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Biomedical subjects

Axel Linke

Publications and source records attributed to Axel Linke.

At least 19 recordsLinked to original sources

Impact of renal dysfunction on immediate versus staged revascularization of non-culprit lesions in patients with ST segment elevation myocardial infarction: a pre-specified subgroup analysis of the randomized MULTISTARS AMI trial.

BACKGROUND: Renal dysfunction might affect outcomes in patients with ST-segment elevation myocardial infarction (STEMI) and multivessel coronary artery disease (MVD) undergoing percutaneous coronary intervention (PCI). METHODS: In MULTISTARS AMI, patients with STEMI and MVD were randomized to immediate or staged PCI of non-culprit lesions. In this pre-specified analysis, patients were stratified according to the presence of renal dysfunction at baseline, defined at an estimated glomerular filtration rate (eGFR) of 60&#xa0;ml/min/1.73 m2. Patients with an eGFR&#x2009;<&#x2009;30&#xa0;ml/min/1.73 m2 were excluded from the trial. The primary endpoint was a composite of death, non-fatal myocardial infarction, stroke, unplanned revascularization, or hospitalization for heart failure at 1&#xa0;year. RESULTS: In MULTISTARS AMI, 108 (13%) of 832 patients had renal dysfunction. The primary endpoint occurred more frequently in patients with renal dysfunction (19.4% vs. 11.2%, unadjusted HR 1.82, 95% CI 1.13-2.94), primarily driven by higher rates of death. Among patients with renal dysfunction, the rates of the primary end point were 14.5% and 24.5% in the immediate and staged PCI groups (unadjusted HR 0.55, 95% CI 0.23-1.33). There was no interaction between renal dysfunction and the randomized treatment assignment with respect to the primary end point (adjusted HR 1.30, 95% CI 0.8-2.20, pint 0.82). The occurrence of acute renal insufficiency was statistically similar in patients with renal dysfunction who underwent immediate and staged PCI (10.9% vs. 18.9%, unadjusted HR 0.61, 95% CI 0.22-1.72, pint 0.09). Renal dysfunction at baseline emerged as a strong risk factor for the development of acute renal insufficiency (adjusted HR 5.0, 95% CI 2.30-10.70, p&#x2009;<&#x2009;0.01). CONCLUSIONS: Outcomes with immediate compared to staged multivessel PCI did not appear significantly altered by the presence of renal dysfunction&#xa0;at baseline. (Supported by Boston Scientific; MULTISTARS AMI ClinicalTrials.gov number, NCT03135275).

Humans↗

Myocardial expression of Murf-1 and MAFbx after induction of chronic heart failure: Effect on myocardial contractility.

OBJECTIVE: In chronic heart failure (CHF) the myocardial expression of the inflammatory cytokine tumor necrosis factor alpha (TNF-alpha), which is thought to contribute to myocardial remodeling, was found to be increased. However, it is unknown whether the E3-ubiquitin ligases MAFbx and Murf-1 are involved in this remodeling process and whether their expression is regulated by TNF-alpha. METHODS: Rats underwent ligation of the left coronary artery to induce CHF or were sham-operated. The expression of MAFbx/Murf-1 and troponin I was analyzed by RT-PCR and Western blotting in the non-infarcted area of the left ventricle. In cell culture experiments the potency of TNF-alpha to stimulate Murf-1/MAFbx expression, the intracellular signaling pathway, and the involvement of the E3-ligases for the impairment of contractility were assessed. RESULTS: In CHF the myocardial expression of TNF-alpha was elevated 3.1-fold as compared to control. This was associated with a 4.5-fold and 2.7-fold increase in MAFbx and Murf-1 expression, respectively. A positive correlation between TNF-alpha and the expression of MAFbx or Murf-1 was evident. In neonatal rat cardiomyocytes, TNF-alpha induced the expression of MAFbx through p38MAPK-dependent pathways, whereas the induction of Murf-1 required the activation of the p42/44 MAPK pathway. Exposure of cardiomyocytes to TNF-alpha resulted in troponin I ubiquitinylation, subsequent degradation, and a decline in contractility. This was completely abrogated by siRNAs against Murf-1/MAFbx. CONCLUSION: TNF-alpha, which is increasingly expressed in CHF, induces troponin I degradation through a MAFbx/Murf-1-dependent pathway. This was associated with an impairment of contractility and might be one mechanism involved in the adverse remodeling process in CHF.

Animals↗

Adeno-associated virus-mediated transduction of VEGF165 improves cardiac tissue viability and functional recovery after permanent coronary occlusion in conscious dogs.

We have previously shown that VEGF165 gene delivery into ischemic skeletal muscle exerts not only proangiogenic, but also remarkable antiapoptotic and proregenerative activity. The aim of this study was to determine whether recombinant adeno-associated virus (rAAV)-mediated gene delivery of VEGF165 into cardiac muscle, during acute myocardial infarction, exerts a protective effect to promote long-term functional recovery. Acute infarction of the anterior LV wall was induced in 12 chronically instrumented dogs by permanent occlusion of the LAD coronary artery. Four hours after occlusion, rAAV-VEGF165 or rAAV-LacZ (n=6 each; 5x10(12) viral particles per animal) was directly injected with an echo-guided needle into the dysfunctional cardiac wall. LV and arterial pressure, dP/dtmax, and ejection fraction were not significantly different between the two groups over time. In contrast, in the infarcted region, at four weeks after infarction, fractional shortening was 75+/-18% and -3+/-15% of baseline and length-pressure area was 54+/-15% and 0.8+/-15% of baseline in VEGF165 versus LacZ, respectively (P<0.05). Histological analysis of the border regions showed a marked increase in the number of alpha-SMA-positive arterioles (68+/-2.8 versus 100+/-3.8 vessels per microscopic field in LacZ and VEGF165 group, respectively; P<0.05). In both groups, the receptor VEGFR-2 was diffusely expressed on the surviving cardiomyocytes and, consistently, myocardial viability was significantly improved in the VEGF165-treated group, with several troponin T-expressing cardiomyocytes displaying nuclear positivity for the proliferation marker PCNA. Altogether, our results indicate that VEGF165 gene delivery exerts a marked beneficial action by enhancing both arteriologenesis and cardiomyocyte viability in infarcted myocardium.

Adenoviridae↗

[Exercise training in the treatment of coronary artery disease and obesity].

Endothelial dysfunction has been identified as a major predictor of future cardiovascular events and precedes the development of coronary artery disease (CAD). Regular physical exercise training--as part of a multifactorial intervention--corrects endothelial dysfunction, improves symptoms in patients with CAD, augments myocardial perfusion, and reduces mortality of these patients. This review discusses potential mechanisms, which might be responsible for the exercise training-mediated reduction of mortality in secondary prevention. The activation of stem cells, which are known to regenerate damaged endothelium and promote the development of new vessels by vasculogenesis, the regression of atherosclerosis, the formation of collaterals, and the partial correction of endothelial dysfunction as a consequence of molecular adaptations will be evaluated in this context. However, the positive effects of exercise training in primary and secondary prevention of cardiovascular diseases are not restricted to the correction of endothelial dysfunction. Regular physical activity, either alone or as part of a multifactorial intervention consisting of diet and exercise training, is known to promote effective weight loss. Especially in patients with metabolic syndrome, weight reduction beneficially effects blood glucose control. It increases the levels of vasculoprotective high-density lipoprotein and augments the physical exercise capacity of these individuals. Additionally, regular physical activity attenuates the diet-induced loss in fat-free body mass by 50%, improves body composition and counteracts the reduction in basal energy expenditure, which is another big advantage compared to diet alone in the treatment of obesity. Moreover, physical exercise training is essential to maintain a body weight that has been achieved by caloric restriction. It is important to look for exercise interventions that can easily be integrated in daily life and are not associated with an increased risk of trauma, even in severely obese individuals. Most importantly, patients should enjoy the proposed kind of physical exercise.

Clinical Trials as Topic↗

Effects of exercise training on mortality in patients with coronary heart disease.

Endothelial dysfunction not only precedes the development of significant coronary artery stenosis, it has also been identified as a general phenomenon predicting future cardiovascular events in patients who are at risk. As regular physical activity as a part of a multifactorial intervention has been shown to affect symptoms beneficially, increase myocardial perfusion and--most importantly--reduce mortality in patients with coronary heart disease or myocardial infarction, this review will elucidate potential mechanisms responsible for the improvement in survival as a result of regular physical activity. The importance of exercise training-mediated regression of coronary stenosis, collateral formation, correction of endothelial dysfunction including the adaptation at the molecular level, as well as vasculogenesis will be discussed as possible underlying key players, and their potential contribution to the training-induced survival benefit in patients with coronary heart disease will be critically evaluated.

Coronary Circulation↗

Both T-786C and G894T polymorphism of endothelial nitric oxide synthase affect in-vitro endothelium-dependent relaxation of internal mammary artery rings from patients with coronary artery disease.

OBJECTIVES: Polymorphisms of endothelial nitric oxide synthase (eNOS) gene in the promoter (T-786C) and exon 7 (G894T) have been suggested to attenuate endothelial function. As it is unknown whether these polymorphisms, on top of classical risk factors, further deteriorate endothelium-dependent vasomotion, we aimed to elucidate the impact of both polymorphisms on the ex-vivo vasomotor function of left internal mammary artery rings from patients with coronary artery disease (CAD) undergoing coronary bypass surgery (CABG). METHODS: Mammary artery rings from 51 consecutive patients with CAD were obtained during elective CABG. Endothelium-dependent ring relaxation was measured in vitro in an organ chamber using acetylcholine (10 to 3 x 10 mol/l). Polymorphisms were determined by polymerase chain reaction restriction length polymorphism. RESULTS: Thirty-three per cent of patients were positive for the T-786C polymorphism, 25% for the G894T polymorphism, and 18% carried mutated alleles in both loci. Maximal acetylcholine-induced ring relaxation was 46.7+/-3.2% in T-786C, 59.6+/-4.2% in G894T, and 66.7+/-7.4% in T-786C/G894T compared with 94.9+/-2.0% in wild-type subjects (P<0.05 versus T-786C, G894T, T-786C/G894T). Patients positive for an eNOS polymorphism with more than three cardiovascular risk factors displayed a further attenuation of acetylcholine-mediated relaxation (45+/-6 %) compared with having up to three risk factors (59+/-3%, P<0.05). CONCLUSION: In patients with CAD, in-vitro assessed endothelium-dependent relaxation of mammary arteries was significantly impaired in those positive for the T-786C or the G894T eNOS polymorphism. These results suggest that the presence of either one of the eNOS polymorphisms deteriorated endothelium-dependent vasodilatory capacity of large conduit vessels on top of classical risk factors in patients with CAD.

Aged↗

Transplantation of blood-derived progenitor cells after recanalization of chronic coronary artery occlusion: first randomized and placebo-controlled study.

Transplantation of blood-derived circulating progenitor cells (CPC) has been shown to improve myocardial regeneration after myocardial infarction. It remains unclear whether CPC transplantation exerts beneficial effects also in patients with chronic myocardial ischemia. We initiated a randomized, double-blind, placebo-controlled study evaluating the impact of intracoronary infusion of CPCs on coronary vasomotion and left ventricular (LV) function in patients after recanalization of chronic coronary total occlusion (CTO). After recanalization of CTO, 26 patients (age, 63+/-2 years; LV ejection fraction, 53+/-2%) were randomly assigned to the treatment (intracoronary transplantation of CPCs) or control group. Coronary flow reserve in response to adenosine (2.4 mg/min) was measured in the target vessel at the beginning of the study and after 3 months. LV function and infarct size were assessed by MRI and metabolism by 18F deoxyglucose positron emission tomography. CPC application resulted in an increase in coronary flow reserve by 43% from 2.3+/-0.3 to 3.3+/-0.5 (P<0.05 versus beginning and control). At 3 months, the number of hibernating segments in the target region (from 2.9+/-0.6 to 2.0+/-0.6 segments, P<0.05 versus beginning and control) had declined in the treatment group, whereas no significant changes were observed in the control group. MRI revealed a reduction in infarct size by 16% and an increase in LV ejection fraction by 14% in the treatment group (from 51.7+/-3.7 to 58.9+/-3.2%; P<0.05 versus beginning and control) because of an augmented wall motion in the target region. Hence, intracoronary transplantation of CPCs after recanalization of CTO results in an improvement of macro- and microvascular function and contributes to the recruitment of hibernating myocardium.

Angioplasty, Balloon, Coronary↗

Effects of exercise and ischemia on mobilization and functional activation of blood-derived progenitor cells in patients with ischemic syndromes: results of 3 randomized studies.

BACKGROUND: Exercise training (ET) has been shown to improve regional perfusion in ischemic syndromes. This might be partially related to a regeneration of diseased endothelium by circulating progenitor cells (CPCs) or CPC-derived vasculogenesis. The aim of the present study was to determine whether ischemic stimuli during ET are required to promote CPC mobilization in patients with cardiovascular diseases. METHODS AND RESULTS: Patients with peripheral arterial occlusive disease (PAOD) were randomized to 4 weeks of daily ischemic ET or control (group A). Successfully revascularized patients with PAOD were randomized to 4 weeks of daily nonischemic ET or control (group B). Patients with stable coronary artery disease were subjected to 4 weeks of subischemic ET or control (group C). At baseline and after 4 weeks, the number of KDR+/CD34+ CPCs was determined by fluorescence-activated cell sorting analysis. Levels of vascular endothelial growth factor (VEGF) were measured by ELISA. A Matrigel assay was used to quantify CPC integration into vascular structures. Expression of the homing factor CXCR4 was determined by reverse transcription-polymerase chain reaction. In group A only, ischemic ET increased VEGF levels by 310% (P<0.05 versus control) associated with an increase in CPCs by 440% (P<0.05 versus control), increased CXCR4 expression, and enhanced integration of CPCs into endothelial networks. In contrast, subischemic ET in groups B and C increased CXCR4 expression and CPC integration. CONCLUSIONS: In training programs, symptomatic tissue ischemia seems to be a prerequisite for CPC mobilization. However, ischemic and subischemic ET programs affect CXCR4 expression of CPCs, which might lead to an improved CPC integration into endothelial networks.

Aged↗

Stem cells in the dog heart are self-renewing, clonogenic, and multipotent and regenerate infarcted myocardium, improving cardiac function.

The purpose of this study was to determine whether the heart in large mammals contains cardiac progenitor cells that regulate organ homeostasis and regenerate dead myocardium after infarction. We report that the dog heart possesses a cardiac stem cell pool characterized by undifferentiated cells that are self-renewing, clonogenic, and multipotent. These clonogenic cells and early committed progeny possess a hepatocyte growth factor (HGF)-c-Met and an insulin-like growth factor 1 (IGF-1)-IGF-1 receptor system that can be activated to induce their migration, proliferation, and survival. Therefore, myocardial infarction was induced in chronically instrumented dogs implanted with sonomicrometric crystals in the region of the left ventricular wall supplied by the occluded left anterior descending coronary artery. After infarction, HGF and IGF-1 were injected intramyocardially to stimulate resident cardiac progenitor cells. This intervention led to the formation of myocytes and coronary vessels within the infarct. Newly generated myocytes expressed nuclear and cytoplasmic proteins specific of cardiomyocytes: MEF2C was detected in the nucleus, whereas alpha-sarcomeric actin, cardiac myosin heavy chain, troponin I, and alpha-actinin were identified in the cytoplasm. Connexin 43 and N-cadherin were also present. Myocardial reconstitution resulted in a marked recovery of contractile performance of the infarcted heart. In conclusion, the activation of resident primitive cells in the damaged dog heart can promote a significant restoration of dead tissue, which is paralleled by a progressive improvement in cardiac function. These results suggest that strategies capable of activating the growth reserve of the myocardium may be important in cardiac repair after ischemic injury.

Animals↗

Antioxidative effects of exercise training in patients with chronic heart failure: increase in radical scavenger enzyme activity in skeletal muscle.

BACKGROUND: In chronic heart failure (CHF), cross-talk between inflammatory activation and oxidative stress has been anticipated in skeletal muscle (SM). The role of the radical scavenger enzymes superoxide dismutase (SOD), catalase (Cat), and glutathione peroxidase (GPX), which remove oxygen radicals, has never been assessed in the SM in this context. Moreover, it remains unknown whether exercise training augments the activity of these enzymes in CHF. METHODS AND RESULTS: Twenty-three patients with CHF were randomized to either 6 months of exercise training (T) or a sedentary lifestyle (C); 12 age-matched healthy subjects (HS) were studied in parallel. Activity of Cat, SOD, and GPX was assessed in SM biopsies before and after 6 months (6 months). Oxidative stress was determined by measuring nitrotyrosine formation. SOD, Cat, and GPX activity was reduced by 31%, 57%, and 51%, respectively, whereas nitrotyrosine formation was increased by 107% in SM in CHF (P<0.05 versus HS). In CHF, exercise training augmented GPX and Cat activity in SM by 41% (P<0.05 versus before and group C) and 42% (P<0.05 versus before and group C), respectively, and decreased nitrotyrosine production by 35% (from 3.8+/-0.4% tissue area before to 2.5+/-0.3% after 6 months; P<0.05 versus before). CONCLUSIONS: The reduced activity of major antioxidative enzymes in the SM of CHF patients is associated with increased local oxidative stress. Exercise training exerts antioxidative effects in the SM in CHF, in particular, due to an augmentation in activity of radical scavenger enzymes.

Case-Control Studies↗

Carnitine palmitoyl transferase-I inhibition prevents ventricular remodeling and delays decompensation in pacing-induced heart failure.

OBJECTIVE: Experimental evidence suggests that modulation of myocardial substrate metabolism can markedly affect the progression of chronic heart failure (HF). We tested whether the inhibition of carnitine palmitoyl transferase-I (CPT-I), the enzyme regulating mitochondrial fatty acid oxidation, slows left ventricular remodeling and deterioration of function in pacing-induced HF. METHODS: Normal dogs (n=9) were compared to untreated dogs with pacing-induced HF (n=9) and HF dogs treated with 65 mg/kg/day of oxfenicine (HF+Oxf, n=9), a CPT-I inhibitor. RESULTS: HF+Oxf reached terminal failure (LV end-diastolic pressure=25 mm Hg) 6 days later than untreated HF (P<0.05). At 28 days of pacing, hemodynamic alterations and LV dilation were significantly attenuated and the 25% decrease in LV wall thickness was completely prevented in HF+Oxf vs. untreated HF, as was the activation of matrix metalloproteinase-2 and -9, markers of tissue remodeling. Oxfenicine also prevented HF-induced transcriptional down-regulation of CPT-I, medium chain acyl-CoA dehydrogenase, GAPDH and citrate synthase, key enzymes of cardiac energy metabolism. In addition, mRNA, but not protein levels of the nuclear receptor peroxisome proliferator-activated receptor-alpha were reduced in untreated HF, while they did not change significantly in HF+Oxf, as compared to control. CONCLUSIONS: CPT-I inhibition early in the development of HF prevented LV wall thinning and delayed the time to end-stage failure. While these results are limited to an experimental model of disease, they nevertheless suggest that CPT-I inhibition might be effective for slowing the progression of clinical HF.

Animals↗

Impact of regular physical activity on the NAD(P)H oxidase and angiotensin receptor system in patients with coronary artery disease.

BACKGROUND: In patients with stable coronary artery disease, physical exercise training (ET) improves endothelial dysfunction. A potential mechanism mediating the enhanced vasomotor function is a reduced breakdown of endothelium-derived nitric oxide by reactive oxygen species (ROS). The aim of the present study was to analyze the impact of ET on sources of ROS generation in the left internal mammary artery of patients with symptomatic coronary artery disease. METHODS AND RESULTS: In left internal mammary artery rings sampled during bypass surgery from 45 patients randomized to either a training (n=22) or an inactive control (n=23) group, the mRNA expression of NAD(P)H oxidase subunits, NAD(P)H oxidase activity, and ROS production were assessed. In addition, endothelial function, expression of angiotensin II (Ang II) receptor type 1 and 2 (AT1-R and AT2-R), and Ang II-mediated vasoconstriction were determined. ET resulted in a significant lower expression of gp91phox (23.1+/-0.5 versus 69.1+/-18.1 arbitrary units, training versus control), p22phox (0.7+/-0.3 versus 2.0+/-0.5 arbitrary units), and Nox4 (2.7+/-1.2 versus 5.4+/-1.0 arbitrary units). Enzymatic activity (2.1+/-0.3 versus 4.9+/-0.4 mU/mg) and ROS generation (0.02+/-0.01 versus 0.06+/-0.02 arbitrary units) were significantly lower in the training compared with the control group. On a functional level, ET resulted in improved acetylcholine-mediated vasodilatation and a 49% reduction in Ang II-induced vasoconstriction, accompanied by lower AT1-R (3.7+/-0.8 versus 16.6+/-5.7 arbitrary units, training versus control) and higher AT2-R (7.8+/-2.5 versus 1.6+/-0.7 arbitrary units) mRNA expression. CONCLUSIONS: ET reduces vascular expression of NAD(P)H oxidase and AT1-R, resulting in decreased local ROS generation. These molecular effects converge in a reduced Ang II-mediated vasoconstriction.

Aged↗

Hyperglycemia reduces survival and impairs function of circulating blood-derived progenitor cells.

OBJECTIVE: Function and availability of circulating progenitor cells (CPC) have been shown to be impaired in patients with diabetes mellitus (DM). Therefore, the aim of the present study was to analyze possible mechanisms leading to the reduction of CPC amount and function. METHODS AND RESULTS: Peripheral blood mononuclear cells (MNCs) of healthy donors (n=15) were cultivated under hyperglycemia (HG) conditions (12 mmol/L D-Glucose) or in osmotic control medium (Con) (5 mmol/L D-Glucose plus 7 mmol/L L-Glucose) for 7 days. CPC amount was determined by uptake of acetylated low-density lipoprotein and lectin binding. On the functional level, cell cycle status, nitric oxide (NO) production, and migrational and integrative capacity of CPCs were assessed. HG conditions caused a significant decrease in CPC amount derived from healthy MNCs. Furthermore, HG conditions led to a functional impairment, reflected in a decreased NO production and matrix metalloproteinase (MMP)-9 activity, as well as an impairment of the migrational and integrative capacities. CONCLUSIONS: HG, a main feature of DM, affects important functional characteristics of CPCs. These results may provide further insight into the pathomechanism of endothelial dysfunction in HG.

Adolescent↗

Effects of exercise training on insulin-like growth factor-I expression in the skeletal muscle of non-cachectic patients with chronic heart failure.

BACKGROUND: Chronic heart failure (CHF) is associated with progressive muscle atrophy and reduced local expression of insulin-like growth factor I (IGF-I). DESIGN: The present study was designed to test the hypothesis that the local deficiency of IGF-I in the skeletal muscle of patients with CHF would respond to a 6-months aerobic training intervention. Therefore, 18 patients [mean age 52.4 (SD 4.8) years, left ventricular ejection function (LVEF) 27 (SD 6)%] were prospectively randomized to either 6 months of training or sedentary lifestyle. METHODS: Serum levels of growth hormone (GH) were measured by immunofluorometric assay, IGF-I by competitive solid phase immunoassay. IGF-I expression was assessed in vastus lateralis biopsies by real-time PCR. RESULTS: Exercise training led to a significant increase in peak oxygen uptake by 26% [from 20.3 (SD 3.3) ml/kg per min to 25.5 (SD 5.7) ml/kg per min, P=0.003 versus control]. Local expression of IGF-I increased significantly after exercise training by 81% [from 6.3 (SE 0.8) to 11.4 (SE 1.4) relative units, P=0.007 versus control] while IGF-I receptor expression was reduced by 33% [from 20.0 (SE 2.1) to 13.8 (SE 1.7) relative units, P=0.008 versus control]. Serum growth hormone (GH) rose modestly from 0.12 (SE 0.07) to 0.65 (SE 0.37) ng/ml in the training group (P=0.043 versus baseline), however, this change was not significant compared to the control group (P=0.848). IGF-I serum levels remained virtually unchanged. CONCLUSIONS: Exercise training improves local IGF-I expression without significant changes of systemic parameters of the GH/IGF-I axis. These findings indicate that exercise training has the therapeutic potential to attenuate peripheral skeletal muscle alterations in particular with respect to local IGF-I expression in patients with moderate CHF.

Adult↗

Exercise training in chronic heart failure: correlation between reduced local inflammation and improved oxidative capacity in the skeletal muscle.

BACKGROUND: Chronic heart failure (CHF) is accompanied by an inflammatory activation which occurs both systemically and in the skeletal muscle. Exercise training has been shown to reduce the local expression of cytokines and inducible nitric oxide synthase (iNOS) in muscle biopsies of CHF patients. INOS-derived NO can inhibit oxidative phosphorylation and contribute to skeletal muscle dysfunction in CHF. DESIGN: To investigate the correlation between changes in local iNOS expression associated with regular exercise and changes in aerobic enzyme activities in the skeletal muscle of patients with CHF. Twenty male CHF patients [ejection fraction 25% (SE 2), age 54 (SE 2) years] were randomized to a training (n=10) or a control group (C, n=10). METHODS: At baseline and after 6 months skeletal muscle iNOS expression was measured by real-time polymerase chain reaction. INOS protein and protein nitrosylation were assessed by immunohistochemistry. Cytochrome c oxidase (COX) activity was quantified electrochemically using the Clark oxygen electrode. RESULTS: Exercise training led to a 27% increase in cytochrome c oxidase activity [from 21.8 (SE 3.2) to 27.7 (SE 3.5) nmol O2/mg per min, P=0.02 versus baseline]. Changes in iNOS expression and iNOS protein content were inversely correlated with changes in COX-activity (r=-0.60, P=0.01; r=-0.71, P<0.001). CONCLUSIONS: The inverse correlation between iNOS expression/iNOS protein content and COX-activity indicates that local anti-inflammatory effects may contribute to improved muscular oxidative metabolism.

Aged↗

Percutaneous coronary angioplasty compared with exercise training in patients with stable coronary artery disease: a randomized trial.

BACKGROUND: Regular exercise in patients with stable coronary artery disease has been shown to improve myocardial perfusion and to retard disease progression. We therefore conducted a randomized study to compare the effects of exercise training versus standard percutaneous coronary intervention (PCI) with stenting on clinical symptoms, angina-free exercise capacity, myocardial perfusion, cost-effectiveness, and frequency of a combined clinical end point (death of cardiac cause, stroke, CABG, angioplasty, acute myocardial infarction, and worsening angina with objective evidence resulting in hospitalization). METHODS AND RESULTS: A total of 101 male patients aged < or =70 years were recruited after routine coronary angiography and randomized to 12 months of exercise training (20 minutes of bicycle ergometry per day) or to PCI. Cost efficiency was calculated as the average expense (in US dollars) needed to improve the Canadian Cardiovascular Society class by 1 class. Exercise training was associated with a higher event-free survival (88% versus 70% in the PCI group, P=0.023) and increased maximal oxygen uptake (+16%, from 22.7+/-0.7 to 26.2+/-0.8 mL O2/kg, P<0.001 versus baseline, P<0.001 versus PCI group after 12 months). To gain 1 Canadian Cardiovascular Society class, 6956 dollars was spent in the PCI group versus 3429 dollars in the training group (P<0.001). CONCLUSIONS: Compared with PCI, a 12-month program of regular physical exercise in selected patients with stable coronary artery disease resulted in superior event-free survival and exercise capacity at lower costs, notably owing to reduced rehospitalizations and repeat revascularizations.

Aged↗