DEHP triggers cerebral mitochondrial dysfunction and oxidative stress in quail (Coturnix japonica) via modulating mitochondrial dynamics and biogenesis and activating Nrf2-mediated defense response.

Di-(2-ethylhexyl) phthalate (DEHP) in the environment and food chain may impact cerebrum development and neurobehavioral in humans and wildlife. However, it is unclear that DEHP exposure caused cerebral toxicity. This experiment used gavage to expose female quail to 0, 250, 500, and 1000 mg/kg BW/day for 45 days to assess the potential neurotoxicity of DEHP to the cerebrum. It can be observed that there will be obvious neurological abnormalities in the experiment. Cerebrum histological lesions can be observed with HE-staining. Detecting oxidative stress indices, Nrf2 pathway, and mitochondrial dynamics factor, by analyzing the results, these results were observed that DEHP exposure can cause damage to the cerebrum by causing oxidative stress and affecting the balance of mitochondrial dynamics. Nrf2-mediated defense is not activated by exposure to 250 mg/kg DEHP. Nrf2-mediated defense is activated but is not resistant to exposure to medium and high doses of DEHP (500 mg/kg; 1000 mg/kg). DEHP triggers cerebral mitochondrial dysfunction via modulating mitochondrial dynamics.

Modulation of heat-shock response is associated with Di (2-ethylhexyl) phthalate (DEHP)-induced cardiotoxicity in quail (Coturnix japonica).

Di(2-ethylhexyl) phthalate (DEHP) is an omnipresent environmental pollutant with endocrine disrupting properties. As a plasticizer, DEHP can be leach from the plastic to transfer the external environment and thus enters the animal food chain, causing serious damage to the animal organs. The heat-shock response (HSR) comprising heat-shock protein (HSPs) and heat-shock transcription factor (HSFs) plays a pivotal role in various toxic stress conditions. For the sake of investigating the effects of DEHP exposure on cardiac toxicity and the regulation of HSR, male quail were fed the diet with 0, 250, 500 and 750 mg/kg DEHP by gavage administration for 45 days. Histopathological changes including cardiomyocyte swelling and muscle fiber dilatation were observed in the hearts exposed to DEHP. During the DEHP treatment, the mRNA expression of HSP60 and HSP70 were universally reduced, while the expression of other HSPs (HSP10, HSP25, HSP27, HSP40, HSP47, HSP90, HSP110) had different degrees of growth. In addition, the levels of HSF1, HSF2, and HSF3 were significantly increased. Given the facts above, DEHP exposure induced the toxic effects of quail heart. DEHP exposure did great harm to HSR via affecting the synthesis of HSFs to mediate the transcription of the HSPs. Ultimately, this study provided new evidence that DEHP-induced cardiotoxicity in quail was related to activation of HSR and playing a protective role.

Di (2-ethyl hexyl) phthalate (DEHP)-induced kidney injury in quail (Coturnix japonica) via inhibiting HSF1/HSF3-dependent heat shock response.

Di (2-ethyl hexyl) phthalate (DEHP) as a plasticizer can leach away from the plastic and hence entrances into the animal food chain which caused serious hazard in organs of animals, but there are few studies on DEHP kidney toxicity. The heat-shock response (HSR) consisting of the HSPs and HSFs plays an important role in various toxicity stress conditions. To investigate the influence on kidney toxicity and the modulation of HSR during DEHP exposure, female quail were fed the diet with 0, 250, 500 and 750 mg/kg DEHP by gavage administration for 45 days. The shrinkages of glomeruli and dilation of kidney tubule epithelia cells were observed in the kidney of DEHP-exposed quail. DEHP treatment could significantly decrease the expressions of HSP25, HSP27, HSP47, HSP60, while the expressions of HSP10, HSP40, HSP70, HSP90, HSP110 were upregulated in the kidney. In addition, the expression levels of HSF1 and HSF3 were significantly increased under DEHP. This is the first study to demonstrate quail exposure to DEHP is in fact detrimental to bird kidney. Besides, DEHP could attack HSR by affecting the synthesis of HSFs to mediate the transcription of the HSPs resulting in kidney damage.

Crosstalk between unfolded protein response and Nrf2-mediated antioxidant defense in Di-(2-ethylhexyl) phthalate-induced renal injury in quail (Coturnix japonica).

The widely used Di-(2-ethylhexyl) phthalate (DEHP) has been reported to exhibit ubiquitous environmental and global health hazards. The bioaccumulation and environmental persistence of DEHP can cause serious health hazards in wildlife animals and human. However, DEHP-induced nephrotoxicity in bird is remained unknown. Thus, this study explored the related mechanism of DEHP nephrotoxicity in quail. For this purpose, quail were exposed with DEHP at doses of 0, 250, 500, and 1000 mg/kg body weight daily by gavage administration for 45 days. The results showed that DEHP exposure induced renal injury, oxidative stress, and endoplasmic reticulum (ER) degeneration. Low level DEHP (250 mg/kg) exposure inhibited Nrf2 signaling pathway and induced renal injury via oxidative stress and suppressed the unfolded protein response (UPR) signaling pathway and induced ER stress in the kidney. But surprisingly, high level DEHP (500 mg/kg and 1000 mg/kg) exposure activated Nrf2 and UPR signaling pathways and protected kidney, but they still couldn't resist the toxicity of DEHP. Our study demonstrated that DEHP-induced nephrotoxicity in quail was associated with activating Nrf2-mediated antioxidant defense response and UPR signaling pathway.

Di (2-ethylhexyl) phthalate (DEHP)-induced hepatotoxicity in quails (Coturnix japonica) via triggering nuclear xenobiotic receptors and modulating cytochrome P450 systems.

Di (2-ethylhexyl) phthalate (DEHP) is a widely distributed pollutant that is of great concern due to its negative health effects. However, whether DEHP exposure causes liver toxicity in birds remains unclear. To clarify the potential hepatotoxicity of DEHP, quails were exposed to 0, 250, 500 and 1000 mg/kg BW/day DEHP by gavage treatment for 45 days. The livers of DEHP-exposed quails showed histomorphological changes. DEHP exposure induced a significant increase in cytochrome P450 enzyme system (CYP450s) activity (including aniline-4-hydroxylase (AH), aminopyrine N-demethylase (APND), erythromycin N-demethylase (ERND) and NADPH-cytochrome C reductase (NCR)) and in the contents of total cytochrome P450 (CYP450) and cytochrome b5 (Cyt b5) in quail liver. DEHP exposure also influenced the expression of nuclear xenobiotic receptors (NXRs) and CYP450 isoforms in the liver. The results suggested that DEHP-induced hepatotoxicity in quail liver is associated with activation of the NXRs pathway responses and disruption of CYP450s homeostasis. This study will help to further elucidate DEHP exposure-induced liver toxicity in quails.

Atrazine-induced environmental nephrosis was mitigated by lycopene via modulating nuclear xenobiotic receptors-mediated response.

The burden and morbidity of environmental nephrosis is increasing globally. Atrazine (ATR) and degradation products in the environment are considered key determinants of nephrosis. However, the lack of highly effective treatments for environmental nephrosis creates an urgent need to better understand the preventive strategies and mechanisms. This study aimed to highlight the mechanism of ATR-induced environmental nephrosis and the chemoprotective potential of lycopene (LYC) against the renal injury and nephrosis. Male mice were treated with LYC (5 mg/kg) and/or ATR (50 mg/kg or 200 mg/kg) by gavage administration for 21 days. Histopathological changes and biochemical function, cytochrome P450 enzymes system (CYP450s), nuclear xenobiotic receptors (NXRs) response and the transcription of CYP isoforms (CYPs) were detected. ATR exposure caused the changes of the histopathological and biochemical function, activated the NXR response and disturbed the CYP450s homeostasis. Supplementary LYC significantly prevented ATR-induced nephrotoxicity and alleviated the alternation of histopathological and biochemical function via modulating the CYP450s homeostasis and the NXR response. The results demonstrated AHR, CAR, PXR, PPAR (α, γ), CYP1, CYP2, CYP3 and CYP4 superfamily play a vital role in LYC-ATR interaction. Our findings provide new evidence that ATR exposure can cause the environmental nephrosis via inducing the kidney injury. Supplementary LYC showed significant chemoprotective potential against ATR-induced renal injury and environmental nephrosis via regulating the NXR response and the CYP450s homeostasis.

A novel nuclear xenobiotic receptors (AhR/PXR/CAR)-mediated mechanism of DEHP-induced cerebellar toxicity in quails (Coturnix japonica) via disrupting CYP enzyme system homeostasis.

Di-(2-ethylhexyl)-phthalate (DEHP) is causing serious health hazard in wildlife animal and human through environment and food chain, including the effect of brain development and impacted neurobehavioral outcomes. However, DEHP exposure caused cerebellar toxicity in bird remains unclear. To evaluate DEHP-exerted potential neurotoxicity in cerebellum, male quails were exposed with 0, 250, 500 and 750 mg/kg BW/day DEHP by gavage treatment for 45 days. Neurobehavioral abnormality and cerebellar histopathological alternation were observed in DEHP-induced quails. DEHP exposure increased the contents of total Cytochrome P450s (CYPs) and Cytochrome b5 (Cyt b5) and the activities of NADPH-cytochrome c reductase (NCR) and aniline-4-hydeoxylase (AH) in quail cerebellum. The expression of nuclear xenobiotic receptors (NXRs) and the transcriptions of CYP enzyme isoforms were also influenced in cerebellum by DEHP exposure. These results suggested that DEHP exposure caused the toxic effects of quail cerebellum. DEHP exposure disrupted the cerebellar CYP enzyme system homeostasis via affecting the transcription of CYP enzyme isoforms. The cerebellar P450arom and CYP3A4 might be biomarkers in evaluating the neurotoxicity of DEHP in bird. Finally, this study provided new evidence that DEHP-induced toxic effect of quail cerebellum was associated with activating the NXRs responses and disrupting the CYP enzyme system homeostasis.

Activating nuclear xenobiotic receptors and triggering ER stress and hepatic cytochromes P450 systems in quails (Coturnix C. coturnix) during atrazine exposure.

Atrazine (ATR) is one of the most widely detected contaminant in the ecosystem. Nuclear xenobiotic receptors are activated by herbicides and induce the transcription of CYP450 isoforms involved in xenobiotic metabolism and transport. However, little is known about hepatic nuclear xenobiotic receptors in birds are responsible for ATR-induced hepatotoxicity via regulating the cytochrome P450 enzyme systems (CYP450s). The objective of this study was to investigate the mechanism of ATR hepatotoxicity in quails. For this purpose, male quails were dosed by oral gavage from sexual immaturity to maturity with 0, 50, 250, and 500 mg/kg/day ATR for 45 days. The results showed that ATR exposure caused the hepatotoxicity damage and endoplasmic reticulum (ER) degeneration. It suggested that ER is a target organelle of ATR toxicity in hepatocytes. ATR exposure disrupted the hepatic CYP450s homeostasis. This study also demonstrated that ATR triggered the CYP450 isoforms transcription via activating the hepatic CAR/PXR pathway. The present study provides new insights regarding the mechanism of the ATR-induced hepatotoxicity through activating nuclear xenobiotic receptors and triggering ER stress and hepatic CYP450s in quails.

Performance of a novel atrazine-induced cerebellar toxicity in quail (Coturnix C. coturnix): Activating PXR/CAR pathway responses and disrupting cytochrome P450 homeostasis.

Atrazine is well known to be a biologically hazardous substance with toxic effects, but atrazine-induced neurotoxicity remains unclear. The aim of this study was to investigate the mechanisms of atrazine-induced cerebellar toxicity. To determine atrazine-exerted potential neurotoxicity, quails were treated with 50, 250 and 500 mg/kg atrazine by gavage administration for 45 days. Notably, the changes of cytochrome P450 enzyme system (CYP450s) were observed in atrazine-exposed quails. The contents of cytochrome P450 (CYP450) and Cytochrome b5 (Cyt b5) and the activities of NADPH-cytochrome c reductase (NCR), aminopyrin N-demethylase (APND) and aniline-4-hydeoxylase (AH) were increased and erythromycin N-demethylase (ERND) was decreased in quail cerebellum. Nuclear xenobiotic receptors (NXRs) and the transcriptions of NXRs-related target molecules were influenced in cerebellum. Atrazine disrupted the CYP450s balance in quail cerebellum. These results suggested that atrazine-induced cerebellar toxicity in birds was associated with activating PXR/CAR pathway responses and disrupting cytochrome P450 homeostasis. This study provided novel evidences that atrazine exposure induced cerebellar toxicity.

A novel mechanism underlies atrazine toxicity in quails (Coturnix Coturnix coturnix): triggering ionic disorder via disruption of ATPases.

The widely used atrazine has been reported to exhibit extensive ecological hazards. Due to the biological accumulation, atrazine elicits widespread toxic effects on different organisms. However, true proof for the mechanism of atrazine-induced toxicity is lacking. To determine the potential mechanism by which atrazine exerted toxic effects, quails were treated with atrazine (0, 50, 250 and 500 mg/kg) by gavage administration for 45 days. Atrazine significantly increased the histological alterations and serum creatine kinase, lactate dehydrogenase and choline esterase levels. A marked disorder in ionic (Na+, K+, Ca2+ and Mg2+)contents and the decrease of ATPases (Na+-K+-ATPase, Ca2+-ATPase, Mg2+-ATPase and Ca2+-Mg2+-ATPase) activities were observed in the heart and liver of atrazine-exposed quails. Of note, it was also observed that atrazine suppressed the transcription of Na+, K+ transfer associated genes (Na+-K+-ATPase subunits) and Ca2+ transfer associated genes (Ca2+-ATPase subunits, solute carriers) in heart and liver. In conclusion, atrazine induced cardiac and hepatic damage via causing the ionic disorder, triggering the transcription of the ion transporters and leading the histopathological and functional alternations in the heart and liver of quails. This study demonstrated atrazine significantly induced the ionic disorder via decreasing the ATPases activities and disturbing the transcription of the ion transporters.

Lycopene protects against atrazine-induced hepatotoxicity through modifications of cytochrome P450 enzyme system in microsomes.

Atrazine (ATR) is primarily distributed in liver and hazardous to animal health. Cytochrome P450 enzyme system (CYP450s) is responsible for the biotransformation of toxic substances. Lycopene (LYC) prevents the herbicide-induced toxicity. However, it is unclear that LYC protects against ATR-induced hepatotoxicity via modifying CYP450s. To ascertain the chemoprevention of LYC on ATR-induced hepatotoxicity, male Kunming mice were treated with LYC (5mg/kg) and/or ATR (50mg/kg or 200mg/kg) by gavage administration for 21 days. These results showed that ATR induced the increase of total CYP450 and Cytochrome b5 (Cyt b5) contents and stimulated the activities of CYP450s enzymes (erythromycin N-demethylase (ERND), aminopyrin N-demethylase (APND), aniline-4-hydeoxylase (AH) and NADPH-cytochrome c reductase (NCR)) in hepatic microsomes. The mRNA expressions of six CYP450s genes (increase: CYP1a1, CYP2a4, CYP3a57 and decrease: CYP2f2, CYP3a11, CYP4a31) were significantly influenced by ATR. LYC modulated the contents and activities of CYP450s and normalized the expressions of four CYP450s genes (CYP1b1, CYP2a4, CYP2e1, and 4A14). These findings suggested that ATR induced hepatic CYP450s disturbance and influenced the gene expression of CYP450s. Lycopene protected against hepatic CYP450s disturbance induced by ATR via modifying the hepatic CYP450s activities and transcription in mice.

Atrazine triggers developmental abnormality of ovary and oviduct in quails (Coturnix Coturnix coturnix) via disruption of hypothalamo-pituitary-ovarian axis.

There has been a gradual increase in production and consumption of atrazine (ATR) in agriculture to meet the population rising demands. Female reproduction is necessary for growth and maintenance of population. However, ATR impact on females and particularly ovarian developmental toxicity is less clear. The aim of this study was to define the pathways by which ATR exerted toxic effects on ovarian development of ovary and hypothalamo-pituitary-ovarian (HPO) axis. Female quails were dosed by oral gavage from sexual immaturity to maturity with 0, 50, 250 and 500 mg ATR/kg/d for 45 days. ATR had no effect on mortality but depressed feed intake and growth and influenced the biochemical parameters. Notably, the arrested development of ovaries and oviducts were observed in ATR-exposed quails. The circulating concentrations of E2, P, LH and PRL were unregulated and FSH and T was downregulated in ATR-treated quails. The mRNA expression of GnRH in hypothalamo and LH in pituitary and FSH in ovary was downregulated significantly by ATR exposure and FSH and PRL in pituitary were upregulated. ATR exposure upregulated the level of P450scc, P450arom, 3ß-HSD and 17ß-HSD in ovary and downregulated ERß expression in female quails. However, ATR did not change ERα expression in ovary. This study provides new insights regarding female productive toxicology of ATR exposure. Ovary and oviduct in sexually maturing females were target organs of ATR-induced developmental toxicity. We propose that ATR-induced developmental abnormality of ovary and oviduct is associated with disruption of gonadal hormone balance and HPO axis in female quails.