Three widely used pesticides and their mixtures induced cytotoxicity and apoptosis through the ROS-related caspase pathway in HepG2 cells

Elucidating the toxicity of methyl parathion, imazapic, isoxaflutole, and chlorantraniliprole on human hepatocarcinoma cells and bioinspired membranes

Pesticides have boosted agricultural productivity but pose significant risks to environmental and human health. The intensification of agriculture has driven widespread pesticide use, with 66 % of global consumption allocated to sugarcane, soybean and corn. Sugarcane, a major monoculture in Brazil, India, and China, has driven a 700 % increase in pesticide use in Brazil over the past 40 years. Commonly used pesticides in Brazilian sugarcane farming include methyl parathion (PM), imazapic (IM), isoxaflutole (IS), and chlorantraniliprole (CL). Despite regulatory efforts by governmental agencies worldwide, the long-term toxicity of these substances on human health remains insufficiently studied. This study evaluates the cytotoxicity of PM, IM, IS, and CL at concentrations regulated by governmental agencies in human hepatocarcinoma (HepG2) cells. Given the liver's role in metabolizing xenobiotics, it is especially vulnerable to pesticide-toxicity. MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) and LDH (lactate dehydrogenase release) assays, alongside confocal microscopy, showed reduced cell viability and impaired membrane integrity, with progressive toxicity (from 24 to 96 h), primarily impacting mitochondrial activity. Surface pressure-area (π-A) isotherms, compressibility (CS⁻¹), and atomic force microscopy (AFM) revealed distinct pesticide incorporation mechanisms into Langmuir monolayers of HepG2 lipid extracts, used as membrane models. The findings underscore the hepatotoxicity of PM, IM, IS, and CL, even at concentrations regulated by governmental agencies, emphasizing their potential human health hazards.

Toxic effects of deltamethrin on oxidative stress, behavioural, organosomatic indices and histopathological changes in Digitonthophagus gazella (Coleoptera: Scarabaeinae)

Pyrethroids pose a great concern to the declining population of dung beetles and the sustainability of ecosystem services. This study aimed to investigate the toxic effects of deltamethrin on Digitonthophagus gazella. First, the LC50 value (0.275 ppm) was determined, and sub-lethal concentrations (LD; low dose-0.014ppm, MD; medium dose-0.028ppm, and HD; high dose-0.055ppm) were assessed for physiological effects. The findings showed a significant dose and time dependent increase in fluorescence intensity (DCF-DA staining) and a decrease in antioxidant activity, including superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH). Furthermore, significant down regulation of cyp4g7, cyp6bq9, and cyp4q4 expression indicates enhanced oxidative stress. Additionally, a reduction in the organosomatic index, accompanied by histological changes in the brain, gut, and gonads, suggests potential functional disturbances. Overall, deltamethrin exposure had profound and irreversible pathological consequences on various vital organs and systems in D. gazella, affecting reproduction and nesting.

Autophagy is involved in the toxicity of the biocontrol agent GC16 against Tetranychus pueraricola (Acari: Tetranychidae) based on transcriptomic and proteomic analyses

BACKGROUND

GC16 is a novel pesticide with acaricidal properties against the spider mite Tetranychus pueraricola (Ehara & Gotoh). Its physiological mechanisms have been described previously, but its molecular mechanisms of action remain unclear. Thus, we aimed to explore the acaricidal mechanisms of GC16 through transcriptomic and proteomic analyses. The results were verified using transmission electron microscopy (TEM), immunofluorescence assay, and western blotting.

RESULTS

Transcriptomic and proteomic analyses revealed 2717 differentially expressed genes (DEGs) and 374 differentially expressed proteins (DEPs) between the GC16-treated and control mites. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis indicated that the DEGs and DEPs were enriched in the autophagy pathway. TEM showed that the number of autophagosomes and autolysosomes was higher in the GC16-treated mites than in the control mites. Immunofluorescence assay and western blot results consistently indicated that GC16 treatment significantly enhanced the relative expression of the autophagy protein LC3 in insect Sf9 cells. The intracellular calcium concentration in the GC16-treated Sf9 cells was 2.30 times higher than that in the control cells, suggesting that GC16 disrupted calcium homeostasis and potentially acted as a calcium-driven nerve agent.

CONCLUSIONS

Autophagy is involved in the toxicity of GC16 against T. pueraricola and may be activated by elevated Ca2+ levels. This study reveals the molecular insecticidal mechanisms of GC16 and provides rationale for the field application of GC16 to control pest mites.

Quantification of Pesticides and In Vitro Effects of Water-Soluble Fractions of Agricultural Soils in South Africa

Although agrochemicals protect crops and reduce losses, these chemicals can migrate to non-target environments via run-off and leaching following irrigation or heavy rainfall, where non-target organisms can be exposed to a mixture of water-soluble compounds. This study investigated whether the water-soluble fractions of selected agricultural soils from South Africa contain quantifiable concentrations of four commonly used pesticides, 2,4-dichlorophenoxyacetic acid (2,4-D), atrazine, dicamba and imidacloprid, and whether the aqueous extracts induce effects in vitro. Effects investigated included cytotoxicity using the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] cell viability assay; xenobiotic metabolism using the H4IIE-luc rat hepatoma cell line; and (anti-)androgenic and (anti-)oestrogenic effects were screened for with the human breast carcinoma cell lines MDA-kb2 and T47D-KBluc, respectively. Oxidative stress responses were measured in H4IIE-luc and human duodenum adenocarcinoma (HuTu-80) cells. All extracts of soil induced oxidative stress, while several samples caused moderate to severe cytotoxicity and/or anti-androgenic effects. The herbicide atrazine had the greatest frequency of detection (89%), followed by dicamba (84%), 2,4-D (74%) and imidacloprid (32%). Concentrations of atrazine [2.0 × 10-1 to 2.1 × 102 ng/g, dry mass (dm)] and the neonicotinoid insecticide, imidacloprid (2.0 × 101 to 9.7 × 101 ng/g, dm), exceeded international soil quality guidelines. Overall, there was no observable trend between the biological effects and pesticides quantified. Nonetheless, the findings of this study show that agricultural soils in South Africa can elicit effects in vitro and contain quantifiable concentrations of polar pesticides. These agrochemicals might pose risks to the health of humans and the environment, but more assessment is necessary to quantify such potential effects.

Beta-cypermethrin-induced stress response and ABC transporter-mediated detoxification in Tetrahymena thermophila

β-Cypermethrin (β-CYP), a synthetic pyrethroid pesticide, is widely used for insect management. However, it also affects non-target organisms and pollutes aquatic ecosystems. Tetrahymena thermophila, a unicellular ciliated protist found in fresh water, is in direct contact with aquatic environments and sensitive to environmental changes. The proliferation of T. thermophila was inhibited and the cellular morphology changed under β-CYP stress. The intracellular ROS level significantly increased, and SOD activity gradually rose with increasing β-CYP concentrations. Under 25 mg/L β-CYP stress, 687 genes were up-regulated, primarily enriched in the organic cyclic compound binding and heterocyclic compound binding pathways. These include 8 ATP-binding cassette transporters (ABC) family genes, 2 cytochrome P450 monooxygenase genes, and 2 glutathione peroxidase related genes. Among of them, ABCG14 knockdown affected cellular proliferation under β-CYP stress. In contrast, overexpression of ABCG14 enhanced cellular tolerance to β-CYP. The results demonstrated that Tetrahymena tolerates high β-CYP concentration stress through various detoxification mechanisms, with ABCG14 playing a crucial role in detoxification of β-CYP.

Recent advances in the toxicological effects of difenoconazole: A focus on toxic mechanisms in fish and mammals

The toxicological study of pesticides at sub-lethal and environment-relevant concentrations has become increasingly crucial for human and environmental health. Toxic mechanisms of agrochemicals contribute to discovering green pesticides, assessing the hazards of pesticides comprehensively, and supporting legitimate regulatory decisions. However, the toxicological effects of difenoconazole are not yet fully understood despite being frequently detected in fruits, vegetables, waters, and soils and posing hazards to humans and the environment. This lack of knowledge could lead to flawed risk assessment and administrative oversight. Thus, the review aimed to provide some investigation perspectives for clarifying the toxicological effects of difenoconazole by synthesizing the toxic data of difenoconazole on various organisms, such as bees, Daphnia magna, fish, earthworms, mammals, and plants and summarizing the toxicological mechanisms of difenoconazole, especially in fish and mammals from peer-reviewed publications. Evidence revealed that difenoconazole caused multiple toxicological effects, including developmental toxicity, reproductive toxicity, endocrine disruption effects, neurotoxicity, and transgenerational toxicity. The toxic mechanisms involved in metabolic disturbance, oxidative stress, inflammation, apoptosis, and autophagy by activating reactive oxygen species-mediated signaling pathways and mitochondrial apoptosis routes, disturbing amino acids, lipid, and nucleotide metabolism, and regulating gene transcription and expression in mammals and fish. Based on the review, further studies better focus on the toxic differences of difenoconazole stereoisomers, the toxicological effects of transformation products of difenoconazole, and the mechanism of action of difenoconazole on sex-specific endocrine disruption effects, intestinal damage, and gut dysbacteriosis for its hazard assessment and management synthetically.

Comprehensive multi-omics investigation of sub-chronic toxicity induced by Cadmium and Triazophos Co-exposure in hook snout carps (Opsariichthys bidens)

The coexistence of heavy metals and pesticides poses a critical challenge in agricultural ecosystems. Traditional toxicity assessments often focus only on the individual impacts of either pesticides or heavy metals. Here, the untargeted metabolomics and 16 S rRNA sequencing were used to assess the individual and combined effects of cadmium (Cd) and triazophos (TRI) on hook snout carps (Opsariichthys bidens). Cd caused much more serious impacts on hepatic metabolism and gut microbiota than those in TRI. Combined Cd and TRI exposure synergistically affected hepatic metabolism, causing mitochondrial dysfunction and even oxidative damage. Simultaneously, 16 S rRNA sequencing highlighted significant variations in the composition and abundance of gut microbiota. A noteworthy connection emerged between these distinct microbiota profiles and disruptions in energy metabolism, ultimately leading to disorders in metabolites. These findings enhanced the understanding of risks posed by heavy metals and pesticides, providing insights for better environmental risk assessments of aquatic organisms.

Enhanced stability and biocompatibility of HIPEs stabilized by cyclodextrin-metal organic frameworks with inclusion of resveratrol and soy protein isolate for β-carotene delivery

High internal phase Pickering emulsions (HIPEs) constitute a significant research domain within colloid interface chemistry, addressing the demand for robust emulsion systems across various applications. An innovative nanoparticle, synthesized from a cyclodextrin metal-organic framework encapsulated with a composite of resveratrol and soy isolate protein (RCS), was employed to fortify a high internal phase emulsion. The emulsion's three-dimensional printing capabilities, alongside the encapsulated delivery efficacy for β-carotene, were thoroughly examined. Cyclodextrin metal-organic frameworks (CD-MOFs), facilitated by cellulose nanofibrils, were synthesized to yield particles at the nanoscale, maintaining a remarkable 97.67 % cellular viability at an elevated concentration of 1000 μg/ml. The RCS nanoparticles demonstrated thermal stability and antioxidant capacities surpassing those of CD-MOF. The integration of soybean isolate protein augmented both the hydrophobicity (from 21.95 ± 0.64° to 59.15 ± 0.78°) and the interfacial tension (from 14.36 ± 0.46 mN/m to 5.34 ± 0.81 mN/m) of the CD-MOF encapsulated with resveratrol, thereby enhancing the RCS nanoparticles' adsorption at the oil-water interface with greater stability. The durability of the RCS-stabilized high internal phase emulsions was contingent upon the RCS concentration. Emulsions stabilized with 5 wt%-RCS exhibited optimal physical and chemical robustness, demonstrating superior performance in emulsion 3D printing and β-carotene encapsulation delivery. This investigation furnishes a novel perspective on the amalgamation of food customization and precision nutrition.

The antioxidant activity of polysaccharides from Armillaria gallica

The purpose of this study was to investigate the antioxidant activity of Armillaria gallica polysaccharides. It explored whether Armillaria gallica polysaccharides (AgP) could prevent HepG2 cells from H2O2-induced oxidative damage. The results demonstrated that HepG2 cells were significantly protected by AgP, and efficiently suppressed the production of reactive oxygen species (ROS) in HepG2 cells. Additionally, AgP significantly decreased the abnormal leakage of alanine aminotransferase (ALT) and lactate dehydrogenase (LDH) caused by H2O2, protecting cell membrane integrity. It was discovered that AgP was also found to regulate the activities of antioxidant enzymes, superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-PX), while reducing malondialdehyde (MDA), thus protecting cells from oxidative damage. According to the flow cytometry analysis and measurement of caspase-3, caspase-8, and caspase-9 activities, AgP could modulate apoptosis-related proteins and attenuate ROS-mediated cell apoptosis.

Pesticides exposure and compromised fitness in wild birds: Focusing on the reproductive endocrine disruption

Exposure of pesticides to wildlife species, especially on the aspect of endocrine disruption is of great concern. Wildlife species are more at risk to harmful exposures to the pesticides in their natural habitat through diet and several other means. Species at a higher tropic level in the food chain are more susceptible to the deleterious effects due to sequential biomagnifications of the pesticides/metabolites. Pesticides directly affect fitness of the species in the wild causing reproductive endocrine disruption impairing the hormones of the gonads and thyroid glands as reproduction is under the influence of cross regulations of these hormones. This review presents a comprehensive compilation of important literatures on the impact of the current use pesticides in disruption of both the hypothalamic-pituitary-gonadal and hypothalamic-pituitary-thyroid axes particularly in birds addressing impacts on the reproductive impairments and overall fitness. In addition to the epidemiological studies, laboratory investigations those provide supportive evidences of the probable mechanisms of disruption in the wild also have been incorporated in this review. To accurately predict the endocrine-disruption of the pesticides as well as to delineate the risk associated with potential cumulative effects, studies are to be more focused on the environmentally realistic exposure dose, mixture pesticide exposures and transgenerational effects. In addition, strategic screening/appropriate methodologies have to be developed to reveal the endocrine disruption potential of the contemporary use pesticides. Demand for adequate quantitative structure-activity relationships and insilico molecular docking studies for timely validation have been highlighted.

AFB1 Triggers Lipid Metabolism Disorders through the PI3K/Akt Pathway and Mediates Apoptosis Leading to Hepatotoxicity

As the most prevalent mycotoxin in agricultural products, aflatoxin B1 not only causes significant economic losses but also poses a substantial threat to human and animal health. AFB1 has been shown to increase the risk of hepatocellular carcinoma (HCC) but the underlying mechanism is not thoroughly researched. Here, we explored the toxicity mechanism of AFB1 on human hepatocytes following low-dose exposure based on transcriptomics and lipidomics. Apoptosis-related pathways were significantly upregulated after AFB1 exposure in all three hES-Hep, HepaRG, and HepG2 hepatogenic cell lines. By conducting a comparative analysis with the TCGA-LIHC database, four biomarkers (MTCH1, PPM1D, TP53I3, and UBC) shared by AFB1 and HCC were identified (hazard ratio > 1), which can be used to monitor the degree of AFB1-induced hepatotoxicity. Simultaneously, AFB1 induced abnormal metabolism of glycerolipids, sphingolipids, and glycerophospholipids in HepG2 cells (FDR < 0.05, impact > 0.1). Furthermore, combined analysis revealed strong regulatory effects between PIK3R1 and sphingolipids (correlation coefficient > 0.9), suggesting potential mediation by the phosphatidylinositol 3 kinase (PI3K) /protein kinase B (AKT) signaling pathway within mitochondria. This study revealed the dysregulation of lipid metabolism induced by AFB1 and found novel target genes associated with AFB-induced HCC development, providing reliable evidence for elucidating the hepatotoxicity of AFB as well as assessing food safety risks.

Nano-quercetin mitigates triazophos-induced testicular toxicity in rats by suppressing oxidative stress and apoptosis

The present study was designed to evaluate the testicular toxicity of triazophos in rats and to check the ameliorative effect of nano-quercetin against triazophos-induced toxicity. Nano-quercetin was synthesized from quercetin and characterized. Male Wistar rats were divided into seven groups. The control group received olive oil as a vehicle orally. The high-dose triazophos group and the low-dose triazophos group received 1/10th LD50 of triazophos (7.6 mg/kg) and 1/20th LD50 of triazophos (3.8 mg/kg), respectively. Two groups of animals were dosed with quercetin and nano-quercetin, both at 50 mg/kg body weight orally. The final two groups received high-dose triazophos with co-administration of quercetin and nano-quercetin, respectively. Triazophos disrupted the male endocrine axis by reducing the levels of steroidogenic enzymes 3-β-HSD and 17-β-HSD in testicular cells, further reducing FSH and testosterone. Also, triazophos increased the reactive oxygen species, induced lipid peroxidation, decreased the mitochondrial membrane potential, and elevated the number of apoptotic cells in rat testes. Nano-quercetin ameliorated the testicular oxidative stress and apoptotic and endocrine parameters more efficiently than quercetin. Besides, nano-quercetin alleviated the histopathological and biochemical alterations of triazophos. It is concluded that nano-quercetin has higher anti-oxidant efficacy than quercetin in protecting rats against triazophos-induced testicular toxicity.

Mechanisms of piperonyl butoxide cytotoxicity and its enhancement with imidacloprid and metals in Chinese hamster ovary cells

The widespread use of chemicals and the presence of chemical and metal residues in various foods, beverages, and other consumables have raised concerns about the potential for enhanced toxicity. This study assessed the cytotoxic effects of Piperonyl butoxide (PBO) and its enhancement by combination with major contamination chemicals including Imidacloprid and metals, using different cytotoxic and genotoxic assays in Chinese hamster ovary (CHO) cells. PBO exhibited elevated cytotoxic effects in poly (ADP-ribose) polymerase (PARP) deficient CHO mutants but not in Glutathione S-transferase deficient CHO mutants. PBO cytotoxicity was enhanced by PARP inhibitor, Olaparib. PBO cytotoxicity was also enhanced with co-exposure to Imidacloprid, Lead Chloride, or Sodium Selenite. PBO induces γH2AX foci formation and apoptosis. The induction of DNA damage markers was elevated with PARP deficiency and co-exposure to Imidacloprid, Lead Chloride, or Sodium Selenite. Moreover, PBO triggers to form etch pits on plastic surfaces. These results revealed novel mechanisms of PBO cytotoxicity associated with PARP and synergistic effects with other environmental pollutants. The toxicological mechanisms underlying exposure to various combinations at different concentrations, including concentrations below the permitted limit of intake or the level of concern, require further study.

Interactive transgenerational effects of parental co-exposure to prochloraz and chlorpyrifos: Disruption in multiple biological processes and induction of genotoxicity

The application of different types of pesticides can result in the coexistence of multiple pesticide residues in our food and the environment. This can have detrimental effects on the health of offspring across generations when parents are exposed to these pesticides. Therefore, it is imperative to understand the long-term effects that can be inherited by future generations when assessing the risks associated with pesticides. To study the genotoxic effects of commonly used pesticides, prochloraz (PRO) and chlorpyrifos (CHL), and assess whether their combined exposures have a different toxic effect, we modeled the transgenerational effects of parental (F0-generation) and/or offspring (F1-generation) exposures on zebrafish embryos in the F1-generation. Following the exposures, we proceeded to assess the impacts of these exposures on a range of biological processes in F1-generation zebrafish. Our results revealed that exposure to PRO and CHL altered multiple biological processes, such as inflammation, apoptosis, oxidative stress, and thyroid hormone synthesis, and detoxification system, providing molecular targets for subsequent studies on toxicity mechanisms. Notably, our study also found that the biological processes of F1-generation zebrafish embryos were altered even though they were not exposed to any pesticide when F0-generation zebrafish were exposed to PRO or CHL, suggesting potential genotoxicity. In conclusion, we provided in-vivo evidence that parental exposure to PRO and/or CHL can induce genotoxicity in the offspring. Moreover, we observed that the toxic effects resulting from the combined exposure were interactive, suggesting a potential synergistic impact on the offspring.

Use of Transcriptomics to Reveal the Joint Immunotoxicity Mechanism Initiated by Difenoconazole and Chlorothalonil in the Human Jurkat T-Cell Line

It is very important to evaluate the immunotoxicity and molecular mechanisms of pesticides. In this study, difenoconazole and chlorothalonil were evaluated for immunotoxicity by using the human Jurkat T-cell line, and the EC50 were 24.66 and 1.17 mg/L, respectively. The joint exposure of difenoconazole and chlorothalonil showed a synergistic effect at low concentrations (lower than 10.58 mg/L) but an antagonistic effect at high concentrations (higher than 10.58 mg/L). With joint exposure at a concentration of EC10, the proportion of late apoptotic cells was 2.26- and 2.91-fold higher than that with exposure to difenoconazole or chlorothalonil alone, respectively. A transcriptomics analysis indicated that the DEGs for single exposure are associated with immunodeficiency disease. Single exposure to chlorothalonil was mainly involved in cation transportation, extracellular matrix organization, and leukocyte cell adhesion. Single exposure to difenoconazole was mainly involved in nervous system development, muscle contraction, and immune system processes. However, when the joint exposure dose was EC10, the DEGs were mainly involved in the formation of cell structures, but the DEGs were mainly involved in cellular processes and metabolism when the joint exposure dose was EC25. The results indicated that the immunotoxicological mechanisms underlying joint exposure to difenoconazole and chlorothalonil are different under low and high doses.

Ginseng Stem-and-Leaf Saponins Mitigate Chlorpyrifos-Evoked Intestinal Toxicity In Vivo and In Vitro: Oxidative Stress, Inflammatory Response and Apoptosis

In recent years, the phenomenon of acute poisoning and organ damage caused by organophosphorus pesticides (OPs) has been a frequent occurrence. Chlorpyrifos (CPF) is one of the most widely used organophosphorus pesticides. The main active components of ginseng stems and leaves are total ginseng stem-and-leaf saponins (GSLSs), which have various biological effects, including anti-inflammatory, antioxidant and anti-tumor activities. We speculate that these could have great potential in the treatment of severe diseases and the relief of organophosphorus-pesticide-induced side effects; however, their mechanism of action is still unknown. At present, our work aims to evaluate the effects of GSLSs on the antioxidation of CPF in vivo and in vitro and their potential pharmacological mechanisms. Mice treated with CPF (5 mg/kg) showed severe intestinal mucosal injury, an elevated diamine oxidase (DAO) index, the decreased expression of occlusive protein-1 (ZO-1) and occlusive protein, an impaired intestinal mucosal oxidation system and intestinal villi relaxation. In addition, chlorpyrifos exposure significantly increased the contents of the inflammatory factor TNF-α and the oxidative-stress-related indicators superoxide dismutase (SOD), catalase (CAT), glutathione SH (GSH), glutathione peroxidase (GSH-PX), reactive oxygen species (ROS) and total antioxidant capacity (T-AOC); elevated the level of lipid peroxide malondialdehyde (MDA); reversed the expression of Bax and caspase; and activated NF-κB-related proteins. Interestingly, GSLS supplementation at doses of 100 and 200 mg/kg significantly reversed these changes after treatment. Similar results were observed in cultured RAW264.7 cells. Using flow cytometry, Hoechst staining showed that GSLSs (30 μg/mL, 60 μg/mL) could improve the cell injury and apoptosis caused by CPF and reduce the accumulation of ROS in cells. In conclusion, GSLSs play a protective role against CPF-induced enterotoxicity by inhibiting NF-κB-mediated apoptosis and alleviating oxidative stress and inflammation.

Cytomodulatory characteristics of Granulocyte-Macrophage Colony-Stimulating Factor (GM-CSF) against cypermethrin on skin fibroblast cells (HFF-1)

The hematopoietic factor granulocyte macrophage-colony stimulating factor (GM-CSF) has been identified via its capacity to promote bone marrow progenitors' development and differentiation into granulocytes and macrophages. Extensive pre-clinical research has established its promise as a critical therapeutic target in an assortment of inflammatory and autoimmune disorders. Despite the broad literature on GM-CSF as hematopoietic of stem cells, the cyto/geno protective aspects remain unknown. This study aimed to assess the cyto/geno protective possessions of GM-CSF on cypermethrin-induced cellular toxicity on HFF-1 cells as an in vitro model. In pre-treatment culture, cells were exposed to various GM-CSF concentrations (5, 10, 20, and 40 ng/mL) with cypermethrin at IC50 (5.13 ng/mL). Cytotoxicity, apoptotic rates, and genotoxicity were measured using the MTT, Annexin V-FITC/PI staining via flow-cytometry, and the comet assay. Cypermethrin at 5.13 ng/mL revealed cytotoxicity, apoptosis, oxidative stress, and genotoxicity while highlighting GM-CSF's protective properties on HFF-1. GM-CSF markedly attenuated cypermethrin-induced apoptotic cell death (early and late apoptotic rates). GM-CSF considerably regulated oxidative stress and genotoxicity by reducing the ROS and LPO levels, maintaining the status of GSH and activity of SOD, and suppressing genotoxicity in the comet assay parameters. Therefore, GM-CSF could be promising as an antioxidant, anti-apoptotic, genoprotective and cytomodulating agent.

In vitro exposure to triazoles used as fungicides impairs human granulosa cells steroidogenesis

Triazoles are the main components of fungicides used in conventional agriculture. Some data suggests that they may be endocrine disruptors. Here, we found five triazoles, prothioconazole, metconazole, difenoconazole, tetraconazole, and cyproconazole, in soil or water from the Centre-Val de Loire region of France. We then studied their effects from 0.001 µM to 1000 µM for 48 h on the steroidogenesis and cytotoxicity of ovarian cells from patients in this region and the human granulosa line KGN. In addition, the expression of the aryl hydrocarbon receptor (AHR) nuclear receptor in KGN cells was studied. Overall, all triazoles reduced the secretion of progesterone, estradiol, or both at doses that were non-cytotoxic but higher than those found in the environment. This was mainly associated, depending on the triazole, with a decrease in the expression of CYP51, STAR, CYP11A1, CYP19A1, or HSD3B proteins, or a combination thereof, in hGCs and KGN cells and an increase in AHR in KGN cells.

Difenoconazole Exposure Induces Retinoic Acid Signaling Dysregulation and Testicular Injury in Mice Testes

Difenoconazole (DFZ) is a broad-spectrum triazole fungicide that is widely utilized in agriculture. Although DFZ has been demonstrated to induce reproductive toxicity in aquatic species, its toxic effects on the mammalian reproductive system have yet to be fully elucidated. In vivo, male mice were administered 0, 20 or 40 mg/kg/d of DFZ via oral gavage for 35 days. Consequently, DFZ significantly decreased testicular organ coefficient, sperm count and testosterone levels, augmented sperm malformation rates, and elicited histopathological alterations in testes. TUNEL assay showed increased apoptosis in testis. Western blotting results suggested abnormally high expression of the sperm meiosis-associated proteins STRA8 and SCP3. The concentrations of retinoic acid (RA), retinaldehyde (RE), and retinol (ROL) were increased in the testicular tissues of DFZ-treated groups. The mRNA expression level of genes implicated in RA synthesis significantly increased while genes involved in RA catabolism significantly decreased. In vitro, DFZ reduced cell viability and increased RA, RE, and ROL levels in GC-2 cells. Transcriptome analysis revealed a significant enrichment of numerous terms associated with the RA pathway and apoptosis. The qPCR experiment verified the transcriptome results. In conclusion, our results indicate that DFZ exposure can disrupt RA signaling pathway homeostasis, and induce testicular injury in mice testes.

Triazole pesticides exposure impaired steroidogenesis associated to an increase in AHR and CAR expression in testis and altered sperm parameters in chicken

Since several decades, we observe the decline of various bird populations that could be partly linked to the agricultural intensification and the use of large amount of pesticides. Even if triazoles compounds are the most widely used fungicides, their effects on the reproductive parameters in birds are not clearly known. In the present study, we investigated the in vitro effects of 8 triazoles compounds alone (propiconazole (PP, from 0 to 10 µM), prothioconazole (PT), epoxiconazole (Epox), tetraconazole (TT), tebuconazole (TB), difenoconazole (Dif), cyproconazole (Cypro), metconazole (MC) (from 0 to 1 mM)) on the male chicken reproductive functions by using testis explants, primary Sertoli cells and sperm samples. In testis, all triazoles at the higher concentrations for 48 h inhibited lactate and testosterone secretion mostly in association with reduced expression of HSD3B and/or STAR mRNA levels. These data were also associated with increased expression of the nuclear receptors Aryl Hydrocarbon Receptor (AHR) and Constitutive Androstane Receptor (CAR) mRNA levels in testis and for all triazoles except for PP a reduction in Sertoli cell viability. When focusing on the sperm parameters, we demonstrated that most of the triazoles (MC, Epox, Dif, TB, TT and Cypro) at 0.1 or 1 mM for either 2, 12 or 24 min of exposure decreased sperm motility and velocity and increased the percentage of spermatozoa abnormal morphology. At the opposite, PP increased sperm motility in a dose dependent manner after 2 min of exposure whereas no significant effect was observed in response to PT whatever the dose and the time of exposure. Moreover, these effects were associated with an increase in the production of reactive oxygen species in spermatozoa. Taken together, most of the triazoles compounds impair testis steroidogenesis and semen parameters potentially through an increase in AHR and CAR expression and in oxidative stress, respectively.

Data Availability Statement

All the data will be available.

The role of pyrethroid derivatives in autophagy and apoptosis crosstalk signaling and potential risk for malignancies

Pyrethroids and its derivatives widespread and uncontrolled continuous use has influenced multiple deleterious effects resulting in as a potential risk factor causing damage to the organ systems. Allethrin and prallethrin are extensively used yet their influences on human primary cells are very limited or under reported. The potential mechanisms by which allethrin and prallethrin modulates human primary cells, especially the molecular mechanisms or interconnectivity of autophagy-apoptosis, their clinical relevance in human subjects or patients are not well defined. In this current study, we've furnished the evidence that both allethrin and prallethrin user samples significantly induced Ccl2 mRNA expression, increased amount of reactive oxygen intermediate, inhibited membrane bound enzymes and altered membrane fluidity. Pyrethroid derivative users had induced levels of lipid peroxidation and induced binding activities of transcription factors(tfs) like CEBP-β and NF-AT. Pyrethroid derivatives induced autophagy, elicited intracellular Ca2+ concentration, calcineurin and regulated proapoptotic genes, DAPK1, Bim. Our current study presumably comprises the initial investigation of a very new mechanism of pyrethroid derivatives-moderated programed cell death in various cell sets or types, like human primary cells where-in this is a late event, is documented. Hence, current research-study might be significant in the various pyrethroid derivatives-allied hematological-related cancers and immunosuppressant or auto-immune disorders. In the foremost instance, we present data stating that pyrethroid derivatives induces multiple cell signaling cascades, like CEBP-β, NF-AT, ERK and MAPK having a role in autophagy thereby; synchronously effectively impact on the apoptosis, therefore causing hematological tumors and toxic or immune related disorders.

Difenoconazole causes cardiotoxicity in common carp (Cyprinus carpio): Involvement of oxidative stress, inflammation, apoptosis and autophagy

Difenoconazole, a commonly used broad-spectrum triazole fungicide, is widely applied to fish culture in paddy fields. Due to its high chemical stability, low biodegradability, and easy transfer, difenoconazole persists in aquatic systems, raising public awareness of environmental threats. Difenoconazole causes cardiotoxicity in carp, however, the potential mechanisms of difenoconazole-induced cardiotoxicity remain unclear. Here, common carp were exposed to difenoconazole, and cardiotoxicity was evaluated by measuring the creatine kinase (CK) and the lactate dehydrogenase (LDH) in the serum. Cardiac pathological injury was determined by HE staining. The content and expression of oxidative stress indicators were detected using biochemical kits and qPCR analysis. Changes in inflammation-related cytokines were examined by qPCR. Apoptosis levels were assessed by TUNEL assay and qPCR. The occurrence of autophagy was measured by western blotting detection of autophagy flux LC3II/LC3I, and autophagy regulatory pathways were detected using qPCR. The results showed that difenoconazole exposure induced cardiotoxicity accompanied by obviously elevated LDH and CK levels and caused myocardial fibers to swell and inflammatory cells to increase. Elevated peroxide MDA and reduced transcriptional and activity levels of the antioxidant enzymes CAT, SOD and GSH-Px were dependent on the Nrf2/Keap-1 pathway. Moreover, the proinflammatory cytokines IL-1β, IL-6, and TNF-α were upregulated, iNOS activity was enhanced, whereas the anti-inflammatory cytokines TGF-β1 and IL-10 were downregulated after exposure to difenoconazole. Moreover, apoptosis was observed in the TUNEL assay and mediated through the p53/Bcl-2/Bax-Caspase-9 mitochondrial pathway. Furthermore, difenoconazole increased the autophagy markers LC3II, ATG5 and p62 and regulated them through the PI3K/AKT/mTOR pathway. Altogether, this study demonstrated that difenoconazole exposure caused common carp cardiotoxicity, which is regulated by oxidative stress, inflammation, apoptosis and autophagy, providing central data for toxicological risk assessment of difenoconazole in the ecological environment.

Difenoconazole disrupts the blood-brain barrier and results in neurotoxicity in carp by inhibiting the Nrf2 pathway mediated ROS accumulation

Excessive use of hard-to-degrade pesticides threatens the ecological health of aquatic systems. This study aimed to investigate difenoconazole (DFZ) residues in the environment induced neurotoxicity in carp and the underlying mechanisms. A total of thirty-six carps were divided into three groups and exposed to 0, 0.5, and 2.0 mg/L DFZ for 96 h, respectively. The alterations in behavior and blood-brain barrier (BBB) were examined, and potential mechanisms were explored using immunological assays and biochemical methods. The results showed that DFZ exposure caused behavioral freezing, reduced feeding, and neuronal necrosis in carp. Mechanistically, DFZ triggered ROS accumulation and destroyed the balance between oxidation and antioxidation with increased lipid peroxidation product MDA contents and reduced antioxidant enzymes SOD and CAT activities in the carp brain by inhibiting the NF-E2-related factor 2 (Nrf2) pathway. The activation of oxidative stress further reduced tight junction proteins and MMP levels, thereby destroying BBB and leading to DFZ leakage into the brain. Increased BBB permeability additionally led to DFZ activation of nuclear factor kappa-B signaling-mediated inflammatory cytokine storm, exacerbating neuroinflammation. Meanwhile, DFZ exposure activated mitochondria-associated apoptosis in the carp's brain by up-regulating Bcl-2 associated X protein, cleaved-caspase3, and cytochrome C and decreasing B-cell lymphoma-2 levels. Interestingly, the carp's brain initiated a protective autophagic response via the PI3K/AKT/TOR pathway intending to counteract the neurotoxicity of DFZ. Overall, we concluded that accumulation of DFZ at high concentrations in the aquatic systems disrupted the BBB and resulted in neurotoxicity in carp through inhibition of Nrf2 pathway-mediated ROS accumulation. This study provides a reference for monitoring DFZ residues in the environment and a new target for the treatment of DFZ-induced neurotoxicity in carp.

Cyclooxygenase-2 activates the free radical-mediated apoptosis of polymorphonuclear leukocytes in the maneb- and paraquat-intoxicated rats

Overproduction of free radicals and inflammation could lead to maneb (MB)- and paraquat (PQ)-induced toxicity in the polymorphonuclear leukocytes (PMNs). Cyclooxygenase-2 (COX-2), an inducible COX, is imperative in the pesticides-induced pathological alterations. However, its role in MB- and PQ-induced toxicity in the PMNs is not yet clearly deciphered. The current study explored the contribution of COX-2 in MB- and PQ-induced toxicity in the PMNs and the mechanism involved therein. Combined MB and PQ augmented the production of free radicals, lipid peroxides and activity of superoxide dismutase (SOD) in the rat PMNs. While combined MB and PQ elevated the expression of COX-2 protein, activation of nuclear factor-kappa B (NF-κB) and phosphorylation of c-Jun N-terminal kinase (JNK), release of mitochondrial cytochrome c and levels of procaspase-3/9 were attenuated in the PMNs. Celecoxib (CXB), a COX-2 inhibitor, ameliorated the combined MB and PQ-induced modulations in the PMNs. MB and PQ augmented the free radical generation, COX-2 protein expression, NF-κB activation and JNK phosphorylation and reduced the cell viability of cultured rat PMNs and human leukemic HL60. MB and PQ elevated mitochondrial cytochrome c release and poly (ADP-ribose) polymerase cleavage whilst procaspase-3/9 levels were attenuated in the cultured PMNs. MB and PQ also increased the levels of phosphorylated c-jun and caspase-3 activity in the HL60 cells. CXB; SP600125, a JNK-inhibitor and pyrrolidine dithiocarbamate (PDTC), a NF-κB inhibitor, rescued from MB and PQ-induced changes in the PMNs and HL60 cells. However, CXB offered the maximum protection among the three. The results show that COX-2 activates apoptosis in the PMNs following MB and PQ intoxication, which could be linked to NF-κB and JNK signaling.

Heterocyclic aromatic amines induce Neuro-2a cells cytotoxicity through oxidative stress-mediated mitochondria-dependent apoptotic signals

Heterocyclic aromatic amines (HAAs) are a class of hazardous compounds produced in food thermal processing. These compounds raise concerns because they have mutagenic and carcinogenic properties. However, the neurotoxicity of these compounds has received limited attention. Here, the toxic effects of three HAAs, i.e. 9H-pyrido[3,4-b]indole (Norharman), 1-methyl-9H-pyrido[3,4-b]indole (Harman), and 2-amino-3-methylimidazole[4,5-f]quinoline (IQ) were investigated in Neuro-2a cells model. The results showed that the survival rate of cells decreased in a dose-dependent manner and apoptosis occurred after exposure to the three HAAs for 24 h and 48 h. Their neurotoxicity was ranked as Harman > Norharman > IQ. Further, treatment of Harman, Norharman, or IQ at 50 and 100 μM for 48 h led to intracellular REDOX imbalance, which was manifested as increased ROS and malondialdehyde (MDA) levels, decreased GSH/GSSG ratio, and reduced SOD and CAT activities. Moreover, Norharman and Harman up-regulated the expression level of nuclear factor erythroid 2-related factor 2 (Nrf2), as well as the mRNA levels of Heme oxygenase-1 (HO-1) and NAD(P)H quinone oxidoredutase1 (NQO1), while IQ had no significant effect on the levels of Nrf2, HO-1, and NQO1. Additionally, Harman, Norharman, or IQ exposure significantly reduced mitochondrial membrane potential and intracellular ATP levels and up-regulated the levels of apoptosis-related genes and proteins. Collectively, our finding suggested that HAAs were neurotoxic, with mechanisms related to induction of oxidative stress and mitochondrial dysfunction.

DNA damage and cell apoptosis induced by fungicide difenoconazole in mouse mononuclear macrophage RAW264.7

Difenoconazole (DFC) is a typical triazole fungicide. Because of its effective bactericidal activity, it has been widely used in agricultural products such as fruits and vegetables. This study revealed the cytotoxic effect of fungicide DFC on mouse monocyte macrophage RAW264.7. The results showed that the IC₅₀ value of DFC on RAW264.7 cells was 37.08 μM (24 h). DFC can significantly inhibit the viability of RAW264.7 cells, induce DNA damage and enhance apoptosis. The established cytotoxicity test showed that DFC-induced DNA double strand breaks in RAW264.7 cells. DFC-treated cells showed typical morphological changes of apoptosis, including chromatin condensation and nuclear lysis. In addition, DFC can induce the release of Cyt c, promote the collapse of mitochondrial membrane potential and increase the Bax/Bcl-2 ratio in RAW264.7 cells. Through this research, people further understand the toxicity of DFC and provide a more scientific basis for its safety application and risk management.

Oxidative stress is involved in the activation of NF-κB signal pathway and immune inflammatory response in grass carp gill induced by cypermethrin and/or sulfamethoxazole

At present, the concentration of environmental pollutants, such as pesticides and antibiotics exposed in environment, especially in aquatic environment is increasing. Research on environmental pollutants has exploded in the last few years. However, studies on the combined effects of pesticides and antibiotics on fish are rare, especially the toxic damage to gill tissue is vague. In this paper, cypermethrin (CMN) and sulfamethoxazole (SMZ) were analyzed and found that there was a strong correlation between the pathways affected by the first 30 genes regulated by CMN and SMZ, respectively. Therefore, the toxic effects of CMN (0.651 μg L^-1) and/or SMZ (0.3 μg L^-1) on grass carp gill were studied in this paper. Histopathology, quantitative real-time PCR, and other methods were used to detect the tissue morphology, oxidative stress level, inflammation, and apoptosis-related indicators of the fish gills after exposure of 42 days. It was found that compared with the single exposure (CMN/SMZ) group, the combined exposure (MIX) group had a more pronounced oxidative stress index imbalance. At the same time, nuclear factor-κB (NF-κB) signal pathway was activated and immuno-inflammatory reaction appeared in MIX group. The expression of tumor necrosis factor (TNF-α) in the rising range is 2.94 times that of the C group, while the expression of interleukin 8 (IL-8) is as high as 32.67 times. This study reveals the harm of CMN and SMZ to fish, and provides a reference and basis for the rational use of pesticides and antibiotics.

Ginger reserves testicular spermatogenesis and steroidogenesis in difenoconazole-intoxicated rats by conducting oxidative stress, apoptosis and proliferation

Difenoconazole, a triazole fungicide, can induce reproductive toxicity in aquatic species, but the probable mechanisms of this hazard in mammals are not formally reported. Here, we have examined the possible ameliorative efficiency of the ginger aqueous extract against the reproductive toxicity of difenoconazole in male rats. Thirty-six animals were equally divided into six groups: control, ginger aqueous extract (50 mg/kg), difenoconazole (15 mg/kg), difenoconazole (30 mg/kg) and ginger co-treated with two doses of difenoconazole. Difenoconazole markedly decreased sperm count, motility and normality percentage, together with the Johnson score. Difenoconazole also significantly reduced serum testosterone, luteinizing hormone and follicle-stimulating hormone levels, as well as the activities of testicular steroidogenic acute regulatory protein and 17 β-hydroxysteroid dehydrogenases. Furthermore, difenoconazole brought a significant decrease in the testicular activity of catalase, but it increased the activity of glutathione peroxidase. Moreover, difenoconazole upregulated the testicular transcripts of Bax and caspase-3, increased Ki-67 immunoreactivity and induced histoarchitecture alterations plus DNA damage. Remarkably, ginger co-treatment preserved sperm toxicity, restored hormone profiles, increased steroidogenic activity and prevented oxidative injury-promoted testicular apoptosis. In conclusion, phenolic acids and flavonoids of ginger can reserve spermatogenesis and steroidogenesis in difenoconazole-intoxicated rats by improving testicular redox status, inhibiting apoptosis and refining proliferation capacity.

Insights into the effects of difenoconazole on the livers in male mice at the biochemical and transcriptomic levels

Difenoconazole (DFZ) is a broad-spectrum triazole fungicide, that is extensively used in agriculture. Studies have shown that residues of DFZ and other fungicides have toxic effects on nontarget organisms. However, its hepatoxicity in mammals remains unclear. Here, we characterized the toxic hepatic effects in male C57BL/6 mice exposed to 30 and 100 mg/kg bw DFZ for 14 and 56 days, respectively. The results revealed that DFZ could increase the relative liver weights, however, the relative fat and spleen weights decreased. More importantly, DFZ exposure changed the hepatic morphology and induced hepatic oxidative stress. Gene expression analysis suggested that DFZ could induce a glycolipid metabolism disorder. Moreover, hepatic transcriptomic analysis revealed the effects of DFZ exposure on the transcriptional levels of various genes, and enrichment analysis of differentially expressed genes (DEGs) showed that energy metabolism and immune-associated pathways were mainly affected. We validated the results from transcriptomic analysis and found that some key genes related to energy metabolism were affected. In addition, flow cytometry showed that the CD3+/CD4+ and CD3+ /CD8+ levels declined in the spleen of mice. Taken together, these findings combined with transcriptome analysis highlighted that DFZ caused different endpoints in the liver, which could provide more evidence for investigating the toxic effects of DFZ in mammals.

Sub-Chronic Difenoconazole Exposure Induced Gut Microbiota Dysbiosis in Mice

Difenoconazole (DIF) is a widely separated triazole fungicide in many countries. The excessive usage of DIF increases the high volume of residues in agriculture production and water bodies. Some previous studies demonstrated the toxic effects of DIF on non-target animals, however, there were still some gaps in the knowledge of the potential hazards of DIF to mammals and human health. Herein, 7-week-old male mice were exposed to 30 and 100 mg/kg/day DIF for 14 and 56 days. We observed that 56 days of DIF exposure decreased the colonic mucus expression of alcin blue-periodic acid-schiff (AB-PAS) stain and the immunochemical stain of muc2 protein. The transcript levels of mucin protein (muc1, muc2 and muc3) decreased significantly in the gut of mice followed 56 days of 100 mg/kg/day DIF exposure. In addition, the gut microbiota composition was also affected after 14 or 56 days of DIF exposure. Although the mucus expression after 14 days of DIF exposure only decreased slightly, the gut microbiota composition compared with the control group was changed significantly. Moreover, the DIF-30 and DIF-100 caused respectively different changes on the gut microbiota. The relative abundance of Bacteroidetes decreased significantly after 14 days and 56 days of DIF exposure. After 14 days of DIF exposure, there were 35 and 18 differential genera in the DIF-30 and DIF-100 group, respectively. There were 25 and 32 differential genera in the DIF-30 and DIF-100 group after 56 days of exposure, respectively. Meanwhile, the alpha diversity indexes, including observed species, Shannon, Simpson, Chao1 and ACE, in gut microbiota decreased significantly after 56 days of DIF exposure. Interestingly, the relative abundance of Akkermansia increased significantly after 56 days of 100 mg/kg/d DIF exposure. Although Akkermansia was considered as one probiotic, the phenomenon of dramatic Akkermansia increase with the decrease in gut microbiota diversity needed further discussion. These results provided some new insights on how DIF exposure impacts the mucus barrier and induces gut microbiota dysbiosis.

Fucoidan Modulated Oxidative Stress and Caspase-3 mRNA Expression Induced by Sulfoxaflor in the Brain of Mice

The current study aimed to investigate the role of fucoidan in the oxidative and apoptotic effects of sulfoxaflor, a neonicotinoid sulfoximine insecticide, in the brain of Swiss albino mice (Mus musculus). Sulfoxaflor and fucoidan were administered to mice at doses of 15 mg/kg/day (1/50 oral LD50) and 50 mg/kg/day, respectively, by oral gavage for 24 h or 7 days. The tGSH, TBARS and protein levels, and GPx, GR, and GST enzyme activities were determined by spectrophotometric methods. Caspase-3 gene expression level was determined by RT-PCR. Data analysis showed that brains of sulfoxaflor-treated mice exhibited higher TBARS levels; GPx, GR, and GST enzyme activities; and caspase-3 expression levels, as well as lower levels of tGSH. Co-administration of fucoidan and sulfoxaflor reduced the TBARS levels, increased tGSH levels, and increased GPx, GR, and GST enzyme activities. Fucoidan also decreased the sulfoxaflor-induced up-regulation of caspase-3 mRNA expression. Results of the present study showed that sulfoxaflor caused oxidative stress by inducing lipid peroxidation and altering GSH-dependent antioxidants in the brain of mice. In addition, sulfoxaflor may trigger apoptotic cell death shown by the up-regulation of caspase-3. Fucoidan treatment modulated all the aforementioned alterations in the brain of mice. It was concluded that fucoidan might have antioxidant effects that support the GSH-dependent antioxidant system and can play a modulator role in oxidative stress and caspase-3 expression in the brain of sulfoxaflor treated-mice.

The effect and mechanism of cypermethrin-induced hippocampal neurotoxicity as determined by network pharmacology analysis and experimental validation

Cypermethrin (CMN) is a widely used artificial synthetic pesticide that causes neurotoxicity in the hippocampus. However, the underlying toxicological targets and mechanisms remain unclear. In this study, network pharmacology analysis and in vitro models were integrated to investigate the effect and mechanism of CMN-induced hippocampal neurotoxicity. A total of 88 targets of CMN-induced hippocampal neurotoxicity were predicted. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes enrichment (KEGG) analyses suggested that these targets were related to multiple GO terms and signaling pathways. To further investigate underlying mechanism, the top 10 hub targets (Akt1, Tnf, Ptgs2, Casp3, Igf1, Sirt1, Jun, Cat, Il10, and Bcl2l1) were screened. Furthermore, cell viability and lactate dehydrogenase (LDH) assays demonstrated that CMN was toxic to HT22 cells in a time- and dose-dependent manner. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining revealed that treatment with CMN increased the proportion of apoptotic cells. In addition, the real-time quantitative polymerase chain reaction (RT-qPCR) results indicated that CMN altered the mRNA expression levels of most of the hub targets, with the exceptions of Igf1 and Jun. The results demonstrated that multiple targets and signaling pathways were involved in CMN-induced hippocampal neurotoxicity. These findings provided reference values for subsequent studies of the toxicological mechanism of CMN.

Toxic Feedback Loop Involving Iron, Reactive Oxygen Species, α-Synuclein and Neuromelanin in Parkinson's Disease and Intervention with Turmeric

Parkinson's disease (PD) is a movement disorder associated with severe loss of mainly dopaminergic neurons in the substantia nigra. Pathological hallmarks include Lewy bodies, and loss of neuromelanin, due to degeneration of neuromelanin-containing dopaminergic neurons. Despite being described over 200 years ago, the etiology of PD remains unknown. Here, we highlight the roles of reactive oxygen species (ROS), iron, alpha synuclein (α-syn) and neuromelanin in a toxic feedback loop culminating in neuronal death and spread of the disease. Dopaminergic neurons are particularly vulnerable due to decreased antioxidant concentration with aging, constant exposure to ROS and presence of neurotoxic compounds (e.g. ortho-quinones). ROS and iron increase each other's levels, creating a state of oxidative stress. α-Syn aggregation is influenced by ROS and iron but also increases ROS and iron via its induced mitochondrial dysfunction and ferric-reductase activity. Neuromelanin's binding affinity is affected by increased ROS and iron. Furthermore, during neuronal death, neuromelanin is degraded in the extracellular space, releasing its bound toxins. This cycle of events continues to neighboring neurons in the form of a toxic loop, causing PD pathology. The increase in ROS and iron may be an important target for therapies to disrupt this toxic loop, and therefore diets rich in certain 'nutraceuticals' may be beneficial. Turmeric is an attractive candidate, as it is known to have anti-oxidant and iron chelating properties. More studies are needed to test this theory and if validated, this would be a step towards development of lifestyle-based therapeutic modalities to complement existing PD treatments.

The enantioselective study of the toxicity effects of chiral acetochlor in HepG2 cells

Acetochlor is one of the most widely used chiral herbicides in the world, and it is usually produced and used as racemic form (Rac). The potential effects of acetochlor in human body are mainly induced by its residue in agriculture food. The direct target exposed is the liver in human body. However, the potential toxic and mechanism threat to human liver cells caused by chiral acetochlor has been rarely reported. The purpose of this study is to explore the potential mechanism of the toxicity caused by chiral acetochlor in HepG2 cells. The results revealed that acetochlor and its enantiomers could inhibit cell activity and cause DNA damage in HepG2 cells. The toxicity of Rac was higher than that of the two enantiomers, mainly derived from S configuration. The mechanism is through inducing decreased membrane potential (△Ψ), up-regulated Bax/BcL-2 expression, caused a cascade reaction, activated casepase-3 and casepase-9 and cleaved PARP, which maybe lead to cell death through apoptotic-signaling pathway in the end. These results illuminate that the genotoxic and cytotoxic risks of chiral acetochlor are major coming from S configuration. It provides a theoretical basis for the production of single pesticide to reduce the effects of human health.