Anticonvulsant effects of ethanol stem bark extract of Lannea barteri (Anacardiaceae) in mice and chicks.

ETHNOPHARMACOLOGICAL RELEVANCE: Preparation of Lannea barteri is used in the treatment of epilepsy, gastritis, childhood convulsions among other uses in northern Nigeria for many years. The popularity of its efficacy is well established among the Traditional Medical Practitioners. AIM OF THE STUDY: The present study aimed at screening the ethanol stem bark extract of Lannea barteri for possible anticonvulsant action. MATERIALS AND METHOD: Anticonvulsant screening was carried out using pentylenetetrazole (PTZ), strychnine (STN) and picrotoxin (PTC) induced seizures in mice while Maximal electroshock (MES) test was carried out in day old chicks. Preliminary phytochemical screening of the extract was performed on the extract. The intraperitoneal median lethal dose (LD50) was carried out in mice. RESULTS: The intraperitoneal (i.p.) LD50 of the extract was estimated to be 567.70 mg/kg in mice. Lannea barteri (160 mg/kg) significantly (p ≤ 0.05) delayed the mean onset of seizures induced by PTZ when compared with normal saline treated group. Similarly, the extract at 160 mg/kg significantly (p ≤ 0.05) prolonged the latency of convulsion induced by STN. Lannea barteri (40 mg/kg) significantly (p ≤ 0.05) delayed the mean onset of seizures induced by picrotoxin in mice. The extracts at all the doses tested showed no observable effect in decreasing the mean recovery time of convulsed chicks in MEST. Flavonoids, alkaloids, tannins, saponins and glycosides were found present in the stem bark extract. CONCLUSION: Our findings revealed that the ethanol stem bark extract of Lannea barteri contained bioactive constituents that may be useful in the management of petit mal epilepsy and supports the ethnomedical claim for the use of its stem bark in the management of epilepsy.

Anticonvulsant activity of aqueous fraction of Carissa edulis root bark.

CONTEXT: Carissa edulis Vahl (Apocynaceae) is used in Nigerian folk medicine to manage a plethora of diseases including epilepsy, cancer, and inflammation; its efficacy is widely acclaimed among communities of northern Nigeria. OBJECTIVE: This study establishes anticonvulsant activities of aqueous fraction of ethanol root bark extract of Carissa edulis (RAF) and sub-fractions (S1 and S2) in animal models. MATERIALS AND METHODS: We evaluated the acute toxicity of the RAF, S1 and S2, and the anticonvulsant activity using pentylenetetrazole (PTZ), picrotoxin, strychnine, N-methyl-d-aspartate (NMDA), isoniazid (INH), and aminophylline-induced seizures in mice. Their effects on maximal electroshock (MES) and kindling-induced seizures were studied in chicks and in rats, respectively, and in the electrophysiological study. The doses used for RAF were 150, 300, and 600 mg/kg while S1 and S2 were 250, 500, and 1000 mg/kg. Both RAF and sub-fractions were administered once during the experiment. RESULTS: The intraperitoneal LD50 of the RAF was estimated to be 2222.61 mg/kg and that of the S1 and S2 were above 5000 mg/kg. RAF protected the mice by 50% while sub-fractions by 16.67% against PTZ-induced seizures. RAF offered 33.33 and 16.67% protection against strychnine and NMDA models, respectively. However, RAF offered 66.67-33.33% protections against aminophylline-induced seizures at doses of 150 and 600 mg/kg, but RAF, S1, and S2 had no effect on MES-induced seizures. DISCUSSION AND CONCLUSION: Our results validate the use of the plant traditionally in the management of epilepsy, thus supporting the appraisal of biologically active components of this plant as antiepileptic agents.

Psychopharmacological potentials of methanol leaf extract of Securinega virosa Roxb (Ex Willd) Baill. in mice.

Schizophrenia is a highly disabling chronic psychiatric illness. The existing antipsychotic agents are associated with untoward effects and drug interactions leading to the intensification of search for newer agents with better efficacy and safety profile. Securinega virosa is a commonly used medicinal plant in African traditional medicine. The decoction of the leaves of the plant in combination with other plants is used in the management of mental illness. In this study, we evaluate the antipsychotic potential of the methanol leaf extract (25, 50 and 100 mg kg(-1)) of the plant using apomorphine-induced stereotypic climbing behavior and swim-induced grooming tests, all in mice. The CNS depressant effect was also evaluated using ketamine-induced sleep test mice. The extract at the highest dose tested (100 mg kg(-1)) significantly reduced the apomorphine (1 mg kg(-1))-induced stereotypic climbing behavior after 30 min. Similarly, haloperidol (2 mg kg(-1)), the standard agent significantly (p<0.001) decreased the mean climbing behavior. In the swim-induced grooming test, the extract significantly (p<0.01) and dose-dependently decreased the total grooming time. Similarly, haloperidol (2 mg kg(-1)) significantly (p<0.001) decreased the mean grooming activity. The extract significantly increased the total ketamine-induced sleep duration at doses of 50 and 100 mg kg(-1). These findings suggest that the extract possesses antipsychotic and sedative potentials and lend credence to the ethnomedical use of the leaves of the plant in the management of mental illness.

Safety assessment of the standardized extract of Carissa edulis root bark in rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Preparations of Carissa edulis (Vahl) have been used in the Nigerian traditional medicine for the management of fever, sickle cell disease, epilepsy, pain and inflammation for many years and their efficacy is widely acclaimed among the Hausa communities of northern Nigeria. AIM OF THE STUDY: The present studies aimed at evaluating the toxicological properties of the standardized ethanol extract of C. edulis root bark in rats, in order to determine its safety and to complement earlier efficacy studies on this widely used medicinal plant. MATERIALS AND METHODS: High performance liquid chromatography (HPLC) and preliminary phytochemical analysis of the extract were conducted and its oral median lethal dose (LD50) determined. Signs of toxicity, body weight changes, relative organs weight, feed and water consumption were monitored following 28 days of daily oral administration of graded doses of the extract in rats. Effects of the extract on sex hormones, low- and high-density lipids, hematological and biochemical parameters were examined and pathological changes of the vital organs after treatment with the extract were also investigated. RESULTS: The oral LD50 of the extract was estimated to be >5000 mg/kg. The body weights of treated rats increased progressively, but the changes were not significantly different from the control groups. The extract neither produces significant changes in feed and water consumption nor affected the relative organs weight. Although some variations were observed in hormonal and lipid profiles hematological and biochemical indices, these important parameters were normal and within acceptable limits. No lesions or pathological changes of the organs attributable to treatment with the extract were observed from the pathological examinations. The HPLC fingerprint of the extract shows a spectrum profile characteristic of C. edulis, while the preliminary phytochemical screening revealed the presence of saponins, flavonoids, tannins, anthraquinones and cardiac glycosides. CONCLUSION: Our results provided evidence that short-term administration of the standardized ethanol extract of C. edulis root bark at doses lower than 1000 mg/kg is safe in rats and may not exert severe toxic effects.

Behavioral properties of Balanites aegyptiaca in rodents.

ETHNOPHARMACOLOGICAL RELEVANCE: Balanites aegyptiaca is a native plant from the dry tropical areas of Africa and Arabia. It has been used in traditional medicine to treat psychoses, epilepsy, rheumatism and for the management of cough, liver and spleen conditions for many years. The plant is also used as antihelmintic and molluscicide. AIM OF THE STUDY: The present studies aimed at investigating the behavioral properties of ethanol extract of the root of this medicinal plant, which is already in common applications in the Nigerian traditional medicine. MATERIALS AND METHODS: The intraperitoneal and oral mean lethal dose (LD(50)) of the extract was determined using the Lorke's method. The preliminary phytochemical screening of the extract was carried out to identify the secondary metabolites in the extract. Furthermore, the behavioral properties of the extract were evaluated using diazepam-induced sleep, open field test, staircase test and beam walking assay all in mice. RESULTS: The extract significantly (p<0.001) prolonged the duration diazepam (20mg/kg i.p)-induced sleep in mice dose dependently. However, the extract showed no significant effect on the onset of diazepam-induced sleep. In the open field test, the extract (150 and 300 mg/kg) and diazepam (0.05 mg/kg) produced a significant (p<0.05, p<0.005 and p<0.001) decrease in the number of square crossings. There was no significant effect on the number of centre square crossing following the administration of the extract. The extract (75 and 150 mg/kg) and diazepam (0.05 mg/kg) produced a significant (p<0.05) decrease in the number of rearing suggestive of sedation. In the staircase experiment there was a decrease in the number of upward step climbing as well as number of rearing suggesting anxiolytic and sedative properties of the extract. In the beam walking assay the extract did not produce any significant increase in the time taken to complete task as compared to diazepam 1mg/kg which was significant at p<0.05. Furthermore, 30 mg/kg of the extract and diazepam 1mg/kg showed significant (p<0.05) mean number of foot slips, suggesting that the central nervous system depressant activity might not necessarily due to peripheral neuromuscular blockade. CONCLUSION: The result indicates that the extract of Balanites aegyptiaca possess biologically active compound(s) that have anxiolytic and sedative properties, which support the ethnomedicinal use of the plant as antipsychotic and antiepileptic agents.

Evaluation of analgesic and anti-inflammatory effects of ethanol extract of Ficus iteophylla leaves in rodents.

This study was undertaken to investigate the leaf part of the plant for analgesic and anti-inflammatory. The ethanol extract of Ficus iteophylla leaves (100, 200, and 400 mg kg(-1), i.p) was evaluated for analgesic and anti-inflammatory activities. The analgesic effect was studied using acetic acid-induced abdominal constriction and hot plate test in mice, while the anti-inflammatory effect was investigated using carrageenan induced paw oedema in rats. The ethanol extract at 100 mg kg(-1), 200 mg kg(-1), and 400 mg kg(-1) significantly (P< 0.05) inhibited acetic acid induced writhes by 1.50 ± 0.43, 3.0 ± 0.82 and 1.0 ± 0.82 respectively. It also exhibited significantly (P< 0.05) anti-inflammatory by 0.11 ± 0.02, 0.11 ± 0.03, 0.08 ± 0.01 respectively. The preliminary phytochemical screening of the plant extract revealed the presence of flavonoids, steroids, tannins and saponins while the effect of flavonoids, steroids and tannins on analgesic and inflammatory has been reported. The intraperitoneal median lethal dose (LD(50)) value of the extract was found to be 3807.8 mgkg(-1) body weights. The result obtained from this study shows that the extract of Ficus iteophylla contained phytochemical constituents with analgesic and anti-inflammatory activities, therefore the leaf part of the plant could be used in the management of pain and inflammatory conditions.

Anticonvulsant activity of Carissa edulis (Vahl) (Apocynaceae) root bark extract.

AIM OF THE STUDY: To investigate the anticonvulsant activity of root bark extract of Carissa edulis. MATERIALS AND METHODS: The median lethal dose (LD(50)) of Carissa edulis extract was determined using Lork's method (1983). The anticonvulsant activity of the extract was assessed in pentylenetetrazole (PTZ)-induced convulsion in mice and maximal electroshock test (MEST) in chicks, with benzodiazepine and phenytoin as standard drugs, respectively. While mechanistic studies were conducted using both flumazenil, a GABA(A)-benzodiazepine receptor complex site antagonist and naloxone a non-specific opioid receptor antagonist. RESULTS: The median lethal dose (LD(50)) of Carissa edulis was 282.8mg/kg and over 5000mg/kg following intraperitoneal and oral administration, respectively. Carissa edulis produced 40% and 20% protection against convulsion at 5 and 20mg/kg, respectively, compared with 100% protection with benzodiazepine. The mean onset and percentage protection against convulsion in Carissa edulis extract-treated mice were reduced by flumazenil and naloxone. Carissa edulis exhibited dose-dependent inhibition of the convulsion induced by MEST with 20mg/kg providing 90% protection while phenytoin (20mg/kg) produced 100% protection. CONCLUSION: These results suggest that Carissa edulis possesses biologically active constituent(s) that have anticonvulsant activity which supports the ethnomedicinal claims of the use of the plant in the management of epilepsy.

Behavioural effects of the methanolic root bark extract of Securinega virosa in rodents.

Securinega virosa is used traditionally as sedative in children and in mental illnesses. In this study, the behavioral effects of methanolic root bark extract of S. virosa were investigated in mice. The results revealed that the extract significantly (P<0.05) and dose-dependently reduced the onset and prolonged the duration of sleep. The extract significantly (P<0.05) decreased exploratory activity and reduced the rate of apomorphine-induced stereotyped climbing at the doses tested (6.25-25 mg/kg). It also produced a significant and dose-dependent motor coordination deficit in mice at the doses tested (P<0.01). The intraperitoneal median lethal dose in mice was 774.6 mg/kg while the preliminary phytochemical screening revealed the presence of alkaloids, tannins, saponins and flavonoids. These results suggest that methanolic root bark extract of S. virosa contains biologically active principles that are sedative in nature and lend pharmacological credence to the ethnomedical use of the plant.

PRELIMINARY GASTROINTESTINAL STUDIES OF METHANOL EXTRACT OF INDIGOFERA PULCHRA WILLD IN RODENTS.

In this study, the effect of the methanol extract of Indigofera pulchra Willd. (Papillionaceae) was investigated against castor oil induced diarrheoa. Its effects on perfused isolated rabbit jejunum and guinea pig ileum were also evaluated. The extract produced a dose-dependent protection against the castor oil-induced diarrheoa in mice with the highest protection (100%), obtained at 200 mgkg-1 comparable to that of loperamide (5 mgkg-1), a standard antidiarrhoeal drug. The extract (0.4 - 6.4 mgml-1) produced a concentration relaxation of the rabbit jejunum. However, no observable effect was noticed when the guinea pig ileum was treated. The extract blocked the contractile effect of acetylcholine (2 × 10-8 gml-1) and histamine (4 × 10-7 gml-1) on both rabbit jejunum and guinea pig ileum. Phytochemical screening revealed the presence of flavonoids, tannins, saponins and steroids. The intraperitoneal median lethal dose (LD50) value for the extract was found to be 2154.0 mgkg-1. The results obtained revealed that the extract possesses pharmacologically active compounds with gastrointestinal relaxant and antidiarrhoeal activities and may possibly explain the use of the plant in traditional medicine for the treatment of gastrointestinal disorder.

Psychopharmacological Properties of the Saponin Fraction of Ficus Platyphylla Stem Bark

The psychopharmacological effects of a saponin-rich fraction (SFG) obtained from crude methanolic extract of Ficus platyphylla stem bark were studied on spontaneous motor activity (SMA); pentobarbitalinduced sleep; motor coordination; amphetamine-induced hyperactivity and stereotyped behaviour; catalepsy; forced swim and tail suspension tests in rodents. SFG reduced SMA dose dependently; suggesting that it may contain psychoactive principles with sedative effects. The fraction shortened the onset and prolonged the duration of pentobarbital-induced sleep; which confirmed its sedative properties. The fraction diminished immobility time in forced swim and tail suspension tests; which is indicative of antidepressant properties. It attenuated amphetamine-induced hyperactivity and stereotyped behaviour; induced catalepsy and exacerbated haloperidol-induced catalepsy in rodents; but had no effect on motor coordination in the treadmill experiment at the doses tested. These effects were similar to those of classical neuroleptics and antidepressants. Our study provides scientific evidence of psychopharmacological effects of the saponin fraction of Ficus platyphylla stem bark and therefore supports further development of its psychoactive components as antipsychotics and antidepressants

Anti-diarrheal activity of the leaf extracts of Daniellia oliveri Hutch and Dalz (Fabaceae) and Ficus sycomorus Miq (Moraceae).

The leaves of the plants Daniellia oliveri (Fabaceae) and Ficus sycomorus (Moraceae) used in diarrhea treatment in Hausa ethnomedicine of Northern Nigeria were investigated. The study was carried out on perfused isolated rabbit jejunum and castor oil-induced diarrhea in mice. The n-butanol extracts: NBD and NBF (0.16-3.2 mg/ml) caused a dose-dependent relaxation of isolated rabbit jejunum. The acute toxicity test for NBD and NBT in mice established an i.p LD(50) of > 4000 mg/kg for D. oliveri and 1131.4 mg/kg for F. sycomorus. In castor oil-induced diarrhea, 80% protection was observed for D. oliveri at doses of 200 mg/kg and 60% protection was observed at 100 mg/kg and 50 mg/kg respectively. For F. sycomorus 100% protection was observed at doses of 120 mg/kg and 60 mg/kg, for the n-butanol extract. The antidiarrheal activity was comparable to loperamide 5 mg/kg. The result revealed that the extracts have pharmacological activity against diarrhea.

Phytochemical, analgesic and anti-inflammatory effects of the ethylacetate extract of the leaves of Pseudocedrella kotschyii.

Phytochemical screening was carried out on the ethylacetate portion of the ethanolic extract of the leaves of Pseudocedrella kotschyii and then evaluated for its analgesic (acetic acid-induced writhing) and anti-inflammatory (raw egg albumin-induced oedema) activities in mice and rats respectively. Phytochemical screening of the ethylacetate partition portion of ethanolic extract revealed the presence of flavonoids, glycosides and tannins as major chemical constituents. Alkaloids saponins, cardiac glycosides, steroids were not dictated in the extract. The ethylacetate extract (50 and 100 mg/kg i.p) exhibited significant activity (p<0.05) against acetic acid-induced writhing in a dose dependent manner. In the anti-inflammatory activity the ethylacetate extract (50 and 100 mg/kg i.p.) caused a slight effect against the raw egg albumin-induced oedema. The effect was however observed not to be dose dependent. All these effects were compared with standard drug piroxicam (20 mg/kg i.p.).

Phytochemical; Analgesic and Anti-Inflammatory Effects of the Ethylacetate Extract of the Leaves of Pseudocedrella Kotschyii

Phytochemical screening was carried out on the ethylacetate portion of the ethanolic extract of the leaves of Pseudocedrella kotschyii and then evaluated for its analgesic (acetic acid-induced writhing) and anti-inflammatory (raw egg albumin-induced oedema) activities in mice and rats respectively. Phytochemical screening of the ethylacetate partition portion of ethanolic extract revealed the presence of flavonoids; glycosides and tannins as major chemical constituents. Alkaloids saponins; cardiac glycosides; steroids were not dictated in the extract. The ethylacetate extract (50 and 100 mg/kg i.p) exhibited significant activity (p0.05) against acetic acid-induced writhing in a dose dependent manner. In the anti-inflammatory activity the ethylacetate extract (50 and 100 mg/kg i.p.) caused a slight effect against the raw egg albumin-induced oedema. The effect was however observed not to be dose dependent. All these effects were compared with standard drug piroxicam (20 mg/kg i.p.)