title: Apolipoprotein E highly correlates with AbetaPP- and tau-related markers in human cerebrospinal fluid.
abstract: We assessed cerebrospinal fluid (CSF) levels of apolipoprotein E (apoE), phospholipid transfer protein (PLTP) activity, cholesterol, secreted amyloid-beta protein precursor alpha and beta (sAbetaPPalpha, sAbetaPPbeta), amyloid-beta peptides 1-40 (Abeta_{40}) and 1-42 (Abeta_{42}), total tau and tau phosphorylated at threonine 181 (pTau) in neurologically healthy, cognitively intact adults. ApoE significantly correlated with sAbetaPPalpha (r = 0.679), sAbetaPPbeta (r = 0.634), Abeta_{40} (r = 0.609), total and pTau (r = 0.589 and r = 0.673, respectively, all p < 0.001), PLTP activity (r = 0.242, p = 0.002) and cholesterol (r = 0.194, p < 0.01). PLTP activity significantly correlated with sAbetaPPalpha (r = 0.292), sAbetaPPbeta (r = 0.281), total and pTau (r = 0.265 and 0.258, respectively; all p <or= 0.001). Using partial correlations of CSF biomarkers with apoE, PLTP activity, age and gender, apoE remained significantly correlated with sAbetaPPalpha, sAbetaPPbeta, Abeta_{40}, total and pTau (p < 0.001). The presence of apoE epsilon2 was associated with lower levels of apoE, PLTP activity and Abeta_{42}, while APOEepsilon4} had no significant impact on any of the measured variables. Our data suggest that there is a significant physiological link between apoE and AbetaPP, as well as between apoE and tau in neurologically healthy, cognitively intact individuals.
authors.affiliation: Northwest Lipid Metabolism and Diabetes Research Laboratories, University of Washington School of Medicine, Seattle, WA 98109, USA.
authors.forename: Simona
authors.initials: S
authors.lastname: Vuletic
authors.forename: Ge
authors.initials: G
authors.lastname: Li
authors.forename: Elaine R
authors.initials: ER
authors.lastname: Peskind
authors.forename: Hal
authors.initials: H
authors.lastname: Kennedy
authors.forename: Santica M
authors.initials: SM
authors.lastname: Marcovina
authors.forename: James B
authors.initials: JB
authors.lastname: Leverenz
authors.forename: Eric C
authors.initials: EC
authors.lastname: Petrie
authors.forename: Virginia M-Y
authors.initials: VM
authors.lastname: Lee
authors.forename: Douglas
authors.initials: D
authors.lastname: Galasko
authors.forename: Gerard D
authors.initials: GD
authors.lastname: Schellenberg
authors.forename: John J
authors.initials: JJ
authors.lastname: Albers
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000378:metabolism; D016564:Amyloid beta-Protein Precursor / Q000134:cerebrospinal fluid*; D001057:Apolipoproteins E / Q000134:cerebrospinal fluid*; D015415:Biomarkers; D002784:Cholesterol / Q000134:cerebrospinal fluid; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009410:Nerve Degeneration / Q000134:cerebrospinal fluid / Q000378:metabolism; D009483:Neuropsychological Tests; D049294:Phospholipid Transfer Proteins / Q000134:cerebrospinal fluid; D012016:Reference Values; D012044:Regression Analysis; D055815:Young Adult; D016875:tau Proteins / Q000134:cerebrospinal fluid*
chemical_list: D016564:Amyloid beta-Protein Precursor; D001057:Apolipoproteins E; D015415:Biomarkers; D049294:Phospholipid Transfer Proteins; D016875:tau Proteins; D002784:Cholesterol