Hypotensive effect of atorvastatin in hypertensive patients: the association among flow-mediated dilation, oxidative stress and endothelial dysfunction

[Molecular mechanisms of the cardiotoxic action of anthracycline antibiotics and statin-induced cytoprotective reactions of cardiomyocytes]

The manifestation of the side cardiotoxic effect of anthracycline antibiotics limits their use in the treatment of malignant processes in some patients. The review analyzes the main causes of the susceptibility of cardiomyocytes to the damaging effect of anthracyclines, primarily associated with an increase in the processes of free radical oxidation. Currently, research is widely carried out to find ways to reduce anthracycline cardiotoxicity, in particular, the use of cardioprotective agents in the complex treatment of tumors. Hydroxymethylglutaryl coenzyme A reductase inhibitors (statins) have been shown to improve the function and metabolism of the cardiovascular system under various pathological impacts, therefore, it is proposed to use them to reduce cardiotoxic complications of chemotherapy. Statins exhibit direct (hypolipidemic) and pleiotropic effects due to the blockade of mevalonic acid synthesis and downward biochemical cascades that determine their cardioprotective properties. The main point of intersection of the pharmacological activity of anthracyclines and statins is the ability of both to regulate the functioning of small GTPase from the Rho family, and their effect in this regard is the opposite. The influence of statins on the modification and membrane dislocation of Rho proteins mediates the indirect antioxidant, anti-inflammatory, endothelioprotective, antiapoptotic effect. The mechanism of statin inhibition of doxorubicin blockade of the DNA-topoisomerase complex, which may be important in preventing cardiotoxic damage during chemotherapy, is discussed. At the same time, it should be noted that the use of statins can be accompanied by adverse side effects: a provocation of increased insulin resistance and glucose tolerance, which often causes them to be canceled in patients with impaired carbohydrate metabolism, so further studies are needed here. The review also analyzes data on the antitumor effect of statins, their ability to sensitize the tumor to treatment with cytostatic drug. It has been shown that the relationship between anthracycline antibiotics and statins is characterized not only by antagonism, but also in some cases by synergism. Despite some adverse effects, statins are one of the most promising cardio- and vasoprotectors for use in anthracycline cardiomyopathy.

Improved endothelial function after short-term therapy with evolocumab

BACKGROUND

The reduction of cholesterol levels with cholesterol-lowering therapy may improve endothelial function. Lipid-lowering therapy has been greatly enhanced by the introduction of proprotein convertase subtilisin/kexin type 9 (PCSK9) antibodies. Less is known of the effect of PCSK9 inhibitors on endothelial function of subjects with hypercholesterolemia.

OBJECTIVE

To assess whether treatment with PCSK9 inhibitors may improve endothelial function evaluated by brachial artery vasoreactivity test.

METHODS

Brachial artery vasoreactivity test was performed in 14 consecutive patients with previous myocardial infarction before and after 2 months of therapy with evolocumab 140 mg twice in a month. Mean brachial artery diameter, velocity time integral, flow-mediated dilation (FMD) and low-density lipoprotein (LDL) cholesterol levels were also evaluated.

RESULTS

After 2 months of treatment with evolocumab, mean total cholesterol levels decreased from 245 ± 41 to 128 ± 30 mg/dL (P < .001, -48%), and LDL levels from 176 ± 43 to 71 ± 26 mg/dL (P = .001, -59%); FMD conversely increased from 6.3 ± 4.1% to 8.8 ± 6.3% (P = .004, +40%). Improvement in FMD was proportional to reduction of LDL levels (r = 0.69, P = .006). Therapy with evolocumab increased brachial artery diameter during vasoreactivity test (peak values 0.39 ± 0.09 vs 0.36 ± 0.11 cm, P = .010; final values 0.36 ± 0.10 vs 0.34 ± 0.10 cm, P = .001), and velocity time integral (peak levels 96 ± 1 vs 85 ± 9 cm, P = .045).

CONCLUSIONS

Two months of treatment with evolocumab 140 mg may improve endothelial function in subjects with increased cardiovascular risk. The improvement in endothelial function is proportional to LDL reduction.

Statin prescribing among hypertensive patients in southwest Nigeria: findings and implications for the future

Background: Statins reduce cardiovascular risk, especially in patients with hypertension due to their concomitant blood pressure reducing effects. Prescribing generic statins minimizes cost and improves access. Aims: Ascertain current prescribing of statins in Nigeria and potential savings from the increased use of generic statins. Methods: Prospective study involving hypertensive patients attending University College Hospital (Ibadan, Nigeria). Results: In total, 228 hypertensive patients received statins. Atorvastatin was the most prescribed statin, followed by simvastatin, rosuvastatin and finally fluvastatin. Prescribed doses were less than one defined daily dose in the majority, with high use of originators. Average monthly potential savings from increased prescribing of generic statins was US$2635 for atorvastatin and US$10,578 for rosuvastatin. Conclusion: A shift toward increased prescribing generic statins is recommended to minimize costs.

Vascular endothelial function of patients with stable coronary artery disease

Objectives:

To evaluate vascular endothelial function and contributing factors in coronary heart disease (CHD) patients.

Methods:

One hundred twenty six CHD outpatients were randomly recruited. Reactive hyperemia index (RHI) <1.67 indicates endothelial dysfunction. Correlation between RHI and different biochemical parameters was evaluated.

Results:

RHI in patients receiving statins treatment was significantly higher than patients without statins treatment (P<0.05). RHI in patients with more than 3 risk factors for CHD was also markedly lower than that in patients with ≤2 risk factors (P<0.05). Patients with lesions at several branches of coronary artery had a markedly lower RHI when compared with those with coronary lesions at a single branch (P<0.05). For patients without statins treatment, RHI increased significantly after statins treatment for 1 month (P=0.01). In patients with endothelial dysfunction, FBG, HbA1C, hs-CRP and Hcy were significantly higher than those in patients with normal endothelial function (P<0.05 for all). Smokers with CHD had a remarkably lower RHI when compared with non-smokers (P<0.05).

Conclusions:

Smoking, FBG, HbA1C, Hcy and hs-CRP are significantly associated with endothelial dysfunction. Endothelial dysfunction is also related to the numbers of risk factors for CHD, degree of coronary lesions and statins. Statins treatment may significantly improve the endothelial function of CHD patients.

Response to statin therapy in obstructive sleep apnea syndrome: a multicenter randomized controlled trial

Rationale. Accumulated evidence implicates sympathetic activation as inducing oxidative stress and systemic inflammation, which in turn lead to hypertension, endothelial dysfunction, and atherosclerosis in obstructive sleep apnea (OSA). Statins through their pleiotropic properties may modify inflammation, lipid profile, and cardiovascular outcomes in OSA. Methods. This multicenter, randomized, double-blind study compared the effects of atorvastatin 40 mg/day versus placebo over 12 weeks on endothelial function (the primary endpoint) measured by peripheral arterial tone (PAT). Secondary endpoints included office blood pressure (BP), early carotid atherosclerosis, arterial stiffness measured by pulse wave velocity (PWV), and metabolic parameters. Results. 51 severe OSA patients were randomized. Key demographics for the study population were age 54 ± 11 years, 21.6% female, and BMI 28.5 ± 4.5 kg/m². In intention to treat analysis, mean PAT difference between atorvastatin and placebo groups was 0.008 (−0.29; 0.28), P = 0.979. Total and LDL cholesterol significantly improved with atorvastatin. Systolic BP significantly decreased with atorvastatin (mean difference: −6.34 mmHg (−12.68; −0.01), P = 0.050) whereas carotid atherosclerosis and PWV were unchanged compared to the placebo group. Conclusion. In OSA patients, 3 months of atorvastatin neither improved endothelial function nor reduced early signs of atherosclerosis although it lowered blood pressure and improved lipid profile. This trial is registered with NCT00669695.

Flow-mediated dilation is associated with endothelial oxidative stress in human venous endothelial cells

Flow-mediated dilation (FMD) is recognized as a non-invasive endothelial function bioassay. However, FMD's relationship with endothelial cell oxidative stress in humans is yet to be determined. Here, we sought to determine if FMD was associated with endothelial nitric oxide synthase (eNOS) and endothelial oxidative stress in humans. Twenty-seven apparently healthy young men (26.5±5.9 years) underwent brachial artery FMD testing and endothelial cell biopsy from a forearm vein. Non-normalized FMD (%) and three different brachial artery FMD normalizations were performed: (1) peak shear rate (%/SR); (2) area under the SR curve until peak dilation (%/AUC); and (3) AUC 30 seconds before peak dilation (%/AUC30). Immunofluorescence quantification was used to assess eNOS expression and nitrotyrosine (NT), a criterion marker of endothelial oxidative stress. Values for eNOS and NT expression were reported as a ratio of endothelial cell to human umbilical vein endothelial cell average pixel intensity. NT expression was significantly correlated with FMD normalized by AUC30 (r = -0.402, p<0.05). Other FMD normalizations and non-normalized FMD were not significantly correlated with NT expression (r range = -0.364 to -0.142, all p>0.05). There were no significant correlations between eNOS expression and normalized and non-normalized FMD (r range = -0.168 to -0.066, all p>0.05). In conclusion, brachial artery FMD is associated with venous endothelial cell oxidative stress. However, this association is observed only when FMD is normalized by AUC30.

Lipid, blood pressure and kidney update 2013

The year 2013 proved to be very exciting as far as landmark trials and new guidelines in the field of lipid disorders, blood pressure and kidney diseases. Among these are the International Atherosclerosis Society Global Recommendations for the Management of Dyslipidemia, European Society of Cardiology (ESC)/European Society of Hypertension Guidelines for the Management of Arterial Hypertension, American Diabetes Association Clinical Practice Recommendations, the Kidney Disease: Improving Global Outcomes Clinical Practice Guidelines for Managing Dyslipidemias in Chronic Kidney Disease (CKD) Patients, the American College of Cardiology/American Heart Association Guideline on the Treatment of Blood Cholesterol to Reduce Atherosclerotic Cardiovascular Risk in Adults, the Joint National Committee Expert Panel (JNC 8) Evidence-Based Guideline for the Management of High Blood Pressure in Adults, the American Society of Hypertension/International Society of Hypertension Clinical Practice Guidelines for the Management of Hypertension in the Community, the American College of Physicians Clinical Practice Guideline on Screening, Monitoring, and Treatment of Stage 1-3 CKD and many important trials presented among others during the ESC Annual Congress in Amsterdam and the American Society of Nephrology Annual Meeting--Kidney Week in Atlanta, GA. The paper is an attempt to summarize the most important events and reports in the mentioned areas in the passing year.

The effects of statins on blood pressure in normotensive or hypertensive subjects--a meta-analysis of randomized controlled trials

OBJECTIVE

The aim of this meta-analysis was to investigate whether statin therapy is associated with blood pressure (BP)-lowering in patients with or without hypertension.

BACKGROUND

The beneficial effects of statins on the cardiovascular system may in part be related to effects beyond lipid-lowering. It has been suggested that statins may reduce BP; however the available data are still ambiguous and often conflicting.

METHODS

Data from Scopus, PubMed, Web of Science, and the Cochrane Central Register of Controlled Trials for the years 1966-January 2012 were searched for studies that investigated the effect of statins on BP in normotensive or in hypertensive subjects. We included all randomized controlled clinical trials that investigated this effect. Changes in systolic and diastolic BP were the key outcomes of interest.

RESULTS

The final analysis included 18 trials and 5628 subjects (4692 normotensive and 936 hypertensive patients) randomized to receive either statins or placebo. The weighted mean difference of systolic (∆SBP) and diastolic blood pressure (∆DBP) in normotensive patients for the 11 statin trials included were 0.03 (95% CI: -0.95-1.02; p = 0.95) and -0.28 (95% CI: -0.80-0.24; p = 0.29), respectively. For hypertensive patients treated with statins (8 trials) the weighted mean difference of ∆SBP and ∆DBP were 1.45 (95% CI: -0.49-3.39; p = 0.14) and -1.32 (95% CI: -3.93-1.28; p = 0.32) respectively.

CONCLUSIONS

Despite previous suggestions statin therapy in normotensive or hypertensive patients does not lead to significant reductions in systolic or diastolic BP.

The effect of combining rosuvastatin with sartans of different peroxisome proliferator receptor-γ activating capacity on plasma 8-isoprostane prostaglandin F2a levels

INTRODUCTION

Oxidative stress is associated with the development and progression of cardiovascular disease. Plasma 8-isoprostane prostaglandin F2a (8-iso-PGF2a) levels are a reliable marker of oxidative stress.

MATERIAL AND METHODS

Patients (n = 151) with hypertension, dyslipidemia and impaired fasting glucose were randomly allocated to rosuvastatin (10 mg/day) plus telmisartan 80 mg/day (RT group, n = 52) or irbesartan 300 mg/day (RI group, n = 48) or olmesartan 20 mg/day (RO group, n = 51). After 6 months of treatment, changes in plasma 8-iso-PGF2a levels were blindly evaluated.

RESULTS

A decrease of 8-iso-PGF2a levels vs baseline was observed only in the RT group (-8.6%; p = 0.02). A trend for decrease vs. baseline was observed in the RI (-5.7%; p = 0.40) and RO (-3.7%; p = 0.60) groups. Changes of 8-iso-PGF2a levels between groups were not significantly different (p = 0.70).

CONCLUSIONS

The combination of rosuvastatin with sartans of different peroxisome proliferator receptor-γ activating capacity was associated with a decrease in levels of plasma 8-iso-PGF2a. This decrease reached significance only in the telmisartan group.