Ontology highlight
ABSTRACT: Background
Hypertrophic cardiomyopathy (HCM) is the most common genetic heart disease. While ?50% of patients with HCM carry a sarcomere gene mutation (sarcomere mutation-positive, HCMSMP), the genetic background is unknown in the other half of the patients (sarcomere mutation-negative, HCMSMN). Genotype-specific differences have been reported in cardiac function. Moreover, HCMSMN patients have later disease onset and a better prognosis than HCMSMP patients. To define if genotype-specific derailments at the protein level may explain the heterogeneity in disease development, we performed a proteomic analysis in cardiac tissue from a clinically well-phenotyped HCM patient group.Methods
A proteomics screen was performed in cardiac tissue from 39 HCMSMP patients, 11HCMSMN patients, and 8 nonfailing controls. Patients with HCM had obstructive cardiomyopathy with left ventricular outflow tract obstruction and diastolic dysfunction. A novel MYBPC32373insG mouse model was used to confirm functional relevance of our proteomic findings.Results
In all HCM patient samples, we found lower levels of metabolic pathway proteins and higher levels of extracellular matrix proteins. Levels of total and detyrosinated ?-tubulin were markedly higher in HCMSMP than in HCMSMN and controls. Higher tubulin detyrosination was also found in 2 unrelated MYBPC3 mouse models and its inhibition with parthenolide normalized contraction and relaxation time of isolated cardiomyocytes.Conclusions
Our findings indicate that microtubules and especially its detyrosination contribute to the pathomechanism of patients with HCMSMP. This is of clinical importance since it represents a potential treatment target to improve cardiac function in patients with HCMSMP, whereas a beneficial effect may be limited in patients with HCMSMN.
SUBMITTER: Schuldt M
PROVIDER: S-EPMC7819533 | biostudies-literature | 2021 Jan
REPOSITORIES: biostudies-literature
Schuldt Maike M Pei Jiayi J Harakalova Magdalena M Dorsch Larissa M LM Schlossarek Saskia S Mokry Michal M Knol Jaco C JC Pham Thang V TV Schelfhorst Tim T Piersma Sander R SR Dos Remedios Cris C Dalinghaus Michiel M Michels Michelle M Asselbergs Folkert W FW Moutin Marie-Jo MJ Carrier Lucie L Jimenez Connie R CR van der Velden Jolanda J Kuster Diederik W D DWD
Circulation. Heart failure 20210112 1
<h4>Background</h4>Hypertrophic cardiomyopathy (HCM) is the most common genetic heart disease. While ≈50% of patients with HCM carry a sarcomere gene mutation (sarcomere mutation-positive, HCM<sub>SMP</sub>), the genetic background is unknown in the other half of the patients (sarcomere mutation-negative, HCM<sub>SMN</sub>). Genotype-specific differences have been reported in cardiac function. Moreover, HCM<sub>SMN</sub> patients have later disease onset and a better prognosis than HCM<sub>SMP</ ...[more]