Antimalarial Efficacy of Ethanol Extract of Bridelia micrantha Stem Bark against Plasmodium berghei-Infected Mice.

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.

Nematocidal Activity of Ethanol and Aqueous Extracts of Persea americana Seeds against Heligmosomoides polygyrus using the Worm Microtracker Method.

Background: Infections with gastrointestinal helminths constitute a serious obstacle to the good health of the local population in most African Countries. The aim of this study was to evaluate the anthelminthic activity of Persea americana ethanol and aqueous extracts against Heligmosomoides polygyrus using the worm microtracker. Method: Aqueous and ethanolic extracts of P. americana were prepared. Different concentrations of the extracts were tested against the egg and larvae stages of H. polygyrus using an automated high-throughput method. Briefly, embryonated eggs and larvae of this parasite were obtained after the incubation of fresh eggs at 25°C for 24, 48, and 96 hours for embryonated eggs, L1 and L2 larvae, respectively. One hundred microliters of the plant extracts at various concentrations were put in contact in a 96-well microplate with a suspension of 100 embryonated eggs in a total volume of 200 µL and incubated in a worm microtracker where the motility of the worms was recorded every 30 minutes for the ovicidal activity. The final tested extract concentration was 5, 2.5, 1.25, 0.625, and 0.3125 mg/mL, whereas ringer solution (0.95%) and 1.5% Dimethyl sulfoxide (DMSO) were used as negative controls and levamisole as positive control. The same method was used for larvicidal activities. The anthelmintic activity was determined using the average movement of the worms in the tested product compared with the negative control (1.5% DMSO and ringer solution). Results: The egg hatching rates of H. polygyrus had IC50 of 0.49 mg/mL (95% confidence interval: 71.70-92.03) and 0.22 mg/mL (95% confidence interval: 74.28-86.18) for the ethanol and aqueous extract, respectively. These IC50 indicate that the aqueous extract is more active for the inhibition of hatching at a 95% confidence interval. The aqueous and ethanol extracts presented mean inhibitory hatching rates of 78.33 ± 1.67% and 75.67 ± 1.15% at 5 mg/mL, respectively, with no significant differences. The highest percentage of inhibition of L1 larva was observed at 5 mg/mL with 89 ± 2.3%and 85 ± 2.7% for the ethanol and aqueous extracts, respectively. The lowest percentage of inhibition was observed at 0.3125 mg/mL, with 54.67 ± 3.38% and 49 ± 2.64% for the ethanol and aqueous extract, respectively. No significant differences were observed between the two extracts at 5 mg/mL with an inhibitory percentage of 90.67 ± 3.05% (ethanol) and 89.33 ± 2.08% (aqueous). Conclusion: Extracts of P. americana seeds possess nematocidal activity, however, further in silico and in vivo investigations are necessary to confirm their anthelminthic activity.

Antimalarial and Antioxidant Activities of Ethanolic Stem Bark Extract of Terminalia macroptera in Swiss Albino Mice Infected with Plasmodium berghei.

Background: Reduction of oxidative stress during malaria infection is considered as being of great benefit so long as treatment and drug development approaches are concerned. This study had the aim of evaluating the antimalarial and antioxidant activities of the ethanolic extract of Terminalia macroptera in Swiss albino mice infected with the Plasmodium berghei NK65 strain. Methods: In vivo, the antiplasmodial activity of the plant ethanolic extract was tested in a four-day suppressive and curative assay using P. berghei in Swiss albino mice. The extract was administered to the mice at doses of 125, 250, and 500 mg/kg per day. Then, parameters, such as parasite suppression and survival time of the mice, were evaluated. Furthermore, the effect of plant extract on liver damage, oxidative stress indicators, and lipid profile changes in P. berghei-infected mice were studied. Results: Administration of T. macroptera significantly suppressed P. berghei infection by 55.17%, 70.69%, and 71.10% at doses of 125, 250, and 500 mg/kg, respectively, whereas chloroquine had 84.64% suppression relative to the untreated group 1% Dimethyl sulfoxide (1% DMSO) at day 4 (post-infection) in the four-day suppressive test. This suppression activity rate was dose-dependent. The curative test also presented a significant reduction in parasitemia and an extension of the survival time of the treated groups. Treatment of infected parasitized mice with the extract of T. macroptera had a significant (p < 0.05) reduction in parameters, such as total protein, aspartate aminotransferase, and alanine aminotransferase. Infection may also lead to a significant increase in the enzymatic activity of liver catalase and superoxide dismutase compared with the normal control group. The non-enzymatic antioxidant activity in parasitized mice was significantly reduced in malondialdehyde and increased in glutathione and nitric oxide when compared with the normal control group. Conclusions: These findings support the ethnobotanical use of T. macroptera stem bark as an antimalarial remedy coupled with antioxidant activity. However, further in vivo toxicity tests are required to ascertain its safety.

Antiplasmodial, Antioxidant, and Cytotoxic Activity of Bridelia micrantha a Cameroonian Medicinal Plant Used for the Treatment of Malaria.

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.

Intestinal Helminth Infections and Associated Risk Factors among School-Aged Children of Bamendjou Community, West Region of Cameroon.

BACKGROUND: Infection with intestinal nematodes is of major public health concern worldwide, and school-age children and pregnant women are the principal victims. The present study was undertaken to provide baseline information on the status of gastrointestinal nematodes among school-age children in Bamendjou. Material and Methods. Four hundred and ninety-three (493) stool samples were collected from school children in six (6) different schools (two nursery, two primary, and two secondary schools). Qualitative and quantitative analyses of stool samples were done using the simple flotation and McMaster count techniques, respectively. RESULTS: Among the 493 participants, 57 (11.6%) stool samples were positive for at least one nematode species. Four nematodes are as follows: Ascaris sp., Trichuris sp., hookworms, and Strongyloides sp. with respective prevalence and intensities of infection of 6.1% and 2260 ± 6377.98, 3.4% and 223.53 ± 264.054, 3.0% and 416.67 ± 427.061, and 0.2% and 200 ± 00, respectively. The data on the prevalence of nematodes with respect to sex showed that females (13.1%) were more infected than males (12.2%) (P > 0.05). Furthermore, with respect to age, older children were more infected than younger ones. Cases of double parasitism were encountered with a prevalence of 1.2%. According to the fecal concentration of eggs, 61.90% of the infections were light. Risk factors such as drinking water from streams and not wearing shoes all the time were significant with infections. CONCLUSION: The relatively low overall prevalence (11.6%) obtained in this study shows that the national deworming campaign is proving effective, though a more holistic approach is required to prevent infections from bouncing back after such campaigns.

In Vivo Antiplasmodial Activity of Entandrophragma cylindricum (Sprague) Sprague Ethyl Acetate Extract in Plasmodium berghei-Infected Mice.

BACKGROUND: One of the most dangerous Plasmodium species is Plasmodium falciparum. Hence, it causes a higher rate of mortality. The resistance of Plasmodium falciparum to the ACT (Artemisinin-based Combination Therapies) has led to the search for new antimalarial drugs. The purpose of this research was to assess the in vivo antiplasmodial activity of Entandrophragma cylindricum ethyl acetate extract to provide a scientific basis for the use of this medicinal plant to treat malaria. METHODS: Entandrophragma cylindricum stem bark powder was macerated in ethyl acetate to obtain the extract. The extract liquid filtrate was concentrated, evaporated and dry using a Rotavapor. The Peter and Rane test were used for the suppressive and curative antiplasmodial activities at different doses (125, 250 and 500 mg/kg). A positive and negative control groups were administered chloroquine (5 mg/kg) and 10% hypromelose, respectively. To assess the parasitemia of the mice a thin blood smear was made. RESULTS: The ethyl acetate extract completely (100%) inhibited the development of P. berghei in the suppressive test at the dose of 500 mg/kg while that of the curative test was inhibited at 95%. The extract-treated group (500 mg/kg) and (Chloroquine (5 mg/kg) group all survived. The negative control group recorded a 100% mortality rate. CONCLUSION: The present study provides scientific confirmation on the use of E. cylindricum stem bark as an antiplasmodial remedy. However, the identification of the mode of action and the purification of the active compounds are necessary for further studies.