Objectives:The cellular therapy using adipose-derived mesenchymal stem cells (ASCs) aims to improve tendon healing, considering that repaired tendons often result in a less resistant tissue. Our objective was to evaluate the effects of the ASCs combination with a low-level laser (LLL), an effective photobiostimulation for the healing processes. Materials and methods: Rats calcaneal tendons were divided into five groups: normal (NT), transected (T), transected and ASCs (SC) or LLL (L), or with ASCs and LLL (SCL). Results: All treated groups presented higher expression of Dcn and greater organization of collagen fibres. In comparison with T, LLL also up-regulated Gdf5 gene expression, ASCs up-regulated the expression of Tnmd, and the association of LLL and ASCs down-regulated the expression of Scx. No differences were observed for the expression of Il1b, Timp2, Tgfb1, Lox, Mmp2, Mmp8 and Mmp9, neither in the quantification of hydroxyproline, TNF-α, PCNA and in the protein level of Tnmd. A higher amount of IL-10 was detected in SC, L and SCL compared to T, and higher amount of collagen I and III was observed in SC compared to SCL. Conclusions:Transplanted ASCs migrated to the transected region, and all treatments altered the remodelling genes expression. The LLL was the most effective in the collagen reorganization, followed by its combination with ASCs. Further investigations are needed to elucidate the molecular mechanisms involved in the LLL and ASCs combination during initial phases of tendon repair.

Objectives: Burns are shown as a clinical problem for their severity and multiple complications due to the time required to heal. Therapies that improve their healing are of great importance, especially for being minimally invasive, of low cost and best performance, all related to the speed and quality of healing. This study investigated the effects of the magnetic electro stimulator Haihuá CD9 isolated or in association with Aloe vera in rats skin burns. Methods: Experimental groups (n = 30/group) were: (C) Carbopol gel; (F) A. vera/Carbopol gel; (H) Haihuá+Carbopol gel; (H+F) Haihuá+A. vera/Carbopol gel. Samples were collected on the 7th, 14th, and 21st experimental days for structural and morphometric analysis, hydroxyproline and glycosaminoglycans quantification, zymography for MMP-2 and MMP-9 and Western Blotting for TGF-β1, VEGF, Collagen I and III. Key findings: The expression of TGF-β1 in H+F was increased on the 7th day and of MMP-9 on the 7th and 14th days. The expression of VEGF increased in the first experimental periods and decreased in the last for the treated groups. There was an increase in the fibroblasts and birefringent collagen fibers in groups treated with Haihuá isolated or in association with A. vera in all periods. The quantification of collagen I increased, while collagen III decreased in H+F. The higher amount of GAGs and MMP-2 active isoform was detected in H and H+F during all periods. Conclusions: Considering the results of the present study, electromagnetic stimulation in association with the A. vera extract promoted an increase in the number of fibroblasts, GAGs content, MMP-2 activity, the deposition and organization of collagen fibers, favoring the repair of injuries to second degree burns, and may also present therapeutic potential in this injury type.

The objective of this study was to evaluate the effects of red Light Emiting Diode (red LED) irradiation on fibroblasts in adipose-derived mesenchymal stem cells (ASC) co-culture on the scratch assay. We hypothesized that red LED irradiation could stimulate paracrine secretion of ASC, contributing to the activation of genes and molecules involved in cell migration and tissue repair. ASC were co-cultured with NIH/3T3 fibroblasts through direct contact and subjected to red LED irradiation (1.45 J/cm 2 /5min6s) after the scratch assay, during 4 days. Four groups were established: fibroblasts (F), fibroblasts þ LED (FL), fibroblasts þ ASC (FC) and fibroblasts þ LED þ ASC (FLC). The analyzes were based on Ctgf and Reck expression, quantification of collagen types I and III, tenomodulin, VEGF, TGF-β1, MMP-2 and MMP-9, as well as viability analysis and cell migration. Higher Ctgf expression was observed in FC compared to F. Group FC presented higher amount of tenomodulin and VEGF in relation to the other groups. In the cell migration analysis, a higher number of cells was observed in the scratched area of the FC group on the 4 th day. There were no differences between groups considering cell viability, Reck expression, amount of collagen types I and III, MMP-2 and TGF-β1, whereas TGF-β1 was not detected in the FC group and the MMP-9 in none of the groups. Our hypothesis was not supported by the results because the red LED irradiation decreased the healing response of ASC. An inhibitory effect of the LED irradiation associated with ASC co-culture was observed with reduction of the amount of TGF-β1, VEGF and tenomodulin, possibly involved in the reduced cell migration. In turn, the ASC alone seem to have modulated fibroblast behavior by increasing Ctgf, VEGF and tenomodulin, leading to greater cell migration. In conclusion, red LED and ASC therapy can have independent effects on fibroblast wound healing, but the combination of both does not have a synergistic effect. Therefore, future studies with other parameters of red LED associated with ASC should be tested aiming clinical application for tissue repair.

Tendon injuries are common and have a high incidence of re-rupture that can cause loss of functionality. Therapies with adipose-derived stem cells (ASC) and the microcurrent (low-intensity electrical stimulation) application present promising effects on the tissue repair. We analyzed the expression of genes and the participation of some molecules potentially involved in the structural recovery of the Achilles tendon of rats, in response to the application of both therapies, isolated and combined. The tendons were distributed in five groups: normal (N), transected (T), transected and ASC (C) or microcurrent (M) or with ASC, and microcurrent (MC). Microcurrent therapy was beneficial for tendon repair, as it was observed a statistically significant increase in the organization of the collagen fibers, with involvement of the TNC, CTGF, FN, FMDO, and COL3A1 genes as well as PCNA, IL-10, and TNF-α. ASC therapy significantly increased the TNC and FMDO genes expression with no changes in the molecular organization of collagen. With the association of therapies, a significant greater collagen fibers organization was observed with involvement of the FMOD gene. The therapies did not affect the expression of COL1A1, SMAD2, SMAD3, MKX, and EGR1 genes, nor did they influence the amount of collagen I and III, caspase-3, tenomodulin (Tnmd), and hydroxyproline. In conclusion, the application of the microcurrent isolated or associated with ASC increased the organization of the collagen fibers, which can result in a greater biomechanical resistance in relation to the tendons treated only with ASC. Future studies will be needed to demonstrate the biological effects of these therapies on the functional recovery of injured tendons.

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