AUTHOR=Spuch Carlos, Antequera Desireé, Pascual Consuelo, Abilleira Soledad, Blanco María, Moreno-Carretero María José, Romero-López Jesús, Ishida Tetsuya, Molina Jose Antonio, Villarejo Alberto, Bermejo-Pareja Felix, Carro Eva TITLE=Soluble Megalin is Reduced in Cerebrospinal Fluid Samples of Alzheimer’s Disease Patients JOURNAL=Frontiers in Cellular Neuroscience VOLUME=9 YEAR=2015 URL=https://www.frontiersin.org/articles/10.3389/fncel.2015.00134 DOI=10.3389/fncel.2015.00134 ISSN=1662-5102 ABSTRACT=Megalin or low-density lipoprotein receptor-related protein-2 is a member of the low-density lipoprotein receptor family, which has been linked to Alzheimer’s disease (AD) by clearing brain amyloid β-peptide (Aβ) across the blood–cerebrospinal fluid barrier at the choroid plexus. Here, we found a soluble form of megalin secreted from choroid plexus epithelial cells. Soluble megalin levels were also localized in the human cerebrospinal fluid (CSF), being reduced in AD patients. We have also shown that soluble megalin binding to Aβ is decreased in the CSF of AD patients, suggesting that decreased sequestration of Aβ in the CSF could be associated with defective clearance of Aβ and an increase of brain Aβ levels. Thus, therapies, which increase megalin expression, at the choroid plexus and/or enhance circulating soluble megalin hold potential to control brain Aβ-related pathologies in AD.