Heterologous expression, biochemical characterization and prospects for insecticide biosensing potential of carboxylesterase Ha006a from Helicoverpa armigera.

Enzymes have attracted considerable scientific attention for their crucial role in detoxifying a wide range of harmful compounds. In today's global context, the extensive use of insecticides has emerged as a significant threat to the environment, sparking substantial concern. Insects, including economically important pests like Helicoverpa armigera, have developed resistance to conventional pest control methods through enzymes like carboxyl/cholinesterases. This study specifically focuses on a notable carboxyl/cholinesterase enzyme from Helicoverpa armigera (Ha006a), with the goal of harnessing its potential to combat environmental toxins. A total of six insecticides belonging to two different classes displayed varying inhibitory responses towards Ha006a, thereby rendering it effective in detoxifying a broader spectrum of insecticides. The significance of this research lies in discovering the bioremediation property of Ha006a, as it hydrolyzes synthetic pyrethroids (fenvalerate, λ-cyhalothrin and deltamethrin) and sequesters organophosphate (paraoxon ethyl, profenofos, and chlorpyrifos) insecticides. Additionally, the interaction studies between organophosphate insecticides and Ha006a helped in the fabrication of a novel electroanalytical sensor using a modified carbon paste electrode (MCPE). This sensor boasts impressive sensitivity, with detection limits of 0.019 µM, 0.15 µM, and 0.025 µM for paraoxon ethyl, profenofos, and chlorpyrifos, respectively. This study provides a comprehensive biochemical and biophysical characterization of the purified esterase Ha006a, showcasing its potential to remediate different classes of insecticides.

Lactic acid bacteria modulate the CncC pathway to enhance resistance to ß-cypermethrin in the oriental fruit fly.

The gut microbiota of insects has been shown to regulate host detoxification enzymes. However, the potential regulatory mechanisms involved remain unknown. Here, we report that gut bacteria increase insecticide resistance by activating the cap "n" collar isoform-C (CncC) pathway through enzymatically generated reactive oxygen species (ROS) in Bactrocera dorsalis. We demonstrated that Enterococcus casseliflavus and Lactococcus lactis, two lactic acid-producing bacteria, increase the resistance of B. dorsalis to ß-cypermethrin by regulating cytochrome P450 (P450) enzymes and α-glutathione S-transferase (GST) activities. These gut symbionts also induced the expression of CncC and muscle aponeurosis fibromatosis. BdCncC knockdown led to a decrease in resistance caused by gut bacteria. Ingestion of the ROS scavenger vitamin C in resistant strain affected the expression of BdCncC/BdKeap1/BdMafK, resulting in reduced P450 and GST activity. Furthermore, feeding with E. casseliflavus or L. lactis showed that BdNOX5 increased ROS production, and BdNOX5 knockdown affected the expression of the BdCncC/BdMafK pathway and detoxification genes. Moreover, lactic acid feeding activated the ROS-associated regulation of P450 and GST activity. Collectively, our findings indicate that symbiotic gut bacteria modulate intestinal detoxification pathways by affecting physiological biochemistry, thus providing new insights into the involvement of insect gut microbes in the development of insecticide resistance.

Late gestational exposure to fenvalerate impacts ovarian reserve in neonatal mice via YTHDF2-mediated P-body assembly.

Fenvalerate (FEN), a type II pyrethroid pesticide, finds extensive application in agriculture, graziery and public spaces for pest control, resulting in severe environmental pollution. As an environmental endocrine disruptor with estrogen-like activity, exposure to FEN exhibited adverse effects on ovarian functions. Additionally, the presence of the metabolite of FEN in women's urine shows a positive association with the risk of primary ovarian insufficiency (POI). In mammals, the primordial follicle pool established during the early life serves as a reservoir for storing all available oocytes throughout the female reproductive life. The initial size of the primordial follicle pool and the rate of its depletion affect the occurrence of POI. Nevertheless, there is very limited research about the impact of FEN exposure on primordial folliculogenesis. In this study, pregnant mice were orally administrated with 0.2, 2.0 and 20.0 mg/kg FEN from 16.5 to 18.5 days post-coitus (dpc). Ovaries exposed to FEN exhibited the presence of large germ-cell cysts that persist on 1 days post-parturition (1 dpp), followed by a significant reduction in the total number of oocytes in pups on 5 dpp. Moreover, the levels of m6A-RNA and its associated proteins METTL3 and YTHDF2 were significantly increased in the ovaries exposed to FEN. The increased YTHDF2 promoted the assembly of the cytoplasmic processing bodies (P-body) in the oocytes, accompanied with altered expression of transcripts. Additionally, when YTHDF2 was knocked-down in fetal ovary cultures, the primordial folliculogenesis disrupted by FEN exposure was effectively restored. Further, the female offspring exposed to FEN displayed ovarian dysfunctions reminiscent of POI in early adulthood, characterized by decreases in ovarian coefficient and female hormone levels. Therefore, the present study revealed that exposure to FEN during late pregnancy disrupted primordial folliculogenesis by YTHDF2-mediated P-body assembly, causing enduring adverse effects on female fertility.

The crosstalk between Toll and AMPK signaling pathways mediates growth inhibition of Eriocheir sinensis under deltamethrin stress.

Hepatopancreatic necrosis disease (HPND) broke out in 2015 in the Eriocheir sinensis aquaculture region of Xinghua, Jiangsu Province; however, the specific cause of HPND remains unclear. A correlation was found between HPND outbreak and the use of deltamethrin by farmers. In this study, E. sinensis specimens developed the clinical symptoms of HPND after 93 days of deltamethrin stress. The growth of E. sinensis with HPND was inhibited. Adenosine monophosphate-activated protein kinase (AMPK) is a central regulator of energy homeostasis, and its expression was up-regulated in the intestine of E. sinensis with HPND. Growth inhibitory genes (EsCabut, Es4E-BP, and EsCG6770) were also up-regulated in the intestine of E. sinensis with HPND. The expression levels of EsCabut, Es4E-BP, and EsCG6770 decreased after EsAMPK knockdown. Therefore, AMPK mediated the growth inhibition of E. sinensis with HPND. Further analysis indicated the presence of a crosstalk between the Toll and AMPK signaling pathways in E. sinensis with HPND. Multiple genes in the Toll signaling pathway were upregulated in E. sinensis under 93 days of deltamethrin stress. EsAMPK and its regulated growth inhibition genes were down-regulated after the knockdown of genes in the Toll pathway. In summary, the crosstalk between the Toll and AMPK signaling pathways mediates the growth inhibition of E. sinensis under deltamethrin stress.

Hepatoprotective and Antioxidant Effects of Nanopiperine against Cypermethrin via Mitigation of Oxidative Stress, Inflammations and Gene Expression Using qRT-PCR.

Cypermethrin (Cyp) is a pyrethroid that has been associated with the toxicity of various organs. The aim of our study was to evaluate the hepatoprotective and antioxidant activities of nano-piperine (NP) against Cyp toxicity. Cyp (50 mg/kg) was administered orally in all animals of groups III-VI for 15 days. Groups IV-VI each received three doses of NP (125, 250, and 500 µg/kg/day) for 10 days after receiving the Cyp dosage, which was given after 1 h. A rise in serum biomarkers (ALT, AST, ALP, total protein, and albumin), which are indicators of toxicity alongside anomalous oxidative stress indices (lipid peroxidation (LPO), glutathione (GSH), superoxide dismutase (SOD) and catalase), was detected. After Cyp treatment, we observed upregulated cytokines, caspase expression, and histological analysis that the showed distortion of cell shape. However, the administration of NP dramatically reversed all of the Cyp-induced alterations, inducing reductions in serum marker levels, stress level, the production of cytokines, and caspase expression. Additionally, all of the histopathological alterations were minimized to values that were comparable to normal levels. The present findings suggested that NP exhibits potent antioxidant and anti-inflammatory activities that can protect rats' livers against Cyp-induced liver damage through hepatoprotective activities.

CYP321A Subfamily P450s Contribute to the Detoxification of Phytochemicals and Pyrethroids in Spodoptera litura.

Although the induction of cytochrome P450 monooxygenases involved in insect detoxification has been well documented, the underlying regulatory mechanisms remain obscure. In Spodoptera litura, CYP321A subfamily members were effectively induced by exposure to flavone, xanthotoxin, curcumin, and λ-cyhalothrin, while knockdown of the CYP321A genes increased larval susceptibility to these xenobiotics. Homology modeling and molecular docking analyses showed that these four xenobiotics could stably bind to the CYP321A enzymes. Furthermore, two transcription factor genes, CncC and MafK, were significantly induced by the xenobiotics. Knockdown of CncC or MafK reduced the expression of four CYP321A genes and increased larval susceptibility to the xenobiotics. Dual-luciferase reporter assays showed that cotransfection of reporter plasmids carrying the CYP321A promoter with CncC and/or MafK-expressing constructs significantly magnified the promoter activity. These results indicate that the induction of CYP321A subfamily members conferring larval detoxification capability to xenobiotics is mediated by the activation of CncC and MafK.

Panax ginseng ameliorates hepatorenal oxidative alterations induced by commercially used cypermethrin in male rats: experimental and molecular docking approaches.

Cypermethrin (CYP) is a synthetic pyrethroid utilized as an insecticide in agriculture and various pest eradication programs. However, it induces numerous health hazards for animals and humans. Therefore, the current study used Panax ginseng root extract (ginseng) to reduce the hepatorenal damage caused by commercially used CYP. Thirty-two male Wistar albino rats were distributed into control, ginseng (300 mg/kg B.W/day), CYP (4.67 mg/kg B.W.), and Ginseng+CYP (rats received both CYP and ginseng). All treatments were administered orally for 30 consecutive days. Cypermethrin induced harmful effects on hepatic and renal tissues through a substantial decline in body weight in addition to a considerable increase in liver enzymes, functional renal markers, and cholesterol. Also, CYP significantly decreased acetylcholinesterase (AChE) activity and increased pro-inflammatory cytokines (interleukin-1ß (IL-1ß), IL-6, and tumor necrosis factor-α (TNF-α)). Moreover, a marked increase in malondialdehyde level with a significant drop in reduced glutathione level and total superoxide dismutase (T-SOD) and catalase (CAT) activities was reported in the CYP group in kidney and liver tissues. Additionally, CYP exhibited affinities to bind and inhibit AChE and antioxidant enzymes (T-SOD and CAT) in rats following the molecular docking modeling. The apparent hepatorenal oxidative damage was linked with obvious impairments in the liver and kidney histoarchitecture, immunohistochemical staining of B cell lymphoma-2 (Bcl-2), and caspase-3 proteins. Ginseng reduced CYP's oxidative alterations by repairing the metabolic functional markers, improving antioxidant status, reducing the inflammatory response, and enhancing the molecular docking evaluation. It also ameliorated the intensity of the histopathological alterations and improved the immunohistochemical staining of Bcl-2 and caspase-3 proteins in the liver and kidney tissues. Finally, concomitant oral administration of ginseng mitigated CYP-prompted hepatorenal damage through its antioxidant, anti-inflammatory, and anti-apoptotic potentials.

Identification and functional analysis of ABC transporter genes related to deltamethrin resistance in Culex pipiens pallens.

BACKGROUND: Pathogens that reproduce or develop in mosquitoes can transmit several diseases, endanger human health, and overwhelm health systems. Synthetic pyrethroids are the most widely used insecticides against adult mosquitoes, but their widespread use has led to resistance. The adenosine triphosphate (ATP)-binding cassette (ABC) transporters are involved in the resistance monitoring of insects, but their role and underlying mechanisms in insecticide resistance have not been fully elucidated. In the present study, we identified ABC transporter genes in Culex pipiens and investigated their role in the development of insecticide resistance. RESULTS: We identified 63 ABC transporter genes in Cx. pipiens and classified them as per the ABC transporter subfamilies. We also performed phylogenetic analysis. The knockdown rate of the mosquitoes orally fed with the ABC transporter inhibitor verapamil increased after deltamethrin treatment compared with that of the control group. Several genes from the ABCB, ABCC, and ABCG subfamilies were highly expressed in resistant mosquitoes. Immunofluorescence analysis revealed that ABCG6032427 was expressed in the head, chest, abdomen, wings, and legs, and the expression was the highest in the legs. Subsequently, knockdown of ABCG6032427 using RNA interference (RNAi) increased the sensitivity of the mosquitoes to deltamethrin, and scanning and transmission electron microscopy revealed that ABCG6032427 knockdown reduced cuticle thickness and the cuticle became loose and irregular. CONCLUSIONS: ABCG6032427 may modulate cuticle thickness and structure, thus play an important role in the development of deltamethrin resistance in mosquitoes. Thus, it could be a potential target for deltamethrin resistance management in Cx. pipiens. © 2023 Society of Chemical Industry.

Identification of 14 glutathione S-transferase genes from Lasioderma serricorne and characterization of LsGSTe1 involved in lambda-cyhalothrin detoxification.

In insects, glutathione S-transferases (GSTs) play a pivotal role in the detoxification of a wide range of pesticides. The cigarette beetle, Lasioderma serricorne, is an economically important pest insect of stored products. Recently, pyrethroid insecticides have been used to control this pest. However, little is known concerning the responses and functions of GSTs in L. serricorne under pyrethroid exposure. In this study, transcriptome sequencing was performed on L. serricorne, and a total of 14 GSTs were identified by retrieving the unigene dataset. Of these, 13 predicted GSTs fell into six cytosolic classes, namely, delta, epsilon, omega, sigma, theta, and zeta, and one was assigned to an "unclassified" group. The GST genes were differentially expressed in various larval tissues and at different developmental stages. Exposure to the pyrethroid insecticide lambda-cyhalothrin (LCT) caused oxidative stress in L. serricorne larvae and led to significantly elevated expression levels of six genes, among which LsGSTe1 was the most upregulated. Recombinant LsGSTE1 protein displayed LCT-metabolizing activity. Furthermore, LsGSTE1 protects cells against oxidative stress. Moreover, knockdown of LsGSTe1 by RNA interference dramatically increased the susceptibility of L. serricorne larvae to LCT treatment. The results from this study provide sequence resources and expression data for GST genes in L. serricorne. Our findings indicate that LsGSTE1 plays a dual role in LCT detoxification by metabolizing the pesticide and by preventing LCT-induced oxidative stress. Thus, the LsGSTe1 gene could be used as a potential target for sustainable management of the cigarette beetle.

Lambda-cyhalothrin enhances inflammation in nigrostriatal region in rats: Regulatory role of NF-κß and JAK-STAT signaling.

The risk to develop neurobehavioural abnormalities in humans on exposure to lambda-cyhalothrin (LCT) - a type II synthetic pyrethroid has enhanced significantly due to its extensive uses in agriculture, homes, veterinary practices and public health programs. Earlier, we found that the brain dopaminergic system is vulnerable to LCT and affects motor functions in rats. In continuation to this, the present study is focused to unravel the role of neuroinflammation in LCT-induced neurotoxicity in substantia nigra and corpus striatum in rats. Increase in the mRNA expression of proinflammatory cytokines (TNF- α, IL-1ß, IL-6) and iNOS whereas decrease in anti-inflammatory cytokine (IL-10) was distinct both in substantia nigra and corpus striatum of rats treated with LCT (0.5, 1.0, 3.0 mg/kg body weight, p.o, for 45 days) as compared to control rats. Further, LCT-treated rats exhibited increased levels of glial fibrillary acidic protein (GFAP) and ionized calcium-binding adapter molecule 1 (Iba-1), the glial marker proteins both in substantia nigra and corpus striatum as compared to controls. Exposure of rats to LCT also caused alterations in the levels of heat shock protein 60 (HSP60) and mRNA expression of toll-like receptors (TLR2 and TLR4) in the substantia nigra and corpus striatum. An increase in the phosphorylation of key proteins involved in NF-kß (P65, Iκß, IKKα, IKKß) and JAK/STAT (STAT1, STAT3) signaling and alteration in the protein levels of JAK1 and JAK2 was prominent in LCT-treated rats. Histological studies revealed damage of dopaminergic neurons and reactive gliosis as evidenced by the presence of darkly stained pyknotic neurons and decrease in Nissl substance and an increase in infiltration of immune cells both in substantia nigra and corpus striatum of LCT-treated rats. Presence of reactive microglia and astrocytes in LCT-treated rats was also distinct in ultrastructural studies. The results exhibit that LCT may damage dopaminergic neurons in the substantia nigra and corpus striatum by inducing inflammation as a result of stimulation of neuroglial cells involving activation of NF-κß and JAK/STAT signaling.

Transcription Factor AhR Regulates Glutathione S-Transferases Conferring Resistance to lambda-Cyhalothrin in Cydia pomonella.

Aryl hydrocarbon receptor (AhR) enhances insect resistance to insecticides by regulating the detoxification network. Our previous studies have confirmed that overexpressions of cytochrome P450 monooxygenases (P450s) and glutathione S-transferases (GSTs) are involved in lambda-cyhalothrin resistance in Cydia pomonella. Here, we report that CpAhR regulates the expression of GST and P450 genes, thus conferring resistance. Expression patterns indicated that the expression of CpAhR was highly induced by lambda-cyhalothrin exposure and upregulated in a lambda-cyhalothrin-resistant population. RNA interference (RNAi) of CpAhR decreases the expression of key resistance-related genes (CpGSTe3, CpCYP9A121, and CpCYP9A122) and the activity of the GST enzyme, reducing the tolerance to lambda-cyhalothrin. Furthermore, ß-naphthoflavone, a novel agonist of AhR, was first proven to be effective in increasing CpAhR expression and larval tolerance to lambda-cyhalothrin. These results demonstrate that CpAhR regulates the expression of key detoxifying genes and GST activity, resulting in the development of resistance to lambda-cyhalothrin in C. pomonella.

Biodegradation of the Pesticides Bifenthrin and Fipronil by Bacillus Isolated from Orange Leaves.

The pyrethroid bifenthrin and the phenylpyrazole fipronil are widely employed insecticides, and their extensive use became an environmental issue. Therefore, this study evaluated their biodegradation employing bacterial strains of Bacillus species isolated from leaves of orange trees, aiming at new biocatalysts with high efficiency for use singly and in consortium. Experiments were performed in liquid culture medium at controlled temperature and stirring (32 °C, 130 rpm). After 5 days, residual quantification by HPLC-UV/Vis showed that Bacillus amyloliquefaciens RFD1C presented 93% biodegradation of fipronil (10.0 mg.L-1 initial concentration) and UPLC-HRMS analyses identified the metabolite fipronil sulfone. Moreover, Bacillus pseudomycoides 3RF2C showed a biodegradation of 88% bifenthrin (30.0 mg.L-1 initial concentration). A consortium composed of the 8 isolated strains biodegraded 81% fipronil and 51% bifenthrin, showing that this approach did not promote better results than the most efficient strains employed singly, although high rates of biodegradation were observed. In conclusion, bacteria of the Bacillus genus isolated from leaves of citrus biodegraded these pesticides widely applied to crops, showing the importance of the plant microbiome for degradation of toxic xenobiotics.

Effects of prenatal and infant daily exposure to pyrethroid pesticides on the language development of 2-year-old toddlers: A prospective cohort study in rural Yunnan, China.

BACKGROUND: Prenatal and infant daily exposures to pyrethroid pesticides (PYRs), used in the elimination of harmful organisms in the family environment and agricultural activities, may have an impact on children's language development. OBJECTIVES: To determine the impacts of prenatal and infant PYRs exposure on 2-year-old toddlers' language development. METHODS: From January 2016 to December 2018, women in the third trimester of pregnancy, in Yunnan rural area, China, were recruited, and the development of their newborns was observed from birth till the age of two. We examined three PYRs metabolites: 3-phenoxybenzoic acid (3PBA), 4-fluoro-3-phenoxybenzoic acid (4F3PBA), and cis-2,2dibromovinyl-2,2-dimethylcyclopropane-1-carboxylic acid (DBCA) in urine samples collected from women in the third trimester of pregnancy and their infants of 6-8 months after birth, and assessed language development of 2-year-old toddlers by the Bayley Scales of Infant and Toddler Development-Third Edition (BSID-III). Generalized linear models were used to analyze the impacts of exposure to PYRs on 2-year-old toddlers' language development. RESULTS: The median concentrations of 3PBA, 4F3PBA and DBCA creatinine-adjusted were 0.21, 0.19, and 0.15 µg/g in pregnancy, and 0.25, 0.72, and

New insights into cypermethrin insecticide resistance mechanisms of Culex pipiens pallens by proteome analysis.

BACKGROUND: Due to the development of insecticide resistance in mosquitoes, with worldwide mosquito-borne diseases resurgence in recent years, recent advances in proteome technology have facilitated a proteome-wide analysis of insecticide resistance-associated proteins in mosquitoes. Understanding the complexity of the molecular basis of insecticide resistance mechanisms employed by mosquitoes will help in designing the most effective and sustainable mosquito control methods. RESULTS: After 30 generations, insecticide-selected strains showed elevated resistance levels to the cypermethrin used for selection. Proteome data allowed the detection of 2892 proteins, of which 2885 differentially expressed proteins (DEPs) achieved quantitative significances in four stages (egg, larvae, pupae, adult) of Culex pipiens pallens cypermethrin-resistant strain as compared to the susceptible strain. Among them, a significant enrichment of proteins, including cuticular proteins, enzymes involved in the detoxification (cytochrome P450, glutathione S-transferases, esterase, ATP-binding cassette) and some biological pathways (oxidative phosphorylation, hippo signalling) that are potentially involved in cypermethrin resistance, was observed. Thirty-one representative DEPs (cytochrome P450, glutathione S-transferase, cuticle protein) during Cx. pipiens pallens developmental stages were confirmed by a parallel reaction monitoring strategy. CONCLUSIONS: The present study confirmed the power of isobaric tags for relative and absolute quantification for identifying concomitantly quantitative proteome changes associated with cypermethrin in Cx. pipiens pallens. Proteome analysis suggests that proteome modifications can be selected rapidly by cypermethrin, and multiple resistance mechanisms operate simultaneously in cypermethrin-resistance of Cx. pipiens pallens, Our results interpret that an up-regulated expression of proteins and enzymes like cytochrome P450, glutathione S-transferases, esterase etc. has an impact in insecticide resistance. Previously neglected penetration resistance (cuticular proteins) may play an important role in the adaptive response of Cx. pipiens pallens to insecticides. This information may serve as a basis for future work concerning the possible role of these proteins in cypermethrin resistance in mosquito Cx. pipiens pallens. © 2022 Society of Chemical Industry.

Sequential phase I metabolism of pyrethroids by duplicated CYP6P9 variants results in the loss of the terminal benzene moiety and determines resistance in the malaria mosquito Anopheles funestus.

Pyrethroid resistance in Anopheles funestus is threatening the eradication of malaria. One of the major drivers of pyrethroid resistance in An. funestus are cytochrome P450 monooxygenases CYP6P9a and CYP6P9b, which are found upregulated in resistant An. funestus populations from Sub-Saharan Africa and are known to metabolise pyrethroids. Here, we have functionally expressed CYP6P9a and CYP6P9b variants and investigated their interactions with azole-fungicides and pyrethroids. Some azole fungicides such as prochloraz inhibited CYP6P9a and CYP6P9b at nanomolar concentrations, whereas pyrethroids were weak inhibitors (>100 µM). Amino acid sequence comparisons suggested that a valine to isoleucine substitution at position 310 in the active site cavity of CYP6P9a and CYP6P9b, respectively, might affect substrate binding and metabolism. We therefore swapped the residues by site directed mutagenesis to produce CYP6P9aI310V and CYP6P9bV310I. CYP6P9bV310I produced stronger metabolic activity towards coumarin substrates and pyrethroids, particularly permethrin. The V310I mutation was previously also detected in a pyrethroid resistant field population of An. funestus in Benin. Additionally, we found the first metabolite of permethrin and deltamethrin after hydroxylation, 4'OH permethrin and 4'OH deltamethrin, were also suitable substrates for CYP6P9-variants, and were depleted by both enzymes to a higher extent than as their respective parent compounds (approximately 20% more active). Further, we found that both metabolites were toxic against An. funestus FANG (pyrethroid susceptible) but not towards FUMOZ-R (pyrethroid resistant) mosquitoes, the latter suggesting detoxification by overexpressed CYP6P9a and CYP6P9b. We confirmed by mass-spectrometric analysis that CYP6P9a and CYP6P9b are capable of cleaving phenoxybenzyl-ethers in type I pyrethroid permethrin and type II pyrethroid deltamethrin and that both enzymes preferentially metabolise trans-permethrin. This provides new insight into the metabolism of pyrethroids and a greater understanding of the molecular mechanisms of pyrethroid resistance in An. funestus.

Investigation of cypermethrin toxicity in Swiss albino mice with physiological, genetic and biochemical approaches.

In this study, cypermethrin toxicity was investigated using physiological, biochemical and cytogenetic parameters, and more than one organ and cell type was preferred to determine these effects. In this multifaceted study, the genotoxicity mechanism of cypermethrin was elucidated by molecular docking. In addition, comet assay technique was applied to detect and quantify DNA damage at the cell level. For this aim, body and organ weights, aspartate aminotransferase (AST), alanine aminotransferase (ALT), malondialdehyde (MDA), glutathione (GSH), blood urea nitrogen (BUN) and creatinine levels, mitotic index (MI), DNA fragmentation, frequency of micronucleus (MN) and chromosomal aberrations (CAs) were used as indicators of toxicity. Mice were divided into 4 groups. The control group was fed with tap water and the administration groups were orally exposed to 62.5, 125 and 250 mg/kg b.w cypermethrin for 28 days. Then, the mice were sacrificed and tissue samples were collected. Cypermethrin caused a decrease in body and organ weights, GSH levels and MI and an increase in AST, ALT, MDA, BUN, creatinine levels and the frequency of MN and CAs (break, ring, gap, acentric, etc.). Cypermethrin promoted MN formation in leukocyte, erythrocyte, buccal mucosa epithelial cells. CAs and MN formation promoted by cypermethrin have been associated with DNA-cypermethrin interactions. This interaction has been demonstrated by simulation with molecular docking method and experimentally by spectral measurements of DNA. As a result, all three doses of cypermethrin caused toxicity in different cell types. In other words, the effect of cypermethrin taken into the body was not limited to only one cell type or region. Therefore, cypermethrin is a pyrethroid insecticide that promotes multifaceted toxicity in non-target organisms.

Effect of subacute poisoning with lambdacyhalothrin on vascular endothelial growth factor 2 receptor in mice kidneys.

BACKGROUND: Pyrethroids are used for insect control. They act on voltage-gated sodium channels in neurons. Lambdacyhalothrin (LCH) is a type II pyrethroid producing choreoatetosis and salivation in rodents. Vascular endothelial growth factor (VEGF) expression in the kidney is high in the glomerular podocytes and kidney tubules. VEGF receptor 2 (VEFGR2) is the main mediator in angiogenesis and it regulates blood vessel permeability. Lack of VEGF in podocytes impairs filtration. The nuclear factor κB (NFκB) is widely known as an important mediator of inflammation. The aim of the study was to check if subacute oral intoxication with 0.1LD50 of LCH affects kidney size, function and VEGFR2 and NFκB in mice kidneys. METHODS: A total of 32 Albino Swiss mice was used: females controls, males controls, females receiving 2 mg/kg LCH, males receiving 2 mg/kg LCH orally for 7 days. On day 8 animals were sacrificed, blood and kidneys were obtained. Kidney mass was determined, creatinine concentration was measured in blood sera, VEGFR2 and NFκB in kidney homogenate supernatant with ELISA kit. RESULTS: There was no statistically significant differences in kidney mass, creatinine concentration in blood sera nor NFκB but mean VEGFR2 concentration in the kidneys of females exposed to LCH was 128.01 ng/ml and showed statistically significant difference in comparison with control females. There was no statistically significant difference between VEGFR2 concentration in the kidneys of males exposed to LCH and control males. CONCLUSION: The VEGFR2 increases in the course of LCH intoxication in females probably due to the protective effect of oestrogens.

[Prenatal pyrethroid pesticides exposure and neurodevelopment of 2-year-old children: a birth cohort study].

Objective: To investigate the influence and critical windows of prenatal exposure to pyrethroid pesticides (PYRs) on neurodevelopment of 2-year-old children. Methods: The subjects of this study were derived from the Xuanwei Birth Cohort. A total of 482 pregnant women who participated in the rural district of Xuanwei birth cohort from January 2016 to December 2018 were included. Maternal urinary concentrations of PYRs metabolites during 8-12 gestational weeks, 20-23 gestational weeks and 32-35 gestational weeks were measured with ultra high performance liquid chromatography system coupled with a tandem mass spectrometry detector. Child neurodevelopment was evaluated with the Bayley Scales of Infant and Toddler Development-Third Edition at 2 years of age. Multivariate linear regression models and binary logistic regression models were used to assess the association between PYRs exposure during pregnancy and children's neurodevelopment. Results: A total of 360 mother-child pairs had complete data on maternal urinary PYRs metabolites detection and children's neurodevelopment assessment. The detection rate of any one PYRs metabolites during the first, second and third trimester were 93.6% (337/360), 90.8% (327/360) and 94.2% (339/360), respectively. The neurodevelopmental scores of Cognitive, Language, Motor, Social-Emotional, and Adaptive Behavior of 2-year-old children were (102.3±18.9), (100.2±16.3), (102.0±20.3), (107.8±23.3) and (85.8±18.6) points, respectively. After controlling for confounding factors, 4-fluoro-3-phenoxybenzoic acid (4F3PBA, one of PYRs metabolites) exposure in the first trimester reduced Motor (ß=-5.02, 95%CI: -9.08, -0.97) and Adaptive Behavior (ß=-4.12, 95%CI:-7.92, -0.32) scores of 2-year-old children, and increased risk of developmental delay of adaptive behavior (OR=2.07, 95%CI:1.13-3.82). Conclusion: PYRs exposure during the first trimester of pregnancy may affect neurodevelopment of 2-year-old children, and the first trimester may be the critical window.

Proteomics analysis reveals several metabolic alterations in cyanobacterium Anabaena sp. NC-K1 in response to alpha-cypermethrin exposure.

In the current study, the effect of the EC50 and LC90 concentrations of pyrethroid insecticide alpha-cypermethrin to cyanobacteria Anabaena sp. NC-K1 was investigated at different time exposures (1st day, 4th day and 7th day) with reference to growth, photosynthetic pigments, oxidative damage and antioxidant defence system. Superoxide dismutase (1.38-fold), peroxidase (5.04) and proline content (2.27-fold) were enhanced compared to the control. After performing 2D gel electrophoresis at 1st day EC50 exposure, where appropriate differences in the biochemical and physiological parameters were observed, 22 differentially accumulated proteins (20 upregulated and 2 downregulated) were selected for mass spectrometry. Out of 42 proteins identified, 20 upregulated protein spots were classified into twelve categories according to their metabolic functions. Proteins related to photosynthesis (phycobilisome rod-core linker polypeptide, rubisco), stress responses (Hsp70, Hsp40, catalase family peroxidase), translation (elongation factor Tu) and amino acid biosynthesis and metabolism (3-phosphoshikimate 1-carboxyvinyl transferase) were significantly upregulated. Additionally, proteins involved in transcription and DNA repair (Snf-2 histone linker phd ring helicase, RNA polymerase sigma factor RpoD and Holliday junction ATP-dependent DNA helicase RuvA) were considerably upregulated. Upregulation of these proteins against pesticide stress presumably maintained the photosynthesis, energy metabolism, carbohydrate metabolism, transport and signalling proteins, transcription, translation and DNA repair. Additionally, these proteins might involve in sufficient detoxification of ROS and play a crucial role in damage removal and repair of oxidized proteins, lipids and nucleic acids. Taken together, Anabaena sp. NC-K1 responded towards alpha-cypermethrin stress via modulating its proteome to maintain its cellular metabolism and homeostasis.

Effects of Some Insecticides (Deltamethrin and Malathion) and Lemongrass Oil on Fruit Fly (Drosophila melanogaster).

<b>Background and Objective:</b> The continuous use of pesticides in the ecosystem is of great concern, as some of them are highly stable and impact non-target organisms. The effect was tested of different concentrations of insecticides such as (Deltamethrin and Malathion) and natural products, Including, lemongrass oil on Fruit Fly (<i>Drosophila melanogaster</i>), to calculate the concentration at which the highest mortality occurred and death half the number of individuals after 96 hrs, as well as calculating the half-lethal time for individuals. <b>Materials and Methods:</b> This study, which evaluated the toxicity of five different concentrations (0.75, 1.00, 1.25, 1.50 and 1.75 mg L¹) of Malathion, (0.05, 0.10, 0.21, 0.53 and 1.48 mg L¹) of Deltamethrin and lemongrass oil (0.25, 0.50, 0.75, 1.00 and 1.50 mg L¹) on the insect of <i>Drosophila melanogaster</i> after 96 hrs of treatment. <b>Results:</b> From the results of this study, the concentration (LC₅₀= 2.938 mg L¹) of Malathion leads to kills half of the individuals, compared to Deltamethrin a higher concentration (LC₅₀= 4.8673 mg L¹) that leads to killing half of the individuals. While lemongrass oil the concentration (LC₅₀= 9.7478 mg L¹) leads to kills half of individuals. Also, when used Deltamethrin it takes (LT₅₀= 660.277) hours to kill half of the individuals compared to Malathion, which takes approximately (LT₅₀ = 321.862) hours to death half of the individuals. But lemongrass oil (LT₅₀= 819.745) hours to kill half of the individuals. <b>Conclusion:</b> In conclusion, the lemon plant and its components have excellent potential for being used in the control of <i>Drosophila melanogaster</i>, which had an effective role in biological control.