Antioxidants in Cardiovascular Therapy: Panacea or False Hope?

Anti-atherogenic role of green tea (Camellia sinensis) in South Indian smokers

ETHNOPHARMACOLOGICAL RELEVANCE

Green tea (Camellia sinensis) is a popular beverage consumed all over the world due to its health benefits. Many of these beneficial effects of green tea are attributed to polyphenols, particularly catechins.

AIM OF THE STUDY

The present study focuses on underlying anti-platelet aggregation, anti-thrombotic, and anti-lipidemic molecular mechanisms of green tea in South Indian smokers.

MATERIALS AND METHODS

We selected 120 South Indian male volunteers for this study to collect the blood and categorised them into four groups; control group individuals (Controls), smokers, healthy control individuals consuming green tea, and smokers consuming green tea. Smokers group subjects have been smoking an average 16-18 cigarettes per day for the last 7 years or more. The subjects (green tea consumed groups) consumed 100 mL of green tea each time, thrice a day for a one-year period.

RESULTS

LC-MS analysis revealed the presence of multiple phytocompounds along with catechins in green tea extract. Increased plasma lipid peroxidation (LPO), protein carbonyls, cholesterol, triglycerides, and LDL-cholesterol with decreased HDL-cholesterol levels were observed in smokers compared to the control group and the consumption of green tea showed beneficial effect. Furthermore, docking studies revealed that natural compounds of green tea had high binding capacity with 3-hydroxy-3-methyl-glutaryl-CoA reductase (HMG-CoA) when compared to their positive controls, whereas (-) epigallocatechin-3-gallate (EGCG) and (-) epicatechin-gallate (ECG) had high binding capacity with sterol regulatory element-binding transcription factor 1 (SREBP1c). Further, our ex vivo studies showed that green tea extract (GTE) significantly inhibited platelet aggregation and increased thrombolytic activity in a dose dependent manner.

CONCLUSION

In conclusion, in smokers, catechins synergistically lowered oxidative stress, platelet aggregation and modified the aberrant lipid profile. Furthermore, molecular docking studies supported green tea catechins' antihyperlipidemic efficacy through strong inhibitory activity on HMG-CoA reductase and SREBP1c. The mitigating effects of green tea on cardiovascular disease risk factors in smokers that have been reported can be attributed majorly to catechins or to their synergistic effects.

Sulfur metabolism as a new therapeutic target of heart failure

Sulfur-based redox signaling has long attracted attention as critical mechanisms underlying the development of cardiac diseases and resultant heart failure. Especially, post-translational modifications of cysteine (Cys) thiols in proteins mediate oxidative stress-dependent cardiac remodeling including myocardial hypertrophy, senescence, and interstitial fibrosis. However, we recently revealed the existence of Cys persulfides and Cys polysulfides in cells and tissues, which show higher redox activities than Cys and substantially contribute to redox signaling and energy metabolism. We have established simple evaluation methods that can detect polysulfides in proteins and inorganic polysulfides in cells and revealed that polysulfides abundantly expressed in normal hearts are dramatically catabolized by exposure to ischemic/hypoxic and environmental electrophilic stress, which causes vulnerability of the heart to mechanical load. Accumulation of hydrogen sulfide, a nucleophilic catabolite of persulfides/polysulfides, may lead to reductive stress in ischemic hearts, and perturbation of polysulfide catabolism can improve chronic heart failure after myocardial infarction in mice. This review focuses on the (patho)physiological role of sulfur metabolism in hearts, and proposes that sulfur catabolism during ischemic/hypoxic stress has great potential as a new therapeutic strategy for the treatment of ischemic heart failure.

Effectiveness of anthocyanin-containing foods and nutraceuticals in mitigating oxidative stress, inflammation, and cardiovascular health-related biomarkers: a systematic review of animal and human interventions

Cardiovascular diseases (CVDs) are a group of chronic health disorders prevalent worldwide that claim millions of lives yearly. Inflammation and oxidative stress are intricately associated with myocardial tissue damage, endothelial dysfunction, and increased odds of heart failure. Thus, dietary strategies aimed at decreasing the odds of CVDs are paramount. In this regard, the consumption of anthocyanins, natural pigments found in edible flowers, fruits, and vegetables, has attracted attention due to their potential to promote cardiovascular health. The main mechanisms of action linked with their protective effects on antioxidant and anti-inflammatory activities, serum lipid profile modulation, and other cardiovascular health parameters are explained and exemplified. However, little is known about the dose-dependency nature of the effects, which anthocyanin has better efficiency, and whether anthocyanin-containing foods display better in vivo efficacy than nutraceuticals (i.e., concentrated extracts containing higher levels of anthocyanins than foods). Thus, this systematic review focused on determining the effects of anthocyanin-containing foods and nutraceuticals on biomarkers associated with CVDs using animal studies and human interventions supported by in vitro mechanistic insights. Overall, the results showed that the regular consumption of anthocyanin-containing foods and nutraceuticals improved vascular function, lipid profile, and antioxidant and anti-inflammatory effects. The daily dosage, the participants' health status, and the duration of the intervention also significantly influenced the results.

Melatonin Use during Pregnancy and Lactation Complicated by Oxidative Stress: Focus on Offspring's Cardiovascular-Kidney-Metabolic Health in Animal Models

Cardiovascular-kidney-metabolic (CKM) syndrome has emerged as a major global public health concern, posing a substantial threat to human health. Early-life exposure to oxidative stress may heighten vulnerability to the developmental programming of adult diseases, encompassing various aspects of CKM syndrome. Conversely, the initiation of adverse programming processes can potentially be thwarted through early-life antioxidant interventions. Melatonin, originally recognized for its antioxidant properties, is an endogenous hormone with diverse biological functions. While melatonin has demonstrated benefits in addressing disorders linked to oxidative stress, there has been comparatively less focus on investigating its reprogramming effects on CKM syndrome. This review consolidates the current knowledge on the role of oxidative stress during pregnancy and lactation in inducing CKM traits in offspring, emphasizing the underlying mechanisms. The multifaceted role of melatonin in regulating oxidative stress, mediating fetal programming, and preventing adverse outcomes in offspring positions it as a promising reprogramming strategy. Currently, there is a lack of sufficient information in humans, and the available evidence primarily originates from animal studies. This opens up new avenues for novel preventive intervention in CKM syndrome.

Cardiovascular aging: spotlight on mitochondria

Mitochondria are cellular organelles critical for ATP production and are particularly relevant to cardiovascular diseases including heart failure, atherosclerosis, ischemia-reperfusion injury, and cardiomyopathies. With advancing age, even in the absence of clinical disease, mitochondrial homeostasis becomes disrupted (e.g., redox balance, mitochondrial DNA damage, oxidative metabolism, and mitochondrial quality control). Mitochondrial dysregulation leads to the accumulation of damaged and dysfunctional mitochondria, producing excessive reactive oxygen species and perpetuating mitochondrial dysfunction. In addition, mitochondrial DNA, cardiolipin, and N-formyl peptides are potent activators of cell-intrinsic and -extrinsic inflammatory pathways. These age-related mitochondrial changes contribute to the development of cardiovascular diseases. This review covers the impact of aging on mitochondria and links these mechanisms to therapeutic implications for age-associated cardiovascular diseases.

Cardioprotective role of a magnolol and honokiol complex in the prevention of doxorubicin-mediated cardiotoxicity in adult rats

Doxorubicin (DOXO) induces marked cardiotoxicity, though increased oxidative stress while there are some documents related with cardioprotective effects of some antioxidants against organ-toxicity during cancer treatment. Although magnolia bark has some antioxidant-like effects, its action in DOXO-induced heart dysfunction has not be shown clearly. Therefore, here, we aimed to investigate the cardioprotective action of a magnolia bark extract with active component magnolol and honokiol complex (MAHOC; 100 mg/kg) in DOXO-treated rat hearts. One group of adult male Wistar rats was injected with DOXO (DOXO-group; a cumulative dose of 15 mg/kg in 2-week) or saline (CON-group). One group of DOXO-treated rats was administered with MAHOC before DOXO (Pre-MAHOC group; 2-week) while another group was administered with MAHOC following the 2-week DOXO (Post-MAHOC group). MAHOC administration, before or after DOXO, provided full survival of animals during 12-14 weeks, and significant recoveries in the systemic parameters of animals such as plasma levels of manganese and zinc, total oxidant and antioxidant statuses, and also systolic and diastolic blood pressures. This treatment also significantly improved heart function including recoveries in end-diastolic volume, left ventricular end-systolic volume, heart rate, cardiac output, and prolonged P-wave duration. Furthermore, the MAHOC administrations improved the structure of left ventricles such as recoveries in loss of myofibrils, degenerative nuclear changes, fragmentation of cardiomyocytes, and interstitial edema. Biochemical analysis in the heart tissues provided the important cardioprotective effect of MAHOC on the redox regulation of the heart, such as improvements in activities of glutathione peroxidase and glutathione reductase, and oxygen radical-absorbing capacity of the heart together with recoveries in other systemic parameters of animals, while all of these benefits were observed in the Pre-MAHOC treatment group, more prominently. Overall, one can point out the beneficial antioxidant effects of MAHOC in chronic heart diseases as a supporting and complementing agent to the conventional therapies.

Oxidative balance score was negatively associated with the risk of metabolic syndrome, metabolic syndrome severity, and all-cause mortality of patients with metabolic syndrome

Background

The oxidative balance score (OBS), an encompassing scoring mechanism for assessing oxidative stress, is formulated based on nutritional and lifestyle components. The emergence of metabolic syndrome (MetS) is intricately linked to oxidative stress. Nonetheless, the correlation between OBS and MetS displays variability within distinct cohorts.

Objective

We worked on the relationships between OBS and the risk of MetS, MetS severity, and all-cause mortality of MetS patients.

Methods

A total of 11,171 adult participants were collected from the U.S. National Health Examination Survey (NHANES) 2007-2018. Employing survey-weighted logistic models, we evaluated the relationship between OBS and MetS risk. Furthermore, survey-weighted linear models were utilized to investigate the connection between OBS and MetS severity. Among the participants, 3,621 individuals had their survival status recorded, allowing us to employ Cox proportional hazards regression models in order to ascertain the association between OBS and the all-cause mortality within the subset of individuals with MetS. The OBS (where a higher OBS signified an increased prevalence of anti- or pro-oxidant exposures) weighed the 20 factors, while the MetS severity score weighed the five factors.

Results

After multivariable adjustment, individuals with elevated OBS were found to exhibit a decreased susceptibility to MetS [odds ratio (OR) 0.95; 95% CI 0.94-0.96]. The adjusted OR was 0.42 (95% CI 0.33-0.53) for MetS risk in the fourth OBS quartile compared with those in the first OBS quartile (P for trend < 0.001). A one-unit increase in OBS was linked to a 3% reduction in MetS severity score by 3% (mean difference, -0.03; 95% CI, -0.04 to -0.03). Moreover, increased OBS correlated with decreased hazard of all-cause mortality risk among MetS subjects (adjusted hazard ratio, 0.95; 95% CI, 0.93-0.98). These associations retained their strength even subsequent to the introduction of sensitivity analyses. There existed a statistically significant negative correlation between diet/lifestyle OBS and both MetS risk as well as MetS severity.

Conclusions

An inverse correlation was observed between OBS and the susceptibility to MetS, MetS severity, and all-cause mortality of MetS patients. Health outcomes for MetS patients were positively related to antioxidant diets and lifestyles.

Biomaterials-Based Antioxidant Strategies for the Treatment of Oxidative Stress Diseases

Oxidative stress is characterized by an increase in reactive oxygen species or a decrease in antioxidants in the body. This imbalance leads to detrimental effects, including inflammation and multiple chronic diseases, ranging from impaired wound healing to highly impacting pathologies in the neural and cardiovascular systems, or the bone, amongst others. However, supplying compounds with antioxidant activity is hampered by their low bioavailability. The development of biomaterials with antioxidant capacity is poised to overcome this roadblock. Moreover, in the treatment of chronic inflammation, material-based strategies would allow the controlled and targeted release of antioxidants into the affected tissue. In this review, we revise the main causes and effects of oxidative stress, and survey antioxidant biomaterials used for the treatment of chronic wounds, neurodegenerative diseases, cardiovascular diseases (focusing on cardiac infarction, myocardial ischemia-reperfusion injury and atherosclerosis) and osteoporosis. We anticipate that these developments will lead to the emergence of new technologies for tissue engineering, control of oxidative stress and prevention of diseases associated with oxidative stress.

Severe fever with thrombocytopenia syndrome virus induces platelet activation and apoptosis via a reactive oxygen species-dependent pathway

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging tick-borne infectious disease caused by the SFTS virus (SFTSV) and with a high fatality rate. Thrombocytopenia is a major clinical manifestation observed in SFTS patients, but the underlying mechanism remains largely unclear. Here, we explored the effects of SFTSV infection on platelet function in vivo in severely infected SFTSV IFNar-/- mice and on mouse and human platelet function in vitro. Results showed that SFTSV-induced platelet clearance acceleration may be the main reason for thrombocytopenia. SFTSV-potentiated platelet activation and apoptosis were also observed in infected mice. Further investigation showed that SFTSV infection induced platelet reactive oxygen species (ROS) production and mitochondrial dysfunction. In vitro experiments revealed that administration of SFTSV or SFTSV glycoprotein (Gn) increased activation, apoptosis, ROS production, and mitochondrial dysfunction in separated mouse platelets, which could be effectively ameliorated by the application of antioxidants (NAC (N-acetyl-l-cysteine), SKQ1 (10-(6'-plastoquinonyl) decyltriphenylphosphonium) and resveratrol). In vivo experiments showed that the antioxidants partially rescued SFTSV infection-induced thrombocytopenia by improving excessive ROS production and mitochondrial dysfunction and down-regulating platelet apoptosis and activation. Furthermore, while SFTSV and Gn directly potentiated human platelet activation, it was completely abolished by antioxidants. This study revealed that SFTSV and Gn can directly trigger platelet activation and apoptosis in an ROS-MAPK-dependent manner, which may contribute to thrombocytopenia and hemorrhage during infection, but can be abolished by antioxidants.

Dimethyl fumarate possesses antiplatelet and antithrombotic properties

BACKGROUND

Dimethyl fumarate (DMF) is a methyl ester of fumaric acid and has been approved for treating multiple sclerosis (MS) and psoriasis due to anti-inflammatory effect. There is a close association between platelets and the pathogenesis of MS. Whether DMF affects platelet function remains unclear. Our study intends to evaluate DMF's effect on platelet function.

METHODS

Washed human platelets were treated with different concentrations of DMF (0, 50, 100 and 200 μM) at 37 °C for 1 h followed by analysis of platelet aggregation, granules release, receptors expression, spreading and clot retraction. In addition, mice received intraperitoneal injection of DMF (15 mg/kg) to assess tail bleeding time, arterial and venous thrombosis.

RESULTS

DMF significantly inhibited platelet aggregation and the release of dense/alpha granules in response to collagen-related peptide (CRP) or thrombin stimulation dose-dependently without altering the expression of platelet receptors α_IIbβ3, GPIbα, and GPVI. In addition, DMF-treated platelets presented significantly reduced spreading on collagen or fibrinogen and thrombin-mediated clot retraction along with the decreased phosphorylation of c-Src and PLCγ2. Moreover, administration of DMF into mice significantly prolonged the tail bleeding time and impaired arterial and venous thrombus formation. Furthermore, DMF reduced the generation of intracellular reactive oxygen species and calcium mobilization, and inhibited NF-κB activation and the phosphorylation of ERK1/2, p38 and AKT.

CONCLUSION

DMF inhibits platelet function and arterial/venous thrombus formation. Considering the presence of thrombotic events in MS, our study indicates that DMF treatment for patients with MS might obtain both anti-inflammatory and anti-thrombotic benefits.

Effect of Vitamin E on Apoptosis of the Endothelial Cells of the Carotid Arteries in Hypercholesterolemic Male Rabbits

INTRODUCTION

Cardiovascular disease is the principal cause of mortality and morbidity in developed countries, leading to the formation of atherosclerosis plaques and thrombosis. Apoptosis of endothelial cells is one of the primary factors in vascular thrombosis. Lipids, when oxidized by endothelial cells, result in an increased thickness of the arterial wall. Iron is also recognized as an atherogenic element that induces atherosclerosis. There remains uncertainty about the antioxidative role of vitamin E in the formation of atherosclerosis. In this study, the authors evaluated the effect of iron and vitamin E on the apoptosis of endothelial cells in the carotid arteries of hypercholesterolemic male rabbits.

METHOD

Thirty white male rabbits were randomly divided into five groups and fed the following diet for six weeks: Group 1: control, Group 2: cholesterol (1%), Group 3: cholesterol (1%) + vitamin E (50 mg/kg), Group 4: cholesterol (1%) + Iron (50 mg/kg), and Group 5: cholesterol (1%) + vitamin E (50 mg/kg) + Iron (50 mg/kg). Serum cholesterol, TG, HDL, and LDL levels were assessed after six weeks. Finally, the animals were sacrificed with ketamine, and carotid arteries were removed. The samples were fixed in 10% formalin, and TUNEL staining was used after the tissue processing. Cell counts were carried out under a light microscope.

RESULTS

Vitamin E decreased Serum cholesterol and apoptotic endothelial cells in the hypercholesterolemic + vitamin E diet (P< 0.05). However, they increased significantly in the interference groups compared to the control group (P< 0.05).

CONCLUSION

According to our findings, vitamin E showed to have a beneficial effect on preventing cardiovascular diseases and may play a positive role in the prevention of atherosclerosis.

Outlook on Chronic Venous Disease Treatment: Phytochemical Screening, In Vitro Antioxidant Activity and In Silico Studies for Three Vegetal Extracts

Chronic venous disease is one of the most common vascular diseases; the signs and symptoms are varied and are often neglected in the early stages. Vascular damage is based on proinflammatory, prothrombotic, prooxidant activity and increased expression of several matrix metalloproteinases (MMPs). The aim of this research is preparation and preliminary characterization of three vegetal extracts (Sophorae flos-SE, Ginkgo bilobae folium-GE and Calendulae flos-CE). The obtained dry extracts were subjected to phytochemical screening (FT-ICR-MS, UHPLC-HRMS/MS) and quantitative analysis (UHPLC-HRMS/MS, spectrophotometric methods). Antioxidant activity was evaluated using three methods: FRAP, DPPH and ABTS. More than 30 compounds were found in each extract. The amount of flavones follows the succession: SE > GE > CE; the amount of phenolcarboxylic acids follows: SE > CE > GE; and the amount of polyphenols follows: SE > GE > CE. Results for FRAP method varied as follows: SE > CE > GE; results for the DPPH method followed: SE > GE > CE; and results for ABTS followed: SE > GE > CE. Strong and very strong correlations (appreciated by Pearson coefficient) have been observed between antioxidant activity and the chemical content of extracts. Molecular docking studies revealed the potential of several identified phytochemicals to inhibit the activity of four MMP isoforms. In conclusion, these three extracts have potential in the treatment of chronic venous disease, based on their phytochemical composition.

Endothelial dysfunction due to eNOS uncoupling: molecular mechanisms as potential therapeutic targets

Nitric oxide (NO) is one of the most important molecules released by endothelial cells, and its antiatherogenic properties support cardiovascular homeostasis. Diminished NO bioavailability is a common hallmark of endothelial dysfunction underlying the pathogenesis of the cardiovascular disease. Vascular NO is synthesized by endothelial nitric oxide synthase (eNOS) from the substrate L-arginine (L-Arg), with tetrahydrobiopterin (BH₄) as an essential cofactor. Cardiovascular risk factors such as diabetes, dyslipidemia, hypertension, aging, or smoking increase vascular oxidative stress that strongly affects eNOS activity and leads to eNOS uncoupling. Uncoupled eNOS produces superoxide anion (O₂^-) instead of NO, thus becoming a source of harmful free radicals exacerbating the oxidative stress further. eNOS uncoupling is thought to be one of the major underlying causes of endothelial dysfunction observed in the pathogenesis of vascular diseases. Here, we discuss the main mechanisms of eNOS uncoupling, including oxidative depletion of the critical eNOS cofactor BH₄, deficiency of eNOS substrate L-Arg, or accumulation of its analog asymmetrical dimethylarginine (ADMA), and eNOS S-glutathionylation. Moreover, potential therapeutic approaches that prevent eNOS uncoupling by improving cofactor availability, restoration of L-Arg/ADMA ratio, or modulation of eNOS S-glutathionylation are briefly outlined.

Ascorbic acid attenuates cadmium-induced myocardial hypertrophy and cardiomyocyte injury through Nrf2 signaling pathways comparable to resveratrol

Chronic cadmium (Cd) exposure severely affects the structural integrity of the heart, leading to cardiovascular disease. This study investigates the protective role of ascorbic acid (AA) and resveratrol (Res) in cellular defense against Cd-induced cardiomyocyte damage and myocardial hypertrophy in H9c2 cardiomyocytes. Experimental results showed that AA and Res treatment significantly increased cell viability, reduced ROS production, attenuated lipid peroxidation, and increased antioxidant enzyme activity in Cd-induced H9c2 cells. AA and Res decreased the mitochondrial membrane permeability and protected the cells from Cd induced cardiomyocyte damage. This also suppressed the pathological hypertrophic response triggered by Cd, which increased the cell size of cardiomyocytes. Gene expression studies revealed that cells treated with AA and Res decreased the expression of hypertrophic genes ANP (two-fold), BNP (one-fold) and β- MHC (two-fold) compared to Cd exposed cells. AA and Res promoted the nuclear translocation of Nrf2 and increased the expression of antioxidant genes (HO-1, NQO1, SOD and CAT) during Cd mediated myocardial hypertrophy. This study proves that AA and Res play a significant role in improving Nrf2 signaling, thereby reversing stress-induced injury, and facilitating the regression of myocardial hypertrophy.

Lycopene abolishes palmitate-mediated myocardial inflammation in female Wistar rats via modulation of lipid metabolism, NF-κB signalling pathway, and augmenting the antioxidant systems

BACKGROUND AND AIMS

Obesity-related heart failure is exacerbated by excessive intake of saturated fats such as palmitate (PA). Lycopene (LYC) possesses anti-lipidemic, antioxidant, cytoprotective, and anti-inflammatory effects. This study, therefore, evaluated the impact of LYC against PA-invoked cardiotoxicity.

METHODS AND RESULTS

Thirty-six female rats were equally divided into six groups: control; PA (5 mM); PA + LYC (24 mg/kg); PA + LYC (48 mg/kg); LYC (24 mg/kg); and LYC (48 mg/kg). The PA was administered five times weekly for seven weeks, while the LYC was given for the last two weeks. Lipids in the blood and the heart were estimated, as were oxidative stress and antioxidant indices, cardiac function, inflammation, and histology. Palmitate overload occasioned a significant (p < 0.05) increase in cardiac cholesterol (50%), phospholipids (19%), and non-esterified fatty acids (40%). However, triglyceride levels decreased (38%). Furthermore, malondialdehyde (45%), hydrogen peroxide (33%) levels and myeloperoxidase activity increased (79%). Also, cardiac gamma-glutamyl transferase (50%), serum creatine kinase activities (1.34 folds), NF-kB, interleukin1β, and interleukin-6 mRNA expression increased in the PA group relative to the control. In contrast, reduced glutathione (13%) and nitric oxide levels (22%), interleukin-10 mRNA expression, cardiac creatine kinase (35%), lactate dehydrogenase (33%), aspartate, and alanine transaminase activities decreased markedly (15- and 10%, respectively). Also, PA caused hyperemia, congestion of the cardiac interstitium, and infiltration of inflammatory cells. However, treatment with LYC reversed the features of cardiotoxicity and histological complications caused by PA. These observations are likely because LYC has anti-inflammatory, antioxidant, and cytoprotective properties.

CONCLUSION

Thus, LYC might be an appropriate remedy to manage PA-induced cardiotoxicity in female rats.

Natural flavonoids derived from herbal medicines are potential anti-atherogenic agents by inhibiting oxidative stress in endothelial cells

As the common pathological basis of various cardiovascular diseases, the morbidity and mortality of atherosclerosis (AS) have increased in recent years. Unfortunately, there are still many problems in the treatment of AS, and the prevention and treatment of the disease is not ideal. Up to now, the occurrence and development of AS can roughly include endothelial cell dysfunction, vascular smooth muscle cell proliferation, inflammation, foam cell production, and neoangiogenesis. Among them, endothelial dysfunction, as an early event of AS, plays a particularly important role in promoting the development of AS. In addition, oxidative stress occurs throughout the causes of endothelial dysfunction. Some previous studies have shown that flavonoids derived from herbal medicines are typical secondary metabolites. Due to its structural presence of multiple active hydroxyl groups, it is able to exert antioxidant activity in diseases. Therefore, in this review, we will search PubMed, Web of Science, Elesvier, Wliey, Springer for relevant literature, focusing on flavonoids extracted from herbal medicines, and summarizing how they can prevent endothelial dysfunction by inhibiting oxidative stress. Meanwhile, in our study, we found that flavonoid represented by quercetin and naringenin showed superior protective effects both in vivo and in vitro, suggesting the potential of flavonoid compounds in the treatment of AS.

Vasorelaxant Effect of Moroccan Cannabis sativa Threshing Residues on Rat Mesenteric Arterial Bed is Endothelium and Muscarinic Receptors Dependent

Introduction

Ethanolic fraction of Moroccan Cannabis sativa threshing residues (EFCS) was evaluated for its vasorelaxant activity. The current work aims to identify the active metabolites in the ethanolic fraction of the EFCS and illustrate their mechanism of action.

Methods

Free radical scavenging capacity of EFCS was assessed using DPPH method. The EFCS vasodilation activities in phenylephrine-precontracted isolated rat mesenteric arterial beds were investigated in presence of L-NAME (nitric oxide synthase inhibitor), indomethacin (cyclooxygenase inhibitor), potassium channel blockers (namely tetraetylamonium, barium chloride, and glibenclamide), and atropine. Nitric oxide vascular release was measured by electron paramagnetic resonance (EPR) using a spin trap in rat aortic rings.

Results

EFCS induced dose-dependent vasorelaxation on mesenteric vascular bed. Incubation of the preparations with L-NAME, ODQ (a soluble guanylyl cyclase inhibitor), or potassium channel blockers reduced the fall of perfusion pressure caused by EFCS. Endothelial denudation or atropine abolished the EFCS's vasorelaxant effect, suggesting involvement of muscarinic receptors and endothelium-relaxing factors. The extract induced nitric oxide release in aortic rings in a similar manner as acetylcholine suggesting an effect of EFCS on the muscarinic receptor and the conductance arteries. Chemical investigation of EFCS identified potential active components namely apigenin and derivatives of luteolin skeleton and also additional components such as neophytadiene, squalene, and β-sitosterol. In conclusion, the vasorelaxant effect of EFCS on rat mesenteric arterial bed, which is dependent of muscarinic receptor activation, nitric oxide, and EDHF, can account for potential therapeutic use against high blood pressure related cardiovascular diseases.

Metabolic Syndrome Programming and Reprogramming: Mechanistic Aspects of Oxidative Stress

Metabolic syndrome (MetS) is a worldwide public health issue characterized by a set of risk factors for cardiovascular disease. MetS can originate in early life by developmental programming. Increasing evidence suggests that oxidative stress, which is characterized as an imbalance between reactive oxygen species (ROS), nitric oxide (NO), and antioxidant systems, plays a decisive role in MetS programming. Results from human and animal studies indicate that maternal-derived insults induce MetS later in life, accompanied by oxidative stress programming of various organ systems. On the contrary, perinatal use of antioxidants can offset oxidative stress and thereby prevent MetS traits in adult offspring. This review provides an overview of current knowledge about the core mechanisms behind MetS programming, with particular focus on the occurrence of oxidative-stress-related pathogenesis as well as the use of potential oxidative-stress-targeted interventions as a reprogramming strategy to avert MetS of developmental origins. Future clinical studies should provide important proof of concept for the effectiveness of these reprogramming interventions to prevent a MetS epidemic.

Cytoprotective, antioxidant, and anti-migratory activity of Pistacia lentiscus L. supercritical carbon dioxide extract on primary human endothelial cells

Green chemistry is a useful tool for producing valuable chemicals from biomass. However, extracted compounds need to be tested for safety and efficacy before their use in humans. Here we investigate the chemical composition and biological effects of a leaves Pistacia lentiscus L. supercritical carbon dioxide (SCCO₂) extract. Terpenes represented the main extract fraction, with Germacrene D (11.18%), delta-cadinene (10.54%), and alpha-pinene (8.7%) the most abundant molecules. Challenged with endothelial cells (ECs), increasing extract concentrations failed to affect cell proliferation or promote cell toxicity. ROS assessment in unstressed and H₂O₂-treated ECs revealed an extract dose-dependent antioxidant activity. Exposition of H₂O₂-treated ECs to increasing extract concentrations dose-dependently counteracted H₂O₂-induced cell impairments. The extract significantly counteracted fetal calf serum-induced ECs migration. For the first time, we report that a SCCO₂ extract obtained from PL leaves is safe on ECs and may be a useful source of valuable compounds with vasculoprotective properties.

The Impact of Exercise on Redox Equilibrium in Cardiovascular Diseases

Cardiovascular diseases constitute the most important public health problem in the world. They are characterized by inflammation and oxidative stress in the heart and blood. Physical activity is recognized as one of the best ways to prevent these diseases, and it has already been applied in treatment. Physical exercise, both aerobic and anaerobic and single and multiple, is linked to the oxidant–antioxidant imbalance; however, this leads to positive adaptive changes in, among others, the increase in antioxidant capacity. The goal of the paper was to discuss the issue of redox equilibrium in the human organism in the course of cardiovascular diseases to systemize updated knowledge in the context of exercise impacts on the organism. Antioxidant supplementation is also an important issue since antioxidant supplements still have great potential regarding their use as drugs in these diseases.

Cardioprotective Effect of Acetylsalicylic Acid in the Myocardial Ischemia-Reperfusion Model on Oxidative Stress Markers Levels in Heart Muscle and Serum

Heart failure occurs in increased oxidative stress conditions, which contribute to the progression of pathological changes. Orally or intravenously administered acetylsalicylic acid (ASA, aspirin) is typically used in human patients with acute myocardial ischemia. The study used an experimental porcine ischemia-reperfusion model to evaluate the potential cardioprotective effect of intracoronary administered ASA on myocardial ischemia-reperfusion injury. The cardioprotective effect of ASA was evaluated by measuring selected oxidative stress markers levels in infarcted and non-infarcted myocardium 14 days after the procedure, and three times in serum, before the procedure, during the reperfusion process, and after 14-day recovery. The results showed that intracoronary administrated ASA reduced the oxidative stress. The level of oxidative stress, measured with the non-enzymatic markers total antioxidant capacity (TAC), total oxidative status (TOS), and malondialdehyde (MDA), and the enzymatic markers glutathione peroxidase (GPx), glutathione reductase (GR), and glutathione S-transferase (GST), in heart tissue was significantly higher in a control group injected with saline. The level of oxidative stress in serum, measured with TAC, TOS, oxidative stress index (OSI), and lipofuscin (LF), was also higher in the control group than in animals injected with ASA. The confirmed cardioprotective effect of intracoronary administered ASA provides the foundation for further studies on ASA intracoronary application, which may lead to the development of a new therapy for the treatment of ischemia-reperfusion complications in humans.

Butein Ameliorates Oxidative Stress in H9c2 Cardiomyoblasts through Activation of the NRF2 Signaling Pathway

Oxidative stress, defined as an imbalance between reactive oxygen species (ROS) production and the antioxidant defense system, contributes to the pathogenesis of many heart diseases. Therefore, oxidative stress has been highlighted as a therapeutic target for heart disease treatment. Butein, a tetrahydroxychalcone, has potential biological activities, especially antioxidant properties. However, the effect of butein on oxidative-stressed heart cells has been poorly studied. Thus, we sought to identify the antioxidant effects of butein in H9c2 cardiomyoblasts. To elucidate these antioxidant effects, various concentrations of butein were used to pretreat H9c2 cells prior to H₂O₂ treatment. Thereafter, measures of oxidative damages, such as ROS production, antioxidant expression levels, and apoptosis, were evaluated. Butein effectively increased cell viability and rescued the cells from oxidative damage through the inhibition of ROS production, apoptosis, and increased antioxidant expression. Furthermore, butein dramatically inhibited mitochondrial dysfunction and endoplasmic reticulum (ER) stress, which are the main ROS inducers. Nrf2 protein translocated from the cytosol to the nucleus and consequently activated its target genes as oxidative stress suppressors. These findings demonstrate that butein has potential antioxidant effects in H9c2 cardiomyoblasts, suggesting that it could be used as a therapeutic substance for the treatment of cardiac diseases.

Oxidative Stress and Antioxidant Therapy in Cardiovascular Diseases—Clinical Challenge

Oxidative stress reflects an imbalance between the production of reactive oxygen species (ROS) and the biological systems’ antioxidant mechanisms [...]

Biomarkers of Oxidative Stress Tethered to Cardiovascular Diseases

Cardiovascular disease (CVD) is a broad term that incorporated a group of conditions that affect the blood vessels and the heart. CVD is a foremost cause of fatalities around the world. Multiple pathophysiological mechanisms are involved in CVD; however, oxidative stress plays a vital role in generating reactive oxygen species (ROS). Oxidative stress occurs when the concentration of oxidants exceeds the potency of antioxidants within the body while producing reactive nitrogen species (RNS). ROS generated by oxidative stress disrupts cell signaling, DNA damage, lipids, and proteins, thereby resulting in inflammation and apoptosis. Mitochondria is the primary source of ROS production within cells. Increased ROS production reduces nitric oxide (NO) bioavailability, which elevates vasoconstriction within the arteries and contributes to the development of hypertension. ROS production has also been linked to the development of atherosclerotic plaque. Antioxidants can decrease oxidative stress in the body; however, various therapeutic drugs have been designed to treat oxidative stress damage due to CVD. The present review provides a detailed narrative of the oxidative stress and ROS generation with a primary focus on the oxidative stress biomarker and its association with CVD. We have also discussed the complex relationship between inflammation and endothelial dysfunction in CVD as well as oxidative stress-induced obesity in CVD. Finally, we discussed the role of antioxidants in reducing oxidative stress in CVD.

Protective Effect of Curcumin, Chrysin and Thymoquinone Injection on Trastuzumab-Induced Cardiotoxicity via Mitochondrial Protection

Mitochondrial dysfunction may lead to cardiomyocyte death in trastuzumab (TZM)-induced cardiotoxicity. Accordingly, this study was designed to evaluate the mitochondrial protective effects of curcumin, chrysin and thymoquinone alone in TZM-induced cardiotoxicity in the rats. Forty-eight male adult Wistar rats were divided into eight groups: control group (normal saline), TZM group (2.5 mg/kg I.P. injection, daily), TZM + curcumin group (10 mg/kg, I.P. injection, daily), TZM + chrysin (10 mg/kg, I.P. injection, daily), TZM + thymoquinone (0.5 mg/kg, I.P. injection, daily), curcumin group (10 mg/kg, I.P. injection, daily), chrysin group (10 mg/kg, I.P. injection, daily) and thymoquinone group (10 mg/kg, I.P. injection, daily). Blood and tissue were collected on day 11 and used for assessment of creatine phosphokinase, lactate dehydrogenase (LDH), troponin, malondialdehyde (MDA) amount, glutathione levels and mitochondrial toxicity parameters. TZM increased mitochondrial impairments (reactive oxygen species formation, mitochondrial swelling, mitochondrial membrane potential collapse and decline in succinate dehydrogenase activity) and histopathological alterations (hypertrophy, enlarged cell, disarrangement, myocytes degeneration, infiltration of fat in some areas, hemorrhage and focal vascular thrombosis) in rat heart. As well as TZM produced a significant increase in the level of CK, LDH, troponin, MDA, glutathione disulfide. In most experiments, the co-injection of curcumin, chrysin and thymoquinone with TZM restored the level of CK, LDH, troponin, MDA, GSH, mitochondrial impairments and histopathological alterations. The study revealed the cardioprotective effects of curcumin, chrysin and thymoquinone against TZM-induced cardiotoxicity which could be attributed to their antioxidant and mitochondrial protection activities.

Inhibition of HIF prolyl hydroxylase modulates platelet function

Hypoxia-inducible factors-1α (HIF-1α) involves in redox reaction. Considering the role of reactive oxygen species (ROS) in platelet function, whether it regulates platelet function remains unclear. Using an inhibitor of HIF prolyl hydroxylase IOX-2, we intend to investigate its effect on platelet function. Human platelets were treated with IOX-2 (0, 10, 25, and 50 M) followed by analysis of platelet aggregation, granule secretion, receptor expression, platelet spreading or clot retraction. Additionally, IOX-2 (10 mg/kg) was injected intraperitoneally into mice to measure tail bleeding time and arterial thrombosis. IOX-2 significantly inhibited collagen-related peptide (CRP, 0.25 μg/ml) or thrombin (0.03 U/ml)-induced platelet aggregation and ATP release dose dependently without affecting P-selectin expression and the surface levels of glycoprotein (GP)Ib, GPVI or IIb3. In addition, IOX-2-treated platelets presented significantly decreased spreading on fibrinogen or collagen and clot retraction. Moreover, IOX-2 administration into mice significantly impaired the in vivo hemostatic function of platelets and arterial thrombus formation without affecting the number of circulating platelets and coagulation factor (FVIII and FIX). Further, IOX-2 significantly upregulated HIF-1 in platelets, decreased ROS generation and downregulated NOX1 expression. Finally, IOX-2 increased the phosphorylation level of VASP (Ser157/239), and inhibited the phosphorylation of p38 (Thr180/Tyr182), ERK1/2 (Thr202/Tyr204), AKT (Thr308/Ser473) and PKC (Thr505) in CRP- or thrombin-stimulated platelets. In conclusion, inhibition of HIF prolyl hydroxylase modulates platelet function and arterial thrombus formation, possibly through upregulation of HIF-1α expression and subsequent inhibition of ROS generation, indicating that HIF-1α might be a novel target for the treatment of thrombotic disorders.

Coenzyme Q10 Reduces Infarct Size in Animal Models of Myocardial Ischemia-Reperfusion Injury: A Meta-Analysis and Summary of Underlying Mechanisms

Objective

Effective interventions that might limit myocardial ischemia-reperfusion (I/R) injury are still lacking. Coenzyme Q₁₀ (CoQ₁₀) may exert cardioprotective actions that reduce myocardial I/R injury. We conducted this meta-analysis to assess the potential cardioprotective effect of CoQ₁₀ in animal models of myocardial I/R injury.

Methods

We searched PubMed and Embase databases from inception to February 2022 to identify animal studies that compared the effect of CoQ₁₀ with vehicle treatment or no treatment on myocardial infarct size in models of myocardial I/R injury. Means and standard deviations of the infarct size measurements were pooled as the weighted mean difference with 95% confidence interval (CI) using the random-effects model. Subgroup analyses were also conducted according to animals' species, models' type, and reperfusion time.

Results

Six animal studies (4 in vivo and 2 ex vivo) with 116 animals were included. Pooled analysis suggested that CoQ₁₀ significantly reduced myocardial infarct size by −11.36% (95% CI: −16.82, −5.90, p < 0.0001, I² = 94%) compared with the control group. The significance of the pooled effect estimate was maintained in rats, Hartley guinea pigs, and Yorkshire pigs. However, it became insignificant in the subgroup of rabbits −5.29% (95% CI: −27.83, 17.26; I² = 87%). Furthermore, CoQ₁₀ significantly reduced the myocardial infarct size regardless of model type (either in vivo or ex vivo) and reperfusion time (either ≤ 4 h or >4 h).

Conclusion

Coenzyme Q₁₀ significantly decreased myocardial infarct size by 11.36% compared with the control group in animal models of myocardial I/R injury. This beneficial action was retained regardless of model type and reperfusion time.

Atherogenesis, Transcytosis, and the Transmural Cholesterol Flux: A Critical Review

The recently described phenomenon of cholesterol-loaded low-density lipoproteins (LDL) entering the arterial wall from the lumen by transcytosis has been accepted as an alternative for the long-held concept that atherogenesis involves only passive LDL movement across an injured or dysfunctional endothelial barrier. This active transport of LDL can now adequately explain why plaques (atheromas) appear under an intact, uninjured endothelium. However, the LDL transcytosis hypothesis is still questionable, mainly because the process serves no clear physiological purpose. Moreover, central components of the putative LDL transcytosis apparatus are shared by the counter process of cholesterol efflux and reverse cholesterol transport (RCT) and therefore can essentially create an energy-wasting futile cycle and paradoxically be pro- and antiatherogenic simultaneously. Hence, by critically reviewing the literature, we wish to put forward an alternative interpretation that, in our opinion, better fits the experimental evidence. We assert that most of the accumulating cholesterol (mainly as LDL) reaches the intima not from the lumen by transcytosis, but from the artery's inner layers: the adventitia and media. We have named this directional cholesterol transport transmural cholesterol flux (TCF). We suggest that excess cholesterol, diffusing from the avascular (i.e., devoid of blood and lymph vessels) media's smooth muscle cells, is cleared by the endothelium through its apical membrane. A plaque is formed when this cholesterol clearance rate lags behind its rate of arrival by TCF.

Targeting Reactive Oxygen Species in Atherosclerosis via Chinese Herbal Medicines

Cardio-cerebrovascular disease (CCVD) has become the leading cause of human mortality with the coming acceleration of global population aging. Atherosclerosis is among the most common pathological changes in CCVDs. It is also a multifactorial disorder; oxidative stress caused by excessive production of reactive oxygen species (ROS) has become an important mechanism of atherosclerosis. Chinese herbal medicine (CHM) is a major type of natural medicine that has made great contributions to human health. CHMs are increasingly used in the auxiliary clinical treatment of atherosclerosis. Although their mechanism of action is unclear, CHMs can exert a variety of antiatherosclerosis effects by regulating intracellular ROS. In this review, we discussed the mechanism of ROS regulation in atherosclerosis and analyzed the role of CHMs in the treatment of atherosclerosis via ROS.

Hyperoxia and Antioxidants for Myocardial Injury in Noncardiac Surgery: A 2 × 2 Factorial, Blinded, Randomized Clinical Trial

BACKGROUND

Hyperoxia and oxidative stress may be associated with increased risk of myocardial injury. The authors hypothesized that a perioperative inspiratory oxygen fraction of 0.80 versus 0.30 would increase the degree of myocardial injury within the first 3 days of surgery, and that an antioxidant intervention would reduce degree of myocardial injury versus placebo.

METHODS

A 2 × 2 factorial, randomized, blinded, multicenter trial enrolled patients older than 45 yr who had cardiovascular risk factors undergoing major noncardiac surgery. Factorial randomization allocated patients to one of two oxygen interventions from intubation and at 2 h after surgery, as well as antioxidant intervention or matching placebo. Antioxidants were 3 g IV vitamin C and 100 mg/kg N-acetylcysteine. The primary outcome was the degree of myocardial injury assessed by the area under the curve for high-sensitive troponin within the first 3 postoperative days.

RESULTS

The authors randomized 600 participants from April 2018 to January 2020 and analyzed 576 patients for the primary outcome. Baseline and intraoperative characteristics did not differ between groups. The primary outcome was 35 ng · day/l (19 to 58) in the 80% oxygen group; 35 ng · day/l (17 to 56) in the 30% oxygen group; 35 ng · day/l (19 to 54) in the antioxidants group; and 33 ng · day/l (18 to 57) in the placebo group. The median difference between oxygen groups was 1.5 ng · day/l (95% CI, -2.5 to 5.3; P = 0.202) and -0.5 ng · day/l (95% CI, -4.5 to 3.0; P = 0.228) between antioxidant groups. Mortality at 30 days occurred in 9 of 576 patients (1.6%; odds ratio, 2.01 [95% CI, 0.50 to 8.1]; P = 0.329 for the 80% vs. 30% oxygen groups; and odds ratio, 0.79 [95% CI, 0.214 to 2.99]; P = 0.732 for the antioxidants vs. placebo groups).

CONCLUSIONS

Perioperative interventions with high inspiratory oxygen fraction and antioxidants did not change the degree of myocardial injury within the first 3 days of surgery. This implies safety with 80% oxygen and no cardiovascular benefits of vitamin C and N-acetylcysteine in major noncardiac surgery.

EDITOR’S PERSPECTIVE

The Pathogenic Role of Foam Cells in Atherogenesis: Do They Represent Novel Therapeutic Targets?

BACKGROUND

Foam cells, mainly derived from monocytes-macrophages, contain lipid droplets essentially composed of cholesterol in their cytoplasm. They infiltrate the intima of arteries, contributing to the formation of atherosclerotic plaques.

PATHOGENESIS

Foam cells damage the arterial cell wall via the release of proinflammatory cytokines, free radicals, and matrix metalloproteinases, enhancing the plaque size up to its rupture.

THERAPY

A correct dietary regimen seems to be the most appropriate therapeutic approach to minimize obesity, which is associated with the formation of foam cells. At the same time, different types of antioxidants have been evaluated to arrest the formation of foam cells, even if the results are still contradictory. In any case, a combination of antioxidants seems to be more efficient in the prevention of atherosclerosis.

Therapeutic enzymes as non-conventional targets in cardiovascular impairments:A Comprehensive Review

Over the last few decades, substantial progress has been made towards the understanding of cardiovascular diseases (CVDs). In-depth mechanistic insights have also provided opportunities to explore novel therapeutic targets and treatment regimens to be discovered. Therapeutic enzymes are an example of such opportunities. The balanced functioning of such enzymes protects against a variety of CVDs while on the other hand, even a small shift in the normal functioning of these enzymes may lead to deleterious outcomes. Owing to the great versatility of these enzymes, inhibition and activation are key regulatory approaches to counter the onset and progression of several cardiovascular impairments. While cardiovascular remedies are already available in excess and of course they are efficacious, a comprehensive description of novel therapeutic enzymes to combat CVDs is the need of the hour. In light of this, the regulation of the functional activity of these enzymes also opens a new avenue for the treatment approaches to be employed. This review describes the importance of non-conventional enzymes as potential candidates in several cardiovascular disorders while highlighting some of the recently targeted therapeutic enzymes in CVDs.

Molecular Mechanisms of Possible Action of Phenolic Compounds in COVID-19 Protection and Prevention

The worldwide outbreak of COVID-19 was caused by a pathogenic virus called Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2). Therapies against SARS-CoV-2 target the virus or human cells or the immune system. However, therapies based on specific antibodies, such as vaccines and monoclonal antibodies, may become inefficient enough when the virus changes its antigenicity due to mutations. Polyphenols are the major class of bioactive compounds in nature, exerting diverse health effects based on their direct antioxidant activity and their effects in the modulation of intracellular signaling. There are currently numerous clinical trials investigating the effects of polyphenols in prophylaxis and the treatment of COVID-19, from symptomatic, via moderate and severe COVID-19 treatment, to anti-fibrotic treatment in discharged COVID-19 patients. Antiviral activities of polyphenols and their impact on immune system modulation could serve as a solid basis for developing polyphenol-based natural approaches for preventing and treating COVID-19.

Antioxidant properties of anthocyanins and their mechanism of action in atherosclerosis

Atherosclerosis develops due to lipid accumulation in the arterial wall and sclerosis as result of increased hyperlipidemia, oxidative stress, lipid oxidation, and protein oxidation. However, improving antioxidant status through diet may prevent the progression of atherosclerotic cardiovascular disease. It is believed that polyphenol-rich plants contribute to the inverse relationship between fruit and vegetable intake and chronic disease. Anthocyanins are flavonoid polyphenols with antioxidant properties that have been associated with reduced risk of cardiovascular disease. The consumption of anthocyanins increases total antioxidant capacity, antioxidant defense enzymes, and HDL antioxidant properties by several measures in preclinical and clinical populations. Anthocyanins appear to impart antioxidant actions via direct antioxidant properties, as well as indirectly via inducing intracellular Nrf2 activation and antioxidant gene expression. These actions counter oxidative stress and inflammatory signaling in cells present in atherosclerotic plaques, including macrophages and endothelial cells. Overall, anthocyanins may protect against atherosclerosis and cardiovascular disease through their effects on cellular antioxidant status, oxidative stress, and inflammation; however, their underlying mechanisms of action appear to be complex and require further elucidation.

Non-Transferrin-Bound Iron in the Spotlight: Novel Mechanistic Insights into the Vasculotoxic and Atherosclerotic Effect of Iron

Significance: While atherosclerosis is an almost inevitable consequence of aging, food preferences, lack of exercise, and other aspects of the lifestyle in many countries, the identification of new risk factors is of increasing importance to tackle a disease, which has become a major health burden for billions of people. Iron has long been suspected to promote the development of atherosclerosis, but data have been conflicting, and the contribution of iron is still debated controversially. Recent Advances: Several experimental and clinical studies have been recently published about this longstanding controversial problem, highlighting the critical need to unravel the complexity behind this topic. Critical Issues: The aim of the current review is to provide an overview of the current knowledge about the proatherosclerotic impact of iron, and discuss the emerging role of non-transferrin-bound iron (NTBI) as driver of vasculotoxicity and atherosclerosis. Finally, I will provide detailed mechanistic insights on the cellular processes and molecular pathways underlying iron-exacerbated atherosclerosis. Overall, this review highlights a complex framework where NTBI acts at multiple levels in atherosclerosis by altering the serum and vascular microenvironment in a proatherogenic and proinflammatory manner, affecting the functionality and survival of vascular cells, promoting foam cell formation and inducing angiogenesis, calcification, and plaque destabilization. Future Directions: The use of additional iron markers (e.g., NTBI) may help adequately predict predisposition to cardiovascular disease. Clinical studies are needed in the aging population to address the atherogenic role of iron fluctuations within physiological limits and the therapeutic value of iron restriction approaches. Antioxid. Redox Signal. 35, 387-414.

Matrine Impairs Platelet Function and Thrombosis and Inhibits ROS Production

Matrine is a naturally occurring alkaloid and possesses a wide range of pharmacological properties, such as anti-cancer, anti-oxidant, anti-inflammatory effects. However, whether it affects platelet function and thrombosis remains unclear. This study aims to evaluate the effect of matrine on platelet function and thrombus formation. Human platelets were treated with matrine (0–1 mg/ml) for 1 h at 37°C followed by measuring platelet aggregation, granule secretion, receptor expression by flow cytometry, spreading and clot retraction. In addition, matrine (10 mg/kg) was injected intraperitoneally into mice to measure tail bleeding time, arterial and venous thrombus formation. Matrine dose-dependently inhibited platelet aggregation and ATP release in response to either collagen-related peptide (Collagen-related peptide, 0.1 μg/ml) or thrombin (0.04 U/mL) stimulation without altering the expression of P-selectin, glycoprotein Ibα, GPVI, or αIIbβ3. In addition, matrine-treated platelets presented significantly decreased spreading on fibrinogen or collagen and clot retraction along with reduced phosphorylation of c-Src. Moreover, matrine administration significantly impaired the in vivo hemostatic function of platelets, arterial and venous thrombus formation. Furthermore, in platelets stimulated with CRP or thrombin, matrine significantly reduced Reactive oxygen species generation, inhibited the phosphorylation level of ERK1/2 (Thr202/Tyr204), p38 (Thr180/Tyr182) and AKT (Thr308/Ser473) as well as increased VASP phosphorylation (Ser239) and intracellular cGMP level. In conclusion, matrine inhibits platelet function, arterial and venous thrombosis, possibly involving inhibition of ROS generation, suggesting that matrine might be used as an antiplatelet agent for treating thrombotic or cardiovascular diseases.

FXYD1 Is Protective Against Vascular Dysfunction

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Oxidative Stress, Neuroinflammation, and NADPH Oxidase: Implications in the Pathogenesis and Treatment of Alzheimer's Disease

NADPH oxidase as an important source of intracellular reactive oxygen species (ROS) has gained enormous importance over the years, and the detailed structures of all the isoenzymes of the NADPH oxidase family and their regulation have been well explored. The enzyme has been implicated in a variety of diseases including neurodegenerative diseases. The present brief review examines the body of evidence that links NADPH oxidase with the genesis and progression of Alzheimer's disease (AD). In short, evidence suggests that microglial activation and inflammatory response in the AD brain is associated with increased production of ROS by microglial NADPH oxidase. Along with other inflammatory mediators, ROS take part in neuronal degeneration and enhance the microglial activation process. The review also evaluates the current state of NADPH oxidase inhibitors as potential disease-modifying agents for AD.

Association between health risk factors and dietary flavonoid intake in cohort studies

The aim of this study was to identify the health risk factors associated with flavonoid intake in cohort studies investigating the association between dietary polyphenols and the risk of cardiovascular disease (CVD). A systematic search of the PubMed and EMBASE databases was performed. Prospective studies with the background characteristics given for categories of flavonoid intake were eligible to inclusion. A bivariate meta-analysis summarising the intercepts and slopes of the linear regression and a dose-response meta-analysis of differences in means were used to analyse the relationships. The intake of total flavonoids was inversely associated with BMI, alcohol consumption, saturated fat intake, and current smoking, and positively associated with vitamin E, folate, fibre, beta-carotene intake, multivitamin supplement use, and high physical activity. The results of this study underline the importance of considering the association between dietary flavonoid consumption and CVD risk in the context of a healthy lifestyle.

Effects of Cardiovascular, Resistance and Combined Exercise Training on Cardiovascular, Performance and Blood Redox Parameters in Coronary Artery Disease Patients: An 8-Month Training-Detraining Randomized Intervention

It is well-documented that chronic/regular exercise improves the cardiovascular function, decreases oxidative stress and enhances the antioxidant capacity in coronary artery disease (CAD) patients. However, there is insufficient evidence regarding the chronic effects of different types of training and detraining on cardiovascular function and the levels of oxidative stress and antioxidant status in these patients. Therefore, the present study aimed at investigating the effects of cardiovascular, resistance and combined exercise training followed by a three-month detraining period, on cardiovascular function, physical performance and blood redox status parameters in CAD patients. Sixty coronary artery disease patients were randomly assigned to either a cardiovascular training (CVT, N = 15), resistance training (RT, N = 11), combined cardiovascular and resistance training (CT, N = 16) or a control (C, N = 15) group. The training groups participated in an 8-month supervised training program (training three days/week) followed by a 3-month detraining period, while the control group participated only in measurements. Body composition, blood pressure, performance-related variables (aerobic capacity (VO_2max), muscle strength, flexibility) and blood redox status-related parameters (thiobarbituric acid reactive substances (TBARS), total antioxidant capacity (TAC), reduced glutathione (GSH), oxidized glutathione (GSSG), catalase activity (CAT), protein carbonyls (PC)) were assessed at the beginning of the study, after 4 and 8 months of training as well as following 1, 2 and 3 months of detraining (DT). CVT induced the most remarkable and pronounced alterations in blood pressure (~9% reduction in systolic blood pressure and ~5% in diastolic blood pressure) and redox status since it had a positive effect on all redox-related variables (ranging from 16 to 137%). RT and CT training affected positively some of the assessed (TAC, CAT and PC) redox-related variables. Performance-related variables retained the positive response of the training, whereas most of the redox status parameters, for all training groups, restored near to the pre-exercise values at the end of the DT period. These results indicate that exercise training has a significant effect on redox status of CAD. Three months of detraining is enough to abolish the exercise-induced beneficial effects on redox status, indicating that for a better antioxidant status, exercise must be a lifetime commitment.

Protective Effects of Shenfuyixin Granule on H2O2-Induced Apoptosis in Neonatal Rat Cardiomyocytes

Shenfuyixin granule (SFYXG, i.e., Xinshuaikang granule) is a prescription, commonly used in the clinical experience, which plays a significant role in the treatment of heart failure. The purpose of this present research was to investigate the protective effect of SFYXG, and the mechanism about anti-H₂O₂-induced oxidative stress and apoptosis in the neonatal rat cardiomyocytes. Myocardial cells, as is well known, were divided into 4 groups: normal, model, SFYXG, and coenzyme Q10 group, respectively. Cells viability was determined by MTT assay. Flow cytometry and AO/EB staining were implemented to test the apoptosis rate and intracellular reactive oxygen species (ROS) level. Mitochondrion membrane potential (MMP) was evaluated by JC-1 fluorescence probe method. The myocardial ultrastructure of mitochondrion was measured by electron microscope. The related mRNA expression levels of Bax, Bcl-2, Caspase-3, caspase-8, and caspase-9 were detected by real-time polymerase chain reaction (PCR). Also, the expression levels of Bax and Bcl-2 protein were detected by Western blot, and the expression levels of caspase-3, caspase-8, and caspase-9 protein were tested by caspase-Glo®3 Assay, caspase-Glo®8 Assay, and caspase-Glo®9 Assay, respectively. GAPDH was used as the internal reference gene/protein. The results revealed that SFYXG (0.5 mg/ml) raised the viability of myocardial cell, weakened the apoptosis rate and ROS level, corrected the mitochondrion membrane potential stability, and improved cell morphology and ultrastructure of myocardial mitochondrion. Furthermore, SFYXG upregulated the antiapoptosis gene of Bcl-2, but downregulated the proapoptosis genes of Bax, caspase-3, and caspase-9. In conclusion, SFYXG could appear to attenuate myocardial injury by its antioxidative and antiapoptosis effect.

Repurposing drugs to fight aging: The difficult path from bench to bedside

The steady rise in life expectancy occurred across all developed countries during the last century. This demographic trend is, however, not accompanied by the same healthspan extension. This is since aging is the main risk factor for all age-associated pathological conditions. Therefore, slowing the rate of aging is suggested to be more efficient in preventing or delaying age-related diseases than treat them one by one, which is the common approach in a current pharmacological disease-oriented paradigm. To date, a variety of medications designed to treat particular pathological conditions have been shown to exhibit pro-longevity effects in different experimental models. Among them, there are many commonly used prescription and over-the-counter pharmaceuticals such as metformin, rapamycin, aspirin, statins, melatonin, vitamin antioxidants, etc. All of them are being increasingly investigated in preclinical and clinical trials with the aim of determine whether they have potential for extension of human healthspan. The results from these trials are frequently inconclusive and fall short of initial expectations, suggesting that innovative research ideas and additional translational steps are required to overcome obstacles for implementation of such approaches in clinical practice. In this review, recent advances and challenges in the field of repurposing widely used conventional pharmaceuticals to target the aging process are summarized and discussed.

Reactive Oxygen Species: Modulators of Phenotypic Switch of Vascular Smooth Muscle Cells

Reactive oxygen species (ROS) are natural byproducts of oxygen metabolism in the cell. At physiological levels, they play a vital role in cell signaling. However, high ROS levels cause oxidative stress, which is implicated in cardiovascular diseases (CVD) such as atherosclerosis, hypertension, and restenosis after angioplasty. Despite the great amount of research conducted to identify the role of ROS in CVD, the image is still far from being complete. A common event in CVD pathophysiology is the switch of vascular smooth muscle cells (VSMCs) from a contractile to a synthetic phenotype. Interestingly, oxidative stress is a major contributor to this phenotypic switch. In this review, we focus on the effect of ROS on the hallmarks of VSMC phenotypic switch, particularly proliferation and migration. In addition, we speculate on the underlying molecular mechanisms of these cellular events. Along these lines, the impact of ROS on the expression of contractile markers of VSMCs is discussed in depth. We conclude by commenting on the efficiency of antioxidants as CVD therapies.

The Evolving Applications of Creatine Supplementation: Could Creatine Improve Vascular Health?

Creatine is a naturally occurring compound, functioning in conjunction with creatine kinase to play a quintessential role in both cellular energy provision and intracellular energy shuttling. An extensive body of literature solidifies the plethora of ergogenic benefits gained following dietary creatine supplementation; however, recent findings have further indicated a potential therapeutic role for creatine in several pathologies such as myopathies, neurodegenerative disorders, metabolic disturbances, chronic kidney disease and inflammatory diseases. Furthermore, creatine has been found to exhibit non-energy-related properties, such as serving as a potential antioxidant and anti-inflammatory. Despite the therapeutic success of creatine supplementation in varying clinical populations, there is scarce information regarding the potential application of creatine for combatting the current leading cause of mortality, cardiovascular disease (CVD). Taking into consideration the broad ergogenic and non-energy-related actions of creatine, we hypothesize that creatine supplementation may be a potential therapeutic strategy for improving vascular health in at-risk populations such as older adults or those with CVD. With an extensive literature search, we have found only four clinical studies that have investigated the direct effect of creatine on vascular health and function. In this review, we aim to give a short background on the pleiotropic applications of creatine, and to then summarize the current literature surrounding creatine and vascular health. Furthermore, we discuss the varying mechanisms by which creatine could benefit vascular health and function, such as the impact of creatine supplementation upon inflammation and oxidative stress.

Mechanistic Insights into the Oxidized Low-Density Lipoprotein-Induced Atherosclerosis

Dyslipidaemia has a prominent role in the onset of notorious atherosclerosis, a disease of medium to large arteries. Atherosclerosis is the prime root of cardiovascular events contributing to the most considerable number of morbidity and mortality worldwide. Factors like cellular senescence, genetics, clonal haematopoiesis, sedentary lifestyle-induced obesity, or diabetes mellitus upsurge the tendency of atherosclerosis and are foremost pioneers to definitive transience. Accumulation of oxidized low-density lipoproteins (Ox-LDLs) in the tunica intima triggers the onset of this disease. In the later period of progression, the build-up plaques rupture ensuing thrombosis (completely blocking the blood flow), causing myocardial infarction, stroke, and heart attack, all of which are common atherosclerotic cardiovascular events today. The underlying mechanism is very well elucidated in literature but the therapeutic measures remains to be unleashed. Researchers tussle to demonstrate a clear understanding of treating mechanisms. A century of research suggests that lowering LDL, statin-mediated treatment, HDL, and lipid-profile management should be of prime interest to retard atherosclerosis-induced deaths. We shall brief the Ox-LDL-induced atherogenic mechanism and the treating measures in line to impede the development and progression of atherosclerosis.

Ageing and atherosclerosis: vascular intrinsic and extrinsic factors and potential role of IL-6

The number of old people is rising worldwide, and advancing age is a major risk factor for atherosclerotic cardiovascular disease. However, the mechanisms underlying this phenomenon remain unclear. In this Review, we discuss vascular intrinsic and extrinsic mechanisms of how ageing influences the pathology of atherosclerosis. First, we focus on factors that are extrinsic to the vasculature. We discuss how ageing affects the development of myeloid cells leading to the expansion of certain myeloid cell clones and induces changes in myeloid cell functions that promote atherosclerosis via inflammation, including a potential role for IL-6. Next, we describe vascular intrinsic factors by which ageing promotes atherogenesis - in particular, the effects on mitochondrial function. Studies in mice and humans have shown that ageing leads to a decline in vascular mitochondrial function and impaired mitophagy. In mice, ageing is associated with an elevation in the levels of the inflammatory cytokine IL-6 in the aorta, which participates in a positive feedback loop with the impaired vascular mitochondrial function to accelerate atherogenesis. We speculate that vascular and myeloid cell ageing synergize, via IL-6 signalling, to accelerate atherosclerosis. Finally, we propose future avenues of clinical investigation and potential therapeutic approaches to reduce the burden of atherosclerosis in old people.

Repositioning Natural Antioxidants for Therapeutic Applications in Tissue Engineering

Although a large panel of natural antioxidants demonstrate a protective effect in preventing cellular oxidative stress, their low bioavailability limits therapeutic activity at the targeted injury site. The importance to deliver drug or cells into oxidative microenvironments can be realized with the development of biocompatible redox-modulating materials. The incorporation of antioxidant compounds within implanted biomaterials should be able to retain the antioxidant activity, while also allowing graft survival and tissue recovery. This review summarizes the recent literature reporting the combined role of natural antioxidants with biomaterials. Our review highlights how such functionalization is a promising strategy in tissue engineering to improve the engraftment and promote tissue healing or regeneration.

Protective effect of the medicinal herb infusion "horchata" against oxidative damage in cigarette smokers: An ex vivo study

Cigarette smoking has been associated with an increase in oxidative stress (OS) and is considered a predisposing factor to chronic noncommunicable diseases, whilst dietary antioxidants has been proposed as an alternative to cope with this oxidative stress. In this study, 20 smokers and 20 non-smokers were studied with the aim of determining their antioxidant status, as well as the ability of an infusion of 23 medicinal plants, to counteract the damage caused by OS. The plasma, red blood cells (RBCs) and polymorphonuclear cells (PBMCs) of both groups were incubated or not with the horchata infusion extract and then the OS markers, genotoxicity, nanostructure of RBCs membrane and genes related to oxidative responses and cellular functionality were evaluated. Up to 33 different compounds, mainly quercetin glycosides, were identified in the extract. A significant deterioration in the antioxidant status in smokers compared to non-smokers was found. The horchata infusion extract improved the nanostructure of RBCs and DNA damage, as well as the activity of the endogenous antioxidant enzymes and markers of oxidative damage to lipid, and proteins in plasma, RBCs and PBMCs in both groups, whilst no significant changes were found in the expression of different genes related to OS response.