• About
    • Login
    View Item 
    •   Institutional Repository Home
    • Electronic Theses and Dissertations
    • Electronic Theses and Dissertations
    • View Item
    •   Institutional Repository Home
    • Electronic Theses and Dissertations
    • Electronic Theses and Dissertations
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Browse

    All of Institutional RepositoryCommunities & CollectionsBy Issue DateAuthorsTitlesSubjectsThis CollectionBy Issue DateAuthorsTitlesSubjects

    My Account

    LoginRegister

    PHARMACOLOGICAL AND GENETIC APPROACHES PROBING THE ROLE OF THE SLACK POTASSIUM CHANNEL IN CHILDHOOD EPILEPSIES

    Spitznagel, Brittany
    0000-0003-4172-4147
    : http://hdl.handle.net/1803/16402
    : 2020-11-16

    Abstract

    Malignant migrating partial seizures of infancy is a rare, devastating form of epilepsy most commonly associated with gain-of-function mutations in the potassium channel, Slack. Not only is this condition almost completely pharmacoresistant, there are not even selective drug-like tools available to evaluate whether inhibition of these over-activated, mutant Slack channels may represent a viable path forward toward new anti-epileptic therapies. Therefore, we used a high-throughput thallium flux assay to screen a drug-like, 100,000-compound library in search of inhibitors of both wild-type and a disease-associated mutant Slack channel. Using this approach, we discovered VU0606170, a selective Slack channel inhibitor with low µM potency. Critically, VU0606170 also proved effective at significantly decreasing the firing rate in over-excited, spontaneously firing cortical neuron cultures. Additionally, we have generated a mouse model of this condition by replacing the wild-type gene with one encoding KCNT1 A913T, a cytoplasmic C-terminal mutation homologous to the human A934T variant that results in MMPSI. We compared behavior patterns and seizure activity in these mice with those of wild-type mice. Anxiety-related behaviors were found to be increased in KCNT1+/A913T and KCNT1A913T/A913T animals in a gene dose-dependent manner. Similarly, increased response to startle stimuli and decreased sensorimotor gating were altered in a gene dose-dependent manner. Video-EEG monitoring of KCNT1+/A913T and KCNT1A913T/A913T animals revealed persistent interictal spikes and spontaneous seizures. Taken together, our data provide two critical tools for advancing our understanding of the role of the Slack channel in normal physiology and disease, as well as its potential as a target for therapeutic intervention. We have generated a novel animal model of MMPSI, recapitulating several phenotypes seen in this patient population, including an increase in anxiety-like behaviors, deficits in sensorimotor gating and the presence of spontaneous seizures. Furthermore, the identification and extensive characterization of VU0606170 provides compelling evidence that selective inhibition of Slack channel activity can be achieved with small molecules and that inhibition of Slack channel activity in neurons produces efficacy consistent with an anti-epileptic effect. All in all, these studies provide a promising foundation for the drug discovery efforts for these important channels and provide a framework for evaluating Slack inhibitors in vivo.
    Show full item record

    Files in this item

    Icon
    Name:
    SPITZNAGEL-DISSERTATION-2020.pdf
    Size:
    3.403Mb
    Format:
    PDF
    View/Open

    This item appears in the following collection(s):

    • Electronic Theses and Dissertations

    Connect with Vanderbilt Libraries

    Your Vanderbilt

    • Alumni
    • Current Students
    • Faculty & Staff
    • International Students
    • Media
    • Parents & Family
    • Prospective Students
    • Researchers
    • Sports Fans
    • Visitors & Neighbors

    Support the Jean and Alexander Heard Libraries

    Support the Library...Give Now

    Gifts to the Libraries support the learning and research needs of the entire Vanderbilt community. Learn more about giving to the Libraries.

    Become a Friend of the Libraries

    Quick Links

    • Hours
    • About
    • Employment
    • Staff Directory
    • Accessibility Services
    • Contact
    • Vanderbilt Home
    • Privacy Policy