title: Effect of myricetin, pyrogallol, and phloroglucinol on yeast resistance to oxidative stress.
abstract: The health beneficial effects of dietary polyphenols have been attributed to their intrinsic antioxidant activity, which depends on the structure of the compound and number of hydroxyl groups. In this study, the protective effects of pyrogallol, phloroglucinol, and myricetin on the yeast Saccharomyces cerevisiae were investigated. Pyrogallol and myricetin, which have a pyrogallol structure in the B ring, increased H2O2 resistance associated with a reduction in intracellular oxidation and protein carbonylation, whereas phloroglucinol did not exert protective effects. The acquisition of oxidative stress resistance in cells pretreated with pyrogallol and myricetin was not associated with an induction of endogenous antioxidant defences as assessed by the analysis of superoxide dismutase and catalase activities. However, myricetin, which provided greater stress resistance, prevented H2O2-induced glutathione oxidation. Moreover, myricetin increased the chronological lifespan of yeast lacking the mitochondrial superoxide dismutase (Sod2p), which exhibited a premature aging phenotype and oxidative stress sensitivity. These findings show that the presence of hydroxyl groups in the ortho position of the B ring in pyrogallol and myricetin contributes to the antioxidant protection afforded by these compounds. In addition, myricetin may alleviate aging-induced oxidative stress, particularly when redox homeostasis is compromised due to downregulation of endogenous defences present in mitochondria.
authors.affiliation: Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen s/n, 4200-135 Porto, Portugal ; IBMC, Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua do Campo Alegre 823, 4150-180 Porto, Portugal ; ICBAS, Instituto de Ciências Biomédicas Abel Salazar, Departamento de Biologia Molecular, Universidade do Porto, Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal ; REQUIMTE/LAQV, Faculdade de Ciências da Universidade do Porto, Rua do Campo Alegre s/n, 4169-007 Porto, Portugal.
authors.forename: Vanda
authors.initials: V
authors.lastname: Mendes
authors.affiliation: Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen s/n, 4200-135 Porto, Portugal ; IBMC, Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua do Campo Alegre 823, 4150-180 Porto, Portugal.
authors.forename: Rita
authors.initials: R
authors.lastname: Vilaça
authors.affiliation: REQUIMTE/LAQV, Faculdade de Ciências da Universidade do Porto, Rua do Campo Alegre s/n, 4169-007 Porto, Portugal.
authors.forename: Victor
authors.initials: V
authors.lastname: de Freitas
authors.affiliation: Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen s/n, 4200-135 Porto, Portugal ; IBMC, Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua do Campo Alegre 823, 4150-180 Porto, Portugal ; ICBAS, Instituto de Ciências Biomédicas Abel Salazar, Departamento de Biologia Molecular, Universidade do Porto, Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal.
authors.forename: Pedro Moradas
authors.initials: PM
authors.lastname: Ferreira
authors.affiliation: REQUIMTE/LAQV, Faculdade de Ciências da Universidade do Porto, Rua do Campo Alegre s/n, 4169-007 Porto, Portugal.
authors.forename: Nuno
authors.initials: N
authors.lastname: Mateus
authors.affiliation: Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen s/n, 4200-135 Porto, Portugal ; IBMC, Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua do Campo Alegre 823, 4150-180 Porto, Portugal ; ICBAS, Instituto de Ciências Biomédicas Abel Salazar, Departamento de Biologia Molecular, Universidade do Porto, Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal.
authors.forename: Vítor
authors.initials: V
authors.lastname: Costa
mesh_terms: D002374:Catalase / Q000378:metabolism; D005419:Flavonoids / Q000494:pharmacology*; D005978:Glutathione / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000633:toxicity; D008928:Mitochondria / Q000378:metabolism; D018384:Oxidative Stress / Q000187:drug effects; D010696:Phloroglucinol / Q000494:pharmacology*; D050050:Protein Carbonylation / Q000187:drug effects; D011748:Pyrogallol / Q000494:pharmacology*; D017382:Reactive Oxygen Species / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D005419:Flavonoids; D017382:Reactive Oxygen Species; D029701:Saccharomyces cerevisiae Proteins; D011748:Pyrogallol; C040015:myricetin; D006861:Hydrogen Peroxide; D010696:Phloroglucinol; D002374:Catalase; D013482:Superoxide Dismutase; D005978:Glutathione