Search results for "alzheimer’s disease"
showing 10 items of 120 documents
Early Cognitive Training Rescues Remote Spatial Memory but Reduces Cognitive Flexibility in Alzheimer’s Disease Mice
2020
Background: Spatial memory dysfunction has been demonstrated in mouse models of Alzheimer’s disease (AD) which is consistent with the clinical finding that the early signature of AD includes difficulties in the formation and/or storage of a memory. A stored memory—a long term memory—can be modulated via process called as memory retrieval that can either lead toward memory reconsolidation or even memory extinction. Objective: We aim to shed light on the fate of the spatial memory during memory reactivation and memory extinction using a water maze task. Methods: In Set-up I, we trained 3-month-old mice (wild-type mice and mice with cerebral β-amyloidosis) and assessed the fate of remote memor…
Semaphorins in Adult Nervous System Plasticity and Disease
2021
Semaphorins, originally discovered as guidance cues for developing axons, are involved in many processes that shape the nervous system during development, from neuronal proliferation and migration to neuritogenesis and synapse formation. Interestingly, the expression of many Semaphorins persists after development. For instance, Semaphorin 3A is a component of perineuronal nets, the extracellular matrix structures enwrapping certain types of neurons in the adult CNS, which contribute to the closure of the critical period for plasticity. Semaphorin 3G and 4C play a crucial role in the control of adult hippocampal connectivity and memory processes, and Semaphorin 5A and 7A regulate adult neuro…
Circulating Molecular Chaperones in Subjects with Amnestic Mild Cognitive Impairment and Alzheimer’s Disease: Data from the Zabùt Aging Project
2022
Molecular chaperones play essential roles in many processes such as cell differentiation, tissue homeostasis, and organ remodeling. Recent data indicate that chaperones can act as cytoprotectants for brain cells during the progression of neurodegenerative diseases, including Alzheimer’s disease (AD). However, very few data on the levels of chaperones in dementia, including its prodromal phases, have been reported. In this study, we used biological samples and epidemiological data collected during the Zabùt Aging Project (a prospective, community-based, cohort study of normal/pathological aging conducted in Sicily, Italy, with a follow-up of ten years) to determine if there is an association…
Identification of Phlogacantholide C as a Novel ADAM10 Enhancer from Traditional Chinese Medicinal Plants
2016
Background: Alzheimer’s disease is one of the most prevalent dementias in the elderly population with increasing numbers of patients. One pivotal hallmark of this disorder is the deposition of protein aggregates stemming from neurotoxic amyloid-beta peptides. Synthesis of those peptides has been efficiently prevented in AD model mice by activation of an enzyme called alpha-secretase. Therefore, drugs with the capability to increase the expression of this enzyme, named ADAM10, have been suggested as a valuable therapeutic medication. Methods: We investigated 69 substances from a drug library derived from traditional Chinese medicine by luciferase reporter assay in human neuronal cells for th…
Metal Ions and Metal Complexes in Alzheimer's Disease.
2015
Background: Alzheimer’s disease (AD) is the most common form of dementia that seriously affects daily life. Even if AD pathogenesis is still subject of debate, it is generally accepted that cerebral cortex plaques formed by aggregated amyloid-β (Aβ) peptides can be considered a characteristic pathological hallmark. It is well known that metal ions play an important role in the aggregation process of Aβ. Methods: This review focuses on the anti-Aβ aggregation activity of chelating ligands as well as on the use of metal complexes as diagnostic probes and as potential drugs. Conclusion: While chelating agents, such as curcumin or flavonoid derivatives, are currently used to capture metal ions …
Structure and Synaptic Function of Metal Binding to the Amyloid Precursor Protein and its Proteolytic Fragments
2017
Alzheimer’s disease (AD) is ultimately linked to the Amyloid Precursor Protein (APP). However, current research reveals an important synaptic function of APP and APP-like proteins (APLP1 and 2). In this context various neurotrophic and neuroprotective functions have been reported for the APP proteolytic fragments sAPPα, sAPPβ, and the monomeric amyloid-beta peptide (Aβ). APP is a metalloprotein and binds copper and zinc ions. Synaptic activity correlates with a release of these ions into the synaptic cleft and dysregulation of their homeostasis is linked to different neurodegenerative diseases. Metal binding to APP or its fragments affects its structure and its proteolytic cleavage and ther…
Changes in Serine Racemase-Dependent Modulation of NMDA Receptor: Impact on Physiological and Pathological Brain Aging
2018
International audience; The N-methyl-D-Aspartate glutamate receptors (NMDARs) are pivotal for the functional and morphological plasticity that are required in neuronal networks for efficient brain activities and notably for cognitive-related abilities. Because NMDARs are heterogeneous in subunit composition and associated with multiple functional regulatory sites, their efficacy is under the tonic influence of numerous allosteric modulations, whose dysfunction generally represents the first step generating pathological states. Among the enzymatic candidates, serine racemase (SR) has recently gathered an increasing interest considering that it tightly regulates the production of D-serine, an…
Physiological Functions of the β-Site Amyloid Precursor Protein Cleaving Enzyme 1 and 2
2017
BACE1 was discovered as the β-secretase for initiating the cleavage of amyloid precursor protein (APP) at the β-secretase site, while its close homology BACE2 cleaves APP within the β-amyloid (Aβ) domain region and shows distinct cleavage preferences in vivo. Inhibition of BACE1 proteolytic activity has been confirmed to decrease Aβ generation and amyloid deposition, and thus specific inhibition of BACE1 by small molecules is a current focus for Alzheimer’s disease therapy. While BACE1 inhibitors are being tested in advanced clinical trials, knowledge regarding the properties and physiological functions of BACE is highly important and this review summarizes advancements in BACE1 research ov…
Functions and Therapeutic Potential of Extracellular Hsp60, Hsp70, and Hsp90 in Neuroinflammatory Disorders
2021
Neuroinflammation is implicated in central nervous system (CNS) diseases, but the molecular mechanisms involved are poorly understood. Progress may be accelerated by developing a comprehensive view of the pathogenesis of CNS disorders, including the immune and the chaperone systems (IS and CS). The latter consists of the molecular chaperones; cochaperones; and chaperone cofactors, interactors, and receptors of an organism and its main collaborators in maintaining protein homeostasis (canonical function) are the ubiquitin–proteasome system and chaperone-mediated autophagy. The CS has also noncanonical functions, for instance, modulation of the IS with induction of proinflammatory cytokines. …
Dysregulation of C-X-C motif ligand 10 during aging and association with cognitive performance
2017
International audience; Chronic low-grade inflammation during aging (inflammaging) is associated with cognitive decline and neurodegeneration; however, the mechanisms underlying inflammaging are unclear. We studied a population (n = 361) of healthy young and old adults from the MyoAge cohort. Peripheral levels of C-X-C motif chemokine ligand 10 (CXCL10) was found to be higher in older adults, compared with young, and negatively associated with working memory performance. This coincided with an age-related reduction in blood DNA methylation at specific CpGs within the CXCL10 gene promoter. In vitro analysis supported the role of DNA methylation in regulating CXCL10 transcription. A polymorph…