Effects of photobiomodulation on different phases of in vitro osteogenesis

• Published in: Photochemical & photobiological sciences Vol. 23; no. 8; pp. 1565 - 1571
• Main Authors: de Araújo, Priscila Pinto Brandão, Martinez, Elizabeth Ferreira, Garcez, Aguinaldo Silva, de Castro Raucci, Larissa Moreira Spinola, Soares, Andresa Borges, de Araújo, Vera Cavalcanti, Teixeira, Lucas Novaes
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01.08.2024
• Subjects: Biochemistry; Biomaterials; Chemistry; Chemistry and Materials Science; Original Papers; Physical Chemistry; Plant Sciences; Cell culture; Osteoblastic cells; Bone; Osteogenesis; Photobiomodulation
• ISSN: 1474-905X; 1474-9092; 1474-9092
• DOI: 10.1007/s43630-024-00616-4

The present study aimed to evaluate the effect of photobiomodulation therapy (PBM) on different stages of osteogenesis in vitro. For this, osteoblastic-like cells (Saos-2 cell lineage) were irradiated in two different periods: during the Proliferation phase (PP; from the second to the fourth day) and during the Differentiation phase (DP; from the seventh to the ninth day). The energy density used in the study was 1.5 J/ cm 2 . The following parameters were evaluated: 1) quantification of collagen type 1 (COL 1), osteopontin (OPN), and bone morphogenetic protein 2 (BMP-2); 2) quantification of alkaline phosphatase (ALP) activity; and 3) quantification of  extracellular matrix (ECM) mineralization. Non-irradiated cultures were used as controls. The data were analyzed using the Student's t-test or one-way ANOVA, considering a significance level of 5%. The results indicated that COL 1 and BMP-2 quantification was higher in Saos-2 irradiated during the DP in relation to the control group at day 10 ( p  < 0.05). No differences were observed for other comparisons at this time point ( p  > 0.05). OPN expression was greater in PP compared with the other experimental groups at day 10 ( p  < 0.05). Irradiation did not affect ALP activity in Saos-2 regardless of the exposure phase and the time point evaluated ( p  > 0.05). At day 14, ECM mineralization was higher in Saos-2 cultures irradiated during the DP in relation to the PP ( p  < 0.05). In conclusion, the results suggested that the effects of PBM on osteoblastic cells may be influenced by the stage of cell differentiation. Graphical Abstract