Ethnopharmacological evaluation of antioxidant, anti-angiogenic, and anti-inflammatory activity of some traditional medicinal plants used for treatment of cancer in Togo/Africa.

ETHNOPHARMACOLOGICAL RELEVANCE: Cancer is a multistep disease and its management is exceedingly expensive. Nowadays medicinal plants are gaining more attention in drug discovery and approximately 70% of anticancer drugs were developed from natural products or plants. A strong candidate from medicinal plant with anticancer potential should have four major properties: antioxidant, anti-inflammatory, anti-angiogenic, and cytotoxic activities. AIM OF THE STUDY: In order to assess Togolese traditional healer's claims about the anticancer potential of medicinal plants and obtain candidate plants for anticancer drug discovery, some species were selected from surveys and evaluated for their antioxidant, anti-inflammatory, anti-angiogenic and cytotoxic activities. METHODS: Four species, Cochlospermum planchonii (CP), Piliostigma thonningii (PT), Paullinia pinnata (PP), and Securidaca longipedunculata (SL) were selected and analyzed to detect the phytochemical components. The mentioned bioactivities were evaluated using in vitro, ex vivo and in vivo assays. RESULTS: Relative to SL extract, CP and PT have shown significantly high polyphenols and flavonoids content. The DPPH, FRAP, and TAC of the extracts revealed that CP, PT, and PP have a potent antioxidant effect compared to SL. MDA analysis revealed the same antioxidant activity as CP, PT and PP showed a minor MDA level. The egg albumin denaturation assay showed that IC50 of CP and PP was significantly higher than control (P < 0.05). In contrast, the Bovine Serum Albumin (BSA) results showed a nonsignificant effect (P > 0.05). Notably, SL extract was nonsignificant to control in both Egg Albumin and BSA. Furthermore, angiogenesis assay showed that SL at 50 µg/ml and PP at 100 µg/ml effectively reduced the number of blood vessels than control and showed a potent anti-angiogenic effect (2.7-fold and 2.5-fold, respectively, P < 0.05). No cytotoxicity on PBMC was reported for CP, PP, and PT up to 1000 µg/ml, whereas SL at 1000 µg/ml exhibit benign cytotoxicity (P < 0.0001). CONCLUSION: This study provided in vitro evidence supporting further evaluation on cancer cell lines and tumors in vivo.

Acute and Sub-Acute Toxicity Studies of Plumeria alba Linn. (Apocynaceae) Hydroalcoholic Extract in Rat.

Plumeria alba Linn (Apocynaceae) is used in Togolese traditional medicine to treat diabetes mellitus and wounds. The present investigation was carried out to evaluate the toxicity of hydroalcoholic extract of Plumeria alba roots in Sprague Dawley rats. The acute toxicity test was conducted by administering orally dose of 5 g/Kg. General behavior and mortality were examined for up to 14 days. The sub-acute toxicity test was performed by daily gavage at 250, 500 and 1000 mg/Kg for 28 days. Body weight and blood glucose were measured weekly. Hematological and biochemical parameters, relative organ weight were determined at the end of the 28 days administration. In acute study, no adverse effect of the extract was observed at 5.0 g/Kg. Sub-acute oral administration of the extract at the dose up to 1000 mg/Kg did not induce death or significant changes in body weight, relative weight of vital organs, hematological parameters and was not associated with liver and kidney toxicity.

Preliminary evaluation of the wound healing effect of Vitex doniana sweet (Verbenaceae) in mice.

Vitex doniana is traditionally used in Togo to treat various diseases including wounds. The aim of this work was to evaluate the efficiency of Vitex doniana on cutaneous wound healing. Wounds were induced in ICR mice divided into four groups as following: Group I received carbopol 974P NF empty gel, Groups II and III were treated topically with carbopol gel containing 2.5% and 5% of Vitex doniana extract. Group IV received Betadine® 10% as standard drug. The efficacy of treatment was evaluated by planimetry and histological analysis. We secondary used the gel containing Vitex doniana at 2.5% and the pure extract at 10 mg/ml on the model of ear edema induced by xylene. Skin toxicity test was performed with the gel containing Vitex doniana at 5% and the pure extract at 30 mg/ml. Vitex doniana at 5% and 2.5% provided better wound contraction (91.14% and 86.38%) at day 12 post-excision when compared to control (51.15%). The results of histological evaluation supported the outcome of excision wound model. Moreover Vitex doniana inhibited significantly edema induced by xylene when compared to control (p< 0.05). In skin toxicity test, no abnormal symptoms were developed over 14 day-time period. Vitex doniana inhibits the topical inflammation and accelerate cutaneous wound repair.

An ethnobotanical study of antimalarial plants in Togo Maritime Region.

BACKGROUND: Malaria continues to be of great concern in Togo, as it accounts for high mortality rates, principally in children. Although plant-based medicines are the only means in major malarious regions of the country, still very little is known about the medicinal plants and medical practices of the indigenous people. OBJECTIVE: The present study aimed to document the indigenous medicinal plant utilization for the management of malaria and related symptoms in Togo Maritime Region. METHODOLOGY: Fifty Traditional Healers (TH) were selected with the help leaders of Togolese Traditional Healers Associations and information on their knowledge on the use of plants for malaria therapeutic purposes was gathered using a semi-structured interviews. RESULTS: After enquiries, 52 plant species belonging to 49 genera and 29 families were recorded. The most represented families were Rubiaceae and Rutaceae with four species each. Traditional healers agreed more in the treatment of malaria (ICF=0.70), fever (ICF=0.33) and anemia (ICF=0.20). For the treatment of malaria, 38.46% (20/52) of the species cited in the study were of high fidelity level (FL=100%). The leaves (58.22%), leafy stem (33.78%) and fruits (8.52%) were the most used parts in concoctions. The main mode of preparation was decoction (69%) and the administration was essentially by oral route (79%) and body-bath (14%). CONCLUSION: The issue of the study showed that Togo Maritime Region TH have a good knowledge of antimalarial plants. However the study must be extend to the whole country to lead to innovative strategies in malaria control. Such results could be a starting point for in vitro antimalarial screenings.

[Effect of Morinda lucida Benth. (Rubiaceae) and Newbouldia leavis P. Beauv. (Bignoniaceae) on sickling of red blood cells]. / Effet de Morinda lucida Benth. (Rubiaceae) et de Newbouldia leavis P. Beauv. (Bignoniaceae) sur la falciformation.

The purpose of this study was to evaluate the In vitro anti-sickling activity of two plants widely used for treatment of sickle cell disease in Togo, i.e., Morinda lucida et Newbouldia leavis. A concentration-dependent decrease in the rate of sickling was observed after incubation of red blood cells with plant extracts and 2% sodium metabisulfite as compared to incubation with 0.9% NaCl. On samples with a SS blood genotype the inhibition rate of Morinda lucida was 17.30% at a concentration of 1 mg/ml and 92.31% at a concentration of 30 mg/ml. On samples with an AS blood genotype, the inhibition rate of Morinda lucida 48.10% at a concentration of 1 mg/ml and 99.34% at a concentration of 30 mg/ml. Using Newbouldia leavis the inhibition rates at concentrations of 1 mg/ml and 30 mg/ml were 15.66% and 90.42% respectively on samples with a SS blood genotype and 64.03% and 99.02% respectively on samples with an AS blood genotype. The study protocol appeared to be adequate for both SS and AS blood genotypes since the Pearson correlation coefficient between rates measured on the two types of samples was 0.92 for Newuboulida and 0.89 for Morinda. These findings show that these two plants have clear-cut in vitro anti-sickling activity and support their use in traditional medicine.

In vitro effects of crude extracts of Parkia biglobosa (Mimosaceae), Stereospermum kunthianum (Bignoniaceae) and Biophytum petersianum (Oxalidaceae) on corticosteroid secretion in rat.

Previous studies conducted in guinea pig, rat and rabbit have revealed that crude extracts from Parkia biglobosa, Stereospermum kunthianum and Biophytum petersianum exert hypotensive and/or hypoglycemic activities. Since corticosteroids are involved in the control of arterial blood pressure and glycemia, we have investigated the possible effects of these plant extracts on rat adrenal tissue in vitro. Short-term administration of crude semi-ethanolic extracts of P. biglobosa and S. kunthianum to perifused rat adrenal tissue did not induce any significant changes in corticosteroid output. Conversely, the B. petersianum extract caused a dose-dependent increase in corticosterone and aldosterone secretion. Repeated infusions or prolonged administration of B. petersianum extract did not produce any apparent attenuation of the steroid response. Altogether, these data indicate that a semi-ethanolic extract of B. petersianum dose-dependently stimulates corticosterone and aldosterone secretion in rat without any desensitization phenomenon.

[Anti-cholinergic effect of Pluchea ovalis (pers.) Dc. (asteraceae) root extract on isolated Wistar rat tracheae]. / Effet anti-cholinergique de la racine de Pluchea ovalis (pers.) Dc. (asteraceae) sur la trachée artère de rat in vitro.

Ethanolic extract of Pluchea ovalis roots inhibit acetylcholine-induced bronchoconstriction observed in asthma. To understand the mechanism of P. ovalis root extract on airway smooth muscle contraction, we investigated the anti-cholinergic effect of the ethanolic extract on isolated isolated tracheae of the Wistar rat. For this purpose, three experimental conditions of incubation were used: idomethacin, indomethacin+propranolol or indomethacin+propranolo+ promethazine. The extract was applied in all three conditions at 0.25 mg/ml for 10 minutes prior to cumulative doses of acetylcholine (10(-8) to 5.10(-4) g/ml). The extract reduced acetylcholine-induced contraction and could have an antagonistic effect on muscarinic receptors of the rat trachea.