About this Research Topic
Cellular protein homeostasis or proteostasis is maintained by the orchestrated actions of intertwined cellular processes including protein synthesis, folding, quality control, trafficking, posttranslational modification, assembly/disassembly, localization, and degradation. The endoplasmic reticulum (ER) is involved in the synthesis, folding, quality control, and translocation of proteins targeted for the secretary pathway. The ER stress response, a cellular response to misfolded proteins specifically in the ER, is aimed at restoring proper protein folding to the ER and a return to proteostasis and cell survival. However, if the response is insufficient to restore proteostasis, continued activation of the ER stress response leads to cell death. Other complex response mechanisms have evolved to deal with unfolded protein stress in different subcellular compartments and their moderate activation is protective. Moreover, autophagy and the ubiquitin proteasome system (UPS) are pivotal to protein quality control and degradation in the cell. Abnormality in any of the processes regulating proteostasis can lead to the accumulation of unfolded, misfolded, or damaged proteins, causing cellular proteotoxicity that is clinically associated with many forms of disease, such as Parkinson’s, Huntington’s, and Alzheimer’s diseases, cancer, diabetes, Crohn’s disease as well as skeletal myopathies.
More recently, altered proteostasis has also been implicated in heart disease. Specifically, multiple acquired heart disorders such as cardiac hypertrophy and failure show ER stress, UPS dysregulation, and impaired autophagic flux. Moreover, several inherited cardiomyopathies are associated with activation of ER stress and disruption of autophagy and/or pathological protein aggregation. For example, hypertrophic cardiomyopathy is a hallmark of Danon disease, which is caused by loss of function mutations in the lysosome-associated membrane protein 2 (LAMP2) gene, essential for lysosome motility and lysosome-autophagosome fusion. Similarly, genetic mutations in desmin (DES) and several genes encoding desmin-accessory proteins such as cardiac myosin-binding protein C (MYBPC3), crystallin alpha B (CryAB), and lamin A (LMNA), cause marked UPS impairment followed by different forms of cardiomyopathies. Another significant field of protein degradation and/or protein quality control in the heart involves anti-cancer therapies. Several drugs such as tyrosine kinase inhibitors (e.g., imatinib), anthracyclines (e.g., doxorubicin) or proteasome inhibitors (e.g. bortezomib) can impair the UPS or autophagy and thereby cause clinically relevant side effects such as cardiomyopathy and heart failure. Thus, from a clinical standpoint, there is a need to further investigate the underlying molecular mechanisms of impaired proteostasis in order to develop innovative therapeutic approaches of cardiomyopathy and heart failure.
The present Research Topic is aimed to collect contributions that critically discuss the modulators and interactions of autophagy, unfolded protein responses, and the UPS pathways affecting cardiac function or homeostasis. We welcome original research and review articles on the following themes:
• Role of autophagy, unfolded protein responses, and the UPS in cardiac function and diseases
• Role of known/novel factors (e.g., a gene/transcription factor/microRNA/lncRNA/small molecule, post-translational modifications, etc.) regulating cardiac autophagy/unfolded protein responses/UPS
• Translational/therapeutic approaches to improve cardiac disease condition via targeting cardiac proteostasis
More recently, altered proteostasis has also been implicated in heart disease. Specifically, multiple acquired heart disorders such as cardiac hypertrophy and failure show ER stress, UPS dysregulation, and impaired autophagic flux. Moreover, several inherited cardiomyopathies are associated with activation of ER stress and disruption of autophagy and/or pathological protein aggregation. For example, hypertrophic cardiomyopathy is a hallmark of Danon disease, which is caused by loss of function mutations in the lysosome-associated membrane protein 2 (LAMP2) gene, essential for lysosome motility and lysosome-autophagosome fusion. Similarly, genetic mutations in desmin (DES) and several genes encoding desmin-accessory proteins such as cardiac myosin-binding protein C (MYBPC3), crystallin alpha B (CryAB), and lamin A (LMNA), cause marked UPS impairment followed by different forms of cardiomyopathies. Another significant field of protein degradation and/or protein quality control in the heart involves anti-cancer therapies. Several drugs such as tyrosine kinase inhibitors (e.g., imatinib), anthracyclines (e.g., doxorubicin) or proteasome inhibitors (e.g. bortezomib) can impair the UPS or autophagy and thereby cause clinically relevant side effects such as cardiomyopathy and heart failure. Thus, from a clinical standpoint, there is a need to further investigate the underlying molecular mechanisms of impaired proteostasis in order to develop innovative therapeutic approaches of cardiomyopathy and heart failure.
The present Research Topic is aimed to collect contributions that critically discuss the modulators and interactions of autophagy, unfolded protein responses, and the UPS pathways affecting cardiac function or homeostasis. We welcome original research and review articles on the following themes:
• Role of autophagy, unfolded protein responses, and the UPS in cardiac function and diseases
• Role of known/novel factors (e.g., a gene/transcription factor/microRNA/lncRNA/small molecule, post-translational modifications, etc.) regulating cardiac autophagy/unfolded protein responses/UPS
• Translational/therapeutic approaches to improve cardiac disease condition via targeting cardiac proteostasis
Keywords: Proteostasis, Cardiac Disease, Health Autophagy, UPR, ER
Important Note: All contributions to this Research Topic must be within the scope of the section and journal to which they are submitted, as defined in their mission statements. Frontiers reserves the right to guide an out-of-scope manuscript to a more suitable section or journal at any stage of peer review.
