Development of beta-carotene-loaded poly(lactic acid)/hydroxyapatite core-shell nanoparticles for osteoblast differentiation

ABSTRACT Beta-carotene (BC) is a nutrient in vegetables and a precursor of vitamin A. BC has been reported to have anticarcinogenic, antiaging, and antioxidation properties and prevents heart diseases. Recently, BC has gained significant attention due to stimulating effect on osteoblast differentiation. Poly(lactic acid)/hydroxyapatite (PLA/HAp) core-shell nanoparticles have been reported earlier with a load capacity of 250% for water-insoluble substances, using a surfactant-free emulsification method. In this work, PLA/HAp core-shell nanoparticles loaded with BC were prepared, and osteoblast differentiation behavior was evaluated. BC was successfully loaded into PLA/HAp core-shell nanoparticles with diameters of approximately 30 nm. BC/loaded PLA/HAp core-shell nanoparticles stimulated osteoblast differentiation by upregulating collagen type I, osteopontin, and osteocalcin expression. In addition, the gene expression levels of these osteoblasts were significantly larger than those stimulated by PLA/HAp core-shell nanoparticles without BC and cultured in a differential medium (with ascorbic acid and β-glycerophosphate). PLA/HAp core-shell nanoparticles showed satisfactory cytocompatibility because they were attached to the osteoblasts. Consequently, BC was effectively delivered to osteoblasts by nanoparticles. These results suggested that BC-loaded PLA/HAp core-shell nanoparticles could enhance bone formation. Graphical Abstract