title: Impairments of astrocytes are involved in the d-galactose-induced brain aging.
abstract: Astrocyte dysfunction is implicated in course of various age-related neurodegenerative diseases. Chronic injection of d-galactose can cause a progressive deterioration in learning and memory capacity and serve as an animal model of aging. To investigate the involvement of astrocytes in this model, oxidative stress biomarkers, biochemical and pathological changes of astrocytes were examined in the hippocampus of the rats with six weeks of d-galactose injection. d-galactose-injected rats displayed impaired antioxidant systems, an increase in nitric oxide levels, and a decrease in reduced glutathione levels. Consistently, western blotting and immunostaining of glial fibrillary acidic protein showed extensive activation of astrocytes. Double-immunofluorescent staining further showed activated astrocytes highly expressed inducible nitric oxide synthase. Electron microscopy demonstrated the degeneration of astrocytes, especially in the aggregated area of synapse and brain microvessels. These findings indicate that impairments of astrocytes are involved in oxidative stress-induced brain aging by chronic injection of d-galactose.
authors.affiliation: Key Laboratory of Neurodegeneration of Jiangsu Province, Department of Anatomy, Histology and Pharmacology, Nanjing Medical University, 140 Hanzhong Road, Nanjing, Jiangsu 210029, China.
authors.forename: Ming
authors.initials: M
authors.lastname: Lei
authors.forename: Xiangdong
authors.initials: X
authors.lastname: Hua
authors.forename: Ming
authors.initials: M
authors.lastname: Xiao
authors.forename: Jiong
authors.initials: J
authors.lastname: Ding
authors.forename: Qunying
authors.initials: Q
authors.lastname: Han
authors.forename: Gang
authors.initials: G
authors.lastname: Hu
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D001253:Astrocytes / Q000187:drug effects / Q000502:physiology* / Q000648:ultrastructure; D015415:Biomarkers / Q000032:analysis; D016922:Cellular Senescence; D005690:Galactose / Q000008:administration & dosage / Q000633:toxicity*; D005978:Glutathione / Q000378:metabolism; D006624:Hippocampus / Q000187:drug effects / Q000502:physiology* / Q000648:ultrastructure; D007267:Injections; D008297:Male; D008854:Microscopy, Electron; D009569:Nitric Oxide / Q000378:metabolism; D052247:Nitric Oxide Synthase Type II / Q000378:metabolism; D018384:Oxidative Stress; D051381:Rats; D017207:Rats, Sprague-Dawley; D015854:Up-Regulation
chemical_list: D000975:Antioxidants; D015415:Biomarkers; D009569:Nitric Oxide; D052247:Nitric Oxide Synthase Type II; C496318:Nos2 protein, rat; D005978:Glutathione; D005690:Galactose