Low intensity lasers differently induce primary human osteoblast proliferation and differentiation

Author(s)

Oliveira, Flavia A. ; Matos, Adriana A. ; Santesso, Mariana R. ; Tokuhara, Cintia K. ; Leite, Aline L. ; Bagnato, Vanderley S. ; Machado, Maria A. A. M. ; Peres-Buzalaf, Camila ; Oliveira, Rodrigo C.

• Document type: Journal article
• Source: JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY; v. 163, p. 14-21, OCT 2016.
• Web of Science Citations: 16

Abstract

Among various compounds used in research and clinic for degenerative bone diseases, low level laser therapy (LLLT), comprising low level lasers (LLL) and light emitting diodes (LEDs), has been investigated regarding its effects on bone metabolism. They have specific wavelengths but in general act as a cellular biomodulator, and as a therapeutic agent, rebalancing and normalizing their activity. However, they are not standardized yet, since their parameters of use are relevant for the effects and mechanisms of action. Therefore, the aim of this study was to compare the influence of two spectrums of LLL and LED phototherapy, at the same energy densities (10 and 50 J/cm(2)), on human osteoblasts proliferation and differentiation. The involvement of ERK signaling on proliferation was also investigated by evaluating its activation during proliferation under different phototherapies by western blotting and CFSE-based osteoblast proliferation was measured in a presence or absence of the ERIC-specific inhibitor. Osteogenic differentiation was evaluated through in vitro mineralization and gene expression of type I collagen (COL1A1) and osteonectin (SPARC) by Real Time- PCR. Increases in viable cells and proliferation were obtained after irradiation, regardless of LLLT type. However, only red at 10 J/cm2 and infrared at both doses, but not LED, induced ERK1/2 activation. In the presence of ERK inhibitor, the LLL-induced proliferation was prevented. In addition, while COL1A1 gene expression was upregulated by red laser, SPARC does so by infrared stimulation. However, LED, at both doses, increased both COL1A1 and SPARC expression. All LLLT increased mineralization, dependent on the dose and time. Thus, LLL and LED differently modulated the metabolism of human osteoblasts, increasing proliferation by mechanism dependent or not of ERK signaling activation and osteogenic differentiation markers. (C) 2016 Elsevier B.V. All rights reserved. (AU)

• FAPESP's process: 08/11261-1 - Evaluating the influence of laser irradiation on low intensity in the expression of RANKL and OPG in osteoblasts in vitro.
• Grantee: Adriana Arruda Matos
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• FAPESP's process: 07/08367-0 - Evaluation of the influence of the irradiation with laser in low intensity in the proliferative and metabolic behavior of human osteoblasts in vitro
• Grantee: Camila Peres Buzalaf
• Support Opportunities: Regular Research Grants
• FAPESP's process: 08/11391-2 - EFFECT OF RADIATION WITH LOW INTENSITY LASER IN THE PRE-OSTEOBLAST IN VITRO: CELL VIABILITY AND MMPS -2 AND -9 EXPRESSION ANALYSIS.
• Grantee: Flávia Amadeu de Oliveira
• Support Opportunities: Scholarships in Brazil - Scientific Initiation