Search results for "plaques"
showing 10 items of 50 documents
The Role of Chemokines in Alzheimer's Disease
2019
Objective: The most common multifactorial neurodegenerative disorder occurring in old age is Alzheimer’s disease. The neuropathological hallmarks of that disorder are amyloid plaques with the presence of β -amyloid aggregates, intraneuronal tau protein tangles, and chronic inflammation. Brain cells such as microglia and astrocytes are inflammatory cells associated with Alzheimer’s disease and involved in the production of inflammatory mediators, such as cytokines and chemokines. Chemokines consist of a large family of protein mediators with low molecular weight, which able to control the migration and residence of all immune cells. In pathological conditions, such as Alzheimer’s disease, c…
Microglia in Alzheimer’s Disease: Activated, Dysfunctional or Degenerative
2018
Microglial activation has been considered a crucial player in the pathological process of multiple human neurodegenerative diseases. In some of these pathologies, such as Amyotrophic Lateral Sclerosis or Multiple Sclerosis, the immune system and microglial cells (as part of the cerebral immunity) play a central role. In other degenerative processes, such as Alzheimer’s disease (AD), the role of microglia is far to be elucidated. In this “mini-review” article, we briefly highlight our recent data comparing the microglial response between amyloidogenic transgenic models, such as APP/PS1 and AD patients. Since the AD pathology could display regional heterogeneity, we focus our work at the hipp…
ADAM10 in Alzheimer's disease: Pharmacological modulation by natural compounds and its role as a peripheral marker.
2019
Abstract Alzheimer’s disease (AD) represents a global burden in the economics of healthcare systems. Amyloid-β (Aβ) peptides are formed by amyloid-β precursor protein (AβPP) cleavage, which can be processed by two pathways. The cleavage by the α-secretase A Disintegrin And Metalloprotease 10 (ADAM10) releases the soluble portion (sAβPPα) and prevents senile plaques. This pathway remains largely unknown and ignored, mainly regarding pharmacological approaches that may act via different signaling cascades and thus stimulate non-amyloidogenic cleavage through ADAM10. This review emphasizes the effects of natural compounds on ADAM10 modulation, which eventuates in a neuroprotective mechanism. M…
Expression of endogenous mouse APP modulates β-amyloid deposition in hAPP-transgenic mice
2017
Amyloid-β (Aβ) deposition is one of the hallmarks of the amyloid hypothesis in Alzheimer’s disease (AD). Mouse models using APP-transgene overexpression to generate amyloid plaques have shown to model only certain parts of the disease. The extent to which the data from mice can be transferred to man remains controversial. Several studies have shown convincing treatment results in reducing Aβ and enhancing cognition in mice but failed totally in human. One model-dependent factor has so far been almost completely neglected: the endogenous expression of mouse APP and its effects on the transgenic models and the readout for therapeutic approaches. Here, we report that hAPP-transgenic models of …
Plasma phospholipid transfer protein (PLTP) modulates adaptive immune functions through alternation of T helper cell polarization
2016
International audience; Objective: Plasma phospholipid transfer protein (PLTP) is a key determinant of lipoprotein metabolism, and both animal and human studies converge to indicate that PLTP promotes atherogenesis and its thromboembolic complications. Moreover, it has recently been reported that PLTP modulates inflammation and immune responses. Although earlier studies from our group demonstrated that PLTP can modify macrophage activation, the implication of PLTP in the modulation of T-cell-mediated immune responses has never been investigated and was therefore addressed in the present study. Approach and results: In the present study, we demonstrated that PLTP deficiency in mice has a pro…
Autoantibodies Profile in Matching CSF and Serum from AD and aMCI patients: Potential Pathogenic Role and Link to Oxidative Damage.
2015
Abstract Alzheimer disease (AD) is the most common form of dementia among the elderly and is characterized by progressive loss of memory and cognition. Amyloid-s-peptide (As) forms senile plaques, which, together with hyperphosphorylated tau-based neurofibrillary tangles, are the hallmarks of AD neuropathology. Evidence support the involvement of immune system in AD progression and current concepts regarding its pathogenesis include the participation of inflammatory and autoimmune components in the neurodegenerative process. Pathologically, immune system components have been detected in the brain, cerebrospinal fluid (CSF) and in serum of AD subjects and their trend of variation correlates …
Mice are not Men: ADAM30 Findings Emphasize a Broader Look Towards Murine Alzheimer's Disease Models
2016
Due to the growing population of people at advanced age, the number of patients affected by Alzheimer's disease (AD) is increasing tremendously. In 2015 about 46.8 million people suffered from AD worldwide which is estimated to increase to 131.5 million by 2050. Brains of AD patients all show a common histopathology; they are marked by an atrophy and degeneration that is caused by a severe loss of neurons and synapses (Braak and Del Tredici, 2012). Moreover, so-called extracellular senile plaques that consist of predominantly amyloid β (Aβ) peptides can be detected in the grey matter where they surround neurons. Since generation of Aβ peptides is hypothesized to play a major role in AD path…
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…
Topographic heterogeneity of amyloid B-protein epitopes in brains with various forms of neuronal ceroid lipofuscinoses suggesting defective processin…
1990
To verify our hypothesis of defective protease inhibitor domains that are encoded by abnormal processing of amyloid precursor protein (APP) in brains of patients with neuronal ceroid lipofuscinoses (NCL), immunohistochemical and cytochemical studies were performed with monoclonal antibodies (mAbs) directed against various domains of APP. For the studies, 22 autopsy brains were used: 12 with different forms of NCL, and 10 control brains. The staining procedure for the avidin-biotin complex (ABC) technique and the postembedding gold-labelled procedure for electron microscopy (EM) were employed. Of all mAbs used for the study, only mAbs generated against amyloid B-protein bound to neural tissu…
Immune profiling of Alzheimer patients
2011
Abstract Alzheimer's disease (AD) is characterized by extracellular senile plaques in the brain, containing amyloid-β peptide (Aβ). We identify immunological differences between AD patients and age-matched controls greater than those related to age itself. The biggest differences were in the CD4 + rather than the CD8 + T cell compartment resulting in lower proportions of naive cells, more late-differentiated cells and higher percentages of activated CD4 + CD25 + T cells without a Treg phenotype in AD patients. Changes to CD4 + cells might be the result of chronic stimulation by Aβ present in the blood. These findings have implications for diagnosis and understanding the aetiology of the dis…