Glutathione S-transferase Enzyme Activity Research Articles

Biochemical changes and bioaccumulation of manganese in Astyanax lacustris (Teleostei: Characidae).

Major tailings dam failures have occurred recently around the world and resulted in severe environmental impacts, such as metal contamination. Manganese is a metal highly associated with mining activities, largely detected in mining dam collapses. This metal is considered necessary for different organisms, but it can be toxic and cause oxidative stress and genetic damage in fishes. In this study, we investigated the toxic effects of manganese on Astyanax lacustris, by exposing the fish individually to different concentrations of this metal (2.11, 5.00, and 10.43 mg/L) for 96 h. To assess the effects of manganese, we used biochemical biomarkers (glutathione S-transferase, catalase, and acetylcholinesterase enzyme activity) and the manganese bioaccumulation in different tissues (liver and gills). The obtained data showed that only at concentrations of 5.00 mg/L and 10.43 mg/L the activity of glutathione S-transferase differed significantly. Additionally, the acetylcholinesterase activity in the brain tissue was inhibited. The highest level of manganese bioaccumulation was observed in the liver and branchial tissue. Overall, we concluded that high concentrations of manganese may cause physiological changes in Astyanax lacustris.

Polycyclic aromatic hydrocarbon (PAH) activation of AhR inhibits glutathione S-transferase (GST) activity in primary human small airway epithelial cells (hSAECs)

Background: PAH represents the organic phase of particulate matter (PM) in air pollution emitted via the incomplete combustion of various compounds (i.e. diesel fuel, wood, and plastics). It is widely regarded that PAH activation of aryl hydrocarbon receptor (AhR) plays an important role in pro-inflammatory signaling, however the mechanisms remain unknown. In contrast- endogenous AhR agonists, such as 6-Formylindolo[3,2-b]carbazole (FICZ), exert pleiotropic protective effects against inflammation, fibrosis, and oxidative stress. The objective of our research program is to delineate the differences between activation of AhR by PAH (with adverse effects) compared to its beneficial homeostatic activation by endogenous FICZ. PM may induce oxidative stress in part through inhibition of antioxidant defense mechanisms. GSTs are a superfamily of enzymes that plays an important role in protecting cells from oxidative damage (by conjugating reduced glutathione to substrates under pro-oxidizing conditions). We hypothesize that PAH activation of AhR contributes to oxidative stress via inhibition of GST activity in primary hSAECs. Methods: Primary hSAECs were subjected to varying dosages of PAH [0, 250, 500, 1000, 5000 ng/mL] to model airborne PM exposure levels, and to increasing doses of FICZ [0, 0.50, 10, 100, 1000 nM] to model normal and excessively high endogenous ligand activation of AhR. We determined the relative potencies of PAH and FICZ by measuring CYP1A1 and CYP1B1 gene expression. Oxidative stress was measured using DHE-labeling and GST activity was measured with enzymatic kits (Sigma Aldrich). AhR activity was pharmacologically inhibited using 10μM CH223191. Statistical analysis was conducted using SigmaPlot 14.0 (Systat Software). Results: PAH and FICZ maximally stimulate hSAEC CYP1A1 and CYP1B1 expression at 1000ng/mL and 100nM, respectively, and are therefore defined as equipotent concentrations used in our studies. In a representative experiment in hSAECs, PAH (1000ng/mL) significantly increased hSAEC oxidative stress vs FICZ (100nM) n=6, p<0.01), while significantly decreasing GST specific activity vs equipotent FICZ activation of AhR in primary hSAECs from a 66-year-old female without lung disease (26.6±0.874 vs 28.3±.611 nmol/mL/min); n=6 from 2 independent assays; p=0.032. Similar differential effects of PAH vs FICZ activation of AhR on GST were seen in additional experiments with male hSAECs and Calu-3 cells (male). Importantly, CH223191 inhibition of GST enzymatic activity suggests that AhR plays an important role in protecting cells from oxidative stress. Conclusions: Our studies indicate that airborne PAH exposure can have detrimental health effects on the lung via aberrant AhR signaling. Significance: Understanding activity of AhR signaling can leads to novel therapeutic options for redox disorders in the lung. Funding: VA 5I01BX001777-05 (RP) and R01HL137033 (MH). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Assessing the impact of antiviral drugs commonly utilized during the COVID-19 pandemic on the embryonic development of Xenopus laevis

The antiviral drugs favipiravir and oseltamivir are widely used to treat viral infections, including coronavirus 2019 (COVID-19), and their levels are expected to increase in the aquatic environment. In this study, the potential toxic and teratogenic effects of these drugs were evaluated using the frog embryo teratogenesis assay Xenopus (FETAX). In addition, glutathione S-transferase (GST), glutathione reductase (GR), catalase, carboxylesterase (CaE), and acetylcholinesterase (AChE) enzyme activities and malondialdehyde levels were measured as biochemical markers in embryos and tadpoles for comparative assessment of the sublethal effects of the test compounds. Prior to embryo exposure, drug concentrations in the exposure medium were measured with high-performance liquid chromatography. The 96-h median lethal concentration (LC50) was 137.9 and 32.3 mg/L for favipiravir and oseltamivir, respectively. The teratogenic index for favipiravir was 4.67. Both favipiravir and oseltamivir inhibited GR, CaE, and AChE activities in embryos, while favipiravir increased the GST and CaE activities in tadpoles. In conclusion, favipiravir, for which teratogenicity data are available in mammalian test organisms and human teratogenicity is controversial, inhibited Xenopus laevis embryo development and was teratogenic. In addition, sublethal concentrations of both drugs altered the biochemical responses in embryos and tadpoles, with differences between the developmental stages.

Toxicity assays and in silico approach to assess the impacts of chlorine dioxide on survival, respiration and some biochemical markers of marine zooplankton

Chlorination is the common antifouling method in desalination and power plant water intake structures to control microbial and macrofouling growth. In this study, the impacts of chlorine dioxide on toxicity, metabolic activity and biochemical markers like glutathione S-transferase and catalase enzyme activity were tested using four zooplankton species (Centropages sp., Acartia sp., Oncaea sp., and Calanus sp.) collected from the Red Sea. The zooplankton species were treated with different concentrations (0.02, 0.05, 0.1, 0.2, and 0.5 mg L−1) of chlorine dioxide. Further, chlorite, the main decomposition product of chlorine dioxide, was used for molecular docking studies against glutathione S-transferase and catalase enzymes. The results indicated the LC50 range of 0.552–1.643 mg L−1 for the studied zooplankton species. The respiration rate of the zooplankton increased due to the chlorine dioxide treatment with a maximum of 0.562 μg O2 copepod h−1 in Acartia. The glutathione S-transferase and catalase enzyme activities showed elevated values in zooplankton treated with chlorine dioxide. Molecular docking of chlorite with enzymes involved in antioxidant defense activity, such as glutathione S-transferase and catalase enzyme showed weak interactions. Overall, this study yielded significant insights for understanding the effects of chlorine dioxide on the survival, metabolism, and biochemical composition of marine zooplankton.

The roles of the biochemical and molecular changes in resistance of Tetranychus urticae populations selected with spiromesifen+abamectin mixture </p >

The physiological changes in Tetranychus urticae selected with spiromesifen+abamectin (S+A) mixture formulation were demonstrated by biochemical and molecular methods. The susceptible (GSS) population of T. urticae, was selected with S+A and made resistant with increasing doses of the mixture formulation. The resistant population was divided into two, and selection pressure was terminated in one population which is named IR (Interrupt resistant). In the other population, the selection with S+A was continued and the population named IR2. Activities of some detoxification enzymes (esterase, glutathione-S-transferase (GST) and cytochrome P450) were investigated in the GSS and IR populations. The activity of esterase, GST and P450 enzymes were increased by 1.77, 2.57 and 2.58-fold, respectively, in the IR population compared to the GSS population. Also, investigation of synergistic effects with esterase inhibitor (TTP), GST inhibitor (DEM) and P450 inhibitor (PBO) in this population revealed that all three synergists showed significant synergistic effects in IR population. In molecular studies, when the population was screened for the presence of two previously identified glutamate channel mutations (G314D and G326E) by qPCR with TaqMan probes no mutations could be detected in glutamate channels. and the CTD domain of acetyl coenzyme-A carboxylase (ACCase). Furthermore, possible genetic mutations in the biotin carboxylase domain (BCD) and carboxyl transferase domain (CTD) of the ACCase target sites were determined by sequencing. Although a single amino acid mutation G37D in the BCD of the ACCase gene of the IR and IR2 populations was detected, its association with spiromesifen resistance was not confirmed. The results indicated that increased detoxification and possible target site mutation may be responsible for the S+A resistance in the IR and IR2 populations.

Genome-wide identification of poplar GSTU gene family and its PtrGSTU23 and PtrGSTU40 to improve salt tolerance in poplar

Glutathione S-transferases (GSTs) are abundant proteins encoded by a highly differentiated family of ancient genes. GSTs play an important role in plant cell detoxification and growth and development. However, their precise function in growth and response to abiotic stresses in poplar remains unclear. We have identified 81 GST genes from Populus trichocarpa, which have been categorized into 8 subfamilies. Among these subfamilies, the Tau subfamily stands out as the largest, consisting of 58 members. We isolated two Tau-like Glutathione S-transferases encoding genes, PtrGSTU23 and PtrGSTU40, and investigated the biological functions of these two genes in transgenic poplar to regulate salt tolerance in poplar. Under salt stress, reactive oxygen species (ROS) accumulate in plants, and overexpression of PtrGSTU23/40 in 84 K poplar (Populus alba × Populus glandulosa) could play a crucial role in regulating ROS scavenging by controlling the activity of plant GST enzyme. This regulation of GST enzyme activity enhanced the tolerance of poplar to salt stress. Ultimately, our findings contribute to the availability of genetic resources that can be utilized in the breeding of salt tolerance traits within fast-growing tree species.

Synthesis of Tungsten Oxide, Iron Oxide, and Copper-Doped Iron Oxide Nanocomposites and Evaluation of Their Mixing Effects with Cyromazine against Spodoptera littoralis (Boisduval).

Nanotechnology research is emerging as a cutting-edge technology, and nanocomposites have played a significant role in pest control. Therefore, the present study focuses on the synthesis of tungsten oxide (WO3), iron oxide (magnetic nanoparticle, MNP), and copper-doped iron oxide (MNP-Cu) nanocomposites and explores the different effects of their binary combinations with the insecticide cyromazine against Spodoptera littoralis. The synthesized nanoparticles were characterized by transmission electron microscopy, X-ray diffraction, Fourier-transform infrared spectroscopy, and Raman spectroscopy. None of the tested nanomaterials showed any toxicity against the different stages of S. littoralis. Larval and pupal durations increased with increasing cyromazine and nanomaterial concentrations. The longest larval and pupal durations were recorded under treatment with the mixture of cyromazine (100 mg/L) + MNP-Cu (500 mg/L); the survival periods were 23.5 and 15.6 days, compared with 10.8 and 7.7 days in the control, respectively. The percentages of pupation and adult emergence were negatively affected by all treatments. Among the 500 mg/L nanomaterial combinations, only cyromazine (25 mg/L) and WO3 (500 mg/L) resulted in adult emergence (at a rate of 27.3%). Some abnormalities in the S. littoralis stages were observed following treatment with the tested materials. The glutathione S-transferase and alpha-esterase enzyme activities in S. littoralis were significantly increased after treatment with cyromazine, followed by cyromazine/MNP-Cu combinations. The quantitative polymerase chain reaction (Q-PCR) data showed that all treated insects had a higher immune response than the control. Finally, mixes of nanocomposites and cyromazine may be suggested as viable alternatives for S. littoralis management.

Evaluation of the relationship among gene expressions and enzyme activities with antioxidant role and presenilin 1 expression in Alzheimer's disease.

It is known that oxidative stress originating from reactive oxygen species plays a role in the pathogenesis of Alzheimer's disease. In this study, the role of antioxidant status associated with oxidative stress in Alzheimer's disease was investigated. Peripheral blood samples were obtained from 28 healthy individuals (as control) and 28 Alzheimer's patients who met the National Institute of Neurological and Communicative Diseases and Stroke/Alzheimer's Disease and Related Disorders Association criteria. Catalase, glutathione S-transferase and paraoxonase 1 enzyme activities in blood plasma and glutathione S-transferase enzyme activities in erythrocytes were determined by spectrophotometer. Catalase, glutathione S-transferase and presenilin 1 gene expressions in leukocytes were determined using qRT-PCR. Data were analysed with SPSS one-way anova, a LSD post hoc test at p < 0.05. The activity of each enzyme was significantly reduced in Alzheimer's patients compared to control. The catalase gene expression level did not change compared to the control. Glutathione S-transferase and presenilin 1 gene expression levels were increased compared to the control.

Acute and Chronic Effects of the Antifouling Booster Biocide Diuron on the Harpacticoid Copepod Tigriopus japonicus Revealed through Multi-Biomarker Determination

Diuron, an additive biocide in antifouling paints, is widely employed to curtail the attachment of organisms on submerged surfaces in aquatic structures. Despite the detection of diuron in aquatic ecosystems, information regarding its acute and chronic impacts on aquatic invertebrates, particularly planktonic crustaceans, remains limited. In this study, we analyzed the acute (24 h) and chronic (12 days exposure across three generations) effects of different concentrations of diuron (1/10 of the no observed effect concentration (NOEC), the NOEC, and 1/10 of the lethal concentration 50% (LC50), derived from the 24 h acute toxicity value of 1152 μg L−1) on the harpacticoid copepod Tigriopus japonicus. The acute exposure experiment indicated that the 1/10 LC50 value of diuron significantly reduced the copepod’s feeding rate and acetylcholinesterase activity. In response to the 1/10 LC50 value, the intracellular reactive oxygen species were elevated alongside increased malondialdehyde levels, while the glutathione content was depleted. The enzymatic activities of glutathione S-transferase, catalase, and superoxide dismutase were significantly enhanced by the 1/10 LC50 value, suggesting a proactive role of the antioxidant defense system against oxidative stress. Conversely, the activities of glutathione peroxidase and glutathione reductase enzymes were increased at the NOEC value, while their values were reduced by the 1/10 LC50 value. Chronic exposure to 1/10 NOEC and NOEC values revealed the adverse multigenerational effects of diuron. The second generation exhibited the most sensitivity to diuron, with the NOEC value notably reducing survival rate, body length, nauplius-to-adult development, neonates per brood count, and extending the reproduction period. Taken together, our findings underscore that even sublethal diuron levels can adversely impact copepod populations across generations through intergenerational toxicity.

Effects of Arbutin on Potassium Bromate-Induced Erythrocyte Toxicity in Rats: Biochemical Evaluation of Some Metabolic Enzyme Activities In Vivo and In Vitro.

In the present study, the inhibitory effect of potassium bromate on the pentose phosphate pathway and intracellular antioxidant systems enzymes (glucose 6-phosphate dehydrogenase (G6PD), 6-phosphogluconate dehydrogenase (6PGD), glutathione reductase (GR), glutathione S-transferase (GST), and thioredoxin reductase (TrxR)) and the role of arbutin in ameliorating this inhibition were investigated. In the in vivo phase of the study, Wistar Albino rats (28 male adults) were randomly divided into four groups. Control (n = 7): isotonic serum (0.5 mL, i.p), potassium bromate group (n = 7): potassium bromate (100 mg/kg), arbutin group (n = 7): arbutin (i.p.) (50 mg/kg/day), potassium bromate + arbutin, and Group (n = 7): potassium bromate (100 mg/kg) + arbutin (50 mg/kg/day) (i.p). The results of in vivo study showed that the activities of G6PD, 6PGD, GR, and TrxR enzymes were strongly inhibited in potassium bromate groups (p < 0.05). It was determined that GST enzyme activity decreased in the potassium bromate group, but this decrease was not statistically significant compared to the control group (p ⩾ 0.05). A statistically significant increase was found in G6PD, 6PGD, GST, and TrxR enzyme activities in the arbutin group compared to the control group (p < 0.05). The increase in GR enzyme activity was not statistically significant (p ⩾ 0.05). The potassium bromate + arbutin group's enzyme activity increased in comparison to the potassium bromate group and was discovered to be closer to the control group. It was found that potassium bromate inhibited the 6PGD enzyme obtained from rat erythrocyte tissues with IC50 = 346 μM value and Ki = 434.4 μM ± 6.1 value, and the inhibition was noncompetitive.

Unveiling the molecular mechanisms and developmental consequences of mercury (Hg) toxicity in zebrafish embryo-larvae: A comprehensive approach

Mercury (Hg) is a global contaminant affecting aquatic ecosystems' health. Chronic exposure to Hg has shown that the normal development of zebrafish embryo-larvae is affected. However, the molecular mechanisms behind the toxicity of Hg on fish embryonic development are still poorly understood. This work aimed to investigate the effects of Hg exposure on zebrafish embryo-larvae using a combined approach at individual (mortality, embryo development and locomotor behavior) and biochemical (neurotoxicity and oxidative stress enzymatic activities and protein phosphatase expression) levels. The Fish Embryo Toxicity assay followed the Organization for Economic Cooperation and Development Guideline 236 and used a concentration range between 13 and 401 μg Hg/L. Lethal and developmental endpoints were examined at 24, 48, 72 and 96 hpf. Biochemical markers, including Acetylcholinesterase (AChE), Catalase (CAT), Glutathione Reductase (GR), and Glutathione-S-Transferase (GST) activities and, for the first time, the expression of the protein phosphatase 1 gamma (PP1γ) was assessed after 24, 48, 72 and 96 h of exposure to 10 and 100 μg Hg/L. The behavioral effects of a sublethal range of Hg (from 0.8 to 13 μg Hg/L) were assessed using an automated video tracking system at 120 hpf. Several developmental abnormalities on zebrafish embryos and larvae, including pericardial edema, spin and tail deformities and reduced rate of consumption of the yolk sac, were found after exposure to Hg (LC50 at 96 hpf of 139 μg Hg/L) with EC50 values for total malformations ranging from 22 to 264 μg Hg/L. After 96 hpf, no significant effects were observed in the CAT and GR activities. However, an increase in the GST activity in a concentration and time-dependent manner was found, denoting possible stress-related adaptation of zebrafish embryos to deleterious effects of Hg exposure. The AchE activity showed a response pattern in line with the behavioral responses. At the lowest concentration tested, no significant effects were found for the AChE activity, whereas a decrease in AChE activity was observed at 100 μg Hg/L, suggesting that exposure to Hg induced neurotoxic effects in zebrafish embryos which in turn may explain the lack of equilibrium found in this study (EC50 at 96 hpf of 83 μg Hg/L). Moreover, a decrease in the PP1γ expression was found after 96 h of exposure to 10 and 100 μg Hg/L. Thus, we suggest that Hg may be an inhibitor of PP1γ in zebrafish embryos-larvae and thus, along with the alterations in the enzymatic activity of GST, explain some of the developmental malformations observed, as well as the lack of equilibrium. Hence, in this study, we propose the use of PP1 expression, in combination with apical and biochemical endpoints, as a precursor for assessing Hg's toxic mechanism on embryonic development.

The Effect of Pomegranate-Black Carrot Juice on Serum and Erythrocytes of Sedentary Subjects Exposed to Exhausting Exercise

Background. In this study, the effects of pomegranate-black carrot juice mixture on serum and erythrocytes of sedentary individuals who had exhaustion test were investigated. Methods. A total of 20 men voluntarily participated in the study. Blood samples were obtained from participants on three conditions. First, before the study, blood samples of participants were collected (baseline). Second, the same participants performed in the 20-meter shuttle run test for 1 week each day and were subjected to oxidative stress. Lastly, the same participants were given a mixture of pomegranate-black carrot juices (100 ml/100 ml) for a week, 45 minutes prior to the 20-meter shuttle run test, and the stress + supplement was performed. Blood samples were taken at the end of each process. Results. In the erythrocytes, while the oxidative stress condition malondialdehyde (MDA) level and carbonic anhydrase (CA) enzyme activity levels increased compared to the baseline, reduced glutathione (GSH) level, glutathione reductase (GR), and glutathione S-transferase (GST) enzyme activity levels decreased. In stress + supplement conditions, while GSH and GR levels increased according to oxidative stress conditions, CA and MDA levels decreased. While the lactate dehydrogenase (LDH) level of the oxidative stress condition increased compared to the baseline, the LDH level of the stress + supplement decreased compared to the oxidative stress condition. Conclusions. Our results showed that the level of oxidative stress in subjects exposed to the exhaustion test decreased with the mixture of pomegranate-black carrot juices.

The effects of carvacrol on development and gene expression profiles in Spodoptera frugiperda

The fall armyworm, Spodoptera frugiperda, is a highly polyphagous agricultural pest that is widely distributed around the world and causes severe crop yield loss. Carvacrol showed adverse effects on many pests, such as larval death and growth inhibition. While the effects of carvacrol on S. frugiperda larvae are not yet known. In this study, the effects of carvacrol on S. frugiperda, including larval growth inhibition and mortality induction, were observed. The detoxification and digestive enzyme activities of larvae with 1.0 and 2.0 g/kg carvacrol treatments were analyzed. Carvacrol boosted the enzyme activities of carboxylesterase (CarE) and glutathione S-transferase (GST) while decreasing the activities of α-amylase (AMS), lipase (LIP), and trypsin. A total of 3422 differentially expressed genes were identified in the larvae treated with 2.0 g/kg carvacrol, of which the DEGs involved in xenobiotic detoxification, food digestion, and insecticidal targets were further examined. These results suggest that carvacrol could regulate growth and development by affecting the process of food digestion, and exert its toxicity on the larvae through interaction with a variety of insecticidal targets. While the altered expressions of detoxification enzymes might be related to the detoxification and metabolism of carvacrol. Our findings offer a theoretical foundation for the use of carvacrol for S. frugiperda control in the field.

Determination of Constituents of Extract of Celtis tournefortii Lam. by LC-MS/MS, Investigation of Enzyme Inhibition, Antimicrobial and Anticancer Effects

Phytochemicals found in extracts obtained from plants are very important bioactive constituents. In this study, phytochemicals in extract content obtained from Celtis tournefortii .Lam. tree (CT) leaves were determined by a LC-MS method. The constituents with the major concentrations was found rutin (2479.89 µg ml-1), coumarin (1241.68 µg ml-1), biochanin A (1026.42 µg ml-1), shikimic acid (477.32 µg ml-1), chlorogenic acid (300.76 µg ml-1). The suppressive effects of CT extract on the growth of pathogenic strains were studied by microdilution method. It was observed that it caused suppression on the strains in the concentration range of 2.00-8.00 µg ml-1. The inhibition effects of the extract on acetyl cholinesterase and glutathione-S transferase enzyme activities were investigated, and 50% inhibitory values of enzyme activity were found to be 13.58 and 13.86, respectively. Using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay method, the cell viability suppressive effects of CT leaf extract were studied in healthy skin fibroblast cells as well as ovarian, colon and brain cancer cells. It was observed that they created a 42%, 4.27%, and 14.29% suppression in cells, respectively.

Extraction Potential of Lolium perenne L. (Perennial Rye Grass) for Metals in Landfill Soil: Its Tolerance and Defense Strategies

Landfill sites open and close frequently throughout the world, taking over a significant amount of land and leaving it contaminated and unavailable to the surrounding population for use. Different forms of remediation methods have been employed to rehabilitate contaminated land to a state that poses less of a threat to the environment. Phytoremediation is one of the remediation techniques that has proven to be effective, economical and easier to implement compared to other methods. The main aim of this study was to explore the potential use of Lolium perenne L. to remediate and restore metal-contaminated landfill soil and determine its stress tolerance mechanism(s). The metal uptake, determined using inductively coupled plasma-optical emission spectroscopy (ICP-OES) and inductively coupled plasma-mass spectroscopy (ICP-MS), revealed that Lolium perenne accumulate a higher amount of metals in the roots than in leaves, which was further confirmed by the translocation factor (TF) values of all of the metals that were below 1, ranging between 0.2 and 0.8, while Cu, Cr and Pb had a bioaccumulation factor (BCF) &gt; 1. This confirms that L. perenne is capable of absorbing metals into the root matrix but might restrict further movement into other parts of the plant as a defense mechanism against metal toxicity. In response to metal-induced stress, L. perenne displayed an increase in enzyme activity of superoxide dismutase, glutathione S-transferase, peroxidase and amylases in plants grown in landfill soil. Peroxidases displayed the highest level of enzyme activity, while total amylolytic activity had the most significant increase in activity over time. Although not a hyperaccumulator, L. perenne is a potential candidate for the phytoremediation of landfill soil and the phytostabilization of Cu, Cr and Pb.

Investigation of Effects of Some Metal Ions and Some Pesticides on Glutathione S-Transferase (GST) Enzyme Purified from Van Lake Fish (Chalcalburnus Tarichi) Kidney

Industrial and agricultural processes have brought about the pollution of aquatic systems, and this situation in the water had adverse effects on human health. In order to reduce these negative effects, all mammalian and aquatic species have a defense system. One of these antioxidant systems is the glutathione S-transferase enzyme group, which has detoxification activity against ROS produced by organic pollutants and heavy metals. In this study, the effects of some pesticides and heavy metal ions on the GST enzyme activity purified kidney tissue of the Lake Van fish (C. Tarichii) was analyzed. Firstly, the purification process was carried out as homogenate preparation and glutathione-agarose affinity technique. SDS-PAGE was carried out to check the enzyme purity. The enzyme was obtained in 89% yield (335-fold) with 27.8-specific activity , and kinetic constants was determined for the enzyme; Km for GSH substrate: 0.429 mM Vmax for GSH substrate: 0.207 EU/mL-1; Km for CDNB substrate: 0.276 mM, Vmax for CDNB substrate: 0.161EU/mL-1. Effects of Met-Hg, Fe3+ Cr3+ , Cu2+, Mg2+, Zn2+, atrazine, methomyl ,and dinicanozole were studied on the activity of the purified enzyme and the IC50 values were determined as 34.5 mM, 10 μM, 1.5 μM, 2.4 μM, 63 μM, 0.15 mM, 9.8 μM, 2.67 μM , and 1.3 μM, respectively.

A Cost-Effective Immobilization Method for MBP Fusion Proteins on Microtiter Plates Using a Gelatinized Starch-Agarose Mixture and Its Application for Convenient Protein-Protein Interaction Analysis.

The detection and quantification of protein-protein interactions (PPIs) is a crucial technique that often involves the use of recombinant proteins with fusion protein tags, such as maltose-binding protein (MBP) and glutathione-S-transferase (GST). In this study, we improved the cohesive and sticky properties of gelatinized starch by supplementing it with agarose, resulting in a harder gel that could coat the bottom of a microtiter plate. The resulting gelatinized starch/agarose mixture allowed for the efficient immobilization of MBP-tagged proteins on the coated plates, enabling the use of indirect ELISA-like PPI assays. By using the enzymatic activity of GST as an indicator, we succeeded in determining the dissociation constants between MBP-tagged and GST-tagged proteins on 96-well microtiter plates and a microplate reader without any expensive specialized equipment.

Changes in antioxidant enzymes and locomotor activity of yellow mealworm larvae fed the mycotoxin zearalenone supplemented diet

The larvae of the yellow mealworm Tenebrio molitor represent a new sustainable source of protein and nutrients for animal and human nutrition. To ensure safe insect-based foods, the risks of mycotoxins and other chemicals must be elucidated. Since oxidative stress is known to underlie many mycotoxin-induced disorders, the present work investigates the effects of the mycotoxin zearalenone (ZEA) on the responses of some oxidative stress biomarkers, superoxide dismutase (SOD), catalase (CAT), and glutathione S-transferase (GST) in the whole body of mealworm, as well as the effects on larval survival, body weight, and locomotor activity, and some aspects of mycotoxin accumulation. Larvae were fed artificially contaminated wheat bran containing approximately 0.1 mg/kg, 0.5 mg/kg, 2 mg/kg, and 5 mg/kg ZEA for two weeks. The results of the current study showed that ZEA-contaminated wheat bran at a concentration of 0.5 mg/kg was correlated with increased SOD, CAT, and GST enzyme activities and decreased locomotor activity. Higher concentrations of ZEA, i.e., 2 and 5 mg/kg caused enzymes and locomotor activity to return to control levels. The presence of ZEA in the diet for two weeks did not affect survival but resulted in lower weight gain in T. molitor larvae. The concentration of ZEA in the residual material was 21.1–37.6%, while in the larvae it accounted for 0.38–0.51% of the mycotoxin in the feed. The selected concentrations were in accordance with the EU limits for the presence of ZEA in food and with the levels found in naturally contaminated cereals. Our results suggest that ZEA at the tested concentration induces physiological, biochemical, and behavioral changes in larvae that could potentially serve as early markers of mycotoxin contamination.

The Comparative Toxicity, Biochemical and Physiological Impacts of Chlorantraniliprole and Indoxacarb on Mamestra brassicae (Lepidoptera: Noctuidae).

The cabbage moth, Mamestra brassicae, is a polyphagous pest that attacks several crops. Here, the sublethal and lethal effects of chlorantraniliprole and indoxacarb were investigated on the developmental stages, detoxification enzymes, reproductive activity, calling behavior, peripheral physiology, and pheromone titer of M. brasssicae. Methods: To assess pesticide effects, the second instar larvae were maintained for 24 h on a semi-artificial diet containing insecticides at their LC10, LC30, and LC50 concentrations. M. brassicae was more susceptible to chlorantraniliprole (LC50 = 0.35 mg/L) than indoxacarb (LC50 = 1.71 mg/L). A significantly increased developmental time was observed with both insecticides at all tested concentrations but decreases in pupation rate, pupal weight, and emergence were limited to the LC50 concentration. Reductions in both the total number of eggs laid per female and the egg viability were observed with both insecticides at their LC30 and LC50 concentrations. Both female calling activity and the sex pheromone (Z11-hexadecenyl acetate and hexadecenyl acetate) titer were significantly reduced by chlorantraniliprole in LC50 concentration. Antennal responses of female antennae to benzaldehyde and 3-octanone were significantly weaker than controls after exposure to the indoxocarb LC50 concentration. Significant reductions in the enzymatic activity of glutathione S-transferases, mixed-function oxidases, and carboxylesterases were observed in response to both insecticides.

Effects of cerium oxide on liver tissue in liver ischemia‑reperfusion injury in rats undergoing sevoflurane anesthesia.

During liver surgery and transplantation, periods of partial or total vascular occlusion are inevitable and result in ischemia-reperfusion (IR) injury. Nanomedicine uses the latest technological advancement, which has emerged from interdisciplinary efforts involving biomedical sciences, physics and engineering to protect and improve human health. Antioxidant nanoparticles are potential therapeutic agents. The present study investigated the effects of cerium oxide (Co) administration and sevoflurane anesthesia on liver tissue with IR injury. A total of 36 rats were randomly divided into control, Co, IR, IR-Sevoflurane (IRS), Co + IR and Co + IRS groups. In the IR, IRS and Co + IRS groups, hepatic IR was induced. Intraperitoneal Co was administered to the Co groups 30 min before ischemia. Sevoflurane was administered to the IRS and Co + IRS groups during IR injury. Liver tissue samples were examined under the light microscope by staining with hematoxylin and eosin. Thiobarbituric acid (TBARS) levels as well as catalase (CAT) and glutathione-S-transferase (GST) enzyme activity were evaluated in liver tissue samples. The IR group had considerably more hydropic degeneration, sinusoidal dilatation and parenchymal neutrophil infiltration than the Co, IRS, Co + IR and Co + IRS groups. CAT and GST enzyme activity were significantly higher in Co and Co + IR groups compared with the IR group. TBARS levels were significantly lower in Co, IRS, Co + IR and Co + IRS groups compared whit those in the IR group. Intraperitoneal injection of Co with sevoflurane decreased oxidative stress and damage to the liver.