific basis and reference for further studies on the toxic mechanisms of micro- and nanoplastics.

Noxious ramifications of cosmetic pollutants on gastrointestinal microbiome: A pathway to neurological disorders

On exposure to cosmetic pollutants, gastrointestinal dysbiosis, which is characterised by a disturbance in the gut microbiota, has come into focus as a possible contributor to the occurrence of neurotoxic consequences. It is normal practice to use personal care products that include parabens, phthalates, sulphates, triclosans/triclocarbans and micro/nano plastics. These substances have been found in a variety of bodily fluids and tissues, demonstrating their systemic dispersion. Being exposed to these cosmetic pollutants has been linked in recent research to neurotoxicity, including cognitive decline and neurodevelopmental problems. A vital part of sustaining gut health and general well-being is the gut flora. Increased intestinal permeability, persistent inflammation, and impaired metabolism may result from disruption of the gut microbial environment, which may in turn contribute to neurotoxicity. The link between gastrointestinal dysbiosis and the neurotoxic effects brought on by cosmetic pollutants may be explained by a number of processes, primarily the gut-brain axis. For the purpose of creating preventative and therapeutic measures, it is crucial to comprehend the intricate interactions involving cosmetic pollutants, gastrointestinal dysbiosis, and neurotoxicity. This review provides an in-depth understanding of the various hazardous cosmetic pollutants and its potential role in the occurrence of neurological disorders via gastrointestinal dysbiosis, providing insights into various described and hypothetical mechanisms regarding the complex toxic effects of these industrial pollutants.

An insight into the critical role of gut microbiota in triggering the phthalate-induced toxicity and its mitigation using probiotics

Exposure to phthalates, a major food safety concern, has been implicated in various chronic human disorders. As dietary exposure serves as a primary exposure route for phthalate exposure, understanding the detrimental impact on the gastrointestinal tract and resident gut microbiota is indispensable for better managing public health risks. Various reports have explored the intricate interplay between phthalate exposure, gut microbiota dysbiosis and host pathophysiology. For instance, oral exposure of dibutyl phthalate (DBP) or di-(2-ethylhexyl) phthalate (DEHP) affected the Firmicutes/Bacteroidetes ratio and abundance of Akkermansia and Prevotella, ensuing impaired lipid metabolism and reproductive toxicity. In some cases, DEHP exposure altered the levels of gut microbial metabolites, namely short-chain fatty acids, branched-chain amino acids or p-cresol, resulting in cholesterol imbalance or neurodevelopmental disorders. Conversely, supplementation of gut-modulating probiotics like Lactococcus or Lactobacillus sp. averted the phthalate-induced hepatic or testicular toxicity through host gene regulation, gut microbial modulation or elimination of DEHP or DBP in faeces. Overall, the current review revealed the critical role of the gut microbiota in initiating or exacerbating phthalate-induced toxicity, which could be averted or mitigated by probiotics supplementation. Future studies should focus on identifying high-efficiency probiotic strains that could help reduce the exposure of phthalates in animals and humans.

The intestinal microbiota as mediators between dietary contaminants and host health

The gut microbiota sit at an important interface between the host and the environment, and are exposed to a multitude of nutritive and non-nutritive substances. These microbiota are critical to maintaining host health, but their supportive roles may be compromised in response to endogenous compounds. Numerous non-nutritive substances are introduced through contaminated foods, with three common groups of contaminants being bisphenols, phthalates, and mycotoxins. The former contaminants are commonly introduced through food and/or beverages packaged in plastic, while mycotoxins contaminate various crops used to feed livestock and humans alike. Each group of contaminants have been shown to shift microbial communities following exposure; however, specific patterns in microbial responses have yet to be identified, and little is known about the capacity of the microbiota to metabolize these contaminants. This review characterizes the state of existing research related to gut microbial responses to and biotransformation of bisphenols, phthalates, and mycotoxins. Collectively, we highlight the need to identify consistent, contaminant-specific responses in microbial shifts, whether these community alterations are a result of contaminant effects on the host or microbiota directly, and to identify the extent of contaminant biotransformation by microbiota, including if these transformations occur in physiologically relevant contexts.

Dibutyl phthalate induces liver fibrosis via p38MAPK/NF-κB/NLRP3-mediated pyroptosis

Dibutyl phthalate (DBP) is one of the most employed plasticizers pervading the environment. DBP is a newly identified global organic pollutant that can activate NLRP3 inflammasomes and induce inflammatory liver injury. However, its hepatotoxicity remains poorly understood. The objective of this investigation was to investigate the probable pathways underlying DBP-induced liver injury. First, C57BL/6N mice were orally administered DBP at 10 and 50 mg/kg B.W. doses for 28 days. The observed results indicated a significant increase in liver collagen deposition and upregulated protein expression of fibrosis markers in mice. In addition, the p38MAPK/NF-κB signaling pathway and pyroptosis-related protein expression were upregulated. To establish a correlation between these changes, we conducted a conditioned medium co-culture of human hepatocellular carcinoma (HepG2) and human hepatic stellate (LX-2) cells. We performed inhibitor interventions to validate the mechanism of DBP-induced liver fibrosis in vitro. After treatment with p38MAPK (SB203580), NF-κB (PDTC), and NLRP3 (MCC950) inhibitors, the activation of LX-2 cells, the p38MAPK/NF-κB signaling pathway and pyroptosis due to DBP were alleviated. Therefore, DBP exposure leads to NLRP3-mediated pyroptosis of hepatocytes via the p38MAPK/NF-κB signaling pathway, activating LX-2 cells and causing liver fibrosis. Our findings offer a conceptual framework to understand the pathological underpinnings of DBP-induced liver injury while proposing novel ideas to prevent and treat DBP hepatotoxicity. Thus, targeting p38MAPK, NF-κB, and NLRP3 may prevent DBP-induced liver fibrosis.

Combined cytotoxicity of phthalate esters on HepG2 cells: A comprehensive analysis of transcriptomics and metabolomics

Phthalate esters (PAEs), widely used as plasticizers, may pose a potential environmental and human hazard. The aim of this study was to compare the cytotoxicity of di(2-ethylhexyl) phthalates (DEHP) and dibutyl phthalate (DBP)) after their exposure to HepG2 cells alone or in combination. HepG2 cells treated with individual/combined DEHP and DBP at a dose of 10-2 M for 24 h were selected for metabolome and transcriptome analysis. The results demonstrated that exposure to the mixtures of DEHP and DBP caused enhanced or reduced toxic effects regarding 8 pathways with 1065 downregulated genes and 643 upregulated genes, in comparison with those of single chemicals. The combined toxicity of mixture revealed both synergistic and antagonistic interactions between DEHP and DBP. Besides, combined exposure to DEHP and DBP promoted TCA cycle, pyrimidine, and purine metabolism, while an antagonistic effect on fatty acid derangement should require further investigation. To summarize, our results suggest that DEHP exposed alone or combined with DBP caused a variety of metabolic disorders, and the type of combination effects varied among metabolic pathways.

Altered gut microbiota community structure and correlated immune system changes in dibutyl phthalate exposed mice

Di-n-butyl phthalate (DBP) is a ubiquitous environmental contaminant linked with various adverse health effects, including immune system dysfunction. Gut microbial dysbiosis can contribute to a wide range of pathogenesis, particularly immune disease. Here, we investigated the impact of DBP on the gut microbiome and examined correlations with immune system changes after five weeks oral exposure (10 or 100 mg/kg/day) in adult male mice. The fecal microbiome composition was characterized using 16S rRNA sequencing. DBP-treated mice displayed a significantly distinct microbial community composition, indicated by Bray-Curtis distance. Numerous amplicon sequence variants (ASVs) at the genus level were altered. Compared to the vehicle control group, the 10 mg/kg/day DBP group had 63 more abundant and 65 less abundant ASVs, while 60 ASVs were increased and 76 ASVs were decreased in the 100 mg/kg/day DBP group. Both DBP treatment groups showed higher abundances of ASVs assigned to Desulfovibrio (Proteobacteria phylum) and Enterorhabdus genera, while ASVs belonging to Parabacteroides, Lachnospiraceae UCG-006 and Lachnoclostridium were less common compared to the control group. Interestingly, an ASV belonging to Rumniniclostridium 6, which was less abundant in DBP-treated mice, demonstrated a negative correlation with the increased number of non-classical monocytes observed in the blood of DBP-treated animals. In addition, an ASV from Lachnospiraceae UCG-001, which was more abundant in the DBP-treated animals, showed a positive correlation with the non-classical monocyte increase. This study shows that DBP exposure greatly modifies the gut bacterial microbiome and indicates a potential contribution of microbial dysbiosis to DBP-induced immune system impairment, illustrating the importance of investigating how interactions between exposome components can affect health.

Ferroptosis participates in dibutyl phthalate-aggravated allergic asthma in ovalbumin-sensitized mice

Dibutyl phthalate (DBP), used as a plasticizer, is of wide concern as an environmental pollutant since it has certain immunotoxicity. Although there is growing evidence supporting a link between DBP exposure and allergic airway inflammation, there is less information concerned with whether the ferroptosis pathway is involved in DBP-aggravated allergic asthma in ovalbumin (OVA)-sensitized mice. This study aimed to investigate the role and underlying mechanisms of ferroptosis in DBP-exposed allergic asthmatic mice. Balb/c mice were orally exposed to 40 mg/kg^-1 DBP for 28 days, followed by sensitization with OVA and seven consecutive challenges with nebulized OVA. We analyzed airway hyperresponsiveness (AHR), immunoglobulins, inflammation and pulmonary histopathology, to investigate whether DBP exacerbates allergic asthma in OVA-induced mice. We also measured the biomarkers of ferroptosis (Fe²⁺, GPX4, PTGS2), proteins related to the ferroptosis pathway (VEGF, IL-33, HMGB1, SLC7A11, ALOX15, PEBP1), and indices of lipid peroxidation (ROS, Lipid ROS, GSH, MDA, 4-HNE), to explore the role of ferroptosis in DBP+OVA mice. Finally, we used ferrostatin-1 (Fer-1) as an antagonist against the harmful effects of DBP. The results showed that, DBP+OVA mice had a significant increase in AHR, airway wall remodeling and airway inflammation. Further, we showed that DBP aggravated allergic asthma via ferroptosis and lipid peroxidation, and that Fer-1 inhibited ferroptosis and alleviated the pulmonary toxicity of DBP. These results suggest that ferroptosis participates in the exacerbation of allergic asthma resulting from oral exposure to DBP, highlighting a novel pathway for the connection between DBP and allergic asthma.

Disrupted microbiota-barrier-immune interaction in phthalates-mediated barrier defect in the duodenum

As one of the most used phthalates, Di (2-ethylhexyl) phthalate (DEHP) is a widespread environmental contaminant. Extremely persistent plastic can enter the food chain of animals through the aquatic environment, affect metabolic pathways and cause damage to the digestive system. But the molecular mechanism of its toxic effects on the duodenum in birds has not been elucidated. To investigate the toxicity of phthalates in the duodenum, quails were gavaged with 250, 500, and 750 mg/kg doses of DEHP for 45 days, and water and oil control groups were retained. This study revealed that subchronic exposure to DEHP could lead to duodenal barrier defect in quail. The damage to duodenum was reflected in a reduction in V/C and tight junction proteins. Moreover, DEHP also led to a breakdown of antimicrobial defenses through the flora derangement, which acted as a biological barrier. The massive presence of Lipopolysaccharide (LPS) led to the activation of TLR4 receptors. In addition, DEHP activated oxidative stress, which synergized the inflammatory response induced by the TLR4-NFκB pathway, and further promoted duodenum damage. This study provides a base for the further effect of phthalates on the microbiota-barrier-immune interaction.

The influence of perinatal maternal exposure to dibutyl phthalate on glucolipid metabolism in adult female offspring

BACKGROUND

Maternal exposure to dibutyl phthalate (DBP) may result in obesity in female offspring. However, the underlying mechanisms remain elusive.

MATERIALS AND METHODS

Sprague-Dawley rats were intraperitoneally injected with different doses of DBP and corn oil from gestational day 7 until the end of lactation. The weights, visceral fat percentage, serum lipid, insulin and glucose, protein levels of PI3K signal pathway in muscle were detected in F1 female offspring.

RESULTS

Although the birth weight of F1 female offspring was not different among groups, the weights were heavier in DBP groups from postnatal day 7 to adult (P < 0.001). The visceral adipose percentage in adult female offspring was increased by perinatal exposure to DBP (P < 0.001). Decreased serum level of triglyceride (P = 0.001) in F1 female offspring was found in DBP group as compared to control, especially in medium and high DBP. However, none difference was found for fasting glucose, prolactin, HOMA-IR, fasting insulin, total cholesterol, adiponectin. Different protein levels of GPR30 were observed in muscle of female offspring among four groups (P = 0.016). The protein level of AKT seemed higher in DBP group but without statistical significance (P = 0.05). None difference was observed for the protein levels of PI3K, p-AKT, pAKT/AKT, PTEN, GLUT4, InsR, IRS.

CONCLUSION

Maternal perinatal exposure to DBP might induce obesity and accumulation of visceral adipose tissue for the adult female offspring. Serum glucolipid and local signal transduction of PTEN/PI3K/AKT pathway in muscle were not adversely affected by perinatal exposure to DBP for adult female offspring.

Protective effect of quercetin against phthalates induced hepatotoxicity in rats

Humans are increasingly exposed to ubiquitous phthalates (PEs), e.g. butyl benzyl phthalate (BBP), dibutyl phthalate (DBP), and di(2-ethylhexyl) phthalate (DEHP), which are widely used plasticizers in polymer products. This study was aimed to investigate the effect of phytochemical quercetin (Que) on hepatotoxicity caused by the mixture of the 3 commonly used PEs (MPEs), and further to explore the underlying mechanism. Forty male Sprague-Dawley rats were randomly divided into control group, MPEs group, and MPEs combined Que at Low-, Median-, and High-dose groups; rats in MPEs group were orally administered with 900 mg/kg/d MPEs, whereas rats in MPEs combined Que groups were simultaneously treated with 900 mg/kg/d MPEs and respectively 10, 30, and 90 mg/kg/d Que. The intervention last 30 days. Compared with control group, serum ALT, AST, LDH and AKP, and hepatic MDA, SOD, CAT and GPx were significantly increased, whereas, serum albumin and total protein were significantly decreased in MPEs group (P < 0.05); hepatic histopathological observation showed numerous inflammatory cells infiltration, hepatocyte ballooning degeneration, and numerous residual erythrocytes in the central vein in MPEs group. Western-blot analysis showed that hepatic Keap1 was downregulated, whereas Nrf2 and HO-1 were upregulated in MPEs group (P < 0.05). However, the alterations of these parameters were alleviated in MPEs combined Que at Median- and High-dose groups. The results indicated that MPEs-induced hepatic oxidative stress, and caused hepatic injuries; whereas, Que inhibited MPEs' hepatotoxicity, which might relate to Que's ability of quenching free radicals directly, and restored the regulation of Nrf2 signaling pathway.

Sporoderm-broken spores of Ganoderma lucidum alleviates liver injury induced by DBP and BaP co-exposure in rat

Dibutyl phthalate (DBP) and Benzo(a)pyrene (BaP) are ubiquitous contaminants in environment and foodstuffs, which increase the chance of their combined exposure to humans in daily life. However, the combined effects of DBP and BaP on liver and the underlying mechanisms are still unclear. In this study, we explored the combined effects of DBP and BaP on liver and the potential mechanisms in a rat model. We found that DBP and BaP co-exposure activated the MyD88/NF-κB pathway through increasing TLR4 acetylation (TLR4ac) level, leading to the imbalance of pro-inflammatory factors (CXCL-13, IL-6 and TNF-α) and anti-inflammatory factors (IL-10), ultimately resulting in liver tissue damage and functional changes. Sporoderm-broken spores of Ganoderma lucidum (SSGL) had strong alleviating effects on liver injury induced by DBP and BaP co-exposure. Our study found that SSGL suppressed TLR4ac-regulated MyD88/NF-κB signaling to reduce the release of pro-inflammatory factors, and promote the secretion of IL-10, thus alleviating liver injury caused by DBP and BaP co-exposure. In conclusion, SSGL contributed to liver protection against DBP and BaP-induced liver injury in rats via suppressing the TLR4ac-regulated MyD88/NF-κB signaling.

Impact of Environmental Pollutants on Gut Microbiome and Mental Health via the Gut–Brain Axis

Over the last few years, the microbiome has emerged as a high-priority research area to discover missing links between brain health and gut dysbiosis. Emerging evidence suggests that the commensal gut microbiome is an important regulator of the gut–brain axis and plays a critical role in brain physiology. Engaging microbiome-generated metabolites such as short-chain fatty acids, the immune system, the enteric nervous system, the endocrine system (including the HPA axis), tryptophan metabolism or the vagus nerve plays a crucial role in communication between the gut microbes and the brain. Humans are exposed to a wide range of pollutants in everyday life that impact our intestinal microbiota and manipulate the bidirectional communication between the gut and the brain, resulting in predisposition to psychiatric or neurological disorders. However, the interaction between xenobiotics, microbiota and neurotoxicity has yet to be completely investigated. Although research into the precise processes of the microbiota–gut–brain axis is growing rapidly, comprehending the implications of environmental contaminants remains challenging. In these milieus, we herein discuss how various environmental pollutants such as phthalates, heavy metals, Bisphenol A and particulate matter may alter the intricate microbiota–gut–brain axis thereby impacting our neurological and overall mental health.

Long-term co-exposure DBP and BaP causes imbalance in liver macrophages polarization via activation of Notch signaling regulated by miR-34a-5p in rats

Humans are often exposed to complex mixtures of environmental pollutants over long periods of time. It is reported that Dibutyl phthalate (DBP) and benzo[a]pyrene (BaP) are typical environmental pollutants, which are associated with liver injury. Nevertheless, little is known about the effects of DBP and BaP combined exposure on liver. In the current study, rats were exposed to DBP alone (50, or 250 mg/kg), BaP alone (1, or 5 mg/kg), or DBP and BaP (50 + 1, or 250 + 5 mg/kg) for ninety days. More serious liver damage, including abnormal liver function, infiltration of inflammatory cells and disturbed secretion of inflammatory factors, were observed in long-term co-exposure to DBP and BaP group relative to those in single exposure group. Our data showed that long-term co-exposure to DBP and BaP induces macrophages to polarize toward M1 and inhibits polarization of M2 macrophages. Long-term co-exposure to DBP and BaP downregulated miR-34a-5p level and upregulated Notch signaling. These results indicated that imbalance in macrophages M1/M2 polarization mediated by activation of Notch signaling due to reduced miR-34a-5p level may contribute to additive effects on disorder of inflammatory factors secretion and subsequent liver injury following long-term DBP and BaP co-exposure.

Chronic systemic low-grade inflammation and modern lifestyle: the dark role of gut microbiota on related diseases with a focus on pandemic COVID-19

Inflammation is a physiological, beneficial and auto-limiting response of the host to alarming stimuli. Conversely, a chronic systemic low-grade inflammation (CSLGI), known as a long-time persisting condition, causes organs and host tissues' damage, representing a major risk for chronic diseases. Currently, a worldwide a high incidence of inflammatory chronic diseases is observed, often linked to the lifestyle-related changes occurred in the last decade's society. The mains lifestyle-related factors are a proinflammatory diet, psychological stress, tobacco smoking, alcohol abuse, physical inactivity, and finally indoor living and working with its related consequences such as indoor pollution, artificial light exposure and low vitamin D production. Recent scientific evidences found that gut microbiota (GM) has a main role in shaping the host's health, particularly as CSLGI mediator. As a matter of facts, based on the last discoveries regarding the remarkable GM activity, in this manuscript we focused on the elements of actual lifestyle that influence the composition and function of intestinal microbial community, in order to elicit the CSLGI and its correlated pathologies. In this scenario, we provide a broad review of the interplay between modern lifestyle, GM and CSLGI with a special focus on the COVID symptoms and emerging long-COVID syndrome.

Procyanidins from Hawthorn (Crataegus Pinnatifida) Alleviates Lipid Metabolism Disorder via Inhibiting Insulin Resistance and Oxidative Stress, Normalizing Gut Microbiota Structure and Intestinal Barrier, Further Suppressing Hepatic Inflammation and Lipid Accumulation

Recently, lipid metabolism disorder (LMD) has been regarded as a risky factor leading to multiple diseases and affecting human health. Procyanidins have been reported to be the potential therapy for...

FLEXiGUT: Rationale for exposomics associations with chronic low-grade gut inflammation

FLEXiGUT is the first large-scale exposomics study focused on chronic low-grade inflammation. It aims to characterize human life course environmental exposure to assess and validate its impact on gut inflammation and related biological processes and diseases. The cumulative influences of environmental and food contaminants throughout the lifespan on certain biological responses related to chronic gut inflammation will be investigated in two Flemish prospective cohorts, namely the "ENVIRONAGE birth cohort", which provides follow-up from gestation to early childhood, and the "Flemish Gut Flora Project longitudinal cohort", a cohort of adults. The exposome will be characterised through biomonitoring of legacy and emerging contaminants, mycotoxins and markers of air pollution, by analysing the available metadata on nutrition, location and activity, and by applying state-of-the-art -omics techniques, including metagenomics, metabolomics and DNA adductomics, as well as the assessment of telomere length and measurement of inflammatory markers, to encompass both exposure and effect. Associations between exposures and health outcomes will be uncovered using an integrated -omics data analysis framework comprising data exploration, pre-processing, dimensionality reduction and data mining, combined with machine learning-based pathway analysis approaches. This is expected to lead to a more profound insight in mechanisms underlying disease progression (e.g. metabolic disorders, food allergies, gastrointestinal cancers) and/or accelerated biological ageing.

miR-122-5p regulates hepatocytes damage caused by BaP and DBP co-exposure through SOCS1/STAT3 signaling in vitro

BaP and DBP are ubiquitously and contemporaneously present in the environment. However, Current studies largely concentrate on the effects of a single pollutant (BaP or DBP). The liver is vital for biogenic activities. The effects of BaP and DBP co-exposure on liver remain unclear. Thus, we treated human normal liver cell (L02 cell) with BaP or/and DBP. We found that compared to individual exposure, co-exposure to BaP and DBP induced further increased levels of AST and ALT. BaP and DBP co-exposure caused further increased levels of IL-2, IL-6, and TNF-α, decreased IL-10 level, and a higher percentage of apoptotic cells and S-phase arrest cells. BaP and DBP co-exposure worsen the decrease of miR-122-5p level and chaos of SOCS1/STAT3 signaling. Dual-luciferase reporter gene assays showed that SOCS1 was a validated target of miR-122-5p. miR-122-5p overexpression alleviated the increased SOCS1 expression, decreased phospho-STAT3 expression, decreased IL-10 level, increased TNF-α levels, increased percentage of apoptosis and S-phase arrest, and cytotoxicity induced by BaP and DBP co-exposure in hepatocytes. These results suggested that miR-122-5p negatively regulated the synergistic effects on apoptosis and disorder of inflammatory factor secretion involved in hepatocyte injury caused by BaP and DBP co-exposure through targeting SOCS1/STAT3 signaling.

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

Arsenic is an important hazardous metalloid commonly found in polluted soil, rivers and groundwater. However, few studies exist regarding the effect of arsenic trioxide (ATO) on the gut-liver axis and consequent hepatotoxicity in waterfowl. Here, we investigated the influence of ATO on duck intestines and livers, and explored the role of the gut-liver axis in ATO-induced hepatotoxicity and intestinal toxicity. Our results demonstrated that ATO-exposure induced intestinal damage, liver inflammatory cell infiltration and vesicle steatosis. Additionally, the intestinal microbiota community in ATO-exposed ducks displayed significantly decreased α-diversity and an altered bacterial composition. Moreover, ATO-exposure markedly reduced the expression of intestinal barrier-related proteins (Claudin-1, MUC2, ZO-1 and Occludin), resulting in increased intestinal permeability and elevated lipopolysaccharide levels. Simultaneously, ATO-exposure also upregulated pyroptosis-related index levels in the liver and jejunum, and increased pro-inflammatory cytokine production (IFN-γ, TNF-α, IL-18, and IL-1β). Our further mechanistic studies showed that ATO-induced liver and jejunum inflammation were provoked by the activation of the LPS/TLR4/NF-κB signaling pathway and NLRP3 inflammasome. In summary, these results manifested that ATO exposure can cause liver and jejunal inflammation and pyroptosis, and the indirect gut-liver axis pathway may play an essential role in the potential mechanism of ATO-induced hepatotoxicity.

Probiotic reduced the impact of phthalates and bisphenol A mixture on type 2 diabetes mellitus development: Merging bioinformatics with in vivo analysis

Linkage between bis(2-ethylhexyl) phthalate (DEHP), dibutyl phthalate (DBP), and bisphenol A (BPA) co-exposure and type 2 diabetes mellitus (T2DM), as well as ability of multi-strained probiotic to reduce DEHP, DBP and BPA mixture-induced oxidative damage in rat pancreas were investigated. The Comparative Toxicogenomics Database, Cytoscape software and ToppGene Suite were used for data-mining. Animals were sorted into seven groups (n = 6): (1) Control group: corn oil, (2) P: probiotic: Saccharomyces boulardii + Lactobacillus rhamnosus + Lactobacillus plantarum LP 6595 + Lactobacillus plantarum HEAL9; (3) DEHP: 50 mg/kg b.w./day, (4) DBP: 50 mg/kg b.w./day, (5) BPA: 25 mg/kg b.w./day, and (6) MIX: 50 mg/kg b.w./day DEHP + 50 mg/kg b.w/day DBP + 25 mg/kg b.w./day BPA; (7) MIX + P. Rats were sacrificed after 28 days of oral exposure. In silico investigation highlighted 44 DEHP, DBP and BPA mutual genes linked to the T2DM, while apoptosis and oxidative stress were highlighted as the main mechanisms of DEHP, DBP and BPA mixture-linked T2DM. In vivo experiment confirmed the presence of significant changes in redox status parameters (TOS, SOD and SH groups) only in the MIX group, indicating possible additive effects, while probiotic ameliorated mixture-induced redox status changes in rat pancreatic tissue.