Protective activities of the aqueous root extract of Harungana madagascariensis in acute and repeated acetaminophen hepatotoxic rats
In the current in vivo experimental study, the protective activities of oral 100–500mg/kg/day of the aqueous root extract of Harungana madagascariensis L. were investigated in the acute and repeated acetaminophen-induced hepatotoxicities in adult Wistar rats by assaying their effects on the serum levels of alanine and aspartate aminotransferases (ALT and AST, respectively), alkaline phosphatase (ALP), total and conjugated bilirubin (TB and CB, respectively), triglycerides (TG), total cholesterol (TC), cholesterol fractions (HDL-c, LDL-c, VLDL-c), fasting blood glucose (FBG), total protein (TP) and albumin (ALB). Results showed that acute intraperitoneal injection of 800mg/kg of acetaminophen induced significant (p<0.001) elevations in the serum concentrations of ALT, AST, ALP and FBG but caused significant (p<0.001) decreases in the serum concentrations of TP and ALB with non-significant (p>0.05) alterations in the serum levels of lipids, TB and CB. However, pretreatments with the extract significantly (p<0.05, p<0.01, p<0.001) attenuated elevations of ALT, AST, ALP and FBG, while significantly (p<0.05, p<0.01, p<0.001) attenuating reductions in the serum TP and ALB levels. In the repeated dose model, similar effects were recorded in the measured parameters except that there was significant (p<0.001) hypoglycemia and increases in the serum TB and CB. Oral pretreatments with the extract significantly (p<0.001) enhanced acetaminophen induced hypoglycemia while significantly (p<0.05, p<0.01) attenuating elevations in the serum levels of TB and CB, in dose related fashion. Acetaminophen hepatotoxicity was also characterized by moderate-to-severe hepatic necrosis which was equally attenuated by the extract. Thus, the recorded biochemical and histopathological attenuations could be due to the presence of active principle(s) contained in the extract.