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Lefevre, A.

Publications and source records attributed to Lefevre, A..

2 recordsLinked to original sources

Oxytocin Acts on Astrocytes in the Central Amygdala to Promote a Positive Emotional State

Oxytocin orchestrates social and emotional behaviors through modulation of neural circuits in brain structures such as the central amygdala (CeA). The long-standing dogma is that oxytocin signaling in the central nervous system occurs exclusively via direct actions on neurons. However, several findings over the last decades showed that astrocytes actively participate in the modulation of neuronal circuits. Here, we investigate the degree of astrocytes involvement in oxytocin functions. Using astrocyte specific gain and loss of function approaches, we demonstrate that CeA astrocytes not only directly respond to oxytocin, but are actually necessary for its effects on neuronal circuits and ultimately behavior. Our work identifies astrocytes as a crucial cellular substrate underlying the promotion of a positive emotional state by oxytocin. These results further corroborate that astrocytes are key regulators of neuronal circuits activity by responding to specific neuropeptidergic inputs, and opens up new perspectives to understand how neuromodulators gate brain functions.

neuroscience

Efficacy of chronic ultrasound neurostimulation on behaviors and distributed brain metabolism in depressive-like mice

Major depression is one of the main factors contributing to the Global Burden of Disease. Current treatment strategies (e.g., antidepressants and neurostimulation techniques) of major depression show some limitations including inaccuracy and invasiveness. Ultrasound neurostimulation (USNS) has been recently introduced as a physical non-invasive method for brain tissue stimulation and has gained increasing interest. In this study, we sought to evaluate the efficacy of transcranial USNS in an unpredictable chronic mild stress (UCMS) mouse model. The results show that transcranial USNS of the infralimbic cortex reduced anxiety-related behaviors as well as some, but not all, depression-related parameters. [18F]-FDG microPET imaging and brain metabolomic analyses showed that USNS triggered the activation of targeted brain region in addition to brain areas at a distance from the targeted zone, alleviating anxiety and depression-related behaviors induced by the UCMS regimen. Transcranial ultrasound neurostimulation show therapeutic potential in some aspects of major depression.

neuroscience