RESUMO
Background: The spread of drug resistance is a significant issue, particularly in endemic countries with limited resources. The aim of this study was to evaluate antimalarial and antioxidant activity of B. micrantha in order to justify its use in traditional medicine. Methods: Evaluation of the in vivo antimalarial activity of B. micrantha was carried out according to the model of the suppressive and curative test of Peters' over 4 days in infected Swiss albino mice. Antioxidant parameters and stress were measured after intraperitoneal administration of 1 × 107 infected red blood cells. Results: At doses of 150 mg/kg, 300 mg/kg, and 600 mg/kg, administration of B. micrantha substantially produced suppression of P. berghei infection by 67.75%, 73.46%, and 78.99%, respectively, while 84.64% of the untreated group (1% DMSO) had suppression from chloroquine. The curative test significantly decreased the levels of parasitaemia and death in the treated groups. Furthermore, after B. micrantha extract was given to infected mice, a noteworthy increase in total protein, aspartate aminotransferase (AST), and alanine aminotransferase (ALT) was observed. On the other hand, hepatic catalase (CAT) and superoxide dismutase (SOD) productions were considerably greater than that of the healthy control. Mice had considerably lower levels of nonenzymatic antioxidant markers such as glutathione, NO, and MDA showing that the liver was protected. Conclusion: The infected groups responded favorably to the ethanol extract of B. micrantha. This result justifies investigation for its use in Cameroon.
RESUMO
Introduction: Resistance to common antimalarial drugs and persistence of the endemicity of malaria constitute a major public health problem in Cameroon. The aim of this study was to evaluate the in vitro antiplasmodial, antioxidant, and cytotoxic activities of aqueous and ethanol extracts of Bridelia micrantha used by Cameroonian traditional healers for the treatment of malaria. Methods: Aqueous and ethanolic stem bark extracts were prepared according to standard procedures. The SYBR Green method was used for antiplasmodial activity on strains of Plasmodium falciparum sensitive to chloroquine (3D7) and resistant (Dd2). In vitro antioxidant activities of B. micrantha were determined using the scavenging activity of 2,2'-diphenyl-1-picrylhydrazyl, nitric oxide, ferric reducing power, and hydrogen peroxide as well as their cytotoxicity on RAW 264.7 macrophage cells and red blood cells (RBC). Results: The aqueous and ethanol extracts of Bridelia micrantha showed antiplasmodial activity on the 3D7 strain with IC50 of 31.65 ± 0.79 µg/ml and 19.41 ± 2.93 µg/ml, respectively, as well as 37.64 ± 0.77 µg/ml and 36.22 ± 1.04 µg/ml for the Dd2 strain, respectively. The aqueous and ethanol extracts showed free radical scavenging properties. The IC50 aqueous and ethanol extract was approximately 0.0001737 µg/ml, 42.92 µg/ml, 1197 µg/ml, 63.78 µg/ml and 4.617 µg/ml, 429.9 µg/ml, 511 µg/ml, and 69.32 µg/ml for DPPH, NO, H2O2, and FRAP, respectively, which were compared to ascorbic acid (8.610e - 005 µg/ml, 2901 µg/ml, 3237 µg/ml, and 18.57 µg/ml). The aqueous and ethanol extracts of B. micrantha were found to be nontoxic with CC50 values of 950 ± 6.6 µg/ml and 308.3 ± 45.4 µg/ml, respectively. Haemolysis test showed that the two extracts were not toxic. Conclusion: These results suggest that B. micrantha can serve as an antimalarial agent. However, further studies are needed to validate the use of B. micrantha as an antimalarial.
