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Luker HA. A critical review of current laboratory methods used to evaluate mosquito repellents. FRONTIERS IN INSECT SCIENCE 2024; 4:1320138. [PMID: 38469342 PMCID: PMC10926509 DOI: 10.3389/finsc.2024.1320138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Accepted: 01/02/2024] [Indexed: 03/13/2024]
Abstract
Pathogens transmitted by mosquitoes threaten human health around the globe. The use of effective mosquito repellents can protect individuals from contracting mosquito-borne diseases. Collecting evidence to confirm and quantify the effectiveness of a mosquito repellent is crucial and requires thorough standardized testing. There are multitudes of methods to test repellents that each have their own strengths and weaknesses. Determining which type of test to conduct can be challenging and the collection of currently used and standardized methods has changed over time. Some of these methods can be powerful to rapidly screen numerous putative repellent treatments. Other methods can test mosquito responses to specific treatments and measure either spatial or contact repellency. A subset of these methods uses live animals or human volunteers to test the repellency of treatments. Assays can greatly vary in their affordability and accessibility for researchers and/or may require additional methods to confirm results. Here I present a critical review that covers some of the most frequently used laboratory assays from the last two decades. I discuss the experimental designs and highlight some of the strengths and weaknesses of each type of method covered.
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Affiliation(s)
- Hailey A. Luker
- Molecular Vector Physiology Laboratory, Department of Biology, New Mexico State University, Las Cruces, NM, United States
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2
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Norris EJ, Kline J, Bloomquist JR. Repellency and Toxicity of Vapor-Active Benzaldehydes against Aedes aegypti. ACS Infect Dis 2024; 10:120-126. [PMID: 38099713 DOI: 10.1021/acsinfecdis.3c00294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2024]
Abstract
Chemical screening efforts recently found that 3-phenoxybenzaldehyde, a breakdown product of alpha-cyano pyrethroids, was a potent spatial repellent against Aedes aegypti mosquitoes in a glass tube repellency assay. In order to characterize this molecule further and identify structure-activity relationships, a set of 12 benzaldehyde analogues were screened for their repellency and toxicity in vapor phase exposures at 100 μg/cm2. Dose-response analyses were performed for the most active compounds in order to better characterize their repellent potency and toxicity compared to those of other commercially available toxicants. The three most toxic compounds (LC50 values) were 3-chlorobenzaldehyde (CBA) (37 μg/cm2), biphenyl-3-carboxaldehyde (BCA) (48 μg/cm2), and 3-vinylbenzaldehyde (66 μg/cm2), which makes them less toxic than bioallethrin (6.1 μg/cm2) but more toxic than sandalwood oil (77 μg/cm2), a repellent/toxic plant essential oil. The most repellent analogues with EC50 values below 30 μg/cm2 were 3-phenoxybenzaldehyde (6.3 μg/cm2), isophthalaldehyde (23 μg/cm2), BCA (17 μg/cm2), and CBA (22 μg/cm2), which makes them about as active as N,N-diethyl-3-methylbenzamide (25.4 μg/cm2). We further investigated the activity of a select group of these benzaldehydes to block the firing of the central nervous system of A. aegypti larvae. Compounds most capable of repelling and killing mosquitoes in the vapor phase were also those most capable of blocking nerve firing in the larval mosquito nervous system. The results demonstrate that benzaldehyde analogues are viable candidate repellent and insecticidal molecules and may lead to the development of future repellent and vapor toxic vector control tools.
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Affiliation(s)
- Edmund J Norris
- Center for Medical, Agricultural, and Veterinary Entomology, United States Department of Agriculture-Agricultural Research Service, Gainesville, Florida 32608, United States
- Emerging Pathogens Institute, Department of Entomology and Nematology, University of Florida, Gainesville, Florida 32610, United States
| | - Jedidiah Kline
- Center for Medical, Agricultural, and Veterinary Entomology, United States Department of Agriculture-Agricultural Research Service, Gainesville, Florida 32608, United States
| | - Jeffrey R Bloomquist
- Emerging Pathogens Institute, Department of Entomology and Nematology, University of Florida, Gainesville, Florida 32610, United States
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3
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Devillers J, Larghi A, Sartor V, Setier-Rio ML, Lagneau C, Devillers H. Nonlinear SAR Modelling of Mosquito Repellents for Skin Application. TOXICS 2023; 11:837. [PMID: 37888688 PMCID: PMC10610853 DOI: 10.3390/toxics11100837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Revised: 09/28/2023] [Accepted: 09/29/2023] [Indexed: 10/28/2023]
Abstract
Finding new marketable mosquito repellents is a complex and time-consuming process that can be optimized via modelling. In this context, a SAR (Structure-Activity Relationship) model was designed from a set of 2171 molecules whose actual repellent activity against Aedes aegypti was available. Information-rich descriptors were used as input neurons of a three-layer perceptron (TLP) to compute the models. The most interesting classification model was a 20/6/2 TLP showing 94% and 89% accuracy on the training set and test set, respectively. A total of 57 other artificial neural network models based on the same architecture were also computed. This allowed us to consider all chemicals both as training and test set members in order to better interpret the results obtained with the selected model. Most of the wrong predictions were explainable. The 20/6/2 TLP model was then used for predicting the potential repellent activity of new molecules. Among them, two were successfully evaluated in vivo.
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Affiliation(s)
| | - Adeline Larghi
- EID Méditerranée, Direction Technique, 34184 Montpellier, France
| | - Valérie Sartor
- Laboratoire des IMRCP, Université de Toulouse, CNRS UMR 5623, Université Toulouse III-Paul Sabatier, 31062 Toulouse, France
| | | | | | - Hugo Devillers
- SPO, University Montpellier, INRAE, Institut Agro, 34000 Montpellier, France
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4
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Agnew J, Gorzelski A, Zhu J, Romero A. Coconut fatty acids exhibit strong repellency and week-long efficacy against several urban pest arthropods of the southwestern United States. PEST MANAGEMENT SCIENCE 2023; 79:3511-3519. [PMID: 37144346 DOI: 10.1002/ps.7531] [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: 11/08/2022] [Revised: 03/06/2023] [Accepted: 05/02/2023] [Indexed: 05/06/2023]
Abstract
BACKGROUND The southwestern United States is home to a variety of arthropods including Turkestan cockroaches, Blatta lateralis (Walker); hematophagous kissing bugs, Tritoma rubida (Uhler); and Arizona bark scorpions, Centruroides sculpturatus Ewing. These arthropods cause medical concern when they become established around homes and/or invade indoors. Traditionally, the management of these pests has relied primarily on the use of chemical insecticides; however, they offer poor prospects for control owing to their lack of efficacy as well as the effects of insecticides on humans and the environment. Botanical repellents are an option that has not been fully investigated for the management of these pests. Here, we investigated the behavioral responses of common urban pests of the southwestern USA to recently discovered coconut fatty acids (CFAs), to establish the potential use of these compounds as repellents. RESULTS Fresh residues of CFA mixture (CFAm) and their constituents caprylic acid, capric acid, capric acid methyl ester, lauric acid, and lauric acid methyl ester, tested at a concentration of 1 mg cm-2 , strongly repelled all arthropods. The repellent activity of CFAm lasted for at least 7 days, and the addition of lavender oil, used as an odor-masking agent, did not decrease this effect. Concentrations of CFAm ten times lower (0.1 mg cm-2 ) still repelled Turkestan cockroaches, and concentrations 100 times lower (0.01 mg cm-2 ) repelled T. rubida and scorpions. CONCLUSIONS CFAm and some of their constituents are efficacious, economical, and logistically feasible for inclusion in integrated pest management programs for these important urban pests of the southwestern USA. © 2023 Society of Chemical Industry.
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Affiliation(s)
- John Agnew
- Department of Entomology, Plant Pathology and Weed Science, New Mexico State University, Las Cruces, NM, USA
| | - Ashton Gorzelski
- Department of Biology, New Mexico State University, Las Cruces, NM, USA
| | - Junwei Zhu
- United States Department of Agriculture, Agricultural Research Service, Agroecosystem Management Research Unit, University of Nebraska, Lincoln, NE, USA
| | - Alvaro Romero
- Department of Entomology, Plant Pathology and Weed Science, New Mexico State University, Las Cruces, NM, USA
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Roth MA, Lahondère C, Gross AD. Discovering Aethina tumida responses to attractant and repellent molecules: A potential basis for future management strategies. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2023; 192:105386. [PMID: 37105615 DOI: 10.1016/j.pestbp.2023.105386] [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: 12/23/2022] [Revised: 02/21/2023] [Accepted: 03/06/2023] [Indexed: 06/19/2023]
Abstract
Small hive beetle (Aethina tumida) management has been highly dependent upon chemical and mechanical control over the past two decades; however, many of these methods have not been consistently effective or safe for European honey bee (Apis mellifera) colonies. Here we explore the behavioral and physiological effects of the attractants isopentyl acetate and pollen patty upon A. tumida adults, and also investigate the mixture of attractants with repellent compounds, which were previously untested against A. tumida. Electroantennograms established sensitivity of A. tumida antennae to both attractants and all repellents with the exception of DEET, with antennae displaying greatest sensitivity to the repellent pyrrolidine. A walking-response olfactometer, designed specifically for A. tumida, was used for all behavioral experiments. It was found that both pollen patty and isopentyl acetate were attractive to A. tumida adults; conversely, mixes of attractants and repellent volatiles led to less attraction or avoidance of what was previously a significantly attractive source. Of all repellents tested, pyrrolidine was found to be the most repelling molecule, with significant avoidance of the attractive source at a 10 mg treatment of pyrrolidine. The results of this study indicate that, at the behavioral level, the repellent compounds pyrrolidine and 1,4-dimethylpiperazine resulted in a negative preference index indicating a repellent behavioral response. By strategically implementing a repellent source in an apiary environment, A. tumida adults could be deterred from entering and invading hives.
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Affiliation(s)
- Morgan A Roth
- Molecular Physiology and Toxicology Laboratory, Department of Entomology, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, United States of America
| | - Chloé Lahondère
- Department of Biochemistry, Virginia Polytechnic and State University, Blacksburg, VA 24061, United States of America
| | - Aaron D Gross
- Molecular Physiology and Toxicology Laboratory, Department of Entomology, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, United States of America.
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Farouil L, Duchaudé Y, Zozo L, Sylvestre M, Lafay F, Marote P, Cebrián-Torrejón G. Cyclic voltammetry of immobilized particles as an alternative pesticide screening method for Aedes aegypti mosquitoes. J Solid State Electrochem 2023. [DOI: 10.1007/s10008-023-05398-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
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7
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Iovinella I, Mandoli A, Luceri C, D’Ambrosio M, Caputo B, Cobre P, Dani FR. Cyclic Acetals as Novel Long-Lasting Mosquito Repellents. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2023; 71:2152-2159. [PMID: 36649540 PMCID: PMC9896555 DOI: 10.1021/acs.jafc.2c05537] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/06/2022] [Revised: 12/30/2022] [Accepted: 01/03/2023] [Indexed: 06/17/2023]
Abstract
The use of skin repellents against hematophagous mosquitoes is an important personal protection practice wherever these insects are abundant and where they are vectors of diseases. DEET and Icaridin are the major synthetic insect repellents in commercial formulations and are considered the most effective. Here, we tested against the mosquito Aedes albopictus several cyclic hydroxyacetals synthesized by acetalization of commercially available aliphatic carbonyl compounds (ranging from C3 to C15) with either glycerol, 1,1,1-trismethyloletane, or 1,1,1-trismethylolpropane and compared their efficacy with commercial repellents. We found that several hydroxyacetals were comparable with DEET and Icaridin both in terms of the required dose and repellence duration, while a few performed better. For those most active, toxicity was investigated, finding that a few of them were less cytotoxic than DEET and less prone to permeate through cell layers. Therefore, such results indicate that novel safe mosquito repellents could be developed among cyclic hydroxyacetals.
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Affiliation(s)
- Immacolata Iovinella
- Biology
Department, University of Firenze, via Madonna del Piano 6, 50019Sesto Fiorentino, Italy
| | - Alessandro Mandoli
- Department
of Chemistry and Industrial Chemistry, University
of Pisa, Via G. Moruzzi
13, 56124Pisa, Italy
| | - Cristina Luceri
- NEUROFARBA
Department, Section of Pharmacology and Toxicology, University of Firenze, Viale Gaetano Pieraccini 6, 50100Firenze, Italy
| | - Mario D’Ambrosio
- NEUROFARBA
Department, Section of Pharmacology and Toxicology, University of Firenze, Viale Gaetano Pieraccini 6, 50100Firenze, Italy
| | - Beniamino Caputo
- Department
of Public Health & Infectious Diseases, University “La Sapienza”, Piazzale Aldo Moro 5, 00185Roma, Italy
| | - Pietro Cobre
- Department
of Public Health & Infectious Diseases, University “La Sapienza”, Piazzale Aldo Moro 5, 00185Roma, Italy
| | - Francesca Romana Dani
- Biology
Department, University of Firenze, via Madonna del Piano 6, 50019Sesto Fiorentino, Italy
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Neto MFA, Campos JM, Cerqueira APM, de Lima LR, Da Costa GV, Ramos RDS, Junior JTM, Santos CBR, Leite FHA. Hierarchical Virtual Screening and Binding Free Energy Prediction of Potential Modulators of Aedes Aegypti Odorant-Binding Protein 1. Molecules 2022; 27:molecules27206777. [PMID: 36296371 PMCID: PMC9612181 DOI: 10.3390/molecules27206777] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 09/27/2022] [Accepted: 09/30/2022] [Indexed: 11/16/2022] Open
Abstract
The Aedes aegypti mosquito is the main hematophagous vector responsible for arbovirus transmission in Brazil. The disruption of A. aegypti hematophagy remains one of the most efficient and least toxic methods against these diseases and, therefore, efforts in the research of new chemical entities with repellent activity have advanced due to the elucidation of the functionality of the olfactory receptors and the behavior of mosquitoes. With the growing interest of the pharmaceutical and cosmetic industries in the development of chemical entities with repellent activity, computational studies (e.g., virtual screening and molecular modeling) are a way to prioritize potential modulators with stereoelectronic characteristics (e.g., pharmacophore models) and binding affinity to the AaegOBP1 binding site (e.g., molecular docking) at a lower computational cost. Thus, pharmacophore- and docking-based virtual screening was employed to prioritize compounds from Sigma-Aldrich® (n = 126,851) and biogenic databases (n = 8766). In addition, molecular dynamics (MD) was performed to prioritize the most potential potent compounds compared to DEET according to free binding energy calculations. Two compounds showed adequate stereoelectronic requirements (QFIT > 81.53), AaegOBP1 binding site score (Score > 42.0), volatility and non-toxic properties and better binding free energy value (∆G < −24.13 kcal/mol) compared to DEET ((N,N-diethyl-meta-toluamide)) (∆G = −24.13 kcal/mol).
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Affiliation(s)
- Moysés F. A. Neto
- Laboratório de Quimioinformática e Avaliação Biológica, Departamento de Saúde, Universidade Estadual de Feira de Santana, Feira de Santana 44036-900, Brazil
| | - Joaquín M. Campos
- Departamento de Química Farmacéutica y Orgánica, Universidad de Granada, 18071 Granada, Spain
- Biosanitary Institute of Granada (ibs.GRANADA), SAS-University of Granada, 18071 Granada, Spain
| | - Amanda P. M. Cerqueira
- Laboratório de Quimioinformática e Avaliação Biológica, Departamento de Saúde, Universidade Estadual de Feira de Santana, Feira de Santana 44036-900, Brazil
| | - Lucio R. de Lima
- Laboratório de Modelagem e Química Computacional, Departamento de Ciências Biológicas e da Saúde, Universidade Federal do Amapá, Macapá 68902-280, Brazil
| | - Glauber V. Da Costa
- Laboratório de Modelagem e Química Computacional, Departamento de Ciências Biológicas e da Saúde, Universidade Federal do Amapá, Macapá 68902-280, Brazil
| | - Ryan Da S. Ramos
- Laboratório de Modelagem e Química Computacional, Departamento de Ciências Biológicas e da Saúde, Universidade Federal do Amapá, Macapá 68902-280, Brazil
| | - Jairo T. Magalhães Junior
- Centro Multidisciplinar, Departamento de Saúde, Universidade Federal do Oeste da Bahia, Barreiras 47100-000, Brazil
| | - Cleydson B. R. Santos
- Laboratório de Modelagem e Química Computacional, Departamento de Ciências Biológicas e da Saúde, Universidade Federal do Amapá, Macapá 68902-280, Brazil
- Correspondence: (C.B.R.S.); (F.H.A.L.)
| | - Franco H. A. Leite
- Laboratório de Quimioinformática e Avaliação Biológica, Departamento de Saúde, Universidade Estadual de Feira de Santana, Feira de Santana 44036-900, Brazil
- Correspondence: (C.B.R.S.); (F.H.A.L.)
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Shelomi M. Thiamine (vitamin B1) as an insect repellent: a scoping review. BULLETIN OF ENTOMOLOGICAL RESEARCH 2022; 112:431-440. [PMID: 35199632 DOI: 10.1017/s0007485321001176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
While the desire for systemic repellents is high, ineffective repellents put one at risk of insect-vectored pathogens. Vitamin B1, or thiamine, has been touted as a systemic insect repellent since 1943, and denounced as an ineffective placebo for just as long. This paper presents a scoping review of 104 relevant case reports, research studies, and review articles to trace the evolution of this idea and identify an evidence-based, scientific consensus. Reports of thiamine's systemic repellency are primarily anecdotal and based on uncontrolled trials and/or used bite symptoms as a proxy for reduced biting. Controlled experiments on insect landing and feeding found no evidence of repellency. Of the 49 relevant review papers, 16 insect bite prevention guidelines, and 4 government documents, none after the 1990s claimed thiamine is a repellent. The findings of this review are that thiamine cannot repel arthropods in any dosage or route of administration. Due to limited available evidence, the possibility that thiamine reduces the subjective symptoms of insect bites cannot currently be ruled out. Unfortunately, many medical professionals and travelers today still believe thiamine may be effective despite the evidence stating otherwise. Continued promotion of debunked repellents on the commercial market poses a serious risk in countries with the endemic, mosquito-vectored disease.
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Affiliation(s)
- Matan Shelomi
- Department of Entomology, National Taiwan University, Taipei, Taiwan
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10
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Abstract
Mosquitoes use multiple cues to locate food sources (animal and plants), mates, and oviposition sites. The sense of smell plays an important role in these behaviors, and olfactory cues are detected primarily by the appendages on the head-in particular, the antennae. Thus, mosquito olfaction can be studied by conducting electroantennogram (EAG) recordings. EAGs have emerged as a reliable technique to screen for bioactive compounds and are useful in the development of attractants and repellents for mosquito population control. Here, we focus on comparing the two main experimental approaches used in the literature (whole-body and whole-head mounting) and highlight key considerations for conducting EAGs in multiple species and for obtaining reliable and reproducible data.
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Affiliation(s)
- Chloé Lahondère
- Department of Biochemistry, Zoonotic and Arthropod-borne Pathogens, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, USA
- The Fralin Life Science Institute, Zoonotic and Arthropod-borne Pathogens, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, USA
- The Global Change Center, Zoonotic and Arthropod-borne Pathogens, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, USA
- Department of Entomology, Zoonotic and Arthropod-borne Pathogens, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, USA
- Center of Emerging, Zoonotic and Arthropod-borne Pathogens, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, USA
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11
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Kritsi E, Liggri PGV, Stamati ECV, Tsitsanou KE, Zographos SE, Michaelakis A, Papachristos D, Zoumpoulakis P. A Combined Computational Methodology for the Discovery of Hit Compounds with Putative Insect Repellency Properties. ChemMedChem 2022; 17:e202200271. [PMID: 35754000 DOI: 10.1002/cmdc.202200271] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2022] [Indexed: 11/11/2022]
Abstract
Mosquitoes and other hematophagous arthropods, the primary vectors of multiple parasites and viruses, are responsible for the transmission of serious diseases to humans. Nowadays, the interest is focused on the development of novel repellents to the existing ones with advanced properties. The present study attempts the discovery of novel hit compounds which may evolve as insect repellents using a combined computational methodology targeting the Odorant Binding Protein 1 (OBP1). The in silico results indicated two compounds, namely coniferyl alcohol and 1,2-diphenyl-2-propanol, which were further evaluated (a) in vitro for their binding affinity to AgamOBP1 and (b) in vivo using dose-depended repellence tests against the aggressive-day biting Aedes albopictus. The combination of in vitro and in vivo results pointed that coniferyl alcohol and 1,2-diphenyl-2-propanol exhibited high binding affinity over OBP1 with 69.4 and 84.7 nM, respectively as well as efficient repellent activity. Compounds were also tested for their dose-depended repellency activity in vivo against Aedes albopictus. Overall, the selected compounds can serve as scaffolds for the development of novel repellents.
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Affiliation(s)
- Eftichia Kritsi
- National Hellenic Research Foundation Institute of Chemical Biology: Ethniko Idryma Ereunon Institouto Chemikes Biologias, Chemical Biology, GREECE
| | - Panagiota G V Liggri
- National Hellenic Research Foundation Institute of Chemical Biology: Ethniko Idryma Ereunon Institouto Chemikes Biologias, Chemical Biology, GREECE
| | - Evgenia C V Stamati
- National Hellenic Research Foundation Institute of Chemical Biology: Ethniko Idryma Ereunon Institouto Chemikes Biologias, Chemical Biology, GREECE
| | - Katerina E Tsitsanou
- National Hellenic Research Foundation Institute of Chemical Biology: Ethniko Idryma Ereunon Institouto Chemikes Biologias, Chemical Biology, GREECE
| | - Spyros E Zographos
- National Hellenic Research Foundation Institute of Chemical Biology: Ethniko Idryma Ereunon Institouto Chemikes Biologias, Chemical Biology, GREECE
| | - Antonios Michaelakis
- Benaki Phytopathological Institute, Scientific Directorate of Entomology and Agricultural Zoology, GREECE
| | - Dimitrios Papachristos
- Benaki Phytopathological Institute, Scientific Directorate of Entomology and Agricultural Zoology, GREECE
| | - Panagiotis Zoumpoulakis
- National Hellenic Research Foundation, Institute of Biology, Medicinal Chemistry and Biotechnology, Vas. Constantinou 48, 11635, Athens, GREECE
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12
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Xu P, Choo YM, Leal WS. Odorant inhibition in mosquito olfaction mediated by inverse agonists. Biochem Biophys Res Commun 2022; 609:156-162. [PMID: 35430419 PMCID: PMC10540603 DOI: 10.1016/j.bbrc.2022.04.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Accepted: 04/05/2022] [Indexed: 11/02/2022]
Abstract
The insect repellent methyl salicylate elicits excitatory responses upon interaction with CquiOR32, an odorant receptor (OR) from the southern house mosquito, Culex quinquefasciatus. By contrast, eucalyptol binds to CquiOR32 to generate electrophysiological and behavioral inhibitory responses. In an attempt to identify CquiOR32 variants displaying more robust inhibitory responses for more accurate current-voltage analysis, we sequenced 31 CquiOR32 clones. In the Xenopus oocyte recording system, CquiOR32V2/CquiOrco-expressing oocytes yielded eucalyptol-elicited outward (inhibitory) currents relatively larger than methyl salicylate-generated inward (excitatory) currents. Rescuing experiments showed that two of the amino acid substitutions in CquiOR32V2 located in a predicted transmembrane helix of the receptor are determinants of the outward/inward ratios. These findings, along with co-stimulus assays, suggest that odorant and inhibitor may bind to the same binding pocket. Current-voltage relationships obtained with standard perfusion buffer and those devoid of Na+ or Cl- indicated that both excitatory and inhibitory currents are mediated, at least in part, by cation. We then concluded that eucalyptol is an inverse agonist, which shifts the open ⇔ closed equilibrium of the receptor toward the closed conformation, thus reducing the spontaneous activity. By contrast, the binding of methyl salicylate shifts the equilibrium towards the open conformation and, consequently, leads to an increase in cation influx.
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Affiliation(s)
- Pingxi Xu
- Department of Molecular and Cellular Biology, University of California-Davis, Davis, CA, 95616, USA
| | - Young-Moo Choo
- Department of Molecular and Cellular Biology, University of California-Davis, Davis, CA, 95616, USA
| | - Walter S Leal
- Department of Molecular and Cellular Biology, University of California-Davis, Davis, CA, 95616, USA.
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Xu P, Choo YM, An S, Leal GM, Leal WS. Mosquito odorant receptor sensitive to natural spatial repellents and inhibitory compounds. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2022; 144:103763. [PMID: 35364281 PMCID: PMC10540633 DOI: 10.1016/j.ibmb.2022.103763] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 03/17/2022] [Accepted: 03/27/2022] [Indexed: 06/14/2023]
Abstract
Previously, we have identified an odorant receptor (OR) from the southern house mosquito Culex quinquefasciatus, CquiOR32, which responded to both odorants (agonists) and inhibitory compounds (antagonists). CquiOR32/CquiOrco-expressing oocytes responded to methyl salicylate and other odorants with inward (regular) currents but gave currents in the reverse direction when challenged with eucalyptol and other inhibitors. To determine whether hitherto unknown ORs show this intrareceptor inhibition, we have now examined two other receptors in the same cluster, CquiOR27 and CquiOR28. We cloned and tested four variants of CquiOR28, but none of the 250 compounds in our panel of odorants, including an Orco ligand candidate (OLC12), elicited inward or upward deflections of the current traces. By contrast, CquiOR27/CquiOrco-expressing oocytes gave robust, dose-dependent inward currents when challenged with γ-octalactone and other odorants. On the other hand, octylamine and other phenolic compounds elicited dose-dependent currents in the reverse direction. When stimulatory and inhibitory compounds were presented in binary mixtures, γ-octalactone-elicited inward currents were attenuated in a dose-dependent manner according to the concentration of octylamine. As part of our chemical ecology approach, we tested the repellency activity of the most potent ligands in the surface landing and feeding assay and a newly reported hand-in cage assay. Protection elicited by γ-octalactone did not differ significantly from that of DEET at the same dose. In the hand-in cage assay, a cream formulation of γ-octalactone showed 97.0 ± 1.3% protection, with 47.6 ± 8.3% and 1.4 ± 0.7% landings per trial in the hands covered with a control and γ-octalactone cream, respectively (N = 8, p = 0.0078, Wilcoxon matched-pairs signed-rank test).
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Affiliation(s)
- Pingxi Xu
- Department of Molecular and Cellular Biology, University of California-Davis, Davis, CA, 95616, USA
| | - Young-Moo Choo
- Department of Molecular and Cellular Biology, University of California-Davis, Davis, CA, 95616, USA
| | - Sunny An
- Department of Molecular and Cellular Biology, University of California-Davis, Davis, CA, 95616, USA
| | - Gabriel M Leal
- Department of Molecular and Cellular Biology, University of California-Davis, Davis, CA, 95616, USA
| | - Walter S Leal
- Department of Molecular and Cellular Biology, University of California-Davis, Davis, CA, 95616, USA.
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Norris EJ, Chen R, Li Z, Geldenhuys W, Bloomquist JR, Swale DR. Mode of action and toxicological effects of the sesquiterpenoid, nootkatone, in insects. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2022; 183:105085. [PMID: 35430075 DOI: 10.1016/j.pestbp.2022.105085] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Revised: 03/16/2022] [Accepted: 03/18/2022] [Indexed: 06/14/2023]
Abstract
Nootkatone, a sesquiterpenoid isolated from Alaskan yellow cedar (Cupressus nootkatensis), is known to possess insect repellent and acaricidal properties and has recently been registered for commercial use by the Environmental Protection Agency. Previous studies failed to elucidate the mechanism of action of nootkatone, but we found a molecular overlay of picrotoxinin and nootkatone indicated a high degree of structural and electrostatic similarity. We therefore tested the hypothesis that nootkatone was a GABA-gated chloride channel antagonist, similar to picrotoxinin. The KD50 and LD50 of nootkatone on the insecticide-susceptible strain of Drosophila melanogaster (CSOR) showed resistance ratios of 8 and 11, respectively, compared to the cyclodiene-resistant strain of RDL1675, indicating significant cross-resistance. Nootkatone reversed GABA-mediated block of the larval CSOR central nervous system; nerve firing of 78 ± 17% of baseline in the CSOR strain was significantly different from 24 ± 11% of baseline firing in the RDL1675 strain (p = 0.035). This finding indicated that the resistance was expressed within the nervous system. Patch clamp recordings on D. melanogaster central neurons mirrored extracellular recordings where nootkatone inhibited GABA-stimulated currents by 44 ± 9% at 100 μM, whereas chloride current was inhibited 4.5-fold less at 100 μM in RDL1675. Taken together, these data suggest nootkatone toxicity in D. melanogaster is mediated through GABA receptor antagonism.
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Affiliation(s)
- Edmund J Norris
- Emerging Pathogens Institute, Entomology and Nematology Department, 2055 Mowry Road, University of Florida, Gainesville, FL 32610-0009, USA; USDA/ARS Center for Medical, Agricultural, and Veterinary Entomology, Gainesville, FL 32610-0009, USA
| | - Rui Chen
- Louisiana State University Agricultural Center, Department of Entomology, Baton Rouge, LA 70803, USA
| | - Zhilin Li
- Louisiana State University Agricultural Center, Department of Entomology, Baton Rouge, LA 70803, USA
| | - Werner Geldenhuys
- Department of Pharmaceutical Sciences, School of Pharmacy, West Virginia University, Morgantown, WV 26506, USA
| | - Jeffrey R Bloomquist
- Emerging Pathogens Institute, Entomology and Nematology Department, 2055 Mowry Road, University of Florida, Gainesville, FL 32610-0009, USA
| | - Daniel R Swale
- Louisiana State University Agricultural Center, Department of Entomology, Baton Rouge, LA 70803, USA.
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Li H, Yang Z, Liu C, Wei Y, Li J, Zhang C, Zhou J, Duan H. Novel acylpiperidine analogues as potential aphid repellent agents: Rational design, synthesis and repellent activity. J Mol Struct 2022. [DOI: 10.1016/j.molstruc.2021.132188] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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16
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Vitex negundo L. Essential Oil: Odorant Binding Protein Efficiency Using Molecular Docking Approach and Studies of the Mosquito Repellent. INSECTS 2021; 12:insects12121061. [PMID: 34940149 PMCID: PMC8703855 DOI: 10.3390/insects12121061] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 11/11/2021] [Accepted: 11/23/2021] [Indexed: 01/08/2023]
Abstract
Simple Summary Malaria fever kills millions of people annually in the tropical and subtropical countries of Africa and Asia. Because there is no effective vaccine, malaria prevention is exclusively dependent on avoiding human-vector interaction. The interaction of Vitex negundo essential oil constituents with Anopheles gambiae Odorant Binding Proteins (OBP), as well as its compositional variation, repellent efficacy, and toxicity profile, are investigated in this work. The oils were subjected to GC-MS analysis, a mosquito behavioral test, OBP-ligand interactions, Anopheles species authentication, and toxicity profile. Docking protocol validation was achieved by redocking the co-crystallized ligands and root mean square deviation (RMSD) calculation. The oil yields and compositions are climate–soil dependent with ≈71.39% monoterpenes and ≈16.32% sesquiterpene. Optimal repellency is achieved at 15 min at ED50 0.08–0.48% v/v while the RMSD was estimated to be within 0.24–1.35 Å. Strong affinities, −6.4 to −5.4 kcal/mol, were demonstrated by α-pinene, citronellal, linalool, and myrcene for OBP1, OBP7, OBP4, and OBP. respectively. The hydrophobic interactions involve Leu17, Cys35, ALA52, Leu73, Leu76, Ala88, Met91, Lys93, Trp114, Phe123, and Leu124 receptors on α-helixes 1–7 within the binding cavities, and may block the olfactory receptors resulting in disorientation. α-pinene, linalool, and myrcene are safe and suitable for use in the development of green and innovative repellents because their ligand efficiency metrics, ADME/tox, and repellency screening are all within the threshold values. Abstract (1) Background: Malaria fever affects millions of people yearly in Africa and Asia’s tropical and subtropical areas. Because there is no effective vaccine, malaria prevention is solely dependent on avoiding human-vector interaction. (2) Aim: This study examines the interaction between the constituents of Vitex negundo essential oil and Anopheles gambiae Odorant Binding Proteins (OBP) as well as the compositional variation, repellent efficacy, and toxicity profile. (3) Methods: The oils were subjected to GC-MS and mosquito behavioral analysis. OBP–ligand interactions, Anopheles species authentication, and the toxicity profile were determined by molecular docking, PCR assay and in silico ADME/tox tool. Docking protocol validation was achieved by redocking the co-crystallized ligands into the protein binding pocket and root mean square deviation (RMSD) calculation. (4) Results: The oil yields and compositions are climate–soil dependent with ≈71.39% monoterpenes and ≈16.32% sesquiterpene. Optimal repellency is achieved at 15 min at ED50 0.08–0.48% v/v while the RMSD was estimated to be within 0.24–1.35 Å. Strong affinities were demonstrated by α-pinene (−6.4 kcal/mol), citronellal (−5.5 kcal/mol), linalool (−5.4 kcal/mol), and myrcene (−5.8 kcal/mol) for OBP1, OBP7, OBP4, and OBP; respectively. The hydrophobic interactions involve Leu17 (α-helix 1), Cys35 (α-helix 2), ALA52 (α-helix 3), Leu73, Leu76 (α-helix 4), Ala88, Met91, Lys93, Trp114 (α-helix 5), Phe123 (α-helix 6), and Leu124 (α-helix 7) receptors within the binding cavities, and may cause blocking of the olfactory receptors resulting in disorientation. (5) Conclusion: The ligand efficiency metrics, ADME/tox and repellency screening are within the threshold values; hence, α-pinene, linalool, and myrcene are safe and fit-to-use in the development of a green and novel repellent.
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Chemical Composition and In Vitro Evaluation of the Mosquito (Anopheles) Repellent Property of Neem ( Azadirachta indica) Seed Oil. J Trop Med 2021; 2021:5567063. [PMID: 34194510 PMCID: PMC8203379 DOI: 10.1155/2021/5567063] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 05/26/2021] [Indexed: 11/17/2022] Open
Abstract
As one of the killer diseases in the world, malaria contributes to child mortality and global death annually. As a result, many reactive mechanisms have evolved to control and repel mosquitoes. The use of synthetic mosquito repellents with N,N-Diethyl-meta-toluamide (DEET) is one of the popular interventions despite its dermatological limitations such as skin irritations. Ethnobotanical reviews have identified that the adoption of natural repellents promises high repellence on mosquitoes with minimal side effects compared with synthetic ones. However, this has received little attention in modern pharmaceutical literature. This research is focused on the formulation of a natural mosquito repellent from the oil extracted from Azadirachta indica (A. Juss). The oil cream was formulated in concentrations of 10% v/w, 12.5% v/w, 15% v/w, 17.5% v/w, and 20% v/w using an in vitro evaluation approach. Pharmacopoeia characteristics of the cream such as pH, viscosity, spreadability, and organoleptic properties were carried out to verify acidity, permeation, and flow properties of the formulated cream. The spreadability rate was inversely proportional to the concentration of the cream in terms of oil content falling from 1.24 gm/s to 0.84 gm/s from concentrations 10% v/w to 20% v/w correspondingly. Skin irritation tests, however, indicated traces of irritation at 20% v/w. Repellency properties of the cream revealed a lasting effect on the mosquitoes, although this was dependent on concentration levels. Formulations of 17.5% v/w and 20% v/w neem seed oil cream had an equal repellency effect of 87.5%, whereas the synthetic repellent had a repellency of 75% within a justifiable time frame for all the formulations. This work shows that plant-based mosquito repellents promise a healthier approach in controlling mosquito bites, protecting the skin, and preventing malaria.
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Kelidari HR, Moemenbellah-Fard MD, Morteza-Semnani K, Amoozegar F, Shahriari-Namadi M, Saeedi M, Osanloo M. Solid-lipid nanoparticles (SLN)s containing Zataria multiflora essential oil with no-cytotoxicity and potent repellent activity against Anopheles stephensi. J Parasit Dis 2021; 45:101-108. [PMID: 33746393 DOI: 10.1007/s12639-020-01281-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Accepted: 09/22/2020] [Indexed: 01/27/2023] Open
Abstract
Malaria is still a global health concern with more than 400,000 death annually. Personal protection using mosquitoes' repellent is an effective prevention strategy, especially in endemic areas. The toxic effects of synthetics repellents and their adverse effects on fabricated goods have made the development of green repellent critical. In this study, ingredients of Zataria multiflora essential oil (ZMEO) were identified using GC-MS analysis. Solid-lipid nanoparticles containing ZMEO (1%) were prepared (SLN-ZMEO) using the high-pressure homogenizer method. The repellent activity of ZMEO and SLN-ZMEO was investigated using Klun and Debboun method and compared together. Besides, their cytotoxicity on a human skin normal cell line (HFFF2) was evaluated. Five major components of ZMEO were carvacrol (27.05%), thymol (26.452%), γ-terpinene (15.144%), o-cymene (13.584%), and α-pinene (9.483%). The SLN-ZMEO showed a spherical shape with a particle size of 134 ± 7 nm. Moreover, their polydispersity index (PDI), zeta potential and entrapment efficiency were determined as 0.24 ± 0.1, - 9.82 ± 0.95 mV and 64.6 ± 3.8%, respectively. Interestingly, the protection time of nanoformulation (93 ± 5 min) was three times longer than that of the non-formulated essential oil (29 ± 2 min). Interestingly, both samples did not show cytotoxicity on HFFF2. Therefore, the prepared nanoformulation can be used as a green and potent repellent.
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Affiliation(s)
- Hamid Reza Kelidari
- Pharmaceutical Sciences Research Center, Mazandaran University of Medical Sciences, Sari, Iran.,Student Research Committee Center, Mazandaran University of Medical Sciences, Sari, Iran
| | - Mohammad Djaefar Moemenbellah-Fard
- Research Center for Health Sciences, Department of Medical Entomology and Vector Control, School of Health, Institute of Health, Shiraz University of Medical Sciences, Shiraz, Iran
| | | | - Fatemeh Amoozegar
- Student Research Center, Fasa University of Medical Sciences, Fasa, Iran
| | - Marziae Shahriari-Namadi
- Research Center for Health Sciences, Department of Medical Entomology and Vector Control, School of Health, Institute of Health, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Majid Saeedi
- Faculty of Pharmacy, Mazandaran University of Medical Sciences, Sari, Iran
| | - Mahmoud Osanloo
- Department of Medical Nanotechnology, School of Advanced Technologies in Medicine, Fasa University of Medical Sciences, Fasa, Iran
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Pham-Thanh L, Nguyen-Tien T, Magnusson U, Bui-Nghia V, Bui-Ngoc A, Le-Thanh D, Lundkvist Å, Can-Xuan M, Nguyen-Thi Thu T, Vu-Thi Bich H, Lee HS, Nguyen-Viet H, Lindahl J. Dogs as Sentinels for Flavivirus Exposure in Urban, Peri-Urban and Rural Hanoi, Vietnam. Viruses 2021; 13:v13030507. [PMID: 33808552 PMCID: PMC8003331 DOI: 10.3390/v13030507] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 03/10/2021] [Accepted: 03/12/2021] [Indexed: 12/21/2022] Open
Abstract
Diseases caused by flaviviruses, including dengue fever and Japanese encephalitis, are major health problems in Vietnam. This cross-sectional study explored the feasibility of domestic dogs as sentinels to better understand risks of mosquito-borne diseases in Hanoi city. A total of 475 dogs serum samples from 221 households in six districts of Hanoi were analyzed by a competitive enzyme-linked immunosorbent assay (cELISA) for antibodies to the pr-E protein of West Nile virus and other flaviviruses due to cross-reactivity. The overall flavivirus seroprevalence in the dog population was 70.7% (95% CI = 66.4–74.8%). At the animal level, significant associations between seropositive dogs and district location, age, breed and keeping practice were determined. At the household level, the major risk factors were rural and peri-urban locations, presence of pigs, coil burning and households without mosquito-borne disease experience (p < 0.05). Mosquito control by using larvicides or electric traps could lower seropositivity, but other measures did not contribute to significant risk mitigation of flavivirus exposure in dogs. These results will support better control of mosquito-borne diseases in Hanoi, and they indicate that dogs can be used as sentinels for flavivirus exposure.
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Affiliation(s)
- Long Pham-Thanh
- International Livestock Research Institute (ILRI), Hanoi 10000, Vietnam; (T.N.-T.); (H.S.L.); (H.N.-V.); (J.L.)
- Department of Medical Biochemistry and Microbiology, Uppsala University, 75123 Uppsala, Sweden;
- Department of Animal Health, Ministry of Agriculture and Rural Development, Hanoi 10000, Vietnam
- Correspondence: ; Tel.: +84-934-109-999
| | - Thang Nguyen-Tien
- International Livestock Research Institute (ILRI), Hanoi 10000, Vietnam; (T.N.-T.); (H.S.L.); (H.N.-V.); (J.L.)
- Department of Medical Biochemistry and Microbiology, Uppsala University, 75123 Uppsala, Sweden;
| | - Ulf Magnusson
- Department of Clinical Sciences, Swedish University of Agricultural Sciences, 75123 Uppsala, Sweden;
| | - Vuong Bui-Nghia
- National Institute for Veterinary Research, Hanoi 10000, Vietnam; (V.B.-N.); (A.B.-N.); (D.L.-T.)
| | - Anh Bui-Ngoc
- National Institute for Veterinary Research, Hanoi 10000, Vietnam; (V.B.-N.); (A.B.-N.); (D.L.-T.)
| | - Duy Le-Thanh
- National Institute for Veterinary Research, Hanoi 10000, Vietnam; (V.B.-N.); (A.B.-N.); (D.L.-T.)
| | - Åke Lundkvist
- Department of Medical Biochemistry and Microbiology, Uppsala University, 75123 Uppsala, Sweden;
| | - Minh Can-Xuan
- Hanoi Sub-Department of Livestock Production and Animal Health, Hanoi 10000, Vietnam;
| | - Thuy Nguyen-Thi Thu
- National Institute for Hygiene and Epidemiology, Hanoi 10000, Vietnam; (T.N.-T.T.); (H.V.-T.B.)
| | - Hau Vu-Thi Bich
- National Institute for Hygiene and Epidemiology, Hanoi 10000, Vietnam; (T.N.-T.T.); (H.V.-T.B.)
| | - Hu Suk Lee
- International Livestock Research Institute (ILRI), Hanoi 10000, Vietnam; (T.N.-T.); (H.S.L.); (H.N.-V.); (J.L.)
| | - Hung Nguyen-Viet
- International Livestock Research Institute (ILRI), Hanoi 10000, Vietnam; (T.N.-T.); (H.S.L.); (H.N.-V.); (J.L.)
| | - Johanna Lindahl
- International Livestock Research Institute (ILRI), Hanoi 10000, Vietnam; (T.N.-T.); (H.S.L.); (H.N.-V.); (J.L.)
- Department of Medical Biochemistry and Microbiology, Uppsala University, 75123 Uppsala, Sweden;
- Department of Clinical Sciences, Swedish University of Agricultural Sciences, 75123 Uppsala, Sweden;
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Zakharychev VV, Kuzenkov AV, Martsynkevich AM. Good pyridine hunting: a biomimic compound, a modifier and a unique pharmacophore in agrochemicals. Chem Heterocycl Compd (N Y) 2021. [DOI: 10.1007/s10593-020-02843-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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21
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da Silva MRM, Ricci-Júnior E. An approach to natural insect repellent formulations: from basic research to technological development. Acta Trop 2020; 212:105419. [PMID: 32119826 DOI: 10.1016/j.actatropica.2020.105419] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Revised: 02/24/2020] [Accepted: 02/24/2020] [Indexed: 02/06/2023]
Abstract
The incidence of dengue, Zika, chikungunya, yellow fever and malaria cases has increased significantly in the world. To avoid mosquito bites, one of the best strategies is the use of repellents. The interest in using plants as mosquito repellents has increased significantly. In this review, has been performed a bibliographic survey of the plants with repellent activity, evaluate the trends of natural repellent formulations in the scientific literature, those described in patents and commercially available products. Limonene, 1,8-cineole, geraniol, eugenol and citronellal are the active compounds that mostly appear in the essential oils of plants with repellent activity. The type of natural repellent formulation mostly widely marketed is the spray and lotion, respectively. In patents, classic formulation as emulsion was most frequently used, followed by lotions and sprays. Data collected from scientific articles and patents show that microparticles are the most widely used extended release systems nowadays for natural repellents. The citronella essential oil was the one mostly used among the classic commercially available formulations, as well as in the extended release systems described in the literature and patents. Future research must be conducted to the use of nanotechnology in the development of extended release systems containing essential oils with repellent activity produced from natural and biodegradable materials.
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22
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Neto MFDA, Santos CBRD, Magalhães-Junior JT, Leite FHA. Identification of novel Aedes aegypti odorant-binding protein 1 modulators by ligand and structure-based approaches and bioassays. J Biomol Struct Dyn 2020; 40:117-129. [PMID: 32815781 DOI: 10.1080/07391102.2020.1808074] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Arboviruses are a group of viruses (e.g. Dengue, Chikungunya and Yellow fever virus) that are transmitted by arthropod vectors, which Aedes aegipty is the vector of main viruses in Americas. This vector is responsible to 2.4 millions of arboviruses cases in Brazil with less than a thousand deaths annually. Despite of epidemiological data, arboviruses treatment is symptomatic and the vaccine control is not effective, which makes the vector control against A. aegipty a promising strategy to diseases control. One way to achieve this goal is to development of A. aegipty sensitive olfactory modulators. Odorant binding protein 1 from A. aegypti (AaegOBP1) is essential in sensory communication, and is the first filter in odorant selection, which makes this target promising to development of new repellents. For this reason, hierarchical virtual screening (ligand-based pharmacophore model and molecular docking) together volatility filter was applied at Sigma-Aldrich database (n = 126.851) to prioritize potential molecules to repellency assays. Three compounds showed adequate stereo-electronic requirements (QFIT> 81.53), score to AaegOBP1 binding site (Score > 36.0) and volatile properties and it was chosen for repellency assays. ZINC00170981 and ZINC00131924 showed a dose-response behavior, while ZINC01621824 did not showed activity in repellency assays. Finally, Molecular Dynamics (MD) was employed to hypothesize the stability of protein-ligand complexes. According to RMSD, RMSF and binding free energy data, ZINC00170981 and ZINC00131924 were able to stabilize AaegOBP1 binding-site during the trajectory by interactions with key residues such as His77, Leu89 and Trp114). Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
| | - Cleydson Breno Rodrigues Dos Santos
- Laboratório de Modelagem e Química Computacional, Departamento de Ciências Biológicas e da Saúde, Universidade Federal do Amapá, Macapá, Brasil
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23
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Wooding M, Rohwer ER, Naudé Y. Chemical profiling of the human skin surface for malaria vector control via a non-invasive sorptive sampler with GC×GC-TOFMS. Anal Bioanal Chem 2020; 412:5759-5777. [PMID: 32681223 DOI: 10.1007/s00216-020-02799-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Revised: 06/26/2020] [Accepted: 07/01/2020] [Indexed: 12/28/2022]
Abstract
Volatile organic compounds (VOCs) and semi-VOCs detected on the human skin surface are of great interest to researchers in the fields of metabolomics, diagnostics, and skin microbiota and in the study of anthropophilic vector mosquitoes. Mosquitoes use chemical cues to find their host, and humans can be ranked for attractiveness to mosquitoes based on their skin chemical profile. Additionally, mosquitoes show a preference to bite certain regions on the human host. In this study, the chemical differences in the skin surface profiles of 20 human volunteers were compared based on inter-human attractiveness to mosquitoes, as well as inter- and intra-human mosquito biting site preference. A passive, non-invasive approach was followed to sample the wrist and ankle skin surface region. An in-house developed polydimethylsiloxane (PDMS) passive sampler was used to concentrate skin VOCs and semi-VOCs prior to thermal desorption directly in the GC inlet with comprehensive gas chromatography coupled to time-of-flight mass spectrometry (GC×GC-TOFMS). Compounds from a broad range of chemical classes were detected and identified as contributing to the differences in the surface skin chemical profiles. 5-Ethyl-1,2,3,4-tetrahydronaphthalene, 1,1'-oxybisoctane, 2-(dodecyloxy)ethanol, α,α-dimethylbenzene methanol, methyl salicylate, 2,6,10,14-tetramethylhexadecane, 1,2-benzenedicarboxylic acid, bis(2-methylpropyl) ester, 4-methylbenzaldehyde, 2,6-diisopropylnaphthalene, n-hexadecanoic acid, and γ-oxobenzenebutanoic acid ethyl ester were closely associated with individuals who perceived themselves as attractive for mosquitoes. Additionally, biological lead compounds as potential attractants or repellants in vector control strategies were tentatively identified. Results augment current knowledge on human skin chemical profiles and show the potential of using a non-invasive sampling approach to investigate anthropophilic mosquito-host interactions. Graphical abstract.
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Affiliation(s)
- Madelien Wooding
- Department of Chemistry, University of Pretoria, Private Bag X20, Hatfield, Pretoria, 0028, South Africa
| | - Egmont R Rohwer
- Department of Chemistry, University of Pretoria, Private Bag X20, Hatfield, Pretoria, 0028, South Africa
| | - Yvette Naudé
- Department of Chemistry, University of Pretoria, Private Bag X20, Hatfield, Pretoria, 0028, South Africa.
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Portilla-Pulido JS, Castillo-Morales RM, Barón-Rodríguez MA, Duque JE, Mendez-Sanchez SC. Design of a Repellent Against Aedes aegypti (Diptera: Culicidae) Using in silico Simulations With AaegOBP1 Protein. JOURNAL OF MEDICAL ENTOMOLOGY 2020; 57:463-476. [PMID: 31670811 PMCID: PMC7530563 DOI: 10.1093/jme/tjz171] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Indexed: 06/10/2023]
Abstract
Skin irritation has been reported to be the main adverse effect of excessive use of N,N-diethyl-m-toluamide (DEET) and ethyl 3-acetyl(butyl)amino (IR3535) commercial repellents. Therefore, there is an interest in alternatives of natural origin such as essential oils (EOs) and major compounds, which have repellent effects but have no contraindications. The main purpose of the present study was to identify the repellent effect of selected terpenes on Aedes aegypti Linnaeus, 1762 (Diptera: Culicidae) by in silico analysis based on their affinity with the odorant protein AaegOBP1. The protein-metabolite interactions in 20 terpenes were analyzed using the SwissDock tool. Terpenes presenting the highest affinity compared with commercial repellents were selected to evaluate repellent activity at concentrations 0.1, 10, and 25% against Ae. aegypti. Different periods (0-2, 2-15, 15-60 min) were evaluated with DEET as a positive control. The toxicity of terpenes was verified through Osiris and Molinspiration Cheminformatics Software, and cytotoxicity assays in Vero and HepaRG cells were performed using the MTT method. Two formulations were prepared with polyethylene glycol to evaluate skin long-lasting in vivo assay. The results showed four terpenes: geranyl acetate, nerolidol, α-bisabolol, and nerol, with affinity to AaegOBP1 comparable with DEET and IR3535. Geranyl acetate, nerolidol, and their mixtures showed no cytotoxicity and protection percentages close to 100% during the test at concentrations 10 and 25%. Long-lasting assays with geranyl acetate and nerolidol formulate showed 3 h as maximum protection time with 100% protection percentage. These metabolites and their mixtures are candidates to repellent formulations with times and protection percentages similar to DEET.
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Affiliation(s)
- Johan Sebastián Portilla-Pulido
- Grupo de Investigación en Bioquímica y Microbiología (GIBIM). Escuela de Química, Universidad Industrial de Santander, Bucaramanga A.A., Colombia
- Centro de Investigaciones en Enfermedades Tropicales - CINTROP. Facultad de Salud. Escuela de Medicina, Departamento de Ciencias Básicas, Universidad Industrial de Santander, Guatiguará Technology and Research Park, Piedecuesta, Santander, Colombia
| | - Ruth Mariela Castillo-Morales
- Centro de Investigaciones en Enfermedades Tropicales - CINTROP. Facultad de Salud. Escuela de Medicina, Departamento de Ciencias Básicas, Universidad Industrial de Santander, Guatiguará Technology and Research Park, Piedecuesta, Santander, Colombia
| | | | - Jonny Edward Duque
- Centro de Investigaciones en Enfermedades Tropicales - CINTROP. Facultad de Salud. Escuela de Medicina, Departamento de Ciencias Básicas, Universidad Industrial de Santander, Guatiguará Technology and Research Park, Piedecuesta, Santander, Colombia
| | - Stelia Carolina Mendez-Sanchez
- Grupo de Investigación en Bioquímica y Microbiología (GIBIM). Escuela de Química, Universidad Industrial de Santander, Bucaramanga A.A., Colombia
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25
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Wooding M, Naudé Y, Rohwer E, Bouwer M. Controlling mosquitoes with semiochemicals: a review. Parasit Vectors 2020; 13:80. [PMID: 32066499 PMCID: PMC7027039 DOI: 10.1186/s13071-020-3960-3] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2019] [Accepted: 02/11/2020] [Indexed: 12/20/2022] Open
Abstract
The use of semiochemicals in odour-based traps for surveillance and control of vector mosquitoes is deemed a new and viable component for integrated vector management programmes. Over 114 semiochemicals have been identified, yet implementation of these for management of infectious diseases such as malaria, dengue, chikungunya and Rift Valley fever is still a major challenge. The difficulties arise due to variation in how different mosquito species respond to not only single chemical compounds but also complex chemical blends. Additionally, mosquitoes respond to different volatile blends when they are looking for a mating partner, oviposition sites or a meal. Analytically the challenge lies not only in correctly identifying these semiochemical signals and cues but also in developing formulations that effectively mimic blend ratios that different mosquito species respond to. Only then can the formulations be used to enhance the selectivity and efficacy of odour-based traps. Understanding how mosquitoes use semiochemical cues and signals to survive may be key to unravelling these complex interactions. An overview of the current studies of these chemical messages and the chemical ecology involved in complex behavioural patterns is given. This includes an updated list of the semiochemicals which can be used for integrated vector control management programmes. A thorough understanding of these semiochemical cues is of importance for the development of new vector control methods that can be integrated into established control strategies.![]()
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Affiliation(s)
- Madelien Wooding
- Department of Chemistry, University of Pretoria, Hatfield, Pretoria, South Africa
| | - Yvette Naudé
- Department of Chemistry, University of Pretoria, Hatfield, Pretoria, South Africa
| | - Egmont Rohwer
- Department of Chemistry, University of Pretoria, Hatfield, Pretoria, South Africa
| | - Marc Bouwer
- Forestry and Agricultural Biotechnology Institute, University of Pretoria, Hatfield, Pretoria, South Africa.
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26
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da Costa KS, Galúcio JM, da Costa CHS, Santana AR, dos Santos Carvalho V, do Nascimento LD, Lima e Lima AH, Neves Cruz J, Alves CN, Lameira J. Exploring the Potentiality of Natural Products from Essential Oils as Inhibitors of Odorant-Binding Proteins: A Structure- and Ligand-Based Virtual Screening Approach To Find Novel Mosquito Repellents. ACS OMEGA 2019; 4:22475-22486. [PMID: 31909330 PMCID: PMC6941369 DOI: 10.1021/acsomega.9b03157] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Accepted: 11/29/2019] [Indexed: 05/31/2023]
Abstract
Odorant-binding proteins (OBPs) are the main olfactory proteins of mosquitoes, and their structures have been widely explored to develop new repellents. In the present study, we combined ligand- and structure-based virtual screening approaches using as a starting point 1633 compounds from 71 botanical families obtained from the Essential Oil Database (EssOilDB). Using as reference the crystallographic structure of N,N-diethyl-meta-toluamide interacting with the OBP1 homodimer of Anopheles gambiae (AgamOBP1), we performed a structural and pharmacophoric similarity search to select potential natural products from the library. Thymol acetate, 4-(4-methyl phenyl)-pentanal, thymyl isovalerate, and p-cymen-8-yl demonstrated a favorable chemical correlation with DEET and also had high-affinity interactions with the OBP binding pocket that molecular dynamics simulations showed to be stable. To the best of our knowledge, this is the first study to evaluate on a large scale the potentiality of NPs from essential oils as inhibitors of the mosquito OBP1 using in silico approaches. Our results could facilitate the design of novel repellents with improved selectivity and affinity to the protein binding pocket and can shed light on the mechanism of action of these compounds against insect olfactory recognition.
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Affiliation(s)
- Kauȇ Santana da Costa
- Institute
of Biodiversity, Federal University of Western
Pará, 68035-110 Santarém, Pará, Brazil
| | - João Marcos Galúcio
- Institute
of Biodiversity, Federal University of Western
Pará, 68035-110 Santarém, Pará, Brazil
| | | | - Amanda Ruslana Santana
- Department
of Pharmaceutical Sciences, Federal University
of Pará, 66060-902 Belém, Pará, Brazil
| | - Vitor dos Santos Carvalho
- Institute of Exact and Natural
Sciences and Institute of Biological Sciences, Federal
University of Pará, 66075-110 Belém, Pará, Brazil
| | | | - Anderson Henrique Lima e Lima
- Institute of Exact and Natural
Sciences and Institute of Biological Sciences, Federal
University of Pará, 66075-110 Belém, Pará, Brazil
| | - Jorddy Neves Cruz
- Department
of Pharmaceutical Sciences, Federal University
of Pará, 66060-902 Belém, Pará, Brazil
| | - Claudio Nahum Alves
- Institute of Exact and Natural
Sciences and Institute of Biological Sciences, Federal
University of Pará, 66075-110 Belém, Pará, Brazil
| | - Jerônimo Lameira
- Institute of Exact and Natural
Sciences and Institute of Biological Sciences, Federal
University of Pará, 66075-110 Belém, Pará, Brazil
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27
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Zhu JJ, Cermak SC, Kenar JA, Brewer G, Haynes KF, Boxler D, Baker PD, Wang D, Wang C, Li AY, Xue RD, Shen Y, Wang F, Agramonte NM, Bernier UR, de Oliveira Filho JG, Borges LMF, Friesen K, Taylor DB. Better than DEET Repellent Compounds Derived from Coconut Oil. Sci Rep 2018; 8:14053. [PMID: 30232355 PMCID: PMC6145915 DOI: 10.1038/s41598-018-32373-7] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Accepted: 09/06/2018] [Indexed: 11/09/2022] Open
Abstract
Hematophagous arthropods are capable of transmitting human and animal pathogens worldwide. Vector-borne diseases account for 17% of all infectious diseases resulting in 700,000 human deaths annually. Repellents are a primary tool for reducing the impact of biting arthropods on humans and animals. N,N-Diethyl-meta-toluamide (DEET), the most effective and long-lasting repellent currently available commercially, has long been considered the gold standard in insect repellents, but with reported human health issues, particularly for infants and pregnant women. In the present study, we report fatty acids derived from coconut oil which are novel, inexpensive and highly efficacious repellant compounds. These coconut fatty acids are active against a broad array of blood-sucking arthropods including biting flies, ticks, bed bugs and mosquitoes. The medium-chain length fatty acids from C8:0 to C12:0 were found to exhibit the predominant repellent activity. In laboratory bioassays, these fatty acids repelled biting flies and bed bugs for two weeks after application, and ticks for one week. Repellency was stronger and with longer residual activity than that of DEET. In addition, repellency was also found against mosquitoes. An aqueous starch-based formulation containing natural coconut fatty acids was also prepared and shown to protect pastured cattle from biting flies up to 96-hours in the hot summer, which, to our knowledge, is the longest protection provided by a natural repellent product studied to date.
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Affiliation(s)
- Junwei J Zhu
- U.S. Department of Agriculture, Agricultural Research Service, Agroecosystem Management Research Unit, University of Nebraska, Lincoln, Nebraska, 68583, USA.
| | - Steven C Cermak
- U.S. Department of Agriculture, Agricultural Research Service, National Center for Agricultural Utilization Research, Peoria, Illinois, 61604, USA
| | - James A Kenar
- U.S. Department of Agriculture, Agricultural Research Service, National Center for Agricultural Utilization Research, Peoria, Illinois, 61604, USA
| | - Gary Brewer
- Department of Entomology, University of Nebraska, Lincoln, Nebraska, 68583, USA
| | - Kenneth F Haynes
- Department of Entomology, University of Kentucky, Lexington, 40546, USA
| | - Dave Boxler
- Department of Entomology, University of Nebraska, Lincoln, Nebraska, 68583, USA
| | - Paul D Baker
- Department of Entomology, University of Kentucky, Lexington, 40546, USA
| | - Desen Wang
- Key Laboratory of Bio-Pesticide Innovation and Application of Guangdong Province, Department of Entomology, College of Agriculture, South China Agricultural University, Guangzhou, 510642, Guangdong Province, China
| | - Changlu Wang
- Department of Entomology, Rutgers University, New Brunswick, 08901, USA
| | - Andrew Y Li
- U.S. Department of Agriculture, Agricultural Research Service, Invasive Insect Biocontrol and Behavior Laboratory, Beltsville Agricultural Research Center-West, Beltsville, Maryland, 20705, USA
| | - Rui-de Xue
- Anastasia Mosquito Control District, 120 EOC Drive, St. Augustine, Florida, 32092, USA
| | - Yuan Shen
- Anastasia Mosquito Control District, 120 EOC Drive, St. Augustine, Florida, 32092, USA
| | - Fei Wang
- Anastasia Mosquito Control District, 120 EOC Drive, St. Augustine, Florida, 32092, USA
| | - Natasha M Agramonte
- U.S. Department of Agriculture, Agricultural Research Service, Center for Medical, Agricultural and Veterinary Entomology, Gainesville, Florida, 32608, USA
| | - Ulrich R Bernier
- U.S. Department of Agriculture, Agricultural Research Service, Center for Medical, Agricultural and Veterinary Entomology, Gainesville, Florida, 32608, USA
| | - Jaires G de Oliveira Filho
- Departamento de Microbiologia, Imunologia, Parasitologia e Patologia, Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás - UFG, Goiânia, GO, Brazil
| | - Ligia M F Borges
- Departamento de Microbiologia, Imunologia, Parasitologia e Patologia, Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás - UFG, Goiânia, GO, Brazil
| | - Kristina Friesen
- U.S. Department of Agriculture, Agricultural Research Service, Agroecosystem Management Research Unit, University of Nebraska, Lincoln, Nebraska, 68583, USA
| | - David B Taylor
- U.S. Department of Agriculture, Agricultural Research Service, Agroecosystem Management Research Unit, University of Nebraska, Lincoln, Nebraska, 68583, USA
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28
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Film bulk acoustic resonators (FBARs) as biosensors: A review. Biosens Bioelectron 2018; 116:1-15. [DOI: 10.1016/j.bios.2018.05.028] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Revised: 05/08/2018] [Accepted: 05/16/2018] [Indexed: 01/01/2023]
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29
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Thireou T, Kythreoti G, Tsitsanou KE, Koussis K, Drakou CE, Kinnersley J, Kröber T, Guerin PM, Zhou JJ, Iatrou K, Eliopoulos E, Zographos SE. Identification of novel bioinspired synthetic mosquito repellents by combined ligand-based screening and OBP-structure-based molecular docking. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2018; 98:48-61. [PMID: 29751047 DOI: 10.1016/j.ibmb.2018.05.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Revised: 04/30/2018] [Accepted: 05/07/2018] [Indexed: 05/24/2023]
Abstract
In this work we report a fast and efficient virtual screening protocol for discovery of novel bioinspired synthetic mosquito repellents with lower volatility and, in all likelihood, increased protection time as compared with their plant-derived parental compounds. Our screening protocol comprises two filtering steps. The first filter is based on the shape and chemical similarity to known plant-derived repellents, whereas the second filter is based on the predicted similarity of the ligand's binding mode to the Anopheles gambiae odorant binding protein (AgamOBP1) relative to that of DEET and Icaridin to the same OBP. Using this protocol, a chemical library containing 42,755 synthetic molecules was screened in silico and sixteen selected compounds were tested for their affinity to AgamOBP1 in vitro and repellence against A. gambiae female mosquitoes using a warm-body repellent assay. One of them showed DEET-like repellence (91%) but with significantly lower volatility (2.84 × 10-6 mmHg) than either DEET (1.35 × 10-3 mmHg) or its parental cuminic acid (3.08 × 10-3 mmHg), and four other compounds were found to exhibit repellent indices between 69 and 79%. Overall, a correlation was not evident between repellence and OBP-binding strength. In contrast, a correlation between binding mode and repellence was found.
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Affiliation(s)
- Trias Thireou
- Department of Biotechnology, Agricultural University of Athens, Iera Odos 75, 11855 Athens, Greece
| | - Georgia Kythreoti
- Insect Molecular Genetics and Biotechnology Group, Institute of Biosciences & Applications, National Centre for Scientific Research "Demokritos", 153 10 Aghia Paraskevi, Athens, Greece
| | - Katerina E Tsitsanou
- Institute of Biology, Medicinal Chemistry & Biotechnology, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 11635 Athens, Greece
| | - Konstantinos Koussis
- Insect Molecular Genetics and Biotechnology Group, Institute of Biosciences & Applications, National Centre for Scientific Research "Demokritos", 153 10 Aghia Paraskevi, Athens, Greece
| | - Christina E Drakou
- Institute of Biology, Medicinal Chemistry & Biotechnology, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 11635 Athens, Greece
| | - Julie Kinnersley
- Department of Biological Chemistry and Crop Protection, Rothamsted Research, Harpenden, AL5 2JQ, UK
| | - Thomas Kröber
- Institute of Biology, Faculty of Science, University of Neuchâtel, rue Emile-Argand, 11, 2000 Neuchâtel, Switzerland
| | - Patrick M Guerin
- Institute of Biology, Faculty of Science, University of Neuchâtel, rue Emile-Argand, 11, 2000 Neuchâtel, Switzerland
| | - Jing-Jiang Zhou
- Department of Biological Chemistry and Crop Protection, Rothamsted Research, Harpenden, AL5 2JQ, UK
| | - Kostas Iatrou
- Insect Molecular Genetics and Biotechnology Group, Institute of Biosciences & Applications, National Centre for Scientific Research "Demokritos", 153 10 Aghia Paraskevi, Athens, Greece
| | - Elias Eliopoulos
- Department of Biotechnology, Agricultural University of Athens, Iera Odos 75, 11855 Athens, Greece
| | - Spyros E Zographos
- Institute of Biology, Medicinal Chemistry & Biotechnology, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 11635 Athens, Greece.
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30
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Kröber T, Koussis K, Bourquin M, Tsitoura P, Konstantopoulou M, Awolola TS, Dani FR, Qiao H, Pelosi P, Iatrou K, Guerin PM. Odorant-binding protein-based identification of natural spatial repellents for the African malaria mosquito Anopheles gambiae. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2018; 96:36-50. [PMID: 29656020 DOI: 10.1016/j.ibmb.2018.03.008] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Revised: 02/22/2018] [Accepted: 03/29/2018] [Indexed: 06/08/2023]
Abstract
There is increasing interest in the development of effective mosquito repellents of natural origin to reduce transmission of diseases such as malaria and yellow fever. To achieve this we have employed an in vitro competition assay involving odorant-binding proteins (OBPs) of the malaria mosquito, Anopheles gambiae, with a predominantly female expression bias to identify plant essential oils (EOs) containing bioactive compounds that target mosquito olfactory function. EOs and their fractions capable of binding to such OBPs displayed repellence against female mosquitoes in a laboratory repellent assay. Repellent EOs were subjected to gas chromatographic analysis linked to antennogram (EAG) recordings from female A. gambiae to identify the biologically active constituents. Among these compounds cumin alcohol, carvacrol, ethyl cinnamate and butyl cinnamate proved as effective as DEET at an equivalent dose in the repellent assay, and combinations of carvacrol with either butyl cinnamate or cumin alcohol proved to be significantly more effective than DEET in the assay. When tested as spatial repellents in experimental shelters housing sleeping humans in northern Nigeria a binary mixture of carvacrol plus cumin alcohol caused mosquitoes to leave shelters in significantly higher numbers to those induced by DEET in female Anopheles spp. and in numbers equivalent to that of DEET in Culex spp. mosquitoes. These findings indicate an approach for the identification of biologically active molecules of natural origin serving as repellents for mosquitoes.
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Affiliation(s)
- Thomas Kröber
- Institute of Biology, Faculty of Science, University of Neuchâtel, rue Emile-Argand 11, 2000 Neuchâtel, Switzerland.
| | - Konstantinos Koussis
- Insect Molecular Genetics and Biotechnology Group, National Centre for Scientific Research "Demokritos", 153 10 Aghia Paraskevi, Athens, Greece.
| | - Martine Bourquin
- Institute of Biology, Faculty of Science, University of Neuchâtel, rue Emile-Argand 11, 2000 Neuchâtel, Switzerland.
| | - Panagiota Tsitoura
- Insect Molecular Genetics and Biotechnology Group, National Centre for Scientific Research "Demokritos", 153 10 Aghia Paraskevi, Athens, Greece.
| | - Maria Konstantopoulou
- Laboratory of Chemical Ecology and Natural Products, Institute of Biosciences & Applications, National Centre for Scientific Research "Demokritos", 153 10 Aghia Paraskevi, Athens, Greece.
| | | | | | - Huili Qiao
- Department of Agriculture, Food and Environment, University of Pisa, Pisa, Italy.
| | - Paolo Pelosi
- Department of Agriculture, Food and Environment, University of Pisa, Pisa, Italy.
| | - Kostas Iatrou
- Insect Molecular Genetics and Biotechnology Group, National Centre for Scientific Research "Demokritos", 153 10 Aghia Paraskevi, Athens, Greece.
| | - Patrick M Guerin
- Institute of Biology, Faculty of Science, University of Neuchâtel, rue Emile-Argand 11, 2000 Neuchâtel, Switzerland.
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31
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Muema JM, Bargul JL, Njeru SN, Onyango JO, Imbahale SS. Prospects for malaria control through manipulation of mosquito larval habitats and olfactory-mediated behavioural responses using plant-derived compounds. Parasit Vectors 2017; 10:184. [PMID: 28412962 PMCID: PMC5392979 DOI: 10.1186/s13071-017-2122-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Accepted: 03/29/2017] [Indexed: 11/14/2022] Open
Abstract
Malaria presents an overwhelming public health challenge, particularly in sub-Saharan Africa where vector favourable conditions and poverty prevail, potentiating the disease burden. Behavioural variability of malaria vectors poses a great challenge to existing vector control programmes with insecticide resistance already acquired to nearly all available chemical compounds. Thus, approaches incorporating plant-derived compounds to manipulate semiochemical-mediated behaviours through disruption of mosquito olfactory sensory system have considerably gained interests to interrupt malaria transmission cycle. The combination of push-pull methods and larval control have the potential to reduce malaria vector populations, thus minimising the risk of contracting malaria especially in resource-constrained communities where access to synthetic insecticides is a challenge. In this review, we have compiled information regarding the current status of knowledge on manipulation of larval ecology and chemical-mediated behaviour of adult mosquitoes with plant-derived compounds for controlling mosquito populations. Further, an update on the current advancements in technologies to improve longevity and efficiency of these compounds for field applications has been provided.
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Affiliation(s)
- Jackson M Muema
- Department of Biochemistry, Jomo Kenyatta University of Agriculture and Technology, P.O. Box 62000-00200, Nairobi, Kenya.
| | - Joel L Bargul
- Department of Biochemistry, Jomo Kenyatta University of Agriculture and Technology, P.O. Box 62000-00200, Nairobi, Kenya.,Molecular Biology and Bioinformatics Unit, International Centre of Insect Physiology and Ecology, P.O. Box 30772-00100, Nairobi, Kenya
| | - Sospeter N Njeru
- Department of Medicine, Faculty of Health Sciences, Kisii University, P.O. Box 408-40200, Kisii, Kenya.,Present Address: Fritz Lipmann Institute (FLI) - Leibniz Institute of Aging Research, D-07745, Jena, Germany
| | - Joab O Onyango
- Department of Chemical Science and Technology, Technical University of Kenya, P.O. Box 52428-00200, Nairobi, Kenya
| | - Susan S Imbahale
- Department of Applied and Technical Biology, Technical University of Kenya, P.O. Box 52428-00200, Nairobi, Kenya
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Norris EJ, Coats JR. Current and Future Repellent Technologies: The Potential of Spatial Repellents and Their Place in Mosquito-Borne Disease Control. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2017; 14:ijerph14020124. [PMID: 28146066 PMCID: PMC5334678 DOI: 10.3390/ijerph14020124] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Revised: 01/19/2017] [Accepted: 01/22/2017] [Indexed: 12/31/2022]
Abstract
Every year, approximately 700,000 people die from complications associated with etiologic disease agents transmitted by mosquitoes. While insecticide-based vector control strategies are important for the management of mosquito-borne diseases, insecticide-resistance and other logistical hurdles may lower the efficacy of this approach, especially in developing countries. Repellent technologies represent another fundamental aspect of preventing mosquito-borne disease transmission. Among these technologies, spatial repellents are promising alternatives to the currently utilized contact repellents and may significantly aid in the prevention of mosquito-borne disease if properly incorporated into integrated pest management approaches. As their deployment would not rely on prohibitively expensive or impractical novel accessory technologies and resources, they have potential utility in developing countries where the burden of mosquito-borne disease is most prevalent. This review aims to describe the history of various repellent technologies, highlight the potential of repellent technologies in preventing the spread of mosquito-borne disease, and discuss currently known mechanisms that confer resistance to current contact and spatial repellents, which may lead to the failures of these repellents. In the subsequent section, current and future research projects aimed at exploring long-lasting non-pyrethroid spatial repellent molecules along with new paradigms and rationale for their development will be discussed.
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Affiliation(s)
- Edmund J Norris
- Department of Entomology, Iowa State University, Ames, IA 50011, USA.
| | - Joel R Coats
- Department of Entomology, Iowa State University, Ames, IA 50011, USA.
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Drakou CE, Tsitsanou KE, Potamitis C, Fessas D, Zervou M, Zographos SE. The crystal structure of the AgamOBP1•Icaridin complex reveals alternative binding modes and stereo-selective repellent recognition. Cell Mol Life Sci 2017; 74:319-338. [PMID: 27535661 PMCID: PMC11107575 DOI: 10.1007/s00018-016-2335-6] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Revised: 07/27/2016] [Accepted: 08/09/2016] [Indexed: 10/21/2022]
Abstract
Anopheles gambiae Odorant Binding Protein 1 in complex with the most widely used insect repellent DEET, was the first reported crystal structure of an olfactory macromolecule with a repellent, and paved the way for OBP1-structure-based approaches for discovery of new host-seeking disruptors. In this work, we performed STD-NMR experiments to directly monitor and verify the formation of a complex between AgamOBP1 and Icaridin, an efficient DEET alternative. Furthermore, Isothermal Titration Calorimetry experiments provided evidence for two Icaridin-binding sites with different affinities (Kd = 0.034 and 0.714 mM) and thermodynamic profiles of ligand binding. To elucidate the binding mode of Icaridin, the crystal structure of AgamOBP1•Icaridin complex was determined at 1.75 Å resolution. We found that Icaridin binds to the DEET-binding site in two distinct orientations and also to a novel binding site located at the C-terminal region. Importantly, only the most active 1R,2S-isomer of Icaridin's equimolar diastereoisomeric mixture binds to the AgamOBP1 crystal, providing structural evidence for the possible contribution of OBP1 to the stereoselectivity of Icaridin perception in mosquitoes. Structural analysis revealed two ensembles of conformations differing mainly in spatial arrangement of their sec-butyl moieties. Moreover, structural comparison with DEET indicates a common recognition mechanism for these structurally related repellents. Ligand interactions with both sites and binding modes were further confirmed by 2D 1H-15N HSQC NMR spectroscopy. The identification of a novel repellent-binding site in AgamOBP1 and the observed structural conservation and stereoselectivity of its DEET/Icaridin-binding sites open new perspectives for the OBP1-structure-based discovery of next-generation insect repellents.
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Affiliation(s)
- Christina E Drakou
- Institute of Biology, Medicinal Chemistry and Biotechnology, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 11635, Athens, Greece
| | - Katerina E Tsitsanou
- Institute of Biology, Medicinal Chemistry and Biotechnology, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 11635, Athens, Greece
| | - Constantinos Potamitis
- Institute of Biology, Medicinal Chemistry and Biotechnology, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 11635, Athens, Greece
| | - Dimitrios Fessas
- Department of Food, Environmental and Nutritional Sciences (DeFENS), Università degli Studi di Milano, Via Celoria 2, 20133, Milan, Italy
| | - Maria Zervou
- Institute of Biology, Medicinal Chemistry and Biotechnology, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 11635, Athens, Greece
| | - Spyros E Zographos
- Institute of Biology, Medicinal Chemistry and Biotechnology, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 11635, Athens, Greece.
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Patterson GM. Looking Backward, Looking Forward: The Long, Torturous Struggle with Mosquitoes. INSECTS 2016; 7:E56. [PMID: 27775554 PMCID: PMC5198204 DOI: 10.3390/insects7040056] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Revised: 10/02/2016] [Accepted: 10/05/2016] [Indexed: 01/07/2023]
Abstract
The American anti-mosquito movement grew out of the discovery of the role of mosquitoes in transferring pathogens and public concern about pest and nuisance mosquitoes in the late 1800s. In the 20th century, organized mosquito control in the United States passed through three eras: mechanical, chemical, and integrated mosquito control. Mosquito control in the 21st century faces the challenge of emerging pathogens, invasive mosquito species, and balancing concerns about the environment with effective control strategies.
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Affiliation(s)
- Gordon M Patterson
- Florida Institute of Technology, 150 W. University Blvd., Melbourne, FL 32901, USA.
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Sugiharto VA, Grieco JP, Murphy JR, Olsen CH, Colacicco-Mayhugh MG, Stewart VA, Achee NL, Turell MJ. Effects of Preexposure to DEET on the Downstream Blood-Feeding Behaviors of Aedes aegypti (Diptera: Culicidae) Mosquitoes. JOURNAL OF MEDICAL ENTOMOLOGY 2016; 53:1100-1104. [PMID: 27288690 DOI: 10.1093/jme/tjw066] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Accepted: 04/11/2016] [Indexed: 06/06/2023]
Abstract
Mosquito behavior is heavily influenced by the chemical molecules in the environment. This knowledge can be used to modify insect behaviors; particularly to reduce vector-host contact as a powerful method for disease prevention. N,N-Diethyl-meta-toluamide (DEET) is the most widely used insect repellent in the market and an excellent example of a chemical that has been used to modify insect behavior for disease prevention. However, genetic insensitivity and habituation in Aedes aegypti (L.) mosquitoes after preexposure to DEET have been reported. In this study, we investigated the effect of preexposure to DEET on the downstream blood-feeding behavior of Ae. aegypti mosquitoes and the duration of the effect. We exposed mosquitoes to four different DEET concentrations: 0.10, 0.12, 0.14, and 0.16% for 10 min then allowed the mosquitoes to blood-feed on an artificial blood-feeding system either immediately or after being held for 1, 3, 6, or 24 h following DEET exposure. We found that preexposing Ae. aegypti mosquitoes to 0.14 or 0.16% DEET lowered their blood engorgement level, but did not alter their landing and probing behavior when compared to the control test populations. The reduction in complete blood-feeding was observed at all time periods tested, but was only statistically significant at 3 and 6 h after the preexposure process. Because reduction in blood meal has been associated with increased refeeding, future studies analyzing the effect of this behavior using arbovirus-infected mosquitoes are needed to address the concern of potentially increased vectorial capacity.
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Affiliation(s)
- Victor A Sugiharto
- Department of Preventive Medicine & Biostatistics, Uniformed Services University of the Health Sciences, Bethesda, MD 20814 (; ; ; ; ; )
| | - John P Grieco
- Department of Preventive Medicine & Biostatistics, Uniformed Services University of the Health Sciences, Bethesda, MD 20814 (; ; ; ; ; )
- Current Address: Department of Biological Sciences, Eck Institute for Global Health, University of Notre Dame, 239 Galvin Life Science Center, Notre Dame, IN 46556
| | - Jittawadee R Murphy
- Department of Preventive Medicine & Biostatistics, Uniformed Services University of the Health Sciences, Bethesda, MD 20814 (; ; ; ; ; )
| | - Cara H Olsen
- Department of Preventive Medicine & Biostatistics, Uniformed Services University of the Health Sciences, Bethesda, MD 20814 (; ; ; ; ; )
| | | | - V Ann Stewart
- Department of Preventive Medicine & Biostatistics, Uniformed Services University of the Health Sciences, Bethesda, MD 20814 (; ; ; ; ; )
| | - Nicole L Achee
- Department of Preventive Medicine & Biostatistics, Uniformed Services University of the Health Sciences, Bethesda, MD 20814 (; ; ; ; ; )
- Current Address: Department of Biological Sciences, Eck Institute for Global Health, University of Notre Dame, 239 Galvin Life Science Center, Notre Dame, IN 46556
| | - Michael J Turell
- Department of Vector Assessment, Virology Division, US Army Medical Research Institute of Infectious Diseases, Fort Detrick, MD 21702
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Sathantriphop S, Achee NL, Sanguanpong U, Chareonviriyaphap T. The effects of plant essential oils on escape response and mortality rate of Aedes aegypti and Anopheles minimus. JOURNAL OF VECTOR ECOLOGY : JOURNAL OF THE SOCIETY FOR VECTOR ECOLOGY 2015; 40:318-326. [PMID: 26611967 DOI: 10.1111/jvec.12170] [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: 03/20/2015] [Accepted: 05/26/2015] [Indexed: 06/05/2023]
Abstract
The High Throughput Screening System (HITSS) has been applied in insecticide behavioral response studies with various mosquito species. In general, chemical or natural compounds can produce a range of insect responses: contact irritancy, spatial repellency, knock-down, and toxicity. This study characterized these actions in essential oils derived from citronella, hairy basil, catnip, and vetiver in comparison to DEET and picaridin against Aedes aegypti and Anopheles minimus mosquito populations. Results indicated the two mosquito species exhibited significantly different (P<0.05) contact irritant escape responses between treatment and control for all tested compound concentrations, except with the minimum dose of picaridin (P>0.05) against Ae. aegypti. Spatial repellency responses were elicited in both mosquito species when exposed to all compounds, but the strength of the repellent response was dependent on compound and concentration. Data show that higher test concentrations had greatest toxic effects on both mosquito populations, but vetiver had no toxic effect on Ae. aegypti and picaridin did not elicit toxicity in either Ae. aegypti or An. minimus at any test concentration. Ultimately, this study demonstrates the ability of the HITSS assay to guide selection of effective plant essential oils for repelling, irritating, and killing mosquitoes.
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Affiliation(s)
- Sunaiyana Sathantriphop
- Department of Entomology, Faculty of Agriculture, Kasetsart University, Bangkok 10900, Thailand
| | - Nicole L Achee
- Eck Institute for Global Health, Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556, U.S.A
| | - Unchalee Sanguanpong
- Institute of Research and Development, Rajamangala University of Technology Thanyaburi, Patumthani 12110, Thailand
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A novel olfactory pathway is essential for fast and efficient blood-feeding in mosquitoes. Sci Rep 2015; 5:13444. [PMID: 26306800 PMCID: PMC4549640 DOI: 10.1038/srep13444] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Accepted: 07/27/2015] [Indexed: 01/02/2023] Open
Abstract
In mosquitoes, precise and efficient finding of a host animal is crucial for survival. One of the poorly understood aspects of mosquito blood-feeding behavior is how these insects target an optimal site in order to penetrate the skin and blood vessels without alerting the host animal. Here we provide new findings that a piercing structure of the mouthpart of the mosquitoes, the stylet, is an essential apparatus for the stage in blood feeding. Indeed, the stylet possesses a number of sensory hairs located at the tip of the stylet. These hairs house olfactory receptor neurons that express two conventional olfactory receptors of Aedes aegypti (AaOrs), AaOr8 and AaOr49, together with the odorant co-receptor (AaOrco). In vivo calcium imaging using transfected cell lines demonstrated that AaOr8 and AaOr49 were activated by volatile compounds present in blood. Inhibition of gene expression of these AaOrs delayed blood feeding behaviors of the mosquito. Taken together, we identified olfactory receptor neurons in the stylet involved in mosquito blood feeding behaviors, which in turn indicates that olfactory perception in the stylet is necessary and sufficient for mosquitoes to find host blood in order to rapidly acquire blood meals from a host animal.
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Abd-Ella A, Stankiewicz M, Mikulska K, Nowak W, Pennetier C, Goulu M, Fruchart-Gaillard C, Licznar P, Apaire-Marchais V, List O, Corbel V, Servent D, Lapied B. The Repellent DEET Potentiates Carbamate Effects via Insect Muscarinic Receptor Interactions: An Alternative Strategy to Control Insect Vector-Borne Diseases. PLoS One 2015; 10:e0126406. [PMID: 25961834 PMCID: PMC4427492 DOI: 10.1371/journal.pone.0126406] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Accepted: 04/01/2015] [Indexed: 11/25/2022] Open
Abstract
Insect vector-borne diseases remain one of the principal causes of human mortality. In addition to conventional measures of insect control, repellents continue to be the mainstay for personal protection. Because of the increasing pyrethroid-resistant mosquito populations, alternative strategies to reconstitute pyrethroid repellency and knock-down effects have been proposed by mixing the repellent DEET (N,N-Diethyl-3-methylbenzamide) with non-pyrethroid insecticide to better control resistant insect vector-borne diseases. By using electrophysiological, biochemichal, in vivo toxicological techniques together with calcium imaging, binding studies and in silico docking, we have shown that DEET, at low concentrations, interacts with high affinity with insect M1/M3 mAChR allosteric site potentiating agonist effects on mAChRs coupled to phospholipase C second messenger pathway. This increases the anticholinesterase activity of the carbamate propoxur through calcium-dependent regulation of acetylcholinesterase. At high concentrations, DEET interacts with low affinity on distinct M1/M3 mAChR site, counteracting the potentiation. Similar dose-dependent dual effects of DEET have also been observed at synaptic mAChR level. Additionally, binding and in silico docking studies performed on human M1 and M3 mAChR subtypes indicate that DEET only displays a low affinity antagonist profile on these M1/M3 mAChRs. These results reveal a selective high affinity positive allosteric site for DEET in insect mAChRs. Finally, bioassays conducted on Aedes aegypti confirm the synergistic interaction between DEET and propoxur observed in vitro, resulting in a higher mortality of mosquitoes. Our findings reveal an unusual allosterically potentiating action of the repellent DEET, which involves a selective site in insect. These results open exciting research areas in public health particularly in the control of the pyrethroid-resistant insect-vector borne diseases. Mixing low doses of DEET and a non-pyrethroid insecticide will lead to improvement in the efficiency treatments thus reducing both the concentration of active ingredients and side effects for non-target organisms. The discovery of this insect specific site may pave the way for the development of new strategies essential in the management of chemical use against resistant mosquitoes.
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Affiliation(s)
- Aly Abd-Ella
- Laboratoire Récepteurs et Canaux Ioniques Membranaires (RCIM) UPRES EA 2647/USC INRA 1330, SFR 4207 QUASAV, Université d’Angers, UFR SCIENCES, Angers cedex, France
- Plant Protection Department, Faculty of Agriculture, Assiut University, Assiut, Egypt
| | - Maria Stankiewicz
- Faculty of Biology and Environment Protection, N. Copernicus University, Torun, Poland
| | - Karolina Mikulska
- Institute of Physics, Faculty of Physics, Astronomy and Informatics, N. Copernicus University, Torun, Poland
| | - Wieslaw Nowak
- Institute of Physics, Faculty of Physics, Astronomy and Informatics, N. Copernicus University, Torun, Poland
| | - Cédric Pennetier
- Institut de Recherche pour le Développement, UMR 224 Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MiVEGEC), Montpellier, France
| | - Mathilde Goulu
- Laboratoire Récepteurs et Canaux Ioniques Membranaires (RCIM) UPRES EA 2647/USC INRA 1330, SFR 4207 QUASAV, Université d’Angers, UFR SCIENCES, Angers cedex, France
| | - Carole Fruchart-Gaillard
- CEA, iBiTecS, Service d’Ingénierie Moléculaire des Protéines (SIMOPRO), Laboratoire de Toxinologie Moléculaire et Biotechnologie, Gif sur Yvette, France
| | - Patricia Licznar
- Laboratoire Récepteurs et Canaux Ioniques Membranaires (RCIM) UPRES EA 2647/USC INRA 1330, SFR 4207 QUASAV, Université d’Angers, UFR SCIENCES, Angers cedex, France
| | - Véronique Apaire-Marchais
- Laboratoire Récepteurs et Canaux Ioniques Membranaires (RCIM) UPRES EA 2647/USC INRA 1330, SFR 4207 QUASAV, Université d’Angers, UFR SCIENCES, Angers cedex, France
| | - Olivier List
- Laboratoire Récepteurs et Canaux Ioniques Membranaires (RCIM) UPRES EA 2647/USC INRA 1330, SFR 4207 QUASAV, Université d’Angers, UFR SCIENCES, Angers cedex, France
| | - Vincent Corbel
- Institut de Recherche pour le Développement, UMR 224 Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MiVEGEC), Montpellier, France
- Department of Entomology, Faculty of Agriculture at Kamphaeng Saen, Kamphaeng Saen Campus, Kasetsart University, Nakhon Pathom, Thailand
| | - Denis Servent
- CEA, iBiTecS, Service d’Ingénierie Moléculaire des Protéines (SIMOPRO), Laboratoire de Toxinologie Moléculaire et Biotechnologie, Gif sur Yvette, France
| | - Bruno Lapied
- Laboratoire Récepteurs et Canaux Ioniques Membranaires (RCIM) UPRES EA 2647/USC INRA 1330, SFR 4207 QUASAV, Université d’Angers, UFR SCIENCES, Angers cedex, France
- * E-mail:
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Iovinella I, Pelosi P, Conti B. A rationale to design longer lasting mosquito repellents. Parasitol Res 2014; 113:1813-20. [DOI: 10.1007/s00436-014-3827-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Accepted: 02/21/2014] [Indexed: 12/21/2022]
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Evaluation of the repellent effects of Nepeta parnassica extract, essential oil, and its major nepetalactone metabolite against mosquitoes. Parasitol Res 2014; 113:1127-34. [PMID: 24449446 DOI: 10.1007/s00436-013-3750-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2013] [Accepted: 12/26/2013] [Indexed: 10/25/2022]
Abstract
The dichloromethane-methanol extract, the essential oil obtained by hydrodistillation from Nepeta parnassica, and the isolated 4aα,7α,7aβ-nepetalactone were evaluated for their repellent effect against the mosquitoes Aedes (Stegomyia) cretinus Edwards and Culex pipiens pipiens biotype molestus Forskål. The chemical analysis of N. parnassica essential oil, dominated by oxygenated monoterpenes (87 %), revealed 4aα,7α,7aβ-nepetalactone (36.8%), 1,8-cineole (25.5%), and 4aα,7β,7aβ-nepetalactone (11.1%) as the major constituents. The results of the insect bioassays showed that the essential oil and the dichloromethane-methanol extract of N. parnassica were very active against Aedes cretinus for up to 3 h and against Culex pipiens for up to 2 h post application. The isolated 4aα,7α,7aβ-nepetalactone showed very high mosquito repellency for periods of at least 2 h against both species.
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41
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Liu F, Chen L, Appel AG, Liu N. Olfactory responses of the antennal trichoid sensilla to chemical repellents in the mosquito, Culex quinquefasciatus. JOURNAL OF INSECT PHYSIOLOGY 2013; 59:1169-77. [PMID: 24035746 DOI: 10.1016/j.jinsphys.2013.08.016] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Revised: 08/27/2013] [Accepted: 08/31/2013] [Indexed: 05/20/2023]
Abstract
Insect repellents are widely used to protect against insect bites and thus prevent allergic reaction and the spread of disease. To gain insight into the mosquito's response to chemicals repellents, we investigated the interaction between the olfactory system of the mosquito Culex quinquefasciatus Say and chemical repellents using single sensillum recording. The interactions of 50 repellent chemicals with olfactory receptor neurons were measured in six different types of mosquito sensilla: long sharp trichoid (LST), short sharp trichoid (SST), short blunt trichoid I (SBT-I), short blunt trichoid II (SBT-II), short blunt trichoid-curved (SBT-C), and grooved peg (GP). A single olfactory neuron reacted to the chemical repellents in each of the sensilla except for SBT-I and SBT-II, where two neurons were involved. Other than LST and GP, which showed no or very weak responses to the repellents tested, all the sensilla showed significant excitatory responses to certain types of repellents. Terpene-derived chemicals such as eucalyptol, α-pinene, and camphor, stimulated olfactory receptor neurons in a dose-dependent manner and mosquitoes responded more strongly to terpene-derived chemical repellents than to non-terpene-derived chemicals such as dimethyl phthalate. Mosquitoes also exhibited a similar response to stereoisomers of chemicals such as (-)-β-pinene versus (+)-β-pinene, and (-)-menthone versus (+)-menthone. This study not only demonstrates the effects of chemical repellents on the mosquito olfactory system but also provides important information that will assist those screening new mosquito repellents and designing new mosquito control agents.
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Affiliation(s)
- Feng Liu
- Department of Entomology and Plant Pathology, Auburn University, Auburn, AL 36849, USA
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42
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Oliferenko PV, Oliferenko AA, Poda GI, Osolodkin DI, Pillai GG, Bernier UR, Tsikolia M, Agramonte NM, Clark GG, Linthicum KJ, Katritzky AR. Promising Aedes aegypti repellent chemotypes identified through integrated QSAR, virtual screening, synthesis, and bioassay. PLoS One 2013; 8:e64547. [PMID: 24039693 PMCID: PMC3765160 DOI: 10.1371/journal.pone.0064547] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Accepted: 04/15/2013] [Indexed: 11/19/2022] Open
Abstract
Molecular field topology analysis, scaffold hopping, and molecular docking were used as complementary computational tools for the design of repellents for Aedes aegypti, the insect vector for yellow fever, chikungunya, and dengue fever. A large number of analogues were evaluated by virtual screening with Glide molecular docking software. This produced several dozen hits that were either synthesized or procured from commercial sources. Analysis of these compounds by a repellent bioassay resulted in a few highly active chemicals (in terms of minimum effective dosage) as viable candidates for further hit-to-lead and lead optimization effort.
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Affiliation(s)
- Polina V. Oliferenko
- Department of Chemistry, University of Florida, Gainesville, Florida, United States of America
| | - Alexander A. Oliferenko
- Department of Chemistry, University of Florida, Gainesville, Florida, United States of America
| | - Gennadiy I. Poda
- Medicinal Chemistry Platform, Ontario Institute for Cancer Research, Toronto, Ontario, Canada
| | | | - Girinath G. Pillai
- Department of Chemistry, University of Florida, Gainesville, Florida, United States of America
- Institute of Chemistry, University of Tartu, Tartu, Estonia
| | | | | | | | | | | | - Alan R. Katritzky
- Department of Chemistry, University of Florida, Gainesville, Florida, United States of America
- Chemistry Department, King Abdulaziz University, Jeddah, Saudi Arabia
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Xu P, Choo YM, Pelletier J, Sujimoto FR, Hughes DT, Zhu F, Atungulu E, Cornel AJ, Luetje CW, Leal WS. Silent, generic and plant kairomone sensitive odorant receptors from the Southern house mosquito. JOURNAL OF INSECT PHYSIOLOGY 2013; 59:961-6. [PMID: 23876610 PMCID: PMC3800014 DOI: 10.1016/j.jinsphys.2013.07.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2013] [Revised: 06/24/2013] [Accepted: 07/12/2013] [Indexed: 05/14/2023]
Abstract
The Southern house mosquito Culex quinquefasciatus has the largest repertoire of odorant receptors (ORs) of all mosquitoes and dipteran species whose genomes have been sequenced to date. Previously, we have identified and de-orphanized two ORs expressed in female antennae, CquiOR2 and CquiOR10, which are sensitive to oviposition attractants. In view of a new nomenclature for the Culex genome (VectorBase) we renamed these ORs as CquiOR21 (formerly CquiOR10) and CquiOR121 (CquiOR2). In addition, we selected ORs from six different phylogenetic groups for deorphanization. We cloned four of them by using cDNA from female antennae as a template. Attempts to clone CquiOR87 and CquiOR110 were unsuccessful either because they are pseudogenes or are not expressed in adult female antennae, the main olfactory tissue. By contrast, CquiOR1, CquiOR44, CquiOR73, and CquiOR161 were highly expressed in female antennae. To de-orphanize these ORs, we employed the Xenopus oocyte recording system. CquiORx-CquiOrco-expressed oocytes were challenged with a panel of 90 compounds, including known oviposition attractants, human and vertebrate host odorants, plant kairomones, and naturally occurring repellents. While CquiOR161 did not respond to any test compound in two different laboratories, CquiOR1 showed the features of a generic OR, with strong responses to 1-octen-3-ol and other ligands. CquiOR44 and CquiOR73 showed preference to plant-derived terpenoids and phenolic compounds, respectively. While fenchone was the best ligand for the former, 3,5-dimethylphenol elicited the strongest responses in the latter. The newly de-orphanized ORs may be involved in reception of plant kairomones and/or natural repellents.
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Affiliation(s)
- Pingxi Xu
- Department of Molecular and Cellular Biology, University of California, Davis, CA 95616 USA
| | - Young-Moo Choo
- Department of Molecular and Cellular Biology, University of California, Davis, CA 95616 USA
| | - Julien Pelletier
- Department of Molecular and Cellular Biology, University of California, Davis, CA 95616 USA
| | - Fernando R. Sujimoto
- Department of Molecular and Cellular Biology, University of California, Davis, CA 95616 USA
| | - David T. Hughes
- Department of Molecullar and Cellular Pharmacology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Fen Zhu
- Department of Molecular and Cellular Biology, University of California, Davis, CA 95616 USA
| | - Elizabeth Atungulu
- Department of Molecular and Cellular Biology, University of California, Davis, CA 95616 USA
| | - Anthony J. Cornel
- Department of Entomology and Namatology, Mosquito Control Research Laboratory, Kearney Agricultural Center, 9240 S. Riverbend Ave., Parlier, California 93648, USA
| | - Charles W. Luetje
- Department of Molecullar and Cellular Pharmacology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Walter S. Leal
- Department of Molecular and Cellular Biology, University of California, Davis, CA 95616 USA
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Fabbro SD, Nazzi F. From Chemistry to Behavior. Molecular Structure and Bioactivity of Repellents against Ixodes ricinus Ticks. PLoS One 2013; 8:e67832. [PMID: 23805329 PMCID: PMC3689731 DOI: 10.1371/journal.pone.0067832] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2013] [Accepted: 05/22/2013] [Indexed: 11/19/2022] Open
Abstract
Tick-borne zoonoses are considered as emerging diseases. Tick repellents represent an effective tool for reducing the risk of tick bite and pathogens transmission. Previous work demonstrated the repellent activity of the phenylpropanoid eugenol against Ixodes ricinus; here we investigate the relationship between molecular structure and repellency in a group of substances related to that compound. We report the biological activity of 18 compounds varying for the presence/number of several moieties, including hydroxyl and methoxy groups and carbon side-chain. Each compound was tested at different doses with a bioassay designed to measure repellency against individual tick nymphs. Both vapor pressure and chemical features of the tested compounds appeared to be related to repellency. In particular, the hydroxyl and methoxy groups as well as the side-chain on the benzene ring seem to play a role. These results are discussed in light of available data on chemical perception in ticks. In the course of the study new repellent compounds were identified; the biological activity of some of them (at least as effective as the “gold standard” repellent DEET) appears to be very promising from a practical point of view.
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Affiliation(s)
- Simone Del Fabbro
- Dipartimento di Scienze Agrarie e Ambientali, Università degli Studi di Udine, Udine, Italy
- * E-mail:
| | - Francesco Nazzi
- Dipartimento di Scienze Agrarie e Ambientali, Università degli Studi di Udine, Udine, Italy
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Song J, Wang Z, Findlater A, Han Z, Jiang Z, Chen J, Zheng W, Hyde S. Terpenoid mosquito repellents: a combined DFT and QSAR study. Bioorg Med Chem Lett 2013; 23:1245-8. [PMID: 23375229 DOI: 10.1016/j.bmcl.2013.01.015] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2012] [Revised: 12/20/2012] [Accepted: 01/02/2013] [Indexed: 10/27/2022]
Abstract
Interactions between low-toxicity terpenoid mosquito repellents and lactic acid are studied at the HF and B3LYP level. The subsequent QSAR study shows that not only the structure of repellents but also the repellent-lactic acid complexes may play an important role. It suggests that further study on interactions between repellents and characteristic compounds from human host may be required in order to understand the repelling mechanism.
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Affiliation(s)
- Jie Song
- Department of Chemistry, University of Michigan-Flint, 303E Kearsley, Flint, MI 48502, United States.
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Tong F, Coats JR. Quantitative structure-activity relationships of monoterpenoid binding activities to the housefly GABA receptor. PEST MANAGEMENT SCIENCE 2012; 68:1122-1129. [PMID: 22461383 DOI: 10.1002/ps.3280] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2011] [Revised: 01/01/2012] [Accepted: 01/25/2012] [Indexed: 05/31/2023]
Abstract
BACKGROUND Monoterpenoids are a large group of plant secondary metabolites. Many of these naturally occurring compounds have shown good insecticidal potency on pest insects. Previous studies in this laboratory have indicated that some monoterpenoids have positive modulatory effects on insect GABA receptors. In this study, the key properties of monoterpenoids involved in monoterpenoid binding activity at the housefly GABA receptor were determined by developing quantitative structure-activity relationship (QSAR) models, and the relationship between the toxicities of these monoterpenoids and their GABA receptor binding activities was evaluated. RESULTS Two QSAR models were determined for nine monoterpenoids showing significant effects on [³H]-TBOB binding and for nine p-menthane analogs with at least one oxygen atom attached to the ring. The Mulliken charges on certain carbon atoms, the log P value and the total energy showed significant relationships with binding activities to the housefly GABA receptor in these two QSAR models. CONCLUSIONS From the QSAR models, some chemical and structural parameters, including the electronic properties, hydrophobicity and stability of monoterpenoid molecules, were suggested to be strongly involved in binding activities to the housefly GABA receptor. These findings will help to understand the mode of action of these natural insecticides, and provide guidance to predict more monoterpenoid insecticides.
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Affiliation(s)
- Fan Tong
- Pesticide Toxicology Laboratory, Department of Entomology, Iowa State University, Ames, IA, USA
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Waliwitiya R, Nicholson RA, Kennedy CJ, Lowenberger CA. The synergistic effects of insecticidal essential oils and piperonyl butoxide on biotransformational enzyme activities in Aedes aegypti (Diptera: Culicidae). JOURNAL OF MEDICAL ENTOMOLOGY 2012; 49:614-23. [PMID: 22679869 DOI: 10.1603/me10272] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
The biochemical mechanisms underlying the increased toxicity of several plant essential oils (thymol, eugenol, pulegone, terpineol, and citronellal) against fourth instar of Aedes aegypti L. when exposed simultaneously with piperonyl butoxide (PBO) were examined. Whole body biotransformational enzyme activities including cytochrome P450-mediated oxidation (ethoxyresorufin O-dethylase [EROD]), glutathione S-transferase (GST), and beta-esterase activity were measured in control, essential oil-exposed only (single chemical), and essential oil + PBO (10 mg/liter) exposed larvae. At high concentrations, thymol, eugenol, pulegone, and citronellal alone reduced EROD activity by 5-25% 16 h postexposure. Terpineol at 10 mg/liter increased EROD activity by 5 +/- 1.8% over controls. The essential oils alone reduced GST activity by 3-20% but PBO exposure alone did not significantly affect the activity of any of the measured enzymes. All essential oils in combination with PBO reduced EROD activity by 58-76% and reduced GST activity by 3-85% at 16 h postexposure. This study indicates a synergistic interaction between essential oils and PBO in inhibiting the cytochrome P450 and GST detoxification enzymes in Ae. aegypti.
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Affiliation(s)
- Ranil Waliwitiya
- Department of Biological Sciences, Simon Fraser University, 8888 University Drive, Burnaby, British Columbia, Canada, V5A 1S6.
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48
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Rinker DC, Jones PL, Pitts RJ, Rutzler M, Camp G, Sun L, Xu P, Weaver D, Zwiebel LJ. Novel high-throughput screens of Anopheles gambiae odorant receptors reveal candidate behaviour-modifying chemicals for mosquitoes. PHYSIOLOGICAL ENTOMOLOGY 2012; 37:33-41. [PMID: 32255891 PMCID: PMC7123412 DOI: 10.1111/j.1365-3032.2011.00821.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Despite many decades of multilateral global efforts, a significant portion of the world population continues to be plagued with one or more mosquito-vectored diseases. These include malaria and filariasis as well as numerous arboviral-associated illnesses including Dengue and Yellow fevers. The dynamics of disease transmission by mosquitoes is complex, and involves both vector competence and vectorial capacity. One area of intensive effort is the study of chemosensory-driven behaviours in the malaria vector mosquito Anopheles gambiae Giles, the modulation of which are likely to provide opportunities for disease reduction. In this context recent studies have characterized a large divergent family of An. gambiae odorant receptors (AgORs) that play critical roles in olfactory signal transduction. This work has facilitated high-throughput, cell-based calcium mobilization screens of AgOR-expressing HEK cells that have identified a large number of conventional AgOR ligands, as well as the first non-conventional Orco (olfactory receptor co-receptor) family agonist. As such, ligand-mediated modulation serves as a proof-of-concept demonstration that AgORs represent viable targets for high-throughput screening and for the eventual development of behaviour-modifying olfactory compounds. Such attractants or repellents could foster malaria reduction programmes.
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Affiliation(s)
- David C. Rinker
- Center for Human Genetics Training Program, Vanderbilt University Medical Centre, Nashville, U.S.A
| | - Patrick L. Jones
- Department of Biological Sciences, Vanderbilt University, Nashville, U.S.A
| | - R. Jason Pitts
- Department of Biological Sciences, Vanderbilt University, Nashville, U.S.A
| | - Michael Rutzler
- Department of Biological Sciences, Vanderbilt University, Nashville, U.S.A
| | - Gray Camp
- Department of Biological Sciences, Vanderbilt University, Nashville, U.S.A
| | - Lujuan Sun
- Department of Biological Sciences, Vanderbilt University, Nashville, U.S.A
| | - Pingxi Xu
- Department of Biological Sciences, Vanderbilt University, Nashville, U.S.A
| | - David Weaver
- Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, U.S.A
| | - Laurence J Zwiebel
- Department of Biological Sciences, Vanderbilt University, Nashville, U.S.A
- Department of Pharmacology, Vanderbilt University Medical Centre, Nashville, U.S.A
- Center for Molecular Neuroscience, Institute of Global Health and Program in Developmental Biology, Vanderbilt University Medical Centre, Nashville, U.S.A
- Center for Human Genetics Training Program, Vanderbilt University Medical Centre, Nashville, U.S.A
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49
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Peterson CJ, Coats JR. Catnip Essential Oil and Its Nepetalactone Isomers as Repellents for Mosquitoes. ACTA ACUST UNITED AC 2011. [DOI: 10.1021/bk-2011-1090.ch004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Affiliation(s)
| | - Joel R. Coats
- Department of Entomology, Iowa State University, Ames, Iowa 50011
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50
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Bohbot JD, Fu L, LE TC, Chauhan KR, Cantrell CL, Dickens JC. Multiple activities of insect repellents on odorant receptors in mosquitoes. MEDICAL AND VETERINARY ENTOMOLOGY 2011; 25:436-444. [PMID: 21395633 DOI: 10.1111/j.1365-2915.2011.00949.x] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Several lines of evidence suggest that insect repellent molecules reduce mosquito-host contacts by interacting with odorants and odorant receptors (ORs), thereby ultimately affecting olfactory-driven behaviours. We describe the molecular effects of 10 insect repellents and a pyrethroid insecticide with known repellent activity on two highly specific Aedes aegypti (Diptera: Culicidae) ORs, AaOR2 + AaOR7 and AaOR8 + AaOR7, exquisitely sensitive to key mosquito attractants indole and (R)-(-)-1-octen-3-ol, expressed in oocytes of Xenopus (Anura: Pipidae). Our study demonstrates that insect repellents can both inhibit odorant-evoked currents mediated by ORs and independently elicit currents in the absence of odorants. All of the repellents had effects on one or both ORs; most of these compounds were selective inhibitors and showed a high degree of specificity in their capacity to activate the two ORs. These results show that a range of insect repellents belonging to structurally diverse chemical classes modulate the function of mosquito ORs through multiple molecular mechanisms.
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Affiliation(s)
- J D Bohbot
- Invasive Insect Biocontrol and Behavior Laboratory, Plant Sciences Institute, U.S. Department of Agriculture-Agricultural Research Service (USDA-ARS), Henry A. Wallace Beltsville Agricultural Research Center, Beltsville, MD, U.S.A.
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