Desenvolvimento de scaffolds a partir de compostos bioativos extraídos de esponjas marinhas para uso na engenharia do tecido ósseo
Data
2021-02-24
Autores
Silva, Jonas de Araújo 
Orientadores
Granito, Renata Neves
Tipo
Dissertação de mestrado
Título da Revista
ISSN da Revista
Título de Volume
Resumo
O campo da engenharia de tecidos está constantemente em busca por novos biomateriais, visando atender a demanda global por tratamentos inovadores na medicina regenerativa. A tecnologia relacionada ao desenvolvimento desses biomateriais está atualmente associada às matérias-primas, técnicas e equipamentos de origem estrangeira, o que eleva os preços e, consequentemente, limita o seu uso, principalmente no sistema público de saúde. Economicamente mais viáveis, os biomateriais de origem natural são ainda considerados mais biocompatíveis que os similares de origem sintética, por possuírem uma superfície biointerativa, para adesão e proliferação celular, além da vantajosa possibilidade de aproveitamento sustentável da rica e inexplorada biodiversidade brasileira. Dentro deste contexto, esta dissertação é composta por dois capítulos. O primeiro objetivou revisar sistematicamente a literatura científica relacionada aos scaffolds (matrizes porosas tridimensionais) derivados das esponjas marinhas para aplicação na engenharia do tecido ósseo. Foram encontrados 8 artigos que atenderam aos critérios de inclusão, sendo que a análise qualitativa conjunta dos resultados desses estudos demonstrou o potencial dos scaffolds naturais, uma vez que permitiram a adesão, a proliferação e a diferenciação celular. Com esses resultados promissores, o segundo capítulo dessa dissertação visou aproveitar o potencial da biodiversidade marinha brasileira para a obtenção de matérias-primas para o desenvolvimento de scaffolds para uso como enxerto ósseo. Sendo assim, dois compostos bioativos foram extraídos das esponjas marinhas: a biosílica, oriunda da esponja Dragmacidon reticulatum e a espongina, proveniente da esponja Aplysina fulva. Na sequência, scaffolds híbridos foram elaborados a partir de duas proporções desses biomateriais, 70:30 e 50:50 de natureza orgânica (espongina) e inorgânica (biosílica) com a incorporação em sua estrutura de agente porogênico (microesferas de Na2HPO4) planejado para ter degradação controlada uma vez implantado. Estes scaffolds foram avaliados quanto às suas características estruturais, propriedades físico-químicas e resposta biológica in vitro, comparando-os aos scaffolds produzidos a partir de sílica disponível comercialmente. A análise de microscopia eletrônica de varredura (MEV) demonstrou a dissolução das microesferas do agente porogênico após 1 dia de incubação em fluído corporal simulado (SBF) e a degradação gradual da matéria orgânica ao longo do período de 21 dias de incubação. Além disso, a quantificação elementar por espectroscopia de energia dispersiva (EDS) evidenciou a diminuição da quantidade relativa de íons de sódio e fósforo com o aumento da concentração de íons de cálcio e cloro adsorvidos aos scaffolds. A caracterização dos scaffolds incluiu ainda a sua análise por raios-X de difração (XRD), que demonstrou a presença de cristais de NaCl em todos os grupos de scaffolds após incubação. Posteriormente, os scaffolds foram incubados em solução tampão fosfato-salino (PBS) e a avaliação do pH da solução demonstrou caráter mais alcalino dos grupos contendo biosílica quando comparados aos grupos com sílica comercial e ao controle. Já a degradação da massa demonstrou que mais de 50% dos scaffolds foram degradados após o primeiro dia de incubação. O ensaio de de AlamarBlue® com células da linhagem osteogênica demostrou que somente os scaffolds de sílica comercial 70:30 apresentaram citotoxicidade após 1 dia de incubação em concentração de 0.01g/ml. Conjuntamente, os resultados obtidos demonstram que estes scaffolds desenvolvidos a partir de compostos bioativos extraídos de esponjas marinhas possuem propriedades físico-químicas adequadas para emprego em terapias regenerativas relacionadas ao tecido ósseo. A proposta futura inclui ensaios biológicos para elucidar o potencial osteogênico e o dinamismo biológico desses scaffolds após implantação in vivo, que serão importantes para a seleção dos biomateriais com melhor desempenho, em termos de durabilidade, integração tecidual e resposta biológica.
The field of tissue engineering is constantly searching for new biomaterials due to the global demand for innovative treatments for regenerative medicine. The technology related to these biotechnological materials is currently associated with raw materials, techniques and equipment of foreign origins, which raises the price of the biomaterials and, consequently, limits their clinical use, especially in the public health system. Economically more affordable, natural biomaterials are considered more biocompatible than similar synthetic ones, because they have a bio-interactive surface for cell adhesion and proliferation, in addition to the advantageous possibility of sustainable use of the rich and unexplored Brazilian biodiversity. In this context, this dissertation is composed by two chapters. The first chapter aimed to systematically review the scientific literature related to scaffolds (tridimensional porous matrices) developed from compounds derived from marine sponges for bone tissue engineering application. A total of 8 studies were found matching the inclusions criteria previously stablished, being that the qualitative synthesis was performed on these studies and the results demonstrated the potential of incorporating marine sponge derived biomaterials into scaffolds, once it encouraged cells adhesion and proliferation, compared to similar synthetic products. With those promising results, the second chapter of this dissertation aimed to harness the potential of Brazilian marine biodiversity to obtain raw materials that were used in the development of scaffolds for use as bone graft. Therefore, two bioactive compounds were extracted from marine sponges: biosilica, a biomaterial found in the body of the marine sponge Dragmacidon reticulation and spongin, a compound extracted from the marine sponge Aplysina fulva. Hybrid scaffolds were elaborated from 2 different proportions of those biomaterials, 70:30 and 50:50 of organic (spongin) and inorganic (biosilica) nature, to evaluate their physical-chemical and biological properties, comparing its performance with scaffolds made from commercially available silica. In this manner, the scanning electron microscopy (SEM) showed the complete dissolution of the porogenic agent after one day of incubation and the gradual organic matter degradation throughout 21 days of incubation. In addition, the elemental quantification by dispersive energy spectroscopy (EDS) showed decreasing relative amount of sodium and phosphorus ions with increasing concentration of calcium and chlorine ions adsorbed on the scaffolds surface. The characterization of scaffolds also included their X-ray diffraction analysis (XRD), that demonstrated the presence of NaCl crystals in all the scaffolds after 1, 7 e 21 days of incubation. After that, scaffolds were incubated in phosphate buffered saline (PBS) and the pH evaluation of the solution showed predominantly more alkaline like character from biosilic containing groups when compared to the commercial silica and control groups. The degradation of the mass demonstrated that more than 50% of scaffolds were degraded after the first day of incubation. The AlamarBlue® showed that the scaffolds of commercial silica 70:30 presented cytotoxicity after 1 day incubation. Together, those results demonstrate that these scaffolds developed from bioactive compounds extracted from marine sponges have structural and physical-chemical properties suitable for use in regenerative therapies related to bone tissue The future proposal includes the biological assays, in progress, that will present relevant parameters on the osteogenic potential and biological dynamism of these scaffolds after implantation in surgically created defects in animal bones, important for the selection of biomaterials with better performance, in terms of durability, tissue integration and biological response important for the selection of biomaterials with the best performance, in terms of durability, tissue integration and biological response.
The field of tissue engineering is constantly searching for new biomaterials due to the global demand for innovative treatments for regenerative medicine. The technology related to these biotechnological materials is currently associated with raw materials, techniques and equipment of foreign origins, which raises the price of the biomaterials and, consequently, limits their clinical use, especially in the public health system. Economically more affordable, natural biomaterials are considered more biocompatible than similar synthetic ones, because they have a bio-interactive surface for cell adhesion and proliferation, in addition to the advantageous possibility of sustainable use of the rich and unexplored Brazilian biodiversity. In this context, this dissertation is composed by two chapters. The first chapter aimed to systematically review the scientific literature related to scaffolds (tridimensional porous matrices) developed from compounds derived from marine sponges for bone tissue engineering application. A total of 8 studies were found matching the inclusions criteria previously stablished, being that the qualitative synthesis was performed on these studies and the results demonstrated the potential of incorporating marine sponge derived biomaterials into scaffolds, once it encouraged cells adhesion and proliferation, compared to similar synthetic products. With those promising results, the second chapter of this dissertation aimed to harness the potential of Brazilian marine biodiversity to obtain raw materials that were used in the development of scaffolds for use as bone graft. Therefore, two bioactive compounds were extracted from marine sponges: biosilica, a biomaterial found in the body of the marine sponge Dragmacidon reticulation and spongin, a compound extracted from the marine sponge Aplysina fulva. Hybrid scaffolds were elaborated from 2 different proportions of those biomaterials, 70:30 and 50:50 of organic (spongin) and inorganic (biosilica) nature, to evaluate their physical-chemical and biological properties, comparing its performance with scaffolds made from commercially available silica. In this manner, the scanning electron microscopy (SEM) showed the complete dissolution of the porogenic agent after one day of incubation and the gradual organic matter degradation throughout 21 days of incubation. In addition, the elemental quantification by dispersive energy spectroscopy (EDS) showed decreasing relative amount of sodium and phosphorus ions with increasing concentration of calcium and chlorine ions adsorbed on the scaffolds surface. The characterization of scaffolds also included their X-ray diffraction analysis (XRD), that demonstrated the presence of NaCl crystals in all the scaffolds after 1, 7 e 21 days of incubation. After that, scaffolds were incubated in phosphate buffered saline (PBS) and the pH evaluation of the solution showed predominantly more alkaline like character from biosilic containing groups when compared to the commercial silica and control groups. The degradation of the mass demonstrated that more than 50% of scaffolds were degraded after the first day of incubation. The AlamarBlue® showed that the scaffolds of commercial silica 70:30 presented cytotoxicity after 1 day incubation. Together, those results demonstrate that these scaffolds developed from bioactive compounds extracted from marine sponges have structural and physical-chemical properties suitable for use in regenerative therapies related to bone tissue The future proposal includes the biological assays, in progress, that will present relevant parameters on the osteogenic potential and biological dynamism of these scaffolds after implantation in surgically created defects in animal bones, important for the selection of biomaterials with better performance, in terms of durability, tissue integration and biological response important for the selection of biomaterials with the best performance, in terms of durability, tissue integration and biological response.
Descrição
Citação
SILVA, Jonas de Araújo. Desenvolvimento de scaffolds a partir de compostos bioativos extraídos de esponjas marinhas para uso na engenharia do tecido ósseo. 2021. 83f. Dissertação (Mestrado em Bioprodutos e Bioprocessos) - Instituto de Saúde e Sociedade, Universidade Federal de São Paulo, Santos, 2021.