Modulation of P2Y6R expression exacerbates pressure overload-induced cardiac remodeling in mice

Abstract

Cardiac tissue remodeling caused by hemodynamic overload is a major clinical outcome of heart failure. Uridine-responsive purinergic P2Y 6 receptor (P2Y 6 R) contributes to the progression of cardiovascular remodeling in rodents, but it is not known whether inhibition of P2Y 6 R prevents or promotes heart failure. We demonstrate that inhibition of P2Y 6 R promotes pressure overload-induced sudden death and heart failure in mice. In neonatal cardiomyocytes, knockdown of P2Y 6 R significantly attenuated hypertrophic growth and cell death caused by hypotonic stimulation, indicating the involvement of P2Y 6 R in mechanical stress-induced myocardial dysfunction. Unexpectedly, compared with wild-type mice, deletion of P2Y 6 R promoted pressure overload-induced sudden death, as well as cardiac remodeling and dysfunction. Mice with cardiomyocyte-specific overexpression of P2Y 6 R also exhibited cardiac dysfunction and severe fibrosis. In contrast, P2Y 6 R deletion had little impact on oxidative stress-mediated cardiac dysfunction induced by doxorubicin treatment. These findings provide overwhelming evidence that systemic inhibition of P2Y 6 R exacerbates pressure overloadinduced heart failure in mice, although P2Y 6 R in cardiomyocytes contributes to the progression of cardiac fibrosis. Cardiac remodeling is characterized by structural and morphological changes of the heart, including hypertrophy and fibrosis, and is a major clinical outcome of heart failure after cardiac injury 1,2. Structural remodeling is thought to be a plasticity process of the heart to overcome hemodynamic overload, but cardiac resistance (i.e., robustness) to mechanical stress may be reduced by additional environmental factors, such as physical and chemical stresses 3. Purinergic receptors are activated by extracellular nucleotides and play important roles in cardiovascular physiology and pathophysiology 4. Purinergic receptors are divided into two main groups, P1 and P2. P1 receptors are activated by adenosine, and mediate cardiodepressant and cardioprotective effects 4. P2 receptors are subdivided into P2X and P2Y subfamilies, which consist of ligand-gated ion channels and G protein coupled receptors (GPCRs), respectively 4. The P2Y family has eight subtypes (P2Y 1 , P2Y 2 , P2Y 4 , P2Y 6 , P2Y 11 , P2Y 12 , P2Y 13 and P2Y 14) that differ in their coupling G protein and ligand selectivity 5. Purinergic signaling must be important for cardiovascular homeostasis because many purinergic receptors are expressed in human and mouse hearts 6,7. The nucleotide, uridine triphosphate (UTP), induces a profibrotic response via P2Y 2 R 8 , while adenosine triphosphate (ATP) induces contraction 9 and negatively regulates hypertrophic growth of cardiomyocytes 10,11 .

Cardiovascular Disease in Duchenne Muscular Dystrophy

“… 76 , 77 In pressure overload–induced fibrosis in murine models, the G-protein coupled P2Y6 receptor activation by extracellular purine stimulation leads to cardiac fibrosis. 78 , 79 In mdx mouse models of DMD, increased purine metabolism has been noted with involvement of G-protein coupled (P2Y2) and non–G-protein coupled (P2X7) purinergic receptors. 80 P2X7 contributes to up-regulation of IL-1β and NLRP3 inflammasome activation.…”

Redox-dependent internalization of the purinergic P2Y 6 receptor limits colitis progression

“…Cigarette smoke, which includes several kinds of electrophilic aldehydes, reportedly has some beneficial effect on the prevention of IBD progression (42), as does the administration of natural ITCs (43). Moreover, P2Y 6 R is involved in many diseases such as those of the cardiovascular system (44)(45)(46)(47), obesity (48,49), and neurodegenerative disorders (50). The nucleophilic thiol group of cysteine mediates various posttranslational modifications such as lipidation and oxidation and can be an attractive target for drug design.…”

“…85–23, revised 1996) and were approved by the ethics committees at National Institute for Physiological Sciences or the Animal Care and Use Committee, Kyushu University. P2ry6 −/− mice (a gift from B. Robaye, Université Libre de Bruxelles) were backcrossed onto C57BL/6J mice background as described previously ( 44 , 45 ). We also generated P2ry6 −/− mice using CRISPR-Cas9 and confirmed that the apparent phenotype was equivalent to the gifted P2ry6 −/− mice.…”

“…Plasmid construction P2Y 6 R and AT1R plasmids were described in a previous study (44). Point mutations of plasmids were generated by sitedirected polymerase chain reaction (PCR) mutagenesis.…”

P2 Receptors in Cardiac Myocyte Pathophysiology and Mechanotransduction

“…Mice with cardiomyocyte-specific overexpression of P2Y6 receptor also exhibited cardiac dysfunction and severe fibrosis. In contrast, P2Y6 receptor deletion had little impact on oxidative stress-mediated cardiac dysfunction induced by doxorubicin treatment [ 171 ].…”