Comparison of the alendronate and irradiation with a light-emitting diode (LED) on murine osteoclastogenesis

Abstract

Photomodulation therapy (PBMT) using light-emitting diode (LED) has been proposed as an alternative to conventional osteoporosis therapies. Our aim was to determine the effect of irradiation with a light-emitting diode on receptor activator of NF-κB ligand (RANKL)-mediated differentiation of mouse bone marrow macrophages into osteoclasts and compare it to alendronate treatment. The cells were irradiated with LED at 635±10 nm, 9-cm spot size, 5 mW/cm, and 18 J for 60 min/day in a CO incubator. The differentiation of irradiated and untreated RANKL-stimulated bone marrow macrophages into osteoclasts was evaluated by tartrate-resistant acid phosphatase (TRAP) staining and by molecular methods. These included assessing messenger RNA (mRNA) expression of osteoclastic markers such as TRAP, c-Fos, Atp6v0d2, DC-STAMP, NFATc1, cathepsin K, MMP9 and OSCAR; phosphorylation of various MAPKs, including extracellular signal-regulated kinase ERK1/2, P38, and JNK; NF-κB translocation; and resorption pit formation. Results were compared to those obtained with sodium alendronate. Production of reactive oxygen species was measured by a 2',7'-dihydrodichlorofluorescein diacetate assay. LED irradiation and alendronate inhibited mRNA expression of osteoclast-related genes, such as TRAP, c-Fos, and NFATc1, and reduced the osteoclast activity of RANKL-stimulated bone marrow macrophages. LED irradiation, but not alendronate, also inhibited the production of reactive oxygen species (ROS); phosphorylation of ERK, P38, and IκB; and NF-κB translocation. These findings suggest that LED irradiation downregulates osteoclastogenesis by ROS production; this effect could lead to reduced bone loss and may offer a new therapeutic tool for managing osteoporosis.

The Effects of Photobiomodulation on MC3T3-E1 Cells via 630 nm and 810 nm Light-Emitting Diode

“…Beyond its effects on osteoblasts, some studies have also demonstrated the potential of PBM to inhibit osteoclastogenesis [41,42]. Reduced ROS production has been proposed as a possible cause of reduced osteoclastogenesis following irradiation [41–43].…”

“…Beyond its effects on osteoblasts, some studies have also demonstrated the potential of PBM to inhibit osteoclastogenesis [41,42]. Reduced ROS production has been proposed as a possible cause of reduced osteoclastogenesis following irradiation [41–43]. Moreover, many studies found that PBM could promote bone healing and improve bone quantity and strength in ovariectomized rats [39,40,44–46], in which near infrared light was more commonly used.…”

Regulation of Osteosclerosis by Inoculated Cd133+ PC3 Cells in Bone‐marrow Microenvironmental Niches

“…The sequences of the primers used to target various genes are shown in Table . Details of the reaction system and amplification procedures have been described previously …”

“…Details of the reaction system and amplification procedures have been described previously. (24) Luciferase reporter assay BMSCs were transiently transfected with a Runx2 or OSX target sequence-linked luciferase reporter plasmid using Lipofectamine (Invitrogen), according to the manufacturer's instructions. After transfection, cells were incubated in the designated medium for 7 days.…”

Histopathologic evaluation of the effects of local simvastatin application and photobiomodulation by light-emitting diode on bone healing of rat calvarial defects

“…Low-intensity light therapy, ordinarily referred to to as photombiomodulation (PBM) by light in the far-red to near-infrared (NIR) region of the spectrum (630-1000 nm), stimulates several cellular functions. PBM therapy has been shown to downregulate osteoclastogenesis, increase the cell proliferation including that of fibroblasts and to promote angiogenesis thus accelerating the bone repair process [1,2,16]. The use of light-emitting diodes (LEDs) and low level lasers (LLLs) are favourable therapeutic approaches in the treatment of infected and hypoxic wounds [17,18].…”