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BackgroundMalaria is one of the leading causes of morbidity and/or mortality in tropical Africa. The spread and development of resistance to chemical antimalarial drugs and the relatively high cost of the latter are problems associated with malaria control and are reasons to promote the use of plants to meet healthcare needs to treat malaria. The aim of this study was to evaluate antiplasmodial activities of extracts of Erythrina sigmoidea (Mah quat), which is traditionally used for the treatment of malaria in the western region of Cameroon.Material and methodsThe ethanol extract of E. sigmoidea stem bark was obtained through the maceration process using 95% ethanol, while the aqueous extract was prepared by infusion. The in vitro antiplasmodial effect of extracts against P. falciparum chloroquine-sensitive (3D7) and chloroquine-resistant (Dd2) strains was determined using the Trager and Jensen method. On the other hand, the in vivo antimalarial activity of the extract was evaluated in mice infected with Plasmodium berghei strain NK65 using the Peters’ 4-day suppressive test and Ryley test (curative test). A total of 36 mice were used, subdivided into six groups of six mice each: one normal control, a negative control, a positive control, and three other groups for the tested product. Blood samples were collected on the 10th day of each test for hematological parameters.ResultsThe aqueous extract had an in vitro antiplasmodial activity against the chloroquine-sensitive strain with an IC50 of 29.51 ± 3.63 µg/mL and against the chloroquine-resistant strain with an IC50 of 35.23 ± 3.17 µg/mL. The highest in vitro antiplasmodial activity was observed with the ethanol extract against the chloroquine-sensitive strain with an IC50 of 6.44 ± 0.08 µg/mL and against the chloroquine-resistant strain with an IC50 of 7.53 ± 0.22 µg/mL. The ethanol extract demonstrated suppressive activity in vivo with reduction rates of 87.69%, 86.79%, and 81.08% at doses of 500 mg/kg, 250 mg/kg, and 125 mg/kg, respectively; and curative activity in vivo with reduction rates of 80%, 78.5%, and 77.5% at doses of 500 mg/kg, 250 mg/kg, and 125 mg/kg, respectively. The number of white blood cells in the negative control (44.55 ± 5.02 103/µL) was higher compared to the other groups. As for the red blood cells, we observed a massive destruction of the latter in the infected and untreated group (5.82 ± 1.50 106/µL) compared to the infected and ethanol extract-treated groups (8.74 ± 1.57 106/µL for 500 mg/kg, 7.54 ± 1.77 106/µL for 250 mg/kg, and 8.9 ± 1.50 106/µL for 125 mg/kg).ConclusionThis study provides scientific data on the use of E. sigmoidea by the local population for the treatment of malaria. It shows that E. sigmoidea has antiplasmodial activity, and we also see that there are differences between the parameters that we have in the treated groups and those of the untreated group. However, toxicity tests are necessary to assess its safety.

Background. Parasitic infection remains a serious health trade for humans and livestock. The purpose of this study was to present scientific proof of the anthelmintic properties of Khaya grandifoliola, which the native population uses to cure helminthiasis. Method. Fresh Heligmosomoides polygyrus eggs were isolated from faecal samples of experimentally infected mice. The faecal material was cultured, and L1 and L2 larval stages were recovered after 48 and 120 hours, respectively. Using the worm microtracker, the anthelminthic efficacy of the extracts against H. polygyrus was assessed. Two different extracts (aqueous and ethanol extracts) were prepared. For the ovicidal and larvicidal activities, 100 µL of various concentrations of plant extracts, levamisole and 1.5% dimethyl sulfoxide (DMSO), were introduced into a 96-well microplate titer followed by the addition of 100 µL of embryonated eggs (60 eggs) for the ovicidal activity and 100 µL of L1 or L2 larvae (50 larvae) for the larvicidal activity. The movement of the worm was monitored for 24 hours in the worm microtracker at 27°C. The Glide module of the Schrodinger Maestro software was used to perform docking studies. Results. For the aqueous extracts, the highest percentage of inhibition of hatching was 42.77 ± 12% at 7.5 mg/mL. The IC50 values for the ethanol (0.36 mg/mL) extract showed that the ethanol extract had a good inhibitory effect on the ability of parasites to hatch from eggs. The inhibition percentage of L1 larvae motility at 7.5 mg/mL was 98.0 ± 1.66% and 83.33 ± 1.66% for ethanol and aqueous extracts, respectively. The negative controls, distilled water and 1.5% DMSO, had no inhibitory impact on larvae. On L1-larvae, the drug of choice levamisole (positive control) had the highest percentage effect (100.0%). Six compounds had the highest docking score and their interactions with the receptor as well. Grandiamide A interacts most with tyrosine, glycine, phenylalanine, asparagine, and serine, and its benzene ring and oxygens inhibit these receptors. Carbonyl and hydroxyl (OH) groups connect grandiamide D to asparagine, isoleucine, and phenylalanine, respectively. By donating hydrogen to the receptor through OH groups, D-glucopyranose-6-phosphate also forms relatively strong hydrogen bonds with its oxygen-bound phosphorus and the receptor. 1-O-deacetylkhayanolide E interacts most with serine and glutamic acid. The carbamic acid benzyl ester of carbamic acid [(1S)-1-phenyl-2-[(4-methylphenyl) sulfinyl] ethyl] interacts most with the receptor with carbonyl groups and with asparagine and serine. With its abundant hydroxide, D-mannitol acts as a hydrogen donor and acceptor and interacts most strongly with amino acids such as glycine, asparagine, aspartic acid, alanine, and glutamic acid. Conclusions. K. grandifoliola extracts possess anthelminthic properties. However, in vivo studies are still necessary to demonstrate the effectiveness of this plant for the treatment of helminthiasis.

Background. Helminthiasis is endemic in Chad and constitutes a public health problem, particularly among school-age children. The aim of this study was to evaluate the anthelmintic activity of extracts of Khaya anthotheca and Faidherbia albida used in Chad by traditional healers for the treatment of helminthiasis. Methods. The anthelmintic activity was assessed against Heligmosomoides polygyrus and Caenorhabditis elegans larvae using the Worm Microtracker. Embryonated eggs, L1, L2, and L3 larvae of H. polygyrus were obtained after 24 h, 48 h, and 7 days of coproculture and L4 larvae of C. elegans culture using standard procedures. One hundred microliters of extracts at various concentrations, with albendazole and distilled water were, put in contact with 100 µL of H. polygyrus suspension (containing 50 parasites at various developmental stages) in a microplate and incubated for 20 h at 25°C in the Worm Microtracker. The same procedure was adopted for C. elegans, but with 180 µL of OP50. 19 µL of C. elegans suspension (containing 50 larvae) was put in contact with 1 µL of extract at various concentrations and incubated in the Worm Microtracker. Docking studies were carried out using the Schrodinger Maestro software’s Glide module. The score function in the software was used to rank and group distinct possible adduct structures generated by molecular docking. Results. The aqueous and ethanolic extracts of F. albida at a concentration of 2.5 mg/mL showed the same activity as albendazole (100 ± 0.00) on hatching. The IC50s of the aqueous extracts of the two plants (IC50: 0.6212 mg/mL and 0.71 mg/mL, respectively) were comparable on egg hatching of H. polygyrus with no significant difference (p≥0.05) with respect to the ethanol extracts (IC50: 0.70 mg/mL and 0.81 mg/mL, respectively). There was no significant difference between the percentage inhibition of extracts and albendazole on the L1 larvae of H. polygyrus (p≥0.05). The aqueous extracts acted more effectively than the ethanol extracts on the L1 larvae of H. polygyrus with an IC50 of 0.5588 and ∼9.858e − 005 mg/ml, respectively, for K. anthotheca and F. albida. The aqueous extracts of K. anthotheca and F. albida on L3 larvae of H. polygyrus had inhibitory percentages of 92.6 ± 0.62 and 91.37 ± 0.8 at 2.5 mg/mL which were lower than albendazole (100 ± 0.00). The aqueous extracts of K. anthotheca and F. albida on C. elegance showed IC50 of 0.2775 µg/mL and 0.5115 µg/mL, respectively, and were more effective than the ethanol extracts. Examining K. anthotheca and F. albida through the interaction with the protein receptor and its results also confirmed our assumption that the compound used has hydroxyl and carbonyl groups as well as aromatic rings and is exposed to phenolic and flavonoid groups in a more specific way, and it shows a better inhibitory effect. Conclusions. This study scientifically validates the use of extracts of the two plants in the traditional treatment of helminthiasis. However, it will be necessary to evaluate the in vivo anthelmintic activity and toxicity. Examining the ADME properties of these compounds also supports the potential of these ligands to be transformed into pharmaceutical forms.

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.

Background. Cerebral malaria is one of the most severe and dangerous forms of malaria and is potentially fatal. This study was aimed at evaluating the anticerebral malaria efficacy of Khaya grandifoliola used by traditional healers. Method. Fifty grams of Khaya grandifoliola stem bark was macerated in 1 L ethanol (95%) for 72 h. The filtrate was dried at 40°C until the obtention of a dry extract. The antimalarial test was evaluated using the Peter 4-day suppressive test and the Rane curative test. Mice were group into 6 groups of 6 mice each. For the antioxidant test, parameters such as malondialdehyde (MDA), superoxide dismutase (SOD), glutathione (GSH), catalase (CAT), and nitric oxide (NO) were assessed. The livers of mice were crushed and centrifuged in order to be measured. Aspartate aminotransferase (ASAT) and alanine aminotransferase (ALAT) using the Dutch Diagnostics Kit and blood were collected for haematological parameters. Results. The ethanol extract showed a suppressive activity of 78.12%, 75.30%, and 68.69% at 500 mg/kg, 250 mg/kg, and 125 mg/kg, respectively. Similarly, the curative activity showed a statistically significant reduction in parasitemia (p

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.

Background. Malaria remains a major public health problem in the tropical and subtropical regions. This study aimed of investigating the antimalarial and antioxidant activities of ethanol extract of Lophira lanceolata stem bark. Methodology. The antimalarial activity was determined using the Peter 4-days’ suppressive and Rane’s curative tests on Swiss albino: these mice were infected with 1×107 parasitized red blood cells. The percentage reduction of parasitemia was related to each test, and the liver homogenate was used to assay malondialdehyde, superoxide dismutase, nitrogen monoxide, catalase, and glutathione for the evaluation of oxidative stress. During the curative test, blood was collected for hematological parameters, alanine aminotransferase and aspartate aminotransferase to evaluate liver function. Result. The ethanol extract of L. lanceolata showed a dose-dependent suppressive activity with the highest suppression of 88.22% at 500 mg/kg. Suppression produced by the extract was not significantly higher than that of the reference drug with 96.1%. Similarly, the extract at doses 125, 250, and 500 mg/kg showed significant decreases (P

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

Background. Malaria is a serious public health problem, especially in sub-Saharan Africa. The aim of this study was to scientifically provide baseline information on the use of Khaya grandifoliola stem bark as an antimalaria drug by traditional healers. Method. The stem barks of K.grandifoliola were harvested and dried to obtain powder, and fifty grams of the powder were soaked in ethanol and hot distilled water respectively, for the preparation of ethanol and aqueous extracts, then dried in an oven at 40°C for the ethanol extract and 50°C for the aqueous extract. Plasmodium falciparum strains 3D7 sensitive and Dd2 resistant to chloroquine, were used to evaluate in vitro antiplasmodial activity using SYBR Green. The ability of the extracts to prevent oxidative stress was assessed by trapping 2, 2′-diphenyl-1-picrylhydrazyl (DPPH); nitric oxide, hydrogen peroxide and ferric reducing power. The cytotoxicity test of the extracts was carried out on RAW 264.7 cell lines and on erythrocytes. The data obtained were entered in the Excel software, then in Graph pad where the IC50 was calculated and the curves plotted. Results. The fifty percent inhibition (IC50) of the antiplasmodial activity of the chloroquine-resistant strain PfDd2 were 54.27 ± 2.41 μg/mL and 31.19 ± 4.06 μg/mL respectively, for the aqueous and ethanol extracts. As for the Chloroquino-sensitive Pf3D7, IC50 of 53.06 μg/mL was obtained for the aqueous extract and 28.03 ± 1.90 μg/mL for ethanol. The DPPH radical scavenging activity presented IC50 of 104 μg/mL for the aqueous and 2.617 μg/mL for the ethanol extract; for the Nitric oxide (NO) presented an IC50 of 301 ± 21 μg/mL for the aqueous extract 140.7 ± 21 μg/mL for the ethanol; for hydrogen peroxide the ethanol and aqueous presented IC50 of 845.1 ± 21 μg/mL and 509.4 ± 21 μg/mL respectively. The cytotoxicity on RAW 264.7 cells presented High CC50 in particular >1000 μg/mL and 467.4 μg/mL respectively for the aqueous and ethanol extract. Conclusion. Extracts of Khaya grandifoliola exhibited antiplasmodial activity. The ability to inhibit oxidative stress as well as lower cell toxicity on RAW 264.7 and erythrocytes, is a good indicator. However, in vivo tests remain important in order to confirm the use of this plant for the treatment of malaria.

Background. Malaria is the leading cause of morbidity and mortality in African countries. We aimed this study at evaluating the in vitro antiplasmodial, antioxidant, and cytotoxicity activity of Lophira lanceolata extracts. Method. The aqueous and ethanol extracts were obtained by maceration. It tested in vitro the extracts against Plasmodium falciparum 3D7 and multiresistance Dd2. Macrophage cell lines (RAW 264.7 cells) and red blood cells were used for cytotoxicity tests. The antioxidant activity was assessed by 1,1-diphenyl-2-picrylhydrazine (DPPH), hydrogen peroxide (H2O2), nitric oxide (NO) reduction, and ferric reducing antioxidant power (FRAP) scavenging. Results. The in vitro antiplasmodial results showed that the ethanol extract was the most active, with IC50 of 24.51 ± 4.77 µg/mL and 31.86 ± 3.10 µg/mL, respectively, on the resistant Dd2 and sensitive 3D7 strains unlike the aqueous which indicated moderate activity with an IC50 of 51.36 ± 4.86 μg/mL and 56.36 ± 4.27 μg/mL, respectively, on the resistant Dd2 and sensitive (3D7) strains. However, the ethanol extract had the highest activity, with an IC50 of 8.153 g/mL, 1915 g/mL, 30.81 g/mL, and 54.66 g/mL, respectively, for DPPH, H2O2, NO, and FRAP, while the aqueous extract had an IC50 of 6.724, 2387681, 185.7, and 152.0 g/mL, respectively, for DPPH, H2O2, NO, and FRAP. The cytotoxicity test reveals that both extracts do not promote red blood cell haemolysis. They presented weak activity against RAW 264.7 cells and red blood cells. Conclusion. According to these findings, the aqueous and ethanol extracts have antiplasmodial and antioxidant activity but with no cytotoxic effects on red blood cells or RAW cells. However, it will be important to investigate the in vivo antiplasmodial and antioxidant activity of these extracts.

Background. There are about 13 parasitic infections that are responsible for significant morbidity and mortality but have not received the attention they deserve; thus, they are now known as “neglected tropical diseases” (NTDs). This study was aimed at evaluating the antihelminthic activities of Lophira lanceolata using an automated high-throughput method. Methods. The antihelminthic activity effect of the extracts against H. polygyrus was determined using an automated high-throughput method. For the egg-hatching test, 100 μL of embryonated egg suspension (60 eggs) was added to 100 μL of various concentrations of extracts, levamisole, and 1.5% DMSO in a 96-well round-bottom microtitre plate. After mixing, the 96-well microplate was placed in WMicroTracker and incubated for 24 h at 25°C; the movements were recorded every 30 minutes. The same procedure was used for the larval motility assays, where 100 μL of L1 or L2 larvae (50 larvae) were put in contact with 100 μL of various concentrations of extracts. Results. The ovicidal activity (hatching) had an IC50 of 1.4 mg/mL for the ethanol extract. The aqueous and ethanol extracts of L. lanceolata showed larvicidal activity on the L1 larvae with IC50 of 1.85 mg/mL and 2.4 mg/mL, respectively, as well as on the L2 larvae with IC50 values of 1.08 mg/mL and 1.02 mg/mL for the aqueous and ethanol extracts, respectively. These results showed that the aqueous extract exhibited a stronger inhibitory power on the hatching rate of parasites than ethanol extracts, while the contrary effect was observed for the larval motility assays. Conclusion. This study provides scientific data on the use of L. lanceolata by the local population for the treatment of helminthiases. However, in vivo and toxicity tests are necessary to assess its activity and safety.

Background. Malaria is one of the most critical diseases causing about 219 million cases worldwide in developing countries. The spread and development of resistance against chemical antimalarial drugs is one of the major problems associated with malaria control. The present study was to investigate the antimalarial efficacy of ethyl acetate extract and one fraction of Bidens pilosa in vivo in order to support the usage of this plant by traditional healers to treat malaria. Methods. The extracts were prepared by maceration of B. pilosa leaf powder in ethyl acetate. The liquid filtrate of the extract and the best in vitro antiplasmodial fraction using HPLC were concentrated and evaporated using a rotavapor under vacuum to dryness. The antimalarial activity of B. pilosa plant products were evaluated in vivo against Plasmodium berghei infected mice according to the Peter and Rane test. The antimalarial efficacy of the a selected crude extract (ethyl acetate extract) was evaluated at 125, 250, and 500 mg/kg, while a selected fraction from ethyl acetate extract (fraction 12) was evaluated at 62.5 and 125 mg/kg. Blood from experimental animals was collected to assess hematological parameters. Results. The crude extract of ethyl acetate and fraction 12 demonstrated 100% in vivo parasite suppressive activity at doses of 500 mg/kg and 125 mg/kg, respectively, for the crude extract and fraction 12. The mice treated with 250 and 500 mg/kg had their parasitemia (intraerythrocytic phase of P. Berghei) drop considerably, disappearing by the 8th day in mice receiving 500 mg/kg. The ethyl acetate extract of B. pilosa, fraction 12 showed an even higher antiplasmodial activity. By the 5th day of the experiment, the treatment led to a modification of hematological parameters in mice. The chloroquine (5 mg/kg), fraction 12 (125 mg/kg), and the crude extract (500 mg/kg) groups all survived the 30 days of the experiment, while the negative control group registered 100% of the deaths. Conclusion. This study scientifically supports the use of Bidens pilosa leaves in the traditional treatment of malaria. However, the mode of action and in vivo toxicity of the plant still need to be assessed.

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.