Enhanced cellular uptake and osteogenic differentiation efficiency of melatonin by inclusion complexation with 2-hydroxypropyl β-cyclodextrin

In this study, an inclusion complex of MLT with 2-hydroxypropyl β-cyclodextrin (HP-β-CD) was prepared to improve the water solubility, and the osteogenic differentiation ability of the inclusion complex was investigated in MC3T3-E1 cells. The formation of HP-β-CD/MLT inclusion complex was confirmed by 1H and 13C nuclear magnetic resonance spectroscopy and wide-angle X-ray diffraction. The water solubility of MLT increased linearly upon addition of HP-β-CD because of the formation of the inclusion complex. Additionally, treatment of the cells with HP-β-CD/MLT inclusion complex showed higher uptake amount of MLT than that treated with free MLT. In addition, treatment of MC3T3-E1 cells with HP-β-CD/MLT inclusion complex increased alkaline phosphatase activity and mineralized matrix deposition, compared to that in free MLT-treated and untreated cells. Furthermore, cells treated with HP-β-CD/MLT inclusion complex exhibited higher expression levels of osteogenic differentiation genes than those in the untreated and free MLT-treated cells. Accordingly, these results suggested that inclusion complexation of MLT with HP-β-CD would be a potential formulation for bone regeneration because of its improved solubility and enhanced osteogenic differentiation efficiency. Graphical abstract
Source: International Journal of Pharmaceutics - Category: Drugs & Pharmacology Source Type: research