astrocyte

Astroglial Disinhibition of Cortical Circuits Disrupts Cognition via Kynurenic Acid in Mice

Astrocytes play critical roles in neural circuit function, but how they contribute to cognitive impairment remains poorly understood. Here, we identify astrocyte-derived kynurenic acid (KYNA), a neuroactive metabolite known to modulate multiple neurotransmitter receptor systems, including the N-methyl-D-aspartate receptor (NMDA), as a mediator of cognitive dysfunction in the context of aberrant astrocyte activity. Using chemogenetic stimulation, pharmacological rescue, and astrocyte-specific knockdown of kynurenine aminotransferase II (KAT II) in mice, we show that elevated KYNA suppresses parvalbumin-positive interneuron activity in the prefrontal cortex, leading to disinhibition of pyramidal neurons and impairments in cognitive functions linked to cortical activity, including episodic-like and working memory as well as sensorimotor gating. These findings define an astrocyte-KYNA-interneuron axis that controls cortical excitability and cognition, linking glial metabolism to circuit imbalance and cognitive dysfunction with potential relevance to psychiatric and neurological disorders.

Researchers

Viktor Beilmann
Viktor Beilmann
Johanna Furrer
Dr. Johanna Furrer
Sina M. Schalbetter
Ron Shaer
Edoardo Tiziani
Kim David Ferrari
Felisa Herrero
Celine Heeb
Alexandra von Faber-Castell
Alexandra von Faber-Castell
Jacqueline Condrau
Dr. Jacqueline Condrau
Ulrike Weber-Stadlbauer
Matthias Wyss
PD Dr. Dr. Matthias T Wyss
Aiman
Prof. Dr. Aiman Saab
Sarah Beggiato
Urs Meyer
Prof. Dr. Bruno Weber
Prof. Dr. Bruno Weber
Dr. Tina Notter
Dr. Tina Notter