DEHP induce cholesterol imbalance via disturbing bile acid metabolism by altering the composition of gut microbiota in rats

A systematic review of global distribution, sources and exposure risk of phthalate esters (PAEs) in indoor dust

Phthalate esters (PAEs) are a class of plasticizers that are readily released from plastic products, posing a potential exposure risk to human body. At present, much attention is paid on PAE concentrations in indoor dust with the understanding of PAEs toxicity. This study collected 8187 data on 10 PAEs concentrations in indoor dusts from 26 countries and comprehensively reviewed the worldwide distribution, influencing factors, and health risks of PAEs. Di-(2-ethylhexyl) phthalate (DEHP) is the predominant PAE with a median concentration of 316 μg·g-1 in indoor dust. Polyvinyl chloride wallpaper and flooring and personal care products are the main sources of PAEs indoor dust. The dust concentrations of DEHP show a downward trend over the past two decades, while high dust concentrations of DiNP are found from 2011 to 2016. The median dust contents of 8 PAEs in public places are higher than those in households. Moreover, the concentrations of 9 PAEs in indoor dusts from high-income countries are higher than those from upper-middle-income countries. DEHP in 69.8% and 77.8% of the dust samples may pose a potential carcinogenic risk for adults and children, respectively. Besides, DEHP in 16.9% of the dust samples may pose a non-carcinogenic risk to children. Nevertheless, a negligible risk was found for other PAEs in indoor dust worldwide. This review contributes to an in-depth understanding of the global distribution, sources and health risks of PAEs in indoor dust.

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.

Disrupting the gut microbiota/metabolites axis by Di-(2-ethylhexyl) phthalate drives intestinal inflammation via AhR/NF-κB pathway in mice

Di-(2-ethylhexyl) phthalate (DEHP) is a widely used plasticizer known for its environmental endocrine-disrupting properties, posing potential risks to various organs. However, the precise impact of DEHP on intestinal health and its contribution to the initiation of intestinal inflammation remains elucidated. This study aims to investigate the underlying mechanisms of DEHP-induced intestinal inflammation in mice, specifically focusing on the complex interplay between the gut microbiota-metabolite axis and associated pathophysiological alterations. Our findings showed that DEHP-induced damage of multiple organs systemically, as indicated by abnormal liver and kidney biochemical markers, along with a disrupted ileum morphology. Additionally, DEHP exposure disrupted gut barrier function, causing intestinal inflammation characterized by bacterial translocation and alterations in defense and inflammation-related gene expressions. Moreover, 16S rRNA analysis suggested that DEHP-induced gut microbial remodeling is characterized by an upregulation of detrimental bacteria (Erysipelotrichaceae) and a downregulation of beneficial bacteria (Muribaculaceae, Ruminococcaceae, and Lachnospiraceae). Metabolomics analysis revealed DEHP perturbed gut metabolic homeostasis, particularly affecting the degradation of aromatic compounds, which generated an aberrant activation of the AhR and NF-κB, subsequently causing intestinal inflammation. Consequently, our results elucidate the mechanistic link between disrupted gut microbiota and metabolome and the initiation of DEHP-induced intestinal inflammation, mediated through the AhR/NF-κB signaling pathway.

Chronic triclosan exposure induce impaired glucose tolerance by altering the gut microbiota

Triclosan (TCS) is an antimicrobial compound incorporated into more than 2000 consumer products. This compound is frequently detected in the human body and causes ubiquitous contamination in the environment, thereby raising concerns about its impact on human health and environmental pollution. Here, we demonstrated that 20 weeks' exposure of TCS drove the development of glucose intolerance by inducing compositional and functional alterations in intestinal microbiota in rats. Fecal-transplantation experiments corroborated the involvement of gut microbiota in TCS-induced glucose-tolerance impairment. 16S rRNA gene-sequencing analysis of cecal contents showed that TCS disrupted the gut microbiota composition in rats and increased the ratio of Firmicutes to Bacteroidetes. Cecal metabolomic analyses detected that TCS altered host metabolic pathways that are linked to host glucose and amino acid metabolism, particularly branched-chain amino acid (BCAA) biosynthesis. BCAA measurement confirmed the increase in serum BCAAs in rats exposed to TCS. Western blot and immunostaining results further confirmed that elevated BCAAs stimulated mTOR, a nutrient-sensing complex, and following IRS-1 serine phosphorylation, resulted in insulin resistance and glucose intolerance. These results suggested that TCS may induce glucose metabolism imbalance by regulating BCAA concentration by remodeling the gut microbiota.

Oyster Peptide-Zinc Complex Ameliorates Di-(2-ethylhexyl) Phthalate-Induced Testis Injury in Male Mice and Improving Gut Microbiota

Di-(2-ethylhexyl) phthalate (DEHP) is a widely used plasticizer, which can cause damage to male reproductive organs, especially the atrophy of the testis. Meanwhile, DEHP can also lead to a decrease in testicular zinc content, but the role of zinc remains unclear. This study aims to prepare oyster peptide-zinc complex (OPZC) to alleviate DEHP-induced reproductive damage in mice. OPZC was successfully obtained through electron microscopy, X-ray diffraction, and thermogravimetric analysis, with stable structure and high water-solubility. Low dose oyster peptide-zinc complex (OPZCL) significantly reduced the reproductive damage caused by DEHP in mice. Further research had shown that OPZCL restored the content of serum hormones and the activity of oxidative stress kinases to normal, while also normalizing testicular zinc and selenium levels. In addition, it also recovered the disorder of gut microbiota, reduced the proportion of Bacteroides, increased the abundance of Ligilactobacillus, and restored the proportion of Acidobacteriota, Chloroflexi, and Proteobacteria. Therefore, OPZCL can relieve the reproductive damage caused by DEHP in mice by restoring testicular zinc homeostasis and the composition of intestinal microbiota, indicating that OPZCL has a potential protective effect on male reproductive health.

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.

Bu-Shen-Tian-Jing formulas alleviate the mitochondrial damage induced by oxidative stress in ovarian granulosa cells exposed to DEHP through the HDAC3-HSP90AA pathway

CONTEXT

di-(2-Ethylhexyl) phthalate (DEHP) has potential reproductive toxicity. Bu-Shen-Tian-Jing formulations (BSTJFs) are beneficial for female reproductive capacity. However, BSTJF2 has much lower cytotoxicity than BSTJF1.

OBJECTIVE

To investigate the effects of BSTJFs on ovarian granulosa cells exposed to DEHP and determine the potential molecular mechanisms.

METHODS AND MATERIALS

Human granulosa-like tumor cell line (KGN) cells were divided into control, DEHP, BSTJF1 and BSTJF2 groups. The DEHP group were given 1 μM DEHP for 24 h. They were then given BSTJF1 at 200 μg/mL or BSTJF2 at 100 μg/mL for 24 h. The control group was treated with the same concentration of DMSO (0.1%). Oxidative stress and mitochondrial function were measured. The mRNA and protein expression levels of HDAC3 and HSP90AA were determined. Integrative network pharmacology analysis of BSTJF2 was also performed.

RESULTS

DEHP (1 μM) significantly suppressed the proliferation of KGN cells by 17%, significantly increased ROS levels by 28% and MDA levels by 47%, significantly decreased MMP levels by 22% and mtDNA copy by 30%. DEHP significantly increased protein expression of HDAC3 by 21%and HSP90AA by 64%. All these changes were significantly reversed by BSTJFs. Integrative network pharmacology analysis revealed HSP90AA was a key target (degree = 8). Both RGFP966 and BSTJF2 significantly reversed the increased expression of HDAC3 and HSP90AA, attenuated oxidative stress, and mitochondrial damage which were induced by DEHP.

CONCLUSION

BSTJFs might have therapeutic potential on oxidative stress and mitochondrial damage through the HDAC3/HSP90AA pathway which encourages further clinical trials.

Obeticholic acid alleviates intrauterine growth restriction induced by di-ethyl-hexyl phthalate in pregnant female mice by improving bile acid disorder

Di-(2-ethylhexyl)-phthalate (DEHP) is a ubiquitous environmental pollutant and is widely used in industrial plastics. Intrahepatic cholestasis of pregnancy (ICP), distinguished by maternal pruritus and elevated serum bile acid levels, is linked to unfavorable pregnancy consequences. Few studies have investigated the potential effect of gestational DEHP exposure on the cholestasis in pregnant female mice, and the underlying mechanisms remain unclear. In the present study, a mouse model of cholestasis during pregnancy was established by DEHP exposure. We found that DEHP induces elevated bile acid levels by affecting bile acid synthesis and transporter receptor expression in the maternal liver and placenta of pregnant female mice, ultimately leading to intrauterine growth restriction (IUGR). In addition, DEHP changed the bile acid composition of maternal serum and liver as well as placenta and amniotic fluid in pregnant female mice; Importantly, we found that DEHP down-regulates the expression of farnesoid X receptor (FXR), which is considered to be a bile acid receptor. FXR agonist obeticholic acid (OCA) effectively alleviated the adverse effects of DEHP on pregnant female mice. While, OCA itself had no adverse effects on normal pregnant female mice. In summary, DEHP could induces bile acid disorder and IUGR in pregnant female mice by affect FXR, which was reversed by OCA.

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.

Untargeted Metabolomics Analysis Reveals Toxicity Based on the Sex and Sexual Maturity of Single Low-Dose DEHP Exposure

Di-(2-Ethylhexyl) phthalate (DEHP) is a prevalent environmental endocrine disruptor that affects homeostasis, reproduction, and developmental processes. The effects of DEHP have been shown to differ based on sex and sexual maturity. This study examines the metabolic profiles of mature adult rats from both sexes, aged 10 weeks, and adolescent female rats, aged 6 weeks, following a single 5 mg/kg of body weight DEHP oral administration. An untargeted metabolomic analysis was conducted on urine samples collected at multiple times to discern potential sex- and maturity-specific DEHP toxicities. Various multivariate statistical analyses were employed to identify the relevant metabolites. The findings revealed disruptions to the steroid hormone and primary bile acid biosynthesis. Notably, DEHP exposure increased hyocholic, muricholic, and ketodeoxycholic acids in male rats. Moreover, DEHP exposure was linked to heart, liver, and kidney damage, as indicated by increased plasma GOT1 levels when compared to the levels before DEHP exposure. This study provides detailed insights into the unique mechanisms triggered by DEHP exposure concerning sex and sexual maturity, emphasizing significant distinctions in lipid metabolic profiles across the different groups. This study results deepens our understanding of the health risks linked to DEHP, informing future risk assessments and policy decisions.

DEHP exposure elevated cardiovascular risk in obese mice by disturbing the arachidonic acid metabolism of gut microbiota

Phthalate esters (PAEs) are one of the significant classes of emerging contaminants that are increasingly detected in environmental and human samples. Nevertheless, the current toxicity studies rarely report how PAEs affect the cardiovascular system, especially in obese individuals. In this study, diet-induced obese mice and corresponding normal mice were exposed to di(2-ethylhexyl) phthalate (DEHP) by oral gavage at environmentally relevant concentrations and key characteristics of cardiovascular risk were examined. The 16S rRNA and high-resolution mass spectrometry were used to investigate the alterations in the gut microbial profile and metabolic homeostasis. The results indicated that the cardiovascular system of fat individuals was more susceptible to DEHP exposure than mice in the lean group. 16S rRNA-based profiling and correlation analysis collectively suggested DEHP-induced gut microbial remodeling in fed a high-fat diet mice, represented by the abundance of the genus Faecalibaculum. Using metagenomic approaches, Faecalibaculum rodentium was identified as the top-ranked candidate bacterium. Additionally, metabolomics data revealed that DEHP exposure altered the gut metabolic homeostasis of arachidonic acid (AA), which is associated with adverse cardiovascular events. Finally, cultures of Faecalibaculum rodentium were treated with AA in vitro to verify the role of Faecalibaculum rodentium in altering AA metabolism. Our findings provide novel insights into DEHP exposure induced cardiovascular damage in obese individuals and suggest that AA could be used as a potential modulator of gut microbiota to prevent related diseases.

Colonic mechanism of serum NAD+ depletion induced by DEHP during pregnancy

Di (2-ethylhexyl) phthalate (DEHP) is a widely used plasticizer in polyvinyl chloride products such as feed piping, packing bag, and medical consumable. Our previous studies have demonstrated that DEHP exposure reduced the concentration of nicotinamide adenine dinucleotide (NAD⁺) in pregnant mice serum, which cuts off the source of NAD⁺ to placenta and results fetal growth restriction. However, the mechanism of serum NAD⁺ depletion by DEHP remains elusive. This study investigated the intestinal mechanism of NAD⁺ shortage-induced by DEHP in pregnant mice. The transcriptome results implicated that the mRNA level of oxidative response genes Cyp1a1, Gsto2, Trpv1 and Trpv3 were upregulated in colon. These changes induced intestinal inflammation. Transmission Electron Microscopy results displayed that DEHP destroyed the tight junctions and cell polarity of colonic epithelial cells. These dysfunctions diminished the expression of NAD⁺ precursor transporters SLC12A8, SLC5A8, SLC7A5, and the NAD⁺ biosynthetic key enzymes NAMPT, NMNAT1-3, and TDO2 in colonic epithelial cells. Analysis of the gut microbiota showed that DEHP led to the dysbiosis of gut microbiota, reducing the relative abundance of Prevotella copri which possesses the VB3 biosynthetic pathway. Therefore, maternal DEHP exposure during pregnancy decreased the transportation of NAD⁺ precursors from enteric cavity to colonic epithelial cells, and inhibited the synthesis of NAD⁺ in colonic epithelial cells. Meanwhile, DEHP reduced the NAD⁺ precursors provided by gut microbiota. Eventually, serum NAD⁺ content was lowered. Taken together, our findings provide a new insight for understanding the intestinal mechanisms by which DEHP affects serum NAD⁺ levels.

Dose-dependent toxic effects of di-(2-ethylhexyl) phthalate in male rats: Focus on behavioral alterations and inducing TLR4/NF-κB signaling pathway

Di -(2-ethylhexyl) phthalate (DEHP) is a widely used phthalate that possesses a public health concern. Different concentrations of DEHP, including 50, 300, and 750 mg/kg, were administrated orally for 28 days in male rats. Body weight and vital organs weight were measured as well as anxiety-like behavior, short and long-term memory were investigated. Brain inflammatory cytokines, including IL-1β, TLR4, NF-κB, TNF-α, and IL1-6, were assessed. Brain caspase-3, neuropeptide-Y (NPY), and brain histopathology were also evaluated. DEHP triggers the release of pro-inflammatory cytokines via inducing the nuclear translocation of the signaling pathway; TLR 4/ NF-κB leads to cognitive impairment and neurodegeneration, which is confirmed by the impaired brain architecture. Also, DEHP upgrades the expression levels of brain caspase-3 and NPY. In conclusion, exposure to high doses of DEHP persuades great toxicity visualized by behavioral, biochemical, and histological impairments when compared to the low dose.

Subchronic exposure to environmentally relevant concentrations of di-(2-ethylhexyl) phthalate differentially affects the colon and ileum in adult female mice

Di(2-ethylhexyl) phthalate (DEHP) is a large-molecular-weight phthalate added to plastics to impart versatile properties. DEHP can be found in medical equipment and devices, food containers, building materials, and children's toys. Although DEHP exposure occurs most commonly by ingesting contaminated foods in the majority of the population, its effects on the gastrointestinal tract have not been well studied. Therefore, we analyzed the effects of subchronic exposure to DEHP on the ileum and colon morphology, gene expression, and immune microenvironment. Adult C57BL/6 female mice were orally dosed with corn oil (control, n = 7) or DEHP (0.02, 0.2, or 30 mg/kg, n = 7/treatment dose) for 30-34 days. Mice were euthanized during diestrus, and colon and ileum tissues were collected for RT-qPCR and immunohistochemistry. Subchronic DEHP exposure in the ileum altered the expression of several immune-mediating factors (Muc1, Lyz1, Cldn1) and cell viability factors (Bcl2 and Aifm1). Similarly, DEHP exposure in the colon impacted the gene expression of factors involved in mediating immune responses (Muc3a, Zo2, Ocln, Il6, and Il17a); and also altered the expression of cell viability factors (Ki67, Bcl2, Cdk4, and Aifm1) as well as a specialized epithelial cell marker (Vil1). Immunohistochemical analysis of the ileum showed DEHP increased expression of VIL1, CLDN1, and TNF and decreased number of T-cells in the villi. Histological analysis of the colon showed DEHP altered morphology and reduced cell proliferation. Moreover, in the colon, DEHP increased the expression of MUC2, MUC1, VIL1, CLDN1, and TNF. DEHP also increased the number of T-cells and Type 2 immune cells in the colon. These data suggest that subchronic DEHP exposure differentially affects the ileum and colon and alters colonic morphology and the intestinal immune microenvironment. These results have important implications for understanding the effects of DEHP on the gastrointestinal system.

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.

Vitamin C mitigates hematological and biochemical alterations caused by di(2-ethylhexyl) phthalate toxicity in female albino mice, Mus musculus

Di(2-ethylhexyl) phthalate (DEHP) is ubiquitous environmental contaminant and identified as endocrine-disrupting chemical (EDC), present in plastics as plasticizer. Due to its versatile use, human exposure level reaches to danger limit. The main focus of our study is to see the effect of vitamin C on hematological and biochemical alterations caused by Di(2-ethylhexyl) Phthalate toxicity in female albino mice, Mus musculus. It is found to cause defects of the liver, kidney, and lungs. Its anti-androgenic nature brings the main focus on its toxicity associated with reproductive and endocrine system. In this experimental study, 18 young female Swiss albino mice, Mus musculus, were used and divided into 3 groups of 6 animals each as control (corn oil vehicle), DEHP group (100 mg/kg body weight dissolved in corn oil), and DEHP + vitamin-C group (100 mg/kg body weight each, dissolved in corn oil and double distilled water, respectively) for 90 days. In this research, serum metabolites were evaluated to study the effect of DEHP on glucose, total protein, and lipid profile along with some hematological, enzymological, and oxidative stress parameters. Simultaneously, we compared the effectiveness of vitamin-C against DEHP toxicity to mitigate the serum homeostasis disturbance. In present study, we observed, in DEHP-treated animals, glucose, triglycerides, very-low-density lipoprotein (VLDL), total protein, alkaline phosphatase (ALP), acid phosphatase (ACP), and alanine aminotransferase (ALT) levels increased remarkably, whereas total cholesterol, high-density lipoproteins (HDL), aspartate aminotransferase (AST), total RBC count, total WBC count, and hemoglobin (Hb) level significantly decreased as compared to control group. In addition, we noticed there was a decrease in superoxide dismutase (SOD) and increase in levels of lipid peroxidation (MDA) and interleukin-6 (IL-6) in DEHP treatment group as compared to control group. The results indicated vitamin C had a better improving effect against DEHP toxicity on balancing metabolic abnormalities and inflammation-related comorbidities.

Di(2-ethylhexyl) phthalate disturbs cholesterol metabolism through oxidative stress in rat liver

Di(2-ethylhexyl) phthalate (DEHP) is widely used and has been implicated in hepatotoxicity, although the mechanism is unclear. Here, we investigated the effect of DEHP on hepatic cholesterol metabolism in SD rats exposed to 0 and 300 mg/kg/day DEHP for 12 weeks. An RNA-Seq analysis was performed to describe the hepatic responses to long-term DEHP exposure in combination with serological and oxidative stress parameter measurements. DEHP increased the serum levels of total cholesterol (TC), high-density lipoprotein (HDL), and alanine transaminase (ALT). Moreover, DEHP increased the content of malondialdehyde (MDA) and decreased antioxidant enzyme activities in the liver. Transcriptomic results revealed that DEHP dramatically changed the cholesterol metabolism pathway and oxidation-reduction process and depressed gene expression involved in cholesterol efflux and monooxygenase activity. Total antioxidant capacity (T-AOC) positively correlated with Abcg5 and Abcg8. Overall, this study showed the mechanisms underlying hepatotoxicity caused by DEHP, providing new insights into understanding DEHP poisoning.

FXR Signaling-Mediated Bile Acid Metabolism Is Critical for Alleviation of Cholesterol Gallstones by Lactobacillus Strains

Cholesterol gallstone (CGS) disease is characterized by an imbalance in bile acid (BA) metabolism and is closely associated with gut microbiota disorders. However, the role and mechanism by which probiotics targeting the gut microbiota attenuate cholesterol gallstones are still unknown. In this study, Limosilactobacillus reuteri strain CGMCC 17942 and Lactiplantibacillus plantarum strain CGMCC 14407 were individually administered to lithogenic-diet (LD)-fed mice for 8 weeks. Both Lactobacillus strains significantly reduced LD-induced gallstones, hepatic steatosis, and hyperlipidemia. These strains modulated BA profiles in the serum and liver, which may be responsible for the activation of farnesoid X receptor (FXR). At the molecular level, L. reuteri and L. plantarum increased ileal fibroblast growth factor 15 (FGF15) and hepatic fibroblast growth factor receptor 4 (FGFR4) and small heterodimer partner (SHP). Subsequently, hepatic cholesterol 7α-hydroxylase (CYP7A1) and oxysterol 7α-hydroxylase (CYP7B1) were inhibited. Moreover, the two strains enhanced BA transport by increasing the levels of hepatic multidrug resistance-associated protein homologs 3 and 4 (Mrp3/4), hepatic multidrug resistance protein 2 (Mdr2), and the bile salt export pump (BSEP). In addition, both L. reuteri and L. plantarum reduced LD-associated gut microbiota dysbiosis. L. reuteri increased the relative abundance of Muribaculaceae, while L. plantarum increased that of Akkermansia. The changed gut microbiota was significantly negatively correlated with the incidence of cholesterol gallstones and the FXR-antagonistic BAs in the liver and serum and with the FXR signaling pathways. Furthermore, the protective effects of the two strains were abolished by both global and intestine-specific FXR antagonists. These findings suggest that Lactobacillus might relieve CGS through the FXR signaling pathways.

IMPORTANCE Cholesterol gallstone (CGS) disease is prevalent worldwide. None of the medical options for prevention and treatment of CGS disease are recommended, and surgical management has a high rate of recurrence. It has been reported that the factors involved in metabolic syndrome are highly connected with CGS formation. While remodeling of dysbiosis of the gut microbiome during improvement of metabolic syndrome has been well studied, less is known about prevention of CGS formation after regulating the gut microbiome. We used the lithogenic diet (LD) to induce an experimental CGS model in C57BL/6J mice to investigate protection against CGS formation by Limosilactobacillus reuteri strain CGMCC 17942 and Lactiplantibacillus plantarum strain CGMCC 14407. We found that these L. reuteri and L. plantarum strains altered the bile acid composition in mice and improved the dysbiosis of the gut microbiome. These two Lactobacillus strains prevented CGS formation by fully activating the hepatic and ileal FXR signaling pathways. They could be a promising therapeutic strategy for treating CGS or preventing its recurrence.

Endocrine-disruptor endpoints in the ovary and thyroid of adult female rats exposed to realistic doses of di-(2-ethylhexyl) phthalate

Di-(2-ethylhexyl) phthalate (DEHP) is the world's most widely used polyvinyl chloride (PVC) plasticizer and is used in virtually every category of flexible PVC. In fact, DEHP is extensively used in food cosmetics and medical packaging. It has become a serious problem in recent years. DEHP can be absorbed into the human body through the air, food, water, and skin. The current study involved intraperitoneal injection of DEHP dissolved in corn oil once daily for 21 consecutive days to investigate the effects of DEHP on the thyroid and the reproductive system in female rats. Results show that ovarian hormones (progesterone and estrogen) decreased significantly in the rats treated with DEHP compared to control. This result is supported by the alteration of folliculogenesis, the decrease of the follicles viability, and the apoptosis of the granulosa cells observed on histological sections of ovary and thyroid in female rats exposed to low doses of DEHP. Histopathological study revealed that DEHP could damage thyroid tissue and disrupt these functions. We also observed cellular damage, particularly in the liver cells, and a significant increase in biochemical parameters such as alanine aminotransferase (ALT) and aspartate aminotransferase (AST) compared to the control group.

Lactic acid bacteria alleviate di-(2-ethylhexyl) phthalate-induced liver and testis toxicity via their bio-binding capacity, antioxidant capacity and regulation of the gut microbiota

Di-(2-ethylhexyl) phthalate (DEHP) is a plasticiser that, if absorbed into the human body, can cause various adverse effects including reproductive toxicity, liver toxicity and gut microbiota dysbiosis. So far, some studies have proved that the toxicity of DEHP can be reduced by using antioxidants. However, these candidates all show potential side effects and cannot prevent the accumulation of DEHP in the body, making them unable to be used as a daily dietary supplement to relieve the toxic effects of DEHP. Lactic acid bacteria (LAB) have antioxidant capacity and the ability to adsorb harmful substances. Herein, we investigated the protective effects of five strains of LAB, selected based on our in vitro assessments on antioxidant capacities or bio-binding capacities, against the adverse effects of DEHP exposure in rats. Our results showed that LAB strains with outstanding DEHP/MEHP binding capacities, Lactococcus lactis subsp. lactis CCFM1018 and Lactobacillus plantarum CCFM1019, possess the ability to facilitate the elimination of DEHP and its metabolite mono-(2-ethylhexyl) phthalate (MEHP) with the faeces, decrease DEHP and MEHP level in serum further. Meanwhile, DEHP-induced liver and testicular injuries were effectively alleviated by CCFM1018 and CCFM1019. In addition, CCFM1018 effectively alleviated the DEHP-induced oxidative stress with its strong antioxidant ability. Furthermore, both CCFM1018 and CCFM1019 modulated the gut microbiota, which in turn increased the concentrations of faecal propionate and butyrate and regulated the pathways related to host metabolism. Correlation analysis indicate that DEHP/MEHP bio-binding capacity of LAB plays a crucial role in protecting the body from DEHP exposure, and its antioxidant capacity and the ability to alleviate the gut microbiota dysbiosis are also involved in the alleviation of damage. Thus, LAB with powerful bio-binding capacity of DEHP and MEHP can be considered as a potential therapeutic dietary strategy against DEHP exposure.

Taraxasterol ameliorates dextran sodium sulfate-induced murine colitis via improving intestinal barrier and modulating gut microbiota dysbiosis

Taraxasterol (TAX) has been proven to prevent and treat inflammatory diseases. However, the effects of TAX on intestinal barrier and the diversity, structure, and function of gut microbiota have yet to be elucidated in dextran sodium sulfate (DSS)-induced colitis mice. Our objectives are to evaluate the effect of TAX on intestinal barrier and its impact on gut microbiota. Herein, immunofluorescence analysis is conducted to determine the expressions of tight junction (ZO-1) and mucin (Mucin-2) proteins. The abundance, diversity, and function of fecal colonies are investigated by using 16S rDNA sequencing, and the influence of TAX on the gut microbiota in mice is also analyzed. Our results suggest that TAX attenuates the symptoms in DSS-induced colitis mice by reducing the DAI score, increasing colon length, alleviating histopathological damage of colon tissues, and improving intestinal barrier. 16S rDNA sequencing of fecal samples indicates that TAX intervention has a regulatory effect on DSS-induced gut microbiota dysbiosis at different taxonomic levels. TAX increases microbial diversity that is reduced by DSS. It normalizes the relative abundance of and the ratio of /. In addition, treatment with TAX has a better effect on the function of metabolisms, such as nucleotide, lipid, and bile acid metabolism. These findings suggest that TAX may be a good candidate for the remission of colitis, which is related to improving intestinal barrier and modulating gut microbiota.

Multiple transcriptomic profiling: potential novel metabolism-related genes predict prepubertal testis damage caused by DEHP exposure

The toxic effect of di(2-ethylhexyl) phthalate (DEHP) on prepubertal testes was examined in this study. We treated 3-week-old male mice with 4.8 mg/kg/day (milligram/kilogram/day) (no observed adverse effect level), 30 mg/kg/day (high exposure dose relative to humans), 100 mg/kg/day (level causing a reproductive system disorder), and 500 mg/kg/day (dose causing a multigenerational reproductive system disorder) of DEHP via gavage. Obvious abnormalities in the testicular organ coefficient, spermatogenic epithelium, and testosterone levels occurred in the 500 mg/kg DEHP group. Ribonucleic acid sequencing (RNA-seq) showed that differentially expressed genes (DEGs) in each group could enrich reproduction and reproductive process terms according to the gene ontology (GO) results, and coenrichment of metabolism pathway was observed by the Reactome pathway analysis. Through the analysis of common genes in the metabolism pathway, we discovered that DEHP exposure at 4.8 to 500 mg/kg or 100 mg/kg caused the same damages to the prepubertal testis. In general, we identified two key transcriptional biomarkers (fatty acid binding protein 3 (Fabp3) and carboxylesterase (Ces) 1d), which provided new insight into the gene regulatory mechanism associated with DEHP exposure and will contribute to the prediction and diagnosis of prepuberty testis injury caused by DEHP.

Impact of Contaminants on Microbiota: Linking the Gut-Brain Axis with Neurotoxicity

Over the last years, research has focused on microbiota to establish a missing link between neuronal health and intestine imbalance. Many studies have considered microbiota as critical regulators of the gut–brain axis. The crosstalk between microbiota and the central nervous system is mainly explained through three different pathways: the neural, endocrine, and immune pathways, intricately interconnected with each other. In day-to-day life, human beings are exposed to a wide variety of contaminants that affect our intestinal microbiota and alter the bidirectional communication between the gut and brain, causing neuronal disorders. The interplay between xenobiotics, microbiota and neurotoxicity is still not fully explored, especially for susceptible populations such as pregnant women, neonates, and developing children. Precisely, early exposure to contaminants can trigger neurodevelopmental toxicity and long-term diseases. There is growing but limited research on the specific mechanisms of the microbiota–gut–brain axis (MGBA), making it challenging to understand the effect of environmental pollutants. In this review, we discuss the biological interplay between microbiota–gut–brain and analyse the role of endocrine-disrupting chemicals: Bisphenol A (BPA), Chlorpyrifos (CPF), Diethylhexyl phthalate (DEHP), and Per- and polyfluoroalkyl substances (PFAS) in MGBA perturbations and subsequent neurotoxicity. The complexity of the MGBA and the changing nature of the gut microbiota pose significant challenges for future research. However, emerging in-silico models able to analyse and interpret meta-omics data are a promising option for understanding the processes in this axis and can help prevent neurotoxicity.

Characterization of the Antibacterial Activity of an SiO2 Nanoparticular Coating to Prevent Bacterial Contamination in Blood Products

Technological innovations and quality control processes within blood supply organizations have significantly improved blood safety for both donors and recipients. Nevertheless, the risk of transfusion-transmitted infection remains non-negligible. Applying a nanoparticular, antibacterial coating at the surface of medical devices is a promising strategy to prevent the spread of infections. In this study, we characterized the antibacterial activity of an SiO₂ nanoparticular coating (i.e., the “Medical Antibacterial and Antiadhesive Coating” [MAAC]) applied on relevant polymeric materials (PM) used in the biomedical field. Electron microscopy revealed a smoother surface for the MAAC-treated PM compared to the reference, suggesting antiadhesive properties. The antibacterial activity was tested against selected Gram-positive and Gram-negative bacteria in accordance with ISO 22196. Bacterial growth was significantly reduced for the MAAC-treated PVC, plasticized PVC, polyurethane and silicone (90–99.999%) in which antibacterial activity of ≥1 log reduction was reached for all bacterial strains tested. Cytotoxicity was evaluated following ISO 10993-5 guidelines and L929 cell viability was calculated at ≥90% in the presence of MAAC. This study demonstrates that the MAAC could prevent bacterial contamination as demonstrated by the ISO 22196 tests, while further work needs to be done to improve the coating processability and effectiveness of more complex matrices.

Sodium butyrate alleviates cholesterol gallstones by regulating bile acid metabolism

Cholesterol overloading and bile acid metabolic disorders play an important role in the onset of cholesterol gallstone (CGS). Short-chain fatty acids (SCFAs) can regulate bile acid metabolism by modulating the gut microbiota. However, the role and mechanism by which sodium butyrate (NaB) targets bile acids to attenuate CGS are still unknown. In this study, continuous administration of 12 mg/day for 8 weeks was decreased the incidence of gallstones induced by lithogenic diet (LD) from 100% to 25%. NaB modulated SCFAs and improved the gut microbiota. The remodeling of the gut microbiota changed the bile acid compositions and decreased cecal tauro-α-muricholic acid (T-α-MCA) and tauro-β-muricholic acid (T-β-MCA) which are effective farnesoid X receptor (FXR) antagonists. The quantitative real-time PCR examination showed that NaB significantly increased levels of ileal Fxr, fibroblast growth factor-15 (Fgf-15) and small heterodimer partner (Shp) mRNA and subsequently inhibited bile acid synthesis. In addition, NaB enhanced bile acid excretion by increasing the levels of hepatic multidrug resistance protein 2 (Mdr2) and bile salt export pump (Bsep) mRNA, and it enhanced bile acid reabsorption in the intestine by increasing the levels of ileal bile acid transporter (Ibat) mRNA. In addition, NaB reduced the absorption of cholesterol in the intestine and inhibited the excretion of cholesterol in the liver, which reduced the cholesterol concentration in serum and bile. Furthermore, the protective effects of NaB administration were abolished by FXR antagonists. Taken together, our results suggest that NaB mitigates CGS by modulating the gut microbiota to regulate the FXR-FGF-15/SHP signaling pathway.

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.

Effects of Xian-Ling-Gu-Bao capsule on the gut microbiota in ovariectomized rats: Metabolism and modulation

Xian-Ling-Gu-Bao capsule (XLGB) has been proven to prevent and treat osteoporosis. However, as a long-term oral formula, XLGB's effects on the metabolic capacity, structure and function of gut microbiota have yet to be elucidated in ovariectomized (OVX) rats. Our objectives were to evaluate the capacity of gut microbiota for metabolizing XLGB ingredients and to assess the effect of this prescription on gut microbiota. Herein, an integrated analysis that combined ultrahigh-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) and ultrahigh-performance liquid chromatography tandem triple quadrupole mass spectrometry (UPLC-TQD-MS) was conducted to determine the metabolic capacity of gut microbiota. The effects of XLGB on gut microbiota were explored by metagenomic sequencing in OVX rats. Fecal samples from each group were collected after intragastric administration for three months. In total, 64 biotransformation products were fully characterized with rat gut microbiota from the OVX group and the XLGB group. The deglycosylation reaction was the main biotransformation pathway in core structures in the group that was incubated with XLGB. Compared with the OVX group, different biotransformation products and pathways of the XLGB group after incubation for 2 h and 8 h were described. After three months of feeding with XLGB, the domesticated gut microbiota was conducive to the production of active absorbed components via deglycosylation, such as icaritin, psoralen and isopsoralen. Comparisons of the gut microbiota of the OVX and XLGB groups showed differences in the relative abundances of the two dominant bacterial divisions, namely, Firmicutes and Bacteroidetes. The proportion of Firmicutes was significantly lower and that of Bacteroidetes was significantly higher in the XLGB group. This result demonstrated that XLGB could provide a basis for the treatment of osteoporosis by regulating lipid and bile acid metabolism. In addition, the increase in Lactobacillus, Bacteroides and Prevotella could be an important factor that led to easier production of active absorbed aglycones in the XLGB group. Our observation provided further evidence of the importance of gut microbiota in the metabolism and potential activity of XLGB.

Postnatal exposure to DINP was associated with greater alterations of lipidomic markers for hepatic steatosis than DEHP in postweaning mice

The toxicity of the endocrine disruptor di(2-ethylhexyl) phthalate (DEHP) has been extensively studied for its hormonal dysregulation, obesogenic effect and associated metabolic diseases. DEHP's primary substitute di-isononyl phthalate (DINP), however, although increased in annual production globally, requires better understanding of its health effect. Our previous work reported disruptions in plasma lipid profiles, but the metabolic responses following phthalate exposure in the liver, particularly the entire hepatic lipidome, have been lacking. A targeted lipidomic technique was applied to accurately quantify a total of 363 lipid species in the liver of neonatal mice after exposure to a daily dose of 4.8 mg/kg body weight/day from birth throughout lactation. Distinct patterns of disruption for each sum of lipid classes or sub-classes between the genders were the most noticeable. Following DINP administration, female pups were subject to greater changes in phosphatidylethanolamines, bis(monoacylglycero)phosphate and ceramides. In contrast, the males exhibited less changes in the phosphoglycerol backbone-based molecules, whereas glycerol and cholesterol esters were more disrupted by DINP. DEHP, however, induced less changes overall compared to DINP. These findings highlighted the predominant lipidomic disruption of DINP on glycerol (diacylglycerides and triacylglycerides) and/or cholesterol (in ester or free form) molecules in neonatal mice across genders, suggesting the genesis of hepatic steatosis occurring at as early as post weaning. Collectively, these findings question the suitability of DINP as a safe DEHP substitute and warrant further investigation on longer-term exposure to elucidate its effect on chronic liver diseases.

Adipose Tissue and Endocrine-Disrupting Chemicals: Does Sex Matter?

Obesity and metabolic-related diseases, among which diabetes, are prominent public health challenges of the 21st century. It is now well acknowledged that pollutants are a part of the equation, especially endocrine-disrupting chemicals (EDCs) that interfere with the hormonal aspect. The aim of the review is to focus on adipose tissue, a central regulator of energy balance and metabolic homeostasis, and to highlight the significant differences in the endocrine and metabolic aspects of adipose tissue between males and females which likely underlie the differences of the response to exposure to EDCs between the sexes. Moreover, the study also presents an overview of several mechanisms of action by which pollutants could cause adipose tissue dysfunction. Indeed, a better understanding of the mechanism by which environmental chemicals target adipose tissue and cause metabolic disturbances, and how these mechanisms interact and sex specificities are essential for developing mitigating and sex-specific strategies against metabolic diseases of chemical origin. In particular, considering that a scenario without pollutant exposure is not a realistic option in our current societies, attenuating the deleterious effects of exposure to pollutants by acting on the gut-adipose tissue axis may constitute a new direction of research.