Abdullahi H. Yaro

Behavioral properties of Balanites aegyptiaca in rodents.

ETHNOPHARMACOLOGICAL RELEVANCEnBalanites 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.nnnAIM OF THE STUDYnThe 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.nnnMATERIALS AND METHODSnThe intraperitoneal and oral mean lethal dose (LD(50)) of the extract was determined using the Lorkes 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.nnnRESULTSnThe 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.nnnCONCLUSIONnThe 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.

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

ETHNOPHARMACOLOGICAL RELEVANCEnPreparations 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.nnnAIM OF THE STUDYnThe 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.nnnMATERIALS AND METHODSnHigh 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.nnnRESULTSnThe 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.nnnCONCLUSIONnOur 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.

Analgesic and anti-inflammatory effects of the methanol stem bark extract of Prosopis africana

Prosopis africana (Guill. & Perr.) Taub. (Mimosoideae) is a shrub used for menstrual and general body pain in Nupe land in north central Nigeria. In this study, the methanol extract of the stem bark of Prosopis africana (at doses of 62.5, 125, and 250u2009mg/kg) was evaluated for analgesic and anti-inflammatory activities using acetic acid-induced writhing assay and carrageenan-induced inflammation in rats. The extract significantly (P <0.05) attenuated the acetic acid-induced writhing with the highest activity observed at the highest dose, 250u2009mg/kg (76.89%) comparable to that of piroxicam (83.16%) the standard agent used. In the carrageenan-induced inflammation assay, the extract showed significant anti-inflammatory activity (P <0.001) from the third hour. The preliminary phytochemical screening revealed the presence of flavonoids, saponins, carbohydrates, cardiac glycosides, tannins, and alkaloids. The oral median lethal dose was found to be 3807.9u2009mg/kg in mice and > 5000u2009mg/kg in rats. This study supports the folkloric claim of the use of Prosopis africana in the management of pain.

Central depressant activity of butanol fraction of Securinega virosa root bark in mice

ETHNOPHARMACOLOGICAL RELEVANCEnSecurinega virosa is a commonly used medicinal plant in African traditional medicine in the management of epilepsy and mental illness. Previous studies in our laboratory showed that the crude methanol root bark extract of the plant possesses significant behavioral effect in laboratory animals. In an attempt to isolate and characterize the biological principles responsible for the observed activity, this study is aimed at evaluating the central depressant activity of the butanol fraction of the methanol root bark extract of Securinega virosa.nnnMATERIALS AND METHODSnThe medial lethal dose of the butanol fraction was estimated using the method of Lorke. Preliminary phytochemical screening was conducted on the butanol fraction using standard protocol. The behavioral effect of the butanol fraction (75, 150 and 300mg/kg) was evaluated using diazepam induced sleep test, hole-board test, beam walking assay, staircase test, open field test and elevated plus maze assay, all in mice.nnnRESULTSnThe median lethal dose of the butanol fraction was estimated to be 1256.9mg/kg. The preliminary phytochemical screening revealed the presence of tannins, saponins, alkaloids, flavonoids, cardiac glycosides, similar to those found in the crude methanol extract. The butanol fraction significantly (P<0.001) reduced the mean onset of sleep in mice and doubled the mean duration of sleep in mice at the dose of 75mg/kg. The butanol fraction and diazepam (0.5mg/kg) significantly (P<0.01-0.001) reduced the number of head dips in the hole-board test suggesting sedative effect. The sedative effect of the butanol fraction was further corroborated by its significant (P<0.01-0.001) reduction of the number of step climbed and rearing in the staircase test. The butanol fraction did not significantly increase the time taken to complete the task and number of foot slips in the beam walking assay, suggesting that it does not induce significant motor coordination deficit. Diazepam (2mg/kg), the standard agent used significantly (P<0.01) increased the number of foot slips. In the open field test, the butanol fraction significantly reduced the number of square crossed as well as the number of rearing. However, the butanol fraction did not significantly alter the behavior of mice in the elevated plus maze assay, while diazepam (0.5mg/kg) significantly (P<0.05) increased the time spent in the open arm and reduced the number of closed arm entry.nnnCONCLUSIONnThe findings of this study suggest that the butanol fraction of Securinega virosa root bark contains some bioactive principles that are sedative in nature.

Aqueous Methanol Extracts of Cochlospermum tinctorium (A. Rich) Possess Analgesic and Anti-inflammatory Activities.

Cochlopermum tinctorium A. Rich. (Cochlospermaceae) is a commonly used medicinal plant in the West Africa sub-region for the management of various conditions including pain and inflammatory conditions. In the present study, we report the analgesic and anti-inflammatory activities of the aqueous methanol leaf (20-80 mg/kg), root (7.5-30 mg/kg), and root bark (20-80 mg/kg) extracts of the plant. The analgesic potentials of the extracts were studied using acetic acid induced writhing and hot plate tests in mice while the anti-inflammatory activity was investigated using carrageenan-induced paw edema in rats.The extracts significantly and dose dependently inhibited the acetic acid-induced writhing in mice. However, the highest protection against writhing was produced by aqueous methanol leaf extract at the dose of 80 mg/kg (96.65%) which even was greater than that of the standard agent, ketoprofen (82.30%). The extracts did not significantly increase mean latency of response in the hot plate test. However, aqueous methanol root bark extract at the dose of 20 mg/kg significantly (P < 0.05) increased the mean latency of pain response. While the extracts of the root and root bark extracts of the plant afforded non dose-dependent protection against carrageenan-induced edema, the aqueous methanol leaf extract significantly and dose-dependently inhibited carrageenan-induced hind paw edema at the end of the third hour.The present study suggests that the aqueous methanol leaf, root, and root bark extracts of Cochlopermum tinctorium possess analgesic and anti-inflammatory activities which lend some credence to the ethnomedical claim of the use of the plant in the management of pain and inflammatory conditions.

Anticonvulsant activity of butanol fraction of methanol root bark extract of Securinega virosa Roxb (ex Willd) Baill. in laboratory animals

Securinega virosa is a commonly used medicinal plant in African traditional medicine in the management of epilepsy. In an attempt to isolate and characterize the bioactive principles responsible for the anticonvulsant property, the crude methanol root bark extract of the plant was exhaustively partitioned into petroleum ether, chloroform, ethyl acetate and n-butanol. The anticonvulsant potential of the n-butanol fraction (75, 150 and 300 mg/kg) was evaluated using maximal electroshock (MES) test in chicks, strychnine, picrotoxin, 4-aminopyridine and pentylenetetrazole-induced seizures in mice. The fraction did not protect the chicks against tonic-hind limb extension due to MES. Similarly, the fraction did not afford significant protection against seizures induced by strychnine, aminopyridine and picrotoxin contrary to the observations of protections in the crude extract, against pentylenetetrazole-induced seizure, the fraction afforded 66.67% protection and significantly (P<0.01) delayed the onset of seizure in unprotected animals. Column chromatographic separation of the n-butanol fraction yielded three major sub-fractions which were subjected to anticonvulsant screening using pentylenetetrazol (PTZ)-induced seizure. The anticonvulsant potential of the n-butanol fraction was retained in the more polar sub-fractions. The findings of this study suggest that the n-butanol fraction Securinega virosa root bark contains bioactive principle(s) that possess anticonvulsant activities which may be beneficial against absence seizure. This lends further credence to the ethnomedicinal claim of the use of the root of S. virosa in the management of epilepsy. n n xa0 n n Key words: Securinega virosa, epilepsy, seizure, maximal electroshock, pentyleneterazole, picrotoxin, 4-aminopyridine, strychnine.

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

ETHNOPHARMACOLOGICAL RELEVANCEnPreparation 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.nnnAIM OF THE STUDYnThe present study aimed at screening the ethanol stem bark extract of Lannea barteri for possible anticonvulsant action.nnnMATERIALS AND METHODnAnticonvulsant 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.nnnRESULTSnThe 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.nnnCONCLUSIONnOur 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.

Analgesic and anti-inflammatory studies on crude ethanol extract of Cadaba farinosa Forssk leaf in mice and rats

The plant Cadaba farinosa Forssk. is used in the treatment of pains, dysentery, rheumatism, cough, and fever. Phytoconstituents include alkaloids, anthraquinones, cardiac glycosides, flavonoids, saponins and tannins. The intraperitoneal LD 50 of the crude ethanol leaf extract (CEE) was found to be 2154.1 mg/kg body weight in mice. The analgesic activity was investigated using acetic acid-induced writhing and hot plate tests in mice while Antiinflammation potential was investigated using carrageenan-induced hind paw oedema in rats. The extract at all the doses tested and piroxicam produced significant decrease in number of writhes at p ≤ 0.05 for extract and piroxicam compared to normal saline group. There was a significant increase (p≤ 0.01) in the pain-reaction time for thermally induced pain at 30 min of both 300 mg/kg CEE and 20 mg/kg pentazocine (standard drug). At 60 min, the significant increase (p≤ 0.05) was at 75 mg/kg CEE and 20 mg/kg pentazocine when compared to the control. The highest significant increase in mean pain reaction time for 75, 150 mg/kg CEE and pentazocine was observed at 90 min compared to the normal saline group. There was no significant difference in the mean pain latency time for thermally-induced pain between CEE and pentazocine for doses tested at 30, 60 and 120 min except for pentazocine with significant increase of p≤ 0.05 compared to the control group. There was generally a significant reduction (p ≤ 0.01) in mean paw diameter for both the extract and piroxicam treated groups compared to control group throughout the study. Keywords: Analgesic activity, Cadaba farinosa , acetic acid, carrageenan, pain, writhes, hot plate, paw oedema

Antipsychotic and sedative effects of residual aqueous fraction of ethanol root bark extract of Carissa edulis (Vahl) in mice

Carissa edulis (Vahl) (Family Apocynaceae) is used traditionally for the treatment of headache, gonorrhea, syphilis, rheumatism, epilepsy and mental disorders. This study investigated the antipsychotic and sedative effects of the residual aqueous fraction of ethanolic root bark extract of Carissa edulis using mice models: apomorphine-induced stereotypic climbing behaviour, amphetamine-induced hyperlocomotion in open field, walking beam assay for motor coordination deficit, hole board test for exploratory behavior and diazepam-induced sleep. The residual aqueous fraction (RAF) at 150, 300 and 600 mg/kg, produced significant dose dependent decrease (p<0.05) in stereotypic climbing behaviour induced by apomorphine; while at doses of 300 and 600 mg/kg, it produced a significant (p<0.05) reduction in locomotor activity induced by amphetamine. In addition, it exhibited (150, 300 and 600 mg/kg) significant dose dependent increase (p<0.05) in the time taken to cross the beam. Similarly, at doses of 300 and 600 mg/kg significantly (p<0.05) potentiated the duration of sleep, but there was no significant difference in the number of head dips in the hole board experiment. Therefore, the results of this study suggest that the residual aqueous fraction of Carissa edulis contains bioactive principles with antipsychotic and sedative property. Thus, justify the traditional use of the plant in mental illness. Keywords: Carissa edulis ; Antipsychotic; Sedative; Apomorphine; Amphetamine

Dichloro-substituted phenyl amino propanamides exhibit anticonvulsant effect and reduce inward sodium ion current (NaV1.6)

Abstract This research studied the anticonvulsant properties of three synthesized isomers of dichloro-substituted phenyl amino propanamides in rodents and determined their effects on votage-gated sodium channels (NaV1.6) stably expressed in Human Embryonic Kidney (HEK Cells 293). 2,3-, 2,5- and 3,4- Dichloro anilines were reacted with acrylamide according to Michael-type addition reaction to obtain their corresponding isomers; DCP23, DCP25 and DCP34. Each isomer was evaluated for anticonvulsant effects using maximal electroshock (MES)- and pentylenetetrazole (PTZ)- induced seizure models in mice; tested against PTZ-induced kindling in rats and its synergistic effect with fluphenamic acid in mice. Effects of DCP23 and DCP25 were studied on voltage-gated sodium channels (NaV1.6) at different states of the channel, using electrophysiology techniques. The test compounds generally offered dose dependent protection against maximal electroshock- and pentylenetetrazole (PTZ)- induced seizure; demonstrated synergistic effect when co-administered with fluphenamic acid; and produced significant (p < 0.05) decrease in seizure progression in PTZ-kindled rats. DCP23 and DCP25 reduced sodium currents at different channel states in a concentration dependant manner. The results of this study showed that the compounds possess anticonvulsant effects and reduced the inward sodium currents. Therefore, they could exert anticonvulsant activity via sodium channels blockade.