Efeitos da fotobiomodulação associada a terapia de células-tronco mesenquimais derivadas de tecido adiposo e implantadas em joelhos com osteoartrite experimental

Abstract

Osteoarthritis (OA) is a chronic degenerative process characterized by progressive deterioration of the cartilagereaching subchondral bone. Current interventions have little or no effect on the repair of articular cartilage. Therefore, the therapy throughmesenchymal stem cells (MSC’s) has been a target of interest due to its multilineage potential, becoming an important tool in the attempt of tissue repair. The photobiomodulation (PBMT) has been shown to be favorable in the proliferation of various cell types, including MSC’s. The aim of this study is to determine whether PBMT can increase the retention of adipocyte-derived stem cells (ADSC's) injected into the knee of the rat submitted to the experimental model of osteoarthritis and to analyze the chondroprotective effects of these therapies. ADSC's were collected from 3 male Fischer-344 rats and validated by flow cytometry. The sample was composed of 50 Fischer-344 rats and distributed into five groups: Control group (healthy animals), OA group (animals with OA), OA PBMT group (OA animals treated with PBMT therapy), OA ADSCs group (OA treated with ADSC's injection), and OA ADSC's PBMT group (animals with OA treated with ADSC's injection and PBMT). OA was induced by intra-articular injection of 4% papain solution. OA ADSC's and OA ADSC's PBMT animals received intra-articular injection of ADSC's (1x10⁶) diluted in 100μ of culture medium. For the groups that received PBMT (parameters used: wavelength of 808nm, power of 50mW, energy of 2J, density of energy 71.2J/cm² and spot size 0,028cm²) the applications were performed in 4 points of the articular line of the knee on consecutive days. The euthanasia was performed on the 3rd and 7th days after the treatments,which the articular cartilage was extracted for the quantification of the gene expression by RT/ PCR of SRY, IL-1β, IL-6, TNF-α, IL- MMP-1, MMP's 1 and 2, TIMP's 1 and 2 and collagen type II.For the statistical analysis, One way ANOVA with Tukey's post-hoc test was used andall data are expressed as mean±standard deviation with P<0,05. The results showed that the PBMT and ADSC’s therapies decreased the expression of pro-inflammatory cytokines (IL-1β, IL-6 and TNF-α) and MMP’s 1 and 2 when compared to the OA group. In addition, they increased the gene expression of TIMP's 1 and 2, IL-10 and Collagen type II. And the effects are more effective when therapies are associated. PBMT stimulated the retention of these cells in the intra-articular space. We conclude that the intra-articular ADSC’s injection associated with PBMT has chondroprotective action, modulating the inflammatory process and decreasing the cytokines and MMP's.