Search results for "amyloid"
showing 10 items of 494 documents
ADAM-10 over-expression increases cortical synaptogenesis.
2006
Cortical cholinergic, glutamatergic and GABAergic terminals become upregulated during early stages of the transgenic amyloid pathology. Abundant evidence suggests that sAPP alpha, the product of the non-amyloidogenic alpha-secretase pathway, is neurotrophic both in vitro and when exogenously applied in vivo. The disintegrin metalloprotease ADAM-10 has been shown to have alpha-secretase activity in vivo. To determine whether sAPP alpha has an endogenous biological influence on cortical presynaptic boutons in vivo, we quantified cortical cholinergic, glutamatergic and GABAergic presynaptic bouton densities in either ADAM-10 moderate expressing (ADAM-10 mo) transgenic mice, which moderately ov…
Design, Synthesis, and Biological Evaluation of Novel Fluorinated Ethanolamines
2011
The preparation of novel fluorinated allylamines and their use as key fragments for the stereoselective synthesis of hydroxyethyl secondary amine (HEA)-type peptidomimetics is described. Our strategy employs chiral sulfinyl imines as synthesis intermediates, by treatment of hemiaminal precursors with two equivalents of vinylmagnesium bromide. The subsequent oxidation of the allylic amines to the corresponding epoxides was achieved by treatment with methyl(trifluoromethyl)dioxirane. Finally, epoxide ring opening with a range of nitrogen nucleophiles provided a library of HEA-derived peptidomimetics with a phenyldifluoromethylene moiety. The biological evaluation of these derivatives revealed…
CHARACTERIZATION OF THE SYNAPTIC PROTEOME IN NON-DEMENTED SUBJECTS WITH ALZHEIMER’S NEUROPATHOLOGY
Some individuals, here refereed to as Non-Demented with Alzheimer’s Neuropathology (NDAN), retain their congitive function despite the presence of amyloid plaques and tau tangles typical of symptomatic Alzheimer’s Disease (AD). In NDAN, unlike AD, toxic amyloid beta oligomers do not localize to the postsynaptic densities (PSDs). Synaptic resistance to amyloid beta in NDAN may thus enable these individuals to remain cognitively intact despite the AD-like pathology. The mechanim(s) responsible for this resistance remains unresolved and understanding such protective biological processes could reveal novel targets for the development of effective treatments for AD. The current work describes th…
SYNTHESIS AND EVALUATION OF CURCUMIN ANALOGUES AS NEURO-PROTECTIVE AGENTS FOR THE ALZHEIMER'S DISEASE
2013
The Alzheimer's disease (AD) is the most common form of senile dementia.1 The most important role in AD is played by the aggregation process of beta-amyloid peptide (Aß), responsible for the cytotoxic effects.2 In this context, the purpose of this study was to synthesize new dicarbonyl compounds 1 structurally related to curcumin3, with anti-aggregation activity against Aß.Parallel studies involve the synthesis of heterocyclic-based curcumin-like molecules that are currently under investigation by means of in silico protocols in order to rationalize the ligand-biological target interactions.
Targeting Alzheimer’s disease with multimodal polypeptide-based nanoconjugates
2021
LRP1-targeted St-Cl–polyglutamate conjugates as multivalent neuroprotective/neurotrophic therapeutics for Alzheimer’s disease.
Biomarkers Related to Synaptic Dysfunction to Discriminate Alzheimer’s Disease from Other Neurological Disorders
2022
Recently, the synaptic proteins neurogranin (Ng) and α-synuclein (α-Syn) have attracted scientific interest as potential biomarkers for synaptic dysfunction in neurodegenerative diseases. In this study, we measured the CSF Ng and α-Syn concentrations in patients affected by AD (n = 69), non-AD neurodegenerative disorders (n-AD = 50) and non-degenerative disorders (n-ND, n = 98). The concentrations of CSF Ng and α-Syn were significantly higher in AD than in n-AD and n-ND. Moreover, the Aβ42/Ng and Aβ42/α-Syn ratios showed statistically significant differences between groups and discriminated AD patients from n-AD patients, better than Ng or α-Syn…
Amyloid Fibrils Formation of Concanavalin A at Basic pH
2011
Mechanisms of partial unfolding and aggregation of proteins are of extreme interest in view of the fact that several human pathologies are characterized by the formation and deposition of protein-insoluble material, mainly composed of amyloid fibrils. Here we report on an experimental study on the heat-induced aggregation mechanisms, at basic pH, of concanavalin A (ConA), used as a model system. Thioflavin T (ThT) fluorescence and multiangle light scattering allowed us to detect different intertwined steps in the formation of ConA aggregates. In particular, the ThT fluorescence increase, observed in the first phase of aggregation, reveals the formation of intermolecular β-sheet structure wh…
Therapy of ATTR Cardiac Amyloidosis: Current Indications
2023
Transthyretin cardiac amyloidosis is a restrictive cardiomyopathy caused by extracellular deposition in the heart of amyloid fibrils derived from plasma transthyretin (ATTR), either in its hereditary (ATTRh) or acquired (ATTRwt) forms. Cardiac amyloidosis has a very poor prognosis if therapy is not started promptly. Therefore, it is very important to recognize cardiac amyloidosis early in order to immediately start a treatment capable of modifying the prognosis. Treatment of cardiac amyloidosis is not easy, often requiring a multidisciplinary team. New RNA-interfering drugs (such as patisiran) have been devised and are effective in the treatment of ATTRh amyloidosis. Tafamidis (a stabilizer…
Familial Amyloid Polyneuropathy
2013
Familial amyloid polyneuropathy (FAP; also known as familiar amyloidosis and hereditary amyloidosis) is an autosomal dominant inherited disease due to mutations of the transthyretin (TTR) gene coding for the corresponding protein, consisting of 127 amino acids. The gene is located on chromosome 18q. More than 100 different mutations are known. Other mutant precursor proteins produced in the liver, such as apolipoprotein I and II, lysozyme and fibrinogen Aα, may be of etiological importance as well. Amyloidogenic mutations of the TTR gene lead to decreased stability of the corresponding protein and subsequently to extracellular deposition of amyloid in several tissues (peripheral and autonom…