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Opoku-Bamfoh O, Kwarteng SA, Owusu FAN, Akpanya R, Mensah KA, Badu M, Gyamfi FY, Sogbo V, Belford EJD, Boakye A, Morrison HM, Obuam PK, Coleman S. Repellent and larvicidal properties of selected indigenous plants in the control of Anopheles mosquitoes. J Vector Borne Dis 2024; 61:90-100. [PMID: 38648410 DOI: 10.4103/0972-9062.392267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Accepted: 08/18/2023] [Indexed: 04/25/2024] Open
Abstract
BACKGROUND OBJECTIVES Widespread pyrethroid resistance and plastic-feeding behaviour of most malaria vectors across Africa threaten the efficacy of current insecticide-based vector control interventions like Insecticide-Treated Nets (ITNs) and Indoor Residual Spraying (IRS). This study examined the larvicidal activity ofMorinda citrifolia against Anopheles gambiae larvae and the repellent properties of Morinda citrifolia (Noni), Moringa oleifera (Moringa), and Ocimum basilicum (Basil) as complementary vector control tools against Anopheles gambiae sensu lato (s.l.). METHODS Noni, Basil, and Moringa oil extracts were obtained with the extraction techniques; Soxhlet, steam distillation and maceration respectively, using hexane and ethanol. The effectiveness of the extracts was assessed using the WHO standard larval susceptibility bioassay and guidelines for repellent efficacy. Following bioassays, effective doses (ED) and lethal concentrations (LC) were determined. Gas Chromatography-Mass Spectroscopy analysis was performed to identify the bioactive chemical components of the extracts of Moringa oleifera and Ocimum basilicum. RESULTS Emulsified Morinda citrifolia seed oil had LC50=68.3, LC90=130.9 and LC99.9=222.5, and ED99. 9=308.3%v/v, the ethanolic extract of Moringa oleifera leaves had ED99.9= 1.25g/ml, and essential oil of Ocimum basilicum leaves had ED99.9=0.28g/ml against Anopheles gambiae. INTERPRETATION CONCLUSION The results obtained indicated that seed oil of Morinda citrifolia, essential oil of Ocimum basilicum, and crude extract of Moringa oleifera have repellent activity against An. gambiae s.l. The complete protection time (CPT) of Morinda citrifolia, Moringa oleifera, and Ocimum basilicum was 120 min, 72 min and 84 min at ED99.9 respectively. Morinda citrifolia oil exhibited larvicidal effects against the larvae of An. gambiae s.l. The results provide valuable information for the use of the plants as biocides.
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Affiliation(s)
- Obadiah Opoku-Bamfoh
- Department of Theoretical and Applied Biology, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Sandra Abankwa Kwarteng
- Department of Theoretical and Applied Biology, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Frema A N Owusu
- Department of Theoretical and Applied Biology, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Raphael Akpanya
- Department of Theoretical and Applied Biology, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Kelvin A Mensah
- Department of Theoretical and Applied Biology, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Mercy Badu
- Department of Chemistry, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Fred Y Gyamfi
- Department of Theoretical and Applied Biology, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Victoria Sogbo
- Department of Theoretical and Applied Biology, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Ebenezer J D Belford
- Department of Theoretical and Applied Biology, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Abena Boakye
- Department of Food Science and Technology, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Henry Morgan Morrison
- Department of Theoretical and Applied Biology, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Patrick K Obuam
- School of Public Health, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Sylvester Coleman
- Department of Clinical Microbiology, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
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Dötterl S, Gershenzon J. Chemistry, biosynthesis and biology of floral volatiles: roles in pollination and other functions. Nat Prod Rep 2023; 40:1901-1937. [PMID: 37661854 DOI: 10.1039/d3np00024a] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/05/2023]
Abstract
Covering: 2010 to 2023Floral volatiles are a chemically diverse group of plant metabolites that serve multiple functions. Their composition is shaped by environmental, ecological and evolutionary factors. This review will summarize recent advances in floral scent research from chemical, molecular and ecological perspectives. It will focus on the major chemical classes of floral volatiles, on notable new structures, and on recent discoveries regarding the biosynthesis and the regulation of volatile emission. Special attention will be devoted to the various functions of floral volatiles, not only as attractants for different types of pollinators, but also as defenses of flowers against enemies. We will also summarize recent findings on how floral volatiles are affected by abiotic stressors, such as increased temperatures and drought, and by other organisms, such as herbivores and flower-dwelling microbes. Finally, this review will indicate current research gaps, such as the very limited knowledge of the isomeric pattern of chiral compounds and its importance in interspecific interactions.
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Affiliation(s)
- Stefan Dötterl
- Department of Environment & Biodiversity, Paris Lodron University Salzburg, Hellbrunnerstr 34, 5020 Salzburg, Austria.
| | - Jonathan Gershenzon
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, 07745 Jena, Germany.
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Plirat W, Chaniad P, Phuwajaroanpong A, Konyanee A, Viriyavejakul P, Septama AW, Punsawad C. Efficacy of artesunate combined with Atractylodes lancea or Prabchompoothaweep remedy extracts as adjunctive therapy for the treatment of cerebral malaria. BMC Complement Med Ther 2023; 23:332. [PMID: 37730604 PMCID: PMC10510250 DOI: 10.1186/s12906-023-04150-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Accepted: 09/04/2023] [Indexed: 09/22/2023] Open
Abstract
BACKGROUND Cerebral malaria is one of the most serious complications of Plasmodium infection and causes behavioral changes. However, current antimalarial drugs have shown poor outcomes. Therefore, new antimalarials with neuroprotective effects are urgently needed. This study aimed to evaluate the effects of selected extracts as monotherapy or adjunctive therapy with artesunate on antimalarial, anti-inflammatory, antioxidant, and neuroprotective properties in experimental cerebral malaria (ECM). METHODS ECM was induced in male C57BL/6 mice by infection with Plasmodium berghei ANKA (PbA). Ethanolic extracts of Atractylodes lancea (a dose of 400 mg/kg) and Prabchompoothaweep remedy (a dose of 600 mg/kg) were evaluated as monotherapy and adjunctive therapy combined with artesunate at the onset of signs of cerebral malaria and continued for 7 consecutive days. Parasitemia, clinical scores, and body weight were recorded throughout the study. At day 13 post-infection, mouse brains were dissected and processed for the study of the inflammatory response, oxidative stress, blood-brain barrier (BBB) integrity, histopathological changes, and neurocognitive impairments. RESULTS Ethanolic extracts of A. lancea and Prabchompoothaweep remedy alone improved cerebral malaria outcome in ECM, whereas artesunate combined with extracts of A. lancea or Prabchompoothaweep remedy significantly improved the outcome of artesunate and crude extracts alone. Using real-time PCR, PbA-infected mice that had received the combination treatment showed significantly reduced gene expression of inflammatory cytokines (TNF-α, IL-1β, IL-6, and IL-10), chemokines (CXCL4 and CXCL10), and adhesion molecules (ICAM-1, VCAM1, and CD36). The PbA-infected mice that received the combination treatment showed a significantly decreased malondialdehyde level compared to the untreated group. Similarly, the Evans blue dye assay revealed significantly less dye extravasation in the brains of infected mice administered the combination treatment, indicating improved BBB integrity. Combination treatment improved survival and reduced pathology in the PbA-infected group. Additionally, combination treatment resulted in a significantly reduced level of cognitive impairment, which was analyzed using a novel object recognition test. CONCLUSIONS This study demonstrated that artesunate combined with A. lancea or Prabchompoothaweep remedy extracts as adjunctive therapy reduced mortality, neuroinflammation, oxidative stress, BBB integrity protection, and neurocognitive impairment in the ECM.
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Affiliation(s)
- Walaiporn Plirat
- Department of Medical Sciences, School of Medicine, Walailak University, Nakhon Si Thammarat, Thailand
- Research Center in Tropical Pathobiology, Walailak University, Nakhon Si Thammarat, 80160, Thailand
| | - Prapaporn Chaniad
- Department of Medical Sciences, School of Medicine, Walailak University, Nakhon Si Thammarat, Thailand
- Research Center in Tropical Pathobiology, Walailak University, Nakhon Si Thammarat, 80160, Thailand
| | - Arisara Phuwajaroanpong
- Department of Medical Sciences, School of Medicine, Walailak University, Nakhon Si Thammarat, Thailand
- Research Center in Tropical Pathobiology, Walailak University, Nakhon Si Thammarat, 80160, Thailand
| | - Atthaphon Konyanee
- Department of Medical Sciences, School of Medicine, Walailak University, Nakhon Si Thammarat, Thailand
- Research Center in Tropical Pathobiology, Walailak University, Nakhon Si Thammarat, 80160, Thailand
| | | | - Abdi Wira Septama
- Research Center for Pharmaceutical Ingredient and Traditional Medicine, National Research and Innovation Agency (BRIN), Cibinong Science Center, Cibinong, West Java, 16915, Indonesia
| | - Chuchard Punsawad
- Department of Medical Sciences, School of Medicine, Walailak University, Nakhon Si Thammarat, Thailand.
- Research Center in Tropical Pathobiology, Walailak University, Nakhon Si Thammarat, 80160, Thailand.
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Giatropoulos A, Koliopoulos G, Pantelakis PN, Papachristos D, Michaelakis A. Evaluating the Sublethal Effects of Origanum vulgare Essential Oil and Carvacrol on the Biological Characteristics of Culex pipiens biotype molestus (Diptera: Culicidae). INSECTS 2023; 14:400. [PMID: 37103215 PMCID: PMC10146918 DOI: 10.3390/insects14040400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 04/15/2023] [Accepted: 04/17/2023] [Indexed: 06/19/2023]
Abstract
Culex pipiens is a mosquito species complex spread worldwide that poses a serious threat to human health as the primary vector of West Nile virus. Its control is mainly based on larvicidal applications with synthetic insecticides on mosquito breeding sites. However, the excessive use of synthetic larvicides may provoke mosquito resistance issues and negative side effects to the aquatic environment and human health. Plant-derived essential oils, including those from the Lamiaceae family, can be eco-friendly alternative larvicidal agents causing acute larval toxicity and/or growth inhibitory effects on the developmental stages of mosquitoes through different modes of action. In the current laboratory study, we evaluated the sublethal effects of carvacrol-rich oregano essential oil and pure carvacrol on Cx. pipiens biotype molestus, the autogenous member of the Cx. pipiens species complex, after the exposure of 3rd-4th instar larvae to LC50 concentrations. The short-term (24 h) larvicidal treatment with the sublethal concentrations of both tested materials exhibited an acute lethal effect on the exposed larvae as well as significant delayed mortality for surviving larvae and pupae. Larvicidal treatment with carvacrol reduced the longevity of the emerged males. In addition, the morphological abnormalities that were observed at the larval and pupal stage along with failed adult emergence indicate the potential growth inhibitory properties of the tested bioinsecticides. Our findings suggest that carvacrol and carvacrol-rich oregano oil are effective plant-based larvicides at doses lower than the acute lethal ones, thus promoting an environmentally friendly and more affordable perspective for their use against the WNV vector Cx. pipiens biotype molestus.
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Affiliation(s)
- Athanasios Giatropoulos
- Laboratory of Efficacy Control of Pesticides, Benaki Phytopathological Institute, 14561 Kifissia, Greece
| | - George Koliopoulos
- Laboratory of Agricultural Zoology and Entomology, Agricultural University of Athens, 11855 Athens, Greece
| | - Pavlos-Nektarios Pantelakis
- Laboratory of Efficacy Control of Pesticides, Benaki Phytopathological Institute, 14561 Kifissia, Greece
- Laboratory of Agricultural Zoology and Entomology, Agricultural University of Athens, 11855 Athens, Greece
| | - Dimitrios Papachristos
- Laboratory of Agricultural Entomology, Benaki Phytopathological Institute, 14561 Kifissia, Greece
| | - Antonios Michaelakis
- Laboratory of Insects and Parasites of Medical Importance, Benaki Phytopathological Institute, 14561 Kifissia, Greece
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Martello E, Yogeswaran G, Reithinger R, Leonardi-Bee J. Mosquito aquatic habitat modification and manipulation interventions to control malaria. Cochrane Database Syst Rev 2022; 11:CD008923. [PMID: 36367444 PMCID: PMC9651131 DOI: 10.1002/14651858.cd008923.pub3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND Larval source management (LSM) may help reduce Plasmodium parasite transmission in malaria-endemic areas. LSM approaches include habitat modification (permanently or temporarily reducing mosquito breeding aquatic habitats); habitat manipulation (temporary or recurrent change to environment); or use of chemical (e.g. larviciding) or biological agents (e.g. natural predators) to breeding sites. We examined the effectiveness of habitat modification or manipulation (or both), with and without larviciding. This is an update of a review published in 2013. OBJECTIVES 1. To describe and summarize the interventions on mosquito aquatic habitat modification or mosquito aquatic habitat manipulation, or both, on malaria control. 2. To evaluate the beneficial and harmful effects of mosquito aquatic habitat modification or mosquito aquatic habitat manipulation, or both, on malaria control. SEARCH METHODS We used standard, extensive Cochrane search methods. The latest search was from January 2012 to 30 November 2021. SELECTION CRITERIA Randomized controlled trials (RCT) and non-randomized intervention studies comparing mosquito aquatic habitat modification or manipulation (or both) to no treatment or another active intervention. We also included uncontrolled before-after (BA) studies, but only described and summarized the interventions from studies with these designs. Primary outcomes were clinical malaria incidence, malaria parasite prevalence, and malaria parasitaemia incidence. DATA COLLECTION AND ANALYSIS We used standard Cochrane methods. We assessed risk of bias using the Cochrane RoB 2 tool for RCTs and the ROBINS-I tool for non-randomized intervention studies. We used a narrative synthesis approach to systematically describe and summarize all the interventions included within the review, categorized by the type of intervention (habitat modification, habitat manipulation, combination of habitat modification and manipulation). Our primary outcomes were 1. clinical malaria incidence; 2. malaria parasite prevalence; and 3. malaria parasitaemia incidence. Our secondary outcomes were 1. incidence of severe malaria; 2. anaemia prevalence; 3. mean haemoglobin levels; 4. mortality rate due to malaria; 5. hospital admissions for malaria; 6. density of immature mosquitoes; 7. density of adult mosquitoes; 8. sporozoite rate; 9. entomological inoculation rate; and 10. HARMS We used the GRADE approach to assess the certainty of the evidence for each type of intervention. MAIN RESULTS Sixteen studies met the inclusion criteria. Six used an RCT design, six used a controlled before-after (CBA) study design, three used a non-randomized controlled design, and one used an uncontrolled BA study design. Eleven studies were conducted in Africa and five in Asia. Five studies reported epidemiological outcomes and 15 studies reported entomological outcomes. None of the included studies reported on the environmental impacts associated with the intervention. For risk of bias, all trials had some concerns and other designs ranging from moderate to critical. Ten studies assessed habitat manipulation (temporary change to the environment). This included water management (spillways across streams; floodgates; intermittent flooding; different drawdown rates of water; different flooding and draining regimens), shading management (shading of drainage channels with different plants), other/combined management approaches (minimal tillage; disturbance of aquatic habitats with grass clearing and water replenishment), which showed mixed results for entomological outcomes. Spillways across streams, faster drawdown rates of water, shading drainage canals with Napier grass, and using minimal tillage may reduce the density of immature mosquitoes (range of effects from 95% reduction to 1.7 times increase; low-certainty evidence), and spillways across streams may reduce densities of adult mosquitoes compared to no intervention (low-certainty evidence). However, the effect of habitat manipulation on malaria parasite prevalence and clinical malaria incidence is uncertain (very low-certainty evidence). Two studies assessed habitat manipulation with larviciding. This included reducing or removal of habitat sites; and drain cleaning, grass cutting, and minor repairs. It is uncertain whether drain cleaning, grass cutting, and minor repairs reduces malaria parasite prevalence compared to no intervention (odds ratio 0.59, 95% confidence interval (CI) 0.42 to 0.83; very low-certainty evidence). Two studies assessed combination of habitat manipulation and permanent change (habitat modification). This included drainage canals, filling, and planting of papyrus and other reeds for shading near dams; and drainage of canals, removal of debris, land levelling, and filling ditches. Studies did not report on epidemiological outcomes, but entomological outcomes suggest that such activities may reduce the density of adult mosquitoes compared to no intervention (relative risk reduction 0.49, 95% CI 0.47 to 0.50; low-certainty evidence), and preventing water stagnating using drainage of canals, removal of debris, land levelling, and filling ditches may reduce the density of immature mosquitoes compared to no intervention (ranged from 10% to 55% reductions; low-certainty evidence). Three studies assessed combining manipulation and modification with larviciding. This included filling or drainage of water bodies; filling, draining, or elimination of rain pools and puddles at water supply points and stream bed pools; and shoreline work, improvement and maintenance to drainage, clearing vegetation and undergrowth, and filling pools. There were mixed effect sizes for the reduction of entomological outcomes (moderate-certainty evidence). However, filling or draining water bodies probably makes little or no difference to malaria parasite prevalence, haemoglobin levels, or entomological inoculation rate when delivered with larviciding compared to no intervention (moderate-certainty evidence). AUTHORS' CONCLUSIONS Habitat modification and manipulation interventions for preventing malaria has some indication of benefit in both epidemiological and entomological outcomes. While the data are quite mixed and further studies could help improve the knowledge base, these varied approaches may be useful in some circumstances.
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Affiliation(s)
- Elisa Martello
- Centre for Evidence Based Healthcare, Division of Epidemiology and Public Health, Clinical Sciences Building Phase 2, University of Nottingham, Nottingham, UK
| | - Gowsika Yogeswaran
- Centre for Evidence Based Healthcare, Division of Epidemiology and Public Health, Clinical Sciences Building Phase 2, University of Nottingham, Nottingham, UK
| | | | - Jo Leonardi-Bee
- Centre for Evidence Based Healthcare, Division of Epidemiology and Public Health, Clinical Sciences Building Phase 2, University of Nottingham, Nottingham, UK
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Giatropoulos A, Karamaouna F, Ampatzi A, Papachristos D, Michaelakis A. Sublethal effects of oregano essential oil and its major compound carvacrol on biological parameters of Aedes albopictus (Diptera: Culicidae). Exp Parasitol 2022; 242:108392. [PMID: 36191614 DOI: 10.1016/j.exppara.2022.108392] [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] [Received: 06/07/2022] [Revised: 09/22/2022] [Accepted: 09/23/2022] [Indexed: 11/18/2022]
Abstract
Mosquito management programs rely basically on the use of conventional synthetic larvicides. However, frequent applications and misuse of some synthetic insecticides have led to problems related to mosquito resistance development, harmful effects on human health and unacceptable environmental effects on non-target organisms. Recently, a growing number of phytochemicals has been tested as more eco-friendly larvicides against various mosquito species, exerting high efficacy with multiple modes of action. In the laboratory, we investigated for the first time the sublethal effects of oregano oil and its major compound carvacrol, against Aedes albopictus (Asian tiger mosquito), a mosquito of great medical importance. We determined the effects of short term (24h) exposure of 3rd- 4th larvae to LC50 concentrations on survival and development of survived larvae until adulthood, as well as on fecundity, fertility, longevity and wing length of emerged adults. Only half of 24h survived larvae from oregano oil and carvacrol treatment finally reached adulthood. Abnormal shapes of dead larvae and pupae, and failed adult emergence were also observed, indicating a potential growth inhibitory activity of the tested materials. No particular effects from exposure to larvicidal LC50 concentrations were recorded on life cycle parameters of successfully emerged adults. These findings suggest the tested oregano oil and carvacrol as sufficiently effective larvicides against Ae. albopictus at lower than the acutely toxic concentrations, promoting a more eco-friendly and less costly profile for these biopesticides.
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Affiliation(s)
- Athanasios Giatropoulos
- Laboratory of Efficacy Control of Pesticides, Benaki Phytopathological Institute, 14561, Kifissia, Greece.
| | - Filitsa Karamaouna
- Laboratory of Efficacy Control of Pesticides, Benaki Phytopathological Institute, 14561, Kifissia, Greece
| | - Argyro Ampatzi
- Laboratory of Efficacy Control of Pesticides, Benaki Phytopathological Institute, 14561, Kifissia, Greece
| | - Dimitrios Papachristos
- Laboratory of Agricultural Entomology, Benaki Phytopathological Institute, 14561, Kifissia, Greece
| | - Antonios Michaelakis
- Laboratory of Insects and Parasites of Medical Importance, Benaki Phytopathological Institute, 14561, Kifissia, Greece
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Muema JM, Bargul JL, Obonyo MA, Njeru SN, Matoke-Muhia D, Mutunga JM. Contemporary exploitation of natural products for arthropod-borne pathogen transmission-blocking interventions. Parasit Vectors 2022; 15:298. [PMID: 36002857 PMCID: PMC9404607 DOI: 10.1186/s13071-022-05367-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Accepted: 06/16/2022] [Indexed: 11/26/2022] Open
Abstract
An integrated approach to innovatively counter the transmission of various arthropod-borne diseases to humans would benefit from strategies that sustainably limit onward passage of infective life cycle stages of pathogens and parasites to the insect vectors and vice versa. Aiming to accelerate the impetus towards a disease-free world amid the challenges posed by climate change, discovery, mindful exploitation and integration of active natural products in design of pathogen transmission-blocking interventions is of high priority. Herein, we provide a review of natural compounds endowed with blockade potential against transmissible forms of human pathogens reported in the last 2 decades from 2000 to 2021. Finally, we propose various translational strategies that can exploit these pathogen transmission-blocking natural products into design of novel and sustainable disease control interventions. In summary, tapping these compounds will potentially aid in integrated combat mission to reduce disease transmission trends.
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Affiliation(s)
- Jackson M Muema
- Department of Biochemistry, Jomo Kenyatta University of Agriculture and Technology (JKUAT), P.O. Box 62000, Nairobi, 00200, Kenya.
| | - Joel L Bargul
- Department of Biochemistry, Jomo Kenyatta University of Agriculture and Technology (JKUAT), P.O. Box 62000, Nairobi, 00200, Kenya.,International Centre of Insect Physiology and Ecology (Icipe), P.O. Box 30772, Nairobi, 00100, Kenya
| | - Meshack A Obonyo
- Department of Biochemistry and Molecular Biology, Egerton University, P.O. Box 536, Egerton, 20115, Kenya
| | - Sospeter N Njeru
- Centre for Traditional Medicine and Drug Research (CTMDR), Kenya Medical Research Institute (KEMRI), P.O. Box 54840, Nairobi, 00200, Kenya
| | - Damaris Matoke-Muhia
- Centre for Biotechnology Research Development (CBRD), Kenya Medical Research Institute (KEMRI), P.O. Box 54840, Nairobi, 00200, Kenya
| | - James M Mutunga
- Department of Biological Sciences, Mount Kenya University (MKU), P.O. Box 54, Thika, 01000, Kenya.,School of Engineering Design, Technology and Professional Programs, Pennsylvania State University, University Park, PA, 16802, USA
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Mota TF, Silva CMDA, Conceição MDS, Fraga DBM, Brodskyn CI, Neto MFDA, Santana IB, Mesquita PRR, Leite FHA, Magalhães-Júnior JT. Screening organic repellent compounds against Lutzomyia longipalpis (Diptera: Psychodidae) present in plant essential oils: Bioassay plus an in silico approach. Acta Trop 2022; 229:106367. [PMID: 35167802 DOI: 10.1016/j.actatropica.2022.106367] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 02/09/2022] [Accepted: 02/10/2022] [Indexed: 11/18/2022]
Abstract
In the Americas, Lutzomyia longipalpis is the most relevant sand fly species for the transmission of visceral leishmaniasis. For its vector control in Brazil, insecticide spraying has not shown persistent reduction in disease prevalence while some sand fly populations are reported resistant to the insecticides used in spraying. The usage of repellents and personal protection behavior can reduce vector borne diseases prevalence. Therefore, the search for new repellent compounds is needed to use together with insecticide spraying, especially from natural sources to overcome the resistance developed by some sand fly populations to the compounds commercially used. In silico strategies have been applied together with repellency bioassays successfully identifying new bioactive compounds from natural sources. Thus, the present study aimed to screen repellent potential of neem (Azadirachta indica), citronella (Cymbopogon winterianus), bushy matgrass (Lippia alba) and 'alecrim do mato' (Lippia thymoides) essential oils against L. longipalpis and to identify potential repellent compounds by chemical analysis and in silico approach. Plant essential oils were extracted from leaves and repellency bioassays were performed on volunteers using colony reared L. longipalpis. Aside from neem oil, all other tested essential oil has shown a reduced number of sand fly bites using higher concentrations. Chemical composition from oils was assessed and its compounds were screened on a pharmacophore model using odorant binding protein 1 (OBP1). All essential oils were majorly composed of either oxygenated monoterpenes, except for the oil extracted from neem which was composed of sesquiterpene hydrocarbons. Molecular docking was performed with the compounds that best superimposed in the OBP1 pharmacophore model, identifying those binding to OBP4, which is associated with insect repellency behavior. Citronellol, Citronellol acetate, Citronellal and Geranyl acetate showed similar interactions with OBP4 binding site as DEET. Thus, it is suggested that these compounds are able to bind to L. longipalpis OBP4 generating repellent behavior in sand flies.
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Affiliation(s)
- Tiago F Mota
- Laboratório de Interação Parasito-Hospedeiro e Epidemiologia (LaIPHE), Instituto Gonçalo Moniz (IGM), FIOCRUZ-BA, Rua Waldemar Falcão, 121 Candeal, 40296-710, Salvador, Bahia, Brazil.
| | - Caliene M de A Silva
- Centro Multidisciplinar do Campus de Barra da Universidade Federal do Oeste da Bahia, Bahia, Brasil
| | - Maurício Dos S Conceição
- Centro Multidisciplinar do Campus de Barra da Universidade Federal do Oeste da Bahia, Bahia, Brasil
| | - Deborah B M Fraga
- Laboratório de Interação Parasito-Hospedeiro e Epidemiologia (LaIPHE), Instituto Gonçalo Moniz (IGM), FIOCRUZ-BA, Rua Waldemar Falcão, 121 Candeal, 40296-710, Salvador, Bahia, Brazil; Departamento de Medicina Veterinária Preventiva e Produção Animal, Escola de Medicina Veterinária e Zootecnia, Universidade Federal da Bahia (UFBA), Av. Adhemar de Barros, 500 Ondina, 40170-110, Salvador, Bahia, Brazil
| | - Claudia I Brodskyn
- Laboratório de Interação Parasito-Hospedeiro e Epidemiologia (LaIPHE), Instituto Gonçalo Moniz (IGM), FIOCRUZ-BA, Rua Waldemar Falcão, 121 Candeal, 40296-710, Salvador, Bahia, Brazil
| | - Moysés F de A Neto
- Laboratório de Modelagem Molecular, Departamento de Saúde, Universidade Estadual de Feira de Santana, Bahia, Brasil
| | - Isis B Santana
- Laboratório de Modelagem Molecular, Departamento de Saúde, Universidade Estadual de Feira de Santana, Bahia, Brasil
| | - Paulo R R Mesquita
- Centro Tecnológico Agropecuário do Estado da Bahia (CETAB), Bahia, Brazil; Faculdade Maria Milza, Bahia, Brazil
| | - Franco H A Leite
- Laboratório de Modelagem Molecular, Departamento de Saúde, Universidade Estadual de Feira de Santana, Bahia, Brasil
| | - Jairo T Magalhães-Júnior
- Centro Multidisciplinar do Campus de Barra da Universidade Federal do Oeste da Bahia, Bahia, Brasil
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Oliveira KRHM, Torres MLM, Kauffmann N, de Azevedo Ataíde BJ, de Souza Franco Mendes N, dos Anjos LM, dos Santos Borges R, Bahia CP, Leão LKR, da Conceição Fonseca Passos A, Herculano AM, de Jesus Oliveira Batista E. Euterpe oleracea fruit (Açai)-enriched diet suppresses the development of experimental cerebral malaria induced by Plasmodium berghei (ANKA) infection. BMC Complement Med Ther 2022; 22:11. [PMID: 35016657 PMCID: PMC8751313 DOI: 10.1186/s12906-021-03495-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Accepted: 12/07/2021] [Indexed: 11/21/2022] Open
Abstract
Background Cerebral malaria is one of the most severe complications attributed to protozoal infection by Plasmodium falciparum, gaining prominence in children mortality rates in endemic areas. This condition has a complex pathogenesis associated with behavioral, cognitive and motor sequels in humans and current antimalarial therapies have shown little effect in those aspects. Natural products with antioxidant and anti-inflammatory properties have become a valuable alternative therapeutic option in the treatment of distinct conditions. In this context, this study investigated the neuroprotective effect of Euterpe oleracea (açai) enriched diet during the development of experimental cerebral malaria induced by the inoculation of Swiss albino mice with Plasmodium berghei ANKA strain. Methods After Plasmodium infection, animals were maintained on a feeding with Euterpe oleracea enriched ration and parameters such as survival curve, parasitemia and body weight were routinely monitored. The present study has also evaluated the effect of açai-enriched diet on the blood-brain barrier leakage, histological alterations and neurocognitive impairments in mice developing cerebral malaria. Results Our results demonstrate that between 7th–19th day post infection the survival rate of the group treated with açai enriched ration was higher when compared with Plasmodium-infected mice in which 100% of mice died until the 11th days post-infection, demonstrating that açai diet has a protective effect on the survival of infected treated animals. The same was observed in the brain vascular extravasation, where Evans blue dye assays showed significantly less dye extravasation in the brains of Plasmodium-infected mice treated with açai enriched ration, demonstrating more preserved blood-brain barrier integrity. Açai-enriched diet also attenuate the histopathological alterations elicited by Plasmodium berghei infection. We also showed a decrease of the neurological impairments arising from the exposure of cerebral parenchyma in the group treated with açai diet, ameliorating motor and neuropsychiatric changes, analyzed through the SHIRPA protocol. Conclusion With these results, we conclude that the treatment with açai enriched ration decreased the mortality of infected animals, as well as protected the blood-brain barrier and the neurocognitive deficits in Plasmodium-infected animals.
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10
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Muema JM, Bargul JL, Mutunga JM, Obonyo MA, Asudi GO, Njeru SN. Neurotoxic Zanthoxylum chalybeum root constituents invoke mosquito larval growth retardation through ecdysteroidogenic CYP450s transcriptional perturbations. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2021; 178:104912. [PMID: 34446188 DOI: 10.1016/j.pestbp.2021.104912] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 06/24/2021] [Accepted: 06/27/2021] [Indexed: 06/13/2023]
Abstract
Intracellular effects exerted by phytochemicals eliciting insect growth-retarding responses during vector control intervention remain largely underexplored. We studied the effects of Zanthoxylum chalybeum Engl. (Rutaceae) (ZCE) root derivatives against malaria (Anopheles gambiae) and arbovirus vector (Aedes aegypti) larvae to decipher possible molecular targets. We report dose-dependent biphasic effects on larval response, with transient exposure to ZCE and its bioactive fraction (ZCFr.5) inhibiting acetylcholinesterase (AChE) activity, inducing larval lethality and growth retardation at sublethal doses. Half-maximal lethal concentrations (LC50) for ZCE against An. gambiae and Ae. aegypti larvae after 24-h exposure were 9.00 ppm and 12.26 ppm, respectively. The active fraction ZCFr.5 exerted LC50 of 1.58 ppm and 3.21 ppm for An. gambiae and Ae. aegypti larvae, respectively. Inhibition of AChE was potentially linked to larval toxicity afforded by 2-tridecanone, palmitic acid (hexadecanoic acid), linoleic acid ((Z,Z)-9,12-octadecadienoic acid), sesamin, β-caryophyllene among other compounds identified in the bioactive fraction. In addition, the phenotypic larval retardation induced by ZCE root constituents was exerted through transcriptional modulation of ecdysteroidogenic CYP450 genes. Collectively, these findings provide an explorative avenue for developing potential mosquito control agents from Z. chalybeum root constituents.
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Affiliation(s)
- Jackson M Muema
- Department of Biochemistry, Jomo Kenyatta University of Agriculture & Technology (JKUAT), Nairobi, Kenya; Molecular Biology and Bioinformatics Unit, International Centre of Insect Physiology & Ecology (icipe), Nairobi, Kenya; Department of Entomology, U.S Army Medical Research Directorate-Africa, Kenya (USAMRD-A/K), Kisumu, Kenya.
| | - Joel L Bargul
- Department of Biochemistry, Jomo Kenyatta University of Agriculture & Technology (JKUAT), Nairobi, Kenya; Molecular Biology and Bioinformatics Unit, International Centre of Insect Physiology & Ecology (icipe), Nairobi, Kenya
| | - James M Mutunga
- Department of Entomology, U.S Army Medical Research Directorate-Africa, Kenya (USAMRD-A/K), Kisumu, Kenya
| | - Meshack A Obonyo
- Department of Biochemistry & Molecular Biology, Egerton University, Egerton, Kenya
| | - George O Asudi
- Department of Biochemistry, Microbiology & Biotechnology, Kenyatta University, Nairobi, Kenya
| | - Sospeter N Njeru
- Centre for Traditional Medicine and Drug Research (CTMDR), Kenya Medical Research Institute (KEMRI), Nairobi, Kenya.
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11
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Konopka JK, Task D, Afify A, Raji J, Deibel K, Maguire S, Lawrence R, Potter CJ. Olfaction in Anopheles mosquitoes. Chem Senses 2021; 46:6246230. [PMID: 33885760 DOI: 10.1093/chemse/bjab021] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
As vectors of disease, mosquitoes are a global threat to human health. The Anopheles mosquito is the deadliest mosquito species as the insect vector of the malaria-causing parasite, which kills hundreds of thousands every year. These mosquitoes are reliant on their sense of smell (olfaction) to guide most of their behaviors, and a better understanding of Anopheles olfaction identifies opportunities for reducing the spread of malaria. This review takes a detailed look at Anopheles olfaction. We explore a range of topics from chemosensory receptors, olfactory neurons, and sensory appendages to behaviors guided by olfaction (including host-seeking, foraging, oviposition, and mating), to vector management strategies that target mosquito olfaction. We identify many research areas that remain to be addressed.
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Affiliation(s)
- Joanna K Konopka
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, 855 North Wolfe Street, 434 Rangos Building, Baltimore, 21205 MD, USA
| | - Darya Task
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, 855 North Wolfe Street, 434 Rangos Building, Baltimore, 21205 MD, USA
| | - Ali Afify
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, 855 North Wolfe Street, 434 Rangos Building, Baltimore, 21205 MD, USA
| | - Joshua Raji
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, 855 North Wolfe Street, 434 Rangos Building, Baltimore, 21205 MD, USA
| | - Katelynn Deibel
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, 855 North Wolfe Street, 434 Rangos Building, Baltimore, 21205 MD, USA
| | - Sarah Maguire
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, 855 North Wolfe Street, 434 Rangos Building, Baltimore, 21205 MD, USA
| | - Randy Lawrence
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, 855 North Wolfe Street, 434 Rangos Building, Baltimore, 21205 MD, USA
| | - Christopher J Potter
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, 855 North Wolfe Street, 434 Rangos Building, Baltimore, 21205 MD, USA
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12
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Milugo TK, Tchouassi DP, Kavishe RA, Dinglasan RR, Torto B. Derivatization increases mosquito larvicidal activity of the sesquiterpene lactone parthenin isolated from the invasive weed Parthenium hysterophorus. PEST MANAGEMENT SCIENCE 2021; 77:659-665. [PMID: 33034953 DOI: 10.1002/ps.6131] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Revised: 09/25/2020] [Accepted: 10/09/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND Extracts of the invasive weed Parthenium hysterophorus (Asteraceae) have been shown to possess larvicidal activity against a wide range of disease vectors. However, the phytochemicals responsible for the larvicidal activity from this plant remain unidentified. Here, we isolated the major sesquiterpene lactone, parthenin (1) from the plant and synthesized two derivatives [ethylene glycol (2) and azide (3) derivatives] targeting the α,β-unsaturated carbonyl group, previously known to account for its biological activity such as toxicity towards cells and microorganism. All three compounds were screened for larvicidal activity against the African malaria vector Anopheles gambiae. RESULTS The larval mortality of ethylene glycol derivative (2) and 2α-azidocoronopilin (3) were approximately two-four-fold higher than that of parthenin (1) and neem oil with LC50 values of 37 and 66 mg L-1 , respectively. Parthenin (1) and the positive control, neem oil, had comparable median lethal concentration (LC50 ) values of 154 and 121 mg L-1 , respectively. In assays with binary combinations of the three compounds, larvicidal activity followed the order: parthenin (1) + 2α-azidocoronopilin (3) (LC50 = 14 mg L-1 ) > parthenin (1) + ethylene glycol derivative (2) (LC50 = 109 mg L-1 ), > blend of 2α-azidocoronopilin (3) and ethylene glycol derivative (2) (LC50 = 200 mg L-1 ). CONCLUSION Structural modification of parthenin (1) through addition of hydroxyl groups increases its larvicidal effects. These findings advance the use of structural modification approach in the development of lead chemical molecules for potential exploitation in larval source management.
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Affiliation(s)
- Trizah K Milugo
- International Centre of Insect Physiology and Ecology (ICIPE), Nairobi, Kenya
- Department of Biochemistry and Molecular Biology, Kilimanjaro Christian Medical University College (KCMUCo), Moshi, Tanzania
| | - David P Tchouassi
- International Centre of Insect Physiology and Ecology (ICIPE), Nairobi, Kenya
| | - Reginald A Kavishe
- Department of Biochemistry and Molecular Biology, Kilimanjaro Christian Medical University College (KCMUCo), Moshi, Tanzania
| | - Rhoel R Dinglasan
- Emerging Pathogens Institute, Department of Infectious Diseases & Immunology, College of Veterinary Medicine, University of Florida, Gainesville, FL, USA
| | - Baldwyn Torto
- International Centre of Insect Physiology and Ecology (ICIPE), Nairobi, Kenya
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13
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Buxton M, Wasserman RJ, Nyamukondiwa C. Spatial Anopheles arabiensis (Diptera: Culicidae) insecticide resistance patterns across malaria-endemic regions of Botswana. Malar J 2020; 19:415. [PMID: 33213466 PMCID: PMC7678117 DOI: 10.1186/s12936-020-03487-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Accepted: 11/09/2020] [Indexed: 12/25/2022] Open
Abstract
Background Since the advent of the Green Revolution, pesticides have played an important role in the global management of invertebrate pests including vector mosquitoes. Despite optimal efficacy, insects often display insensitivity to synthetic insecticides owing to prolonged exposure that may select for resistance development. Such insecticide insensitivity may regress national and regional coordination in mosquito vector management and indeed malaria control. In Botswana, prolonged use of synthetic insecticides against malaria vectors have been practiced without monitoring of targeted mosquito species susceptibility status. Methods Here, susceptibility status of a malaria vector (Anopheles arabiensis), was assessed against World Health Organization-recommended insecticides, across three malaria endemic districts. Adult virgin female mosquitoes (2–5 days old) emerging from wild-collected larvae were exposed to standardized insecticide-impregnated papers with discriminating doses. Results The results showed resistance dynamics were variable in space, presumably as a result of spatial differences in insecticide use across malaria endemic districts and the types of insecticides used in the country. Overall, there was a reduced susceptibility of An. arabiensis for the pyrethroid lambda-cyhalothrin and for dichloro diphenyl trichloroethane [DDT], which have similar modes of action and have been used in the country for many years. The Okavango district exhibited the greatest reduction in susceptibility, followed by Ngamiland and then Bobirwa, reflective of national intervention strategy spraying intensities. Vector mosquitoes were, however, highly susceptible to carbamates and organophosphates irrespective of region. Conclusions These results provide important findings of vector susceptibility to insecticides recommended for vector control. The results highlight the need to implement insecticide application regimes that more effectively including regionally integrated resistance management strategies for effective malaria control and elimination.
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Affiliation(s)
- Mmabaledi Buxton
- Department of Biological Sciences and Biotechnology, Botswana International University of Science and Technology, Palapye, Botswana
| | - Ryan J Wasserman
- Department of Biological Sciences and Biotechnology, Botswana International University of Science and Technology, Palapye, Botswana.,Department of Zoology and Entomology, Rhodes University, Makhanda, 6140, South Africa
| | - Casper Nyamukondiwa
- Department of Biological Sciences and Biotechnology, Botswana International University of Science and Technology, Palapye, Botswana.
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14
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Buxton M, Machekano H, Gotcha N, Nyamukondiwa C, Wasserman RJ. Are Vulnerable Communities Thoroughly Informed on Mosquito Bio-Ecology and Burden? INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:ijerph17218196. [PMID: 33171954 PMCID: PMC7672552 DOI: 10.3390/ijerph17218196] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Revised: 09/24/2020] [Accepted: 09/25/2020] [Indexed: 11/25/2022]
Abstract
Mosquitoes account for a significant burden of morbidity and mortality globally. Despite evidence of (1) imminent anthropogenic climate and environmental changes, (2) vector-pathogen spatio-temporal dynamics and (3) emerging and re-emerging mosquito borne infections, public knowledge on mosquito bio-ecology remain scant. In particular, knowledge, attitude and practices (KAPs) on mosquitoes are often neglected despite otherwise expensive remedial efforts against consequent infections and other indirect effects associated with disease burden. To gather baseline KAPs that identify gaps for optimising vector-borne disease control, we surveyed communities across endemic and non-endemic malaria sub-districts (Botswana). The study revealed limited knowledge of mosquitoes and their infections uniformly across endemic and non-endemic areas. In addition, a significant proportion of respondents were concerned about mosquito burdens, although their level of personal, indoor and environmental protection practices varied significantly across sub-districts. Given the limited knowledge displayed by the communities, this study facilitates bridging KAP gaps to minimise disease burdens by strengthening public education. Furthermore, it provides a baseline for future studies in mosquito bio-ecology and desirable control practices across differential spheres of the rural–urban lifestyle, with implications for enhanced livelihoods as a consequence of improved public health.
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15
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Bokore GE, Ouma P, Onyango PO, Bukhari T, Fillinger U. A cross-sectional observational study investigating the association between sedges (swamp grasses, Cyperaceae) and the prevalence of immature malaria vectors in aquatic habitats along the shore of Lake Victoria, western Kenya. F1000Res 2020; 9:1032. [PMID: 33093949 PMCID: PMC7551511 DOI: 10.12688/f1000research.25673.2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/24/2020] [Indexed: 12/01/2022] Open
Abstract
Background: Strategies that involve manipulations of the odour-orientation of gravid malaria vectors could lead to novel attract-and-kill interventions. Recent work has highlighted the potential involvement of graminoid plants in luring vectors to oviposition sites. This study aimed to analyse the association between water-indicating graminoid plants (Cyperaceae, sedges), other abiotic and biotic factors and the presence and abundance of early instar
Anopheles larvae in aquatic habitats as a proxy indicator for oviposition. Methods: A cross-sectional survey of 110 aquatic habitats along the shores of Lake Victoria was done during the rainy season. Habitats were sampled for mosquito larvae using the sweep-net method and habitat characteristics recorded. Results:
Anopheles arabiensis was the dominant species identified from aquatic habitats. Larvae of the secondary malaria vectors such as
Anopheles coustani, An. rufipes and
An. maculipalpis were found only in habitats covered with graminoids, whereas
An. arabiensis, An. ziemanni and
An. pharoensis were found in both habitats with and without graminoid plants. The hypothesis that sedges might be positively associated with the presence and abundance of early instar
Anopheles larvae could not be confirmed. The dominant graminoid plants in the habitats were
Panicum repens,
Cynodon dactylon in the Poaceae family and
Cyperus rotundus in the Cyperaceae family. All of these habitats supported abundant immature vector populations. The presence of early instar larvae was significantly and positively associated with swamp habitat types (OR=22, 95% CI=6-86, P<0.001) and abundance of late
Anopheles larvae (OR=359, CI=33-3941, P<0.001), and negatively associated with the presence of tadpoles (OR=0.1, CI=0.0.01-0.5, P=0.008). Conclusions: Early instar malaria vectors were abundant in habitats densely vegetated with graminoid plants in the study area but no specific preference could be detected for any species or family. In search for oviposition cues, it might be useful to screen for chemical volatiles released from all dominant plant species.
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Affiliation(s)
- Getachew E Bokore
- International Centre of Insect Physiology and Ecology (icipe), P.O. Box 30772-00100, Nairobi, Kenya.,School of Physical and Biological Sciences, Department of Zoology, Maseno University, P.O. Box 333 - 40105, Maseno, Kenya.,Public Health Entomology Team, Ethiopian Public Health Institute, P.O. Box 1242, Addis Ababa, Ethiopia
| | - Paul Ouma
- International Centre of Insect Physiology and Ecology (icipe), P.O. Box 30772-00100, Nairobi, Kenya
| | - Patrick O Onyango
- School of Physical and Biological Sciences, Department of Zoology, Maseno University, P.O. Box 333 - 40105, Maseno, Kenya
| | - Tullu Bukhari
- International Centre of Insect Physiology and Ecology (icipe), P.O. Box 30772-00100, Nairobi, Kenya.,School of Physical and Biological Sciences, Department of Zoology, Maseno University, P.O. Box 333 - 40105, Maseno, Kenya
| | - Ulrike Fillinger
- International Centre of Insect Physiology and Ecology (icipe), P.O. Box 30772-00100, Nairobi, Kenya
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16
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Senthil-Nathan S. A Review of Resistance Mechanisms of Synthetic Insecticides and Botanicals, Phytochemicals, and Essential Oils as Alternative Larvicidal Agents Against Mosquitoes. Front Physiol 2020; 10:1591. [PMID: 32158396 PMCID: PMC7052130 DOI: 10.3389/fphys.2019.01591] [Citation(s) in RCA: 67] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 12/19/2019] [Indexed: 12/16/2022] Open
Abstract
Mosquitoes are a serious threat to the society, acting as vector to several dreadful diseases. Mosquito management programes profoundly depend on the routine of chemical insecticides that subsequently lead to the expansion of resistance midst the vectors, along with other problems such as environmental pollution, bio magnification, and adversely affecting the quality of public and animal health, worldwide. The worldwide risk of insect vector transmitted diseases, with their associated illness and mortality, emphasizes the need for effective mosquitocides. Hence there is an immediate necessity to develop new eco-friendly pesticides. As a result, numerous investigators have worked on the development of eco-friendly effective mosquitocidal compounds of plant origin. These products have a cumulative advantage of being cost-effective, environmentally benign, biodegradable, and safe to non-target organisms. This review aims at describing the current state of research on behavioral, physiological, and biochemical effects of plant derived compounds with larvicidal effects on mosquitoes. The mode of physiological and biochemical action of known compounds derived from various plant families as well as the potential of plant secondary metabolites, plant extracts, and also the essential oils (EO), as mosquitocidal agents are discussed. This review clearly indicates that the application of vegetal-based compounds as mosquito control proxies can serve as alternative biocontrol methods in mosquito management programes.
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Affiliation(s)
- Sengottayan Senthil-Nathan
- Division of Biopesticides and Environmental Toxicology, Sri Paramakalyani Centre for Excellence in Environmental Sciences, Manonmaniam Sundaranar University, Tirunelveli, India
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Djamouko-Djonkam L, Mounchili-Ndam S, Kala-Chouakeu N, Nana-Ndjangwo SM, Kopya E, Sonhafouo-Chiana N, Talipouo A, Ngadjeu CS, Doumbe-Belisse P, Bamou R, Toto JC, Tchuinkam T, Wondji CS, Antonio-Nkondjio C. Spatial distribution of Anopheles gambiae sensu lato larvae in the urban environment of Yaoundé, Cameroon. Infect Dis Poverty 2019; 8:84. [PMID: 31594541 PMCID: PMC6784347 DOI: 10.1186/s40249-019-0597-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Accepted: 09/10/2019] [Indexed: 11/23/2022] Open
Abstract
Background The rapid and unplanned urbanization of African cities is considered to increase the risk of urban malaria transmission. The present study objective was to assess factors influencing the spatio-temporal distribution of Anopheles gambiae s.l. larvae in the city of Yaoundé, Cameroon. Methods All water bodies were checked once every 2 months for the presence of mosquito larvae from March 2017 to May 2018 in 32 districts of Yaoundé. Physico-chemical characteristics including the size, depth, turbidity, pH, temperature, conductivity, sulfates, organophosphates, hydrogen peroxide (H2O2), conductivity, iron and calcium were recorded and analyzed according to anopheline larvae presence or absence. High resolution satellite images from landsat sentinel Enhanced Thematic Mapper were used for spatial mapping of both field and environmental variables. Bivariate and multivariate logistic regression models were used to identify variables closely associated with anopheline larvae distribution. Results A total of 18 696 aquatic habitats were checked and only 2942 sites (15.7%) contained anopheline larvae. A high number of sites with anopheline larvae (≥ 69%) presented late instar larvae (L3, L4 and pupae). Anopheline mosquito larvae were sampled from a variety of breeding sites including puddles (51.6%), tire prints (12.9%), wells (11.7%) and drains (11.3%). Bivariate logistic regression analyses associated anopheline larvae presence with the absence of predators, absence of algae, absence of vegetation and depth of less than 1 m. Conductivity, turbidity, organophosphates, H2O2 and temperature were significantly high in breeding sites with anopheline larvae than in breeding sites without these larvae (P < 0.1). Anopheline species collected included An. coluzzii (91.1%) and An. gambiae s.s. (8.9%). GIS mapping indicated a heterogeneous distribution of anopheline breeding habitats in the city of Yaoundé. Land cover analysis indicated high variability of the city of Yaoundé’s landscape. Conclusions The data confirms adaptation of An. gambiae s.l. to the urban domain in the city of Yaoundé and calls for urgent actions to improve malaria vector control.
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Affiliation(s)
- Landre Djamouko-Djonkam
- Malaria Research Laboratory, Organization for the fight against Endemic diseases in Central Africa (OCEAC), P.O. Box 288, Yaoundé, Cameroon.,Vector Borne Infectious Disease Unit of the Laboratory of Applied Biology and Ecology (VBID-LABEA), Department of Animal Biology, Faculty of Science, University of Dschang, P.O. Box 067, Dschang, Cameroon
| | - Souleman Mounchili-Ndam
- Malaria Research Laboratory, Organization for the fight against Endemic diseases in Central Africa (OCEAC), P.O. Box 288, Yaoundé, Cameroon.,Faculty of Science, University of Yaounde I, P.O. Box 337, Yaounde, Cameroon
| | - Nelly Kala-Chouakeu
- Malaria Research Laboratory, Organization for the fight against Endemic diseases in Central Africa (OCEAC), P.O. Box 288, Yaoundé, Cameroon.,Vector Borne Infectious Disease Unit of the Laboratory of Applied Biology and Ecology (VBID-LABEA), Department of Animal Biology, Faculty of Science, University of Dschang, P.O. Box 067, Dschang, Cameroon
| | - Stella Mariette Nana-Ndjangwo
- Malaria Research Laboratory, Organization for the fight against Endemic diseases in Central Africa (OCEAC), P.O. Box 288, Yaoundé, Cameroon.,Faculty of Science, University of Yaounde I, P.O. Box 337, Yaounde, Cameroon
| | - Edmond Kopya
- Malaria Research Laboratory, Organization for the fight against Endemic diseases in Central Africa (OCEAC), P.O. Box 288, Yaoundé, Cameroon.,Faculty of Science, University of Yaounde I, P.O. Box 337, Yaounde, Cameroon
| | - Nadége Sonhafouo-Chiana
- Malaria Research Laboratory, Organization for the fight against Endemic diseases in Central Africa (OCEAC), P.O. Box 288, Yaoundé, Cameroon.,Faculty of Health Sciences University of Buea, P.O. Box 63, Buea, Cameroon
| | - Abdou Talipouo
- Malaria Research Laboratory, Organization for the fight against Endemic diseases in Central Africa (OCEAC), P.O. Box 288, Yaoundé, Cameroon.,Faculty of Science, University of Yaounde I, P.O. Box 337, Yaounde, Cameroon
| | - Carmene Sandra Ngadjeu
- Malaria Research Laboratory, Organization for the fight against Endemic diseases in Central Africa (OCEAC), P.O. Box 288, Yaoundé, Cameroon.,Faculty of Science, University of Yaounde I, P.O. Box 337, Yaounde, Cameroon
| | - Patricia Doumbe-Belisse
- Malaria Research Laboratory, Organization for the fight against Endemic diseases in Central Africa (OCEAC), P.O. Box 288, Yaoundé, Cameroon.,Faculty of Science, University of Yaounde I, P.O. Box 337, Yaounde, Cameroon
| | - Roland Bamou
- Malaria Research Laboratory, Organization for the fight against Endemic diseases in Central Africa (OCEAC), P.O. Box 288, Yaoundé, Cameroon.,Vector Borne Infectious Disease Unit of the Laboratory of Applied Biology and Ecology (VBID-LABEA), Department of Animal Biology, Faculty of Science, University of Dschang, P.O. Box 067, Dschang, Cameroon
| | - Jean Claude Toto
- Malaria Research Laboratory, Organization for the fight against Endemic diseases in Central Africa (OCEAC), P.O. Box 288, Yaoundé, Cameroon
| | - Timoléon Tchuinkam
- Vector Borne Infectious Disease Unit of the Laboratory of Applied Biology and Ecology (VBID-LABEA), Department of Animal Biology, Faculty of Science, University of Dschang, P.O. Box 067, Dschang, Cameroon
| | | | - Christophe Antonio-Nkondjio
- Malaria Research Laboratory, Organization for the fight against Endemic diseases in Central Africa (OCEAC), P.O. Box 288, Yaoundé, Cameroon. .,Vector Biology Liverpool School of Tropical medicine Pembroke Place, Liverpool, L3 5QA, UK.
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18
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Kilian N, Choi JY, Voelker DR, Ben Mamoun C. Role of phospholipid synthesis in the development and differentiation of malaria parasites in the blood. J Biol Chem 2018; 293:17308-17316. [PMID: 30287688 DOI: 10.1074/jbc.r118.003213] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The life cycle of malaria parasites in both their mammalian host and mosquito vector consists of multiple developmental stages that ensure proper replication and progeny survival. The transition between these stages is fueled by nutrients scavenged from the host and fed into specialized metabolic pathways of the parasite. One such pathway is used by Plasmodium falciparum, which causes the most severe form of human malaria, to synthesize its major phospholipids, phosphatidylcholine, phosphatidylethanolamine, and phosphatidylserine. Much is known about the enzymes involved in the synthesis of these phospholipids, and recent advances in genetic engineering, single-cell RNA-Seq analyses, and drug screening have provided new perspectives on the importance of some of these enzymes in parasite development and sexual differentiation and have identified targets for the development of new antimalarial drugs. This Minireview focuses on two phospholipid biosynthesis enzymes of P. falciparum that catalyze phosphoethanolamine transmethylation (PfPMT) and phosphatidylserine decarboxylation (PfPSD) during the blood stages of the parasite. We also discuss our current understanding of the biochemical, structural, and biological functions of these enzymes and highlight efforts to use them as antimalarial drug targets.
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Affiliation(s)
- Nicole Kilian
- From the Department of Internal Medicine, Section of Infectious Diseases, Yale School of Medicine, New Haven, Connecticut 06520 and
| | - Jae-Yeon Choi
- the Basic Science Section, Department of Medicine, National Jewish Health, Denver, Colorado 80206
| | - Dennis R Voelker
- the Basic Science Section, Department of Medicine, National Jewish Health, Denver, Colorado 80206
| | - Choukri Ben Mamoun
- From the Department of Internal Medicine, Section of Infectious Diseases, Yale School of Medicine, New Haven, Connecticut 06520 and
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19
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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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20
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Antonio-Nkondjio C, Sandjo NN, Awono-Ambene P, Wondji CS. Implementing a larviciding efficacy or effectiveness control intervention against malaria vectors: key parameters for success. Parasit Vectors 2018; 11:57. [PMID: 29368633 PMCID: PMC5784718 DOI: 10.1186/s13071-018-2627-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Accepted: 01/08/2018] [Indexed: 11/21/2022] Open
Abstract
During the last decade, scale-up of vector control tools such as long-lasting insecticidal nets (LLINs) and indoor residual spraying (IRS) contributed to the reduction of malaria morbidity and mortality across the continent. Because these first line interventions are now affected by many challenges such as insecticide resistance, change in vector feeding and biting behaviour, outdoor malaria transmission and adaptation of mosquito to polluted environments, the World Health Organization recommends the use of integrated control approaches to improve, control and elimination of malaria. Larviciding is one of these approaches which, if well implemented, could help control malaria in areas where this intervention is suitable. Unfortunately, important knowledge gaps remain in its successful application. The present review summarises key parameters that should be considered when implementing larviciding efficacy or effectiveness trials.
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Affiliation(s)
- Christophe Antonio-Nkondjio
- Laboratoire de Recherche sur le Paludisme, Organisation de Coordination pour la lutte Contre les Endémies en Afrique Centrale (OCEAC), P.O. Box 288, Yaoundé, Cameroon. .,Vector Group Liverpool School of Tropical medicine Pembroke Place, Liverpool, L3 5QA, UK.
| | - Nino Ndjondo Sandjo
- Montreal University School of Public Health, 7101 Av du Parc, Montréal, QC, H3N, Canada.,SPatial HEalth REsearch Lab (SPHERE LAB), Montreal University Hospital Research Center (CRCHUM), 900 Rue Saint-Denis, Montréal, QC, H2X 0A9, Canada
| | - Parfait Awono-Ambene
- Laboratoire de Recherche sur le Paludisme, Organisation de Coordination pour la lutte Contre les Endémies en Afrique Centrale (OCEAC), P.O. Box 288, Yaoundé, Cameroon
| | - Charles S Wondji
- Vector Group Liverpool School of Tropical medicine Pembroke Place, Liverpool, L3 5QA, UK
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21
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Bismuth Oxyiodide Nanoflakes Showed Toxicity Against the Malaria Vector Anopheles stephensi and In Vivo Antiplasmodial Activity. J CLUST SCI 2018. [DOI: 10.1007/s10876-018-1332-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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22
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Mbatchou VC, Tchouassi DP, Dickson RA, Annan K, Mensah AY, Amponsah IK, Jacob JW, Cheseto X, Habtemariam S, Torto B. Mosquito larvicidal activity of Cassia tora seed extract and its key anthraquinones aurantio-obtusin and obtusin. Parasit Vectors 2017; 10:562. [PMID: 29126433 PMCID: PMC5681828 DOI: 10.1186/s13071-017-2512-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Accepted: 10/31/2017] [Indexed: 12/22/2022] Open
Abstract
Background The edible and medicinal leguminous plant Cassia tora L. (Fabaceae) is known to possess insecticidal properties against a wide range of plant-feeding insects. However, the bioactivity of extracts of this plant and their constituents against vectors of medical importance has been largely unexplored. We investigated the mosquito larvicidal activity of the seed extract and its major anthraquinones against larvae of the African malaria vector Anopheles gambiae (s.s.). Methods Third-fourth instar larval mortality was observed after 24, 48, 72 and 96 h of exposure to varying doses of the extracts, and two anthraquinones isolates identified using liquid chromatography- quadrupole time of flight mass spectrometry (LC-QtoF-MS). The mosquito larval mortality was evaluated relative to the natural insecticide azadirachtin. Results Fractionation of the crude extract decreased mosquito larvicidal activity, however, larvicidal activity increased with increasing dose of the treatment and exposure time. The known anthraquinones aurantio-obtusin and obtusin were identified as key larvicidal compounds. Aurantio-obtusin and obtusin, exhibited similar toxicity to larvae of A. gambiae (s.s.) with LD50 values of 10 and 10.2 ppm, respectively. However, the two anthraquinones were four- and ~ six-fold less potent than that of the crude seed extract and azadirachtin, which had comparable LD50 values of 2.5 and 1.7 ppm, respectively. Conclusion Both aurantio-obtusin and obtusin showed mosquito larvicidal activity which were comparable to their respective fractions although they were less potent relative to the crude extract and azadirachtin. Further studies need to be conducted on C. tora for its exploitation as a potential eco-friendly tool in mosquito larval source reduction.
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Affiliation(s)
- Valentine C Mbatchou
- Department of Applied Chemistry and Biochemistry, University for Development Studies, Navrongo Campus, Navrongo, Ghana.,Department of Pharmacognosy, Faculty of Pharmacy and Pharmaceutical Sciences, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - David P Tchouassi
- International Centre of Insect Physiology and Ecology, P.O. Box 30772, Nairobi, Kenya
| | - Rita A Dickson
- Department of Pharmacognosy, Faculty of Pharmacy and Pharmaceutical Sciences, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Kofi Annan
- Department of Pharmacognosy, Faculty of Pharmacy and Pharmaceutical Sciences, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Abraham Y Mensah
- Department of Pharmacognosy, Faculty of Pharmacy and Pharmaceutical Sciences, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Isaac K Amponsah
- Department of Pharmacognosy, Faculty of Pharmacy and Pharmaceutical Sciences, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Julia W Jacob
- International Centre of Insect Physiology and Ecology, P.O. Box 30772, Nairobi, Kenya
| | - Xavier Cheseto
- International Centre of Insect Physiology and Ecology, P.O. Box 30772, Nairobi, Kenya
| | - Solomon Habtemariam
- Pharmacognosy Research Laboratories and Herbal Analysis Services UK, University of Greenwich, Chatham-Maritime, Kent, ME4 4TB, UK
| | - Baldwyn Torto
- International Centre of Insect Physiology and Ecology, P.O. Box 30772, Nairobi, Kenya. .,Department of Zoology and Entomology, University of Pretoria, Pretoria, South Africa.
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