title: Chronic unpredictable stress impairs endogenous antioxidant defense in rat brain.
abstract: Many studies have shown that chronic stress can cause neuronal damage and depression, but this exact mechanism still remains unknown. Neurons are vulnerable to lipid peroxidation-induced damage because the major part of neuronal cell membrane is polyunsaturated fatty acids that are substrate for reactive oxygen species. Since endogenous antioxidant defense systems normally eliminate production of reactive oxygen species, deficient antioxidant defense can cause oxidative stress-induced damage. In the present study, to understand the role of endogenous antioxidant defense in chronic stress-induced neuronal damage, we analyzed lipid peroxidation, total antioxidant capacity, and activities of catalase and glutathione peroxidase in frontal cortex, hippocampus and striatum of rats exposed to chronic unpredictable stress. We found that chronic unpredictable stress for four weeks in rats induced depressive-like behaviors such as anhedonia, despair and decreased exploration. Malondialdehyde, a lipid peroxidation product, is increased, but total antioxidant capacity, glutathione peroxidase activity and catalase activity are decreased in brain of rats exposed to chronic unpredictable stress. Our findings suggest that down regulation of endogenous antioxidant defense induces lipid peroxidation contributing a role to chronic stress and depression.
authors.affiliation: Medical College of Soochow University, Suzhou, PR China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Che
authors.affiliation: Medical College of Soochow University, Suzhou, PR China; Kleysen Institute for Advanced Medicine, Health Sciences Centre, Winnipeg, Canada; Department of Pharmacology and Therapeutics, University of Manitoba, Winnipeg, Canada.
authors.forename: Zhu
authors.initials: Z
authors.lastname: Zhou
authors.affiliation: Medical College of Soochow University, Suzhou, PR China.
authors.forename: Yuxin
authors.initials: Y
authors.lastname: Shu
authors.affiliation: Medical College of Soochow University, Suzhou, PR China.
authors.forename: Chao
authors.initials: C
authors.lastname: Zhai
authors.affiliation: Medical College of Soochow University, Suzhou, PR China.
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Zhu
authors.affiliation: Medical College of Soochow University, Suzhou, PR China.
authors.forename: Songjie
authors.initials: S
authors.lastname: Gong
authors.affiliation: Medical College of Soochow University, Suzhou, PR China.
authors.forename: Yonghua
authors.initials: Y
authors.lastname: Cui
authors.affiliation: Kleysen Institute for Advanced Medicine, Health Sciences Centre, Winnipeg, Canada; Department of Pharmacology and Therapeutics, University of Manitoba, Winnipeg, Canada; Department of Psychiatry, University of Manitoba, Winnipeg, Canada. Electronic address: jun-feng.wang@med.umanitoba.ca.
authors.forename: Jun-Feng
authors.initials: JF
authors.lastname: Wang
mesh_terms: D059445:Anhedonia; D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D001921:Brain / Q000378:metabolism*; D002374:Catalase / Q000378:metabolism; D003342:Corpus Striatum / Q000378:metabolism; D005106:Exploratory Behavior; D005625:Frontal Lobe / Q000378:metabolism; D005979:Glutathione Peroxidase / Q000378:metabolism; D006624:Hippocampus / Q000378:metabolism; D015227:Lipid Peroxidation; D008297:Male; D017207:Rats, Sprague-Dawley; D013315:Stress, Psychological / Q000378:metabolism* / Q000523:psychology
chemical_list: D000975:Antioxidants; D002374:Catalase; D005979:Glutathione Peroxidase
keywords: Antioxidant capacity; Catalase; Chronic unpredictable stress; Depression; Glutathione peroxidase; Lipid peroxidation