[Effects of Dacryodes edulis fruit oil on anxiety symptoms and cognitive performance in mice, after prolonged administration]. / Effets de l'huile des fruits de Dacryodes edulis sur les symptômes de l'anxiété et les performances cognitives chez la souris, après administration prolongée.

OBJECTIVE: To study the effects of prolonged administration of Dacryodes edulis (G. Don) H.J. Lam (HDE) fruit oil on the symptoms of anxiety and cognitive performance in mice. METHODS: Anxiolytic activity and effects of HDE (5 and 10 ml/kg) on cognitive performance were evaluated in male mice after oral administration for 45 days. Anxiolytic effects were investigated in open field test, elevated plus Maze and hole board test. The Morris Water Maze test was used to evaluate cognitive performance in mice. Efficacy of HDE (5 and 10 ml/kg) was compared with that of fluoxetine (2 mg/kg p.o). RESULTS: HDE decreases the total distance traveled, significantly increases the number of adjustments and the number of entries in the central area of open field. In the elevated cross labyrinth test, HDE increases the number of entries and the time spent in the open arms. HDE significantly increases the number of head insertion into the holes. In the Morris Water Maze test, HDE reduces latency before finding the platform and increases the time spent in the target quadrant. CONCLUSION: The results confirm anxiolytic effects and improved cognitive performance after prolonged oral administration of HDE in rodents.

Marker of coxsackievirus-B4 infection in saliva of patients with type 1 diabetes.

BACKGROUND: Coxsackieviruses B (CV-B) are enteroviruses that have been reported to play a role in the pathogenesis of type 1 diabetes. Enteroviral RNA was detected in the gut mucosa of patients. The mucosal immunity is an interconnected network; therefore, the response to enteroviruses possibly present in the gastrointestinal mucosa can be reflected by specific antibodies in the saliva. In the present study, the anti-CV-B neutralizing activity of saliva samples from patients with type 1 diabetes was investigated. METHODS: Saliva samples were collected from patients and controls of 3 countries, and plasma was obtained from some of them. The anti-CV-B activity of clinical samples was determined by neutralization of the cytopathic effect induced by challenging viruses in vitro and expressed as titre value. RESULTS: Overall prevalence and levels of anti-CV-B4 activity of saliva were higher in patients (n = 181) than in controls (n = 135; P = .0002; titre values ≥ 16: odds ratio = 4.22 95% CI: 1.90-9.38 P = .0002). It has been shown that IgA1 played a role in this activity. There was no correlation between the saliva and the plasma anti-CV-B4 neutralizing activity. The neutralizing activity of saliva against CV-B1, CV-B2, CV-B3, and CV-B5 existed rarely, if at all. Increased levels of anti-CV-B4 activity were observed all along a 4 year follow-up period in patients but not in matched controls (P = .01). CONCLUSION: There is an anti-CV-B4 activity in saliva of patients with type 1 diabetes that may be a useful marker to study the role of CV-B in the pathogenesis of the disease.

Analgesic and anti-inflammatory effects of Cassia siamea Lam. stem bark extracts.

AIM OF THE STUDY: The present study was carried out to investigate analgesic and anti-inflammatory activities of Cassia siamea Lam stem bark extracts. We have also determined the cytotoxicity of each extract. MATERIALS AND METHODS: C. siamea, a widespread medicinal plant traditionally used in sub-Saharan Africa, was collected in Congo Brazzaville. Stem bark was extracted with petroleum ether (CSE1), chloroform (CSE2), ethanol (CSE3) and water (CSE4). Analgesic, anti-inflammatory and antipyretic activities of these extracts were assessed in rats with hot plate test, paw pressure and carrageenan induced paw oedema. Cytotoxicity was assessed against KB and Vero cells. RESULTS: At the doses used (100, 200, and 400mg/kg) ethanol and water extracts showed significant and dose-dependent analgesic and anti-inflammatory effects. None of the extracts had cytotoxic activity on KB and Vero cell lines and the most active extracts (CSE3 and CSE4) had no acute toxicity. CONCLUSIONS: The study highlighted the analgesic and anti-inflammatory of C. siamea stem bark. Four major families of compounds present in the plant may explain these activities: triterpenes (lupeol, oleanolic acid, ursolic acid, friedelin, betulin), flavonoids (apigenin, kaempferol, luteolin), anthraquinones (emodin), phytosterols (stigmasterol, beta-sitosterol).

Comparative chemical and analgesic properties of essential oils of Cymbopogon nardus (L) Rendle of Benin and Congo.

The chemical and analgesic comparison of essential oils of Cymbopogon nardus (L) Rendle of Benin and Congo was investigated. The chemical analysis wa carried out by using GS/MS for identification of components of the two essential oils while acetic acid-induced writhings, hot plate and tail flick test models were used for analgesic activity. The results showed that the two essential oils exhibited comparable activity on acetic acid-induced writhings, however, the essential oil of Benin induced more significant effect on hot plate model while the Congolese specie showed more effect in the tail flick test. These observations could be explained by some qualitative and/or quantitative differences observed between the constituents of the two essential oils studied.

Chemical composition and pharmacological activity of essential oil of Canarium schweinfurthii.

The essential oil obtained by hydrodistillation of the resin of Canarium schweinfurthii growing in Central African Republic, was analysed by GC and GC/MS and its analgesic and antiinflammatory effects were studied. The major constituents of the essential oil were octylacetate (60%) and nerolidol (14%). At the doses of 1, 2 and 3 ml/kg i.p. essential oil shows a significant analgesic effect using acetic acid-induced writhing and hot plate methods. However, its was unable to reduce inflammatory process in cotton pellet induced granuloma method.

Evaluation of analgesic effect of Datura fastuosa leaves and seed extracts.

The aqueous extracts of Datura fastuosa leaves and seeds were evaluated for the analgesic effect on acetic acid-induced writhing and hot plate reaction in mice. According to the results, D. fastuosa leaves and seeds extracts at oral doses of 400 and 800 mg/kg are effective as analgesic. The analgesic activity of leaf extract is reduced by naloxone but not that of seed extract.

Analgesic, antipyretic and anti-inflammatory effects of essential oil of Lippia multiflora.

The essential oil of Lippia multiflora Moldenke (Verbenaceae) produced by conventional hydrodistillation was analyzed and studied for its analgesic, antipyretic and anti-inflammatory activities in rats and mice. At the doses used (2, 4 and 8 ml/kg o.s.) the essential oil of L. multiflora showed significant and dose-dependent analgesic effect on acetic acid-induced writhing in mice. Only the dose of 8 ml/kg of essential oil, antagonized hyperexia induced by brewer's yeast. No effect on granuloma formation was observed.

[Psychopharmacological properties of crude extract and essential oil of Lippia multiflora]. / Propriétés psychopharmacologiques de l'extrait brut et de l'huile essentielle de Lippia multiflora.

Psychopharmacological properties of crude extract and essential oil of Lippia multiflora (Lm), a verbenacea of african traditional pharmacopea were investigated in rat using classical methods. The extract of Lm is constituted by an infusion of dried leaves. The essential oil is obtained by hydrodistillation of the dried leaves of Lm with a yield of 0.6%. A dilution of 1% is realised with distilled water and the dose of 2 ml/kg of this solution was chosen for this study. The wistar rats of both sexes weighting between 150 and 250 g are used. Animal's behaviour is observed macroscopically for 12 hours. The spontaneous motor activity is appreciated by method of Martin et al. slightly modified. The number of squares jumped by animals in a rectangular cage is determined in ten minutes. The traction test which measures the time necessary for restoration of posterior paws of rat on metallic bar and the duration of pentobarbital sleeping are used for evaluation of muscle relaxant and sedative effects, respectively. The effects of the two preparations of Lm on apomorphin stereotypies and hypothermia are used to investigate the eventual neuroleptic or antidepressant activity. Analgesic property is evaluated by using acetic acid method. The results are expressed as mean +/- SEM. Data are analysed by using the Dunnett's test. A probability level of 0.05 or less was considered to be stalistically significant. The two preparations of Lm at the doses used are well tolerated by rats. No macroscopic difference is observed in behavioural of control and treated groups. Crude extract and essential oil:--does not modify a spontaneous motor activity: control: 45.00 +/- 5.63; crude extract of Lm: 31.00 +/- 5.63; essential oil of Lm: 28.00 +/- 7.62; diazepam 4 mg/kg: 23.80 +/- 5.27 (P < 0.05);--caused an increase of the time necessary for the restoration of paws on the metallic bar in the traction test: control 1.20 +/- 0.25 sec; crude extract of Lm 5.60 +/- 0.57 sec (P < 0.01), essential oil of Lm. 3.60 +/- 0.57 sec (P < 0.01) diazepam 3.60 +/- 0.57 sec (P < 0.01). The differences between the results obtained with crude extract, essential oil and diazepam are significant;--caused a reduction of abdominal cramps induced by acetic acid, control: 26.80 +/- 0.41; crude extract of Lm: 17.00 +/- 1.45 (P < 0.01); essential oil of Lm: 9.20 +/- 1.91 (P < 0.01) and acetylsalicylic acid (Aspegic*) 25 mg/kg 5.40 +/- 1.25 (P < 0.01). The differences is significant between essential oil and crude extract (P < 0.05) but no significant difference is observed between essential oil and acetylsalicylate of lysin. No activity of the two preparations is observed on apomorphin stereotypia and hypothermia comparatively with haloperidol 4 mg/kg and clomipramin 16 mg/kg respectively. Those results confirm the tranquillizer and analgesic activities of Lm and reveal that the crude extract would be more muscle relaxant and the essential oil more analgesic.

[Psychopharmacologic properties of Lippia multiflora]. / Propriétés psychopharmacologiques du Lippia multiflora.

Lippia multiflora (L.m.) is a verbenacea used in Congo as conventional tea decoction. No traditional indication is known in this country. Nevertheless, in Ghana the plant is used for the treatment of arterial hypertension. The aim of this study is to investigate the psychotropic activity of the aqueous extract of L.m. using the classical tests of experimental psychopharmacology. The extract of L.m. is constituted by lyophilisated powder obtained from an infusion of dried leaves. Different doses are prepared: 200, 400, 600, 800, 1,000 and 1,200 mg/kg dissolved in 1 ml of NaCl 0.9%. L.m. is administered by intraperitoneal or oral route. The wistar rats of both sexes, weighing between 150-200 g, are used. Animal's behaviour is observed macroscopically. The spontaneous motor activity is appreciated by using the number of squares crossed by animal with the four paws in ten minutes (Martin and al. method slightly modified). The rectal temperature is measured. The effect of L.m. on stereotypies induced by apomorphin and anesthesia induced by phenobarbital are studied. The traction test is used to investigate the muscle relaxant effect of L.m. and analgesic activity is evaluated by using acetic acid and hot plate methods by comparison with diazepam 2 and 4 mg/kg. Fischer-t test is used for the statistical analysis of results. L.m. is well tolerated by rats. No mortality is observed with the doses used. So the doses of 200, 400 and 600 mg/kg were selected for experiments. At theses doses L.m. caused: a precocious ataxia, a sedation, a ptosis and a yellow coloration of urines, these effects are dose dependent; a significant reduction of spontaneous motor activity: control 61.60 +/- 6.48, L.m. 200: 16.40 +/- 5.68 (P < 0.01), L.m. 400: 12.20 +/- 2.01 and L.m. 600: 9.60 +/- 1.90 (P < 0.01); no modification of rectal temperature and apomorphin stereotypies; a reduction of sleep latence: control 22.40 +/- 1.89 min, L.m. 200: 17.20 +/- 2.74 min (P < 0.01), L.m. 400: 13.80 +/- 1.81 min (P < 0.01) and L.m. 600: 13.40 +/- 2.16 min (P < 0.01); a potentiation of phenobarbital anesthesia: L.m. 200: 209.80 +/- 29.58 min (N.S.), L.m. 400: 336.40 +/- 22.23 min (P < 0.01), L.m. 600: 342.20 +/- 16.28 min (P < 0.01) and control: 199.40 +/- 2.90 min; an increase at the dose of 400 mg/kg of the time necessary for the restoration of the paws to the metallic bar in the traction test: control; 0.8 +/- 0.1 s, L.m. 400: 7.04 +/- 2.29 s (P < 0.05); a reduction of abdominal cramps induced by acetic acid. This number is respectively 18.40 +/- 4.49 (P < 0.05); 15.00 +/- 2.90 (P < 0.01), 14.20 +/- 3.89 (P < 0.01), 11.60 +/- 4.75 (P < 0.01), 13.00 +/- 2.00 (P < 0.01) and 33.80 +/- 5.04 for L.m. 200 mg/kg, L.m. 400 mg/kg, L.m. 600 mg/kg, Diazepam 2 and 4 mg/kg and control; an increase of reaction time on the hot plate: L.m. 200: 3.26 +/- 0.46 s (N.S.), L.m. 400: 4.50 +/- 0.80 s (P < 0.01), L.m. 600: 10.50 +/- 1.56 s (P < 0.001), diazepam 2 mg/kg: 2.90 +/- 0.51 s (N.S.), diazepam 4 mg/kg: 5.90 +/- 1.09 s (P < 0.01) and control 2.10 +/- 0.26 s. Those results demonstrated that L.m. possess a tranquilizer and analgesic activities as Diazepam. But, anticonvulsant and anxiolytic tests are necessary to confirm the psychopharmacological profile of this medicinal plant.

[Analgesic effects of a raw extract of Ageratum conyzoïdes in the rat]. / Effets analgésiques d'un extrait brut d'Ageratum conyzoïdes chez le rat.

Ageratum conyzoïdes (AC) is a plant used in traditional medicine for mental and infection diseases, cephalgia, dyspnea, enteralgia and fever. The objective of this study is to investigate the antinoceptive properties of Ageratum conyzoïdes in the rat. The raw extract of AC is constituted by a lyophilisated powder obtained from leaves juice extract by using a crusher. A dilution of 1% in NaCl 0.9% is prepared with the lyophilisat. Several doses of this preparation; 25, 50, 100, 125, 150 mg/kg are injected intraperitonealy in animals. The wistar rats of both sexes weighting between 200-250 g are used for this study. Animal's behaviour is observed macroscopically; the spontaneous motor activity is measured by using Martin et al. method (1990), slightly modified. The number of squares crossed by animal is measured every ten minutes during thirty minutes. The rectal temperature is sampled and analgesic activity evaluated by the hot plate method and by the writhing syndrome induced by acetic acid. AC is compared here with morphine 7.5 mg/kg sc and control 0.9% NaCl ip. The student--Fisher t test is used for the statistical analysis of the results. The results obtained demonstrate that all doses equal or higher than 125 mg/kg cause mortality of rat. The doses of 50 and 100 mg/kg are selected for experiments. At these doses, AC cause: a precocious ataxia, a sedation and a slight ptosis. Six hours after injection, those effects disappear; a reduction of spontaneous motor activity.(ABSTRACT TRUNCATED AT 250 WORDS)