AJP: Heart and Circulatory Physiology This is an RSS file. You can use it to subscribe to this data in your favourite RSS reader or to display this data on your own website or blog.

Aerobic exercise in anthracycline-induced cardiotoxicity: a systematic review of current evidence and future directions
Cancer and cardiovascular disease are major causes of morbidity and mortality worldwide. Older cancer patients often wrestle with underlying heart disease during cancer therapy, whereas childhood cancer survivors are living long enough to face long-term unintended cardiac consequences of cancer therapies, including anthracyclines. Although effective and widely used, particularly in the pediatric population, anthracycline-related side effects including dose-dependent association with cardiac dysfunction limit their usage. Currently, there is only one United States Food and Drug Administration-approved drug, dexrazoxane, ava...
Source: AJP: Heart and Circulatory Physiology - January 31, 2017 Category: Cardiology Authors: Chen, J. J., Wu, P.-T., Middlekauff, H. R., Nguyen, K.-L. Tags: Special Review Articles Source Type: research

Retinal microvascular network alterations: potential biomarkers of cerebrovascular and neural diseases
Increasing evidence suggests that the conditions of retinal microvessels are indicators to a variety of cerebrovascular, neurodegenerative, psychiatric, and developmental diseases. Thus noninvasive visualization of the human retinal microcirculation offers an exceptional opportunity for the investigation of not only the retinal but also cerebral microvasculature. In this review, we show how the conditions of the retinal microvessels could be used to assess the conditions of brain microvessels because the microvascular network of the retina and brain share, in many aspects, standard features in development, morphology, func...
Source: AJP: Heart and Circulatory Physiology - January 31, 2017 Category: Cardiology Authors: Cabrera DeBuc, D., Somfai, G. M., Koller, A. Tags: Call for Papers: Small Vessels Big Problems REVIEW Source Type: research

Antihypertensive effects of peroxisome proliferator-activated receptor-{beta}/{delta} activation
Peroxisome proliferator-activated receptors (PPARs) are members of the nuclear hormone receptor superfamily of ligand-activated transcription factors, which is composed of three members encoded by distinct genes: PPARα, PPARβ/, and PPAR. The biological actions of PPARα and PPAR and their potential as a cardiovascular therapeutic target have been extensively reviewed, whereas the biological actions of PPARβ/ and its effectiveness as a therapeutic target in the treatment of hypertension remain less investigated. Preclinical studies suggest that pharmacological PPARβ/ activation induces antihyperten...
Source: AJP: Heart and Circulatory Physiology - January 31, 2017 Category: Cardiology Authors: Toral, M., Romero, M., Perez-Vizcaino, F., Duarte, J., Jimenez, R. Tags: Call for Papers: Small Vessels Big Problems REVIEW Source Type: research

Interruption of perivascular sympathetic nerves of cerebral arteries offers neuroprotection against ischemia
Sympathetic nervous system activity is increased after cardiopulmonary arrest, resulting in vasoconstrictor release from the perivascular sympathetic nerves of cerebral arteries. However, the pathophysiological function of the perivascular sympathetic nerves in the ischemic brain remains unclear. A rat model of global cerebral ischemia (asphyxial cardiac arrest, ACA) was used to investigate perivascular sympathetic nerves of cerebral arteries via bilateral decentralization (preganglionic lesion) of the superior cervical ganglion (SCG). Decentralization of the SCG 5 days before ACA alleviated hypoperfusion and afforded hipp...
Source: AJP: Heart and Circulatory Physiology - December 31, 2016 Category: Cardiology Authors: Lee, R. H., Couto e Silva, A., Lerner, F. M., Wilkins, C. S., Valido, S. E., Klein, D. D., Wu, C. Y., Neumann, J. T., Della-Morte, D., Koslow, S. H., Minagar, A., Lin, H. W. Tags: RAPID REPORT Source Type: research

Positive versus negative effects of VEGF165 on Ca2+ signaling and NO production in human endothelial cells
In this study, we seek to understand how VEGF165 influences vasodilator production via Ca2+ signaling mechanisms in human endothelial cells. We utilize human umbilical vein endothelial cells (HUVEC) as well as intact ex vivo human umbilical vein (HUV Endo) to address direct stimulation of Ca2+ and NO by VEGF165 alone, as well as the effect of VEGF165 on subsequent ATP-stimulated Ca2+ signaling and NO production. We show that VEGF165 stimulates Ca2+ responses in both HUVEC and HUV Endo, which results in a corresponding increase in NO production in HUV Endo. Longer-term VEGF165 pretreatment then inhibits sustained Ca2+ burst...
Source: AJP: Heart and Circulatory Physiology - December 31, 2016 Category: Cardiology Authors: Boeldt, D. S., Krupp, J., Yi, F.-X., Khurshid, N., Shah, D. M., Bird, I. M. Tags: RESEARCH ARTICLE Source Type: research

Investigating the extremes of the continuum of paracrine functions in CD34-/CD31+ CACs across diverse populations
Paracrine function of circulating angiogenic cells (CACs) is thought to contribute to vascular maintenance. We previously identified S100A8 and S100A9 secreted from physically inactive individuals’ CD34–/CD31+ CACs as negative regulators of capillary-like network formation. The purpose of this study was to investigate further the extremes of the continuum of CAC paracrine actions using two distinctly different groups representing "healthy" and "impaired" CAC function. We aimed to determine how capillary-like network formation in human umbilical vein endothelial cells (HUVECs) is affected by S100A8 and S100A9 in...
Source: AJP: Heart and Circulatory Physiology - December 31, 2016 Category: Cardiology Authors: Landers-Ramos, R. Q., Sapp, R. M., VandeWater, E., Macko, J., Robinson, S., Wang, Y., Chin, E. R., Spangenburg, E. E., Prior, S. J., Hagberg, J. M. Tags: RESEARCH ARTICLE Source Type: research

Hyperglycemia induces defective Ca2+ homeostasis in cardiomyocytes
Diabetes and other metabolic conditions characterized by elevated blood glucose constitute important risk factors for cardiovascular disease. Hyperglycemia targets myocardial cells rendering ineffective mechanical properties of the heart, but cellular alterations dictating the progressive deterioration of cardiac function with metabolic disorders remain to be clarified. In the current study, we examined the effects of hyperglycemia on cardiac function and myocyte physiology by employing mice with high blood glucose induced by administration of streptozotocin, a compound toxic to insulin-producing β-cells. We found tha...
Source: AJP: Heart and Circulatory Physiology - December 31, 2016 Category: Cardiology Authors: Sorrentino, A., Borghetti, G., Zhou, Y., Cannata, A., Meo, M., Signore, S., Anversa, P., Leri, A., Goichberg, P., Qanud, K., Jacobson, J. T., Hintze, T. H., Rota, M. Tags: RESEARCH ARTICLE Source Type: research

Cardiomyopathy-related mutation (A30V) in mouse cardiac troponin T divergently alters the magnitude of stretch activation in {alpha}- and {beta}-myosin heavy chain fibers
The present study investigated the functional consequences of the human hypertrophic cardiomyopathy (HCM) mutation A28V in cardiac troponin T (TnT). The A28V mutation is located within the NH2 terminus of TnT, a region known to be important for full activation of cardiac thin filaments. The functional consequences of the A28V mutation in TnT remain unknown. Given how α- and β-myosin heavy chain (MHC) isoforms differently alter the functional effect of the NH2 terminus of TnT, we hypothesized that the A28V-induced effects would be differently modulated by α- and β-MHC isoforms. Recombinant wild-type mo...
Source: AJP: Heart and Circulatory Physiology - December 31, 2016 Category: Cardiology Authors: Mickelson, A. V., Gollapudi, S. K., Chandra, M. Tags: RESEARCH ARTICLE Source Type: research

Lifelong quercetin enrichment and cardioprotection in Mdx/Utrn+/- mice
Duchenne Muscular Dystrophy (DMD) is associated with progressive cardiac pathology; however, the SIRT1/PGC1-α activator quercetin may cardioprotect dystrophic hearts. We tested the extent to which long-term 0.2% dietary quercetin enrichment attenuates dystrophic cardiopathology in Mdx/Utrn+/– mice. At 2 mo, Mdx/Utrn+/– mice were fed quercetin-enriched (Mdx/Utrn+/–-Q) or control diet (Mdx/Utrn+/–) for 8 mo. Control C57BL/10 (C57) animals were fed a control diet for 10 mo. Cardiac function was quantified by MRI at 2 and 10 mo. Spontaneous physical activity was quantified during the last week of ...
Source: AJP: Heart and Circulatory Physiology - December 31, 2016 Category: Cardiology Authors: Ballmann, C., Denney, T. S., Beyers, R. J., Quindry, T., Romero, M., Amin, R., Selsby, J. T., Quindry, J. C. Tags: RESEARCH ARTICLE Source Type: research

Dynamical mechanisms of phase-2 early afterdepolarizations in human ventricular myocytes: insights from bifurcation analyses of two mathematical models
This study demonstrates that bifurcation analysis allows us to understand the dynamical mechanisms of EAD formation more profoundly. NEW & NOTEWORTHY We investigated mechanisms of phase-2 early afterdepolarization (EAD) by bifurcation analyses of human ventricular myocyte (HVM) models. EAD formation in paced HVMs basically depended on bifurcation phenomena in non-paced HVMs, but was strongly affected by intracellular ion concentrations in stationary and dynamic states. EAD generation did not necessarily require IKs. (Source: AJP: Heart and Circulatory Physiology)
Source: AJP: Heart and Circulatory Physiology - December 31, 2016 Category: Cardiology Authors: Kurata, Y., Tsumoto, K., Hayashi, K., Hisatome, I., Tanida, M., Kuda, Y., Shibamoto, T. Tags: RESEARCH ARTICLE Source Type: research

Estrogen receptor antagonism exacerbates cardiac structural and functional remodeling in female rats
We have previously demonstrated the cardioprotective effects of ovarian hormones against adverse ventricular remodeling imposed by chronic volume overload. Here, we assess the estrogen receptor dependence of this cardioprotection. Four groups of female rats were studied: sham-operated (Sham), volume overloaded [aortocaval fistula (ACF)], Sham treated with estrogen receptor antagonist ICI 182,780 (Sham + ICI), and ACF treated with ICI. Cardiac function was assessed temporally using echocardiogram, and tissue samples were collected at 5 days and 6 wk postsurgery. All rats with volume overload had significantly increased card...
Source: AJP: Heart and Circulatory Physiology - December 31, 2016 Category: Cardiology Authors: El Hajj, M. C., Ninh, V. K., El Hajj, E. C., Bradley, J. M., Gardner, J. D. Tags: RESEARCH ARTICLE Source Type: research

Acute limb heating improves macro- and microvascular dilator function in the leg of aged humans
Local heating of an extremity increases blood flow and vascular shear stress throughout the arterial tree. Local heating acutely improves macrovascular dilator function in the upper limbs of young healthy adults through a shear stress-dependent mechanism but has no such effect in the lower limbs of this age group. The effect of acute limb heating on dilator function within the atherosclerotic prone vasculature of the lower limbs of aged adults is unknown. Therefore, the purpose of this study was to test the hypothesis that acute lower limb heating improves macro- and microvascular dilator function within the leg vasculatur...
Source: AJP: Heart and Circulatory Physiology - December 31, 2016 Category: Cardiology Authors: Romero, S. A., Gagnon, D., Adams, A. N., Cramer, M. N., Kouda, K., Crandall, C. G. Tags: RESEARCH ARTICLE Source Type: research

Prediction of hemodynamics under left ventricular assist device
In conclusion, the circulatory equilibrium framework predicts quantitatively the hemodynamic impact of LVAD. This knowledge would contribute to safe management of patients with LV failure undergoing LVAD implantation. NEW & NOTEWORTHY Hemodynamic response to left ventricular assist device (LVAD) has not been quantitatively investigated. This is the first report of quantitative prediction of the hemodynamics on LVAD using circulatory equilibrium framework. The validated framework allows us to simulate the impact of LVAD on right atrial pressure under various right ventricular functions. (Source: AJP: Heart and Circulatory Physiology)
Source: AJP: Heart and Circulatory Physiology - December 31, 2016 Category: Cardiology Authors: Kakino, T., Saku, K., Sakamoto, T., Sakamoto, K., Akashi, T., Ikeda, M., Ide, T., Kishi, T., Tsutsui, H., Sunagawa, K. Tags: RESEARCH ARTICLE Source Type: research

Exaggerated coronary vasoconstriction limits muscle metaboreflex-induced increases in ventricular performance in hypertension
Increases in myocardial oxygen consumption during exercise mainly occur via increases in coronary blood flow (CBF) as cardiac oxygen extraction is high even at rest. However, sympathetic coronary constrictor tone can limit increases in CBF. Increased sympathetic nerve activity (SNA) during exercise likely occurs via the action of and interaction among activation of skeletal muscle afferents, central command, and resetting of the arterial baroreflex. As SNA is heightened even at rest in subjects with hypertension (HTN), we tested whether HTN causes exaggerated coronary vasoconstriction in canines during mild treadmill exerc...
Source: AJP: Heart and Circulatory Physiology - December 31, 2016 Category: Cardiology Authors: Spranger, M. D., Kaur, J., Sala-Mercado, J. A., Krishnan, A. C., Abu-Hamdah, R., Alvarez, A., Machado, T. M., Augustyniak, R. A., OLeary, D. S. Tags: RESEARCH ARTICLE Source Type: research

Myocardial interstitial levels of serotonin and its major metabolite 5-hydroxyindole acetic acid during ischemia-reperfusion
The aim of this study was to examine the accumulation of serotonin (5-HT) and degradation of 5-HT taken up into cells in the ischemic region during myocardial ischemia-reperfusion. Using microdialysis technique in anesthetized rats, we monitored myocardial interstitial levels of 5-HT and its metabolite produced by monoamine oxidase (MAO), 5-hydroxyindole acetic acid (5-HIAA), during 30-min coronary occlusion followed by 45-min reperfusion, and investigated the effects of local administration of the MAO inhibitor pargyline and the 5-HT uptake inhibitor fluoxetine. In the vehicle group, the dialysate 5-HT concentration incre...
Source: AJP: Heart and Circulatory Physiology - December 31, 2016 Category: Cardiology Authors: Du, C.-K., Zhan, D.-Y., Akiyama, T., Inagaki, T., Shishido, T., Shirai, M., Pearson, J. T. Tags: RESEARCH ARTICLE Source Type: research