Desenvolvimento de sistemas farmacêuticos emulsionados para veiculação gênica

• Ano de defesa: 2007
• Autor(a) principal: Veríssimo, Lourena Mafra
• Orientador(a): Egito, Eryvaldo Sócrates Tabosa do
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal do Rio Grande do Norte
• Programa de Pós-Graduação: Programa de Pós-Graduação em Genética e Biologia Molecular
• Departamento: Genética e Biologia Molecular
• País: BR
• Palavras-chave em Português: Terapia gênica; Emulsões catiônicas; Surfactantes catiônicos; Estabilidade de emulsões
• Palavras-chave em Inglês: Gene therapy; Cationic emulsions; Cationic surfactants; Emulsion stability
• Área do conhecimento CNPq: CNPQ::CIENCIAS BIOLOGICAS::GENETICA::GENETICA MOLECULAR E DE MICROORGANISMOS
• Link de acesso: https://repositorio.ufrn.br/jspui/handle/123456789/16784

Broadly speaking, the concept of gene therapy involves the transfer of a genetic material into a cell, tissue, or organ in order to cure a disease or at least improve the clinical status of a patient. Making it simple, gene therapy consists in the insertion of functional genes into cells containing defective genes by substituting, complementing or inhibiting them. The achievement of a foreigner DNA expression into a population of cells requires its transfer to the target. Therefore, it is a key issue to create systems able to transfer and protect the DNA until it reaches the target, the vectors. The disadvantages related to the use of viral vectors have encouraged efforts to develop emulsions as non-viral vectors. In fact, they are easily produced, present controllable stability and enable transfection. The aim of this work was to develop an emulsion for gene therapy and evaluate its ability to compact nucleic acids by the development of a complex with the plasmid pIRES2-EGFP. The first step was to determine the Hydrophilic Lipophilic Balance (HLB) of the Captex® 355 (oily internal phase of the emulsion) through long and short term stability assays. Based on the results, emulsions composed of Captex® 355, Tween 20® and Span 60® with 10.7 HLB were produced by three different methods: phase inversion, spontaneous emulsification and sonication. The results showed that the lowest diameter and best stability of the emulsions were achieved by the sonication method. The cationic emulsions were made by adding DOTAP to the basic emulsion. Its association with pIRES2-EGFP was evaluated by electrophoresis. Several rates of emulsion and DNA were evaluated and the results showed that 100% of the complex was formed when the rate DOTAP/DNA(nmol/µg) was 130. In conclusion, the overall results show the ability of the proposed emulsion to compact pIRES2-EGFP, which is a requirement to a successful transfection. Therefore, such formulation may be considered a promising candidate for gene therapy