Aims: Although current clinical therapies following myocardial infarction have improved patient outcomes, morbidity, and mortality rates secondary to ischemic and ischemia reperfusion (IR) injury remains high. Maintaining mitochondrial quality is essential to limit myocardial damage following cardiac ischemia and IR injury. The mitochondrial deacetylase sirtuin 3 (SIRT3) plays a pivotal role in regulating mitochondrial function and cardiac energy metabolism.
View Article and Find Full Text PDFAortic aneurysm is a potentially deadly disease. It is chronic degeneration of the aortic wall that involves an inflammatory response and the immune system, aberrant remodelling of the extracellular matrix, and maladaptive transformation of the aortic cells. This review article focuses on the role of the inflammatory cells in abdominal aortic aneurysm.
View Article and Find Full Text PDFAm J Physiol Heart Circ Physiol
October 2024
Atherosclerosis is commonly known as an inflammatory disease that is characterized by lipid deposition in the arterial wall, causing gradual restriction or complete blockade of blood flow, which can cause complications such as myocardial infarction, stroke, or peripheral artery disease. Several factors contribute to initiation and progression of atherosclerotic plaque formation. The role of macrophages and leukocytes in atherosclerosis has been well explored.
View Article and Find Full Text PDFAm J Physiol Heart Circ Physiol
August 2024
Aims: Aorta exhibits regional heterogeneity (structural and functional), while different etiologies for thoracic and abdominal aortic aneurysm (TAA, AAA) are recognized. Tissue inhibitor of metalloproteinases (TIMPs) regulate vascular remodeling through different mechanisms. Region-dependent functions have been reported for TIMP3 and TIMP4 in vascular pathologies.
View Article and Find Full Text PDFHeart transplant and recipient survival are limited by immune cell-mediated injury of the graft vasculature. We examined the role of the phosphoinositide 3-kinase-β (PI3Kβ) isoform in endothelial cells (EC) during coronary vascular immune injury and repair in mice. In minor histocompatibility-antigen mismatched allogeneic heart grafts, a robust immune response was mounted to each wild-type, PI3Kβ inhibitor-treated, or endothelial-selective PI3Kβ knockout (ECβKO) graft transplanted to wild-type recipients.
View Article and Find Full Text PDFAm J Physiol Heart Circ Physiol
December 2022
Myocardial pathologies resulting from SARS-CoV-2 infections are consistently rising with mounting case rates and reinfections; however, the precise global burden is largely unknown and will have an unprecedented impact. Understanding the mechanisms of COVID-19-mediated cardiac injury is essential toward the development of cardioprotective agents that are urgently needed. Assessing novel therapeutic strategies to tackle COVID-19 necessitates an animal model that recapitulates human disease.
View Article and Find Full Text PDFAm J Physiol Heart Circ Physiol
December 2022
Myocardial ischemic injury and its resolution are the key determinants of morbidity or mortality in heart failure. The cause and duration of ischemia in patients vary. Numerous experimental models and methods have been developed to define genetic, metabolic, molecular, cellular, and pathophysiological mechanisms, in addition to defining structural and functional deterioration of cardiovascular performance.
View Article and Find Full Text PDFBackground: Myocardial hypertrophy and dilation are key features of cardiomyopathies and involve several cellular and molecular events. ADAMs (a disintegrin and metalloproteinases) are membrane-bound proteinases with diverse functions whose role in heart disease remains underexplored. ADAM15 is expressed in the heart and is downregulated in the failing human heart.
View Article and Find Full Text PDFAims: In response to pro-fibrotic signals, scleraxis regulates cardiac fibroblast activation in vitro via transcriptional control of key fibrosis genes such as collagen and fibronectin; however, its role in vivo is unknown. The present study assessed the impact of scleraxis loss on fibroblast activation, cardiac fibrosis, and dysfunction in pressure overload-induced heart failure.
Methods And Results: Scleraxis expression was upregulated in the hearts of non-ischemic dilated cardiomyopathy patients, and in mice subjected to pressure overload by transverse aortic constriction (TAC).
Am J Physiol Heart Circ Physiol
October 2022
Endotoxemia elicits a multiorgan inflammatory response that results in cardiac dysfunction and often leads to death. Inflammation-induced metabolism of endogenous N-3 and N-6 polyunsaturated fatty acids generates numerous lipid mediators, such as epoxy fatty acids (EpFAs), which protect the heart. However, EpFAs are hydrolyzed by soluble epoxide hydrolase (sEH), which attenuates their cardioprotective actions.
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September 2022
Genetically modified mice are widely used to recapitulate human diseases. Atherosclerosis can be induced in mice with low-density lipoprotein receptor ()-deficiency and a high-fat diet (HFD). Disintegrin and metalloproteinase-17 (ADAM17) in the smooth muscle cell (SMC) contribute to vascular pathologies, and hence its role in atherosclerosis was investigated.
View Article and Find Full Text PDFArterioscler Thromb Vasc Biol
July 2022
Aortic aneurysm is a complex pathology that can be lethal if not detected in time. Although several molecular mechanisms and pathways have been identified to be involved in aortic aneurysm development and growth, the current lack of an effective pharmacological treatment highlights the need for a more thorough understanding of the factors that regulate the remodeling of the aortic wall in response to triggers that lead to aneurysm formation. This task is further complicated by the regional heterogeneity of the aorta and that thoracic and abdominal aortic aneurysm are distinct pathologies with different risk factors and distinct course of progression.
View Article and Find Full Text PDFCollagen cross-linking is an important step in optimal scar formation. Myocardial infarction (MI) results in loss of cardiomyocytes that are replaced with a scar (infarct) tissue. Disintegrin and metalloproteinases (ADAMs) are membrane-bound proteases that can interact with molecules intra- and extra-cellularly to mediate various cellular functions.
View Article and Find Full Text PDFACE (angiotensin-converting enzyme)-2 as the target for SARS-CoV-2 also negatively regulates the renin-angiotensin system. Pathological activation of ADAM17 (A disintegrin and metalloproteinase-17) may potentiate inflammation and diminish ACE2-mediated tissue protection through proteolytic shedding, contributing to SARS-CoV-2 pathogenesis. We aim to examine plasma soluble ACE2 and angiotensin profiles in relation to outcomes by enrolling consecutive patients admitted for COVID-19 with baseline blood collection at admission and repeated sampling at 7 days.
View Article and Find Full Text PDFThe extracellular matrix (ECM) plays important roles in maintaining physiological structure and functions of various tissues and organs. Cardiac fibrosis is the excess deposition of ECM, including both fibrillar (collagens I and III) and non-fibrillar proteins. Characteristics of fibrosis can vary depending on the pathology, with focal fibrosis occurring following myocardial infarction (MI), and diffuse interstitial and perivascular fibrosis mainly in non-ischemic heart diseases.
View Article and Find Full Text PDFAged males disproportionately succumb to increased COVID-19 severity, hospitalization, and mortality compared to females. Angiotensin-converting enzyme 2 (ACE2) and transmembrane protease, serine 2 (TMPRSS2) facilitate SARS-CoV-2 viral entry and may have sexually dimorphic regulation. As viral load dictates disease severity, we investigated the expression, protein levels, and activity of ACE2 and TMPRSS2.
View Article and Find Full Text PDFAm J Physiol Heart Circ Physiol
December 2021