Estudo de interação entre um hormônio estrógeno e modelos simples de membrana biológica

• Ano de defesa: 2015
• Autor(a) principal: Stunges, Gabriele Marques [UNESP]
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Estadual Paulista (Unesp)
• Palavras-chave em Português: Filmes finos multifolhados; Hormonios esteroidianos; Membranas (Biologia); Thin films, Multilayered
• Link de acesso: http://hdl.handle.net/11449/126575; http://www.athena.biblioteca.unesp.br/exlibris/bd/cathedra/14-08-2015/000844280.pdf

The 17 Þ - ethinyl estradiol (EE 2) is a synthetic steroid hormone with poor water solbility. Contamination by that estrogen has the origin in continuous introduction into aquatic environments through the improper disposal of domestic and industrial sewage, as well as the use of activated sludge wastewater treatment plants in agriculture. Exposure to this compound has been linked to breast cancer causes, male infertility and small mutations in living organisms such as fish, whose effects can be associated with the interaction of the hormone with the cell membrane. Thus, the study of membrane models in the form of Langmuir films exposed to EE2 in subphase was carried out to evaluate the interaction membrane/hormone. Monolayers composed of amphiphilic molecules with different charges were spread on ultrapure water subphase containing EE2, and the interaction membrane/hormone studied by surface pressure vs. mean molecular area isotherms (л - A isotherms). This study used the phospholipids dipalmitoyl phosphatidyl choline (DPPC), which is zwitterionic, dipalmitoyl phosphatidyl glycerol (DPPG), which is anionic, and the surfactant dimethyl dioctadecyl ammonium bromide (DODAB), which is cationic. The stearic acid (SA) was used to obtain a better understanding of the interaction of EE2 with DPPC and DPPG. All molecules used as membrane models presented interactions with EE2, according to л - A isotherms, which was confirmed by spectroscopic reflection and absorption in the infrared polarization modulation (PM-IRRAS). The studies have shown that interactions occur through electrostatic interations, especially in the polar region of lipids, involving not only cationic and anionic group but also the groups C=O and P=O the lipids with OH group of EE2