Di-(2-ethylhexyl)-phthalate induces glucose metabolic disorder in adolescent rats

Biochemical responses and antioxidant defense mechanisms in Channa Striatus exposed to Bisphenol S

Bisphenol S (BPS), a BPA analog and a safer alternative, is utilized in a diverse range of industrial applications, such as making polycarbonate plastics, epoxy resins, thermal receipt papers, and currency bills. Recently, the increased use of BPS in containers and packages for daily life has been interrogated due to its identical chemical structure and probable endocrine-disrupting actions as BPA has. The present study aimed to evaluate the alterations in biochemical indices and antioxidant enzymes as certain indicators of the endocrine-disrupting effect of BPS in Channa striatus, a freshwater fish. BPS-exposed fish species were subjected to three sub-lethal concentrations of BPS (1, 4, and 12 ppm) and observed after an interval of 7 and 21 days. Exposure to BPS caused a reduction in the level of protein in muscle, gonads and the liver due to an impairment of protein synthesis. Levels of cholesterol in the muscle, gonads, and liver of BPS-exposed fish were found to be decreased after treatment, indicating either an inhibition of cholesterol biosynthesis in the liver or reduced absorption of dietary cholesterol. The levels of antioxidant enzymes such as superoxide dismutase, catalase, glutathione reductase and glutathione peroxidase showed remarkable increases, while the activity of glutathione S-transferase decreased considerably, indicating the antioxidant defense mechanism to counteract the oxidative stress induced by BPS. Moreover, a significant increase was noted in the level of lipid peroxidation products, like malondialdehyde and conjugate diene, which represent biomarkers of oxidative stress. The histoarchitecture changes were also observed in the liver, muscle and gonads of BPS-treated fish species. The present study showed that sub-lethal exposure to BPS significantly influenced the activities of these enzymes and peroxidation byproducts. From this study, it is concluded that BPS-caused toxic effects in fish species lead to an imbalance in the antioxidant defense system. It is clearly indicated that BPS toxicity could lead to susceptible oxidative stress in various tissues and could damage vital organs.

The role of angiotensin I-converting enzyme gene polymorphism and global DNA methylation in the negative associations between urine di-(2-ethylhexyl) phthalate metabolites and serum adiponectin in a young Taiwanese population

BACKGROUND

Adiponectin is a key protein produced in adipose tissue, with crucial involvement in multiple metabolic processes. Di-(2-ethylhexyl) phthalate (DEHP), one of the phthalate compounds used as a plasticizer, has been shown to decrease adiponectin levels in vitro and in vivo studies. However, the role of angiotensin I-converting enzyme (ACE) gene polymorphism and epigenetic changes in the relationship between DEHP exposure and adiponectin levels is not well understood.

METHODS

This study examined the correlation between urine levels of DEHP metabolite, epigenetic marker 5mdC/dG, ACE gene phenotypes, and adiponectin levels in a sample of 699 individuals aged 12-30 from Taiwan.

RESULTS

Results showed a positive relationship between mono-2-ethylhexyl phthalate (MEHP) and 5mdC/dG, and a negative association between both MEHP and 5mdC/dG with adiponectin. The study found that the inverse relationship between MEHP and adiponectin was stronger when levels of 5mdC/dG were above the median. This was supported by differential unstandardized regression coefficients (- 0.095 vs. - 0.049, P value for interaction = 0.038)). Subgroup analysis also showed a negative correlation between MEHP and adiponectin in individuals with the I/I ACE genotype, but not in those with other genotypes, although the P value for interaction was borderline significant (0.06). The structural equation model analysis indicated that MEHP has a direct inverse effect on adiponectin and an indirect effect via 5mdC/dG.

CONCLUSIONS

In this young Taiwanese population, our findings suggest that urine MEHP levels are negatively correlated with serum adiponectin levels, and epigenetic modifications may play a role in this association. Further study is needed to validate these results and determine causality.

Comprehensive investigation of hepatotoxicity of the mixture containing phthalates and bisphenol A

Connections between the mixture containing bis(2- ethylhexyl) phthalate (DEHP), dibutyl phthalate (DBP) and bisphenol A (BPA) and liver injury were explored through in silico investigation and 2 in vivo models. Comparative Toxicogenomics Database (CTD), ShinyGO, ToppCluster and Cytoscape were used for bioinformatic analysis. In vivo subacute study was performed on rats - five groups (n = 6): (1) Control: corn oil, (2) DEHP: 50 mg/kg b.w./day, (3) DBP: 50 mg/kg b.w./day, (4) BPA: 25 mg/kg b.w./day, (5) MIX: DEHP + DBP + BPA. Zebrafish embryos were exposed to the investigated substances in different doses, singularly and combined (binary and ternary mixtures). Liver injury was linked to 75 DEHP, DBP, and BPA genes, mostly connected to inflammation/oxidative stress. In rats, significant alterations in redox status/bioelements and pathohistology were most notable or exclusively present in MIX (probable additive effects). BPA decreased liver area (LA) index in dose-dependent manner. DEHP (< 2 µg/mL) and DBP (≤ 5 µg/mL) reduced LA values, while their higher doses increased LA index. The effect of DBP in binary mixtures led to a lethal outcome at the two highest concentrations, while the hepatotoxicity of DEHP/DBP/BPA mixture was dictated by BPA (confirmed by the benchmark dose analysis).

Early-life exposure to di (2-ethyl-hexyl) phthalate: Role in children with endocrine disorders

Di (2-ethyl-hexyl) phthalate (DEHP), one of endocrine-disrupting chemicals (EDCs), has widespread concern due to its serious health hazards. Exposure to DEHP in the early stage of life affects fetal metabolic and endocrine function, which even would cause genetic lesions. To date, it is widely believed that the increasing incidence of childhood obesity and diabetes in adolescents is related to the impact of DEHP on glucose and lipid homeostasis in children. However, there remains a knowledge gap to recognize these adverse effects. Thus, in this review, besides the exposure routes and levels of DEHP, we further outline the effects of early-life exposure to DEHP on children and potential mechanisms, focusing on the aspect of metabolic and endocrine homeostasis.

Toxic effects of polyethylene microplastics on transcriptional changes, biochemical response, and oxidative stress in common carp (Cyprinus carpio)

Aquatic ecosystems have become a place for accumulating microplastics (MPs). MPs can directly or indirectly damage organisms. Although studies of the toxicity of MPs, there are insufficient literature reports on the effects of MPs on freshwater aquatic life. Therefore, this study aimed to evaluate the effect of MPs toxicity on Cyprinus carpio. In this study, biochemical parameters, oxidative biomarkers, and gene expression were assayed in fish exposed to 0, 175, 350, 700, and 1400 μg L^-1 of MPs for 30 days. MPs were detected in the liver and intestine of fish using FTIR-analysis. Mt1, Ces2, and P450 mRNA expression were enhanced in the hepatocytes of fish exposed to MPs, while Mt2 gene expression was significantly decreased. After exposure to MPs, MDA and carbonyl protein levels were higher than those of the reference group. The antioxidant capacity and glycogen contents in the hepatocytes significantly declined. MPs significantly inhibited glutathione reductase (GR), glucose 6-phosphate dehydrogenase (G6PDH), and catalase (CAT) activities. However, superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities increased. MPs decreased the total protein, globulin levels, and butyrylcholinesterase (BChE) activity in blood. In contrast, aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyl transferase (GGT), lactate dehydrogenase (LDH), alkaline phosphatase (ALP), and creatine phosphokinase (CPK) activities increased in treated-fish with MPs. Glucose, creatinine, cholesterol and triglyceride concentrations in fish exposed to MPs were significantly higher than that of the reference group. Consequently, MPs exposure could disrupt biochemical homeostasis, oxidative stress and alter the expression of genes involved in detoxification.

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.

Endogenous phthalates as a prospective regulator of interspecific relations in a biocoenosis

It is widely believed that phthalates are xenobiotic pollutants whose prevalence in the environment is associated with their facilitated diffusion from plastic materials. Studies into the effect of synthetic phthalates on living organisms revealed their extremely negative action on the metabolism of animals and humans. The acting mechanism of these compounds is realised through a ligand-receptor pathway. Along with dioxins, polychlorinated biphenyls and similar compounds, phthalates are classified as endocrine disrupters. However, at present, sufficient evidence has been accumulated confirming the natural origin of phthalates. Thus, phthalates were de novo biosynthesised from labelled precursors in an algae culture. These compounds were detected in closed experimental systems, including cell cultures of highest plants, as well as those isolated from a number of bacterial, fungi, lowest and highest plant forms located far from the sources of technogenic pollution. The concept of phthalate biogenesis assumes the action of these compounds on living systems. Phthalates exhibit bactericidal and fungicidal action and compose allelopathic exudates, suppressing the growth of competing plant forms. Phthalates possess insecticidal and repellent properties. An analogy can be traced between the action of phthalates and endocrine disrupters of another chemical category, namely phytoestrogens, which regulate herbivorous mammal populations. A hypothesis is proposed about the biological role of endogenous plant phthalates representing secondary metabolic compounds. Exhibiting predominantly a shielding function, these compounds participate in the network of interactions between plants, animals, fungi and microorganisms. It should be noted that synthetic and endogenous phthalates are characterised by essential stereochemical differences, which can explain their different action on living organisms.

Effects of bisphenol a on hematological, serum biochemical, and histopathological biomarkers in bighead carp (Aristichthys nobilis) under long-term exposure

Bisphenol A (BPA) is one of the highest volume chemicals produced in the world and is frequently used in dental sealants, water bottles, food, and beverage packaging. Due to persistent applications, BPA has become a potential threat to a variety of organisms including public health. In this study, a total of 80 bighead carps were randomly placed in different four groups (A-D). Fish in groups B, C, and D were exposed to BPA @500, 1000, and 1500 μg/L, respectively for 60 days. Fish in group A served as an untreated control group. The body weight was significantly decreased while the absolute and relative weight of different visceral organs increased significantly (p < 0.05) in fish exposed to higher concentration (1500 μg/L) of BPA. Results on proximate analysis showed significantly lower values of crude proteins, lipids, and moisture contents while increased contents of ash in muscles of treated fish. The erythrocyte counts, hemoglobin concentration, lymphocytes, and monocytes significantly decreased while total leukocyte and neutrophil counts significantly increased in treated fish. Results exhibited that different serum biochemistry parameters like serum albumin and total proteins decreased significantly (p < 0.05) while alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP), urea, creatinine, glucose, cholesterol, and lactate dehydrogenase (LDH) increased significantly (p < 0.05) in treated fish. Histopathological ailments like pyknosis, degeneration of glomeruli, increased Bowman's space, ceroid formation in kidneys while ceroid formation, hemorrhages, pyknosis, karyorrhexis, karyolysis, nuclear hypertrophy, and eccentric nuclei were observed in the liver of treated fish. Histological observation of different sections of the brain of treated fish exhibited degeneration of neurons in the cerebellum, lipofuscin deposition, microgliosis, necrotic neurons, inflammatory cells, and hemorrhage. Results on light microscopic observation of different sections of the heart of bighead carp revealed necrosis, inflammatory reaction, neutrophilic myocarditis, and hemorrhages. In conclusion, it is suggested that BPA induces adverse effects on physical, blood-biochemical parameters, and histopathological changes in multiple visceral tissues of exposed fish.

Integrating in silico with in vivo approach to investigate phthalate and bisphenol A mixture-linked asthma development: Positive probiotic intervention

The aim of this study was to explore the mechanisms of bis(2- ethylhexyl) phthalate (DEHP), dibutyl phthalate (DBP) and bisphenol A (BPA) mixture-induced asthma development and test probiotic as a potential positive intervention. Comparative Toxicogenomics Database (CTD) and ToppGene Suite were used as the main tools for in silico analysis. In vivo 28-day experiment was conducted on rats - seven groups (n = 6): (1) Control: corn oil, (2) P: probiotic (8.78 * 10⁸ CFU/kg/day); (3) DEHP: 50 mg/kg b.w./day, (4) DBP: 50 mg/kg b.w./day, (5) BPA: 25 mg/kg b.w./day; (6) MIX: DEHP + DBP + BPA; (7) MIX + P. Lungs, thymus and kidneys were extracted and prepared for redox status and essential metals analysis. By conducting additional in vitro experiment, probiotic phthalate and BPA binding ability was explored. There were 24 DEHP, DBP and BPA asthma-related genes, indicating the three most probable mechanisms - apoptosis, inflammation and oxidative stress. In vivo experiment confirmed that significant changes in redox status/essential metal parameters were either prominent, or only present in the MIX group, indicating possible additive effects. In vitro experiment confirmed the ability of the multy-strain probiotic to bind DEHP/DBP/BPA mixture, while probiotic administration ameliorated mixture-induced changes in rat tissue.

Integrated metabolomics and transcriptomics reveal di(2-ethylhexyl) phthalate-induced mitochondrial dysfunction and glucose metabolism disorder through oxidative stress in rat liver

Di(2-ethylhexyl) phthalate (DEHP) is a ubiquitous pollutant that results in hepatotoxicity. However, an understanding of the systematic mechanism of hepatic injury caused by DEHP remains limited. Here, we performed a comprehensive metabolomics and transcriptomics analyses to describe hepatic responses of rats to long-term DEHP exposure and, together with pathology and functional injury of liver, systematically analyzed the pathogenesis and mechanisms of liver damage. SD rats were exposed to 0 and 600 mg/kg/day DEHP for 12 weeks. Thereafter, biochemical indicators and histopathological changes regarding liver function were detected. Metabolomics and transcriptomics profiles of rat liver samples were analyzed using a UPLC-MS/MS system and Illumina Hiseq 4000, respectively. DEHP induced hepatocyte structural alterations and edema, depressed monooxygenase activity, decreased antioxidant activities, aggravated oxidative damage, blocked the tricarboxylic acid cycle and respiratory chain, and disturbed glucose homeostasis in the liver. These findings indicate that reactive oxygen species play a major role in these events. Overall, this study systematically depicts the comprehensive mechanisms of long-term DEHP exposure to liver injury and highlights the power of metabolomics and transcriptomics platforms in the mechanistic understanding of xenobiotic hepatotoxicity.

Intermittent fasting ameliorates di-(2-ethylhexyl) phthalate-induced precocious puberty in female rats: A study of the hypothalamic-pituitary-gonadal axis

Di-(2-ethylhexyl) phthalate has been reported to interfere with the development and function of animal reproductive systems. However, hardly any studies provide methods to minimize or prevent the adverse effects of DEHP on reproduction. The energy balance state of mammals is closely related to reproductive activities, and the reproductive axis can regulate reproductive activities according to changes in the body's energy balance state. In this study, the effects of every other day fasting (EODF), as a way of intermittent fasting, on preventing the precocious puberty induced by DEHP in female rats was studied. EODF significantly improved the advancement of vaginal opening age (as the markers of puberty onset) and elevated serum levels of luteinizing hormone and estradiol (detected by ELISA) induced by 5 mg kg^-1 DEHP exposure (D5). The mRNA and western blot results showed that the EODF could minimized the increase of gonadotropin-releasing hormone expression induced by DEHP exposure. The administration of DEHP could elevate the levels of kisspeptin protein and the number of kisspeptin-immunoreactive neurons in anteroventral periventricular nucleu, and this increase was diminished considerably by EODF treatment. In contrast, the D5 and D0 groups showed no remarkable difference in the level of Kiss1 expression in arcuate nucleus, whereas the D5 + EODF group had a remarkable decrease in kisspeptin expression as compared with the other two groups. Our results indicated that EODF might inhibit the acceleration of puberty onset induced by DEHP exposure via HPG axis.

Bisphenol A induced toxicity in blood cells of freshwater fish Channa punctatus after acute exposure

The widespread use of bisphenol A (BPA) has led to its ubiquity in the natural environment. It is extensively incorporated into different industrial products and is associated with deleterious health effects on both public and wildlife. The current trial was conducted to determine the toxic potential of bisphenol A using various parameters viz haematological, biochemical, and cytological in freshwater fish Channa punctatus. For this purpose, fish were exposed to 1.81 mg/l (1/4 of LC₅₀) and 3.81 mg/l (1/2 of LC₅₀) of BPA along with positive (acetone) and negative controls (water) for 96 h. The blood samples were collected at 24, 48, 72, and 96 h post-exposure. Compared to the control group, fish after acute exposure to BPA showed a significant decrease in HB content, number of red blood cells, PCV values whereas a significant increase in WBCs count was recorded with an increase in the exposure period. Besides, oxidative stress (determined as malondialdehyde content) increased as BPA concentration increased. Further, the activity of different antioxidant enzymes like catalase, and superoxide dismutase decreased significantly after treatment. Results also showed significantly increased frequency of morphological alterations, nuclear changes, and increased DNA damage potential of BPA in red blood cells. Further structural analysis of erythrocytes in maximally damaged group using Scanning Electron Microscopy was performed. The study concludes that BPA exhibits genotoxic activity and oxidative stress could be one of the mechanisms leading to genetic toxicity.

Promotion effects of DEHP on hepatocellular carcinoma models: up-regulation of PD-L1 by activating the JAK2/STAT3 pathway

Di(2-ethylhexyl) phthalate (DEHP), as an endocrine disruptor, is often used as a plasticizer in various polyvinyl chloride plastic products and medical consumables. Epidemiological studies have shown that long-term large intake of DEHP may be a risk factor for liver dysfunction. Long-term exposure to DEHP is associated with liver disease and aggravates the progression of chronic liver injury. However, the effects of DEHP on hepatocellular carcinoma (HCC) are rarely studied. In this study, we sought to determine the effects of DEHP on HCC induced by carbon tetrachloride combined with diethylnitrosamine, and further study its molecular mechanism. It was found that DEHP exposure significantly promotes tumor immune escape and activates signaling pathways involved in related protein expression of tumor immune escape, including PD-L1, JAK2, and STAT3. In addition, the trends observed in the HepG2 cells assay are consistent with vivo conditions. In summary, DEHP may play a tumor-promoting role in HCC mice and IFN-γ stimulated HepG2 cells, which may be related to the JAK2/STAT3 signaling pathway.

Evaluation of Oxidative stress, antioxidant enzymes and genotoxic potential of bisphenol A in fresh water bighead carp (Aristichthys nobils) fish at low concentrations

Bisphenol A (BPA) is one of the emerging contaminants associated with deleterious health effects on both public and wildlife and is extensively incorporated into different industrial products. Therefore, the current trial was conducted to determine the oxidative stress, status of different antioxidant enzymes and genotoxic potential of bisphenol A in fresh water fish at low concentrations. For this purpose, a total of 80 fresh water bighead carp (Aristicthys nobilis) received from commercial fish center were randomly divided and kept in four groups (A-D). Fish in groups (B-D) were exposed to different levels of BPA for a period of 60 days while fish of group A served as control group. Treated fish exhibited different physical and behavioral ailments in a time and treatment manners. Results showed significantly (p < 0.05) increased quantity of different oxidative stress biomarkers such as thiobarbituric acid reactive substance (TBARS), reduced glutathione (GSH) and the contents of reactive oxygen species (ROS) in gills, liver, kidneys and brain of exposed fish. Concentration of different antioxidant enzymes like catalase, superoxide dismutase, peroxidase and total proteins was significantly (p < 0.05) decreased in gills, liver, kidneys and brain of exposed fish. Results showed significantly (p < 0.05) increased frequency of morphological alterations, nuclear changes in red blood cells and increased DNA damage potential of bisphenol A in gills, liver, kidneys and brain tissues. The current trial concludes that even at very low concentrations bisphenol A causes toxic effects via turbulences in physiological and biochemical parameters in multiple tissues of fish.

Multi-strain probiotic ameliorated toxic effects of phthalates and bisphenol A mixture in Wistar rats

Phthalates and bisphenol A, to which people are mainly exposed through food, interfere with the body's endocrine system, along with various other toxic effects. Literature data suggest that probiotic cultures might be able to decrease the adverse effects of toxic substances by various mechanisms. The aim of this study was to investigate if treatment with multi-strained probiotic could reduce the toxicity of phthalates and bisphenol A mixture in Wistar rats. Animals were divided into four experimental groups (n = 6): (1) Control (corn oil); (2) P (probiotic (8.78 * 10⁸ CFU/kg/day): Saccharomyces boulardii + Lactobacillus rhamnosus + Lactobacillus planarum LP 6595+ Lactobacillus planarum HEAL9); (3) MIX (50 mg/kg b.w./day DEHP + 50 mg/kg b.w/day DBP + 25 mg/kg b.w./day BPA); (4) MIX + P. Animals were euthanized after 28 days of daily oral gavage treatment; blood and organs were collected for further analysis. Probiotic reduced systemic inflammation and had protective effects on liver, kidneys, spleen, lipid status and serum glucose level. It almost completely annulled the changes in biochemical, hematological and hormonal parameters and mitigated changes in relative liver size, food consumption and organ histology. These results suggest considering multi-strained probiotics as a dietary therapeutic strategy against toxicity of the investigated mixture.

Inhibition of JAK2/STAT3/SOCS3 signaling attenuates atherosclerosis in rabbit

Background

Previous studies have indicated that the JAK/STAT signaling pathway is involved in modulating arterial adventitia inflammation response. In this study, we designed experiments to further investigate the effect of JAK2/STAT3/SOCS3 signaling in rabbit atherosclerosis process.

Methods

Atherosclerosis was induced in the abdominal arteries of rabbits by balloon injury of the aorta supplemented by the atherogenic diet. Simultaneously, in the process of atherosclerosis, animals underwent either ruxolitinib treatment or not for 12 weeks. At the end of the experimental period, all rabbits were sacrificed. The plaque areas in abdominal artery, the lipid burden of plaque and the calcium burden of plaque were detected by H&E staining, Oil Red O staining and Alizarin Red staining, respectively. In addition, rabbit plasma lipids and inflammatory cytokines were measured by biochemical test kits or ELISA kits. Finally, the expression and phosphorylation levels of JAK2/STAT3/SOCS3 pathway-related proteins were detected by RT-qPCR, western blot and immunohistochemistry assays.

Results

H&E staining and CT scan analysis showed that rabbit atherosclerosis model was constructed successfully. Ruxolitinib, an inhibitor of the Janus kinase 2 (JAK2), substantially reduced the area of atherosclerotic plaques in rabbits treated with high fat diet and balloon injury of the aorta. Moreover, ruxolitinib significantly decreased IL-6, IL-1β, IFN-γ and TNF-α, but increased IL-10 and IL-17 levels in plasma of atherosclerotic rabbits. Additionally, ruxolitinib reduced plasma TC, TG and LDL-C contents and AIP value, while enhanced HDL-C level in atherosclerotic rabbits. Furthermore, we found that JAK2 and STAT3 phosphorylation were up-regulated in rabbits with atherosclerosis when compared with those of the control group, followed by the expression of SOCS3 was also increased due to the activation of JAK2 and STAT3. Interestingly, ruxolitinib could inactivate JAK2 and STAT3 pathway and decrease SOCS3 expression.

Conclusion

Taken together, the inhibition of JAK2/STAT3/SOCS3 signaling pathway may be a novel method for the clinical treatment of artery atherosclerosis.

Prenatal low-dose DEHP exposure induces metabolic adaptation and obesity: Role of hepatic thiamine metabolism

Di-(2-ethylhexyl)-phthalate (DEHP) is a ubiquitous environmental pollutant and is widely used in industrial plastics. However, the long-term health implications of prenatal exposure to DEHP remains unclear. We set out to determine whether prenatal DEHP exposure can induce metabolic syndrome in offspring and investigate the underlying mechanisms. A mouse model of prenatal DEHP exposure (0.2, 2, and 20 mg/kg/day) was established to evaluate the long-term metabolic disturbance in offspring. The mice were profiled for the hepatic metabolome, transcriptome and gut microbiota to determine the underlying mechanisms. Thiamine supplementation (50 mg/kg/day) was administered to offspring to investigate the role of thiamine in ameliorating metabolic syndrome. Prenatal exposure to low-dose DEHP (0.2 mg/kg/day) resulted in metabolic syndrome, including abnormal adipogenesis, energy expenditure and glucose metabolism, along with dysbiosis of the gut microbiome, in male offspring. Notably, hepatic thiamine metabolism was disrupted in these offspring due to the dysregulation of thiamine transport enzymes, which caused abnormal glucose metabolism. Prenatal low-dose DEHP exposure caused life-long metabolic consequences in a sex-dependent manner, and these consequences were be attenuated by thiamine supplementation in offspring. Our findings suggest low-dose DEHP exposure during early life stages is a potential risk factor for later obesity and metabolic syndrome.

Toxic Effects of the Mixture of Phthalates and Bisphenol A-Subacute Oral Toxicity Study in Wistar Rats

Phthalates and bisphenol A, classified as endocrine disruptors, have weak estrogenic, anti-androgenic properties, and affect thyroid hormone regulation. The aim of this study on male rats was to compare the subacute toxic effects of low doses of single compounds (bis (2 -ethylhexyl) phthalate (DEHP), dibutyl phthalate (DBP), and bisphenol A (BPA)) with the effects of their mixture through different biochemical, hormonal, and hematological parameters. Rats were divided into five experimental groups: Control (corn oil), DEHP (50 mg/kg b.w./day), DBP (50 mg/kg b.w./day), BPA (25 mg/kg b.w./day), and MIX (50 mg/kg b.w./day DEHP + 50 mg/kg b.w/day DBP + 25 mg/kg b.w./day BPA). Animals were sacrificed after 28 days of oral treatment and blood was collected for further analysis. The results demonstrated that the mixture produced significant changes in lipid profile, liver-related biochemical parameters, and glucose level. Furthermore, the opposite effects of single substances on the thyroxine level have been shown in comparison with the mixture, as well as a more pronounced effect of the mixture on testosterone level. This study contributes to the body of knowledge on the toxicology of mixtures and gives one more evidence of the paramount importance of mixture toxicity studies, especially in assessing the endocrine disruptive effects of chemicals.

Developmental origins of type 2 diabetes: Focus on epigenetics

Traditionally, genetics and lifestyle are considered as main determinants of aging-associated pathological conditions. Accumulating evidence, however, suggests that risk of many age-related diseases is not only determined by genetic and adult lifestyle factors but also by factors acting during early development. Type 2 diabetes (T2D), an age-related disease generally manifested after the age of 40, is among such disorders. Since several age-related conditions, such as pro-inflammatory states, are characteristic of both T2D and aging, this disease is conceptualized by many authors as a kind of premature or accelerated aging. There is substantial evidence that intrauterine growth restriction (IUGR), induced by poor or unbalanced nutrient intake, exposure to xenobiotics, maternal substance abuse etc., may impair fetal development, thereby causing the fetal adipose tissue and pancreatic beta cell dysfunction. Consequently, persisting adaptive changes may occur in the glucose-insulin metabolism, including reduced capacity for insulin secretion and insulin resistance. These changes can lead to an improved ability to store fat, thus predisposing to T2D development in later life. The modulation of epigenetic regulation of gene expression likely plays a central role in linking the adverse environmental conditions early in life to the risk of T2D in adulthood. In animal models of IUGR, long-term persistent changes in both DNA methylation and expression of genes implicated in metabolic processes have been repeatedly reported. Findings from human studies confirming the role of epigenetic mechanisms in linking early-life adverse experiences to the risk for T2D in adult life are scarce compared to data from animal studies, mainly because of limited access to suitable biological samples. It is, however, convincing evidence that these mechanisms may also operate in human beings. In this review, theoretical models and research findings evidencing the role of developmental epigenetic variation in the pathogenesis of T2D are summarized and discussed.

Genotoxicity and glucose tolerance induction by acetyltriethylcitrate, substitute plasticizer compared to di(2-ethylhexyl)phthalate

As di(2-ethylhexyl) phthalate (DEHP), one of phthalates, is classified as probable human carcinogens in EPA, acetyltriethyl citrate(ATEC), one of aliphatic esters, could be applied to DEHP substitute. ATEC is used as plasticizers in cosmetics and nail products. Here, we studied whether ATEC might have genotoxic potential and induce glucose tolerance as compared to DEHP. Genotoxicity was determined by Ames test with histidine-requiring Salmonella typhimurium (TA98, TA100, TA1535 and TA1537) and tryptophan-requiring Escherichia coli (WP2uvrA(pKM101)) strains, chromosomal aberration assay with Chinese hamster lung(CHL/IU) cells, and micronucleus test with bone marrow cells of CD-1 mice. The number of revertants was not significantly changed in Ames test. The frequency of cells with chromosome aberrations was less than 5% in ATEC- or DEHP-treated cells for 6 or 24 h. In addition, no statistically significant increase was observed for the incidence of micronucleated polychromatic erythrocytes (MNPCE) in polychromatic erythrocytes (PCE) and for the ratio of PCE among total erythrocytes at 24 or 48 h after the treatment of mice with ATEC or DEHP. In the meanwhile, blood glucose level (BGL) was increased by the treatment of mice with DEHP or ATEC for 5 consecutive days. Additional 7 days later, BGL by DEHP was recovered to normal level, but not that by ATEC. Then, taken together, our results suggest that ATEC could disrupt glucose metabolism under our experimental conditions. Therefore, although DEHP and ATEC may not be genotoxic, our data should be helpful for persons with the problem in glucose metabolism to choose products containing DEHP or ATEC.

Effects of citrate ester plasticizers and bis (2-ethylhexyl) phthalate in the OECD 28-day repeated-dose toxicity test (OECD TG 407)

Citrate esters are considered functional alternatives to phthalate plasticizers, but their toxicity remains poorly understood. The toxicity of citrate esters, including triethyl 2-acetylcitrate (ATEC) and trihexyl O-acetylcitrate (ATHC), were examined together with that of bis (2-ethylhexyl) phthalate (DEHP) using the Organization for Economic Co-operation and Development Test Guideline 407 (OECD TG407). Following 28-day oral administration, no significant differences in body weight or the weight of the brain, pituitary, heart, epididymis, seminal vesicles, or coagulating gland were found between the vehicle control and DEHP, ATEC or ATHC groups. In the 400 mg/kg day DEHP group, liver, adrenal, thymus, spleen, kidney, testis, and prostate weights were significantly increased. In the 400 mg/kg day ATHC group, kidney, adrenal, thymus, testis and prostate weights were significantly increased. In the 400 mg/kg day ATEC group, kidney, adrenal and testis weights were significantly increased. Hepatocyte size was significantly increased in the 400 mg/kg day DEHP group, suggestive of hepatotoxicity, but was not increased in the ATEC or ATHC groups. There were no significant differences in white blood cell, red blood cell or platelet counts, hemoglobin concentrations, hematocrit, mean corpuscular volume, fasting glucose, insulin, or testosterone concentrations between the vehicle control and DEHP, ATEC and ATHC groups. In the ATHC 400 mg/kg day group, T3 was decreased while T4 was increased, suggestive of disruption of thyroid function. The results of the OECD TG407 subacute repeated dosing toxicity test indicate ATEC is less toxic compared to ATHC or DEHP and could be recommended as an alternative to phthalate plasticizers.

The effect of di-2-ethylhexyl phthalate on inflammation and lipid metabolic disorder in rats

BACKGROUND

Plasticizer di-2-ethylhexyl phthalate (DEHP) can induce lipid metabolic disorder. There was a chronic low level inflammatory response in adipose tissue of patients with lipid metabolic disorder. But the effect of inflammation on lipid metabolic disorder induced by DEHP is unclear. The present study was undertaken to explore the effect of di-2-ethylhexyl phthalate on inflammation and lipid metabolic disorder in rats.

METHODS

Eighty healthy 21-day-old Wistar rats were randomly divided into 4 groups and administered DEHP by gavage at 0, 5, 50, and 500 mg/kg/ d for 8 weeks. Morphological changes of adipose tissue, the levels of IL-1β, TNF-α, LEP, and ADP in rat serum and adipose tissue, the serum TC, TG, HDL-C and LDL-C, the mRNA and protein expression levels of lipid metabolism-related gene CEBP/β and inflammation-related gene CD68 were measured.

RESULTS

After exposure to DEHP, the weight of rats in the high dose group was significantly higher than that in the control group (p < 0.05). And the number of adipose tissue cells in the medium-dose and high-dose DEHP groups increased, with much more macrophage infiltrated. The levels of LDL-C, HDL-C, TC in serum and LEP in adipose tissue of rats exposed to 500 mg/kg DEHP were significantly higher than those in the control group (p < 0.05); while the level of ADP in adipose tissue in rats exposed to DEHP was significantly lower (p < 0.05). The levels of IL-1β and TNF-α in surum and adipose tissue of rats exposed to DEHP were significantly higher than those in the control group (p < 0.05). The mRNA and protein expression levels of CEBP/β and CD68 in adipose tissue of rats exposed to DEHP were significantly higher than those in the control group. The TC, LEP and ADP Levels of rats were significantly different among different subgroup of IL-1β and TNF-α, and in high level subgroup, the TC, LEP and ADP Levels were increased. The levels of TC and LEP was increased in high level subgroup of CD68.

CONCLUSION

DEHP induced more macrophage infiltrated in adipose tissue of rats, promoted the secretion of IL-1β, TNF-α and the formation of inflammation, and disturbed the normal lipid metabolism and lead to lipid metabolic disorders. What is more, the levels of inflammation were associated with the lipid levels.

Maternal di-(2-ethylhexyl) phthalate exposure alters hepatic insulin signal transduction and glucoregulatory events in rat F1 male offspring

Di-(2-ethylhexyl) phthalate (DEHP) is a commonly used plasticizer with endocrine disrupting properties. Its widespread use resulted in constant human exposure including fetal development and postnatal life. Epidemiological and experimental data have shown that DEHP has a negative influence on glucose homeostasis. However, the evidence regarding the effect of maternal DEHP exposure on hepatic glucose homeostasis is scarce. Hence, we investigated whether DEHP exposure during gestation and lactation disrupts glucose homeostasis in the rat F₁ male offspring at adulthood. Pregnant rats were divided into three groups and administered with DEHP (10 and 100 mg/kg/day) or olive oil from gestational day 9 to postnatal day 21 (lactation period) through oral gavage. DEHP-exposed offspring exhibited hyperglycemia, impaired glucose and insulin tolerances along with hyperinsulinemia at postnatal day 80. DEHP exposure significantly reduced the levels of insulin signaling molecules such as insulin receptors, IRS1, Akt and its phosphorylated forms. GSK3β and FoxO1 proteins increased in DEHP-exposed groups whereas its phosphorylated forms decreased. Treated groups showed decreased glycogen synthase activity and glycogen concentration. Glucose-6-phosphatase and phosphoenolpyruvate carboxykinase mRNA level and enzyme activity increased in DEHP-treated groups. The interaction between FoxO1-glucose-6-phosphatase and FoxO1-phosphoenolpyruvate carboxykinase was also increased. This study suggests that DEHP exposure impairs insulin signal transduction and alters glucoregulatory events leading to the development of type 2 diabetes in F₁ male offspring.

Impact of the Di(2-Ethylhexyl) Phthalate Administration on Trace Element and Mineral Levels in Relation of Kidney and Liver Damage in Rats

Di(2-ethylhexyl) phthalate (DEHP) is a widely used synthetic polymer in the industry. DEHP may induce reproductive and developmental toxicity, obesity, carcinogenesis and cause abnormal endocrine function in both human and wildlife. The aim of this study was to investigate trace element and mineral levels in relation of kidney and liver damage in DEHP-administered rats. Therefore, prepubertal male rats were dosed with 0, 100, 200, and 400 mg/kg/day of DEHP. At the end of the experiment, trace element and mineral levels, glucose-6-phosphate dehydrogenase (G6PD), 6-phosphogluconate dehydrogenase (6-PGD), glutathione reductase (GR) and glutathione S-transferase (GST) enzyme activities were evaluated in the serum, liver, and kidney samples of rats. Furthermore, serum clinical biochemistry parameters, organ/body weight ratios and histological changes were investigated to evaluate impact of DEHP more detailed. Our data indicated that sodium (Na), calcium (Ca), potassium (K), lithium (Li), rubidium (Rb) and cesium (Cs) levels significantly decreased, however iron (Fe) and selenium (Se) concentrations significantly increased in DEHP-administered groups compared to the control in the serum samples. On the other hand, upon DEHP administration, selenium concentration, G6PD and GR activities were significantly elevated, however 6-PGD activity significantly decreased compared to the control group in the kidney samples. Decreased G6PD activity was the only significant change between anti-oxidant enzyme activities in the liver samples. Upon DEHP administration, aberrant serum biochemical parameters have arisen and abnormal histological changes were observed in the kidney and liver tissue. In conclusion, DEHP may induce liver and kidney damage, also result abnormalities in the trace element and mineral levels.

Self-Assembling Hydrophilic Magnetic Covalent Organic Framework Nanospheres as a Novel Matrix for Phthalate Ester Recognition

The development of covalent organic framework (COF)-derived materials with additional functions and applications is highly desired. In this work, a unique COF-functionalized hydrophilic magnetic nanosphere (Fe₃O₄@PDA@TbBd) with Fe₃O₄ as a magnetic core, polydopamine (PDA) as a hydrophilic middle layer, and TbBd as an outer COF shell was facilely prepared as a novel hydrophilic platform for efficient detection of phthalic acid esters (PAEs). The resultant Fe₃O₄@PDA@TbBd nanosphere displayed strong magnetic response, high surface area, and good hydrophilicity. Accordingly, the newly synthesized COF exhibited great potential in phthalate analysis with a wide linearity (50-8000 ng/mL), good recovery (92.3-98.9%), a low limit of detection (0.0025-0.01 ng/mL), and a small relative standard deviation (for intraday less than 4.6% and for interday less than 6.8%). More excitingly, the new COF was applied to analyze nine PAEs in the human plasma sample. This work opens up new avenues for the development and application of functionalized COF-derived materials.