The histological and biochemical effects of sorghum bicolor stem bark on paracetamol- induced liver damage in wistar rats (rattus norvegicus)
This study investigated the protective and ameliorative potential of aqueous extract of Sorghum bicolor stem bark against paracetamol–induced hepatotoxicity in rats. Thirty five adult Wistar rats weighing 150 to 200g were randomized into seven groups of five animals each. Group A (control) received distilled water of equal volume to extract (1ml), group B received 200mg/kg body weight. (bw) aqueous extract of Sorghum bicolor stem bark for 7days, group C received 300mg/kg bw paracetamol for 1 day, group D received 300mg/kg bw paracetamol for 1 day plus aqueous extract of Sorghum bicolor stem bark (200mg/kg bw) for 7 days, group E received 300mg/kg bw paracetamol for 1 day plus silymarin (100mg/kg bw), group F received 200mg/kg bw aqueous extract of Sorghum bicolor stem bark for 7 days plus paracetamol (300mg/kg bw) for 1 day and group G received silymarin (100mg/kg bw) and paracetamol (300mg/kg bw). All solutions were administered orally for 8 days. At the end of the administration, animals were sacrificed under chloroform anesthesia, and blood samples collected via cardiac puncture. Blood samples were used to calculate concentrations of hemoglobin, red blood cells, and white blood cells, packed cell volume, mean haemoglobin volume, mean corpuscle haematocrit, and mean corpuscle haemoglobin concentration. Sera were obtained to assay the levels of liver enzymes including aspartate amino transferase, alanine amino transferase, alkaline phosphatase, and serum bilirubin, Paraffin sections of liver were stained for histology using hematoxylin and eosin, and for histochemistry using Masson’s trichome, Gordon & Sweets, and Periodic acid schiff’s staining techniques. Results showed that in group C there was congestion of hepatic portal triad, sinusoids were dilated, and there was necrosis of hepatocytes nuclei. In group B that was given aqueous extract of Sorghum bicolor stem bark only, liver architecture was normal, group D and G showed mild portal triad congestion, mild dilated sinusoids, presence of massive inflammatory cells, hepatocytes showed dysplastic changes, Group E an F showed mild portal triad congestion, mild dilated sinusoids, reduced inflammatory cells, and dysplastic changes. Group C showed significant increase in the activities of aspartate aminotransferase, alanine aminotransferase, bilirubin and alkaline phosphatase compared to each of group A and B (p<0.05). However, the level of these enzymes significantly reduced in groups D, E, F and G compared to group C (p<0.05). In comparison with the control group , there was no significant increase in the value of packed cell volume value across the experimental groups, but there was significant difference when compared with the extract only group (p<0.05). There was a significant increase in the hemoglobin and red blood cells of extract only group, when compare to the paracetamol–induced toxicity group (p<0.05), but there was no significant difference when compared to the other experimental groups and control. Other hematological parameters showed no significant difference across the all the groups (p>0.05). The results of this study indicated that toxic dose of paracetamol was hepatotoxic, and Sorghum bicolor stem bark extract had ameliorative and protective effect on the liver damage.