In vivo anti-plasmodial activities and toxic impacts of lime extract of a combination of Picralima nitida, Alstonia boonei and Gongronema latifolium in mice infected with Chloroquine-sensitive Plasmodium berghei.

Background: Lime extracts of powdered combination of seeds of Picralima nitida, stem bark of Alstonia boonei and leaves of Gongronema latifolium is a common remedy used in the treatment of malaria in South Western Nigeria.Objective: To determine the antiplasmodial activities of the combined herbal extracts and its impact on the haematological, hepatological and renological parameters in mice.Methods: The 4-day suppressive and curative tests were used to assess the antiplasmodial activities of the extract in mice infected with chloroquine-sensitive Plasmodium berghei at concentration of 200mg/kg, 400mg/kg and 800mg/kg body weight. The haematological parameters including red blood cells, white blood cells, packed cell volume and haemoglobin count were analysed with an auto analyser. The activities of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP) were determined, while urea, protein and creatinine were analysed by standard procedural methods.Results: The 4-day suppressive test revealed that the test extract achieved percentage suppression of 39.0%, 41.6% and 54.68% for the 200mg/kg, 400mg/kg and 800mg/kg concentration respectively. Additionally, the curative test achieved a high percentage suppression of 80.97%, 83.84% and 86.16% at the 200mg/kg, 400mg/kg and 800mg/kg concentration respectively. The extracts did not induce significant change on haematological parameters (P>0.05), while significant elevation in the values of the ALT and AST (P<0.05) was observed and elevation of creatinine (P<0.05) at 800mg/kg.Conclusions: The results support the traditional use of the herbal combination in the treatment of malaria, however the liver cells were impacted by the extracts in bioassay conducted with mice.Keywords: In vivo anti-plasmodial lime extract, Picralima nitida, Alstonia boonei, Gongronema latifolium, mice infected with chloroquine-sensitive plasmodium berghei

In vivo anti-plasmodial activities and toxic impacts of lime extract of a combination of Picralima nitida , Alstonia boonei and Gongronema latifolium in mice infected with Chloroquine-sensitive Plasmodium berghei.

Background: Lime extracts of powdered combination of seeds of Picralima nitida , stem bark of Alstonia boonei and leaves of Gongronema latifolium is a common remedy used in the treatment of malaria in South Western Nigeria. Objective: To determine the antiplasmodial activities of the combined herbal extracts and its impact on the haematological, hepatological and renological parameters in mice. Methods: The 4-day suppressive and curative tests were used to assess the antiplasmodial activities of the extract in mice infected with chloroquine-sensitive Plasmodium berghei at concentration of 200mg/kg, 400mg/kg and 800mg/kg body weight. The haematological parameters including red blood cells, white blood cells, packed cell volume and haemoglobin count were analysed with an auto analyser. The activities of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP) were determined, while urea, protein and creatinine were analysed by standard procedural methods. Results: The 4-day suppressive test revealed that the test extract achieved percentage suppression of 39.0%, 41.6% and 54.68% for the 200mg/kg, 400mg/kg and 800mg/kg concentration respectively. Additionally, the curative test achieved a high percentage suppression of 80.97%, 83.84% and 86.16% at the 200mg/kg, 400mg/kg and 800mg/kg concentration respectively. The extracts did not induce significant change on haematological parameters (P>0.05), while significant elevation in the values of the ALT and AST (P<0.05) was observed and elevation of creatinine (P<0.05) at 800mg/kg. Conclusions: The results support the traditional use of the herbal combination in the treatment of malaria, however the liver cells were impacted by the extracts in bioassay conducted with mice

High cases of submicroscopic Plasmodium falciparum infections in a suburban population of Lagos, Nigeria.

BACKGROUND: Asymptomatic malaria parasites are significant sources of infections for onward malaria transmission. Conventional tools for malaria diagnosis such as microscopy and rapid diagnostic test kits (RDT) have relatively low sensitivity, hence the need for alternative tools for active screening of such low-density infections. METHODS: This study tested var acidic terminal sequence-based (varATS) quantitative polymerase chain reaction (qPCR) for screening asymptomatic Plasmodium falciparum infections among dwellers of a sub-urban community in Lagos, Nigeria. Clinically healthy participants were screened for malaria using microscopy, RDT and varATS qPCR techniques. Participants were stratified into three age groups: 1-5, 6-14 and > 14 years old. RESULTS: Of the 316 participants screened for asymptomatic malaria infection, 78 (24.68%) were positive by microscopy, 99 (31.33%) were positive by RDT and 112 (35.44%) by varATS qPCR. Participants aged 6-14 years had the highest prevalence of asymptomatic malaria, with geometric means of ~ 116 parasites/µL and ~ 6689 parasites/µL as detected by microscopy and varATS, respectively. CONCLUSION: This study has revealed high prevalence of asymptomatic malaria in the study population, with varATS detecting additional sub-microscopic infections. The highest concentration of asymptomatic malaria was observed among school-age children between 6 and 14 years old. A large-scale screening to identify other potential hotspots of asymptomatic parasites in the country is recommended

Evidence of carbamate resistance in urban populations of <it>Anopheles gambiae s.s.</it> mosquitoes resistant to DDT and deltamethrin insecticides in Lagos, South-Western Nigeria

<p>Abstract</p> <p>Background</p> <p>Resistance monitoring is essential in ensuring the success of insecticide based vector control programmes. This study was carried out to assess the susceptibility status of urban populations of <it>Anopheles gambiae</it> to carbamate insecticide being considered for vector control in mosquito populations previously reported to be resistant to DDT and permethrin.</p> <p>Methods</p> <p>Two – three day old adult female <it>Anopheles</it> mosquitoes reared from larval collections in 11 study sites from Local Government Areas of Lagos were exposed to test papers impregnated with DDT 4%, deltamethrin 0.05% and propoxur 0.1% insecticides. Additional tests were carried out to determine the susceptibility status of the <it>Anopheles gambiae</it> population to bendiocarb insecticide. Members of the <it>A. gambiae complex</it>, the molecular forms, were identified by PCR assays. The involvement of metabolic enzymes in carbamate resistance was assessed using Piperonyl butoxide (PBO) synergist assays. The presence of kdr-<it>w/e</it> and ace-1R point mutations responsible for DDT-pyrethroid and carbamate resistance mechanisms was also investigated by PCR.</p> <p>Results</p> <p>Propoxur resistance was found in 10 out of the 11 study sites. Resistance to three classes of insecticides was observed in five urban localities. Mortality rates in mosquitoes exposed to deltamethrin and propoxur did not show any significant difference (P > 0.05) but was significantly higher (P < 0.05) in populations exposed to DDT. All mosquitoes tested were identified as <it>A. gambiae s.s</it> (M form). The <it>kdr -w</it> point mutation at allelic frequencies between 45%-77% was identified as one of the resistant mechanisms responsible for DDT and pyrethroid resistance. <it>Ace-1R</it> point mutation was absent in the carbamate resistant population. However, the possible involvement of metabolic resistance was confirmed by synergistic assays conducted.</p> <p>Conclusion</p> <p>Evidence of carbamate resistance in <it>A. gambiae</it> populations already harbouring resistance to DDT and permethrin is a clear indication that calls for the implementation of insecticide resistance management strategies to combat the multiple resistance identified.</p