Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P15088 (mast cell)
 14,925 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The present study tested the hypothesis that cardiac mast cells and chymase are associated with matrix metalloproteinase (MMP) activation and extracellular matrix (ECM) degradation in the evolution of left ventricular (LV) chamber remodeling secondary to experimental mitral regurgitation (MR) in dogs. LV mast cell density, chymase activity, and angiotensin II (ANG II) levels were significantly increased 2 and 4 weeks post-MR, while an increase in angiotensin-converting enzyme (ACE) activity was not seen prior to the chronic 24 week stage. As early as 2 and 4 weeks, there was a significant decrease in interstitial myocardial collagen content that was associated with an increase in LV end-diastolic diameter (LVEDD) but a normal LVEDD/wall thickness ratio. While mast cell density decreased to normal at 24 weeks, both chymase and MMP-2 activity remained increased throughout the entire 24-week period post-MR. By 24 weeks a transition to an adverse pattern of LV remodeling characterized by a 2-fold increase in the LVEDD/wall thickness ratio had occurred. Thus, this study supports the hypothesis that mast cells and chymase are important modulators of MMP activity and ECM degradation, contributing to adverse LV remodeling in chronic volume overload secondary to MR.
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PMID:Cardiac mast cell- and chymase-mediated matrix metalloproteinase activity and left ventricular remodeling in mitral regurgitation in the dog. 1267 46

The chronic elevation in ventricular wall stress secondary to ventricular volume or pressure overload leads to structural remodeling of the muscular, vascular and extracellular matrix components of the myocardium. While initially a compensatory response, the progressive hypertrophy and ventricular dilatation induced by this condition ultimately have a detrimental effect on ventricular function, resulting in heart failure. Fibrillar collagen provides the skeletal framework which interconnects the cardiomyocytes, thereby maintaining ventricular shape and size and contributing to tissue stiffness. Accordingly, these myocardial collagen fibers must be disrupted for ventricular dilatation, sphericalization and wall thinning to occur. The presence of an abundant, latent matrix metalloproteinase (MMP) population which coexists with myocardial fibrillar collagen has been documented. Thus, the potential for collagen degradation to exceed synthesis exists should there be significant activation of this latent MMP system. Mast cells are known to store and release a variety of biologically active mediators including TNF-alpha and proteases such as tryptase and chymase, which can induce MMP activation. Increased cardiac mast cell density has been implicated in the pathophysiology of human end-stage cardiomyopathy and experimental myocardial infarction, hypertension and chronic volume overload secondary to mitral regurgitation and aorto-caval fistula. The potential role of cardiac mast cells in activating MMPs, which then results in fibrillar collagen degradation and adverse myocardial remodeling secondary to chronic volume and pressure overload will be the subject of this review.
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PMID:Cardiac mast cell regulation of matrix metalloproteinase-related ventricular remodeling in chronic pressure or volume overload. 1637 24

Increased numbers of mast cells have been reported in explanted human hearts with dilated cardiomyopathy and in animal models of experimentally induced hypertension, myocardial infarction, and chronic volume overload secondary to aortocaval fistula and mitral regurgitation. Accordingly, mast cells have been implicated to have a major role in the pathophysiology of these cardiovascular disorders. In vitro studies have verified that mast cell proteases are capable of activating collagenase, gelatinases and stromelysin. Recent results have shown that with chronic ventricular volume overload, there is an elevation in mast cell density, which is associated with a concomitant increase in matrix metalloproteinase (MMP) activity and extracellular matrix degradation. However, the role of the cardiac mast cell is not one dimensional, with evidence from hypertension and cardiac transplantation studies suggesting that they can also assume a pro-fibrotic phenotype in the heart. These adverse events do not occur in mast cell deficient rodents or when cardiac mast cells are pharmacologically prevented from degranulating. This review is focused on the regulation and dual roles of cardiac mast cells in: (i) activating MMPs and causing myocardial fibrillar collagen degradation and (ii) causing fibrosis in the stressed, injured or diseased heart. Moreover, there is strong evidence that premenopausal female cardioprotection may at least partly be due to gender differences in cardiac mast cells. This too will be addressed.
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PMID:Cardiac mast cells: the centrepiece in adverse myocardial remodelling. 2073 39