The Future Challenge of Reactive Oxygen Species (ROS) in Hypertension: From Bench to Bed Side

The antihypertensive effect of Alizarin is achieved by activating VEGFR2/eNOS pathway, attenuating oxidative stress-induced mitochondrial damage and premature senescence

The primary and initial manifestations of hypertension encompass arterial hypoelasticity and histiocyte senescence. Oxidative stress plays a pivotal role in the progression of senescence. Elevated intracellular oxidative stress levels will directly induce cell damage, disrupt normal physiological signal transduction, which can cause mitochondrial dysfunction to accelerate the process of senescence. Alizarin, an anthraquinone active ingredient isolated from Rubia cordifolia L., has a variety of pharmacological effects, including antioxidant, anti-inflammatory and anti-platelet. Nevertheless, its potential in lowering blood pressure (BP) and mitigating hypertension-induced vascular senescence remains uncertain. In this study, we used spontaneously hypertensive rats (SHR) and human umbilical vein endothelial cells (HUVECs) to establish a model of vascular senescence in hypertension. Our aim was to elucidate the mechanisms underpinning the vascular protective effects of Alizarin. By assessing systolic blood pressure (SBP) and diastolic blood pressure (DBP), H&E staining, SA-β-Gal staining, vascular function, oxidative stress levels, calcium ion concentration and mitochondrial membrane potential, we found that Alizarin not only restored SBP and increased endothelium-dependent relaxation (EDR) in SHR, but also inhibited oxidative stress-induced mitochondrial damage and significantly delayed the vascular senescence effect in hypertension, and the mechanism may be related to the activation of VEGFR2/eNOS signaling pathway.

Protective effects of the R-(+)-thioctic acid treatment: possible anti-inflammatory activity on heart of hypertensive rats

BACKGROUND

In cardiovascular disease, high blood pressure is associated with oxidative stress, promoting endothelial dysfunction, vascular remodeling, and inflammation. Clinical trials are discordant that the most effective treatment in the management of hypertension seems to be the administration of anti-hypertensive drugs with antioxidant properties. The study aims to evaluate the effects of the eutomer of thioctic acid on oxidative stress and inflammation in the heart of spontaneously hypertensive rats compared to normotensive Wistar Kyoto rats.

METHODS

To study the oxidative status, the malondialdehyde and 4-hydroxynonenal concentration, protein oxidation were measured in the heart. Morphological analysis were performed. Immunohistochemistry and Western blot were done for alpha-smooth muscle actin and transforming growth factor beta to assess fibrosis; cytokines and nuclear factor kappaB to assess inflammatory processes.

RESULTS

Spontaneously hypertensive rats were characterized by hypertension with increased malondialdehyde levels in the heart. OxyBlot in the heart of spontaneously hypertensive rats showed an increase in proteins' oxidative status. Cardiomyocyte hypertrophy and fibrosis in the ventricles were associated with an increased expression of alpha-smooth muscle actin and pro-inflammatory cytokines, reduced by the eutomer of thioctic acid supplementation.

CONCLUSIONS

Based on this evidence, eutomer of thioctic acid could represent an appropriate antioxidant molecule to reduce oxidative stress and prevent inflammatory processes on the cardiomyocytes and cardiac vascular endothelium.

Cardiotoxicity and ROS Protection Assessment of three Structure-Related N-Acylhydrazones with Potential for the Treatment of Neurodegenerative Diseases

The senescence process is associated with accumulated oxidative damage and increased metal concentration in the heart and brain. Besides, abnormal metal-protein interactions have also been linked with the development of several conditions, including Alzheimer's and Parkinson's diseases. Over the years we have described a series of structure-related compounds with different activities towards models of such diseases. In this work, we evaluated the potential of three N-acylhydrazones (INHHQ: 8-hydroxyquinoline-2-carboxaldehyde isonicotinoyl hydrazone, HPCIH: pyridine-2-carboxaldehyde isonicotinoyl hydrazone and X1INH: 1-methyl-1H-imidazole-2-carboxaldehyde isonicotinoyl hydrazone) to prevent oxidative stress in cellular models, with the dual intent of being active on this pathway and also to confirm their lack of cardiotoxicity as an important step in the drug development process, especially considering that the target population often presents cardiovascular comorbidity. The 8-hydroxyquinoline-contaning compound, INHHQ, exhibits a significant cardioprotective effect against hydrogen peroxide and a robust antioxidant activity. However, this compound is the most toxic to the studied cell models and seems to induce oxidative damage on its own. Interestingly, although not possessing a phenol group in its structure, the new-generation 1-methylimidazole derivative X1INH showed a cardioprotective tendency towards H9c2 cells, demonstrating the importance of attaining a compromise between activity and intrinsic cytotoxicity when developing a drug candidate.

Mitochondrial hyperfusion induces metabolic remodeling in lung endothelial cells by modifying the activities of electron transport chain complexes I and III

OBJECTIVE

Pulmonary hypertension (PH) is a progressive disease with vascular remodeling as a critical structural alteration. We have previously shown that metabolic reprogramming is an early initiating mechanism in animal models of PH. This metabolic dysregulation has been linked to remodeling the mitochondrial network to favor fission. However, whether the mitochondrial fission/fusion balance underlies the metabolic reprogramming found early in PH development is unknown.

METHODS

Utilizing a rat early model of PH, in conjunction with cultured pulmonary endothelial cells (PECs), we utilized metabolic flux assays, Seahorse Bioassays, measurements of electron transport chain (ETC) complex activity, fluorescent microscopy, and molecular approaches to investigate the link between the disruption of mitochondrial dynamics and the early metabolic changes that occur in PH.

RESULTS

We observed increased fusion mediators, including Mfn1, Mfn2, and Opa1, and unchanged fission mediators, including Drp1 and Fis1, in a two-week monocrotaline-induced PH animal model (early-stage PH). We were able to establish a connection between increases in fusion mediator Mfn1 and metabolic reprogramming. Using an adenoviral expression system to enhance Mfn1 levels in pulmonary endothelial cells and utilizing 13C-glucose labeled substrate, we found increased production of 13C lactate and decreased TCA cycle metabolites, revealing a Warburg phenotype. The use of a 13C5-glutamine substrate showed evidence that hyperfusion also induces oxidative carboxylation. The increase in glycolysis was linked to increased hypoxia-inducible factor 1α (HIF-1α) protein levels secondary to the disruption of cellular bioenergetics and higher levels of mitochondrial reactive oxygen species (mt-ROS). The elevation in mt-ROS correlated with attenuated ETC complexes I and III activities. Utilizing a mitochondrial-targeted antioxidant to suppress mt-ROS, limited HIF-1α protein levels, which reduced cellular glycolysis and reestablished mitochondrial membrane potential.

CONCLUSIONS

Our data connects mitochondrial fusion-mediated mt-ROS to the Warburg phenotype in early-stage PH development.

Alleviation of Angiotensin II-Induced Vascular Endothelial Cell Injury Through Long Non-coding RNA TUG1 Inhibition

BACKGROUND

Hypertension damages endothelial cells, causing vascular remodelling. It is caused by Ang II-induced endothelial cell (EC) destruction. The long noncoding RNA (lncRNAs) are emerging regulators of endothelium homeostasis. Injured endothelium expresses lncRNA taurine-upregulated gene 1 (TUG1), which may mediate endothelial cell damage, proliferation, apoptosis, and autophagy and contribute to cardiovascular disease. However, uncertainty surrounds the function of lncRNA TUG1, on arterial endothelium cell damage.

OBJECTIVE

This research aimed to investigate the role and mechanism of lncRNA TUG1 in vascular endothelial cell injury.

METHOD

A microarray analysis of lncRNA human gene expression was used to identify differentially expressed lncRNAs in human umbilical vein endothelial cell (HUVEC) cultures. The viability, apoptosis, and migration of Ang II-treated HUVECs were then evaluated. In order to investigate the role of lncRNA TUG1 in hypertension, qRT-PCR, western blotting, and RNA-FISH were used to examine the expression of TUG1 in SHR mice.

RESULTS

Ang II-activated HUVECs and SHR rats' abdominal aortas highly express the lncRNA TUG1. LncRNA TUG1 knockdown in HUVECs could increase cell viability, reduce apoptosis, and produce inflammatory factors. In SHR rat abdominal aortas, lncRNA TUG1 knockdown promoted proliferation and inhibited apoptosis. HE spotting showed that lncRNA TUG1 knockdown improved SHR rats' abdominal aorta shape. lncRNA TUG1 knockdown promotes miR-9- 5p, which inhibits CXCR4 following transcription. The lncRNA TUG1/miR-9-5p/CXCR4 axis and vascular cell injury were also examined. MiR-9-5p silencing or CXCR4 overexpression lowered cell survival, apoptosis, and lncRNA TUG1-induced IL-6 and NO expression.

CONCLUSION

lncRNA TUG1 suppression could reduce Ang II-induced endothelial cell damage by regulating and targeting miR-9-5p to limit CXCR4 expression and open new vascular disease research pathways.

Targeting estrogen receptor signaling for treating heart failure

Heart failure (HF) is a significant public health problem worldwide. It has long been noted that premenopausal women, compared to postmenopausal women and men, have lower rates for developing this disease, as well as subsequent morbidity and mortality. This difference has been attributed to estrogen playing a cardioprotective role in these women, though exactly how it does so remains unclear. In this review, we examine the presence of estrogen receptors within the cardiovascular system, as well as the role they play behind the cardioprotective effect attributed to estrogen. Furthermore, we highlight the underlying mechanisms behind their alleviation of HF, as well as possible treatment approaches, such as hormone replacement therapy and exercise regimens, to manipulate these mechanisms in treating and preventing HF.

Role of copper and its complexes in cardiovascular diseases

Copper is a trace element essential for the maintenance of normal physiological functions in cardiovascular system, and its transport and metabolisms are regulated by various copper proteins such as copper-based enzymes, copper chaperones and copper transporters. The disturbance of copper level or abnormal expression of copper proteins are closely associated with the development of cardiovascular diseases such as atherosclerosis, hypertension, ischemic heart disease, myocardial hypertrophy and heart failure. Thus, intervention of copper ion signaling pathways is expected to be an effective measure for treating cardiovascular diseases. Some copper complexes, such as trientine, copper-aspirinate complex and copper (II) diethyldithiocarbamate, have been found to play a role in the prevention and treatment of cardiovascular diseases and possess potential prospects. Exploring the role of copper in maintaining normal cardiovascular status and the potential application of copper complexes in the treatment of cardiovascular diseases may lay a foundation for finding new targets for prevention and treatment of various cardiovascular diseases, and provide new ideas for clinical treatment of cardiovascular diseases.

Potential Benefits of Antioxidant Phytochemicals in Type 2 Diabetes

The clinical relationship between diabetes and inflammation is well established. Evidence clearly indicates that disrupting oxidant-antioxidant equilibrium and elevated lipid peroxidation could be a potential mechanism for chronic kidney disease associated with type 2 diabetes mellitus (T2DM). Under diabetic conditions, hyperglycemia, especially inflammation, and increased reactive oxygen species generation are bidirectionally associated. Inflammation, oxidative stress, and tissue damage are believed to play a role in the development of diabetes. Although the exact mechanism underlying oxidative stress and its impact on diabetes progression remains uncertain, the hyperglycemia-inflammation-oxidative stress interaction clearly plays a significant role in the onset and progression of vascular disease, kidney disease, hepatic injury, and pancreas damage and, therefore, holds promise as a therapeutic target. Evidence strongly indicates that the use of multiple antidiabetic medications fails to achieve the normal range for glycated hemoglobin targets, signifying treatment-resistant diabetes. Antioxidants with polyphenols are considered useful as adjuvant therapy for their potential anti-inflammatory effect and antioxidant activity. We aimed to analyze the current major points reported in preclinical, in vivo, and clinical studies of antioxidants in the prevention or treatment of inflammation in T2DM. Then, we will share our speculative vision for future diabetes clinical trials.

Optogenetics in Alzheimer's Disease: Focus on Astrocytes

Alzheimer's disease (AD) is the most common form of dementia, resulting in disability and mortality. The global incidence of AD is consistently surging. Although numerous therapeutic agents with promising potential have been developed, none have successfully treated AD to date. Consequently, the pursuit of novel methodologies to address neurodegenerative processes in AD remains a paramount endeavor. A particularly promising avenue in this search is optogenetics, enabling the manipulation of neuronal activity. In recent years, research attention has pivoted from neurons to glial cells. This review aims to consider the potential of the optogenetic correction of astrocyte metabolism as a promising strategy for correcting AD-related disorders. The initial segment of the review centers on the role of astrocytes in the genesis of neurodegeneration. Astrocytes have been implicated in several pathological processes associated with AD, encompassing the clearance of β-amyloid, neuroinflammation, excitotoxicity, oxidative stress, and lipid metabolism (along with a critical role in apolipoprotein E function). The effect of astrocyte-neuronal interactions will also be scrutinized. Furthermore, the review delves into a number of studies indicating that changes in cellular calcium (Ca2+) signaling are one of the causes of neurodegeneration. The review's latter section presents insights into the application of various optogenetic tools to manipulate astrocytic function as a means to counteract neurodegenerative changes.

Oxytetracycline-induced oxidative liver damage by disturbed mitochondrial dynamics and impaired enzyme antioxidants in largemouth bass (Micropterus salmoides)

Oxytetracycline (OTC), a commonly used tetracycline antibiotic in aquaculture, has been found to cause significant damage to the liver of largemouth bass (Micropterus salmoides). This study revealed that OTC can lead to severe histopathological damage, structural changes at the cellular level, and increased levels of reactive oxygen species (ROS) in M. salmoides. Meanwhile, OTC impairs the activities of antioxidant enzyme (such as T-SOD, CAT, GST, GR) by suppressing the activation of MAPK/Nrf2 pathway. OTC disrupts mitochondrial dynamics and mitophagy through via PINK1/Parkin pathway. The accumulation of damaged mitochondria, combined with the inhibition of the antioxidant enzyme system, contributes to elevated ROS levels and oxidative liver damage in M. salmoides. Further investigations demonstrated that an enzyme-treated soy protein (ETSP) dietary supplement can help maintain mitochondrial dynamic balance by inhibiting the PINK1/Parkin pathway and activate the MAPK/Nrf2 pathway to counteract oxidative damage. In summary, these findings highlight that exposure to OTC disrupts mitochondrial dynamics and inhibits the antioxidant enzyme system, ultimately exacerbating oxidative liver damage in M. salmoides. We propose the use of a dietary supplement as a preventive measure against OTC-related side effects, providing valuable insights into the mechanisms of antibiotic toxicity in aquatic environments.

Emerging role of exosomes in vascular diseases

Exosomes are biological small spherical lipid bilayer vesicles secreted by most cells in the body. Their contents include nucleic acids, proteins, and lipids. Exosomes can transfer material molecules between cells and consequently have a variety of biological functions, participating in disease development while exhibiting potential value as biomarkers and therapeutics. Growing evidence suggests that exosomes are vital mediators of vascular remodeling. Endothelial cells (ECs), vascular smooth muscle cells (VSMCs), inflammatory cells, and adventitial fibroblasts (AFs) can communicate through exosomes; such communication is associated with inflammatory responses, cell migration and proliferation, and cell metabolism, leading to changes in vascular function and structure. Essential hypertension (EH), atherosclerosis (AS), and pulmonary arterial hypertension (PAH) are the most common vascular diseases and are associated with significant vascular remodeling. This paper reviews the latest research progress on the involvement of exosomes in vascular remodeling through intercellular information exchange and provides new ideas for understanding related diseases.

The mechanism of low-level arsenic exposure-induced hypertension: Inhibition of the activity of the angiotensin-converting enzyme 2

It is now well-established that arsenic exposure induces hypertension in humans. Although arsenic-induced hypertension is reported in many epidemiological studies, the underlying molecular mechanism of arsenic-induced hypertension is not fully characterized. In the human body, blood pressure is primarily regulated by a well-known physiological system known as the renin-angiotensin system (RAS). Hence, we explored the potential molecular mechanisms of arsenic-induced hypertension by investigating the regulatory roles of the RAS. Adult C57BL/6JJcl male mice were divided into four groups according to the concentration of arsenic in drinking water (0, 8, 80, and 800 ppb) provided for 8 weeks. Arsenic significantly raised blood pressure in arsenic-exposed mice compared to the control group, and significantly raised plasma MDA and Ang II and reduced Ang (1-7) levels. RT-PCR results showed that arsenic significantly downregulated ACE2 and MasR in mice aortas. In vitro studies of endothelial HUVEC cells treated with arsenic showed increased level of MDA and Ang II and lower levels of Ang (1-7), compared with the control. Arsenic significantly downregulated ACE2 and MasR expression, as well as those of Sp1 and SIRT1; transcriptional activators of ACE2, in HUVECs. Arsenic also upregulated markers of endothelial dysfunction (MCP-1, ICAM-1) and inflammatory cytokines (IL-6, TNF-α) in HUVECs. Our findings suggest that arsenic-induced hypertension is mediated, at least in part, by oxidative stress-mediated inhibition of ACE2 as well as by suppressing the vasoprotective axes of RAS, in addition to the activation of the classical axis.

The Mycotoxin Patulin Inhibits the Mitochondrial Carnitine/Acylcarnitine Carrier (SLC25A20) by Interaction with Cys136 Implications for Human Health

The effect of mycotoxin patulin (4-hydroxy-4H-furo [3,2c] pyran-2 [6H] -one) on the mitochondrial carnitine/acylcarnitine carrier (CAC, SLC25A20) was investigated. Transport function was measured as [³H]-carnitine_ex/carnitine_in antiport in proteoliposomes reconstituted with the native protein extracted from rat liver mitochondria or with the recombinant CAC over-expressed in E. coli. Patulin (PAT) inhibited both the mitochondrial native and recombinant transporters. The inhibition was not reversed by physiological and sulfhydryl-reducing reagents, such as glutathione (GSH) or dithioerythritol (DTE). The IC₅₀ derived from the dose-response analysis indicated that PAT inhibition was in the range of 50 µM both on the native and on rat and human recombinant protein. The kinetics process revealed a competitive type of inhibition. A substrate protection experiment confirmed that the interaction of PAT with the protein occurred within a protein region, including the substrate-binding area. The mechanism of inhibition was identified using the site-directed mutagenesis of CAC. No inhibition was observed on Cys mutants in which only the C136 residue was mutated. Mass spectrometry studies and in silico molecular modeling analysis corroborated the outcomes derived from the biochemical assays.

Mechanisms of Arsenic Exposure-Induced Hypertension and Atherosclerosis: an Updated Overview

Arsenic is an abundant element in the earth's crust. In the environment and within the human body, this toxic element can be found in both organic and inorganic forms. Chronic exposure to arsenic can predispose humans to cardiovascular diseases including hypertension, stroke, atherosclerosis, and blackfoot disease. Oxidative damage induced by reactive oxygen species is a major player in arsenic-induced toxicity, and it can affect genes expression, inflammatory responses, and/or nitric oxide homeostasis. Exposure to arsenic in drinking water can lead to vascular endothelial dysfunction which is reflected by an imbalance between vascular relaxation and contraction. Arsenic has been shown to inactivate endothelial nitric oxide synthase leading to a reduction of the generation and bioavailability of nitric oxide. Ultimately, these effects increase the risk of vascular diseases such as hypertension and atherosclerosis. The present article reviews how arsenic exposure contributes to hypertension and atherosclerosis development.

Parkia speciosa Hassk. Empty Pod Extract Prevents Cardiomyocyte Hypertrophy by Inhibiting MAPK and Calcineurin-NFATC3 Signaling Pathways

Cardiac hypertrophy is an early hallmark during the clinical course of heart failure. Therapeutic strategies aiming to alleviate cardiac hypertrophy via the mitogen-activated protein kinase (MAPK)/calcineurin-nuclear factor of activated T-cells (NFAT) signaling pathway may help prevent cardiac dysfunction. Previously, empty pod ethanol crude extract of Parkia speciosa Hassk was shown to demonstrate protective effects against cardiomyocyte hypertrophy. Therefore, the current study aimed to investigate the effects of various fractions of the plant ethanol extract on the MAPK/NFAT signaling pathway in angiotensin II (Ang II)-induced cardiomyocyte hypertrophy. Simultaneous treatment with ethyl acetate (EA) fraction produced the most potent antihypertrophic effect evidenced by the reduced release of B-type natriuretic peptide (BNP). Subsequently, treatment with the EA fraction (6.25, 12.5, and 25 μg/mL) prevented an Ang II-induced increase in cell surface area, hypertrophic factors (atrial natriuretic peptide and BNP), reactive oxygen species, protein content, and NADPH oxidase 4 expression in the cells. Furthermore, EA treatment attenuated the activation of the MAPK pathway and calcineurin-related pathway (GATA-binding protein 4 and NFATC3), which was similar to the effects of valsartan (positive control). Our findings indicate that the EA fraction prevents Ang II-induced cardiac hypertrophy by regulating the MAPK/calcineurin-NFAT signaling pathway.

Oxidative Regulation of Vascular Cav1.2 Channels Triggers Vascular Dysfunction in Hypertension-Related Disorders

Blood pressure is determined by cardiac output and peripheral vascular resistance. The L-type voltage-gated Ca²⁺ (Ca_v1.2) channel in small arteries and arterioles plays an essential role in regulating Ca²⁺ influx, vascular resistance, and blood pressure. Hypertension and preeclampsia are characterized by high blood pressure. In addition, diabetes has a high prevalence of hypertension. The etiology of these disorders remains elusive, involving the complex interplay of environmental and genetic factors. Common to these disorders are oxidative stress and vascular dysfunction. Reactive oxygen species (ROS) derived from NADPH oxidases (NOXs) and mitochondria are primary sources of vascular oxidative stress, whereas dysfunction of the Ca_v1.2 channel confers increased vascular resistance in hypertension. This review will discuss the importance of ROS derived from NOXs and mitochondria in regulating vascular Ca_v1.2 and potential roles of ROS-mediated Ca_v1.2 dysfunction in aberrant vascular function in hypertension, diabetes, and preeclampsia.

G-protein coupled receptor 30 attenuates myocardial hypertrophy by reducing oxidative stress and apoptosis in Ang II-treated mice

G protein-coupled receptors (GPCRs) are the largest family of membrane receptors that mediate the effects of cardiac diseases. GPR30, also named G-protein-coupled estrogen receptor, shows beneficial effect on female patients with heart failure. This research aimed to probe the role and mechanism of GPR30 in myocardial hypertrophy. The model of cardiac hypertrophy was induced by infusion of angiotensin (Ang) II in mice, and was induced by Ang II treatment in neonatal rat cardiomyocyte (NRCM). The mouse model of myocardial hypertrophy was induced by angiotensin (Ang) Ⅱ, and the neonatal rat cardiomyocyte (NRCM) was induced by Ang Ⅱ treatment. GPR30 agonist G1 reduced cardiac hypertrophy induced by Ang II in mice, and reduced cardiac atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP) and β-myosin heavy chain (β-MHC) induced by Ang II. Ang Ⅱ treatment of myocardial fibrosis in mice was suppressed after administration of G1. GPR30 deficiency produced the opposite results. Oxidative stress and apoptosis were enhanced in the mice heart induced by Ang II, which were suppressed by G1 administration, but were further exacerbated after GPR30 deficiency. The outcomes demonstrated that GPR30 participated in the regulation of cardiac hypertrophy and fibrosis. Activation of GPR30 ameliorated cardiac hypertrophy and fibrosis by reducing oxidative stress and apoptosis.

Application of Reactive Oxygen Species in Dental Treatment

Reactive oxygen species (ROS) and free radicals, which have been implicated in inflammation, pain, carcinogenesis, and aging, are actually used in dental treatments such as tooth bleaching and composite resin polymerization. Recently, numerous studies have investigated the application of ROS in the medical and dental fields. In previous studies, ROS were generated intentionally through pathways such as photolysis, photocatalytic methods, and photodynamic therapy, which are used in the medical field to target cancer. In the field of dentistry, generated ROS are applied mainly for periodontal treatment and sterilization of the root canal, and its effectiveness as an antibacterial photodynamic therapy has been widely reported.. Given this background, the present article aimed to review the basic effects of ROS in dental medicine, especially endodontic therapy, and to discuss future applications of ROS.

The Prognostic Value of Derivatives-Reactive Oxygen Metabolites (d-ROMs) for Cardiovascular Disease Events and Mortality: A Review

Oxidative stress participates in the development and exacerbation of cardiovascular diseases (CVD). The ability to promptly quantify an imbalance in an individual reductive-oxidative (RedOx) state could improve cardiovascular risk assessment and management. Derivatives-reactive oxygen metabolites (d-ROMs) are an emerging biomarker of oxidative stress quantifiable in minutes through standard biochemical analysers or by a bedside point-of-care test. The current review evaluates available data on the prognostic value of d-ROMs for CVD events and mortality in individuals with known and unknown CVD. Outcome studies involving small and large cohorts were analysed and hazard ratio, risk ratio, odds ratio, and mean differences were used as measures of effect. High d-ROM plasma levels were found to be an independent predictor of CVD events and mortality. Risk begins increasing at d-ROM levels higher than 340 UCARR and rises considerably above 400 UCARR. Conversely, low d-ROM plasma levels are a good negative predictor for CVD events in patients with coronary artery disease and heart failure. Moreover, combining d-ROMs with other relevant biomarkers routinely used in clinical practice might support a more precise cardiovascular risk assessment. We conclude that d-ROMs represent an emerging oxidative-stress-related biomarker with the potential for better risk stratification both in primary and secondary cardiovascular prevention.

Melatonin improves arsenic-induced hypertension through the inactivation of the Sirt1/autophagy pathway in rat

Arsenic (As), a metalloid chemical element, is classified as heavy metal. Previous studies proposed that As induces vascular toxicity by inducing autophagy, apoptosis, and oxidative stress. It has been shown that melatonin (Mel) can decrease oxidative stress and apoptosis, and modulate autophagy in different pathological situations. Hence, this study aimed to investigate the Mel effect on As-induced vascular toxicity through apoptosis and autophagy regulation. Forty male rats were treated with As (15 mg/kg; oral gavage) and Mel (10 and 20 mg/kg, intraperitoneally; i.p.) for 28 days. The systolic blood pressure (SBP) changes, oxidative stress markers, the aorta histopathological injuries, contractile and relaxant responses, the level of apoptosis (Bnip3 and caspase-3) and autophagy (Sirt1, Beclin-1 and LC3 II/I ratio) proteins were determined in rats aorta. The As exposure significantly increased SBP and enhanced MDA level while reduced GSH content. The exposure to As caused substantial histological damage in aorta tissue and changed vasoconstriction and vasorelaxation responses to KCl, PE, and Ach in isolated rat aorta. The levels of HO-1 and Nrf-2, apoptosis markers, Sirt1, and autophagy proteins also enhanced in As group. Interestingly, Mel could reduce changes in oxidative stress, blood pressure, apoptosis, and autophagy induced by As. On the other hand, Mel led to more increased the levels of Nrf-2 and HO-1 proteins compared with the As group. In conclusion, our findings showed that Mel could have a protective effect against As-induced vascular toxicity by inhibiting apoptosis and the Sirt1/autophagy pathway.

Inhibition of eNOS Partially Blunts the Beneficial Effects of Nebivolol on Angiotensin II-Induced Signaling in H9c2 Cardiomyoblasts

We have recently illustrated that nebivolol can inhibit angiotensin II (Ang II)-mediated signaling in cardiomyoblasts; however, to date, the detailed mechanism for the beneficial effects of nebivolol has not been studied. Here, we investigated whether the inhibition of NO bioavailability by blocking eNOS (endothelial nitric oxide synthase) using L-NG-nitroarginine methyl ester (L-NAME) would attenuate nebivolol-mediated favorable effects on Ang II-evoked signaling in H9c2 cardiomyoblasts. Our data reveal that the nebivolol-mediated antagonistic effects on Ang II-induced oxidative stress were retreated by concurrent pretreatment with L-NAME and nebivolol. Similarly, the expressions of pro-inflammatory markers TNF-α and iNOS stimulated by Ang II were not decreased with the combination of nebivolol plus L-NAME. In contrast, the nebivolol-induced reduction in the Ang II-triggered mTORC1 pathway and the mRNA levels of hypertrophic markers ANP, BNP, and β-MHC were not reversed with the addition of L-NAME to nebivolol. In compliance with these data, the inhibition of eNOS by L-N⁵-(1-Iminoethyl) ornithine (LNIO) and its upstream regulator AMP-activated kinase (AMPK) with compound C in the presence of nebivolol showed effects similar to those of the L-NAME plus nebivolol combination on Ang II-mediated signaling. Pretreatment with either compound C plus nebivolol or LNIO plus nebivolol showed similar effects to those of the L-NAME plus nebivolol combination on Ang II-mediated signaling. In conclusion, our data indicate that the rise in NO bioavailability caused by nebivolol via the stimulation of AMPK/eNOS signaling is key for its anti-inflammatory and antioxidant properties but not for its antihypertrophic response upon Ang II stimulation.

Oxidative Stress in Arterial Hypertension (HTN): The Nuclear Factor Erythroid Factor 2-Related Factor 2 (Nrf2) Pathway, Implications and Future Perspectives

Arterial hypertension (HTN) is one of the most prevalent entities globally, characterized by increased incidence and heterogeneous pathophysiology. Among possible etiologies, oxidative stress (OS) is currently extensively studied, with emerging evidence showing its involvement in endothelial dysfunction and in different cardiovascular diseases (CVD) such as HTN, as well as its potential as a therapeutic target. While there is a clear physiological equilibrium between reactive oxygen species (ROS) and antioxidants essential for many cellular functions, excessive levels of ROS lead to vascular cell impairment with decreased nitric oxide (NO) availability and vasoconstriction, which promotes HTN. On the other hand, transcription factors such as nuclear factor erythroid factor 2-related factor 2 (Nrf2) mediate antioxidant response pathways and maintain cellular reduction-oxidation homeostasis, exerting protective effects. In this review, we describe the relationship between OS and hypertension-induced endothelial dysfunction and the involvement and therapeutic potential of Nrf2 in HTN.

Oxidative stress in obesity and insulin resistance

Since obesity is one of the main factors in the development of insulin resistance (IR) and is also associated with increased oxidative stress (OxS) rate, this study aims to review the published literature to collate and provide a comprehensive summary of the studies related to the status of the OxS in the pathogenesis of obesity and related IR. OxS represents an imbalance between the production of reactive oxygen and nitrogen species (RONS) and the capacity of the antioxidant defense system (AOS) to neutralize RONS. A steady-state of RONS level is maintained through endogenous enzymatic and non-enzymatic AOS components. Three crucial enzymes, which suppress the formation of free radicals, are superoxide dismutases, catalases, and glutathione peroxidases. The second line of AOS includes non-enzymatic components such as vitamins C and E, coenzyme Q, and glutathione which neutralizes free radicals by donating electrons to RONS. Emerging evidence suggests that high RONS levels contribute to the progression of OxS in obesity by activating inflammatory pathways and thus leading to the development of pathological states, including IR. In addition, decreased level of AOS components in obesity increases the susceptibility to oxidative tissue damage and further progression of its comorbidities. Increased OxS in accumulated adipose tissue should be an imperative target for developing new therapies in obesity-related IR.

Integrating network pharmacology and non-targeted metabolomics to explore the common mechanism of Coptis Categorized Formula improving T2DM zebrafish

ETHNOPHARMACOLOGICAL RELEVANCE

Coptis Categorized Formula (CCF) is one of the core prescriptions in Treatise on Febrile Diseases. Its efficacy can be available not only in exogenous diseases but widely in various internal injuries and miscellaneous diseases. CCF (i.e., Huanglian Jiedu Decoction, Huanglian Ejiao Decoction, Dahuang Huanglian Xiexin Decoction, Gegen Qinlian Decoction) is different in composition, but they all play a favorable role in curative effect on type 2 diabetes mellitus (T2DM). Therefore, it is of great significance to reveal the common mechanism of CCF in treating T2DM.

AIM OF THE STUDY

Based on network pharmacology and non-targeted metabolomics research strategy, the common mechanism of the CCF treating T2DM was discussed.

MATERIALS AND METHODS

Firstly, Ultra-high performance liquid chromatography-quadrupole-time of flight/mass spectrometry was used to identify the chemical constituents of the CCF. Then, the targets of these chemical components were used for network pharmacology analysis associated with therapeutic effect. Finally, the diabetic zebrafish model was constructed to further verify the common mechanism of the CCF in treating T2DM.

RESULTS

A total of 160 chemical compositions were identified and 16 of them were common chemical compositions of the four CCF, including berberine, baicalin, coptisine and so forth. Network pharmacology results showed that Dipeptidyl peptidase (DPP)-4, cysteinyl aspartate specific proteinase (CASP)3, nitric oxide synthase (NOS)2, NOS3, and other 37 targets were common targets of CCF, and advanced glycation end products (AGE)-receptor of advanced glycation end products (RAGE) signaling pathway in diabetic complications, mitogen-activated protein kinase (MAPK) signaling pathway and hypoxia inducible factor (HIF)-1 signaling pathway were critical pathways of four CCF in the treatment of T2DM. CCF can lessen the blood glucose of diabetic zebrafish. The contents of 25 differential metabolites in diabetic zebrafish were altered. These metabolites were mainly related to phenylalanine, tyrosine and tryptophan biosynthesis, phenylalanine metabolism, arachidonic acid metabolism, sphingolipid metabolism, and tyrosine metabolism.

CONCLUSION

Our research shows that the common mechanism of CCF in improving T2DM is as follows: berberine, baicalin, coptisine and other chemical components can directionally regulate DPP-4, CASP3, NOS2, NOS3 and other targets, which are mediated by AGE-RAGE signaling pathway in diabetic complications, MAPK signaling pathway and HIF-1 signaling pathway. The content of endogenous metabolites such as L-valine and L-sorbitose changes, and further regulates the metabolism of amino acid metabolism, lipid metabolism, purine metabolism, sphingosine metabolism and arachidonic acid metabolism, so as to play a significant role in regulating glycolipid metabolism, improving insulin resistance, inhibiting cell apoptosis, anti-oxidation and anti-inflammation, and finally ameliorating T2DM.

Polyphenols as Antioxidants for Extending Food Shelf-Life and in the Prevention of Health Diseases: Encapsulation and Interfacial Phenomena

Toxicity caused by the exposure to human-made chemicals and environmental conditions has become a major health concern because they may significantly increase the formation of reactive oxygen species (ROS), negatively affecting the endogenous antioxidant defense. Living systems have evolved complex antioxidant mechanisms to protect cells from oxidative conditions. Although oxidative stress contributes to various pathologies, the intake of molecules such as polyphenols, obtained from natural sources, may limit their effects because of their antioxidant and antimicrobial properties against lipid peroxidation and against a broad range of foodborne pathogens. Ingestion of polyphenol-rich foods, such as fruits and vegetables, help to reduce the harmful effects of ROS, but the use of supramolecular and nanomaterials as delivery systems has emerged as an efficient method to improve their pharmacological and therapeutic effects. Suitable exogenous polyphenolic antioxidants should be readily absorbed and delivered to sites where pathological oxidative damage may take place, for instance, intracellular locations. Many potential antioxidants have a poor bioavailability, but they can be encapsulated to improve their ideal solubility and permeability profile. Development of effective antioxidant strategies requires the creation of new nanoscale drug delivery systems to significantly reduce oxidative stress. In this review we provide an overview of the oxidative stress process, highlight some properties of ROS, and discuss the role of natural polyphenols as bioactives in controlling the overproduction of ROS and bacterial and fungal growth, paying special attention to their encapsulation in suitable delivery systems and to their location in colloidal systems where interfaces play a crucial role.

Cytoprotective Peptides from Blue Mussel Protein Hydrolysates: Identification and Mechanism Investigation in Human Umbilical Vein Endothelial Cells Injury

Cardiovascular disease represents a leading cause of mortality and is often characterized by the emergence of endothelial dysfunction (ED), a physiologic condition that takes place in the early progress of atherosclerosis. In this study, two cytoprotective peptides derived from blue mussel chymotrypsin hydrolysates with the sequence of EPTF and FTVN were purified and identified. Molecular mechanisms underlying the cytoprotective effects against oxidative stress which lead to human umbilical vein endothelial cells (HUVEC) injury were investigated. The results showed that pretreatment of EPTF, FTVN and their combination (1:1) in 0.1 mg/mL significantly reduced HUVEC death due to H₂O₂ exposure. The cytoprotective mechanism of these peptides involves an improvement in the cellular antioxidant defense system, as indicated by the suppression of the intracellular ROS generation through upregulation of the cytoprotective enzyme heme oxygenase-1. In addition, H₂O₂ exposure triggers HUVEC damage through the apoptosis process, as evidenced by increased cytochrome C release, Bax protein expression, and the elevated amount of activated caspase-3, however in HUVEC pretreated with peptides and their combination, the presence of those apoptotic stimuli was significantly decreased. Each peptide showed similar cytoprotective effect but no synergistic effect. Taken together, these peptides may be especially important in protecting against oxidative stress-mediated ED.

Increased plasma disequilibrium between pro- and anti-oxidants during the early phase resuscitation after cardiac arrest is associated with increased levels of oxidative stress end-products

BACKGROUND

Cardiac arrest (CA) results in loss of blood circulation to all tissues leading to oxygen and metabolite dysfunction. Return of blood flow and oxygen during resuscitative efforts is the beginning of reperfusion injury and is marked by the generation of reactive oxygen species (ROS) that can directly damage tissues. The plasma serves as a reservoir and transportation medium for oxygen and metabolites critical for survival as well as ROS that are generated. However, the complicated interplay among various ROS species and antioxidant counterparts, particularly after CA, in the plasma have not been evaluated. In this study, we assessed the equilibrium between pro- and anti-oxidants within the plasma to assess the oxidative status of plasma post-CA.

METHODS

In male Sprague-Dawley rats, 10 min asphyxial-CA was induced followed by cardiopulmonary resuscitation (CPR). Plasma was drawn immediately after achieving return of spontaneous circulation (ROSC) and after 2 h post-ROSC. Plasma was isolated and analyzed for prooxidant capacity (Amplex Red and dihydroethidium oxidation, total nitrate and nitrite concentration, xanthine oxidase activity, and iron concentration) and antioxidant capacity (catalase and superoxide dismutase activities, Total Antioxidant Capacity, and Iron Reducing Antioxidant Power Assay). The consequent oxidative products, such as 4-Hydroxyl-2-noneal, malondialdehyde, protein carbonyl, and nitrotyrosine were evaluated to determine the degree of oxidative damage.

RESULTS

After CA and resuscitation, two trends were observed: (1) plasma prooxidant capacity was lower during ischemia, but rapidly increased post-ROSC as compared to control, and (2) plasma antioxidant capacity was increased during ischemia, but either decreased or did not increase substantially post-ROSC as compared to control. Consequently, oxidation products were increased post-ROSC.

CONCLUSION

Our study evaluated the disbalance of pro- and anti-oxidants after CA in the plasma during the early phase after resuscitation. This disequilibrium favors the prooxidants and is associated with increased levels of downstream oxidative stress-induced end-products, which the body's antioxidant capacity is unable to directly mitigate. Here, we suggest that circulating plasma is a major contributor to oxidative stress post-CA and its management requires substantial early intervention for favorable outcomes.

DRD4 (Dopamine D4 Receptor) Mitigate Abdominal Aortic Aneurysm via Decreasing P38 MAPK (mitogen-activated protein kinase)/NOX4 (NADPH Oxidase 4) Axis-Associated Oxidative Stress

[Figure: see text].

Cytoprotective Mechanisms of DJ-1: Implications in Cardiac Pathophysiology

DJ-1 was originally identified as an oncogene product while mutations of the gene encoding DJ-1/PARK7 were later associated with a recessive form of Parkinson's disease. Its ubiquitous expression and diversity of function suggest that DJ-1 is also involved in mechanisms outside the central nervous system. In the last decade, the contribution of DJ-1 to the protection from ischemia-reperfusion injury has been recognized and its involvement in the pathophysiology of cardiovascular disease is attracting increasing attention. This review describes the current and gaps in our knowledge of DJ-1, focusing on its role in regulating cardiovascular function. In parallel, we present original data showing an association between increased DJ-1 expression and antiapoptotic and anti-inflammatory markers following cardiac and vascular surgical procedures. Future studies should address DJ-1's role as a plausible novel therapeutic target for cardiovascular disease.

Nrf1 Knock-Down in the Hypothalamic Paraventricular Nucleus Alleviates Hypertension Through Intervention of Superoxide Production-Removal Balance and Mitochondrial Function

Oxidative stress in the hypothalamic paraventricular nucleus (PVN) contributes greatly to the development of hypertension. The recombinant nuclear respiratory factor 1 (Nrf1) regulates the transcription of several genes related to mitochondrial respiratory chain function or antioxidant expression, and thus may be involved in the pathogenesis of hypertension. Here we show that in the two-kidney, one-clip (2K1C) hypertensive rats the transcription level of Nrf1 was elevated comparing to the normotensive controls. Knocking down of Nrf1 in the PVN of 2K1C rats can significantly reduce their blood pressure and level of plasma norepinephrine (NE). Analysis revealed significant reduction of superoxide production level in both whole cell and mitochondria, along with up-regulation of superoxide dismutase 1 (Cu/Zn-SOD), NAD(P)H: quinone oxidoreductase 1 (NQO1), thioredoxin-dependent peroxiredoxin 3 (Prdx3), cytochrome c (Cyt-c) and glutathione synthesis rate-limiting enzyme (glutamyl-cysteine ligase catalytic subunit (Gclc) and modifier subunit (Gclm)), and down-regulation of cytochrome c oxidase subunit VI c (Cox6c) transcription after Nrf1 knock-down. In addition, the reduced ATP production and elevated mitochondrial membrane potential in the PVN of 2K1C rats were reinstated with Nrf1 knock-down, together with restored expression of peroxisome proliferator-activated receptor-γ coactivator 1α (PGC-1α), mitochondrial transcription factor A (Tfam), coiled-coil myosin-like BCL2-interacting protein (Beclin1), and Mitofusin 1 (Mfn1), which are related to the mitochondrial biogenesis, fusion, and autophagy. Together, the results indicate that the PVN Nrf1 is associated with the development of 2K1C-induced hypertension, and Nrf1 knock-down in the PVN can alleviate hypertension through intervention of mitochondrial function and restorement of the production-removal balance of superoxide.

Coordinated Contribution of NADPH Oxidase- and Mitochondria-Derived Reactive Oxygen Species in Metabolic Syndrome and Its Implication in Renal Dysfunction

Metabolic syndrome (MetS), a complex of interrelated risk factors for cardiovascular disease and diabetes, is comprised of central obesity (increased waist circumference), hyperglycemia, dyslipidemia (high triglyceride blood levels, low high-density lipoprotein blood levels), and increased blood pressure. Oxidative stress, caused by the imbalance between pro-oxidant and endogenous antioxidant systems, is the primary pathological basis of MetS. The major sources of reactive oxygen species (ROS) associated with MetS are nicotinamide-adenine dinucleotide phosphate (NADPH) oxidases and mitochondria. In this review, we summarize the current knowledge regarding the generation of ROS from NADPH oxidases and mitochondria, discuss the NADPH oxidase- and mitochondria-derived ROS signaling and pathophysiological effects, and the interplay between these two major sources of ROS, which leads to chronic inflammation, adipocyte proliferation, insulin resistance, and other metabolic abnormalities. The mechanisms linking MetS and chronic kidney disease are not well known. The role of NADPH oxidases and mitochondria in renal injury in the setting of MetS, particularly the influence of the pyruvate dehydrogenase complex in oxidative stress, inflammation, and subsequent renal injury, is highlighted. Understanding the molecular mechanism(s) underlying MetS may lead to novel therapeutic approaches by targeting the pyruvate dehydrogenase complex in MetS and prevent its sequelae of chronic cardiovascular and renal diseases.

Renal Dopamine Receptors and Oxidative Stress: Role in Hypertension

Significance: The kidney plays an important role in the long-term control of blood pressure. Oxidative stress is one of the fundamental mechanisms responsible for the development of hypertension. Dopamine, via five subtypes of receptors, plays an important role in the control of blood pressure by various mechanisms, including the inhibition of oxidative stress. Recent Advances: Dopamine receptors exert their regulatory function to decrease the oxidative stress in the kidney and ultimately maintain normal sodium balance and blood pressure homeostasis. An aberration of this regulation may be involved in the pathogenesis of hypertension. Critical Issues: Our present article reviews the important role of oxidative stress and intrarenal dopaminergic system in the regulation of blood pressure, summarizes the current knowledge on renal dopamine receptor-mediated antioxidation, including decreasing reactive oxygen species production, inhibiting pro-oxidant enzyme nicotinamide-adenine dinucleotide phosphate (NADPH) oxidase, and stimulating antioxidative enzymes, and also discusses its underlying mechanisms, including the increased activity of G protein-coupled receptor kinase 4 (GRK4) and abnormal trafficking of renal dopamine receptors in hypertensive status. Future Directions: Identifying the mechanisms of renal dopamine receptors in the regulation of oxidative stress and their contribution to the pathogenesis of hypertension remains an important research focus. Increased understanding of the role of reciprocal regulation between renal dopamine receptors and oxidative stress in the regulation of blood pressure may give us novel insights into the pathogenesis of hypertension and provide a new treatment strategy for hypertension.

Effects of virgin coconut oil consumption on metabolic syndrome components and asymmetric dimethylarginine: A randomized controlled clinical trial

BACKGROUND AND AIMS

There is some promising evidence regarding the beneficial effect of coconut oil on cardiometabolic risk factors. This study aimed to assess the effects of virgin coconut oil (VCO) consumption on metabolic syndrome (MetS) components, as well as, asymmetric dimethylarginine (ADMA) in adults with MetS.

METHODS AND RESULTS

In this randomized controlled trial, 48 subjects, aged 20-50 years, with MetS were allocated into two groups; the intervention group was given 30 ml of VCO per day to substitute the same amounts of fat in their usual diet for four weeks. The control group was advised to follow their usual diet. VCO consumption significantly reduced serum levels of triglyceride (TG) (P = 0.001), very low-density lipoprotein (VLDL) (P = 0.001), and fasting blood sugar (FBS) (P = 0.015) compared to the control group. The levels of high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and total cholesterol (TC) were significantly increased in the VCO group when compared to the control group (P = 0.001). Circulatory ADMA also increased in the VCO group compared to the control group (P = 0.003). No significant differences were observed in the LDL-C/HDL-C ratio, anthropometric parameters, and blood pressure measurements between the two groups at the end of the study (P > 0.05).

CONCLUSION

VCO consumption increased the values of HDL-C while reduced TG and FBS levels. Blood pressure and waist circumference did not change. However, levels of TC, LDL-C, and ADMA elevated by VCO consumption. Caution is warranted until the results of further studies become available to explain the long-term effects of VCO consumption.

REGISTRATION NUMBER

IRCT20131125015536N11.

Exosomal microRNAs in the development of essential hypertension and its potential as biomarkers

MicroRNAs (miRNAs) are small regulatory molecules that are involved in posttranscriptional modifications. These noncoding RNAs are usually ferried by extracellular carriers such as exosomes or other protein and lipid carriers inside a range of body fluids including plasma and urine. Due to their ability to withstand harsh external conditions, exosomal miRNAs possess enormous potential as noninvasive disease biomarkers for, notably hypertension, whereby exosomal miRNAs have been implicated in its pathophysiological processes. More importantly, alterations in the microenvironment as a result of disease progression can induce active and selective loading of miRNAs into exosomes. In this paper, we first review the mechanisms of miRNA loading into exosomes, followed by the roles of exosomal miRNAs in the development of hypertension, and the potentials of exosomal miRNAs as biomarkers in comparison with other free circulating miRNAs. Finally, challenges and future research surrounding exosomal miRNAs will also be discussed. This review will aid in the understanding of noninvasive biomarkers for the early diagnosis of hypertension and for probing therapeutic efficacy.

Sestrin 2, a potential star of antioxidant stress in cardiovascular diseases

Physiological reactive oxygen species (ROS) play an important role in cellular signal transduction. However, excessive ROS is an important pathological mechanism in most cardiovascular diseases (CVDs), such as myocardial aging, cardiomyopathy, ischemia/reperfusion injury (e.g., myocardial infarction) and heart failure. Programmed cell death, hypertrophy and fibrosis may be due to oxidative stress. Sestrin 2 (Sesn2), a stress-inducible protein associated with various stress conditions, is a potential antioxidant. Sesn2 can suppress the process of heart damage caused by oxidative stress, promote cell survival and play a key role in a variety of CVDs. This review discusses the effect of Sesn2 on the redox signal, mainly via participation in the signaling pathway of nuclear factor erythroid 2-related factor 2, activation of adenosine monophosphate-activated protein kinase and inhibition of mammalian target of rapamycin complex 1. It also discusses the effect of Sesn2's antioxidant activity on different CVDs. We speculate that Sesn2 plays an important role in CVDs by stimulating the process of antioxidation and promoting the adaptation of cells to stress conditions and/or the environment, opening a new avenue for related therapeutic strategies.

Endothelial Dysfunction and Its Clinical Implications

Endothelial dysfunction (ED) plays a substantial role in the pathogenesis of atherosclerosis and some other vascular diseases. ED has been demonstrated in patients with hypercholesterolemia, diabetes, smoking, hypertension, and in patients with atherosclerotic disease. Besides classical risk factors, ED is affected by chronic inflammatory diseases and acute infections, particularly viral diseases. Causes of ED include oxidative stress, inflammation, and shear stress, which decrease the bioavailability of nitric oxide. Markers of ED have been sought, particularly circulating markers. Using these tests, it is possible to evaluate the response to harmful effects of risk factors and the effects of treatment on vessel wall function. Endothelial dysfunction is significantly and directly correlated with the occurrence of cardiac events and the risk of cardiac events increase as ED worsens. Because endothelial function plays a central role in atherogenesis it became a therapeutic target. Endothelial dysfunction is reversible and its improvement may be achieved by elimination of risk factors, inhibitors of endothelium-derived contracting factors (angiotensin-converting enzyme), smoking cessation, lipid-lowering drugs, diet, and physical exercise. By reversing ED, it is possible to restore vascular function.

An Overview of Vascular Dysfunction and Determinants: The Case of Children of African Ancestry

The balance between dilatory and constrictive factors is important as it keeps blood vessels in a homeostatic state. However, altered physiological processes as a result of obesity, hypertension, oxidative stress, and other cardiovascular risk factors may lead to vascular damage, causing an imbalance of vasoactive factors. Over time, the sustained imbalance of these vasoactive factors may lead to vascular dysfunction, which can be assessed by non-invasive methods, such as flow-mediated dilation, pulse wave velocity, flow-mediated slowing, retinal vessel analysis, peripheral vascular reactivity, and carotid intima-media thickness assessment. Although there is increasing prevalence of cardiovascular risk factors (obesity and hypertension) in children in sub-Saharan Africa, little is known about how this may affect vascular function. This review focuses on vasoactive factors implicated in vascular (dys)function, highlighting the determinants and consequences of vascular dysfunction. It further describes the non-invasive methods used for vascular (dys)function assessments and, last, describes the impact of cardiovascular risk factors on vascular dysfunction in children of African ancestry.

Qingda granule attenuates angiotensin II-induced cardiac hypertrophy and apoptosis and modulates the PI3K/AKT pathway

Qingda granule (QDG), simplified from Qingxuan Jiangya Decoction, is a well-known traditional Chinese medicine formula that has been used for decades to treat hypertension. However, the cardioprotective effects of QDG on Ang II-induced hypertension remain unknown. This study aimed to investigate the effects of QDG on hypertension-induced cardiac hypertrophy and apoptosis, as well as explore its underlying mechanisms. Mice were infused with Ang II (500 ng/kg/min) or saline solution as control, then administered oral QDG (1.145 g/kg/day) or saline for two weeks. QDG treatment attenuated the elevation in blood pressure caused by Ang II, as well as the decreased left ventricle ejection fractions and fractional shortening. Moreover, QDG treatment significantly alleviated the Ang II-induced elevation of the ratio of heart weight to tibia length, as well as cardiac injury, hypertrophy, and apoptosis. In cultured H9C2 cells stimulated with Ang II, QDG partially reversed the increase in cell surface area and number of apoptotic cells, up-regulation of hypertrophy markers ANP and BNP, and activation of caspases-9 and -3. QDG also partially reversed Ang II-induced accumulation of reactive oxygen species (ROS), depolarization of the mitochondrial membrane, release of cytochrome C, up-regulation of Bax, and decrease in levels of p-PI3K, p-AKT, and Bcl-2. These results suggest that QDG can significantly attenuate Ang II-induced hypertension, cardiac hypertrophy and apoptosis, and it may exert these effects in part by suppressing ROS production and activating the PI3K/AKT signaling pathway.

Human Nitric Oxide Synthase-Its Functions, Polymorphisms, and Inhibitors in the Context of Inflammation, Diabetes and Cardiovascular Diseases

In various diseases, there is an increased production of the free radicals needed to carry out certain physiological processes but their excessive amounts can cause oxidative stress and cell damage. Enzymes play a major role in the transformations associated with free radicals. One of them is nitric oxide synthase (NOS), which catalyzes the formation of nitric oxide (NO). This enzyme exists in three forms (NOS1, NOS2, NOS3), each encoded by a different gene. The following work presents the most important information on the NOS isoforms and their role in the human body, including NO synthesis in various tissues and cells, intercellular signaling and activities supporting the immune system and regulating blood vessel functions. The role of NOS in pathological conditions such as obesity, diabetes and heart disease is considered. Attention is also paid to the influence of the polymorphisms of these genes, encoding particular isoforms, on the development of these pathologies and the role of NOS inhibitors in the treatment of patients.

Chronic Metabolic Acidosis Elicits Hypertension via Upregulation of Intrarenal Angiotensin II and Induction of Oxidative Stress

Chronic metabolic acidosis (CMA) can be a consequence of persistent hypertension but could potentially play a role in invoking hypertension. Currently, there is a scarcity of studies examining the outcome of induced chronic acidosis on blood pressure regulation. This study investigates CMA as a cause of hypertension. Chronic acidosis was induced in Sprague Dawley rats (100–150 g) by providing a weak acid solution of 0.28 M ammonium chloride (NH₄Cl) in tap water for 8 weeks. To determine whether the rats were acidotic, blood pH was measured, while blood pressure (BP) was monitored by tail-cuff plethysmography weekly. Rats were divided into five groups: control, CMA, CMA ± spironolactone, captopril, and tempol. Serum sodium and potassium; renal interstitial fluid (for Angiotensin II concentration); and kidney proximal tubules (for Na⁺/K⁺ ATPase- α1 concentration) were analyzed. Reactive oxygen species (ROS) were detected in renal cortical homogenates using electron paramagnetic resonance (EPR). In the CMA rats, a sustained elevation in mean arterial pressure (MAP) associated with a significant decrease in blood pH was observed compared to that of control over the 8 weeks. A significant decrease in MAP was observed in acidotic rats treated with captopril/tempol, whereas spironolactone treatment caused no decrease in MAP as compared to that of the CMA group. The interstitial angiotensin II was increased in the CMA group but decreased in the CMA with captopril and tempol groups. In addition, the urinary sodium was decreased, and the serum sodium levels increased significantly in the CMA groups as compared to that of control. However, the acidotic groups with captopril and tempol showed reduced levels of serum sodium and an elevation in urinary sodium as compared to that of the CMA group. In addition, there was a significant increase in plasma renin and no change in plasma aldosterone in the CMA group with no significant differences in plasma renin or aldosterone observed during spironolactone, captopril, or tempol treatments. The increased expression of Na⁺/K⁺ ATPase-α1 in the CMA group suggests that active transport of Na⁺ to the blood could be causative of the observed hypertension. Furthermore, the EPR analysis confirmed an elevation in superoxide (O₂^-) radical levels in the CMA group, but the tempol/captopril treated acidotic groups showed less (O₂^-) compared to that of either the CMA group or control. Taken together, our data suggest that induction of CMA could potentially be causative of hypertension, while the mechanisms underlying the increased BP could be through the activation of intrarenal Ang II and induction of oxidative stress.

Association between Light-Induced Dynamic Dilation of Retinal Vessels and Echocardiographic Parameters of the Left Ventricular Function in Hypertensive Patients

Background and Objectives: The goal was to evaluate the association of dynamic retinal vessel analysis (DVA) with echocardiographic parameters assessing systolic and diastolic function of the left ventricle in hypertension (HT) patients with preserved left ventricle ejection fraction. Materials and Methods: This observational retrospective study recruited 36 patients with HT and 28 healthy controls. Retinal vessel diameter and reactions to flicker light were examined. Each patient was examined with echocardiography to assess left ventricular systolic and diastolic function. Results: Multivariate analysis revealed that hypertension was an independent factor associated with lower flicker-induced arterial vasodilatation (β = −0.31, p = 0.029). In the HT group, there was a significant positive association between left ventricular ejection fraction and flicker-induced arterial vasodilation (Rs = +0.31, p = 0.007). Additionally, end-diastolic left ventricular diameter negatively correlated with both arterial (Rs = −0.26, p = 0.02) and venous (Rs = −0.27, p = 0.02) flicker responses. Additionally, the echocardiographic characteristics of the left atrium (LA) remodeling in the course of HT, including the area of the LA and its antero-posterior dimension, were both negatively correlated with the arterial flicker response (Rs = −0.34, p = 0.003; Rs = −0.33, p = 0.004, respectively). From tissue Doppler parameters, the left ventricular filling index E/e’ negatively correlated with AVR (arteriovenous ratio) values (Rs = −0.36, p = 0.002). Conclusions: We revealed that systolic and diastolic function of the left ventricle in hypertensive patients is associated with retinal microvascular function.

Nutrition, Bioenergetics, and Metabolic Syndrome

According to the World Health Organization (WHO), the global nutrition report shows that whilst part of the world's population starves, the other part suffers from obesity and associated complications. A balanced diet counterparts these extreme conditions with the proper proportion, composition, quantity, and presence of macronutrients, micronutrients, and bioactive compounds. However, little is known on the way these components exert any influence on our health. These nutrients aiming to feed our bodies, our tissues, and our cells, first need to reach mitochondria, where they are decomposed into CO2 and H2O to obtain energy. Mitochondria are the powerhouse of the cell and mainly responsible for nutrients metabolism, but they are also the main source of oxidative stress and cell death by apoptosis. Unappropriated nutrients may support mitochondrial to become the Trojan horse in the cell. This review aims to provide an approach to the role that some nutrients exert on mitochondria as a major contributor to high prevalent Western conditions including metabolic syndrome (MetS), a constellation of pathologic conditions which promotes type II diabetes and cardiovascular risk. Clinical and experimental data extracted from in vitro animal and cell models further demonstrated in patients, support the idea that a balanced diet, in a healthy lifestyle context, promotes proper bioenergetic and mitochondrial function, becoming the best medicine to prevent the onset and progression of MetS. Any advance in the prevention and management of these prevalent complications help to face these challenging global health problems, by ameliorating the quality of life of patients and reducing the associated sociosanitary burden.

Redox Imbalances in Ageing and Metabolic Alterations: Implications in Cancer and Cardiac Diseases. An Overview from the Working Group of Cardiotoxicity and Cardioprotection of the Italian Society of Cardiology (SIC)

Metabolic syndrome (MetS) is a well established risk factor for cardiovascular (CV) diseases. In addition, several studies indicate that MetS correlates with the increased risk of cancer in adults. The mechanisms linking MetS and cancer are not fully understood. Several risk factors involved in MetS are also cancer risk factors, such as the consumption of high calorie-food or high fat intake, low fibre intake, and sedentary lifestyle. Other common aspects of both cancer and MetS are oxidative stress and inflammation. In addition, some anticancer treatments can induce cardiotoxicity, including, for instance, left ventricular (LV) dysfunction and heart failure (HF), endothelial dysfunction and hypertension. In this review, we analyse several aspects of MetS, cancer and cardiotoxicity from anticancer drugs. In particular, we focus on oxidative stress in ageing, cancer and CV diseases, and we analyse the connections among CV risk factors, cancer and cardiotoxicity from anticancer drugs.

Oxidative Stress Markers Differ in Two Placental Dysfunction Pathologies: Pregnancy-Induced Hypertension and Intrauterine Growth Restriction

Aim

Pregnancy-induced hypertension (PIH) and intrauterine growth restriction (IUGR) are both multisystemic disorders of pregnancy that cause perinatal morbidity and mortality. Recently, researchers focused on the role of oxidative stress (OS) as a pathophysiological mechanism in the development of these pathologies. The aim of this study was to compare OS in placental-related pathologies (PIH and IUGR) and uncomplicated pregnancies. We also investigated which salivary OS markers reflect systemic oxidative status and which only reflect the state of the oral cavity. Material and Methods. A total of 104 pregnant women (n = 104; 27 with PIH, 30 with IUGR, and 47 controls) were evaluated. Malondialdehyde (MDA), total antioxidant capacity (ORAC), aldehyde dehydrogenase (ALDH), and activity of glutathione peroxidase (GPx) and glutathione transferase (GST) in plasma/whole blood and/or saliva were analysed. Dietary nutrient intake was calculated using a Semiquantitative Food Frequency Questionnaire (SFFQ). Oral health was assessed to eliminate patients with bleeding, severe periodontitis, and other dental pathologies.

Results

In the IUGR group, increased concentration of ORAC was observed both in saliva and plasma. Also, lower plasma levels of MDA in IUGR compared to the control group was detected. No sign of oxidative stress was confirmed in the PIH group. The examined groups did not differ regarding diet and markers of inflammation. ORAC in saliva was correlated with its level in plasma. No such correlations for MDA were observed. In the IUGR group, there were no differences in OS markers in plasma, but there was a lower ALDH level in the blood compared to the control group. It confirms OS occurrence in IUGR. In IUGR, a higher activity of salivary ALDH was probably due to worse oral health.

Conclusion

Oxidative stress differs between IUGR and PIH groups: the presence of oxidative stress was confirmed only in the IUGR group. Salivary ORAC can be used to estimate ORAC in plasma. The activity of salivary ALDH reflects the state of the oral cavity.

Engineering blood outgrowth endothelial cells to optimize endothelial nitric oxide synthase and extracellular matrix production for coating of blood contacting surfaces

Coverage of blood contacting surfaces by a functional endothelial layer is likely required to induce and maintain homeostasis. Blood outgrowth endothelial cells (BOECs), cultured from human peripheral blood monocytes, are readily available and functional autologous endothelial source that may represent a reasonable alternative to vascular derived cells. Endothelial nitric oxide synthase (eNOS) produces NO, an important factor that regulates homeostasis at the blood-contacting surface. We found that BOECs express markedly lower levels of eNOS protein (34% ± 13%, Western blot) and mRNA (29% ± 17%, qRT-PCR), as well as exhibiting reduced activity (49% ± 18%, Nitrite analysis) when compared to human umbilical vein endothelial cells (HUVECs) and human aortic endothelial cells. HUVECs grown on fibronectin, type I collagen, or laminin -coated surfaces exhibited significant reduction of eNOS mRNA and protein expression. However, no decrease in eNOS levels was observed in BOECs. Interestingly BOECs expressed significantly higher Collagen (Col) I compared to HUVECs, and blocking Col I synthesis significantly enhanced eNOS expression in BOECs. Inhibition of β1 integrin, focal adhesion kinase (FAK), or actin polymerization increased eNOS in both BOECs and HUVECs suggesting involvement of a signaling pathway culminating in stabilization of the cytoskeleton. Finally, we demonstrated that a Rho-associated protein kinases (ROCK) inhibitor, as a disruptor of actin stabilization, enhanced both eNOS expression and bioactivity. Taken together, our findings demonstrate that cell-ECM interactions are fundamental to the regulation of eNOS in BOECs and suggest that disruption of key intracellular pathways (such as ROCK) may be necessary to enhance functional activity of an endothelialized surface. STATEMENT OF SIGNIFICANCE: Development of biocompatible blood-contacting biomaterial surfaces has not been possible to date, leading many investigators to believe that a complete autologous endothelial layer will be necessary. Blood outgrowth endothelial cells (BOECs), cultured from human peripheral blood monocytes, are readily available and functional autologous endothelial source. Endothelial nitric oxide synthase (eNOS) produces NO, an important factor that regulates homeostasis at the blood-contacting surface. In this study, we show that eNOS displays limited expression in cultured BOECs. We further demonstrate that a strong negative regulation of eNOS is mediated by collagen substrates and that treatment with ROCK inhibitor could enhance both eNOS expression and activity in BOECs and help to rapidly establish a functional autologous endothelial layer on cardiovascular biomaterials.

Ischemic injury precipitates neuronal vulnerability in Parkinson's disease: Insights from PINK1 mouse model study and clinical retrospective data

INTRODUCTION

Increasing evidence demonstrates the relevant association between Parkinson's disease (PD) and vascular diseases/risk factors, as well as a worse clinico-pathological progression in those patients with vascular comorbidity. The mechanisms underlying this relationship have not been clarified yet, although their comprehension is critical in a perspective of disease-modifying treatments development or prevention.

METHODS

We performed an experimental protocol of ischemic injury (glucose-oxygen deprivation, OGD) on PTEN-induced kinase 1 knockout (PINK1^-/-) mice, a well-established PD model, looking at both electrophysiological and morphological changes in basal ganglia. In addition, 253 PD patients were retrospectively analysed, to estimate the prevalence of vascular risk factors.

RESULTS

In PINK1^-/- mice, the OGD protocol induced electrophysiological (prolonged depolarization) and morphological alterations (picnotic cells, cellular loss and swelling, thickening of nuclear chromatin) in striatal medium spiny neurons and nigral dopaminergic neurons. Vascular comorbidity occurred in 75% of PD patients.

CONCLUSIONS

The ischemic injury precipitates neuronal vulnerability in basal ganglia of PINK1^-/- mice, probably through an impairment of mitochondrial metabolism and higher oxidative stress. These experimental data may provide a potential mechanistic explanation for both the association between vascular diseases and PD and their reciprocal interactions in determining the clinico-pathological burden of PD patients.

Role of Mitophagy in Cardiovascular Disease

Cardiovascular disease is the leading cause of mortality worldwide, and mitochondrial dysfunction is the primary contributor to these disorders. Recent studies have elaborated on selective autophagy-mitophagy, which eliminates damaged and dysfunctional mitochondria, stabilizes mitochondrial structure and function, and maintains cell survival and growth. Numerous recent studies have reported that mitophagy plays an important role in the pathogenesis of various cardiovascular diseases. This review summarizes the mechanisms underlying mitophagy and advancements in studies on the role of mitophagy in cardiovascular disease.