The Experts below are selected from a list of 8013 Experts worldwide ranked by ideXlab platform
Shin-ichi Momomura - One of the best experts on this subject based on the ideXlab platform.
-
Effects of submaximal exercise on Blood Rheology and sympathetic nerve activity.
Circulation, 2010Co-Authors: Nahoko Ikeda, Takanori Yasu, Ken Tsuboi, Yoshitaka Sugawara, Norifumi Kubo, Tomio Umemoto, Kenshiro Arao, Masanobu Kawakami, Shin-ichi MomomuraAbstract:Background: To explore the acute effects of submaximal exercise on Blood Rheology and sympathetic nerve activity. Methods and Results: The effects of exercise (20 or 80 Watts (W)) on Blood Rheology and sympathetic nerve activity were assessed in 10 healthy Japanese men. Blood sampling and heart rate variability (HRV) recording were performed during 20-min supine rest and standing ergometric exercise (20 W for 10 min, 80 W for 10 min) and recovery. Blood passage time across the microchannels (diameter, 7 μm) as a parameter of Blood Rheology, and the number of adhesive leukocytes on microchannel terraces as a parameter of leukocyte activation were measured. Sympathetic nerve activity was evaluated by plasma noradrenalin levels and the ratio of low-frequency (LF)/high-frequency (HF) by spectral analysis of HRV. Compared with values while supine at rest, significant increases in hematocrit, leukocyte count, noradrenalin level and Blood passage time were seen after strenuous ergometer exercise at 80 W (P
-
effects of submaximal exercise on Blood Rheology and sympathetic nerve activity
Circulation, 2010Co-Authors: Nahoko Ikeda, Takanori Yasu, Ken Tsuboi, Yoshitaka Sugawara, Norifumi Kubo, Tomio Umemoto, Kenshiro Arao, Masanobu Kawakami, Shin-ichi MomomuraAbstract:Background: To explore the acute effects of submaximal exercise on Blood Rheology and sympathetic nerve activity. Methods and Results: The effects of exercise (20 or 80 Watts (W)) on Blood Rheology and sympathetic nerve activity were assessed in 10 healthy Japanese men. Blood sampling and heart rate variability (HRV) recording were performed during 20-min supine rest and standing ergometric exercise (20 W for 10 min, 80 W for 10 min) and recovery. Blood passage time across the microchannels (diameter, 7 μm) as a parameter of Blood Rheology, and the number of adhesive leukocytes on microchannel terraces as a parameter of leukocyte activation were measured. Sympathetic nerve activity was evaluated by plasma noradrenalin levels and the ratio of low-frequency (LF)/high-frequency (HF) by spectral analysis of HRV. Compared with values while supine at rest, significant increases in hematocrit, leukocyte count, noradrenalin level and Blood passage time were seen after strenuous ergometer exercise at 80 W (P<0.01 each). The LF/HF ratio and nitric oxide metabolites tended to be increased with 80 W exercise. Conclusions: Strenuous exercise dynamically alters Blood rheological parameters, probably by changes in hematocrit and sympathetic nerve activity. (Circ J 2010; 74: 730-734)
Philippe Connes - One of the best experts on this subject based on the ideXlab platform.
-
altered Blood Rheology and impaired pressure induced cutaneous vasodilation in a mouse model of combined type 2 diabetes and sickle cell trait
Microvascular Research, 2019Co-Authors: Sarah Skinner, Philippe Connes, Dominique Sigaudoroussel, Ming Lo, Elie Nader, Audrey Jossetlamaugarny, Emmanuelle CharrinAbstract:Abstract Objective Type 2 diabetes (T2D)-related vascular dysfunction and hemorheological abnormalities could possibly be amplified by sickle cell trait (SCT). These alterations could potentially increase the risk of vascular complications in individuals with combined T2D and SCT. Therefore, this study used a mouse model to determine whether vascular function and Blood Rheology were more severely altered in combined T2D and SCT than in T2D or SCT alone. Methods Townes transgenic mice with or without SCT received a 12-week high fat high sucrose or standard diet to create models of combined T2D-SCT, T2D, SCT, and controls. Pressure-induced vasodilation (PIV) and sodium nitroprusside (SNP)-mediated vasodilation in-vivo, and hemorheological parameters were measured. Results No significant differences in Blood viscosity, hematocrit, erythrocyte deformability, or PIV were observed between the control and T2D mice, or the control and SCT mice. However, Blood viscosity, erythrocyte deformability, and PIV were significantly altered in the T2D-SCT mice compared to the control mice. There were no differences in SNP response between the groups. Conclusions Although neither T2D nor SCT alone had significant effects on Blood Rheology parameters or vascular function, combined T2D-SCT mice had significantly altered Blood Rheology and significantly impaired vascular function.
-
the role of Blood Rheology in sickle cell disease
Blood Reviews, 2016Co-Authors: Philippe Connes, Tamas Alexy, Jon A Detterich, Marc Romana, Marie Dominique Hardydessources, Samir K BallasAbstract:Studies performed in the last decades have highlighted the need to better understand the contribution of the endothelium, vascular function, oxidative stress, inflammation, coagulation, hemolysis and vascular adhesion mechanisms to the pathophysiology of acute vaso-occlusive like events and chronic organ damages in sickle cell disease (SCD). Although SCD is a hemorheological disease, a few works focused on the contribution of Blood viscosity, plasma viscosity, red Blood cell deformability and aggregation in the pathophysiology of SCD. After a brief description of basic hemoRheology, the present review focuses on the role of the hemorheological abnormalities in the causation of several SCD complications, mainly in sickle cell anemia and hemoglobin (Hb) SC disease. Several genetic and cellular modulators of Blood Rheology in SCD are discussed, as well as unresolved questions and perspectives.
-
Blood Rheology Blood flow and human health
Nutrition and Enhanced Sports Performance#R##N#Muscle Building Endurance and Strength, 2013Co-Authors: Philippe Connes, Stephane P Dufour, Aurelien Pichon, Fabrice FavretAbstract:Aerobic exercise capacity is tightly related to the ability of the cardiovascular system to bring enough oxygen to active muscles. This chapter first focuses on skeletal muscle Blood flow control and presents its responses to acute and chronic exercise, with a particular emphasis on the role of the active muscle mass and environmental factors. The second part describes how Blood Rheology impacts on the regulation of Blood flow and vascular function. The effects of acute and chronic exercise on Blood Rheology are then discussed, including Blood viscosity, red Blood cell deformability and aggregation. The last part focuses on a selection of nutritional supplements considered to have an impact on the cardiovascular system, Blood flow responses, Blood Rheology and ultimately exercise performance. We discuss how intermediates of the nitric oxide metabolism, antioxidants as well as minerals and trace elements could modulate Blood flow and Blood Rheology, and improve endurance exercise performance.
Takanori Yasu - One of the best experts on this subject based on the ideXlab platform.
-
Effects of submaximal exercise on Blood Rheology and sympathetic nerve activity.
Circulation, 2010Co-Authors: Nahoko Ikeda, Takanori Yasu, Ken Tsuboi, Yoshitaka Sugawara, Norifumi Kubo, Tomio Umemoto, Kenshiro Arao, Masanobu Kawakami, Shin-ichi MomomuraAbstract:Background: To explore the acute effects of submaximal exercise on Blood Rheology and sympathetic nerve activity. Methods and Results: The effects of exercise (20 or 80 Watts (W)) on Blood Rheology and sympathetic nerve activity were assessed in 10 healthy Japanese men. Blood sampling and heart rate variability (HRV) recording were performed during 20-min supine rest and standing ergometric exercise (20 W for 10 min, 80 W for 10 min) and recovery. Blood passage time across the microchannels (diameter, 7 μm) as a parameter of Blood Rheology, and the number of adhesive leukocytes on microchannel terraces as a parameter of leukocyte activation were measured. Sympathetic nerve activity was evaluated by plasma noradrenalin levels and the ratio of low-frequency (LF)/high-frequency (HF) by spectral analysis of HRV. Compared with values while supine at rest, significant increases in hematocrit, leukocyte count, noradrenalin level and Blood passage time were seen after strenuous ergometer exercise at 80 W (P
-
effects of submaximal exercise on Blood Rheology and sympathetic nerve activity
Circulation, 2010Co-Authors: Nahoko Ikeda, Takanori Yasu, Ken Tsuboi, Yoshitaka Sugawara, Norifumi Kubo, Tomio Umemoto, Kenshiro Arao, Masanobu Kawakami, Shin-ichi MomomuraAbstract:Background: To explore the acute effects of submaximal exercise on Blood Rheology and sympathetic nerve activity. Methods and Results: The effects of exercise (20 or 80 Watts (W)) on Blood Rheology and sympathetic nerve activity were assessed in 10 healthy Japanese men. Blood sampling and heart rate variability (HRV) recording were performed during 20-min supine rest and standing ergometric exercise (20 W for 10 min, 80 W for 10 min) and recovery. Blood passage time across the microchannels (diameter, 7 μm) as a parameter of Blood Rheology, and the number of adhesive leukocytes on microchannel terraces as a parameter of leukocyte activation were measured. Sympathetic nerve activity was evaluated by plasma noradrenalin levels and the ratio of low-frequency (LF)/high-frequency (HF) by spectral analysis of HRV. Compared with values while supine at rest, significant increases in hematocrit, leukocyte count, noradrenalin level and Blood passage time were seen after strenuous ergometer exercise at 80 W (P<0.01 each). The LF/HF ratio and nitric oxide metabolites tended to be increased with 80 W exercise. Conclusions: Strenuous exercise dynamically alters Blood rheological parameters, probably by changes in hematocrit and sympathetic nerve activity. (Circ J 2010; 74: 730-734)
J F Brun - One of the best experts on this subject based on the ideXlab platform.
-
hormones metabolism and body composition as major determinants of Blood Rheology potential pathophysiological meaning
Clinical Hemorheology and Microcirculation, 2002Co-Authors: J F BrunAbstract:The rheological properties of plasma and Blood cells are markedly influenced by the surrounding milieu: physicochemical factors, metabolism and hormones. Acid/base status, osmolality, lipid status and plasma protein pattern are well known to exert a major influence. The oxidative stress induced by increased free radicals production decreases red cell deformability. Among circulating substances, the divalent cations magnesium and zinc improve red cell deformability probably via calcium antagonistic effects. Some metabolites like lactate or ketone bodies decrease red cell deformability, although the former has apparently the opposite effect in highly trained individuals. Endothelium-derived factors such as nitric oxide (NO) and several arachidonic acid derivatives modulate both RBC and white cell mechanics. Endothelium regulates also Blood Rheology via the release of PAI- 1 which governs plasma fibrinogen levels. However, endothelium is not the only organ involved in the regulation of Blood Rheology: the kidney (by releasing erythropoietin which is a major viscoregulatory factor), the endocrine pancreas (via the action of insulin and glucagon on red cells), the adrenal gland (norepinephrine) and the endocrine heart (atrial natriuretic peptide) are also likely to exert important effects. Recently, increasing evidence is accumulating for a role of two other endocrine tissues in the regulation of Blood Rheology: the adipose tissue (free fatty acids, PAI-1, IL-6, leptin) and the pituitary gland (growth hormone-somatomedin axis, including the somatomedin carrier protein IGFBP1). These organs provide a link between body composition and hemoRheology, since GH and somatomedins are major regulators of the body content in fat and water while the endocrine activity of fat mass is apparently proportional to its size. These mechanisms explain to some extent why many situations, either physiological (diet, exercise) or pathological (diabetes, uremia) are associated with marked changes in Blood Rheology that may in turn modify micro and macrocirculatory hemodynamics and the distribution of O 2 and fuels to tissues.
-
the triphasic effects of exercise on Blood Rheology which relevance to physiology and pathophysiology
Clinical Hemorheology and Microcirculation, 1998Co-Authors: J F Brun, S Khaled, E Raynaud, D Bouix, J P Micallef, A OrsettiAbstract:: The life-extending effects of regular exercise are related to a decrease in both coronary and peripheral vascular morbidity, associated with some improvements in cardiovascular risk factors. A possible link between the beneficial metabolic and hemodynamic effects of exercise could be Blood Rheology, which is markedly affected by exercise. We propose here a description of the hemorheological effects of exercise as a triphasic phenomenon. Short-term effects of exercise are an increase in Blood viscosity resulting from both fluid shifts and alterations of erythrocyte rheologic properties (rigidity and aggregability). Increased Blood lactate, stress, and acute phase play a role in this process. Middle-term effects of regular exercise are a reversal of these acute effects with an increase in Blood fluidity, explained by plasma volume expansion (autohemodilution) that lowers both plasma viscosity and hematocrit. Long-term effects further improve Blood fluidity, parallel with the classical training-induced hormonal and metabolic alterations. While body composition, Blood lipid pattern, and fibrinogen improve (thus decreasing plasma viscosity), erythrocyte metabolic and rheologic properties are modified, with a reduction in aggregability and rigidity. On the whole, these improvements reflect a reversal of the so-called "insulin-resistance syndrome" induced by a sedentary lifestyle. Since impaired Blood Rheology has been demonstrated to be at risk for vascular diseases, the hemorheologic effects of exercise can be hypothesized to be a mechanism (or at least a marker) of risk reversal. This latter point requires further investigation. The physiological meaning of the triphasic pattern of exercise-induced alterations of Blood Rheology is uncompletely understood, but increased Blood fluidity may improve several steps of oxygen transfer to muscle, as clearly demonstrated in hypoxic conditions. Increasing evidence emerges from the literature, that Blood fluidity is a physiological determinant of fitness.
Nahoko Ikeda - One of the best experts on this subject based on the ideXlab platform.
-
Effects of submaximal exercise on Blood Rheology and sympathetic nerve activity.
Circulation, 2010Co-Authors: Nahoko Ikeda, Takanori Yasu, Ken Tsuboi, Yoshitaka Sugawara, Norifumi Kubo, Tomio Umemoto, Kenshiro Arao, Masanobu Kawakami, Shin-ichi MomomuraAbstract:Background: To explore the acute effects of submaximal exercise on Blood Rheology and sympathetic nerve activity. Methods and Results: The effects of exercise (20 or 80 Watts (W)) on Blood Rheology and sympathetic nerve activity were assessed in 10 healthy Japanese men. Blood sampling and heart rate variability (HRV) recording were performed during 20-min supine rest and standing ergometric exercise (20 W for 10 min, 80 W for 10 min) and recovery. Blood passage time across the microchannels (diameter, 7 μm) as a parameter of Blood Rheology, and the number of adhesive leukocytes on microchannel terraces as a parameter of leukocyte activation were measured. Sympathetic nerve activity was evaluated by plasma noradrenalin levels and the ratio of low-frequency (LF)/high-frequency (HF) by spectral analysis of HRV. Compared with values while supine at rest, significant increases in hematocrit, leukocyte count, noradrenalin level and Blood passage time were seen after strenuous ergometer exercise at 80 W (P
-
effects of submaximal exercise on Blood Rheology and sympathetic nerve activity
Circulation, 2010Co-Authors: Nahoko Ikeda, Takanori Yasu, Ken Tsuboi, Yoshitaka Sugawara, Norifumi Kubo, Tomio Umemoto, Kenshiro Arao, Masanobu Kawakami, Shin-ichi MomomuraAbstract:Background: To explore the acute effects of submaximal exercise on Blood Rheology and sympathetic nerve activity. Methods and Results: The effects of exercise (20 or 80 Watts (W)) on Blood Rheology and sympathetic nerve activity were assessed in 10 healthy Japanese men. Blood sampling and heart rate variability (HRV) recording were performed during 20-min supine rest and standing ergometric exercise (20 W for 10 min, 80 W for 10 min) and recovery. Blood passage time across the microchannels (diameter, 7 μm) as a parameter of Blood Rheology, and the number of adhesive leukocytes on microchannel terraces as a parameter of leukocyte activation were measured. Sympathetic nerve activity was evaluated by plasma noradrenalin levels and the ratio of low-frequency (LF)/high-frequency (HF) by spectral analysis of HRV. Compared with values while supine at rest, significant increases in hematocrit, leukocyte count, noradrenalin level and Blood passage time were seen after strenuous ergometer exercise at 80 W (P<0.01 each). The LF/HF ratio and nitric oxide metabolites tended to be increased with 80 W exercise. Conclusions: Strenuous exercise dynamically alters Blood rheological parameters, probably by changes in hematocrit and sympathetic nerve activity. (Circ J 2010; 74: 730-734)
