Integrated effects of the vasodilating beta-blocker nebivolol on exercise performance, energy metabolism, cardiovascular and neurohormonal parameters in physically active patients with arterial hypertension

Differential Metabolic Effects of Beta-Blockers: an Updated Systematic Review of Nebivolol

Blood pressure management in hypertensive patients with metabolic abnormalities is challenging, since many of the antihypertensive drugs adversely affect metabolism. Besides effective control of blood pressure in patients with hypertension, third-generation beta-blockers such as nebivolol offer additional benefits for central hemodynamics and neutral or beneficial effects on metabolism. Emerging clinical data suggest that nebivolol also has similar effects on metabolism in obese hypertensive and hypertensive diabetic patients. The present article will provide a systematic analysis of the pathophysiological links among hypertension, insulin resistance, and metabolic syndrome. We will also summarize the available clinical evidence regarding the metabolic effects of beta-blockers in hypertensive patients, with an emphasis on nebivolol. Nebivolol exerts neutral or beneficial effects on insulin sensitivity and lipid metabolism in hypertensive patients, owing to its nitric oxide-mediated vasodilatory and antioxidative properties. Thus, nebivolol could be a favorable therapeutic option for the treatment of hypertension in patients with impaired glucose and lipid metabolism.

Anxiety, Stress-Related Factors, and Blood Pressure in Young Adults

Hypertension (HT) is a long-term medical condition characterized by persistently elevated blood pressure (BP) in the arterial vessels. Although HT initially is an asymptomatic condition, it chronically evolves into a major risk factor for cardiovascular, cerebrovascular, and renal diseases that, in turn, represent crucial causes of morbidity and mortality in industrialized countries. HT is a complex disorder that is estimated to affect more than a quarter of the world's adult population. It is classified on the basis of both its pathophysiology (primary and secondary HT) and on the resting BP values (elevated systolic, diastolic, and pulse pressure). It originates from a complicated interaction of genes and several environmental risk factors including aging, smoking, lack of exercise, overweight and obesity, elevated salt intake, stress, depression, and anxiety. Anxiety and depressive disorders are the most commonly diagnosed mental disorders, affecting millions of people each year and impairing every aspect of everyday life, both of them characterized by affective, cognitive, psychomotor, and neurovegetative symptoms. Moreover, work-related stress has been considered as an important risk factor for HT and cardiovascular diseases (CVDs). Although different authors have investigated and suggested possible relations between HT, stress, anxiety, and depression during the last decades, a full understanding of the underlying pathophysiological mechanisms has not been satisfactorily achieved, especially in young adults. The aim of this study was to investigate the impact of anxiety and work-related stress in the development of HT amongst young health care profession students and the possible related consequences of early CVDs.

A single oral dose of flavan-3-ols enhances energy expenditure by sympathetic nerve stimulation in mice

Numerous clinical studies have found that ingestion of chocolate reduces the risk of metabolic syndrome, however, the mechanisms were remain unclear. We have reported that a single dose of a flavan-3-ol fraction derived from cocoa (FL) enhanced energy expenditure (EE) and increased the mRNA expression levels of uncoupling proteins (UCPs) and peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α), and the protein level of phosphorylated AMP-activated protein kinase (AMPK)α in tissues, along with plasma adrenaline level. In the present study, we examined whether the EE enhancing activity of FL is mediated by adrenergic effect using several adrenalin receptor (AR) blockers. In the first study, mice were butoxamine, as β2AR blocker, with vehicle or 10mg/kg FL orally. We found that pretreatment with butoxamine prevented the increases of EE, the mRNA expression of UCP-3, and phosphorylated AMPKα that were induced in the gastrocnemius muscle of mice by 10mg/kg FL. Secondly, mice were given SR52930, as β3AR blocker. Pretreatment with SR52930 prevented the increases of EE, the mRNA expression of UCP-3, and phosphorylated AMPKα that were induced in the gastrocnemius muscle of mice by 10mg/kg FL. Pretreatment with a combination of both blockers also reduced the increments in mRNA expression levels of UCPs and PGC-1α, however, phosphorylated AMPKα in skeletal muscle was rather increased. These results suggest that the ability of a single oral dose of FL to enhance metabolic activity is mediated by sympathetic nerve system (SNS).

[Antihypertensive drug therapy : Where do we stand?]

Antihypertensive drug therapy is one of the most successful medical measures ever, at all levels. The treatment situation in Germany has clearly improved in recent years. Nowadays, a wide range of very effective and well-tolerated hypertensive substances is available. Combination therapy has a long and successful tradition in hypertensive treatment, especially with suitable fixed combinations. Furthermore, the administration of fixed combinations is very beneficial to therapy adherence because it is essentially dependent on the number of drugs to be taken. The value of beta blockers and the double blockade of the renin-angiotensin-aldosterone system are under discussion and the interpretation of corresponding studies must be conducted very carefully. The hypertensive effect of a substance cannot be comprehensively assessed without taking the time of day, the time point of measurement and the time point of intake into consideration. This is particularly important with respect to the effect over 24 h. Optimal antihypertensive therapy must also take into consideration the individual blood pressure rhythm with respect to the dose and dosing intervals. The importance of the central (aortic) blood pressure as target blood pressure will increase.

A pharmacokinetic drug interaction study between nebivolol and paroxetine in healthy volunteers

WHAT IS KNOWN AND OBJECTIVE

Nebivolol is a highly selective beta-blocker with additional vasodilator properties, widely used in the clinical practice for the treatment of hypertension and heart failure. Paroxetine is a second-generation antidepressant and a potent inhibitor of CYP2D6, the same isoenzyme involved in the metabolism of nebivolol. The objective of this study was to investigate the effect of multiple-dose paroxetine intake on the pharmacokinetics of nebivolol in healthy volunteers and its potential consequences upon nebivolol pharmacodynamics.

METHODS

The study included 23 healthy subjects and was designed as an open-label, single-centre, non-randomized, two-period clinical trial. During period 1 (reference), each volunteer received a single dose of 5 mg nebivolol, whereas during period 2 (test), each volunteer received a single dose of 5 mg nebivolol and 20 mg paroxetine, after a pretreatment regimen with paroxetine (20-40 mg/day for 6 days). The pharmacokinetic parameters of nebivolol and its active metabolite were analysed by non-compartmental modelling. The pharmacodynamic parameters (blood pressure and heart rate) were assessed at rest, after each nebivolol intake.

RESULTS AND DISCUSSION

Pretreatment with paroxetine increased the mean peak plasma concentrations (Cmax ) for unchanged nebivolol (1·78 ± 1·17 vs. 4·24 ± 1·67 ng/mL) and for its active metabolite (0·58 ± 0·21 vs. 0·79 ± 0·24 ng/mL) compared to nebivolol alone. The time (tmax ) to reach Cmax was 1·37 ± 0·88 (h) and 3·11 ± 1·76 (h) for the parent compound and its active metabolite after nebivolol administered alone and 3·96 ± 1·76 (h), respectively, 7·33 ± 7·84 (h) after pretreatment with paroxetine. Also, the total areas under the curve (AUC0-∞ ) were significantly increased from 17·26 ± 43·06 to 106·20 ± 65·56 h ng/mL for nebivolol unchanged and 13·03 ± 11·29 to 74·56 ± 88·77 h ng/mL for its hydroxylated metabolite, before and after paroxetine intake. All the pharmacokinetic parameters presented statistically significant differences when paroxetine was administered with nebivolol. Nonetheless, statistical analysis did not show a significant difference between the vital signs measured during the two periods.

WHAT IS NEW AND CONCLUSION

After pretreatment with paroxetine, the exposure to nebivolol was increased by 6·1-fold for the parent drug and 5·7-fold for the hydroxylated active metabolite. Paroxetine influenced nebivolol pharmacokinetics in healthy volunteers, but it did not have a significant effect on nebivolol pharmacodynamic parameters measured at rest, although the clinical relevance of this drug interaction needs further investigation.

Platelet activation in essential hypertension during exercise: pre- and post-treatment changes with an angiotensin II receptor blocker

BACKGROUND

Acute exercise may exert deleterious effects on the cardiovascular system through a variety of pathophysiological mechanisms, including increased platelet activation. However, the degree of exercise-induced platelet activation in untreated hypertensive (UH) individuals as compared with normotensive (NT) individuals has yet to be established. Furthermore, the effect of antihypertensive treatment on exercise-induced platelet activation in essential hypertension (EH) remains unknown.

METHODS

Study 1 consisted of 30 UH and 15 NT subjects. UH subjects who received treatment were included in study 2 and were followed-up after a 3-month treatment period with an angiotensin II receptor blocker (ARB; valsartan). Circulating monocyte-platelet aggregates (MPA) and platelet P-selectin were measured as platelet activation markers at baseline, immediately after a treadmill exercise test, and 10, 30, and 90 minutes later.

RESULTS

Maximal platelet activation was observed at 10 minutes after peak exercise in both groups. In UH subjects, MPA levels remained increased at 30 minutes after peak exercise, despite BP fall to baseline levels. MPA levels were significantly higher in UH subjects than NT subjects at maximal exercise and at 10 and 30 minutes of recovery. Post-treatment MPA levels increased significantly only at 10 minutes into recovery and were similar to those of NT subjects.

CONCLUSIONS

Acute high-intensity exercise exaggerates platelet activation in untreated patients with EH compared with NT individuals. Angiotensin II receptor blockade with adequate BP control greatly improves exercise-induced platelet activation in EH. Further studies are needed to clarify whether this phenomenon depends purely on BP lowering or benefits also from the pleiotropic effects of ARBs.

Comparison of nebivolol and atenolol on blood pressure, blood sugar, and lipid profile in patients of essential hypertension

Background:

Nebivolol is a third-generation β-blocker, with highest β₁ selectivity and nitric-oxide-derived vasodilatation. It also exhibits antiproliferative and antioxidant property that has beneficial metabolic profile compared to second-generation β blockers like atenolol. This study was planned to study the comparative effects of nebivolol and atenolol on metabolic parameters in patients with essential hypertension.

Materials and Methods:

A prospective, randomized, parallel, open-label clinical study was carried out on patients with essential hypertension. The patients were randomly assigned to receive tablet atenolol (Group A) and nebivolol (Group B) for a period of 24 weeks. Investigations were carried out at baseline and at the end of study period, that is, 24 weeks. Out of 69 patients, 60 completed the study and the data was analyzed using student's t-test. P < 0.05 was considered statistically significant.

Results:

Atenolol and nebivolol both showed significant (P < 0.001) antihypertensive action after 24 weeks. Mean blood sugar and lipid profile were found to be significantly (P < 0.001) elevated after 24 weeks of treatment with atenolol but not with nebivolol. Heart rate was significantly (P < 0.001) decreased in both groups at 24 weeks.

Conclusion:

In view of metabolic adverse effects of atenolol, nebivolol is the better choice whenever β-blockers have to be used in essential hypertension.

[Physical training with beta-blockers in chronic heart failure]

In patients with chronic heart failure, the efficacy of beta-blocker therapy on mortality and the multiple benefits observed with physical training justify the association of the both. The effects of betablockade on different systems solicited in the exercise, particularly on the cardiocirculatory response during exercise test, rise many questions about the impact of beta blocker treatment on the changes induced by physical training. The cardioselective and vasodilating properties of beta-blockers play a role. It seems that the improved performance assessed by peak oxygen uptake (peak VO2) resulting from physical training is not limited by the beta-blocker treatment in patients with chronic heart failure. Synergistic effects have been observed, but many issues remain unsolved.

Efficacy and tolerability of nebivolol compared with other antihypertensive drugs: a meta-analysis

BACKGROUND AND OBJECTIVE

Lowering BP to normal levels without quality of life deterioration is the most important means of reducing cardiovascular risk. Recent studies have challenged the position of beta-adrenoceptor antagonists (beta-blockers) as first-line antihypertensive drugs. Nebivolol is a third-generation, highly selective beta(1)-blocker that causes vasodilation through nitric oxide (NO) release. This meta-analysis investigates the efficacy and tolerability of nebivolol compared with other antihypertensive drugs and placebo in patients with hypertension.

METHODS

Twelve randomized controlled studies were included in which nebivolol 5 mg once daily was compared with the recommended clinical doses of other antihypertensive drugs (n = 9), placebo (n = 2), and both (n = 1). The clinical studies were selected after a MEDLINE search up to 2007 using the key words 'nebivolol' and 'hypertension.'

RESULTS

Antihypertensive response rates (the percentage of patients achieving target BP levels or a defined DBP reduction) were higher with nebivolol than with ACE inhibitors (odds ratio [OR] 1.92; p = 0.001) and all antihypertensive drugs combined (OR 1.41; p = 0.001) and similar to beta-blockers, calcium channel antagonists (CCAs) and the angiotensin receptor antagonist (ARA) losartan. Moreover, a higher percentage of patients receiving nebivolol achieved target BP levels compared with patients treated with losartan (OR 1.98; p = 0.004), CCAs (OR 1.44; p = 0.024), and all antihypertensive drugs combined (OR 1.35; p = 0.012). The percentage of patients experiencing adverse events did not differ between nebivolol and placebo; adverse event rates were significantly lower with nebivolol than losartan (OR 0.52; p = 0.016), other beta-blockers (OR 0.56; p = 0.007), nifedipine (OR 0.49; p < 0.001), and all antihypertensive drugs combined (OR 0.59; p < 0.001).

CONCLUSION

Results of previous pharmacokinetic studies suggest that nebivolol 5 mg may not conform completely to the definition of a classic beta-blocker demonstrating additional antihypertensive effect due to endothelial NO release-mediated vasodilation. This meta-analysis showed that nebivolol 5 mg achieved similar or better rates of treatment response and BP normalization than other drug classes and other antihypertensive drugs combined, with similar tolerability to placebo and significantly better tolerability than losartan, CCAs, other beta-blockers, and all antihypertensive drugs combined. Although not definitive, this meta-analysis suggests that nebivolol 5 mg is likely to have advantages over existing antihypertensives and may have a role in the first-line treatment of hypertension.

Metabolic profile of nebivolol, a beta-adrenoceptor antagonist with unique characteristics

beta-Adrenoceptor antagonists (beta-blockers) have historically been considered an effective and safe option for first-line treatment of hypertension. However, very recently, it has been proposed that beta-blockers should no longer be considered suitable for first-line therapy in the patient with uncomplicated hypertension because of unfavourable morbidity and mortality data. New evidence from recent clinical studies of nebivolol, a third-generation highly selective beta(1)-blocker with additional endothelial nitric oxide (NO)-mediated vasodilating activity, confirms previous findings that this drug differs from other beta-blockers. The combined mechanisms of beta-adrenoceptor antagonism and NO-mediated vasodilation may potentiate the blood pressure-lowering effect of this agent, and confer a broader favourable metabolic profile, which may be clinically relevant for hypertensive patients. The antioxidant properties of nebivolol and its neutral or even favourable effects on both carbohydrate and lipid metabolism are well documented. These properties consistently differentiate nebivolol from nonvasodilating beta-blockers such as atenolol, metoprolol or bisoprolol. Therapeutic indications for beta-blockers include a wide range of co-morbidities found in hypertensive patients, including ischaemic heart disease, tachyarrhythmias and heart failure. Given that the majority of hypertensive patients require more than one drug to control blood pressure, the multiple mechanisms of action and favourable metabolic profile of nebivolol could make it an alternative therapeutic option for hypertensive patients requiring beta-adrenoceptor therapy.

Pharmacological Mechanisms of Clinically Favorable Properties of a Selective β1-Adrenoceptor Antagonist, Nebivolol

Nebivolol is a racemic mixture of d- and l-enantiomers. The drug is characterized by beta(1)-adrenoceptor selectivity and long-acting beta-blockade exerted predominantly by d-enantiomer. Nebivolol is devoid of intrinsic sympathomimetic activity and has no relevant membrane stabilizing action. Antiproliferative properties of nebivolol were demonstrated in endothelial and smooth muscle cell cultures. Infusion of nebivolol causes a vasodilation in all vascular beds by endothelial-dependent mechanism involving stimulation of beta(3)-adrenoceptors as well as by endothelial-independent mechanism. Nebivolol possesses not only direct vasodilator properties but also augments the action of endothelium-dependent vasodilators. The antioxidant property of nebivolol can at least in part explain why treatment with this drug enhances eNOS activity and minimizes the reperfusion-induced myocardial injury. The systemic effects of nebivolol in humans have an unusual hemodynamic profile. In contrast to traditional beta-adrenoceptor antagonists, nebivolol reduces preload and afterload due to systemic vasodilation and improves arterial distensibility. At 5 mg daily nebivolol effectively reduces systolic and diastolic blood pressure over a 24-h period. During treatment with nebivolol arterial pressure follows the natural circadian rhythm. Trough-to-peak ratio for nebivolol is 0.9. It has been demonstrated in numerous placebo-controlled studies that exercise tolerance is not reduced during nebivolol therapy. By chronic administration to patients with left ventricular dysfunction nebivolol increases myocardial contractility. Nebivolol produced no significant changes in lipid levels, insulin sensitivity or glucose tolerance. These findings make nebivolol a promising therapeutic tool for the treatment of arterial hypertension and chronic heart failure.

Cardiopulmonary responses and adherence to exercise in women newly diagnosed with breast cancer undergoing adjuvant therapy

Cardiopulmonary responses to an 8-week moderate-intensity aerobic exercise intervention and adherence to exercise during and after intervention were assessed in 41 women newly diagnosed with breast cancer undergoing adjuvant therapy. The intervention was primarily aimed at minimizing deconditioning. Women were randomly assigned to the intervention or control group, completed graded exercise tests before and after intervention, and encouraged to continue their exercise postintervention. Over time, only the intervention group showed significant decreases in resting heart rate, resting systolic blood pressure (SBP), P <.05 each, and maximum SBP, P <.02, and an increase in VO2 peak, P <.001, although resting SBP was higher in the intervention group at both timepoints, P <.05. The adherence rate to 8-week exercise intervention was 78.3% with average weekly attendance of 2.4 sessions and 42.7 minutes (27.8 minutes within target heart rate) exercise per session. Overall physical activity levels over 16 weeks postintervention did not differ between 2 groups. However, the within-group analysis indicated that only the intervention group showed a significant increase in voluntary activity, P < .02, and energy expenditure, P < .02, and a decrease in sedentary activity, P < .02. These findings indicate that moderate-intensity aerobic exercise is beneficial in reducing deconditioning of cardiopulmonary responses in newly diagnosed breast cancer women undergoing adjuvant therapy.

Nebivolol

Nebivolol is a third-generation beta-adrenoceptor antagonist. It differs from other beta-adrenoceptor antagonists as it combines highly selective beta(1)-adrenoceptor antagonist properties with nitric oxide-mediated vasodilatory actions and beneficial effects on endothelial function. Nebivolol is approved in Europe and several other countries for the treatment of essential hypertension and in Europe for the treatment of stable mild or moderate chronic heart failure (CHF) in addition to standard therapies in elderly patients aged >or=70 years. Nebivolol is an effective antihypertensive agent and is well tolerated in patients with hypertension. The drug also effectively decreased the composite endpoint of mortality and cardiovascular hospital admission in elderly patients with CHF and was generally well tolerated in this population. Nebivolol should be considered as an alternative first-line treatment option for patients with uncomplicated mild to moderate essential hypertension and in elderly patients with CHF.

Vasodilating beta-adrenoceptor blockers as cardiovascular therapeutics

beta-Adrenoceptor blocking agents (beta-blockers) have been established as therapeutics for treatment of patients with hypertension, ischemic heart diseases, chronic heart failure, arrhythmias, and glaucoma. However, their clinical use is limited because some patients are adversely affected by their side effects. The discovery of cardioselective (beta(1)-selective) blockers has overcome some of the problems. Current retrospective studies have revealed that vasodilating beta-blockers (so-called beta-blockers of the third generation) have advantages over the conventional type of beta-blockers in terms of minimizing the adverse effects and improving the disease-derived dysfunction, thus enhancing the quality of life variables. Some of the possible advantages include improvement of insulin resistance, decrease in low-density lipoprotein cholesterol in association with increase in high-density lipoprotein cholesterol, attenuation of bronchial asthma attack and respiratory dysfunction, alleviation of coronary vasospasm provocation, peripheral circulatory disturbances, and erectile dysfunction, and better patient compliance. Release of nitric oxide, antioxidant action, beta(2)-adrenoceptor activation, Ca(2+) entry blockade, and other mechanisms underlying the vasodilating action may be responsible for the beneficial therapeutic effects of these agents.