ABSTRACT
The aim of this study was to investigate the prophylactic and curative effects of an alkaloid-rich fraction of Abrusprecatorius seedchloroform-methanol extract on paracetamol-induced hepatotoxicity in rats. The percentage yield of the methanol extract of Abrusprecatorius seeds was found to be 2.08% w/w. Further purification of the extract using Sephadex gel G15 to get a purer sample was done. The fractions were spotted on a TLC plate and was spread with Drangendoff’s reagent in which some fractions turned purple indicating the presence of alkaloids. The fractions that turned purple were pulled into a beaker and called fraction I which gave a percentage yield of17.75% and was used in this study. The qualitative phytochemical analysis of fraction Irevealed a wide range of phytochemicals such asalkaloids, flavonoids, saponins, glycosides, tannins and carbohydrates, steroids, terpenoids, and peptides which could be physiologically potent in ameliorating several diseases. The quantitative phytochemical analysis of fraction I of Abrusprecatoriusseed methanol extract showed the presence of alkaloids (5480 ± 184 mg/100g), flavonoids (215 ± 97 mg/100g), saponins (2.98 ± 1.33 mg/100g) and tannins (6.4 ± 0.72 mg/100g). Hepatotoxicity was induced using paracetamol (2500 mg/kg b.w.) orally. For prophylactic treatment (hepato-protective), administration of extract was done for 7 days before paracetamol induction and collection of blood was done after 24 hours of administration. Curative treatment (hepato-curative) was done after paracetamol induction at day 0 and treatment was done for 14 days. Blood was collected on days 8 and 15 for the analyses.Prophylactic and curative treatments with fraction I of Abrusprecatorius methanol extract at the dose of 100 and 200mg/kg b.w for group 4 and 5 produced a significant decrease (p˂0.05) in the activities of the liver marker enzymes (ALP, AST, ALT) and bilirubin levels in a dose- and time-dependent manner compared to the paracetamol untreated group 2 (positive control).Groups 3, 4, and 5 treated with 100 mg/kg b.w.silymarin (standard hepato-protective and curative drug),100mg/k.g. b.w. of fraction I and 200mg/k.g. b.w. of fraction I respectively before and after paracetamol induction caused a significant decrease (p˂0.05) in the serum urea and creatinine concentrations of both hepato-protective and hepato-curative groups compared to the positive control. Serum electrolyte concentrations showed a significant increase (p˂0.05) in the treated groups of both hepato-protective and curative when compared to the positive control.The MDA concentration decreased significantly (p˂0.05) in the treated groups and standard groups compared to the positive control after 24 hours (hepato-protective)and at day 8 and 15 (hepato-curative). Serum SOD activity of both protective and curative models, showed adose- and time-dependent significant increase (p˂0.05) in the treated groups compared to the positive control. The haematological parameters of the rats treated with fraction I of Abrusprecatorius methanol extract at various dosesshowed a significant increase (p˂0.05) in the PCV levels, Hb concentration and RBC count compared to the positive control. A dose- and time-dependentsignificant decrease (p˂0.05) was observed in the WBC count of all treated groups (hepato-protective and hepato-curative) compared to the positive control. The test groups that received fraction I of Abrusprecatoriusin both models showed a dose- and time-dependent effects on the biochemical markers used in the study similar to the standard drug. However,fraction I had more curative effect than protective but silymarinwas more potent.
