Merck
  • Home
  • Search Results
  • Folate and methylation status in relation to phosphorylated tau protein(181P) and beta-amyloid(1-42) in cerebrospinal fluid.

Folate and methylation status in relation to phosphorylated tau protein(181P) and beta-amyloid(1-42) in cerebrospinal fluid.

Clinical chemistry (2007-03-27)
Rima Obeid, Mariz Kasoha, Jean-Pierre Knapp, Panagiotis Kostopoulos, George Becker, Klaus Fassbender, Wolfgang Herrmann
ABSTRACT

Increased plasma total homocysteine (tHcy) is a risk factor for neurological diseases, but the underlying pathophysiology has not been adequately explained. We evaluated concentrations of tHcy, S-adenosyl homocysteine (SAH), S-adenosyl methionine (SAM), folate, and vitamin B(12) in cerebrospinal fluid (CSF) and plasma or serum from 182 patients with different neurological disorders. We measured concentrations of phosphorylated tau protein (P-tau)((181P)) and beta-amyloid(1-42) in the CSF. Aging was associated with higher concentrations of tHcy and SAH in the CSF, in addition to lower concentrations of CSF folate and lower SAM:SAH ratio. Concentrations of CSF SAH and CSF folate correlated significantly with those of P-tau (r = 0.46 and r = -0.28, respectively). Moreover, P-tau correlated negatively with SAM:SAH ratio (r = -0.40, P <0.001). The association between SAH and higher P-tau was observed in 3 age groups (<41, 41-60, and >60 years). CSF tHcy was predicted by concentrations of CSF cystathionine (beta = 0.478), folate (beta = -0.403), albumin (beta = 0.349), and age (beta = 0.298). tHcy concentration in the brain is related to age, B vitamins, and CSF albumin. Increase of CSF SAH is related to increased CSF P-tau; decreased degradation of P-tau might be a plausible explanation. Disturbed methyl group metabolism may be the link between hyperhomocysteinemia and neurodegeneration. Lowering tHcy and SAH might protect the brain by preventing P-tau accumulation.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
Titanium, wire, diam. 0.127 mm, 99.99% trace metals basis
Sigma-Aldrich
L-Glutathione reduced, Vetec, reagent grade, ≥98%
Sigma-Aldrich
Silicon, sputtering target, diam. × thickness 2.00 in. × 0.25 in., 99.999% trace metals basis
Sigma-Aldrich
L-(+)-Lactic acid, Vetec, reagent grade, 86%
Sigma-Aldrich
Nickel, sputtering target, diam. × thickness 2.00 in. × 0.25 in., 99.95% trace metals basis
Sigma-Aldrich
L-Glutathione oxidized, Vetec, reagent grade, ≥98%
Sigma-Aldrich
Silicon, wafer (single side polished), <100>, N-type, contains phosphorus as dopant, diam. × thickness 3 in. × 0.5 mm
Sigma-Aldrich
Silicon, wafer (single side polished), <111>, N-type, contains no dopant, diam. × thickness 3 in. × 0.5 mm
Sigma-Aldrich
Silicon, wafer, <111>, P-type, contains boron as dopant, diam. × thickness 2 in. × 0.3 mm
Sigma-Aldrich
Silicon, wafer (single side polished), contains phosphorus as dopant, <111>, N-type, diam. × thickness 2 in. × 0.5 mm
Sigma-Aldrich
Silicon, wafer (single side polished), <111>, N-type, contains no dopant, diam. × thickness 2 in. × 0.5 mm
Sigma-Aldrich
Silicon, wafer (single side polished), <100>, N-type, contains phosphorus as dopant, diam. × thickness 2 in. × 0.5 mm
Sigma-Aldrich
Silicon, wafer (single side polished), <100>, N-type, contains no dopant, diam. × thickness 3 in. × 0.5 mm
Sigma-Aldrich
Silicon, wafer (single side polished), <100>, P-type, contains boron as dopant, diam. × thickness 2 in. × 0.5 mm
Sigma-Aldrich
Silicon, wafer (single side polished), <100>, P-type, contains boron as dopant, diam. × thickness 3 in. × 0.5 mm
Sigma-Aldrich
Silicon, wafer (single side polished), <111>, P-type, contains boron as dopant, diam. × thickness 3 in. × 0.5 mm
Sigma-Aldrich
Silicon, wafer (single side polished), <100>, N-type, contains no dopant, diam. × thickness 2 in. × 0.5 mm
Sigma-Aldrich
Silicon, nanopowder, <100 nm particle size (TEM), ≥98% trace metals basis
Sigma-Aldrich
L-Cysteine, produced by Wacker Chemie AG, Burghausen, Germany, ≥98.0%
Sigma-Aldrich
Titanium, sputtering target, diam. × thickness 3.00 in. × 0.125 in., 99.995% trace metals basis
Supelco
L-Cysteine, certified reference material, TraceCERT®
Sigma-Aldrich
Copper, sputtering target, diam. × thickness 2.00 in. × 0.25 in., 99.95% trace metals basis
Sigma-Aldrich
Titanium, sputtering target, diam. × thickness 2.00 in. × 0.25 in., 99.995% trace metals basis
Sigma-Aldrich
L-Cysteine, Vetec, reagent grade, 97%
Sigma-Aldrich
Copper, nanopowder, 60-80 nm particle size (SAXS), ≥99.5% trace metals basis
Sigma-Aldrich
Copper, nanopowder, 40-60 nm particle size (SAXS), ≥99.5% trace metals basis
Sigma-Aldrich
cis-4,7,10,13,16,19-Docosahexaenoic acid, ≥98%
Sigma-Aldrich
DL-Homocysteine, ≥95% (titration)
Sigma-Aldrich
L-(+)-Lactic acid, ≥98%
Sigma-Aldrich
L-Glutathione oxidized, ≥98% (HPLC)