title: Presence of conspecifics and their odor-impregnated objects reverse stress-decreased neurogenesis in mouse dentate gyrus.
abstract: Stress and corticosterone level are thought to negatively associate with neurogenesis in mammalian brains. Social support can diminish many adverse effects of stress. The present study examined the modulating effect of social support on stress-decreased cell proliferation and neuronal differentiation in a mouse model. A randomly-scheduled foot shock followed by restraint in water was used as a profound stress-provoking regimen. Bromodeoxyuridine (BrdU) staining was used to indicate newly mitotic cells and doublecortin (DCx) staining was used to reveal immature neurons. This stress-provoking regimen rapidly decreased BrdU- and BrdU/DCx-labeled cells in the dentate gyrus. However, such a stress-provoking regimen did not affect the number of these labeled cells in the subventricular zone. Familiar and unfamiliar mice' company throughout the stress regimen completely reversed the stress-decreased cell proliferation and neuronal genesis in the dentate gyrus. Likewise, both odor-familiar (from their home cages) and -unfamiliar (from cages other than their home cages) wooden blocks completely reversed the stress-decreased BrdU/DCx-labeled cells in the dentate gyrus. In contrast, wooden blocks free of any odor and camphor odor alone failed to affect the stress-decreased BrdU- or BrdU/DCx-labeled cells. Finally, we showed that conspecifics or their odors during the stress regimen reversed the stress-decreased cell proliferation and neuronal differentiation in the dentate gyrus via a corticosterone-independent mechanism. We conclude that stress and familiarity distinctively affect neurogenesis in the dentate gyrus and subventricular zone. Conspecific companions or presence of their odors reverse stress-decreased neurogenesis in the dentate gyrus, suggesting that social support during stress exposure may improve neurogenesis-related psychological functions.
authors: Department of Health Psychology, Chang Jung Christian University, Tainan, Taiwan.
authors: Chianfang G
authors: CG
authors: Cherng
authors: Pei-Syuan
authors: PS
authors: Lin
authors: Jia-Ying
authors: JY
authors: Chuang
authors: Wan-Ting
authors: WT
authors: Chang
authors: Yung-Shuan
authors: YS
authors: Lee
authors: Gour-Shenq
authors: GS
authors: Kao
authors: Yu-Ting
authors: YT
authors: Lai
authors: Lung
authors: L
authors: Yu
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001973:Bromodeoxyuridine / Q000378:metabolism; D002454:Cell Differentiation / Q000502:physiology; D049109:Cell Proliferation; D003345:Corticosterone / Q000097:blood; D018891:Dentate Gyrus / Q000503:physiopathology*; D004195:Disease Models, Animal; D000089622:Doublecortin Domain Proteins; D000089662:Doublecortin Protein; D004597:Electroshock / Q000009:adverse effects; D007124:Immunoenzyme Techniques / Q000379:methods; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D055495:Neurogenesis / Q000502:physiology*; D009479:Neuropeptides / Q000378:metabolism; D009812:Odorants; D012149:Restraint, Physical / Q000379:methods; D013315:Stress, Psychological / Q000209:etiology / Q000473:pathology* / Q000628:therapy*; D013550:Swimming / Q000523:psychology; D013997:Time Factors
chemical_list: C000714847:Dcx protein, mouse; D000089622:Doublecortin Domain Proteins; D000089662:Doublecortin Protein; D008869:Microtubule-Associated Proteins; D009479:Neuropeptides; D001973:Bromodeoxyuridine; D003345:Corticosterone