Reproductive toxicity and histopathological changes induced by lambda-cyhalothrin in male mice

Efficient removal of Lambda-cyhalothrin from simulated water using Co-composted-biochar: A modern day substituent of conventional bioadsorbent

Lambda-cyhalothrin, a type II pyrethroid, is widely employed as an outdoor and indoor insect repellent due to its target specificity and moderate toxicity. However, its extensive use elevated its residual concentration to significant detectable levels in waterbodies, making it an immediate problem. Furthermore, as a lipophile, its accumulation in multicellular organisms has resulted in irreversible acute and chronic effects on numerous physiochemical and biological activities. Thus, to address its removal as a pollutant from waterbodies, bio-adsorbents are considered a cost-effective and environmentally sound cleanup method. Modern day bio-adsorbents like co-composted-biochar, because of their potential adsorption capability rather than the conventional ones, may become a commonly used remediation tool. Therefore, this study aims at producing co-composted-biochar (COMBI) by combining kitchen-derived putrescible waste and biochar to effectively remove Lambda-cyhalothrin (LC) from spiked up water. It has been further analysed for its physico-chemical characteristics using instrumentation such as BET, SEM-EDS and FTIR. The results showed that biochar and COMBI had a much greater surface area (2.174 m2/g-1.718 m2/g) and pore diameters (3.648 nm-3.628 nm) than the compost sample. Simultaneously, the response surface methodology (RSM) was employed to optimise the removal efficiency of COMBI against LC. A Box-Behnken Design (BBD) was developed with an experimental layout to perform tests for determining the effects of four basic parameters i.e. pH, contact time (minute), adsorbate concentration (g/l) and adsorbent dose (g) on (%) removal of LC. It was noted that variation among removal efficiencies for the experimental runs ranges between 94.8% and 99.9%, within the majority attaining an efficiency of greater than 95%. During the experiments, the ideal conditions were found to be as pH 2 in a contact time of 140 min and a dose of adsorbent 0.01 g. Thus, COMBI could be a promising and potential candidate for the elimination of LC.

Ampligo® 150 ZC affect the expression of sex hormone receptors and cell proliferation marker in female rabbit ovary: Protective effects of thyme essential oil and vitamin C

Pesticides tend to cause serious reproductive defects, disturbing endocrine functions and reducing fertility, especially in females. The objective of this work was to identify the reprotoxic effects of Ampligo® 150 ZC (AP), a mixture formulation of lambda cyhalothrin and chlorantraniliprole, on the ovary of female rabbits (Oryctolagus cuniculus) and the possible protective effect of co-treatment with thyme essential oil (TEO), extracted from (Thymus vulgaris) species, and vitamin C (vit C). Twenty female rabbits were divided into four equal groups (n = 5): Control (distilled water), AP (20 mg/ kg bw of the insecticide mixture every other day, by gavage for 28 days), AP+TEO (20 mg/ kg bw of AP + 0.5 mg/ kg bw of TEO every other day), and AP+TEO+Vit C (20 mg/ kg bw of AP + 0.5 mg/ kg bw of TEO + 200 mg/ kg bw of vitamin C every other day). The effects were tested on body weight, ovary histomorphometry, and immunohistochemical expression of AFP, estrogen receptor (ER), and progesterone receptor (PR). The results revealed that AP decreased body and ovarian weights, caused ovarian histological damages, and increased collagen fiber deposition. The immunostaining of the ovary showed a significant (p < .001) increase in AFP and decrease in both ER and PR expressions. In the opposite, co-administration of TEO and vitamin C was effective in improving all caused alterations. In conclusion, combined use of TEO and vitamin C ameliorated the toxic effects of Ampligo® on the ovary in female rabbits.

The potential endocrine-disrupting of fluorinated pesticides and molecular mechanism of EDPs in cell models

Environmental endocrine disruptors constitute a category of exogenous compounds that interfere with the endocrine system's functions in organisms or cells. As a class of particularly representative endocrine-disrupting chemicals, the accumulation of per- and polyfluoroalkyl substances potentially leads to adverse health effects, including hormonal disruptions, developmental issues, and cancer. However, the classification of these disruptors is intricate, and the data on their potential health risks is scattered. The research into fluorinated pesticides is somewhat superficial, with the majority of review articles in this field focusing on the structural characteristics, biodegradation processes, and environmental risks associated with these pesticides. In this study, we compared and investigated the research development processes of seven types of fluorine-containing pesticides and five types of fluorinated endocrine disruptors. The varying toxic effects of these endocrine disruptors are highly dependent on exposure conditions. Their actions are complex, affecting behavioral substances throughout the organism, and monitoring some complex biological phenotypes, sex- or age-specific effects, and behavioral learning poses significant challenges. The findings will serve as a reference for future studies on the toxicity of pesticides to humans and other organisms.

Evaluation of acute toxicity of Scabiosa artropurperea var.maritima aqueous extracts in Swiss mice

Scabiosa artropurperea var.maritima is a plant widely distributed in the Mediterranean region and used as a traditional medicine. The present study evaluated the biochemical composition and the potential toxicity of aqueous extract of whole Scabiosa artropurperea var.maritima through acute toxicity oral administration in male mice. Phytochemical analysis of the Scabiosa artropurperea var.maritima revealed high levels of reductor sugars and significant flavonoid and total phenol content. The aqueous extract of Scabiosa artropurperea var.maritima was daily oral administered to mice at doses of 300 (group 1), 2000 (group 2) and 4000 (group 3) mg/kg body weight per day for 14 days. We observed no significant difference in the consumption of food, body weight and relative organ weights except for an increase in the seminal vesicles weight in group 3. Hematological parameters revealed the non-adverse effects of prolonged oral consumption of Scabiosa artropurperea var.maritima except for a slight increase but significant of percentage of hematocrit in group 1 and 3 and a decrease in percentage of granulocytes in group 2. The histopathologic examination did not show any differences in vital organs. We also observed non-adverse effects on the reproductive parameters including testosterone concentration, spermatozoa motility and morphologies. Based on our findings, the aqueous extract of Scabiosa artropurperea var.maritima could be considered safe for oral medication in animals.

Ascorbic acid modulates testicular toxicity of Ampligo® 150 ZC insecticide in male rabbit (Oryctolagus cuniculus)

The present study was designed to evaluate the protective effects of ascorbic acid (AA) against lambda cyhalothrin insecticide formulation Ampligo® (AP)-induced testicular toxicity in rabbit laboratory strain ITELV2006 (Oryctolagus cuniculus). Twenty rabbits were randomly divided into four equal groups and treated by oral gavage for 21 consecutive days: Group 1 served as a control and received 1 ml of distilled water, group 2 was supplemented with1ml of ascorbic acid (AA) dilution (200 mg/kg b.w), Group 3 was treated with a dose of AP at 20 mg/kg bw (1 µl/1 ml of distilled water/animal), whereas group 4 was co-administered AA and AP as the same dose of group 2 and 3, respectively. Hormonal, histomorphometrical, and immunohistochemical methods were performed at the end of the study to detect testes damage. The results showed that AP exposure significantly reduced body weight, absolute and relative testicular weights, and testosterone levels. AP caused changes in testes tissue, namely incomplete spermatogenic series and necrosis of the spermatogonial cells lining in the seminiferous tubules of rabbits. Co-administrating AA clearly modulated body and testes weights, hormonal parameters, and histopathological damage. Furthermore, the findings revealed a significant increase in alpha-fetoprotein (AFP) level expression in the testes of the AP group. However, supplementation of the AP rabbits with AA modulated the observed result. Taken together, these data suggest that AA may protect against Ampligo-induced testicular damage.

Ameliorative effect of L-carnitine on lambda-cyhalothrin-induced anatomical and reproductive aberrations in albino mice

The objective of this research was to look at how the pesticide lambda-cyhalothrin (LCT) affected the liver, kidney, testis, and ovary of albino mice; and on morphological and skeletal features of the newborn of treated females. The study also aimed to test the ameliorative effects of L-carnitine (LC) against (LCT). Five sets of mice were created, Group 1 acted as the control, while Group 2 received a high dose of LCT, Group 3 received a high dose of LCT + LC, Group 4 received a low dose of LCT that was a residue of in khat (Qat), and Group 5 received a low dose of LCT + LC. The findings revealed that the treated groups' body weights were reduced significantly, whereas the absolute and relative weights of the liver in all groups were statistically decreased insignificantly. There were histopathological changes in the tissues in groups 2 and 4. While the tissues of the ovary and testis showed recovery in groups 3 and 5. When compared to the control group, the values of the seminiferous tubules parameters were statistically significant in the 3 and 5 groups. The newborn had a high dose of pesticides and showed some malformations in the skeleton. However, in group 3 the skeletal malformation was minimized and in-group 5 the skeleton malformations had completely disappeared. It could be concluded that LCT is highly harmful to mouse tissues and caused neonatal malformations, whereas LC has a marked protective effect against LCT.

Green Synthesis of Flower-Shaped Copper Oxide and Nickel Oxide Nanoparticles via Capparis decidua Leaf Extract for Synergic Adsorption-Photocatalytic Degradation of Pesticides

Green manufacturing of catalysts enables sustainable advanced oxidation processes and water treatment processes for removing trace contaminants such as pesticides. An environmentally friendly biosynthesis process produced high-surface-area CuO and NiO nanocatalysts using phytochemicals in the Capparis decidua leaf extract, which served as a reductant and influenced catalyst shape. Capparis decidua is a bushy shrub, widely distributed in dry and arid regions of Africa, Pakistan, India, Egypt, Jordan, Sudan, Saudi Arabia. The synthesized CuO and NiO nanoparticles were characterized by UV-vis spectroscopy (UV-vis), field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDS), Fourier transform infrared spectroscopy (FT-IR), and X-ray diffraction (XRD) and thermo-gravimetric analysis/differential thermal analysis (TGA/DTA). The produced nanoparticles were spherical and flower-like in shape and have a characteristic face-centered cubic structure of CuO and NiO. Biosynthesized catalysts were photoactive and degraded recalcitrant pesticide Lambda-cyhalothrin (L-CHT). Photocatalytic degradation of L-CHT was affected by the initial L-CHT concentration, solution pH levels between 5 and 9, and photocatalyst concentration. The L-CHT removal percentage attained by CuO photocatalyst (~99%) was higher than for NiO photocatalyst (~89%). The degradation of L-CHT follows a pseudo-first-order kinetic model, and the apparent rate constant (kapp) decreased from 0.033 min−1 for CuO to 0.0084 min−1 for NiO photocatalyst. The novel flower-shaped nanoparticles demonstrated high stability in water and recyclability for removing L-CHT pesticide contamination in water.

Effect of pyrethroid pesticides on the testis of male rats: A meta-analysis

This study quantitatively evaluated the effects of pyrethroid pesticides on the testis of male rats. An extensive literature search for relevant studies was conducted on PubMed, Web of Science, Excerpta Medica Database, the Chinese National Knowledge Infrastructure, and Chinese Biomedical Literature Database. Pooled standard mean difference with corresponding 95% confidence interval was calculated via the random-effects model. I ² was used to evaluate heterogeneity among studies. A total of 19 studies were included for analysis in our study. Results indicated that the sperm count of rats exposed to fenvalerate was lower than that of rats in control groups. The sperm count, sperm motility, and testosterone level of rats exposed to cypermethrin and deltamethrin were lower than those of rats in control groups. Moreover, the sperm morphology of rats exposed to these pyrethroid pesticides was abnormal compared with that of rats in control groups. The present meta-analysis indicates that pyrethroid pesticides decrease rat sperm count, sperm motility, and testosterone level and cause abnormal rat sperm morphology. Therefore, pyrethroid pesticides can damage the testis of male rats.

Pyrethroids Toxicity to Male Reproductive System and Offspring as a Function of Oxidative Stress Induction: Rodent Studies

Pyrethroids may be related to male reproductive system damage. However, the results of many previous studies are contradictory and uncertain. Therefore, a systematic review and a meta-analysis were performed to assess the relationship between pyrethroid exposure and male reproductive system damage. A total of 72 articles were identified, among which 57 were selected for meta-analysis, and 15 were selected for qualitative analysis. Pyrethroid exposure affected sperm count (SMD= -2.0424; 95% CI, -2.4699 to -1.6149), sperm motility (SMD=-3.606; 95% CI, -4.5172 to -2.6948), sperm morphology (SMD=2.686; 95% CI, 1.9744 to 3.3976), testis weight (SMD=-1.1591; 95% CI, -1.6145 to -0.7038), epididymal weight (SMD=-1.1576; 95% CI, -1.7455 to -0.5697), and serum testosterone level (SMD=-1.9194; 95% CI, -2.4589 to -1.3798) in the studies of rats. We found that gestational and lactational exposure to pyrethroids can reduce sperm count (SMD=1.8469; 95% CI, -2.9010 to -0.7927), sperm motility (SMD=-2.7151; 95% CI, -3.9574 to -1.4728), testis weight (SMD=-1.4361; 95% CI, -1.8873 to -0.9848), and epididymal weight (SMD=-0.6639; 95% CI, -0.9544 to -0.3733) of F1 offspring. Exposure to pyrethroids can increase malondialdehyde (SMD=3.3451; 95% CI 1.9914 to 4.6988) oxide in testes and can reduce the activities of glutathione (SMD=-2.075; 95% CI -3.0651 to -1.0848), superoxide dismutase (SMD=-2.4856; 95% CI -3.9612 to -1.0100), and catalase (SMD=-2.7564; 95% CI -3.9788 to -1.5340). Pyrethroid exposure and oxidative stress could damage male sperm quality. Gestational and lactational pyrethroid exposure affects the reproductive system of F1 offspring.

Environmental relevant concentration of λ-cyhalothrin and 3-phenoxybenzoic acid caused endocrine-disrupting effects on male lizards (Eremias argus)

In the present study, the endocrine toxicity of LCT and PBA was investigated through exposure to Eremias argus for two weeks under environmental relevant concentration. RNA-sequencing identified 4442 and 4653 differentially expressed genes in lizard liver after LCT and PBA exposure. Four differentially expressed genes (hsd17β, ar, sult, ugt) related with hypothalamic-pituitary-gonadal axis were quantified by qPCR. The expression of genes associated with HPG axis in different tissues differed significantly. In LCT treatment group, ar, cyp17 and hsd3β genes involved in testosterone synthesis and transportation were significantly decreased in lizard testes, and the spermatogensis was inhibited in the testes, which indicated the anti-androgenic activity of LCT. After PBA exposure, the genes related with estradiol synthesis, transportation and metabolism, such as hsd17β, erα, ugt in lizard liver were important biomarkers and the significant decrease of estradiol level was highly correlated with hsd17β, erα, ugt gene expressions. The relative high binding affinity of PBA with ERα further demonstrated the anti-estrogenic activity of PBA. Our results elucidate the different toxic mechanism of LCT and PBA on lizard endocrine system at environmental relevant concentration. Pyrethroids metabolism may cause more seriously toxicity rather than detoxification.

A high-throughput method for unbiased quantitation and categorization of nuclear morphology†

The physical arrangement of chromatin in the nucleus is cell type and species-specific, a fact particularly evident in sperm, in which most of the cytoplasm has been lost. Analysis of the characteristic falciform (“hook shaped”) sperm in mice is important in studies of sperm development, hybrid sterility, infertility, and toxicology. However, quantification of sperm shape differences typically relies on subjective manual assessment, rendering comparisons within and between samples difficult.

We have developed an analysis program for morphometric analysis of asymmetric nuclei and characterized the sperm of mice from a range of inbred, outbred, and wild-derived mouse strains. We find that laboratory strains have elevated sperm shape variability both within and between samples in comparison to wild-derived inbred strains, and that sperm shape in F1 offspring from a cross between CBA and C57Bl6J strains is subtly affected by the direction of the cross. We further show that hierarchical clustering can discriminate distinct sperm shapes with greater efficiency and reproducibility than even experienced manual assessors, and is useful both to distinguish between samples and also to identify different morphological classes within a single sample.

Our approach allows for the analysis of nuclear shape with unprecedented precision and scale and will be widely applicable to different species and different areas of biology.

Effects and mechanisms of pyrethroids on male reproductive system

Synthetic pyrethroids are used as insecticides in agriculture and a variety of household applications worldwide. Pyrethroids are widely distributed in all environmental compartments and the general populations are exposed to pyrethroids through various routes. Pyrethroids have been identified as endocrine-disrupting chemicals (EDCs) which are responsible for the male reproductive impairments. The data confirm pyrethroids cause male reproductive damages. The insecticides exert the toxic effects on male reproductive system through various complex mechanisms including antagonizing androgen receptor (AR), inhibiting steroid synthesis, affecting the hypothalamic-pituitary-gonadal (HPG) axis, acting as estrogen receptor (ER) modulators and inducing oxidative stress. The mechanisms of male reproductive toxicity of pyrethroids involve multiple targets and pathways. The review will provide further insight into pyrethroid-induced male reproductive toxicity and mechanisms, which is crucial to preserve male reproductive health.

Ginseng aqueous extract ameliorates lambda-cyhalothrin-acetamiprid insecticide mixture for hepatorenal toxicity in rats: Role of oxidative stress-mediated proinflammatory and proapoptotic protein expressions

This study was carried out to evaluate the protective effects of Panax ginseng aqueous extract (GAE) against hepatorenal toxicity induced by lambda-cyhalothrin-acetamiprid insecticide mixture in rats. A total of 32 male albino rats were assigned into four groups. Normal control group received distilled water. Insecticide control group intoxicated with the insecticide at a dose of 2.14 mg/kg b.wt orally day after day for 45 days. GAE control group was treated with GAE at a dose 200 mg/kg b.wt orally. GAE experimental group was administered GAE 1 hour before insecticide administration. Intoxication of rats with the insecticide caused a significant increase in serum aspartate aminotransferase and alanine aminotransferase activities and urea and creatinine levels as well as malondialdehyde concentration and proteins expression of caspase-3 and induced nitric oxide synthase in hepatic and renal tissues. However, it decreased the serum levels of total protein and globulin and reduced the glutathione content and catalase activity in hepatic and renal tissues. In addition, insecticide induced histopathological alterations in both hepatic and renal tissues. In contrast, GAE modulated insecticide-induced alterations in liver and kidney functions and structures as it ameliorated the effects of insecticide on the above mentioned parameters. These results indicated that GAE was a potent antioxidant agent that could protect rats against insecticide-induced hepatorenal toxicity.

Insight Into Microbial Applications for the Biodegradation of Pyrethroid Insecticides

Pyrethroids are broad-spectrum insecticides and presence of chiral carbon differentiates among various forms of pyrethroids. Microbial approaches have emerged as a popular solution to counter pyrethroid toxicity to marine life and mammals. Bacterial and fungal strains can effectively degrade pyrethroids into non-toxic compounds. Different strains of bacteria and fungi such as Bacillus spp., Raoultella ornithinolytica, Psudomonas flourescens, Brevibacterium sp., Acinetobactor sp., Aspergillus sp., Candida sp., Trichoderma sp., and Candia spp., are used for the biodegradation of pyrethroids. Hydrolysis of ester bond by enzyme esterase/carboxyl esterase is the initial step in pyrethroid biodegradation. Esterase is found in bacteria, fungi, insect and mammalian liver microsome cells that indicates its hydrolysis ability in living cells. Biodegradation pattern and detected metabolites reveal microbial consumption of pyrethroids as carbon and nitrogen source. In this review, we aim to explore pyrethroid degrading strains, enzymes and metabolites produced by microbial strains. This review paper covers in-depth knowledge of pyrethroids and recommends possible solutions to minimize their environmental toxicity.

Permethrin and ivermectin modulate lipid metabolism in steatosis-induced HepG2 hepatocyte

Recent studies have reported the positive association between exposure to insecticides and increased risk of obesity and type 2 diabetes, which are closely associated with non-alcoholic fatty liver disease (NAFLD). However, it is not known if insecticide exposure can contribute to NAFLD. Thus, the goal of the current study was to determine if insecticide exposures can exacerbate the physiological conditions of NAFLD by modulating hepatic lipid metabolism. The effects of 12 insecticides on triglycerides (TG) accumulation were tested using palmitic acid (PA)-induced HepG2 hepatoma steatosis model. Results showed that among tested insecticides, permethrin and ivermectin significant interacted with palmitic acid to potentiate (permethrin) or decrease (ivermectin) TG accumulation. Further study showed that permethrin significantly promoted fatty acid synthesis, while suppressed lipid oxidation-related genes only under steatosis conditions. In comparison, ivermectin inhibited lipogenesis-related genes and promoted farnesoid X receptor, which upregulates fatty acid oxidation. Results in this study suggested that hepatic lipid metabolism may be more susceptible to insecticide exposure in the presence of excessive fatty acids, which can be associated with the development of NAFLD.

Effects of pyrethroid insecticides on hypothalamic-pituitary-gonadal axis: A reproductive health perspective

Pyrethroids, a class of ubiquitous insecticides, have been recognized as endocrine-disrupting chemicals (EDCs). A lot of studies have implied the endocrine-disrupting effects of pyrethroids on the hypothalamic-pituitary-gonadal (HPG) axis. However, there are few review articles regarding the effects of pyrethroids on the HPG axis of mammal and human, especially new research progress made in this area. The present review sums up the effects of pyrethroids on the HPG axis-related reproductive outcomes, including epidemiological investigations based on human biomonitoring, animal studies and in vitro tests. Mechanisms have described that the endocrine-disrupting effects of pyrethroids on mammal can be mediated via the interaction with steroid receptors, the direct action on ion channels and signaling molecules. Finally, we summarize the current research gaps and suggest future directions in this topic.

Ameliorative and protective effects of ginger and its main constituents against natural, chemical and radiation-induced toxicities: A comprehensive review

Fatal unintentional poisoning is widespread upon human exposure to toxic agents such as pesticides, heavy metals, environmental pollutants, bacterial and fungal toxins or even some medications and cosmetic products. In this regards, the application of the natural dietary agents as antidotes has engrossed a substantial attention. One of the ancient known traditional medicines and spices with an arsenal of metabolites of several reported health benefits is ginger. This extended literature review serves to demonstrate the protective effects and mechanisms of ginger and its phytochemicals against natural, chemical and radiation-induced toxicities. Collected data obtained from the in-vivo and in-vitro experimental studies in this overview detail the designation of the protective effects to ginger's antioxidant, anti-inflammatory, and anti-apoptotic properties. Ginger's armoury of phytochemicals exerted its protective function via different mechanisms and cell signalling pathways, including Nrf2/ARE, MAPK, NF-ƙB, Wnt/β-catenin, TGF-β1/Smad3, and ERK/CREB. The outcomes of this review could encourage further clinical trials of ginger applications in radiotherapy and chemotherapy regime for cancer treatments or its implementation to counteract the chemical toxicity induced by industrial pollutants, alcohol, smoking or administered drugs.

Lambda-cyhalothrin delays pubertal Leydig cell development in rats

Lambda-cyhalothrin (LCT) is a widely used broad-spectrum pyrethroid insecticide and is expected to cause deleterious effects on the male reproductive system. However, the effects of LCT on Leydig cell development during puberty are unclear. The current study addressed these effects. Twenty-eight-day-old male Sprague Dawley rats orally received LCT (0, 0.25, 0.5 or 1 mg/kg body weight/day) for 30 days. The levels of serum testosterone, luteinizing hormone, and follicle-stimulating hormone, Leydig cell number, and its specific gene and protein expression were determined. LCT exposure lowered serum testosterone levels at doses of 0.5 and 1 mg/kg and luteinizing hormone levels at a dose of 1 mg/kg, but increased follicle-stimulating hormone levels at doses of 0.5 and 1 mg/kg. LCT lowered Star and Hsd3b1 mRNA or their protein levels at a dose of 1 mg/kg. Immature Leydig cells were purified from pubertal rats and treated with different concentrations of LCT for 24 h and medium androgen levels, Leydig cell mRNA and protein levels, the mitochondrial membrane potential (△Ψm), and the apoptotic rate of immature Leydig cells were investigated. LCT inhibited androgen production at 5 μM and downregulated Scarb1 at 0.05 μM, Hsd3b1 and Hsd11b1 at 0.5 μM, and Cyp11a1 at 5 μM. LCT also decreased △Ψm at 0.5 and 50 μM. In conclusion, LCT can influence the function of Leydig cells.

The investigation of the pyrethroid insecticide lambda-cyhalothrin (LCT)-affected Ca2+ homeostasis and -activated Ca2+-associated mitochondrial apoptotic pathway in normal human astrocytes: The evaluation of protective effects of BAPTA-AM (a selective Ca2+ chelator)

Exposure to insecticides has been found to have deleterious effects on human health. Lambda-cyhalothrin (LCT), a mixture of isomers of cyhalothrin, is a pyrethroid insecticide routinely used in pest control programs. LCT was reported to cause neurotoxic effects in various models. However, the mechanism of underlying effect of LCT on cytotoxicity in normal human brain cells is still elusive. This study examined whether LCT affected Ca²⁺ homeostasis and Ca²⁺-related physiology in Gibco® Human Astrocytes (GHA cells), and explored whether BAPTA-AM (1,2-bis(2-aminophenoxy)ethane-N,N,N'N'-tetraacetic acid), a selective Ca²⁺ chelator, has protective effects on LCT-treated GHA cells. The data show that LCT (10-15 μM) concentration-dependently induced cytotoxicity in both GHA cells and DI TNC1 normal rat astrocytes but only induced intracellular Ca²⁺ concentration ([Ca²⁺]_i) rises in GHA cells. In terms of Ca²⁺ signaling in GHA cells, LCT-induced [Ca²⁺]_i rises were reduced by removing extracellular Ca²⁺ and were inhibited by store-operated Ca²⁺ channel modulators (2-APB, econazole or SKF96365). In Ca²⁺-free medium, pretreatment with the endoplasmic reticulum Ca²⁺ pump inhibitor thapsigargin abolished LCT-induced [Ca²⁺]_i rises. Conversely, incubation with LCT abolished thapsigargin-induced [Ca²⁺]_i rises. Regarding cytotoxicity, LCT evoked apoptosis by regulating apoptotic protein expressions (Bax, BCl-2, cleaved caspase-9/-3). This apoptotic response was significantly inhibited by prechelating cytosolic Ca²⁺ with BAPTA-AM. Together, in GHA cells, LCT induced [Ca²⁺]_i rises by inducing Ca²⁺ entry via store-operated Ca²⁺ channels and Ca²⁺ release from the endoplasmic reticulum. Moreover, BAPTA-AM has a protective effect on inhibiting LCT-activated mitochondrial apoptotic pathway. This study provided new insights into the molecular protective mechanism of LCT-induced cytotoxicity in normal human astrocytes.

Neurodevelopmental consequences of gestational and lactational exposure to pyrethroids in rats

Indiscriminate use of pyrethroids has raised serious health related concerns, especially about their effects on children. The present study was designed to assess the developmental neurotoxicity of two pyrethroids; bifenthrin (BIF) and β-cyfluthrin (CYF) administered at 1/15 of LD₅₀ in rats. Pregnant females were exposed to the test compounds orally throughout gestation and lactation periods. Neonates were weighed and sexed at birth and were observed for any gross abnormality. Growth, viability and weaning indices were calculated during the lactation period. Exposure to both the compounds did not alter the physical developmental parameters viz. eye opening, pinna detachment, and fur appearance. CYF significantly impaired growth and survivability of pups. Behavioral endpoints assessed in neonates (surface righting, pivoting, and negative geotaxis reflex) as well as adults (motor activity and motor coordination) exhibited marked effect of CYF treatment. Administration of BIF to pregnant dams impaired pivoting in neonates. Decreased locomotion in the open-field and impaired rota-rod performance were also witnessed in BIF-exposed animals. Enhanced oxidative stress was seen in corpus striatum, cerebellum, and hippocampus regions of the brain; reduced catalase, superoxide dismutase, and glutathione peroxidase activities were measured in BIF and CYF treated weanlings. Acetylcholinesterase activity was also found to be lowered following administration of both compounds at PND 21. The present results suggest that exposure to pyrethroids during critical periods of growth can induce long term effects on the behavior of animals. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1761-1770, 2016.

Tissue distribution, metabolism and hepatic tissue injury in Chinese lizards (Eremias argus) after a single oral administration of lambda-cyhalothrin

Lambda-cyhalothrin (LCT) is a widely used pyrethroid with neurotoxicity. However, little is known about the toxicokinetics of LCT in reptiles. In this study, the absorption, distribution, metabolism and excretion of LCT in Chinese lizards (Eremias Argus) were determined following a single dose (10 mg kg^-1) treatment. In the liver, brain, gonads and skin, LCT levels peaked within several hours and then decreased rapidly. However, the concentration of LCT gradually increased in the fat tissue. More than 90% of the LCT dose was excreted in the faeces. One LCT metabolite, 3-phenoxybenzoic acid (PBA), was detected in lizard plasma and tissues. PBA preferentially accumulates in the brain and plasma. The half-life of PBA in the brain was 3.2 days, which was 35.4-fold greater than that of LCT. In the plasma, the concentration of PBA was significantly higher than that of LCT. The bioaccumulation of LCT in tissues was enantioselective, and the enantiomeric fractions (EF) ranged from 0.72 to 0.26. The preferential accumulation of enantiomers changed according to exposure time, but the reasons behind this phenomenon were not clear. For pathological analysis, vacuolation of the cytoplasm and large areas of necrosis were observed in the liver sections after 168 h of dosing. The liver tissues exhibited both decreases in the hepatosomatic index and histopathological lesions during the exposure period. In this study, the effect concentration of LCT in lizards was 200-fold lower than its LD₅₀ value used in risk assessments for birds. These results may provide additional information for the risk assessment of LCT for reptiles and indicate that birds may not be an ideal surrogate for reptile toxicity evaluation.

Cytotoxic and genotoxic effects of abamectin, chlorfenapyr, and imidacloprid on CHOK1 cells

The cytotoxicity and genotoxicity of abamectin, chlorfenapyr, and imidacloprid have been evaluated on the Chinese hamster ovary (CHOK1) cells. Neutral red incorporation (NRI), total cellular protein content (TCP), and methyl tetrazolium (MTT) assays were followed to estimate the mid-point cytotoxicity values, NRI50, TCP50, and MTT50, respectively. The effects of the sublethal concentration (NRI25) on glutathione S-transferase (GST), glutathione reductase (GRD), glutathione peroxidase (GPX), and total glutathione content have been evaluated in the presence and absence of reduced glutathione (GSH), vitamin C, and vitamin E. The genotoxicity was evaluated using chromosomal aberrations (CA), micronucleus (MN) formation, and DNA fragmentation techniques in the presence and absence of the metabolic activation system, S9 mix. Abamectin was the most cytotoxic pesticide followed by chlorfenapyr, while imidacloprid was the least cytotoxic one. The glutathione redox cycle components were altered by the tested pesticides in the absence and presence of the tested antioxidants. The results of genotoxicity indicate that abamectin, chlorfenapyr, and imidacloprid have potential genotoxic effects on CHOK1 cells under the experimental conditions.

Protective effects of oat oil on deltamethrin-induced reprotoxicity in male mice

Oats (Avena sativa L.), which are used in foods, are a potential economically viable source of oil. The purpose of this study was to determine the efficiency of oats oil to alleviate oxidative damage of testis induced by deltamethrin, which is a pyrethroid pesticide that exerts a wide range of effects on non-targeted organisms. The reprotoxicity caused by orally administered deltamethrin (DEL) to mice can be effectively antagonized by the beneficial effects of oats oil (OO) as an antioxidant. Thirty-two male albino mice were divided into four equal groups: a control group, a group of mice given deltamethrin (5 mg per kg b.w.), a group administered deltamethrin after receiving oats oil (6 g per kg b.w.), and a group receiving only OO. Exposure to deltamethrin at a dose of 5 mg per kg b.w. per day caused oxidative stress in testis, proven by a decrease in the epididymal sperm count and motility, an increase in the number of abnormal morphologies in spermatozoa and a significant increase of lipid peroxidation (LP) in the testis when compared to control animals. Co-administration of oats oil to the DEL-treated mice ameliorated the testicular biochemical parameters as well as the histological impairments in testis. We concluded that oats oil ameliorated the toxic effects of deltamethrin in testis explored by reduced LP and improved total sperm density, motility and morphology in mice spermatozoa, suggesting its role as a potential antioxidant.

Antioxidant properties of Pelargonium graveolens L'Her essential oil on the reproductive damage induced by deltamethrin in mice as compared to alpha-tocopherol

Background

Exposure to the pyrethroid pesticide deltamethrin has been demonstrated to exert a wide range of effects on non-targeted organisms. The beneficial effects of geranuim essential oil (EO) as an antioxidant has been assessed in deltamethrin (DL) orally administered mice by studying whether the reprotoxicity caused by deltamethrin can be effectively combated with the geranium oil and the effects were compared to vitamin E, as the standard reference drug.

Result

Sixty male albino mice were divided into six equal groups: a control group, a group of mice was given deltamethrin (5 mg/kg b.w.), two groups were administered deltamethrin after having given geranium essential oil (67 mg/kg b.w.) or vitamin E (Vit E) (100 mg/kg b.w.), and two groups received only EO of geranium or Vit E. When compared to control, a dose of deltamethrin 5 mg/kg/day causes a decrease in the epididymal sperm count motility and viability and an increase in the number of abnormal morphology in spermatozoa. DL-exposed mice showed a significant increase of lipid peroxidation (LPP) in the testis compared to control animals.

Conclusion

Essential oil of geranium prevented testicular oxidative damage explored by reduced LPP and improved total sperm motility, viability and morphology in mice spermatozoa. Our study showed a positive influence of geranium essential oil in the animal male reproductive system similar than that of Vit E.

Methodologies, bioindicators, and biomarkers for assessing gender-related differences in wildlife exposed to environmental chemicals

Male and female organisms may have significant differences in their exposure, toxicokinetics, and response to chemicals, but gender effects have received relatively little attention, often viewed as a confounder rather than of primary importance. In this paper, we examine some of the key issues and methodologies for incorporating gender in studies of the effects of chemicals on wildlife, and explore bioindicators and biomarkers of gender effects. Examining gender-related differences in response to chemicals is complicated in wildlife because of the vast array of species, and differences in niches, lifespans, reproductive cycles and modes, and population dynamics. Further, organisms are more at risk in some ecosystems than others, which may increase the magnitude of effects. Only by studying wild animals, especially native species, can we truly understand the potential impact of gender-specific effects of chemical exposure on populations. Several factors affect gender-related differences in responses to chemicals, including exposure, age, size, seasonality, and genetic and phenotypic variation. There are clear examples where gender-related differences have had significant effects on reproductive success and population stability, including destabilization of gamete release in invertebrates, and alterations of endocrine and neuroendocrine system functioning in vertebrates. A wide range of new technologies and methods are available for examining gender-related differences in responses to chemicals. We provide examples that show that there are gender-related differences in responses to chemicals that have significant biological effects, and these gender-related differences should be taken into account by scientists, regulators, and policy makers, as well as the public.