Assessment of triclosan induced histopathological and biochemical alterations, and molecular docking simulation analysis of acetylcholinesterase enzyme in the gills of fish, Cyprinus carpio.

Triclosan (TCS), an antimicrobial additive in various personal and health care products, has been widely detected in aquatic environment around the world. The present study investigated the impacts of TCS in the gills of the fish, Cyprinus carpio employing histopathological, biochemical, molecular docking and simulation analysis. The 96 h LC50 value of TCS in C. carpio was found to be 0.968 mg/L. Fish were exposed to 1/1000th (1 µg/L), 1/100th (10 µg/L), and 1/10th (100 µg/L) of 96 h LC50 value for a period of 28 days. The histopathological alterations observed in the gills were hypertrophy, hyperplasia, edematous swellings, and fusion of secondary lamellae in TCS exposed groups. The severity of these alterations increased with both the concentration as well as the duration of exposure. The present study revealed that the activity of antioxidant enzymes such as superoxide dismutase, catalase, glutathione-S-transferase, glutathione reductase, glutathione peroxidase, and reduced glutathione content decreased significantly (p < 0.05) in both concentration and duration dependent manner. However, a significant (p < 0.05) increase in the activity of the metabolic enzymes such as acid phosphatase and alkaline phosphatase was observed in all three exposure concentrations of TCS from 7 to 28 days. The activity of acetylcholinesterase declined significantly (p < 0.05) from 7 to 28 days whereas the content of acetylcholine increased significantly at the end of 28 day. The experimental results were further confirmed by molecular docking and simulation analysis that showed strong binding of TCS with acetylcholinesterase enzyme. The study revealed that long-term exposure to sublethal concentrations of TCS can lead to severe physiological and histopathological alterations in the fish.

Overexpression of GhGSTF9 Enhances Salt Stress Tolerance in Transgenic Arabidopsis.

Soil salinization is a major abiotic stress factor that negatively impacts plant growth, development, and crop yield, severely limiting agricultural production and economic development. Cotton, a key cash crop, is commonly cultivated as a pioneer crop in regions with saline-alkali soil due to its relatively strong tolerance to salt. This characteristic renders it a valuable subject for investigating the molecular mechanisms underlying plant salt tolerance and for identifying genes that confer salt tolerance. In this study, focus was placed on examining a salt-tolerant variety, E991, and a salt-sensitive variety, ZM24. A combined analysis of transcriptomic data from these cotton varieties led to the identification of potential salt stress-responsive genes within the glutathione S-transferase (GST) family. These versatile enzyme proteins, prevalent in animals, plants, and microorganisms, were demonstrated to be involved in various abiotic stress responses. Our findings indicate that suppressing GhGSTF9 in cotton led to a notably salt-sensitive phenotype, whereas heterologous overexpression in Arabidopsis plants decreases the accumulation of reactive oxygen species under salt stress, thereby enhancing salt stress tolerance. This suggests that GhGSTF9 serves as a positive regulator in cotton's response to salt stress. These results offer new target genes for developing salt-tolerant cotton varieties.

Praseodymium and warming interactions in mussels: Comparison between observed and predicted results.

Being a crucial element for technological development, praseodymium (Pr) has been increasingly used, leading to a rise in its concentration in aquatic systems. However, its potential threats to organisms remain poorly understood. Besides contamination, organisms are also threatened by climate change-related factors, including warming. It is important to evaluate how climate change-related factors may influence the effects of contaminants. To address this, histopathological and biochemical analyses were performed in adult mussels of Mytilus galloprovincialis, following a 28-day exposure to Pr (10 µg/L) and warming (4 °C increase) separately, and in combination. Additionally, biochemical and physiological alterations were analysed in the sperm of mussels after 30-min exposure to the same treatments. Furthermore, it was used the Independent Action model to predict the interaction between Pr and warming. The results showed, in the case of adults exposed to Pr, an increase in superoxide dismutase (SOD) and glutathione S-transferases (GSTs) activities. However, it was insufficient, leading to histopathological injuries, redox imbalance, and cellular damage. In the case of sperm, Pr induced an increase of mitochondrial activity and respiration rate, in response to the increase in systemic metabolic rate and oxygen demand. Warming increased the metabolism, and induced redox imbalance and cellular damage in adults. In sperm, a rise in temperature induced lipid peroxidation and a decrease in velocity. Warming induced some alterations in how adult mussels responded to Pr, activating catalase instead of SOD, and in addition to GSTs, also activated carboxylesterases. However, it was not enough to avoid redox imbalance and cellular damage. In the case of sperm, the combination induced a decrease in H2O2 production, and higher oxygen demand, which prevented the decrease in motility and velocity. This study highlights the limitations of using models and emphasizes the importance of studying the impacts of emerging contaminants, such as rare earth elements, and their combination with climate change-related factors. Under environmental conditions, chronic exposure to the combined effect of different stressors might generate impacts at higher biological levels. This may affect organisms' respiratory and filtration capacity, nutrient absorption, defence capacity against infections or diseases, and sperm viability, ultimately resulting in reduced growth and reproduction, with consequences at the population level.

Environmental assessment of the central Atlantic coast of Morocco using a multibiomarker approach in Mytilus galloprovincialis.

A multibiomarker approach helps assess environmental health as it provides a complete tool to understand the effects of environmental stressors on ecosystems and human health. We applied this approach in the central Atlantic Ocean of Morocco, an area subjected to the impact of many types of pollutants, threatening the durability of its resources. In this study, four biomarkers acetylcholinesterase (AChE), glutathione-s-transferase (GST), metallothioneins (MTs), and catalase (CAT) were measured in the digestive gland of the mussel Mytilus galloprovincialis collected from four sites: Imsouane (S1), Cap Ghir (S2), Imi Ouaddar (S3), and Douira (S4). These sites were chosen due to the diversity of impacts ranging from industrial to agricultural and touristic. We also assembled all the enzymatic responses (AChE, GST, CAT, and MTs), using the integrated biomarker response (IBR), to estimate the degree of impact of pollutants at the prospected sites to reveal all the complex interactions between biomarkers and to classify sites via the integrated approach. Results show a seasonal change in biomarker responses with variability between sites. We also recorded the highest levels of AChE inhibition and GST induction in S1, higher levels of catalase activity in S4, and a significant impact on metallothionein concentration in S1 and S3. This project highlights the interest in using a multibiomarker approach to ensure accurate interpretation of biomarker variation to protect the Moroccan coast and its resources.

Acute exposure and biomarkers assessment in rainbow trout exposed to selected pharmaceuticals.

Pharmaceuticals released from municipal effluents discharges pose a risk to aquatic organisms. The toxicity of 5 pharmaceuticals with distinct therapeutic actions were assessed in rainbow trout: olanzapine (antipsychotic), erythromycin (antibiotic), mycophenoate (immunosuppression), pinaverium (anti-inflammatory) and trazodone (sedative). Juveniles were exposed to these drugs for 96 h at concentrations between 64 µg/L up to 40 mg/L to reach lethality. Survival was determined and a suite of biomarkers was analyzed for drug biotransformation, oxidative stress/damage and metabolic activity at sublethal concentrations. The data revealed the following toxicity: olanzapine >trazodone>mycophenolate>pinaverium∼erythromycin based on mortality. The data also revealed that toxicity was associated to mass, pKa and hydrophobicity and the following sublethal effects: GST, LPO and DNA strand breaks. Pharmaceuticals with lower molecular weight, physiological pKa, moderate hydrophobicity, low biotransformation and DNA strand breaks were generally more toxic to fish. However, this should be considered as a general guide in identifying toxic pharmaceuticals in non-target organisms.

Systematic assessment of cyflumetofen toxicity in soil-earthworm (Eisenia fetida) microcosms.

Cyflumetofen was widely applied in agriculture with its excellent acaricidal effect. However, the impact of cyflumetofen on the soil non-target organism earthworm (Eisenia fetida) is unclear. This study aimed to elucidate the bioaccumulation of cyflumetofen in soil-earthworm systems and the ecotoxicity of earthworms. The highest concentration of cyflumetofen enriched by earthworms was found on the 7th day. Long-term exposure of earthworms to the cyflumetofen (10 mg/kg) could suppress protein content and increases Malondialdehyde content leading to severe peroxidation. Transcriptome sequencing analysis demonstrated that catalase and superoxide-dismutase activities were significantly activated while genes involved in related signaling pathways were significantly upregulated. In terms of detoxification metabolic pathways, high concentrations of cyflumetofen stimulated the number of Differentially-Expressed-Genes involved in the detoxification pathway of the metabolism of glutathione. Identification of three detoxification genes (LOC100376457, LOC114329378, and JGIBGZA-33J12) had synergistic detoxification. Additionally, cyflumetofen promoted disease-related signaling pathways leading to higher disease risk, affecting the transmembrane capacity and cell membrane composition, ultimately causing cytotoxicity. Superoxide-Dismutase in oxidative stress enzyme activity contributed more to detoxification. Carboxylesterase and glutathione-S-transferase activation play a major detoxification role in high-concentration treatment. Altogether, these results contribute to a better understanding of toxicity and defense mechanisms involved in long-term cyflumetofen exposure in earthworms.

Assessment of hazardous impact of nickel oxide nanoparticles on biochemical and histological parameters of gills and liver tissues of Heteropneustes fossilis.

BACKGROUND: The aim of the present study was to assess the hazardous impact of nickel oxide nanoparticles (NiO NPs) on gills and liver of Heteropneustes fossilis. METHODS: Fishes were treated with four concentrations of NiO NPs for a period of 14 days. Nickel accumulation, lipid peroxidation, antioxidant enzymes activities (superoxide dismutase, catalase, glutathione s transferase & glutathione reductase), liver enzymes activities (aspartate amino transferase, alanine transaminase, & alkaline phosphatase), Na+/K+ ATPase activity, FTIR, metallothionein content, ethoxyresorufin-o-deethylase activity, immunohistochemistry, histology and scanning electron microscopy were analyzed in both gills and liver tissues. RESULTS: Results revealed increased accumulation of nickel in both the tissues of exposed fishes. Lipid peroxidation and activities of different antioxidant enzymes increased (except superoxide dismutase) in both the tissues after exposure. Fluctuations in liver enzymes activities and variation in the activity of Na+/K+ ATPase were also observed. FTIR data revealed shift in peaks position in both the tissues. Level of metallothionein and its expression as well as activity of ethoxyresorufin-o-deethylase and expression of CYP1A also increased in both the target tissues of treated fishes. Furthermore, histological investigation and scanning electron microscopy showed structural damages in gills as well as liver tissues of exposed fishes. CONCLUSION: Our results suggest that NiO NPs cause deteriorating effects on the gill and liver tissues of fish, therefore effluents containing these nanoparticles should be treated before their release into water bodies.

Effects of salinity stress on antioxidant status and inflammatory responses in females of a "Near Threatened" economically important fish species Notopterus chitala: a mechanistic approach.

In the present study, acute stress responses of adult female Notopterus chitala were scrutinized by antioxidant status and inflammation reaction in the gill and liver at five different salinity exposures (0, 3, 6, 9, 12 ppt). Oxidative defense was assessed by determining superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase, and glutathione reductase activities, while malondialdehyde (MDA), glutathione, and xanthine oxidase levels were determined as indicators of oxidative load. Pro-inflammatory cytokines (IL-1ß, IL-6, IL-10, and TNFα) and caspase 1 levels were also analyzed. Expression levels of transcription factors (NRF2 and NF-κB) and molecular chaperons (HSF, HSP70, and HSP90) were estimated to evaluate their relative contribution to overcome salinity stress. MDA showed a significant (P < 0.05) increase (gill, + 25.35-90.14%; liver, + 23.88-80.59%) with salinity; SOD (+ 13.72-45.09%) and CAT (+ 12.73-33.96%) exhibited a sharp increase until 9 ppt, followed by a decrease at the highest salinity (12 ppt) (gill, - 3.92%; liver, - 2.18%). Levels of cytokines were observed to increase (+ 52.8-127.42%) in a parallel pattern with increased salinity. HSP70 and HSP90 expressions were higher in gill tissues than those in liver tissues. NRF2 played pivotal role in reducing salinity-induced oxidative load in both the liver and gills. Serum cortisol and carbonic anhydrase were measured and noted to be significantly (P < 0.05) upregulated in salinity stressed groups. Gill Na+-K+-ATPase activity decreased significantly (P < 0.05) in fish exposed to 6, 9, and 12 ppt compared to control. Present study suggests that a hyperosmotic environment induces acute oxidative stress and inflammation, which in turn causes cellular death and impairs tissue functions in freshwater fish species such as Notopterus chitala.

Ligandability Assessment of Human Glutathione Transferase M1-1 Using Pesticides as Chemical Probes.

Glutathione transferases (GSTs; EC 2.5.1.18) form a group of multifunctional enzymes that are involved in phase II of the cellular detoxification mechanism and are associated with increased susceptibility to cancer development and resistance to anticancer drugs. The present study aims to evaluate the ligandability of the human GSTM1-1 isoenzyme (hGSTM1-1) using a broad range of structurally diverse pesticides as probes. The results revealed that hGSTM1-1, compared to other classes of GSTs, displays limited ligandability and ligand-binding promiscuity, as revealed by kinetic inhibition studies. Among all tested pesticides, the carbamate insecticide pirimicarb was identified as the strongest inhibitor towards hGSTM1-1. Kinetic inhibition analysis showed that pirimicarb behaved as a mixed-type inhibitor toward glutathione (GSH) and 1-chloro-2,4-dinitrobenzene (CDNB). To shine a light on the restricted hGSTM1-1 ligand-binding promiscuity, the ligand-free crystal structure of hGSTM1-1 was determined by X-ray crystallography at 1.59 Å-resolution. Comparative analysis of ligand-free structure with the available ligand-bound structures allowed for the study of the enzyme's plasticity and the induced-fit mechanism operated by hGSTM1-1. The results revealed important structural features of the H-site that contribute to xenobiotic-ligand binding and specificity. It was concluded that hGSTM1-1 interacts preferentially with one-ring aromatic compounds that bind at a discrete site which partially overlaps with the xenobiotic substrate binding site (H-site). The results of the study form a basis for the rational design of new drugs targeting hGSTM1-1.

Single and joint toxicity assessment of acetamiprid and thiamethoxam neonicotinoids pesticides on biochemical indices and antioxidant enzyme activities of a freshwater fish Catla catla.

Neonicotinoids pesticides are extensively used in many countries due to their high insect selectivity. Acetamiprid and thiamethoxam are the neonicotinoids most commonly detected in the aquatic environment. This work examined the single and joint toxicity of acetamiprid and thiamethoxam in a freshwater fish Catla catla. Fish were exposed to acetamiprid (0.5 mg/L and 1 mg/L), thiamethoxam (0.01 mg/L and 0.5 mg/L) and their binary mixtures (0.5 mg/L of acetamiprid and 0.01 mg/L of thiamethoxam) for 96 h. The stress biomarkers such as glucose, protein, electrolytes, Na+/K+ -ATPase and oxidative stress were evaluated. Among the biochemical parameters, plasma protein, electrolytes (sodium, potassium and chloride) and gill ATPase activity were decreased in response to individual and binary mixtures treatments. In contrast, blood glucose level showed significant increase in all the treatments. Exposure to various concentrations of acetamiprid and thiamethoxam resulted in significant decrease in superoxide dismutase (SOD) activity in the gill tissue. However, SOD activity was significantly elevated during binary mixtures treatment. Glutathione peroxidase (GPx), catalase (CAT), glutathione-S-transferase (GST) and reduced glutathione (GSH) levels in gills were decreased significantly after individual and binary mixtures treatments. Fish exposed at individual and binary mixtures significantly elevated the level of LPO in gill tissue. Our findings suggest that multi-biomarker approach can be effectively used to assess the effects of joint toxicity of pesticides and to monitor the neonicotinoids pesticides in the aquatic environment.

A multi-biomarker approach for the early assessment of the toxicity of hospital wastewater using the freshwater organism Daphnia magna.

Hospital wastewater (HWW) contains different hazardous substances resulting from a combination of medical and non-medical activities of hospitals, including pharmaceutical residues. These substances may represent a threat to the aquatic environment if they do not follow specific treatment processes. Therefore, we aimed to investigate the effects of the untreated effluent collected from a general hospital in Mahdia City (Tunisia) on neonatal stages of the freshwater crustacean Daphnia magna. Test organisms were exposed to three proportions (3.12%, 6.25%, and 12.5% v/v) of HWW. After 48 h of exposure, a battery of biomarkers was measured, including the quantification of antioxidant enzymes [catalase (CAT) and total and selenium-dependent glutathione peroxidase (total GPx; Se-GPx)], phase II biotransformation isoenzymes glutathione-S-transferases (GSTs), cyclooxygenases (COX) involved in the regulation of the inflammatory process, and total cholinesterases (ChEs) activities. Lipid peroxidation (LPO) was measured to estimate oxidative damage. The here-obtained results showed significant decreases of CAT and GSTs activities and also on LPO content in daphnids, whereas Se-GPx activity was significantly increased in a dose-dependent manner. Impairment of cholinesterasic and COX activities were also observed, with a significant decrease of ChEs and an increase of COX enzymatic activities. Considering these findings, HWW was capable of inducing an imbalance of the antioxidant defense system, but without resulting in oxidative damage in test organisms, suggesting that peroxidases and alternative detoxifying pathways were able to prevent the oxidant potential of several drugs, which were found in the tested effluents. In general, this study demonstrated the toxicity of hospital effluents, measured in terms of the potential impairment of key pathways, namely neurotransmission, antioxidant defense, and inflammatory homeostasis of crustaceans.

Exposure to pollutants present in Iguaçu River Southern Brazil affect the health of Oreochromis niloticus (Linnaeus, 1758): Assessment histological, genotoxic and biochemical.

Urban sewage is a source of major contamination in aquatic systems and contributes to environmental and human health disturbances. This study investigates the effects of sewage-polluted waters from Iguaçu River on the health of juvenile Oreochromis niloticus. Two hundred four specimens were exposed to riverine water in four groups: no diluted, 25 and 50 % diluted water and a control group without tested water for 72 days. Biological samples were obtained for histopathological, neurotoxicity, antioxidant defenses, genotoxicity, metallothionines expression and polycyclic aromatic hydrocarbons (PAHs) metabolites. The results showed histopathological alterations in liver and gills, genotoxic alteration in erythrocytes, reduction of acetylcholinesterase activity in brain and muscle, activation of antioxidant defenses in the liver, recruitment of metals by metallothionein and the detection of PAHs metabolites in bile. These results demonstrate that juveniles of O. niloticus are susceptible to Iguaçu River exposure water and they can be used as indicator of water quality.

Identification of glutathione transferase gene associated with partial resistance to Sclerotinia stem rot of soybean using genome-wide association and linkage mapping.

KEY MESSAGE: Association and linkage mapping techniques were used to identify and verify single nucleotide polymorphisms (SNPs) associated with Sclerotinia sclerotiorum resistance. A novel resistant gene, GmGST , was cloned and shown to be involved in soybean resistance to SSR. Sclerotinia stem rot (SSR), caused by the fungus Sclerotinia sclerotiorum, is one of the most devastating diseases in soybean (Glycine max (Linn.) Merr.) However, the genetic architecture underlying soybean resistance to SSR is poorly understood, despite several mapping and gene mining studies. In the present study, the identification of quantitative trait loci (QTLs) involved in the resistance to S. sclerotiorum was conducted in two segregating populations: an association population that consisted of 261 diverse soybean germplasms, and the MH population, derived from a cross between a partially resistant cultivar (Maple arrow) and a susceptible cultivar (Hefeng25). Three and five genomic regions affecting resistance were detected by genome-wide association study to control the lesion length of stems (LLS) and the death rate of seedling (DRS), respectively. Four QTLs were detected to underlie LLS, and one QTL controlled DRS after SSR infection. A major locus on chromosome (Chr.) 13 (qDRS13-1), which affected both DRS and LLS, was detected in both the natural population and the MH population. GmGST, encoding a glutathione S-transferase, was cloned as a candidate gene in qDRS13-1. GmGST was upregulated by the induction of the partially resistant cultivar Maple arrow. Transgenic experiments showed that the overexpression of GmGST in soybean increased resistance to S. sclerotiorum and the content of soluble pigment in stems of soybean. The results increase our understanding of the genetic architecture of soybean resistance to SSR and provide a framework for the future marker-assisted breeding of resistant soybean cultivars.

Bioactivation of trichloroethylene to three regioisomeric glutathione conjugates by liver fractions and recombinant human glutathione transferases: Species differences and implications for human risk assessment.

Enzymatic conjugation of glutathione (GSH) to trichloroethylene (TCE) followed by catabolism to the corresponding cysteine-conjugate, S-(dichlorovinyl)-L-cysteine (DCVC), and subsequent bioactivation by renal cysteine conjugate beta-lyases is considered to play an important role in the nephrotoxic effects observed in TCE-exposed rat and human. In this study, it is shown for the first time that three regioisomers of GSH-conjugates of TCE are formed by rat and human liver fractions, namely S-(1,2-trans-dichlorovinyl)-glutathione (1,2-trans-DCVG), S-(1,2-cis-dichlorovinyl)-glutathione (1,2-cis-DCVG) and S-(2,2-dichlorovinyl)-glutathione (2,2-DCVG). In incubations of TCE with rat liver fractions their amounts decreased in order of 1,2-cis-DCVG > 1,2-trans-DCVG > 2,2-DCVG. Human liver cytosol showed a more than 10-fold lower activity of GSH-conjugation, with amounts of regioisomers decreasing in order 2,2-DCVG > 1,2-trans-DCVG > 1,2-cis-DCVG. Incubations with recombinant human GSTs suggest that GSTA1-1 and GSTA2-2 play the most important role in human liver cytosol. GSTP1-1, which produces regioisomers in order 1,2-trans-DCVG > 2,2-cis-DCVG > 1,2-cis-DCVG, is likely to contribute to extrahepatic GSH-conjugation of TCE. Analysis of the products formed by a beta-lyase mimetic model showed that both 1,2-trans-DCVC and 1,2-cis-DCVC are converted to reactive products that form cross-links between the model nucleophile 4-(4-nitrobenzyl)-pyridine (NBP) and thiol-species. No NBP-alkylation was observed with 2,2-DCVC corresponding to its low cytotoxicity and mutagenicity. The lower activity of GSH-conjugation of TCE by human liver fractions, in combination with the lower fraction of potential nephrotoxic and mutagenic 1,2-DCVG-isomers, suggest that humans are at much lower risk for TCE-associated nephrotoxic effects than rats.

Synthesis of novel 1,2,3 triazole derivatives and assessment of their potential cholinesterases, glutathione S-transferase enzymes inhibitory properties: An in vitro and in silico study.

In this study, new 1,2,3-triazole derivatives containing chalcone core (1-7) were synthesized. Obtained compounds were characterized by IR, 1H NMR, 13C NMR, and mass studies. Characterized compounds (1-7) inhibitory effects were tested against the glutathione S-transferase (GST), acetylcholinesterase (AChE), and Butyrylcholinesterase (BChE). Their Ki values were in the range of 5.88-11.13 µM on AChE, 5.08-15.12 µM on BChE, and 9.82-13.22 µM on GST. Remarkable inhibitory effects were obtained against three tested metabolic enzymes. Also, binding scores of the best-inhibitors against AChE, BChE, and GST enzymes were detected as -9.969 kcal/mol, -10.672 kcal/mol, and -8.832 kcal/mol, respectively. Isoindoline-1,3-dione and benzothiophene moieties played a critical role in the inhibition of AChE and BChE enzymes, respectively. Phenylene and triazole moieties had the most important interactions for inhibition of the GST enzyme. Therefore, in vivo and in silico results indicated that these compounds can be considered in drug design processes for the treatment of some diseases including Alzheimer's disease (AD), leukemia, and some type of cancer.

Synthesis, design, and assessment of novel morpholine-derived Mannich bases as multifunctional agents for the potential enzyme inhibitory properties including docking study.

The synthesized Schiff Bases were reacted with formaldehyde and secondary amine such as 2,6-dimethylmorpholine to afford N-Mannich bases through the Mannich reaction. 3-Substitued-4-(4-hydroxybenzylidenamino)-4,5-dihydro-1H-1,2,4-triazol-5-ones (4) were treated with 2,6-dimethylmorpholine in the presence of formaldehyde to synthesize eight new 1-(2,6-dimethylmorpholino-4-yl-methyl)-3-substitued-4-(4-hydroxybenzylidenamino)-4,5-dihydro-1H-1,2,4-triazol-5-ones (4a-h). The structures of the synthesized eight new compounds were characterized using IR, 1H NMR, 13C NMR, and HR-MS spectroscopic methods. Synthesized compounds inhibitory activity determined against the acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and glutathione S-transferase (GST) enzymes with Ki values in the range 25.23-42.19 µM for AChE, 19.37-34.22 µM for BChE, and 21.84-41.14 µM for GST, respectively. Binding scores of most active inhibitors against AChE, BChE, and GST enzymes were detected as -10.294 kcal/mol, -9.562 kcal/mol, and -7.112 kcal/mol, respectively. The hydroxybenzylidene moiety of the most active inhibitors caused to inhibition of the enzymes through hydrophobic interaction and hydrogen bond.

Human variability in glutathione-S-transferase activities, tissue distribution and major polymorphic variants: Meta-analysis and implication for chemical risk assessment.

The input into the QIVIVE and Physiologically-Based kinetic and dynamic models of drug metabolising enzymes performance and their inter-individual differences significantly improve the modelling performance, supporting the development and integration of alternative approaches to animal testing. Bayesian meta-analyses allow generating and integrating statistical distributions with human in vitro metabolism data for quantitative in vitro-in vivo extrapolation. Such data are lacking on glutathione-S-transferases (GSTs). This paper reports for the first time results on the human variability of GST activities in healthy individuals, their tissue localisation and the frequencies of their major polymorphic variants by means of extensive literature search, data collection, data base creation and meta-analysis. A limited number of papers focussed on in vivo GST inter-individual differences in humans. Ex-vivo total GST activity without discriminating amongst isozymes is generally reported, resulting in a high inter-individual variability. The highest levels of cytosolic GSTs in humans are measured in the kidney, liver, adrenal glands and blood. The frequencies of GST polymorphisms for cytosolic isozymes in populations of different geographical ancestry were also presented. Bayesian meta-analyses to derive GST-related uncertainty factors provided uncertain estimates, due to the limited database. Considering the relevance of GST activities and their pivotal role in cellular adaptive response mechanisms to chemical stressors, further studies are needed to identify GST probe substrates for specific isozymes and quantify inter-individual differences.

Assessment of DNA damage profile and oxidative /antioxidative biomarker level in patients with inflammatory bowel disease.

<b>Aim:</b> The purpose of this study was to investigate the oxidative DNA damage, pro-antioxidant status in Polish patients with inflammatory bowel disease (IBD). <br><b>Methods:</b> Oxidative DNA damage was measured by comet assay techniques; nitric oxide (NO) and plasmatic lipid peroxidation (MDA) as oxidative stress were valuated by colometric methods; superoxide dismutase (SOD1), catalase (CAT) and glutathione peroxidase (GPx1) as antioxidative defense were determined by spectrophotometric methods. <br><b>Results:</b> The level of oxidative DNA damage in IBD patients was significantly higher in relation to controls (P = 0.01). Alike, in control subject as well as in patients with IBD, lymphocytes are characterized by complete repair of DNA damage. A significant decrease of SOD (P = 0.031), CAT (P = 0.006), GPx1 (P = 0.001) activity was seen in IBD patients vs control. MDA (P = 0.001) and NO (P = 0.001) concentrations were significantly increased in IBD patients as compared to healthy subjects. <br><b>Conclusions:</b> Our results may be due to the induction of DNA repair genes which may occur at the stage of the pathological changes (IBD) that may be caused by excessive oxidative stress. However, the cause of this relationship, and whether it is direct or indirect, remains to be explored.

Comparative assessment of biomarker response to tissue metal concentrations in urban populations of the land snail Helix pomatia (Pulmonata: Helicidae).

The traffic pressure is increasing, resulting in the emission of atmospheric pollution. Soil organisms will need to respond to pollution stressors. Among them, land snails are valuable indicators of ecosystem disturbance. In this study, land snails Helix pomatia were sampled from three city localities with different traffic intensity. Oxidative stress biomarkers catalase (CAT), glutathione peroxidase (GPX), glutathione reductase (GR) and glutathione-S-transferase (GST) in the foot muscle (FM) and hepatopancreas (HP) tissue were determined. Also, five heavy metal (Cd, Cu, Ni, Pb, and Zn) concentrations were quantified in soil and tissue samples. According to the results, the highway induces the strongest contamination on the surrounding environment, with the highest metal concentrations measured in soil and snails. At the most polluted locality, only Cd exceeded some soil guidelines authorities that we referred to in this study. In addition, tissue Cd concentrations exceeded the United States Environmental Protection Agency (USEPA) value (1 mg kg-1) for soil invertebrate toxicity at all localities making it likely responsible for generating adverse effects in snails. Regarding HP, the CAT and GST are the most sensitive parameters that could be useful as oxidative stress biomarkers in snails exposed to the actual metals in the environment. On the other hand, in FM tissue, the most pronounced changes were recorded for GPX and GR. Based on tissue-specific enzyme responses, three urban populations were clearly separated. Therefore land snails are the promising candidates for quick field-based biomarker studies after showing a tissue-specific concentration-dependent induction of certain enzymes to heavy metals.

Antioxidative enzyme activities in the Rhodeinae sinensis Gunther and Macrobrachium nipponense and multi-endpoint assessment under tonalide exposure.

Tonalide or acetyl hexamethyl tetralin (AHTN) is used as a fragrance additive in various household products. Recently, AHTN has drawn attention owing to its negative health effects on aquatic organisms. Data on AHTN toxicity toward aquatic species are limited. Therefore, this study tested the oxidative stress induced by AHTN exposure on the Rhodeinae sinensis Gunther and Macrobrachium nipponense. In this study, malonaldehyde (MDA) content and the activities of acetyl cholinesterase (AchE), superoxide dismutase (SOD), glutathione S-transferase (GST), and catalase (CAT) in R. sinensis Gunther were tested after 30 days of exposure to 30.093, 34.005, 38.426, 43.421, 49.067, 55.444, 62.652, 70.800, and 80.000 µg/L AHTN, respectively. The MDA, AchE, SOD, GST and CAT in M. nipponense were tested after 40 days of exposure to 60.000, 72.000, 86.400, 103.680, 124.416, 149.299, 179.159, 214.991, and 257.989 µg/L AHTN, respectively. In addition, an integrated biomarker response (IBR) index was utilised to evaluate the integrated toxic effects of AHTN on R. sinensis Gunther and M. nipponense. Finally, the predicted no-effect concentrations (PNECs) of AHTN, based on reproduction, biochemistry, survival, chronic toxicity, and acute toxicity endpoints were derived. The results indicated that low concentrations of AHTN can induce significant changes of oxidative stress biomarkers. The no observed effect concentrations (NOECs) of SOD, GST, AchE, CAT, and MDA were 103.680, 72.000, <60.000, 72.000, and <60.000 µg/L for R. sinensis Gunther and 38.426, 43.421, 30.093, 30.093, and 38.426 µg/L for M. nipponense, respectively. The IBR calculation results showed that 149.299 µg/L AHTN caused the highest toxic effect on R. sinensis Gunther after 30 days of exposure, whereas 70.797 µg/L AHTN caused the greatest damage to M. nipponense after 40 days of exposure. The PNECs of AHTN based on the non-traditional endpoints of biochemistry and reproduction were 0.00145 µg/L and 0.000395 µg/L, respectively, which were significantly lower than the PNEC of 2.636 µg/L for traditional endpoint survival. Therefore, the protection of aquatic organisms based on non-traditional toxicity endpoints should be considered in ecological risk assessment.