Harquin Simplice Foyet

Methanolic extract of Hibiscus asper leaves improves spatial memory deficits in the 6-hydroxydopamine-lesion rodent model of Parkinson's disease.

ETHNOPHARMACOLOGICAL RELEVANCE While the Hibiscus asper Hook.f. (Malvaceae) is a traditional herb largely used in tropical region of the Africa as vegetable, potent sedative, tonic and restorative, anti-inflammatory and antidepressive drug, there is very little scientific data concerning the efficacy of this. AIM OF THE STUDY We investigated antioxidant activity and the effects of methanolic extract of Hibiscus asper leaves on neurological capacity of male Wistar rats subjected to unilateral 6-hydroxydopamine (6-OHDA)-lesion. MATERIALS AND METHODS Two model systems: 2,4-dinitrophenyl-1-picryl hydrazyl (DPPH) radical scavenging activity and β-carotene bleaching inhibition assay were used to measure the antioxidant activities of the plan extract. We also investigated the neuroprotective effect of methanolic extract of Hibiscus asper leaves (50 and 100 mg/kg) in male Wistar rats subjected to unilateral 6-hydroxydopamine (6-OHDA)-lesion rat model. RESULTS Methanolic extract of Hibiscus asper leaves showed potent antioxidant and free radical scavenging activity. Chronic administration of methanolic extract (50 and 100 mg/kg, i.p., daily, for 7 days) significantly reduce anxiety-like behavior and inhibit depression in elevated plus-maze and forced swimming tests, suggesting anxiolytic and antidepressant activity. Also, spatial memory performance in Y-maze and radial arm-maze tasks was improved, suggesting positive effects on memory formation. CONCLUSIONS Taken together, our results suggest that the methanolic extract of Hibiscus asper leaves have antioxidant effects and might provide an opportunity to management neurological abnormalities in Parkinsons disease conditions.

Neuroprotective effect of the methanolic extract of Hibiscus asper leaves in 6-hydroxydopamine-lesioned rat model of Parkinson's disease

ETHNOPHARMACOLOGICAL RELEVANCE While the Hibiscus asper Hook.f. (Malvaceae) is a traditional herb largely used in tropical region of the Africa as vegetable, potent sedative, tonic and restorative, anti-inflammatory and antidepressive drug, there is very little scientific data concerning the efficacy of this. MATERIALS AND METHODS The antioxidant and antiapoptotic activities of the methanolic extract of Hibiscus asper leaves (50 and 100 mg/kg) were assessed using superoxide dismutase (SOD), glutathione peroxidase (GPX) and catalase (CAT) specific activities, total glutathione (GSH) content, malondialdehyde (MDA) level (lipid peroxidation) and DNA fragmentation assays in male Wistar rats subjected to unilateral 6-hydroxydopamine (6-OHDA)-lesion. RESULTS In 6-OHDA-lesioned rats, methanolic extract of Hibiscus asper leaves showed potent antioxidant and antiapoptotic activities. Chronic administration of the methanolic extract (50 and 100 mg/kg, i.p., daily, for 7 days) significantly increased antioxidant enzyme activities (SOD, GPX and CAT), total GSH content and reduced lipid peroxidation (MDA level) in rat temporal lobe homogenates, suggesting antioxidant activity. Also, DNA cleavage patterns were absent in the 6-OHDA-lesioned rats treated with methanolic extract of Hibiscus asper leaves, suggesting antiapoptotic activity. CONCLUSIONS Taken together, our results suggest that the methanolic extract of Hibiscus asper leaves possesses neuroprotective activity against 6-OHDA-induced toxicity through antioxidant and antiapoptotic activities in Parkinsons disease model.

Anti-inflammatory and anti-arthritic activity of a methanol extract from Vitellaria paradoxa stem bark

Background: Vitellaria paradoxa is a traditional medicinal plant of Cameroon. Several studies on this plant have focused on the cosmetic profile of its fruits. The present study focuses on the anti-inflammatory potency of stem barks extract of this plant. Objective: The objective was to evaluate the effect of methanolic extract of V. paradoxa (VPME) stem barks on inflammatory response in rats. Materials and Methods: Anti-inflammatory effects of VPME were evaluated in acute and chronic (28 days) inflammation induced in Wistar albino rats. The effects on hyperalgesia and locomotors activity were also quantified. The relative weight of lymphoid organs was obtained as well as some hematological parameters. Results: In the carrageenan-induced inflammation, VPME (75 mg/kg) exhibited a significant (66.67%) inhibition after 1 h. On the complete Freund′s adjuvant-induced rheumatoid arthritis, VPME showed a significant protective effect with 8.12% inflammation against 25.00% for the control group after 2 days of the treatment. The extract (75 and 150 mg/kg) significantly reduced the score of arthritis with a maximum obtained on day 19 th of the experimentation. There was a significant increase in the reaction time of rats on the hot plate as well as the exploratory activities of the animals in the open field. This extract significantly prevented weight, hemoglobin and red blood cells losses, and spleen hypertrophy. A protective action against skin destruction and cartilage erosion was evident. Liquid chromatography-mass spectrometry analysis of the extract revealed the presence of catechins. Conclusions: These findings suggested that V. paradoxa may contribute to the reduction of the inflammatory response.

Antifertility and Fetotoxic Activities of Acanthus montanus Aqueous Extract in Wistar Rats

Acanthus montanus T. Anderson (Acanthaceae) possesses several medicinal properties; it is used in Cameroon as a folk medicine to treat pain, inflammation and threatened abortion. The aim of this study was to determine the effect of A. montanus aqueous extract on the estrous cycle pre- and postimplantation in rats and its mechanism of action. The estrous cycles of Wistar rats were monitored before, during and after oral administration of distilled water (control) or aqueous extract (62.5, 125, 250, 500, 1000 mg/kg/day). Furthermore, pregnant rats received the above doses of aqueous extract on days 1-6 (preimplantation) or 6-15 (postimplantation) of gestation and were sacrificed on day 8 or 20 of pregnancy, respectively. Moreover, aqueous extract (500 and 1000 mg/kg/day) was given to ovariectomized rats in the presence or absence of exogenously administered estrogen and/or progesterone and uterine weight and deciduoma count were evaluated. The extract, irrespective of dose, reversibly prolonged the metestrous and occasionally the diestrous stages of the estrous cycle. The extract did not alter the uterine wet weight or deciduoma count, suggesting a lack of estrogenic and progestational effects. At 1000 mg/kg/day, the extract caused appreciable preimplantation losses of 36.8 +/- 6.5% (P < 0.05), while none of the doses caused postimplantation losses. The extract also caused delayed fetal growth.

A new ursane triterpenoic acid and other potential anti-inflammatory and anti-arthritic constituents from EtOAc extracts of Vitellaria paradoxa stem bark.

OBJECTIVE Vitellaria paradoxa (shea tree) is used in traditional medicine for the treatment of various ailments, including, inflammation and fever. Therefore the present research investigates the anti-inflammatory and anti-rheumatic effects of V. paradoxa stem bark extracts in rats and the isolation and characterization of its active constituents. METHODS The anti-inflammatory activity of ethyl acetate extract of V. Paradoxa (VPEE) was evaluated by use of the carrageenan-induced paw oedema model in rats. Moreover, rheumatoid arthritis (RA) was induced by injection of Freunds Completed Adjuvant (FCA) into the subplantar surface of the hind paw of the male Wistar rats. Paw volume was measured plethysmometrically. Joint swelling was measured using electronic vernier caliper. Hot plate test was used to assess the effect of VPEE on hyperalgesia while open field was used to assess the locomotors activity. The relative weight of spleen, liver and thymus was obtained as well as some haematological parameters. Tibiotarsal joint was extracted for histopathology under light microscope. Chemical analysis was carried out by high resolution mass spectrometry and one and two-dimensional NMR techniques. RESULTS LC-MS analysis of the EtOAc extract revealed the presence of a new triterpenoid and several known compounds. The structure of the novel compound was elucidated by means of LC-MS and selected 1D and 2D-NMR experiments. The biological effects of ethyl acetate (VPEE), methanol (VPME) and water extracts (VPAE) of V. paradoxa were tested on carrageenan model of acute inflammation and FCA-induced rheumatoid arthritis animal model. In the carrageenan-induced inflammation, VPEE (150 mg/kg) significant (66.67%) inhibited the first (after 1h) and the second phase (4-6h) of edema formation. On the Complete Freunds adjuvant-induced rheumatoid arthritis, VPEE at the same dose showed a significantly protective effect. On days 19-28th of treatment, the maximum inflammatory percentage was between 9.60 and 8.91% for the VPEE compared to 30.91-24.29% for the controls. All the extracts significantly reduced the score of arthritis but the maximal reduction was obtained with the VPEE on day 24th of the experimentation. The altered haematological parameters in the arthritic rats were significantly recovered to near normal by the treatment with VPEE at the dose of 150 mg/kg. Further histological studies revealed the anti-arthritic activity by preventing cartilage destruction of the arthritic joints of adjuvant arthritic rats. The spleen hypertrophy induced by the FCA was also significantly inhibited. CONCLUSION These findings provide pharmacological basis for the application of the VPEE in inflammatory disorders.

Antioxidant activity and phytochemical constituent of two plants used to manage foot and mouth disease in the Far North Region of Cameroon.

Aim: Plants used in the Far North Region of Cameroon by livestock farmers to manage foot and mouth disease (FMD) in cattle and the phytochemical composition and antioxidant potentials of two of them (Boscia senegalensis [BS] and Tapinanthus dodoneifolius [TD]) were investigated in this study. Materials and Methods: Ethno veterinary data were collected from 325 livestock farmers using semi-structured interviews from September 2011 to April 2012. The 2,2-diphenyl-picrylhydrazyl radical scavenging activity and total phenolic content (TPC) were first performed with five different solvents to choose the best extract of each plant based on these two factors. To achieve our aim, the ferric iron reducing activity, hydroxyl radical scavenging activity (HRSA), free radical scavenging activity (FRSA), vitamin E and iron content were analyzed on extracts selected using current techniques. Results: The results showed that 12 plants of 8 different families are regularly used by farmers to manage FMD. It also demonstrated that acetone extract of TD and methanolic extract of BS are the extracts which showed the best total antioxidant activity (AA) and the best TPC. In general, TD show the best AA during the HRSA and FRSA analysis compared with BS. Similarly, TD content more phenolic compounds and tannins than BS. Both plants contain proteins, saponins, tannins, phenols, alkaloid, and polyphenols which are known to have many biological activities. Conclusion: These results support the AA of both plants and can justify their use by herders to treat FMD which is often followed by many secondary diseases.

Anxiolytic and Antidepressant-Like Effects of the Aqueous Extract of Alafia multiflora Stem Barks in Rodents

The present study examined the anxiolytic and antidepressant effects of the aqueous extract of Alafia multiflora Stapf (AM) stem barks (150 and 300 mg/kg, 7 days administration) on rats and mice, using experimental paradigms of anxiety and depression. In the open field, the aqueous extract increased significantly the number of center square crossed and the time spent at the center of the field as well as the rearing time, while the grooming time was reduced significantly. In the elevated plus maze, the aqueous extract increased the time spent and the number of entries in the open arms. All these effects were also completely reversed by flumazenil, an antagonist of benzodiazepine receptors and pindolol a β-adrenoceptors blocker/5-HT 1A/1B receptor antagonist. The time spent in the light compartment, the latency time, and the number of the light-dark transitions increased significantly in the light/dark exploration test after the treatment with AM. The extract was able to reduce significantly the immobility time and increase swimming as well as climbing duration. Taken together, the present work evidenced anxiolytic effects of the aqueous extract of AM that might involve an action on benzodiazepine-type receptors and an antidepressant effect where noradrenergic mechanisms will probably play a role.

Triterpenoids from the stem bark of Vitellaria paradoxa (Sapotaceae) and derived esters exhibit cytotoxicity against a breast cancer cell line

A study of the chemical constituents of the stem bark of Vitellaria paradoxa (Sapotaceae) has resulted in the isolation and characterization of a new ursane-type triterpenoid, 2β,3β,19α-trihydroxyurs-12-en-28-oic acid (1), together with seven known compounds: betulinic acid (2), 1α,2β,3β,19α-tretrahydroxyurs-12-en-28-oic acid (3), β-sitosterol (7), sigmasterol (8), (-)-epicatechin (9), (+)-catechin (10) and quercetin (11). The structure of the novel, ursane-type acid 1 was elucidated on the basis of detailed spectroscopic analysis including IR, HRMS (ESI), 1D and 2D NMR and a comparison to previously described, related natural products. Preliminary cytotoxicity assays against the MDA-MB-231 breast cancer cell line indicated that betulinic acid 2 and its corresponding methyl ester 5 were the most active compounds tested with IC50 values of 19.9 μM (17.2–23.1 μM, 95% CI) and 32.9 μM (24.9–43.4 μM, 95% CI), respectively. Esterification of acids 1–3 afforded the corresponding methyl esters 4–6 for additional structure-activity relationship (SAR) analysis. In general, the activity against the MDA-MB-231 breast cancer cell line increased upon esterification of the triterpenoids screened.

Quality of veterinary pharmaceuticals and their use by pastoralists in the Far North Region of Cameroon

This study evaluates the quality of the veterinary drugs most frequently used in the Far North Region of Cameroon and describes how pastoralists use them to treat their cattle herds. High-performance liquid chromatography was used to identify and quantify the active ingredients in the drugs (penicillin G, levamisole, oxytetracycline, diminazene diaceturate, vitamin A, and vitamin E acetate) and gas chromatography mass spectrometry to determine if organic chemical contaminants were present. The results showed that 69% of surveyed pastoralists used veterinary medicines to treat common illnesses. In addition, the most commonly used medications (procaine penicillin G and oxytetracycline) were used in a manner inconsistent with the recommended dosage, frequency, duration, and withdrawal period by 98% of the pastoralists. However, contrary to previous studies, the quality of the medications used by pastoralists was generally good. The poor compliance with recommended treatment protocols was much more prevalent than use of poor quality medications and presents a potential for treatment failure, drug resistance of animal pathogens, and harmful drug residues in the human food supply, all of which have potentially negative consequences for animal and human health.

Effects of Ficus umbellata (Moraceae) Aqueous Extract and 7-Methoxycoumarin on Scopolamine-Induced Spatial Memory Impairment in Ovariectomized Wistar Rats

The present work was undertaken to evaluate the ability of F. umbellata aqueous extract and its major component 7-methoxycoumarin (MC) to improve scopolamine-induced spatial memory impairment in ovariectomized Wistar rats. For this to be done, 10 sham-operated and 30 postmenopausal-like rats were randomly distributed in eight groups (n = 5) and treated with distilled water (2 mL/250 g), estradiol valerate (1 mg/kg BW), piracetam (1.5 mg/kg BW), F. umbellata aqueous extract (50 and 200 mg/kg BW), or MC (1 mg/kg BW) for 21 consecutive days. Before and after the memory impairment with scopolamine (2 mg/kg BW), animals underwent behavioral evaluations on Y- and radial mazes. As results, age and ovariectomy did not induce significant changes in the reference memory errors. While age decreased working memory errors, ovariectomy increased it. The MC as well as F. umbellata extract significantly increased (p < 0.01) the percentage of spontaneous alternation and decreased (p < 0.001) working and spatial reference memory errors and anxiety parameters (rearing and grooming) in ovariectomized rats. MC significantly reduced (p < 0.05) the MDA level, but resulted in an increase in GSH level in brain homogenates. These results suggest that MC is endowed with neuroprotective effects and could account for the neuroprotective effects of F. umbellata in rats.