title: Type 2 diabetes reduces the proliferation and survival of oligodendrocyte progenitor cells in ishchemic white matter lesions.
abstract: Diabetes mellitus (DM) is a major risk factor for stroke and it exacerbates tissue damage after ischemic insult. Diabetes is one of the important causes of the progression of white matter lesion, however, the pathological mechanisms remain unclear. The present study evaluated the influences of type 2 DM on ischemic subcortical white matter injury and the recruitment of oligodendrocyte progenitor cells (OPCs) under chronic cerebral hypoperfusion using type 2 diabetic (db/db) mice. After bilateral common carotid artery stenosis (BCAS), the rarefaction in the white matter was more severe in db/db mice than in db/+ mice, and the number of glutathione S-transferase-pi (GST-pi)-positive mature oligodendrocytes (OLG) was lower in db/db mice than in db/+ mice at 4 and 8 weeks after ischemia. There were no significant differences in the number of single-stranded DNA (ssDNA)-positive apoptotic cells in the deep white matter between the db/db and db/+ mice. We found a transient increase in the platelet-derived growth factor receptor-α (PDGFRα)-positive OPCs in white matter lesions after ischemia. However, significantly fewer PDGFRα-positive OPCs were detected in db/db than db/+ mice from 4weeks after BCAS. The number of Ki67-positive proliferating cells in the deep white matter was significantly lower in db/db mice than in db/+ mice from 4 to 8weeks after BCAS. Most of the Ki67-positive cells were PDGFRα-positive OPCs. Finally, we assessed the survival of 5-bromo-2'-deoxyuridine (BrdU)-positive proliferating cells in ischemic white matter, and found significantly poorer survival of BrdU/PDGFRα-positive OPCs or BrdU/GST-pi-positive OLGs in the db/db mice compared to the db/+ mice in the white matter after BCAS. Our findings suggest that the type 2 DM mice exhibited more severe white matter injury 8 weeks after chronic ischemia. Decreased proliferation and survival of OPCs may play an important role in the progression of white matter lesions after ischemia in diabetics.
authors.affiliation: Department of Neurology, Juntendo University School of Medicine, Tokyo, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Yatomi
authors.affiliation: Department of Neurology, Juntendo University School of Medicine, Tokyo, Japan. Electronic address: r_tanaka@juntendo.ac.jp.
authors.forename: R
authors.initials: R
authors.lastname: Tanaka
authors.affiliation: Department of Neurology, Juntendo University School of Medicine, Tokyo, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Shimada
authors.affiliation: Department of Neurology, Juntendo University School of Medicine, Tokyo, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Yamashiro
authors.affiliation: Research Institute for Diseases of Old Age, Juntendo University School of Medicine, Tokyo, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Liu
authors.affiliation: Department of Neurosurgery, Juntendo University School of Medicine, Tokyo, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Mitome-Mishima
authors.affiliation: Department of Neurology, Juntendo University Urayasu Hospital, Chiba, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Miyamoto
authors.affiliation: Department of Neurology, Juntendo University School of Medicine, Tokyo, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Ueno
authors.affiliation: Department of Neurology, Juntendo University Urayasu Hospital, Chiba, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Urabe
authors.affiliation: Department of Neurology, Juntendo University School of Medicine, Tokyo, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Hattori
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000502:physiology; D001921:Brain / Q000473:pathology / Q000503:physiopathology; D002545:Brain Ischemia / Q000473:pathology / Q000503:physiopathology*; D016893:Carotid Stenosis; D049109:Cell Proliferation / Q000502:physiology; D002470:Cell Survival / Q000502:physiology; D003924:Diabetes Mellitus, Type 2 / Q000473:pathology / Q000503:physiopathology*; D004195:Disease Models, Animal; D051549:Glutathione S-Transferase pi / Q000378:metabolism; D019394:Ki-67 Antigen / Q000378:metabolism; D008297:Male; D008810:Mice, Inbred C57BL; D008817:Mice, Mutant Strains; D058953:Neural Stem Cells / Q000473:pathology / Q000502:physiology*; D009836:Oligodendroglia / Q000473:pathology / Q000502:physiology*; D020796:Receptor, Platelet-Derived Growth Factor alpha / Q000378:metabolism; D066127:White Matter / Q000473:pathology / Q000503:physiopathology*
chemical_list: D019394:Ki-67 Antigen; D051549:Glutathione S-Transferase pi; D020796:Receptor, Platelet-Derived Growth Factor alpha
keywords: chronic ischemia; dementia; diabetes; oligodendrocyte progenitors; white matter lesion