Efeitos de curativo de colágeno de esponja marinha associado ou não à fotobiomodulação no reparo cutâneo de ratos
Data
2022-07-29
Autores
Sales, Abdias Fernando Simon 
Orientadores
Renno, Ana Claudia Muniz
Tipo
Dissertação de mestrado
Título da Revista
ISSN da Revista
Título de Volume
Resumo
Introdução: Lesões cutâneas representam um grave problema de saúde mundial. A literatura científica indica os curativos de colágeno marinho como promissoras terapêuticas nesse cenário e apresenta a fotobiomodulação (FBM) como um recurso já consolidado na estimulação do reparo tecidual. A hipótese desse trabalho foi de que o curativo de colágeno de esponja marinha apresentaria características físicas adequadas, e que sua associação com a FBM potencializaria o processo de reparo cutâneo. Objetivo: Caracterizar e avaliar os efeitos biológicos de curativo de colágeno de esponja marinha associado ou não à FBM no processo de reparo tecidual em modelo de lesão cutânea de ratos. Material e Métodos: A análise da morfologia do curativo foi realizada por meio de microscopia eletrônica de varredura (MEV) e o ensaio de tração foi utilizado para a mensuração de sua resistência mecânica. Para avaliação dos efeitos biológicos, lesões cutâneas foram realizadas cirurgicamente em 18 ratos, os quais foram divididos igualmente e aleatoriamente em 3 grupos experimentais (n=6): grupo controle (GC): animais com lesão cutânea mas sem tratamento; grupo curativo cutâneo (GCC): animais com lesão cutânea tratados com curativo cutâneo; e o grupo curativo + FBM (GCL): animais com lesão cutânea que receberam 7 sessões de irradiação de laser vermelho (1 J por ponto), em 4 pontos adjacentes ao curativo implantado no local da lesão. Após período experimental de 7 dias os animais foram eutanasiados por overdose anestésica e amostras teciduais do local da lesão foram coletadas e processadas para a realização das avaliações
histomorfológicas, histomorfométricas e imunoistoquímica, tanto qualitativas quanto semiquantitativas de COX2, TGFβ, FGF e VEGF. Resultados: O MEV demonstrou que os curativos cutâneos apresentaram poros e fibras interconectas ao longo da estrutura, e adequada resistência mecânica foi observada. Na análise de histomorfologia foi observado que todos os grupos experimentais apresentaram uma incompleta reepitelização, presença de tecido de granulação com infiltrado inflamatório e vasos sanguíneos no local da lesão. Além disso, foram identificados granulomas tipo corpo estranho no GCC e no GCL. Nas histomorfometrias de comprimento da neoepiderme e da ferida, e a área de tecido de granulação não foram identificadas diferenças estatísticas entre os grupos. A imunomarcação de COX2, TGFβ, FGF e VEGF foi observada predominantemente na área da lesão de todos os grupos experimentais, tendo sido identificada uma diferença estatisticamente significativa no score de imunomarcação de FGF do GCL em relação ao GC. Conclusão: O curativo avaliado apresentou características físicas adequadas e sua associação com FBM apresentou efeitos biológicos favoráveis ao processo de reparo cutâneo. Diante desses achados, pode-se concluir que o tratamento associado pode ser considerado como conduta terapêutica promissora à estimulação do reparo cutâneo. No entanto, estudos com períodos experimentais mais longos devem ser realizados para o fornecimento de informações sobre as fases tardias do processo de reparo cutâneo.
Introduction: Skin wounds represent a global health problem. The scientific literature indicates marine collagen dressings as promising therapies in this scenario and presents photobiomodulation therapy (PBMT) as an already consolidated resource in the stimulation of tissue repair. The hypothesis of this study was that the marine sponge collagen dressing would present adequate physical characteristics for application in regenerative medicine, and that its association with PBMT would improve the skin repair process. Objective: The present study aims to characterize and evaluate the biological effects of a marine sponge collagen dressing associated or not with PBMT on the tissue repair process in an experimental model of skin wounds. Material and Methods: The morphology of the dressing was performed by scanning electron microscopy (MEV) and a tensile assay was used to measure its mechanical strength. In order to evaluate its biological effects, cutaneous wounds were surgically developed in 18 rats, which were divided equally and randomly into 3 experimental groups: control group (GC): animals with skin wounds but without treatment; marine sponge collagen cutaneous dressing group (GCC): animals with skin wounds treated with skin dressing; and the dressing group + PBMT (GCL): animals with skin wounds who received 7 sessions of red laser irradiation (1 J per point) at 4 points adjacent to the dressing implanted at the wound site. After a 7-day experimental period, the animals were euthanized by anesthetic overdose, and tissue samples from the wound’s site were collected and processed for the performance of histomorphological, histomorphometric and immunohistochemical evaluations, both qualitative and semiquantitative of immunostaining of COX2, TGFβ, FGF and VEGF. Results: The skin dressing presented pores formed by interconnected fibers along its structure, and adequate mechanical strength was observed. In histomorphology, incomplete re-epithelialization and the presence of granulation tissue with inflammatory infiltrate were observed at the wound’s site in all experimental groups. In addition, foreign body-like granulomas were identified in the GCC and GCL. The immunostaining of COX2, TGFβ, FGF and VEGF was observed predominantly in the wound area of all experimental groups, and a statistically significant difference was identified in the FGF immunostaining score of the GCL in relation to the GC. Conclusion: The evaluated dressing presented adequate physical characteristics and its association with PBMT presented favorable biological effects to the skin repair process. Based on these findings, it can be concluded that the associated treatment can be considered as a promising therapeutic approach to stimulation of skin repair. However, studies with longer experimental periods should be performed to provide information of the late stages of the skin repair process.
Introduction: Skin wounds represent a global health problem. The scientific literature indicates marine collagen dressings as promising therapies in this scenario and presents photobiomodulation therapy (PBMT) as an already consolidated resource in the stimulation of tissue repair. The hypothesis of this study was that the marine sponge collagen dressing would present adequate physical characteristics for application in regenerative medicine, and that its association with PBMT would improve the skin repair process. Objective: The present study aims to characterize and evaluate the biological effects of a marine sponge collagen dressing associated or not with PBMT on the tissue repair process in an experimental model of skin wounds. Material and Methods: The morphology of the dressing was performed by scanning electron microscopy (MEV) and a tensile assay was used to measure its mechanical strength. In order to evaluate its biological effects, cutaneous wounds were surgically developed in 18 rats, which were divided equally and randomly into 3 experimental groups: control group (GC): animals with skin wounds but without treatment; marine sponge collagen cutaneous dressing group (GCC): animals with skin wounds treated with skin dressing; and the dressing group + PBMT (GCL): animals with skin wounds who received 7 sessions of red laser irradiation (1 J per point) at 4 points adjacent to the dressing implanted at the wound site. After a 7-day experimental period, the animals were euthanized by anesthetic overdose, and tissue samples from the wound’s site were collected and processed for the performance of histomorphological, histomorphometric and immunohistochemical evaluations, both qualitative and semiquantitative of immunostaining of COX2, TGFβ, FGF and VEGF. Results: The skin dressing presented pores formed by interconnected fibers along its structure, and adequate mechanical strength was observed. In histomorphology, incomplete re-epithelialization and the presence of granulation tissue with inflammatory infiltrate were observed at the wound’s site in all experimental groups. In addition, foreign body-like granulomas were identified in the GCC and GCL. The immunostaining of COX2, TGFβ, FGF and VEGF was observed predominantly in the wound area of all experimental groups, and a statistically significant difference was identified in the FGF immunostaining score of the GCL in relation to the GC. Conclusion: The evaluated dressing presented adequate physical characteristics and its association with PBMT presented favorable biological effects to the skin repair process. Based on these findings, it can be concluded that the associated treatment can be considered as a promising therapeutic approach to stimulation of skin repair. However, studies with longer experimental periods should be performed to provide information of the late stages of the skin repair process.
Descrição
Citação
SALES, Abdias Fernando Simon. Efeitos de curativo de colágeno de esponja marinha associado ou não à fotobiomodulação no reparo cutâneo de ratos. 2022. 92 f. Dissertação (Mestrado em Bioprodutos e Bioprocessos) - Instituto de Saúde e Sociedade, Universidade Federal de São Paulo, Santos, 2022.