Astrocyte Gliotransmission in the Regulation of Systemic Metabolism

Abstract

Normal brain function highly relies on the appropriate functioning of astrocytes. These glial cells are strategically situated between blood vessels and neurons, provide significant substrate support to neuronal demand, and are sensitive to neuronal activity and energy-related molecules. Astrocytes respond to many metabolic conditions and regulate a wide array of physiological processes, including cerebral vascular remodeling, glucose sensing, feeding, and circadian rhythms for the control of systemic metabolism and behavior-related responses. This regulation ultimately elicits counterregulatory mechanisms in order to couple whole-body energy availability with brain function. Therefore, understanding the role of astrocyte crosstalk with neighboring cells via the release of molecules, e.g., gliotransmitters, into the parenchyma in response to metabolic and neuronal cues is of fundamental relevance to elucidate the distinct roles of these glial cells in the neuroendocrine control of metabolism. Here, we review the mechanisms underlying astrocyte-released gliotransmitters that have been reported to be crucial for maintaining homeostatic regulation of systemic metabolism.

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“…ADCYAP1 gene encodes pituitary adenylate cyclase-activating polypeptide (Bakalar et al, 2021) which contributes to energy homeostasis (Rudecki and Gray, 2016;Bozadjieva-Kramer et al, 2021;Gastelum et al, 2021), and astroglial functions are modulated by PACAP (Masmoudi-Kouki et al, 2007;Hansson et al, 2009;Nakamachi et al, 2011;Kong et al, 2016;Seo and Lee, 2016;Kambe et al, 2021), and respond to many metabolic demands regulating a wide array of physiological processes (Murat and García-Cáceres, 2021) including hippocampaldependent behavioral functions (Johnson et al, 2020).…”

Obesity-Related Neuroinflammation: Magnetic Resonance and Microscopy Imaging of the Brain

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Astrocytes as a Therapeutic Target in Alzheimer’s Disease–Comprehensive Review and Recent Developments

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