RESUMEN
Epidermal growth factor (EGF) and light-emitting diode (LED) are currently deployed as promissory treatments for skin repair; however, the mechanisms of their association are not yet evidenced. Thus, the present study aimed to evaluate the effects of combined treatment with EGF and red LED on the wound healing processes in rats. Adult Wistar rats were randomized in control group (CG) wounds without treatment; wounds submitted to EGF treatment (EGF); wounds submitted to LED treatment (LED); wounds submitted to EGF associated with LED treatments (EGF/LED). Treatments were performed immediately after the surgical procedure and each 24 h, totaling 8 sessions. Moreover, LED was applied before EGF treatment at a single point in the center of the wound. Morphological characteristics and the immunoexpression of COX-2, VEGF, and TGF-ß were measured. The results demonstrated that EGF/LED group presented a higher wound healing index. Additionally, all experimental groups presented similar findings in the histological evaluation, the degree of inflammation, and the area of dermis-like tissue. However, for EGF-treated animals (with or without LED), neoepithelial length was higher. Furthermore, all the treated groups decreased COX-2 and increased VEGF immunoexpression, and only EGF/LED group enhanced the TGF-ß protein expression when compared to the untreated group. This research shows that EGF and LED modulate inflammatory process and increase the vascularity. In addition, treatment of EGF associated with LED promoted a more evident positive effect for increasing TGF-ß expression and may be promising resources in the clinical treatment of cutaneous wounds.
Asunto(s)
Factor de Crecimiento Epidérmico , Factor A de Crecimiento Endotelial Vascular , Ratas , Animales , Factor de Crecimiento Epidérmico/metabolismo , Ciclooxigenasa 2 , Ratas Wistar , Cicatrización de Heridas , FototerapiaRESUMEN
The purpose of this study is to evaluate the effects of photobiomodulation (PBM) therapy in chondrocyte response by in vitro experiments and cartilage repair using an experimental model of osteoarthritis (OA) in the knee of rats. The in vitro experiment was performed with chondrocyte cells, and they were divided into two groups: non-irradiated and irradiated with PBM (808 nm; 0.8 J or 1.4 J). Then, cell proliferation was evaluated after 1, 3, and 5 days. The experimental model of osteoarthritis (OA) was performed in the knee of 64 Wistar rats, and they were assorted into control group (CG), PBM (808 nm; 1.4 J). The results of in vitro showed that PBM 1.4 J increased cell proliferation, on days 1 and 5. However, after 3 days was demonstrated a significant increase in cell proliferation in PBM 0.8 J. The in vivo experiment results demonstrated, on histological analysis, that PBM presented less intense signs of tissue degradation with an initial surface discontinuity at the superficial zone and disorganization of the chondrocytes in the cartilage region when compared to CG, after 4 and 8 weeks. These findings were confirmed by immunohistochemistry and qRT-PCR analysis which showed that PBM increased IL-4, IL-10, COL-2, Aggrecan, and TGF-ß which are anabolic factors and acts on extracellular matrix. Also, PBM reduces the IL1-ß, an inflammatory marker that operates as a catabolic factor on articular cartilage. In conclusion, these results suggest that PBM may have led to a return to tissue homeostasis, promoting chondroprotective effects and stimulating the components of the articular tissue.
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Cartílago Articular , Terapia por Luz de Baja Intensidad , Osteoartritis de la Rodilla , Osteoartritis , Animales , Cartílago Articular/patología , Condrocitos/patología , Modelos Animales de Enfermedad , Osteoartritis/genética , Osteoartritis/metabolismo , Osteoartritis/radioterapia , Osteoartritis de la Rodilla/genética , Osteoartritis de la Rodilla/radioterapia , Ratas , Ratas WistarRESUMEN
We are currently facing a pandemic that continuously causes high death rates and has negative economic and psychosocial impacts. Therefore, this period requires a quick search for viable procedures that can allow us to use safe and non-invasive clinical tools as prophylactic or even adjuvant methods in the treatment of COVID-19. Some evidence shows that photobiomodulation therapy (PBMT) can attenuate the inflammatory response and reduce respiratory disorders similar to acute lung injury (ALI), complications associated with infections, such as the one caused by the new Coronavirus (SARS-CoV-2). Hence, the aim of the present study was to evaluate the influence of PBMT (infrared low-level laser therapy) on the treatment of ALI, one of the main critical complications of COVID-19 infection, in an experimental model in rats. Twenty-four male Wistar rats were randomly allocated to three experimental groups (n = 8): control group (CG), controlled ALI (ALI), and acute lung injury and PBM (ALIP). For treatment, a laser equipment was used (808 nm; 30 mw; 1.68 J) applied at three sites (anterior region of the trachea and in the ventral regions of the thorax, bilaterally) in the period of 1 and 24 h after induction of ALI. For treatment evaluation, descriptive histopathological analysis, lung injury score, analysis of the number of inflammatory cells, and expression of interleukin 1 ß (IL-1ß) were performed. In the results, it was possible to observe that the treatment with PBMT reduced inflammatory infiltrates, thickening of the alveolar septum, and lung injury score when compared to the ALI group. In addition, PBMT showed lower immunoexpression of IL-1ß. Therefore, based on the results observed in the present study, it can be concluded that treatment with PBMT (infrared low-level laser therapy) was able to induce an adequate tissue response capable of modulating the signs of inflammatory process in ALI, one of the main complications of COVID-19.
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COVID-19 , Terapia por Luz de Baja Intensidad , Animales , COVID-19/radioterapia , Terapia por Luz de Baja Intensidad/métodos , Pulmón/patología , Masculino , Ratas , Ratas Wistar , SARS-CoV-2RESUMEN
The present study aimed to evaluate the new heterologous fibrin biopolymer associated, or not, with photobiomodulation therapy for application in tendon injuries, considered a serious and common orthopedic problem. Thus, 84 Rattus norvegicus had partial transection of the calcaneus tendon (PTCT) and were randomly divided into: control (CG); heterologous fibrin biopolymer (HFB); photobiomodulation (PBM); heterologous fibrin biopolymer + photobiomodulation (HFB + PBM). The animals received HFB immediately after PTCT, while PBM (660 nm, 40 mW, 0.23 J) started 24 h post injury and followed every 24 h for 7, 14, and 21 days. The results of the edema volume showed that after 24 h of PTCT, there was no statistical difference among the groups. After 7, 14, and 21 days, it was observed that the treatment groups were effective in reducing edema when compared to the control. The HFB had the highest edema volume reduction after 21 days of treatment. The treatment groups did not induce tissue necrosis or infections on the histopathological analysis. Tenocyte proliferation, granulation tissue, and collagen formation were observed in the PTCT area in the HFB and HFB + PBM groups, which culminated a better repair process when compared to the CG in the 3 experimental periods. Interestingly, the PBM group revealed, in histological analysis, major tendon injury after 7 days; however, in the periods of 14 and 21 days, the PBM had a better repair process compared to the CG. In the quantification of collagen, there was no statistical difference between the groups in the 3 experimental periods. The findings suggest that the HFB and PBM treatments, isolated or associated, were effective in reducing the volume of the edema, stimulating the repair process. However, the use of HFB alone was more effective in promoting the tendon repair process. Thus, the present study consolidates previous studies of tendon repair with this new HFB. Future clinical trials will be needed to validate this proposal.
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Tendón Calcáneo , Calcáneo , Terapia por Luz de Baja Intensidad , Animales , Ratas , Biopolímeros , Fibrina , Ratas WistarRESUMEN
Ultraviolet radiation (UVR) is the major etiologic agent of cutaneous photoaging, and different strategies are used to prevent and treat this condition. The polysaccharide fraction (LBPF) isolated from Lycium Barbarum fruits (goji berry) contains several active ingredients with antioxidant, immune system modulation, and antitumor effects. In addition, the photobiomodulation (PBM) is widely applied in photoaging treatment. This study investigated the effects of LBPF and PBM against the UVR-induced photodamage in the skin of hairless mice. The mice were photoaged for 6 weeks in a chronic and cumulative exposure regimen using a 300-W incandescent lamp that simulates the UVR effects. From the third to the sixth week of photoaging induction, the animals received topical applications of LBPF and PBM, singly or combined, in different orders (first LBPF and then PBM and inversely), three times per week after each session of photoaging. After completion of experiments, the dorsal region skin was collected for the analysis of thickness, collagen content, and metalloproteinases (MMP) levels. A photoprotective potential against the increase of the epithelium thickness and the fragmentation of the collagen fibers was achieved in the skin of mice treated with LBPF or PBM singly, as well as their combination. All treatments maintained the skin collagen composition, except when PBM was applied after the LBPF. However, no treatment protected against the UVR-induced MMP increase. Taken together, we have shown that the LBPF and PBM promote a photoprotective effect in hairless mice skin against epidermal thickening and low collagen density. Both strategies, singly and combined, can be used to reduce the UVR-induced cutaneous photoaging.
Asunto(s)
Colágeno/metabolismo , Medicamentos Herbarios Chinos/farmacología , Epitelio/efectos de los fármacos , Epitelio/efectos de la radiación , Terapia por Luz de Baja Intensidad , Piel/patología , Piel/efectos de la radiación , Animales , Epitelio/patología , Ratones , Ratones Pelados , Piel/efectos de los fármacos , Piel/metabolismo , Envejecimiento de la Piel/efectos de los fármacos , Envejecimiento de la Piel/patología , Envejecimiento de la Piel/efectos de la radiación , Rayos Ultravioleta/efectos adversosRESUMEN
Acne vulgaris is the most recurring skin condition in the world, causing great harm to the physical and psychological well-being of many patients. Antimicrobial photodynamic therapy (aPDT) has broad therapeutic applicability. The purpose was to evaluate in vitro the photodynamic inactivation against Propionibacterium acnes (P. acnes) biofilms by using different concentrations of hypericin (Hypericum perforatum) photosensitizer associated with different energies of low-level laser. The biofilms were placed in 96-well microplates with a 6.4-mm diameter surface, by using standard suspensions (2 × 107 CFU/mL) and grown in brain heart infusion broth (BHI) for 48 h in anaerobic chamber. Subsequently, the control group received application of 0.9% sterile saline solution for 3 min; the photosensitising groups received hypericin at concentrations of 5 and 15 µg/mL for 3 min; the laser groups received irradiation of energies of 3 and 5 J (660 nm, continuous output, 100 mW, 30 and 50 s and 100 J/cm2 and 166 J/cm2, respectively); the aPDT groups received 5 and 15 µg/mL concentrations of hypericin associated with energies of 3 and 5 J of low-level laser irradiation. After the biofilms were broken up and seeded for CFU counting. The results showed a reduction in P. acnes biofilms after aPDT emphasising that 15 µg/mL hypericin associated with 3 and 5 J laser irradiation reduced biofilms by 14.1 and 27.9%, respectively. In addition, all groups of aPDT demostrated statistically significant reductions. In vitro photodynamic inactivation against P. acnes biofilms using different concentration of hypericin photosensitizer associated with different energies of low-level laser promoted effective antimicrobial action.
Asunto(s)
Fotoquimioterapia , Acné Vulgar/tratamiento farmacológico , Antracenos , Antibacterianos/uso terapéutico , Antiinfecciosos/uso terapéutico , Biopelículas/efectos de la radiación , Humanos , Hypericum , Rayos Láser , Luz , Perileno/análogos & derivados , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/uso terapéutico , Propionibacterium acnesRESUMEN
Prolonged skin exposure to ultraviolet radiation (UVR) induces premature aging in both the epidermis and the dermis. Chronic exposure to UVR induces the activation of mitogen-activated protein kinase (MAPK) signaling pathway, activating c-Jun, c-Fos expression, and transcription factor of AP-1 activating protein. AP-1 activation results in the positive induction of matrix metalloproteinase (MMP) synthesis, which degrade skin collagen fibers. Polysaccharides from the fruit of Lycium barbarum (LBP fraction) have a range of activities and have been demonstrate to repair the photodamage. In different approaches, laser application aims to recover the aged skin without destroying the epidermis, promoting a modulation, called photobiomodulation (PBM), which leads to protein synthesis and cell proliferation, favoring tissue repair. Here we developed a topical hydrogel formulation from a polysaccharide-rich fraction of Lycium barbarum fruits (LBP). This formulation was associated with PBM (red laser) to evaluate whether the isolated and combined treatments would reduce the UVR-mediated photodamage in mice skin. Hairless mice were photoaged for 6 weeks and then treated singly or in combination with LBP and PBM. Histological, immunohistochemistry, and immunofluorescence analyses were used to investigate the levels of c-Fos, c-Jun, MMP-1, -2, and -9, collagen I, III, and FGF2. The combined regimen inhibited UVR-induced skin thickening, decreased the expression of c-Fos and c-Jun, as well as MMP-1, -2, and -9 and concomitantly increased the levels of collagen I, III, and FGF2. The PBM in combination with LBP treatment is a promising strategy for the repair of photodamaged skin, presenting potential clinical application in skin rejuvenation.
Asunto(s)
Medicamentos Herbarios Chinos/farmacología , Hidrogeles/farmacología , Terapia por Luz de Baja Intensidad , Piel/efectos de la radiación , Rayos Ultravioleta/efectos adversos , Cicatrización de Heridas/efectos de los fármacos , Cicatrización de Heridas/efectos de la radiación , Animales , Modelos Animales de Enfermedad , Femenino , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Metaloproteinasa 1 de la Matriz/metabolismo , Ratones , Ratones Pelados , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Proteínas Proto-Oncogénicas c-fos/metabolismo , Transducción de Señal , Factor de Transcripción AP-1/metabolismoRESUMEN
Skin graft is one of the most common techniques used in plastic surgery and repair. However, there are some complications that can lead to loss of the skin graft. Thus, several features have been studied with the aim of promoting the integration of skin grafts. Among these resources, the use of laser photobiomodulation (laser PBM) has been highlighted. The present study aimed to investigate the effects of laser PBM on the viability and integration of skin grafts in rats. Twenty male Wistar rats (± 250 g) were randomly assigned into two experimental groups with 10 animals each: control group, animals submitted to skin graft and simulation of laser PBM; laser PBM group, submitted to the skin graft and submitted to laser PBM at 660 nm, 40 mW, 60 s, 2.4 J. The animals were submitted to laser photobiomodulation immediately after the surgical procedure and each 24 h. Animal euthanasia occurred on the 7th day after surgery, 24 h after the last treatment session. The histopathological analysis revealed that the laser PBM showed better adhesion of the graft when compared to the control group. Likewise, the morphometric analysis of mast cells, blood vessels, and collagen showed a statistically significant increase in the animals irradiated with the laser PBM when compared to the control group. In addition, immunohistochemical analysis demonstrated that the laser PBM showed statistically higher immunoexpression of FGF when compared to the CG. However, IL-4 immunoexpression did not show statistical difference between the experimental groups. From the results obtained in the present study, it can be suggested that laser photobiomodulation was effective in promoting the integration and viability of total skin grafts in rats.
Asunto(s)
Terapia por Luz de Baja Intensidad , Trasplante de Piel , Animales , Recuento de Células , Colágeno/metabolismo , Interleucina-4/metabolismo , Masculino , Mastocitos/metabolismo , Ratas Wistar , Piel/irrigación sanguínea , Piel/patologíaRESUMEN
The aim of the present study was to evaluate the in vivo response of different wavelengths (red and near-infrared) of light-emitting diode (LED) on full-thickness skin grafts (FTSG) in rats. Thirty rats were randomly allocated into three experimental groups: control group (C); red LED treated group (R); and near-infrared LED group (NIR). Skin grafts were irradiated daily for ten consecutive days, starting immediately after the surgery using a red (630 nm) or near-infrared (850 nm) LED. The results showed that the red wavelength LED significantly enhanced the skin graft score in relation to the NIR group and increased transforming growth factor beta (TGF-ß) protein expression and density of collagen fibers compared with the other experimental groups. These results suggest that the red wavelength LED was efficient to improve the dermo-epidermal junction and modulate the expression proteins related to tissue repair.
Asunto(s)
Rayos Infrarrojos/uso terapéutico , Fototerapia/métodos , Trasplante de Piel , Animales , Colágeno/metabolismo , Epidermis/metabolismo , Epidermis/efectos de la radiación , Regulación de la Expresión Génica/efectos de la radiación , Masculino , Ratas , Factor de Crecimiento Transformador beta/metabolismo , Cicatrización de Heridas/fisiología , Cicatrización de Heridas/efectos de la radiaciónRESUMEN
OBJECTIVE: The aim of the study was to analyze bone matrix (BMX) organization after bone grafting and repair using a new bioactive glass-ceramic (Biosilicate®) associated or not with particulate autogenous bone graft. MATERIAL AND METHODS: Thirty rabbits underwent surgical bilateral parietal defects and divided into groups according to the materials used: (C) control-blood clot, (BG) particulate autogenous bone, (BS) bioactive glass-ceramic, and BG + BS. After 7, 14, and 30 days post-surgery, a fragment of each specimen was fixed in - 80 °C liquid nitrogen for zymographic evaluation, while the remaining was fixed in 10% formalin for histological birefringence analysis. RESULTS: The results of this study demonstrated that matrix organization in experimental groups was significantly improved compared to C considering collagenous organization. Zymographic analysis revealed pro-MMP-2, pro-MMP-9, and active (a)-MMP-2 in all groups, showing gradual decrease of total gelatinolytic activity during the periods. At day 7, BG presented more prominent gelatinolytic activity for pro-MMP-2 and 9 and a-MMP-2, when compared to the other groups. In addition, at day 7, a 53% activation ratio (active form/[active form + latent form]) was evident in C group, 33% in BS group, and 31% in BG group. CONCLUSION: In general, BS allowed the production of a BMX similar to BG, with organized collagen deposition and MMP-2 and MMP-9 disponibility, permitting satisfactory bone remodeling at the late period. CLINICAL RELEVANCE: The evaluation of new bone substitute, with favorable biological properties, opens the possibility for its use as a viable and efficient alternative to autologous bone graft.
Asunto(s)
Sustitutos de Huesos/farmacología , Trasplante Óseo/métodos , Cerámica/farmacología , Cráneo/cirugía , Animales , Materiales Biocompatibles/farmacología , Birrefringencia , Matriz Ósea , Regeneración Ósea/fisiología , Modelos Animales de Enfermedad , Vidrio , Masculino , Ensayo de Materiales , Conejos , Coloración y Etiquetado , Trasplante AutólogoRESUMEN
The aim of this study was to evaluate the effects of highly porous Biosilicate(®) scaffolds on bone healing in a tibial bone defect model in rats by means of histological evaluation (histopathological and immunohistochemistry analysis) of the bone callus and the systemic inflammatory response (immunoenzymatic assay). Eighty Wistar rats (12 weeks-old, weighing±300 g) were randomly divided into 2 groups (n=10 per experimental group, per time point): control group and Biosilicate® group (BG). Each group was euthanized 3, 7, 14 and 21 days post-surgery. Histological findings revealed a similar inflammatory response in both experimental groups, 3 and 7 days post-surgery. During the experimental periods (3-21 days post-surgery), it was observed that the biomaterial degradation, mainly in the periphery region, provided the development of the newly formed bone into the scaffolds. Immunohistochemistry analysis demonstrated that the Biosilicate® scaffolds stimulated cyclooxygenase-2, vascular endothelial growth factor and runt-related transcription factor 2 expression. Furthermore, in the immunoenzymatic assay, BG presented no difference in the level of tumor necrosis factor alpha in all experimental periods. Still, BG showed a higher level of interleukin 4 after 14 days post-implantation and a lower level of interleukin 10 in 21 days post-surgery. Our results demonstrated that Biosilicate® scaffolds can contribute for bone formation through a suitable architecture and by stimulating the synthesis of markers related to the bone repair.
Asunto(s)
Regeneración Ósea , Vidrio/química , Oseointegración , Fracturas de la Tibia/patología , Fracturas de la Tibia/terapia , Andamios del Tejido , Animales , Análisis de Falla de Equipo , Masculino , Ensayo de Materiales , Porosidad , Diseño de Prótesis , Ratas , Fracturas de la Tibia/fisiopatología , Resultado del TratamientoRESUMEN
This study evaluated the morphological changes produced by LLLT on the initial stages of bone healing and also studied the pathways that stimulate the expression of genes related to bone cell proliferation and differentiation. One hundred Wistar rats were divided into control and treated groups. Noncritical size bone defects were surgically created at the upper third of the tibia. Laser irradiation (Ga-Al-As laser 830 nm, 30 mW, 94 s, 2.8 J) was performed for 1, 2, 3, 5, and 7 sessions. Histopathology revealed that treated animals produced increased amount of newly formed bone at the site of the injury. Moreover, microarray analysis evidenced that LLLT produced a significant increase in the expression TGF-ß, BMP, FGF, and RUNX-2 that could stimulate osteoblast proliferation and differentiation, which may be related to improving the deposition of newly formed bone at the site of the injury. Thus, it is possible to conclude that LLLT improves bone healing by producing a significant increase in the expression of osteogenic genes.
Asunto(s)
Terapia por Luz de Baja Intensidad , Análisis de Secuencia por Matrices de Oligonucleótidos , Osteogénesis/genética , Osteogénesis/efectos de la radiación , Tibia/fisiología , Tibia/efectos de la radiación , Cicatrización de Heridas/efectos de la radiación , Animales , Regeneración Ósea/genética , Regeneración Ósea/efectos de la radiación , Masculino , Ratas , Ratas Wistar , Cicatrización de Heridas/genéticaRESUMEN
The aim of this study was to evaluate the influence of postmenopausal bone loss (induced by ovariectomy) in the process of bone healing in a tibial bone defect model in rats by means of histological evaluation of bone defects and the analysis of the expression of genes and proteins involved in bone consolidation. Twenty female Wistar rats (12 weeks old, weighing ±250 g) were randomly divided into two groups: control group (CG) and ovariectomized group (OG). Rats of OG were submitted to ovariectomy and after 8 weeks post-surgery, all animals were submitted to the tibial bone defect model. The main histological finding analysis revealed that ovariectomized animals showed a higher amount of granulation tissue and immature newly formed bone compared to CG. Furthermore, quantitative histological analysis showed that OG presented a significant decrease in the amount of newly formed bone (p = 0.0351). RT-PCR analysis showed no difference in Runx2, ALP, RANK, RANKL and Osterix gene expression 14-day post-surgery. Interestingly, immunohistochemical evaluation showed that Runx2 was down expressed (p = 0.0001) and RANKL was up expressed (p = 0.0022) in the OG. In conclusion, these data highlight that bone loss induced by ovariectomy causes an impairment in the capacity of bone to heal mainly probably because of alterations in the imbalance of osteoblasts and osteoclasts activities.
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Huesos/patología , Curación de Fractura , Tibia/fisiopatología , Fosfatasa Alcalina/metabolismo , Animales , Regeneración Ósea , Huesos/efectos de los fármacos , Subunidad alfa 1 del Factor de Unión al Sitio Principal/metabolismo , Modelos Animales de Enfermedad , Femenino , Regulación de la Expresión Génica , Inmunohistoquímica , Osteogénesis , Osteoporosis/metabolismo , Ovariectomía , Ligando RANK/metabolismo , Ratas , Ratas Wistar , Factores de Transcripción/metabolismoRESUMEN
The aim of this study was to evaluate the effects of low-level laser therapy (LLLT) on bone formation, immunoexpression of osteogenic factors, and biomechanical properties in a tibial bone defect model in rats. Sixty male Wistar rats were distributed into bone defect control group (CG) and laser irradiated group (LG). Animals were euthanized on days 15, 30, and 45 post-injury. The histological and morphometric analysis showed that the treated animals presented no inflammatory infiltrate and a better tissue organization at 15 and 30 days postsurgery. Also, a higher amount of newly formed bone was observed at 15 days postsurgery. No statistically significant difference was observed in cyclooxygenase-2 immunoexpression among the groups at 15, 30, and 45 days in the immunohistochemical analysis. Considering RUNX-2, the immunoexpression was statistically higher in the LG compared to the CG at 45 days. BMP-9 immunoexpression was significantly higher in the LG in comparison to CG at day 30. However, there was no expressivity for this immunomarker, both in the CG and LG, at the day 45 postsurgery. No statistically significant difference was observed in the receptor activator of nuclear factor kappa-B ligand immunoexpression among the groups in all periods evaluated. No statistically significant difference among the groups was observed in the maximal load in any period of time. Our findings indicate that laser therapy improved bone healing by accelerating the development of newly formed bone and activating the osteogenic factors on tibial defects, but the biomechanical properties in LG were not improved.
Asunto(s)
Curación de Fractura/efectos de la radiación , Terapia por Luz de Baja Intensidad , Osteogénesis/efectos de la radiación , Animales , Fenómenos Biomecánicos , Regeneración Ósea/fisiología , Regeneración Ósea/efectos de la radiación , Subunidad alfa 1 del Factor de Unión al Sitio Principal/metabolismo , Ciclooxigenasa 2/metabolismo , Curación de Fractura/fisiología , Factor 2 de Diferenciación de Crecimiento/metabolismo , Inmunohistoquímica , Láseres de Semiconductores/uso terapéutico , Masculino , Osteoblastos/metabolismo , Osteoblastos/patología , Osteoblastos/efectos de la radiación , Osteogénesis/fisiología , Ligando RANK/metabolismo , Ratas , Ratas Wistar , Fracturas de la Tibia/patología , Fracturas de la Tibia/fisiopatología , Fracturas de la Tibia/radioterapia , Factores de TiempoRESUMEN
The aim of this study was to analyze the effects of low-level laser therapy (LLLT) on the prevention of cartilage damage after the anterior cruciate ligament transection (ACLT) in knees of rats. Thirty male rats (Wistar) were distributed into three groups (n = 10 each): injured control group (CG); injured laser-treated group at 10 J/cm(2) (L10), and injured laser-treated group at 50 J/cm(2) (L50). Laser treatment started immediately after the surgery and it was performed for 15 sessions. An 808 nm laser, at 10 and 50 J/cm(2), was used. To evaluate the effects of LLLT, the qualitative and semi-quantitative histological, morphometric, and immunohistochemistry analysis were performed. Initial signs of tissue degradation were observed in CG. Interestingly, laser-treated animals presented a better tissue organization, especially at the fluence of 10 J/cm(2). Furthermore, laser phototherapy was able of modulating some of the aspects related to the degenerative process, such as the prevention of proteoglycans loss and the increase in cartilage area. However, LLLT was not able of modulating chondrocytes proliferation and the immunoexpression of markers related to inflammatory process (IL-1 and MMP-13). This study showed that 808 nm laser, at both fluences, prevented features related to the articular degenerative process in the knees of rats after ACLT.
Asunto(s)
Lesiones del Ligamento Cruzado Anterior , Ligamento Cruzado Anterior/patología , Terapia por Luz de Baja Intensidad , Animales , Modelos Animales de Enfermedad , Inmunohistoquímica , Interleucina-1beta/metabolismo , Masculino , Metaloproteinasa 13 de la Matriz/metabolismo , Ratas WistarRESUMEN
PURPOSE: The aim of this work was to analyze the effect of fibrin biopolymer sealant (FS) associated or not to aquatic exercise (AE) on the calcaneal tendon repair. METHODS: Forty-four female Wistar rats were randomly divided into four experimental groups: Lesion control (L), Lesion and FS (LS), Lesion and AE (LE) and Lesion and FS associated to AE (LSE). The edema volume (EV), collagen ratio, and histopathological analysis were evaluated after 7, 14, and 21 days of partial tendon transection. RESULTS: The EV was statistically reduced for all treatment groups after 7 and 21 days when compared to L group. The LS and LSE had the highest EV reduction after 21 days of treatment. The FS group didn't induce tissue necrosis or infections on the histopathological analysis. It was observed tenocytes proliferation, granulation tissue and collagen formation in the tendon partial transection area in the FS group. The LSE demonstrated higher amount of granulation tissue and increased the collagen deposition at the injury site. CONCLUSIONS: Our data suggests that the therapeutic potential of the association of heterologous fibrin biopolymer sealant with aquatic exercise program should be further explored as it may stimulate the regeneration phase and optimize calcaneal tendon recovery.
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Tendón Calcáneo , Procedimientos de Cirugía Plástica , Tendón Calcáneo/cirugía , Animales , Colágeno , Femenino , Adhesivo de Tejido de Fibrina , Ratas , Ratas WistarRESUMEN
The engineering of multifunctional surgical bactericidal nanofibers with inherent suitable mechanical and biological properties, through facile and cheap fabrication technology, is a great challenge. Moreover, hernia, which is when organ is pushed through an opening in the muscle or adjacent tissue due to damage of tissue structure or function, is a dire clinical challenge that currently needs surgery for recovery. Nevertheless, post-surgical hernia complications, like infection, fibrosis, tissue adhesions, scaffold rejection, inflammation, and recurrence still remain important clinical problems. Herein, through an integrated electrospinning, plasma treatment and direct surface modification strategy, multifunctional bactericidal nanofibers were engineered showing optimal properties for hernia repair. The nanofibers displayed good bactericidal activity, low inflammatory response, good biodegradation, as well as optimal collagen-, stress fiber- and blood vessel formation and associated tissue ingrowth in vivo. The disclosed engineering strategy serves as a prominent platform for the design of other multifunctional materials for various biomedical challenges.
Asunto(s)
Antibacterianos/farmacología , Materiales Biocompatibles , Gelatina/farmacología , Hernia Abdominal/cirugía , Herniorrafia/instrumentación , Metacrilatos/farmacología , Nanofibras , Poliésteres/farmacología , Infección de la Herida Quirúrgica/prevención & control , Andamios del Tejido , Animales , Antibacterianos/química , Modelos Animales de Enfermedad , Gelatina/química , Hernia Abdominal/patología , Metacrilatos/química , Ratones , Células 3T3 NIH , Nanomedicina , Poliésteres/química , Ratas , Infección de la Herida Quirúrgica/microbiología , Cicatrización de Heridas/efectos de los fármacosRESUMEN
OBJECTIVE: The present study aimed to evaluate the effectiveness of photobiomodulation therapy by light-emitting diode on osteoarthritis treatment in the knees of rats. DESIGN: Twenty male Wistar rats were randomly assigned into two experimental groups: OAC: animals subjected to induction of osteoarthritis, without therapeutic intervention and the group OAL: animals subjected to induction of osteoarthritis treated with light-emitting diode photobiomodulation therapy (850 nm, 200 mW, 6 J). RESULTS: The results of gait analysis showed no statistical difference between the groups. The histological findings showed that the OAL group presented abnormal chondrocyte orientation, yet with less irregularities along fibrillation and the joint tissue. Thus, it presented a lower degenerative process when evaluated by the Osteoarthritis Research Society International. Likewise, in the immunohistochemical analysis, the OAL group showed higher collagen 2 and transforming growth factor ß immunoexpression when compared with the OAC group. CONCLUSIONS: Given the above, it is possible to suggest that the photobiomodulation therapy by light-emitting diode had positive effects on the expression of extracellular matrix proteins responsible for synthesis of articular tissue.
Asunto(s)
Terapia por Luz de Baja Intensidad , Osteoartritis de la Rodilla/terapia , Animales , Condrocitos/patología , Colágeno Tipo II/metabolismo , Modelos Animales de Enfermedad , Análisis de la Marcha , Inmunohistoquímica , Osteoartritis de la Rodilla/patología , Ratas Wistar , Rodilla de Cuadrúpedos/metabolismo , Rodilla de Cuadrúpedos/patología , Factor de Crecimiento Transformador beta/metabolismoRESUMEN
Objective: Technological advances have provided new alternatives to the analysis of skin flap viability in animal models; however, the interrater validity and reliability of these techniques have yet to be analyzed. The present study aimed to evaluate the interrater validity and reliability of three different methods: weight of paper template (WPT), paper template area (PTA), and photographic analysis. Approach: Sixteen male Wistar rats had their cranially based dorsal skin flap elevated. On the seventh postoperative day, the viable tissue area and the necrotic area of the skin flap were recorded using the paper template method and photo image. The evaluation of the percentage of viable tissue was performed using three methods, simultaneously and independently by two raters. The analysis of interrater reliability and viability was performed using the intraclass correlation coefficient and Bland Altman Plot Analysis was used to visualize the presence or absence of systematic bias in the evaluations of data validity. Results: The results showed that interrater reliability for WPT, measurement of PTA, and photographic analysis were 0.995, 0.990, and 0.982, respectively. For data validity, a correlation >0.90 was observed for all comparisons made between the three methods. In addition, Bland Altman Plot Analysis showed agreement between the comparisons of the methods and the presence of systematic bias was not observed. Innovation: Digital methods are an excellent choice for assessing skin flap viability; moreover, they make data use and storage easier. Conclusion: Independently from the method used, the interrater reliability and validity proved to be excellent for the analysis of skin flaps' viability.
RESUMEN
Herein, we report the design of electrospun ultrathin fibers based on the combination of three different polymers polycaprolactone (PCL), polyethylene glycol (PEG), and gelatin methacryloyl (GelMA), and their potential bactericidal activity against three different bacteria Staphylococcus aureus (S. aureus), Pseudomonas aeruginosa (P. aeruginosa), and Methicillin-resistant Staphylococcus aureus (MRSA). We evaluated the morphology, chemical structure and wettability before and after UV photocrosslinking of the produced scaffolds. Results showed that the developed scaffolds presented hydrophilic properties after PEG and GelMA incorporation. Moreover, they were able to significantly reduce gram-positive, negative, and MRSA bacteria mainly after UV photocrosslinking (PCL:PEG:GelMa-UV). Furthermore, we performed a series of study for gaining a better mechanistic understanding of the scaffolds bactericidal activity through protein adsorption study and analysis of the reactive oxygen species (ROS) levels. Furthermore, the in vivo subcutaneous implantation performed in rats confirmed the biocompatibility of our designed scaffolds.