title: Galectin-1 promotes basal and kainate-induced proliferation of neural progenitors in the dentate gyrus of adult mouse hippocampus.
abstract: We examined the expression of galectin-1, an endogenous lectin with one carbohydrate-binding domain, in the adult mouse hippocampus after systemic kainate administration. We found that the expression of galectin-1 was remarkably increased in activated astrocytes of the CA3 subregion and dentate gyrus of the hippocampus, and in nestin-positive neural progenitors in the dentate gyrus. Quantitative reverse transcription PCR (RT-PCR) analysis revealed that the galectin-1 mRNA level in hippocampus began to increase 1 day after kainate administration and that a 13-fold increase was attained within 3 days. Western blotting analysis confirmed that the level of galectin-1 protein increased to more than three-fold a week after the exposure. We showed that isolated astrocytes express and secrete galectin-1. To clarify the significance of the increased expression of galectin-1 in hippocampus, we compared the levels of hippocampal cell proliferation in galectin-1 knockout and wild-type mice after saline or kainate administration. The number of 5-bromo-2'-deoxyuridine (BrdU)-positive cells detected in the subgranular zone (SGZ) of galectin-1 knockout mice decreased to 62% with saline, and to 52% with kainate, as compared with the number seen in the wild-type mice. Most of the BrdU-positive cells in SGZ expressed doublecortin and neuron-specific nuclear protein, indicating that they are immature neurons. We therefore concluded that galectin-1 promotes basal and kainate-induced proliferation of neural progenitors in the hippocampus.
authors.affiliation: Division of Neurofunctional Genomics, Department of Immunobiology and Neuroscience, Medical Institute of Bioregulation, Kyushu University, Higashi-Ku, Fukuoka, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Kajitani
authors.forename: H
authors.initials: H
authors.lastname: Nomaru
authors.forename: M
authors.initials: M
authors.lastname: Ifuku
authors.forename: N
authors.initials: N
authors.lastname: Yutsudo
authors.forename: Y
authors.initials: Y
authors.lastname: Dan
authors.forename: T
authors.initials: T
authors.lastname: Miura
authors.forename: D
authors.initials: D
authors.lastname: Tsuchimoto
authors.forename: K
authors.initials: K
authors.lastname: Sakumi
authors.forename: T
authors.initials: T
authors.lastname: Kadoya
authors.forename: H
authors.initials: H
authors.lastname: Horie
authors.forename: F
authors.initials: F
authors.lastname: Poirier
authors.forename: M
authors.initials: M
authors.lastname: Noda
authors.forename: Y
authors.initials: Y
authors.lastname: Nakabeppu
mesh_terms: D000818:Animals; D049109:Cell Proliferation; D018891:Dentate Gyrus / Q000166:cytology / Q000378:metabolism; D037483:Galectin 1 / Q000235:genetics / Q000378:metabolism*; D007608:Kainic Acid / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009474:Neurons / Q000166:cytology / Q000502:physiology*; D013234:Stem Cells / Q000166:cytology / Q000378:metabolism*
chemical_list: D037483:Galectin 1; D007608:Kainic Acid