Evaluation of the Cytotoxicity of Levodopa and its Complex with Hydroxypropyl-ßCyclodextrin (HP-ß-CD) to an Astrocyte Cell Line

Abstract

A simple, reliable a 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxy-phenyl)-2-(4- sulfophenyl)-2H-tetrazolium, (MTS) assay was conducted to evaluate the potential cytotoxic effects of levodopa, a “gold standard therapy” for Parkinsonism, and its complex with Hydroxypropyl-?Cyclodextrin(HP-?-CD)onanastrocyte cellline.The cells were incubatedina rangeof concentrations from 4.69 to 300 µg/mL levodopa, HP-?-CD or the complex for up to 72 hours. At every 24-hour interval, the optical density (OD), which reflects the number of viable cells, was recorded. In general, linear dose-dependent cytotoxicity profiles were observed for the cells subjected to levodopa or the complex, whereas a slightly triphasic response was observed for the cells exposed to HP-?-CD. A significant difference (P < 0.05) in cytotoxicity was detected between the HP-?-CD-treated group and the levodopa-treated group. In particular, we observed that the cells treated with the complex, even at the highest concentrations (> 200 µg/mL), exhibited improved tolerability in a time-dependent manner, which may indicate the potential ability of HP-?-CD to mask the toxic effects of levodopa via complexation.