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Louette, E.

Publications and source records attributed to Louette, E..

2 recordsLinked to original sources

Chlorzoxazone, A BKCa Channel Agonist, Rescues The Pathological Phenotypes Of Williams-Beuren Syndrome In A Preclinical Model

Williams-Beuren syndrome (WBS) is a rare developmental disorder caused by the deletion of a 1.5 Mb region in chromosome 7 (7q11.23). WBS has been recently modelled by a mutant mouse line having a complete deletion (CD) of the equivalent locus on mouse chromosome 5, thus resembling the genetic defect found in WBS patients. CD mice have been shown to have physical and neurobehavioral abnormalities that recapitulate most of the symptoms associated with human WBS, including cardiovascular, motor, social, emotional and sensory alterations. This model has been largely used to investigate the etiopathological mechanisms of WBS; nonetheless, pharmacological therapies for this syndrome have not been identified yet. Here we propose a novel treatment for WBS, chlorzoxazone (CHLOR), i.e., a molecule targeting calcium-activated large conductance potassium (BKCa) channels, since a reduction in the expression of these channels has been recently described in neurons from WBS patients, as well as in other rare developmental pathologies. Our results demonstrate both the acute and chronic effects of CHLOR on some major pathological phenotypes of CD mice, including several behavioural alterations and cardiac hypertrophy. We conclude that BKCa channels are a therapeutic target of high potential for clinical applications and are likely to play a key role in the etiopathology of WBS.

neuroscience

Therapeutic effects of Chlorzoxazone, a BKCa channel agonist, in a mouse model of Fragile X syndrome

Fragile X syndrome (FXS) is an X-linked developmental disorder characterized by several behavioral abnormalities, including hyperactivity, sensory hyper-responsiveness and cognitive deficits, as well as autistic symptoms, e.g., reduced social interaction. These behavioural alterations are recapitulated by the major animal model of FXS, i.e., the Fmr1-KO mouse, which has been extensively employed to identify therapeutic targets for FXS, though effective pharmacological treatments are still lacking. Here we focused on the therapeutic role of large-conductance Calcium-dependent potassium (BKCa) channels, playing a crucial role in neuronal excitability and neurotransmitter release. Reduced expression/functionality of these channels has been described in FXS patients and mice, so that molecules activating these channels have been proposed as promising treatments for this syndrome. Here we performed an extensive characterization of the therapeutic impact of a novel BKCa agonist on FXS-like symptoms in the Fmr1-KO mouse model, employing a drug repurposing setting. We evaluated the acute and chronic effects of chlorzoxazone, i.e., a classical drug used for non-developmental muscular pathologies, on the locomotor, social, cognitive and sensory-motor alterations of Fmr1-KO mice and compared them with other pharmacological treatments recently proposed for FXS that instead do not target BKCa channels. Our results clearly demonstrate for the first time the marked efficacy of chlorzoxazone in treating all the behavioral abnormalities of FXS mice, thus encouraging the preferential use of this molecule over others for clinical applications in the field of FXS, and potentially of other neurodevelopmental disorders.

neuroscience