FRI118 3D Reconstruction Of Mitochondria From Human Heart Failure Structures Is Associated With Alterations In CHCHD6 And CHCHD3 Expression

Abstract

Abstract Disclosure: A.G. Marshall: None. Z. Vue, PhD: None. E. Garza-Lopez: None. H. Beasley, PhD: None. V. Exil: None. K. Actkins: None. T. Miller-Fleming: None. A.O. Hinton: None. Heart failure (HF) is accompanied by symptoms and signs caused by cardiac dysfunction, resulting in reduced longevity. Critically, HF has been associated with mitochondria dysfunction, causing pathophysiology that might contribute to age-dependent decrease in cardiac function. Thus, we hypothesize that reduced cardiac function in response to HF, affects mitochondrial function and morphology. To test this, we investigated mitochondrial morphological changes using 3D reconstruction from 4 control human hearts and 4 human heart failure patients. Mitochondrial samples were 3D rendered and quantified using serial block facing-scanning electron microscopy and the Amira software. From our HF reconstructions, there are many phenotypes, including fragmentation, nanotunnels, and mitochondrial clustering, compared to controls, which may be associated to mitochondrial dysfunction. Surprisingly, we saw altered expression of CHCHD6 and CHCHD3 in human heart failure samples, based on immunofluorescence. Thus, we knocked out CHCHD6 and CHCHD3 in mouse fibroblasts, myotubes and human-induced pluripotent stem cell-derived cardiomyocytes and saw fragmentation in all three models. Presently, HF represents an unmet need with no approved clinical therapies for damaged myocardium replacement. Here, we suggest that CHCHD3 and CHCHD6 may be a molecular target that functions in the development of HF and possibly develop novel therapeutics for the treatment of HF. Presentation: Friday, June 16, 2023