Toxicological profiles of direct administration of extract of gossypium barbadense(Linn) leaves.
This study investigated the acute and sub-chronic toxicities of direct administration of leaves of Gossypium barbadense Linn. with and without addition of lime in albino mice and wistar rats respectively. This was with a view to evaluating its possible toxic effects on animals. Fresh leaves of G.barbadense were crushed and squeezed to obtain direct-extract while the limed-extract was prepared from the mixture of direct-extract and Citrus medica juice in ratio 3:1[v/v]. The direct and limed-extract were then partitioned with ethylacetate to obtain ethylacetate fractions which was used for cytotoxicity test. The direct and limed-extracts were screened for phytochemical constitutents. Acute toxicity study was carried out by standard procedure, using mice of weight range of between 19 kg and 25 kg, while in sub-chronic toxicity adult wistar rat of weight range 110 kg and 150 kg were used.The animals were treated with 250 and 500 mg/kg of direct and limed-extract of G. barbadense, for sub-chronic study, every other day for a period of 30 days after which the animals were sacrificed; blood was collected and liver and kidney were excised from each animal. Changes in body weight and organ weight were noted at the end of the experiment. Haematological and biochemical parameters were analyzed in the blood while histological examination was carried out on liver and kidney using standard methods. The total protein concentration in the plasma and liver homogenates were determined using standard procedure. The plasma albumin, bilirubin, urea and creatinine concentration were determined. Alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyltransferase activities were assayed in the liver. Cytotoxicity was carried out using Allium cepa with different concentrations (2.5, 5 and 10 mg/ml) of ethylacetate fraction from direct and limed-extracts.The roots of Allium cepa were harvested and homogenized with normal saline to obtain supernatant for biochemical analyses. The results indicated that the median lethal dose (LD50) would be above 5000 mg/kg of body weight since no mortality was recorded in acute study. Changes in body weight were observed after 30 days of sub-chronic study. Biochemical indices of plasma and liver homogenates, alanine aminotransferase (ALT), aspartate aminotransferase (AST) and albumin were lower in the test animals compare with the controls. In contrast, totalprotein concentrations in both plasma and liver homogenate were higher in test groups than in control.Bilirubin concentration was also higher in all the treated animals.The difference was significant at (p<0.05) for the animals treated with direct extract. Haematological parameters maintained nearly the same level with control in all the treated groups. Additionally, the cytotoxicity test using Allium cepa suggested that direct-extract and ethylacetate fractions were cytotoxic but addition of lime appeared to have lowering effects on the cytotoxicity in the treatment. However, the histological study of the liver did not reveal any damage but the kidney histology indicated partial glomerulus degeneration for animals treated with 250 mg/kg bwt in both direct- and limed-extracts. The study concluded that both direct and limed-extract of the leaves of G. barbadense were not toxic on animals at 250 mg/kg and 500 mg/kg body weight. However, the ethylacetate fractions obtained from both direct- and limed-extract exhibited some degree of toxic effect.