West African Traditional Medicine Research Articles

In Silico Screening of Phytocompounds from West African Traditional Medicine and Molecular Docking Targeting Dengue Virus Protein NS2B/NS3.

Traditional medicine offers a wide range of application for in silico study techniques. This drug research and development strategy is embryonic in the West African context, particularly in Burkina Faso, which is increasingly faced with emerging diseases such as dengue fever. Circulation of the 4 serotypes of this virus has been documented in the country. This study aims to evaluate the therapeutic potential of phytocompounds contained in the West African pharmacopoeia against dengue virus NS2B/NS3 protein, using computational methods integrating several software packages and databases. Based on a literature review, we identified 191 molecules from 30 plants known for their antiviral effects. Five met the inclusion criteria for molecular docking: patulin from calotropis procera, resiniferonol from Euphorbia poissonii, Securinol A from Flueggea virosa, Shikimic acid and Methyl gallate from Terminalia macroptera. The best binding scores were observed between resiniferonol and the serotypes 1, 2 and 4 NS2B/NS3 protease, with binding energies of -7.4 Kcal/mol, -6.8 Kcal/mol and -7.3 Kcal/mol respectively; while the NS2B/NS3 protease of serotype 3 had the best affinity for securinol A (-7 Kcal/mol). This study points the way to further research in computer aided drug design field and calls for multidisciplinary collaboration to promote West African medicinal plants against health challenges.

Cucurbitaceae species used as traditional medicine in West Africa

Background: The use of some Cucurbitaceae species for the treatment of diseases is an ancient practice in traditional medicine systems in Africa and the cucurbitacins among others have been reported to be responsible for most of these healing activities.Aim: This review discusses the relevance of Cucurbitaceae species in traditional medicine in some west African countries.Methods: A literature search was conducted on electronic databases such as Google Books, Google Scholar, Scopus and Web of Science. The search involved the use of several terms and free text words which include ‘Cucurbitaceae species in West Africa traditional medicine’; ‘medicinal plants of the Cucurbitaceae family used to treat diseases in west African communities’.Results: Several Cucurbitaceae species are used in the region either in similar ways or different ways for the treatment of different diseases. The leaves are the most utilised plant parts and decoctions are the most common method of preparation. From this study, 18 species of Cucurbitaceae used for medicinal purposes were reviewed from Nigeria; 4 from Benin, Ghana, Côte d’Ivoire and Mali, respectively; 1 from Togo; 5 from Senegal; 9 from Cameroon and 3 from Gabon and Burkina Faso, respectively. Momordica charantia and Momordica balsamina are often utilised for abortion in some west African countries. Momordica species and Lagenaria breviflora are utilised to treat diabetes, cough related to respiratory infections and viral infections such as measles and chickenpoxConclusions: In-depth research into these plants could help to develop a natural, novel cure for diabetes and coronavirus (COVID-19) and effective, cheap contraceptive.Contribution: This review highlights the significant role of Cucurbitaceae species in the treatment of a wide range of diseases and health issues in the WestAfrican traditional medicine system. The information provided could be used as a guide by research scientists for the formulation of natural products to cure a variety of diseases.

Strategy for the quality control of herbal preparations made of Sarcocephalus latifolius: Development and validation of a UHPLC-PDA method for quantification of angustoline and strictosamide and chemical profiling using LC-QToF.

Sarcocephalus latifolius is one of the most used plants in West African traditional medicine to treat malaria. The aim is to establish a strategy to control the quality of herbal preparations made from S. latifolius. A UHPLC-PDA method was developed for the determination and quantification of the two main bioactive compounds (angustoline and strictosamide) in various parts of the plant. Additionally, an LC-QToF with electrospray ionization method is described for the identification and confirmation of compounds in samples of different parts of the plant. With the UHPLC-PDA method, separation was achieved within 5min using a C18 column stationary phase at a temperature of 45°C and a gradient system with a mobile phase of water and acetonitrile, both containing 0.1% formic acid. The method was validated for linearity, accuracy, precision (repeatability and intermediate precision), limit of detection (LOD), and limit of quantification (LOQ). The LOD and LOQ of angustoline were found to be 0.3 and 0.8μg/ml, respectively, and those of strictosamide were found to be 0.1 and 0.3μg/ml, respectively. Using the LC-QToF method, 90 secondary metabolites, including four isolated compounds from the plant's roots, were identified from leaf, bark, and root samples of S. latifolius. This work is the first to propose a strategy to control the quality of herbal preparations made from S. latifolius. The developed method allows the quantification of the main bioactive compounds and the established chemical profile allows to distinguish the plant from any other species.

Garcinia kola treatment exhibits immunomodulatory properties while not affecting type 1 diabetes development in an experimental mouse model

ObjectiveT cells orchestrate an inflammatory response that destroys pancreatic insulin-producing β cells during the development of autoimmune type 1 diabetes (T1D). Garcinia kola Heckel (GK) is a plant widely exploited in West African traditional medicine. Some of the therapeutic effects of GK nut’s extract (GKE) have been suggested to be due to its anti-inflammatory potential. Since GKE has never been investigated in a T1D experimental model, nor in the T cells’ context, we aimed to determine whether GKE exhibits antidiabetic properties and affects T cells by its anticipated anti-inflammatory action.MethodsThe effect of aqueous GKE (aGKE) ingestion, 100 mg/kg daily by drinking water over the period of 6 weeks, has been tested in a low-dose streptozotocin-induced (LDSTZ) mouse model of autoimmune T1D. T cells were studied in vitro and in vivo in mice treated by aGKE.ResultsThe results showed that aGKE treatment, which started a week before induction of disease, neither delayed the development of T1D, nor reduced glycemia severity. Interestingly, aGKE treatment did affect T cells and their function, significantly decreasing the frequency of helper (TH) and cytotoxic (TC) T cells, while elevating the levels of pro-inflammatory cytokines, TNF-α, IL-6, and IFN-γ, and suppressing IL-2.ConclusionIn conclusion, our results did not confirm the antidiabetic property of GKE, while suggesting its therapeutic exploration in TH2-dependent pathologies that benefit from an aggravated TH1 response, such as allergies.

Essential Oil Compositions, Antibacterial and Antifungal Activities of Nigerian Members of the Burseraceae: Boswellia dalzielii and Canarium schweinfurthii

The Burseraceae is an important family of resin-producing trees and shrubs, which have yielded biologically active essential oils. Boswellia dalzielii and Canarium schweinfurthii are members of the family that are used in West African traditional medicine for a variety of ailments. The leaf essential oils of B. dalzielii have been obtained from 2 different locations in north-central Nigeria, while the leaf and stem bark essential oils of C. schweinfurthii have been obtained from 3 locations. The chemical compositions of the essential oils have been determined by gas chromatography-mass spectrometry and show wide variation, especially for the leaf essential oils. The leaf essential oils of B. dalzielii and C. schweinfurthii have been screened for antibacterial and antifungal activity; C. schweinfurthii leaf essential oil showed remarkable activity against Aspergillus niger with a minimum inhibitory concentration of 78.1 μg/mL.

Enabling West African Herbal-Based Traditional Medicine Digitizing: The WATRIMed Knowledge Graph.

The purpose of this study is to describe the design and development of the first release of the West African Herbal based Traditional Medicine Knowledge Graph (WATRIMed). It is a resource containing Traditional Medicine (TM) related entities and linked with publicly available knowledge bases in order to facilitate bringing West African TM into the digital world. The core model comprises currently 556 concepts including 143 identified West African medicinal plants and 108 recipes used by tradi-practitioners to treat 110 diseases and symptoms which are commonly encountered in this part of the world.

Antioxidant Capacity and Behavioral Relevance of a Polyphenolic Extract of Chrysanthellum americanum in a Rat Model of Irritable Bowel Syndrome.

Chrysanthellum americanum L. (Vatke) is a medicinal plant from the Compositae family used in west-African traditional medicine, known for its flavonoid and saponin richness and for its strong antioxidant potential. In the present study, we assessed the effects of Chrysanthellum americanum polyphenolic extract in the psychological stress-induced rat model of irritable bowel syndrome (IBS), a chronic functional digestive tract disorder marked by immune and inflammatory-related disturbances of central nervous and peripheral intestinal systems, which is often associated with mood disorders including depression and anxiety. Consequently, memory impairment, anxiety and depression behavioral indicators, and cerebral oxidative stress biomarker dynamics were evaluated in a multifactorial heterotypic stress-exposed IBS rats after 6-day gavage with polyphenolic C. americanum extract (100 mg/kg body weight). Y-maze, elevated plus maze, and forced swimming tests were used for assessing behavioral responses. Administration of the extract exhibited significant anxiolytic and antidepressant-like effects coupled with significantly increased temporal lobe antioxidant enzyme specific activity (superoxide dismutase and glutathione peroxidase) and decreased malondialdehyde levels, a well-known lipid peroxidation marker. Furthermore, linear regression statistical analyses showed significant correlations between the oxidative stress parameters and behavioral tests. In conclusion, our results suggest that the administration of Chrysanthellum americanum polyphenolic extract could ameliorate mood and cognitive disturbances related to stress-induced in an IBS rat model. This could be also related to cerebral oxidative stress status attenuation.

Alkaloid-Rich Crude Extracts, Fractions and Piperamide Alkaloids of Piper guineense Possess Promising Antibacterial Effects.

Piper guineense is a food and medicinal plant commonly used to treat infectious diseases in West-African traditional medicine. In a bid to identify new antibacterial compounds due to bacterial resistance to antibiotics, twelve extracts of P. guineense fruits and leaves, obtained by sequential extraction, as well as the piperine and piperlongumine commercial compounds were evaluated for antibacterial activity against human pathogenic bacteria. HPLC-DAD and UHPLC/Q-TOF MS analysis were conducted to characterize and identify the compounds present in the extracts with promising antibacterial activity. The extracts, with the exception of the hot water decoctions and macerations, contained piperamide alkaloids as their main constituents. Piperine, dihydropiperine, piperylin, dihydropiperylin or piperlonguminine, dihydropiperlonguminine, wisanine, dihydrowisanine and derivatives of piperine and piperidine were identified in a hexane extract of the leaf. In addition, some new piperamide alkaloids were identified, such as a piperine and a piperidine alkaloid derivative and two unknown piperamide alkaloids. To the best of our knowledge, there are no piperamides reported in the literature with similar UVλ absorption maxima and masses. A piperamide alkaloid-rich hexane leaf extract recorded the lowest MIC of 19 µg/mL against Sarcina sp. and gave promising growth inhibitory effects against S. aureus and E. aerogenes as well, inhibiting the growth of both bacteria with a MIC of 78 µg/mL. Moreover, this is the first report of the antibacterial activity of P. guineense extracts against Sarcina sp. and E. aerogenes. Marked growth inhibition was also obtained for chloroform extracts of the leaves and fruits against P. aeruginosa with a MIC value of 78 µg/mL. Piperine and piperlongumine were active against E. aerogenes, S. aureus, E. coli, S. enterica, P. mirabilis and B. cereus with MIC values ranging from 39–1250 µg/mL. Notably, the water extracts, which were almost devoid of piperamide alkaloids, were not active against the bacterial strains. Our results demonstrate that P. guineense contains antibacterial alkaloids that could be relevant for the discovery of new natural antibiotics.

An ethnobotanical survey and antifungal activity of Piper guineense used for the treatment of fungal infections in West-African traditional medicine

Ethnobotanical relevancePiper guineense occurs commonly in West Africa where it is used for fungal infections instead of the costly and not always accessible conventional antifungals. Fungal, yeast-based diseases are common in West-Africa especially among those living with HIV/AIDS, and thus this study was performed in Imo state, South-Eastern Nigeria, where P. guineense is predominantly used for the treatment of fungal diseases, such as skin rashes, oral thrush and vaginosis. Aim of studyThe scarce number of previous studies on the documentation of the traditional uses of P. guineense extracts for the treatment of fungal infections in Nigeria prompted this survey. The investigation focused on how traditional healers recognize and diagnose fungal infections, how P. guineense is collected, on the various parts used for the treatments, methods of preparations, administrations and treatments. In addition, an in vitro antifungal screening of P. guineense fruit and leaf extracts of various polarities, and piperine and piperlongumine, representing the main constituents in these extracts, were performed. MethodsA house to house ethnobotanical survey was conducted using questionnaires. Twenty traditional medical practitioners (TMP) and herb sellers from ten villages were interviewed. Four human pathogenic strains of yeast and Cryptococcus neoformans, a yeast-like basidiomycete causing meningitis in immunocompromised individuals, were used for the antifungal screening. ResultsThe traditional medical practitioners (TMP) and herb sellers explained that the leaves and fruits are the most commonly used plant parts for the treatments. The oral intake of the extracts in locally produced bamboo alcohol (Kai-kai) is the most common method of administration. In accordance with these recorded traditional uses, we found that extracts of P. guineense were growth inhibitory against the fungal strains with MIC values ranging from 39 to 2500 µg/mL. The lowest MIC value of 39 µg/mL was recorded for a methanol fruit extract against Candida albicans, C. glabrata and C. tropicalis. In addition, ethanol and hexane fruit extracts were effective against the growth of C. albicans and C. glabrata, respectively, with a MIC of 78 µg/mL. Piperlongumine and piperine were active against C. albicans with MIC values of 39 and 78 µg/mL respectively. ConclusionP. guineense fruit and leaf extracts, as well as their piperamide alkaloid constituents piperine and piperlongumine, have interesting antifungal properties and could have potential as new antifungal scaffolds. Our results warrant further in-depth investigations to isolate and characterize piperamide alkaloids and other compounds responsible for the antifungal activity in the extracts.

Phytochemical characterization of Tabernanthe iboga root bark and its effects on dysfunctional metabolism and cognitive performance in high-fat-fed C57BL/6J mice.

Preparations of the root bark of Tabernanthe iboga have long been used in Central and West African traditional medicine to combat fatigue, as a neuro-stimulant in rituals, and for treatment of diabetes. The principal alkaloid of T. iboga, ibogaine, has attracted attention in many countries around the world for providing relief for opioid craving in drug addicts. Using a plant metabolomics approach, we detected five phenolic compounds, including 3-O-caffeoylquinic acid, and 30 alkaloids, seven of which were previously reported from T. iboga root bark. Following a report that iboga extracts contain insulinotropic agents, we aimed to determine the potential alleviating effects of the water extract of iboga root bark on high-fat diet (HFD)-induced hyperglycemia as well as its effects on cognitive function in male C57BL/6J mice. Feeding a HFD to mice for 10 weeks produced manifestations of metabolic syndrome such as increased body weight and increased plasma levels of glucose, triacylglycerols, total cholesterol, LDL-cholesterol, insulin, leptin, and pro-inflammatory mediators (IL-6, MCP-1, ICAM-1), as compared to mice fed a low-fat diet (LFD). Supplementation of HFD with iboga extract at ibogaine doses of 0.83 (low) and 2.07 (high) mg/kg/day did not improve these HFD-induced metabolic effects except for a reduction of plasma MCP-1 in the low dose group, indicative of an anti-inflammatory effect. When the HFD mice were tested in the water maze, the high-dose iboga extract caused hippocampus-dependent impairments in spatial learning and memory, as compared to mice receiving only a HFD.

Tannins, flavonoids and stilbenes in extracts of African savanna woodland trees Terminalia brownii, Terminalia laxiflora and Anogeissus leiocarpus showing promising antibacterial potential

Terminalia laxiflora, Terminalia brownii and Anogeissus leiocarpus are used as decoctions, macerations, infusions and fumigations in East and West African traditional medicine for treatment of infectious diseases and their symptoms. Using this ethnopharmacological information as a guideline for our research and owing to the fact that these species have not been subjected to in depth antibacterial and phytochemical studies, thirty-nine extracts of various polarities of the stem bark, stem wood and roots were studied for growth inhibitory effects against the human pathogenic bacteria Staphylococcus epidermidis, Staphylococcus aureus, Micrococcus luteus and Pseudomonas aeruginosa. Our results indicate that the studied species contain antibacterial compounds of a wide range of polarities. All polar root extracts of T. laxiflora and various polar extracts of T. brownii roots, including hot water decoctions, gave broad-spectrum antibacterial effects and low MIC values of 39μg/ml. The main ellagitannins in an ethyl acetate extract of the root of T. laxiflora were found to be corilagin and its derivative and punicalagin. A methanol extract of the roots of T. brownii contained methyl-(S)-flavogallonate and its derivative as the main identified ellagitannins. Moreover, both Terminalia species were found to contain ellagic acid xylopyranoside and methyl ellagic acid xyloside and pure ellagic acid was present in T. brownii. Pure punicalagin did not give as low MIC as an ethyl acetate extract of the roots of T. laxiflora, containing punicalagin as one of its main compounds, although this ellagitannin totally inhibited the growth of S. aureus at 125μg/ml and P. aeruginosa at 500μg/ml. Similarly, pure ellagic and gallic acid gave higher MIC values than the methanolic root extract of T. brownii against S. aureus and P. aeruginosa. Moreover, a Sephadex LH-20 fraction of the methanolic extract of the roots of T. brownii, enriched with methyl-(S)-flavogallonate and its isomer, gave higher MIC values than the crude methanolic extract. These results suggest that the polyphenols in the extracts might act synergistically with each other. A methanolic soxhlet extract of the roots of A. leiocarpus, containing ampelopsin, aromadendrin, taxifolin, pinosylvin and 4′-methylpinosylvin gave a low MIC value of 39μg/ml against all bacterial strains used in this investigation. Our results demonstrate that the roots, stem bark and stem wood of T. brownii, T. laxiflora and A. leiocarpus are rich sources of (new) antimicrobial compounds and justify the uses of these plants for treatment of infections in African traditional medicine.

Insulin and alpha amylase levels in alloxan-induced diabetic rats and the effect of Rothmannia hispida (K. Schum) Fagerl leaf extract

Objectives: Rothmannia hispida (R. hispida) is used in West African traditional medicine for the treatment of various ailments such as fever, dysentery, skin infections, abdominal pain and diabetes mellitus. To elucidate the pharmacological basis of the antidiabetic efficacy of this plant drug, the effect of R. hispida on insulin and alpha amylase levels were examined in alloxan-induced diabetic rats. Method: Diabetic rats were treated with leaf extract of R. hipida at dose levels of 250mg/kg and 500mg/kg respectively. The concentration of insulin in serum samples was estimated using Enzyme-Linked Immunoabsorbent Assay (ELISA) method using insulin kit (Syntron Bioresearch, USA), alpha amylase levels were estimated using routine biochemical procedures. Results: Treatment of alloxan diabetic rats with leaf extract of R. hipida significantly (p<0.001) reduced hyperglycaemia, significantly (p<0.001) attenuated alloxan-induced hypoinsulinaemia and significantly (p<0.01) increased alpha amylase levels compared with diabetic untreated rats. Conclusion: It is concluded that increased insulin secretion and/or increased alpha amylase synthesis sequel to enhanced liver glucose entry by Rothmannia hispida is proposed to be the mechanism by which this herbal plant exhibits its antidiabetic effect.

Bioassay-Guided Fractionation of a Leaf Extract from Combretum mucronatum with Anthelmintic Activity: Oligomeric Procyanidins as the Active Principle.

Combretum mucronatum Schumach. & Thonn. is a medicinal plant widely used in West African traditional medicine for wound healing and the treatment of helminth infections. The present study aimed at a phytochemical characterization of a hydroalcoholic leaf extract of this plant and the identification of the anthelmintic compounds by bioassay-guided fractionation. An EtOH-H2O (1:1) extract from defatted leaves was partitioned between EtOAc and H2O. Further fractionation was performed by fast centrifugal partition chromatography, RP18-MPLC and HPLC. Epicatechin (1), oligomeric proanthocyanidins (OPC) 2 to 10 (mainly procyanidins) and flavonoids 11 to 13 were identified as main components of the extract. The hydroalcoholic extract, fractions and purified compounds were tested in vitro for their anthelmintic activity using the model nematode Caenorhabditis elegans. The bioassay-guided fractionation led to the identification of OPCs as the active compounds with a dose-dependent anthelmintic activity ranging from 1 to 1000 μM. Using OPC-clusters with a defined degree of polymerization (DP) revealed that a DP ≥ 3 is necessary for an anthelmintic activity, whereas a DP > 4 does not lead to a further increased inhibitory effect against the helminths. In summary, the findings rationalize the traditional use of C. mucronatum and provide further insight into the anthelmintic activity of condensed tannins.

Erythroivorensin: A novel anti-inflammatory diterpene from the root-bark of Erythrophleum ivorense (A Chev.)

The stem- and root-bark of Erythrophleum ivorense (A Chev., family, Fabaceae) are routinely employed in the West African traditional medicine to treat inflammation and a variety of other disease conditions. Although the chemistry and pharmacology of cassaine-type diterpene alkaloids isolated from the stem-bark of the plant are fairly established, the root-bark has not yet been investigated. In the present study, the crude aqueous-alcohol extract of the root-bark was demonstrated to display a time- and dose (30–300mg/kg p.o.)-dependent anti-inflammatory effect in chicks. Comprehensive chromatographic analysis coupled with spectroscopic and X-ray study further allowed the assignment of one of the major anti-inflammatory constituents as a novel cassaine-type diterpene, erythroivorensin. The other major constituents were known anti-inflammatory compounds: a triterpene, betulinic acid and a flavonoid, eriodictyol. The dose (10–100mg/kg p.o.)-dependent anti-inflammatory effects of the three compounds were either comparable or more significant than the positive control, diclofenac.

Ameliorative Effects of Ethanolic Leaf Extract of Palisota hirsuta K. Schum (Commelinaceae) on Vincristine-Induced Neuropathic Pain in rats

Vincristine-induced neuropathy is a major dose-limiting side effect of cancer chemotherapy and thus effective therapeutic strategy is required. The present study utilized a rodent model of neuropathy to determine whether an ethanolic leaf extract of Palisota hirsuta (PHE), a plant widely used in West African traditional medicine for pain management and CNS disorders, could attenuate vincristine-induced neuropathic pain. Neuropathic pain was induced by injecting rats intraperitoneally with vincristine (0.1 mg kg-1 day-1 in two 5-day cycles with a two-day break). Randall-Selitto Paw Pressure, Hargreaves, cold water (4-5˚C) and Von Frey Filaments tests were performed. These tests were used to assess the degree of mechanical hyperalgesia, thermal hyperalgesia and cold and tactile allodynia respectively as an index of peripheral and central pain sensation. Oral administrations of PHE (30-300 mg kg-1) significantly and dose-dependently ameliorated vincristine-induced pain-related behaviors. It significantly reduced both mechanical and thermal hyperalgesia and completely reversed vincristine-induced tactile allodynia at 100 and 300 mg kg-1 after 24 h. It however showed little effect on cold allodynia. These effects were similar to that of the gabapentin-treated group. In conclusion, oral administration of an ethanolic leaf extract of Palisota hirsuta attenuates pain-related behavior in vincristine-induced neuropathic pain model

Acute oral toxicity and brine shrimp lethality of Elaeis guineensis Jacq., (oil palm leaf) methanol extract.

Elaeis guineensis (Arecaceae) is widely used in West African traditional medicine for treating various ailments. An evaluation on the toxicity of extracts of this plant is crucial to support the therapeutic claims. The acute oral toxicity and brine shrimp lethality of a methanolic extract of this plant was tested. Oral administration of crude extract at the highest dose of 5,000 mg/kg resulted in no mortalities or evidence of adverse effects, implying that E. guineensis is nontoxic. Normal behavioral pattern, clinical signs and histology of vital organs confirm this evidence. The E. guineensis extracts screened for toxicity against brine shrimp had 50% lethal concentration (LC50) values of more than 1.0 mg/mL (9.00 and 3.87 mg/mL, at 6 and 24 h, respectively), confirming that the extract was not toxic. Maximum mortalities occurred at 100 mg/mL concentration while the least mortalities happened to be at 0.195 mg/mL concentration. The results of both tests confirm that E. guineensis is nontoxic and hence safe for commercial utilization.

Hepatoprotective and in vivo antioxidant effects of Byrsocarpus coccineus Schum. and Thonn. (Connaraceae)

Ethnopharmacological relevance The leaf decoction of Byrsocarpus coccineus (Connaraceae) is drunk for the treatment of jaundice in West African traditional medicine. Aim of the study To investigate the hepatoprotective and in vivo antioxidant effects of Byrsocarpus coccineus in carbon tetrachloride (CCl 4)-induced hepatotoxicity in rats. Materials and methods Group allotment in this study included vehicle, CCl 4, Byrsocarpus coccineus 1000 mg/kg alone, Byrsocarpus coccineus 200, 400, and 1000 mg/kg + CCl 4 and Livolin ® 20 mg/kg + CCl 4, and treatment was carried out accordingly. On the 7th day, rats were sacrificed and blood was withdrawn by cardiac puncture. The levels and activities of serum biochemical parameters and antioxidant enzymes were then assayed using standard procedures. Results CCl 4 significantly ( P < 0.05) increased the levels of ALT and AST and reduced total protein. In CCl 4 treated animals, Byrsocarpus coccineus (200, 400, and 1000 mg/kg) dose-dependently and significantly decreased ALT, AST and ALP levels with peak effect produced at the highest dose. Conversely, Byrsocarpus coccineus produced significant increases in albumin and total protein levels. The standard drug produced significant effects in respect of ALT (↓), albumin (↑), and total protein (↑). CCl 4 also produced significant ( P < 0.05) reductions in the activity of catalase, SOD, peroxidase and GSH, and conversely increased MDA level. Byrsocarpus coccineus produced significant and dose-dependent reversal of CCl 4-diminished activity of the antioxidant enzymes and reduced CCl 4-elevated level of MDA. The standard drug also significantly increased CCl 4-diminished antioxidant enzymes activity and reduced CCl 4-elevated MDA level. In general, the effects of the standard drug were comparable and not significantly different from those of Byrsocarpus coccineus. Conclusion The results obtained in this study suggest that the aqueous leaf extract of Byrsocarpus coccineus possesses hepatoprotective and in vivo antioxidant effects. This finding justifies the use of this preparation in West African traditional medicine for the treatment of liver disease.

Antiplasmodial activity and cytotoxicity of plants used in West African traditional medicine for the treatment of malaria

Eighteen plants originating from Ivory Coast were selected by ethnobotanical survey as plants commonly used by traditional healers for the treatment of malaria. Extracts of these plants were tested on two strains of Plasmodium falciparum: FcM29-Cameroon (chloroquine-resistant strain) and a Nigerian chloroquine-sensitive strain. The powdered plants were used to prepare three kinds of extracts: by decoction in water, in ethanol (95%) and in pentane. A radioactive micromethod allowed the evaluation of the antiplasmodial in vitro activity of the extracts on P. falciparum. Concentrations inhibiting 50% of the parasite growth (IC 50) ranged from 18 μg/ml to more than 500 μg/ml for aqueous and ethanol extracts and from 4.3 μg/ml to more than 500 μg/ml for pentane extracts. Cytotoxicity was estimated on A375 melanoma cells and a cytotoxicity/antiplasmodial index (CAR) was calculated for each extract, ranging from 1 to 10. The pentane extracts of Cola caricaefolia and Uvaria afzelii, which revealed the strongest antiplasmodial activity had CAR values of about 10.

Antiplasmodial activity of plant extracts used in west African traditional medicine

Five plants originating from Ivory Coast were selected after an ethnobotanical survey, Alchornea cordifolia, Mitragyna inermis, Nauclea diderrichii, Pterocarpus santalinoides, and Terminalia glaucescens. Traditional healers for the treatment of malaria commonly used these plants. Extracts of these plants were tested on three strains of Plasmodium falciparum, FcB1-Colombia and FcM29-Cameroon (chloroquine-resistant strains) and a Nigerian chloroquine-sensitive strain. Extracts were obtained by preparing decoction in water of the powdered plant, the technique used by most of the traditional healers. A radioactive micromethod allowed the evaluation of the in vitro activity of the extracts on P. falciparum. Concentrations inhibiting 50% of the parasite growth (IC 50) ranged from 2.34 to more than 500 μg/ml according to the plant. For the most active plants ( A. cordifolia and T. glaucescens) ethanol and pentane extracts were made and tested. The IC 50 values obtained for these extracts ranged from 0.35 to 43.40 μg/ml. The stage specificity of the ethanol extracts of A. cordifolia and T. glaucescens and pentane extract of T. glaucescens on the parasite erythrocytic cycle were determined. The ethanol extract of T. glaucescens showed its highest activity at the transition from the trophozoite to the schizont stages. Cytotoxicity was estimated on human fibroblasts (HeLa) cells and a cytotoxicity/antiplasmodial index was calculated, it ranged between 5 and 21, and the best antiplasmodial extract ( T. glaucescens ethanol extract) had the higher index (>20).

Anti-Toxoplasma activity of vegetal extracts used in West African traditional medicine.

Both Toxoplasma gondii and Plasmodium are Apicomplexan protozoa that share common metabolic pathways and potential drug targets. The objective of this study was to examine the anti-Toxoplasma activity of nine West African plants with known activity against P. falciparum. The extracts were obtained from parts of plant commonly used, by most traditional healers, in the form of infusion or as water decoction. The in vitro activity of plant extracts on T. gondii was assessed on MRC5 tissue cultures and was quantified by enzyme-linked immunoassay. Aqueous extracts from Vernonia colorata were found to be inhibitory for Toxoplasma growth at concentrations > 10 mg/L, with an IC50 of 16.3 mg/L. A ten-fold gain in activity was obtained when organic solvents such as dichloromethane, acetone or ethanol were used to extract V. colorata's active principles. These extracts were inhibitory at concentrations as low as 1 mg/L, with IC50 of 1.7, 2.6 and 2.9 mg/L for dichloromethane, acetone and ethanol extracts respectively. These results indicate a promising source of new anti-Toxoplasma drugs from V. colorata and African medicinal plants.