Contrasting roles of oxidized lipids in modulating membrane microdomains

Autor(es)

Tsubone, Tayana Mazin ^[1] ; Junqueira, Helena Couto ^[2] ; Baptista, Mauricio S. ^[2] ; Itri, Rosangela ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Phys, Dept Appl Phys, Sao Paulo, SP - Brazil

^[2] Univ Sao Paulo, Inst Chem, Dept Biochem, Sao Paulo, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES; v. 1861, n. 3, p. 660-669, MAR 1 2019.
• Citações Web of Science: 4

Resumo

Lipid rafts display a lateral heterogeneity forming membrane microdomains that hold a fundamental role on biological membranes and are indispensable to physiological functions of cells. Oxidative stress in cellular environments may cause lipid oxidation, changing membrane composition and organization, thus implying in effects in cell signaling and even loss of homeostasis. The individual contribution of oxidized lipid species to the formation or disruption of lipid rafts in membranes still remains unknown. Here, we investigate the role of different structures of oxidized phospholipids on rafts microdomains by carefully controlling the membrane composition. Our experimental approach based on fluorescence microscopy of giant unilamellar vesicles (GUV) enables the direct visualization of the impact of hydroperoxidized POPC lipid (referred to as POPCOOH) and shortened chain lipid PazePC (1-palmitoyl-2-azelaoyl-sn-glycero-3-phosphocholine) on phase separation. We found that the molecular structure of oxidized lipid is of paramount importance on lipid mixing and/or de mixing. The hydrophobic mismatch promoted by POPCOOH coupled to its cylindrical molecular shape favor microdomains formation. In contrast, the conical shape of PazePC causes disarrangement of lipid 2D organized platforms. Our findings contribute to better unraveling how oxidized phospholipids can trigger formation or disruption of lipid rafts. As a consequence, phospholipid oxidation may indirectly affect association or dissociation of key biomolecules in the rafts thus altering cell signaling and homeostasis. (AU)

• Processo FAPESP: 11/00963-8 - Mecanismos de fotossensibilização em membranas lipídicas: o papel de hidroperóxidos de lipídios e a formação de domínios.
• Beneficiário: Helena Couto Junqueira
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 14/20107-7 - Oxidação lipídica em biofísica de membranas e celular: de nanosensores funcionais ao impacto sobre a formação de amiloides. Aplicação de técnicas avançadas de fluorescência, espalhamento de RX e microscopias
• Beneficiário: Rosangela Itri
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 12/50680-5 - Fotossensibilização nas ciências da vida
• Beneficiário: Mauricio da Silva Baptista
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 16/23071-9 - Fotossensibilização em membranas miméticas lisossomais para investigação do mecanismo de morte celular associada a autofagia.
• Beneficiário: Tayana Mazin Tsubone
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado