Frontiers in Cell and Developmental Biology (Nov 2019)

Studying Brugada Syndrome With an SCN1B Variants in Human-Induced Pluripotent Stem Cell-Derived Cardiomyocytes

  • Ibrahim El-Battrawy,
  • Ibrahim El-Battrawy,
  • Jonas Müller,
  • Jonas Müller,
  • Zhihan Zhao,
  • Zhihan Zhao,
  • Lukas Cyganek,
  • Lukas Cyganek,
  • Rujia Zhong,
  • Feng Zhang,
  • Mandy Kleinsorge,
  • Mandy Kleinsorge,
  • Huan Lan,
  • Huan Lan,
  • Huan Lan,
  • Xin Li,
  • Qiang Xu,
  • Mengying Huang,
  • Zhenxing Liao,
  • Alexander Moscu-Gregor,
  • Sebastian Albers,
  • Sebastian Albers,
  • Hendrik Dinkel,
  • Siegfried Lang,
  • Siegfried Lang,
  • Sebastian Diecke,
  • Wolfram-Hubertus Zimmermann,
  • Wolfram-Hubertus Zimmermann,
  • Jochen Utikal,
  • Jochen Utikal,
  • Thomas Wieland,
  • Thomas Wieland,
  • Martin Borggrefe,
  • Martin Borggrefe,
  • Xiaobo Zhou,
  • Xiaobo Zhou,
  • Xiaobo Zhou,
  • Ibrahim Akin,
  • Ibrahim Akin

DOI
https://doi.org/10.3389/fcell.2019.00261
Journal volume & issue
Vol. 7

Abstract

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BackgroundAmong rare channelopathies BrS patients are at high risk of sudden cardiac death (SCD). SCN5A mutations are found in a quarter of patients. Other rare gene mutations including SCN1B have been implicated to BrS. Studying the human cellular phenotype of BrS associated with rare gene mutation remains lacking.ObjectivesWe sought to study the cellular phenotype of BrS with the SCN1B gene variants using human-induced pluripotent stem cell (hiPSCs)–derived cardiomyocytes (hiPSC-CMs).Methods and ResultsA BrS patient suffering from recurrent syncope harboring a two variants (c.629T > C and c.637C > A) in SCN1B, which encodes the function-modifying sodium channel beta1 subunit, and three independent healthy subjects were recruited and their skin biopsies were used to generate hiPSCs, which were differentiated into cardiomyocytes (hiPSC-CMs) for studying the cellular electrophysiology. A significantly reduced peak and late sodium channel current (INa) and a shift of activation curve to more positive potential as well as a shift of inactivation curve to more negative potential were detected in hiPSC-CMs of the BrS patient, indicating that the SCN1B variants impact the function of sodium channels in cardiomyocytes. The reduced INa led to a reduction of amplitude (APA) and upstroke velocity (Vmax) of action potentials. Ajmaline, a sodium channel blocker, showed a stronger effect on APA and Vmax in BrS cells as compared to cells from healthy donors. Furthermore, carbachol was able to increase arrhythmia events and the beating frequency in BrS.ConclusionOur hiPSC-CMs from a BrS-patient with two variants in SCN1B recapitulated some key phenotypic features of BrS and can provide a platform for studies on BrS with SCN1B variants.

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