OBJECTIVES: To explore whether the antioxidant axis Nrf2/HO-1 is involved in the regulation of hippocampus injury induced by cypermethrin and its underlying mechanism. METHODS: Ten-week-old C57BL/6 mice were randomly divided into control group and cypermethrin exposure groups with low, medium, and high exposure levels. After 21 days of oral gavage of corn oil (control) or cypermethrin, the levels of MDA, T-SOD, GSH-Px and CAT in the hippocampus of the mice were examined to evaluate the oxidative stress levels. HE staining was used to observe morphological changes of the hippocampal neurons. Western blotting, immunofluorescence staining and RT-qPCR were employed to detect the protein expressions and mRNA expression of Nrf2 and HO-1 and HO-1. RESULTS: Subacute oral exposure to cypermethrin significantly increased MDA level, decreased the activities of antioxidant enzymes T-SOD, GSH-Px and CAT, and induced neuronal damage in the CA1 and CA3 regions in the hippocampus of C57BL/6 mice. Cypermethrin exposure also caused Nrf2 protein translocation from the cytoplasm to the nucleus, accompanied by upregulated expression levels of the key antioxidant factor Nrf2 and its downstream target kinase HO-1. CONCLUSIONS Cypermethrin exposure dose-dependently causes oxidative damage in the hippocampus of C57BL/6 mice, which is regulated by the Nrf2/HO-1 antioxidant pathway.
Animals ; Pyrethrins/toxicity* ; NF-E2-Related Factor 2/metabolism* ; Hippocampus/cytology* ; Mice, Inbred C57BL ; Mice ; Oxidative Stress/drug effects* ; Neurons/pathology* ; Heme Oxygenase-1/metabolism* ; Signal Transduction ; Membrane Proteins

The inappropriate utilisation of the agricultural insecticide lambda-cyhalothrin (LCT) has the potential to result in residues that compromise food safety and human health. Respiratory exposure represents a major route of LCT contact in humans. Nevertheless, its deleterious effects on the respiratory system remain inadequately characterized. It is imperative to elucidate the potential relationship and mechanisms by which lung cancer, a significant malignant neoplasm of the respiratory system, is associated with exposure to LCT. The objective of this study is to utilise bioinformatics methodologies to screen and analyse the key target molecules affected by LCT in the occurrence of lung cancer, and their mechanisms of action. Specifically, network toxicology methods were employed to identify core targets of LCT-induced lung cancer. Subsequently, functional annotation to delineate associated cellular pathways, and finally, molecular docking to simulate binding modes between LCT and shared core targets. Core target screening identified 50 targets for large cell lung cancer, 54 for small cell lung cancer, 29 for lung squamous cell carcinoma, and 28 for lung adenocarcinoma, with EGFR, HSP90AA1, JUN, CCL2, MYC, CXCL8, and HSPA4 shared in all subtypes. Functional annotation revealed that LCT-triggered oncogenic pathways predominantly involved ubiquitination, chemotaxis, and tumor immune signaling. Molecular docking demonstrated spontaneous binding of LCT to core targets mediated by hydrogen bonds and π-cation interactions. These results establish a theoretical framework for evaluating LCT-associated risks of lung cancer and respiratory system damage.
Lung Neoplasms/metabolism* ; Pyrethrins/toxicity* ; Humans ; Insecticides/toxicity* ; Nitriles/toxicity* ; Molecular Docking Simulation

Esfenvalerate is a kind of commonly used highly effective pyrethroid insecticide. It is common for people who are poisoned by contact or misuse, but rarely reported for people who are poisoned by intramuscular injection. This paper reports a case of intramuscular injection of esfenvalerate in the Department of Infection, West China Hospital of Sichuan University in November 2021. The patient was intramuscularly injected with about 20 ml of esfenvalerate, inducing the sense of swelling and tingling, degeneration and necrosis of striated muscle tissue at the injection site, also liver function damage and other manifestations. The patient was discharged from hospital after rehydration, accelerating poison metabolism, anti-infection, liver protection and local puncture.
Humans ; Insecticides ; Injections, Intramuscular ; Pyrethrins ; Nitriles/metabolism*

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 (β=-5.02, 95%CI: -9.08, -0.97) and Adaptive Behavior (β=-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.
Birth Cohort ; Child Development ; Child, Preschool ; Cohort Studies ; Female ; Humans ; Infant ; Maternal Exposure/adverse effects* ; Pesticides/adverse effects* ; Pregnancy ; Pregnancy Trimester, Third ; Prenatal Exposure Delayed Effects/chemically induced* ; Pyrethrins/metabolism*

OBJECTIVETo investigate the mechanism of di-2-ethylhexyl phthalate (DEHP) and cypermethrin (CYP) inducing gonadal dysgenesis in prepubertal male rats.

METHODSA total of 40 healthy 3-week-old specific pathogen-free male Sprague-Dawley rats were randomly and equally divided into four groups: control group (corn oil), DEHP group (500 mg/kg, dissolved in corn oil), CYP group (80 mg/kg, dissolved in corn oil), and combined exposure group (exposed to 500 mg/kg DEHP and 80 mg/kg CYP, dissolved in corn oil). Rats were treated by gavage administration once a day for 30 days. Twenty-four hours after the last exposure, the animals were sacrificed. The body weight and the wet weight of testis were determined, and the weight coefficient of testis was calculated. Radioimmunoassay was used to determine serum testosterone level. Ultrastructural-level histopathological changes of the testis were examined by transmission electron microscopy. The mRNA and protein expression of follicle stimulating hormone receptor (FSHR), androgen binding protein (ABP), inhibin beta-B (INHBB) and vimentin (VIM) were analyzed by real-time PCR and Western blot, respectively. Factorial design analysis of variance was used to compare differences between groups; interaction diagrams were used to determine the interaction between DEHP and CYP.

RESULTSCompared with those of the control group, the testis weights and testis coefficients of the DEHP, CYP, and combined exposure groups significantly decreased by 39.3-59.2%and 19.7-58.6%, respectively, and all exposure groups showed significant reductions in serum level of testosterone, ranging from 49.1% to 62.7% (P < 0.05 or P < 0.01). And all the exposure groups showed different levels of ultrastructural damages in the testes. Compared with that in the control group, the mRNA expression of FSHR, ABP, INHBB, and VIMin the DEHP group was down-regulated by 1.72, 2.64, 2.83 and 1.79 times, and their protein levels were significantly reduced by 65.2%, 53.7%, 70.1%, and 51.9% (P < 0.05 or P < 0.01). Significant decreases in mRNA expression of ABP (down 1.72 times) and INHBB (down 2.06 times) were observed in the CYP group, and their protein levels decreased by 38.3% and 49.7%, respectively (P < 0.05). The combined exposure to both DEHP and CYP resulted in big decreases in the mRNA levels of FSHR (down 1.62 times), ABP (down 2.00 times), INHBB (down 2.35 times), and VIM (down 1.54 times) and protein levels of FSHR (down 52.1%), INHBB (down 53.9%), and VIM (down 58.8%) (P < 0.05). Factorial design analysis of variance showed that the combination of two substances had an antagonistic effect on the expression of ABP and INHBB (P < 0.05).

CONCLUSIONDEHP and CYP, alone or combined, can lead to gonadal dysgenesis in prepubertal male rats. Both of them can disrupt functional mRNA and protein expression in Sertoli cells to certain levels. The combination of DEHP and CYP shows antagonistic effects, and DEHP has a stronger reproductive toxicity than CYP.

Animals ; Diethylhexyl Phthalate ; toxicity ; Gonadal Dysgenesis ; chemically induced ; Male ; Pyrethrins ; toxicity ; Rats ; Rats, Sprague-Dawley ; Sertoli Cells ; metabolism ; Testis ; cytology ; drug effects

OBJECTIVE: To establish an animal model in acute poisoned rat by deltamethrin and an analysis method for determination of deltamethrin by gas chromatography-electron capture detector (GC-ECD) and to study the distribution of deltamethrin in rats in order to provide the references for forensic medicine identification about such cases. METHODS: Rats were administered with deltamethrin of different doses(512 and 1,024 mg/kg) and killed 1.5 h later to be dissected rapidly for tissues (blood, hearts, livers, lungs, kidneys and brains etc.). Samples were dehydrated by anhydrous sodium sulfate and extracted with petroleum ether and acetone (V:V=4:1). The level of deltamethrin was determined by GC-ECD. RESULTS: There was a good separate between deltamethrin and endogenous impurities. The limit of quantification for deltamethrin in blood and liver were 0.1 microg/mL and 0.1 microg/g (S/N> or =10), respectively. The recovery rate of deltamethrin in blood was 91.55%-134.37% and both inter-day and intra-day precisions were less than 5.67%. The distribution of deltamethrin in poisoned rats with 512 mg/kg was as follow: lungs > livers > hearts > kidneys > blood > brains and with 1 024 mg/kg dose was lungs > blood > hearts > kidneys > brains > livers (P<0.05). CONCLUSION The GC-ECD method is sensitive for determination of deltamethrin. The distribution of deltamethrin in rats has a dose-dependent manner. The study suggests that samples of blood, hearts, livers, lungs, kidneys and brains are suitable for deltamethrin poisoned analysis.
Animals ; Chromatography, Gas/methods* ; Disease Models, Animal ; Forensic Toxicology/methods* ; Kidney/metabolism* ; Linear Models ; Liver/metabolism* ; Lung/metabolism* ; Male ; Nitriles/poisoning* ; Pyrethrins/poisoning* ; Rats ; Reproducibility of Results ; Sensitivity and Specificity ; Tissue Distribution

OBJECTIVETo evaluate histopathological alterations of the liver and kidney of female rats exposed to low doses of DM and its potential genotoxic activity.

METHODSFemale Wistar rats were randomly assigned to control (3 groups, 6 rats in each) and treatment groups (3 groups, 6 rats in each). They were subjected to subcutaneous injections of DM (at doses of 0.003, 0.03, and 0.3 mg/kg bw/d) after 30, 45, and 60 d, respectively.

RESULTSSignificant alterations were recorded in liver parenchyma induced by hepatic vacuolization, fragmented chromatin in nuclei, dilatation of sinusoids and congestions. Lesions within proximal and distal tubules were observed in the kidneys. Tissue congestions and severe alterations within glomeruli were visible. DM as a pyrethroid insecticide induced significant increase (P≤0.05) of plasma MDA concentrations after 45 d. A significant increase (P≤0.05) in plasma ALT (after 45 and 60 d) and AST (after 60 d) concentrations was recorded as compared to controls. During the whole experimental period the toxic agent provoked significant DNA damages (P≤0.05), especially in the dominance of classes 3 and 4 of obtained comet.

CONCLUSIONDM even at a very low dose displays harmful effects by disrupting hepatic and renal function and causing DNA damages in puberscent female rats. Low doses of DM are hepatotoxic and nephrotoxic.

Animals ; Aspartate Aminotransferases ; metabolism ; Behavior, Animal ; drug effects ; Chemical and Drug Induced Liver Injury ; metabolism ; pathology ; Creatinine ; blood ; Dose-Response Relationship, Drug ; Female ; Insecticides ; administration & dosage ; chemistry ; toxicity ; Kidney ; drug effects ; Kidney Diseases ; chemically induced ; pathology ; Liver ; drug effects ; Malondialdehyde ; Molecular Structure ; Nitriles ; administration & dosage ; chemistry ; toxicity ; Organ Size ; Oxidative Stress ; drug effects ; Pyrethrins ; administration & dosage ; chemistry ; toxicity ; Random Allocation ; Rats ; Urea ; blood ; Weight Gain ; drug effects

OBJECTIVETo evaluate the influence on the synaptic protein expression in different brain regions of ICR mice after lambda-cyhalothrin (LCT) exposure during postnatal period.

METHODSTwo male and 4 female healthy ICR mice were put in one cage. It was set as pregnancy if vaginal plug was founded. Offspring were divided into 5 groups randomly, and exposed to LCT (0.01% DMSO solution) at the doses of 0.1, 1.0 and 10.0 mg/kg by intragastric rout every other day from postnatal days (PND) 5 to PND13, control animals were treated with normal saline or DMSO by the same route. The brains were removed from pups on PND 14, the synaptic protein expression levels in cortex, hippocampus and striatum were measured by western blot.

RESULTSGFAP levels of cortex and hippocampus in the LCT exposure group increased with doses, as compared with control group (P < 0.05), while Tuj protein expression did not change significantly in the various brain regions of ICR mice. GAP-43 protein expression levels in the LCT exposed mouse hippocampus and in female ICR mouse cortex increased with doses, as compared with control group (P < 0.05). Presynaptic protein (Synapsin I) expression levels did not change obviously in various brain regions. However, postsynaptic density protein 95 (PSD95) expression levels of the hippocampus and striatum in male offspring of 10.0 mg/kg LCT group, of cortex of female LCT groups, and of female offspring in all exposure groups, of striatum, in 1.0 or 10.0 mg/kg LCT exposure groups significantly decreased (P < 0.05).

CONCLUSIONSEarly postnatal exposure to LCT affects synaptic protein expression. These effects may ultimately affect the construction of synaptic connections.

Animals ; Animals, Newborn ; Brain ; drug effects ; metabolism ; Corpus Striatum ; drug effects ; metabolism ; Female ; Hippocampus ; drug effects ; metabolism ; Male ; Mice ; Mice, Inbred ICR ; Nitriles ; toxicity ; Pyrethrins ; toxicity ; Synapsins ; metabolism

Present study was undertaken to study the effect of cypermethrin on oxidative stress after chronic dermal application. The insecticide was applied dermally at 50 mg/kg body weight in different groups of Wistar rats of either sex weighing 150~200 g. Significant (p < 0.05) increase in catalase activity was observed after 30 days of exposure. However, the superoxide dismutase activity declined significantly after 60 days of exposure. The activity of glutathione peroxidase and blood glutathione levels declined significantly (p < 0.05) after 30 days of cypermethrin dermal application. However, the activity of glutathione S-transferase increased significantly (p < 0.05) in all groups after 60 days of dermal exposure. Significant increase in lipid peroxidation was observed from 30 days onwards and reached a peak after 120 days of application.
Administration, Cutaneous ; Animals ; Female ; Glutathione/blood ; Insecticides/*toxicity ; Lipid Peroxidation/*drug effects ; Male ; Oxidative Stress/*drug effects ; Oxidoreductases/metabolism ; Pyrethrins/*toxicity ; Rats ; Rats, Wistar

Animals ; Cells, Cultured ; Interleukin-1beta ; pharmacology ; Male ; Neurons ; drug effects ; metabolism ; Nitric Oxide ; metabolism ; Nitriles ; toxicity ; Pyrethrins ; toxicity ; Rats ; Rats, Sprague-Dawley ; Sodium-Potassium-Exchanging ATPase ; metabolism