Permethrin Treatment Research Articles

The association between knockdown resistance and treatment outcome of 1% permethrin lotion in head lice infestations in Nonthaburi province, Thailand.

Head lice infestations significantly impact schoolchildren, with permethrin being the primary treatment. The escalation in the prevalence of the knockdown resistance (kdr) mutation, potentially affecting treatment efficacy, is highly concerning. This study examined head lice infestation prevalence, the efficacy of 1% permethrin lotion, kdr mutation frequency, and the association between kdr genotype and permethrin treatment outcomes in schoolchildren in Nonthaburi province, Thailand. Participants and lice samples were collected from six primary schools using cluster sampling. Clinical outcomes and adverse events were assessed on days 7 and 14 post-treatment. Kdr mutations (T917I) in head lice samples were analyzed using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. Head lice infestation prevalence was 6.1%, with a kdr mutation frequency of 63.2% and a permethrin cure rate of approximately 50%. Multivariate regression analysis revealed the association between kdr genotype and clinical response to permethrin treatment (Odds Ratio (OR) = 13.15, p = 0.005). The presence of resistance genes hinders the cure rate (presence 35.9% versus absence 85.7%). These findings highlight the importance of the kdr genotype in predicting permethrin treatment responses in head lice infestations. Furthermore, in regions with documented reduced permethrin efficacy and a high prevalence of kdr mutations, alternative non-pyrethroid-based pediculicides should be considered. This research could help improve the control of head lice infestations, especially in problematic areas of Thailand.

Understanding Perceptions and Experiences on Acceptability of Oral Ivermectin, Topical Permethrin, and their Combination in the Treatment of Adult Filipino Patients with Scabies: A Multiple Case Study.

Oral ivermectin, a broad-spectrum anti-parasitic drug, alone or in combination with permethrin, may be a cheaper and more convenient alternative drug to topical permethrin alone in the treatment of classic scabies. There are no previous studies on the treatment acceptability of the three interventions among individual patients with scabies in the Philippines.The purpose of this study was to understand the experiences and perceptions on treatment acceptability for oral ivermectin, topical permethrin or combination treatment among patients with scabies using the multiple-case study approach. We conducted a qualitative multiple case study among adult Filipino patients with classic scabies who were prescribed oral ivermectin, topical permethrin or its combination at a government tertiary hospital dermatology outpatient clinic from December 2022 to September 2023. Semi-structured interviews were used as the primary source of data and analyzed together with chart reviews, Dermatology Life Quality Index (DLQI) scores, and clinical images. Interviews were transcribed, coded, and triangulated with other secondary data. A three-person research team employed a reflexive and iterative process of familiarization, coding, and thematic analysis using a modified Theoretical Framework of Acceptability (TFA) to generate case descriptions, within-case analyses, and cross-case syntheses. The acceptability of scabies treatments (permethrin, ivermectin, and combination therapy) was generally positive. Permethrin, used in three patient cases, was generally perceived as effective but itch relief varied. The burden of whole-body application of permethrin was context-dependent, influenced by living arrangements and family support. Perceived affordability of permethrin was linked to socioeconomic status. Ivermectin, used by one patient case, was perceived as highly effective with no side effects. Its single dose use did not interfere with patient routine. Combination therapy was also considered effective but potential antagonistic effects and the cost of adding permethrin made it less preferred. Reluctance in taking oral pills was noted. All patients valued medical advice and deferred to their physicians for treatment decisions. All three treatment options were considered effective and safe. Patients generally preferred permethrin over oral ivermectin due to its topical nature and perceived lower side effects. However, affordability and logistical challenges, especially for large households and low-income families, were noted with permethrin. Oral ivermectin elicited hesitation due to its controversial role in COVID-19 and veterinary use. Concerns about added costs and potential antagonism in combination therapy were raised. Despite these considerations, patients ultimately relied on physicians for treatment decisions. This study underscores the importance of understanding patient perspectives, experiences, and the patient-physician relationship in choosing scabies interventions. Addressing patient concerns, providing education, and ensuring ease of use and affordability can enhance treatment acceptability and adherence for better outcomes.

Scabies in a Preterm Infant Younger than 2 Months: What Do We Have?

Objective – To present a case of scabies in a preterm neonate treated with an off-label treatment (oral ivermectin) without any adverse effects.Case Report – A preterm female neonate (29+3 weeks of gestation) was diagnosed with scabies at 35 days of life (34+3 weeks of corrected gestational age), after her parents had been diagnosed, having been admitted at birth to the neonatal unit of a tertiary hospital. Treatment was initiated with topical off-label permethrin 5%, with the informed consent of the parents. Concomitantly with the patient, the parents received treatment with permethrin 5% and oral ivermectin on days 0, 7, 14 and 21 after diagnosis. No adverse effects resulting from the use of these treatments were reported. On physical examination, active lesions due to scabies were still observed two weeks after permethrin treatment, so it was decided to re-administer the treatment with topical 5% permethrin on days 0 and 14, associated with oral Ivermectin at 200μg/kg on days 0 and 7. The treatment was administered to the patient and her entire family. Fourteen days after completion of ivermectin treatment, the patient presented with complete resolution. Conclusion – After our experience with this case, and given the increasing prevalence of scabies in our environment, we propose that ivermectin is a useful alternative in the treatment of scabies in this age group; however, larger series of patients are needed to establish a recommendation in this regard, evaluating its risks and benefits.

Failure of scabies treatment: a systematic review andmeta-analysis.

Treatment failure is considered to be an important factor in relation to the increase in scabies incidence over the last decade. However, the regional and temporal differences, in addition to the predictors of therapy failure, are unclear. We aimed to conduct a systematic review of the prevalence of treatment failure in patients with scabies and investigation of associated factors. We searched MEDLINE, EMBASE, CINAHL, Web of Science, Scopus, Global Health and the Cochrane Central Register of Controlled Trials from inception to August 2021 for randomized and quasi-randomized trials, in addition to observational studies that enrolled children or adults diagnosed with confirmed or clinical scabies treated with permethrin, ivermectin, crotamiton, benzyl benzoate, malathion, sulfur or lindane, and measured treatment failure or factors associated with treatment failure. We performed a random effects meta-analysis for all outcomes reported by at least two studies. A total of 147 studies were eligible for inclusion in the systematic review. The overall prevalence of treatment failure was 15.2% [95% confidence interval (CI) 12.9-17.6; I2 = 95.3%, moderate-certainty evidence] with regional differences between World Health Organization regions (P = 0.003) being highest in the Western Pacific region (26.9%, 95% CI 14.5-41.2). Oral ivermectin (11.8%, 95% CI 8.4-15.4), topical ivermectin (9.3%, 95% CI 5.1-14.3) and permethrin (10.8%, 95% CI 7.5-14.5) had relatively lower failure prevalence compared with the overall prevalence. Failure prevalence was lower in patients treated with two doses of oral ivermectin (7.1%, 95% CI 3.1-12.3) compared with those treated with one dose (15.2%, 95% CI 10.8-20.2; P = 0.021). Overall and permethrin treatment failure prevalence in the included studies (1983-2021) increased by 0.27% and 0.58% per year, respectively. Only three studies conducted a multivariable risk factor analysis; no studies assessed resistance. A second dose of ivermectin showed lower failure prevalence than single-dose ivermectin, which should be considered in all guidelines. The increase in treatment failure over time hints at decreasing mite susceptibility for several drugs, but reasons for failure are rarely assessed. Ideally, scabicide susceptibility testing should be implemented in future studies.

Permethrin-unresponsive scabies in London, United Kingdom - a wake up call.

Failure to respond to permethrin, the most widely prescribed first-line therapy for scabies, has been increasingly reported in recent years in a number of countries. However, its true scale and relation to verifiable permethrin resistance is currently unknown. We present a case of scabies associated with scabetic nodules in which a lack of response to topical permethrin treatment was evident.

Comparing the efficacy of three methods of permethrin application in pediculosis capitis: A randomized clinical trial.

Pediculosis capitis, also known as head lice, is a common problem that affects individuals of different socio-economic backgrounds. Permethrin is generally considered the first-line treatment option for head lice. The objective of this study was to evaluate and compare the therapeutic effects of three different methods of permethrin treatment for head lice. A parallel, randomized clinical trial was conducted on 157 patients with head lice. The participants underwent eye examination and dry combing by a trained professional. The subjects were randomly divided into three groups and treated with one of the three methods of permethrin application: permethrin shampoo for 10 min, permethrin shampoo for 1 h, or permethrin cream for 10 min on a weekly basis for 3 weeks. Of the 157 participants, 154 completed the study. The group treated with permethrin shampoo for 1 h had the shortest average time for eradication of lice at 1.226 ± 0.422 weeks, which was significantly lower than the other two groups. Additionally, the 1-h permethrin shampoo group had the lowest time for scalp itching of 2.15 ± 0.632 weeks, which was significantly lower than the other two groups. Moreover, the rate of lice eradication in the first week was significantly higher in the 1-h permethrin shampoo group. The results of this study suggest that the use of 1% permethrin shampoo for 1 h is more effective in eradicating head lice within the first week of treatment and in relieving scalp itching during the second week.

Strong insect-resist property and wash-durability exhibited by wool fabric sustainably treated with a natural diterpenoid and a synthetic pyrethroid under subcritical CO2

To conserve wool textiles from insect attack, they are frequently treated with emulsions of natural and synthetic pyrethroid in an aqueous medium. Although the treatment is highly effective, it produces toxic effluent. In this work, insect-resist wool fabrics were produced by treating them with a natural diterpene (totarol), and a synthetic pyrethroid (permethrin) in a subcritical carbon dioxide (subc-CO2) medium. The totarol treatment failed to provide any insect-resist activity but the permethrin treatment even at 0.03% on the weight of wool fiber (owf) showed excellent insect-resist properties and the mortality of the larvae was more than 98%. The wool fabrics treated with permethrin at 0.03% owf under subc-CO2 only marginally lost insect resistance after 20 washes (equivalent to 80 domestic washes) but at 0.09% owf, still, the mortality of larvae was more than 98%. However, the fabric treated with 0.05% owf by the traditional aqueous treatment completely lost its insect-resistance property after 5 washes. The Soxhlet extraction of permethrin with dichloromethane from the treated fabric and GC-MS analysis of the extracted permethrin suggest that most of the permethrin was absorbed into the wool fiber. The developed process could be a durable and sustainable treatment for the conservation of wool textiles.

Intensified Permethrin Treatment of Scabies in Young Children

Intensified Permethrin Treatment of Scabies in Young Children

Can we increase the success of scabies treatment? The effect of removing tunnels from patients in the success of scabies treatment.

Recently, there has been an increase in scabies infestations. Moreover, the number of patients who do not benefit from conventional treatment regimens is increasing rapidly worldwide. This situation leads clinicians to seek new treatments. To evaluate the contribution of mechanical parasite removal to treatment success when applied prior to topical permethrin 5% treatment. The mechanical removal process was applied once during diagnosis. Two groups of 30 people each were included in the study. Permethrin treatment was given directly to the first group without any procedure. In the second group, the maximum number of tunnels that could be detected were removed from patients. After this procedure, the group received permethrin treatment. All patients were called for control after 10 days, and treatment response rates were evaluated. Sixteen (53.3%) patients who received permethrin treatment directly without any procedure responded to the treatment. In the remaining 14 (46.6%) patients, tunnels and Sarcoptes mites were still present. In the second group, which underwent tunnel removal, complete recovery was observed in 26 (86.6%) patients. The patients who did not benefit from the treatment in the study group had relatively less tunnel removal from their bodies. Removing the tunnel from the patient before the treatment increases the success of the treatment. Considering that there are 8-10 parasites on average in scabies patients, it has been determined that the tunnel removal method is not difficult and contributes to therapeutic success.

Integration of Control Strategies to Optimize Management of Ambrosia Beetles (Coleoptera: Curculionidae, Scolytinae) and Phytophthora Root Rot (Peronosporales: Peronosporaceae) in Flowering Dogwoods (Cornalaes: Cornaceae) After Simulated Flooding.

Ambrosia beetles (Coleoptera: Curculionidae, Scolytinae) and Phytophthora root rot (Peronosporales: Peronosporaceae) cause significant damage to the ornamental industry in the United States. In this study, mefenoxam (fungicide), permethrin (insecticide), and charcoal + kaolin were used in different combinations with Phytophthora cinnamomi (Rands: Peronosporales: Peronosporaceae) inoculated and noninoculated plants to optimize the management of ambrosia beetles and Phytophthora root rot. Treatment applications were performed in two trials on 1 (mefenoxam, drench), 18 (P. cinnamomi inoculation), or 19 (permethrin, spray) days before instigating flood stress or 2 d after flood stress (charcoal + kaolin, spray), respectively. Flooding was maintained for 21 d. Ambrosia beetle attacks and plant growth data were recorded. Tree roots were rated at study end for disease severity and root samples were plated on PARPH-V8 medium to determine the percentage of pathogen recovery. In both trials, the combination of mefenoxam + permethrin treatment had reduced disease severity and ambrosia beetle attacks compared to the inoculated controls. Permethrin-treated trees had shorter galleries compared to controls in trial 1 and no gallery formation in trial 2. In both trials, no differences were observed among the treatments in numbers of galleries with eggs and adults, but mefenoxam + charcoal + kaolin had significantly fewer galleries with larvae among the noninoculated trees compared with the respective control in trial 1. Overall, treatments containing combinations of mefenoxam + permethrin had reduced disease severity and ambrosia beetle attacks.

Evaluation of surface versus total permethrin content in permethrin-treated clothing: Implications for protection against mosquitoes

ABSTRACT Permethrin is a synthetic pyrethroid insecticide used to treat uniforms (e.g. military, foresters) and other clothing to protect people against pests (e.g., mosquitoes, ticks). Pests contacting the surface of permethrin-treated clothing (PTC) are repelled and/or killed, depending on the dose and duration of exposure. Hence, it is important to assess the amount of permethrin on the surface of clothing. Fabric swatches prepared using two commercially available permethrin treatments (Insect Shield® & Sawyer Repellant) and one laboratory created treatment (4g permethrin/L) were tested. A Martindale Abrasion and Pilling Tester (MAPT) and gas chromatography were used to assess surface permethrin content (SPC) and total permethrin content (TPC). Sawyer PTC had the highest SPC (mean ± standard error) (32.68±14.55µg/g), followed by Insect Shield® (23.35±2.71µg/g) and lab-created 4g/L permethrin (8.7±0.78µg/g). SPC (after 1000 rubs on MAPT) for Insect Shield®, Sawyer, and 4g/L permethrin groups was significantly lower than TPC (P=0.011, P<0.001, and P=0.001, respectively). The SPC/TPC relationship varied widely between permethrin treatment methods and practical implications for this are discussed. Mosquito repellency tests indicate that Insect Shield®, Sawyer, and lab-created (4g/L) permethrin-treated fabrics showed a significantly higher repellency rate than control (untreated) fabrics (P=0.001, P<0.0001, P<0.0001, respectively). While Insect Shield® had the highest repellency rate against susceptible (53%) and exposed (48%) mosquitoes, differences between groups were not significant. Repellency rates indicate SPC plus other factors (e.g. treatment method) may contribute to mosquito repellency and should be considered in risk assessments for protection against pests.

Scabies increase during the COVID-19 pandemic: should we change our treatment strategy during the pandemic?

Scabies is a highly contagious, parasitic infestation caused by Sarcoptes scabiei var. hominis. There are some reports which claim the incidence of scabies has increased during COVID-19 lockdown. In this study, we aimed to compare the prevalence of scabies between March to September 2020 - the first six months of the COVID-19 outbreak in Turkey - and March to September 2019 - the same period in the previous year. Case number percentages were compared month-over-month and by total numbers for each specified period. Pearson's chi-squared test was the comparison tool used. We checked the records of 36,469 patients who were admitted to Bezmialem Vakif University, Faculty of Medicine, Dermatology Department, a tertiary healthcare center, between March and September 2019, and out of this number, 258 patients had been diagnosed with scabies. The overall scabies case percentage was 0.71% and the range of monthly prevalence was 0.57%-0.83%. During the corresponding period in 2020, 26,219 dermatology patients were admitted, and 465 of those patients were diagnosed with scabies. The overall scabies case percentage was 1.77% and the range of monthly prevalence was 1.37%-3.46%. Scabies prevalence percentages were statistically significantly higher in all months and in the overall total in 2020 (P<0.001). Our nine patients, who admitted in 2020, did not respond to permethrin treatment but responded well to an ivermectin and permethrin combination. Scabies incidence has increased during the COVID-19 pandemic according to our study. We believe there may be an underreported resistance to permethrin and that starting treatment with oral ivermectin in combination with topical permethrin in extraordinary times, such as a pandemic, may help to control outbreaks.

Assessing Durability and Safety of Permethrin Impregnated Uniforms Used by Outdoor Workers to Prevent Tick Bites after One Year of Use.

Long lasting permethrin-impregnated (LLPI) clothing can retain permethrin and repel ticks for up to three months and without exceeding EPA-approved safe levels; however, little is known about longer term effects of wearing LLPI clothing. Here, permethrin content was measured in new forester pants soon after initial impregnation (Insect Shield) and again one year later after being repeatedly worn by foresters in the field. Urine samples were collected from foresters for biomonitoring of permethrin metabolites at multiple time intervals (pre-use, one-month, three-to-four-months, and one-year post-use). Lethality against nymphal Ixodes scapularis Say was measured in clothing after one year of wear by foresters. Furthermore, to test potential variability in permethrin impregnation of different batches of clothing, separate sets of clothing were anonymously sent to Insect Shield for permethrin treatment over a period of three months and permethrin was quantified. Results demonstrated 33% of participants' pants had no measurable permethrin after one year of wear and permethrin content and tick mortality varied significantly between clothing. Only two of the participants' clothing resulted in ≥ 30% tick mortality after one year of wear. Significant differences were observed in 3-PBA and trans-DCCA, but not cis-DCCA metabolites in participants over the four measured time points and were higher than general United States population levels. This study provides practical information on the safety (measured by urinary metabolites) over time of LLPI clothing. It also provides snapshots (pre-washing and after one year of wear) of effectiveness of LLPI clothing as personal protective equipment against ticks for outdoor workers.

Is there a really resistance to scabies treatment with permethrin? In vitro killing activity of permethrin on Sarcoptes scabiei from patients with resistant scabies.

Recently, there have been increased scabies infestations but many patients do not respond to treatment. Clinicians are hesitant to use permethrin despite the fact that treatment failure may be due to noncompliance with the treatment rather than permethrin resistance. We aimed to investigate the permethrin resistance of mites collected from patients who have endured scabies for at least 3months despite permethrin treatment. Parasites in patients who had scabies for at least 3months despite permethrin treatment were collected. Only parasites that were not damaged during sampling, not fragmented and had full motion were included. Parasites were divided into four groups, each with 15 parasites. Immersion oil was dripped on the control group and 5%, 7%, and 10% permethrin was added to the study groups. The responses of the parasites to the applied agents were examined using a digital microscope. All solutions, except the control group, killed the scabies mite. The mean survival time (ST) in the 5%, 7%, and 10% permethrin groups was 360 ± 33.2, 340 ± 31.4, and 320 ± 30.2min, respectively. There was no statistically significant difference in the mean ST in the permethrin groups. The mean ST in the control group was 46 ± 1.5h. The mean ST difference between the control and permethrin-treated groups was significant (p= 0.03). There was no resistance to permethrin, which should maintain its place as first line treatment of scabies. Treatment noncompliance, rather than permethrin resistance, seems to be the underlying factor in the chronicity of scabies.

Club Cells Are the Primary Target for Permethrin-Induced Mouse Lung Tumor Formation.

Permethrin has been shown to increase lung adenomas in female CD-1 mice, but not in male mice or Wistar rats. The proposed mode of action (MOA) for permethrin-induced female mouse lung tumor formation involves morphological changes in Club cells; increased Club cell proliferation; increased Club cell hyperplasia, and lung tumor formation. In this study, the treatment of female CD-1 mice with tumorigenic doses (2500 and 5000 ppm) of permethrin, but not with a nontumorigenic dose (20 ppm), for 14 and/or 28 days increased Club cell replicative DNA synthesis. Global gene expression analysis of female mouse lung samples demonstrated that permethrin treatment up-regulated 3 genes associated with cell proliferation, namely aldehyde dehydrogenase 3a1 (Aldh3a1), oxidative stress-induced growth inhibitor 1, and thioredoxin reductase 1. Treatment with 2500 and 5000 ppm, but not 20 ppm, permethrin for 7 days produced significant increases in mRNA levels of these 3 genes. Immunohistochemical analysis demonstrated that Club cell secretory protein, CYP2F2, and ALDH3A1 colocalized in Club cells; confirmed by flow cytometry analysis of lung cells employing KI67 as a cell proliferation marker. Overall, the present data extend the proposed MOA by demonstrating that Club cells are the primary initial target of permethrin administration in female mouse lungs. As humans are quantitatively much less sensitive to agents that increase Club cell proliferation and lung tumor formation in mice, it is most likely that permethrin could not produce lung tumors in humans. This conclusion is supported by available negative epidemiological data from several studies.

High-fat diet-induced aggravation of cardiovascular impairment in permethrin-treated Wistar rats

This study characterized the impact of post-weaning high-fat diet (HFD) and/or permethrin (PER) treatment on heart dysfunction and fibrosis, as well as atherogenic risk, in rats by investigating interactions between HFD and PER. Our results revealed that HFD and/or PER induced remarkable cardiotoxicity by promoting cardiac injury, biomarker leakage into the plasma and altering heart rate and electrocardiogram pattern, as well as plasma ion levels. HFD and/or PER increased plasma total cholesterol, triacylglycerols, and low-density lipoprotein (LDL) cholesterol levels but significantly reduced high-density lipoprotein (HDL) cholesterol. Cardiac content of peroxidation malonaldehyde, protein carbonyls, and reactive oxygen species were remarkably elevated, while glutathione levels and superoxide dismutase, catalase and glutathione peroxidase activities were inhibited in animals receiving a HFD and/or PER. Furthermore, cardiac DNA fragmentation and upregulation of Bax and caspase-3 gene expression supported the ability of HFD and/or PER to induce apoptosis and inflammation in rat hearts. High cardiac TGF-β1 expression explained the profibrotic effects of PER either with the standard diet or HFD. Masson’s Trichrome staining clearly demonstrated that HFD and PER could cause cardiac fibrosis. Additionally, increased oxidized LDL and the presence of several lipid droplets in arterial tissues highlighted the atherogenic effects of HFD and/or PER in rats. Such PER-induced cardiac and vascular dysfunctions were aggravated by and associated with a HFD, implying that obese individuals may be more vulnerable to PER exposure. Collectively, post-weaning exposure to HFD and/or PER may promote heart failure and fibrosis, demonstrating the pleiotropic effects of exposure to environmental factors early in life.

Effective control of the motile stages of Amblyomma americanum and reduced Ehrlichia spp. prevalence in adults via permethrin treatment of white-tailed deer in coastal Connecticut, USA

The lone star tick, Amblyomma americanum, is a common human-biting species whose range has been largely restricted to the southeastern United States, until recent detections of established populations on Long Island, New York and throughout coastal southern New England. We evaluated the effectiveness of topical treatment of 10 % permethrin delivered via 4-poster devices to white-tailed deer, Odocoileus virginianus, in the management of a newly discovered A. americanum population in Norwalk, Connecticut. Using a high-density deployment of one 4-poster device/12.7 ha, we were successful in significantly reducing densities of host-seeking adults (93 % reduction), nymphs (92 %), and larvae (96 %) from 2018 to 2020. We also documented a significant reduction (87 %) in parasitizing adults and nymphs on white-tailed deer from 2018 to 2019. The prevalence of Ehrlichia chaffeensis and Ehrlichia ewingii combined in host-seeking adults declined significantly from 47 % at the time the A. americanum population was discovered in 2017 to 7% in 2020. However, the prevalence in nymphs remained static (∼9%) throughout the study period. These data demonstrate that, when properly deployed in a density-dependent manner in terms of deer abundance, 4-poster devices can effectively manage parasitizing and host-seeking A. americanum populations and reduce the prevalence of two ehrlichial species of public health importance.

Hepatoprotective Effects of Taraxacum officinale Root Extract on Permethrin-induced Liver Toxicity in Adult Mice

Background: Globally, permethrin is used as an insecticide for pest control in indoor environments and in agriculture to enhance food production by eradicating undesirable insects and controlling disease vectors. &#x0D; Objective: The present study investigated the protective effects of Taraxacum officinale (dandelion) on permethrin-induced liver injury in mice. &#x0D; Methods: Adult mice were divided into four groups. The first group was the negative control group, whereas the second group was the positive control group that received dandelion through the diet at 2% (corresponding to a dose of 5 g/kg bw). The third group received permethrin (96 mg/kg bw) by gavage, whereas the fourth group received permethrin and a diet enriched with dandelion (cotreatment). All mice were sacrificed after 14 days of treatment.&#x0D; Results: Biomarkers of liver toxicity (AST, ALT, ALP, and LDH activities and bilirubin level) increased following permethrin treatment. Permethrin induced oxidative stress, which was indicated by an increase in MDA and GSH levels as well as GPx activity and a decrease in SOD activity. Permethrin treatment caused histological alterations in the liver, whereas co-treatment with dandelion reduced liver injury. Our results revealed that alterations of biochemical parameters and liver histological profile in mice following permethrin exposure were reversed towards normalization by the treatment with dandelion roots extract. &#x0D; Conclusion: The protective effect of this plant might be due to its antioxidant capacity.

Multi- and transgenerational effects following early-life exposure of zebrafish to permethrin and coumarin 47: Impact on growth, fertility, behavior and lipid metabolism

Transgenerational effects induced by environmental stressors are a threat to ecosystems and human health. However, there is still limited observation and understanding of the potential of chemicals to influence life outcomes over several generations. In the present study, we investigated the effects of two environmental contaminants, coumarin 47 and permethrin, on exposed zebrafish (F0) and their progeny (F1–F3). Coumarin 47 is commonly found in personal care products and dyes, whereas permethrin is used as a domestic and agricultural pyrethroid insecticide/insect repellent. Zebrafish (F0) were exposed during early development until 28 days post-fertilization and their progeny (F1–F3) were bred unexposed. On one hand, the effects induced by coumarin 47 suggest no multigenerational toxicity. On the other hand, we found that behavior of zebrafish larvae was significantly affected by exposure to permethrin in F1 to F3 generations with some differences depending on the concentration. This suggests persistent alteration of the neural or neuromuscular function. In addition, lipidomic analyses showed that permethrin treatment was partially correlated with lysophosphatidylcholine levels in zebrafish, an important lipid for neurodevelopment. Overall, these results stress out one of the most widely used pyrethroids can trigger long-term, multi- and possibly transgenerational changes in the nervous system of zebrafish. These neurobehavioral changes echo the effects observed under direct exposure to high concentrations of permethrin and therefore call for more research on mechanisms underlying effect inheritance.

Effectiveness of melatonin to restore fish brain activity in face of permethrin induced toxicity

Present study demonstrates permethrin induced oxidative damage in fish brain and explores effectiveness of melatonin to ameliorate brain function. Adult female Notopterus notopterus were exposed to nominal permethrin concentrations at 1/20th (0.34 μg/l) and 1/10th (0.68 μg/l) of LC50 for 15 days. The measured permethrin concentrations using gas chromatography (GC-ECD) were 0.28 μg/l and 0.57 μg/l, respectively. Some fish were sacrificed to collect brain tissue after 15 days of exposure. Remaining fish from both groups were administered exogenous melatonin (50 μg/kg, 100 μg/kg body weight) for 7 days and brain tissues were collected. Brain enzymes, ntioxidant factors, HSP70, HSP90, nuclear factor-kappa binding (NFkB), melatonin receptor (MT1R) proteins were measured. Permethrin treatment significantly (P < 0.05) decreased the levels of glutathione and brain enzymes. Malondialdehyde (MDA), xanthine oxidase (XO), HSPs increased at each concentration of permethrin. However, superoxide dismutase, glutathione s-transferase levels increased at low permethrin concentration followed by sharp decrease at higher concentration. Expression of NFkB and MT1R increased significantly (P < 0.05). Melatonin administration reinstated activity of brain enzymes, reduced MDA, XO levels and modulated HSPs. Melatonin also increased expression of NFkB and MT1R. Exogenous melatonin improves oxidative status in permethrin stressed fish brain. Melatonin modulates expression of HSPs that enables brain to become stress tolerant and survive by initiating NFkB translocation. Melatonin could act through melatonin receptor protein to induce synthesis of antioxidant proteins. Therefore the study successfully evaluates the potential of melatonin application for better culture and management of fish against pesticide toxicity.