1. Proteomic and Functional Studies Reveal Detyrosinated Tubulin as Treatment Target in Sarcomere Mutation-Induced Hypertrophic Cardiomyopathy.
- Author
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Schuldt, Maike, Pei, Jiayi, Harakalova, Magdalena, Dorsch, Larissa M., Schlossarek, Saskia, Mokry, Michal, Knol, Jaco C., Pham, Thang V., Schelfhorst, Tim, Piersma, Sander R., dos Remedios, Cris, Dalinghaus, Michiel, Michels, Michelle, Asselbergs, Folkert W., Moutin, Marie-Jo, Carrier, Lucie, Jimenez, Connie R., van der Velden, Jolanda, and Kuster, Diederik W. D.
- 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 a-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. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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