In silico attempt to reveal the link between cancer development and combined exposure to the maize herbicides: Glyphosate, nicosulfuron, S-metolachlor and terbuthylazine.

Pesticides are crucial for crop protection and have seen a 50 % increase in use in the last decade. Besides preventing significant crop losses their use has raised health concerns due to consumer exposure through residues in food and water. The toxicity data from individual components is often used to assess overall mixture toxicity, but uncertainty persists in understanding the behaviors of individual chemicals within these mixtures. Assessing the risk of pesticide mixture exposure remains challenging, potentially leading to overestimation or underestimation of toxicity. This study aims to establish a possible link between exposure to a herbicide mixture and genotoxic effects, focusing on cancer development. Our analysis was focused on four herbicides glyphosate, nicosulfuron, S-metolachlor and terbuthylazine. To determine the link between genes associated with cancer development due to exposure to herbicide mixture, a CTD database tools were used. Through the ToppFun tool molecular function and biological process associated with genes common to the disease of interest and selected herbicides were evaluated. And finally, GeneMANIA was used in order to analyze the function and interaction between common genes of herbicide mixture. Among the 7 common genes for herbicide mixture and cancer development coexpression characteristics were dominant at 65.41 %, 22.14 % of annotated genes shared the same pathway and 7.88 % showed co-localization. Among six target genes involved in genetic disease development co-expression was dominant at 87.34 %, colocalization at 8.03 % and shared protein domains at 4.52 %. Comprehensive molecular analyses, encompassing genomics, proteomics, and pathway analysis, are essential to unravel the specific mechanisms involved in the context of the studied mixture and its potential carcinogenic effects.

Triazine herbicide prometryn alters epoxide hydrolase activity and increases cytochrome P450 metabolites in murine livers via lipidomic profiling.

Oxylipins are a group of bioactive fatty acid metabolites generated via enzymatic oxygenation. They are notably involved in inflammation, pain, vascular tone, hemostasis, thrombosis, immunity, and coagulation. Oxylipins have become the focus of therapeutic intervention since they are implicated in many conditions, such as nonalcoholic fatty liver disease, cardiovascular disease, and aging. The liver plays a crucial role in lipid metabolism and distribution throughout the organism. Long-term exposure to pesticides is suspected to contribute to hepatic carcinogenesis via notable disruption of lipid metabolism. Prometryn is a methylthio-s-triazine herbicide used to control the growth of annual broadleaf and grass weeds in many cultivated plants. The amounts of prometryn documented in the environment, mainly waters, soil and plants used for human and domestic consumption are significantly high. Previous research revealed that prometryn decreased liver development during zebrafish embryogenesis. To understand the mechanisms by which prometryn could induce hepatotoxicity, the effect of prometryn (185 mg/kg every 48 h for seven days) was investigated on hepatic and plasma oxylipin levels in mice. Using an unbiased LC-MS/MS-based lipidomics approach, prometryn was found to alter oxylipins metabolites that are mainly derived from cytochrome P450 (CYP) and lipoxygenase (LOX) in both mice liver and plasma. Lipidomic analysis revealed that the hepatotoxic effects of prometryn are associated with increased epoxide hydrolase (EH) products, increased sEH and mEH enzymatic activities, and induction of oxidative stress. Furthermore, 9-HODE and 13-HODE levels were significantly increased in prometryn treated mice liver, suggesting increased levels of oxidation products. Together, these results support that sEH may be an important component of pesticide-induced liver toxicity.

Acute and chronic effects of the antifouling booster biocide Irgarol 1051 on the water flea Moina macrocopa revealed by multi-biomarker determination.

Irgarol 1051 is an herbicide extensively utilized in antifouling paint due to its ability to inhibit photosynthesis. Irgarol and its photodegradation products are highly persistent in waters and sediments, although they are present in low concentrations. However, our understanding of the harmful effects of Irgarol on non-target organisms remains limited. In this study, we assessed the effects of acute (24 h) and chronic (14 days across three generations) exposure to different concentrations (including the 1/10 NOEC, NOEC, and 1/10 LC50 calculated from the 24-h acute toxicity test) of Irgarol using the water flea Moina macrocopa. Acute exposure to 1/10 LC50 significantly decreased survival, feeding rate, thoracic limb activity, heart rate, and acetylcholinesterase activity. Elevated levels of intracellular reactive oxygen species and malondialdehyde, along with a significant increase in catalase and superoxide dismutase activity, suggested the induction of oxidative stress in response to 1/10 LC50. An initial boost in glutathione level and the enzymatic activities of glutathione peroxidase and glutathione reductase, followed by a plunge, implies some compromise in the antioxidant defense system. Upon chronic exposure to the NOEC value, both generations F1 and F2 displayed a significant decrease in survival rate, body length, number of neonates per brood, and delayed sexual maturation, suggesting maternal transfer of potential damage through generations. Taken together, Irgarol induced acute toxicity through physiological and cholinergic damage, accompanied by the induction of oxidative stress, in the water flea. Even its sub-lethal concentrations can induce detrimental effects across generations when consistently exposed.

An outbreak of renal failure in asian dogs due to s-triazine adulteration of pet food raw material: Analysis of unique, green kidney stones formed as a result.

Renoliths were removed at necropsy from dogs that had died from acute kidney injury in Asia in 2004 and submitted to our laboratories for analysis including elemental composition, mass spectrometry, and nuclear magnetic resonance spectroscopy. The presence of a mixed s-triazine matrix comprising melamine, cyanuric acid, and ammelide, but no detectable ammeline, was found in the stone samples we analyzed. The unusual and unique green coloration of these stones was determined to be due to the presence of biliverdin. The occurrence of these green stones distinguished the 2004 incident from another incident in 2007 in the USA and other reported cases. The presence of crystals was reported in renal tubules and collecting ducts in both outbreaks, but no stones were reported in the 2007 incident. This difference suggested a variation in the disease process caused by mixed s-triazine ingestion. Careful monitoring of food additives is warranted to prevent future problems in animals and humans.

Long-term exposure to prometryn damages the visual system and changes color preference of female zebrafish (Danio rerio).

Color vision, initiated from the cone photoreceptors, is essential for fish to obtain environmental information. Although the visual impairment of triazine herbicide prometryn has been reported, data on the effect of herbicide such as prometryn on natural color sensitivity of fish is scarce. Here, zebrafish were exposed to prometryn (0, 1, 10, and 100 µg/L) from 2 h post-fertilization to 160 days post-fertilization, to explore the effect and underlying mechanism of prometryn on color perception. The results indicated that 10 and 100 µg/L prometryn shortened the height of red-green cone cells, and down-regulated expression of genes involved in light transduction pathways (arr3a, pde6h) and visual cycle (lrata, rpe65a); meanwhile, 1 µg/L prometryn increased all-trans-retinoic acid levels in zebrafish eyes, and up-regulated the expression of genes involved in retinoid metabolism (rdh10b, aldh1a2, cyp26a1), finally leading to weakened red and green color perception of female zebrafish. This study first clarified how herbicide such as prometryn affected color vision of a freshwater fish after a long-term exposure from both morphological and functional disruption, and its hazard on color vision mediated-ecologically relevant tasks should not be ignored.

Unraveling the anti-androgenic mechanism of tris(2,3-dibromopropyl) isocyanurate (TBC) via the non-classical testosterone pathway and steroidogenesis: Potential human reproductive health implications.

The decline in male reproductive health, characterized by diminishing sperm count and testosterone levels, has raised concerns about environmental influences, particularly endocrine-disrupting chemicals (EDCs). Tris(2,3-dibromopropyl)isocyanurate (TBC), a novel brominated flame retardant widely used in electronics, textiles, and furniture, has emerged as a significant environmental contaminant with potential reproductive health implications. In this study, we investigated the molecular mechanisms underlying TBC-induced reproductive toxicity, particularly focusing on its impact on steroidogenesis and androgen signaling pathways using the GC-1 spg cell line as an in vitro model. Exposure of GC-1 spg cells to TBC, alone or in combination with testosterone or the anti-androgen flutamide resulted in decreased metabolic activity and increased lactate dehydrogenase release, indicating cytotoxic effects. Furthermore, TBC exposure led to a reduction in progesterone synthesis, while testosterone production remained unaffected. Interestingly, estradiol synthesis was diminished after TBC exposure, suggesting a disruption in steroid hormone balance critical for spermatogenesis. Mechanistic investigations revealed alterations in key proteins involved in the non-classical testosterone pathway and steroidogenesis. TBC exposure downregulated epidermal growth factor receptor (EGFR), protein kinase B (AKT), and phosphorylated cyclic AMP response element-binding protein (p-CREB), indicating suppression of non-classical androgen signaling. Additionally, decreased levels of steroidogenic acute regulatory protein (StAR) and 3-beta-hydroxysteroid dehydrogenase (HSD3ß1) suggest impaired steroidogenesis. Here we uncover the intricate molecular mechanisms underlying TBC-induced reproductive toxicity, highlighting its potential to disrupt steroid hormone synthesis and androgen signaling pathways. Understanding the adverse effects of TBC on male reproductive health is crucial for developing strategies to mitigate its environmental impact and safeguard human fertility.

Pollution level and ecological risk assessment of triazine herbicides in Laizhou Bay and derivation of seawater quality criteria.

Triazine herbicides are widely used in agriculture and have become common pollutants in marine environments. However, the spatiotemporal distribution characteristics and water quality criteria (WQC) of triazine herbicides are still unclear. This study found that triazine herbicides had a high detection rate of 100 % in surface seawater of Laizhou Bay, China, with average concentrations of 217.61, 225.13, 21.97, and 1296.72 ng/L in March, May, August, and October, respectively. Moreover, estuaries were important sources, and especially the Yellow River estuary exhibited the highest concentrations of 16,115.86 ng/L in October. The 10 triazine herbicides were detected in the sediments of Laizhou Bay, with a concentration ranging from 0.14-1.68 µg/kg. Atrazine and prometryn accounted for 33.41 %-59.10 % and 28.93 %-50.06 % of the total triazine herbicides in the seawater, and prometryn had the highest proportion (63.50 %) in the sediments. Correlation analysis revealed that triazine herbicides led to the loss of plankton biodiversity, which further decreased the dissolved oxygen. In addition, this study collected 45 acute toxicity data and 22 chronic toxicity data of atrazine, 16 acute toxicity data of prometryn, and supplemented with toxicity experiments of prometryn on marine organisms. Based on the toxicity database, the WQCs of atrazine and prometryn were derived using species sensitivity distribution. The overall risk probability of atrazine and prometryn were both less than 1.75 % in the Laizhou Bay, indicating an acceptable risk. This study not only clarified the pollution status and ecological risk of triazine herbicides, but also provided scientific basis for their environmental management standards.

Adsorption behavior of triazine pesticides on polystyrene microplastics aging with different processes in natural environment.

The presence of microplastics in the ecological environment, serving as carriers for other organic pollutants, has garnered widespread attention. These microplastics exposed in the environment may undergo various aging processes. However, there is still a lack of information regarding how these aged microplastics impact the environmental behavior and ecological toxicity of pollutants. In this study, we modified polystyrene microplastics by simulating the aging behavior that may occur under environmental exposure, and then explored the adsorption behavior and adsorption mechanism of microplastics before and after aging for typical triazine herbicides. It was shown that all aging treatments of polystyrene increased the adsorption of herbicides, the composite aged microplastics had the strongest adsorption capacity and the fastest adsorption rate, and of the three herbicides, metribuzin was adsorbed the most by microplastics. The interactions between microplastics and herbicides involved mechanisms such as hydrophobic interactions, surface adsorption, the effect of π-π interactions, and the formation of hydrogen bonds. Further studies confirmed that microplastics adsorbed with herbicides cause greater biotoxicity to E. coli. These findings elucidate the interactions between microplastics before and after aging and triazine herbicides. Acting as carriers, they alter the environmental behavior and ecological toxicity of organic pollutants, providing theoretical support for assessing the ecological risk of microplastics in water environments.

Non-target metabolomics approach for the investigation of the hidden effects induced by atrazine and its degradation products on plant metabolism.

Japanese radish (Raphanus sativus var. longipinnatus) plants grown under laboratory conditions were individually exposed to the same doses of atrazine (2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine, ATR) or its main degradation products: either 2-amino-4-chloro-6-isopropylamino-1,3,5-triazine (DEA) or 2-amino-4-chloro-6-ethylamino-1,3,5-triazine (DIA) or desethyl-desisopropyl-atrazine (DEDIA) or 4-(ethylamino)-2-hydroxy-6-(isopropylamino)-1,3,5-triazine (HA), respectively. One week after treatment in plants exposed to ATR, DIA, and DEA, their concentrations were 7.8 µg/g, 9.7 µg/g, and 14.5 µg/g, respectively, while those treated with DEDIA and HA did not contain these compounds. These results were correlated with plant amino acid profile obtained by suspect screening analysis and metabolomic "fingerprint" based on non-target analysis, obtained by liquid chromatography coupled with QTRAP triple quadrupole mass spectrometer. In all cases, both ATR and its by-products were found to interfere with the plant's amino acid profile and modify its metabolic "fingerprint". Therefore, we proved that the non-target metabolomics approach is an effective tool for investigating the hidden effects of pesticides and their transformation products, which is particularly important as these compounds may reduce the quality of edible plants.

Evaluation of sub-chronic toxicity of melamine via systematic or oral delivery in adult zebrafish based on behavioral endpoints.

Melamine-tainted products have been found in the market and raised issues about food safety. Recent studies done in rodents and humans demonstrated the toxicities of melamine, especially in causing kidney damage and bladder stone formation. However, very few studies assessed its behavior toxicity in organisms, including fish. Therefore, in this study, the researchers aim to determine whether sub-chronic exposure to melamine via oral and systematic administration could induce behavioral abnormality in zebrafish. After 14 days of systematic exposure to melamine at doses of 0.1 and 10 ppm levels, zebrafish were subjected to multiple behavioral assays. Results from both exposure routes showed that melamine indeed slightly increased fish locomotion and altered their exploratory behaviors in the novel tank assay. Furthermore, tightened shoaling formation was also displayed by the treated fish in the waterborne exposure group. However, melamine exposure did not cause any obvious alterations in fish behaviors during other behavioral tests. In addition, in comparison with previously published data on the behavior toxicities of several solvents in zebrafish, our phenomic analysis suggests the relatively low behavior toxicities of melamine via either systematic exposure or oral administration to zebrafish compared to those solvents. Nevertheless, our data indicate that the potential neurotoxicity of chronic low-dose melamine should not be ignored.

Environmental exposure to melamine and its derivatives and kidney outcomes in children.

Melamine caused acute nephrotoxicity in a past food adulteration incident, but it is unclear whether and how widespread ambient exposure to melamine and related compounds might affect pediatric kidney health. We assessed cross-sectional associations between childhood exposure to melamine and its derivatives and biomarkers of kidney injury and health and explored potential heterogeneity by sex suggested by sex-dependent differences in renal physiology. We measured melamine and its derivatives ammeline, ammelide, and cyanuric acid (CYA) in spot urine samples collected from 192 children from an urban site (Seattle, WA) and 187 children from a rural site (Yakima, WA) aged 4-8 years in the Global Alliance to Prevent Prematurity and Stillbirth (GAPPS) Study. In addition, biomarkers of kidney injury were measured in the same urine samples, including albumin, total protein, KIM-1, NAG, NGAL, and EGF. We utilized linear regressions to examine associations between individual chemical exposures and kidney biomarkers. Interaction terms examined association modification by sex, as well as potential interactions between melamine and CYA. Despite comparable exposures, girls had higher levels of many kidney injury biomarkers compared to boys. A ten-fold higher melamine concentration was associated with a 18% (95% CI: 5.6%, 31%) higher EGF in the full sample, while ten-fold higher melamine was associated with a 76% (14.1%, 173%) higher KIM-1 in boys but not in girls (-10.1% (-40.6%, 36.1%), interaction p = 0.026). Melamine exhibited significant negative interactions with CYA in association with total protein and NAG that appeared to be specific to girls. Our results suggest possible associations between melamine exposure and markers of kidney injury that may be more pronounced in boys. These findings provide novel insights into melamine and related derivative compound health effects at low levels of exposure in children and emphasize the role of sex in mediating the relationship between nephrotoxicant exposure and kidney injury.

Triazine herbicide reduced the toxicity of the harmful dinoflagellate Karenia mikimotoi by impairing its photosynthetic systems.

Triazine herbicides are common contaminants in coastal waters, and they are recognized as inhibitors of photosystem II, causing significant hinderance to the growth and reproduction of phytoplankton. However, the influence of these herbicides on microalgal toxin production remains unclear. This study aimed to examine this relationship by conducting a comprehensive physiological and 4D label-free quantitative proteomic analysis on the harmful dinoflagellate Karenia mikimotoi in the presence of the triazine herbicide dipropetryn. The findings demonstrated a significant decrease in photosynthetic activity and pigment content, as well as reduced levels of unsaturated fatty acids, reactive oxygen species (ROS), and hemolytic toxins in K. mikimotoi when exposed to dipropetryn. The proteomic analysis revealed a down-regulation in proteins associated with photosynthesis, ROS response, and energy metabolism, such as fatty acid biosynthesis, chlorophyll metabolism, and nitrogen metabolism. In contrast, an up-regulation of proteins related to energy-producing processes, such as fatty acid ß-oxidation, glycolysis, and the tricarboxylic acid cycle, was observed. This study demonstrated that dipropetryn disrupts the photosynthetic systems of K. mikimotoi, resulting in a notable decrease in algal toxin production. These findings provide valuable insights into the underlying mechanisms of toxin production in toxigenic microalgae and explore the potential effect of herbicide pollution on harmful algal blooms in coastal environments.

Bioinformatics analysis of the potential mechanisms of Alzheimer's disease induced by exposure to combined triazine herbicides.

BACKGROUND: The development of Alzheimer's disease (AD) is promoted by a combination of genetic and environmental factors. Notably, combined exposure to triazine herbicides atrazine (ATR), simazine (SIM), and propazine (PRO) may promote the development of AD, but the mechanism is unknown. AIM: To study the molecular mechanism of AD induced by triazine herbicides. METHODS: Differentially expressed genes (DEGs) of AD patients and controls were identified. The intersectional targets of ATR, SIM, and PRO for possible associations with AD were screened through network pharmacology and used for gene ontology (GO) and Kyoto Encyclopaedia of Genes and Genomes (KEGG) enrichment analysis. The binding potentials between the core targets and herbicides were validated by molecular docking and molecular dynamics. RESULTS: A total of 1,062 DEGs were screened between the AD patients and controls, which identified 148 intersectional targets of herbicides causing AD that were screened by network pharmacology analysis. GO and KEGG enrichment analysis revealed that cell cycling and cellular senescence were important signalling pathways. Finally, the core targets EGFR, FN1, and TYMS were screened and validated by molecular docking and molecular dynamics. CONCLUSION: Our results suggest that combined exposure to triazine herbicides might promote the development of AD, thereby providing new insights for the prevention of AD.

New Heterocyclic Compounds from Oxazol-5(4H)-one and 1,2,4-Triazin-6(5H)-one Classes: Synthesis, Characterization and Toxicity Evaluation.

This paper describes the synthesis of new heterocycles from oxazol-5(4H)-one and 1,2,4-triazin-6(5H)-one classes containing a phenyl-/4-bromophenylsulfonylphenyl moiety. The oxazol-5(4H)-ones were obtained via condensation of 2-(4-(4-X-phenylsulfonyl)benzamido)acetic acids with benzaldehyde/4-fluorobenzaldehyde in acetic anhydride and in the presence of sodium acetate. The reaction of oxazolones with phenylhydrazine, in acetic acid and sodium acetate, yielded the corresponding 1,2,4-triazin-6(5H)-ones. The structures of the compounds were confirmed using spectral (FT-IR, 1H-NMR, 13C-NMR, MS) and elemental analysis. The toxicity of the compounds was evaluated on Daphnia magna Straus crustaceans and on the budding yeast Saccharomyces cerevisiae. The results indicate that both the heterocyclic nucleus and halogen atoms significantly influenced the toxicity against D. magna, with the oxazolones being less toxic than triazinones. The halogen-free oxazolone had the lowest toxicity, and the fluorine-containing triazinone exhibited the highest toxicity. The compounds showed low toxicity against yeast cells, apparently due to the activity of plasma membrane multidrug transporters Pdr5 and Snq2. The predictive analyses indicated an antiproliferative effect as the most probable biological action. The PASS prediction and CHEMBL similarity studies show evidence that the compounds could inhibit certain relevant oncological protein kinases. These results correlated with toxicity assays suggest that halogen-free oxazolone could be a good candidate for future anticancer investigations.

Multi-generation reproductive toxicity of RDX and the involved signal pathways in Caenorhabditis elegans.

As one of the most frequently used explosives, hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) can cause persistent pollution in the environment, leading to the potential ecological threat crossing the generations. In this study, we employed Caenorhabditis elegans to explore the toxic effects of RDX on the parental and offspring worms and the involved signaling pathways. Exposure up to 1000 ng/mL of RDX produced a significant increase in reactive oxygen species (ROS) production, germ cell apoptosis, and decrease in eggs laid. Various mutants were used to demonstrate the RDX-induced apoptosis signaling pathway, and the metabolism of RDX in the nematodes was found related to cytochrome P450 and GST through RNA sequencing. Exposure of parental worms to RDX produced significant reproductive toxicity in F1 and F2, but was recovered in F3 and F4. The transgenerational effects were associated with the decreased expression of met-2, spr-5, and set-2. Our findings revealed the signaling pathways related to the reproductive toxicity caused by RDX in C. elegans and their future generations, which provided the basis for further exploration of the ecological risks of energetic compounds in the environment.

Effects of melamine and cyanuric acid on placental and fetal development in rats.

Melamine or cyanuric acid alone has low toxicity, but combined exposure to melamine and cyanuric acid was reported to cause unexpected toxicological effects. This study investigated the potential effects and toxic mechanism of combined exposure to melamine and cyanuric acid on placental and fetal development in rats. Exposure to melamine and cyanuric acid caused maternal toxicity manifested by increased abnormal symptoms and decreased body weight gain. Developmental toxic effects included a decrease in placental and fetal weights with increased fetal deaths and post-implantation loss. Melamine and cyanuric acid induced oxidative stress in the developing placenta and fetus. The placentas from rats treated with melamine and cyanuric acid showed shortening of the placental layers with histological changes, decreased cell proliferation, increased apoptotic changes, and decreased insulin-like growth factor (IGF)/IGF-binding proteins (IGFBPs) and placental lactogen (PL) expression levels. Fetuses from melamine- and cyanuric acid-treated dams showed increased apoptotic changes and suppressed cellular proliferation in their livers and vertebrae. Consequently, combined exposure to melamine and cyanuric acid resulted in high levels of oxidative stress and impaired placental development associated with impairment of the IGF/IGFBP and PL systems, resulting in increased apoptotic changes and reduced fetal cell proliferation.

Gene Expression and Pathway Analysis in Rat Brain and Liver After Exposure to Royal Demolition Explosive (Hexahydro-1,3,5-Trinitro-1,3,5-Triazine).

The nitramine explosive, hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) is associated with acute and chronic toxicity in mammals and targets both the central nervous system and liver. After a single oral dose of RDX in male rats, the systemic distribution of RDX and the toxicodynamic response was measured using clinical chemistry and Affymetrix Rat Genome® 230 2.0 gene expression arrays, respectively. Nominal doses of 0, 9 and 36 mg/kg pure RDX were administered to animals followed by liver, cerebral cortex, and hippocampus gene expression analysis at 0, 3.5, 24, and 48 hours. RDX quickly entered the liver and brain, increasing up to 24 hours. For the 36 mg/kg dose, RDX was still measurable in liver and brain at 48 hours, but was non-detectible for the 9 mg/kg dose. At 3.5 hours, the time within which most convulsions reportedly occur after RDX ingestion, the hippocampus displayed the highest response for both gene expression and pathways, while the cortex was relatively non-responsive. The top 2 impacted pathways, primarily involved in neurotransmission, were the GABAergic and glutamatergic pathways. High numbers of genes also responded to RDX in the liver with P450 metabolism pathways significantly involved. Compared to the liver, the hippocampus displayed more consistent biological effects across dose and time with neurotransmission pathways predominating. Overall, based on gene expression data, RDX responses were high in both the hippocampus and liver, but were minimal in the cerebral cortex. These results identify the hippocampus as an important target for RDX based on gene expression.

Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) causes seizure activity in larval zebrafish via antagonism of γ-aminobutyric acid type A receptor α1ß2γ2.

Hexahydro-1,3,5-trinitro-1,3,5-triazine, or Royal Demolition Explosive (RDX), is a major component of plastic explosives such as C-4. Acute exposures from intentional or accidental ingestion are a documented clinical concern, especially among young male U.S. service members in the armed forces. When ingested in large enough quantity, RDX causes tonic-clonic seizures. Previous in silico and in vitro experiments predict that RDX causes seizures by inhibiting α1ß2γ2 γ-aminobutyric acid type A (GABAA) receptor-mediated chloride currents. To determine whether this mechanism translates in vivo, we established a larval zebrafish model of RDX-induced seizures. After a 3 h of exposure to 300 µM RDX, larval zebrafish exhibited a significant increase in motility in comparison to vehicle controls. Researchers blinded to experimental group manually scored a 20-min segment of video starting at 3.5 h post-exposure and found significant seizure behavior that correlated with automated seizure scores. Midazolam (MDZ), an nonselective GABAAR positive allosteric modulator (PAM), and a combination of Zolpidem (α1 selective PAM) and compound 2-261 (ß2/3-selective PAM) were effective in mitigating RDX-triggered behavioral and electrographic seizures. These findings confirm that RDX induces seizure activity via inhibition of the α1ß2γ2 GABAAR and support the use of GABAAR-targeted anti-seizure drugs for the treatment of RDX-induced seizures.

Triazine Herbicides Risk Management Strategies on Environmental and Human Health Aspects Using In-Silico Methods.

As an effective herbicide, 1, 3, 5-Triazine herbicides (S-THs) are used widely in the pesticide market. However, due to their chemical properties, S-THs severely threaten the environment and human health (e.g., human lung cytotoxicity). In this study, molecular docking, Analytic Hierarchy Process-Technique for Order Preference by Similarity to the Ideal Solution (AHP-TOPSIS), and a three-dimensional quantitative structure-active relationship (3D-QSAR) model were used to design S-TH substitutes with high herbicidal functionality, high microbial degradability, and low human lung cytotoxicity. We discovered a substitute, Derivative-5, with excellent overall performance. Furthermore, Taguchi orthogonal experiments, full factorial design of experiments, and the molecular dynamics method were used to identify three chemicals (namely, the coexistence of aspartic acid, alanine, and glycine) that could promote the degradation of S-THs in maize cropping fields. Finally, density functional theory (DFT), Estimation Programs Interface (EPI), pharmacokinetic, and toxicokinetic methods were used to further verify the high microbial degradability, favorable aquatic environment, and human health friendliness of Derivative 5. This study provided a new direction for further optimizations of novel pesticide chemicals.

Scrutinizing the interaction between metribuzin with glutathione reductase 2 from Arabidopsis thaliana: insight into the molecular toxicity in agriculture.

As one of the triazine herbicides with widespread usage in agriculture, metribuzin exerted nonnegligible hazardous effects on plants via excessive accumulation of reactive oxygen species and destruction of antioxidant enzymes, but the underlying harmful mechanism of metribuzin-induced oxidative damage to plants has never been exploited. Here, Arabidopsis thaliana glutathione reductase 2 (AtGR2) was employed as the biomarker to evaluate the adverse impacts of metribuzin on plants. The fluorescence intensity of AtGR2 was decreased based on the static quenching mechanism with the prediction of a single binding site toward metribuzin, and the complex formation was presumed to be mainly impelled by hydrogen bonding and van der Waals forces from the negative ΔH and ΔS. In addition, the loosened and unfolded skeleton of AtGR2 along with the increased hydrophilicity around the tryptophan residues were investigated. Besides, the glutathione reductase activity of AtGR2 was also destroyed due to structural and conformational changes. At last, the severe inhibiting growth of Arabidopsis seedling roots was discovered under metribuzin exposure. Hence, the evaluation of the molecular interaction mechanism of AtGR2 with metribuzin will establish valuable assessments of the toxic effects of metribuzin on plants.