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Effect of 6 wk of high-intensity one-legged cycling on functional sympatholysis and ATP signaling in patients with heart failure.
Munch, GW, Iepsen, UW, Ryrsø, CK, Rosenmeier, JB, Pedersen, BK, Mortensen, SP
American journal of physiology. Heart and circulatory physiology. 2018;(3):H616-H626
Abstract
Breathlessness during daily activities is the primary symptom in patients with heart failure (HF). Poor correlation between the hemodynamic parameters of left ventricular performance and perceived symptoms suggests that other factors, such as skeletal muscle function, play a role in determining exercise capacity. We investigated the effect of 6 wk of high-intensity, one-legged cycling (HIC; 8 × 4 at 90% one-legged cycling max) on 1) the ability to override sympathetic vasoconstriction (arterial infusion of tyramine) during one-legged knee-extensor exercise (KEE), 2) vascular function (arterial infusion of ACh, sodium nitroprusside, tyramine, and ATP), and 3) exercise capacity in HF patients with reduced ejection fraction ( n = 8) compared with healthy individuals ( n = 6). Arterial tyramine infusion lowered leg blood flow and leg vascular conductance at rest and during KEE before the training intervention in both groups ( P < 0.05) but not during KEE after the training intervention. There was no difference between groups. The peak vasodilatory response to ATP was blunted in HF patients ( P < 0.05), whereas there was no difference in ACh- and sodium nitroprusside-induced vasodilation between HF patients and healthy individuals. ACh-induced vasodilation increased in HF patients after the training intervention ( P < 0.05). HIC improved aerobic capacity in both groups ( P < 0.05), whereas only HF patients made improvements in the 6-min walking distance ( P < 0.05). These results suggest that exercise hyperemia and functional sympatholysis are not altered in HF patients and that functional sympatholysis is improved with HIC in both HF patients and healthy individuals. Moreover, these results suggest that the peak vasodilatory response to ATP is blunted in HF. NEW & NOTEWORTHY The ability to override sympathetic vasoconstrictor activity (by arterial tyramine infusion) during exercise is not different between heart failure patients and healthy individuals and is improved by high-intensity, one-legged cycling training. The peak vasodilatory response to ATP is reduced in heart failure patients.
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Pioglitazone, a peroxisome proliferator-activated receptor γ activator, suppresses coronary spasm.
Morita, S, Mizuno, Y, Harada, E, Kashiwagi, Y, Yoshimura, M, Murohara, T, Yasue, H
Coronary artery disease. 2014;(8):671-7
Abstract
OBJECTIVE We examined whether a peroxisome proliferator-activated receptor γ (PPAR-γ) agonist, pioglitazone, suppresses coronary spasm. BACKGROUND Patients with coronary spastic angina (CSA) also have endothelial dysfunction and inflammation. Activation of PPAR-γ improves endothelial dysfunction and inflammation. PARTICIPANTS AND METHODS The study participants included 73 consecutive CSA patients (47 men and 26 women, mean age 63.6±10.4 years) who were admitted to our institution with a suspicion of CSA because of episodes of chest discomfort occurring mostly at rest in whom coronary spasm was induced by an intracoronary acetylcholine injection and a repeat acetylcholine provocation injection was administered after 6 months of follow-up. Thirty-six of the patients were administered pioglitazone15-30 mg/day added on calcium channel blockers (CCBs) (pioglitazone group) and 37 were administered CCBs alone (control group). Clinical and laboratory data were also examined before and after 6 months of follow-up and the results between the two groups were compared. RESULTS Coronary spasm was suppressed in 18/36 patients (50.0%) in the pioglitazone group (P<0.001) and 8/37 patients (21.6%) in the control group (P=0.008) after 6 months of treatment. Coronary spasm was thus significantly reduced in the pioglitazone group compared with the control group (P=0.011). The levels of total white blood cell count and high-sensitivity C-reactive protein decreased significantly (P<0.001 and P<0.001, respectively) in the pioglitazone group, whereas these levels did not differ in the control group (P=0.15 and 0.39, respectively) after the treatment. CONCLUSION Pioglitazone added on CCBs significantly reduced coronary spasm compared with CCBs alone after 6 months of treatment. Pioglitazone may thus prove to be a novel therapy for coronary spasm.
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Endothelial dysfunction, ADMA and insulin resistance in essential hypertension.
Perticone, F, Sciacqua, A, Maio, R, Perticone, M, Galiano Leone, G, Bruni, R, Di Cello, S, Pascale, A, Talarico, G, Greco, L, et al
International journal of cardiology. 2010;(3):236-41
Abstract
BACKGROUND Endothelial dysfunction and insulin resistance (IR) are associated with essential hypertension and other cardiovascular risk factors. Asymmetric dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide synthase, induces endothelial dysfunction in different setting of patients. However, at this moment no data are available about the role of ADMA and IR to induce endothelial dysfunction in an independent way or combined between them. In this study, we investigated, in 63 hypertensives and 21 normotensive healthy subjects, the relationship between ADMA and IR and their possible interaction on endothelial function. METHODS ADMA plasma levels were measured by high-performance liquid chromatography, and IR by homeostasis model assessment (HOMA). Endothelial function was estimated by intra-arterial infusion of acetylcholine (ACh) and sodium nitroprusside at increasing doses. RESULTS Hypertensive patients had significantly higher ADMA, insulin, HOMA and C-reactive protein (CRP) values than normotensive controls (P<0.0001). There were no significant differences in mean l-arginine/ADMA ratio between groups. ACh-stimulated forearm blood flow (FBF) was significantly reduced in hypertensive patients (P<0.0001). In hypertensive group, HOMA was the strongest determinant of FBF, accounting for the 45.5% of its variation. ADMA and gender were the independent determinants of HOMA, accounting for 12.3% and 8.3% of its variation, respectively. CONCLUSIONS The association between ADMA and IR contributes to identify a possible novel mechanism by which ADMA promotes vascular damage, increasing individual cardiovascular risk in hypertensive patients. However, this hypothesis should be tested in a larger study group.
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Upregulation of ecto-5'-nucleotidase by rosuvastatin increases the vasodilator response to ischemia.
Meijer, P, Wouters, CW, van den Broek, PH, de Rooij, M, Scheffer, GJ, Smits, P, Rongen, GA
Hypertension (Dallas, Tex. : 1979). 2010;(4):722-7
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Abstract
3-Hydroxy-3-methyl-glutaryl-coenzyme A reductase inhibitors (statins) are effective in the primary and secondary prevention of cardiovascular events. Although originally developed to improve lipid profile, statins have demonstrated a surplus of beneficial pleiotropic effects, including improved endothelial function, reduced inflammation, and increased tolerance to ischemia-reperfusion injury. In preclinical studies, increased ecto-5'-nucleotidase activity, the key enzyme in extracellular adenosine formation, plays an important role in these effects. Because human data are absent, we explored the effects of rosuvastatin on ecto-5'-nucleotidase activity and the clinical relevance of increased extracellular adenosine during ischemia in humans in vivo. The forearm vasodilator responses to 3 increasing periods of forearm ischemia (2, 5, and 13 minutes) were determined during placebo and caffeine (an adenosine receptor antagonist) infusion into the brachial artery. At the end of an 8-day treatment period with rosuvastatin (20 mg per day), this whole procedure was repeated. During both experiments, ecto-5'-nucleotidase activity was determined. Vasodilator responses are expressed as the percentage increase in forearm blood flow ratio from baseline. Rosuvastatin increased ecto-5'-nucleotidase activity by 49±17% and enhanced the vasodilator response after 2, 5, and 13 minutes of ischemia in the absence (146±19, 330±26, and 987±133 to 312±77, 566±107, and 1533±267) but not in the presence of caffeine (98±25, 264±54, and 727±111 versus 95±19, 205±34, and 530±62). Rosuvastatin increases extracellular formation of adenosine in humans in vivo probably by enhancing ecto-5'-nucleotidase activity. This action results in the improvement of reactive hyperemia and may further enhance the clinical benefit of statins, in particular in conditions of ischemia.
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Effect of different vasodilators on NTPDase activity in healthy and hypertensive patients.
Lunkes, DS, Lunkes, GI, Ahmed, M, Morsch, AL, Zanin, RF, Maldonado, PA, Corrêa, M, Schetinger, MR, Morsch, VM
Thrombosis research. 2009;(3):268-74
Abstract
INTRODUCTION The thrombogenic process that affects the hypertensive patient is associated with regulatory mechanisms present in the vascular endothelium. These mechanisms involve release of an endothelium-derived relaxing factor, ectonucleotidase activity and calcium ion concentration. METHODS Interference with ENTPDase activity in platelets of hypertensive patients and healthy donors was evaluated for arginine, sodium nitroprusside, and hydralazine. In addition, the kinetic behavior of NTPDase was determined in the presence of the vasodilator that showed the greatest inhibitory influence. RESULTS Vasodilators decreased NTPDase activity with ATP and ADP as substrates. In controls, hydrolysis was increased in the presence of arginine. Captopril did not affect enzyme activities. The dose response for increasing sodium nitroprusside was biphasic. Kinetic behavior studies were estimated in the presence of sodium nitroprusside, which caused a mixed inhibition. The K(m) values increased and V(max) decreased with increasing sodium nitroprusside concentrations. The IC(50) and K(i) values indicated that the vasodilator was a strong NTPDase inhibitor when tested for the control and hypertensive group, using ATP and ADP as substrate, respectively. CONCLUSION It is postulated that there was an interaction between vasodilators, NO donors and inhibition of NTPDase.
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Dipyridamole enhances ischaemia-induced reactive hyperaemia by increased adenosine receptor stimulation.
Meijer, P, Wouters, CW, van den Broek, PH, Scheffer, GJ, Riksen, NP, Smits, P, Rongen, GA
British journal of pharmacology. 2008;(6):1169-76
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BACKGROUND AND PURPOSE Dipyridamole enhances post-occlusive reactive hyperaemia (PORH) in the human forearm vascular bed. We hypothesize that this effect is completely mediated by increased adenosine receptor stimulation. To test this hypothesis, the effect of caffeine (an adenosine receptor antagonist) on dipyridamole-induced augmentation of PORH was explored. EXPERIMENTAL APPROACH The forearm vasodilator responses to three increasing periods of forearm ischaemia (2, 5 and 13 min) were determined during placebo infusion. Forty minutes after the last reperfusion period, this procedure was repeated during intra-arterial infusion of dipyridamole (7.4 nmol min(-1) per 100 ml forearm). At least 2 weeks later, this whole procedure was repeated, but now in the presence of caffeine (90 microg min(-1) per 100 ml volume). KEY RESULTS After 2, 5 and 13 min of ischaemia, the average forearm blood flow increased to 5.6+/-0.7, 9.7+/-1.3 and 34.5+/-2.1 ml min(-1) per 100 ml. After infusion of dipyridamole into the brachial artery, these numbers were significantly increased to 7.7+/-0.8, 12.5+/-1.5 and 41.6+/-3.1 ml min(-1) per 100 ml. This response was abolished by the concomitant infusion of caffeine (6.6+/-0.5, 10.2+/-0.6, 35.1+/-2.2 (caffeine) versus 7.4+/-0.4, 10.5+/-0.6, 33.7+/-2.2 ml min(-1)per 100 ml (caffeine/dipyridamole)). CONCLUSIONS AND IMPLICATIONS Caffeine prevented the augmenting effect of dipyridamole on PORH. This indicates that dipyridamole-induced augmentation of PORH is mediated via increased adenosine receptor stimulation as a result of elevated extracellular formation of adenosine during ischaemia.
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Effects of rosiglitazone alone and in combination with atorvastatin on nontraditional markers of cardiovascular disease in patients with type 2 diabetes mellitus.
Chu, CS, Lee, KT, Lee, MY, Su, HM, Voon, WC, Sheu, SH, Lai, WT
The American journal of cardiology. 2006;(5):646-50
Abstract
Combination therapy of rosiglitazone and atorvastatin has been shown to have beneficial effects on glycemic control and lipid profiles in patients with type 2 diabetes mellitus. This study investigated the effects of the combination of rosiglitazone and atorvastatin on vascular inflammation by studying their effects on levels of biomarkers in patients with type 2 diabetes mellitus. Thirty patients with type 2 diabetes mellitus and hyperlipidemia were enrolled to receive rosiglitazone monotherapy at 4 mg/day for 3 months and then atorvastatin at 10 mg/day was added for 3 more months as combined therapy. Inflammatory biomarkers, including high-sensitivity C-reactive protein (hs-CRP), matrix metalloproteinase-9 (MMP-9), soluble CD40 ligand (sCD40L), and adiponectin, and lipid profiles were measured at the time of initiation, after rosiglitazone monotherapy and after combination therapy with rosiglitazone and atorvastatin. With treatment of rosiglitazone at 4 mg/day monotherapy for 3 months, hs-CRP levels decreased significantly by 26% (p <0.05) and adiponectin levels increased significantly by 192% (p <0.05), but no significant changes in levels of MMP-9 and sCD40L were demonstrated. After combination therapy, hs-CRP levels further significantly decreased by another 23% (p <0.05) and adiponectin further increased by another 124%. In addition, serum levels of MMP-9, sCD40L, total cholesterol, and low-density lipoprotein cholesterol decreased significantly compared with baseline levels. In conclusion, combination therapy with rosiglitazone and atorvastatin not only significantly improved lipid profiles but also decreased levels of vascular biomarkers, such as hs-CRP, MMP-9, and sCD40L, and increased serum adiponectin levels in patients with type 2 diabetes mellitus.
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Correction of peritubular capillary flow reduction with vasodilators restores function in focal segmental glomerulosclerotic nephrosis.
Futrakul, N, Futrakul, P, Siriviriyakul, P
Clinical hemorheology and microcirculation. 2004;(3):197-205
Abstract
Due to the previously therapeutic failure in treating eleven focal segmental glomerulosis (FSGS) nephrotic patients (group I) with prednisolone, cyclophosphamide and antihypertensive agents (reserpine, hydralazine or prazosin) who all entered end-stage renal disease, we prospectively evaluate 18 FSGS nephrotic patients who have been treated with combined formula consisting of ACEI, AIIRA, CCB, antiplatelet+/-heparin; group II. All the patients were subject to renal function studies namely creatinine clearance, fractional excretion of magnesium (FE Mg) and intrarenal hemodynamics. Treatment outcome of patients in group II was comparatively assessed before and after therapy. Clinical profiles were comparatively matched between groups I and II. The intrarenal hemodynamic study in all nephrotic patients revealed hemodynamic maladjustment characterized by preferential constriction at the efferent arteriole. Such constriction induced intraglomerular hypertension and exaggeratedly reduced peritubular capillary flow (PTCF). Following treatment with combined formula (group II), reductions in efferent arteriolar resistance and intraglomerular hydrostatic pressure were observed in conjunction with the increases in PTCF and glomerular filtration rate in all 18 patients. Correction of hemodynamic maladjustment with combined formula effectively restores renal function and thereby prevents the renal disease progression in FSGS nephrosis.
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Effect of beraprost sodium on pulmonary vascular resistance in candidates for a Fontan procedure: a preliminary study.
Takahashi, K, Mori, Y, Yamamura, H, Nakanishi, T, Nakazawa, M
Pediatrics international : official journal of the Japan Pediatric Society. 2003;(6):671-5
Abstract
OBJECTIVE Although long-term prostacyclin(PGI2) therapy in patients with severe pulmonary hypertension (PH)reduces pulmonary vascular resistance (PVR), there have been no reports on its therapeutic effects in patients with mild PH. We investigated the chronic effect of beraprost sodium (BPS), an oral PGI2 analog, in children with mild PH. METHODS We studied 20 patients who were destined for a Fontan procedure with a mean pulmonary arterial pressure(PAP) of>20 mmHg and/or PVR of>3.0 Wood units. Both the PAP and the PVR in these cases were too high for patients to undergo a successful Fontan procedure. Seven patients received BPS (PG group) and 13 did not (control group). All patients underwent repeat cardiac catheterization to examine pulmonary hemodynamics. RESULTS In the PG group, the pulmonary-to-systemic flow ratio (Qp/Qs) did not change after BPS administration(1.1 +/- 0.6 vs 1.3 +/- 0.9);however, the mean PAP decreased significantly (25.3 +/- 8.2 vs 19.9 +/- 6.5 mmHg; P < 0.05),as did PVR (3.7 +/- 1.3 vs 2.3 +/- 0.9 Wood units; P < 0.05), whereas the pulmonary artery (PA) index increased significantly (312 +/- 136 vs 375 +/- 165; P < 0.05). In the control group, the mean PAP decreased significantly (24.9 +/- 4.7 vs 19.8 +/- 6.3 mmHg; P < 0.05)and the PA index increased significantly (295 +/- 72 vs 362 +/- 114; P < 0.05). No significant changes in Qp/Qs (1.5 +/- 0.8 vs 1.4 +/- 0.6)or PVR (2.9 +/- 1.3 vs 2.5 +/- 0.8 Wood units) were observed. CONCLUSION We conclude that long-term BPS administration probably reduces PVR in potential candidates for a Fontan procedure with mild PH. This treatment would reduce the risks associated with the Fontan procedure and would also improve its outcome.
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Topical methyl nicotinate-induced skin vasodilation in diabetic neuropathy.
Caselli, A, Hanane, T, Jane, B, Carter, S, Khaodhiar, L, Veves, A
Journal of diabetes and its complications. 2003;(4):205-10
Abstract
OBJECTIVE To evaluate the vasodilation induced by topical application of methyl nicotinate (MN) and to compare it with the vasodilatory response to acetylcholine (ACh) and sodium nitroprusside (SNP) in healthy subjects and diabetic neuropathic patients. RESEARCH DESIGN AND METHODS Ten diabetic patients with peripheral neuropathy (DN) and 10 age- and sex-matched healthy control subjects (C) were enrolled. The vasodilatory response to topical application of 1% MN and a placebo emulsion at the forearm and dorsum of the foot skin at 5, 15, 30, 60 and 120 min was measured using Laser Doppler Perfusion Imaging. The vasodilatory response to iontophoresis of 1% ACh and 1% SNP solutions was also evaluated. RESULTS The maximal vasodilatory response to ACh, SNP and MN was similar at the forearm and foot level in the diabetic patients. In the control group, the responses to MN, ACh and SNP were similar on the forearm but in the foot, the MN vasodilatory response was higher when compared to the ACh and SNP responses. MN-related vasodilation was present 5 min after the application, reached its peak at 15-30 min and declined to pre-application levels 120 min afterward. CONCLUSIONS Topical application of MN at the forearm and foot levels of diabetic neuropathic patients results in skin vasodilation that is comparable to the maximal vasodilation that can be induced by iontophoresis of ACh or SNP and lasts for less than 2 h. Further studies will be required to explore the potential of MN to increase blood flow and to prevent diabetic foot problems in clinical practice.