A research group led by Professor Noriko Osumi (Developmental Neuroscience) has found that cell proliferation and survival of newborn neurons were severely reduced in the hippocampus dentate gyrus (DG) in mice lacking ehprin-A5 function.

　It was once believed that neuron does not proliferate in adult brain. However, neurogenesis actually persists throughout life in the mammalian brain and is involved in various aspects in neuronal functions. Postnatal and adult neurogenesis in the mammalian forebrain occurs in two restricted areas, the subventricular zone of the lateral ventricle and the DG of the hippocampus. In the adult hippocampal DG, new granule neurons are continuously generated from putative stem cells that reside in the subgranular zone and are characterized by radial glial morphology and astrocytic features. Integration of newly born granule neurons into existing hippocampal neuronal circuits is functionally relevant for the maintenance of hippocampus-dependent spatial learning and memory. So its regulatory mechanism is expected to be clear.

　The research group investigated the role of ephrine-A5 in the adult hippocampal neurogenesis and found that ephrine-A5 is required for multiple aspects of the adult hippocampal neurogenesis. They also found impairment in microvasculature in the ephrine-A5 knockout mice, implying relationship between blood circulation and neurogenesis in the brain. This will open a new way to prevent and/or treat mental diseases due to decreased neurogenesis by improving brain blood circulation.

　The research results have published in the online edition of STEM CELLS on April 15, 2010 and will be appeared on the front cover of Volume 28 Issue 5 in May.

More Information (Japanese)

[Contact]

Professor Noriko Osumi

Tohoku University Graduate School of Medicine

TEL: +81-22-717-8201

Ｅ-mail: osumi*mail.tains.tohoku.ac.jp (Replace * with @)

[Public Relations]

Associate Professor Fuji Nagami

Tohoku Neuroscience Global COE

Tel: +81-22-717-7908, Fax: +81-22-717-7923

E-mail: f-nagami*mail.tains.tohoku.ac.jp (Replace * with @)