Statin and resveratrol in combination induces cardioprotection against myocardial infarction in hypercholesterolemic rat

Identification of a mechanism promoting mitochondrial sterol accumulation during myocardial ischemia-reperfusion: role of TSPO and STAR

Hypercholesterolemia is a major risk factor for coronary artery diseases and cardiac ischemic events. Cholesterol per se could also have negative effects on the myocardium, independently from hypercholesterolemia. Previously, we reported that myocardial ischemia-reperfusion induces a deleterious build-up of mitochondrial cholesterol and oxysterols, which is potentiated by hypercholesterolemia and prevented by translocator protein (TSPO) ligands. Here, we studied the mechanism by which sterols accumulate in cardiac mitochondria and promote mitochondrial dysfunction. We performed myocardial ischemia-reperfusion in rats to evaluate mitochondrial function, TSPO, and steroidogenic acute regulatory protein (STAR) levels and the related mitochondrial concentrations of sterols. Rats were treated with the cholesterol synthesis inhibitor pravastatin or the TSPO ligand 4'-chlorodiazepam. We used Tspo deleted rats, which were phenotypically characterized. Inhibition of cholesterol synthesis reduced mitochondrial sterol accumulation and protected mitochondria during myocardial ischemia-reperfusion. We found that cardiac mitochondrial sterol accumulation is the consequence of enhanced influx of cholesterol and not of the inhibition of its mitochondrial metabolism during ischemia-reperfusion. Mitochondrial cholesterol accumulation at reperfusion was related to an increase in mitochondrial STAR but not to changes in TSPO levels. 4'-Chlorodiazepam inhibited this mechanism and prevented mitochondrial sterol accumulation and mitochondrial ischemia-reperfusion injury, underlying the close cooperation between STAR and TSPO. Conversely, Tspo deletion, which did not alter cardiac phenotype, abolished the effects of 4'-chlorodiazepam. This study reveals a novel mitochondrial interaction between TSPO and STAR to promote cholesterol and deleterious sterol mitochondrial accumulation during myocardial ischemia-reperfusion. This interaction regulates mitochondrial homeostasis and plays a key role during mitochondrial injury.

Cardiovascular risk of dietary trimethylamine oxide precursors and the therapeutic potential of resveratrol and its derivatives

Overall diet, lifestyle choices, genetic predisposition, and other underlying health conditions may contribute to higher trimethylamine N-oxide (TMAO) levels and increased cardiovascular risk. This review explores the potential therapeutic ability of RSV to protect against cardiovascular diseases (CVD) and affect TMAO levels. This review considers recent studies on the association of TMAO with CVD. It also examines the sources, mechanisms, and metabolism of TMAO along with TMAO-induced cardiovascular events. Plant polyphenolic compounds, including resveratrol (RSV), and their cardioprotective mechanism of regulating TMAO levels and modifying gut microbiota are also discussed here. RSV's salient features and bioactive properties in reducing CVD have been evaluated. The close relationship between TMAO and CVD is clearly understood from currently available data, making it a potent biomarker for CVD. Precise investigation, including clinical trials, must be performed to understand RSV's mechanism, dose, effects, and derivatives as a cardioprotectant agent.

MicroRNA in the Exosomes Mediated by Resveratrol to Activate Neuronal Cells

Resveratrol (RSV), a polyphenol, is known to have a wide range of pharmacological properties in vitro. RSV may have therapeutic value for various neurodegenerative diseases via neuroprotective effects. However, it is not yet clear whether RSV can induce intestinal-brain interactions. It is assumed that the intestinal cells may secrete some factors after being stimulated by other substances. These secreted factors may activate nerve cells through gut-brain interaction, such as exosomes. In this study, it was discovered that Caco-2 cells treated with RSV secrete exosomes to activate SH-SY5Y neuronal cells. The results showed that secreted factors from RSV-treated Caco-2 cells activated SH-SY5Y. The exosomes of RSV-treated Caco-2 cells activated SH-SY5Y cells, which was manifested in the lengthening of the nerve filaments of SH-SY5Y cells. The exosomes were characterized using transmission electron microscopy and sequenced using the Illumina NovaSeq 6000 sequencer. The results showed that the miRNA expression profile of exosomes after RSV treatment changed, and twenty-six kinds of miRNAs were identified which expressed differentially between the control group and the RSV-treated group. Among them, three miRNAs were selected as candidate genes for inducing SH-SY5Y neural cell activation. Three miRNA mimics could activate SH-SY5Y neurons. These results suggested that the miRNA in intestinal exocrine cells treated with RSV may play an important role in the activation of SH-SY5Y neurons.

Resveratrol plays an anti-fibrotic and anti-autophagy role by stimulating miR-192-5p expression in urethral fibrosis

BACKGROUND

Resveratrol (RSV) exerts anti-fibrotic effects on various fibrotic diseases. Whereas the biological role of RSV on urethral fibrosis remains to be elucidated. This study aimed to determine the mechanisms by which RSV affects urethral fibrosis and autophagy.

METHODS

Sprague‒Dawley rats and primary fibroblasts were treated with transforming growth factor-β1 (TGFβ1) to generate in vivo and in vitro fibrosis models. Then, those were treated with RSV, and autophagy and fibrosis-related indicators were tested.

RESULTS

Firstly, we found that RSV reversed the upregulation of indicators related to TGFβ1-induced fibrosis (TGFβ1, α-smooth muscle actin, collagen type I, and collagen type III), autophagy (TFEB and LC3), and TGFβR1/Smad4 pathway, as well as the downregulation of p62 and miR-192-5p expression both in vivo and in vitro. Overexpression of miR-192-5p suppressed the upregulation of fibrosis-related markers expression, as well as TFEB and LC3 expression, induced by TGFβ1, while the expression trend of p62 was the opposite. Inhibiting miR-192-5p reversed the effects of RSV on the model group cells. It was also shown that RSV combined with sh-Smad4 inhibited autophagy more effectively than RSV alone.

CONCLUSION

These results suggest that RSV inhibits urinary fibrosis and autophagy via the miR-192-5p/TGFβR1/Smad4 pathway. RAV may be a potential drug for alleviating urethral fibrosis.

A pharmacological review on SIRT 1 and SIRT 2 proteins, activators, and inhibitors: Call for further research

Sirtuins or Sir (Silent information regulator) are NAD⁺-dependent enzymes playing an important part in the pathogenesis and treatment of various disorders. They have ubiquitously expressed protein deacetylases. They are implicated in several cellular activities like DNA repair, cellular metabolism, mitochondrial function, and inflammation. Deletion of sirtuin protein, SIRT1 in the organs like brain, heart, liver and pancreas can cause inflammation and increases the level of free radical ions causing oxidative stress. Inflammation and oxidative stress are closely associated with pathophysiological events in many chronic diseases, like diabetes, cancer, cardiovascular, osteoporosis, and neurodegenerative diseases. Modulation of SIRT1 gene expression might help in preventing the progression of chronic diseases related to the brain, heart, liver, and pancreas. SIRT2 proteins play an essential role in tumorigenesis, including tumor-suppressing and tumor-promoting functions. Sirtuin activators are molecules that upregulate the activity of Sirtuins in the body. Their multifaceted uses have surprised the global scientific community. They are found to control obesity, lower cardiac risks, battle cancer, etc. This article provides an update on the pharmacological effect of SIRT1 and SIRT 2 proteins, their activators and inhibitors, and their molecular mechanism. It provides novel insights for future research in targeted therapy and drug development.

Therapeutic effects of resveratrol and Omega-3 in mice atherosclerosis: focus on histopathological changes

BACKGROUND

Resveratrol and omega-3 have been shown to prevent atherosclerosis. However, histopathological changes and their comparison have not been studied well. This study investigated the therapeutic effects of resveratrol and omega-3 in experimental atherosclerosis of mice.

METHODS

We divided sixty 6-week-old male C57BL/6 mice into six groups and followed for 10 weeks: (1) standard diet, (2) atherogenic diet, (3) atherogenic diet along with resveratrol from the start of the sixth week, (4) atherogenic diet along with omega-3 from the start of the sixth week, (5) standard diet along with resveratrol from the start of the sixth week, (6) standard diet along with omega-3 from the start of the sixth week.

RESULTS

The mice fed on an atherogenic diet had a larger fat area and a thicker aortic wall thickness than mice fed on a standard diet. The use of omega-3 and resveratrol in the mice with an atherogenic diet resulted in a significantly reduced fat area (p-value = 0.003), and resveratrol had a significantly higher effect. Omega-3 or resveratrol induced a significant reduction in aortic wall thickness in mice on an atherogenic diet, and there was no significant difference between them. Among the mice with a standard diet, this study did not observe any significant changes in the fat area or the aortic wall thickness with the consumption of omega-3 or resveratrol.

CONCLUSIONS

Resveratrol and omega-3 had a regressive and therapeutic role in atherosclerosis, with a more significant effect in favor of resveratrol.

Resveratrol-Loaded Microsponge Gel for Wound Healing: In Vitro and In Vivo Characterization

Objectives

The study was aimed to formulate resveratrol (RSV) loaded microsponges to deliver drug at the wound site and incorporate it in the Moringa oleifera Lam. (Moringaceae) gel base to provide an appropriate moist environment for wound management. RSV, a stilbenoid that activates sirtuins and cell-signaling regulators involved in the process of wound healing.

Materials and Methods

Microsponges were prepared by oil in oil emulsion solvent diffusion method by optimizing the independent variables; drug: polymer ratio and volume of internal phase solvent and their effects on entrapment efficiency and particle size. Formulation batches were evaluated for drug content, production yield, entrapment efficiency, and in vitro drug release. The microsponges were further incorporated into M. oleifera gum gel, which was then evaluated for spreadability, viscosity, ex vivo diffusion study and in vivo studies using an excision wound model in rats.

Results

Scanning electron microscopy revealed spherical and porous nature of the microsponges in vitro-release study of the optimized batch of RSV microsponges showed 80.88% drug release within 8 h. Differential scanning calorimetry results revealed no drug and polymer interaction during the formation of microsponges. An ex vivo diffusion study through goat skin revealed sustained release of RSV through porous microsponges embedded in the gel base at the wound site. An in vivo study performed using an excision wound model showed wound healing and closure within day 8. Histopathology showed increased re-epithelization and reduced ulceration in RSV microsponge gel-treated group compared with sham operated.

Conclusion

RSV microsponge gel delivered the drug at the wound site and the gel base provided a moist environment and influenced cell adhesion, thereby promoting faster wound healing.

Pleiotropic properties of statins via angiogenesis modulation in cardiovascular disease

Inhibition of hydroxymethylglutaryl-coenzyme A (HMG-CoA) reductase by statins is affected by inhibiting the active site of the enzyme in a competitive manner. Statins reduce plasma cholesterol by inhibiting its de novo synthesis. In addition, statins impart 'pleiotropic' activities that do not directly relate to their ability to decrease cholesterol. The proangiogenic and antiangiogenic characteristics of statins are among these pleiotropic effects. These angiogenic-modifying properties could offer new therapeutic applications. Statins stimulate or suppress angiogenesis in a biphasic manner. Whereas low doses of statin stimulate angiogenesis, high doses reduce protein prenylation and limit cell development and angiogenesis. In this review, we discuss how statins impact angiogenesis, with a particular focus on angiogenesis in stroke and cardiovascular disease (CVD).

Role of resveratrol in inhibiting pathological cardiac remodeling

Cardiovascular disease is a group of diseases with high mortality in clinic, including hypertension, coronary heart disease, cardiomyopathy, heart valve disease, heart failure, to name a few. In the development of cardiovascular diseases, pathological cardiac remodeling is the most common cardiac pathological change, which often becomes a domino to accelerate the deterioration of the disease. Therefore, inhibiting pathological cardiac remodeling may delay the occurrence and development of cardiovascular diseases and provide patients with greater long-term benefits. Resveratrol is a non-flavonoid polyphenol compound. It mainly exists in grapes, berries, peanuts and red wine, and has cardiovascular protective effects, such as anti-oxidation, inhibiting inflammatory reaction, antithrombotic, dilating blood vessels, inhibiting apoptosis and delaying atherosclerosis. At present, the research of resveratrol has made rich progress. This review aims to summarize the possible mechanism of resveratrol against pathological cardiac remodeling, in order to provide some help for the in-depth exploration of the mechanism of inhibiting pathological cardiac remodeling and the development and research of drug targets.

Strategically designed SPEEK nanofibrous scaffold with tailored delivery ofresveratrolfor skin wound regeneration

Electro-spinnable polymeric materials can easily form two-dimensional (2D) nanofibrous scaffolds improving biochemical functionalities specially in the area of skin wound healing and nanomedicine, but it has been hard to achieve this on a highly mechanically stable biopolymer, Poly ether ether ketone (PEEK), due to its intrinsic hydrophobicity and chemical inertness. Herein, we demonstrated a novel nanomedicine healing system consisting of sulphonated poly ether ether ketone combined withresveratrol(SPEEK+RSV), which could act as an effective 2D nano bio-materialin vitroandin vivo, without observable cytotoxicity. The fabricated nanocomposites exhibited enriched skin cell proliferation and adhesion as confirmed from the results of MTT, cell adhesion and live-dead assay. Results of SEM analysis showed a uniform nano-sized distribution with adequate pore size and porosity % facilitating a desired breathable environment at the wound site. The results of FT-IR, tensile studies and TGA analyses confirmed the presence of appropriate bonds and improved mechanical stability of theRSVincorporated nanofibrous scaffold. Results of anti-microbial analysis portrayed good potentiality of the fabricated nanofibers in treating wounds colonized with bacterial infections. Controlled drug release of resveratrol established the bio-compatibility of the nanofibers in skin wound regeneration.In vivoanalysis assessed in female Wistar rats enabled complete wound closure with 100 % wound contraction within 16 days. Results of histopathology analysis through H-E and MT staining presented the re-surfing of the wound environment with regeneration of epithelium, granulation tissue and collagen. Thus, the fabricated 2D nanofibrous scaffold incorporated with pharmaceutical RSV bio-medicine perceptively mimicked skin ECM convincingly aiding the progression of skin wound regeneration mechanism.

Potential of natural products in the treatment of myocardial infarction: focus on molecular mechanisms

Although conventional drugs are widely used in the prevention and treatment of cardiovascular disease (CVD), they are being used less frequently due to concerns about possible side effects over the long term. There has been a renewed research interest in medicinal plant products, and their role in protecting the cardiovascular system and treating CVD, which are now being considered as potential alternatives to modern drugs. The most important mechanism causing damage to the myocardium after heart attack and reperfusion, is increased levels of free radicals and oxidative stress. Therefore, treatment approaches often focus on reducing free radicals or enhancing antioxidant defense mechanism. It has been previously reported that bioactive natural products can protect the heart muscle in myocardial infarction (MI). Since these compounds are readily available in fruits and vegetables, they could prevent the risk of MI if they are consumed daily. Although the benefits of a healthy diet are well known, many scientific studies have focused on whether pure natural compounds can prevent and treat MI. In this review we summarize the effects of curcumin, resveratrol, quercitin, berberine, and tanshinone on MI and CVD, and focus on their proposed molecular mechanisms of action.

Maternal resveratrol supplementation ameliorates bisphenol A-induced atherosclerotic lesions formation in adult offspring ApoE-/- mice

Current evidence suggests that intrauterine bisphenol A (BPA) exposure increases the risk of developing cardiovascular diseases in later stages of life. The beneficial effect of resveratrol (Rsv) on developmental programming of atherosclerosis lesions formation in offspring is seldom reported. Hence, we sought to study the effect of maternal Rsv in ameliorating perinatal BPA exposure-induced atherosclerosis lesions formation in adult offspring using the apolipoprotein E-deficient (ApoE^-/-) mice model. The pregnant ApoE^-/- mice were allocated into three groups: control, BPA, BPA + resveratrol (BPA + Rsv). The BPA group mice received BPA in their drinking water (1 μg/ml). BPA + Rsv group mice received BPA in their drinking water (1 μg/ml) and were treated orally with Rsv (20 mg kg^-1 day^-1). All the treatments were continued throughout the gestation and lactation period. Quantitative analysis of Sudan IV-stained aorta revealed a significantly increased area of atherosclerotic lesions in both female (p < 0.01) and male adult offspring mice (p < 0.01) in the BPA group. Supplementation with Rsv significantly reduced the BPA-induced atherosclerotic lesion development in the female offspring mice (p < 0.05). Transmission electron microscopy revealed the presence of a significantly high incidence of autophagic endothelial, smooth muscle, and macrophage cells in the aorta of BPA-exposed mice. Rsv treatment reduced the incidence of autophagic cells in BPA-exposed mice. In conclusion, maternal Rsv supplementation significantly prevents the BPA-induced atherosclerotic lesions formation in a sex-dependent manner potentially by acting as an autophagy modulator.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s13205-021-03078-y.

A Comprehensive Analysis of the Efficacy of Resveratrol in Atherosclerotic Cardiovascular Disease, Myocardial Infarction and Heart Failure

Atherosclerosis, myocardial infarction (MI) and heart failure (HF) are the main causes of mortality and morbidity around the globe. New therapies are needed to better manage ischemic heart disease and HF as existing strategies are not curative. Resveratrol is a stilbene polyphenolic compound with favorable biological effects that counter chronic diseases. Current evidence suggests that resveratrol is cardioprotective in animal models of atherosclerosis, ischemic heart disease, and HF. Though clinical studies for resveratrol have been promising, evidence remains inadequate to introduce it to the clinical setting. In this narrative review, we have comprehensively discussed the relevant compelling evidence regarding the efficacy of resveratrol as a new therapeutic agent for the management of atherosclerosis, MI and HF.

Resveratrol Ameliorates Cardiac Remodeling in a Murine Model of Heart Failure With Preserved Ejection Fraction

Objective: Accumulating evidence suggested that resveratrol (RES) could protect against adverse cardiac remodeling induced by several cardiovascular diseases. However, the role of RES in the setting of heart failure with preserved ejection fraction (HFpEF) and the underlying mechanisms of its action remain understood. This study was to determine whether RES could ameliorate HFpEF-induced cardiac remodeling and its mechanisms.

Methods:In vivo, C57BL/6 mice served as either the sham or the HFpEF model. The HFpEF mice model was induced by uninephrectomy surgery and d-aldosterone infusion. RES (10 mg/kg/day, ig) or saline was administered to the mice for four weeks. In vitro, transforming growth factor β1 (TGF-β1) was used to stimulate neonatal rat cardiac fibroblasts (CFs) and Ex-527 was used to inhibit sirtuin 1 (Sirt1) in CFs. Echocardiography, hemodynamics, western blotting, quantitative real-time PCR, histological analysis, immunofluorescence, and ELISA kits were used to evaluate cardiac remodeling induced by HFpEF. Sirt1 and Smad3 expressions were measured to explore the underlying mechanisms of RES.

Results: HFpEF mice developed left ventricular hypertrophy, preserved ejection fraction, diastolic dysfunction, and pulmonary congestion. Moreover, HFpEF mice showed increased infiltration of neutrophils and macrophages into the heart, including increased interleukin (IL)-1β, IL-6, and TNF-α. We also observed elevated M1 macrophages and decreased M2 macrophages, which were exhibited by increased mRNA expression of M1 markers (iNOS, CD86, and CD80) and decreased mRNA expression of M2 markers (Arg1, CD163, and CD206) in HFpEF hearts. Moreover, HFpEF hearts showed increased levels of intracellular reactive oxygen species (ROS). Importantly, HFpEF mice depicted increased collagen-I and -III and TGF-β mRNA expressions and decreased protein expression of phosphorylated endothelial nitric-oxide synthase (p-eNOS). Results of western blot revealed that the activated TGF-β/Smad3 signaling pathway mediated HFpEF-induced cardiac remodeling. As expected, this HFpEF-induced cardiac remodeling was reversed when treated with RES. RES significantly decreased Smad3 acetylation and inhibited Smad3 transcriptional activity induced by HFpEF via activating Sirt1. Inhibited Sirt1 with Ex-527 increased Smad3 acetylation, enhanced Smad3 transcriptional activity, and offset the protective effect of RES on TGF-β–induced cardiac fibroblast–myofibroblast transformation in CFs.

Conclusion: Our results suggested that RES exerts a protective action against HFpEF-induced adverse cardiac remodeling by decreasing Smad3 acetylation and transcriptional activity via activating Sirt1. RES is expected to be a novel therapy option for HFpEF patients.

Medicinal plants and bioactive natural compounds as inhibitors of HMG-CoA reductase: A literature review

Cardiovascular diseases (CVDs) are one of the most important causes for mortality worldwide. Elevated levels of total cholesterol, and particularly LDL-cholesterol (LDL-C) are the main risk factor for acute myocardial infarction (AMI) and ischemic heart disease. The risk of CVDs could be reduced by decreasing the elevated cholesterol levels. β-hydroxy β-methylglutaryl-CoA reductase (HMGCoAR) is the primary and rate-limiting enzyme in the cholesterol biosynthesis pathway. Recently, the crucial role of nutraceuticals in maintaining normal physiological function was established. Nutraceuticals play an important role in preventing several non-communicable diseases such as obesity, CVDs, cancer, diabetes, and reducing hyperlipidemia. Although the effect of nutraceuticals and herbal medicine on CVDs and dyslipidemia was previously investigated thoroughly, the effect of these natural products on HMGCoAR as one of the important enzymes involved in CVDs etiopathogenesis has not yet been investigated. Therefore, the major aim of this paper was to review the effects of nutraceuticals and medicinal plants on HMGCoAR. Results indicate that different types of natural foods, isolated nutrients, herbal products, and dietary supplements as nutraceuticals decrease the expression and activity of HMGCoAR. This review shows that medicinal plants and nutraceuticals could be used to decrease HMGCoAR activity as accessible and convenient and economical natural compounds to prevent dyslipidemia and CVDs.

Pharmacological Inhibition of PTEN Restores Remote Ischemic Postconditioning Cardioprotection in Hypercholesterolemic Mice: Potential Role of PTEN/AKT/GSK3β SIGNALS

Although remote ischemic postconditioning (RIPC) was shown to confer cardioprotection against myocardial ischemia/reperfusion (I/R) injury in normal animals, whether RIPC-induced cardioprotection is altered in the presence of hypercholesterolemia, a comorbidity with acute myocardial infarction (AMI) patients has yet to be determined. Normal or 2% cholesterol chow was fed to male C57BL/6J mice for 12 weeks to induce hypercholesterolemia, then normal or hypercholesterolemic murine hearts were exposed to AMI by coronary artery ligation. RIPC was induced by four episodes of 5 min femoral artery occlusion followed by 5 min reperfusion immediately after myocardial reperfusion in mice. Following I/R, RIPC significantly attenuated postischemic infarct size, hindered cardiomyocyte apoptosis, improved cardiac systolic function, decreased phosphatase and tensin homolog deleted on chromosome ten (PTEN) expression, and further increased Akt and GSK-3β phosphorylation in non-hypercholesterolemic, but not in hypercholesterolemic mice. Application of the PTEN inhibitor bisperoxovanadium (BpV) (1.0 mg/kg) reduced postischemic infarct size, attenuated cardiomyocyte apoptosis, and improved cardiac dysfunction in normal, but not in hypercholesterolemic mice. Further, increased dose of BpV (2 mg/kg or 10 mg/kg) failed to rescue the detrimental effects of hypercholesterolemia on I/R in mice following I/R. Especially important, we demonstrated that the combination BpV and RIPC exerted marked cardioprotective effects both in normal and hypercholesterolemic mice with I/R, indicating that PTEN inhibition restores RIPC-elicited myocardial protection in the presence of hypercholesterolemia. Our results demonstrated that hypercholesterolemia attenuated RIPC-induced cardioprotection against I/R injury by alteration of PTEN/Akt/GSK3β signals, and inhibition of PTEN rescued RIPC-induced cardioprotection in the presence of hypercholesterolemia.

SIRT1 Activation by Equisetum Arvense L. (Horsetail) Modulates Insulin Sensitivity in Streptozotocin Induced Diabetic Rats

BACKGROUND: Equisetum arvense L., commonly known as field horsetail is a perennial fern of which extracts are rich sources of phenolic compounds, flavonoids, and phenolic acids. Activation of SIRT1 that was shown to be involved in well-known signal pathways of diabetic cardiomyopathy has a protective effect against oxidative stress, inflammatory processes, and apoptosis that are the basis of diseases such as obesity, diabetes mellitus, or cardiovascular diseases. The aim of our study was to evaluate the antidiabetic and cardioprotective effects of horsetail extract in streptozotocin induced diabetic rats. METHODS: Diabetes was induced by a single intraperitoneal injection of 45 mg/kg streptozotocin. In the control groups (healthy and diabetic), rats were administered with vehicle, whilst in the treated groups, animals were administered with 50, 100, or 200 mg/kg horsetail extract, respectively, for six weeks. Blood glucose levels, glucose tolerance, and insulin sensitivity were determined, and SIRT1 levels were measured from the cardiac muscle. RESULTS: The horsetail extract showed moderate beneficial changes in blood glucose levels and exhibited a tendency to elevate SIRT1 levels in cardiomyocytes, furthermore a 100 mg/kg dose also improved insulin sensitivity. CONCLUSIONS: Altogether our results suggest that horsetail extract might have potential in ameliorating manifested cardiomyopathy acting on SIRT1.

Resveratrol ameliorates atherosclerosis induced by high-fat diet and LPS in ApoE-/- mice and inhibits the activation of CD4+ T cells

Background

Atherosclerosis (AS), which characterized with the accumulation of lipids on the vessel wall, is the pathological basis of many cardiovascular diseases (CVD) and seriously threatens human health. Resveratrol (RES) has been reported to be benefit for AS treatment. This research aimed to observe the effects of RES on AS induced by high-fat diet (HFD) and LPS in ApoE^-/- mice and investigate the underlying mechanism.

Methods

ApoE^-/- mice were fed with HFD companied with LPS to induce AS and RES was administrated for 20 weeks. Splenic CD4⁺ T cells were cultured and treated with anti-CD3/CD28 together with LPS, and RES was added. Serum lipids and the atherosclerotic areas of aortas were detected. The activation of CD4⁺ T cells were investigated both in vivo and in vitro and the expression of DNA methyltransferases (Dnmt) in CD4⁺ T cells were measured.

Results

In vivo, administration of RES prevented HFD and LPS induced dysfunction of serum lipids including TC (total cholesterol), TG (triglyceride), LDL-C (low density lipoprotein cholesterol) and HDL-C (high density lipoprotein cholesterol), ameliorated the thickened coronary artery wall and decreased the areas of atherosclerotic lesion on aortas. Besides, RES decreased the number of CD4⁺ T cells in peripheral blood, decreased the expression of CD25 and CD44, but not affected the expression of L-selectin (CD62L). In vitro, RES decreased the expression of Ki67, CD25 and CD44 in CD4⁺ T cells. Moreover, RES increased the secretion of IL-2, IL-10 and TGF-β1, decreased IL-6. In addition, RES decreased both the mRNA and protein level of Dnmt1 and Dnmt3b in CD4⁺ T cells.

Conclusion

These results indicated that RES ameliorated AS induced by HFD companied with LPS in ApoE^-/- mice, inhibited the proliferation and activation of CD4⁺ T cells and regulated the expression of Dnmt1 and Dnmt3b.

Resveratrol for protection against statin toxicity in C2C12 and H9c2 cells

Statins are among the most commonly prescribed drugs for the treatment of high blood cholesterol. Myotoxicity of statins in certain individuals is often a severe side effect leading to withdrawal. Using C2C12 and H9c2 cells, both exhibiting characteristics of skeletal muscle cells, we addressed whether resveratrol (RSV) can prevent statin toxicity. Statins decreased cell viability in a dose and time-dependent manner. Among the five statins tested, atorvastatin, simvastatin, lovastatin, pravastatin, and fluvastatin, simvastatin is the most toxic one. Simvastatin at 10 µM caused about 65% loss of metabolic activity as measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays in C2C12 cells or H9c2 cells. Inhibition of metabolic activity correlates with an increase in caspase activity. RSV was found to protect H9c2 cells from simvastatin-induced activation of caspase-3/7. However, such protection was not found in C2C12 cells. This cell type-dependent effect of RSV adds to the complexity in muscle cell toxicity of statins.

Pharmacological basis and new insights of resveratrol action in the cardiovascular system

Resveratrol (trans-3,4',5-trihydroxystilbene) belongs to the family of natural phytoalexins. Resveratrol first came to our attention in 1992, following reports of the cardioprotective effects of red wine. Thereafter, resveratrol was shown to exert antioxidant, anti-inflammatory, anti-proliferative, and angio-regulatory effects against atherosclerosis, ischaemia, and cardiomyopathy. This article critically reviews the current findings on the molecular basis of resveratrol-mediated cardiovascular benefits, summarizing the broad effects of resveratrol on longevity regulation, energy metabolism, stress resistance, exercise mimetics, circadian clock, and microbiota composition. In addition, this article also provides an update, both preclinically and clinically, on resveratrol-induced cardiovascular protection and discusses the adverse and inconsistent effects of resveratrol reported in both preclinical and clinical studies. Although resveratrol has been claimed as a master anti-aging agent against several age-associated diseases, further detailed mechanistic investigation is still required to thoroughly unravel the therapeutic value of resveratrol against cardiovascular diseases at different stages of disease development. LINKED ARTICLES: This article is part of a themed section on The Pharmacology of Nutraceuticals. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v177.6/issuetoc.

The Fluid Aspect of the Mediterranean Diet in the Prevention and Management of Cardiovascular Disease and Diabetes: The Role of Polyphenol Content in Moderate Consumption of Wine and Olive Oil

A growing interest has emerged in the beneficial effects of plant-based diets for the prevention of cardiovascular disease, diabetes and obesity. The Mediterranean diet, one of the most widely evaluated dietary patterns in scientific literature, includes in its nutrients two fluid foods: olive oil, as the main source of fats, and a low-to-moderate consumption of wine, mainly red, particularly during meals. Current mechanisms underlying the beneficial effects of the Mediterranean diet include a reduction in inflammatory and oxidative stress markers, improvement in lipid profile, insulin sensitivity and endothelial function, as well as antithrombotic properties. Most of these effects are attributable to bioactive ingredients including polyphenols, mono- and poly-unsaturated fatty acids. Polyphenols are a heterogeneous group of phytochemicals containing phenol rings. The principal classes of red wine polyphenols include flavonols (quercetin and myricetin), flavanols (catechin and epicatechin), anthocyanin and stilbenes (resveratrol). Olive oil has at least 30 phenolic compounds. Among them, the main are simple phenols (tyrosol and hydroxytyrosol), secoroids and lignans. The present narrative review focuses on phenols, part of red wine and virgin olive oil, discussing the evidence of their effects on lipids, blood pressure, atheromatous plaque and glucose metabolism.

In vivo anti-hypercholesterolemic effect of buttermilk, milk fat globule membrane and Enterococcus faecium FFNL-12

The present study was undertaken to evaluate the hypocholesterolemic activity of buttermilk, milk fat globule membrane (MFGM) and Enterococcus faecium FFNL-12 in rat model. Thirty-sixth male Abino rats were divided into six groups. The first one (coded as G1) was fed a standard diet containing 10% corn oil as fat source while remaining five (coded G2 to G6) were fed hypercholesterolemic diets in which oil was replaced with animal grease. Animals subjected to treatment G1 served as healthy control while those in G2 were assigned as hypocholesterolemic animals which did not receive any treatment. The remaining experimental groups were designed to assess the hypocholesterolemic effect of intragastric adminstartion of dose of 109 CFU/Kg body weight of Enterococcus faecium FFNL-12 (G3), Enterococcus faecium FFNL-12/butter milk (G4), buttermilk (G5) and milk fat globule membrane (MFGM). After four weeks, animals were evaluated in relation to growth, fecal pH, organs weight, serum lipid profile, antioxidant activity of liver tissue, liver and heart function and liver histopathological architecture. Results revealed that animals fed hypercholesterolemic diet (G2-G6) had significantly lower faecal pH and liver weight compared with those fed standard diet (G1). Treatments applied to animals fed hypercholesterolemic diet with the above mentioned additions (G3 to G6) appeared to improve both cardiac and hepatic functions, serum lipid profile and glucose concentration and liver histopathological architecture compared with animals subjected to G2 treatment. In most cases, treatment with MFGM appeared to be the most effective to avoid adverse effects associated to feeding hypercholesterolemic diet. MFGM fraction as well as E. faecium FFNL-12/buttermilk combination were effective in reducing serum lipids and glucose levels to the normal range. This combination also had potential antioxidant activity and ability to improve liver and heart functions.

Resveratrol supplementation improves metabolic control in rats with induced hyperlipidemia and type 2 diabetes

Resveratrol was recognized as the major factor responsible for the beneficial properties of red wine. Several resveratrol-based dietary supplements are available, but their efficacy has not been sufficiently tested. This study was designed to examine the effect of resveratrol supplementation, using a commercially available product, on the metabolic status of experimental animals with induced hyperlipidemia or type 2 diabetes mellitus (T2DM). Hyperlipidemia was induced by feeding the rats a standard pellet diet supplemented with cholesterol. T2DM was induced by adding 10% fructose to drinking water and streptozotocin. Treatment with resveratrol-based supplement improved glycemic control in diabetic animals and significantly decreased serum low-density-lipoprotein (LDL) and triglyceride levels, concurrently increasing the high-density-lipoprotein (HDL) levels in animals with hyperlipidemia. Resveratrol-treated animals had improved tolerance to glucose loading. Supplementation did not induce alterations in parameters of liver and renal function. Findings indicate that commercial resveratrol supplement improves metabolic control in rats with induced hyperlipidemia and T2DM.

Dyslipidemia in Ischemia/Reperfusion Injury

Ischemic heart disease is the main cause of morbidity and mortality in the developed world. Although reperfusion therapies are currently the best treatment for this entity, the restoration of blood flow leads, under certain circumstances, to a form of myocardial damage called reperfusion injury. Several studies have shown that age, sex, smoking, diabetes and dyslipidemia are risk factors for cardiovascular diseases. Among these risk factors, dyslipidemias are present in 40% of patients with ischemic heart disease and represent the clinical factor with the greatest impact on the prognosis of patients with cardiovascular diseases. It is known that during reperfusion the increase of the oxidative stress is perhaps one of the most important mechanisms implicated in cell damage. That is why several researchers have studied protective mechanisms against reperfusion injury, such as the ischemic pre- and post- conditioning, making emphasis mainly on the reduction of oxidative stress. However, few of these efforts have been successfully translated into the clinical setting. The controversial results in regards to the relation between cardioprotective mechanisms and dyslipidemia/hypercholesterolemia are mainly due to the difference among quality, composition and the time of administration of hypercholesterolemic diets, as well as the difference in the species used in each of the studies. Therefore, in order to compare results, it is crucial that all variables that could modify the obtained results are taken into consideration.

Combination of Berberine with Resveratrol Improves the Lipid-Lowering Efficacy

The natural compound berberine has been reported to exhibit anti-diabetic activity and to improve disordered lipid metabolism. In our previous study, we found that such compounds upregulate expression of sirtuin 1—a key molecule in caloric restriction, it is, therefore, of great interest to examine the lipid-lowering activity of berberine in combination with a sirtuin 1 activator resveratrol. Our results showed that combination of berberine with resveratrol had enhanced hypolipidemic effects in high fat diet-induced mice and was able to decrease the lipid accumulation in adipocytes to a level significantly lower than that in monotherapies. In the high fat diet-induced hyperlipidemic mice, combination of berberine (30 mg/kg/day, oral) with resveratrol (20 mg/kg/day, oral) reduced serum total cholesterol by 27.4% ± 2.2%, and low-density lipoprotein-cholesterol by 31.6% ± 3.2%, which was more effective than that of the resveratrol (8.4% ± 2.3%, 6.6% ± 2.1%) or berberine (10.5% ± 1.95%, 9.8% ± 2.58%) monotherapy (p < 0.05 for both). In 3T3-L1 adipocytes, the treatment of 12 µmol/L or 20 µmol/L berberine combined with 25 µmol/L resveratrol showed a more significant inhibition of lipid accumulation observed by Oil red O stain compared with individual compounds. Moreover, resveratrol could increase the amount of intracellular berberine in hepatic L02 cells. In addition, the combination of berberine with resveratrol significantly increases the low-density-lipoprotein receptor expression in HepG2 cells to a level about one-fold higher in comparison to individual compound. These results implied that the enhanced effect of the combination of berberine with resveratrol on lipid-lowering may be associated with upregulation of low-density-lipoprotein receptor, and could be an effective therapy for hyperlipidemia in some obese-associated disease, such as type II diabetes and metabolic syndrome.

What's in wine? A clinician's perspective<sup/>

Alcoholic beverages, specifically wine, have been consumed for many years. Wine is postulated to play an important role in the improvement of cardiovascular risk factors. Most epidemiological studies have found sustained consumption at light-to-moderate amounts to increase HDL cholesterol, reduce platelet aggregation, and promote fibrinolysis. Wine consumption has been inversely associated with ischemic heart disease, and the alcohol-blood pressure association, in most studies, follows a J-shaped curve. These outcomes have been attributed to the molecular constituents of wine, namely ethanol and polyphenols. Due to the continued interest in wine as a biological beverage, we review the chemistry of wine as clinicians, including its chemical composition, viticulture and enological practices, and other chemical factors that influence the bioactive components of wine. We also outline the biological effects of wine components and directions for future research.

Sigma-1 Receptor Stimulation with PRE-084 Ameliorates Myocardial Ischemia-Reperfusion Injury in Rats

BACKGROUND

The sigma receptors are a relatively novel receptor group with respect to knowledge of their effect on health. Although the sigma-1 receptor agonist PRE-084 exhibits a cardioprotective effect in some studies, the benefits in cases of myocardial ischemia/reperfusion (I/R) are not clear. The aim of this study was to explore the mechanism of action and assess the effect of PRE-084 on myocardial I/R injury in rats.

METHODS

In this study, rats were assigned randomly to three groups with computer (n = 14 for each group): a sham group, an I/R group, and a PRE-084 group. In the PRE-084 group, rats were administered PRE-084 1 h before operation. In the myocardial I/R model, the left anterior descending branch of rats was ligated and opened half an hour later. Cardiac function was assessed, and the apoptosis index was evaluated. The mechanisms of the cardioprotective effects of PRE-084 were explored.

RESULTS

PRE-084 pretreatment preserved cardiac function and reduced myocardial apoptosis (F = 86.0, P < 0.01) with Western blotting analysis, showing significantly reduced expression of Bax (F = 75.7, P < 0.01) and cleaved-caspase 3 (F = 44.7, P < 0.01), along with increased expression of the Bcl-2 protein (P < 0.01) and phosphorylated protein kinase B (p-Akt) (P < 0.01) and phosphorylated-endothelial nitric oxide synthase (p-eNOS; P < 0.01).

CONCLUSION

PRE-084 preserved cardiac function and reduced myocardial apoptosis through the activation of Akt and eNOS.

Hypercholesterolemia-Induced Loss of Flow-Induced Vasodilation and Lesion Formation in Apolipoprotein E-Deficient Mice Critically Depend on Inwardly Rectifying K+ Channels

BACKGROUND

Hypercholesterolemia-induced decreased availability of nitric oxide (NO) is a major factor in cardiovascular disease. We previously established that cholesterol suppresses endothelial inwardly rectifying K+ (Kir) channels and that Kir2.1 is an upstream mediator of flow-induced NO production. Therefore, we tested the hypothesis that suppression of Kir2.1 is responsible for hypercholesterolemia-induced inhibition of flow-induced NO production and flow-induced vasodilation (FIV). We also tested the role of Kir2.1 in the development of atherosclerotic lesions.

METHODS AND RESULTS

Kir2.1 currents are significantly suppressed in microvascular endothelial cells exposed to acetylated-low-density lipoprotein or isolated from apolipoprotein E-deficient (Apoe-/- ) mice and rescued by cholesterol depletion. Genetic deficiency of Kir2.1 on the background of hypercholesterolemic Apoe-/- mice, Kir2.1+/-/Apoe-/- exhibit the same blunted FIV and flow-induced NO response as Apoe-/- or Kir2.1+/- alone, but while FIV in Apoe-/- mice can be rescued by cholesterol depletion, in Kir2.1+/-/Apoe-/- mice cholesterol depletion has no effect on FIV. Endothelial-specific overexpression of Kir2.1 in arteries from Apoe-/- and Kir2.1+/-/Apoe-/- mice results in full rescue of FIV and NO production in Apoe-/- mice with and without the addition of a high-fat diet. Conversely, endothelial-specific expression of dominant-negative Kir2.1 results in the opposite effect. Kir2.1+/-/Apoe-/- mice also show increased lesion formation, particularly in the atheroresistant area of descending aorta.

CONCLUSIONS

We conclude that hypercholesterolemia-induced reduction in FIV is largely attributable to cholesterol suppression of Kir2.1 function via the loss of flow-induced NO production, whereas the stages downstream of flow-induced Kir2.1 activation appear to be mostly intact. Kir2.1 channels also have an atheroprotective role.

Hypercholesterolemia Abrogates Remote Ischemic Preconditioning-Induced Cardioprotection: Role of Reperfusion Injury Salvage Kinase Signals

Remote ischemic preconditioning (RIPC) is one of the most powerful intrinsic cardioprotective strategies discovered so far and experimental data indicate that comorbidity may interfere with the protection by RIPC. Therefore, we investigate whether RIPC-induced cardioprotection was intact in hypercholesterolemic rat hearts exposed to ischemia reperfusion in vivo. Normal or hypercholesterolemic rat hearts were exposed to 30 min of ischemia and 2 h of reperfusion, with or without RIPC, PI3K inhibitor wortmannin, MEK-ERK1/2 inhibitor PD98059, GSK3β inhibitor SB216763. Infarct size, apoptosis, MG53, PI3K-p85, p-Akt, p-ERK1/2, p-GSK3β, and cleaved Caspase-3 were determined. RIPC reduced infarct size, limited cardiomyocyte apoptosis following IR that was blocked by wortmannin but not PD98059. RIPC triggered unique cardioprotective signaling including MG53, phosphorylation of Akt, and glycogen synthase kinase-3ß (GSK3β) in concert with reduced proapoptotic active caspase-3. In contrast, RIPC failed to reduce myocardial necrosis and apoptosis as well as to increase the phosphorylated Akt and GSK3β in hypercholestorolemic myocardium. Importantly, we found that inhibition of GSK with SB216763 reduced myocardial infarct size in healthy and hypercholesterolemic hearts, but no additional cardioprotective effect was achieved when combined with RIPC. Our results suggest that acute GSK3β inhibition may provide a novel therapeutic strategy for hypercholesterolemic patients during acute myocardial infarction, whereas RIPC is less effective due to signaling events that adversely affect GSK3β.

Protective effects of Xinji'erkang on myocardial infarction induced cardiac injury in mice

BACKGROUND

Myocardial infarction (MI) is a major risk factor responsible for morbidity and mortality. Xinji'erkang (XJEK) has been clinically used as an effective medication in the treatment of coronary heart disease and myocarditis. The purpose of this study was to investigate the cardioprotective effect of Xinji'erkang on MI mice.

METHODS

Forty male mice were randomly assigned into four groups as follows (n = 10): sham, model, MI with administration of XJEK and fosinopril for four weeks. At the end of studies, hemodynamic parameters and electrocardiography (ECG) were recorded. Heart and body mass were measured and heart weight/body weight (HW/BW) ratio was calculated as index of hypertrophy. The hypertrophy of heart and aorta was examined using the hematoxylin and eosin (HE) staining, and the collagen deposition was evaluated using Van Gieson (VG) staining. Serum nitric oxide level (NO), superoxide dismutase (SOD) activity and malondialdehyde (MDA) concentration were assayed by colorimetric analysis. The expressions of endothelial NO synthetase (eNOS) expression in serum and cardiac tissues were determined using ELISA assay and immunohistochemistry. Angiotensin II (Ang II) in serum and cardiac tissues was measured using ELISA assay. Besides, tumor necrosis factor-α (TNF-α), interleukin1β (IL-1β) and interleukin10 (IL-10) were observed in cardiac tissues with ELISA assay as well.

RESULTS

The administration of XJEK significantly improved cardiac dysfunction and abnormal ECG with reduced HW/BW ratio and ameliorated cardiomyocyte hypertrophy and collagen deposition compared to MI, which was partly due to the decreased SOD and increased MDA in serum. Moreover, XJEK treatment also improved endothelial dysfunction (ED) with not only enhanced eNOS activities in serum and cardiac tissues and elevated NO levels in serum, but also decreased Ang II content in serum and cardiac tissues. Finally, protein expressions of pro-inflammation cytokines, TNF-α and IL-1β in the cardiac tissues with XJEK treatment were significantly decreased compared to model. On the contrary, IL-10, an anti-inflammatory cytokine concentrated in cardiac tissues was significantly enhanced compared to model.

CONCLUSION

Xinji'erkang exerts cardioprotective effect on myocardial infarction in mice, which may be due to the improvement of endothelial dysfunction and the reduction of oxidative stress and inflammation response.

Effect of hypercholesterolaemia on myocardial function, ischaemia-reperfusion injury and cardioprotection by preconditioning, postconditioning and remote conditioning

Hypercholesterolaemia is considered to be a principle risk factor for cardiovascular disease, having direct negative effects on the myocardium itself, in addition to the development of atherosclerosis. Since hypercholesterolaemia affects the global cardiac gene expression profile, among many other factors, it results in increased myocardial oxidative stress, mitochondrial dysfunction and inflammation triggered apoptosis, all of which may account for myocardial dysfunction and increased susceptibility of the myocardium to infarction. In addition, numerous experimental and clinical studies have revealed that hyperlcholesterolaemia may interfere with the cardioprotective potential of conditioning mechanisms. Although not fully elucidated, the underlying mechanisms for the lost cardioprotection in hypercholesterolaemic animals have been reported to involve dysregulation of the endothelial NOS-cGMP, reperfusion injury salvage kinase, peroxynitrite-MMP2 signalling pathways, modulation of ATP-sensitive potassium channels and apoptotic pathways. In this review article, we summarize the current knowledge on the effect of hypercholesterolaemia on the non-ischaemic and ischaemic heart as well as on the cardioprotection induced by drugs or ischaemic preconditioning, postconditioning and remote conditioning. Future perspectives concerning the mechanisms and the design of preclinical and clinical trials are highlighted.

LINKED ARTICLES

This article is part of a themed section on Redox Biology and Oxidative Stress in Health and Disease. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.12/issuetoc.

Resveratrol activates endogenous cardiac stem cells and improves myocardial regeneration following acute myocardial infarction

Stem cell antigen-1-positive (Sca-1+) cardiac stem cells (CSCs) therapy for myocardial regeneration following acute myocardial infarction (AMI) is limited by insufficient cell viability and a high rate of apoptosis, due to the poor regional microenvironment. Resveratrol, which is a compound extracted from red wine, has been reported to protect myocardial tissue post‑AMI by increasing the expression of angiogenic and chemotactic factors. The present study aimed to investigate the effects of resveratrol on Sca‑1+ CSCs, and to optimize Sca‑1+ CSCs therapy for myocardial regeneration post‑AMI. C57/BL6 mice (age, 6 weeks) were divided into two groups, which received intragastric administration of PBS or 2.5 mg/kg.d resveratrol. The endogenous expression of Sca‑1+ CSCs in the heart was assessed on day 7. Furthermore, C57/BL6 mice underwent left anterior descending coronary artery ligation for the construction of an AMI model, and received an injection of 1x106 CSCs into the peri‑ischemic area (n=8/group). Mice received intragastric administration of PBS or resveratrol (2.5 mg/kg.d) for 4 weeks after cell transplantation. Echocardiography was used to evaluate cardiac function 4 weeks after cell transplantation. Capillary density and cardiomyocyte apoptosis in the peri‑ischemic myocardium were assessed by cluster of differentiation 31 immunofluorescent staining and terminal deoxynucleotidyl transferase‑mediated dUTP nick end labeling assay, respectively. Western blot analysis was conducted to detect the protein expression levels of vascular endothelial growth factor (VEGF) and stromal cell‑derived factor (SDF)‑1α in the myocardium. Treatment with resveratrol increased the number of endogenous Sca‑1+ CSCs in heart tissue after 7 days (PBS vs. Res, 1.85±0.41/field vs. 3.14±0.26/field, P<0.05). Furthermore, intragastric administration of resveratrol significantly increased left ventricle (LV) function 4 weeks after AMI, as determined by an increase in LV fractional shortening (CSCs vs. Res + CSCs, 28.82±1.58% vs. 31.18±2.02%, P<0.05), reduced LV end‑diastolic diameter (CSCs vs. Res + CSCs, 0.37±0.01 mm vs. 0.35±0.02 mm, P<0.05), and reduced LV end‑systolic diameter (CSCs vs. Res + CSCs, 0.26±0.01 mm vs. 0.23±0.02 mm, P<0.05). These protective effects were predominantly achieved via an increase in capillary density (CSCs vs. Res + CSCs, 281.02±24.08/field vs. 329.75±36.69/field, P<0.05) and a reduction in cardiomyocyte apoptosis (CSCs vs. Res + CSCs, 1.5±0.54/field vs. 0.83±0.40/field, P<0.05) in peri‑ischemic myocardium. Western blot analysis indicated that VEGF and SDF‑1α were upregulated in resveratrol‑treated myocardium after a 7 day treatment or 4 weeks after AMI (7 days VEGF PBS vs. Res, 0.89±0.07 vs. 1.21±0.02, P<0.05; SDF‑1α PBS vs. Res, 0.66±0.04 vs. 1.33±0.04, P<0.05; 4 weeks VEGF CSCs vs. Res + CSCs, 0.54±0.03 vs. 0.93±0.13, P<0.05; SDF‑1α CSCs vs. Res + CSCs, 0.53±0.03 vs. 0.93±0.03, P<0.05). Resveratrol activated endogenous CSCs, increased capillary density and decreased cardiomyocyte apoptosis in the peri‑ischemic myocardium, and augmented the effects of CSCs transplantation. These effects may be caused by the upregulation of VEGF and SDF‑1α.

LRP5/canonical Wnt signalling and healing of ischemic myocardium

LRP5 (low-density lipoprotein receptor-related protein 5) activates canonical Wnt signalling. LRP5 plays multiple roles including regulation of lipoprotein and cholesterol homeostasis as well as innate immunity cell function. However, it is not known whether LRP5 has a role in the myocardium. The aim of this study was to investigate LRP5 and Wnt signalling in myocardial remodelling after acute myocardial infarction (MI). Wnt protein levels were determined in a hypercholesterolemic porcine model of MI, in Lrp5 ^-/- C57Bl6 mice, in cultured cardiomyocytes and in human explanted hearts with previous MI episodes. 21 days post-MI, there was upregulation of LRP5 in the ischemic myocardium of hypercholesterolemic pigs as well as an upregulated expression of proteins of the Wnt pathway. We demonstrate via overexpression and silencing experiments that LRP5 induces Wnt pathway activation in isolated cardiomyocytes. Hypoxia and lipid-loading induced the expression of Wnt proteins, whereas this effect is blocked in LRP5-silenced cardiomyocytes. To characterize the function of the LRP5-Wnt axis upregulation in the heart, we induced MI in wild-type and Lrp5 ^-/- mice. Lrp5 ^-/- mice had significantly larger infarcts than Wt mice, indicating a protective role of LRP5 in injured myocardium. The LRP5 upregulation in post-MI hearts seen in pigs and mice was also evident in human hearts as dyslipidemic patients with previous episodes of ischemia have higher expression of LRP5 and Wnt-signalling genes than non-ischemic dilated hearts. We demonstrate an upregulation of LRP5 and the Wnt signalling pathway that it is a prosurvival healing response of cardiomyocytes upon injury.

Resveratrol attenuates cortical neuron activity: roles of large conductance calcium-activated potassium channels and voltage-gated sodium channels

Background

Resveratrol, a phytoalexin found in grapes and red wine, exhibits diverse pharmacological activities. However, relatively little is known about whether resveratrol modulates the ion channels in cortical neurons. The large-conductance calcium-activated potassium channels (BK_Ca) and voltage-gated sodium channels were expressed in cortical neurons and play important roles in regulation of neuronal excitability. The present study aimed to determine the effects of resveratrol on BK_Ca currents and voltage-gated sodium currents in cortical neurons.

Results

Resveratrol concentration-dependently increased the current amplitude and the opening activity of BK_Ca channels, but suppressed the amplitude of voltage-gated sodium currents. Similar to the BK_Ca channel opener NS1619, resveratrol decreased the firing rate of action potentials. In addition, the enhancing effects of BK_Ca channel blockers tetraethylammonium (TEA) and paxilline on action potential firing were sensitive to resveratrol. Our results indicated that the attenuation of action potential firing rate by resveratrol might be mediated through opening the BK_Ca channels and closing the voltage-gated sodium channels.

Conclusions

As BK_Ca channels and sodium channels are critical molecular determinants for seizure generation, our findings suggest that regulation of these two channels in cortical neurons probably makes a considerable contribution to the antiseizure activity of resveratrol.

Antioxidant effects of resveratrol in the cardiovascular system

The antioxidant effects of resveratrol (3,5,4'-trihydroxy-trans-stilbene) contribute substantially to the health benefits of this compound. Resveratrol has been shown to be a scavenger of a number of free radicals. However, the direct scavenging activities of resveratrol are relatively poor. The antioxidant properties of resveratrol in vivo are more likely to be attributable to its effect as a gene regulator. Resveratrol inhibits NADPH oxidase-mediated production of ROS by down-regulating the expression and activity of the oxidase. This polyphenolic compound reduces mitochondrial superoxide generation by stimulating mitochondria biogenesis. Resveratrol prevents superoxide production from uncoupled endothelial nitric oxide synthase by up-regulating the tetrahydrobiopterin-synthesizing enzyme GTP cyclohydrolase I. In addition, resveratrol increases the expression of various antioxidant enzymes. Some of the gene-regulating effects of resveratrol are mediated by the histone/protein deacetylase sirtuin 1 or by the nuclear factor-E2-related factor-2. In this review article, we have also summarized the cardiovascular effects of resveratrol observed in clinical trials.

LINKED ARTICLES

This article is part of a themed section on Redox Biology and Oxidative Stress in Health and Disease. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.12/issuetoc.

Ovarian actions of resveratrol

Resveratrol, a natural polyphenol found in grapes, berries, and medicinal plants, exhibits antioxidant and anti-inflammatory activities and has been proposed to be a longevity-prolonging agent. There is also growing evidence that resveratrol has cardioprotective properties and beneficial effects on both glucose and lipid metabolism. Recently, several studies have examined the use of resveratrol as a therapeutic agent to treat numerous pathological and metabolic disorders. Herein, we present insights into the mechanisms of action, biological effects, and current evidence of actions of resveratrol on the ovary. In vitro, resveratrol inhibits proliferation and androgen production by theca-interstitial cells. Resveratrol also exerts a cytostatic, but not cytotoxic, effect on granulosa cells, while decreasing aromatization and vascular endothelial growth factor expression. In vivo, resveratrol treatment reduced the size of adipocytes and improved estrus cyclicity in the previously acyclic rat model of polycystic ovary syndrome (PCOS). In addition, resveratrol increased the ovarian follicular reserve and prolonged the ovarian life span in rats. Taken together, resveratrol emerges as a potential therapeutic agent to treat conditions associated with androgen excess, such as PCOS. The efficacy of resveratrol in the treatment of gynecological conditions requires further investigation.

Modulation of Hypercholesterolemia-Induced Oxidative/Nitrative Stress in the Heart

Hypercholesterolemia is a frequent metabolic disorder associated with increased risk for cardiovascular morbidity and mortality. In addition to its well-known proatherogenic effect, hypercholesterolemia may exert direct effects on the myocardium resulting in contractile dysfunction, aggravated ischemia/reperfusion injury, and diminished stress adaptation. Both preclinical and clinical studies suggested that elevated oxidative and/or nitrative stress plays a key role in cardiac complications induced by hypercholesterolemia. Therefore, modulation of hypercholesterolemia-induced myocardial oxidative/nitrative stress is a feasible approach to prevent or treat deleterious cardiac consequences. In this review, we discuss the effects of various pharmaceuticals, nutraceuticals, some novel potential pharmacological approaches, and physical exercise on hypercholesterolemia-induced oxidative/nitrative stress and subsequent cardiac dysfunction as well as impaired ischemic stress adaptation of the heart in hypercholesterolemia.

Resveratrol protects against diet-induced atherosclerosis by reducing low-density lipoprotein cholesterol and inhibiting inflammation in apolipoprotein E-deficient mice

OBJECTIVES

Resveratrol (RES) is a polyphenol compound that has been shown a promising cardioprotective effect. However, some reports have yielded conflicting findings. Herein, we investigated the anti-atherosclerotic effects of RES in apolipoprotein E (apo E)-deficient mice on a high cholesterol diet.

MATERIALS AND METHODS

Firstly, atherosclerosis was induced by feeding a high cholesterol diet to apo E-deficient mice. Then, we examined its effects on weight control, and serum interleukin-6 (IL-6) levels and used histopathological methods to analyze morphology and inflammatory marker of atherosclerotic lesions in mice orally supplemented with high (25 mg/kg/day) and low (5 mg/kg/day) doses of RES for 8 weeks.

RESULTS

Mice with high dose of RES had reduced epididymal fat pads, and lower serum IL-6 levels compared with those of control mice. Moreover, RES in high doses also decreased the low-density lipoprotein cholesterol (LDL-C) levels and atherogenic index (LDL-C/HDL-C) in the mice. Dissection of high-dose RES-treated mice revealed a marked reduction in fat deposition, percentage of mice with atherosclerotic lesion, and intima/media ratio in the aortic areas. The expressions of macrophage-specific marker F4/80 and cardiovascular inflammatory marker NF-κB in atherosclerotic vessels were both diminished in the atherosclerotic vessels of high-dose RES-supplementated apo E-deficient mice.

CONCLUSION

These results suggest that RES prevented the effects of a high cholesterol diet on the rate of accretion in atherosclerosis progression by reducing the LDL-C levels and suppressing atherosclerotic inflammation. RES can therefore be valuable in the development of new anti-atherosclerotic agents.

Resveratrol and anti-atherogenic effects

The role of inflammation and oxidative stress in atherosclerosis development has been increasingly well recognized over the past decade. Inflammation has a significant role at all stages of atherosclerosis, including initiation, progression and plaque formation. Resveratrol is a naturally occurring polyphenolic compound found in grape products, berry fruits and red wine. Its ability to behave therapeutically as a component of red wine has attracted wide attention. Accumulating evidence suggests that it is a highly pleiotropic molecule that modulates numerous targets and molecular functions. Epidemiological studies indicate that the Mediterranean diet, rich in resveratrol, is associated with a reduced risk of atherosclerosis. Resveratrol is believed to decrease circulating low-density lipoprotein cholesterol levels, reduce cardiovascular disease risk; it reduces lipid peroxidation, platelet aggregation and oxidative stress. Resveratrol is considered a safe compound, since no significant toxic effects have been demonstrated after administration of a broad range of concentrations, and an effective anti-atherogenic agent.

An overview of the efficacy of resveratrol in the management of ischemic heart disease

Ischemic heart disease is a leading cause of cardiac dysfunction and subsequent morbidity and mortality around the world. New therapies are required to complement or enhance the existing treatment regimen for the management of ischemic heart disease-related clinical complications. In this regard, compounds derived from natural sources have recently gained attention for their cardioprotective properties. In particular, the potential of food-derived compounds that exhibit medicinal properties (termed nutraceuticals) appears promising, an example being the plant polyphenol resveratrol. In the past two decades, many preclinical and a few pilot clinical studies have shown that resveratrol is beneficial in protecting against cardiovascular disease. In this short review, we will discuss current evidence on the efficacy of resveratrol in preventing or reversing deleterious effects on the heart in the setting of ischemic heart disease.

Polydatin: a new therapeutic agent against multiorgan dysfunction

BACKGROUND

Polydatin (PD), a monocrystalline and polyphenolic drug isolated from a traditional Chinese herb (Polygonum cuspidatum), is protective against mitochondrial dysfunction and has been approved for clinical trials in the treatment of shock. However, whether the administration of PD has a therapeutic effect on multiple-organ dysfunction syndrome (MODS) requires investigation.

MATERIAL AND METHODS

MODS was induced in Sprague-Dawley rats via hemorrhage and ligation and puncture of cecum-induced sepsis. The rats were divided into three groups as follows: MODS + PD, MODS + normal saline, and a control group (no treatment). Survival time, blood biochemical indexes, and histopathologic changes in various organs were evaluated; serum oxidative stress (advanced oxidative protein products [AOPPs]) and proinflammatory cytokines (tumor necrosis factor-α, interleukin 1β, and interleukin 6) were assayed using enzyme-linked immunosorbent assay. Apoptosis-related protein expression (B-cell lymphoma-2 [Bcl-2] and Bax) was assayed by immunohistochemical and Western blotting methods, whereas caspase-3 activity was assayed by spectrophotometry.

RESULTS

PD improved organ function, prolonged survival time, and reduced MODS incidence and serum levels of AOPPs and proinflammatory cytokines. It also decreased Bax levels and caspase-3 activity and increased Bcl-2 levels in the kidney and liver.

CONCLUSIONS

PD may serve as a potential therapeutic for MODS, as it suppresses oxidative stress, inhibits inflammatory response, attenuates apoptosis, and protects against mitochondrial dysfunction.

Effect of atorvastatin on serum oxidative stress and N-terminal brain natriuretic peptide expression in rats

OBJECTIVE

To investigate the effect of atorvastatin on serum oxidative stress and N-terminal brain natriuretic peptide expression in rats.

METHODS

A total of 40 healthy male SD rats were randomly divided into the sham group (Group A, n=10, saline 5 mL/d), ischemia-reperfusion group (Group B, n=10, saline 5 mL/d), atorvastatin group (Group C, n=10, atorvastatin 20 mg/kg · d), atorvastatin + N-amino-arginine group (Group D, n=10, atorvastatin 20 mg/kg · d + N-amino arginine 15 mg/kg). Myocardial ischemia-reperfusion rat model was established after 3 days of gavage. N-amino arginine 15 mg/kg was given by tail vein injection 15 min before ischemia. After reperfusion, enzymology indicators such us creatine kinase (CK) and lactate dehydrogenase and the oxidative stress parameters such as nitric oxide (NO), malondialdehyde (MDA) and total superoxide dismutase (TSOD), and n-terminal pro-brain natriuretic peptide (NT-proBNP) expression was detected by immunohistochemistry.

RESULTS

LDH and CK levels of group A were significantly lower than the other three groups, and group B was the highest. There was significant difference between group B and group C (P<0.05), and no significant difference between group B and group D (P>0.05). MDA levels in group B were significantly higher than the other three groups. The lowest was group A, followed by group C, the difference among groups was significantly (P<0.05). TSOD and NO levels in group B was the lowest, the level in group A was the highest, followed by group C, the difference among groups was significant (P<0.05). NT-proBNP level in group B was significantly higher than the other three groups, the lowest was group A, followed by group C, the difference among groups was significant (P<0.05).

CONCLUSIONS

Atorvastatin has a protective effect on the myocardial injury in the myocardial ischemia and reperfusion rats. It can increase NO synthesis and decrease MDA content, increase serum TSOD activity and the oxidative stress effect, meanwhile protect myocardial cells and reduce myocardial injury.