Search results for "Alzheimers-Disease"
showing 10 items of 17 documents
The Early Indicators of Functional Decrease in Mild Cognitive Impairment
2016
OBJECTIVES: Motor deficiency is associated with cognitive frailty in patients with Mild Cognitive Impairments (MCI). In this study we aimed to test the integrity of the muscle synergy involved in an arm-pointing movement in MCI patients, non-impaired functionally. Thus, we were able to test the hypothesis that early motor indicators exist in this population at a preclinical level. METHODS: The electromyographic signals were collected for 11 muscles in 3 groups: Young Adults (YA), Aged Adults (AA), and MCI patients. The AA and MCI groups presented the same functional status. Each subject performed twenty arm-pointing movements from a standing position. RESULTS: The main differences were (1) …
A novel microglial subset plays a key role in myelinogenesis in developing brain.
2017
Microglia are resident macrophages of the central nervous system that contribute to homeostasis and neuroinflammation. Although known to play an important role in brain development, their exact function has not been fully described. Here, we show that in contrast to healthy adult and inflammation-activated cells, neonatal microglia show a unique myelinogenic and neurogenic phenotype. A CD11c(+) microglial subset that predominates in primary myelinating areas of the developing brain expresses genes for neuronal and glial survival, migration, and differentiation. These cells are the major source of insulin-like growth factor 1, and its selective depletion from CD11c(+) microglia leads to impa…
Sphingolipids and Inositol Phosphates Regulate the Tau Protein Phosphorylation Status in Humanized Yeast
2020
Hyperphosphorylation of protein tau is a hallmark of Alzheimer’s disease (AD). Changes in energy and lipid metabolism have been correlated with the late onset of this neurological disorder. However, it is uncertain if metabolic dysregulation is a consequence of AD or one of the initiating factors of AD pathophysiology. Also, it is unclear whether variations in lipid metabolism regulate the phosphorylation state of tau. Here, we show that in humanized yeast, tau hyperphosphorylation is stimulated by glucose starvation in coincidence with the downregulation of Pho85, the yeast ortholog of CDK5. Changes in inositol phosphate (IP) signaling, which has a central role in energy metabolism, altere…
Negatively Charged Gangliosides Promote Membrane Association of Amphipathic Neurotransmitters
2018
Lipophilic neurotransmitters (NTs) such as dopamine are chemical messengers enabling neurotransmission by adhering onto the extracellular surface of the post-synaptic membrane in a synapse, followed by binding to their receptors. Previous studies have shown that the strength of the NT-membrane association is dependent on the lipid composition of the membrane. Negatively charged lipids such as phosphatidylserine, phosphatidylglycerol, and phosphatidic acid have been indicated to promote NT-membrane binding, however these anionic lipids reside almost exclusively in the intracellular leaflet of the post-synaptic membrane instead of the extracellular leaflet facing the synaptic cleft. Meanwhile…
Kinematic analysis of motor strategies in frail aged adults during the Timed Up and Go: how to spot the motor frailty?
2015
Asma Hassani,1 Alexandre Kubicki,2,3 Vincent Brost,1 France Mourey,2,4 Fan Yang1 1Laboratoire LE2I CNRS 6306, Université de Bourgogne, Dijon, France; 2Institut National de la Santé et de la Recherche Médicale (INSERM), Cognition Action et Plasticité Sensori-Motrice, Campus Universitaire, Université de Bourgogne, Dijon, France; 3Centre Hospitalier Universitaire de Dijon, Hôpital de Champmaillot, Dijon, France; 4Faculté de Médecine, Université de Bourgogne, Dijon, France Objective: The purpose of this work was to analyze and compare the movement kinematics of sit-to-stand (STS) and back-to-sit (B…
Lack of genetic association of neutral endopeptidase (NEP) with complex regional pain syndrome (CRPS)
2010
Complex regional pain syndrome (CRPS) is a condition that is characterized by severe pain and exaggerated neurogenic inflammation, which may develop after injury or surgery. Neurogenic inflammation is mediated by neuropeptides, such as calcitonin gene-related peptide (CGRP) and substance P (SP) that are released from nociceptors. Genetic factors may play a role in CRPS as was suggested by the occurrence of familial cases and several genetic association studies investigating mainly the human leukocyte antigen (HLA) system. Here we investigated the role of neutral endopeptidase (NEP), a key enzyme in neuropeptide catabolism. NEP dysfunction resulting in reduced inactivation of neuropeptides m…
Monitoring cognitive changes: Psychometric properties of six cognitive tests
2004
Objectives. Repeated neuropsychological assessments are often used to monitor change in cognitive functioning over time. Thus, knowledge about the reliability and stability of neuropsychological tests and the effects of age and IQ is of paramount importance. In this study we document, for six cognitive tests: test-retest reliabilities, practice effects, reliable change (RC) indices corrected for practice, and the impact of premorbid IQ and age. Design. A sample of 188 normal adults (aged 40-70 years) were administered, on two occasions, one or more of the following tests: the Graded Naming Test (GNT), the Silhouettes Test, two tests of verbal fluency, the Modified Wisconsin Card Sorting Tes…
Corpus callosum area in patients with bipolar disorder with and without psychotic features: an international multicentre study
2015
Background Previous studies have reported MRI abnormalities of the corpus callosum (CC) in patients with bipolar disorder (BD), although only a few studies have directly compared callosal areas in psychotic versus nonpsychotic patients with this disorder. We sought to compare regional callosal areas in a large international multicentre sample of patients with BD and healthy controls. Methods We analyzed anatomic T-1 MRI data of patients with BD-I and healthy controls recruited from 4 sites (France, Germany, Ireland and the United States). We obtained the mid-sagittal areas of 7 CC subregions using an automatic CC delineation. Differences in regional callosal areas between patients and contr…
The relationship between cortisol and cognitive function in healthy older people: The moderating role of Apolipoprotein E polymorphism.
2018
The Apolipoprotein E4 (ApoE-epsilon 4) allele has been suggested as the main risk factor for late onset Alzheimer's disease (AD), whereas the ApoE-epsilon 2 allele has been proposed as a protective factor. These proposals have increased the interest in the effect of the ApoE genotype in healthy people. Additionally, high cortisol levels have been related to negative effects on cognition. However, few studies have investigated the relationship between cognitive performance and cortisol, taking into account the different ApoE alleles. For this reason, the aim of this study was to evaluate different cognitive domains (declarative and working memory, attention, and executive function) and their…
Entrapment of A Beta 1-40 peptide in unstructured aggregates
2012
Recognizing the complexity of the fibrillogenesis process provides a solid ground for the development of therapeutic strategies aimed at preventing or inhibiting protein-protein aggregation. Under this perspective, it is meaningful to identify the possible aggregation pathways and their relative products. We found that Aβ-peptide dissolved in a pH 7.4 solution at small peptide concentration and low ionic strength forms globular aggregates without typical amyloid β-conformation. ThT binding kinetics was used to monitor aggregate formation. Circular dichroism spectroscopy, AFM imaging, static and dynamic light scattering were used for structural and morphological characterization of the aggre…