Organotin Compounds Toxicity: Focus on Kidney

Switchable and Stereospecific C-Glycosylation Strategy via Formal Functional Group Deletion

Carbohydrates constitute an important class of biologically relevant natural products. Among the synthetic glycomimetics, C-glycosides are particularly interesting due to their chemical and metabolic stability toward acidic and enzymatic hydrolysis at the anomeric position. The stereochemical outcomes of traditional methodologies to access C-glycosides rely heavily on substrate control. Herein, we report a novel synthetic strategy to access diverse C-glycosides with precise stereochemical control at the anomeric position via formal functional group deletion, where both α- and β-anomers of furanoses and pyranoses can be obtained as single stereoisomers. Additionally, the broad scope of heterocyclic C-glycosides obtained via this strategy further illustrates its potential for empowering future application in both chemical biology research and drug discovery.

Analyzing the potential targets and mechanisms of chronic kidney disease induced by common synthetic Endocrine Disrupting Compounds (EDCs) in Chinese surface water environment using network toxicology and molecular docking techniques

Long-term exposure to NP and OP, as common synthetic endocrine-disrupting chemicals (EDCs) in surface water environments in China, is closely associated with the development of chronic kidney disease (CKD). However, their potential targets and toxicological mechanisms for inducing CKD remain unknown. This study utilizes network toxicology and molecular docking techniques to explore the potential toxic targets and molecular mechanisms of CKD induction by NP and OP. We identify 49 core targets of NP and OP action in CKD using the Comparative Toxicogenomics Database (CTD) and GeneCards databases. Using the STRING database and Cytoscape software, we identify five hub genes: MAPK3, TNF, BCL2, ESR1, and FOS. We construct a nomogram model based on the CKD dataset GSE66494, utilizing these five hub genes. Calibration and ROC curves demonstrate that the model has good diagnostic value for CKD, and the DCA curve indicates that the model has high clinical utility. Single-gene GSEA enrichment analysis identifies five hub genes that influence the development of CKD through multiple biological pathways, revealing that several immune-regulatory signaling pathways are activated. The CIBERSORT algorithm identifies eight types of immune cell infiltration levels that change significantly during CKD development, and correlation analyses suggest that the five hub genes are strongly associated with multiple immune cell infiltrations. The molecular docking results suggested that ESR1, MAPK3, and TNF had the lowest binding energies and high binding affinities with NP and OP. The results of molecular dynamics simulations similarly confirmed the stability of the interactions between ESR1, MAPK3 and TNF proteins with NP and OP. The results of this study provide a theoretical basis for understanding the potential toxicity targets and mechanisms of NP- and OP-induced CKD and promote the application of network toxicology and molecular docking techniques in the study of environmental pollutants.

Gut Dysbiosis and Probiotic Therapy in Chronic Kidney Disease: A Comprehensive Review

Chronic kidney disease (CKD) is a multifactorial disease affecting more than 13.4% of the world's population and is a growing public health problem. It is silent in its early stages and leads to irreversible kidney damage as the disease progresses. A key factor in this progression is the bidirectional relationship between CKD and gut dysbiosis, which creates an imbalance that promotes the accumulation of uremic toxins (UTs), contributing to renal fibrosis, endothelial dysfunction, and decreased glomerular filtration rate. In addition, CKD itself exacerbates gut dysbiosis by altering the composition of the gut microbiota (GM) and promoting the growth of pathogenic microorganisms. Therefore, it is crucial to explore new therapeutic strategies, and the use of probiotics and synbiotics has shown promise in modulating the GM. Numerous preclinical studies have shown that the use of probiotics in CKD has a beneficial effect on the kidney by reducing UTs, apoptosis, inflammation, and oxidative stress. Probiotic treatment has also been associated with restoration of intestinal integrity, modulation of microbial composition and diversity, and increased production of short-chain fatty acids (SCFAs). These positive results have also been observed in patients at different stages of CKD, where the use of probiotics and/or synbiotics was able to improve creatinine levels and uremic parameters and alleviate abdominal discomfort, in addition to modulating GM and reducing serum endotoxin levels. Although recent studies have explored the benefits of probiotics in the treatment of CKD, further research is needed to determine their long-term efficacy and clinical relevance. This review focuses on the factors driving gut dysbiosis in CKD, its role in disease progression, and the potential of probiotics as a therapeutic strategy.

Association between serum and urinary environmental metal levels and major depressive disorder: a study based on logistic regression and quantile regression

Background

Major depressive disorder (MDD) is a prevalent mental disorder globally. Increasing evidence suggests that Environmental Metal (EM) play a crucial role in MDD. Therefore, this study investigated the roles of barium (Ba), cesium (Cs), nickel (Ni), manganese (Mn), lead (Pb), mercury (Hg), cadmium (Cd), and tin (Sn) in the etiology of MDD.

Methods

The study included 72 MDD patients and 75 healthy controls (HCs) from the Second People's Hospital of Zhumadian, China. Inductively coupled plasma mass spectrometer (ICP-MS) measured the metal levels in serum and urine samples from both groups.

Results

Significant differences in serum and urine levels of EMs were observed between MDD patients and HCs. After adjusting for age, gender, and BMI, logistic regression and quantile regression models revealed significant associations between EMs and MDD. In serum samples, higher Sn levels (OR = 1.22, p = 0.044) increased MDD risk, whereas higher Cs levels (OR = 0.02, p < 0.001), Cd (OR = 0.06, p = 0.047), and Mn (OR = 0.54, p = 0.016) decreased MDD risk. In urine samples, higher Ba levels (OR = 0.94, p = 0.015), Ni (OR = 0.87, p = 0.0024), Sn (OR = 1.62, p < 0.001), and Mn (OR = 0.77, p = 0.037) were significantly associated with MDD. Sn significantly positively predicted HAMD-24 scores at the 0.50 and 0.75 quantiles (β = 0.96, p = 0.018; β = 1.25, p = 0.008) as did Pb (β = 5.15, p = 0.001; β = 4.19, p = 0.004). Ba positively predicted depressive symptoms across all quantiles (all p < 0.05). Hg positively predicted HAMD-24 scores at the 0.50 quantile (β = 9.20, p = 0.050).

Conclusion

These findings underscore EMs' importance in depression, aiding in targeted interventions for varying degrees of depression and necessitating future studies to clarify causality and mechanisms.

Navigating challenges and solutions for metal-halide and carbon-based electrodes in perovskite solar cells (NCS-MCEPSC): An environmental approach

The urgent need to shift to renewable energy is highlighted by rising global energy use and environmental issues like global warming from fossil fuel dependency. Perovskite solar cells (PSCs) stand out as a promising option, providing high efficiency and potential for cost-effective production. This study delves into the environmental concerns and viable solutions linked with metal-halide PSCs (M-PSCs) and carbon-based electrode PCSs (C-PSCs). It showcases the swift progress in PSC technology, highlighting its potential to deliver efficient and economical renewable energy options. Yet, the environmental implications of these technologies, especially the utilization of toxic lead (Pb) in M-PSCs and the issues of stability and degradation in C-PSCs, represent considerable hurdles for their broad application and sustainability. The paper details the recent advances in PSCs, focusing on enhancements in device efficiency and stability through innovative material combinations and device designs. Nonetheless, the environmental hazards linked to the dispersal of toxic substances from compromised or deteriorating PSCs into the ecosystem raise significant concerns. In particular, the risk of Pb from M-PSCs contaminating soil and aquatic ecosystems is a pressing issue for human and environmental health, spurring investigations into alternative materials and methods to diminish these impacts. The authors examine several strategies, including the introduction of Pb-free perovskites, encapsulation methods to block the escape of hazardous substances, and the recycling of PSC elements. The study stresses the necessity of aligning technological innovations with considerations for the environment and health, calling for ongoing research into PSC technologies that are sustainable and safe. This review highlights the need for detailed assessments of PSC technologies, focusing on their renewable energy contributions, environmental impacts, and strategies to mitigate these effects. The authors call for a cohesive strategy to develop PSCs that are efficient, cost-effective, eco-friendly, and safe for widespread use.

Testicular protective effects of hesperidin against chemical and biological toxicants

Toxic agents can adversely impact the male reproductive system mainly via activating oxidative stress affecting the seminiferous epithelia, spermatogenesis, sperms, and the testis. Toxic agents lead to the excessive generation of reactive oxygen species (ROS), such as hydroxyl radicals, hydrogen peroxide, and superoxide anions. ROS exert a cytotoxic effect and oxidative damage to nucleic acids, proteins, and membrane lipids. Hesperidin is a pharmacologically active phytoflavone abundantly occurring in citrus fruits, such as oranges and lemons. It has shown various pharmacological properties such as antioxidant, anti-inflammatory, anti-carcinogenic, analgesic, antiviral, anti-coagulant, hypolipidemic, and hypoglycemic effects. Hesperidin has been found to exert protective effects against natural and chemical toxins-induced organ toxicity. Considerable evidence has implicated the testicular protective effects of hesperidin against the toxicological properties of pharmaceutical drugs as well as biological and chemical agents, and in the present review, we discussed, for the first time, the reported studies. The resultant data indicate that hesperidin can exert testicular protective effects through antioxidant properties.

Biodegradation of pesticide in agricultural soil employing entomopathogenic fungi: Current state of the art and future perspectives

Pesticides play a pivotal role in agriculture for the effective production of various crops. The indiscriminate use of pesticides results in the significant bioaccumulation of pesticide residues in vegetables. This situation is beyond the control of consumers and poses a serious health issue for human beings. Occupational exposure to pesticides may occur for farmers, agricultural workers, and industrial producers of pesticides. This occupational exposure primarily causes food and water contamination that gets into humans and environmental pollution. Depending on the toxicity of pesticides, the causes and effects differ in the environment and in human health. The number of criteria used and the method of implementation employed to assess the effect of pesticides on humans and the environment have been increasing, as they may provide characterization of pesticides that are already on the market as well as those that are on the way. The biological control of pests has been increasing nowadays to combat all these effects caused by synthetic pesticides. Myco-biocontrol has received great attention in research because it has no negative impact on humans, the environment, or non-target species. Entomopathogenic fungi are microbes that have the ability to kill insect pests. Fungi also make enzymes like the lytic enzymes, esterase, oxidoreductase, and cytochrome P450, which react with chemical residues in the field and break them down into nontoxic substances. In this review, the authors looked at how entomopathogenic fungi break down insecticides in the environment and how their enzymes break down insecticides on farms.

TMT-based quantitative proteomics analysis of Sprague-Dawley rats liver reveals Triphenyltin induced liver damage and lipid metabolism disorders

Triphenyltin (TPT) is a widely used pesticide that has a negative impact on biological health and production efficiency. In addition, TPT poses a threat to human health through the food chain and environmental pollution. However, the exact mechanism of TPT toxicity remains unclear. In this study, we investigated the hepatotoxicity of TPT and its effects on lipid metabolism using male SD rats as an animal model. Our results from HE and serum biochemical analysis suggested that TPT could damage liver structure and function, resulting in disruption of lipid metabolism. We therefore proceeded to analyze the proteomic response of rat liver tissue after 28 days of treatment with 2 mg/kg/d TPT. Our study demonstrates that TPT has a variety of effects on liver protein expression in rats. Through bioinformatic analysis, we observed significant changes in proteins related to fatty acid oxidation and synthesis due to TPT exposure. Furthermore, western blot and RT-qPCR experiments confirmed that TPT can affect lipid metabolism through the PPAR pathway. These findings suggest that TPT exposure can lead to liver damage, lipid accumulation and metabolic disorders.

Endoplasmic Reticulum Stress and Autophagy Are Involved in Hepatotoxicity Induced by Tributyltin

Tributyltin (TBT), a common contaminant in aquatic ecosystems, has severe toxic effects on multiple tissues and organs, especially the liver. Previous toxicogenomic analysis has indicated that the main mechanism of TBT-induced hepatotoxicity is related to the activation of the apoptotic pathway. However, the mechanism of action occurring before the activation of apoptosis is still unclear. Herein, we applied proteomic technology to explore the protein expression profile of TBT-treated HL7702 normal human liver cells. The ultrastructural changes in cells were observed by transmission electron microscopy. After low dose (2 μΜ) TBT treatment, activation of the unfolded protein response and endoplasmic reticulum stress were observed; the expression levels of PERK, ATF6, BiP, and CHOP were significantly elevated, and splicing of XBP1 mRNA was initiated. When the TBT concentration increased to 4 μΜ, the protein levels of Beclin1, Atg3, Atg5, Atg7, and Atg12-Atg5 were significantly elevated, and the protein level of LC3Ⅰ decreased while that of LC3Ⅱ increased, suggesting the activation of autophagy. As the TBT concentration continued to increase, autophagy could not eliminate the damage, and apoptosis eventually occurred. These results indicate novel pathways of hepatotoxicity induced by TBT and provide insights for future studies.

Evaluating the histomorphological and biochemical changes induced by Tributyltin Chloride on pituitary-testicular axis of adult albino rats and the possible ameliorative role of hesperidin

This study was performed to explore in detail the toxic effects of Tributyltin Chloride (TBT) on the pituitary-testicular axis and the possible amelioration with Hesperidin. Seventy-two adult male albino rats were divided into four groups: Control group (I), TBT-treated group (II), TBT+Hesperidin group (III), and Recovery group (IV). Body and testicular weights were measured. Blood samples were taken to estimate serum levels of testosterone, FSH and LH hormones by enzyme-linked immunosorbent assay (ELISA). Malondialdehyde (MDA) level was measured in testes homogenates. Tissue samples from the pituitary glands and testes were processed for light, electron microscope examination, and immunohistochemical detection of anti-FSH, and Ki67 proteins. Results showed a statistically significant decrease in testicular weight, serum testosterone, FSH and LH levels and a significant increase in tissue MDA in the TBT group when compared to the control group. TBT treatment caused severe histopathological changes with decreased area percent of PAS-stained basophils, and anti FSH immuno-stained gonadotrophs in the pituitary gland. The testes of group II also showed marked tissue damage, cell loss with decreased epithelial height and decreased number of proliferating spermatogenic cells. Hesperidin supplementation with TBT proved significant amelioration of the previously mentioned parameters in both glands which could improve male fertility. In conclusion: The flavonoid Hesperidin has the potential to protect against the reproductive damage induced by TBT in susceptible individuals.

Environmental impact of metal halide perovskite solar cells and potential mitigation strategies: A critical review

Metal halide perovskite solar cells (PSCs) have gained extensive attention in the field of solar photovoltaic technology over the past few years. Despite being a remarkable alternative to fossil fuels, solar cells may have detrimental effects on the environment and human health owing to the use of toxic materials during manufacturing. Although modern metal-halide-based PSCs are stable and have encapsulation to prevent the release of potentially toxic materials into the environment, their destruction due to strong winds, hail, snow, landslides, fires, or waste disposal can result in the exposure of these materials to the environment. This may lead to the contamination of soil and groundwater, and uptake of potentially toxic elements by plants, subsequently affecting humans and other living organisms via food chain contamination. Despite worldwide concern, the environmental and ecotoxicological impacts of metal-halide-based PSCs have not been comprehensively surveyed. This review summarizes and critically evaluates the current status of metal-halide-based PSC production and its impact on environmental sustainability, food security, and human health. Furthermore, safe handling and disposal methods for the waste generated from metal-halide-based PSCs are proposed, with a focus on recycling and reuse. Although some studies have suggested that the amount of lead released from metal halide PSCs is far below the maximum permissible levels in most soils, a clear conclusion cannot be reached until real contamination scenarios are assessed under field conditions. Precautions must be taken to minimize environmental contamination throughout the lifecycle of PSCs until nontoxic and similarly performing alternative solar photovoltaic products are developed.

Trimethyltin induces apoptosis and necroptosis of mouse liver by oxidative stress through YAP phosphorylation

Trimethyltin (TMT) is widely used as a major component of plastic stabilizers in agriculture and industry, and can accumulate in large quantities in the liver. To investigate the relationship between liver tissue damage induced by TMT exposure and YAP phosphorylation in mice, we gave the mice drinking water containing 0.01 mg/mL TMT for 14 days to establish an in vivo experimental model, and continuously treated AML12 cells with 20 μM TMT for 24 h to establish an in vitro experimental model. Transcriptomics revealed that TMT exposure altered 62,466 apparently diversely expressed genes, including 1197 upregulated and 899 downregulated genes, and that enrichment of the Hippo pathway occurred. Moreover, western blotting (WB) and quantitative real-time PCR (qRTPCR) results showed that TMT exposure triggered an increase in the expression of P-YAP, apoptosis and necroptosis-interrelated genes, and a decrease in Bcl-2 expression in mouse livers tissues and AML12 cells. The expression of P-YAP was significantly suppressed in the TRULI-treated TMT-exposed AML12 cells, while oxidative stress levels and damage were also significantly attenuated. In conclusion, TMT triggers YAP phosphorylation to induce oxidative stress inducing apoptosis and necroptosis in mouse livers tissues. Our results confirm the liver toxic effect and specific mechanism of TMT.

Oxidation-Cyclisation of Biphenyl Thioethers to Dibenzothiophenium Salts for Ultrarapid 18F-Labelling of PET Tracers

¹⁸F-labelled radiotracers are in high demand and play an important role for diagnostic imaging with positron emission tomography (PET). Challenges associated with the synthesis of the labelling precursors and the incorporation of [¹⁸F]fluoride with practical activity yields at batch scale are the main limitations for the development of new ¹⁸F-PET tracers. Herein, we report a high-yielding and robust synthetic method to access naked dibenzothiophenium salt precursors of complex PET tracers and their labelling with [¹⁸F]fluoride. C-S cross-coupling of biphenyl-2-thioacetate with aryl halides followed by sequential oxidation-cyclisation of the corresponding thioethers gives dibenzothiophenium salts in good to excellent yields. Labelling of neutral and electron-deficient substrates with [¹⁸F]fluoride is ultrarapid and occurs under mild conditions (1 min at 90 °C) with high activity yields. The method enables facile synthesis of complex and sensitive radiotracers, as exemplified by radiofluorination of three clinically relevant PET tracers [¹⁸F]UCB-J, [¹⁸F]AldoView and [¹⁸F]FNDP, and can accelerate the development and clinical translation of new ¹⁸F-radiopharmaceuticals.

Elemental Speciation Analysis in Environmental Studies: Latest Trends and Ecological Impact

Speciation analysis is a key aspect of modern analytical chemistry, as the toxicity, environmental mobility, and bioavailability of elemental analytes are known to depend strongly on an element’s chemical species. Henceforth, great efforts have been made in recent years to develop methods that allow not only the determination of elements as a whole, but also each of its separate species. Environmental analytical chemistry has not ignored this trend, and this review aims to summarize the latest methods and techniques developed with this purpose. From the perspective of each relevant element and highlighting the importance of their speciation analysis, different sample treatment methods are introduced and described, with the spotlight on the use of modern nanomaterials and novel solvents in solid phase and liquid-liquid microextractions. In addition, an in-depth discussion of instrumental techniques aimed both at the separation and quantification of metal and metalloid species is presented, ranging from chromatographic separations to electro-chemical speciation analysis. Special emphasis is made throughout this work on the greenness of these developments, considering their alignment with the precepts of the Green Chemistry concept and critically reviewing their environmental impact.

Modified, optimized method of determination of Tributyltin (TBT) contamination in coastal water, sediment and biota in Sri Lanka

Tributyltin (TBT) is a toxic organotin compound that belongs to the group of Persistent Organic Pollutants (POPs) and it is documented to cause severe sexual disorders development in aquatic fauna. According to the present study, The TBT concentration in coastal water ranged from 303 ± 7.4 ngL^-1 to 25 ± 4.2 ngL^-1 wherein sediment was from 107 ± 4.1 ngKg^-1 to 17 ± 1.4 ngKg^-1. TBT in Perna viridis was found to range from 4 ± 1.2 ngKg^-1 to 42 ± 2.2 ngKg^-1 wet weight and in ascending order of the body weight. The highest TBT level in water and sediment was found in the Colombo port where the highest level of TBT in P. viridis (42 ± 2.2 ngKg^-1) was recorded from the Dikkowita fishery harbor. A positive correlation between the number of male P. viridis and TBT level (p < 0.05) suggests possible reproductive impairment in aquatic animals exposed continuously to a high concentration of TBT.

Serum trace metal association with response to erythropoiesis stimulating agents in incident and prevalent hemodialysis patients

Alterations in hemodialysis patients' serum trace metals have been documented. Early studies addressing associations levels of serum trace metals with erythropoietic responses and/or hematocrit generated mixed results. These studies were conducted prior to current approaches for erythropoiesis stimulating agent (ESA) drug dosing guidelines or without consideration of inflammation markers (e.g. hepcidin) important for regulation of iron availability. This study sought to determine if the serum trace metal concentrations of incident or chronic hemodialysis patients associated with the observed ESA response variability and with consideration to ESA dose response, hepcidin, and high sensitivity C-reactive protein levels. Inductively-coupled plasma-mass spectrometry was used to measure 14 serum trace metals in 29 incident and 79 prevalent dialysis patients recruited prospectively. We compared these data to three measures of ESA dose response, sex, and dialysis incidence versus dialysis prevalence. Hemoglobin was negatively associated with ESA dose and cadmium while positively associated with antimony, arsenic and lead. ESA dose was negatively associated with achieved hemoglobin and vanadium while positively associated with arsenic. ESA response was positively associated with arsenic. Vanadium, nickel, cadmium, and tin were increased in prevalent patients. Manganese was increased in incident patients. Vanadium, nickel, and arsenic increased with time on dialysis while manganese decreased. Changes in vanadium and manganese were largest and appeared to have some effect on anemia. Incident and prevalent patients' chromium and antimony levels exceeded established accepted upper limits of normal.

Metals and Metalloids Release from Orthodontic Elastomeric and Stainless Steel Ligatures: In Vitro Risk Assessment of Human Exposure

Elastomeric ligatures are increasingly used as a part of esthetic orthodontic treatment, particularly in children. The aim of the present study was to experimentally test whether these appliances may contribute to exposure to toxic elements. In the present study, elastomeric ligatures (ELs) were incubated in artificial human saliva for 1 month (a typical period of their use) and the release of 21 metals (Ba, Cd, Co, Cr, Cu, Fe, Li, Mn, Mg, Mo, Ni, Pb, Rb, Tl, Ti, Sb, Sr, Sn, Zn, U, V) and 2 metalloids (As and Ge) was studied using inductively coupled plasma-mass spectrometry. For comparison, stainless steel ligatures (SLs) were incubated for 1, 3, and 6 months (since sometimes their use is prolonged) under similar conditions. The determined metal levels were compared to the corresponding safety limits for human exposure. During 1 month, the ELs released Cd, Co, Cr, Mn, Ni, and Sn at total mean ± SD level of 0.31 ± 0.09, 0.98 ± 0.30, 3.96 ± 1.31, 14.7 ± 8.5, 13.8 ± 4.8, and 49.5 ± 27.7 μg, respectively. Other elements were always below the detection limits. In case of SL, the release of Co, Cr, Fe, Ni, Mn, and Sn was observed, and the determined values increased over the studied period. After 6 months, their total mean ± SD levels amounted to 28.6 ± 0.2, 21.7 ± 0.2, 623.5 ± 3.0, 1152.7 ± 1.8, 5.5 ± 0.3, and 22.6 ± 0.2 μg, respectively. The released metal levels from both ligature types were always below safety limits. The release of Ni from SL during 6 months would constitute 5.0 and 11.5% of tolerable intake in adults and children, respectively. The results of this in vitro study highlight that the use of ligatures in orthodontic treatment can be considered safe in terms of metal exposure although elastic ligatures replaced on a monthly basis appear to be advantageous in comparison to the prolonged use of stainless steel appliances.

Glucocorticoid and mineralocorticoid receptors and corticosteroid homeostasis are potential targets for endocrine-disrupting chemicals

Endocrine-disrupting chemicals (EDCs) have received significant concern, since they ubiquitously exist in the environment and are able to induce adverse health effects on human and wildlife. Increasing evidence shows that the glucocorticoid receptor (GR) and the mineralocorticoid receptor (MR), members of the steroid receptor subfamily, are potential targets for EDCs. GR and MR mediate the actions of glucocorticoids and mineralocorticoids, respectively, which are two main classes of corticosteroids involved in many physiological processes. The effects of EDCs on the homeostasis of these two classes of corticosteroids have also gained more attention recently. This review summarized the effects of environmental GR/MR ligands on receptor activity, and disruption of corticosteroid homeostasis. More than 130 chemicals classified into 7 main categories were reviewed, including metals, metalloids, pesticides, bisphenol analogues, flame retardants, other industrial chemicals and pharmaceuticals. The mechanisms by which EDCs interfere with GR/MR activity are primarily involved in ligand-receptor binding, nuclear translocation of the receptor complex, DNA-receptor binding, and changes in the expression of endogenous GR/MR genes. Besides directly interfering with receptors, enzyme-catalyzed synthesis and prereceptor regulation pathways of corticosteroids are also important targets for EDCs. The collected evidence suggests that corticosteroids and their receptors should be considered as potential targets for safety assessment of EDCs. The recognition of relevant xenobiotics and their underlying mechanisms of action is still a challenge in this emerging field of research.

Triphenyltin exposure alters the antioxidant system, energy metabolism and the expression of genes related to physiological stress in zebrafish (Danio rerio)

The adverse influences of triphenyltin (TPT) on aquatic system have been of great concern due to their widespread use and ubiquity in water environment. Here, zebrafish larvae (7 days after hatching) were exposed to TPT for 14 days to study its toxicity on the antioxidant system, energy metabolism and the expression of genes related to physiological stress. Results shows that the oxidative stress was generated in fish larvae exposed to TPT with higher concentrations (10 and/or 100 ng/l), and the energy metabolic parameters (RNA/DNA ratio, Na + -K + -ATPase) were significantly inhibited in fish exposed to 100 ng/l TPT. Additional, the expression levels of genes related to physiological stress were up-regulated in a dose-dependent manner, including heat shock protein70 (hsp70) and metallothionein (mt). Moreover, the PERK-eIF2α pathway was found as the main branch activated by TPT exposure in fish larvae. Thus, TPT-induced antioxidant responses, energy metabolism disorder and physiological stress in fish larvae were reflected by the parameters measured, which could provide some useful information for full understanding the exact mechanisms of TPT toxicity.