Efeito comparativo entre a angiotensina-(1-7) e o novo agonista do receptor MAS, CGEN 856S, nas vias AKT/eNOS e AKT/FOXO1 utilizando modelos celulares

• Ano de defesa: 2014
• Autor(a) principal: Antonio Augusto Bastos Peluso
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Minas Gerais; UFMG
• Palavras-chave em Português: Ciências Biológicas: Fisiologia e Farmacologia; Sistema renina-angiotensina Fisiologia; Receptor MAS; Sinalização intracelular; Fisiologia
• Link de acesso: http://hdl.handle.net/1843/BUBD-9NBKEF

Biotechnology studies based on a computational platform developed by Compugen, Tel Aviv, Israel - allowed the discovery of a potential Mas agonist, CGEN 856S, which produces several effects resembling those produced by Angiotensin-(1-7) [Ang-(1-7)], including anti-hypertensive and cardioprotective effects, such as decrease of ischemia, renal and cardiac fibrosis reduction and vasodilation nitric oxide (NO) dependent. Moreover, CGEN 8566S attenuates isoproterenol-induced cardiac remodeling and myocardial infarction injury. Studies using phosphoproteomics have shown that Ang-(1-7) promotes FOXO1 activation and nuclear translocation in human aortic endothelial cells (HAEC). It is not clear, however, whether CGEN 856S is capable to activate the same intracellular pathways than those previously demonstrated for Ang-(1-7). This study evaluated and compared the effect of CGEN 856S and Ang-(1-7) on AKT/eNOS and AKT/FOXO1 activation, using different cell types. Mas-transfected CHO (Chinese Hamster Ovary - CHO-Mas) cells were stimulated with CGEN 856S and Ang-(1-7). Non-transfected CHO cells were used as control. The protein extract was used for, AKT, phospho-AKT, phospho-eNOS, phospho-FOXO1, Mas and GAPDH detection by western blot. CHO-Mas and CHO cells were also exposed to both peptides for NO release measurement, through DAF-FM incorporation technique. HAEC, A549 and DU145 (human tumoral linages from lungs and prostate, respectively) cells were treated with CGEN 856S and Ang-(1-7) with or without previous A779 treatment. The cells were used for immunolocalization of FOXO1, analyzed by confocal microscope and the nuclear fluorescence intensity was quantified. A549 and DU145 cells were also used for cytotoxicity test, being treated with a combination of PI3 kinase inhibitors wortmannin or LY294002 in different concentrations and CGEN856S or Ang-(1-7). The results showed a significant increase phosphorylation of AKT, eNOS as well as the dephosphorylation of FOXO1 only in CHO-Mas cells treated with CGEN856S and Ang-(1-7). CHO-Mas transfect cells treated with CGEN 856S and Ang-(1-7) also promoted a significant release of NO compared with CHO-Mas non-treated cell. No differences were observed in CHO non-transfected cells. HAEC, A549 and DU145 cell types treated with CGEN 856S and Ang-(1-7) showed a significant FOXO1 nuclear translocation. A779 blocked this effect, at least partly. In both A549 and DU145 cells, the combination of the PI3 kinase inhibitors wortmannin and LY294002 with CGEN 856S or Ang-(1-7) showed a potentiated anti-proliferative effect. These data suggest that CGEN 856S and Ang-(1-7) as agonists of Mas receptor had similar effects, and thus represent a potential therapeutic target in cancer and cardiovascular pathologies.