Di-(2-ethylhexyl) phthalate induced nephrotoxicity in quail (Coturnix japonica) by triggering nuclear xenobiotic receptors and modulating the cytochrome P450 system

New insights into DEHP-induced inflammatory injury in chicken spleen: ROS/TLR4/MyD88 pathway and apoptosis/necroptosis-M1 polarization crosstalk

The environmental endocrine disruptor di(2-ethylhexyl) phthalate (DEHP) is a plasticiser used in large quantities in plastics and is hazardous to the health of humans and various animals. DEHP can be immunotoxic to the spleen through oxidative stress. Still, the role of splenic macrophage polarization in lymphocyte apoptosis and necroptosis, whether they interact with each other, and the mechanism of the effect on splenic inflammatory injury are unknown. In this study, based on the construction of a time-and dose-dependent model of DEHP-exposed chicken spleen, chicken lymphoma cell (MSB-1) and chicken macrophage (HD11) models were established to investigate the mechanism of apoptosis/necroptosis-M1 polarization crosstalk in DEHP-induced toxicity in chicken spleen injury. The results showed that DEHP exposure activated the ROS/TLR4/MyD88 pathway, up-regulated the expression of chemokines, induced macrophage M1 polarization, caused apoptosis and necroptosis in lymphocytes and inflicted inflammatory damage to the spleen, however, these effects could be alleviated by NAC. DEHP exposure of the HD11/MSB-1 cell co-culture system showed that M1 polarization promoted apoptosis and necroptosis and vice versa. In conclusion, DEHP exposure is involved in mediating the crosstalk between apoptosis/necroptosis and M1 polarization through the activation of the ROS/TLR4/MyD88 pathway, which in turn exacerbates inflammatory injury in the chicken spleen.

Exploring the nephrotoxicity and molecular mechanisms of Di-2-ethylhexyl phthalate: A comprehensive review

Di-2-ethylhexyl phthalate (DEHP), a widely applied plasticizer in various products, can be absorbed into the human body through several channels and accumulate in the lungs, liver, testes, and kidneys, potentially impairing the function of these organs. Recently, the nephrotoxicity of DEHP has received heightened attention. Numerous epidemiologic findings have demonstrated that DEHP exposure may contribute to renal damage, leading to structural and functional abnormalities and exacerbating the progression of kidney disease. Recent research has discovered the mechanisms behind DEHP-induced nephrotoxicity may involve a variety of pathways, including apoptosis, autophagy, ferroptosis, oxidative stress, inflammation, DNA damage, and lipid metabolism disorders. This review discusses the impact of DEHP on kidney function and delves into the molecular mechanisms of nephrotoxicity mediated by DEHP in recent years. In addition, the review examines evidence for the antioxidant and anti-inflammatory capacities of lycopene, green tea polyphenols, and quercetin in ameliorating DEHP-induced renal injury is reviewed, providing a basis for further research.

Multi-omics analysis of the toxic effects on gill tissues of crucian carp (Carassius auratus) from chronic exposure to environmentally relevant concentrations of Di(2-ethylhexyl) phthalate (DEHP)

The pervasive use of the plasticizer di(2-ethylhexyl) phthalate (DEHP) poses potential risks to global aquatic ecosystems. This study systematically evaluated the adverse effects of chronic exposure to environmentally relevant concentrations of DEHP on gill tissues of crucian carp, utilizing histological examination, metabolomic, and transcriptomic analysis. The results demonstrated that DEHP induced significant histopathological alterations in gill tissues, with significant enrichment observed in multiple pathways associated with amino acid, hormone, lipid, and xenobiotic metabolism. Metabonomics-transcriptomics analyses indicated that DEHP-induced significantly over-activation of cytochrome P450 1B1-like (p < 0.001) and cytochrome P450 3A30-like (p < 0.05) via the nuclear xenobiotic receptors pathway was a key factor contributing to the disruption of tryptophan metabolism and steroid hormone biosynthesis, as well as inducing circadian rhythm disruption. Moreover, circadian rhythm disruption further exacerbated the imbalance of cytochrome P450 (CYP450) enzyme system as well as linoleic acid, arachidonic acid, sphingolipid, and glycerophospholipid metabolism. Overall, the feedback regulation between the CYP450 enzyme system and circadian rhythms emerged as the primary mechanism underlying DEHP-induced metabolic and transcriptional disruptions, ultimately resulting in gill toxicity. This study not only enriched the toxic effects on aquatic organisms of chronic exposure to DEHP, but provided potential biomarkers for the environmental risk assessment of DEHP.

Combined effects and potential mechanisms of phthalate metabolites on serum sex hormones among reproductive-aged women: An integrated epidemiology and computational toxicology study

The reproductive age is a crucial stage for women to bear offspring. However, reproductive-aged women are simultaneously exposed to various phthalates, which may pose a threat to their reproductive health. This study employed generalized linear regression and weighted quantile sum (WQS) regression to explore the associations between monoesters of phthalates (MPAEs) and sex hormones in 913 reproductive-aged women in the National Health and Nutrition Examination Survey. Key risk factors driving hormone disruption were identified based on the weights of the WQS models. Interaction models were used to unravel the synergistic or antagonistic effects between MPAEs. The potential toxicological targets of MPAEs interfering with sex hormone-binding globulin (SHBG) levels were revealed based on prior knowledge and molecular docking of hepatocyte nuclear factor 4α (HNF4α). Compared with the first quartile, mono-benzyl phthalate (MBZP) in the second quartile exhibited a decrease in total testosterone (TT) and TT/E2 (estradiol) ratio. Mono-2-ethyl-5-carboxypentyl phthalate (MECPP) in the fourth quartile showed a decrease in SHBG and TT/E2. Additionally, mono-(carboxyoctyl) phthalate and mono-(carboxynonyl) phthalate (MCNP) were negatively associated with SHBG. Each unit increase in the WQS index of MPAE mixtures was associated with 6.73 % lower SHBG levels (95 %CI: -12.80 %, -0.24 %) with mono-(3-carboxypropyl) phthalate, MCNP, MBZP, and MECPP identified as major risk factors. Interaction analyses revealed that the effects of high-risk MPAEs on SHBG were predominantly antagonistic. Molecular docking suggested that MPAEs might compete to bind tryptophan residues of HNF4α. This study provides key information to help develop the most effective phthalate interventions and improve the reproductive health of reproductive-aged women.

Sodium butyrate alleviates T-2 toxin-induced liver toxicity and renal toxicity in quails by modulating oxidative stress-related Nrf2 signaling pathway, inflammation, and CYP450 enzyme system

T-2 toxin is a member of class A aspergilloides toxins, one of the most prevalent mycotoxins that contaminate feed and food. Direct ingestion of animals or feed contaminated by T-2 toxin can cause various animal diseases. Butyrate is an organic fatty acid featuring a four-carbon chain, which is commonly found in the form of sodium butyrate (NaB). NaB has several biological functions and pharmacological effects. However, the role of sodium butyrate in alleviating T-2 toxin-induced hepatorenal toxicity has not been explored. In this study, 240 juvenile quails were evenly assigned into 4 groups. The experimental setup comprised four groups: The control group received a standard diet; the toxin group received a diet containing 0.9 mg/kg T-2 toxin; the butyrate group received a diet containing 0.5 g/kg NaB; and the T-2 treatment group received a diet containing both 0.9 mg/kg T-2 toxin and 0.5 g/kg NaB. We evaluated the histopathological changes in the kidney and liver on Days 14 and 28 and explored the molecular mechanisms involving oxidative stress, inflammation, and expression of nuclear xenobiotic receptors (NXRs). Our results showed that T-2 toxin exposure-induced inflammation in the liver and kidney by activating the oxidative stress pathway and modulating expression of NXRs to regulate related CYP450 isoforms, ultimately leading to histopathological injury in the liver and kidney, whereas sodium butyrate ameliorated this injury. These results offer novel insights into the molecular mechanisms underlying the protective effects of sodium butyrate in mitigating T-2 toxin-induced hepatorenal injury in juvenile quails. PRACTICAL APPLICATION: The mechanisms of T-2 toxin toxicity have been well described in experimental animals, but studies in birds are limited. With the development of society, the market scale of quails farming has been expanding, and the value of quails meat and eggs is increasing; there is an urgent need to clarify the harm of T-2 toxin to quails and its mechanism.

Relationship between phthalate exposure and kidney function in Taiwanese adults as determined through covariate-adjusted standardization and cumulative risk assessment

Few studies have investigated the associations between phthalate exposure and kidney function indicators in adults by simultaneously performing covariate-adjusted creatinine standardization, cumulative risk assessment, and mixture analysis. Thus, we applied these methods simultaneously to investigate the aforementioned associations in an adult population. This cross-sectional study analyzed data (N = 839) from a community-based arm of the Taiwan Biobank. The levels of 10 urinary phthalate metabolites were measured and calculated as the sum of the molar concentrations of the dibutyl phthalate metabolite (ΣDBPm) and di(2-ethylhexyl) phthalate (DEHP) metabolite (ΣDEHPm). The hazard index (HI) and daily intake (DI) were estimated by measuring the urinary levels of the phthalate metabolite. Kidney function biomarkers were assessed by measuring the following: blood urea nitrogen (BUN), uric acid, the albumin-to-creatinine ratio (ACR), and the estimated glomerular filtration rate (eGFR). Generalized linear models were implemented to examine the associations between exposure to individual phthalates, HI scores, and kidney function biomarkers. We also employed Bayesian kernel machine regression (BKMR) to analyze the relationships between exposure to various combinations of phthalates and kidney function. ΣDEHPm levels were significantly and positively associated with BUN and ACR levels, and ΣDBPm levels were positively associated with ACR levels. In addition, eGFR was negatively associated with ΣDBPm and ΣDEHPm levels. In the BKMR model, a mixture of 10 phthalate metabolites was significantly associated with BUN, uric acid, ACR, and eGFR results. Higher DIDEHP and higher DIDnBP values were significantly associated with lower eGFRs and higher ACRs, respectively. Higher DIDiBP and DIDEP values were significantly associated with higher uric acid levels. A higher HI was significantly associated with lower eGFRs and higher ACRs. Our results suggest that exposure to environmental phthalates is associated with impaired kidney function in Taiwanese adults.

Fumonisin B1 induces endoplasmic reticulum damage and inflammation by activating the NXR response and disrupting the normal CYP450 system, leading to liver damage in juvenile quail

Fumonisin B1 (FB1) is a mycotoxin affecting animal health through the food chain and has been closely associated with several diseases such as pulmonary edema in pigs and diarrhea in poultry. FB1 is mainly metabolized in the liver. Although a few studies have shown that FB1 causes liver damage, the molecular mechanism of liver damage is unclear. This study aimed to evaluate the role of liver damage, nuclear xenobiotic receptor (NXR) response and cytochrome P450 (CYP450)-mediated defense response during FB1 exposure. A total of 120 young quails were equally divided into two groups (control and FB1 groups). The quails in the control group were fed on a normal diet, while those in the FB1 group were fed on a quail diet containing 30 mg/kg for 42 days. Histopathological and ultrastructural changes in the liver, biochemical parameters, inflammatory factors, endoplasmic reticulum (ER) factors, NXR response and CYP450 cluster system and other related genes were examined at 14 days, 28 days and 42 days. The results showed that FB1 exposure impaired the metabolic function and caused liver injury. FB1 caused ER stress and decreased adenosine triphosphatease activity, induced the expression of inflammation-related genes such as interleukin 6 and nuclear factor kappa-B, and promoted inflammation. In addition, FB1 disrupted the expression of multiple CYP450 isoforms by activating nuclear xenobiotic receptors (NXRs). The present study confirms that FB1 exposure disturbs the homeostasis of cytochrome P450 systems (CYP450s) in quail liver by activating NXR responses and thereby causing liver damage. This study's findings provide insight into the molecular mechanisms of FB1-induced hepatotoxicity.

Toxicity assessment of di(2-ethylhexyl) phthalate using zebrafish embryos: Cardiotoxic potential

Plasticizers are considered as newly emerged contaminants. They are added to plastics to increase their flexibility and softness. Phthalate plasticizers including the Di-2-ethylhexyl phthalates (DEHP) are toxic and induce adverse effects on the different organization levels of the environment. In the current study, we investigated the potential toxicity of DEHP using Zebrafish as a biological model. Five ascending concentrations of DEHP were tested in embryos throughout 96 hpf: 0.0086, 0.086, 0.86, 8.6, and 86 mg/L. Embryotoxicity assessments revealed limited lethal effects on DEHP-exposed embryos, yet notable anticipation of the hatching process was observed at 48 hpf. Although DEHP showed negligible influence on the length and pericardial area of exposed embryos, it led to multiple bodily deformities. Gene expression analyses of key cardiogenic and inflammatory genes evidenced alterations in tbx20, bcl2, and il1b expression in Zebrafish embryos at 96 h post-fertilization. Results from the cardiac function analysis displayed that DEHP significantly affected the arterial pulse and linear velocity within the Posterior Cardinal Vein (PCV) of exposed fish. These findings strongly advance that even at low concentrations, DEHP can be considered as potential toxic agent, capable of inducing cardiotoxic effects.

Environmental toxicants and nephrotoxicity: Implications on mechanisms and therapeutic strategies

Kidneys are one of the most important organs in the human body. In addition to filtering 200 liters of fluid every 24 hours, the kidney also regulates acid-base balance, maintains electrolyte balance, and removes waste and toxicants from the body. Nephrotoxicity is the term used to describe the deterioration of kidney function caused by the harmful effects of medications and various types of environmental toxicants. Exposure to environmental toxicants is an inevitable side effect in the world's increasing industrialization and even more prevalent in underdeveloped nations. Growing data over the past few years has illuminated the probable connection between environmental toxicants and nephrotoxicity. Phthalates, microplastics, acrylamide and bisphenol A are environmental toxicants of particular concern, which are known to have nephrotoxic effects. Such toxicants may accumulate in the kidneys of humans after being consumed, inhaled, or come into contact with the skin. They can enter cells through endocytosis and accumulate in the cytoplasm. Small-sized nephrotoxicants can cause a variety of ailments including inflammation with increased production of pro-inflammatory cytokines, oxidative stress, mitochondrial dysfunction, autophagy, and apoptosis. This study uncovers the potential for new insights concerning the relationship between various environmental toxicants and kidney health. The objectives of this review is to establish information gaps, assess and identify the toxicity mechanisms of different nephrotoxicants, identify innovative pharmacological therapies that demonstrate promising therapeutic benefits/ relevance, and discuss the predictions for the future based on the analysis of the literature.

Effect of atrazine on testicular toxicity involves accommodative disorder of xenobiotic metabolizing enzymes system and testosterone synthesis in European quail (Coturnix coturnix)

Due to the wide use of atrazine (ATR), the concern has increased regarding the negative impact of ATR on reproduction. Nevertheless, the reproductive effects caused by different exposure concentrations and the severity of toxic damage are poorly understood. In organisms, ATR is metabolized and degraded through phase II enzyme systems, and changes in cytochrome P450 (CYP) enzymes may have a regulatory role in the harm of ATR. However, less information is available on the induction of CYPs by ATR in avian organisms, and even less on its effects on the testis. Birds are exposed to ATR mainly through food residues and contaminated water, the purpose of this study was to examine reproductive toxicity by different exposure concentrations and elaborate metabolic disorders caused by ATR in European quail (Coturnix coturnix). In this study, the quail were given ATR at 50 mg/kg, 250 mg/kg and 500 mg/kg by oral gavage for 45 days, and the testicular weight coefficients, histopathology and ultrastructure of testes, primary biochemical functions, sex steroid hormones, critical protein levels in the testosterone synthesis pathway, the expression of genes involved CYPs, gonad axis and nuclear receptors expression were investigated. Altogether, testicular coefficient decreased significantly in the high-dose group (1.22%) compared with the control group (3.03%) after 45 days of ATR exposure, and ATR is a potent CYP disruptor that acts through the NXRs and steroid receptor subfamily (APND, CAR, ERND and ERα) without a dose-dependent manner. Notably, ATR interfered with the homeostasis of hormones by triggering the expression of hormones on the gonad axis (LH and E2). These results suggest that exposure to ATR can cause testicular toxicity involving accommodative disorder of phase II enzyme and testosterone synthesis in European quail.

Di-(2-ethylhexyl) phthalate impairs angiogenesis and hematopoiesis via suppressing VEGF signaling in zebrafish

Di-(2-ethylhexyl) phthalate (DEHP) is among the most widely used plasticizers in plastic production, which has been detected in various environments. However, DEHP safety remains poorly known. Using zebrafish models, the effects of DEHP on the angiogenesis and hematopoiesis, and the underlying mechanism, were studied. Transgenic zebrafish embryos with specific fluorescence of vascular endothelial cells, myeloid cells, or hematopoietic stem cells were exposed to 0, 100, 150, 200, or 250 nM of DEHP for 22, 46 or 70 h, followed by fluorescence observation, endogenous alkaline phosphatase activity measurement, erythrocyte staining, and gene expression analysis by quantitative PCR and whole mount in situ hybridization. High DEHP concentrations decreased the sprouting rate, average diameter, and length, and the expansion area of the vessels lowered the EAP activity and suppressed the vascular endothelial growth factor (vegf) and hematopoietic marker genes, including c-myb, hbae1, hbbe1, and lyz expressions. DEHP treatment also decreased the number of hematopoietic stem cells, erythrocytes, and myeloid cells at 24 and 72 hpf. These DEHP-induced angiogenetic and hematopoietic defects might be alleviated by vegf overexpression. Our results reveal a plausible mechanistic link between DEHP exposure-induced embryonic angiogenetic defect and hematopoietic impairment.

Novel Role of Hemeoxygenase-1 in Phthalate-Induced Renal Proximal Tubule Cell Ferroptosis

Phthalates are widely used to improve the flexibility of poly(vinyl chloride) (PVC) polymer agriculture products. Di(2-ethylhexyl) phthalate (DEHP) is a type of addition to plastic and can lead to many health problems. Hemeoxygenase-1 (HO-1) is an extremely important molecule that releases enzymatic products to promote ferroptosis. This research aimed to explore the function of HO-1 in DEHP-induced renal proximal tubule cell ferroptosis. In the experiment, ICR male mice are exposed to (0, 50, 200, and 500 mg/kg BW/day) DEHP for 28 days. Here, we observed that DEHP induced glomeruli atrophy and the tubules swell. Furthermore, DEHP exposure could increase ferrous iron content and decrease antioxidant activity. We also found that DEHP exposure increased the expression of nuclear factor-erythroid 2 p45-related factor 2 (NFE2L2) in the nucleus. In particular, the expression of (HO-1) is significantly increased both in protein and mRNA levels. Glutathione peroxidase 4 (GPX4) as an endogenous control of ferroptosis was downregulated, which proved the occurrence of ferroptosis. In the study, exposure to DEHP activated the NFE2L2/HO-1 signaling pathway and resulted in ferroptosis of the proximal tubule. This research connects ferroptosis with HO-1, providing new insights into the potential roles of phthalates in nephrotoxicity.

Dimethyl Fumarate Attenuates Di-(2-Ethylhexyl) Phthalate-Induced Nephrotoxicity Through the Nrf2/HO-1 and NF-κB Signaling Pathways

This study aimed to clarify the nephroprotective effect of dimethyl fumarate (DMF) against Di (2-ethylhexyl) phthalate (DEHP)-induced nephrotoxicity in both in vitro and in vivo models. The HEK-293 cells were exposed to different concentrations of DMF plus IC50 concentration of monoethylhexyl phthalate (MEHP) (the main metabolite of DEHP). Then, some of the oxidative stress parameters including ROS, MDA, and GSH, and cytotoxicity (MTT assay) were determined in treated cells. For in vivo evaluation, rats were divided into 7 groups (n = 6 per group). Corn oil group (gavage), DEHP group (200 mg/kg dissolved in corn oil, gavage), DMF (15, 30, and 60 mg/kg, gavage) plus DEHP (200 mg/kg) groups, DMF (60 mg/kg, gavage) alone, and vitamin E (20 mg/kg, intraperitoneal (IP)) plus DEHP (200 mg/kg) group. This treatment continued for 45 days. Then, BUN and creatinine were evaluated by a commercial kit based on the urease enzymatic method and the Jaffe method, respectively. Mitochondrial oxidative stress and mitochondrial dysfunction parameters were evaluated using appropriate reagents, and gene expression of the p65 nuclear factor kappa B (NF-κB), tumor necrosis factor alpha (TNFα), nuclear factor E2-related factor 2 (Nrf2), and heme oxygenase-1 (HO-1) were evaluated by real-time PCR method. High concentrations of DMF significantly increased cell viability, and GSH content and significantly decreased ROS and MDA levels compared with the MEHP group in HEK-293 cells. DMF (60 mg/kg) significantly decreased BUN and creatinine levels compared with the DEHP group. Mitochondrial function and mitochondrial swelling were significantly improved in DMF group (60 mg/kg) compared with the DEHP group. DMF (30 and 60 mg/kg) significantly improved MMP collapse compared with the DEHP group. DMF (30 and 60 mg/kg) significantly decreased ROS levels compared with the DEHP group in isolated kidney mitochondria. DMF (60 mg/kg) significantly decreased MDA levels and significantly increased GSH content compared with DEHP group in isolated kidney mitochondria. The mRNA expression levels of Nrf2 and HO-1 were significantly reduced in the DEHP group compared to the control group and were significantly increased in the DMF group compared to the DEHP group. p65NF-κB and TNFα mRNA expression levels were significantly increased in the DEHP group compared to the control group. However, DMF significantly decreased p65NF-κB and TNFα mRNA expression compared to the DEHP group. DMF can act as a nephroprotective agent against DEHP partly through modulation of oxidative stress, mitochondrial function, and inflammation.

Exposure to di (2-ethylhexyl) phthalate causes locomotor increase and anxiety-like behavior via induction of oxidative stress in brain

Di (2-ethylhexyl) phthalate (DEHP) is one of the most prevalent xenoestrogen endocrine disruptor in daily life. A growing number of studies showed that DEHP could exhibit long-term adverse health effects on the human body, particularly in the liver, kidneys, heart and reproductive systems. However, the impact of oral intake of DEHP on the nervous system is extremely limited. In the present study, the adult C57BL/6J male mice were intragastrically administered with two dosages of DEHP for 35 days. The behavioral parameters were assessed using the elevated plus maze and open-field test. The mRNA expression levels of neuropeptides and the oxidative stress-associated proteins were detected by qPCR and western blot seperately. The histopathologic alterations of the brain were observed by H&E and Nissl staining. The results demonstrated that DEHP exposure could result in neurobehavioral impairments such as locomotor increase and anxiety-like behavior. Furthermore, pathological damages were clearly observed in the cerebral cortex and hippocampus, accompanied by a decrease in neuropeptides and an increase in oxidative stress, which were all positively correlated with the dose of DEHP. Together, these findings provide valuable clues into the DEHP-induced neurotoxicity.

Bromoacetic acid causes oxidative stress and uric acid metabolism dysfunction via disturbing mitochondrial function and Nrf2 pathway in chicken kidney

Since the outbreak of COVID-19, widespread utilization of disinfectants has led to a tremendous increase in the generation of disinfection byproducts worldwide. Bromoacetic acid (BAA), one of the common disinfection byproducts in the environment, has triggered public concern because of its adverse effects on urinary system in mammals. Nevertheless, the BAA-induced nephrotoxicity and potential mechanism in birds still remains obscure. According to the detected content in the Taihu Lake Basin, the model of BAA exposure in chicken was established at doses of 0, 3, 300, 3000 μg/L for 4 weeks. Our results indicated that BAA exposure caused kidney swelling and structural disarrangement. BAA led to disorder in renal function (CRE, BUN, UA) and increased apoptosis (Bax, Bcl-2, caspase3). BAA suppressed the expression of mitochondrial biogenesis genes (PGC-1α, Nrf1, TFAM) and OXPHOS complex I genes (ND1, ND2, ND3, ND4, ND4L, ND5, ND6). Subsequently, BAA destroyed the expression of Nrf2 antioxidant reaction genes (Nrf2, Keap1, HO-1, NQO1, GCLM, GCLC). Furthermore, renal oxidative damage led to disorder in uric acid metabolism genes (Mrp2, Mrp4, Bcrp, OAT1, OAT2, OAT3) and exacerbated destruction in renal function. Overall, our study provided insights into the potential mechanism of BAA-induced nephrotoxicity, which were important for the clinical monitoring and prevention of BAA.

The gut microbiota metabolite glycochenodeoxycholate activates TFR-ACSL4-mediated ferroptosis to promote the development of environmental toxin-linked MAFLD

Metabolic dysfunction-associated fatty liver disease (MAFLD) has become the most common chronic liver disorders in the world, and yet has no approved pharmacotherapy due to the etiology is complex. In the last ten years, increasing evidence have identified the environmental pollutants as risk factors for MAFLD. However, the underlying mechanism remains unclear. Our study found that bromoacetic acid (BAA, a typical kind of environmental toxin) increased triglycerides and total cholesterol levels as well as induced obvious hepatic steatosis and inflammation. The lipidomics showed that ferroptosis was implicated in the environmental toxin-linked MAFLD. Besides, the analysis of microbial metabolomics showed significant change of gut microbiome in BAA groups and the content of gut microbiota metabolite (glycochenodeoxycholate, GCDCA) increased sharply. In vitro study, we observed features of ferroptotic cells by transmission electron microscopy after BAA/GCDCA treatment. Besides, we demonstrated that BAA/GCDCA significantly increased iron contents, with upregulating transferrin receptor (TFR) and acyl-CoA synthetase long-chain family 4 (ACSL4) expression levels. By contrast, iron chelator or silencing TFR relieved BAA/GCDCA-induced lipid metabolism disorder and inflammation. What's more, the interaction between TFR and ACSL4 was also identified. Taken together, we found that, in response to environmental toxin, gut microbiota metabolite GCDCA activates TFR-ACSL4-mediated ferroptosis, which triggered subsequent lipid metabolism disorder and inflammation. Moreover, these findings firstly highlighted the functional relevance among ferroptosis, lipid metabolism and gut microbiota metabolite during environmental pollutant exposure, which shed light on the deep mechanism of environmental toxin-related MAFLD, providing potential targets for the prevention of MAFLD.

DEHP triggers a damage severity grade increase in the jejunum in quail (Coturnix japonica) by disturbing nuclear xenobiotic receptors and the Nrf2-mediated defense response

As a plasticizer, di-2-ethylhexyl phthalate (DEHP) has been listed as a potential endocrine disruptor by The World Health Organization. The toxicity of DEHP has been widely studied, but its toxicity on the digestive tract of birds has not been clarified. Female quail were treated by gavage with DEHP (250, 500, 750 mg/kg), with the blank and vehicle control groups reserved. The result showed that DEHP raised the damage severity grade, and decreased the ratio of villus length to crypt depth. The content and activity of cytochrome P450 system (CYP450s) were increased by DEHP. DEHP interfered with the transcription of nuclear xenobiotic receptors (NXRs), CYP isoforms, and the nuclear factor-E2-related factor 2 (Nrf2) signaling pathway. This study revealed DEHP could cause the imbalance in CYP450s mediated by NXRs, and then promote Nrf2 mediated antioxidant defense. This study provided new evidence about the mechanisms of DEHP-induced toxic effects on digestive tract.

Multi-omics profiling and biochemical assays reveal the acute toxicity of environmental related concentrations of Di-(2-ethylhexyl) phthalate (DEHP) on the gill of crucian carp (Carassius auratus)

Di-(2-ethylhexyl) phthalate (DEHP) is one of the most extensively utilized plasticizers in the plastic manufacturing process. It is widely used in various fields due to its low cost and excellent effect. Although there is evidence that DEHP is harmful to animal and human health, DEHP-induced gill toxicity in aquatic organisms is inconclusive, and its mechanism has not been fully elucidated. Here, we investigated the effects of DEHP acute exposure on crucian carp gills at environmentally relevant concentrations of 20, 100, and 500 μg/L. Multi-omics profiling and biochemical assays were employed to characterize the potential toxicological mechanisms. The results showed that acute exposure to 100 and 500 μg/L of DEHP leads to oxidative stress in gills, as evidenced by overproduction of reactive oxygen species (ROS), increased antioxidant enzyme activity, and the transformation of glutathione from reduced to oxidized form, resulting in lipid peroxidation. Integrative analysis of transcriptomics and metabolomics indicated that increased purine metabolism was the potential source of increased ROS. Moreover, lipid metabolism disorder, including arachidonic acid metabolism, induces inflammation. Further, DEHP causes the imbalance of the CYP enzyme system in the gill, and DEHP-induced gill toxicity in crucian carp was associated with interference with CYP450 homeostasis. Taken together, this study broadens the molecular understanding of the DEHP-induced gill toxicity in aquatic organisms and provides novel perspectives for assessing the effects of DEHP on target and non-target aquatic organisms in the environment.

Lag associations of gestational phthalate exposure with maternal serum vitamin D levels: Repeated measure analysis

Few studies have investigated the relationships between gestational phthalate exposure and maternal circulating vitamin D. In the Ma'anshan birth cohort, 3265 pregnant women were included. Each woman provided up to three urine and serum samples for measurement of phthalates and 25(OH)D and calcium, respectively. Linear mixed models were performed to analyse the association between phthalate metabolites and 25(OH)D and calcium. Stratified analyses of the relationship between phthalates and 25(OH)D by urine collection season were conducted. Finally, the post hoc lag effect of phthalate exposure on 25(OH)D was determined if longitudinal associations were significant. Some phthalate metabolites were associated with increased 25(OH)D but with decreased calcium. Furthermore, the relationship of phthalate exposure with 25(OH)D varied with urine collection season. Phthalate metabolites collected in summer and autumn were associated with an increase in 25(OH)D, while monobenzyl phthalate collected in winter and spring was inversely associated with 25(OH)D. Finally, high-molecular-weight phthalates had lag associations with 25(OH)D with a 1-trimester lag period. Low-molecular-weight phthalates exhibited lag associations with 25(OH)D with a 2-trimester lag period. In conclusion, the positive cross-sectional correlation between phthalate metabolites and 25(OH)D was partly affected by urine collection season. This study suggested that gestational phthalate exposure would have a lag association with maternal 25(OH)D levels.

The novel role of the aquaporin water channel in lycopene preventing DEHP-induced renal ionic homeostasis disturbance in mice

Di-(2-ethylhexyl) phthalate (DEHP), an extensively used plasticizer, can cause environmental pollution and organ injury. Lycopene (LYC) is a natural carotene that has the potential to prevent chronic diseases. To reveal the effect of DEHP and/or LYC on the kidney, male mice were treated with LYC (5 mg/kg) and/or DEHP (500 mg/kg or 1000 mg/kg) by gavage for 28 days. The study indicated that DEHP caused glomerular atrophy, tubular expansion, disappearance of the mitochondrial membrane, and cristae rupture. DEHP exposure can increase the expression of aquaporin (AQP) subunits and the activity of Ca²⁺-Mg²⁺-ATPase and decrease the activity of Na⁺-K⁺-ATPase, which results in ion disorder. However, LYC can relieve kidney injury by regulating the activity of ATPase, the expression of ATPase subunits, and AQP subunit expression. The results indicated that AQP was a target for LYC in antagonizing the disturbance of DEHP-induced renal damage.

Lycopene prevents DEHP-induced testicular endoplasmic reticulum stress via regulating nuclear xenobiotic receptors and unfolded protein response in mice

Lycopene (LYC) is a potent antioxidant synthesized by red vegetables or plants. Di-2-ethylhexyl phthalate (DEHP) is frequently detected in diverse agricultural environments and considered as a reproductive toxicant. The present research was designed to assess the potential mechanisms of DEHP-induced testicular toxicity and the treatment efficacy of LYC. In this study, after the oral administration of LYC at the dose of 5 mg per kg b.w. per day, mice were given 500 or 1000 mg per kg b.w. per day of DEHP. This research suggested that LYC prevented the DEHP-induced disorder at the levels of activity and content of CYP450 enzymes. LYC attenuated DEHP-caused enhancement in nuclear xenobiotic receptors (NXRs) and the phase I metabolizing enzymes (CYP1, CYP2, CYP3, etc.) levels. Furthermore, endoplasmic reticulum (ER) stress was induced by DEHP and triggered unfolded protein response (UPR). Interestingly, LYC could effectively ameliorate these "hit". The present study suggested that LYC prevents DEHP-induced ER stress in testis via regulating NXRs and UPRER.

Lycopene Preventing DEHP-Induced Renal Cell Damage Is Targeted by Aryl Hydrocarbon Receptor

Di (2-ethylhexyl) phthalate (DEHP) is an environmentally persistent and bioaccumulative plasticizer. Accumulation of DEHP in the body can eventually cause kidney damage. As a type of natural carotenoid, lycopene (LYC) has a potential protective effect on renal cells, but the protective mechanism has not yet been elucidated. The major goal of this study was to see how effective LYC was at treating DEHP-induced nephrotoxicity in mice. ICR mice were treated with DEHP (500 mg/kg BW/day or 1000 mg/kg BW/day) or LYC (5 mg/kg BW/day) for 28 days. Through histopathology and ultrastructure, we found that LYC attenuated DEHP-induced renal tubular cell and glomerular damage. LYC relieved DEHP-induced kidney injury evidenced by lower levels of blood urea nitrogen (Bun), creatinine (Cre), and uric acid (Uric). Meanwhile, the reduced expression of kidney injury molecule-1 (Kim-1) also supported it. Notably, LYC can alleviate the activity or content of cytochrome P450 system (CYP450s) interfered with by DEHP. In addition, LYC treatment reduced nuclear accumulation of DEHP-induced aromatic hydrocarbon receptor (AhR) and AhR nuclear transporter (Arnt), and its downstream target genes such as cytochrome P450-dependent monooxygenase (CYP) 1A1, 1A2, and 1B1 expression significantly decreased to normal in the LYC treatment group. In summary, LYC can mediate the AhR/Arnt signaling system to prevent kidney toxicity in mice caused by DEHP exposure.

Exposure to phthalates and environmental phenols in association with chronic kidney disease (CKD) among the general US population participating in multi-cycle NHANES (2005-2016)

Exposure to consumer chemicals has been associated with chronic kidney disease (CKD) among humans, but their associations with estimated glomerular filtration rate (eGFR) are inconsistent. Such observations may be due to potential bias caused by the method of urine dilution adjustment and lack of consideration for multiple chemical exposure in the association models. This study aimed to identify major urinary chemicals associated with CKD by applying an alternative adjustment method of urine dilution ('novel' covariate-adjusted creatinine adjustment vs 'traditional' creatinine adjustment) and with a mixture exposure concept in the association model. For this purpose, the adult participants of US National Health and Nutrition Examination Survey (NHANES) 2005-2016 (n = 9008) were used, and the associations of urinary exposure biomarkers of major consumer chemicals, e.g., phthalates, bisphenol A, benzophenone-3, and parabens, with CKD related parameters of eGFR and albumin-to-creatinine ratio (ACR), were assessed. The use of the novel covariate-adjusted creatinine standardization resulted in significant inverse associations with eGFR for most measured chemicals, unlike the results with the use of the conventional creatinine adjustment. Phthalate metabolites, such as monobutyl phthalate (MBP) and mono-benzyl phthalate (MBzP), were positively associated with ACR. Even in mixture exposure models using weighted quantile sum (WQS) regression, MBzP, metabolites of di-(2-ethylhexyl) phthalate (DEHP), and bisphenol A (BPA) were revealed as major drivers of the association with eGFR or ACR. Results of sensitivity analyses with the subpopulation with normal eGFR range (n = 7041) were generally similar. Our observation suggests that exposure to benzyl butyl phthalate (BBP), DEHP, and BPA may be responsible for declined eGFR and increased ACR even at the exposure levels occurring among general adults.

Lycopene prevents DEHP-induced hepatic oxidative stress damage by crosstalk between AHR-Nrf2 pathway

Di (2-ethylhexyl) phthalate (DEHP) is a widespread plasticizer that persists in the environment and can significantly contribute to serious health hazards of liver especially oxidative stress injury. Lycopene (LYC) as a carotenoid has recently gained widespread attention because of antioxidant activity. However, the potential mechanism of DEHP-induced hepatotoxicity and antagonism effect of LYC on it are still unclear. To explore the underlying mechanisms of this hypothesis, the mice were given by gavage with LYC (5 mg/kg) and DEHP (500 or 1000 mg/kg). The data suggested that DEHP caused liver enlargement, reduction of antioxidant activity markers, increase of oxidative stress indicators and disorder of cytochrome P450 enzymes system (CYP450s) homeostasis. DEHP-induced reactive oxygen species (ROS) activated the NF-E2-relatedfactor2 (Nrf2) and nuclear xenobiotic receptors (NXRs) system including Aryl hydrocarbon receptor (AHR), Pregnane X receptor (PXR) and Constitutive androstane receptor (CAR). Interestingly, these disorders and injuries were prevented after LYC treatment. Taken together, DEHP administration resulted in hepatotoxicity including oxidative stress injury and disordered CYP450 system, but these alterations might be ameliorated by LYC via crosstalk between AHR-Nrf2 pathway.

Mechanistic insight into toxicity of phthalates, the involved receptors, and the role of Nrf2, NF-κB, and PI3K/AKT signaling pathways

The wide use of phthalates, as phthalates are used in the manufacturing of not only plastics but also many others goods, has become a main concern in the current century because of their potency to induce deleterious effects on organism health. The toxic effects of phthalates such as reproductive toxicity, cardiotoxicity, hepatotoxicity, nephrotoxicity, teratogenicity, and tumor development have been widely indicated by previous experimental studies. Some of the important mechanisms of toxicity by phthalates are the induction and promotion of inflammation, oxidative stress, and apoptosis. Awareness of the involved molecular pathways of these mechanisms will permit the detection of exact molecular targets of phthalates to protect or treat their toxicity. Up to now, various transcription factors and signaling pathways have been associated with phthalate-induced toxicity which by influencing on nuclear surface and the expression of different genes can alter cell hemostasis. In different studies, the role of nuclear factor erythroid 2-related factor 2 (Nrf2), nuclear factor-κB (NF-κB), and phosphatidylinositol-3-kinase (PI3K)/AKT signaling pathways in processes of oxidative stress, inflammation, apoptosis, and cancer has been shown following exposure to phthalates. In the present review, we aim to survey experimental studies (in vitro and in vivo) in order to show firstly the most involved receptors and also the importance and the role of the mentioned signaling pathways in phthalate-induced toxicity, and with considering this point, the future studies can focus on these molecular targets as a strategic method to reduce environmental chemicals-induced toxicity especially phthalates toxic effects.

Comparative study on protective effect of different selenium sources against cadmium-induced nephrotoxicity via regulating the transcriptions of selenoproteome

Cadmium (Cd) is a ubiquitous environmental pollutant, which mainly input to the aquatic environment through discharge of industrial and agricultural waste, can be a threat to human and animal health. Selenium (Se) possesses a beneficial role in protecting animals and ameliorating the toxic effects of Cd. However, the comparative antagonistic effects of different Se sources such as inorganic, organic Se and nano-form Se on Cd toxicity are still under-investigated. Hence, the purpose of this study was to evaluate the comparative of Se sources antagonism on Cd-induced nephrotoxicity via oxidative stress and selenoproteome transcription. In the present study, Cd-diet disturbed in the system balance of 5 trace elements (Zinc (Zn), copper (Cu), Iron (Fe), Se, Cd) and impaired renal function. Se sources, including nano- Se (NS), Se- yeast (SY), sodium selenite (SS) and mixed selenium (MS) significantly recovered the balance of 4 trace elements (Zn, Cu, Cd, Se) and renal impaired indexes (blood urea nitrogen (BUN) and creatinine (CREA)). Histological appearance of Cd-treated kidney indicated renal tubular epithelial vacuoles, particle degeneration and enlarged capsular space. Ultrastructure observation results illustrated that Cd-induced mitochondrial cristae reduction, membrane disappearance, and nuclear deformation. Treatment with Se sources, NS appeared a better impact on improving kidney tissues against the pathological alterations resulting from Cd administration. Meanwhile, NS reflected a significant impact on relieving Cd-induced kidney oxidative damage, and significantly restored the antioxidant defense system of the body. Our findings also showed NS ameliorated the Cd-induced downtrends expression of selenoproteome and selenoprotein synthesis related transcription factors. Overall, NS was the most effective Se source in avoiding of Cd cumulative toxicity, improving antioxidant capacity and regulating of selenoproteome transcriptome and selenoprotein synthesis related transcription factors expression, which contributes to ameliorate Cd-induced nephrotoxicity in chickens. These results demonstrated diet supplement with NS may prove to be an effective approach for alleviating Cd toxicity and minimizing Cd -induced health risk.

Multiple transcriptomic profiling: p53 signaling pathway is involved in DEHP-induced prepubertal testicular injury via promoting cell apoptosis and inhibiting cell proliferation of Leydig cells

Di(2-ethylhexyl) phthalate (DEHP) is a widely-used plasticizer and has long been recognized as an endocrine-disrupting chemical with male reproductive toxicities. DEHP exposure at the prepubertal stage may lead to extensive testicular injury. However, the underlying mechanisms remain to be elucidated. In the present study, we gavaged male C57BL/6 mice with different concentrations of DEHP (0, 250, and 500 mg/kg-bw·d) from postnatal day 22-35, and exposed TM3 Leydig cells with 0, 100, 200, 300, and 400 μM of MEHP (bioactive metabolite of DEHP) for 12-48 h. RNA sequencing was performed both in testicular tissue and TM3 cells. The results showed that DEHP disrupts testicular development and reduces serum testosterone levels in male prepubertal mice. Bioinformatic analysis and experimental verification have revealed that DEHP/MEHP induces cell cycle arrest in TM3 cells and increases apoptosis both in vivo and in vitro. Furthermore, the p53 signaling pathway was found to be activated upon DEHP/MEHP treatment. The inhibition of p53 by pifithrin-α significantly reduced MEHP-induced injuries in TM3 cells. Cumulatively, these findings revealed the involvement of the p53 signaling pathway in DEHP-induced prepubertal testicular injury by promoting cell apoptosis and inhibiting cell proliferation of Leydig cells.

Gene expression in rat placenta after exposure to di(2-ethylhexyl) phthalate

The organic compound di(2-ethylhexyl) phthalate (DEHP) is widely used as a plasticizer in many products. Exposure to DEHP has been reported to lead to adverse pregnancy outcomes by suppressing placenta growth and development. The aim of this study was to determine the gene expression profiles of rat placenta exposed to (DEHP) and identify genes crucial for the DEHP response. Three groups of Wistar rats were administered an intragastric dose of 1,000 mg/kg DEHP, 500 mg/kg DEHP, or corn oil, RNA was isolated from placenta tissue, and hybridization was performed. Gene expression profiles were analyzed by identifying functional enrichment, differentially expressed genes (DEGs), protein-protein interaction (PPI) networks and modules, and transcription factor (TF)-miRNA-target regulatory networks. We obtained 2,032 DEGs, including cytochrome P450, family 2, subfamily R, polypeptide 1 (CYP2R1), sterol O-acyltransferase 2 (SOAT2), and 24-dehydrocholesterol reductase (DHCR24) from the steroid biosynthesis pathway and somatostatin receptor 4 (SSTR4) and somatostatin receptor 2 (SSTR2) in the neuroactive ligand-receptor interaction pathway. The PPI network included 476 nodes, 2,682 interaction pairs, and three sub-network modules. Moreover, eight miRNAs, three TFs, and 176 regulatory pairs were obtained from the TF-miRNA-target regulatory network. CYP2R1, SOAT2, DHCR24, SSTR4, and SSTR2 may affect DEHP influence on rat placenta development.

Selenium mitigates cadmium-induced crosstalk between autophagy and endoplasmic reticulum stress via regulating calcium homeostasis in avian leghorn male hepatoma (LMH) cells

Cadmium (Cd) is a toxic heavy metal and widespread in environment and food, which is adverse to human and animal health. Food intervention is a hot topic because it has no side effects. Selenium (Se) is an essential trace element, found in various fruits and vegetables. Many previous papers have described that Se showed ameliorative effects against Cd. However, the underlying mechanism of antagonistic effect of Se against Cd-induced cytotoxicity in avian leghorn male hepatoma (LMH) cells is unknown, the molecular mechanism of Se antagonistic effect on Cd-induced and calcium (Ca²⁺) homeostasis disorder and crosstalk of ER stress and autophagy remain to be explored. In order to confirm the antagonistic effect of Se on Cd-induced LMH cell toxicity, LMH cells were treated with CdCl₂ (2.5 μM) and Na₂SeO₃ (1.25 and 2.5 μM) for 24 h. In this study, Cd exposure induced cell death, disrupted intracellular Ca²⁺ homeostasis and Ca²⁺ homeostasis related regulatory factors, interfered with the cycle of cadherin (CNX)/calreticulin (CRT), and triggered ER stress and autophagy. Se intervention inhibited Cd-induced LDH release and crosstalk of ER stress and autophagy via regulating intracellular Ca²⁺ homeostasis. Moreover, Se mitigated Cd-induced Intracellular Ca²⁺ overload by Ca²⁺/calmodulin (CaM)/calmodulin kinase IV (CaMK-IV) signaling pathway. Herein, CNX/CRT cycle played a critical role for the protective effect of Se on Cd-induced hepatotoxicity. Based on these findings, we demonstrated that the application of Se is beneficial for prevention and alleviation of Cd toxicity.