Cypermethrin Research Articles

Detection of toxic cypermethrin pesticides in drinking water by simple graphitic electrode modified with Kraft lignin@Ni@g-C3N4 nano-composite.

The detrimental effects of widespread pesticide application on the health of living organisms highlight the urgent need for technological advancements in monitoring pesticide residues at trace levels. This study involves the synthesis of a distinctive sensing material, KL@Ni@g-C3N4, which comprises nanocomposites of graphitic carbon nitride with Kraft lignin and nickel. The prepared samples were characterized using FT-IR, PXRD, TEM, SEM, and EDX techniques. The KL@Ni@g-C3N4 nanocomposite was drop-cast on a graphite electrode. Subsequently, this fabricated electrode was used to detect cypermethrin (CYP) residues in drinking water. The redox properties of the fabricated sensors were evaluated using electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). The limit of detection (LOD) of the fabricated sensor was determined to be 0.026 μg mL-1, which is below the maximum residual limits of CYP in the environment (0.5 μg mL-1) and within the acceptable range for food products (∼0.05 to 0.2 μg mL-1). Therefore, this study proposes a promising alternative to conventional methods for detecting pesticides in drinking water.

Hepatoprotective Effect of Alcoholic Extract of Ficus carica Leaves ‎Against ‎‎Cypermethrin-Induced Liver Toxicity in Male Albino Rats

Cypermethrin (CYP), a synthetic pyrethroid, is recognized for its insecticidal properties but ‎poses potential risks of hepatotoxicity. In traditional medicine, Ficus (F.) carica (common ‎fig) leaves have historically been used for various therapeutic applications. This study ‎aimed to evaluate the hepatoprotective effect of the methanolic extract of F. carica‎‎ leaves ‎against CYP-induced liver damage in adult male albino rats (Rattus norvegicus). The ‎animals (n=30), 8-12 weeks old ‎and weighing 200-250 g‎, were randomly divided into five ‎experimental groups (n=6) and treated as follows: the negative control group received ‎distilled water; the CYP-Only group was exposed to 4.74 mg/kg BW for 45 days; the ‎CYP+post-treatment group received the same CYP dosage followed by F. carica‎‎ methanolic ‎leaf extract at 500 mg/kg BW orally for two weeks; the pre-treatment+CYP group received ‎ ‎F. carica‎‎ methanolic leaf extract at 500 mg/kg BW orally for two weeks followed by CYP ‎exposure for 45 days; and the F. carica‎‎ extract-Only group was administered the methanolic ‎leaf extract at 500 mg/kg BW orally for two weeks. At the end of the experiment, serum and ‎liver samples were analyzed for biochemical and histopathological changes. CYP-Only ‎exposed group showed significantly increased serum alanine aminotransferase (ALT) and ‎alkaline phosphatase (ALP) and caspase-3 levels (P<0.05). Histopathological examination ‎in group exposed CYP only revealed liver damages as evidenced by central vein congestion, ‎scattered perivascular mononuclear cell infiltration, prominence of ‎Kupffer cells, nuclear ‎pyknosis, and severe hepatocytic necrosis. Treatment with F. carica‎‎ leaf extract, either ‎before or after CYP exposure, as well as solely with F. carica‎‎ leaf ‎‎extract, ameliorated both ‎the biochemical and histological indices of liver ‎damage. The findings suggest that the ‎methanolic extract of F. carica‎‎ leaves provides promising hepatoprotective effects against ‎CYP-induced liver damage in albino rats, likely via its antioxidative properties‎‎.

Cypermethrin: An Emerging Pollutant and Its Adverse Effect on Fish Health and some Preventive Approach-A Review.

Pesticides are substance that are used to manage pests, such as aquatic weeds, plant diseases and insects. It has been shown that these substances are highly hazardous to fish as well as other organisms that are part of the food chain. The presence of cypermethrin in food and groundwater has raised environmental concerns, there is a need to develop economical, rapid, and reliable techniques that can be used for field applications Many studies have shown that Cypermethrin (CYP) can cause toxic effect in various animals including fishes. But the molecular mechanism behind the toxicity mediated Cypermethrin (CYP) at genome levels and proteome levels is still need to be studied. However, there is a gap in emerging and undeveloped nations to begin to use these methods and several other recently developed approaches to inhibit the negative consequences and enhance health which may be profitable. The toxicological information currently available might be used to gain a clear understanding of the possibilities of these synthetic pyrethroid insecticides causing various health hazards to environmental and provides insight for future research evaluating the toxic effects of pyrethroid insecticides. This present review article is concerned with the toxicological effects of pesticides and a brief overview of sources, classification of pesticides with an emphasis on the effects of Cypermethrin (CYP) on fish as well mode of toxicity and the mechanism of action (CYP) and toxicity signs in several fish species have been illustrated. The primary controls and appropriate preventive measures that must be adopted are also discussed.

Ascorbate and Alpha-Tocopherol Mitigate Toxic Pathological Changes in Adult Wistar Rats Exposed to Cypermethrin

Excessive and uncontrolled use of pyrethroids such as cypermethrin (CYP) for pest control in Nigeria can adversely affect humans. This study investigated the oxidative stress response to cypermethrin exposure as well as the therapeutic effect of ascorbate and alpha-tocopherol when administered singly or co-administered. Additionally, the lungs and heart of the exposed animals were histologically assessed for cypermethrin-induced cytopathic changes. Twenty-five adult male Wistar rats weighing between 180 – 200g were randomly assigned to five groups of five animals each. Group I was the unexposed control group, while Group II was the exposed untreated group that was orally administered Cypermethrin at a dose of 10mg/kg/bw. Group III – V was given cypermethrin at standard doses of 10mg/kg/bw, and orally administered with ascorbate (5000mg/kg/bw), alpha-tocopherol (3000mg/kg/bw) and co-administration of ascorbate and alpha-tocopherol (5000mg/kg/bw and 3000mg/kg/bw) respectively. Animals were euthanized after 28 days, and samples were processed for histological and biochemical studies. The results showed elevated malondialdehyde (MDA) levels with a concurrent marked decrease in superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) activities (p<0.05) in the cypermethrin-exposed untreated rats, while histopathological findings revealed inflammation and congestion in the organs studied. The co-administrative treatment with ascorbate and alpha-tocopherol better restores biochemical parameters than their single administration. Conclusively, co-administration of ascorbic acid and alpha-tocopherol ameliorates cypermethrin-induced oxidative damage better than single administration, which may be due to their synergistic antioxidant properties.

Investigating the effect of pH on the interaction of cypermethrin with human serum albumin: Insights from spectroscopic and molecular dynamics simulation studies

To efficiently combat the negative consequences of the utilization of pesticides and hazardous substances with biomolecules, it is crucial to comprehend the features of the corresponding compounds. In this study, interactions between cypermethrin (CYP) and HSA at neutral and acidic pH were investigated using a set of spectroscopic and computational tools, such as UV/VIS's absorption spectroscopy, fluorescence, Fourier-transform infrared (FTIR) spectroscopy, molecular docking, and molecular dynamics. Furthermore, the effect of CYP on the HSA thermal stability was investigated. The increase in the CYP concentration at acidic and neutral pH resulted in static HSA fluorescence quenching. In the interaction between HSA and CYP at both pH, increasing the temperature led to a decrease in the Stern-Volmer quenching constant and the binding constant. We also revealed that with increasing CYP concentration, the melting temperature of HSA increases at both pH values.

Co-exposure to polystyrene microplastics and cypermethrin enhanced the effects on hepatic phospholipid metabolism and gut microbes in adult zebrafish

Microplastics (MPs) can absorb environmental pollutants from the aquatic environment to cause mixed toxicity, which has received widespread attention. However, studies on the joint effects of MPs and insecticides are limited. As one of the most widely used pyrethroids, there was a large amount of residual cypermethrin (CYP) in water due to insufficient decomposition. Here, adult female zebrafish were exposed to MPs, CYP, and their mixtures for 21 days, respectively. After exposures, the MPs and CYP caused tissue damage to the liver. Hepatic triglyceride (TG) level increased significantly after MPs + CYP exposure, and the expression of genes about glycolipids metabolism was significantly altered. Furthermore, metabolome results suggested that MPs + CYP exposure resulted in increased content of some glycerophospholipid, affecting phospholipid metabolism-related pathways. In addition, through 16 s rDNA sequencing, it was found that MPs + CYP led to significant changes in the proportion of dominant phyla. Interestingly, Cetobacterium which increased in CYP and the co-exposure group was positively correlated with most lipid metabolites. Our results suggested that co-exposure to MPs and CYP enhanced the disturbances in hepatic phospholipid metabolism by affecting the gut microbial composition, while these changes were not observed in separate treatment groups. These results emphasized the importance of studying the joint toxicity of MPs and insecticides.

Sugeno fuzzy inference system modeling and DFT calculations for the treatment of pesticide-laden water by newly developed arginine functionalized magnetic Mn-based metal organic framework.

The uncontrolled utilization of pesticides poses a significant risk to the environment and human health, making its management essential. In this regard, a new arginine functionalized magnetic Mn-based metal-organic framework (Arg@m-Mn-MOF) was fabricated and assessed for the removal of cypermethrin (CYP) and chlorpyrifos (CHL) from aqueous system. The Arg@m-Mn-MOF was characterized by scanning electron microscopy, energy dispersive X-ray, Fourier transform infrared spectroscopy, X-ray diffraction, and Brunauer-Emmett-Teller analysis. Various parameters were optimized in a series of batch experiments and the following conditions were found optimal: pH: 4 and 5, contact time: 20min, adsorbent dosage: 0.6 and 0.8g L-1 with initial concentration: 10mg L-1 and temperature: 298K for CYP and CHL, respectively. The composite attained a maximum removal capacity of 44.84 and 71.42mgg-1 for CYP and CHL, respectively. The elucidated data was strongly fitted to the pseudo-second-order model of kinetics (R2 > 0.98) and Langmuir isotherm (R2 > 0.98). Based upon 350 experimental datasets obtained from batch studies and interpolated data, the adsorption capacity of the adsorbent was elucidated with R2 > 0.97 (CHL) and > 0.91 (CYP). The adsorption energy (- 11.67kcalmol-1) calculated by Gaussian software suggests a good interaction between arginine and CHL through H-bonding. The present study's findings suggested the prepared Arg@m-Mn-MOF as a promising adsorbent for the efficient removal of pesticides from agriculture runoff.

HEALTH RISK ASSESSMENT OF PYRETHROID PESTICIDE RESIDUES IN PRODUCES AND SOILS IN A FARMLAND FROM ABEOKUTA, OGUN STATE, NIGERIA

Despite being useful in pest control, pyrethroids have been found to bioaccumulate in aquatic organisms and in human breast milk and research has shown that pyrethroids are neurotoxic, affect reproductive health and have ability to interfere with the immunological and endocrine systems, they also function as cancer precursors. This study sought to determine the amounts of pyrethroid residue in the soils and some of the most popular food crops, yam and cassava, in order to evaluate food safety using Gas chromatography Mass spectrometry (GC-MS). Cyfluthrin, alpha cypermethrin and beta cypermethrin are pyrethroids found in all the yams and cassava and soils analysed in this study and their values ranged from 9.98mg/kg to 14.45mg/kg in yam farm soil, 8.1mg/kg to 18.46mg/kg in yam samples, 10.25mg/kg to 14.94mg/kg in cassava samples and 6.13mg/kg to 30.6mg/kg in cassava farm soils. The pyrethroid with the highest residue levels in all the samples taken was beta cypermethrin. The health risk was assessed by calculating bioaccumulation factor and comparing Acceptable Daily Intake (ADI) with Food and Agricultural Organization (FAO) recommendations. Bioaccumulation factor of the foods analysed ranged from 0.49 (beta cypermethrin) to 1.68 (alpha cypermethrin) in cassava and 0.56 (cyfluthrin) and 1.07 (alpha cypermethrin) in yams. The pyrethroid residues discovered in the foods in this study exceeded the ADI of pesticides established by FAO, 0.02mg/kg per day; a significant health risk indication. Care should therefore be taken when using these pesticides and consumption of food exposed to pesticides should be discouraged.

Exploring the combined interplays: Effects of cypermethrin and microplastic exposure on the survival and antioxidant physiology of Astacus leptodactylus

Plastic waste and micro/nanoplastic particles pose a significant global environmental challenge, along with concerns surrounding certain pesticides' impact on aquatic organisms. This study investigated the effects of microplastic particles (MPPs) and cypermethrin (CYP) on crayfish, focusing on biochemical indices, lipid peroxidation, oxidative stress, hematological changes, and histopathological damage. After determining the LC50–96 h value (4.162 μg/L), crayfish were exposed to sub-lethal concentrations of CYP (1.00 ppb (20%) and 2.00 ppb (50%)) and fed a diet containing 100 mg/kg MPPs for 60 days. Hemolymph transfusion and histopathological examinations of the hepatopancreas were conducted. The results showed significant alterations in crayfish. Total protein levels decreased, indicating protein breakdown to counteract contaminants, while total cholesterol and triglyceride levels declined, suggesting impaired metabolism. Glucose levels increased in response to chemical stress. The decline in total antioxidant capacity highlighted the impact of prolonged xenobiotic exposure and oxidative stress, while increased CAT, SOD, and MDA activities helped mitigate oxidative stress and maintain cellular homeostasis. The elevated total hemocyte count, particularly in semi-granular cells, suggests their active involvement in the detoxification process. Further research is needed to fully understand the implications of these effects.

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-1β (IL-1β), 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.Graphical

Effect of pH on the structure and properties of pesticide intercalated into montmorillonite modified by zwitterionic surfactant

DCB (OA, DSB, SB)-MMT complexes were prepared by incorporating zwitterionic surfactants dodecyl dimethyl carboxylbetaine (DCB), N,N-dimethyldodecylamine N-oxide (OA), dodecyl dimethyl sulfobetaine (DSB) and 3-sulphonyl hexadecyldimethylamine (SB) into montmorillonite (MMT). The complexes were characterized by XRD, FT-IR, TGA/DTA and SEM, TEM. Results indicated that the interlayer distances of OA (DSB)-MMT depended on surfactant content and pH value, while those of DCB (SB)-MMT were only related to the surfactant content. The different thermal decomposition processes of complexes were closely related with pH values. Then the pesticide (lambda-cyhalothrin (LCT) or beta-cypermethrin (BCT)) - DCB(SB) micelles were incorporated into the galleries of LCT/DCB-MMT and BCT/SB-MMT hybrids. The basal spaces of LCT/DCB-MMT and BCT/SB-MMT were 4.03 and 4.64 nm, which were larger than those of DCB-MMT and SB-MMT, respectively. The pesticide intercalation was further confirmed by FTIR and TGA/DTA. Furthermore, the release behaviors of BCT (LCT) from the hybrids were compared and analyzed. The pesticide hybrids have the slow release property due to the strong interaction between DCB(SB) and MMT. The pseudo second-order and parabolic diffusion models can be well used to fit the release data. The present study is conducive to the application of MMT as good carriers of pesticide delivery system.

Identification and characterization of long non-coding RNA (lncRNA) in cypermethrin and chlorpyrifos exposed zebrafish (Danio rerio) brain

Pesticides, such as cypermethrin (CYP) and chlorpyrifos (CPF), are widely used around the world and are known to cause toxicological effects in the brains of fish and other non-target organisms. Long non-coding RNAs (LncRNAs) are a new class of non-coding RNAs that are highly expressed in the brain and play crucial roles in brain function by regulating gene expression. Many studies have investigated the toxic effects of CYP and CPF on the brain. However, no study has been conducted on the relationship between LncRNAs and the toxicity caused by these chemicals. Therefore, this study aimed to determine changes in the lncRNA expression profile in the brains of fish exposed to CYP and CPF. Out of a total of 482 lncRNAs that were differentially expressed between control and CPF groups, 53 were found to be up-regulated, and 429 were down-regulated. Similarly, among the 200 lncRNAs differentially expressed between the control and CYP groups, 71 were up-regulated, and 129 were down-regulated. Additionally, 268 differentially expressed lncRNAs were identified between CYP and CPF groups, with 240 being up-regulated and the rest being down-regulated. In addition, LncRNAs expressed from fish brains exposed to CYP and CPF were found to regulate multiple signaling pathways, including MAPK, FoxO, PPAR, TGF-β, and Wnt signaling pathways.

Analysis of the α-CYPERMETHRIN biodegradation by Klebsiella pneumoniae YH43

Cypermethrin (CYP) is an insecticide pyrethroid used in the agriculture for its broad-spectrum activity. However, recent studies have shown the accumulation of CYP in soil, and water and a high toxicity against different species, including humans. On the other hand, the use of bacteria in bioremediation represents an eco-friendly alternative for the removal of different xenobiotics. In this study, the aim was to isolate and identify bacteria from agricultural soils to determine their ability to tolerate and biodegrade CYP. Additionally, some metabolites of the CYP biodegradation were detected by ultra-performance liquid chromatography with mass spectrometry (UPLC-MS). Klebsiella pneumoniae YH43 isolate used CYP as a carbon source, degrading 87.55 % at a concentration of 100 mg/L. α-cyano-3-phenoxybenzyl alcohol and cis,trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane carboxylate were identified as the main metabolites in the pathway of the CYP biodegradation. These results suggest that K. pneumoniae YH43 has the potential to be used in the bioremediation of contaminated soils with CYP.

Assessing the susceptibility and efficacy of traditional neurotoxic (pyrethroid) and new-generation insecticides (chlorfenapyr, clothianidin, and pyriproxyfen), on wild pyrethroid-resistant populations of Anopheles gambiae from southern Benin.

The objective of this study was to determine the susceptibility of wild Anopheles gambiae sensu lato (s.l.) from southern Benin to the new insecticides (chlorfenapyr (CFP), pyriproxyfen (PPF), and clothianidin (CTD)) and assess the efficacy of insecticide-treated bed nets (ITNs) that contain these new products. Wild An. gambiae from the Benin communes of Allada, Ifangni, Akpro-Missérété, and Porto-Novo were tested for their susceptibility to CFP and PPF using the WHO bottle tests, and pyrethroids (alpha-cypermethrin, deltamethrin, and permethrin) and CTD using WHO tube tests. WHO cone tests were used to evaluate the efficacy of Interceptor® (which contains alpha-cypermethrin (ACM) only), Interceptor® G2, (CFP + ACM), and Royal Guard® nets (PPF + ACM). The ovaries of blood-fed An. gambiae from Ifangni exposed to a new PPF net were dissected, and egg development status was examined using Christopher's stages to determine the fertility status of the mosquitoes. Using a standardized protocol, the oviposition rate and oviposition inhibition rate were calculated from live blood-fed An. gambiae placed in oviposition chambers after exposure to PPF. In all four mosquito populations, pyrethroid mortality ranged from 5 to 80%, while chlorfenapyr and clothianidin mortality ranged from 98 to 100%. At Ifangni, all mosquitoes exposed to Royal Guard® nets were infertile (100%) while the majority (74.9%) of mosquitoes exposed to Interceptor® nets had fully developed their eggs to Christopher's stage V. The oviposition inhibition rate after exposure of the mosquitoes to the PPF was 99% for the wild population of An. gambiae s.l. and the susceptible laboratory strain, An. gambiae sensu stricto (Kisumu). The results of this study suggest that pyrethroid-resistant An. gambiae from the selected communes in southern Benin are susceptible to chlorfenapyr, clothianidin, and pyriproxyfen. In addition, based on bioassay results, new and unused Interceptor® G2 and Royal Guard® nets were effective on Ifangni's mosquito populations. Despite the availability of new effective insecticides, continued vigilance is needed in Benin. Therefore, monitoring of resistance to these insecticides will continue to periodically update the Benin national insecticide resistance database and management plan.

In Vitro Biofilm-Mediated Biodegradation of Pesticides and Dye-Contaminated Effluents Using Bacterial Biofilms.

Overuse of pesticides in agricultural soil and dye-polluted effluents severely contaminates the environment and is toxic to animals and humans making their removal from the environment essential. The present study aimed to assess the biodegradation of pesticides (cypermethrin (CYP) and imidacloprid (IMI)), and dyes (malachite green (MG) and Congo red (CR)) using biofilms of bacteria isolated from pesticide-contaminated soil and dye effluents. Biofilms of indigenous bacteria, i.e., Bacillus thuringiensis 2A (OP554568), Enterobacter hormaechei 4A (OP723332), Bacillus sp. 5A (OP586601), and Bacillus cereus 6B (OP586602) individually and in mixed culture were tested against CYP and IMI. Biofilms of indigenous bacteria i.e., Lysinibacillus sphaericus AF1 (OP589134), Bacillus sp. CF3 (OP589135) and Bacillus sp. DF4 (OP589136) individually and in mixed culture were tested for their ability to degrade dyes. The biofilm of a mixed culture of B. thuringiensis + Bacillus sp. (P7) showed 46.2% degradation of CYP compared to the biofilm of a mixed culture of B. thuringiensis + E. hormaechei + Bacillus sp. + B. cereus (P11), which showed significantly high degradation (70.0%) of IMI. Regarding dye biodegradation, a mixed culture biofilm of Bacillus sp. + Bacillus sp. (D6) showed 86.76% degradation of MG, which was significantly high compared to a mixed culture biofilm of L. sphaericus + Bacillus sp. (D4) that degraded only 30.78% of CR. UV-VIS spectroscopy revealed major peaks at 224 nm, 263 nm, 581 nm and 436 nm for CYP, IMI, MG and CR, respectively, which completely disappeared after treatment with bacterial biofilms. Fourier transform infrared (FTIR) analysis showed the appearance of new peaks in degraded metabolites and disappearance of a peak in the control spectrum after biofilm treatment. Thin layer chromatography (TLC) analysis also confirmed the degradation of CYP, IMI, MG and CR into several metabolites compared to the control. The present study demonstrates the biodegradation potential of biofilm-forming bacteria isolated from pesticide-polluted soil and dye effluents against pesticides and dyes. This is the first report demonstrating biofilm-mediated bio-degradation of CYP, IMI, MG and CR utilizing soil and effluent bacterial flora from Multan and Sheikhupura, Punjab, Pakistan.

Functional characterization of SlGSTD3 and SlGSTD4 associated with phoxim and chlorpyrifos resistance in Spodoptera litura

Glutathione S-transferases (GSTs) is one of the main detoxification enzyme systems in insects and play important roles in insecticide resistance by direct metabolism, sequestration and antioxidant activity. Several GSTs genes in Spodoptera litura, a polyphagous agricultural pest, have been demonstrated to be overexpressed and involved in organophosphates and pyrethroids resistance. Previous studies have indicated the significant overexpression of two delta class GSTs genes (SlGSTd3 and SlGSTd4) in organophosphates and pyrethroids resistant populations. Here, they were heterologous expressed, and their metabolism activity and antioxidant activity were determined. Results indicated that the recombinant protein SlGSTD3 and SlGSTD4 both showed metabolism activity to phoxim and chlorpyrifos, but not to fenvalerate, cyhalothrin or beta cypermethrin. The metabolism activity of SlGSTD3 to phoxim and chlorpyrifos is higher than that of SlGSTD4. The recombinant vector of SlGSTD3 and SlGSTD4 both showed antioxidant activity after exposure to cumene hydroperoxide. Further modeling and docking analysis indicated that the 3D structure of SlGSTD3 and SlGSTD4 were well shaped for phoxim and chlorpyrifos, and the binding affinity for phoxim was stronger than that of chlorpyrifos. Our work provides evidence that SlGSTd3 and SlGSTd4 both play roles in phoxim and chlorpyrifos resistance in S. litura.

The protective effect of caffeic acid phenethyl ester in the nephrotoxicity induced by α-cypermethrin.

Alpha cypermethrin (α-CYP) is an insecticide, a member of the group of synthetic pyrethroid pesticides. This study aims to assess the histopathological and biochemical subacute effects of α-CYP on the renal tissues of 48 male Spraque-Dawley adult rats. In this study, the rats were divided into six groups: control, α-CYP (10 mg kg-1), α-CYP (20 mg kg-1), caffeic acid phenethyl ester (CAPE) (10 µmol kg-1), α-CYP + CAPE (10 mg kg-1), and α-CYP + CAPE (20 mg kg-1) groups. The percentage of weight gain was found to be dose-dependent on α-CYP in all groups. As a result of exposure, the normal histological structure of renal tissue was also observed in the control and CAPE groups, while glomerular atrophy and haemorrhage, enlargement of Bowman capsule, glomerular lobulation, and degeneration in distal and proximal tubules were noted in the α-CYP-treated groups with an increased frequency and severity in parallel with the dose increase. Although the severity and intensity of lesions decreased in the α-CYP + CAPE groups, they were statistically insignificant (p > 0.05). A decrease in the antioxidant parameter levels and an increase in oxidant parameters were observed in parallel with the negative effects of the antioxidant system in the α-CYP-treated groups. The groups exposed to CAPE in combination with α-CYP exhibited a therapeutic trend towards normalization in biochemical parameters due to the antioxidant character of CAPE. However, considering the statistical difference between the groups treated with α-CYP alone and CAPE alone, it was observed that the therapeutic features of those chemicals were not robust.

Endocrine disruptive toxicity of cypermethrin in Labeo catla: Involvement of genes and proteins related to the HPG axis

Cypermethrin (CYP) is a synthetic pyrethroid abundantly used in agriculture and aquaculture. It is an established potent endocrine disruptor to fish, yet the molecular mechanism behind its reproductive toxicity remains unclear. In this study, fish Labeo catla (Catla) was exposed to environmentally relevant concentration of CYP (0.7 μg/L) and 0.14 μg/L for 30 days. The changes in circulating sex steroids, genes, and hormones linked to the hypothalamic-pituitary-gonadal (HPG) axis, stress response and associated histological alterations were studied. Significant decline (P < 0.05) in serum 17 beta (β) estradiol (E2), 11 ketotestosterone (11-KT), and brain (FSH and GnRH) were observed in 0.7 μg/L dose of CYP. These effects may be due to the down-regulated expression of the upstream genes of the HPG axis i.e. Kiss 1 and Kiss 2, which further downregulates the expression of the GnRH gene. The decreased level of E2 and 11-KT also affects the vitellogenin (Vtg) gene expression, reducing the production of Vtg, a crucial protein for ovarian development. Principal component analysis (PCA) revealed the relationship between CYP and the biosynthesis of sex steroids. The toxic effect of CYP was also visible in antioxidant enzyme assay and related histological alterations. Overall, the study elucidated that long-term exposure to CYP, even at an environmentally relevant dose, may affect reproductive potential and fish recruitment. The study provides important insights into molecular mechanisms underlying CYP-induced endocrine disruption in fish, and it also raises questions about CYP's potential toxicity at environmentally relevant concentration in terms of understanding ecological risk.

Acaricides resistance in Rhipicephalus microplus and expression profile of ABC-transporter genes in the sampled populations

Currently, livestock owners manage tick infestations using chemicals, but the method is increasingly losing effectiveness as resistant tick populations have established in the field conditions. Thus, to develop effective tick management strategies, monitoring of resistance in most predominant tick species, Rhipicephalus microplus was targeted. The ticks were collected from eleven districts of Madhya Pradesh and one district of Punjab and tested against deltamethrin (DLM), cypermethrin (CYP), coumaphos (CMP), ivermectin (IVM) and fipronil (FIP), through adult immersion and larval packet tests. The field isolates were highly resistant to DLM [Resistance factor (RF) = 3.98–38.84]. Against CYP, resistance was observed in BWN (Barwani; RF = 2.81) and MND (Mandsaur; RF = 3.23) isolates. Surprisingly, most of the isolates were susceptible to CMP (0.34–1.58). Emerging level of resistance against IVM (1.05–4.98) and FIP (0.40–2.18) was also observed in all the isolates. Significantly elevated production of esterases (p < 0.01) was 90% correlated with RF of DLM while no positive correlation between production of monooxygenase and Glutathione S-transferase with RF to DLM was noted. Multiple sequence analysis of S4-5 linker region of the sodium channel gene of all the isolates revealed a point mutation at 190th position (C190A) which is associated with DLM resistance. Treatment of resistant LDH (Ludhiana) isolate with IVM resulted in upregulation of RmABCC2 gene and insignificant upregulation of RmABCC1 and RmABCB10 genes indicating the probability of linking IVM resistance with over-expression of RmABCC2 gene. The possible tick management strategies are discussed.

Evolution of acaricide resistance of Rhipicephalus decoloratus on commercial farms in South Africa.

The development of tick resistance to chemical control plays a major role in the increasing global economic impact of ticks on cattle farming. Reports on acaricide resistance of Rhipicephalus decoloratus, endemic to Africa and South Africa, are relatively few compared to the closely related and globally distributed Rhipicephalus microplus. In South Africa, ectoparasite control became the sole responsibility of each commercial producer when compulsory dipping was phased out from 1984. Different acaricidal management strategies resulted in the simultaneous development of resistance to various acaricide groups. The establishment of a Pesticide Resistance Testing Facility provided the opportunity to test Rhipicephalus (Boophilus) populations, submitted from all over South Africa, for resistance where failure of chemical control was experienced. The number of populations resistant to cypermethrin (CM) was significantly higher than those tested as resistant to amitraz (AM), or chlorfenvinphos (CFVP). No significant difference was found between the number of populations resistant to AM and CFVP. The evolution of R. decoloratus resistance at the end of a 12year period indicated a stable but high prevalence of 90% overall resistance to CM. The same trend was seen for AM-resistant R. decoloratus populations but at a lower level of just over 40%. In contrast, CFVP resistant R. decoloratus populations showed a decreasing trend with near-total reversion to susceptibility. Multi-resistance was present in more than 50% of populations tested with the highest incidence in the Eastern Cape, KwaZulu-Natal, and Western Cape provinces.