Pharmacokinetics, Biodistribution, Excretion and Plasma Protein Binding Studies of Acteoside in Rats

Acteoside is a representative phenylethanoid glycoside, exhibiting great potency in neurodegenerative diseases treatment, such as Alzheimer's disease. This study was aimed to explore the pharmacokinetic characteristics, tissue distribution, excretion and plasma protein binding of acteoside in Sprague-Dawley rats after oral administration at 20, 40 and 80 mg/kg by a validated LC-MS/MS method. Acteoside was absorbed quickly after oral administration at 3 dose levels. Acteoside reached the peak concentration at 0.29±0.17 h, exhibiting a maximum concentration (Cmax) of 312.54±44.43 ng/mL after oral administration at 40 mg/kg, and the elimination half-life was 1.05±0.23 h. Both the Cmax and AUC showed a linear increase with the oral doses administered. The absolute bioavailability of acteoside was only around 1%. After oral administration, acteoside was extensively and rapidly distributed in most tissues including brain, but little amount of acteoside was excreted in urine, bile or feces. And the rat plasma protein binding ratio with equilibrium dialysis was about 60%. The pharmacokinetic characteristics of the fast gastro-intestinal absorption, the noteworthy distribution in most tissues including brain, the absence of acteoside in urine, bile and feces and valuable plasma protein binding ratio in rats will provide important reference for further research.