Sodium Channel Inhibitors Reduce DMPK mRNA and Protein. Issue 4 (22nd May 2015)

• Record Type: Journal Article
• Authors: Witherspoon, Luke; O'Reilly, Sean; Hadwen, Jeremiah; Tasnim, Nafisa; MacKenzie, Alex; Farooq, Faraz
• Is Part Of: Clinical and translational science. Volume 8:Issue 4(2015)
• Page Start: 298
• Page End: 304
• Publication Date: 2015-05-22
• Subjects: Medicine, Experimental -- Periodicals; Medical innovations -- Periodicals; 616.027
• DOI: 10.1111/cts.12275
• Languages: English
• ISSNs: 1752-8054

Abstract

<abstract abstract-type="main"> <title>Abstract</title> <p>Myotonic dystrophy type 1 (DM1) is caused by an expanded trinucleotide (CTG)n tract in the 3′ untranslated region (UTR) of the dystrophia myotonica protein kinase (<italic>DMPK</italic>) gene. This results in the aggregation of an expanded mRNA forming toxic intranuclear foci which sequester splicing factors. We believe down‐regulation of DMPK mRNA represents a potential, and as yet unexplored, DM1 therapeutic avenue. Consequently, a computational screen for agents which down‐regulate DMPK mRNA was undertaken, unexpectedly identifying the sodium channel blockers mexiletine, prilocaine, procainamide, and sparteine as effective suppressors of DMPK mRNA. Analysis of DMPK mRNA in C2C12 myoblasts following treatment with these agents revealed a reduction in the mRNA levels. <italic>In vivo</italic> analysis of CD1 mice also showed DMPK mRNA and protein down‐regulation. The role of DMPK mRNA suppression in the documented efficacy of this class of compounds in DM1 is worthy of further investigation.</p> </abstract>