title: Photobiomodulation (blue and green light) encourages osteoblastic-differentiation of human adipose-derived stem cells: role of intracellular calcium and light-gated ion channels.
abstract: Human adipose-derived stem cells (hASCs) have the potential to differentiate into several different cell types including osteoblasts. Photobiomodulation (PBM) or low level laser therapy (LLLT) using red or near-infrared wavelengths has been reported to have effects on both proliferation and osteogenic differentiation of stem cells. We examined the effects of delivering four different wavelengths (420 nm, 540 nm, 660 nm, 810 nm) at the same dose (3 J/cm(2)) five times (every two days) on hASCs cultured in osteogenic medium over three weeks. We measured expression of the following transcription factors by
  
  
  
  RUNX2, osterix, and the osteoblast protein, osteocalcin. The 420 nm and 540 nm wavelengths were more effective in stimulating osteoblast differentiation compared to 660 nm and 810 nm. Intracellular calcium was higher after 420 nm and 540 nm, and could be inhibited by capsazepine and SKF96365, which also inhibited osteogenic differentiation. We hypothesize that activation of light-gated calcium ion channels by blue and green light could explain our results.
authors.affiliation: Center of Digital Dentistry, Peking University School and Hospital of Stomatology, Beijing, China.|National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing, China.|Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, MA, 02114, USA.|Department of Dermatology, Harvard Medical School, Boston, MA, 02115, USA.
authors.forename: Yuguang
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, MA, 02114, USA.|Department of Dermatology, Harvard Medical School, Boston, MA, 02115, USA.
authors.forename: Ying-Ying
authors.initials: YY
authors.lastname: Huang
authors.affiliation: Center of Digital Dentistry, Peking University School and Hospital of Stomatology, Beijing, China.|National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Center of Digital Dentistry, Peking University School and Hospital of Stomatology, Beijing, China.|National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing, China.
authors.forename: Peijun
authors.initials: P
authors.lastname: Lyu
authors.affiliation: Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, MA, 02114, USA.|Department of Dermatology, Harvard Medical School, Boston, MA, 02115, USA.|Harvard-MIT Division of Health Sciences and Technology, Cambridge, MA, 02139, USA.
authors.forename: Michael R
authors.initials: MR
authors.lastname: Hamblin
mesh_terms: D000273:Adipose Tissue / Q000166:cytology / Q000378:metabolism*; D000943:Antigens, Differentiation / Q000096:biosynthesis*; D002118:Calcium / Q000378:metabolism*; D002454:Cell Differentiation / Q000528:radiation effects*; D006801:Humans; D015640:Ion Channel Gating / Q000528:radiation effects*; D007473:Ion Channels / Q000378:metabolism*; D007834:Lasers; D008027:Light; D010006:Osteoblasts / Q000166:cytology / Q000378:metabolism*; D013234:Stem Cells / Q000166:cytology / Q000378:metabolism*
chemical_list: D000943:Antigens, Differentiation; D007473:Ion Channels; D002118:Calcium