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Previous issue date: 2014-01-15 / In recent decades, tissue engineering techniques have been reported in the literature as an alternative to conventional autogenous grafts for bone defects and subsequent installation of dental implants, combining a material with the same biological properties of autogenous bone without its limiting factors. This technology requires a carrier for the cells, where hyaluronic acid, a natural glycosaminoglycan, appears to have suitable characteristics to carry out this role. It exerts various biological functions depending on its molecular weight, which can be classified as high (> 1000 kDa), low (from 50 to 1000 kDa) or very low (<50 kDa). Furthermore, there is the hyaluronidase, an enzyme that degrades hyaluronic acid into smaller fragments, influencing the cellular response. Thus, this study aimed to evaluate in vitro the influence of the enzyme hyaluronidase (HYAL) on the high hyaluronic acid (HA-HMW) and low molecular weight (HA-LMW) and their potential cytotoxicity on NIH - 3T3 cells. The MTT assay was performed analyzing cell viability of the following groups: (G1) Cells + HA-HMW; (G2) Cells + HA- LMW; (G3) Cells + HA-HMW + HYAL; (G4) Cells + HA-LMW + HYAL; (G5) Cells + HA-HMW + hydroxyapatite; (G6) Cells + HA-LMW + hydroxyapatite; (G7) Cells + HA-HMW + HYAL + hydroxyapatite; (G8) Cells + HA-LMW + HYAL + hydroxyapatite; (G9) Cells (positive control); (G10) Cells + hypochlorite (negative control). The cell viability for each group were as follows: (G1) 76,0%, (G2) 63,3%, (G3) 67,4%, (G4) 76,5%, (G5) 57,6%, (G6) 60,8%, (G7) 64,4%, (G8) 74,3%, (G9) 100% e (G10) 12,4%. It was found that all groups had significantly higher cell viability compared to the negative control. And although there was no significant difference between experimental groups, only the G1, G4 and G8 groups did not differ significantly from the positive control. Therefore, HA-HMW had better viability in the absence of enzyme hyaluronidase, although HA-LMW provided greater cell viability in the presence of the enzyme. Results indicated that the low-weight hyaluronic acid might be applicable for tissue engineering grafting techniques. / Nas ?ltimas d?cadas, t?cnicas envolvendo engenharia tecidual t?m sido reportadas na literatura como op??o alternativa aos enxertos aut?genos convencionais para corre??o de defeitos ?sseos e posterior instala??o de implantes dent?rios. Estas buscam basicamente um material que apresente as mesmas propriedades biol?gicas do osso aut?geno sem seus fatores limitantes. Tal tecnologia necessita, entre outros componentes, de um scaffold para as c?lulas, onde o ?cido hialur?nico, um glicosaminoglicano natural, parece ter caracter?sticas adequadas para exercer este papel. Ele exerce fun??es biol?gicas diferentes dependendo do seu peso molecular, que pode ser classificado em alto (> 1000 kDa), baixo (de 50 a 1000 kDa) ou baix?ssimo (< 50 kDa). Al?m disso, no organismo humano h? a presen?a da hialuronidase, enzima que degrada o ?cido hialur?nico em fragmentos menores, elementos estes que possivelmente podem influenciar a resposta celular. Desta forma, este estudo buscou avaliar, in vitro, a influ?ncia da enzima hialuronidase (HIAL) sobre o ?cido hialur?nico de alto (AH-APM) e baixo peso molecular (AH-BPM), bem como seu poss?vel potencial citot?xico sobre c?lulas da linhagem NIH-3T3. Para tal, foi realizado o teste de MTT analisando a viabilidade celular dos seguintes grupos: (G1) C?lulas + AH-APM; (G2) C?lulas + AH-BPM; (G3) C?lulas + AH-APM + HIAL; (G4) C?lulas + AH-BPM + HIAL; (G5) C?lulas + AH-APM + Hidroxiapatita; (G6) C?lulas + AH-BPM + Hidroxiapatita; (G7) C?lulas + AH-APM + HIAL + Hidroxiapatita; (G8) C?lulas + AH-BPM + HIAL + Hidroxiapatita; (G9) C?lulas (controle positivo); (G10) C?lulas + hipoclorito (controle negativo). A viabilidade celular m?dia de cada grupo foi: (G1) 76,0%, (G2) 63,3%, (G3) 67,4%, (G4) 76,5%, (G5) 57,6%, (G6) 60,8%, (G7) 64,4%, (G8) 74,3%, (G9) 100% e (G10) 12,4%. Os resultados indicaram que todos os grupos apresentaram viabilidade celular significativamente superior ao controle negativo. E apesar de n?o haver diferen?a significativa entre os grupos experimentais, somente os grupos G1, G4 e G8 n?o diferiram do controle positivo. O AH-APM apresentou melhor viabilidade na aus?ncia da enzima hialuronidase, enquanto que o AH-BPM proporciona uma melhor viabilidade celular na presen?a desta enzima.
| Identifer | oai:union.ndltd.org:IBICT/oai:tede2.pucrs.br:tede/1237 |
| Date | 15 January 2014 |
| Creators | Bordin, Thaisa Barizan |
| Contributors | Teixeira, Eduardo Rolim |
| Publisher | Pontif?cia Universidade Cat?lica do Rio Grande do Sul, Programa de P?s-Gradua??o em Odontologia, PUCRS, BR, Faculdade de Odontologia |
| Source Sets | IBICT Brazilian ETDs |
| Language | Portuguese |
| Detected Language | English |
| Type | info:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/masterThesis |
| Format | application/pdf |
| Source | reponame:Biblioteca Digital de Teses e Dissertações da PUC_RS, instname:Pontifícia Universidade Católica do Rio Grande do Sul, instacron:PUC_RS |
| Rights | info:eu-repo/semantics/openAccess |
| Relation | -8096554818733665164, 500, 600, 4673435736271820140 |
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