title: Immunoreactivity of glucose transporter 5 is located in epithelial cells of the choroid plexus and ependymal cells.
abstract: High fructose intake is associated with increased plasma triglyceride concentration, hepatic steatosis, impaired glucose tolerance, insulin resistance, and high blood pressure. In addition, increased fructose intake has recently been supposed to be a risk factor for dementia. However, direct effects of fructose on the brain function remain to be clarified. The localization of glucose transporter 5 (Glut5), a representative transporter of fructose, was immunohistochemically examined in the brains of humans, rats, and mice to clarify whether fructose was transported from the blood into the brain. Glut5 immunoreactivity was demonstrated to be located in the epithelial cells of the choroid plexus and the ependymal cells in the brains of humans and rats using commercial antibodies for Glut5. In addition, mRNA expression of mouse Glut5 was confirmed in the brains of mice. Immunohistochemical examination using a custom-made antibody against two regions of amino acid sequences of mouse Glut5 revealed that Glut5 immunoreactivity was also seen in the epithelial cells of the choroid plexus and the ependymal cells in the brains of mice. These findings show that Glut5 immunoreactivity is located in the epithelial cells of the choroid plexus and the ependymal cells, suggesting the possibility of the direct transportation of intravascular fructose into the brain parenchyma.
authors.affiliation: Department of Pathology and Host Defense Faculty of Medicine, Kagawa University, Kagawa 761-0793, Japan. Electronic address: masaueno@med.kagawa-u.ac.jp.
authors.forename: M
authors.initials: M
authors.lastname: Ueno
authors.affiliation: Life Sciences Research Center, Faculty of Medicine, Kagawa University, Kagawa 761-0793, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Nishi
authors.affiliation: Life Sciences Research Center, Faculty of Medicine, Kagawa University, Kagawa 761-0793, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Nakagawa
authors.affiliation: Department of Pathology and Host Defense Faculty of Medicine, Kagawa University, Kagawa 761-0793, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Chiba
authors.affiliation: Department of Pharmaco-Informatics, Faculty of Medicine, Kagawa University, Kagawa 761-0793, Japan.
authors.forename: I
authors.initials: I
authors.lastname: Tsukamoto
authors.affiliation: Maternal Perinatal Center, Faculty of Medicine, Kagawa University, Kagawa 761-0793, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Kusaka
authors.affiliation: Department of Anatomy and Neurobiology, Faculty of Medicine, Kagawa University, Kagawa 761-0793, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Miki
authors.affiliation: Department of Pathology and Host Defense Faculty of Medicine, Kagawa University, Kagawa 761-0793, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Sakamoto
authors.affiliation: Department of Cell Physiology, Faculty of Medicine, Kagawa University, Kagawa 761-0793, Japan.
authors.forename: F
authors.initials: F
authors.lastname: Yamaguchi
authors.affiliation: Department of Cell Physiology, Faculty of Medicine, Kagawa University, Kagawa 761-0793, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Tokuda
mesh_terms: D000328:Adult; D000368:Aged; D000818:Animals; D002831:Choroid Plexus / Q000737:chemistry* / Q000378:metabolism; D004847:Epithelial Cells / Q000737:chemistry* / Q000378:metabolism; D005260:Female; D051296:Glucose Transporter Type 5 / Q000032:analysis* / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D051379:Mice; D008809:Mice, Inbred C3H; D008875:Middle Aged; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D011921:Rats, Inbred WKY
chemical_list: D051296:Glucose Transporter Type 5; D012333:RNA, Messenger
keywords: 3,3′-diaminobenzidine tetrahydrochloride; 4′-6-diamidino-2-phenylindole; DAB; DAPI; Glut5; KLH; PB; PCR; PMSF; ROS; SDS–PAGE; choroid plexus; ependymal cell; fructose; glucose transporter 5; glut5; keyhole limpet hemocyanin; phenylmethylsulfonyl fluoride; phosphate buffer; polymerase chain reaction; reactive oxygen species; sodium dodecyl sulfate polyacrylamide gel electrophoresis