Downregulation of angiotensin II type 1 receptor by hydrophobic 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors in vascular smooth muscle cells

Increased Expression of Mevalonate Pathway-Related Enzymes in Angiotensin II-Induced Abdominal Aortic Aneurysms

Abdominal aortic aneurysm (AAA) is characterized by permanent luminal expansion and a high mortality rate due to aortic rupture. Despite the identification of abnormalities in the mevalonate pathway (MVA) in many diseases, including cardiovascular diseases, the potential impact of this pathway on AAA remains unclear. This study aims to investigate whether the expression of the MVA-related enzyme is altered during the progression of angiotensin II (Ang II) -induced AAA.Ang II 28D and Ang II 5D groups were continuously perfused with Ang II for 28 days and 5 days, respectively, and the Sham group was perfused with saline. The general and remodeling characteristics of AAA were determined by biochemical and histological analysis. Alteration of MVA-related enzyme expressions was revealed by western blot and single-cell RNA sequencing (scRNA-seq).The continuous Ang II infusion for 28 days showed significant aorta expansion and arterial remodeling. Although the arterial diameter slightly increased, the aneurysm formation was not found in Ang II induction for 5 days. MVA-related enzyme expression and activation of small GTP-binding proteins were significantly increased after Ang II-induced. As verified by scRNA-seq, the key enzyme gene expression was also higher in Ang II 28D. Similarly, it was detected that the expression levels of the above enzymes and the activity of small G proteins were elevated in the early stage of AAA as induced by Ang II infusion for 5 days.Continuous Ang II infusion-induced abdominal aortic expansion and arterial remodeling were accompanied by altered expression of key enzymes in the MVA.

Understanding the molecular mechanisms of statin pleiotropic effects

Statins represent the cornerstone of pharmacotherapy for the prevention of atherosclerotic cardiovascular disease. These medications not only reduce low-density lipoprotein cholesterol (LDL-C) via inhibition of 3-hydroxy-3-methylglutarate attached to CoA reductase, the key rate-limiting step in the cholesterol biosynthetic pathway, but also upregulate expression of the low-density lipoprotein receptor, improving serum clearance. Given LDL-C is a causal risk factor for the development of atherosclerosis, these complementary mechanisms largely explain why statin therapy leads to reductions in major adverse cardiovascular events. However, decades of basic and clinical research have suggested that statins may exert other effects independent of LDL-C lowering, termed pleiotropic effects, which have become a topic of debate among the scientific community. While some literature suggests statins may improve plaque stability, reduce inflammation and thrombosis, decrease oxidative stress, and improve endothelial function and vascular tone, other studies have suggested potential harmful pleiotropic effects related to increased risk of muscle-related side effects, diabetes, hemorrhagic stroke, and cognitive decline. Furthermore, the introduction of newer, non-statin LDL-C lowering therapies, including ezetimibe, proprotein convertase subtilisin/Kexin Type 9, and bempedoic acid, have challenged the statin pleiotropy theory. This review aims to provide a historical background on the development of statins, explore the mechanistic underpinnings of statin pleiotropy, review the available literature, and provide up to date examples that suggest statins may exert effects outside of LDL-C lowering and the cardiovascular system.

Beyond Lipid-Lowering: Effects of Statins on Cardiovascular and Cerebrovascular Diseases and Cancer

The 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors, also known as statins, are administered as first-line therapy for hypercholesterolemia, both as primary and secondary prevention. Besides the lipid-lowering effect, statins have been suggested to inhibit the development of cardiovascular disease through anti-inflammatory, antioxidant, vascular endothelial function-improving, plaque-stabilizing, and platelet aggregation-inhibiting effects. The preventive effect of statins on atherothrombotic stroke has been well established, but statins can influence other cerebrovascular diseases. This suggests that statins have many neuroprotective effects in addition to lowering cholesterol. Furthermore, research suggests that statins cause pro-apoptotic, growth-inhibitory, and pro-differentiation effects in various malignancies. Preclinical and clinical evidence suggests that statins inhibit tumor growth and induce apoptosis in specific cancer cell types. The pleiotropic effects of statins on cardiovascular and cerebrovascular diseases have been well established; however, the effects of statins on cancer patients have not been fully elucidated and are still controversial. This review discusses the recent evidence on the effects of statins on cardiovascular and cerebrovascular diseases and cancer. Additionally, this study describes the pharmacological action of statins, focusing on the aspect of ‘beyond lipid-lowering’.

2021 ACC/AHA/SCAI Guideline for Coronary Artery Revascularization: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The guideline for coronary artery revascularization replaces the 2011 coronary artery bypass graft surgery and the 2011 and 2015 percutaneous coronary intervention guidelines, providing a patient-centric approach to guide clinicians in the treatment of patients with significant coronary artery disease undergoing coronary revascularization as well as the supporting documentation to encourage their use.

METHODS

A comprehensive literature search was conducted from May 2019 to September 2019, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Collaboration, CINHL Complete, and other relevant databases. Additional relevant studies, published through May 2021, were also considered.

STRUCTURE

Coronary artery disease remains a leading cause of morbidity and mortality globally. Coronary revascularization is an important therapeutic option when managing patients with coronary artery disease. The 2021 coronary artery revascularization guideline provides recommendations based on contemporary evidence for the treatment of these patients. The recommendations present an evidence-based approach to managing patients with coronary artery disease who are being considered for coronary revascularization, with the intent to improve quality of care and align with patients' interests.

Regulation of Long Non-Coding RNAs by Statins in Atherosclerosis

Despite increased public health awareness, atherosclerosis remains a leading cause of mortality worldwide. Significant variations in response to statin treatment have been noted among different populations suggesting that the efficacy of statins may be altered by both genetic and environmental factors. The existing literature suggests that certain long noncoding RNAs (lncRNAs) might be up- or downregulated among patients with atherosclerosis. LncRNA may act on multiple levels (cholesterol homeostasis, vascular inflammation, and plaque destabilization) and exert atheroprotective or atherogenic effects. To date, only a few studies have investigated the interplay between statins and lncRNAs known to be implicated in atherosclerosis. The current review characterizes the role of lncRNAs in atherosclerosis and summarizes the available evidence related to the effect of statins in regulating lncRNAs.

Beneficial Effect of Statin Therapy on Arterial Stiffness

Arterial stiffness describes the increased rigidity of the arterial wall that occurs as a consequence of biological aging and several diseases. Numerous studies have demonstrated that parameters to assess arterial stiffness, especially pulse-wave velocity, are predictive of those individuals that will suffer cardiovascular morbidity and mortality. Statin therapy may be a pharmacological strategy to improve arterial elasticity. It has been shown that the positive benefits of statin therapy on cardiovascular disease is attributable not only to their lipid-lowering capacity but also to various pleiotropic effects, such as their anti-inflammatory, antiproliferative, antioxidant, and antithrombotic properties. Additionally, statins reduce endothelial dysfunction, improve vascular and myocardial remodeling, and stabilize atherosclerotic plaque. The aim of the present review was to summarize the evidence from human studies showing the effects of statins on arterial stiffness.

High-Dose Atorvastatin Raises Threshold of Contrast-Induced Nephropathy in Diabetic Patients Undergoing Elective Coronary Intervention: A Randomized Controlled Study

Background. Contrast-induced nephropathy (CIN) is a significant complication of angiographic procedures resulting from injection of iodinated contrast media (CM). Patients with diabetes mellitus (DM) are at the highest risk of CIN. Statins have recently been proposed for protection against CIN due to their antioxidant and anti-inflammatory properties. Aim of Work. To investigate the potential benefit of acute pretreatment with high-dose atorvastatin (80 mg) in reduction of the incidence of CIN in diabetic patients indicated for elective coronary intervention. Patients and Methods. 200 diabetic patients with indication for coronary intervention were enrolled in the study. 100 patients will be randomly assigned to receive atorvastatin (80 mg) just before coronary intervention (statin group) and 100 patients received placebo (control group). CIN was defined as a rise of serum creatinine of more than 25% or ≥0.5 mg/dl (44 μmol/l) from baseline within 48 hours of the angiography. After the procedure, Thrombolysis in Myocardial Infarction (TIMI) flow of the culprit vessel was reported, as well as the volume of used contrast media and time of X-ray exposure. Results. Our study reported a CIN incidence of 12, 18, and 6% among the whole study, placebo, and statin groups, respectively, $P$ value of 0.001. Among the placebo group, CIN is likely to develop after a 13.5-minute X-ray exposure time with a specificity of 73.2% and sensitivity of 77.8%, area under the curve (AUC) of 0.879 (CI: 0.798–0.960), and $P$ value of 0.001, while in the statin group, CIN is likely to develop after 14.5-minute X-ray exposure time with a specificity of 74.5% and sensitivity of 83.3%, AUC of 0.818 (CI: 0.727–0.910), and P value of 0.009. In the placebo group, CIN is likely to develop after injection of 145 ml of contrast media with a specificity of 75.6% and sensitivity of 77.8%, AUC of 0.855 (CI: 0.757–0.952), and $P$ value of 0.001, while in the statin group, CIN is likely to develop after injection of 165 ml of contrast media with a specificity of 84% and sensitivity of 83.3%, AUC of 0.878 (CI: 0.811–0.944), and $P$ value of 0.002. Conclusions. Acute pretreatment with high-dose atorvastatin can effectively protect against CIN and was associated with a marked decrease in the prevalence of CIN in diabetic patients undergoing coronary interventions. Moreover, pretreatment with high-dose atorvastatin raises the threshold of X-ray exposure time and the amount of contrast media beyond which CIN is likely to develop. The trial is registered with NCT04375787.

Pravastatin-induced changes in expression of long non-coding and coding RNAs in endothelial cells

OBJECTIVE

Atherosclerosis is the main cause of the cardiovascular disease (CVD). Elevated blood cholesterol and inflammation of the endothelium are two major mechanisms contributing to the establishment of atherosclerotic plaques. Statins, such as pravastatin, are blood-cholesterol lowering drugs commonly prescribed for patients with or at risk for CVDs. In addition to lowering blood cholesterols, statins have recently been shown to improve endothelial function in both hyper- and normocholesterolemic patients with atherosclerosis. To understand the molecular mechanisms underlying the endothelial function improvement by statins, we assessed the RNA profile of pravastatin-treated endothelial cells, particularly their mRNAs and long non-coding RNAs (lncRNAs).

METHODS

Human umbilical vein endothelial cells (HUVECs) treated with pravastatin (10 µM) for 24 hr were profiled for lncRNAs and mRNAs using the Arraystar Human lncRNA Expression Microarray V3.0.

RESULTS

Of the 30,584 different lncRNAs screened, 95 were significantly upregulated, while 86 were downregulated in HUVECs responding to pravastatin. LINC00281 and BC045663 were the most upregulated (~8-fold) and downregulated (~3.5-fold) lncRNAs, respectively. Of the 26,106 different mRNAs screened in the pravastatin-treated HUVEC samples, 190 were significantly upregulated, while 90 were downregulated. Assigning the differentially expressed genes by bioinformatics into functional groups revealed their molecular signaling involvement in the following physiological processes: osteoclast differentiation, Rap1 signaling pathway, hematopoiesis, immunity, and neurotrophin signaling pathway.

CONCLUSIONS

This is the first lncRNA and mRNA expression profiling of pravastatin-mediated changes in human endothelial cells. Our results reveal potential novel targets and mechanisms for pravastatin-mediated vascular protection in atherosclerosis.

Hyperlipidemia does not affect development of elastase-induced abdominal aortic aneurysm in mice

BACKGROUND AND AIMS

Hyperlipidemia is a suggested risk factor for abdominal aortic aneurysm (AAA). However, whether hyperlipidemia is causally involved in AAA progression remains elusive. Here, we tested the hypothesis that hyperlipidemia aggravates AAA formation in the widely used porcine pancreatic elastase (PPE) model of AAA in mice with varying levels of plasma lipids.

METHODS

Prior to PPE-surgery, 8-week-old male C57BL/6J mice (n = 32) received 1·10¹¹ viral genomes of rAAV8-D377Y-mPcsk9 or control rAAV8 via the tail vein. Mice were fed either western type diet or regular chow. At baseline and during the 28 days following PPE-surgery, mice underwent weekly ultrasonic assessment of AAA progression. Experiments were repeated using Apolipoprotein E knockout (ApoE^-/-) mice (n = 7) and wildtype C57BL/6J mice (n = 5).

RESULTS

At sacrifice, maximal intergroup plasma cholesterol and non-HDL/HDL ratio differences were >5-fold and >20-fold, respectively. AAA diameters expanded to 150% of baseline, but no intergroup differences were detected. This was verified in an independent experiment comparing 8-week-old male ApoE^-/- mice with wildtype mice. Histological evaluation of experimental AAA lesions revealed accumulated lipid in neointimal and medial layers, and analysis of human AAA lesions (n = 5) obtained from open repair showed medial lipid deposition.

CONCLUSIONS

In summary, we find that lipid deposition in the aortic wall is a feature of PPE-induced AAA in mice as well as human AAA lesions. Despite, our data do not support the hypothesis that hyperlipidemia contributes to AAA progression.

Effect of 12-month intervention with low-dose atorvastatin on pulse wave velocity in subjects with type 2 diabetes and dyslipidaemia

Cardiovascular disease is the leading cause of morbidity and mortality in subjects with type 2 diabetes mellitus. Increased aortic stiffness, assessed with the carotid-femoral pulse wave velocity, is an independent risk factor for cardiovascular disease. Statins reduce effectively cardiovascular disease and mortality in high-risk patients. The aim of this prospective non-randomized, observational study was to examine the impact of treatment with either 10 mg atorvastatin plus diet or diet alone on carotid-femoral pulse wave velocity in subjects with type 2 diabetes mellitus and dyslipidaemia. A total of 79 subjects with type 2 diabetes mellitus and dyslipidaemia were included; 46 subjects were treated with atorvastatin 10 mg daily plus diet and 33 were managed by diet alone for 12 months. Carotid-femoral pulse wave velocity and carotid-radial pulse wave velocity were measured using applanation tonometry. In the atorvastatin-treated group, carotid-femoral pulse wave velocity reduced significantly during the study and there was a trend for reduction in the carotid-radial pulse wave velocity. Total cholesterol, low-density lipoprotein cholesterol, triglycerides and C-reactive protein were reduced only in the atorvastatin-treated participants. No significant changes were found in body mass index, blood pressure, heart rate, diabetes control and high-density lipoprotein cholesterol in either study group. Treatment with low-dose atorvastatin for 12 months improves carotid-femoral pulse wave velocity in subjects with type 2 diabetes mellitus and dyslipidaemia.

Efficacy of atorvastatin on the prevention of contrast-induced acute kidney injury: a meta-analysis

Background

Results of studies on the efficacy of atorvastatin pretreatment on reducing the prevalence of contrast-induced acute kidney injury (CIAKI) in patients undergoing coronary angiography (CAG) or percutaneous coronary intervention (PCI) have been controversial.

Objective

We undertook a meta-analysis to evaluate the efficacy of atorvastatin on contrast-induced nephropathy (CIN) after CAG or PCI.

Materials and methods

We undertook a systematic search of electronic databases (PubMed, Embase, and the Cochrane Library) up to June 2017. A meta-analysis was carried out including randomized controlled trials (RCTs) that compared atorvastatin pretreatment with pretreatment with a low-dose statin or placebo for CIAKI prevention in patients undergoing CAG. The main endpoint was CIN prevalence.

Results

Nine RCTs were included in our meta-analysis. Atorvastatin pretreatment reduced the prevalence of CIN significantly (odds ratio [OR] 0.46; 95% confidence interval [95% CI] 0.27–0.79; p=0.004). The benefit of high-dose atorvastatin pretreatment was consistent when compared with the control group (OR 0.45; 95% CI 0.21–0.95; p=0.04).

Conclusion

At high doses, atorvastatin pretreatment was associated with a significant reduction in the prevalence of CIAKI in patients undergoing CAG. Pretreatment with high-dose atorvastatin could be employed to prevent CIAKI.

Effect of statin therapy on pulse wave velocity: A meta-analysis of randomized controlled trials

BACKGROUND AND OBJECTIVE

Arterial stiffness (AS) is an independent cardiovascular risk factor. A number of studies have reported a beneficial role of statins on AS albeit with controversial results, in addition to their effects on lipid profile. Therefore, we carried out a meta-analysis of the available randomized controlled trials assessing the effects of statin therapy on AS, in the attempt to reach more definitive conclusions.

METHODS

A systematic search of the on-line databases available up to March 2017 was conducted, including intervention studies reporting AS expressed by carotid-femoral pulse wave velocity (PWV), as difference between the effects of treatment with or without statins. For each study, mean difference (MD) and 95% confidence intervals (CI) were pooled using a random effect model.

RESULTS

Eleven studies met the pre-defined inclusion criteria, for a total of 573 participants and 2-144 weeks' intervention time. In the pooled analysis, statin therapy was associated with a -6.8% (95% C.I.: -11.7 to -1.8) reduction in PWV. There was significant heterogeneity among studies (I² = 96%); none of the study characteristics seems to have influenced the effect of statin use on PWV.

CONCLUSIONS

The results of this meta-analysis suggest that statin therapy reduces AS. This effect appears to be at least in part independent of the changes in blood pressure and lipid profile.

Statin therapy exacerbates alcohol-induced constriction of cerebral arteries via modulation of ethanol-induced BK channel inhibition in vascular smooth muscle

Statins constitute the most commonly prescribed drugs to decrease cholesterol (CLR). CLR is an important modulator of alcohol-induced cerebral artery constriction (AICAC). Using rats on a high CLR diet (2% CLR) we set to determine whether atorvastatin administration (10mg/kg daily for 18-23weeks) modified AICAC. Middle cerebral arteries were pressurized in vitro at 60mmHg and AICAC was evoked by 50mM ethanol, that is within the range of blood alcohol detected in humans following moderate-to-heavy drinking. AICAC was evident in high CLR+atorvastatin group but not in high CLR diet+placebo. Statin exacerbation of AICAC persisted in de-endothelialized arteries, and was blunted by CLR enrichment in vitro. Fluorescence imaging of filipin-stained arteries showed that atorvastatin decreased vascular smooth muscle (VSM) CLR when compared to placebo, this difference being reduced by CLR enrichment in vitro. Voltage- and calcium-gated potassium channels of large conductance (BK) are known VSM targets of ethanol, with their beta1 subunit being necessary for ethanol-induced channel inhibition and resulting AICAC. Ethanol-induced BK inhibition in excised membrane patches from freshly isolated myocytes was exacerbated in the high CLR diet+atorvastatin group when compared to high CLR diet+placebo. Unexpectedly, atorvastatin decreased the amount and function of BK beta1 subunit as documented by immunofluorescence imaging and functional patch-clamp studies. Atorvastatin exacerbation of ethanol-induced BK inhibition disappeared upon artery CLR enrichment in vitro. Our study demonstrates for the first time statin's ability to exacerbate the vascular effect of a widely consumed drug of abuse, this exacerbation being driven by statin modulation of ethanol-induced BK channel inhibition in the VSM via CLR-mediated mechanism.

Cytokines and MicroRNA in Coronary Artery Disease

Cardiovascular disease (CVD) is a major health problem globally. The high incidence and case fatality of CVD are, to a large extent, a consequence of its late diagnosis and lack of highly sensitive and specific markers. Only a very small number of biomarkers, such as troponin, detect late disease. There is some evidence of an association and dysregulation between specific cytokines in the pathogenesis of CVD. These molecules are involved in inflammatory and immune mechanisms associated with atherogenesis. Several molecular/cellular pathways that include STAT, MAPK, and SMAD are modulated by cytokines. Against this background, microRNAs (miRNAs) are a class of noncoding RNAs with important roles in pathological events, leading to atherosclerotic CVD. It has been shown that the latter could affect cytokine production and contribute to progression of atherosclerotic CVD. Moreover, modulation of miRNAs appears to inhibit cardiomyocyte apoptosis, attenuate infarct size, and reduce cardiac dysfunction. This review highlights several recent preclinical and clinical studies on the role of cytokines in CVD, novel miRNA-based therapeutic approaches for therapeutic intervention, and potential circulating cytokines that have promise as biomarkers in CVD.

Effects of Atorvastatin Dose and Concomitant Use of Angiotensin-Converting Enzyme Inhibitors on Renal Function Changes over Time in Patients with Stable Coronary Artery Disease: A Prospective Observational Study

Angiotensin-converting enzyme inhibitors (ACEI) and statins are widely used in patients with coronary artery disease (CAD). Our aim was to compare changes in glomerular filtration rate (GFR) over time in subjects with stable CAD according to atorvastatin dose and concomitant use of ACEI. We studied 78 men with stable CAD referred for an elective coronary angiography who attained the then-current guideline-recommended target level of low-density lipoproteins (LDL) cholesterol below 2.5 mmol/L in a routine fasting lipid panel on admission and were receiving atorvastatin at a daily dose of 10-40 mg for ≥3 months preceding the index hospitalization. Due to an observational study design, atorvastatin dosage was not intentionally modified for other reasons. GFR was estimated during index hospitalization and at about one year after discharge from our center. Irrespective of ACEI use, a prevention of kidney function loss was observed only in those treated with the highest atorvastatin dose. In 38 subjects on ACEI, both of the higher atorvastatin doses were associated with increasing beneficial effects on GFR changes (mean ± SEM: -4.2 ± 2.4, 1.1 ± 1.6, 5.2 ± 2.4 mL/min per 1.73 m² for the 10-mg, 20-mg and 40-mg atorvastatin group, respectively, p = 0.02 by ANOVA; Spearman's rho = 0.50, p = 0.001 for trend). In sharp contrast, in 40 patients without ACEI, no significant trend effect was observed across increasing atorvastatin dosage (respective GFR changes: -1.3 ± 1.0, -4.7 ± 2.1, 4.8 ± 3.6 mL/min per 1.73 m², p = 0.02 by ANOVA; rho = 0.08, p = 0.6 for trend). The results were substantially unchanged after adjustment for baseline GFR or time-dependent variations of LDL cholesterol. Thus, concomitant ACEI use appears to facilitate the ability of increasing atorvastatin doses to beneficially modulate time-dependent changes in GFR in men with stable CAD.

Short-term rosuvastatin treatment for the prevention of contrast-induced acute kidney injury in patients receiving moderate or high volumes of contrast media: a sub-analysis of the TRACK-D study

BACKGROUND

Current randomized trials have demonstrated the effects of short-term rosuvastatin therapy in preventing contrast-induced acute kidney injury (CIAKI). However, the consistency of these effects on patients administered different volumes of contrast media is unknown.

METHODS

In the TRACK-D trial, 2998 patients with type 2 diabetes and concomitant chronic kidney disease (CKD) who underwent coronary/peripheral arterial angiography with or without percutaneous intervention were randomized to short-term (2 days before and 3 days after procedure) rosuvastatin therapy or standard-of-care. This prespecified analysis compared the effects of rosuvastatin versus standard therapy in patients exposed to (moderate contrast volume [MCV], 200-300 ml, n = 712) or (high contrast volume [HCV], ≥ 300 ml, n = 220). The primary outcome was the incidence of CIAKI. The secondary outcome was a composite of death, dialysis/hemofiltration or worsened heart failure at 30 days.

RESULTS

Rosuvastatin treatment was associated with a significant reduction in CIAKI compared with the controls (2.1% vs. 4.4%, P = 0.050) in the overall cohort and in patients with MCV (1.7% vs. 4.5%, P = 0.029), whereas no benefit was observed in patients with HCV (3.4% vs. 3.9%, P = 0.834). The incidence of secondary outcomes was significantly lower in the rosuvastatin group compared with control group (2.7% vs. 5.3%, P = 0.049) in the overall cohort, but it was similar between the patients with MCV (2.0% vs. 4.2%, P = 0.081) or HCV (5.1% vs. 8.8%, P = 0.273).

CONCLUSIONS

Periprocedural short-term rosuvastatin treatment is effective in reducing CIAKI and adverse clinical events for patients with diabetes and CKD after their exposure to a moderate volume of contrast medium.

The role of statins in the prevention of contrast induced nephropathy: a meta-analysis of 8 randomized trials

Contrast induced nephropathy (CIN) is a common complication of coronary angiography/angioplasty. Prevention is the key to reduce the incidence of CIN and it begins with appropriate pre-procedural management. Statins have been shown to possess pleiotropic effects (anti-oxidant, anti-inflammatory and anti-thrombotic properties) and their effects on CIN were assessed in several studies with conflicting results. Aim of this meta-analysis is to evaluate the efficacy of short-term statins for the prevention of CIN in patients undergoing coronary angiography/percutaneous interventions. We performed formal searches of PubMed, EMBASE, Cochrane central register of controlled trials and major international scientific session abstracts from January 1990 to January 2014 of trials which compares short-term statins versus Placebo for the prevention of CIN in patients undergoing coronary angiography/angioplasty. Data regarding study design, statin dose, inclusion/exclusion criteria, number of patients, and clinical outcome was extracted by 2 investigators. Eight trials were included, with a total of 4734 patients. CIN occurred in 79/2,358 patients (3.3%) treated with statins versus 153/2,376 patients (6.4%) of the placebo group [OR 95% CI 0.50 (0.38-0.66), p < 0.00001; p het = 0.39]. Benefits were both observed with high-dose short-term statins [OR 95% CI 0.44 (0.30-0.65), p < 0.0001; p het = 0.16] and low-dose statins, [OR 95% CI 0.58 (0.39-0.88), p = 0.010; p het = 0.90]. By meta-regression analysis, no significant relationship was observed between benefits from statin therapy and patient's risk profile (p = 0.26), LDL cholesterol (p = 0.4), contrast volume (p = 0.94) or diabetes rate (p = 0.38). This meta-analysis showed that among patients undergoing coronary angiography/percutaneous intervention the use of short-term statins reduces the incidence of CIN, and therefore is highly recommended even in patients with low LDL-cholesterol levels.

A meta-analysis of randomized controlled trials on statins for the prevention of contrast-induced acute kidney injury in patients with and without acute coronary syndromes

OBJECTIVES

We assessed whether short-term, pre-procedural, intensive statin treatment may reduce contrast-induced acute kidney injury (CI-AKI) incidence in patients with and without acute coronary syndromes (ACS) undergoing coronary angiography (CA) and percutaneous coronary intervention (PCI).

BACKGROUND

Statins may exert renal-protective effects through their pleiotropic properties. However, there have been conflicting reports on the CI-AKI preventive effect of pre-procedural statin administration.

METHODS

Randomized controlled trials published between January 1st, 2003 and February 28th, 2014 comparing the preventive effects against CI-AKI of pre-procedural statins vs. control (lower statin dose, no statin, or placebo) in patients undergoing CA/PCI were included.

RESULTS

Data were combined from 9 clinical trials enrolling 5212 patients (age 65 ± 5 years, 63% males). Pooled analysis showed that intensive, short-term statin pre-treatment significantly reduced the risk of CI-AKI as compared to control (relative risk [RR] 0.50; 95% confidence interval [CI] 0.39 to 0.64; P<0.001). Pre-specified subgroup analysis showed that intensive statin pre-treatment significantly reduced CI-AKI risk in patients with ACS (RR 0.37; 95% CI 0.25 to 0.55; P<0.0001), with only a non-significant positive trend in patients without ACS (RR 0.65; 95% CI 0.41 to 1.03; P=0.07). No evidence of publication bias was detected.

CONCLUSIONS

Short-term, pre-procedural, intensive statin treatment significantly reduced CI-AKI incidence in ACS patients, and may contribute to the overall clinical benefit associated with the early use of these drugs in this clinical setting. Its role in non-ACS patients warrants further investigation.

The many roles of statins in ischemic stroke

Stroke is the third leading cause of human death. Endothelial dysfunction, thrombogenesis, inflammatory and oxidative stress damage, and angiogenesis play an important role in cerebral ischemic pathogenesis and represent a target for prevention and treatment. Statins have been found to improve endothelial function, modulate thrombogenesis, attenuate inflammatory and oxidative stress damage, and facilitate angiogenesis far beyond lowering cholesterol levels. Statins have also been proved to significantly decrease cardiovascular risk and to improve clinical outcome. Could statins be the new candidate agent for the prevention and therapy in ischemic stroke? In recent years, a vast expansion in the understanding of the pathophysiology of ischemic stroke and the pleiotropic effects of statins has occurred and clinical trials involving statins for the prevention and treatment of ischemic stroke have begun. These facts force us to revisit ischemic stroke and consider new strategies for prevention and treatment. Here, we survey the important developments in the non-lipid dependent pleiotropic effects and clinical effects of statins in ischemic stroke.

Efficacy of short-term high-dose statin pretreatment in prevention of contrast-induced acute kidney injury: updated study-level meta-analysis of 13 randomized controlled trials

BACKGROUND

There have been conflicting results across the trials that evaluated prophylactic efficacy of short-term high-dose statin pre-treatment for prevention of contrast-induced acute kidney injury (CIAKI) in patients undergoing coronary angiography (CAG). The aim of the study was to perform an up-to-date meta-analysis regarding the efficacy of high-dose statin pre-treatment in preventing CIAKI.

METHODS AND RESULTS

Randomized-controlled trials comparing high-dose statin versus low-dose statin or placebo pre-treatment for prevention of CIAKI in patients undergoing CAG were included. The primary endpoint was the incidence of CIAKI within 2-5 days after CAG. The relative risk (RR) with 95% CI was the effect measure. This analysis included 13 RCTs with 5,825 total patients; about half of them (n = 2,889) were pre-treated with high-dose statin (at least 40 mg of atorvastatin) before CAG, and the remainders (n = 2,936) pretreated with low-dose statin or placebo. In random-effects model, high-dose statin pre-treatment significantly reduced the incidence of CIAKI (RR 0.45, 95% CI 0.35-0.57, p<0.001, I(2)= 8.2%, NNT 16), compared with low-dose statin or placebo. The benefit of high-dose statin was consistent in both comparisons with low-dose statin (RR 0.47, 95% CI 0.34-0.65, p<0.001, I(2) = 28.4%, NNT 19) or placebo (RR 0.34, 95% CI 0.21-0.58, p<0.001, I(2)= 0.0%, NNT 16). In addition, high-dose statin showed significant reduction of CIAKI across various subgroups of chronic kidney disease, acute coronary syndrome, and old age (≥ 60 years), regardless of osmolality of contrast or administration of N-acetylcystein.

CONCLUSIONS

High-dose statin pre-treatment significantly reduced overall incidence of CIAKI in patients undergoing CAG, and emerges as an effective prophylactic measure to prevent CIAKI.

Statins and contrast-induced acute kidney injury with coronary angiography

BACKGROUND

Contrast-induced acute kidney injury is an adverse outcome resulting from radiocontrast medium exposure during coronary angiography and percutaneous coronary intervention.

METHODS

A systematic search was conducted to retrieve studies that investigated the impact of statin exposure before coronary angiography or percutaneous coronary intervention on the development of contrast-induced acute kidney injury. The primary outcome was the development of contrast-induced acute kidney injury. We separately analyzed statin/placebo comparisons and high-/low-dose statin comparisons.

RESULTS

Fifteen randomized controlled trials met inclusion criteria: 11 studies with statin-naïve subjects, 2 studies with chronic statin users, and 2 studies with unspecified prior statin exposure. Statin exposure reduced the risk of contrast-induced acute kidney injury relative to placebo (relative risk [RR] 0.63, P = .01) with a nonsignificant reduction in the need for hemodialysis (RR 0.25, P = .08). This benefit was also observed in high-dose versus low-dose statin trials (RR 0.46, P = .004), in statin-naïve patients (RR 0.53, P <.0001), and with all studied statins. Higher statin exposure reduced contrast-induced acute kidney injury in patients with acute coronary syndromes compared with placebo or low-dose statins (RR 0.49, P <.00001), with no significant benefit among patients undergoing elective procedures (RR 0.86, P = .50). Subgroup analyses confirmed the benefit of statins in patients with diabetes, chronic kidney disease, congestive heart failure, and those receiving >140 mL of contrast dye.

CONCLUSION

Statin therapy is effective at reducing the risk of contrast-induced acute kidney injury. It should thus be considered, at least on a short-term basis, for patients at increased risk of this complication.

Statins for the Prevention of Contrast-Induced Nephropathy After Coronary Angiography/Percutaneous Interventions: A Meta-analysis of Randomized Controlled Trials

BACKGROUND

Statins have been demonstrated to prevent the development of contrast-induced nephropathy (CIN). Nevertheless, clinical research has indicated conflicting results. We performed a meta-analysis of randomized controlled trials (RCTs) to evaluate the protective effects of statins on CIN and the requirement of renal replacement therapy (RRT) in patients undergoing coronary angiography/percutaneous interventions.

METHODS

PubMed, MEDLINE, Web of Science, EMBASE, ClinicalTrials.gov, and the Cochrane Central RCTs were searched for RCTs from inception to February 2014 to compare statins with placebo treatment for preventing CIN in patients undergoing coronary angiography/percutaneous interventions.

RESULTS

Nine RCTs were identified and analyzed in a total of 5143 patients involving 2560 patients with statin pretreatment and 2583 patients as control. Patients who received statin therapy had a 53% lower risk of CIN with different definitions (within 48 or 72 hours) compared to the control group based on a fixed effect model (risk ratio = 0.47, 95% confidence interval = 0.37-0.60, P < .0001) and were less likely to require RRT based on Peto fixed effect. Subgroup analysis showed that statin pretreatment could decrease the incidence of CIN in patients with preexisting renal dysfunction or diabetes mellitus. In addition, patients on rosuvastatin had a similar reduced incidence of CIN compared to patients on atorvastatin.

CONCLUSION

This updated meta-analysis demonstrated that preprocedural statin treatment could reduce the risk of CIN and the need for RRT in patients undergoing coronary angiography/percutaneous interventions. Moreover, statin therapy would be helpful in reducing the incidence of CIN in high-risk patients with preexisting renal dysfunction or diabetes mellitus. Additionally, rosuvastatin and atorvastatin had similar efficacies in preventing CIN development.

The Role of Statins in Preventing Contrast-Induced Acute Kidney Injury

The incidence of contrast-induced acute kidney injury (CI-AKI) is rising due to increased use of coronary angiography and percutaneous coronary intervention. Many agents, including statins, have been evaluated in several studies for the prevention of CI-AKI. To date, there have been 14 prospective randomized studies regarding the efficacy of statins on the patient. Most of these studies and 3 recent meta-analyses have concluded that statins should be used for this purpose, even in patients with reduced low-density lipoprotein cholesterol levels. However, there are also conflicting results, most likely due to marked heterogeneity of patient characteristics, dosage and administration patterns of statins, definition of CI-AKI, and different statistical analyses. In conclusion, it is uncertain whether statins should be prescribed to prevent CI-AKI in the absence of other indications.

Statins in chronic kidney disease and kidney transplantation

HMG-CoA reductase inhibitors (statins) have been shown to improve cardiovascular (CV) outcomes in the general population as well as in patients with cardiovascular disease (CVD). Statins' beneficial effects have been attributed to both cholesterol-lowering and cholesterol-independent "pleiotropic" properties. By their pleiotropic effects statins have been shown to reduce inflammation, alleviate oxidative stress, modify the immunologic responses, improve endothelial function and suppress platelet aggregation. Patients with chronic kidney disease (CKD) exhibit an enormous increase in CVD rates even from early CKD stages. As considerable differences exist in dyslipidemia characteristics and the pathogenesis of CVD in CKD, statins' CV benefits in CKD patients (including those with a kidney graft) should not be considered unequivocal. Indeed, accumulating clinical evidence suggests that statins exert diverse effects on dialysis and non-dialysis CKD patients. Therefore, it seems that statins improve CV outcomes in non-dialysis patients whereas exert little (if any) benefit in the dialysis population. It has also been proposed that dyslipidemia might play a causative role or even accelerate renal injury. Moreover, ample experimental evidence suggests that statins ameliorate renal damage. However, a high quality randomized controlled trial (RCT) and metaanalyses do not support a beneficial role of statins in renal outcomes in terms of proteinuria reduction or retardation of glomerular filtration rate (GFR) decline.

The incidence of kidney injury for patients treated with a high-potency versus moderate-potency statin regimen after an acute coronary syndrome

BACKGROUND

Observational studies have raised concerns that high-potency statins increase the risk of acute kidney injury. We therefore examined the incidence of kidney injury across 2 randomized trials of statin therapy.

METHODS AND RESULTS

PROVE IT-TIMI 22 enrolled 4162 subjects after an acute coronary syndrome (ACS) and randomized them to atorvastatin 80 mg/day versus pravastatin 40 mg/day. A-to-Z enrolled 4497 subjects after ACS and randomized them to a high-potency (simvastatin 40 mg/day × 1 months, then simvastatin 80 mg/day) versus a delayed moderate-potency statin strategy (placebo × 4 months, then simvastatin 20 mg/day). Serum creatinine was assessed centrally at serial time points. Adverse events (AEs) relating to kidney injury were identified through database review. Across both trials, mean serum creatinine was similar between treatment arms at baseline and throughout follow-up. In A-to-Z, the incidence of a 1.5-fold or ≥ 0.3 mg/dL rise in serum creatinine was 11.4% for subjects randomized to a high-potency statin regimen versus 12.4% for those on a delayed moderate-potency regimen (odds ratio [OR], 0.91; 95% confidence interval [CI], 0.76 to 1.10; P=0.33). In PROVE IT-TIMI 22, the incidence was 9.4% for subjects randomized to atorvastatin 80 mg/day and 10.6% for subjects randomized to pravastatin 40 mg/day (OR, 0.88; 95% CI, 0.71 to 1.09; P=0.25). Consistent results were observed for different kidney injury thresholds and in individuals with diabetes mellitus or with moderate renal dysfunction. The incidence of kidney injury-related adverse events (AEs) was not statistically different for patients on a high-potency versus moderate-potency statin regimen (OR, 1.06; 95% CI, 0.68 to 1.67; P=0.78).

CONCLUSIONS

For patients enrolled in 2 large randomized trials of statin therapy after ACS, the use of a high-potency statin regimen did not increase the risk of kidney injury.

Statins and the autonomic nervous system

Statins (3-hydroxy-3-methylglutaryl-CoA reductase inhibitors) reduce plasma cholesterol and improve endothelium-dependent vasodilation, inflammation and oxidative stress. A ‘pleiotropic’ property of statins receiving less attention is their effect on the autonomic nervous system. Increased central sympathetic outflow and diminished cardiac vagal tone are disturbances characteristic of a range of cardiovascular conditions for which statins are now prescribed routinely to reduce cardiovascular events: following myocardial infarction, and in hypertension, chronic kidney disease, heart failure and diabetes. The purpose of the present review is to synthesize contemporary evidence that statins can improve autonomic circulatory regulation. In experimental preparations, high-dose lipophilic statins have been shown to reduce adrenergic outflow by attenuating oxidative stress in central brain regions involved in sympathetic and parasympathetic discharge induction and modulation. In patients with hypertension, chronic kidney disease and heart failure, lipophilic statins, such as simvastatin or atorvastatin, have been shown to reduce MNSA (muscle sympathetic nerve activity) by 12–30%. Reports concerning the effect of statin therapy on HRV (heart rate variability) are less consistent. Because of their implications for BP (blood pressure) control, insulin sensitivity, arrhythmogenesis and sudden cardiac death, these autonomic nervous system actions should be considered additional mechanisms by which statins lower cardiovascular risk.

Effects of low-dose atorvastatin on arterial stiffness and central aortic pressure augmentation in patients with hypertension and hypercholesterolemia

BACKGROUND

Experimental and clinical data suggest that statins exert anti-inflammatory and antiproliferative actions on vasculature beyond their lipid-lowering properties. Whether these pleiotropic effects of statins translate into a beneficial effect on arterial stiffness is not clear. This study aimed to evaluate the potential effects of low-dose atorvastatin treatment on arterial stiffness and central arterial pressure waveforms in patients with mild hypertension and hypercholesterolemia.

METHODS

In a double-blind, randomized, placebo-controlled fashion, 50 hypertensive and hypercholesterolemic patients were allocated to receive 10 mg of atorvastatin or placebo for 26 weeks. Arterial stiffness was assessed by aortic pulse-wave velocity (PWV) using a Sphygmocor device. Central arterial pressure waveform parameters were estimated by radial artery applanation tonometry. Heart rate-adjusted augmentation index (AIx(75)) was used as measure of wave reflections.

RESULTS

At study end, aortic PWV (9.0 ± 1.5 vs. 10.9 ± 2.6 m/sec; P < 0.001) and AIx(75) (24.9% ± 9.7% vs 28.8% ± 11.8%; P < 0.001) were significantly lower in the atorvastatin group than that placebo group. Furthermore, decreases in central aortic systolic blood pressure and pulse pressure were evident at study-end with atorvastatin but not with placebo (130 ± 8 vs. 138 ± 6 mm Hg, P < 0.001; 48 ± 7 vs. 53 ± 6 mm Hg, P < 0.05, respectively). Atorvastatin-induced reductions in aortic PWV during follow-up showed significant associations with changes in AIx(75) and central aortic systolic blood pressure and pulse pressure.

CONCLUSIONS

This study shows that low-dose atorvastatin treatment improves arterial stiffness and exerts a reduction on central aortic pressures. These effects may represent a potential mechanism of cardiovascular risk reduction observed with statin use.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov Database Identifier Number: NCT01126684.

Treatment With Low-dose Atorvastatin, Losartan, and Their Combination Increases Expression of Vasoactive-Related Genes in Rat Aortas

Recently it has been shown that statins and angiotensin receptor blockers (ARBs) at low doses express beneficial pleiotropic vascular effects. We aimed to explore whether these drugs at low doses induce the expression of vasoactive-related genes. Sixty adult Wistar rats were treated with low-dose atorvastatin (2 mg/kg), low-dose losartan (5 mg/kg), their combination or saline daily for 4, 6, or 8 weeks. Expression of the vasoactive-related genes endothelin receptor type A ( EDNRA), endothelial nitric oxide synthase 3 ( NOS3), inducible nitric oxide synthase 2 ( NOS2), and angiotensin II receptor type 1 ( AGTRL1a) was measured in isolated thoracic aortas. Expression of EDNRA gradually decreased, the lowest values being obtained after 8 weeks (low-dose atorvastatin, losartan [1.6- and 1-7-fold vs controls, respectively; both P < .05], and the combination [2.3-fold vs control, P < .001]). The highest values of NOS3 were obtained after 6 weeks (low-dose atorvastatin, losartan, and their combination, 3.1-fold, P < .01; 3.4-fold, P < .001; and 3.6-fold, P < .001 vs controls, respectively) and then declined after 8 weeks. The combination was more effective in inducing total NOS3 expression when compared to the separate drugs (1.4-fold; P < .05). Importantly, expression of NOS3 was associated with increased plasma NO levels and positively correlated with thoracic aorta relaxation. No changes in expression of NOS2 and AGTRL1a were observed. We showed that low-dose atorvastatin or losartan and especially their combination increases the expression of NOS3 and decreases the expression of EDNRA. These findings are valuable in explaining the effectiveness of the “low-dose pharmacological approach” for improvement in arterial function.

Efficacy of short-term high-dose statin in preventing contrast-induced nephropathy: a meta-analysis of seven randomized controlled trials

Background

A few studies focused on statin therapy as specific prophylactic measures of contrast-induced nephropathy have been published with conflicting results. In this meta-analysis of randomized controlled trials, we aimed to assess the effectiveness of shor-term high-dose statin treatment for the prevention of CIN and clinical outcomes and re-evaluate of the potential benefits of statin therapy.

Methods

We searched PubMed, OVID, EMBASE, Web of science and the Cochrane Central Register of Controlled Trials databases for randomized controlled trials comparing short-term high-dose statin treatment versus low-dose statin treatment or placebo for preventing CIN. Our outcome measures were the risk of CIN within 2–5 days after contrast administration and need for dialysis.

Results

Seven randomized controlled trials with a total of 1,399 patients were identified and analyzed. The overall results based on fixed-effect model showed that the use of short-term high-dose statin treatment was associated with a significant reduction in risk of CIN (RR = 0.51, 95% CI 0.34–0.76, p = 0.001; I² = 0%). The incidence of acute renal failure requiring dialysis was not significant different after the use of statin (RR = 0.33, 95% CI 0.05–2.10, p = 0.24; I² = 0%). The use of statin was not associated with a significant decrease in the plasma C-reactive protein level (SMD −0.64, 95% CI: −1.57 to 0.29, P = 0.18, I² = 97%).

Conclusions

Although this meta-analysis supports the use of statin to reduce the incidence of CIN, it must be considered in the context of variable patient demographics. Only a limited recommendation can be made in favour of the use of statin based on current data. Considering the limitations of included studies, a large, well designed trial that incorporates the evaluation of clinically relevant outcomes in participants with different underlying risks of CIN is required to more adequately assess the role for statin in CIN prevention.

Simvastatin reduces lipoprotein-associated phospholipase A2 in lipopolysaccharide-stimulated human monocyte-derived macrophages through inhibition of the mevalonate-geranylgeranyl pyrophosphate-RhoA-p38 mitogen-activated protein kinase pathway

Lipoprotein-associated phospholipase A(2) (Lp-PLA(2)), which is produced primarily by macrophages and is predominately found in the blood and in atherosclerotic plaques, represents a potentially promising target for combating atherosclerosis. Although statins are known to decrease the levels and activity of circulating and plaque Lp-PLA(2) during atherosclerosis, little is known regarding the mechanisms underlying inhibition of Lp-PLA(2) by statins. Therefore, the aim of this study was to explore the molecular mechanisms responsible for inhibition of Lp-PLA(2) by statins. Our results showed that treatment with simvastatin inhibited lipopolysaccharide (LPS)-induced increases in Lp-PLA(2) expression and secreted activity in human monocyte–derived macrophages in a dose- and time-dependent manner. These effects could be reversed by treatment with mevalonate or geranylgeranyl pyrophosphate (GGPP), but not by treatment with squalene or farnesyl pyrophosphate. Treatment with the Rho inhibitor C3 exoenzyme also inhibited LPS-induced increases in Lp-PLA(2) expression and secreted activity, mimicking the effects of simvastatin. In addition, treatment with simvastatin blocked LPS-induced activation of RhoA, which could be abolished by treatment with GGPP. Inhibition of p38 mitogen-activated protein kinase (MAPK), but not extracellular signal regulated kinase 1/2 or Jun N-terminal kinase, suppressed LPS-induced increases in Lp-PLA(2) expression and secreted activity, similar to the effects of simvastatin. Treatment of human monocyte–derived macrophages with either simvastatin or C3 exoenzyme prevented LPS-induced activation of p38 MAPK, which could be abolished by treatment with GGPP. Together, these results suggest that simvastatin reduces Lp-PLA(2) expression and secreted activity in LPS-stimulated human monocyte–derived macrophages through the inhibition of the mevalonate–GGPP–RhoA-p38 MAPK pathway. These observations provide novel evidence that statins have pleiotropic effects and suggest that inhibition of Lp-PLA(2) via this mechanism may account, at least in part, for the clinical benefit of statins in combating atherosclerosis.

Combination therapy with an angiotensin II receptor blocker and an HMG-CoA reductase inhibitor in experimental subtotal nephrectomy

BACKGROUND

Angiotensin receptor 1 blockers (ARB) are standard nephroprotective drugs in chronic kidney disease. There is less evidence for a nephroprotective effect of HMG-CoA reductase inhibitors (statins) and much less is known about potential benefits of combination therapy. We evaluated the therapeutic potential of a statin alone or in combination with an ARB in experimental chronic kidney disease.

METHODS

Subtotally nephrectomized (5/6 Nx) rats were treated early with vehicle, losartan, cerivastatin or losartan/cerivastatin. Expression of messenger RNA (mRNA) was assessed by real-time reverse transcription-polymerase chain reaction. Tissue proteins were localized by immunohistochemistry. Nuclear factor-κB (NF-κB) activation was measured in whole kidneys.

RESULTS

In contrast to the sham group, at 6 weeks, vehicle-treated 5/6 Nx rats displayed renal lesions, albuminuria and increased blood pressure, serum creatinine and total kidney NF-κB p65 DNA-binding activity and preproendothelin-1, fibronectin and type I and III collagen mRNA. NF-κB activation correlated with albuminuria and histological renal injury. Losartan or combination therapy preserved renal function, abrogated albuminuria and improved glomerular and interstitial histology. Cerivastatin alone preserved renal function and improved interstitial injury but did not influence albuminuria, glomerular histology or NF-κB activation. Losartan/cerivastatin normalized kidney NF-κB activation and extracellular matrix mRNA expression pattern. The effect of losartan alone on these parameters was less intense. All treatments decreased preproendothelin-1 mRNA and preserved interstitial capillaries.

CONCLUSIONS

In a chronic kidney disease model, early treatment with either an ARB or a statin preserved renal function although the mechanisms differed. Combination therapy with an ARB and a statin did not confer clear-cut advantages on biochemical and histological parameters over ARB alone, although it further improved the kidney NF-κB and gene expression profile.

Short-term effect of atorvastatin on carotid artery elasticity: a pilot study

BACKGROUND AND PURPOSE

Few studies have examined the early effects of statins on carotid artery elasticity, a potential surrogate marker of cardiovascular risk. This study examined the short-term effects of atorvastatin 80 mg daily on carotid elasticity measured by high-resolution B-mode ultrasound.

METHODS

The study included 40 stroke-free and statin-naive subjects older than age 45 (mean age, 70±7 years; 55% men; 64% Caribbean-Hispanic). Outcome measures included carotid stiffness indices at 14 and 30 days after initiation of treatment. The systolic and diastolic diameters of the right common carotid artery were averaged from multiple B-mode imaging frames. Absolute and relative changes of strain [(systolic diameter-diastolic diameter)/diastolic diameter], stiffness (β) [ln (systolic/diastolic blood pressure)/strain], and distensibility (1/β adjusted for wall thickness) from baseline were compared by the repeated measures t test and were considered significant at α=0.05.

RESULTS

Baseline mean stiffness was 0.08 (95% confidence interval [CI], 0.06-0.10). It significantly decreased at day 30 to 0.05 (CI, 0.04-0.06; P<0.01). Mean baseline distensibility was 15.25 (CI, 13.18-17.32), increasing significantly at day 30 to 17.23 (CI, 14.01-20.45; P<0.05). An improvement in distensibility of ≥10% from baseline was observed in 29 (73%) subjects. Changes in stiffness and distensibility were maximal among subjects with baseline low-density lipoprotein levels<130 mg/dL.

CONCLUSIONS

Short-term treatment with high-dose atorvastatin was associated with improvement in the carotid elasticity metrics. Carotid artery elasticity measured by B-mode ultrasound is a simple noninvasive measure of arterial wall function and may be a useful surrogate end point in clinical trials targeting individuals at increased risk for atherosclerosis.

Short-term, high-dose Atorvastatin pretreatment to prevent contrast-induced nephropathy in patients with acute coronary syndromes undergoing percutaneous coronary intervention (from the ARMYDA-CIN [atorvastatin for reduction of myocardial damage during angioplasty--contrast-induced nephropathy] trial

Contrast-induced nephropathy (CIN) impairs clinical outcome in patients undergoing angiographic procedures. The aim of this study was to investigate whether short-term high-dose atorvastatin load decreases the incidence of CIN after percutaneous coronary intervention (PCI). Statin-naive patients with acute coronary syndrome undergoing PCI (n = 241) randomly received atorvastatin (80 mg 12 hours before intervention with another 40-mg preprocedure dose, n = 120) or placebo (n = 121). All patients had long-term atorvastatin treatment thereafter (40 mg/day). Primary end point was incidence of CIN defined as postintervention increase in serum creatinine ≥0.5 mg/dl or >25% from baseline. Five percent of patients in the atorvastatin arm developed CIN versus 13.2% of those in the placebo arm (p = 0.046). In the atorvastatin group, postprocedure serum creatinine was significantly lower (1.06 ± 0.35 vs 1.12 ± 0.27 mg/dl in placebo, p = 0.01), creatinine clearance was decreased (80.1 ± 32.2 vs 72.0 ± 26.6 ml/min, p = 0.034), and C-reactive protein peak levels after intervention were decreased (8.4 ± 10.5 vs 13.1 ± 20.8 mg/l, p = 0.01). Multivariable analysis showed that atorvastatin pretreatment was independently associated with a decreased risk of CIN (odds ratios 0.34, 95% confidence interval 0.12 to 0.97, p = 0.043). Prevention of CIN with atorvastatin was paralleled by a shorter hospital stay (p = 0.007). In conclusion, short-term pretreatment with high-dose atorvastatin load prevents CIN and shortens hospital stay in patients with acute coronary syndrome undergoing PCI; anti-inflammatory effects may be involved in this renal protection. These results lend further support to early use of high-dose statins as adjuvant pharmacologic therapy before percutaneous coronary revascularization.

Atorvastatin treatment affects atrial ion currents and their tachycardia-induced remodeling in rabbits

AIMS

Atrial fibrillation (AF) leads to electrical atrial remodeling including alterations of various ion channels early after arrhythmia onset. The beneficial effects of statins in AF treatment due to their influence on oxidative stress and inflammation are discussed. Our hypothesis was that statins might also alter atrial ion currents and their early tachycardia-induced remodeling.

MAIN METHODS

Effects of an atorvastatin treatment (7 days) on atrial ion currents and their tachycardia-induced alterations were studied in a rabbit model of tachycardia-induced electrical remodeling (rapid atrial pacing (600 min) for 24 and 120 h). Ion currents (L-type calcium channel [I(Ca,L)], transient outward current [I(to)]) were measured using whole cell patch clamp method and were compared with previous experiments in untreated but also tachypaced animals.

KEY FINDINGS

Atorvastatin treatment alone decreased I(Ca,L) similar to rapid atrial pacing alone, currents were also further reduced by additional atrial tachypacing. I(to) and its pacing-induced down-regulation after 24 h were not influenced by atorvastatin treatment. However, I(to) was still reduced after 120 h in atorvastatin-treated animals and did not return to control values as expected.

SIGNIFICANCE

The present study establishes that an atorvastatin treatment can affect atrial ion currents and their tachycardia-induced remodeling in a rabbit model. These results show that-amongst other positive effects on oxidative stress and inflammation-the impact of statins on ion currents and their tachycardia-induced alterations might also play a role in "upstream" treatment of AF with HMG-CoA reductase inhibitors.

Simvastatin reduces pressor response to centrally administered angiotensin II

BACKGROUND

Angiotensin II (Ang II) plays a pivotal role in regulation of the circulatory system. Activation of angiotensin type 1 (AT1) receptors in several brain regions leads to an increase in blood pressure. Accumulating data suggest that statins affect the peripheral action of Ang II; however, their central effects are poorly recognized. The study was aimed to determine whether simvastatin interferes with the brain angiotensin system in rats.

METHODS

Twelve-week-old, Sprague-Dawley rats were divided into two groups. Untreated group was maintained on tap water, whereas simvastatin group received water containing simvastatin for the following 12 weeks. Later, both groups were subjected to experiments in which mean arterial blood pressure (MABP) and heart rate (HR) were recorded during baseline conditions and after intracerebroventricular (ICV) infusion of either saline, Ang II, or losartan.

RESULTS

ICV infusion of Ang II elicited a significant increase in MABP in both groups. However, the pressor response in the simvastatin group was significantly smaller than that in the untreated group. There was no significant change in MABP after ICV infusion of saline or losartan. ICV infusion of Ang II elicited a significant increase in HR in the untreated group but not in the simvastatin group. There was no significant change in HR after ICV infusion of saline or losartan.

CONCLUSIONS

The results show that simvastatin reduces the pressor response to ICV-infused Ang II in rats. This implies that statins may affect the central regulation of the circulatory system, especially when the brain angiotensin system is stimulated.

Statin loading before percutaneous coronary intervention: proposed mechanisms and applications

Statin therapy reduces the risk of cardiovascular events in patients with coronary artery disease. Recent in vitro and in vivo studies demonstrated a LDL-independent action of these class of drugs, which appears in modulating endothelial function, inflammation and thrombosis. Periprocedural myocardial infarction and contrast-induced nephropathy after percutaneous coronary intervention (PCI), associated with worse outcome on long-term follow-up, are both complications related to inflammatory pathogenetic mechanisms. Randomized studies demonstrated a beneficial effect of short-term statin pretreatment in reducing periprocedural cardiac marker release in patients undergoing PCI. Statin therapy before elective PCI reduces periprocedural myocardial infarction in patients with stable angina. Furthermore, an acute loading with a high dose of atorvastatin prevents myocardial damage in patients with acute coronary syndromes undergoing early PCI (<48 h). In patients already on chronic statin therapy, a reload with high-dose statins was associated with a significant improvement on 30-day major adverse cardiac event rates. Furthermore, statin therapy at the time of PCI significantly decreased the incidence of contrast-induced nephropathy. This evidence suggests an ‘upstream administration’ of short-term, high-dose statins in all patients undergoing PCI.

Basic Science Review Section: Statin Therapy—Part II: Clinical Considerations for Cardiovascular Disease

3-Hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors, commonly known as statins, are the medical treatment of choice for hypercholesterolemia. In addition to achieving a therapeutic decrease in serum cholesterol levels, statin therapy appears to promote pleiotropic effects that are independent of changes in serum cholesterol. These cholesterol lowering and pleiotropic effects are beneficial not only for the coronary circulation, but for the myocardium and peripheral arterial system as well. Patients receiving statin therapy must be carefully monitored, however, as statins potentially have harmful side effects and drug interactions. This article is part II of a 2-part review, and it focuses on the clinical aspects of statin therapy in cardiovascular disease.

Pertussis toxin up-regulates angiotensin type 1 receptors through Toll-like receptor 4-mediated Rac activation

Pertussis toxin (PTX) is recognized as a specific tool that uncouples receptors from G(i) and G(o) through ADP-ribosylation. During the study analyzing the effects of PTX on Ang II type 1 receptor (AT1R) function in cardiac fibroblasts, we found that PTX increases the number of AT1Rs and enhances AT1R-mediated response. Microarray analysis revealed that PTX increases the induction of interleukin (IL)-1beta among cytokines. Inhibition of IL-1beta suppressed the enhancement of AT1R-mediated response by PTX. PTX increased the expression of IL-1beta and AT1R through NF-kappaB, and a small GTP-binding protein, Rac, mediated PTX-induced NF-kappaB activation through NADPH oxidase-dependent production of reactive oxygen species. PTX induced biphasic increases in Rac activity, and the Rac activation in a late but not an early phase was suppressed by IL-1beta siRNA, suggesting that IL-1beta-induced Rac activation contributes to the amplification of Rac-dependent signaling induced by PTX. Furthermore, inhibition of TLR4 (Toll-like receptor 4) abolished PTX-induced Rac activation and enhancement of AT1R function. However, ADP-ribosylation of G(i)/G(o) by PTX was not affected by inhibition of TLR4. Thus, PTX binds to two receptors; one is TLR4, which activates Rac, and another is the binding site that is required for ADP-ribosylation of G(i)/G(o).

A HMGCR polymorphism is associated with relations between blood pressure and urinary sodium and potassium ratio in the Epic-Norfolk Study

A polymorphism in the HMGCR gene (rs17238540) was related to a lower response to pravastatin treatment and we aimed to investigate whether an interaction is present for this polymorphism on blood pressure (BP) and salt intake. Cross-sectional urinary sodium and potassium concentration and the polymorphism were assessed in a large population study. Participants with the mutated allele (G) had significantly higher BP than homozygous TT. There were highly significant positive trends between BP and urinary sodium:potassium ratio across quartiles in men, with less effect in women, especially women carrying the mutated allele, G. Multivariate regression showed a significant positive association between BP and the urinary sodium: potassium ratio that differed in men and women according to genotype. In men carrying the G allele, the regression slopes for diastolic BP and systolic BP were higher than in men TT and the opposite was observed in women. Our results suggest that the SNP rs17238540 in the HMGCR is associated with the BP response to urinary sodium: potassium ratio, the magnitude of the association differing according to possession of the G allele.