Toxicological evaluation of Catha edulis leaves: a long term feeding experiment in animals

In this study the long term (6 months) toxicological effect of varying levels of Catha edulis leaves were examined on the plasma concentration of liver enzymes as well as the histopathology of tissue sections of the liver. Both biochemical and histopathological data presented demonstrate signs of C. edulis toxicity. Our results show a significant increase in plasma levels of Alkaline phosphatase (ALP), Alanine aminotransferase (ALT) and Aspartate aminotransferase (AST) with all levels of C. edulis leaves tested and throughout the treatment period. The increase of ALP was more prominent than both ALT and AST at the higher level of 30%. Plasma levels of AST though were only moderately increased at the higher level of 30% at the early stage of treatment (3 months) it significantly increased with all levels of C. edulis leaves in the long term (4-6 months). In addition, a time-dependent gradual increase in indirect bilirubin with a concomitant decrease in direct bilirubin levels were observed with the lower level of C. edulis (10%) with no signs of haemolysis. Histopathology of tissue sections of liver display evidences of increasing chronic inflammation with porto-portal fibrosis in the tissue sections obtained from animals treated with both 20 and 30% C. edulis.