Evaluation of hepatoprotective activity of methanol stem bark extract of Haematostaphis barteri Hook. F. against paracetamol and carbon tetrachloride-induced liver injury in rats

Background: The ethnomedical uses of Haematostaphis barteri commonly known as blood plum has been documented in literature. The efficacy of its stem bark extract in management of liver diseases is well acclaimed among communities of Northern Nigeria. Objective: To evaluate the hepatoprotective activity of methanol stem bark extract of Haematostaphis barteri against paracetamol and carbon tetrachloride (CCl4)-induced hepatotoxicity in Wistar rats. Methodology: Phytochemical and acute toxicity studies were carried out. Liver damage was induced in different groups of Wistar rats using paracetamol (3 g/kg) and 1 ml/kg of CCl4 (1:1 in olive oil). The effect of Haematostaphis barteri extract was tested for hepatoprotective activity by evaluating serum biochemical parameters and liver histology. The extract was also tested for antioxidant activity using in-vitro DPPH free radical scavenging method. Results: Phytochemicals present include tannins, sterols, alkaloids, saponins, triterpenes, flavonoids and anthraquinones. Oral median lethal dose was estimated to be >5000 mg/kg. Pre-treatment with the extract (250, 500 and 1000 mg/kg) significantly (p<0.05) reduced alanine aminotransferase and alkaline phosphatase levels compared to paracetamol and CCl4 toxic groups respectively. These results were supported by the protection against hepatocellular necrosis in the extract treated groups as well as the DPPH radical scavenging activity. Conclusion: The results obtained suggest the stem bark extract of Haematostaphis barteri possesses hepatoprotective activity. Keywords: Haematostaphis barteri, Hepatoprotective, Paracetamol, Carbon tetrachlorid

Anti-nociceptive and anti-inflammatory activities of methanol root extract of Andropogon gayanus Kunth (Poaceae) in rodents

Background: Andropogon gayanus is widely used in traditional medicine for various ailments such as postpartum pain, bronchitis and oedema. Objective: This study evaluated the anti-nociceptive and anti-inflammatory activities of methanol root extract of A. gayanus in experimental rodents. Methods: Phytochemical screening tests and acute toxicity studies were carried out. Analgesic activity using acetic acid-induced writhing response and hot plate test in mice, formalin-induced pain and carrageenan-induced paw oedema in rats were evaluated at doses of 250, 500 and 1000 mg/kg of the extract. Results: Oral median lethal dose was >5000 mg/kg in both mice and rats. The extract significantly (p<0.01) decreased the number of writhing movements at all tested doses. It also significantly (p<0.05) increased the mean reaction times. A significant (p<0.05) decrease in mean pain scores was also observed in both phases of the formalin test at 1000 mg/kg. The extract at 1000 mg/kg significantly (p<0.05) reduced the oedema at the 1st hour, while at the 5th hour, all doses tested significantly reduced the oedema. Conclusion: The methanol root extract of Andropogon gayanus possesses antinociceptive and anti-inflammatory activities. Keywords: Andropogon gayanus, Analgesic, Anti-inflammatory, Pai

Anticonvulsant activity of methanol stem bark extract of Boswellia dalzielii Hutch. (Burseraceae) in mice and chicks

Background: Boswellia dalzielii is a widely used medicinal plant in African traditional medicine. The efficacy of its stem bark extract in management of convulsions is well acclaimed among communities of Northern Nigeria. Objective: To evaluate the anticonvulsant potentials of methanol stem bark extract of Boswellia dalzielii in mice and chicks. Methodology: Phytochemical screening, elemental analysis and acute toxicity studies was carried out. The extract was evaluated for anticonvulsant activity against electrically-induced seizures in chicks and against pentylenetetrazole, strychnine, picrotoxin and 4-aminopyridine-induced seizures in mice at doses of 20, 40 and 80 mg/kg. Results: The intraperitoneal LD50 was estimated to be 280 and 570 mg/kg in mice and chicks respectively. The extract at 20 mg/kg provided 40% protection and significantly (p<0.05) increased the mean onset of seizure in MEST. A dose-dependent and significant (p<0.05) increase in the mean onsets of pentylenetetrazole and strychnine-induced seizures were produced by the extract at 80 mg/kg. Similarly, a dose-dependent and significant increase (p<0.05 and p<0.01) in latency to picrotoxin-induced convulsions was observed at 40 and 80 mg/kg respectively. Conclusion: These findings suggests the methanol stem bark extract of Boswellia dalzielii possesses anticonvulsant activities and thus supports the ethnomedical rationale for its use against convulsions. Keywords: Anticonvulsant, Boswellia dalzielii, Epilepsy, Pentylenetetrazole, Picrotoxi

Evaluation of analgesic and behavioural effects of ethanol root bark extract of Erythrina senegalensis DC (Fabaceae)

Background: The ethnomedicinal uses of Erythrina senegalensis including its antinociceptive and sedative properties have been documented in literature. Objective: This study evaluated the analgesic and behavioural effects of the ethanol root bark extract of E. senegalensis in mice. Methodology: Phytochemical screening and acute toxicity studies were conducted. Analgesic activity in mice was assessed using acetic acid induced writhing and hot plate method, while behavioural effects were evaluated using diazepam-induced sleeping test and hole-board test. These evaluations were carried out on E. senegalensis ethanol root bark extract at doses of 75, 150 and 300 mg/kg. Results: The intraperitoneal median lethal dose was found to be 1,137 mg/kg, while alkaloids, flavonoids, saponins, tannins and reducing sugars were found to be present in the plant material. E. senegalensis ethanol root bark extract at 150 and 300 mg/kg exhibited significant (p< 0.001) analgesic activity which offered 17.6% and 25.8% inhibition above ketoprofen in the acetic acid test respectively. At 300 mg/kg, E. senegalensis ethanol root bark extract demonstrated comparative analgesia with pentazocine in hot plate test. At the same dose, it produced a significant (p< 0.05) potentiation of diazepam-induced sleeping time. A significant increase in number of head-dips was demonstrated by E. senegalensis ethanol root bark extract at 150 mg/kg. Conclusion: The study shows that E. senegalensis ethanol root bark extract possesses analgesic, sedative and anxiolytic principles, thus supporting the ethnomedicinal rationale for its uses in management of painful conditions and sleep disturbances. Keywords: Erythrina senegalensis, analgesic, sedative, behavioura

Anti-hyperglycaemic activity of tuber extract of Chlorophytum alismifolium Baker in streptozotocin-induced hyperglycaemic rats

The tubers of Chlorophytum alismifolium (Liliaceae) are widely used in Nigerian Herbal Medicine to treat diabetes mellitus and their efficacy is widely acclaimed among the rural communities of Northern Nigeria. This study was aimed at investigating the antihyperglycaemic potential of the tuber extract of Chlorophytum alismifolium (CAE) in streptozotocin-induced hyperglycaemic rats. Phytochemical screening and oral median lethal dose (LD50) estimation of CAE in rats were carried out. Antihyperglycaemic screening of the extract (at oral doses of 150, 300 and 600 mg/kg) was performed using normal and streptozotocin-induced hyperglycaemic rats for 28 days. Fasting blood glucose levels were measured and serum lipids were analyzed. Liver, kidney, heart and pancreatic tissues were examined for histopathological damages using standard histological processing. Phytochemical screening revealed the presence alkaloids, saponins, flavonoids, triterpenes and glycosides. Oral LD50 was estimated to be >5000 mg/kg body weight in rats. C. alismifolium extract at all the doses tested showed blood glucose lowering effect. Statistical significant (p < .01) blood glucose lowering effect at 150 mg/kg on day 21, at 300 mg/kg on days 21 and 28 (p < .001 and p < .01 respectively) and 600 mg/kg on days 7, 14, 21 and 28 (p < .05, p < .01, p < .001 and p < .01 respectively) was produced by the extract. The extract also reduced the levels of total cholesterol, triglycerides and low density lipoprotein. Histopathological examination of the pancreas showed restoration of pancreatic islet cells at the doses of 300 and 600 mg/kg of the extract. In conclusion, the results obtained suggest the tuber extract of Chlorophytum alismifolium possesses antihyperglycaemic activity