RESUMEN
Several lines say that a number of natural products, mostly plant based, have been claimed to cure male sexual dysfunction. One of such botanicals is Carpolobia alba G. Don which is used in Cameroon to treat erectile dysfunction and related male sexual debilities. However, the traditional claim has not been scientifically tested. Thirty adult male rats (five groups of six animals) were orally treated daily with distilled water, sildenafil citrate (positive control), 75, 150, 300 mg/kg of C. alba G. Don roots aqueous extract. The erection and ejaculation properties were recorded on the first, seventh and fourteenth day of treatment by following copulation settings: number of erections (NE), mount frequency (MF), intromission frequency (IF), ejaculation frequency (EF), mount latency (ML), intromission latency (IL), ejaculation latency (EL), average interval of copulation (AIC) and post-ejaculatory interval (PEI). The extract resulted in an improvement of copulation parameters through significant reduction (p < .001) of PEI, ML and IL and significant increase (p < .001) in the NE, MF, IF, EF, EL and AIC. These results indicate a pro-erectile and pro-ejaculatory potential of aqueous root extract of this plant in male rats.
Asunto(s)
Eyaculación/efectos de los fármacos , Erección Peniana/efectos de los fármacos , Extractos Vegetales/farmacología , Raíces de Plantas , Polygalaceae , Conducta Sexual Animal/efectos de los fármacos , Animales , Copulación/efectos de los fármacos , Masculino , RatasRESUMEN
Mature male albino Wistar rats (180-210 g) were given aqueous extract of dry seeds of Aframomum melegueta K. Schum (Zingiberaceae) by gastric intubation during periods of 8 and 55 days. This was performed in two doses: 115 and 230 mg kg(-1) during 8 days and 115 mg kg(-1) during 55 days. Control rats received distilled water during the same periods. The animals were sacrificed and their blood, as well as testis, epididymis, seminal vesicle and prostate were collected and analysed. Results showed a significant increase in testosterone in serum and testis, cholesterol in testis, α-glucosidase in epididymis and fructose in seminal vesicle after 8 days of treatment of A. melegueta-treated rats (115 and 230 mg kg(-1) ). Results also showed that levels of cholesterol in testis, α-glucosidase in epididymis and fructose in seminal vesicle increased by 93.34%, 83.44% and 62.78%, respectively, after 55 days of A. melegueta treatment. From these findings, it was concluded that the aqueous extract of A. melegueta increased the secretions of epididymis and seminal vesicle, which are accessory sex organs.
Asunto(s)
Reproducción/efectos de los fármacos , Zingiberaceae , Animales , Fertilidad/efectos de los fármacos , Genitales Masculinos/anatomía & histología , Genitales Masculinos/efectos de los fármacos , Genitales Masculinos/metabolismo , Masculino , Medicinas Tradicionales Africanas , Fitoterapia , Extractos Vegetales/administración & dosificación , Extractos Vegetales/química , Ratas , Ratas Wistar , Testículo/anatomía & histología , Testículo/efectos de los fármacos , Testículo/metabolismo , Testosterona/sangre , Testosterona/metabolismo , Zingiberaceae/químicaRESUMEN
UNLABELLED: Pterocarpus soyauxii Taub (Papilionaceae) is used in Cameroonian traditional medicine and pharmacopoeia to treat hypertension, diabetes, gastrointestinal parasitizes and cutaneous diseases. AIM OF THE STUDY: The present investigation was carried out to evaluate the safety of an aqueous stem bark extract of Pterocarpus soyauxii by determining toxicity after acute and sub-chronic oral administration in male and female rodents. MATERIALS AND METHODS: The acute toxicity test was conducted in mice. An aqueous extract of barks was administrated by gavage in single doses of 2.5-12.5 g/kg. General behaviour and mortality were examined for up to 7 days. The sub-chronic toxicity test was performed in rats. The plant extract was administered by daily gavage of 150-600 mg/kg for 42 days. Body weight, food and water intakes were followed weekly. Haematological, biochemical and organ parameters were determined at the end of the 42-day administration. RESULTS: In the acute study in mice, oral administration of the aqueous extract of Pterocarpus soyauxii caused dose-dependent general behaviour adverse effects and mortality. The no-observed adverse effect level (NOAEL) of the extract was 5.0 g/kg. The lowest-observed adverse effect level (LOAEL) was 7.5 mg/kg. Mortality increased with the dose, LD(50) was>10.75 g/kg for the mouse. In the sub-chronic study in rats, daily oral administration of the aqueous extract of Pterocarpus soyauxii did not result in death or significant changes in haematological or biochemical parameters, excepted increased hepatic catalase activity (P<0.05) at the dose of 600 mg/kg. No alteration was observed in body weight, food and water intake. Liver, kidney, lung and pancreas histopathology did not reveal morphological alteration. CONCLUSIONS: The results showed that the aqueous stem bark extract of Pterocarpus soyauxii Taub had very low toxicity in oral acute high dose administration and no toxicity in oral sub-chronic low dose administration and indicate that the plant could be considered safe for oral medication.
Asunto(s)
Pterocarpus/toxicidad , Administración Oral , Animales , Conducta Animal/efectos de los fármacos , Camerún , Etnofarmacología , Femenino , Dosificación Letal Mediana , Masculino , Medicinas Tradicionales Africanas , Ratones , Ratones Endogámicos BALB C , Nivel sin Efectos Adversos Observados , Corteza de la Planta/toxicidad , Extractos Vegetales/administración & dosificación , Extractos Vegetales/toxicidad , Plantas Medicinales/toxicidad , Ratas , Ratas WistarRESUMEN
Afrormosia laxiflora (A. laxiflora), Chenopodium ambrosioides (C. ambrosioides), Microglossa pyrifolia (M. pyrifolia) and Mimosa pudica (M. pudica) are plants used in traditional medicine in Cameroon to treat insomnia, epilepsy, anxiety, and agitation. They were evaluated for their anxiolytic like activity in mice. Animal models (elevated plus maze and stress-induced hyperthermia tests) were used. The four plants showed anxiolytic activity. In stress-induced hyperthermia test, A. laxiflora, C. ambrosioides, M. pyrifolia and M. pudica significantly antagonised the increase of temperature. ΔT° decreased from 0.75°C in the control group to 0.36°C at the dose of 110 mg/kg for A. laxiflora; from 1°C in the control group to -1.1°C at the dose of 120 mg/kg for C. ambrosioides; from 1.7°C in the control group to 0.2°C at the dose of 128 mg/kg for M. pyrifolia and from 1.3°C in the control group to 0.5°C at the dose of 180 mg/kg for M. pudica. In the elevated plus maze test, the four plants increased the number of entries into, percentage of entries into, and percentage of time in open arms. A. laxiflora, C. ambrosioides and M. pudica also reduced the percentage of entries and time in closed arms. In addition, C. ambrosioides, M. pyrifolia and M. pudica showed antipyretic activity by reducing the body temperature. The results suggested that C. ambrosioides, M. pyrifolia and M. pudica posses anxiolytic-like and antipyretic activities while A. laxiflora possesses only anxiolytic-like properties. These plants could be helpful in the treatment of anxiety and fever in traditional medicine in Cameroon.
Asunto(s)
Ansiolíticos/farmacología , Ansiedad/tratamiento farmacológico , Fitoterapia , Extractos Vegetales/farmacología , Plantas Medicinales/química , Análisis de Varianza , Animales , Ansiolíticos/aislamiento & purificación , Conducta Animal/efectos de los fármacos , Temperatura Corporal/efectos de los fármacos , Camerún , Chenopodium ambrosioides/química , Relación Dosis-Respuesta a Droga , Fiebre/tratamiento farmacológico , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Medicina Tradicional , Ratones , Mimosa/química , Actividad Motora/efectos de los fármacos , Extractos Vegetales/uso terapéutico , Pruebas Psicológicas , Estrés FisiológicoRESUMEN
Sclerocarya birrea is a medicinal plant used for the treatment of inflammatory- and bacterial-related diseases. The present study investigated in vitro and in vivo the effects of the stem bark methanol extract of S. birrea. Nitrite, TNF, IL-1beta, IL-6 and IL-12p40 production by bone marrow-derived macrophages (BMDM) pre-incubated with or without S. birrea, and stimulated with Lipopolysaccharide (LPS) or infected with live Mycobacterium bovis Bacillus Calmette Guérin (BCG) was evaluated. S. birrea extract inhibited, in a concentration-dependent manner, nitrite, TNF, IL-1beta, IL-6 and IL-12p40 production by BMDM stimulated with LPS or infected with live BCG. The iNOS expression was reduced by S. birrea after stimulation of BMDM with LPS. In addition, S. birrea inhibited the nuclear factor kB (NF-kB) activation by both LPS and BCG. The effects of the plant extract were also evaluated in an in vivo model of liver injury induced by D-galactosamine/LPS (D-GalN/LPS) administration in mice. S. birrea limited D-GalN/LPS-liver injury as assessed by a reduction in transaminases and TNF, IL-1beta, IL-6 serum levels, and translocation of NF-kB to the nucleus. Taken together, our data indicate that stem bark methanol extract of S. birrea possesses anti-inflammatory properties by inhibiting NF-kB activation and cytokine release induced by inflammatory or infectious stimuli.
Asunto(s)
Anacardiaceae , Antiinflamatorios/farmacología , Citocinas/antagonistas & inhibidores , Fallo Hepático/prevención & control , Extractos Vegetales/farmacología , Transporte Activo de Núcleo Celular/efectos de los fármacos , Animales , Citocinas/biosíntesis , Femenino , Galactosamina/toxicidad , Lipopolisacáridos/toxicidad , Fallo Hepático/inducido químicamente , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Masculino , Ratones , Ratones Endogámicos BALB C , Mycobacterium bovis/patogenicidad , FN-kappa B/antagonistas & inhibidores , Óxido Nítrico/biosíntesis , Óxido Nítrico Sintasa de Tipo II/antagonistas & inhibidoresRESUMEN
AIM OF THE STUDY: The stem bark of Mammea africana Sabine (Guttiferae) is used in African rain forest to treat various diseases, including diabetes mellitus. We investigated whether Mammea africana extract induced hypoglycaemic activity in rats. MATERIALS AND METHODS: We tested the effects of acute (5h) and sub-acute (21 days) oral administrations of the CH(2)Cl(2)-MeOH stem bark extract of Mammea africana (19-300 mg/kg body weight) on blood glucose levels of normal and streptozotocin (STZ)-induced type 1 diabetic rats. The effects were compared with those of glibenclamide. RESULTS: Acute administration reduced blood glucose in the diabetic rats only (33.87%, P<0.01). Sub-acute treatment for 21 days also reduced blood glucose level in diabetic rats (73.29%, P<0.01). A reduction or stabilization in total serum protein, triglyceride, cholesterol and alanine amino transferase levels was also observed. No effect was observed on body weight loss but food and water intakes were significantly reduced (P<0.01) in diabetic rats. The maximal anti-diabetic effect was obtained with the dose of 75 mg/kg and was more important than that of glibenclamide. CONCLUSION: It can be concluded that extracts of Mammea africana exhibited a significant anti-hyperglycaemic activity and improved the metabolic alterations in STZ-diabetic rats. These results provide a rationale for the use of Mammea africana to treat diabetes mellitus and hypercholesterolemia.
Asunto(s)
Diabetes Mellitus Experimental/tratamiento farmacológico , Hipoglucemiantes/uso terapéutico , Mammea , Extractos Vegetales/uso terapéutico , Animales , Diabetes Mellitus Experimental/sangre , Hipoglucemiantes/aislamiento & purificación , Hipoglucemiantes/farmacología , Masculino , Corteza de la Planta , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Tallos de la Planta , Ratas , Ratas WistarRESUMEN
Turraeanthus africanus (Meliacaeae) is known to possess a broad spectrum of pharmacological, medicinal and therapeutic properties. However, no extensive safety studies have been conducted on these extracts to date. The aim of this study was to evaluate toxicity of the aqueous extract of Turraeanthus africanus (Meliacaeae) after oral and intraperitoneal administration in mice. The acute toxicity was evaluated after single daily administration of the aqueous extract orally at doses of 0, 5, 10, 15, 20, 30 g kg(-1) or by the intraperitoneal route at doses of 0, 3, 6, 9, 12 g kg(-1) of raw material. The subacute toxicity was evaluated only by the intraperitoneal route for 6 weeks at doses of 1.5, 3, 6 g kg(-1) of raw material. Oral doses up to 30 g kg(-1) of the aqueous extract of Turraeanthus africanus (TA) did not produce mortality or significant changes in the general behaviour and gross appearance of internal organs of rats. However, the intraperitoneal administration of the aqueous extract of Turraeanthus africanus caused dose-dependent lethal effects. The acute intraperitoneal toxicity (LD(50)) of TA extract in mice was 7.2 g kg(-1). In subacute toxicity in mice, after the intraperitoneal administration of TA extract for 6 consecutive weeks, the feed consumption was significantly affected at the dose 3 g kg(-1) with P < 0.05 and at the dose 6 g kg(-1) with P < 0.001 and consequently had significant effect with P < 0.05 in body weight of animals. Level of triglyceride of treated animals lowered at dose 1.5 g kg(-1) with P < 0.001 and at dose 3 g kg(-1) and 6 g kg(-1) with P < 0.05. Total cholesterol level of treated animals lowered at dose 1.5 g kg(-1) with P < 0.005 and at dose 3 and 6 g kg(-1) with P < 0.001. HDL cholesterol level of treated animals lowered up to dose 6 g kg(-1) with P < 0.05 while levels of LDL cholesterol, serum and tissue creatinine of treated animals lowered at dose 3 g kg(-1) and dose 6 g kg(-1) with P < 0.05. Serum protein level of treated animal enhanced at dose 1.5 g kg(-1) and at dose 6 g kg(-1) with P < 0.05 while tissue creatinine level of treated animal enhanced with P < 0.001. The histology of liver, kidney and lung of the treated mice indicated morphological change of these organs (data not shown). No significant difference was observed during treatment concerning the haematological parameters. The results suggest that the plant is not toxic through the oral route in mice and that parenteral administration should be avoided.
Asunto(s)
Meliaceae/toxicidad , Corteza de la Planta/toxicidad , Administración Oral , Animales , Proteínas Sanguíneas/metabolismo , Peso Corporal/efectos de los fármacos , Colesterol/sangre , Creatinina/metabolismo , Relación Dosis-Respuesta a Droga , Ingestión de Alimentos/efectos de los fármacos , Femenino , Inyecciones Intraperitoneales , Masculino , Ratones , Preparaciones de Plantas/administración & dosificación , Plantas Medicinales/toxicidad , Pruebas de Toxicidad Aguda , Triglicéridos/sangreRESUMEN
ETHNOPHARMACOLOGICAL RELEVANCE: Solanum torvum fruits are commonly used in Cameroonian traditional medicine for treatment of arterial hypertension. It has been previously shown that intravenous administration of aqueous extract from dried fruits (AEST) reduced blood pressure. AIM: The present work evaluates acute toxicity and effects of oral administration of AEST in chronic arterial hypertension induced by L-NAME. Effects of AEST were also evaluated on isolated aorta. MATERIALS AND METHODS: AEST (200 mg/kg/day, p.o.) was given solely or concomitantly with L-NAME (40 mg/kg/day, p.o.) for 30 consecutive days. Animal body weight, systolic blood pressure and heart rate were measured before stating the treatment and at the end of each week. Urinary volume and urinary sodium and potassium contents were quantified before and at days 1, 15 and 30 of the treatment. Aorta from treated animals was tested for their sensitivity to noradrenaline and carbachol. Aorta from normal untreated rats was used to evaluate the in vitro vascular effect of AEST. RESULTS: The results showed that AEST did induce neither mortality nor visible signs of toxicity. When given solely or in co-administration with L-NAME, AEST significantly reduced animal's body weight. It amplified the hypertensive and cardiac hypertrophy effect of L-NAME and did not affect these parameters in normotensive animals. AEST increased the sensitivity to noradrenaline in normotensive and significantly reduced it in hypertensive animals. AEST significantly increased urinary volume and sodium excretion in L-NAME treated animals while reducing the sodium excretion in normotensive. In vitro, AEST induced a potent partial endothelium-dependent contraction of aortic ring; contractions that were partially antagonized by prazosin and verapamil and were not relaxed by carbachol. CONCLUSION: These results suggest that oral chronic administration of AEST induced potentiation of arterial hypertension and cardiac hypertrophy in L-NAME treated rats. These effects may result from a reduction in sensitivity to vasorelaxant agents and increase in hypersensitivity to contractile factors. AEST possess potent in vitro vasocontractile activity that may result from activation of both alpha(1)-adrenergic pathway and calcium influx.
Asunto(s)
Inhibidores Enzimáticos/farmacología , Frutas/química , Hipertensión/inducido químicamente , NG-Nitroarginina Metil Éster/farmacología , Solanum/química , Animales , Aorta Torácica/efectos de los fármacos , Presión Sanguínea/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Carbacol/farmacología , Femenino , Frecuencia Cardíaca/efectos de los fármacos , Hipertensión/fisiopatología , Técnicas In Vitro , Indicadores y Reactivos , Riñón/efectos de los fármacos , Masculino , Ratones , Relajación Muscular/efectos de los fármacos , Óxido Nítrico Sintasa/antagonistas & inhibidores , Norepinefrina/farmacología , Tamaño de los Órganos/efectos de los fármacos , Parasimpaticomiméticos/farmacología , Extractos Vegetales/farmacología , Extractos Vegetales/toxicidad , Ratas , Solanum/toxicidad , Vasoconstrictores/farmacologíaRESUMEN
Stem bark of Allanblackia monticola has been used in association with others plant in the Cameroonian folk medicine for the treatment of various diseases such amoebic dysentery, diarrhoea, lung infections, and skin diseases. The methylene chloride fraction, its isolated compounds like alpha-mangostin, lupeol and acid betulinic were screened for antioxidant activity using free radical scavenging method. These isolated compounds were further tested for anti-inflammatory properties using carrageenan-induced model. Methylene chloride fraction, showed concentration-dependent radical scavenging activity, by inhibiting 1,1-diphenyl-1-picryl-hydrazyl radical (DPPH) with an IC(50) value of 14.60 microg/ml. alpha-Mangostin and betulinic acid (500 microg/ml), showed weak radical scavenging activity with a maximum inhibition reaching 38.07 microg/ml and 26.38 microg/ml, respectively. Betulinic acid, lupeol and alpha-mangostin (5 mg/kg and 9.37 mg/kg) showed anti-inflammatory activity with a maximum inhibition of 57.89%, 57.14% and 38.70%, respectively. Methylene chloride fraction of Allanblackia monticola and some derivatives, have antioxidant and anti-inflammatory activities.
Asunto(s)
Antiinflamatorios/farmacología , Antioxidantes/farmacología , Clusiaceae/química , Extractos Vegetales/farmacología , Animales , Antiinflamatorios/administración & dosificación , Antiinflamatorios/aislamiento & purificación , Antioxidantes/administración & dosificación , Antioxidantes/aislamiento & purificación , Carragenina , Modelos Animales de Enfermedad , Femenino , Depuradores de Radicales Libres/aislamiento & purificación , Depuradores de Radicales Libres/farmacología , Inflamación/tratamiento farmacológico , Inflamación/fisiopatología , Concentración 50 Inhibidora , Masculino , Triterpenos Pentacíclicos , Corteza de la Planta , Ratas , Ratas Wistar , Triterpenos/administración & dosificación , Triterpenos/aislamiento & purificación , Triterpenos/farmacología , Xantonas/administración & dosificación , Xantonas/aislamiento & purificación , Xantonas/farmacología , Ácido BetulínicoRESUMEN
AIM OF THE STUDY: The methanol/methylene chloride (CH(3)OH/CH(2)Cl(2)) extract from the stem bark of Mammea africana was showed to possess vasodilating effect in the presence and the absence of N(omega)-nitro-l-arginine methyl ester (l-NAME). The present study was designed to evaluate the effects of the methanol/methylene chloride from the stem bark of Mammea africana. MATERIALS AND METHODS: The extract (200 mg/(kg day)) was administered orally in rats treated concurrently with l-NAME (40 mg/(kg day)). l-Arginine (100 mg/(kg day)) and captopril (20 mg/(kg day))were used as positive controls. Bodyweight, systolic arterial blood pressure and heart rate were measured weekly throughout the experiment period (28 days). At the end of treatment, animals were killed and the cardiac mass index evaluated. The aorta was used to evaluate the endothelium-dependant relaxation to carbachol. The aorta contraction induced by noradrenalin was also examined and expressed as a percentage of that induced by KCl. RESULTS: The extract neither affected the body weight nor the heart rate. The extract as captopril completely prevented the development of arterial hypertension. Both the substances failed to restore the endothelium-dependent vascular relaxation and increased the vascular contraction to norepinephrine in relation to KCl contraction. They also significantly reduced the left ventricular hypertrophy induced by l-NAME. CONCLUSION: These findings are in agreement with the traditional use of Mammea africana in the treatment of arterial hypertension and indicate that it may have a beneficial effect in patients with NO deficiency but will be unable to improve their endothelium-dependent vasorelaxation.
Asunto(s)
Inhibidores Enzimáticos , Hipertensión/tratamiento farmacológico , Mammea/química , NG-Nitroarginina Metil Éster , Fitoterapia , Animales , Presión Sanguínea/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Carbacol/farmacología , Frecuencia Cardíaca/efectos de los fármacos , Hipertensión/inducido químicamente , Hipertensión/fisiopatología , Masculino , Metanol , Cloruro de Metileno , Agonistas Muscarínicos/farmacología , Músculo Liso Vascular/efectos de los fármacos , Miocardio/patología , Tamaño de los Órganos/efectos de los fármacos , Corteza de la Planta/química , Extractos Vegetales/uso terapéutico , Tallos de la Planta/química , Ratas , Ratas Wistar , SolventesRESUMEN
Acanthus montanus is a plant used in Cameroon to treat pains and threatened abortion. The aim of this study was to evaluate the influence of methanol/methylene chlorides leaves extract from Acanthus montanus on Wistar pregnant rats and identify the substance(s) essential for these actions. Dams were treated orally from days 6 to 15 of the pregnancy at the dose levels of 0, 250, 500 and 1000 mg/(kgday). They were sacrificed on day 20 or allowed to deliver and wean. Various parameters were assessed. The F(1) generation offsprings were allowed to give birth to F(2) generation and a number of parameters assessed. The results showed that there was no maternal or organs toxicity. Embryotoxicity was observed during organogenesis manifested by reduction in foetal body weight, crown-rump and tail lengths and reduced ossification of extremities bones. However after delivery, these signs of growth retardation were seen before day 5, and henceforth, the treated pups regained all their parameters to normality. All others parameters for F(1) and F(2) generations were insignificant. beta-Sitosterol was the major chemical component of the extract and its role on these results could not be ignored. The MeOH/CH(2)Cl(2) extract of this plant is embryotoxic peri-natally at high doses but this failed to manifest after 5 days of post-natal survival. beta-Sitosterol may be central in the observed effects of the extract. This extract can be tolerated by pregnant patients.
Asunto(s)
Acanthaceae/química , Organogénesis , Extractos Vegetales/toxicidad , Hojas de la Planta/toxicidad , Teratógenos/toxicidad , Administración Oral , Animales , Femenino , Extractos Vegetales/química , Embarazo , Ratas , Ratas Wistar , Teratógenos/químicaRESUMEN
Cissus quadrangularis Linn grows in Savannah areas in Africa (Cameroon; Mali; Mauritania; Senegal; etc). In traditional medicine; the plant is used to treat anorexia; asthma; sickle cells; colds; pains; malaria; asthma and as an analgesic. In vivo animal models of epilepsy (maximal electroshock; n-methyl -d-aspartate; pentylenetetrazol; isonicotinic hydrazid acid and strychnine -induced convulsions or turning behavior) and insomnia (diazepam -induced sleep) were used. The aqueous extract of the stems of C. quadrangularis strongly increased the total sleep time induced by diazepam (50 mg/kg i.p.). It also protected mice against maximal electroshock; pentylenetetrazol; strychnine and n-methyl-d-aspartate-induced seizures or turning behavior and delayed the onset time of seizures induced by isonicotinic hydrazid acid. The results lead to the conclusion that the extract of C. quadrangularis possesses anticonvulsant and sedative properties in mice and could explain its use in traditional medicine in Africa; in the treatment of insomnia and epilepsy
Asunto(s)
África , Anticonvulsivantes , Cissus , Medicina Tradicional , Extractos Vegetales , ConvulsionesRESUMEN
Brillantaisia nitens Lindau (Acanthaceae) is traditionally used in Cameroon for the treatment of many diseases including cardiovascular disorders. We have studied its vasorelaxant effects in rat vascular smooth muscle. In this study, aqueous, methylene chloride, methanol, and methylene chloride/methanol leaves extracts of Brillantaisia nitens were tested for their relaxing ability in vitro. Strips of rat aorta, with or without intact endothelium, were mounted in tissue baths, contracted with KCl (60mM) or norepinephrine (10(-4)M), and then exposed to the plant extracts. These extracts exhibited concentration-dependent vasorelaxations of norepinephrine-induced contractions of intact aortic strips. The EC(50) were 0.42+/-0.01mg/ml (aqueous extract), 0.63+/-0.02mg/ml (methylene chloride extract), 0.73+/-0.02mg/ml (methanol extract) and 0.36+/-0.02mg/ml (methylene chloride/methanol extract). The methylene chloride/methanol (CH(2)Cl(2)/CH(3)OH) extract was the most potent relaxing extract. It caused a concentration-dependent and endothelium-independent relaxation of the rat aortic strips contracted by KCl or norepinephrine. On the NE-induced contraction, its maximal relaxant activity (109%) due to the dose of 1.5mg/ml, was not significantly modified by the pretreatment of aortic strips with indomethacin (89%, P>0.05) or with l-NAME (103%, P>0.05). This suggests that the vasorelaxation elicited by CH(2)Cl(2)/CH(3)OH extract was not mediated via endothelium-derived prostacyclin or nitric oxide. In contrast, this relaxation was markedly reduced by tetraethylammonium, a blocker of non-selective K(+) channels and glibenclamide, a blocker of ATP-sensitive K(+) channels. The CH(2)Cl(2)/CH(3)OH extract significantly inhibited Ca(2+)-induced concentration-contraction and the Ca(2+) influx in aortic strips incubated with 60mM KCl. These results indicate that the vasorelaxant effect of the CH(2)Cl(2)/CH(3)OH extract of Brillantaisia nitens is due to an inhibition of Ca(2+) influx, possibly via the activation of ATP-sensitive K(+) channels.
Asunto(s)
Acanthaceae , Músculo Liso Vascular/efectos de los fármacos , Vasodilatación/efectos de los fármacos , Vasodilatadores/farmacología , Adenosina Trifosfato/metabolismo , Animales , Aorta Torácica/efectos de los fármacos , Calcio/metabolismo , Camerún , Relación Dosis-Respuesta a Droga , Gliburida/farmacología , Técnicas In Vitro , Activación del Canal Iónico , Metanol/química , Cloruro de Metileno/química , Músculo Liso Vascular/metabolismo , Extractos Vegetales/farmacología , Hojas de la Planta , Bloqueadores de los Canales de Potasio/farmacología , Canales de Potasio/efectos de los fármacos , Canales de Potasio/metabolismo , Ratas , Ratas Wistar , Solventes/química , Tetraetilamonio/farmacología , Vasodilatadores/químicaRESUMEN
These studies focus on the toxicity leaf hexane extract of A. occidentale L (Anacardiaceae) used in Cameroon traditional medicine for the treatment of diabetes and hypertension. Previous findings on antidiabetic and anti-inflammatory have given support to the ethnopharmacological applications of the plant. After acute oral administration; it was found that doses of the extract less than 6 g/kg are not toxic. Signs of toxicity at high doses were asthenia; anorexia; diarrhoea; and syncope. The LD50 of the extract; determined in mice of both sexes after oral administration was 16 g/kg. In the subchronic study; mice received A. occidentale at doses of 6; 10 and 14 g/kg (by oral route) for 56 days. At doses of 2; 6 and 10 g/kg of extract; repeated oral administration to mice produced a reduction in food intake; weight gain; and behavioural effects. Liver or the kidney function tests were assessed by determining serum parameters like; creatinine; transaminases; and urea. All these parameters were significantly (p0.01) abnormal. Histopatological studies revealed evidence of microcopic lesions either in the liver or in the kidney which may be correlated with biochemical disturbances. We conclude that toxic effects of A. occidentale L hexane leaf extract occurred at higher doses than those used in Cameroon folk medicine
Asunto(s)
Anacardium/toxicidad , Diabetes Mellitus/terapia , Hexanos , Hipertensión/terapia , Extractos VegetalesRESUMEN
The aim of this work was to investigate the effect of daily oral administration of root bark methylene chloride/methanol extract of Ceiba pentandra (Linn) in streptozotocin-induced type-2 diabetic rats; and the effect of this treatment on the physiological and metabolic parameters that are related in diabetic animals. The diabetic rats were separated into four groups and each given the following samples by gavage; daily for 28 days: vehicle (diabetic control); Ceiba pentandra extract at the dose of 40 mg/kg; Ceiba pentandra extract at the dose of 75 mg/kg and glibenclamide (5 mg/kg). All the parameters were also determined in healthy (non diabetic) rats for comparison. The methylene chloride/methanol extract of Ceiba pentandra treatment significantly reduced the intake of both food and water as well as the levels of blood glucose; serum cholesterol; triglyceride; creatinine and urea; in comparison with diabetic controls. The treatment also improves impaired glucose tolerance but no effect was observed in the level of hepatic glycogen. The effect of Ceiba pentandra (40 mg/kg) was more prominent when compared to glibenclamide in lowering blood glucose; with the added benefit of considerably reducing serum cholesterol and triglyceride concentrations. The results of this experimental animal study indicated that Ceiba pentandra possesses antidiabetic activity; and thus is capable of ameliorating hyperglycaemia in streptozotocin-induced type-2 diabetic rats and is a potential source for isolation of new orally active agent(s) for anti-diabetic therapy
Asunto(s)
Ceiba , Diabetes Mellitus , Hipoglucemiantes , Ratas , EstreptozocinaRESUMEN
The aim of this work was to investigate the effect of daily oral administration of root bark methylene chloride/methanol extract of Ceiba pentandra (Linn) in streptozotocin-induced type-2 diabetic rats; and the effect of this treatment on the physiological and metabolic parameters that are related in diabetic animals. The diabetic rats were separated into four groups and each given the following samples by gavage; daily for 28 days: vehicle (diabetic control); Ceiba pentandra extract at the dose of 40 mg/kg; Ceiba pentandra extract at the dose of 75 mg/kg and glibenclamide (5 mg/kg). All the parameters were also determined in healthy (non diabetic) rats for comparison. The methylene chloride/methanol extract of Ceiba pentandra treatment significantly reduced the intake of both food and water as well as the levels of blood glucose; serum cholesterol; triglyceride; creatinine and urea; in comparison with diabetic controls. The treatment also improves impaired glucose tolerance but no effect was observed in the level of hepatic glycogen. The effect of Ceiba pentandra (40 mg/kg) was more prominent when compared to glibenclamide in lowering blood glucose; with the added benefit of considerably reducing serum cholesterol and triglyceride concentrations. The results of this experimental animal study indicated that Ceiba pentandra possesses antidiabetic activity; and thus is capable of ameliorating hyperglycaemia in streptozotocin-induced type-2 diabetic rats and is a potential source for isolation of new orally active agent(s) for anti-diabetic therapy
Asunto(s)
Ceiba , Complicaciones de la Diabetes , EstreptozocinaRESUMEN
Terminalia superba is highly regarded in some parts of Cameroon in traditional medical practice. We have studied the vasorelaxant effects of the stem bark methanol extract of T. superba on rat vascular smooth muscle. The results demonstrated that T. superba extract provoked a time-dependent relaxation of aortic rings precontracted with norepinephrine (10(-6) M). The vasorelaxant effect of the plant extract was not affected by endothelium removal or by pretreatment with indomethacin or N(W)-nitro-Larginine methyl ester (L-NAME). T. superba extract did not significantly, affect the contraction induced by 30 mM or 60 mM KCl as compared to those induced by NE. Relaxations elicited by T. superba extract were markedly reduced by glibenclamide, a putative blocker for K(ATP) channels and by tetraethylammonium, the non-specific K+ channel inhibitor. T. superba caused a time- and concentration-dependent relaxation of the rat aortic rings that were inhibited by charybdotoxin and iberotoxin but not by apamin. These finding indicate that T. superba extract at least partially relaxes the rat aorta by activating K+ channels, mainly KATP channels and large-conductance Ca2+ -activated K+ channels in rat aorta.
Asunto(s)
Aorta Torácica/efectos de los fármacos , Endotelio Vascular/efectos de los fármacos , Músculo Liso Vascular/efectos de los fármacos , Terminalia/química , Animales , Antiinflamatorios no Esteroideos/farmacología , Camerún , Caribdotoxina/farmacología , Inhibidores Enzimáticos/farmacología , Técnicas In Vitro , Indometacina/farmacología , Masculino , Metanol , Relajación Muscular/efectos de los fármacos , NG-Nitroarginina Metil Éster/farmacología , Óxido Nítrico Sintasa de Tipo III/antagonistas & inhibidores , Péptidos/farmacología , Corteza de la Planta/química , Extractos Vegetales/farmacología , Bloqueadores de los Canales de Potasio/farmacología , Cloruro de Potasio/farmacología , Ratas , Ratas Wistar , SolventesRESUMEN
The glucose-lowering efficacy of the aqueous stem bark extract of Trema orientalis (Ulmaceae) was evaluated both in normal and streptozotocin-induced diabetic rats. In normoglycemic rats, the single oral administration of the aqueous extract of T. orientalis failed to reduce blood glucose levels while in STZ-diabetic rats, the plant extract (38-300 mg/kg) exhibited significant hypoglycaemic activity with a maximum effect of 29.67%, 5 hours after administration of the 75 mg/kg dose when compared with the diabetic untreated group. Glibenclamide was not able to lower blood glucose in STZ-diabetic rats, while it significantly lowered the blood sugar in normoglycemic rats. The hypoglycaemic property of T. orientalis was also assessed by an oral glucose tolerance test (OGTT) in STZ-diabetic rats. The aqueous extract of T. orientalis and the reference drug, glibenclamide, (10 mg/kg) produced significant blood glucose lowering effects in the diabetic rats when compared to the diabetic controls. One week after repeated administration of T. orientalis extract, blood glucose levels were significantly decreased (p < 0.05) and still remained low after 2 weeks (p < 0.01). The results indicated that T. orientalis stem bark extract significantly reduces blood glucose in STZ-induced diabetic rats by a mechanism different from that of sulfonylurea agents. The present investigation provides pharmacological evidence that the use of this plant extract in traditional medicine for cardiovascular disease can be of benefit particulary in diabetic patients.
Asunto(s)
Diabetes Mellitus Experimental/tratamiento farmacológico , Hipoglucemiantes/farmacología , Trema/química , Animales , Glucemia/metabolismo , Peso Corporal/efectos de los fármacos , Diabetes Mellitus Experimental/sangre , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/inducido químicamente , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Ingestión de Líquidos/efectos de los fármacos , Ingestión de Alimentos/efectos de los fármacos , Prueba de Tolerancia a la Glucosa , Hipoglucemiantes/uso terapéutico , Masculino , Corteza de la Planta/química , Extractos Vegetales/farmacología , Ratas , Ratas WistarRESUMEN
Kalanchoe crenata Andr. (Crassulaceae) is a fleshy herbaceous plant used in the African traditional medicine as remedies against otitis, headache, inflammations, convulsions and general debility. In the present work, the analgesic effects of methylene chloride/methanol (1:1) (CH(2)Cl(2)/CH(3)OH) extract and its hexane, methylene chloride (CH(2)Cl(2)), ethyl acetate, n-butanol fractions and aqueous residue have been evaluated using acetic acid, formalin and pressure test. The anticonvulsant effects of the CH(2)Cl(2)/CH(3)OH extract were also investigated on seizures induced by pentylenetetrazol (PTZ 70 mg/kg), strychnine sulphate (STN 2.5 mg/kg) and thiosemicarbazide (TSC 50 mg/kg). CH(2)Cl(2)/CH(3)OH extract and its fractions, administered orally at the doses of 150 and 300 mg/kg, exhibited protective effect of at least 30% on the pain induced by acetic acid. The CH(2)Cl(2) fraction at 300 mg/kg showed a maximal effect of 78.49%. The CH(2)Cl(2)/CH(3)OH extract and its CH(2)Cl(2) fraction at the doses of 150 and 300 mg/kg significantly reduced the first phase of pain induced by formalin while the second phase was completely inhibited. The CH(2)Cl(2) fraction produced more than 45% reduction in the sensitivity to pain induced by pressure. The CH(2)Cl(2)/CH(3)OH extract of Kalanchoe crenata significantly increased the latency period in seizures induced by PTZ and significantly reduced the duration of seizures induced by the three convulsant agents. The extract protected 20% of animals against death in seizures induced by TSC and STN. These results suggest a peripheral and central analgesic activities as well as an anticonvulsant effect of the leaves of Kalanchoe crenata.
Asunto(s)
Analgésicos/uso terapéutico , Anticonvulsivantes/uso terapéutico , Kalanchoe , Fitoterapia , Extractos Vegetales/uso terapéutico , Convulsiones/tratamiento farmacológico , Animales , Convulsivantes/toxicidad , Femenino , Masculino , Ratones , Pentilenotetrazol/toxicidad , Hojas de la Planta/química , Ratas , Ratas Wistar , Convulsiones/inducido químicamente , Semicarbacidas/toxicidadRESUMEN
Stem bark extracts of Terminalia superba Engl. and Diels and Canarium schweinfurthii Engl. are used in Africa for the treatment of various ailments, including diabetes mellitus. The anti-diabetic effects of the methanol/methylene chloride extracts of the stem barks on streptozotocin (STZ)-induced diabetes were evaluated on male rats. Through the subcutaneous route, diabetes was induced using 60 mg/mL of streptozotocin. After 2 days, the rats received, by gavage, 150 mg/kg and 300 mg/kg of extract daily for 14 days. At 300 mg/kg, the two extracts (Terminalia superba and Canarium schweinfurthii), significantly showed at least 67.1% and 69.9% reduction in blood glucose level, respectively, while insulin (three units) given subcutaneously and once daily, had 76.8% reduction compared to diabetic untreated control rats. Similarly, the weight gains were 6.6% and 4.9%, respectively, and were comparable to the normal rats, whereas, diabetic untreated rats lost 14.1% body weight. Still with the same dose, there was 68.5% and 58.5% (p < 0.001) significant decrease in food consumption and 79.7% and 64.0% (p < 0.001) in fluid intake by diabetic rats treated with the respective plant extracts. The insulin-treated rats showed 56.4% and 75.8% decrease in food and fluid intake compared to an augmentation for diabetic control rats, 43.0% and 383.8%, respectively, at the end of the second week of experimentation. These results showed that the plant extracts can reverse hyperglycemia, polyphagia and polydipsia provoked by streptozotocin, and thus, they have anti-diabetic properties.