stilbenes and Atrial-Fibrillation

Atrial fibrillation (AF) is a common cardiac arrhythmia that is associated with increased risk for cardiovascular disease and overall mortality. Excessive alcohol intake is a well-known risk factor for AF, but this correlation is less clear with light and moderate drinking. Besides, low doses of red wine may acutely prolong repolarization and slow cardiac conduction. Resveratrol, a bioactive polyphenol found in grapes and red wine, has been linked to antiarrhythmic properties and may act as an inhibitor of both intracellular calcium release and pathological signaling cascades in AF, eliminating calcium overload and preserving the cardiomyocyte contractile function. However, there are still no clinical trials at all that prove that resveratrol supplementation leads to improved outcomes. Besides, no observational study supports a beneficial effect of light or moderate alcohol intake and a lower risk of AF. The purpose of this review is to briefly describe possible beneficial effects of red wine and resveratrol in AF, and also present studies conducted in humans regarding chronic red wine consumption, resveratrol, and AF.

Topics: Animals; Anti-Arrhythmia Agents; Antioxidants; Atrial Fibrillation; Humans; Myocytes, Cardiac; Polyphenols; Resveratrol; Stilbenes; Wine

Resveratrol is a bioactive polyphenol, found in grapes, red wine, and peanuts, and has recently garnered much media and scientific attention for its diverse beneficial health effects as a nutritional supplement or nutraceutical. Of particular interest are the well-documented cardioprotective effects of resveratrol that are mediated by diverse mechanisms, including its antioxidant and vascular effects. However, it is now becoming clear that resveratrol may also exhibit direct effects on cardiac function and rhythm through modulation of signaling pathways that regulate cardiac remodeling and ion channel activity that controls cardiac excitability. Resveratrol may therefore possess antiarrhythmic properties that contribute to the cardiovascular benefits of resveratrol. Atrial fibrillation (AF) is the most common cardiac arrhythmia, although current therapies are suboptimal. Our laboratory has been studying resveratrol's effects on cardiac ion channels and remodeling pathways, and we initiated a drug development program aimed at generating novel resveratrol derivatives with improved efficacy against AF when compared to currently available therapeutics. This review therefore focuses on the effects of resveratrol and new derivatives on a variety of cardiac ion channels and molecular pathways that contribute to the development and maintenance of atrial fibrillation.

Topics: Animals; Anti-Arrhythmia Agents; Atrial Fibrillation; Cardiotonic Agents; Humans; Resveratrol; Stilbenes

Cardiac amyloidosis is an important clinical entity associated with significant morbidity and mortality. Although the signs and symptoms can be apparent early in the disease course, diagnoses are often made late because of inadequate recognition. A diagnosis of cardiac amyloidosis requires careful scrutiny of a patient's symptoms, an electrocardiogram, and imaging studies, including echocardiography and magnetic resonance imaging. Further evaluation is required through the measurement of serum and urine light chains and the use of bone scintigraphy imaging to differentiate transthyretin amyloidosis from light-chain cardiac amyloidosis. The available treatments have expanded tremendously in recent years and have improved outcomes in the population with this disorder. Thus, it has become increasingly important to diagnose cardiac amyloidosis and provide timely therapies. This article will clarify the various misconceptions about cardiac amyloidosis and provide a framework for primary care providers to better identify this disease in their practice.

Topics: Amyloid Neuropathies, Familial; Amyloidosis; Aniline Compounds; Assisted Circulation; Atrial Fibrillation; Cardiac Imaging Techniques; Cardiomyopathies; Diagnosis, Differential; Echocardiography; Electrocardiography; Ethylene Glycols; Humans; Immunoglobulin Light-chain Amyloidosis; Magnetic Resonance Imaging; Positron-Emission Tomography; Radiopharmaceuticals; Stilbenes

The natural polyphenol resveratrol and its analogue piceatannol have various beneficial effects including antiarrhythmic properties. The aim of the present study was to examine potential electrophysiologic effects in an experimental whole-heart model of atrial fibrillation (AF). Simultaneous infusion of resveratrol (50 μmol/L) or piceatannol (10 μmol/L) in rabbit hearts resulted in an increase in atrial refractory period. Both agents induced a significant slowing of atrial conduction and of intrinsic heart rate. In both groups, a trend toward a reduction in AF and a regularization of AF was observed.

Topics: Animals; Atrial Fibrillation; Atrial Function; Dose-Response Relationship, Drug; Electrophysiological Phenomena; Heart Atria; Rabbits; Resveratrol; Stilbenes

Resveratrol has shown benefits in reducing ventricular remodeling and arrhythmias.. This study aimed to assess the therapeutic efficacy of resveratrol in reducing atrial fibrillation (AF) in a heart failure (HF) model and to explore the underlying mechanisms.. HF rabbits were created 4 weeks after undergoing coronary ligation. Group 1 (n = 6) was divided into subgroups of (a) normal rabbits, (b) HF sham rabbits, and (c) HF rabbits treated for 1 week with intraperitoneal injections of resveratrol, (d) resveratrol plus wortmannin, or (e) resveratrol plus diphenyleneiodonium chloride (DPI). All rabbits underwent epicardial catheter stimulation. Collagen content, messenger RNA and protein expression in ion channels, and phosphoinositide 3-kinase (PI3K)/AKT/endothelial nitric oxide synthase (eNOS) signaling pathways were studied in left atrial appendage (LAA) preparations. To investigate acute drug effects on left atrial electrophysiology, groups 2 a through 2e (n = 6 per group) were subjected to Langendorff perfusion.. Higher AF inducibility was found in the HF group and groups that were given PI3K and eNOS inhibitors than in the normal and resveratrol-treated groups (P < .001). Histologic analysis of the LAA revealed a decrease in fibrosis in resveratrol-treated groups compared with the HF group (8.95% ± 1.53% vs 26.62% ± 2.19%, P < .001). In real-time polymerase chain reaction analysis, ion channels including Kv1.4, Kv1.5, KvLQT1, Kir2.1, Nav1.5, Cav1.2, NCX, SERCA2a, and phospholamban were upregulated by resveratrol. PI3K, AKT, and eNOS messenger RNA and protein expression were upregulated by resveratrol but were inhibited by the coadministration of wortmannin and DPI.. Resveratrol decreases left atrial fibrosis and regulates variation in ion channels to reduce AF through the PI3K/AKT/eNOS signaling pathway.

Topics: Androstadienes; Animals; Antioxidants; Atrial Fibrillation; Disease Models, Animal; Enzyme Activation; Enzyme Inhibitors; Nitric Oxide Synthase Type III; Onium Compounds; Phosphatidylinositol 3-Kinases; Phosphorylation; Proto-Oncogene Proteins c-akt; Rabbits; Resveratrol; Signal Transduction; Stilbenes; Wine; Wortmannin

Atrial fibrillation (AF) is the most common cardiac arrhythmia and is associated with an increased risk for stroke, heart failure and cardiovascular-related mortality. Candidate targets for anti-AF drugs include a potassium channel K(v)1.5, and the ionic currents I(KACh) and late I(Na), along with increased oxidative stress and activation of NFAT-mediated gene transcription. As pharmacological management of AF is currently suboptimal, we have designed and characterized a multifunctional small molecule, compound 1 (C1), to target these ion channels and pathways.. We made whole-cell patch-clamp recordings of recombinant ion channels, human atrial I(Kur), rat atrial I(KACh), cellular recordings of contractility and calcium transient measurements in tsA201 cells, human atrial samples and rat myocytes. We also used a model of inducible AF in dogs.. C1 inhibited human peak and late K(v)1.5 currents, frequency-dependently, with IC₅₀ of 0.36 and 0.11 μmol·L(-1) respectively. C1 inhibited I(KACh)(IC₅₀ of 1.9 μmol·L(-1)) and the Na(v)1.5 sodium channel current (IC₅₀s of 3 and 1 μmol·L(-1) for peak and late components respectively). C1 (1 μmol·L(-1)) significantly delayed contractile and calcium dysfunction in rat ventricular myocytes treated with 3 nmol·L(-1) sea anemone toxin (ATX-II). C1 weakly inhibited the hERG channel and maintained antioxidant and NFAT-inhibitory properties comparable to the parent molecule, resveratrol. In a model of inducible AF in conscious dogs, C1 (1 mg·kg(-1)) reduced the average and total AF duration.. C1 behaved as a promising multifunctional small molecule targeting a number of key pathways involved in AF.

Topics: Action Potentials; Adult; Aged; Animals; Animals, Newborn; Anti-Arrhythmia Agents; Antioxidants; Atrial Fibrillation; Disease Models, Animal; Dogs; Dose-Response Relationship, Drug; ERG1 Potassium Channel; Ether-A-Go-Go Potassium Channels; Excitation Contraction Coupling; G Protein-Coupled Inwardly-Rectifying Potassium Channels; HEK293 Cells; Humans; Kv1.5 Potassium Channel; Male; Middle Aged; Myocardial Contraction; Myocytes, Cardiac; NAV1.5 Voltage-Gated Sodium Channel; NFATC Transcription Factors; Potassium Channel Blockers; Rats; Rats, Sprague-Dawley; Resveratrol; Sodium Channel Blockers; Stilbenes; Transfection