Investigating changes in β-adrenergic gene expression (ADRB1 and ADRB2) in Takotsubo (stress) cardiomyopathy syndrome; a pilot study.

Background: Takotsubo Cardiomyopathy (TC) is a rare disorder that is mostly caused by stress and is often misdiagnosed. We aimed to analyze Takotsubo Syndrome at the molecular level by using the Oxford Nanopore Minion Device and its protocol.

Methods And Results: Ten patients who were previously diagnosed with Takotsubo Syndrome (increased after decrease in ejection fraction and without critical stenosis in coronary arteries) and 10 healthy individuals in the control group were included in our project. The mean age was 53 ± 12.2 for the patient group and 52.4 ± 9.9 for the control group, and the left ventricular ejection fraction was 50.3 ± 11.5 for the patient group and 64.2 ± 2.8 for the control group (p < 0.05). Peripheral blood of patients and healthy individuals was taken and their DNA was obtained. By making long reads throughout the genome, the most studied regions responsible for β-adrenergic signaling pathways; The gene expression level of cardiac β-1 ADRB1 (rs1801253-ENST00000369295.4), G > C, (Gly389Arg) and cardiac β-2 ADRB2 (rs1800888-ENSG00000169252), C > T, (Thr165Ile) adrenoceptors was investigated. As a result; no structural variation was detected leading to Takotsubo Cardiomyopathy. The results obtained from the bioinformatics analysis were also checked from the VarSome Tools and similar results were found.

Conclusions: Many publications in TC susceptibility have that may lead to adrenergic pathway dysregulation, most studied adrenergic receptor genes in the similar literatures too. We searched for genetic variants in b1AR and b2AR genes in our study and however we could not find any variants in this study, we think larger numbers of cohort studies are needed.