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Safety of natural products is a priority before they are acceptable for consumption. Alstonia boonei De Wild (Apocynaceae) stem-bark and Picralima nitida (Stapf) T. & H. Dur. (Apocynaceae) seed are combined into a powder dosage form for the treatment of malaria fever. This study evaluated the central nervous system effects and the toxicity of the remedy on acute and repeated doses with a view to providing information on its safety. The powder mixture (ratio 1:2) of A. boonei stem-bark and P. nitida seed was extracted with water by the decoction method, concentrated in vacuo and freeze-dried. The acute toxicity of the extractive was determined by Lorke's method. For the novelty-induced behaviour tests, 24 mice (18–22 g) of four groups (six mice per group) were orally given the aqueous solution of the extractive at 12.5, 25 and 50 mg/kg while the control group was given distilled water once daily for 30 days, after which the liver, kidney, brain, spleen and testes of each animal were humanely harvested for histopathological examination. At 25 mg/kg, a significant increase (P < 0.05) was observed in the grooming activity of the mice on acute and repeated doses. Histopathological analysis revealed that all the organs were essentially normal when compared with the control. The repeated oral administration of the extractive was relatively safe at each of the doses tested. [ABSTRACT FROM AUTHOR]

Background and Objective: MAMA decoction (MD) is an antimalarial product prepared from the leaves of Mangifera indica L. (Anacardiaceae), Alstonia boonei De Wild (Apocynaceae), Morinda lucida Benth (Rubiaceae) and Azadirachta indica A. Juss (Meliaceae). A previous report showed that MD enhanced the efficacy of amodiaquine (AQ) in malaria-infected mice, thus suggesting a herb–drug interaction. The present study hence evaluated the effect of MD on the disposition of AQ in mice with a view to investigating a possible pharmacokinetic interaction. Methods: In a 3-period study design, three groups of mice (n = 72) were administered oral doses of AQ (10 mg/kg/day) alone, concurrently with MD (120 mg/kg/day), and in the 3rd period, mice were given AQ after a 3-day pre-treatment with MD. Blood samples were collected between 0 and 96 h for quantification of AQ and its major metabolite, desethylamodiaquine, by a validated high-performance liquid chromatography method. Results: Maximum concentrations of AQ increased by 12% with the concurrent dosing of MD and by 85% in the group of mice pre-treated with MD. The exposure and half-life of desethylamodiaquine increased by approximately 11% and 21%, respectively, with concurrent administration. Corresponding increases of approximately 20% and 33% of desethylamodiaquine were also observed in mice pre-treated with MD. Conclusion: MD influenced the pharmacokinetics of AQ and desethylamodiaquine, its major metabolite. The increase in the half-life and systemic exposure of AQ following its co-administration with MD may provide a basis for the enhanced pharmacological effect of the combination in an earlier study in Plasmodium-infected mice. [ABSTRACT FROM AUTHOR]

Mangifera indica, Alstonia boonei, Morinda lucida and Azadirachta indica (MAMA) decoction, commonly prepared and used in Nigeria from 1:1:1:1 ratio of Mangifera indica L. (Anacardiaceae), Alstonia boonei De Wild (Apocynaceae), Morinda lucida Benth (Rubiaceae), and Azadirachta indica A. Juss (Meliaceae) leaves, plus four new variants of this combination were subjected to three in vivo antimalarial test models using chloroquine-sensitive Plasmodium berghei berghei to determine the most active under each of the test models. Using the original formulation, MAMA (1:1:1:1) which gave ED and ED of 101.54 ± 2.95 and 227.18 ± 2.95, respectively, as reference for comparison, MAMA-1 (1:2:2:2), with 79.58 ± 1.30 and 170.98 ± 1.30, gave significantly ( p < 0.05) higher survival at 85 and 340 mg/kg when 80 % of the mice survived for 15.6 and 17.8 days, respectively, while MAMA-2 (2:1:2:2), with 83.57 ± 1.93 and 164.23 ± 1.93, gave comparable survival except at 170 mg/kg with 60 % survivors for 12 days. MAMA-1 and MAMA-2 were the best curative formulations with MAMA-1 giving additional prophylactic activity. MAMA-3 (2:2:2:1) with 98.70 ± 0.91 and 220.17 ± 0.91, gave comparable ( p > 0.05) survival at 85 mg/kg with 60 % survival for 13.2 days and significantly higher survival at 42.5 mg/kg for 17 days with 40 % survival. Both MAMA and MAMA-3 were the best chemosuppressive formulations plus additional curative activities. MAMA-4 (1:1:2:2), the best prophylactic formulation with 94.87 ± 2.43 and 201.20 ± 2.43 gave significantly higher ( p < 0.05) survival at all doses except at 21.25 mg/kg which gave 60 % survival up to 10 days. Thus, the antimalarial therapy desired, following appropriate diagnosis, whether prophylactic, chemosuppressive or curative would determine which of the MAMA decoction formulations to be prescribed. This phenomenon of formulary optimization may also be applied to other pharmacological activities. [ABSTRACT FROM AUTHOR]

The use of decoctions of different plant materials is common practice in antimalarial ethnomedicine in Africa. Scientific evaluation of such herbal combinations to verify the claims is important. The study has evaluated the antimalarial efficacy of MAMA decoction (MD), a multicomponent herbal preparation and its individual plant components, namely leaves of Morinda lucida Benth [Rubiaceae] (ML), Azadirachta indica A. Juss [Meliaceae] (AI), Alstonia boonei De Wild [Apocynaceae] (AB) and Mangifera indica L [Anacardiaceae] (MI) in Plasmodium berghei-infected mice. Each decoction was prepared by boiling the powdered leaf in water, concentrated in vacuo and freeze-dried. The acute toxicity of MD (LD = 3.8 g/kg) was determined using Lorke's method. The antimalarial activities of MD and its plant components were evaluated by oral administration of the freeze-dried extracts (15-240 mg/kg) using the early malaria infection test model. The established malaria infection test was used to evaluate MD (60-240 mg/kg) while amodiaquine [10 mg/kg] (AQ) and distilled water were employed as the positive and negative controls, respectively. From the early malaria infection test, the effective doses at 50 % (ED) and 90 % (ED) for MD, AB, AI, ML, MI and AQ were 43, 79, 140, 134, 208 and 3.9 mg/kg and 202, 276, 291, 408, 480 and 9.2 mg/kg, respectively. For the established infection test, MD (240 mg/kg) and AQ gave parasite clearance of 55 and 95 % on day 5 of treatment. MD possesses antimalarial activity and is relatively safe. [ABSTRACT FROM AUTHOR]