[Comparative analysis of antioxidant activity of nebivolol in patients with chronic heart failure with and without concomitant type 2 diabetes]

Consistent neurohormonal activation of sympatho-adrenal system in patients with chronic heart failure (CHF) and hyperglycemia contributes to development of oxidative stress--one of the most important pathogenetic mechanisms of endothelial dysfunction.

PURPOSE

To study the impact of nebivolol concerning modification of clinical and hemodynamic indicators and parameters of oxidative stress in patients with CHF and with or without concomitant diabetes mellitus type 2 (DM2).

MATERIAL

Nebivolol was used in complex therapy of CHF in 82 patients, suffering from NYHA class I - III CHF (EF < 50%) of ischemic genesis with or without comorbid DM2, average age 63.2 +/- 8.2 years.

RESULTS

After 8 months of therapy significant improvement of clinical status was observed in both groups, tolerance to physical activity increased (significant reduction of average class of CHF in the group with DM2 from 2.5 +/- 0.58 to 2.125 +/- 0.71, p = 0.001, and in the second group from 2.3 +/- 0.5 to 1.9 +/- 0.4, p = 0.01). We also noted in both groups increase of plasma oxidative resistance (reduction of intensity of fast flash in lipid peroxidation h from 7 to 6 mm, p = 0.016, and from 8 to 6 mm, p = 0.03, respectively) and increase of antioxidant plasma protection (increase of SH-groups from 154.19 to 182.4 mmol/1, p = 0.00035, and from 176 to 205, p = 0.004, respectively).

CONCLUSION

Nebivolol is a modern neurohormonal modulator, which contributes to reverse evolution of oxidative changes in patients with CHF and hyperglycemia.

Salt-induced renal injury in spontaneously hypertensive rats: effects of nebivolol

BACKGROUND

we investigated renal effects of nebivolol, a selective β(1)-receptor blocker with additional antioxidative ability, in spontaneously hypertensive rats (SHR) where increased salt intake induces oxidative stress and worsens renal function as a result of further activation of the renin-angiotensin and sympathetic nervous systems.

METHODS

male SHR were given an 8% salt diet (HS; n = 22) for 5 weeks; their age-matched controls (n = 9) received standard chow. Nebivolol was given at a dose of 10 mg/kg/day for 5 weeks in 11 HS rats.

RESULTS

HS increased blood pressure, plasma renin concentration, urinary protein excretion, and renal nitroxidative stress while decreasing renal blood flow and angiotensin 1-7 receptor (mas) protein expression. There was no change in angiotensin II type 1 receptor expression among the experimental groups. Nebivolol did not alter the salt-induced increase in blood pressure but reduced urinary protein excretion, plasma renin concentration, and nitroxidative stress. Nebivolol also increased neuronal NOS expression while preventing the salt-induced decrease in renal blood flow and mas protein expression.

CONCLUSION

nebivolol prevented salt-induced kidney injury and associated proteinuria in SHR through a blood pressure-independent mechanism. Its protective effects may be related to reduction in oxidative stress, increases in neuronal NOS and restoration of angiotensin II type 1/mas receptor balance.

[Effect of brazilein on energy metabolism of cerebral ischemia-reperfusion in mice]

OBJECTIVE

To investigate brazilein's role in energy metabolism of cerebral ischemia-reperfusion in mice.

METHOD

Fourty mice were randomly divided into the sham group, ischemia group, brazilein 5 mg x kg(-1) group and brazilein 10 mg x kg(-1) group, each with ten cases. Cerebral ischemia model was the built. Mice were injected with brazilein three days before the operation, then they were killed. Cerebrum homogenate was prepared for the detecting of ATP, ADP, AMP and lactic acid by HPLC, expressions of MCT1 and MCT2 in mRNA level by RT-PCR.

RESULT

The lactic acid in cerebrum increased sharply 20 minutes after cerebral ischemia and decreased 1 hour after reperfusion, then returned to the normal level 24 hours after reperfusion. The charge of energy decreased significantly at the beginning of the ischemia-reperfusion, and the charge restored 1 hour after reperfusion though it was still much lower than the normal level at the time point of 24 hours. Moreover, MCT1 and MCT2 upregulated accompanied with the increase of lactate, MCT2 mRNA enhanced in brazilein 5 mg x kg(-1) group (P < 0.05) while both the two factors increased in brazilein 10 mg x kg(-1) group (P < 0.01).

CONCLUSION

Brazilein might protect neurons by changing the charge of energy.

Comparison of the effects of nebivolol and valsartan on BP reduction and sleep apnoea activity in patients with essential hypertension and OSA

OBJECTIVES

To investigate the effect of nebivolol, a third generation beta-blocker, on blood pressure (BP) reduction and polysomnographic parameters in hypertensive patients with mild-to-moderate obstructive sleep apnoea (OSA).

METHODS

In this double-blind, parallel group study, patients were randomized to nebivolol 5 mg or valsartan 80 mg once daily following a 14-day, placebo run-in period during which any antihypertensive medication were discontinued. BP and heart rate measurements and overnight polysomnography were performed at baseline and after 6 weeks of treatment. Safety and tolerability were assessed.

RESULTS

Thirty-one patients were randomized to nebivolol (n = 16) or valsartan (n = 15). After six weeks both systolic and diastolic BP were effectively reduced by both treatments. Reductions in BP were not statistically significant different between agents, but mean heart rate was significantly decreased with nebivolol (compared with valsartan (p < 0.001). There was no statistically significant difference between both treatments for the change from baseline to treatment end for mean (+/-SD) Apnoea Hypopnoea Index (AHI) (nebivolol: 23.0 +/- 9.2 to 27.9 +/- 21.2 events/h; valsartan: 23.8 +/- 6.6 to 22.5 +/- 18.0 events/h; p = 0.48) or for any other sleep-related parameters. Both agents were well tolerated.

CONCLUSION

Nebivolol has a significant BP reduction effect in patients with OSA that is similar to valsartan and reduces heart rate to a greater extent which may prove beneficial in selected patients.

[Preparation of sustained-release capsules of zaltoprofen]

OBJECTIVE

To prepare sustained-release capsule of Zaltoprofen (ZP).

METHODS

The pellets containing ZP were prepared in the fluid-bed by suspension layering and then coated with ethylcellulose (EC) and hydroxy-propyl methyl cellulose (HPMC). The quality and micromeritics of the ZP pellets were evaluated. The release profile of the AP pellets and the effects of thermal treatment and artificial gastric juice on the release profile were tested.

RESULTS

The surface of the coated pellets was smooth, glossy and round. No obvious effect of thermal treatment on the release profile was observed, indicating that thermal treatment on the ZP sustained release capsule is not necessary. The effect of artificial gastric juice on the release profile was significant, indicating that the ZP sustained release capsule should be put into enteric capsule. The release rate of ZP showed lot-in-lot and lot-to-lot uniformity. The dissolution profiles of ZP from the pellets fit into a first grade equation.

CONCLUSION

The pellets exhibit ideal sustained-release characteristics in vitro.

Clinical pharmacodynamics of nebivolol: new evidence of nitric oxide‐mediated vasodilating activity and peculiar haemodynamic properties in hypertensive patients

New evidence from recently completed clinical studies performed with nebivolol, a highly selective beta-1 beta-blocker, endowed with additional vasodilating activity mediated by nitric oxide (NO) endothelial release, confirm previous findings that nebivolol differs from other beta-blocking agents and that the combination of beta-1 blockade and NO-mediated vasodilation not only potentiates the blood pressure lowering activity, but leads to a broader favourable haemodynamic profile, which is clinically relevant to the treatment of hypertensive patients. In particular, six new studies focusing on the vasodilation properties of nebivolol demonstrated that: (i) its blood pressure lowering effect is accompanied by a vasodilating action that is seen after single and chronic administration of the usual antihypertensive oral dose of 5 mg once daily; (ii) the vasodilation can be documented systemically, at various regional vascular beds and skin microcirculation, and is accompanied by increased small arterial distensibility; (iii) the NO-endothelium-dependency of its vasodilating action is shown by the model of forearm or cutaneous vasodilating response to acetylcholine and by the blockade of the nebivolol-induced local vasodilation by a blocker of the arginine-NO cascade, L-NMMA. Two more studies demonstrated the ability of nebivolol to increase NO concentrations through preservation of NO from oxidative degradation, and not only by stimulation of its synthesis. Finally, two studies confirmed the favourable haemodynamic action of nebivolol on both systolic and diastolic function and, in particular, an increase in stroke volume, associated with reduction in vascular resistance, resulting in a maintained cardiac output despite reduced heart rate. These properties consistently differentiate nebivolol from non-vasodilating beta-blockers, such as those used for the active comparative studies, i.e. atenolol, metoprolol or bisoprolol. The observation that nebivolol enhances or restores NO-mediated vasodilation in hypertensive patients has important therapeutic implications in view of the well-established protective role of NO against cardiovascular risk factors, and particularly the development of atherosclerosis. Similarly, the favourable haemodynamic profile of nebivolol, as described by the new investigations (preservation of cardiac output, reduction of peripheral resistance and improved diastolic function) appear to have clinically relevant benefits on the impairment in systolic and/or diastolic function often complicating the hypertension.

Behavioral effects of acute and chronic oral administration of barakol in rats

INTRODUCTION

Barakol, an active constituent extracted from Cassia siamea, has been shown to have anxiolytic effects similar to diazepam when treated intraperitoneally.

OBJECTIVE

Acute and chronic oral administrations of barakol on anxiolytic, locomotor and exploratory behaviors were examined in rats using an elevated plus maze followed by a holeboard apparatus in comparison with the anxiolytic diazepam.

MATERIAL AND METHOD

Male Wistar rats were divided into the acute and chronic treatment groups. The acutely-treated rats were given orally with vehicle control (distilled water, p.o.), diazepam (5 mg/kg, p.o.) and barakol (10, 30 and 100 mg/kg, p.o.) while the chronically-treated rats received the same treatment for 30 consecutive days. The anxiolytic behavior was tested on the elevated plus maze for 5 min and immediately followed by the holeboard to test for the directed exploratory behavior for 10 min.

RESULTS

Acute and chronic oral administration of barakol (10, 30 and 100 mg/kg, p.o.) produced no significant changes in anxiolytic parameters tested on the elevated plus maze compared to diazepam which significantly increased the percentage of the open/total time and the time spent on the open arms. On the other hand, all parameters tested using the holeboard were not affected by barakol or diazepam when given acutely. When given chronically, all doses of barakol significantly decreased the number of head-dips and the total time spent head-dipping with no changes in the number of grooms or rears per minute.

CONCLUSION

Acute and chronic oral administration of barakol had no anxiolytic and locomotor effects. However, it exerted a sedative effect as shown by a reduction in the directed exploratory behaviors.

[Correction of portal hypertension and renal dysfunction with help of nebivolol and lizinopril in patients with hepatic cirrhosis]

The effect of nebevolol, beta-blocker on the portal hypertension and renal blood flow and the safety of its use versus lisinopril, an angiotensin-converting enzyme inhibitor were examined in the patients with cirrhosis. 72 patients were examined (39 patients with cirrhosis of the liver without ascites - the 1st group and 32 patients with cirrhosis of the liver with ascites - the 2nd group. Trustworthy decrease of portal hypertension parameters (the decrease of portovenosis gradient of pressure (PPG) by 19,3% (p = 0,048) in the patients with liver cirrhosis of class A on Child-Pugh without ascites with nebevolol was revealed. The trust worthy changes of portal blood flow was not revealed in all examined patients with lisinopril. But these patients without ascites have demonstrated the improvement of the renal hemodynamic (renal functional reserve (RFR) by 56%, effective renal plasma flow (ERPF) by 17,3%). The lisinopril intake 5 mg a day declines PPG by 18,1%. The tendency of the reduction of the functional index due to the expressed hypotensive effect of nebevolol and lisinopril was revealed in all examined patients with liver cirrhosis. So it was demonstrated that for the management of the portal hypertension in the patients with liver cirrhosis is necessary to examine of functional renal condition to prevent the development of hepatorenal syndrome.

[Optimization of use of beta-adrenoblockers in the treatment of chronic heart failure in the outpatient setting]

AIM

to evaluate of the effectiveness of switching from beta-adrenoblockers (BAB) non-included into the guidelines for the management of chronic heart failure (CHF) to nebivolol and bisoprolol for outpatients.

SUBJECTS AND METHODS

The study included 67 patients with stable Functional Classes (FC) II and II CHF who received the standard therapy and BAB non-included into the guidelines for the management of CHF. The patients were randomized to the groups taking bisoprolol (n = 35) or nebivolol (n = 32) in doses of 1.25 to 10 mg/day. Before and 6 months after therapy, the investigators assessed the patient's clinical status and quality of life (QL), performed a six-minute walk test and echography, and determined the blood level of the N-terminal fragment of brain natriuretic peptide prohormone (NT-proBNP).

RESULTS

The switching to bisoprolol and nebivolol was followed by a significant clinical improvement, a larger covered distance, and better QL. Left ventricular ejection fraction was increased along with a reduction in mean FC CHF. There were no significant changes in NT-proBNP in the total patient group, but it was significantly decreased in the subgroup of those with the baseline high level of the peptide.

CONCLUSION

The switching of patients with stable CHF from therapy with BAB not included into the guidelines for the management of CHF to nebivolol or bisoprolol yields positive results and improves left ventricular systolic function (which is attended by the reduction in NT-proBNP levels) and may be recommended for treatment in the outpatient setting.

Randomized, double-blind, placebo-controlled trial of the 5-HT1A receptor antagonist AZD7371 tartrate monohydrate (robalzotan tartrate monohydrate) in patients with irritable bowel syndrome

OBJECTIVES

To investigate the efficacy and safety of the 5-hydroxytrypamine 1A (5-HT(1A)) receptor antagonist AZD7371 tartrate monohydrate (robalzotan tartrate monohydrate), termed AZD7371 here, in patients with irritable bowel syndrome (IBS).

METHODS

Patients meeting the Rome II criteria for IBS (N = 402) were randomized to treatment with AZD7371 20 mg or 5 mg or matching placebo tablets twice daily for 12 wk. The patients completed daily and weekly diary assessments, reporting abdominal discomfort or pain and description of bowel movements. They also completed validated symptom and quality-of-life questionnaires.

RESULTS

Neither AZD7371 regimen was significantly more effective than placebo in providing adequate relief from IBS symptoms in at least 2 out of 4 wk per month over the 12 wk of treatment. There was also no significant difference between the treatment groups and placebo in the change in score in the validated symptom and quality-of-life questionnaires. Overall, 22.1% of patients experienced adverse events (AEs) attributed to the study medication: 44 of 133 (33.1%) in the 20 mg AZD7371 group, 27 of 131 (20.6%) in the 5 mg AZD7371 group, and 17 of 134 (12.7%) in the placebo group. Also, 31 of 57 (54%) of AEs leading to discontinuation were central nervous system-related. Hallucinations or hallucination-like AEs were reported by eight patients taking AZD7371, and by none of the patients in the placebo group. After these events led to discontinuation in six patients, the study was prematurely terminated.

CONCLUSIONS

In view of the AE profile and lack of efficacy in IBS, the clinical development of AZD7371 has been stopped.

Hypothalamic protein kinase C regulates glucose production

OBJECTIVE

A selective rise in hypothalamic lipid metabolism and the subsequent activation of SUR1/Kir6.2 ATP-sensitive K(+) (K(ATP)) channels inhibit hepatic glucose production. The mechanisms that link the ability of hypothalamic lipid metabolism to the activation of K(ATP) channels remain unknown.

RESEARCH DESIGN AND METHODS

To examine whether hypothalamic protein kinase C (PKC) mediates the ability of central nervous system lipids to activate K(ATP) channels and regulate glucose production in normal rodents, we first activated hypothalamic PKC in the absence or presence of K(ATP) channel inhibition. We then inhibited hypothalamic PKC in the presence of lipids. Tracer-dilution methodology in combination with the pancreatic clamp technique was used to assess the effect of hypothalamic administrations on glucose metabolism in vivo.

RESULTS

We first reported that direct activation of hypothalamic PKC via direct hypothalamic delivery of PKC activator 1-oleoyl-2-acetyl-sn-glycerol (OAG) suppressed glucose production. Coadministration of hypothalamic PKC-delta inhibitor rottlerin with OAG prevented the ability of OAG to activate PKC-delta and lower glucose production. Furthermore, hypothalamic dominant-negative Kir6.2 expression or the delivery of the K(ATP) channel blocker glibenclamide abolished the glucose production-lowering effects of OAG. Finally, inhibition of hypothalamic PKC eliminated the ability of lipids to lower glucose production.

CONCLUSIONS

These studies indicate that hypothalamic PKC activation is sufficient and necessary for lowering glucose production.

Development and validation of a stability-indicating column high-performance liquid chromatographic assay method for determination of nebivolol in tablet formulation

A simple, precise, and accurate isocratic reversed-phase (RP) stability-indicating column high-performance liquid chromatographic (HPLC) assay method was developed and validated for determination of nebivolol in solid pharmaceutical dosage forms. Isocratic RP-HPLC separation was achieved on a Phenomenex Luna C8 (2) column (250 mm x 4.6 mm id, 5 microm particle size) using mobile phase composed of acetonitrile-pH 3.5 phosphate buffer (35 + 65, v/v) at a flow rate of 1.0 mL/min, and detection was performed at 280 nm using a photodiode array detector. The drug was subjected to oxidation, hydrolysis, photolysis, and heat to apply stress conditions. The method was validated for specificity, linearity, precision, accuracy, robustness, and solution stability. The method was linear in the drug concentration range of 40-160 microg/mL with a correlation coefficient of 0.9999. The repeatability relative standard deviation (RSD) for 6 samples was 0.69%, and the intermediate precision (RSD) for 6 samples was 1.39%. The accuracy (recovery) was between 98.57 and 99.55%. Degradation products produced as a result of stress studies did not interfere with detection of nebivolol, and the assay can thus be considered stability-indicating.

[Comparison of effects of nebivolol and atenolol on P-wave dispersion in patients with hypertension]

BACKGROUND

P-wave dispersion has been shown to be a noninvasive electrocardiographic predictor for development of atrial fibrillation . Thus it may be possible to attenuate atrial fibrillation risk through normalization of P-wave variables and improvement in P-wave dispersion may be an important goal in treatment of hypertension.

OBJECTIVE

To compare the effects of nebivolol, a new b-blocker that have additional vasodilating activity via acting on endothelium and nitric oxide release, and atenolol on P-wave duration and dispersion in patients with mild-to-moderate hypertension.

METHODS

A total of 34 newly-diagnosed hypertensive patients were enrolled in the study. The patients were randomly assigned to receive treatment with either nebivolol (5 mg) or atenolol (50 mg). P-wave durations (Pmin and Pmax) and P-wave dispersion were measured before and one month after treatment.

RESULTS

While Pmin increased (50,6 +/- 11,2 ms to 54,7 +/- 9,1 ms, p=0,05), Pmax decreased (111,9 +/- 9,1 ms to 104,0 +/- 12,4 ms, p=0,003) and P-wave dispersion decreased (62,5 +/- 10,6 ms to 51,3 +/- 8,9 ms, p < 0,001) with nebivolol, Pmin increased (44,4 +/- 9,8 ms to 58,0 +/- 15,5 ms, p=0,02), Pmax didn t change (106,1 +/- 13,8 ms to 107,0 +/- 11,6 ms, p=NS) and P-wave dispersion decreased (61,7 +/- 15,0 ms to 49,0 +/- 13,7 ms, p < 0.001) with atenolol. However, there was no statistical difference between pre- and post-treatment values of two groups.

CONCLUSIONS

Both nebivolol and atenolol are effective in improvement of P-wave dispersion in patients with hypertension and there s no significant difference between them.

[Heart rate variability dynamics during treatment of arterial hypertension]

Investigation of the dynamics of heart rate variability (HRV) in anti-hypertension therapy can facilitate the evaluation of the effectiveness of treatment.

AIM OF INVESTIGATION

to compare anti-hypertension effect of monotherapy with nebivolol and dilatrend with dynamics of HRV and the estimation of the state of patients with mild arterial hypertension (AH) and metabolic syndrome (MS).

MATERIAL AND METHODS

HRV was studied in 42 patients with mild AH and MS at the age of 32-60. Eighteen of them were treated with 5 mg of nebivolol during 24 weeks, and twenty-four with 25-50 mg of dilatrend during 16 weeks. All the patients were subjected to 24-hour ECG monitoring with analysis of HRV and arterial pressure (AP) before and after treatment. The main feature of HRV analysis was investigation of dependence of sinus arrhythmia on the mean value of heart rate (HR) RESULTS: With nebivolol treatment AP decreased in 11 patients, HRV became better in 9 patients. 7 cases manifested coincidence of AP reduction and HRV improvement. In 6 cases out of 7 when AP did not decrease, HRV did not change. Worsened HRV was observed in 3 cases: in one case with growing AP and in 2 cases with decreasing AP. All the patients, except one, regarded their state as improved. With dilatrend treatment AP lowered in 16 cases. In 9 cases HRV became better, in 11 cases it remained the same, and in 4 cases it became worse. Positive HRV dynamics in 7 cases out of 9 was accompanied by lowering of AP, while negative dynamics was observed in one case with rise of AP and in three cases with very low AP or in the absence of AP dynamics. 14 patients felt better, 6 of them manifested better level both of AP and HRV.

CONCLUSION

The method of 24-hour HRV analysis based on assessment of dependence of the value of sinus arrhythmia on HR is useful in evaluating the effectiveness of anti-hypertension therapy. As a rule, an effective decrease in AP is accompanied with improvement of HRV. The absence of improvement of deterioration of HRV in anti-hypertension therapy is a factor which should be taken into consideration when choosing the mode of therapy.

[Clinico-immunological disorders in patients with ischemic heart disease combined with metabolic syndrome and modulating effect of nebivolol for their correction]

AIM

To evaluate clinico-immunological disorders in patients with ischemic heart disease (IHD) and metabolic syndrome (MS), to study an immunocorrective action of nebivolol during 6-month treatment.

MATERIAL AND METHODS

A total of 54 patients with postinfarction left ventricular dysfunction and chronic cardiac failure of NYHA functional class II-III were divided into two groups: group 1 (n=24) comprised patients with effort angina FC II-III and impaired glucose tolerance, group 2 (n=30) consisted of anginal patients associated with type 2 diabetes mellitus (DM). Clinical, laboratory and functional indices were registered before therapy with nebivolol and 6 months after it. Immunological control included determination of the subpopulation composition of lymphocytes, immunoglobulins, circulating immune complexes (CIC), antibodies to cardiolipin (CL), proinflammatory cytokines: IL-1alpha, IL-2, IL-6, IL-8, alpha-interferon, tumor necrosis factor alpha (TNFalpha).

RESULTS

Nebivolol demonstrated good antihypertensive and anti-ischemic cardioprotective efficacy in IHD patients with MS, it did not deteriorate atherogenic dyslipidemia and impaired carbohydrate metabolism. As a good immunocorrector, nebivolol significantly inhibited cytokine overactivation, had a weak effect on dysimmunoglobulinemia, CIC level and expression to CL antibodies. Side effects were not recorded.

CONCLUSION

IHD patients with MS (especially patients with type 2 DM) have manifest immune disorders presenting with overactivation of proinflammatory cytokines with high levels of IgA, IgG, CIC and antibodies to CL in the presence of low immunoregulatory index. Nebivolol provided good control of arterial hypertension, myocardial ischemia, positive changes in immunological indices, improved intracardiac hemodynamics.

[Clinical efficacy of ivabradin and nebivolol addition in combined treatment of ischemic heart disease patients with left ventricular dysfunction]

AIM

To assess ivabradin and nebivolol efficacy in combined treatment of ischemic heart disease patients with chronic heart failure (CHF) of functional class (FC) II-III by NYHA, impact of these drugs on quality of life, circadian indices of myocardial ischemia (CMI), left ventricular (LV) contractility.

MATERIAL AND METHODS

A total of 92 patients with CHF of FC II-III (mean age 57.3 +/- 4.5 years) were randomized into 3 groups. Patients of group 1 (n = 30) received combined basic therapy: inhibitors of ACE, diuretics, aspirin, statins, on demand nitrates. Patients of group 2 (n = 33) received basic combined treatment plus nebivolol (nebilet, Berlin-Chemie/Menarini) in a dose 5.0 mg/day. Group 3 (n = 29) was given basic therapy plus ivabradin (coraxan) in a mean dose 7.5 mg.

RESULTS

The addition of ivabradin and nebivolol to combined treatment of ischemic heart disease with LV dysfunction brought about control over heart rate (HR), improved quality of life, reduced severity of CHF, CMI, number of episodes of painful and painless ischemia. In reduced by nebivolol HR addition of ibavradin improved systolic and diastolic LV function. The analysis of HR variability in ivabradin administration showed enhancement of parasympathic activity in the vegetative balance. Administration of nebivolol produced modulated attenuation of sympathic activity.

CONCLUSION

Addition of ivabradin and nebivolol to combined treatment of ischemic heart disease with LV dysfunction raises efficacy of treatment.

Effect of nebivolol and metoprolol treatments on serum asymmetric dimethylarginine levels in hypertensive patients with type 2 diabetes mellitus

OBJECTIVE

Elevated asymmetric dimethylarginine (ADMA) levels, an endogenous inhibitor of nitric oxide synthase, are an important cardiovascular risk factor. In patients with diabetes, increased ADMA levels have been reported, which may be associated with endothelial dysfunction. In this study, effect of nebivolol on serum ADMA levels in hypertensive patients with type 2 diabetes have been compared with metoprolol, an another beta-blocker.

METHODS

A total of 54 patients (27 female, 27 male; mean age: 53.0+/-8.7 years) with type 2 diabetes and hypertension were included in this randomized, open-label, prospective study. Patients were randomized to receive either nebivolol 5 mg/day (n=28) or metoprolol 100 mg/day (n=26) for 12 weeks. When the patients could not reach target blood pressure levels at the end of week 4, indapamide (2.5 mg/day) was added. Enzyme Linked Immunosorbent Assay was used for serum ADMA measurements.

RESULTS

Similar reductions in blood pressure values were observed in both groups (p>0.05). In nebivolol group, there were no significant changes in serum ADMA levels compared to baseline (0.6+/-0.2 micromol/l vs 0.6+/-0.1 micromol/l, p>0.05), whereas in metoprolol group a 35.6% increase in serum ADMA levels was observed (0.6+/-0.1 micromol/l vs 0.7+/-0.2 micromol/l, p<0.01).

CONCLUSION

We observed a significant increase in ADMA levels, a marker of endothelial dysfunction, during metoprolol treatment, whereas nebivolol had neutral effects on ADMA levels in patients with type 2 diabetes mellitus and hypertension.

Antiestrogenic glyceollins suppress human breast and ovarian carcinoma tumorigenesis

PURPOSE

We have identified the phytoalexin compounds glyceollins I, II, and III, which exhibit marked antiestrogenic effects on estrogen receptor function and estrogen-dependent tumor growth in vivo. The purpose of this study was to investigate the interactions among the induced soy phytoalexins glyceollins I, II, and III on the growth of estrogen-dependent MCF-7 breast cancer and BG-1 ovarian cancer cells implanted in ovariectomized athymic mice.

EXPERIMENTAL DESIGN

Four treatment groups for each cell line were used: vehicle control, 20 mg/kg/mouse/d glyceollin mixture injection, 0.72 mg estradiol (E2) implant, and E2 implant + 20 mg/kg/mouse/d glyceollin injection.

RESULTS

Treatment with glyceollin suppressed E2-stimulated tumor growth of MCF-7 cells (-53.4%) and BG-1 cells (-73.1%) in ovariectomized athymic mice. These tumor-inhibiting effects corresponded with significantly lower E2-induced progesterone receptor expression in the tumors. In contrast to tamoxifen, the glyceollins had no estrogen-agonist effects on uterine morphology and partially antagonized the uterotropic effects of estrogen.

CONCLUSIONS

These findings identify glyceollins as antiestrogenic agents that may be useful in the prevention or treatment of breast and ovarian carcinoma.

Does the beta-blocker nebivolol increase coronary flow reserve?

INTRODUCTION

Nebivolol, a highly selective beta1-adrenergic receptor-blocker, increases basal and stimulated endothelial nitric oxide (NO)-release. It is unknown, whether coronary perfusion is improved by the increase in NO availability. Therefore, we sought to evaluate the effect of nebivolol on coronary flow reserve (CFR) and collateral flow.

METHODS

Doppler-flow wire derived coronary flow velocity measurements were obtained in ten controls and eight patients with coronary artery disease (CAD) at rest and after intracoronary nebivolol. CFR was defined as maximal flow during adenosine-induced hyperemia divided by resting flow. In the CAD group, collateral flow was determined after dilatation of a flow-limiting coronary stenosis. Collateral flow index (CFI) was defined as the ratio of flow velocity during balloon inflation divided by resting flow.

RESULTS

CFR at rest was 3.0+/-0.6 in controls and 2.1+/-0.4 in CAD patients. After intracoronary doses of 0.1, 0.25, and 0.5 mg nebivolol, CFR increased to 3.4+/-0.7, 3.9+/-0.9, and 4.0+/-0.1 (p<0.01) in controls, and to 2.3+/-0.7, 2.6+/-0.9, and 2.6+/-0.5 (p<0.05) in CAD patients. CFI decreased significantly with intracoronary nebivolol and correlated to changes in heart rate (r=0.75, p<0.001) and rate-pressure product (r=0.59, p=0.001).

DISCUSSION

Intracoronary nebivolol is associated with a significant increase in CFR due to reduction in resting flow (controls), or due to an increase in maximal coronary flow (CAD patients). CFI decreased with nebivolol parallel to the reduction in myocardial oxygen consumption.