Efeitos da fotobiomodulação com luz vermelha associada a fatores de crescimento em fibroblastos dérmicos humanos

Abstract

Skin aging is a multifactorial process involving structural and functional alterations of the skin, resulting in loss of elasticity, decreased synthesis of collagen and elastin, greater fragmentation of the extracellular matrix, and impaired cell renewal. These changes lead to clinical signs such as sagging, wrinkles, and a more tired appearance, impacting not only aesthetics but also individuals’ quality of life and self-esteem. In this context, several strategies have been investigated to modulate fibroblast activity and restore extracellular matrix components. Among these, growth factors such as TGF-β and IGF stand out, as they play crucial roles in proliferation, differentiation, and the synthesis of collagen and elastin. Another approach is photobiomodulation (PBM) with red light (660 nm), which acts on mitochondria, increasing ATP production, modulating reactive oxygen species, and activating signaling pathways that may enhance collagen synthesis. However, the combined effect of both treatments remains unknown in the literature. Thus, the aim of this study was to evaluate, in an in vitro model, the effect of PBM with red light (660 nm) associated with growth factors (TGF-β3, IDP2, and IGF) on cell viability and the expression of extracellular matrix genes, including COL3A1, COL1A1, ELASTIN, and TGF-β, in human dermal fibroblasts (HFF-2).Methodology:HFF-2 fibroblasts were cultured in DMEM medium and divided into six experimental groups: control, growth factors (1:1 and 1:3), PBM alone, and PBM combined with growth factors (1:1 and 1:3). Irradiation was performed using a red LED (660 nm; 5.04 J/cm²). Cell viability was assessed using MTS and crystal violet assays after 24 h, 48 h, and 72 h, and gene expression (COL1A1, COL3A1, ELASTIN, and TGF-β) was quantified by RT- qPCR after 48 h. Statistical analysis was conducted with a significance level of p < 0.05. Results:The association between photobiomodulation (PBM – 660 nm) and growth factors (TGF-β3, IDP2, and IGF) modulated the viability of human dermal fibroblasts (HFF-2) in distinct ways. In MTS assays, cell viability remained similar to the control group at 24 h, with significant increases observed in the GF1:1 and GF 1:3 + PBM groups at 48 h. At 72 h, increased viability was observed in the GF1:1 and PBM + GF 1:1 groups, while PBM alone and certain combinations demonstrated reduced viability. Crystal violet assays confirmed this pattern: at 24 h, PBM alone and in combination reduced the number of adherent cells; at 48 h and 72 h, this reduction continued, particularly in PBM combinations. These findings indicate that cellular responses depend on the growth factor ratio, exposure time, and presence of light, suggesting that the interaction between PBM and growth factors is not linear and requires careful standardization for regenerative and aesthetic applications. Conclusion:The association of photobiomodulation (660 nm) with the growth factors TGF-β3, IDP2, and IGF promoted increased viability and metabolic activity of fibroblasts, as well as enhanced expression of genes related to collagen and elastin synthesis. These results indicate a synergistic effect between the therapies, with potential applications in skin rejuvenation and regenerative protocols.