mRNA of Expression of Per 1 in Mice Bone Marrow Mesenchymal Stem Cells Irradiated by Red Laser

A core group of circadian genes regulate the circadian rhythms in mammalian cells. However, the mammalian cellular circadian rhythm in photobiomodulation remains unknown. A lot of evidence has shown that >20% of expressed mRNAs in bone stissues oscillate in a circadian manner. The aim of this paper is to investigate the mRNA expression of period 1 (per 1) in murine bone marrow-derived mesenchymal stem cells (BMSCs) which were irradiated by 635 nm red laser light. The cells were seeded in 35mm tissue-culture dishes at a density of 8 × 104 cells/dish and cultured in Dulbecco’s modified Eagle’s medium (DMEM). BMSCs were irradiated once by 635 nm red light with radiation energies 0 J/cm2, 1 J/cm2, 4 J/cm2. mRNA expression of per 1 via Semi-Quantitative Real-time RT-PCR at 0h, 6 h, 12 h, 18 h, 24 h. The genes displayed a oscillatory period of nearly 24 hours. And 635 m laser light changed the mRNA expression of per 1. We conclude that red light irradiation can affect the circadian rhythm of BMSCs.