Clinical Probe of Cyp2C8*2 Mutants in a Malaria Hyperendemic Zone: Evidence from North-Central, Nigeria.

BACKGROUND: A tremendous level of success has been achieved since the introduction of chloroquine and the combination of amodiaquine and artemisinin for the treatment of both complicated and uncomplicated malaria infections in sub-Saharan Africa. However, the recent discovery of drug resistant strains of Plasmodium falciparum (P.f.) and the ability of the parasite to ingest CYP2C8 into its digestive vacuole is of great public health concern. This study probes the occurrence of CYP2C8*2 allelic mutant amongst malaria patients in North-Central Nigeria. METHODS: Three hundred and eighty five (385) unrelated study participants were screened for current malaria episodes using routine microscopy and/or rapid diagnostic test strips (RDTs). Chelex extraction method was used for single nucleotide polymorphisms (SNPs) and identification of CYP2C8*2 (805A > T) variant respectively. Wild-type (A) and the defective allele (T) were differentiated with the use of Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP). The results obtained were further validated with Sanger sequencing of a few samples and thereafter, the genotype data were statistically processed. All alleles obtained were in Hardy Weinberg equilibrium. RESULTS: Out of the 385 participants (45.5% Male and 54.5% Female) genotyped for SNPs, 75 (19.5%) had the autosomal recessive mutant trait. Occurrence of mutant traits was gender and ethnic independent (p > 0.05). Yoruba ethnic group recorded a reduction in proportion of genotypic defective CYP2C8*2 allele (T) (1 in every 8 persons) with a carrier percentage of 13.3% compared with Hausa (26.62%); Igbo (25.37%) and other minority ethnic groups (17.6%). CONCLUSIONS: A remarkable inter-ethnic differences in autosomal recessive CYP2C8*2 allele was observed. By implication, there is a gradual incursion of genetic drift for poor CQ and AQ-Artemisinin metabolizers among the inhabitants.

Association Between Farming Activities and Plasmodium falciparum Transmission in Rural Communities in Nigeria.

BACKGROUND: The connection between malaria-associated morbidities and farming activities has not been succinctly reported. This study aimed to address the connectivity between farming activities and malaria transmission. METHODS: The study took place in the agricultural setting of Nigeria Edu local government (9° N, 4.9° E) between March 2016 and December 2018. A pre-tested structured questionnaire was administered to obtain information on their occupation and malaria infection. Infection status was confirmed with blood film and microscopic diagnosis of Plasmodium falciparum was based on the presence of ring form or any other blood stages. Individuals who are either critically ill or lived in the community less than 3 months were excluded from the study. RESULTS: Of the 341 volunteers, 58.1% (52.9% in Shigo and 61.4% in Sista) were infected (parasitaemia density of 1243.7 parasites/µL blood). The prevalence and intensity of infection were higher among farmers (71.3%, 1922.9 parasites/µL blood, P = 0.005), particularly among rice farmers (2991.6 parasites/µL blood) compared to non-farmer participants. The occurrence and parasite density follow the same pattern for sex and age (P < 0.05). Children in the age of 6 to 10 years (AOR: 2.168, CI: 1.63-2.19) and ≥ 11 years (AOR: 3.750, CI: 2.85-3.80) groups were two-and four-fold more likely to be infected with malaria. The analysis revealed that the proximity of bush and stagnant water to the farmer (73.9%, AOR: 3.242, CI: 2.57-3.61) and non-farmer (38.1%, AOR: 1.362, CI: 1.25-1.41) habitations influence malaria transmission. CONCLUSION: This study highlights farming activities as a risk factor for malaria infection in agro-communities. Integrated malaria control measures in agricultural communities should therefore include water and environmental management practices.

Alterations in histological, biochemical and hematological parameters in Plasmodium berghei NK-65 infected balb/c mice treated with Bridelia ferruginea stem bark extract.

BACKGROUND: Recent ethnomedicinal studies on Bridelia ferruginea Benth (family Phyllanthaceae) as an antiplasmodial remedy have established its potency as a strong prophylactic and chemosuppressive agent. Human consumption of medicinal herbs without adequate evaluation of its efficacy and safety can result in grave physiological and pathological consequences. Therefore, this study assessed the antiplasmodial bioactivity, biochemical, hematological, histopathological and toxicity profile of the ethanolic stem bark extract of B. ferruginea in mice. METHODS: Ethanolic stem bark extract of B. ferruginea (200, 400 and 800 mg/kg) were orally administered to Plasmodium berghei-infected mice in models and were subsequently observed for mortality, behavioral changes and signs of toxicity. Acute evaluation was experimented at 1,000 mg/kg for 28 days. Occult blood obtained from the euthanized mice were subjected to biochemical and hematological assays. A comprehensive assessment of the histology of the liver and kidney was also ascertained. The median lethal dose (LD50) was determined and extrapolated using the regression equation obtained from the plot of the probits of mortalities (y) and the log of doses (log10C). RESULTS: Different concentrations of the phytochemical secondary metabolites were revealed. Antiplasmodial bioactivity was established at the 200, 400 and 800 mg/kg of the herbal extract with a dearth in parasitemia at different days post-treatment. The 800 mg/kg group responded by exhibiting a dose-dependent decrease in parasitemia comparable with the chloroquine bi-phosphate group. Significant alterations in the histology of the liver and kidney of the 1,000 mg/kg group was documented. There was a reduction in the titers of LDH, ALT, AST, and urea in the treated group when compared with the control (p < 0.05). Antioxidant profiles were also highly significant with elevation in SOD, GPx, and CAT, but a reduction in MDA. LD50 was established at 424 mg/kg. CONCLUSION: B. ferruginea Benth (family Phyllanthaceae) is a potent antiplasmodial, antioxidant, regenerative and ameliorative herbal remedy if administered in controlled dosage.

Evaluation of cytogenotoxic potential of Morinda lucida leaf extract on Swiss albino male mice using two bioassays.

BACKGROUND: Utilization of Morinda lucida for the treatment of ailments such as malaria, diarrhea, infertility in women, and dysentery in many countries including Nigeria is on increase due to its efficiency, availability, and affordability. However, its cytogenotoxicity has not been elucidated. This study investigated the phytochemical constituents and possible genotoxic and cytotoxic effects of M. lucida leaf extract in Swiss albino male mice using bone marrow micronucleus and sperm morphology assays. METHODS: Plant materials was collected, thoroughly washed, and air-dried at room temperature prior to maceration. The extract was assessed for the presence of the phytochemical compounds. Swiss albino male mice (Mus musculus) (n=4) were treated with different concentrations of this extract (400 mg/kg, 800 mg/kg, and 1200 mg/kg) while distilled water was used as negative control. RESULTS: Phytochemical analysis revealed that the extract contains saponins, terpenoids, flavonoids, glycosides, and tannins. We observed micronucleated polychromatic erythrocytes (PCE) and normochromatic erythrocytes (NCE) of 3.20%, 1.10%, and 1.95% at different concentrations of 400 mg/kg, 800 mg/kg, and 1200 mg/kg respectively in the treated animals. The result showed no significant increase in the frequency of abnormalities (p < 0.05) when compared to the negative control; however, in separate analysis of mono-micronucleated PCE and mono-micronucleated NCE per group, a significant increase at 400 mg/kg and 1200 mg/kg concentrations was observed. The sperm anomalies decreased with increase in concentration. CONCLUSIONS: This study recommends 800 mg/kg concentration of the plant extract; however, it should be further and properly investigated as it contains some pharmaceutical components that can be used for pharmacological purposes.

Evaluation of the Clinical Proficiency of RDTs, Microscopy and Nested PCR in the Diagnosis of Symptomatic Malaria in Ilorin, North-Central, Nigeria.

BACKGROUND: Accurate laboratory diagnosis of suspected malaria is the hallmark to the control of the disease. AIM: The clinical proficiency of commercial Rapid Diagnostic test kits (RDTs) using nested PCR as quality control was evaluated among patients attending two public healthcare providing institutions in Ilorin, Kwara state, North-Central, Nigeria. METHOD: A cross-sectional evaluation of finger prick blood samples of volunteer patients were accessed for malaria parasites with pLDH, HRP2, Pf, Pf/PAN and nested PCR molecular assays. The data derived were analysed using standard formulae for diagnostic accuracy, and the obtained predictive values were subjected to a comparison with one-way analysis of variance (ANOVA). RESULT: Three hundred and sixty-eight (368) patients comprising 203 (55%) females and 165 (45%) males participated in this study. Routine microscopy revealed that 54 (32.7%) males and 80 (39.4%) was infected with Plasmodium falciparum. SD Bioline (pLDH) 47.4%; Carestart Malaria (HRP2) 49.8% recorded low sensitivities. Micropoint (pfPAN) 82.8% and Micropoint (Mal. Pf) 64.4% recorded a high sensitivity. SD Bioline (pLDH) 67.4%; Carestart Malaria (HRP2) 85.9%; Micropoint (PfPAN) 62.2% and Micropoint (Mal. Pf) 86.7% had high specificities. The positive predictive value (PPV) ranged from 67.7% to 85.94%, while the negative predictive values (NPV) of 64.4% for SD Bioline (pLDH); 86.7% for Carestart Malaria (HRP2); 89.3% for Micropoint (pfPAN) and 58.5% for Micropoint (Mal. Pf). Agarose gel analysis of P. falciparumssrRNA gene (206 bp) for 28 specimens containing 10% concordant and discordant samples showed that all 12 negative specimens for RDTs and routine microscopy were truly negative for nPCR. However, the remaining 16 specimens were positive for nPCR and showed discrepancies with routine microscopy and RDTs. Cohen's interrater diagnostic measure analysis revealed that the weighted kappa for the RDTs was moderate 0.417 (p=0.027), 95%CI (0.756, 0.078) and good for nPCR 0.720 (p < 0.001), 95%CI (0.963, 0.477). The area under the curve (AUC) specify that nPCR has been more effective than the RDTs (nPCRAUC = 0.875; p < 0.001 and RDTsAUC = 0.708; p = 0.063). CONCLUSION: A thorough large-scale quality control is advocated on all commercial RDTs being used in most sub-Saharan African countries. This is to avoid double jeopardy consequent upon misdiagnosis on unidentified positive cases serving as pool reservoir for the insect vector and cyclical infection and re-infection of the populace.