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.

Dynamin-related protein 1 mediates low glucose-induced endothelial dysfunction in human arterioles
Intensive glycemic regulation has resulted in an increased incidence of hypoglycemia. Hypoglycemic burden correlates with adverse cardiovascular complications and contributes acutely and chronically to endothelial dysfunction. Prior data indicate that mitochondrial dysfunction contributes to hypoglycemia-induced endothelial dysfunction, but the mechanisms behind this linkage remain unknown. We attempt to determine whether clinically relevant low-glucose (LG) exposures acutely induce endothelial dysfunction through activation of the mitochondrial fission process. Characterization of mitochondrial morphology was carried out ...
Source: AJP: Heart and Circulatory Physiology - February 28, 2017 Category: Cardiology Authors: Tanner, M. J., Wang, J., Ying, R., Suboc, T. B., Malik, M., Couillard, A., Branum, A., Puppala, V., Widlansky, M. E. Tags: RESEARCH ARTICLE Source Type: research

Caveolae-specific activation loop between CaMKII and L-type Ca2+ channel aggravates cardiac hypertrophy in {alpha}1-adrenergic stimulation
Activation of CaMKII induces a myriad of biological processes and plays dominant roles in cardiac hypertrophy. Caveolar microdomain contains many calcium/calmodulin-dependent kinase II (CaMKII) targets, including L-type Ca2+ channel (LTCC) complex, and serves as a signaling platform. The location of CaMKII activation is thought to be critical; however, the roles of CaMKII in caveolae are still elusive due to lack of methodology for the assessment of caveolae-specific activation. Our aim was to develop a novel tool for the specific analysis of CaMKII activation in caveolae and to determine the functional role of caveolar Ca...
Source: AJP: Heart and Circulatory Physiology - February 28, 2017 Category: Cardiology Authors: Tonegawa, K., Otsuka, W., Kumagai, S., Matsunami, S., Hayamizu, N., Tanaka, S., Moriwaki, K., Obana, M., Maeda, M., Asahi, M., Kiyonari, H., Fujio, Y., Nakayama, H. Tags: RESEARCH ARTICLE Source Type: research

Fluid shear stress induces upregulation of COX-2 and PGI2 release in endothelial cells via a pathway involving PECAM-1, PI3K, FAK, and p38
In this study we determined the major mechanotransduction pathway by which blood flow-driven shear stress activates cyclooxygenase-2 (COX-2) and prostaglandin I2 (PGI2) release in endothelial cells. Our work has demonstrated for the first time that COX-2/PGI2 mechanotransduction is mediated by the mechanosensor platelet endothelial cell adhesion molecule-1 (PECAM-1). (Source: AJP: Heart and Circulatory Physiology)
Source: AJP: Heart and Circulatory Physiology - February 28, 2017 Category: Cardiology Authors: Russell-Puleri, S., dela Paz, N. G., Adams, D., Chattopadhyay, M., Cancel, L., Ebong, E., Orr, A. W., Frangos, J. A., Tarbell, J. M. Tags: RESEARCH ARTICLE Source Type: research

lschemic preconditioning in pigs: a causal role for signal transducer and activator of transcription 3
Ischemic preconditioning (IPC), i.e., brief episodes of nonlethal myocardial ischemia-reperfusion (I/R) before sustained ischemia with subsequent reperfusion, reduces infarct size in all species tested so far, including humans. In rodents, the cardioprotective signal transduction causally involves an activation of Akt, ERK1/2, and STAT3. However, there are apparent species differences in the signal transduction between rodents and larger mammals such as pigs, where data on IPC's signal transduction are inconsistent for Akt and ERK1/2. The role of STAT3 has not yet been analyzed. Pigs were subjected to 60 min of left anteri...
Source: AJP: Heart and Circulatory Physiology - February 28, 2017 Category: Cardiology Authors: Gent, S., Skyschally, A., Kleinbongard, P., Heusch, G. Tags: RESEARCH ARTICLE Source Type: research

The role of sympathetic and vagal cardiac control on complexity of heart rate dynamics
Analysis of heart rate variability (HRV) by nonlinear approaches has been gaining interest due to their ability to extract additional information from heart rate (HR) dynamics that are not detectable by traditional approaches. Nevertheless, the physiological interpretation of nonlinear approaches remains unclear. Therefore, we propose long-term (60 min) protocols involving selective blockade of cardiac autonomic receptors to investigate the contribution of sympathetic and parasympathetic function upon nonlinear dynamics of HRV. Conscious male Wistar rats had their electrocardiogram (ECG) recorded under three distinct condi...
Source: AJP: Heart and Circulatory Physiology - February 28, 2017 Category: Cardiology Authors: Silva, L. E. V., Silva, C. A. A., Salgado, H. C., Fazan, R. Tags: RESEARCH ARTICLE Source Type: research

Differential effects of Mas receptor deficiency on cardiac function and blood pressure in obese male and female mice
Angiotensin-(1–7) [ANG-(1–7)] acts at Mas receptors (MasR) to oppose effects of angiotensin II (ANG II). Previous studies demonstrated that protection of female mice from obesity-induced hypertension was associated with increased systemic ANG-(1–7), whereas male obese hypertensive mice exhibited increased systemic ANG II. We hypothesized that MasR deficiency (MasR–/–) augments obesity-induced hypertension in males and abolishes protection of females. Male and female wild-type (MasR+/+) and MasR–/– mice were fed a low-fat (LF) or high-fat (HF) diet for 16 wk. MasR deficiency had no ...
Source: AJP: Heart and Circulatory Physiology - February 28, 2017 Category: Cardiology Authors: Wang, Y., Shoemaker, R., Powell, D., Su, W., Thatcher, S., Cassis, L. Tags: RESEARCH ARTICLE Source Type: research

Maternal-engineered nanomaterial exposure disrupts progeny cardiac function and bioenergetics
In conclusion, gestational nano-exposure significantly impairs the functional capabilities of the heart through cardiomyocyte impairment, which is associated with mitochondrial dysfunction. NEW & NOTEWORTHY Cardiac function is evaluated, for the first time, in progeny following maternal nanomaterial inhalation. The findings indicate that exposure to nano-sized titanium dioxide (nano-TiO2) during gestation negatively impacts cardiac function and mitochondrial respiration and bioenergetics. We conclude that maternal nano-TiO2 inhalation contributes to adverse cardiovascular health effects, lasting into adulthood. (Source...
Source: AJP: Heart and Circulatory Physiology - February 28, 2017 Category: Cardiology Authors: Hathaway, Q. A., Nichols, C. E., Shepherd, D. L., Stapleton, P. A., McLaughlin, S. L., Stricker, J. C., Rellick, S. L., Pinti, M. V., Abukabda, A. B., McBride, C. R., Yi, J., Stine, S. M., Nurkiewicz, T. R., Hollander, J. M. Tags: RESEARCH ARTICLE Source Type: research

High aminopeptidase A activity contributes to blood pressure control in ob/ob mice by AT2 receptor-dependent mechanism
In this study, we reported an increased angiotensin III generation in the circulation of ob/ob mice caused by a high aminopeptidase A activity. These findings are associated with an increased natriuresis found in these mice and support the role of renin-angiotensin-aldosterone system as additional mechanism regulating blood pressure in this genetic obese strain. (Source: AJP: Heart and Circulatory Physiology)
Source: AJP: Heart and Circulatory Physiology - February 28, 2017 Category: Cardiology Authors: Morais, R. L., Hilzendeger, A. M., Visniauskas, B., Todiras, M., Alenina, N., Mori, M. A., Araujo, R. C., Nakaie, C. R., Chagas, J. R., Carmona, A. K., Bader, M., Pesquero, J. B. Tags: RESEARCH ARTICLE Source Type: research

Association of serum HMGB2 level with MACE at 1 mo of myocardial infarction: Aggravation of myocardial ischemic injury in rats by HMGB2 via ROS
In conclusion, increased serum HMGB2 levels are associated with MI severity and MACE at 1 mo. HMGB2 promotes myocardial ischemic injury in rats and hypoxic H9C2 cell damage via ROS provoked by RAGE. NEW & NOTEWORTHY We demonstrate that serum high-mobility group box 2 is associated with major adverse cardiac events at 1 mo in myocardial infarction patients. Mechanistically, high-mobility group box 2 promotes reactive oxygen species production via receptor for advanced glycation end products signaling in ischemic myocardium, thereby aggravating cell apoptosis, inflammation, and autophagosome clearance impairment. This st...
Source: AJP: Heart and Circulatory Physiology - February 28, 2017 Category: Cardiology Authors: Liu, Z. H., Dai, D. P., Ding, F. H., Pan, W. Q., Fang, Y. H., Zhang, Q., Li, M., Yang, P., Wang, X. Q., Shen, Y., Wang, L. J., Yan, X. X., He, Y. H., Yang, K., Zhang, R. Y., Shen, W. F., Chen, Y., Lu, L. Tags: RESEARCH ARTICLE Source Type: research

The fate of sulfate in chronic heart failure
This study investigates sulfate clearance in chronic HF (CHF) patients and healthy individuals and considers its relationship with disease outcome. Parameters related to renal sulfate handling were determined in and compared between 96 previously characterized CHF patients and sex-matched healthy individuals. Among patients, sulfate clearance was analyzed for associations with clinical and outcome parameters. In CHF patients, plasma sulfate concentrations are significantly higher, whereas 24-h urinary excretion, fractional excretion, and clearance of sulfate are significantly lower, compared with healthy individuals. Among...
Source: AJP: Heart and Circulatory Physiology - February 28, 2017 Category: Cardiology Authors: Koning, A. M., Meijers, W. C., Minovic, I., Post, A., Feelisch, M., Pasch, A., Leuvenink, H. G. D., de Boer, R. A., Bakker, S. J. L., van Goor, H. Tags: RESEARCH ARTICLE Source Type: research

The interaction of estrogen and CSE/H2S pathway in the development of atherosclerosis
This study provides new insights into the interaction of H2S and estrogen signaling pathways on the regulation of cardiovascular functions. NEW & NOTEWORTHY Female cystathionine -lyase (CSE)-knockout mice have significantly lower plasma estrogen levels and more severe early atherosclerotic lesion than female wild-type mice. H2S production in liver and vascular tissues is enhanced by estrogen via its stimulatory effect on CSE activity. The antiatherosclerotic effect of estrogen is mediated by CSE-generated H2S. (Source: AJP: Heart and Circulatory Physiology)
Source: AJP: Heart and Circulatory Physiology - February 28, 2017 Category: Cardiology Authors: Li, H., Mani, S., Wu, L., Fu, M., Shuang, T., Xu, C., Wang, R. Tags: RESEARCH ARTICLE Source Type: research

Cardiac sympathetic innervation via middle cervical and stellate ganglia and antiarrhythmic mechanism of bilateral stellectomy
Cardiac sympathetic denervation (CSD) is reported to reduce the burden of ventricular tachyarrhythmias [ventricular tachycardia (VT)/ventricular fibrillation (VF)] in cardiomyopathy patients, but the mechanisms behind this benefit are unknown. In addition, the relative contribution to cardiac innervation of the middle cervical ganglion (MCG), which may contain cardiac neurons and is not removed during this procedure, is unclear. The purpose of this study was to compare sympathetic innervation of the heart via the MCG vs. stellate ganglia, assess effects of bilateral CSD on cardiac function and VT/VF, and determine changes ...
Source: AJP: Heart and Circulatory Physiology - February 28, 2017 Category: Cardiology Authors: Irie, T., Yamakawa, K., Hamon, D., Nakamura, K., Shivkumar, K., Vaseghi, M. Tags: RESEARCH ARTICLE Source Type: research

Reduced density and altered regulation of rat atrial L-type Ca2+ current in heart failure
In conclusion, reduction in PKA-dependent regulation did not contribute to downregulation of atrial ICaL in heart failure. NEW & NOTEWORTHY Whole cell recording of L-type Ca2+ currents in atrial myocytes from rat hearts subjected to coronary artery ligation compared with those from sham-operated controls reveals marked reduction in current density in heart failure without change in channel subunit expression and associated with altered phosphorylation independent of protein kinase A. (Source: AJP: Heart and Circulatory Physiology)
Source: AJP: Heart and Circulatory Physiology - February 28, 2017 Category: Cardiology Authors: Bond, R. C., Bryant, S. M., Watson, J. J., Hancox, J. C., Orchard, C. H., James, A. F. Tags: RESEARCH ARTICLE Source Type: research

Transgenic overexpression of macrophage matrix metalloproteinase-9 exacerbates age-related cardiac hypertrophy, vessel rarefaction, inflammation, and fibrosis
In conclusion, overexpression of MMP-9 in macrophages resulted in exacerbated cardiac hypertrophy in the setting of vessel rarefaction, which resulted in enhanced inflammation and fibrosis to augment the cardiac-aging phenotype. Our results provide evidence that macrophage-derived MMP-9 may be a therapeutic target in elderly subjects. NEW & NOTEWORTHY The present study was the first to use mice with transgenic overexpression of matrix metalloproteinase-9 (MMP-9) in macrophages to examine the effects of macrophage-derived MMP-9 on cardiac aging. We found that an elevation in macrophage-derived MMP-9 induced a greater ag...
Source: AJP: Heart and Circulatory Physiology - February 28, 2017 Category: Cardiology Authors: Toba, H., Cannon, P. L., Yabluchanskiy, A., Iyer, R. P., DArmiento, J., Lindsey, M. L. Tags: RESEARCH ARTICLE Source Type: research

Dendritic cells and isolevuglandins in immunity, inflammation, and hypertension
Hypertension is the major risk factor for morbidity and mortality from myocardial infarction, stroke, heart failure, and chronic kidney disease. Despite its importance, the pathogenesis of essential hypertension is poorly understood. During the past several years, it has become evident that T cells contribute to hypertension. Activated T cells accumulate in the perivascular space and the kidney and release cytokines that promote vascular dysfunction and end-organ damage. Although dendritic cells play a pivotal role in initiating adaptive immune responses, T cells have taken center stage in studies implicating the immune sy...
Source: AJP: Heart and Circulatory Physiology - February 28, 2017 Category: Cardiology Authors: Dixon, K. B., Davies, S. S., Kirabo, A. Tags: REVIEW Source Type: research