title: Expression of a membrane-bound form of the ferroxidase ceruloplasmin by leptomeningeal cells.
abstract: Ceruloplasmin is a key enzyme involved in detoxifying ferrous iron, which can generate free radicals. The secreted form of ceruloplasmin is produced by the liver and is abundant in serum. We have previously identified a membrane-bound glycosylphosphatidylinositol (GPI)-anchored form of ceruloplasmin (GPI-Cp) that is expressed by astrocytes in the central nervous system (CNS) (Patel and David. 1997. J Biol Chem 272:20185-20190). We now provide direct evidence that rat leptomeningeal cells, which cover the surface of the brain, also express GPI-Cp. The expression of GPI-Cp on the surface of these cells increases with postnatal development and is regulated in vitro by cell density, time in culture, and various extracellular matrix molecules. The expression of GPI-Cp also appears to be regulated differently in astrocytes and leptomeningeal cells in vitro. The abundant expression of GPI-Cp on the surface of leptomeningeal cells suggests that these cells play a role in antioxidant defense along the surface of the postnatal CNS possibly by detoxifying the cerebrospinal fluid.
authors.affiliation: Centre for Research in Neuroscience, Montreal General Hospital Research Institute, McGill University, Montreal, Quebec, Canada.
authors.forename: Bina
authors.initials: B
authors.lastname: Mittal
authors.forename: Mohammad M
authors.initials: MM
authors.lastname: Doroudchi
authors.forename: Suh Young
authors.initials: SY
authors.lastname: Jeong
authors.forename: Bharatkumar N
authors.initials: BN
authors.lastname: Patel
authors.forename: Samuel
authors.initials: S
authors.lastname: David
mesh_terms: D000818:Animals; D002462:Cell Membrane / Q000201:enzymology*; D002478:Cells, Cultured; D002570:Ceruloplasmin / Q000096:biosynthesis* / Q000235:genetics; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology; D017261:Glycosylphosphatidylinositols / Q000096:biosynthesis; D008578:Meninges / Q000166:cytology / Q000201:enzymology* / Q000254:growth & development*; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D017261:Glycosylphosphatidylinositols; D002570:Ceruloplasmin