Beta-amyloid (Aβ) accumulation, one of the most important pathogenic traits of Alzheimer's disease (AD), has been reported to induce neurotoxicity in vitro as well as in vivo. Honokiol, isolated from the bark of Magnolia officinalis, has neuroprotective effects in different models of AD in vivo and in vitro. However, the exact mechanism for its neuroprotective effect is not well understood. The...

Amyloid-β (Aβ)-containing extracellular plaques and hyperphosphorylated tau-loaded intracellular neurofibrillary tangles are neuropathological hallmarks of Alzheimer's disease (AD). Although Aβ exerts neuropathogenic activity through tau, the mechanistic link between Aβ and tau pathology remains unknown. Here, we showed that the FcγRIIb-SHIP2 axis is critical in Aβ1-42-induced tau pathology. Fc...

Alzheimer’s disease (AD) is an age-related neurodegenerative disease and is clinically characterized by cognitive impairment, memory loss, and personality disorder. Oligomers of amyloid beta-peptides (Aβ) and enhanced oxidative stress in senile plaques are prevalent pathologic hallmarks of AD. In this study, we detected the behavioral performance of Lycium ruthenicum Murray anthocyanin (LRA) -t...

Resveratrol, a natural polyphenol found in red wine, has wide spectrum of pharmacological properties including antioxidative and antiaging activities. Beta amyloid peptides (Aβ) are known to involve cognitive impairment, neuroinflammatory and apoptotic processes in Alzheimer's disease (AD). Activation of cAMP and/or cGMP activities can improve memory performance and decrease the neuroinflammati...

The objective of this study was to investigate the effects of modulating brain amyloid-β (Aβ) levels at different stages of amyloid pathology on synaptic function, inflammatory cell changes and hippocampal neurogenesis, i.e. processes perturbed in Alzheimer's disease (AD). Young (4- to 6-month-old) and older (15- to 18-month-old) APP(SWE) transgenic (Tg2576) mice were treated with the AD candid...

We investigated the neuropharmacological effects of the methanolic extract from Lactuca capensis Thunb. leaves (100 and 200 mg/kg) for 21 days on memory impairment in an Alzheimer's disease (AD) rat model produced by direct intraventricular delivery of amyloid-β1-42 (Aβ1-42). Behavioural assays such as Y-maze and radial arm maze test were used for assessing memory performance. Aβ1-42 decreased ...

Oxidative stress is implicated in the pathogenesis and progression of Alzheimer's disease (AD) and its earlier stage, amnestic mild cognitive impairment (aMCI). One source of oxidative stress in AD and aMCI brains is that associated with amyloid-β peptide, Aβ1-42 oligomers. Our laboratory first showed in AD elevated oxidative stress occurred in brain regions rich in Aβ1-42, but not in Aβ1-42-po...

Depending upon the stimulus, neuronal cell death can either be triggered from the cell body (soma) or the axon. We investigated the origin of the degeneration signal in amyloid β (Aβ) induced neuronal cell death in cultured in vitro hippocampal neurons. We discovered that Aβ1-42 toxicity-induced axon degeneration precedes cell death in hippocampal neurons. Overexpression of Bcl-xl inhibited bot...

Thermodynamic properties of complexes of Congo Red (CR) dye with amyloid  (A) peptides were studied by both absorption spectroscopy and isothermal titration calorimetry (ITC). Based on the absorption spectrum for the formation of CR-Aβ complexes in phosphate buffered saline solution (pH 7.4), van’t Hoff plots over a temperature range of 10oC to 70oC were created for CR-Aβ1-40, -Aβ12-28, and -...

Alzheimer's disease is a neurodegenerative disorder linked to oligomerization and fibrillization of amyloid β peptides, with Aβ1-42 being the most aggregative and neurotoxic one. We report herein the synthesis and conformational analysis of Aβ1-42-amyloid related β-hairpin peptidomimetics, built on a piperidine-pyrrolidine semi rigid β-turn inducer and bearing two small recognition peptide sequ...