Back to Search
Start Over
Transmission blocking activity of Azadirachta indica and Guiera senegalensis extracts on the sporogonic development of Plasmodium falciparum field isolates in Anopheles coluzzii mosquitoes
- Source :
- Parasites & Vectors; Vol 7, Parasites & Vectors
- Publication Year :
- 2014
-
Abstract
- Background: Targeting the stages of the malaria parasites responsible for transmission from the human host to the mosquito vector is a key pharmacological strategy for malaria control. Research efforts to identify compounds that are active against these stages have significantly increased in recent years. However, at present, only two drugs are available, namely primaquine and artesunate, which reportedly act on late stage gametocytes. Methods: In this study, we assessed the antiplasmodial effects of 5 extracts obtained from the neem tree Azadirachta indica and Guiera senegalensis against the early vector stages of Plasmodium falciparum, using field isolates. In an ex vivo assay gametocytaemic blood was supplemented with the plant extracts and offered to Anopheles coluzzii females by membrane feeding. Transmission blocking activity was evaluated by assessing oocyst prevalence and density on the mosquito midguts. Results: Initial screening of the 5 plant extracts at 250 ppm revealed transmission blocking activity in two neem preparations. Up to a concentration of 70 ppm the commercial extract NeemAzal (R) completely blocked transmission and at 60 ppm mosquitoes of 4 out of 5 replicate groups remained uninfected. Mosquitoes fed on the ethyl acetate phase of neem leaves at 250 ppm showed a reduction in oocyst prevalence of 59.0% (CI95 12.0 -79.0; p < 10(-4)) and in oocyst density of 90.5% (CI95 86.0 -93.5; p < 10(-4)), while the ethanol extract from the same plant part did not exhibit any activity. No evidence of transmission blocking activity was found using G. senegalensis ethyl acetate extract from stem galls. Conclusions: The results of this study highlight the potential of antimalarial plants for the discovery of novel transmission blocking molecules, and open up the potential of developing standardized transmission blocking herbal formulations as malaria control tools to complement currently used antimalarial drugs and combination treatments.
- Subjects :
- ANTIMALARIAL-DRUGS
Primaquine
PARASITES
Mycology & Parasitology
Gametocytes
Toxicology
chemistry.chemical_compound
0302 clinical medicine
1108 Medical Microbiology
SEXUAL DEVELOPMENT
0303 health sciences
MALARIA TRANSMISSION
Traditional medicine
Anopheles
Azadirachta
Sporogonic stages
3. Good health
PRIMAQUINE
Infectious Diseases
Child, Preschool
Female
Life Sciences & Biomedicine
medicine.drug
ARTESUNATE
Plasmodium falciparum
030231 tropical medicine
INHIBITION
Biology
1117 Public Health and Health Services
03 medical and health sciences
Combretaceae
Tropical Medicine
parasitic diseases
medicine
Gametocyte
Animals
Humans
PLANTS
030304 developmental biology
Science & Technology
Plant Extracts
Research
Plant extracts
IN-VITRO
biology.organism_classification
medicine.disease
Transmission-blocking drugs
Guiera senegalensis
NEEM EXTRACT
chemistry
Artesunate
Parasitology
Malaria
Subjects
Details
- Language :
- English
- Database :
- OpenAIRE
- Journal :
- Parasites & Vectors; Vol 7, Parasites & Vectors
- Accession number :
- edsair.doi.dedup.....dcb9919ea8c72a82d0894a60de9faafa