Biology subjects

Musardo, S.

Publications and source records attributed to Musardo, S..

6 recordsLinked to original sources

bioRxiv2025

Oxytocin release modulates acute neuroinflammation and improves brain development after pediatric traumatic brain injury

Pediatric traumatic brain injury (TBI) is a leading cause of death and disability early in life in infants, and its neurodevelopmental consequences cannot currently be effectively treated. Since TBI is associated with neuroinflammation, modulation of the post-injury neuroinflammatory response is a promising strategy. Oxytocin is thought to have anti-inflammatory properties and appears to play a role in clinical interventions that improve brain development in neonates. However, the underlying mechanisms remain unclear, as does its applicability to acute brain injury. Here we investigate the effects of chemogenetic modulation of endogenous oxytocin on acute neuroinflammation and on long-term brain development after TBI in postnatal day 7 (P7) male mice. We show that oxytocin release attenuates the acute neuroinflammatory response to TBI 24 hours after injury, by reducing the expression of immune- and inflammation-related genes in astrocytes and promoting gene pathways for brain repair and development in microglia. In the long term, oxytocin exposure ameliorates subcortical and cortical white matter damage after TBI, prevents hyperactivity and loss of social behavior, and restores TBI-induced alterations in resting-state functional connectivity of the isocortex. These findings enhance our understanding of the modulation of neuroinflammation and its long-term effects and support intervention related to endogenous oxytocin release as a promising neuroprotective strategy in pediatric TBI.

neuroscience↗

bioRxiv2021

Inhibition of TRPV4 rescues circuit and social deficits unmasked by acute inflammatory response in a Shank3 mouse model of Autism

Autism spectrum disorder is a neurodevelopmental disease characterized by social deficits and repetitive behaviors. The high heterogeneity of the disease may be explained by gene and environmental interactions and potential risk factors include immune dysfunctions and immune-mediated co-morbidities. Mutations in the SHANK3 gene have been recognized as a genetic risk factor for ASD. While heterozygous SHANK3 mutations are usually the types of mutations associated with idiopathic autism in patients, heterozygous deletion of Shank3 gene in mice does not commonly induce ASD-related behavioural deficit. Here, we used in-vivo and ex-vivo approaches to demonstrate that region-specific neonatal downregulation of Shank3 in the NAc promotes D1R-MSN hyperexcitability and upregulates Trpv4 to impair social behaviour. Interestingly, genetically vulnerable Shank3+/- mice, when challenged with Lipopolysaccharide to induce inflammatory response, showed similar circuit and behavioural alterations that were rescued by acute Trpv4 inhibition. Altogether our data demonstrate shared molecular and circuit mechanisms between ASD-relevant genetic alterations and environmental insults, which ultimately lead to sociability dysfunctions.

neuroscience↗

bioRxiv2021

Oxytocin neurons mediates the effect of social isolation via the VTA circuits

Social interaction during adolescence strongly influences brain function and behaviour, and the recent pandemic has emphasized the devastating effect of social distancing on mental health. While accumulating evidences have shown the importance of the reward system in encoding specific aspects of social interaction, the consequences of social isolation on the reward system and the development of social skills later in adulthood are still largely unknown. Here, we found that one week of social isolation during adolescence in mice increased social interaction at the expense of social habituation and social novelty preference. Behavioural changes were accompanied by the acute hyperexcitability of dopamine (DA) neurons in the ventral segmental area (VTA) and long-lasting expression of GluA2-lacking AMPARs at excitatory inputs onto DA neurons that project to the prefrontal cortex (PFC). Social isolation-dependent behavioural deficits and changes in neural activity and synaptic plasticity were reversed by chemogenetic inhibition of oxytocin neurons in the paraventricular nucleus (PVN) of the hypothalamus. These results demonstrate that social isolation has acute and long-lasting effects on social interaction and suggest that these effects are mediated by homeostatic adaptations within the reward circuit.

neuroscience↗

bioRxiv2021

Optogenetic stimulation of BLA terminals in the BNST elicits long term synaptic plasticity and restores synaptic alterations induced by adolescent Shank3 downregulation

Anxiety disorders are the most prevalent co-morbidity factor associated with the core domains of Autism Spectrum Disorders (ASD). Investigations on potential common neuronal mechanisms that may explain the co-occurrence of ASD and anxiety disorders are still poorly unexplored. One of the key questions which remained unsolved is the role of Shank3 protein in anxiety behaviors. Here we used shRNA strategy to model Shank3 insufficiency in the bed nucleus of the stria terminalis (BNST). We found that Shank3 downregulation in the BNST induced anxiogenic effects. Associated with these behavioural defects, we showed alteration of glutamatergic synaptic functions in the BNST induced by Shank3 insufficiency during adolescence. In addition, we pointed that adolescence represents a crucial time window to interfere with BNST maturation, a key hub for anxiety control. Together, these results unravelled the crucial role of Shank3 expression in the BNST during adolescence. Our study provided a new insight in the neuronal mechanisms underlying anxiety disorders. We proposed to screen a novel molecular target essential for BNST integrity during adolescence. This result may further help for the diagnosis and the development of therapeutic strategy for anxiety disorders and anxiety disorders implicated in some forms of ASD.

neuroscience↗

bioRxiv2019

Superior Colliculus to VTA pathway controls orienting behavior during conspecific interaction.

Social behaviours characterize cooperative, mutualistic aggressive or parental interactions that occurs among conspecifics. Although several neuronal substrates of social behaviour have been identified, whether defined circuits are dedicated to specific aspect of conspecific interaction is still an open question. Ventral Tegmental Area (VTA) contributes to the rewarding properties of conspecific interaction. However, how information related to conspecifics are conveyed to the VTA is still largely unknown. In this study, we identified a population of Superior Colliculus (SC) neurons projecting to the VTA which increase their activity before conspecific interaction and control orienting response towards unfamiliar conspecifics. Finally, we show that SC inputs target a subpopulation of Dopamine (DA) neurons within the VTA that in turn project to dorsolateral striatum (DLS). Our work supports the hypothesis that specialized sub-circuits are dedicated to process different aspect of social interaction.

neuroscience↗

bioRxiv2018

Neuronal signature of social novelty exploration in the VTA: implication for Autism Spectrum Disorder

Novel stimuli attract our attention, promote exploratory behavior, and facilitate learning. Atypical habituation and aberrant novelty exploration have been related with the severity of Autism Spectrum Disorders (ASD) but the underlying neuronal circuits are unknown. Here, we report that dopamine (DA) neurons of the ventral tegmental area (VTA) promote the behavioral responses to novel social stimuli, support preference for social novelty, and mediate the reinforcing properties of novel social interaction. Social novelty exploration is associated with the insertion of calcium-permeable GluA2-lacking AMPA-type glutamate receptors at excitatory synapses on VTA DA neurons. These novelty-dependent synaptic adaptations only persist upon repeated exposure to social stimuli and sustain social interaction. Global or DA neuron-specific inactivation of the ASD risk gene Neuroligin3 alters both social novelty exploration and the reinforcing properties of social stimuli. These behavioral deficits are accompanied by an aberrant expression of non-canonical GluA2-lacking AMPA-receptors at excitatory synapses on VTA DA neurons and an occlusion of novelty-induced synaptic plasticity. Altogether, these findings causally link impaired novelty exploration in an ASD mouse model to VTA DA circuit dysfunction.

neuroscience↗