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GRK5 is a regulator of fibroblast activation and cardiac fibrosis
- Source :
- Proceedings of the National Academy of Sciences of the United States of America
- Publication Year :
- 2021
- Publisher :
- Proceedings of the National Academy of Sciences, 2021.
-
Abstract
- Significance Pathological remodeling of the heart is a hallmark of chronic heart failure (HF) and these structural changes further perpetuate the disease. G protein-coupled receptor (GPCR) kinase 5 (GRK5) has been shown to cause deleterious effects on the cardiomyocyte during HF; however, its effects in cardiac fibroblasts, the crucial cell type responsible for maintaining the structural integrity of the heart, is not understood. Here, we use in vitro and in vivo methods to demonstrate that inhibition of GRK5 inhibits fibroblast activation and attenuates the fibrotic response in the heart.<br />Pathological remodeling of the heart is a hallmark of chronic heart failure (HF) and these structural changes further perpetuate the disease. Cardiac fibroblasts are the critical cell type that is responsible for maintaining the structural integrity of the heart. Stress conditions, such as a myocardial infarction (MI), can activate quiescent fibroblasts into synthetic and contractile myofibroblasts. G protein-coupled receptor kinase 5 (GRK5) is an important mediator of cardiovascular homeostasis through dampening of GPCR signaling, and is expressed in the heart and up-regulated in human HF. Of note, GRK5 has been demonstrated to translocate to the nucleus in cardiomyocytes in a calcium-calmodulin (Ca2+-CAM)-dependent manner, promoting hypertrophic gene transcription through activation of nuclear factor of activated T cells (NFAT). Interestingly, NFAT is also involved in fibroblast activation. GRK5 is highly expressed and active in cardiac fibroblasts; however, its pathophysiological role in these crucial cardiac cells is unknown. We demonstrate using adult cardiac fibroblasts that genetic deletion of GRK5 inhibits angiotensin II (AngII)-mediated fibroblast activation. Fibroblast-specific deletion of GRK5 in mice led to decreased fibrosis and cardiac hypertrophy after chronic AngII infusion or after ischemic injury compared to nontransgenic littermate controls (NLCs). Mechanistically, we show that nuclear translocation of GRK5 is involved in fibroblast activation. These data demonstrate that GRK5 is a regulator of fibroblast activation in vitro and cardiac fibrosis in vivo. This adds to previously published data which demonstrate the potential beneficial effects of GRK5 inhibition in the context of cardiac disease.
- Subjects :
- G-Protein-Coupled Receptor Kinase 5
Medical Sciences
Cardiac fibrosis
Myocardial Ischemia
heart failure
Cardiomegaly
GRK5
Models, Biological
Fibrosis
Animals
Medicine
Myofibroblasts
Receptor
Fibroblast
Mice, Knockout
Multidisciplinary
business.industry
Angiotensin II
Myocardium
fibrosis
NFAT
Biological Sciences
Fibroblasts
medicine.disease
Rats
Cell biology
medicine.anatomical_structure
Animals, Newborn
Heart failure
Cell Transdifferentiation
cardiovascular system
business
Myofibroblast
Subjects
Details
- ISSN :
- 10916490 and 00278424
- Volume :
- 118
- Database :
- OpenAIRE
- Journal :
- Proceedings of the National Academy of Sciences
- Accession number :
- edsair.doi.dedup.....a1a5ee8fdc73ab607430f87a8f748fb4