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bioRxiv · 10.1101/2022.07.21.500921

Mechanistic multiscale modelling of energy metabolism in human astrocytes indicates morphological effects in Alzheimer's Disease

Abstract

Astrocytes with their specialized morphology are essential for brain homeostasis as metabolic mediators between blood vessels and neurons. In neurodegenerative diseases such as Alzheimers disease (AD), astrocytes adopt reactive profiles with molecular and morphological changes that could lead to the impairment of their metabolic support and impact disease progres-sion. However, the underlying mechanisms how metabolic function of human astrocytes is impaired by their morphological changes in AD is still elusive. To address this challenge, we developed and applied a metabolic multiscale modelling approach integrating the dynamics of metabolic energy pathways and physiological astrocyte morphologies acquired in human AD and age-matched control brain samples. The results demonstrate that the complex cell shape and intracellular organization of energetic pathways determine the metabolic profile and support capacity of astrocytes in health and AD conditions. Thus, our mechanistic approach indicates the importance of spatial orchestration in metabolism and allows for the identification of protective mechanisms against disease-associated metabolic impairments.

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Farina, S., Voorsluijs, V., Fixemer, S., Bouvier, D., Claus, S., Bordas, S. P. A., Skupin, A.. 2022-07-22. Mechanistic multiscale modelling of energy metabolism in human astrocytes indicates morphological effects in Alzheimer's Disease. https://doi.org/10.1101/2022.07.21.500921

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