Injury-induced neurogenesis in the mammalian forebrain

Division of Systems Medical Science, Institute for Comprehensive Medical Science, Fujita Health University, Toyoake, Aichi, 470-1192, Japan.
Cellular and Molecular Life Sciences CMLS (Impact Factor: 5.86). 11/2010; 68(10):1645-56. DOI: 10.1007/s00018-010-0552-y
Source: PubMed

ABSTRACT It has been accepted that new neurons are added to the olfactory bulb and the hippocampal dentate gyrus throughout life in the healthy adult mammalian brain. Recent studies have clarified that brain insult raises the proliferation of neural stem cells/neural progenitor cells existing in the subventricular zone and the subgranular zone, which become sources of new neurons for the olfactory bulb and the dentate gyrus, respectively. Interestingly, convincing data has shown that brain insult invokes neurogenesis in various brain regions, such as the hippocampal cornu ammonis region, striatum, and cortex. These reports suggest that neural stem cells/neural progenitor cells, which can be activated by brain injury, might be broadly located in the adult brain or that new neurons may migrate widely from the neurogenic regions. This review focuses on brain insult-induced neurogenesis in the mammalian forebrain, especially in the neocortex.

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Available from: Koji Ohira, Aug 11, 2015
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    • "Adult neurogenesis is regulated by the interplay between intrinsic and extrinsic factors [114]. Particularly, hypoxia was shown to trigger neurogenesis in the adult brain [115]. Compelling evidence derived from in vitro studies revealed that the exposure of neural progenitor cell (NPC) populations to reduced oxygen levels (e.g. "
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    • "A common reaction in damaged brain tissue is cell proliferation, whether in glia or neural stem cells (Ohira, 2011; Robel et al., 2011). The timecourse of these events has been described for four-day binge exposure (Nixon and Crews, 2004; Nixon et al., 2008); therefore we examined these brains for binge-induced proliferation events via BrdU labeling. "
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    • "FLX solution was intraperitoneally injected into mice every day for 3 weeks, and the appropriate FLX concentration was determined for each body weight. FLX pellet treatment was performed as described previously (Ohira and Miyakawa, 2011). The drug pellets contained 7.245 mg or 20.7 mg FLX; these dosages were calculated so that a mouse with a body weight of 23 g received FLX at 15 mg/kg/ day for 21 days or 60 days, respectively (Innovative Research of America, Sarasota, FL). "
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