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Jeanneteau, F.

Publications and source records attributed to Jeanneteau, F..

3 recordsLinked to original sources

Acquiring social safety engages oxytocin neurons in the supraoptic nucleus - role of Magel2 deficiency

IntroductionExposure to social trauma may alter engagement with both fear-related and unrelated social stimuli long after. Intriguingly, how simultaneous discrimination of social fear and safety is affected in neurodevelopmental conditions like autism remains underexplored. The role of the neuropeptide oxytocin is established in social behaviors, and yet unexplored during such a challenge post-social trauma. MethodsUsing Magel2 knockout mice, an animal model of Prader Willi Syndrome (PWS) and autism spectrum disorders, we tested memory of social fear and safety after a modified social fear conditioning task. Additionally, we tracked the activity of oxytocin neurons in the supraoptic (SON) and paraventricular (PVN) nuclei of the hypothalamus by fibre photometry, as animals were simultaneously presented with a choice between a fear and safe social cue during recall. ResultsMale Magel2 KO mice trained to fear females with electrical footshocks avoided both unfamiliar females and males during recalls, lasting even a week post-conditioning. On the contrary, trained Magel2 WT avoided only females during recalls, lasting days rather than a week post-conditioning. Inability to overcome social fear and avoidance of social safety in Magel2 KO mice were associated with reduced engagement of oxytocin neurons in the SON, but not the PVN. ConclusionIn a preclinical model of PWS, we demonstrated region-specific deficit in oxytocin activity associated with behavioral generalization of social fear to social safety. Insights from this study add to our understanding of oxytocin action in the brain at the intersection of social trauma, PWS and related autism spectrum disorders.

neuroscience↗

The impact of C-Tactile Low threshold mechanoreceptors on affective touch and social interactions in mice.

Affective touch is necessary for proper neurodevelopment and sociability. However, it is still unclear how the neurons innervating the skin detect affective and social behaviours. To clarify this matter, we targeted a specific population of somatosensory neurons in mice, named C-low threshold mechanoreceptors (C-LTMRs), that appears particularly well suited physiologically and anatomically to perceive affective and social touch but whose contribution to these processes has not yet been resolved. Our observations revealed that C-LTMRs functional deficiency from birth induced social isolation and reduced tactile interactions in adults. Conversely, transient increase in C-LTMRs excitability in adults using chemogenetics was rewarding, temporally promoted touch seeking behaviours and thus had pro-social effects on group dynamics. This work provides the first empirical evidence that specific peripheral inputs alone can drive complex social behaviour, demonstrating the existence of a specialised neuronal circuit originating from the skin wired to promote interaction with other individuals.

neuroscience↗

Control of Social Withdrawal of Mice Deficient for the Autism Gene Magel2 by Restoration of Vasopressin-Oxytocin Dialogue in Septum

Intellectual and social disabilities are common comorbidities in adolescents and adults with Magel2 gene deficiency characterizing the Prader-Willi and Schaaf-Yang neurodevelopmental syndromes. The cellular and molecular mechanisms underlying the risk for autism in these syndromes are unexplored. Here we used Magel2 knockout mice combined with optogenetic/pharmacological tools to characterize disease modifications in the social brain network. We find that the degree of social novelty moderates a dialogue between vasopressin and oxytocin in the lateral septum, a region organizing sequential content of sensory experiences. Social withdrawal of mice lacking Magel2 is alleviated by restoration of dialogue-lead by vasopressin. This preclinical study identifies the collective actions of vasopressin and oxytocin in the lateral septum as a key factor in the pathophysiology.

neuroscience↗