Irradiation by high-intensity red light-emitting diode enhances human bone marrow mesenchymal stem cells osteogenic differentiation and mineralization through Wnt/β-catenin signaling pathway.

Abstract

Photobiomodulation therapy (PBMT) using a light-emitting diode (LED) has been employed for various photomedicine studies. The aim of this study was to determine the effects of a high-intensity red LED on the proliferation and osteogenic differentiation of human bone marrow mesenchymal stem cells (BMSCs) and the related mechanism. BMSCs were subjected to high-intensity red LED (LZ1-00R205 Deep Red LED) irradiations for 0 to 40s with energy densities ranging from 0 to 8J/cm2. The distance from the LED to the cell layer was 40mm. The spot size on the target was 4cm2. Cell proliferation was measured at 3, 24, 48, and 72h. The effects of LED irradiation on osteogenic differentiation and mineralization were examined with a particular focus on the Wnt/β-catenin signaling pathway. The high-intensity red LED irradiations did not alter BMSC proliferation after 72h. LED exposure of 6J/cm2 (30s) led to significant enhancements of osteogenic differentiation and mineralization. Additionally, the high-intensity LED irradiation induced activation of Wnt/β-catenin. The effects of the high-intensity LED irradiation on BMSC osteogenic differentiation and mineralization were suppressed by treatment with the Wnt/β-catenin inhibitor XAV939. P < 0.05 was considered significant. The results indicate that high-intensity red LED irradiation increases BMSC osteogenic differentiation and mineralization via Wnt/β-catenin activation. Therefore, short duration irradiation with a portable high-intensity LED may be used as a potential approach in hard tissue regeneration therapy.