scholarly journals Postsynaptic dysfunction is associated with spatial and object recognition memory loss in a natural model of Alzheimer's disease

2012 ◽  
Vol 109 (34) ◽  
pp. 13835-13840 ◽  
Author(s):  
A. O. Ardiles ◽  
C. C. Tapia-Rojas ◽  
M. Mandal ◽  
F. Alexandre ◽  
A. Kirkwood ◽  
...  
2021 ◽  
Vol 12 ◽  
Author(s):  
Chihiro Tohda ◽  
Chisato Kogure ◽  
Kaori Nomoto ◽  
Andreia de Toledo ◽  
Ximeng Yang ◽  
...  

We investigated the effects of a heptapeptide, GPPGPAG, on memory improvement and neuritic regeneration in Alzheimer’s disease models to evaluate its potency as a new anti-Alzheimer’s disease (AD) therapy. The anti-AD effects of GPPGPAG were evaluated in Aβ-treated cortical neurons and 5XFAD, a mouse model of AD. Exposure of cortical neurons to Aβ25-35 for 3 days resulted in atrophy of axons and dendrites. Treatment with GPPGPAG improved the dendritic atrophy of Aβ-treated cortical neurons, but not axonal atrophy. Postsynaptic and presynaptic densities under Aβ1-42 exposure were increased by GPPGPAG post treatment. Oral administration of GPPGPAG to 5XFAD mice for 15 days improved significantly object recognition memory and dendritic density. Direct infusion of GPPGPAG into the lateral ventricle of 5XFAD mice for 28 days improved object recognition memory. Following oral administration of GPPGPAG in mice, the undigested heptapeptide was detected in the plasma and cerebral cortex. Analysis of target protein of GPPGPAG in neurons by DARTS method identified 14-3-3ε as a bound protein. The protective effect of GPPGPAG on Aβ1-42-induced dendritic atrophy was canceled by knockdown of 14-3-3ε. Taken together, these results suggest that GPPGPAG is orally available, transfers to the brain, and ameliorates memory dysfunction in AD brain, which is possibly mediated by 14-3-3ε-related dendritic restoration.


Cells ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1802
Author(s):  
Enrique Armijo ◽  
George Edwards ◽  
Andrea Flores ◽  
Jorge Vera ◽  
Mohammad Shahnawaz ◽  
...  

Alzheimer’s disease (AD) is the most common type of dementia in the elderly population. The disease is characterized by progressive memory loss, cerebral atrophy, extensive neuronal loss, synaptic alterations, brain inflammation, extracellular accumulation of amyloid-β (Aβ) plaques, and intracellular accumulation of hyper-phosphorylated tau (p-tau) protein. Many recent clinical trials have failed to show therapeutic benefit, likely because at the time in which patients exhibit clinical symptoms the brain is irreversibly damaged. In recent years, induced pluripotent stem cells (iPSCs) have been suggested as a promising cell therapy to recover brain functionality in neurodegenerative diseases such as AD. To evaluate the potential benefits of iPSCs on AD progression, we stereotaxically injected mouse iPSC-derived neural precursors (iPSC-NPCs) into the hippocampus of aged triple transgenic (3xTg-AD) mice harboring extensive pathological abnormalities typical of AD. Interestingly, iPSC-NPCs transplanted mice showed improved memory, synaptic plasticity, and reduced AD brain pathology, including a reduction of amyloid and tangles deposits. Our findings suggest that iPSC-NPCs might be a useful therapy that could produce benefit at the advanced clinical and pathological stages of AD.


Nature ◽  
2000 ◽  
Vol 408 (6815) ◽  
pp. 982-985 ◽  
Author(s):  
Dave Morgan ◽  
David M. Diamond ◽  
Paul E. Gottschall ◽  
Kenneth E. Ugen ◽  
Chad Dickey ◽  
...  

2016 ◽  
Vol 2016 ◽  
pp. 1-16 ◽  
Author(s):  
Anna Papazoglou ◽  
Julien Soos ◽  
Andreas Lundt ◽  
Carola Wormuth ◽  
Varun Raj Ginde ◽  
...  

Alzheimer’s disease (AD) is a multifactorial disorder leading to progressive memory loss and eventually death. In this study an APPswePS1dE9 AD mouse model has been analyzed using implantable video-EEG radiotelemetry to perform long-term EEG recordings from the primary motor cortex M1 and the hippocampal CA1 region in both genders. Besides motor activity, EEG recordings were analyzed for electroencephalographic seizure activity and frequency characteristics using a Fast Fourier Transformation (FFT) based approach. Automatic seizure detection revealed severe electroencephalographic seizure activity in both M1 and CA1 deflection in APPswePS1dE9 mice with gender-specific characteristics. Frequency analysis of both surface and deep EEG recordings elicited complex age, gender, and activity dependent alterations in the theta and gamma range. Females displayed an antithetic decrease in theta (θ) and increase in gamma (γ) power at 18-19 weeks of age whereas related changes in males occurred earlier at 14 weeks of age. In females, theta (θ) and gamma (γ) power alterations predominated in the inactive state suggesting a reduction in atropine-sensitive type II theta in APPswePS1dE9 animals. Gender-specific central dysrhythmia and network alterations in APPswePS1dE9 point to a functional role in behavioral and cognitive deficits and might serve as early biomarkers for AD in the future.


Sign in / Sign up

Export Citation Format

Share Document