Selenoprotein P Concentrations in the Cerebrospinal Fluid and Serum of Individuals Affected by Amyotrophic Lateral Sclerosis, Mild Cognitive Impairment and Alzheimer’s Dementia

Abstract

Selenoprotein P, a selenium-transporter protein, has been hypothesized to play a role in the etiology of neurodegenerative diseases such as amyotrophic lateral sclerosis (ALS) and Alzheimer’s dementia (AD). However, data in humans are scarce and largely confined to autoptic samples. In this case–control study, we determined selenoprotein P concentrations in both the cerebrospinal fluid (CSF) and the serum of 50 individuals diagnosed with ALS, 30 with AD, 54 with mild cognitive impairment (MCI) and of 30 controls, using sandwich enzyme-linked immunosorbent assay (ELISA) methods. We found a positive and generally linear association between CSF and serum selenoprotein P concentrations in all groups. CSF selenoprotein P and biomarkers of neurodegeneration were positively associated in AD, while for MCI, we found an inverted-U-shaped relation. CSF selenoprotein P concentrations were higher in AD and MCI than in ALS and controls, while in serum, the highest concentrations were found in MCI and ALS. Logistic and cubic spline regression analyses showed an inverse association between CSF selenoprotein P levels and ALS risk, and a positive association for AD risk, while an inverted-U-shaped relation with MCI risk emerged. Conversely, serum selenoprotein P concentrations were positively associated with risk of all conditions but only in their lower range. Overall, these findings indicate some abnormalities of selenoprotein P concentrations in both the central nervous system and blood associated with ALS and neurocognitive disorders, though in different directions. These alterations may reflect either phenomena of etiologic relevance or disease-induced alterations of nutritional and metabolic status.

Multi-omics profiling of CSF from spinal muscular atrophy type 3 patients after nusinersen treatment: a 2-year follow-up multicenter retrospective study

“…However, several pieces of evidence suggest that it is also relevant for normal brain function [ 55 ]. In addition, low CSF concentrations of selenoprotein P-bound selenium have been associated with increased risk of amyotrophic lateral sclerosis [ 56 , 57 ], a sporadic adulthood onset motor neuron disorder. Consistently, we found increased CSF concentrations in SMA patients after nusinersen administration.…”

Organic selenocompounds: are they the panacea for human illnesses?

“…81,[86][87][88][89] The optimum blood Se levels (70 and 130 mg L À1 ) were determined by Rea et al 90 and Thomson et al 91,92 using the blood GPX activity as the biomarker of the Se dietary effect. However, the maximization of selenoprotein synthesis has been recently questioned by Vinceti et al, 93,94 particularly given the growing epidemiological data demonstrating an association between some selenoproteins and chronic diseases. The recommended dietary allowance is 55 mg Se day À1 for individuals above 14 years of age with a tolerable upper intake limit of 400 mg Se day À1 , 82,95,96 and the toxic dose was established as greater as 700 mg Se day À1 for adults.…”

Quartic autocatalysis on horizontal surfaces with an asymmetric concentration: water-based ternary-hybrid nanofluid carrying titania, copper, and alumina nanoparticles

“…The importance of understanding the concentration of fluid substances is inevitable in almost all branches of science. For instance, in a study on the cerebrospinal fluid, Urbano et al [1] studied the situation when there is an increasing 10-unit selenoprotein P concentration. In a study on monitoring antibiotic use in animals by Gajda et al [2], the concentrations of lincomycin and tiamulin were relatively high.…”