title: Down-regulation of IGF-1/IGF-1R in hippocampus of rats with vascular dementia.
abstract: Insulin-like growth factor-1 (IGF-1) has been demonstrated to have neuroprotective effects, but little is known concerning its role in vascular dementia (VaD). This study aimed to evaluate expression of IGF-1 signaling in hippocampus in rat model of VaD, and probe the underlying mechanisms. Permanent occlusion of bilateral common carotid arteries (2-VO) was used as VaD model. Learning and memory functions were declined significantly in 2-VO rats, and these impairments were further deteriorated with the prolongation of 2-VO treatment. IGF-1, IGF-1 receptor (IGF-1R), total Akt and phosphorylated Akt (p-Akt) were all measured at 1, 2 and 4 months following 2-VO injury. Compared with controls, IGF-1, IGF-1 mRNA and p-Akt expression were significantly decreased in hippocampus of 2-VO rats. However, changes of IGF-1R and total Akt levels were not significant. These results suggest that down-regulation of IGF-1 and p-Akt may contribute to the impairments of learning and memory functions after 2-VO. IGF-1/IGF-1R signaling system may involved in the onset and development of VaD.
authors.affiliation: Department of Neurology, Jinling hospital, Nanjin University School of Medicine, 305# East Zhongshan Road, Nanjing 210002, Jiangsu Province, China.
authors.forename: Xiuqun
authors.initials: X
authors.lastname: Gong
authors.forename: Minmin
authors.initials: M
authors.lastname: Ma
authors.forename: Xinying
authors.initials: X
authors.lastname: Fan
authors.forename: Mingquan
authors.initials: M
authors.lastname: Li
authors.forename: Qian
authors.initials: Q
authors.lastname: Liu
authors.forename: Xinfeng
authors.initials: X
authors.lastname: Liu
authors.forename: Gelin
authors.initials: G
authors.lastname: Xu
mesh_terms: D000818:Animals; D015153:Blotting, Western; D017536:Carotid Artery, Common / Q000502:physiology; D015140:Dementia, Vascular / Q000378:metabolism* / Q000523:psychology; D015536:Down-Regulation / Q000502:physiology; D004797:Enzyme-Linked Immunosorbent Assay; D006624:Hippocampus / Q000378:metabolism*; D007334:Insulin-Like Growth Factor I / Q000096:biosynthesis*; D008297:Male; D018782:Maze Learning / Q000502:physiology; D008568:Memory / Q000502:physiology; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D051381:Rats; D017207:Rats, Sprague-Dawley; D060888:Real-Time Polymerase Chain Reaction; D017526:Receptor, IGF Type 1 / Q000096:biosynthesis*
chemical_list: D012333:RNA, Messenger; D007334:Insulin-Like Growth Factor I; D017526:Receptor, IGF Type 1; D051057:Proto-Oncogene Proteins c-akt