PIPERINE, A PLANT ALKALOID OF THE PIPER SPECIES, ENHANCES THE BIOAVAILABILITY OF AFLATOXIN-B1 IN RAT-TISSUES

Piperine is known to modify the biotransformation of drugs. The effect of piperine on the metabolic activation and distribution of [H-3]-aflatoxin B1 (AFB1) in rats has been described. Piperine markedly inhibited liver microsome-catalysed [H-3]AFB1 binding to calf thymus DNA in vitro, in a dose dependent manner. Rats pretreated with piperine accumulated considerable [H-3]AFB1 radioactivity in plasma and in the tissues examined as compared to the controls. However, piperine had no influence on hepatic [H-3]AFB1-DNA binding in vivo, which could possibly be due to the null effect of piperine on liver cytosolic glutathione (GSH) 5-transferase activity. Piperine-treated rat liver microsomes demonstrated a tendency to enhance [H-3]AFB1 binding to calf thymus DNA in vivo. The effect of piperine on AFB1 metabolism thus closely resembles the mode of action of SKF 525-A on biotransformation of foreign compounds.