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Casarotto, G.

Publications and source records attributed to Casarotto, G..

2 recordsLinked to original sources

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↗

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↗