Chlorella vulgaris algae ameliorates chlorpyrifos toxicity in Nile tilapia with special reference to antioxidant enzymes and Streptococcus agalactiae infection.

BACKGROUND: Chlorpyrifos (CPF) is a widely used pesticide in the production of plant crops. Despite rapid CPF biodegradation, fish were exposed to wastewater containing detectable residues. Recently, medicinal plants and algae were intensively used in aquaculture to replace antibiotics and ameliorate stress impacts. METHODS AND RESULTS: An indoor experiment was conducted to evaluate the deleterious impacts of CPF pollution on Nile tilapia health and the potential mitigation role of Chlorella vulgaris algae. Firstly, the median lethal concentration LC50 - 72 h of CPF was determined to be 85.8 µg /L in Nile tilapia (35.6 ± 0.5 g body weight) at a water temperature of 27.5 °C. Secondly, fish were exposed to 10% of LC50 - 72 h for six weeks, and tissue samples were collected and examined every two weeks. Also, Nile tilapia were experimentally infected with Streptococcus agalactiae. Exposed fish were immunosuppressed expressed with a decrease in gene expressions of interleukin (IL) 1ß, IL-10, and tumor necrosis factor (TNF)-α. Also, a decline was recorded in glutathione peroxidase (GPx), superoxide dismutase (SOD), and catalase (CAT) gene expression in the head kidney tissue. A high mortality rate (MR) of 100% was recorded in fish exposed to CPF for six weeks and challenged with S. agalactiae. Fish that received dietary C. vulgaris could restore gene expression cytokines and antioxidants compared to the control. After six weeks of CPF exposure, fish suffered from anemia as red blood cell count (RBCs), hemoglobin (Hb), and packed cell volume (PCV) significantly declined along with downregulation of serum total protein (TP), globulin (GLO), and albumin (ALB). Liver enzymes were significantly upregulated in fish exposed to CPF pollution, alanine aminotransferase (ALT) (42.5, 53.3, and 61.7 IU/L) and aspartate aminotransferase (AST) (30.1, 31.2, and 22.8) after 2, 4, and 6 weeks, respectively. On S. agalactiae challenge, high MR was recorded in Nile tilapia exposed to CPF (G3) 60%, 60%, and 100% in week 2, week 4, and week 6, and C. vulgaris provided a relative protection level (RPL) of 0, 14.29, and 20%, respectively. CONCLUSIONS: It was concluded that CPF pollution induces immunosuppressed status, oxidative stress, and anemic signs in Nile tilapia. In contrast, C. vulgaris at a 50 g/kg fish feed dose could partially ameliorate such withdrawals, restoring normal physiological parameters.

Pesticide-Induced Alterations in Locomotor Activity, Anxiety, and Depression-like Behavior Are Mediated through Oxidative Stress-Related Autophagy: A Persistent Developmental Study in Mice.

Chlorpyrifos (CPF), dichlorvos (DDV), and cypermethrin (CP), as commonly used pesticides, have been implicated in inducing neuropsychiatric disorders, such as anxiety, depression-like behaviors, and locomotor activity impairment. However, the exact molecular mechanisms of these adverse effects, particularly in both sexes and their next-generation effects, remain unclear. In this study, we conducted behavioral analysis, along with cellular assays (monodansylcadaverine staining) and molecular investigations (qRT-PCR and western blotting of mTOR, P62, and Beclin-1) to clear the potential role of autophagy in pesticide-induced behavioral alterations. For this purpose, 42 adult female and 21 male inbred ICR mice (F0) were distributed into seven groups. Maternal mice (F0) and 112 F1 offspring were exposed to 0.5 and 1 ppm of CPF, DDV, and CP through drinking water. F1 male and female animals were studied to assess the sex-specific effects of pesticides on brain tissue. Our findings revealed pronounced anxiogenic effects and impaired locomotor activity in mice. F1 males exposed to CPF (1 ppm) exhibited significantly elevated depression-like behaviors compared to other groups. Moreover, pesticide exposure reduced mTOR and P62 levels, while enhancing the Beclin-1 gene and protein expression. These changes in autophagy signaling pathways, coupled with oxidative and neurogenic damage in the cerebral cortex and hippocampus, potentially contribute to heightened locomotor activity, anxiety, and depression-like behaviors following pesticide exposure. This study underscores the substantial impact of pesticides on both physiological and behavioral aspects, emphasizing the necessity for comprehensive assessments and regulatory considerations for pesticide use. Additionally, the identification of sex-specific responses presents a crucial dimension for pharmaceutical sciences, highlighting the need for tailored therapeutic interventions and further research in this field.

Multi-biomarker approach to evaluate the toxicity of chlorpyrifos (active ingredient and a commercial formulation) on different stages of Biomphalaria straminea.

Biomphalaria straminea is a freshwater gastropod native to South America and used in toxicological assessments. Our aim was to estimate 48 h-LC50 and sub-chronic effects after the exposure to low concentrations of chlorpyrifos as commercial formulation (CF) and active ingredient (AI) on B. straminea adult, embryos and juveniles. Concentrations between 1 and 5000 µg L-1 were chosen for acute exposures and 0.1 and 1 µg L-1 for the sub-chronic one. After 14 days biochemical parameters, viability and sub-populations of hemocytes, reproductive parameters, embryotoxicity and offspring' survival were studied. Egg masses laid between day 12 and 14 were separated to continue the exposure and the embryos were examined daily. Offspring' survival and morphological changes were registered for 14 days after hatching. 48 h-LC50, NOEC and LOEC were similar between CF and AI, however the CF caused more sub-lethal effects. CF but not the AI decreased carboxylesterases, catalase and the proportion of hyalinocytes with respect to the total hemocytes, and increased superoxide dismutase and the % of granulocytes with pseudopods. Also CF caused embryotoxicity probably due to the increase of embryos' membrane permeability. Acetylcholinesterase, superoxide dismutase, hemocytes sub-populations, the time and rate of hatching and juveniles' survival were the most sensitive biomarkers. We emphasize the importance of the assessment of a battery of biomarkers as a useful tool for toxicity studies including reproduction parameters and immunological responses. Also, we highlight the relevance of incorporating the evaluation of formulations in order to not underestimate the effects of pesticides on the environment.

Exposure to chlorpyrifos interferes with intercellular communication in cumulus-oocyte complexes during porcine oocyte maturation.

Chlorpyrifos (CPF), a widely used organophosphorus pesticide (OP) to control pests has been verified reproductive toxicity on mammalian oocytes. However, limited information exists on its correlation with the dysfunction of the intercellular communication in cumulus-oocyte complexes (COCs). Herein, our study utilized porcine COCs as models to directly address the latent impact of CPF on the communication between cumulus cells (CCs) and oocytes during in vitro maturation. The results demonstrated that CPF exposure decreased the rate of the first polar body (PB1) extrusion and blocked meiosis progression. Notably, the cumulus expansion of CPF-exposed COCs was suppressed significantly, accompanied by the down-regulated mRNA levels of cumulus expansion-related genes. Furthermore, the early apoptotic level was raised and the expression of BAX/BCL2 and cleaved caspase 3 was up-regulated in the CCs of CPF-exposed COCs (p < 0.05). Moreover, CPF exposure impaired mRNA levels of antioxidant enzyme-related genes, induced higher levels of reactive oxygen species (ROS) and reduced the levels of mitochondrial membrane potential (MMP) in CCs (p < 0.05). Additionally, the integrated optical density (IOD) rate (cumulus/oocyte) of calcein and the expression of connexin 43 (CX43) was increased in CPF treatment groups (p < 0.05). As well, CPF exposure reduced the expression levels of FSCN1, DAAM1 and MYO10, which resulted in a significant decrease in the number and fluorescence intensity of transzonal projections (TZPs). In conclusion, CPF inhibited the expansion of cumulus and caused oxidative stress and apoptosis as well as disturbed the function of gap junctions (GJs) and TZPs, which eventually resulted in the failure of oocyte maturation.

Molecular docking analysis of chlorpyrifos at the human α7-nAChR and its potential relationship with neurocytoxicity in SH-SY5Y cells.

The organophosphate insecticide chlorpyrifos (CPF), an acetylcholinesterase inhibitor, has raised serious concerns about human safety. Apart from inducing synaptic acetylcholine accumulation, CPF could also act at nicotinic acetylcholine receptors, like the α7-isoform (α7-nAChR), which could potentially be harmful to developing brains. Our aims were to use molecular docking to assess the binding interactions between CPF and α7-nAChR through, to test the neurocytotoxic and oxidative effects of very low concentrations of CPF on SH-SY5Y cells, and to hypothesize about the potential mediation of α7-nAChR. Docking analysis showed a significant binding affinity of CPH for the E fragment of the α7-nAChR (ΔGibbs: -5.63 to -6.85 Kcal/mol). According to the MTT- and Trypan Blue-based viability assays, commercial CPF showed concentration- and time-dependent neurotoxic effects at a concentration range (2.5-20 µM), ten-folds lower than those reported to have crucial effects for sheer CPF. A rise of the production of radical oxygen species (ROS) was seen at even lower concentrations (1-2.5 µM) of CPF after 24h. Notably, our docking analysis supports the antagonistic actions of CPF on α7-nAChR that were recently published. In conclusion, while α7-nAChR is responsible for neuronal survival and neurodevelopmental processes, its activity may also mediate the neurotoxicity of CPF.

Combined pesticides in field doses weaken honey bee (Apis cerana F.) flight ability and analyses of transcriptomics and metabolomics.

Imidacloprid, chlorpyrifos, and glyphosate rank among the most extensively employed pesticides worldwide. The effects of these pesticides and their combined on the flight capability of Apis cerana, and the potential underlying mechanisms remain uncertain. To investigate these effects, we carried out flight mill, transcriptome, and metabolome experiments. Our findings reveal that individual acute oral treatments with pesticides, specifically 20 µL of 10 ng/g imidacloprid (0.2 ng per bee), 30 ng/g chlorpyrifos (0.6 ng per bee), and 60 ng/g glyphosate (1.2 ng per bee), did not impact the flight capability of the bees. However, when bees were exposed to a combination of two or three pesticides, a notable reduction in flight duration and distance was observed. In the transcriptomic and metabolomic analyses, we identified 307 transcripts and 17 metabolites that exhibited differential expression following exposure to combined pesticides, primarily associated with metabolic pathways involved in energy regulation. Our results illuminate the intricate effects and potential hazards posed by combined pesticide exposures on bee behavior. These findings offer valuable insights into the synergistic potential of pesticide combinations and their capacity to impair bee behavior. Understanding these complex interactions is essential for comprehending the broader consequences of pesticide formulations on honey bee populations.

Biochemical and molecular-level effects of co-exposure to chlorpyrifos and lambda-cyhalothrin on the earthworm (Eisenia fetida).

Farmland soil organisms frequently encounter pesticide mixtures presented in their living environment. However, the underlying toxic mechanisms employed by soil animals to cope with such combined pollution have yet to be explored. This investigation aimed to reveal the changes in cellular and mRNA levels under chlorpyrifos (CPF) and lambda-cyhalothrin (LCT) co-exposures in earthworms (Eisenia fetida). Results exhibited that the combination of CPF and LCT triggered an acute synergistic influence on the animals. Most exposures resulted in significant alterations in the activities of total superoxide dismutase (T-SOD), copper/zinc superoxide dismutase (Cu/Zn-SOD), caspase 3, and carboxylesterase (CarE) compared to the basal level. Moreover, when exposed to chemical mixtures, the transcription levels of four genes [heat shock protein 70 (hsp70), gst, sod, and calreticulin (crt)] also displayed more pronounced changes compared with their individual exposures. These changes in determined parameters indicated the occurrence of oxidative stress, cell death, detoxification dysfunction, and endoplasmic reticulum damage after co-exposure to CPF and LCT in E. fetida. The comprehensive examination of mixture toxicities of CPF and LCT at different endpoints would help to understand the overall toxicity they cause to soil invertebrates. The augmented deleterious effect of these pesticides in a mixture suggested that mixture toxicity assessment was necessary for the safety evaluation and application of pesticide mixtures.

A comparative study on targeted gene expression in zebrafish and its gill cell line exposed to chlorpyrifos.

Chlorpyrifos (CPF) is an organophosphorus-based insecticide, which is known to pose a serious risk to aquatic animals. However, the mechanisms of CPF toxicity in animals still remain unclear. The present investigation aimed to compare the potential effects of CPF in zebrafish (Danio rerio) and its gill cell line (DrG cells). Based on the in vivo study, the LC50 was calculated as 18.03 µg/L and the chronic toxic effect of CPF was studied by exposing the fish to 1/10th (1.8 µg/L) and 1/5th (3.6 µg/L) of the LC50 value. Morphological changes were observed in fish and DrG cells which were exposed to sublethal concentrations of CPF. The results of MTT and NR assays showed significant decline in the survival of cells exposed to CPF at 96 h. The production of reactive oxygen species in DrG cells and expression levels of antioxidant markers, inflammatory response genes (cox2a and cox2b), cyp1a, proapoptotic genes (bax), antiapoptotic gene (bcl2), apoptotic genes (cas3 and p53), and neuroprotective gene (ache) were determined in vivo using zebrafish and in vitro using DrG cells after exposure to CPF. Significant changes were found in the ROS production (DrG cells) and in the expression of inflammatory, proapoptotic, and apoptotic genes. This study showed that DrG cells are potential alternative tools to replace the use of whole fish for toxicological studies.

Daily temperature fluctuation interacts with the mean temperature to increase the toxicity of a pyrethroid insecticide in a moth.

Climate change complicates ecotoxicology studies because species responses to pesticides depend on temperature. Classically illustrated by the effect of constant laboratory temperatures, a recent review revealed that the toxicity of pesticides is also often increased by daily temperature fluctuations. Here, we investigated the combined effects of daily temperature fluctuation and mean temperature on the toxicity of two insecticides in the moth Spodoptera littoralis. Our study tested the toxicity of chlorpyrifos and deltamethrin on larvae of six experimental groups that crossed three treatments of daily temperature fluctuations (0, 5 or 10 °C) and two treatments of mean temperatures (25 or 33 °C). We showed that daily temperature fluctuation increased larval mortality induced by chlorpyrifos and deltamethrin. However, the response differed between the organophosphorus insecticide chlorpyrifos and the pyrethroid insecticide deltamethrin. The increase in chlorpyrifos toxicity by daily temperature fluctuation did not differ between mean temperatures of 25 and 33 °C. Remarkably, the increase in deltamethrin toxicity by daily temperature fluctuation was dependent on the crossed effects of the amplitude of daily fluctuation and mean temperature. This increase in deltamethrin toxicity occurred with a daily fluctuation of only 5 °C for larvae reared at 25 °C and a daily fluctuation of 10 °C in larvae reared at 33 °C. To confidently quantify the responses of insecticide toxicity to temperature, future ecotoxicology studies will have to evaluate the generality of the interaction between the effects of daily temperature fluctuation and mean temperature.

Residues of chlorpyrifos in the environment induce resistance in Aedes albopictus by affecting its olfactory system and neurotoxicity.

Aedes albopictus, a virus-vector pest, is primarily controlled through the use of insecticides. In this study, we investigated the mechanisms of resistance in Ae. albopictus in terms of chlorpyrifos neurotoxicity to Ae. albopictus and its effects on the olfactory system. We assessed Ca2+-Mg2+-ATP levels, choline acetyltransferase (ChAT), Monoamine oxidase (MAO), odorant-binding proteins (OBPs), and olfactory receptor (OR7) gene expression in Ae. albopictus using various assays including Y-shaped tube experiments and DanioVision analysis to evaluate macromotor behavior. Our findings revealed that cumulative exposure to chlorpyrifos reduced the activity of neurotoxic Ca2+-Mg2+-ATPase and ChAT enzymes in Ae. albopictus to varying degrees, suppressed MAO-B enzyme expression, altered OBPs and OR7 expression patterns, as well as affected evasive response, physical mobility, and cumulative locomotor time under chlorpyrifos stress conditions for Ae. albopictus individuals. Consequently, these changes led to decreased feeding ability, reproductive capacity, and avoidance behavior towards natural enemies in Ae. albopictus populations exposed to chlorpyrifos stressors over time. To adapt to unfavorable living environments, Ae. albopictus may develop certain tolerance mechanisms against organophosphorus pesticides. This study provides valuable insights for guiding rational insecticide usage or dosage adjustments targeting the nervous system of Ae. albopictus.

Effect of chlorpyrifos-exposure on the expression levels of CYP genes in Daphnia magna and examination of a possibility that an up-regulated clan 3 CYP, CYP360A8, reacts with pesticides.

Daphnia magna is a test organism used for ecological risk assessments of pesticides, but little is known about the expression levels of cytochrome P450s (CYP)s and their changes after pesticide exposure in the less than 24-h-olds used for ecotoxicity tests. In this study, D. magna juveniles were exposed to 0.2 µg/L of chlorpyrifos under the conditions for acute immobilization test as specified by the OECD test guideline for 24 h, and then the gene expression was compared between the control and chlorpyrifos-exposure groups by RNA-sequencing analysis, with a focus on CYP genes. Among 38 CYP genes expressed in the control group, seven were significantly up-regulated while two were significantly down-regulated in the chlorpyrifos-exposure group. Although the sublethal concentration of chlorpyrifos did not change their expression levels so drastically (0.8 < fold change < 2.6), CY360A8 of D. magna (DmCYP360A8), which had been proposed to be responsible for metabolism of xenobiotics, was abundantly expressed in controls yet up-regulated by chlorpyrifos. Therefore, homology modeling of DmCYP360A8 was performed based on the amino acid sequence, and then molecular docking simulations with the insecticides that were indicated to be metabolized by CYPs in D. magna were conducted. The results indicated that DmCYP360A8 could contribute to the metabolism of diazinon and chlorfenapyr but not chlorpyrifos. These findings suggest that chlorpyrifos is probably detoxified by other CYP(s) including up-regulated and/or constitutively expressed one(s).

Chlorpyrifos impairs sperm parameters and number of Sertoli and Leydig cells in rats after exposure during the peripubertal period.

Chlorpyrifos is an organophosphate insecticide used to control pests in crops. Thus, humans are constantly exposed through ingestion of contaminated food or water, inhalation of contaminated air, and through the skin. The juvenile and peripubertal periods comprise a window of development of the reproductive system, sensitive to toxic agents. Considering the scarcity of data on exposure to the insecticide during these periods, the aim of this study was to evaluate the effects of chlorpyrifos on the testis during the juvenile and peripubertal periods. Thirty Wistar rats with an initial age of 25 days were distributed into 3 groups: control, which received corn oil (vehicle); CPS5, which received 5 mg/Kg b.w. of chlorpyrifos; and CPS15, which received 15 mg/Kg b.w. of chlorpyrifos. The groups were treated via gavage daily for 40 days and on the 41st experimental day, the animals were anesthetized and submitted to euthanasia to collect the organs. Blood was collected to obtain plasma and testosterone measurement. The testicles were removed, weighed and used for sperm count analyses, histopathological and morphometric analyzes and for oxidative stress analyses. Spermatozoa from the vas deferens were collected for analyzes of sperm morphology and acrosome integrity. The results showed that the two concentrations of chlorpyrifos caused a decrease in the number of Leydig and Sertoli cells and germ cells and increased the number of morphologically abnormal sperm and sperm with acrosomal damage. Furthermore, a decrease in lipid peroxidation was observed in the CPS5 and CPS15 groups, and a decrease in glutathione-S-transferase activity in the CPS5 group. We conclude that exposure to chlorpyrifos harms the daily production of sperm, as well as their quality, in addition to causing an imbalance in the oxidoreductive balance of the testicle.

Changes in thermal sensitivity of Rhinella arenarum tadpoles (Anura: Bufonidae) exposed to sublethal concentrations of different pesticide fractions (Lorsban® 75WG).

The intensive use of agrochemicals and the rapid increase of global temperatures have modified the thermal conditions of aquatic environments, thus increasing amphibians' vulnerability to global warming and positioning them at great risk. Commercial formulations of chlorpyrifos (COM) are the pesticides most widely used in agricultural activities, with a high toxic potential on amphibians. However, little is known about the separate effects of the active ingredient (CPF) and adjuvants (AD). We studied the thermal sensitivity at different concentrations and pesticide fractions in Rhinella arenarum tadpoles, on thermal tolerance limits (CTmax = Critical thermal maximum and CTmin = Critical thermal minimum), swimming speed (Ss), Optimum temperature (Top), and Thermal breadth 50 (B50). Our results demonstrate that the pesticide active ingredient, the adjuvants, and the commercial formulation of chlorpyrifos differentially impair the thermal sensitivity of R. arenarum tadpoles. The pesticide fractions affected the heat and the cold tolerance (CTmax and CTmin), depending on the concentrations they were exposed to. The locomotor performance (Ss, Top, and B50) of tadpoles also varied among fractions, treatments, and environmental temperatures. In the context of climate change, the outcomes presented are particularly relevant, as mean temperatures are increasing at unprecedented rates, which suggests that tadpoles inhabiting warming and polluted ponds are currently experiencing deleterious conditions. Considering that larval stages of amphibians are the most susceptible to changing environmental conditions and the alarming predictions about environmental temperatures in the future, it is likely that the synergism between high temperatures and pesticide exposure raise the threat of population deletions in the coming years.

Usefulness of oxidative stress biomarkers in native species for the biomonitoring of pesticide pollution in a shallow lake of the Austral Pampas, Argentina.

Pesticide contamination and its adverse effects on native freshwater species continue to be a worldwide major concern, mainly in developing countries. Passive biomonitoring of pesticide pollution in shallow lakes may be achieved by the simultaneous use of fish and wetland plants. Thus, the present study aimed to evaluate the occurrence of current-use pesticides in the surface water of a shallow lake of the Austral Pampas region (Buenos Aires Province, Argentina) surrounded by intensive agricultural activities and its relationship with a battery of biomarkers, including oxidative stress and genotoxicity, in two native species, the fish Oligosarcus jenynsii and the macrophyte Bidens laevis. A total of 26 pesticide residues were analyzed, and the main ones detected were glyphosate and its metabolite aminomethylphosphonic acid (AMPA), chlorpyrifos, and imidacloprid. In O. jenynsii, hydrogen peroxide (H2O2) content in the liver increased with chlorpyrifos occurrence, while malondialdehyde (MDA) levels in the brain and liver increased with the presence of both chlorpyrifos and glyphosate. In B. laevis, H2O2 and MDA levels in leaves and roots increased with AMPA occurrence. Also, leaf H2O2 contents and root MDA levels increased with chlorpyrifos concentration. In contrast, catalase and peroxidase activities in roots decreased with AMPA and chlorpyrifos occurrence. In both species, mainly H2O2 and MDA levels demonstrated their sensitivity to be used as biomarkers in the biomonitoring of current-use pesticide pollution in shallow lakes. Their use may provide information to plan strategies for environmental conservation by government institutions or decision-makers, and to assess the biota health status.

Response of the terrestrial isopod Porcellio scaber to lipopolysaccharide challenge after microplastic and insecticide exposure.

The exposure of organisms to microplastics could compromise their ability to cope with other environmental stressors, such as infections. In this context, we investigated the effects of a 14-day exposure of the terrestrial isopod Porcellio scaber to tire particles in soil (1.5 % w w-1 dry weight) on the organisms' response to a secondary exposure, i.e., injection of the bacterial endotoxin lipopolysaccharide. In addition, the insecticide chlorpyrifos (2 mg kg-1 dry weight) was tested as a positive control. The survival and immune response of P. scaber was assessed at the end of the 7- and 14-day primary exposure and two days after the secondary exposure, by analyzing selected haemolymph immune parameters (total haemocyte count, differential haemocyte count, and haemocyte viability). No change in survival was observed after primary exposure of P. scaber to tire particles or chlorpyrifos. However, primary exposure to chlorpyrifos triggered a strong activation of the immune response, which was not the case following exposure to the tire particles. Further injection of lipopolysaccharide into the body did not affect the survival of animals exposed to tire particles or chlorpyrifos, while a strong immunomodulatory change was observed, particularly with chlorpyrifos, and to some extent, tire particles. Based on these results, we conclude that exposure of P. scaber to tire particles or chlorpyrifos has no significant effect on the susceptibility of the organism to lipopolysaccharide in terms of their mortality, but primary exposure to an insecticide significantly modulates the immune response of the organisms to a second stressor. We discuss the "stress on stress" approach for testing low-toxic substances, such as microplastics, where an environmentally realistic exposure is followed by a secondary exposure.

Probing the toxic effect of chlorpyrifos as an environmental pollutant on the structure and biological activity of lysozyme under physiological conditions.

The pervasive use of pesticides like chlorpyrifos (CPY) has been associated with deleterious effects on biomolecules, posing significant risks to environmental integrity, public health, and overall ecosystem equilibrium. Accordingly, in this study, we investigated the potential binding interaction between the well-conserved enzyme, lysozyme (LSZ), and CPY through various spectroscopic techniques and molecular modeling. The UV-vis absorption and fluorescence experiments confirmed the complex formation and static quenching of the intrinsic fluorescence intensity. LSZ revealed a singular binding site for CPY, with binding constants around 105 M-1 across different temperature ranges. Analysis of thermodynamic parameters showed the spontaneous nature of the complexation process, while also revealing the pivotal role of hydrophobic interactions in stabilizing the LSZ-CPY system. According to circular dichroism and Fourier transform infrared studies, CPY binding changed the secondary structure of LSZ by boosting α-helix presence and reducing the levels of ß-sheet and ß-turn content. Further, CPY decreased the stability and activity of LSZ. Computational docking delineated the specific and highly preferred binding site of CPY within the structure of LSZ. Molecular dynamic simulation indicated the enduring stability of the LSZ/CPY complex and revealed structural modifications in the LSZ after binding with CPY. This research provides a detailed understanding of the intermolecular dynamics between CPY and LSZ, concurrently elucidating the molecular-level implications for the potential hazards of pesticides in the natural environment.

Deciphering the impact of greenhouse pesticides on hepatic metabolism profile: Toxicity experiments on HepG2 cells using chlorpyrifos and emamectin benzoate.

Epidemiological evidence on the health effects of pesticide exposure among greenhouse workers is limited, and the mechanisms are lacking. Building upon our team's previous population study, we selected two pesticides, CPF and EB, with high detection rates, based on the theoretical foundation that the liver serves as a detoxifying organ, we constructed a toxicity model using HepG2 cells to investigate the impact of individual or combined pesticide exposure on the hepatic metabolism profile, attempting to identify targeted biomarkers. Our results showed that CPF and EB could significantly affect the survival rate of HepG2 cells and disrupt their metabolic profile. There were 117 metabolites interfered by CPF exposure, which mainly affected ABC transporter, biosynthesis of amino acids, center carbon metabolism in cancer, fatty acid biosynthesis and other pathways, 95 metabolites interfered by EB exposure, which mainly affected center carbon metabolism in cancer, HIF-1 signaling pathway, valine, leucine and isoleucine biosynthesis, fatty acid biosynthesis and other pathways. The cross analysis and further biological experiments confirmed that CPF and EB pesticide exposure may affect the HIF-1 signaling pathway and valine, leucine and isoleucine biosynthesis in HepG2 cells, providing reliable experimental evidence for the prevention and treatment of liver damage in greenhouse workers.

Influence of chlorpyrifos and endosulfan and their metabolites on the virulence of Helicobacter pylori.

Organochlorine (OC) and organophosphorus (OP) pesticides such as chlorpyrifos (CPF) and endosulfan (ES) have been associated with a plethora of adverse health effects. Helicobacter pylori (H. pylori) infection can lead to gastrointestinal diseases by regulating several cellular processes. Thus, the current study focuses on the effect of the co-exposure to pesticides and H. pylori on gastric epithelial cells. We have used the in-silico approach to determine the interactive potential of pesticides and their metabolites with H. pylori-associated proteins. Further, various in-vitro methods depict the potential of ES in enhancing the virulence of H. pylori. Our results showed that ES along with H. pylori affects the mitochondrial dynamics, increases the transcript expression of mitochondrial fission genes, and lowers the mitochondrial membrane potential and biomass. They also promote inflammation and lower oxidative stress as predicted by ROS levels. Furthermore, co-exposure induces the multi-nucleated cells in gastric epithelial cells. In addition, ES along with H. pylori infection follows the extrinsic pathway for apoptotic signaling. H. pylori leads to the NF-κB activation which in turn advances the ß-catenin expression. The expression was further enhanced in the co-exposure condition and even more prominent in co-exposure with ES-conditioned media. Thus, our study demonstrated that pesticide and their metabolites enhance the pathogenicity of H. pylori infection.

Exposure to the environmental pollutant chlorpyrifos induces hepatic toxicity through activation of the JAK/STAT and MAPK pathways.

Chlorpyrifos (CHP) is an inexpensive highly effective organophosphate insecticide used worldwide. The unguided and excessive use of CHP by farmers has led to its significant accumulation in crops as well as contamination of water sources, causing health problems for humans and animals. Therefore, this study evaluated the toxicological effects of exposure to the environmental pollutant CHP at low, medium, and high (2.5, 5, and 10 mg·kg-1 BW) levels on rat liver by examining antioxidant levels, inflammation, and apoptosis based on the no observed adverse effect levels (NOAEL) (1 mg·kg-1 BW) and the CHP dose that does not cause any visual symptoms (5 mg·kg-1 BW). Furthermore, the involvement of the JAK/STAT and MAPK pathways in CHP-induced toxic effects was identified. The relationship between the expression levels of key proteins (p-JAK/JAK, p-STAT/STAT, p-JNK/JNK, p-P38/P38, and p-ERK/ERK) in the pathways and changes in the expression of markers associated with inflammation [inflammatory factors (IL-1ß, IL-6, IL-10, TNF-α), chemokines (GCLC and GCLM), and inflammatory signaling pathways (NF-кB, TLR2, TLR4, NLRP3, ASC, MyD88, IFN-γ, and iNOS)] and apoptosis [Bad, Bax, Bcl-2, Caspase3, Caspase9, and the cleavage substrate of Caspase PARP1] were also determined. The results suggest that CHP exposure disrupts liver function and activates the JAK/STAT and MAPK pathways via oxidative stress, exacerbating inflammation and apoptosis. Meanwhile, the JAK/STAT and MAPK pathways are involved in CHP-induced hepatotoxicity. These findings provide a novel direction for effective prevention and amelioration of health problems caused by CHP abuse in agriculture and households.

Chlorpyrifos enrichment enhances tolerance of Anabaena sp. PCC 7119 to dimethoate.

Organophosphorus (OP) insecticides are widely used for on-field pest control, constituting about 38% of global pesticide consumption. Insecticide tolerance has been recorded in microorganisms isolated from the contaminated soil. However, the cross-tolerance of laboratory-enriched cultures remains poorly understood. A chlorpyrifos tolerant (T) strain of Anabaena sp. PCC 7119 was developed through continuous enrichment of the wild strain (W). The cross-tolerance of the T strain to the OP insecticide dimethoate was assessed by measuring photosynthetic performance, key enzyme activities and degradation potential. The presence of dimethoate led to a significant reduction in the growth and pigment content of the W strain. In contrast, the T strain demonstrated improved growth and metabolic performance. Chl a and carotenoids were degraded faster than phycobiliproteins in both strains. The T strain exhibited superior photosynthetic performance, metabolic efficiency and photosystem functions, than of W strain, at both the tested dimethoate concentrations (100 and 200 µM). The treated T strain had more or less a normal OJIP fluorescence transient and bioenergetic functions, while the W strain showed a greater fluorescence rise at ≤ 300 µs indicating the inhibition of electron donation to PS II, and at 2 ms due to reduced electron release beyond QA. The T strain had significantly higher levels of esterase and phosphatases, further enhanced by insecticide treatment. Dimethoate degradation efficiency of the T strain was significantly higher than of the W strain. T strain also removed chlorpyrifos more efficiently than W strain at both the tested concentrations. The BCFs of both chlorpyrifos and dimethoate were lower in the T strain compared to the W strain. These findings suggest that the enriched strain exhibits promising results in withstanding dimethoate toxicity and could be explored for its potential as a bioremediating organism for OP degradation.