Read by QxMD icon Read


Misato Yoshikawa, Yoshiyuki Soeda, Makoto Michikawa, Osborne F X Almeida, Akihiko Takashima
Hippocampal hyperactivity, ascribed to amyloid β (Aβ)-induced imbalances in neural excitation and inhibition, is found in patients with mild cognitive impairment, a prodromal stage of Alzheimer's disease (AD). To better understand the relationship between hippocampal hyperactivity and the molecular triggers of behavioral impairments in AD, we used Mn-enhanced MRI (MEMRI) to assess neuronal activity after subjecting mice to a task requiring spatial learning and memory. Depletion of endogenous tau in an amyloid precursor protein (APP) transgenic (J20) mouse line was shown to ameliorate hippocampal hyperactivity in J20 animals, tau depletion failed to reverse memory deficits associated with APP/Aβ overproduction...
2018: Frontiers in Neuroscience
Xueying Wang, Ksenia V Kastanenka, Michal Arbel-Ornath, Caitlin Commins, Akira Kuzuya, Amanda J Lariviere, Grant A Krafft, Franz Hefti, Jasna Jerecic, Brian J Bacskai
Soluble amyloid β oligomers (AβOs) are widely recognized neurotoxins that trigger aberrant signaling in specific subsets of neurons, leading to accumulated neuronal damage and memory disorders in Alzheimer's disease (AD). One of the profound downstream consequences of AβO-triggered events is dysregulation of cytosolic calcium concentration ([Ca2+ ]i ), which has been implicated in synaptic failure, cytoskeletal abnormalities, and eventually neuronal death. We have developed an in vitro/in vivo drug screening assay to evaluate putative AβO-blocking candidates by measuring AβO-induced real-time changes in [Ca2+ ]i ...
March 15, 2018: Scientific Reports
Lisa K Gouwens, Mudar S Ismail, Victoria A Rogers, Nathan T Zeller, Evan C Garrad, Fatima S Amtashar, Nyasha J Makoni, David C Osborn, Michael R Nichols
Microvesicles (MVs) and exosomes comprise a class of cell-secreted particles termed extracellular vesicles (EVs). These cargo-holding vesicles mediate cell-to-cell communication and have recently been implicated in neurodegenerative diseases such as Alzheimer's disease (AD). The two types of EVs are distinguished by the mechanism of cell release and their size, with the smaller exosomes and the larger MVs ranging from 30 to 100 nm and 100 nm to 1 μm in diameter, respectively. MV numbers are increased in AD and appear to interact with amyloid-β peptide (Aβ), the primary protein component of the neuritic plaques in the AD brain...
March 15, 2018: ACS Chemical Neuroscience
Weijun Huang, Yujun Wang, Jiaming Li, Yanchun Zhang, Xiaodong Ma, Panhu Zhu, Yang Zhang
Twenty two novel genipin derivatives have been designed, synthesized and evaluated for their inhibitory activity against acetylcholinesterase (AChE). As a result, compound 13a bearing ligustrazine moiety displayed the most potent AChE inhibitory activity in this serieswith IC50 value of 218 nM. Besides, MTT assay was performed to investigate the neuroprotection of these compounds against PC12 cells injured by Amyloid β-protein 1-42 (Aβ1-42 ). Among them, 8a showed higher inhibition rate (%Inhibition = 22...
March 15, 2018: Chemical Biology & Drug Design
Esther M C van Leijsen, H Bea Kuiperij, Iris Kersten, Mayra I Bergkamp, Ingeborg W M van Uden, Hugo Vanderstichele, Erik Stoops, Jurgen A H R Claassen, Ewoud J van Dijk, Frank-Erik de Leeuw, Marcel M Verbeek
BACKGROUND AND PURPOSE: Cerebral small vessel disease (SVD) is a frequent pathology in aging and contributor to the development of dementia. Plasma Aβ (amyloid β) levels may be useful as early biomarker, but the role of plasma Aβ in SVD remains to be elucidated. We investigated the association of plasma Aβ levels with severity and progression of SVD markers. METHODS: We studied 487 participants from the RUN DMC study (Radboud University Nijmegen Diffusion Tensor and Magnetic Resonance Imaging Cohort) of whom 258 participants underwent 3 MRI assessments during 9 years...
March 14, 2018: Stroke; a Journal of Cerebral Circulation
Ariel A Valiente-Gabioud, Dietmar Riedel, Tiago F Outeiro, Mauricio A Menacho-Márquez, Christian Griesinger, Claudio O Fernández
The inherent tendency of proteins to convert from their native states into amyloid aggregates is associated with a range of human disorders, including Alzheimer's and Parkinson's diseases. In that sense, the use of small molecules as probes for the structural and toxic mechanism related to amyloid aggregation has become an active area of research. Compared with other compounds, the structural and molecular basis behind the inhibitory interaction of phthalocyanine tetrasulfonate (PcTS) with proteins such as αS and tau has been well established, contributing to a better understanding of the amyloid aggregation process in these proteins...
March 13, 2018: Biophysical Journal
Aurelio Vazquez de la Torre, Marina Gay, Sílvia Vilaprinyó-Pascual, Roberta Mazzucato, Montserrat Serra-Batiste, Marta Vilaseca, Natalia Carulla
Brain-derived amyloid-β (Aβ) dimers are associated with Alzheimer´s disease (AD). However, their covalent nature remains controversial. This feature is relevant, as a covalent cross-link would make brain-derived dimers (brain dimers) more synaptotoxic than Aβ monomers and would make them suitable candidates for biomarker development. To resolve this controversy, we here present a three-step approach. First, we validated a type of synthetic cross-linked Aβ (CL Aβ) dimers, obtained by means of the photo-induced cross-linking of unmodified proteins (PICUP) reaction, as well-defined mimics of putative brain CL Aβ dimers...
March 14, 2018: Analytical Chemistry
Jennifer Abbasi
No abstract text is available yet for this article.
March 13, 2018: JAMA: the Journal of the American Medical Association
Yi-Heng Tai, Yu-Yi Lin, Kai-Chen Wang, Chao-Lin Chang, Ru-Yin Chen, Chia-Chu Wu, Irene H Cheng
Alzheimer's disease (AD) is the most prevalent neurodegenerative disorder and is triggered via abnormal accumulation of amyloid-β peptide (Aβ). Aggregated Aβ is responsible for disrupting calcium homeostasis, inducing neuroinflammation, and promoting neurodegeneration. In this study, we generated curcuminoid submicron particle (CSP), which reduce the average size to ~60 nm in diameter. CSP had elevated the bioavailability in vivo and better neuroprotective effect against oligomeric Aβ than un-nanosized curcuminoids in vitro ...
February 13, 2018: Oncotarget
Itay Cohen, Si Naftaly, Efrat Ben-Zeev, Alexandra Hockla, Evette S Radisky, Niv Papo
High structural and sequence similarity within protein families can pose significant challenges to the development of selective inhibitors, especially towards proteolytic enzymes. Such enzymes usually belong to large families of closely similar proteases and may also hydrolyze, with different rates, protein or peptide-based inhibitors. To address this challenge, we employed a combinatorial yeast surface display library approach complemented with a novel pre-equilibrium, competitive screening strategy for facile assessment of the effects of multiple mutations on inhibitor association rates and binding specificity...
March 13, 2018: Biochemical Journal
N Khodaie, N Tajuddin, R M Mitchell, E J Neafsey, M A Collins
Preconditioning brain cultures with moderate concentrations of ethanol (EtOH) or trans-resveratrol (RES), key red wine constituents, can prevent amyloid-β (Aβ) neurotoxicity. Past studies have indicated that moderate EtOH activates synaptic N-methyl-D-aspartate receptors (NMDAR) that, in part, signal via protein kinase C (PKC) to increase protective antioxidant proteins such as peroxiredoxin-2 (Prx2). RES preconditioning also is reported to involve NMDAR and PKC. However, although moderate, the EtOH and RES concentrations used have been noticeably above circulating levels from two glasses of wine, a daily intake linked to reduced risk of cognitive decline among older social drinkers...
March 12, 2018: Neurotoxicity Research
Seokjo Kang, Jayoung Byun, Sung Min Son, Inhee Mook-Jung
Alzheimer's disease (AD) is often characterized by the impairment of mitochondrial function caused by excessive mitochondrial fragmentation. Thrombospondin-1 (TSP-1), which is primarily secreted from astrocytes in the central nervous system (CNS), has been suggested to play a role in synaptogenesis, spine morphology, and synaptic density of neurons. In this study, we investigate the protective role of TSP-1 in the recovery of mitochondrial morphology and function in amyloid β (Aβ)-treated mouse hippocampal neuroblastoma cells (HT22)...
December 2018: Cell Death Discovery
Frank Matthes, Moritz M Hettich, Judith Schilling, Diana Flores-Dominguez, Nelli Blank, Thomas Wiglenda, Alexander Buntru, Hanna Wolf, Stephanie Weber, Ina Vorberg, Alina Dagane, Gunnar Dittmar, Erich Wanker, Dan Ehninger, Sybille Krauss
Alzheimer's disease (AD) is characterized by two neuropathological hallmarks: senile plaques, which are composed of amyloid-β (Aβ) peptides, and neurofibrillary tangles, which are composed of hyperphosphorylated tau protein. Aβ peptides are derived from sequential proteolytic cleavage of the amyloid precursor protein (APP). In this study, we identified a so far unknown mode of regulation of APP protein synthesis involving the MID1 protein complex: MID1 binds to and regulates the translation of APP mRNA...
December 2018: Cell Death Discovery
J Chung, G Phukan, D Vergote, A Mohamed, M Maulik, M Stahn, R J Andrew, G Thinakaran, E Posse de Chaves, S Kar
Amyloid β (Aβ) peptide derived from amyloid precursor protein (APP) plays a critical role in the development of Alzheimer's disease. Current evidence indicates that altered levels/subcellular distribution of cholesterol can regulate Aβ production/clearance, but it remains unclear how cholesterol sequestration within the endosomal-lysosomal (EL) system can influence APP metabolism. Thus, we evaluated the effects of U18666A, which triggers cholesterol redistribution within EL system, on mouse N2a cells expressing different levels of APP in the presence or absence of extracellular cholesterol/lipids provided by fetal bovine serum (FBS)...
March 12, 2018: Molecular and Cellular Biology
Kyoung A Jhang, Jin-Sun Park, Hee-Sun Kim, Young Hae Chong
BACKGROUND: Mer tyrosine kinase (MerTK) activity necessary for amyloid-stimulated phagocytosis strongly implicates that MerTK dysregulation might contribute to chronic inflammation implicated in Alzheimer's disease (AD) pathology. However, the precise mechanism involved in the regulation of MerTK expression by amyloid-β (Aβ) in proinflammatory environment has not yet been ascertained. METHODS: The objective of this study was to determine the underlying mechanism involved in Aβ-mediated decrease in MerTK expression through Aβ-mediated regulation of MerTK expression and its modulation by sulforaphane in human THP-1 macrophages challenged with Aβ1-42...
March 12, 2018: Journal of Neuroinflammation
Lena L Law, Rachael N Rol, Stephanie A Schultz, Ryan J Dougherty, Dorothy F Edwards, Rebecca L Koscik, Catherine L Gallagher, Cynthia M Carlsson, Barbara B Bendlin, Henrik Zetterberg, Kaj Blennow, Sanjay Asthana, Mark A Sager, Bruce P Hermann, Sterling C Johnson, Dane B Cook, Ozioma C Okonkwo
Introduction: Alzheimer's disease (AD) is characterized by the presence of amyloid β (Aβ) plaques, neurofibrillary tangles, and neurodegeneration, evidence of which may be detected in vivo via cerebrospinal fluid (CSF) sampling. Physical activity (PA) has emerged as a possible modifier of these AD-related pathological changes. Consequently, the aim of this study was to cross-sectionally examine the relationship between objectively measured PA and CSF levels of Aβ42 and tau in asymptomatic late-middle-aged adults at risk for AD...
2018: Alzheimer's & Dementia: Diagnosis, Assessment & Disease Monitoring
Katelyn L Arnemann, Franziska Stöber, Sharada Narayan, Gil D Rabinovici, William J Jagust
Metabolic brain networks can provide insight into the network processes underlying progression from healthy aging to Alzheimer's disease. We explore the effect of two Alzheimer's disease risk factors, amyloid-β and ApoE ε4 genotype, on metabolic brain networks in cognitively normal older adults (N = 64, ages 69-89) compared to young adults (N = 17, ages 20-30) and patients with Alzheimer's disease (N = 22, ages 69-89). Subjects underwent MRI and PET imaging of metabolism (FDG) and amyloid-β (PIB). Normal older adults were divided into four subgroups based on amyloid-β and ApoE genotype...
2018: NeuroImage: Clinical
Chia-Liang Tsai, Jozef Ukropec, Barbara Ukropcová, Ming-Chyi Pai
Although exercise is an effective way to decrease the risk of developing Alzheimer's disease, the biological basis for such benefits from the different exercise modes remains elusive. The present study thus aimed (i) to investigate the effects of acute aerobic or resistance exercise on neurocognitive performances and molecular markers when performing a cognitive task involving executive functioning in older adults with amnestic mild cognitive impairment (aMCI), and (ii) to explore relationships of acute exercise-induced neurocognitive changes with changes in circulating levels of neuroprotective growth factors (e...
2018: NeuroImage: Clinical
Vijayaraghavan Rangachari, Dexter N Dean, Pratip Rana, Ashwin Vaidya, Preetam Ghosh
Self-templating propagation of protein aggregate conformations is increasingly becoming a significant factor in many neurological diseases. In Alzheimer disease (AD), intrinsically disordered amyloid-β (Aβ) peptides undergo aggregation that is sensitive to environmental conditions. High-molecular weight aggregates of Aβ that form insoluble fibrils are deposited as senile plaques in AD brains. However, low-molecular weight aggregates called soluble oligomers are known to be the primary toxic agents responsible for neuronal dysfunction...
March 8, 2018: Biochimica et Biophysica Acta
Daniela Mendes, Maria Manuel Oliveira, Paula I Moreira, João Coutinho, Fernando M Nunes, David M Pereira, Patrícia Valentão, Paula B Andrade, Romeu A Videira
The development of effective medicines to break or delay the progressive brain degeneration underlying cognitive decline and dementia that characterize Alzheimer's disease (AD) is one of the greatest challenges of our time. In the present work, a selective pool of polyphenols, obtained from the white wine by adsorption to polyvinylpyrrolidone polymer (PVPP), was used to prepare a polyphenols-enriched diet, supplementing the drinking water with 100 mg/L (expressed as gallic acid equivalent) of wine polyphenolic extract...
February 10, 2018: Journal of Nutritional Biochemistry
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"