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Niklas B, Rydzewski J, Lapied B, Nowak W. Toward Overcoming Pyrethroid Resistance in Mosquito Control: The Role of Sodium Channel Blocker Insecticides. Int J Mol Sci 2023; 24:10334. [PMID: 37373481 DOI: 10.3390/ijms241210334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 06/14/2023] [Accepted: 06/16/2023] [Indexed: 06/29/2023] Open
Abstract
Diseases spread by mosquitoes lead to the death of 700,000 people each year. The main way to reduce transmission is vector control by biting prevention with chemicals. However, the most commonly used insecticides lose efficacy due to the growing resistance. Voltage-gated sodium channels (VGSCs), membrane proteins responsible for the depolarizing phase of an action potential, are targeted by a broad range of neurotoxins, including pyrethroids and sodium channel blocker insecticides (SCBIs). Reduced sensitivity of the target protein due to the point mutations threatened malaria control with pyrethroids. Although SCBIs-indoxacarb (a pre-insecticide bioactivated to DCJW in insects) and metaflumizone-are used in agriculture only, they emerge as promising candidates in mosquito control. Therefore, a thorough understanding of molecular mechanisms of SCBIs action is urgently needed to break the resistance and stop disease transmission. In this study, by performing an extensive combination of equilibrium and enhanced sampling molecular dynamics simulations (3.2 μs in total), we found the DIII-DIV fenestration to be the most probable entry route of DCJW to the central cavity of mosquito VGSC. Our study revealed that F1852 is crucial in limiting SCBI access to their binding site. Our results explain the role of the F1852T mutation found in resistant insects and the increased toxicity of DCJW compared to its bulkier parent compound, indoxacarb. We also delineated residues that contribute to both SCBIs and non-ester pyrethroid etofenprox binding and thus could be involved in the target site cross-resistance.
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Affiliation(s)
- Beata Niklas
- Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University, Grudziadzka 5, 87-100 Torun, Poland
| | - Jakub Rydzewski
- Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University, Grudziadzka 5, 87-100 Torun, Poland
| | - Bruno Lapied
- University Angers, INRAE, SIFCIR, SFR QUASAV, F-49045 Angers, France
| | - Wieslaw Nowak
- Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University, Grudziadzka 5, 87-100 Torun, Poland
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2
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Wu YJ, Wang BJ, Wang MR, Peng YC, Cao HQ, Sheng CW. Control efficacy and joint toxicity of metaflumizone mixed with chlorantraniliprole or indoxacarb against the fall armyworm, Spodoptera frugiperda. PEST MANAGEMENT SCIENCE 2023; 79:1094-1101. [PMID: 36334007 DOI: 10.1002/ps.7278] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Revised: 11/02/2022] [Accepted: 11/03/2022] [Indexed: 06/16/2023]
Abstract
BACKGROUND The fall armyworm (FAW), Spodoptera frugiperda is the main destructive pest of grain crops, and has led to substantial economic losses worldwide. Chemical pesticides are the most effective way to manage FAW. Here, a laboratory test using an artificial diet-incorporated assay was conducted to determine the toxicity of five insecticides and the joint effect of the binary combination insecticides to FAW larvae. A field plot test using foliar spray was carried out to assess the control efficacy of metaflumizone mixed with chlorantraniliprole or indoxacarb against FAW. RESULTS The bioassay results showed that metaflumizone had a stronger insecticidal effect than indoxacarb toward FAW larvae. Furthermore, the mixture of metaflumizone and chlorantraniliprole in a volume ratio of 3:7 had the strongest synergistic effect against FAW, with a co-toxicity coefficient (CTC) of 317.18. The best synergistic effect for mixtures of metaflumizone and indoxacarb was observed at a 1:9 volume ratio, with a CTC of 185.98. However, there was an antagonistic effect of metaflumizone mixed with emamectin benzoate and with lufenuron, because the co-toxic factor was less than -20 at volume ratios of 8:2 and 9:1, respectively. According to the results of the field trial, metaflumizone mixed with chlorantraniliprole or indoxacarb at a 50% reduction of the application rate can effectively control FAW with efficacy ranging from 77.73% to 94.65% 1-7 days postapplication. CONCLUSION Overall, our findings suggest that metaflumizone and its binary combination insecticides can be utilized in FAW integrated pest management programs. © 2022 Society of Chemical Industry.
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Affiliation(s)
- Yu-Jie Wu
- Anhui Province Key Laboratory of Integrated Pest Management on Crops, School of Plant Protection, Anhui Agricultural University, Hefei, P.R. China
| | - Bing-Jie Wang
- Anhui Province Key Laboratory of Integrated Pest Management on Crops, School of Plant Protection, Anhui Agricultural University, Hefei, P.R. China
| | - Meng-Ru Wang
- Anhui Province Key Laboratory of Integrated Pest Management on Crops, School of Plant Protection, Anhui Agricultural University, Hefei, P.R. China
| | - Ying-Chuan Peng
- Institute of Entomology, Jiangxi Agricultural University, Nanchang, P.R. China
| | - Hai-Qun Cao
- Anhui Province Key Laboratory of Integrated Pest Management on Crops, School of Plant Protection, Anhui Agricultural University, Hefei, P.R. China
- Anhui Province Engineering Laboratory for Green Pesticide Development and Application, School of Plant Protection, Anhui Agricultural University, Hefei, P.R. China
| | - Cheng-Wang Sheng
- Anhui Province Key Laboratory of Integrated Pest Management on Crops, School of Plant Protection, Anhui Agricultural University, Hefei, P.R. China
- Anhui Province Engineering Laboratory for Green Pesticide Development and Application, School of Plant Protection, Anhui Agricultural University, Hefei, P.R. China
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Moreira LB, Lima LLR, de Sá Farias E, Carvalho GA. Response of Doru luteipes (Dermaptera: Forficulidae) to insecticides used in maize crop as a function of its life stage and exposure route. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:15010-15019. [PMID: 36168013 DOI: 10.1007/s11356-022-23196-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2022] [Accepted: 09/19/2022] [Indexed: 06/16/2023]
Abstract
The present study aimed to evaluate insecticide toxicity to Doru luteipes (Scudder), a major predator of maize pests. Lethal and sublethal effects were assessed on nymphs and adults exposed to the insecticides through contact (maize leaves) and ingestion (prey eggs) routes. Tested insecticides included a biopesticide (Spodoptera frugiperda multiple nucleopolyhedrovirus, SfMNPV), modern (flubendiamide and metaflumizone), and older neurotoxins (imidacloprid + β-cyfluthrin). The imidacloprid/β-cyfluthrin mix was highly toxic (100% mortality) to the predator, regardless of the exposure route and predator stage. Metaflumizone caused mortality higher than 95% and 45% of nymphs and adults. Flubendiamide and SfMNPV were the least toxic insecticides, not differing from the untreated control in any of the assessed endpoints. Adult tibial length did not differ among treatments. Metaflumizone impaired egg consumption by nymphs and walking distance of adult D. luteipes. Overall, the insecticides caused a more pronounced effect on D. luteipes nymphs than on adults and were more toxic by the contact route. From these findings, flubendiamide and SfMNPV are safer for D. luteipes and should head insecticide choice in integrated pest management programs in maize.
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Affiliation(s)
- Luciano Bastos Moreira
- Department of Entomology, Universidade Federal de Lavras, PB 3037, Lavras, Minas Gerais, 37200-900, Brazil
| | | | - Elizeu de Sá Farias
- Department of Entomology, Universidade Federal de Lavras, PB 3037, Lavras, Minas Gerais, 37200-900, Brazil
| | - Geraldo Andrade Carvalho
- Department of Entomology, Universidade Federal de Lavras, PB 3037, Lavras, Minas Gerais, 37200-900, Brazil.
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4
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Synthesis of Emodin Acylhydrazone Derivatives and Determination of Vibrio harveyi Inhibitory Activity. Chem Nat Compd 2022. [DOI: 10.1007/s10600-022-03645-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Rezende-Teixeira P, Dusi RG, Jimenez PC, Espindola LS, Costa-Lotufo LV. What can we learn from commercial insecticides? Efficacy, toxicity, environmental impacts, and future developments. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 300:118983. [PMID: 35151812 DOI: 10.1016/j.envpol.2022.118983] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 01/26/2022] [Accepted: 02/08/2022] [Indexed: 05/27/2023]
Abstract
Worldwide pesticide usage was estimated in up to 3.5 million tons in 2020. The number of approved products varies among different countries, however, in Brazil, there are nearly 5000 of such products available. Among them, insecticides correspond to a group of mounting importance for controlling crop pests and disease-associated vectors in public health. Unfortunately, resistance to commercially approved insecticides is commonly observed, limiting the use of these products. Thus, the search for more effective and environmentally friendly products is both a challenge and a necessity since several insecticides are no longer allowed in many countries. In this review, we discuss the historical strategies used in the development of modern insecticides, including chemical structure alterations, mechanism of action and their impact on insecticidal activity. The environmental impact of each pesticide class is also discussed, with persistence data and activity on non-target organisms, along with the human toxicological effect. By tracing the historical route of discovery and development of blockbuster pesticides like DDT, pyrethroids and organophosphates, we also aim to categorize and relate the successful chemical alterations and novel pesticide development strategies that resulted in safer alternatives. A brief discussion on the Brazilian registration procedure and a perspective of insecticides currently approved in the country was also included.
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Affiliation(s)
- Paula Rezende-Teixeira
- Laboratório de Farmacologia Marinha, Departamento de Farmacologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, 05508-900, São Paulo, SP, Brazil
| | - Renata G Dusi
- Laboratório de Farmacognosia, Universidade de Brasília, Campus Universitário Darcy Ribeiro, Brasília, 70910-900, Brazil
| | - Paula C Jimenez
- Laboratório de Bioprospecção de Organismos Marinhos, Instituto do Mar, Universidade Federal de São Paulo, Santos, SP, Brazil
| | - Laila S Espindola
- Laboratório de Farmacognosia, Universidade de Brasília, Campus Universitário Darcy Ribeiro, Brasília, 70910-900, Brazil
| | - Letícia V Costa-Lotufo
- Laboratório de Farmacologia Marinha, Departamento de Farmacologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, 05508-900, São Paulo, SP, Brazil.
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6
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Qiao Z, Fu W, Zhang Y, Chen R, Xu Z, Li Z, Shao X. Azobenzene-Semicarbazone Enables Optical Control of Insect Sodium Channels and Behavior. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2021; 69:15554-15561. [PMID: 34905925 DOI: 10.1021/acs.jafc.1c06404] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Photopharmacology uses molecular photoswitches to establish control over the action of bioactive molecules. The application of photopharmacology in the research of invertebrate sodium channels has not been investigated. Here we report several photochromic ligands of metaflumizone. One ligand, termed ABM04, underwent reversible trans-cis isomerization under ultraviolet or blue light irradiation. cis-ABM04 had excellent larvicidal activity against mosquito larvae with an LC50 value of 4.39 μM and showed insecticidal activity against Mythimna separata with an LC50 value of 7.19 μM. However, trans-ABM04 was not found to have biological activity. ABM04 (10 μM) can induce depolarization of dorsal unpaired median neurons and enable the real-time photoregulation of mosquito larval behavior. The precise regulation of invertebrate sodium channels is realized for the first time, which provides a new strategy for the basic and accurate research of invertebrate sodium channels.
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Affiliation(s)
- Zhi Qiao
- Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, P. R. China
| | - Wen Fu
- Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, P. R. China
| | - Yongchao Zhang
- Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, P. R. China
| | - Ruijia Chen
- Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, P. R. China
| | - Zhiping Xu
- Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, P. R. China
| | - Zhong Li
- Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, P. R. China
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Xusheng Shao
- Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, P. R. China
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China
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Barbosa MG, Souza SA, André TPP, Pontes ADS, Teixeira CS, Pereira FF, Pastori PL. Do fall armyworm's Metaflumizone resistante populations affect the activity of Trichogramma pretiosum? BRAZ J BIOL 2021; 83:e245273. [PMID: 34669790 DOI: 10.1590/1519-6984.245273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Accepted: 06/07/2021] [Indexed: 11/22/2022] Open
Abstract
The possible interference of resistant pest's populations to insecticides in natural enemies in the action thas not been clarified yet. Thus, this study aimed to evaluate Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) performance on Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) eggs with resistance frequency to the Metaflumizone over six generations of product exposure. Egg cards (2.0 x 7.0 cm) containing eggs from two populations of S. frugiperda, (resistant to Metaflumizone and the other susceptible), were exposed to T. pretiosum females for 24 hours in free-choice and no-choice testing in three generations (G1, G4, and G6). A completely randomized experimental design was used with 25 replications, each consisting of an egg card (experimental unit) containing 20 eggs. The parameters evaluated were: parasitism (%), emergence (%), sex ratio, number of emerged parasitoids per egg and males/females longevity. ANOVA and Tukey test (P≤ 0.05) were applied on the results. Results showed a reduction in parasitism [41.0% (G1) and 28.4% (G4)], egg emergence (17.5%) and parasitoids/egg [16.2 (G4) and 17.2 (G6)] in eggs originating from the population with resistance frequency. Females emerging from G6 populations eggs without exposure to Metaflumizone had greater longevity (3.5 days more) than the resistant population. The sex ratio and male longevity were not affected. The results indicate a reduction in T. pretiosum activity if S. frugiperda populations have some frequency of resistance to Metaflumizone.
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Affiliation(s)
- M G Barbosa
- IN Soluções Biológicas LTDA, Fortaleza, CE, Brasil
| | - S A Souza
- Universidade de São Paulo - UNESP, Faculdade de Ciências Agronômicas, Departamento de Proteção de Plantas, Botucatu, SP, Brasil
| | - T P P André
- Universidade Federal do Ceará - UFC, Departamento de Fitotecnia, Laboratório de Entomologia Aplicada, Fortaleza, CE, Brasil
| | - A D S Pontes
- Universidade Federal do Ceará - UFC, Departamento de Fitotecnia, Laboratório de Entomologia Aplicada, Fortaleza, CE, Brasil
| | - C S Teixeira
- Universidade Federal do Ceará - UFC, Departamento de Fitotecnia, Laboratório de Entomologia Aplicada, Fortaleza, CE, Brasil
| | - F F Pereira
- Universidade Federal da Grande Dourados - UFGD, Faculdade de Ciências Biológicas e Ambientais, Dourados, MS, Brasil
| | - P L Pastori
- Universidade Federal do Ceará - UFC, Departamento de Fitotecnia, Laboratório de Entomologia Aplicada, Fortaleza, CE, Brasil
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8
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Bi Y, Yao W, Han L, Qiao C, Song S, Qin F, Dong Q, Hao X, Xu Y. Method validation and residue analysis of methoxyfenozide and metaflumizone in Chinese broccoli under field conditions by liquid chromatography with tandem mass spectrometry. J Sep Sci 2021; 44:3860-3869. [PMID: 34384003 DOI: 10.1002/jssc.202100348] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 07/30/2021] [Accepted: 08/05/2021] [Indexed: 11/06/2022]
Abstract
Methoxyfenozide and metaflumizone are insecticides used on Chinese broccoli to prevent insects and increase yield. However, the residues are potentially harmful to the environment and consumers. In this study, the quick, easy, cheap, effective, rugged, safe method with high-performance liquid chromatography with tandem mass spectrometry was modified and validated for determination of methoxyfenozide and metaflumizone in Chinese broccoli. The clean-up efficiency of different sorbents including C18 , primary secondary amine, graphitized carbon black, and carbon nanofiber was compared. Recoveries of the validated method were 71.8-94.6% with relative standard deviations of 1.5-3.2% and the limits of quantification were 0.01 and 0.005 mg/kg for methoxyfenozide and metaflumizone, respectively. A storage stability test showed almost no degradation of methoxyfenozide in Chinese broccoli, however, the degradation rate of metaflumizone was 22.9% after 10-wk storage at -20°C. In field trials in four producing regions, the dissipation of both methoxyfenozide and metaflumizone in Chinese broccoli was fast, with half-lives of only 1.0-5.1 and 0.7-2.5 days, respectively. Terminal residues after application of the two pesticides were all below 1.0 mg/kg after 5 days.
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Affiliation(s)
- Yingying Bi
- College of Science, China Agricultural University, Beijing, P. R. China
| | - Wei Yao
- College of Science, China Agricultural University, Beijing, P. R. China.,Basic Courses Department, Beijing Vocational College of Agriculture, Beijing, P. R. China
| | - Lijun Han
- College of Science, China Agricultural University, Beijing, P. R. China
| | - Chengkui Qiao
- Zhengzhou Fruit Research Institute, Chinese Academy of Agricultural Sciences, Zhengzhou, P. R. China
| | - Shuangyu Song
- College of Science, China Agricultural University, Beijing, P. R. China
| | - Fayi Qin
- College of Science, China Agricultural University, Beijing, P. R. China
| | - Qin Dong
- College of Science, China Agricultural University, Beijing, P. R. China
| | - Xianghong Hao
- College of Science, China Agricultural University, Beijing, P. R. China
| | - Yanjun Xu
- College of Science, China Agricultural University, Beijing, P. R. China
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Barbosa MG, André TPP, Pontes ADS, Souza SA, Oliveira NRX, Pastori PL. Insecticide Rotation and Adaptive Fitness Cost Underlying Insecticide Resistance Management for Spodoptera frugiperda (Lepidoptera: Noctuidae). NEOTROPICAL ENTOMOLOGY 2020; 49:882-892. [PMID: 32632568 DOI: 10.1007/s13744-020-00800-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Accepted: 06/23/2020] [Indexed: 06/11/2023]
Abstract
Rotation of insecticide modes of action is recommended to delay selection for insecticide resistance. In this study, larvae of Spodoptera frugiperda (J.E. Smith) were exposed alternately to spinetoram and metaflumizone with insecticidal and biological response determined. Five generations (G) were evaluated with at least 200 larvae assayed per treatment. The experiment consisted of rearing field-collected and untreated larvae (M-Control), larvae with successive applications of either metaflumizone (M-MET) or spinetoram (M-SPI), and alternation of these insecticides (M-Rotation treatment) consisting of the following treatments: G2 = exposure to SPI, G3 = exposure to MET, G4 = exposure to SPI, G5 = exposure to MET, and G6 = exposure to SPI. Four days after application, those surviving larvae were used to compose the following generations. In the G7, evaluations were made on the selected populations M-MET, M-SPI, M-Rotation, and control larvae to determine biological characteristics used to calculate the fertility life table parameters and further comparisons across treatments. The frequency of resistance was increased at rate of 49.5% and 29.2% after five generations of selection pressure with MET and SPI, respectively. However, rotation of insecticides reduced the frequency of resistance about 50% over the generations. Individuals originated from successive exposures to the insecticides exhibited delayed egg incubation, greater percentage of pupae with deformation, longer larval and pupal periods, and reduction in emergence rate and longevity of adults, suggesting adaptive costs associated with resistance.
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Affiliation(s)
- M G Barbosa
- IN Soluções Biológicas LTDA, Fortaleza, Ceará, Brasil
- Univ. Federal do Ceará, Av. Mister Hull, 2.977, Campus do Pici, Fortaleza, Ceará, CEP 60356-001, Brasil
| | - T P P André
- Univ. Federal do Ceará, Av. Mister Hull, 2.977, Campus do Pici, Fortaleza, Ceará, CEP 60356-001, Brasil
| | - A D S Pontes
- Univ. Federal do Ceará, Av. Mister Hull, 2.977, Campus do Pici, Fortaleza, Ceará, CEP 60356-001, Brasil
| | - S A Souza
- Faculdade de Ciências Agronômicas, Univ. Estadual Paulista "Júlio de Mesquita Filho", Botucatu, São Paulo, Brasil
| | - N R X Oliveira
- Univ. Federal do Ceará, Av. Mister Hull, 2.977, Campus do Pici, Fortaleza, Ceará, CEP 60356-001, Brasil
| | - P L Pastori
- Univ. Federal do Ceará, Av. Mister Hull, 2.977, Campus do Pici, Fortaleza, Ceará, CEP 60356-001, Brasil.
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Shen J, Li Z, Li D, Wang R, Zhang S, You H, Li J. Biochemical Mechanisms, Cross-resistance and Stability of Resistance to Metaflumizone in Plutella xylostella. INSECTS 2020; 11:E311. [PMID: 32429053 PMCID: PMC7291261 DOI: 10.3390/insects11050311] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 05/09/2020] [Accepted: 05/13/2020] [Indexed: 11/17/2022]
Abstract
The diamondback moth, Plutella xylostella (L.) is an important pest of cruciferous crops worldwide. It has developed resistance to many conventional and novel insecticide classes. Metaflumizone belongs to the new chemical class of semicarbazone insecticides. To delay the development of metaflumizone resistance in P. xylostella and to guide insecticide use in the field, the biochemical mechanisms, cross-resistance spectrum, and stability of resistance to metaflumizone were studied in a laboratory-selected resistant strain (metaflu-SEL). Synergism tests with the carboxylesterase inhibitor triphenyl phosphate (TPP), the glutathione S-transferase depletor diethyl maleate (DEM), and the P450 inhibitor piperonyl butoxide(PBO) had no obvious effect on metaflumizone in the metaflu-SEL strain and the susceptible strain (SS) of P. xylostella, with synergism ratios that ranged from 1.02 to 1.86. Biochemical studies revealed that the cytochrome P450-dependent monooxygenase increased only 1.13-fold in the metaflu-SEL strain compared with the UNSEL stain; meanwhile, carboxylesterase and glutathione S-transferase activity showed no difference. These results suggest that these detoxification enzymes may be not actively involved in metaflumizone resistance. Furthermore, the metaflu-SEL population showed a moderate level of cross-resistance to indoxacarb (11.63-fold), but only very low cross-resistance to spinosad (1.75-fold), spinetoram (3.52-fold), abamectin (2.81-fold), beta-cypermethrin (0.71-fold), diafenthiuron (0.79-fold), chlorantraniliprole (2.16-fold), BT (WG-001) (3.34-fold), chlorfenapyr (0.49-fold), and chlorfluazuron (0.97-fold). Moreover, metaflumizone resistance decreased from 1087.85- to 1.23-fold in the metaflu-SEL strain after 12 generations without exposure to metaflumizone. These results are useful for formulating insecticide resistance management strategies to control P. xylostella and to delay the development of metaflumizone resistance in the field.
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Affiliation(s)
- Jun Shen
- College of Horticulture, Xinyang Agriculture and Forestry University, Xinyang 464000, China;
| | - Zhao Li
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China; (Z.L.); (D.L.); (R.W.); (S.Z.); (H.Y.)
| | - Dongyang Li
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China; (Z.L.); (D.L.); (R.W.); (S.Z.); (H.Y.)
| | - Rumeng Wang
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China; (Z.L.); (D.L.); (R.W.); (S.Z.); (H.Y.)
| | - Shuzhen Zhang
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China; (Z.L.); (D.L.); (R.W.); (S.Z.); (H.Y.)
| | - Hong You
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China; (Z.L.); (D.L.); (R.W.); (S.Z.); (H.Y.)
| | - Jianhong Li
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China; (Z.L.); (D.L.); (R.W.); (S.Z.); (H.Y.)
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Sun XX, Li HY, Jiang YJ, Zhang JX, Gu HL, Gao B, Ma JJ, Wang F, Zhou JC, Tian XR, Su J, Wang K. Resistance Risk Evaluated by Metaflumizone Selection and the Effects on Toxicities Over Other Insecticides in Spodoptera exigua (Lepidoptera: Noctuidae). JOURNAL OF ECONOMIC ENTOMOLOGY 2019; 112:2354-2361. [PMID: 31219572 DOI: 10.1093/jee/toz171] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Indexed: 06/09/2023]
Abstract
Metaflumizone is a novel semicarbazone insecticide. It functions as a sodium channel blocker insecticide (SCBI) with excellent insecticidal activity on most economically important lepidopterous pests. This study assessed the resistance risk of Spodoptera exigua (Hübner) (Lepidoptera: Noctuidae) to metaflumizone in the laboratory and the effects of metaflumizone selection on toxicities to other insecticides. Spodoptera exigua collected from a field population at Huizhou in 2012 were successively challenged by metaflumizone to evaluate the risk of resistance evolution. Twelve generations of selection increased resistance to metaflumizone by 3.4-fold and threshold trait analysis revealed that the realized heritability (h2) of this resistance was 0.086. When h2 was equal to 0.086 and 90% of individuals were killed at each generation, LC50 to metaflumizone increased by 10-fold after 15 generations. The selection by metaflumizone did not increase the resistance to indoxacarb, chlorantraniliprole, spinosad, methomyl, or endosulfan, suggesting a lack of cross-resistance. However, metaflumizone challenge upheld the recession of resistance to emamectin benzoate, chlorfluazuron, and tebufenozide. The block of resistance drops by metaflumizone exposure implied a possible cross-resistance between metaflumizone and these three insecticides. These results contribute to integrated resistance management of S. exigua.
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Affiliation(s)
- Xing-Xing Sun
- Jiangsu Coastal Area Institute of Agricultural Science, Yancheng, China
- Institute of Modern Agriculture, Jiangsu Provincial Reclamation and Development Corporation, Nanjing, China
| | - Hong-Yang Li
- Jiangsu Coastal Area Institute of Agricultural Science, Yancheng, China
| | - Ying-Jie Jiang
- Jiangsu Coastal Area Institute of Agricultural Science, Yancheng, China
| | - Jun-Xi Zhang
- Jiangsu Coastal Area Institute of Agricultural Science, Yancheng, China
| | - Hui-Ling Gu
- Jiangsu Coastal Area Institute of Agricultural Science, Yancheng, China
| | - Bo Gao
- Jiangsu Coastal Area Institute of Agricultural Science, Yancheng, China
| | - Jing-Jing Ma
- Jiangsu Coastal Area Institute of Agricultural Science, Yancheng, China
| | - Fan Wang
- Jiangsu Coastal Area Institute of Agricultural Science, Yancheng, China
| | - Jia-Chun Zhou
- Jiangsu Coastal Area Institute of Agricultural Science, Yancheng, China
| | - Xiang-Rui Tian
- Institute of Modern Agriculture, Jiangsu Provincial Reclamation and Development Corporation, Nanjing, China
- College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Jianya Su
- College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Kai Wang
- Jiangsu Coastal Area Institute of Agricultural Science, Yancheng, China
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Liu Y, Di Y, Di Y, Qiao C, Chen F, Yuan F, Yue K, Zhou C. The studies of structure, thermodynamic properties and theoretical analyses of 2-[(4-nitro-benzoyl)-hydrazone]-propionic acid. J Mol Struct 2019. [DOI: 10.1016/j.molstruc.2019.02.050] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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13
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Gosselin-Badaroudine P, Charnet P, Collet C, Chahine M. Metaflumizone inhibits the honeybee Na V 1 channel by targeting recovery from slow inactivation. FEBS Lett 2017; 591:3842-3849. [PMID: 29105054 DOI: 10.1002/1873-3468.12897] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2017] [Revised: 10/25/2017] [Accepted: 10/26/2017] [Indexed: 11/07/2022]
Abstract
Metaflumizone is the latest addition to the armamentarium of the Na+ channel inhibitor insecticide family. We used the Xenopus oocyte expression system and a Markovian model to assess the effect of metaflumizone on Apis mellifera Na+ channels (AmNaV 1). Our results reveal that metaflumizone inhibits AmNaV 1 channels by targeting the kinetics of recovery from slow inactivation. Multistate modeling of fast and slow inactivation of the AmNaV 1 channel made it possible to study the effects of metaflumizone on a set of rate constants underlying the transition between the open and inactivated conformations and provided insights into their specificity. We conclude that the methods we used could be extended to assessing the toxicity of other Na+ channel inhibitor insecticides.
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Affiliation(s)
| | - Pierre Charnet
- CNRS, UMR 5247, Institut des Biomolécules Max Mousseron (IBMM), Université Montpellier 2, France
| | - Claude Collet
- INRA, UR 406 Abeilles et Environnement, Toxicologie Environnementale, Avignon, France
| | - Mohamed Chahine
- Centre de recherche CERVO, Institut universitaire en santé mentale de Québec, QC, Canada.,Department of Medicine, Université Laval, Quebec City, QC, Canada
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Zhang S, Zhang X, Shen J, Li D, Wan H, You H, Li J. Cross-resistance and biochemical mechanisms of resistance to indoxacarb in the diamondback moth, Plutella xylostella. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2017; 140:85-89. [PMID: 28755699 DOI: 10.1016/j.pestbp.2017.06.011] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Revised: 06/10/2017] [Accepted: 06/19/2017] [Indexed: 06/07/2023]
Abstract
Indoxacarb belongs to a class of insecticides known as oxadiazines and is the first commercialized pyrazoline-type voltage-dependent sodium channel blocker. A moderate level of resistance to indoxacarb has evolved in field populations of Plutella xylostella from Central China. In the present study, cross-resistance, resistance stability and metabolic mechanisms of indoxacarb resistance were investigated in this moth species. A P. xylostella strain with a high level of resistance to indoxacarb was obtained through continuous selection in the laboratory. The strain showed cross-resistance to metaflumizone, beta-cypermethrin and chlorfenapyr, but no resistance to cyantraniliprole, chlorantraniliprole, abamectin, chlorfluazuron, spinosad and diafenthiuron compared with the susceptible strain. Synergism tests revealed that piperonyl butoxide (PBO) (synergistic ratio, SR=7.8) and diethyl maleate (DEF) (SR=3.5) had considerable synergistic effects on indoxacarb toxicity in the resistant strain (F58). Enzyme activity data showed there was an approximate 5.8-fold different in glutathione S-transferase (GST) and a 6.8-fold different in cytochrome P450 monooxygenase between the resistant strain (F58) and susceptible strain, suggesting that the increased activity of these two enzymes is likely the main detoxification mechanism responsible for the species' resistance to indoxacarb. These results will be helpful for insecticide resistance management strategies to delay the development of indoxacarb resistance in fields.
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Affiliation(s)
- Shuzhen Zhang
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Xiaolei Zhang
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Jun Shen
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Dongyang Li
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Hu Wan
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Hong You
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, PR China.
| | - Jianhong Li
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, PR China.
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Silver K, Dong K, Zhorov BS. Molecular Mechanism of Action and Selectivity of Sodium Ch annel Blocker Insecticides. Curr Med Chem 2017; 24:2912-2924. [PMID: 27993108 PMCID: PMC5730267 DOI: 10.2174/0929867323666161216143844] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Revised: 11/22/2016] [Accepted: 11/30/2016] [Indexed: 12/19/2022]
Abstract
Sodium channel blocker insecticides (SCBIs) are a relatively new class of insecticides that are represented by two commercially registered compounds, indoxacarb and metaflumizone. SCBIs, like pyrethroids and DDT, target voltage-gated sodium channels (VGSCs) to intoxicate insects. In contrast to pyrethroids, however, SCBIs inhibit VGSCs at a distinct receptor site that overlaps those of therapeutic inhibitors of sodium channels, such as local anesthetics, anticonvulsants and antiarrhythmics. This review will recount the development of the SCBI insecticide class from its roots as chitin synthesis inhibitors, discuss the symptoms of poisoning and evidence supporting inhibition of VGSCs as their mechanism of action, describe the current model for SCBI-induced inhibition of VGSCs, present a model for the receptor for SCBIs on VGSCs, and highlight differences between data collected from mammalian and insect experimental models.
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Affiliation(s)
- Kristopher Silver
- Department of Entomology, Kansas State University, Manhattan, KS 66506, USA
| | - Ke Dong
- Department of Entomology, Genetics and Neuroscience Programs, Michigan State University, East Lansing, MI 48824, USA
| | - Boris S. Zhorov
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada; Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, St. Petersburg, Russia
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Fernández MDM, Medina P, Fereres A, Smagghe G, Viñuela E. Are Mummies and Adults of Eretmocerus mundus (Hymenoptera: Aphelinidae) Compatible With Modern Insecticides? JOURNAL OF ECONOMIC ENTOMOLOGY 2015; 108:2268-2277. [PMID: 26453715 DOI: 10.1093/jee/tov181] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2015] [Accepted: 06/10/2015] [Indexed: 06/05/2023]
Abstract
The parasitic wasp Eretmocerus mundus (Mercet) is an important natural enemy of the widespread key pest Bemisia tabaci (Gennadius). The toxicity of 11 modern insecticides applied at their maximum field recommended rate in Spain was tested in two life stages of E. mundus: adults and mummies. Laboratory and persistence tests were conducted and effects assessed not only in terms of mortality but on reproductive performance as well. Some insecticides caused the same effect to both life stages: flubendiamide, methoxyfenozide, spiromesifen, and flonicamid were harmless, while spinosad and sulfoxaflor were harmful. The last two insecticides cannot be used jointly with E. mundus under any condition because they were highly persistent. The rest of tested insecticides (spirotetramat, metaflumizone, deltamethrin, abamectin, and emamectin) caused some direct mortality to one or both life stages and/or affected reproduction of the parasitic wasp and their harmful effect in the field ranged from short lived (metaflumizone and spirotetramat) to slightly persistent (emamectin) and to moderately persistent (abamectin and deltamethrin). Therefore, they could be recommended for use in integrated pest management programs together with the natural enemy if appropriate safety intervals after insecticide application are observed.
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Affiliation(s)
- María Del Mar Fernández
- Crop Protection Unit, School of Agricultural Sciences, Technical University of Madrid (UPM), Ciudad Universitaria s/n, 28040 Madrid, Spain
| | - Pilar Medina
- Crop Protection Unit, School of Agricultural Sciences, Technical University of Madrid (UPM), Ciudad Universitaria s/n, 28040 Madrid, Spain. Associated Unit IVAS, CSIC-UPM
| | - Alberto Fereres
- Associated Unit IVAS, CSIC-UPM. Institute of Agricultural Sciences, CSIC, Serrano 115 Dpdo, 28006 Madrid, Spain
| | - Guy Smagghe
- Department of Crop Protection, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Ghent, Belgium
| | - Elisa Viñuela
- Crop Protection Unit, School of Agricultural Sciences, Technical University of Madrid (UPM), Ciudad Universitaria s/n, 28040 Madrid, Spain. Associated Unit IVAS, CSIC-UPM.
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Mahmoodi NO, Namroudi M, Ghanbari Pirbasti F, Roohi H, Nikokar I. Practical one-pot synthesis of semicarbazone derivatives via semicarbazide, and evaluation of their antibacterial activity. RESEARCH ON CHEMICAL INTERMEDIATES 2015. [DOI: 10.1007/s11164-015-2235-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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18
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Tian X, Sun X, Su J. Biochemical mechanisms for metaflumizone resistance in beet armyworm, Spodoptera exigua. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2014; 113:8-14. [PMID: 25052521 DOI: 10.1016/j.pestbp.2014.06.010] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2014] [Revised: 06/22/2014] [Accepted: 06/23/2014] [Indexed: 06/03/2023]
Abstract
The metaflumizone, which belongs to the class of voltage-dependent sodium channel blockers, was registered to control Spodoptera exigua on vegetables in China in 2009. The present study revealed S. exigua has developed high resistance to this novel chemistry insecticide shortly after 2-3 years application in Guangdong Province of China. The metabolic mechanisms for metaflumizone resistance in this insect were analysed. The inhibitor of esterases greatly potentiates the toxicity of this chemical against the field resistant populations. The synergism ratio is 5.7 and 3.4-fold for S. exigua collected from Huizhou, Guangdong Province in 2011 and 2012, respectively. The activity of esterases in field populations (HZ12) is also significantly greater than that in the susceptible strain, and further significantly increased by challenge with metaflumizone for 3 generations. However, the inhibitor of P450s or GSTs only has slight synergism on metaflumizone toxicity against resistant populations, and there are no obvious differences in activities of P450s or GSTs between resistant populations and the susceptible strain. These results suggest that esterases might take pivotal role in conferring metabolic resistance to metaflumizone in the field populations of S. exigua, and P450s or GSTs are not involved in this resistance. Moreover, flavin-dependent monooxygenases (FMOs) are discovered to involve in metaflumizone resistance in the field populations of S. exigua. The FMO inhibitor, methimazole, potentiates metaflumizone toxicity in resistant larva of this species substantially. The synergism ratios for methimazole in resistant populations HZ11 and HZ12 were 3.1 and 1.9, respectively. Enzymatic assays also revealed higher FMO activities in resistant populations than in the susceptible strain, and successive selection with metaflumizone further increased the FMO activity in the field resistant population, but not significantly. The higher FMO activities in the older larval stages and in the larval midgut signify the importance of FMO in the detoxification of xenobiotic from food sources. The synergism assay and FMO activity analysis suggest that FMO contributes to metaflumizone detoxification in resistant populations of S. exigua and conferred metaflumizone resistance in S. exigua. A novel mechanism for insecticide resistance by insect was proposed.
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Affiliation(s)
- Xiangrui Tian
- Department of Pesticide Science, College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China
| | - Xingxing Sun
- Department of Pesticide Science, College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China
| | - Jianya Su
- Department of Pesticide Science, College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China.
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19
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Abstract
CONTEXT Metaflumizone is a voltage-dependent sodium channel blocker insecticide, which is chemically similar to indoxacarb. Although indoxacarb poisoning is known as a cause of methemoglobinemia, the effect of metaflumizone poisoning in humans is still unknown. CASE DETAILS A 57-year-old man presented with a decreased mentality following ingestion of 100 ml of metaflumizone, 150 ml of glyphosate and alcohol. Although initial methemoglobin (MetHb) level was slightly higher than the normal limit, it gradually rose to reach a maximum level of 27.8%, on the 19 h after ingestion. After hemodialysis, MetHb level was reduced to 15.8%, which decreased further to the level of 6%, following methylene blue administration. DISCUSSION Metaflumizone shares a similar chemical structure to indoxacarb, which is known to be a cause of methemoglobinemia. Physicians should be alert for the development of methemoglobinemia in symptomatic patients when facing potential pesticide poisoning such as metaflumizone poisoning.
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Affiliation(s)
- J S Oh
- Department of Emergency Medicine, College of Medicine, The Catholic University of Korea , Seoul , Republic of Korea
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20
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Silver KS, Du Y, Nomura Y, Oliveira EE, Salgado VL, Zhorov BS, Dong K. Voltage-Gated Sodium Channels as Insecticide Targets. ADVANCES IN INSECT PHYSIOLOGY 2014; 46:389-433. [PMID: 29928068 PMCID: PMC6005695 DOI: 10.1016/b978-0-12-417010-0.00005-7] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Voltage-gated sodium channels are critical for the generation and propagation of action potentials. They are the primary target of several classes of insecticides, including DDT, pyrethroids and sodium channel blocker insecticides (SCBIs). DDT and pyrethroids preferably bind to open sodium channels and stabilize the open state, causing prolonged currents. In contrast, SCBIs block sodium channels by binding to the inactivated state. Many sodium channel mutations are associated with knockdown resistance (kdr) to DDT and pyrethroids in diverse arthropod pests. Functional characterization of kdr mutations together with computational modelling predicts dual pyrethroid receptor sites on sodium channels. In contrast, the molecular determinants of the SCBI receptor site remain largely unknown. In this review, we summarize current knowledge about the molecular mechanisms of action of pyrethroids and SCBIs, and highlight the differences in the molecular interaction of these insecticides with insect versus mammalian sodium channels.
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Affiliation(s)
- Kristopher S Silver
- Department of Anatomy and Physiology, Kansas State University, Manhattan, Kansas, USA
| | - Yuzhe Du
- Department of Entomology, Neuroscience and Genetics Programs, Michigan State University, East Lansing, Michigan, USA
| | - Yoshiko Nomura
- Department of Entomology, Neuroscience and Genetics Programs, Michigan State University, East Lansing, Michigan, USA
| | - Eugenio E Oliveira
- Departamento de Entomologia, Universidade Federal de Vic¸osa, Vic¸osa, Minas Gerais, Brasil
| | - Vincent L Salgado
- BASF Agricultural Products, BASF Corporation, Research Triangle Park, North Carolina, USA
| | - Boris S Zhorov
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
- Sechenov Institute of Evolutionary Physiology & Biochemistry, Russian Academy of Sciences, St. Petersburg, Russia
| | - Ke Dong
- Department of Entomology, Neuroscience and Genetics Programs, Michigan State University, East Lansing, Michigan, USA
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Sparks TC. Insecticide discovery: an evaluation and analysis. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2013; 107:8-17. [PMID: 25149229 DOI: 10.1016/j.pestbp.2013.05.012] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2013] [Revised: 05/22/2013] [Accepted: 05/22/2013] [Indexed: 05/05/2023]
Abstract
There is an on-going need for the discovery and development of new insecticides due to the loss of existing products through the development of resistance, the desire for products with more favorable environmental and toxicological profiles, shifting pest spectrums, and changing agricultural practices. Since 1960, the number of research-based companies in the US and Europe involved in the discovery of new insecticidal chemistries has been declining. In part this is a reflection of the increasing costs of the discovery and development of new pesticides. Likewise, the number of compounds that need to be screened for every product developed has, until recently, been climbing. In the past two decades the agrochemical industry has been able to develop a range of new products that have more favorable mammalian vs. insect selectivity. This review provides an analysis of the time required for the discovery, or more correctly the building process, for a wide range of insecticides developed during the last 60 years. An examination of the data around the time requirements for the discovery of products based on external patents, prior internal products, or entirely new chemistry provides some unexpected observations. In light of the increasing costs of discovery and development, coupled with fewer companies willing or able to make the investment, insecticide resistance management takes on greater importance as a means to preserve existing and new insecticides.
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Affiliation(s)
- Thomas C Sparks
- Dow AgroSciences, Discovery Research, 9330 Zionsville Road, Indianapolis, IN 46268, USA.
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22
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Roditakis E, Skarmoutsou C, Staurakaki M. Toxicity of insecticides to populations of tomato borer Tuta absoluta (Meyrick) from Greece. PEST MANAGEMENT SCIENCE 2013; 69:834-840. [PMID: 23757288 DOI: 10.1002/ps.3442] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2012] [Revised: 09/21/2012] [Accepted: 10/19/2012] [Indexed: 06/02/2023]
Abstract
BACKGROUND Tuta absoluta (Meyrick), in only a few years, has become a serious threat to global tomato production. Depending on the cropping system and infestation pressure, T. absoluta control may rely heavily on insecticide applications. By means of a validated IRAC bioassay method, the toxicity of all insecticides registered for T. absoluta control in Greece has been estimated. A non-registered pyrethroid insecticide was also included in this study. RESULTS Low heterogeneity was detected in the populations tested with most insecticides. The LC50 ranged from 0.31 to 1.31 mg L(-1) for flubendiamide, from 0.12 to 0.53 mg L(-1) for chlorantraniliprole, from 0.03 to 0.12 mg L(-1) for emamectin benzoate, from 0.08 to 0.26 mg L(-1) for spinosad, from 31.8 to 159.5 mg L(-1) for metaflumizone, from 1.73 to 17.5 mg L(-1) for indoxacarb, from 530 to 2038 mg L(-1) for chlorpyriphos and finally from 475 to 794 mg L(-1) for cypermethrin. The variability of the LC50 values among the tested populations was low (RR under 5×), except for indoxacarb (RR = 10×). In the absence of a reference strain, comparisons with the recommended label rates were performed. Evidence of potential control failures was detected using probit analysis estimates for cypermethrin, chlorpyriphos and metaflumizone. CONCLUSIONS For most registered insecticides, a solid set of baseline data has been presented that can be used in future resistance monitoring studies. The interaction of metaflumizone with T. absoluta has been discussed, and for chlorpyriphos it is suspected that the resistance level is underestimated with the present dataset. Finally, it has been demonstrated that the pyrethroid cypermethrin would provide insufficient control of the pest.
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Affiliation(s)
- Emmanouil Roditakis
- Hellenic Agricultural Organisation - Demeter (former NAGREF), Plant Protection Institute of Heraklion, Heraklion, Greece.
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von Stein RT, Silver KS, Soderlund DM. Indoxacarb, Metaflumizone, and Other Sodium Channel Inhibitor Insecticides: Mechanism and Site of Action on Mammalian Voltage-Gated Sodium Channels. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2013; 106:101-112. [PMID: 24072940 PMCID: PMC3780446 DOI: 10.1016/j.pestbp.2013.03.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Sodium channel inhibitor (SCI) insecticides were discovered almost four decades ago but have only recently yielded important commercial products (eg., indoxacarb and metaflumizone). SCI insecticides inhibit sodium channel function by binding selectively to slow-inactivated (non-conducting) sodium channel states. Characterization of the action of SCI insecticides on mammalian sodium channels using both biochemical and electrophysiological approaches demonstrates that they bind at or near a drug receptor site, the "local anesthetic (LA) receptor." This mechanism and site of action on sodium channels differentiates SCI insecticides from other insecticidal agents that act on sodium channels. However, SCI insecticides share a common mode of action with drugs currently under investigation as anticonvulsants and treatments for neuropathic pain. In this paper we summarize the development of the SCI insecticide class and the evidence that this structurally diverse group of compounds have a common mode of action on sodium channels. We then review research that has used site-directed mutagenesis and heterologous expression of cloned mammalian sodium channels in Xenopus laevis oocytes to further elucidate the site and mechanism of action of SCI insecticides. The results of these studies provide new insight into the mechanism of action of SCI insecticides on voltage-gated sodium channels, the location of the SCI insecticide receptor, and its relationship to the LA receptor that binds therapeutic SCI agents.
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Affiliation(s)
| | | | - David M. Soderlund
- Corresponding author at: Department of Entomology, Cornell University, 630 W. North Street, Geneva, NY 14456, USA. Tel: +1 315 787-2364. Fax: +1 315 787 2326.
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Chatterjee NS, Gupta S. Persistence of metaflumizone on cabbage (Brassica oleracea Linne) and soil, and its risk assessment. ENVIRONMENTAL MONITORING AND ASSESSMENT 2013; 185:6201-6208. [PMID: 23224645 DOI: 10.1007/s10661-012-3017-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2012] [Accepted: 11/20/2012] [Indexed: 06/01/2023]
Abstract
Metaflumizone is a novel sodium channel blocker insecticide of semicarbazone class. It provides good to excellent control of most of the economically important lepidopterous pests and certain pests in the orders Coleoptera, Hemiptera, Hymenoptera, Diptera, Isoptera, and Siphonaptera. Although metaflumizone has been marketed globally for several years and got registered in India in the year 2009, specifically for the control of DBM on cabbage, to our knowledge, no food safety aspects of metaflumizone residue on cabbage have ever been reported in the literature in India or elsewhere. The present study was undertaken to evaluate the persistence of metaflumizone on cabbage and soil, vis-a-vis its risk assessment, following two spray applications of metaflumizone 220 SC (Verismo®), each at recommended and double dose of 200 and 400 g a.i. ha(-1) respectively. Initial residue deposits of metaflumizone on cabbage were 0.46 and 0.51 mg kg(-1) at recommended and 0.76 and 0.85 mg kg(-1) at double the recommended dose following the first spray and second spray application. The residues persisted beyond 5 days from both the treatments and dissipated with the half-life ranging from 1.7-2.1 days. Initial deposits of metaflumizone on soil ranged from 0.23-0.37 mg kg(-1) and degraded with a half life ranging from 4.0-4.8 days. No degradation product of metaflumizone was detected in cabbage and soil at any point of time. Soil samples collected from the treated field after 7 days were free from any residue of metaflumizone or its metabolites. A pre-harvest waiting period of 3 days after application was suggested based on calculation of theoretical maximum daily intake.
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Affiliation(s)
- Niladri Sekhar Chatterjee
- Division of Agricultural Chemicals, Indian Agricultural Research Institute, New Delhi, 110012, India
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Chatterjee NS, Gupta S, Varghese E. Degradation of metaflumizone in soil: impact of varying moisture, light, temperature, atmospheric CO2 level, soil type and soil sterilization. CHEMOSPHERE 2013; 90:729-36. [PMID: 23102725 DOI: 10.1016/j.chemosphere.2012.09.057] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2012] [Revised: 09/03/2012] [Accepted: 09/18/2012] [Indexed: 05/14/2023]
Abstract
Soil is a major sink for the bulk of globally used pesticides. Hence, fate of pesticides in soil under the influence of various biotic and abiotic factors becomes important for evaluation of stability and safety. This paper presents the impact of varying moisture, light, temperature, atmospheric CO(2) level, soil type and soil sterilization on degradation of metaflumizone, a newly registered insecticide in India. Degradation of metaflumizone in soil followed the first order reaction kinetics and its half life values varied from ~20 to 150 d. Under anaerobic condition, degradation of metaflumizone was faster (t(½) 33.4 d) compared to aerobic condition (t(½) 50.1 d) and dry soil (t(½) 150.4 d). Under different light exposures, degradation was the fastest under UV light (t(½) 27.3 d) followed by Xenon light (t(½) 43 d) and dark condition (t(½) 50.1 d). Degradation rate of metaflumizone increased with temperature and its half life values ranged from 30.1 to 100.3d. Elevated atmospheric CO(2) level increased the degradation in soil (t(½) 20.1-50.1 d). However, overall degradation rate was the fastest at 550 ppm atmospheric CO(2) level, followed by 750 ppm and ambient level (375 ppm). Degradation of metaflumizone was faster in Oxisol (pH 5.2, Total Organic Carbon 1.2%) compared to Inceptisol (pH 8.15, TOC 0.36%). In sterile soil, only 5% dissipation of initial concentration was observed after 90 d of sampling. Under various conditions, 4-cyanobenzoic acid (0.22-1.86 mg kg(-1)) and 4-trifluoromethoxy aniline (0.21-1.23 mg kg(-1)) were detected as major degradation products.
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Affiliation(s)
- Niladri Sekhar Chatterjee
- Division of Agricultural Chemicals, Indian Agricultural Research Institute, New Delhi 110 012, India.
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Li C, Yang T, Wu YL. Degradation of metaflumizone in rice, water and soil under field conditions. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2012; 86:73-78. [PMID: 23079740 DOI: 10.1016/j.ecoenv.2012.08.029] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2012] [Revised: 08/04/2012] [Accepted: 08/07/2012] [Indexed: 06/01/2023]
Abstract
The degradation behavior of metaflumizone was studied in a rice field ecosystem, and a simple and reliable analytical method was developed for determination of metaflumizone in soil, rice straw, paddy water and brown rice. Metaflumizone residues were extracted from samples with acetonitrile. The extract was cleaned up with QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) method, and determined by liquid chromatography electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS). The average recoveries of metaflumizone were 75.2-105.1 percent from soil, rice straw, paddy water and brown rice. The relative standard deviations were less than 15 percent. The limits of quantitation (LOQs) of metaflumizone were 3.0μg/L for paddy water and 3.0μg/kg for other samples. The results of the kinetic study of metaflumizone residue showed that metaflumizone degradation in soil, water and rice straw coincided with C=0.08564e(-0.0505t), C=0.04984e(-0.1982t), C=2.2572e(-0.1533t), respectively; the half-lives were about 13.7d, 3.5d, and 4.5d, respectively. The final residues of metaflumizone on brown rice were lower than maximum residue limit (MRL) of 0.05mg/kg after 28d Pre-Harvest Interval (PHI) at the recommended dosage. Therefore, a dosage of 450mLa.i.ha(-1) with 28 days before harvest was recommended, which could be considered as safe to human beings and animals.
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Affiliation(s)
- Cun Li
- Tianjin Agricultural University, Tianjin 300380, PR China
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Antifungal, mosquito deterrent, and larvicidal activity of N-(benzylidene)-3-cyclohexylpropionic acid hydrazide derivatives. Med Chem Res 2012. [DOI: 10.1007/s00044-012-0250-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Sun R, Li Y, Xiong L, Liu Y, Wang Q. Design, synthesis, and insecticidal evaluation of new benzoylureas containing isoxazoline and isoxazole group. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2011; 59:4851-4859. [PMID: 21438557 DOI: 10.1021/jf200395g] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Twenty-two new benzoylphenylureas containing isoxazoline and the isoxazole group were designed and synthesized, and their structures were characterized by (1)H NMR and elemental analysis (or HRMS). The larvicidal activities against Oriental armyworm, mosquito, and diamondback moth of the new compounds were evaluated. Compounds I-1 and III-1 showed nearly the same level of insecticidal activity against Oriental armyworm as commercial insecticide Flucycloxuron and surprisingly exhibited much higher larvicidal activities against diamondback moth than Flucycloxuron.
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Affiliation(s)
- Ranfeng Sun
- State Key Laboratory of Elemento-Organic Chemistry, Institute of Elemento-Organic Chemistry, Nankai University, Tianjin, People's Republic of China
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Silver KS, Song W, Nomura Y, Salgado VL, Dong K. Mechanism of action of sodium channel blocker insecticides (SCBIs) on insect sodium channels. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2010; 97:87-92. [PMID: 24013950 PMCID: PMC3765036 DOI: 10.1016/j.pestbp.2009.09.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Sodium channel blocker insecticides (SCBIs) are a relatively new class of insecticides, with a mechanism of action different from those of other classes of insecticides that target voltage-gated sodium channels. These compounds have no effect at hyperpolarized membrane potentials, but cause a voltage-dependent, nearly irreversible block as the membrane potential is depolarized. The mechanism of action of SCBIs is similar to that of local anesthetics (LAs), class I anticonvulsants and class I antiarrhythmics. In this article, we review the physiological actions of these compounds on the whole animal, the nervous system and sodium channels, and also present the results from recent studies that elucidate the receptor site of SCBIs.
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Affiliation(s)
- Kristopher S. Silver
- Department of Entomology, Genetics and Neuroscience Programs, Michigan State University, East Lansing, MI, 48824, USA
| | - Weizhong Song
- Department of Entomology, Genetics and Neuroscience Programs, Michigan State University, East Lansing, MI, 48824, USA
| | - Yoshiko Nomura
- Department of Entomology, Genetics and Neuroscience Programs, Michigan State University, East Lansing, MI, 48824, USA
| | - Vincent L. Salgado
- BASF Agricultural Products, BASF Corporation, 26 Davis Drive, Research Triangle Park, NC 27709, USA
- Corresponding authors: Ke Dong: ; Vincent L. Salgado:
| | - Ke Dong
- Department of Entomology, Genetics and Neuroscience Programs, Michigan State University, East Lansing, MI, 48824, USA
- Corresponding authors: Ke Dong: ; Vincent L. Salgado:
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Dong F, Liu X, Cheng L, Chen W, Li J, Qin D, Zheng Y. Determination of metaflumizone residues in cabbage and soil using ultra-performance liquid chromatography/ESI-MS/MS. J Sep Sci 2009; 32:3692-7. [DOI: 10.1002/jssc.200900338] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Hellmann K, Adler K, Parker L, Pfister K, DeLay RL, Rugg D. Evaluation of the efficacy and safety of a novel formulation of metaflumizone in cats naturally infested with fleas in Europe. Vet Parasitol 2007; 150:246-50. [PMID: 17931784 DOI: 10.1016/j.vetpar.2007.08.041] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The efficacy and safety of a novel spot-on formulation of metaflumizone (ProMeris for Cats, Fort Dodge Animal Health, Overland Park, KS) was assessed in cats naturally infested with fleas in a multiregional, clinical field study. Sixteen veterinary clinics in Germany and eight clinics in France enrolled patients to the study. A total of 173 cats with flea infestation qualified as primary patients and were randomly allocated to one of the two treatments in a ratio of approximately 2:1 for metaflumizone (minimum dosage of 40mg/kg) or fipronil (at the recommended label rate). Clinical examinations and baseline parasite counts were performed on Day 0 prior to treatment. Flea counts and safety evaluations were repeated at approximately 2-week intervals for 8 weeks. Both treatments resulted in consistent reductions (>84%) in flea numbers throughout the study, but metaflumizone resulted in numerically higher reductions on most count days. Within groups the flea reduction was highly significant (p<0.0001) compared to baseline at all observation periods. The efficacy of metaflumizone against fleas compared to baseline was 91.0%, 89.4%, 90.8% and 90.7% at Day 14, 28, 42 and 56, respectively. The corresponding efficacies for fipronil were 91.7%, 86.9%, 84.6% and 87.7%. Metaflumizone was highly effective in controlling existing infestations of fleas on cats and was effective against reinfestation for at least 56 days. Metaflumizone showed a good tolerance profile in cats.
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Affiliation(s)
- K Hellmann
- KLIFOVET AG, Geyerspergerstr. 27, D-80689 Munich, Germany
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Hellmann K, Adler K, Parker L, Pfister K, DeLay R, Rugg D. Evaluation of the efficacy and safety of a novel formulation of metaflumizone plus amitraz in dogs naturally infested with fleas and ticks in Europe. Vet Parasitol 2007; 150:239-45. [DOI: 10.1016/j.vetpar.2007.08.040] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Confirmation of the efficacy of a novel formulation of metaflumizone plus amitraz for the treatment and control of fleas and ticks on dogs. Vet Parasitol 2007; 150:209-18. [DOI: 10.1016/j.vetpar.2007.08.035] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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DeLay RL, Lacoste E, Delprat S, Blond-Riou F. Pharmacokinetics of metaflumizone in the plasma and hair of cats following topical application. Vet Parasitol 2007; 150:258-62. [PMID: 17913364 DOI: 10.1016/j.vetpar.2007.08.042] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Controlled laboratory studies have shown that a novel spot-on formulation containing 20% (w/v) metaflumizone (ProMeris for Cats, Fort Dodge Animal Health, Overland Park, KS) is effective for the treatment and control of fleas on cats. Two studies were conducted to determine the distribution of metaflumizone in the plasma and hair of cats following treatment at the minimum recommended dose of 40mg/kg. Six purpose-bred cats, three males and three females, were used in each study. Plasma or hair samples were collected from each cat just prior to dosing and periodically through 56 days after treatment. Samples were analyzed by HPLC methods validated for the determination of metaflumizone. Metaflumizone concentrations in plasma were below the method limit of quantification (<50ng/ml) in all samples but one, and were frequently not detectable (<1.1ng/ml). Plasma collected 3 days post-treatment from one cat had a metaflumizone concentration of 57.8ng/ml. The frequency of measurable levels of metaflumizone in the plasma was too low to allow the calculation of pharmacokinetic parameters. Analysis of hair samples indicated that metaflumizone was widely distributed in the hair coat of the cat within 1 day after administration, reaching maximum concentrations within 1 or 2 days post-treatment. Low but quantifiable levels were still present at the end of the 56-day study. Data from the present studies indicate that the ectoparasitic activity is due to exposure of the parasites to metaflumizone on the surface of the host (skin and hair), not to exposure via the circulatory system of the host.
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Affiliation(s)
- R L DeLay
- Fort Dodge Animal Health, P.O. Box 5366, Princeton, NJ 08543, USA.
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DeLay R, Lacoste E, Mezzasalma T, Blond-Riou F. Pharmacokinetics of metaflumizone and amitraz in the plasma and hair of dogs following topical application. Vet Parasitol 2007; 150:251-7. [DOI: 10.1016/j.vetpar.2007.08.045] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Holzmer S, Hair JA, Dryden MW, Young DR, Carter L. Efficacy of a novel formulation of metaflumizone for the control of fleas (Ctenocephalides felis) on cats. Vet Parasitol 2007; 150:219-24. [PMID: 17931782 DOI: 10.1016/j.vetpar.2007.08.037] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
A novel spot-on formulation containing metaflumizone (ProMeris for Cats, Fort Dodge Animal Health, Overland Park, KS) was evaluated in five laboratory studies to determine the duration of residual efficacy in cats against fleas after a single spot treatment. In each study, eight domestic shorthair cats were randomly allocated to each treatment group and individually housed. One group in each study remained non-treated. In one study, an additional group of eight cats was treated with a placebo formulation. Cats were treated topically with metaflumizone formulation to provide a dose of at least 40mg metaflumizone/kg. Cats were infested with 100 cat fleas (Ctenocephalides felis felis) once per week for approximately 8 weeks. Cats were comb counted 48h after treatment and each infestation to determine the number of viable fleas present. There were no significant differences in flea counts between the non-treated control and the placebo-treated control (P>0.05) other than a 26% reduction at week 1, demonstrating that the formulation excipients had no activity. Metaflumizone treatment resulted in significantly lower flea numbers relative to non-treated controls on all post-treatment count days (P<0.05). Metaflumizone provided >90% control of flea infestations up to 7 weeks following a single treatment.
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Affiliation(s)
- S Holzmer
- Fort Dodge Animal Health, P.O. Box 5366, Princeton, NJ 08543, USA.
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