Introducing Alzheimer's & Dementia: Diagnosis, Assessment & Disease Monitoring, an open access journal of the Alzheimer's Association

The Oligomeric Form of Amyloid Beta Triggers Astrocyte Activation, Independent of Neurons

The most common aging-related neurodegenerative disorder is Alzheimer's disease (AD), of which the main symptom is memory disturbance. Though the mechanism of AD pathogenesis is not fully defined, abnormal aggregation of amyloid beta (Aβ) plaques and tau have been considered as key factors and main histological hallmarks of the disease. Astrocyte is responsible for the control of cells and the environment around brain and spinal cord cells. Astrocytes have been implicated with AD. However, the exact function of astrocytes in AD has not been established. In this study, we investigated the regulation of astrocytes in the AD model using primary cultures. We have demonstrated that oligomerized Aβ is toxic to neurons and can induce cell death in primary cultures. In the primary cultures containing neurons and astrocytes, amyloid beta uptake was observed in both neurons and astrocytes. To verify if the uptake of amyloid beta in astrocytes is dependent on neurons, we separated and cultured primary astrocytes with no neurons. Amyloid uptake was still observed in this pure astrocyte culture, suggesting that the uptake of amyloid beta is a neuron-independent function of astrocytes. Astrocyte activation was observed in both pure and mixed cultures. Taken together, our data suggest that astrocyte is activated by oligomerized Aβ and uptakes it, which is independent of neurons.

How technology is reshaping cognitive assessment: Lessons from the Framingham Heart Study

OBJECTIVE

This article elucidates how the Boston process approach (BPA) can amplify the role of neuropsychology in the study of preclinical and clinical dementia, particularly Alzheimer's disease (AD), and how advancements in technology expand BPA capacity objectively and exponentially.

METHOD

The BPA is based on a conceptualization of cognition as being comprised of multiple processes, the nature of which could not possibly be captured by a single score on a test or battery of tests. Identification of these processes is only possible with careful observation of an individual during the entire testing process to determine how, when, and why a person fails, which helps to reveal the integrity of the cognitive processes underlying the behavior.

RESULTS

BPA use within the Framingham Heart Study is described, including how digital technology has been incorporated to enhance the sensitivity of BPA to detect insidious onset changes even earlier than had been previously possible. The digital technology movement will dramatically alter the means by which cognitive function is assessed going forward.

CONCLUSIONS

Technological advances will catalyze groundbreaking discoveries for effective treatments of neurodegenerative cognitive disorders, such as AD, and inform novel strategies for dementia prevention and sustained lifelong cognitive health. (PsycINFO Database Record