title: Increased oxidative stress in submitochondrial particles into the brain of rats submitted to the chronic mild stress paradigm.
abstract: Major depression is a common, serious and recurrent disorder, characterized by symptoms at the psychological, behavioral and physiological levels. Recent studies have suggested that reactive oxygen species (ROS) may play a role in the pathophysiology of bipolar disorder. The chronic mild stress (CMS) rat model has been used as an animal model of depression, since it induces some symptoms of a major depressive episode in humans (i.e. anhedonia). We investigated behavioral, physiological and neurochemical aspects of rats exposed for 40 days to CMS. Sweet food consumption, locomotor activity and body weight were assessed in stressed and control rats. We also investigated the potential involvement of ROS in the CMS model. Superoxide generation in submitochondrial particles from the rat hippocampus, prefrontal cortex and cortex was measured through superoxide-dependent oxidation of epinephrine to adrenochrome in a submitochondrial extract. We report that sweet food intake was reduced in rats subjected to CMS compared to controls. Further, CMS animals failed to gain body weight compared with non-stressed rats. Locomotor activity was not affected in stressed rats. An increase in superoxide production was detected in all brain structures analyzed. However, thiobarbituric acid reactive substances were increased only in cortex. In conclusion, these observations support the view that the CMS model of depression mimics alterations observed in depressed patients. The model affords a useful system in which to test the hypothesis that altered brain energy metabolism is associated with neuropsychiatric disorders.
authors.affiliation: Laboratório de Neurociências, Programa de Pós-Graduação em Ciências da Saúde, Unidade Acadêmica de Ciências da Saúde, Universidade do Extremo Sul Catarinense, Criciúma 88806-000, SC, Brazil.
authors.forename: Giancarlo
authors.initials: G
authors.lastname: Lucca
authors.forename: Clarissa M
authors.initials: CM
authors.lastname: Comim
authors.forename: Samira S
authors.initials: SS
authors.lastname: Valvassori
authors.forename: Gislaine Z
authors.initials: GZ
authors.lastname: Réus
authors.forename: Francieli
authors.initials: F
authors.lastname: Vuolo
authors.forename: Fabrícia
authors.initials: F
authors.lastname: Petronilho
authors.forename: Elaine C
authors.initials: EC
authors.lastname: Gavioli
authors.forename: Felipe
authors.initials: F
authors.lastname: Dal-Pizzol
authors.forename: João
authors.initials: J
authors.lastname: Quevedo
mesh_terms: D000818:Animals; D001835:Body Weight; D001921:Brain / Q000378:metabolism*; D002540:Cerebral Cortex / Q000378:metabolism; D002908:Chronic Disease; D003863:Depression / Q000209:etiology / Q000378:metabolism* / Q000503:physiopathology / Q000523:psychology*; D004195:Disease Models, Animal; D004435:Eating / Q000523:psychology; D006624:Hippocampus / Q000378:metabolism; D008297:Male; D009043:Motor Activity; D018384:Oxidative Stress; D017397:Prefrontal Cortex / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D013315:Stress, Psychological / Q000150:complications* / Q000523:psychology; D013367:Submitochondrial Particles / Q000378:metabolism*; D013481:Superoxides / Q000378:metabolism; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism
chemical_list: D017392:Thiobarbituric Acid Reactive Substances; D013481:Superoxides