Effects of Combinational Stimulation on Differentiation of MSCs into Osteoblasts

In this study, we investigated the effects of combinational stimulation consisting of cyclic tension and intermittent hydrostatic pressure (IHP) on the differentiation of mesenchymal stem cells (MSCs) into osteoblasts without biochemical agents. For this, we designed a novel bioreactor which can engage tensile stimuli and IHP simultaneously. We classified experimental groups based on types of stimulation such as NS (no stimuli), IHP (intermittent hydrostatic pressure), TS (tension stimuli), and CS (combinational stimulation). After engaging stimulation, we conducted various biological analyses, DNA contents, alkaline phosphatase (ALP) activity, von Kossa staining. As results, higher DNA contents were observed in the groups under mechanical stimulation regardless of its type than control group. And amounts of ALP normalized by DNA contents in the groups of IHP and TS were higher than those in group CS. Von Kossa staining in groups of IHP and TS showed higher mineral deposition than those in group CS. As a result, single stimulation such as IHP or tensile stimulation showed positive effects, but the combinational stimulation did not show comparable effects on the osteogenesis of MSCs.