title: Time-related increase in mitochondrial superoxide production, biomolecule damage and antioxidant enzyme activities in cortical astrocyte cultures.
abstract: According to the free radical theory of aging, biological senescence processes develop from a general failure to maintain organism's homeostasis, probably due to oxidative stress. The brain is particularly susceptible to oxidative damage, and astrocytes are chiefly responsible for its antioxidant defense. Here we evaluated and compared the enzymatic antioxidant activities, mitochondrial superoxide production, and oxidative damage in biomolecule in cortex astrocytes from newborn Wistar rats maintained for 10-13 or 40-47 days in culture. We show that, besides an increase in antioxidant enzyme activities in matured astrocyte cultures, there was an increase in lipoperoxidation and in protein oxidation, probably due to an increase in mitochondrial electron transport chain superoxide production. This could indicate that the increasing in defense mechanisms was not sufficient to avoid oxidative biomolecule damage during maturation.
authors.affiliation: Departamento de Bioquímica, ICBS, Universidade Federal do Rio, Grande do Sul, Rua Ramiro Barcelos, 2600-Anexo 90035-003, Porto Alegre, RS, Brazil.
authors.forename: Fábio
authors.initials: F
authors.lastname: Klamt
authors.forename: Carmem
authors.initials: C
authors.lastname: Gottfried
authors.forename: Francine
authors.initials: F
authors.lastname: Tramontina
authors.forename: Felipe
authors.initials: F
authors.lastname: Dal-Pizzol
authors.forename: Mario Luis Conte
authors.initials: ML
authors.lastname: Da Frota
authors.forename: José Cláudio Fonseca
authors.initials: JC
authors.lastname: Moreira
authors.forename: Renato D
authors.initials: RD
authors.lastname: Dias
authors.forename: Emilio
authors.initials: E
authors.lastname: Moriguchi
authors.forename: Susana
authors.initials: S
authors.lastname: Wofchuk
authors.forename: Diogo O
authors.initials: DO
authors.lastname: Souza
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D001253:Astrocytes / Q000166:cytology* / Q000201:enzymology*; D002478:Cells, Cultured; D016922:Cellular Senescence / Q000502:physiology; D002540:Cerebral Cortex / Q000166:cytology; D008928:Mitochondria / Q000201:enzymology*; D018384:Oxidative Stress / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar; D013481:Superoxides / Q000378:metabolism
chemical_list: D000975:Antioxidants; D013481:Superoxides