Gene expression associated with the autophagy process in patient’s myocardium with hypertrophic cardiomyopathy of various genetic etiology

The most common type of cardiomyopathy is hypertrophic cardiomyopathy (HCM), determined by wall thickening of the left ventricle. Most often the reason of this type of cardiomyopathy are mutations in genes encoding sarcomere proteins. However, in most cases it is not possible to establish a clear cause of the development of HCMP due to the absence of mutations of causal genes. The development of pronounced myocardial hypertrophy stimulated investigation of intracellular processes of maintaining homeostasis, in particular autophagy. Being one of the main mechanisms of protein quality control in muscle cells, at the impairment of autophagy was previously discussed in the presence of sarcomere proteins mutations. This work is focused on studying expression changes among main biochemical markers associated with the autophagy process in myocardial tissue samples obtained from patients with diagnosed HCMP. The study group of patients was divided into several subgroups to compare the results obtained depending on the mutation found. It was found that the expression of autophagy markers and mitochondrial homeostasis in patients with HCMP associated with the presence of sarcomere mutations differed from the expression of these genes relative to the comparison group. While in the samples from patients with Z-disk genes mutations, as well as in the genes encoding lysosomal enzymes, no expression changes of the studied autophagy markers were found.

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