SciCombinator

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Journal: Arteriosclerosis, thrombosis, and vascular biology

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OBJECTIVE: To test whether equivalent energy expenditure by moderate-intensity (eg, walking) and vigorous-intensity exercise (eg, running) provides equivalent health benefits.Approach and Results-We used the National Runners' (n=33 060) and Walkers' (n=15 945) Health Study cohorts to examine the effect of differences in exercise mode and thereby exercise intensity on coronary heart disease (CHD) risk factors. Baseline expenditure (metabolic equivant hours per day [METh/d]) was compared with self-reported, physician-diagnosed incident hypertension, hypercholesterolemia, diabetes mellitus, and CHD during 6.2 years follow-up. Running significantly decreased the risks for incident hypertension by 4.2% (P<10(-7)), hypercholesterolemia by 4.3% (P<10(-14)), diabetes mellitus by 12.1% (P<10(-5)), and CHD by 4.5% per METh/d (P=0.05). The corresponding reductions for walking were 7.2% (P<10(-7)), 7.0% (P<10(-8)), 12.3% (P<10(-4)), and 9.3% (P=0.01). Relative to <1.8 METh/d, the risk reductions for 1.8 to 3.6, 3.6 to 5.4, 5.4 to 7.2, and ≥7.2 METh/d were as follows: (1) 10.0%, 17.7%, 25.1%, and 34.9% from running and 14.0%, 23.8%, 21.8%, and 38.3% from walking for hypercholesterolemia; (2) 19.7%, 19.4%, 26.8%, and 39.8% from running and 14.7%, 19.1%, 23.6%, and 13.3% from walking for hypertension; and (3) 43.5%, 44.1%, 47.7%, and 68.2% from running, and 34.1%, 44.2% and 23.6% from walking for diabetes mellitus (walking >5.4 METh/d excluded for too few cases). The risk reductions were not significantly different for running than walking for diabetes mellitus (P=0.94), hypercholesterolemia (P=0.06), or CHD (P=0.26), and only marginally greater for walking than running for hypercholesterolemia (P=0.04). CONCLUSIONS: Equivalent energy expenditures by moderate (walking) and vigorous (running) exercise produced similar risk reductions for hypertension, hypercholesterolemia, diabetes mellitus, and possibly CHD.

Concepts: Cushing's syndrome, Stroke, Metabolic syndrome, Hypercholesterolemia, Obesity, Myocardial infarction, Diabetes mellitus, Hypertension

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Aberrant neutrophil activation occurs during the advanced stages of atherosclerosis. Once primed, neutrophils can undergo apoptosis or release neutrophil extracellular traps. This extracellular DNA exerts potent proinflammatory, prothrombotic, and cytotoxic properties. The goal of this study was to examine the relationships among extracellular DNA formation, coronary atherosclerosis, and the presence of a prothrombotic state.

Concepts: Monocyte, Atherosclerosis, Macrophage

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Aldosterone (Aldo) is involved in arterial stiffness and heart failure, but the mechanisms have remained unclear. Galectin-3 (Gal-3), a β-galactoside-binding lectin, plays an important role in inflammation, fibrosis, and heart failure. We investigated here whether Gal-3 is involved in Aldo-induced vascular fibrosis.

Concepts: Cholesterol, Heart, Aldosterone, Blood pressure, Blood vessel

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OBJECTIVE: Calcific aortic valve disease (CAVD) is a major public health problem with no effective treatment available other than surgery. We previously showed that mature heart valves calcify in response to retinoic acid (RA) treatment through downregulation of the SRY transcription factor Sox9. In this study, we investigated the effects of excess vitamin A and its metabolite RA on heart valve structure and function in vivo and examined the molecular mechanisms of RA signaling during the calcification process in vitro. METHODS AND RESULTS: Using a combination of approaches, we defined calcific aortic valve disease pathogenesis in mice fed 200 IU/g and 20 IU/g of retinyl palmitate for 12 months at molecular, cellular, and functional levels. We show that mice fed excess vitamin A develop aortic valve stenosis and leaflet calcification associated with increased expression of osteogenic genes and decreased expression of cartilaginous markers. Using a pharmacological approach, we show that RA-mediated Sox9 repression and calcification is regulated by classical RA signaling and requires both RA and retinoid X receptors. CONCLUSIONS: Our studies demonstrate that excess vitamin A dietary intake promotes heart valve calcification in vivo. Therefore suggesting that hypervitaminosis A could serve as a new risk factor of calcific aortic valve disease in the human population.

Concepts: Gene, In vitro, Aortic valve, Retinol, Valves, Valvular heart disease, Aortic valve stenosis, Vitamin A

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Inhibitor of differention-3 (Id3) promotes B cells homing to the aorta and atheroprotection in Apoe(-/-) mice. We sought to determine the impact of loss of Id3 in the Ldlr((-/-)) mouse model of diet-induced atherosclerosis and identify novel Id3 targets in the vessel wall.

Concepts: Blood vessel, VCAM-1, Monocyte, Macrophage, Gene, Atherosclerosis

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Macrophage endothelial lipase (EL) is associated with increased atherosclerosis and inflammation. Because of their anti-inflammatory properties we hypothesized that n-3 fatty acids, in contrast to saturated fatty acids, would lower macrophages and arterial EL and inflammatory markers.

Concepts: Blood vessel, Saturated fat, Immune system, Fat, Omega-3 fatty acid, Anti-inflammatory, Inflammation, Atherosclerosis

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Transforming growth factor-β-activated kinase 1 (TAK1) is a mitogen-activated protein 3-kinase and an AMP-activated protein kinase (AMPK) kinase in some cell types. Although TAK1(-/-) mice display defects in developmental vasculogenesis, the role of TAK1 in endothelial cells has not been investigated in detail.

Concepts: Protein kinase A, Endothelium, Protein kinases, Signal transduction, Gene, Angiogenesis, Enzyme, Adenosine triphosphate

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Myocardin, a potent transcriptional coactivator of serum response factor, is involved in vascular development and promotes a contractile smooth muscle phenotype. Myocardin levels are reduced during vascular injury, in association with phenotypic switching of smooth muscle cells (SMCs). However, the direct role of myocardin in vascular disease is unclear.

Concepts: Muscular system, Growth factor, Smooth muscle, Transcription factor, Actin, Cardiac muscle, Muscle contraction, Gene

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Inflammation is essential to combat invading microbial pathogens. In this process, the involvement of multiple immune cell populations is crucial in mounting an optimum immune response. In the past decade, a new class of noncoding small RNAs, called microRNAs (miRNAs), has emerged as important regulators in biological processes. The important role of miRNAs in inflammation and immune response is highlighted by studies in which deregulation of miRNAs was demonstrated to accompany diseases associated with excessive or uncontrolled inflammation. In this brief review, we summarize the roles of miRNAs that have been characterized in innate and adaptive immune responses. We discuss the role of miRNAs in macrophage polarization, a molecular event that has clear effect on inflammation.

Concepts: DNA, Organism, Adaptive immune system, Monocyte, Gene, Bacteria, Immune system

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Iron and the iron regulatory hormone hepcidin, major determinant of body iron distribution, are hypothesized to play a role in cardiovascular disease. Here, we assess the associations of hepcidin as well as ferritin, iron, total iron-binding capacity, and transferrin saturation (ie, iron parameters) with noninvasive measurements of atherosclerosis in men and women of a population-based cohort.

Concepts: Gender role, Blood vessel, Cardiovascular disease, Serum iron, Transferrin, Total iron-binding capacity, Transferrin saturation, Iron metabolism