This study assessed the effects of 808 nm diode laser on the gene expression of receptor activator of nuclear factor kappa beta ligand (RANKL) and osteoprotegerin (OPG), key regulators of bone remodeling, in exosomes derived from osteoblast-like cells.

The cultured MG63 cells were subjected to 808 nm diode laser irradiation at energy densities of 3 J/cm², 6 J/cm², and 9 J/cm², along with a control group with no intervention. The irradiation sessions were conducted twice, with a 24-hour interval between them. Next the exosomes from the target cells were isolated, and the mRNA levels of the RANKL and OPG genes were assessed using qPCR.

The OPG mRNA level in exosomes extracted from cells exposed to 9 J/cm² was found to be significantly elevated compared to both the control group and 6 J/cm². Conversely, the mRNA level of RANKL in group exposed to 9 J/cm² was significantly reduced in comparison to the control group and 6 J/cm². Additionally, the RANKL mRNA level in 6 J/cm² was also significantly lower than that observed in the control group and 3 J/cm².

Using 808 nm diode laser at an energy density of 9 J/cm² resulted in an upregulation of exosomal mRNA for OPG and a downregulation of RANKL. Photobiomodulation may enhance bone regeneration via exosomal signaling. Considering the promising clinical application of exosomes in bone regeneration, our results highlight the potential of photobiomodulation to manipulate exosomal content for therapeutic purposes.