Effect of isoprenaline and arrhythmogenic conditions on the spontaneous electrical activity of hiPSC-CM with Y4734C-RYR2 variant

KRÁL, Martin, Olga ŠVECOVÁ, Štefan ZELENÁK, Jiří PACHERNÍK, Tomáš BÁRTA, Jana ZÍDKOVÁ, Iva SYNKOVÁ, Samuel LIETAVA, Tomáš NOVOTNÝ and Markéta BÉBAROVÁ. Effect of isoprenaline and arrhythmogenic conditions on the spontaneous electrical activity of hiPSC-CM with Y4734C-RYR2 variant. In 48th Meeting of the European Working Group on Cardiac Cellular Electrophysiology. 2024.

Basic information

• Original name: Effect of isoprenaline and arrhythmogenic conditions on the spontaneous electrical activity of hiPSC-CM with Y4734C-RYR2 variant
• Authors: KRÁL, Martin, Olga ŠVECOVÁ, Štefan ZELENÁK, Jiří PACHERNÍK, Tomáš BÁRTA, Jana ZÍDKOVÁ, Iva SYNKOVÁ, Samuel LIETAVA, Tomáš NOVOTNÝ and Markéta BÉBAROVÁ.
• Edition: 48th Meeting of the European Working Group on Cardiac Cellular Electrophysiology, 2024.

Other information

• Original language: English
• Type of outcome: Conference abstract
• Country of publisher: Austria
• Confidentiality degree: is not subject to a state or trade secret
• Organization unit: Faculty of Medicine
• Keywords in English: RYR2, Y4734C, multielectrode array, electrical activity, isoprenaline
• Tags: International impact, Reviewed

Abstract

Background: In a proband with idiopathic ventricular fibrillation (IF) and in his sister suffering from catecholaminergic polymorphic ventricular tachycardia (CPVT), p.Y4734C-RYR2 variant was found. Here we bring data showing the spontaneous electrical activity of cardiomyocytes derived from human-induced pluripotent stem cells (hiPSC-CM) of the proband (IF), his sister (CPVT), and his healthy nephew as control (WT), and its changes under arrhythmogenic conditions. Methods: The recordings by the multielectrode array technique were performed in control, i.e. in Tyrode solution with 5 mM K+ (5K++37°C), in 0.5 µM isoprenaline (ISO), and under cumulatively added hypokalemia (3K+), β-adrenergic stimulation (ISO), and hyperthermia (40°C). Considering non-normal data distribution, the cycle length (CL) and its short-term variability (STVCL) are shown as the median from n samples and non-parametric tests were used. Results: In 5K+, CPVT hiPSC-CM had a significantly longer CL (1.47 s, n=19; P˂0.05) than IF (1.05 s, n=32) and WT (0.77 s, n=7). ISO significantly shortened CL in all groups (by 38.3, 22.7, and 17.7 % in CPVT, IF, and WT, respectively, n=19, 32, and 7; P ˂ 0.05) and CPVT showed a significantly larger reaction than IF (P˂0.05). The arrhythmogenic factors caused a significant increment in STVCL in IF (41.91 in 3K+, 22.65 in 3K++ISO, and 65.38 ms in 3K++ISO+40°C, vs. 10.23 ms in control; n=24; P˂0.05) whereas it was significantly increased only in 3K+ in CPVT (21.14, 15.99, and 10.44 ms, respectively, vs. 13.13 in control; n=20; P˂0.05). IF and CPVT significantly differed in STVCL in 3K++ISO+40°C. Conclusions: CPVT hiPSC-CM showed a lower frequency of spontaneous activity and its higher reactivity to ISO. An increment in beat-to-beat variability of CL was observed during arrhythmogenic conditions in IF hiPSC-CM.

Links

• MUNI/A/1547/2023, interní kód MU: Name: Analýza (dys)funkce: od molekul k živému organismu

Investor: Masaryk University, Analysis of (dys)function: from molecules to the living organism

• NU22-02-00348, research and development project: Name: Funkční hodnocení genetických variant u případů klinicky „skutečné“ idiopatické fibrilace komor: in vitro a in silico modelování s cílem odhalit arytmogenní mechanismus

Investor: Ministry of Health of the CR, Subprogram 1 - standard