DANIELA PERRONI FRIAS
Projetos de Pesquisa
Unidades Organizacionais
LIM/05 - Laboratório de Poluição Atmosférica Experimental, Hospital das Clínicas, Faculdade de Medicina
2 resultados
Resultados de Busca
Agora exibindo 1 - 2 de 2
- Human bronchial epithelial cells exposed in vitro to diesel exhaust particles exhibit alterations in cell rheology and cytotoxicity associated with decrease in antioxidant defenses and imbalance in pro- and anti-apoptotic gene expression(2016) SERIANI, Robson; SOUZA, Claudia Emanuele Carvalho de; KREMPEL, Paloma Gava; FRIAS, Daniela Perroni; MATSUDA, Monique; CORREIA, Aristides Tadeu; FERREIRA, Marcia Zotti Justo; ALENCAR, Adriano Mesquita; NEGRI, Elnara Marcia; SALDIVA, Paulo Hilario Nascimento; MAUAD, Thais; MACCHIONE, MariangelaDiesel exhaust particles (DEPs) from diesel engines produce adverse alterations in cells of the airways by activating intracellular signaling pathways and apoptotic gene overexpression, and also by influencing metabolism and cytoskeleton changes. This study used human bronchial epithelium cells (BEAS-2B) in culture and evaluates their exposure to DEPs (15ug/mL for 1 and 2 h) in order to determine changes to cell rheology (viscoelasticity) and gene expression of the enzymes involved in oxidative stress, apoptosis, and cytotoxicity. BEAS-2B cells exposed to DEPs were found to have a significant loss in stiffness, membrane stability, and mitochondrial activity. The genes involved in apoptosis [B cell lymphoma 2 (BCL-2 and caspase-3)] presented inversely proportional expressions (p=0.05, p=0.01, respectively), low expression of the genes involved in antioxidant responses [SOD1 (superoxide dismutase 1); SOD2 (superoxide dismutase 2), and GPx (glutathione peroxidase) (p=0.01)], along with an increase in cytochrome P450, family 1, subfamily A, polypeptide 1 (CYP1A1) (p=0.01). These results suggest that alterations in cell rheology and cytotoxicity could be associated with oxidative stress and imbalance between pro-and antiapoptotic genes.
- Nrf2 positively regulates autophagy antioxidant response in human bronchial epithelial cells exposed to diesel exhaust particles(2020) FRIAS, Daniela Perroni; GOMES, Raquel Labiapari Nunes; YOSHIZAKI, Kelly; CARVALHO-OLIVEIRA, Regiani; MATSUDA, Monique; JUNQUEIRA, Mara de Souza; TEODORO, Walcy Rosolia; VASCONCELLOS, Perola de Castro; PEREIRA, Daniela Cristina de Almeida; CONCEICAO, Paulo Roberto da; SALDIVA, Paulo Hilario Nascimento; MAUAD, Thais; MACCHIONE, MariangelaDiesel exhaust particles (DEP) are known to generate reactive oxygen species in the respiratory system, triggering cells to activate antioxidant defence mechanisms, such as Keap1-Nrf2 signalling and autophagy. The aim of this study was to investigate the relationship between the Keap1-Nrf2 signalling and autophagy pathways after DEP exposure. BEAS-2B cells were transfected with silencing RNA (siRNA) specific to Nrf2 and exposed to DEP. The relative levels of mRNA for Nrf2, NQO1, HO-1, LC3B, p62 and Atg5 were determined using RT-PCR, while the levels of LCB3, Nrf2, and p62 protein were determined using Western blotting. The autophagy inhibitor bafilomycin caused a significant decrease in the production of Nrf2, HO-1 and NQO1 compared to DEPs treatment, whereas the Nrf2 activator sulforaphane increased the LC3B (p = 0.020) levels. BEAS-2B cells exposed to DEP at a concentration of 50 mu g/mL for 2 h showed a significant increase in the expression of LC3B (p = 0.001), p62 (p = 0.008), Nrf2 (p = 0.003), HO-1 (p = 0.001) and NQO1 (p = 0.015) genes compared to control. In siRNA-transfected cells, the LC3B (p < 0.001), p62 (p = 0.001) and Atg5 (p = 0.024) mRNA levels and the p62 and LC3II protein levels were decreased, indicating that Nrf2 modulated the expression of autophagy markers (R < 1). These results imply that, in bronchial cells exposed to DEP, the Nrf2 system positively regulates autophagy to maintain cellular homeostasis.