Gut Microbiota Regulate Astrocytic Functions in the Brain: Possible Therapeutic Consequences

Astrocytes are essential for maintaining the homeostasis of the central nervous system (CNS). Astrocytic dysfunction has been implicated in the progression of several neurodegenerative and psychiatric diseases; however, a multitude of factors and signals influencing astrocytic activity have not been entirely elucidated. Astrocytes respond to local signals from the brain, but are also indirectly modulated by gut microbiota. Previous studies revealed that most of the CNS diseases triggered by astrocytic dysfunction are closely associated with the dysbiosis of gut microbiome. Emerging data from preclinical and clinical studies suggest that the maturation and functioning of astrocytes rely on gut microbiota, which plays a pivotal role in the decrease of astrocytic activation and may alleviate symptoms of brain diseases. Herein, we discuss the most recent advances concerning the complex connections between astrocytes and gut microbiota, which are involved in the immune, neurotransmission and neuroendocrine pathways. Deciphering these pathways will facilitate a better understanding of how perturbed gut microbiota contributes to the dysfunction of astrocytes and open therapeutic opportunities for the treatment of brain diseases.