Vascular Generation of Tumor Necrosis Factor-α Reduces Nitric Oxide Availability in Small Arteries From Visceral Fat of Obese Patients

Juvenile primary hypertension is associated with attenuated macro- and microvascular dilator function independently of body weight

OBJECTIVE

Hypertension has become a global medical and public health issue even in childhood. It is well accepted that hypertension is associated with impaired endothelium-dependent vascular reactivity in adult patients. However, there is a lack of data on hypertension-related endothelial dysfunction in hypertensive children. Thus, present study aimed to evaluate the association of primary hypertension in the pediatric population with macro- and microvascular function, and to assess the potential role of oxidative stress in that connection.

METHODS

Fifty-two children were enrolled in this study; 26 normotensive (NT) and 26 with primary hypertension (HT), both sexes, 9-17 years old. In addition to anthropometric, hemodynamic and biochemical measurements, peripheral microvascular responses to occlusion (postocclusive reactive hyperemia, PORH), local heating (local thermal hyperemia, LTH), iontophoretically applied acetylcholine (AChID) and sodium nitroprusside (SNPID) were evaluated by laser Doppler flowmetry (LDF). Furthermore, brachial artery flow-mediated dilation (FMD) was measured and biomarker of oxidative stress was determined.

RESULTS

PORH, AChID and LTH were impaired in hypertensive compared to normotensive children, while SNPID did not differ between groups. FMD was decreased in hypertensive compared to normotensive children. Serum concentration of 8- iso -PGF2α was significantly elevated in hypertensive compared to normotensive children.

CONCLUSION

Even in childhood, primary hypertension is associated with attenuated endothelial function and reduced endothelium-dependent responses to various physiological stimuli. Juvenile hypertension is related to increased level of vascular oxidative stress. All changes are independent of BMI.

Usefulness of the ECORE-BF Scale to Determine Atherogenic Risk in 386,924 Spanish Workers

BACKGROUND

Cardiovascular diseases are the leading cause of death worldwide. Obesity and atherosclerosis are considered risk factors for this pathology. There are multiple methods to evaluate obesity, in the same way as there are different formulas to determine atherogenic risk. Since both pathologies are closely related, the objective of our work was to evaluate whether the ECORE-BF scale is capable of predicting atherogenic risk.

METHODS

Observational, descriptive, and cross-sectional study in which 386,924 workers from several autonomous communities in Spain participated. The association between the ECORE-BF scale and five atherogenic risk indices was evaluated. The relationship between variables was assessed using the chi-square test and Student's t test in independent samples. Multivariate analysis was performed with the multinomial logistic regression test, calculating the odds ratio and 95% confidence intervals, with the Hosmer-Lemeshow goodness-of-fit test. ROC curves established the cut-off points for moderate and high vascular age and determined the Youden index.

RESULTS

The mean values of the ECORE-BF scale were higher in individuals with atherogenic dyslipidemia and the lipid triad, as well as in those with elevated values of the three atherogenic indices studied, with p <0.001 in all cases. As atherogenic risk increased across the five evaluated scales, the prevalence of obesity also significantly increased, with p <0.001 in all cases. In the ROC curve analysis, the AUCs for atherogenic dyslipidemia and the lipid triad were above 0.75, indicating a good association between these scales and the ECORE-BF. Although the Youden indices were not exceedingly high, they were around 0.5.

CONCLUSIONS

There is a good association between atherogenic risk scales, atherogenic dyslipidemia, and lipid triad, and the ECORE-BF scale. The ECORE-BF scale can be a useful and quick tool to evaluate atherogenic risk in primary care and occupational medicine consultations without the need for blood tests.

Endothelial Dysfunction in Obesity and Therapeutic Targets

Parallel to the increasing prevalence of obesity in the world, the mortality from cardiovascular disease has also increased. Low-grade chronic inflammation in obesity disrupts vascular homeostasis, and the dysregulation of adipocyte-derived endocrine and paracrine effects contributes to endothelial dysfunction. Besides the adipose tissue inflammation, decreased nitric oxide (NO)-bioavailability, insulin resistance (IR), and oxidized low-density lipoproteins (oxLDLs) are the main factors contributing to endothelial dysfunction in obesity and the development of cardiorenal metabolic syndrome. While normal healthy perivascular adipose tissue (PVAT) ensures the dilation of blood vessels, obesity-associated PVAT leads to a change in the profile of the released adipo-cytokines, resulting in a decreased vasorelaxing effect. Higher stiffness parameter β, increased oxidative stress, upregulation of pro-inflammatory cytokines, and nicotinamide adenine dinucleotide phosphate (NADP) oxidase in PVAT turn the macrophages into pro-atherogenic phenotypes by oxLDL-induced adipocyte-derived exosome-macrophage crosstalk and contribute to the endothelial dysfunction. In clinical practice, carotid ultrasound, higher leptin levels correlate with irisin over-secretion by human visceral and subcutaneous adipose tissues, and remnant cholesterol (RC) levels predict atherosclerotic disease in obesity. As a novel therapeutic strategy for cardiovascular protection, liraglutide improves vascular dysfunction by modulating a cyclic adenosine monophosphate (cAMP)-independent protein kinase A (PKA)-AMP-activated protein kinase (AMPK) pathway in PVAT in obese individuals. Because the renin-angiotensin-aldosterone system (RAAS) activity, hyperinsulinemia, and the resultant IR play key roles in the progression of cardiovascular disease in obesity, RAAS-targeted therapies contribute to improving endothelial dysfunction. By contrast, arginase reciprocally inhibits NO formation and promotes oxidative stress. Thus, targeting arginase activity as a key mediator in endothelial dysfunction has therapeutic potential in obesity-related vascular comorbidities. Obesity-related endothelial dysfunction plays a pivotal role in the progression of type 2 diabetes (T2D). The peroxisome proliferator-activated receptor gamma (PPARγ) agonist, rosiglitazone (thiazolidinedione), is a popular drug for treating diabetes; however, it leads to increased cardiovascular risk. Selective sodium-glucose co-transporter-2 (SGLT-2) inhibitor empagliflozin (EMPA) significantly improves endothelial dysfunction and mortality occurring through redox-dependent mechanisms. Although endothelial dysfunction and oxidative stress are alleviated by either metformin or EMPA, currently used drugs to treat obesity-related diabetes neither possess the same anti-inflammatory potential nor simultaneously target endothelial cell dysfunction and obesity equally. While therapeutic interventions with glucagon-like peptide-1 (GLP-1) receptor agonist liraglutide or bariatric surgery reverse regenerative cell exhaustion, support vascular repair mechanisms, and improve cardiometabolic risk in individuals with T2D and obesity, the GLP-1 analog exendin-4 attenuates endothelial endoplasmic reticulum stress.

The Role of Perivascular Adipose Tissue in the Pathogenesis of Endothelial Dysfunction in Cardiovascular Diseases and Type 2 Diabetes Mellitus

Cardiovascular diseases (CVDs) and type 2 diabetes mellitus (T2DM) are two of the four major chronic non-communicable diseases (NCDs) representing the leading cause of death worldwide. Several studies demonstrate that endothelial dysfunction (ED) plays a central role in the pathogenesis of these chronic diseases. Although it is well known that systemic chronic inflammation and oxidative stress are primarily involved in the development of ED, recent studies have shown that perivascular adipose tissue (PVAT) is implicated in its pathogenesis, also contributing to the progression of atherosclerosis and to insulin resistance (IR). In this review, we describe the relationship between PVAT and ED, and we also analyse the role of PVAT in the pathogenesis of CVDs and T2DM, further assessing its potential therapeutic target with the aim of restoring normal ED and reducing global cardiovascular risk.

The importance of microvascular inflammation in ageing and age-related diseases: a position paper from the ESH working group on small arteries, section of microvascular inflammation

Microcirculation is pervasive and orchestrates a profound regulatory cross-talk with the surrounding tissue and organs. Similarly, it is one of the earliest biological systems targeted by environmental stressors and consequently involved in the development and progression of ageing and age-related disease. Microvascular dysfunction, if not targeted, leads to a steady derangement of the phenotype, which cumulates comorbidities and eventually results in a nonrescuable, very high-cardiovascular risk. Along the broad spectrum of pathologies, both shared and distinct molecular pathways and pathophysiological alteration are involved in the disruption of microvascular homeostasis, all pointing to microvascular inflammation as the putative primary culprit. This position paper explores the presence and the detrimental contribution of microvascular inflammation across the whole spectrum of chronic age-related diseases, which characterise the 21st-century healthcare landscape. The manuscript aims to strongly affirm the centrality of microvascular inflammation by recapitulating the current evidence and providing a clear synoptic view of the whole cardiometabolic derangement. Indeed, there is an urgent need for further mechanistic exploration to identify clear, very early or disease-specific molecular targets to provide an effective therapeutic strategy against the otherwise unstoppable rising prevalence of age-related diseases.

The renal resistive index is associated with microvascular remodeling in patients with severe obesity

BACKGROUND

Renal hemodynamics is impaired since the early stage of cardiometabolic disease. However, in obesity, its noninvasive ultrasound assessment still fails to provide pathophysiologic and clinical meaningfulness. We aimed to explore the relationship between peripheral microcirculation and renal hemodynamics in severe obesity.

METHODS

We enrolled fifty severely obese patients with an indication for bariatric referring to our outpatient clinic. Patients underwent an extensive reno-metabolic examination, paired with Doppler ultrasound and measurement of the renal resistive index (RRI). On the day of the surgery, visceral fat biopsies were collected to perform an ex-vivo complete microcirculatory assessment. Media-to-lumen ratio (M/L) and vascular response to acetylcholine (ACh), alone or co-incubated with N G -nitro arginine methyl ester (L-NAME), were measured.

RESULTS

Patients were stratified according to their normotensive (NT) or hypertensive (HT) status. HT had lower estimated glomerular filtration rate and higher RRI compared to NT, while the presence and extent of albuminuria were similar between the two groups. Concerning microcirculatory assessment, there were no differences between groups as regards the microvascular structure, while the vasorelaxation to ACh was lower in HT ( P = 0.042). Multivariable analysis showed a relationship between M/L and RRI ( P  = 0.016, St. β 0.37) and between albuminuria and the inhibitory response of L-NAME to Ach vasodilation ( P   =  0.036, St. β = -0.34). Notably, all these correlations were consistent also after adjustment for confounding factors.

CONCLUSIONS

The RRI and albuminuria relationship with microvascular remodeling in patients affected by severe obesity supports the clinical implementation of RRI to improve risk stratification in obesity and suggests a tight pathophysiologic connection between renal haemodynamics and microcirculatory disruption.

Obesity-Induced Coronary Microvascular Disease Is Prevented by iNOS Deletion and Reversed by iNOS Inhibition

Coronary microvascular disease (CMD) caused by obesity and diabetes is major contributor to heart failure with preserved ejection fraction; however, the mechanisms underlying CMD are not well understood. Using cardiac magnetic resonance applied to mice fed a high-fat, high-sucrose diet as a model of CMD, we elucidated the role of inducible nitric oxide synthase (iNOS) and 1400W, an iNOS antagonist, in CMD. Global iNOS deletion prevented CMD along with the associated oxidative stress and diastolic and subclinical systolic dysfunction. The 1400W treatment reversed established CMD and oxidative stress and preserved systolic/diastolic function in mice fed a high-fat, high-sucrose diet. Thus, iNOS may represent a therapeutic target for CMD.

Synthesis and Characterization of Fucoidan-Chitosan Nanoparticles Targeting P-Selectin for Effective Atherosclerosis Therapy

Atherosclerosis is the key pathogenesis of cardiovascular diseases; oxidative stress, which is induced by the generated excess reactive oxygen species (ROS), has been a crucial mechanism underlying this pathology. Nanoparticles (NPs) represent a novel strategy for the development of potential therapies against atherosclerosis, and multifunctional NPs possessing antioxidative capacities hold promise for amelioration of vascular injury caused by ROS and for evading off-target effects; materials that are currently used for NP synthesis often serve as vehicles that do not possess intrinsic biological activities; however, they may affect the surrounding healthy environment due to decomposition of products. Herein, we used nontoxic fucoidan, a sulfated polysaccharide derived from a marine organism, to develop chitosan–fucoidan nanoparticles (CFNs). Then, by binding to P-selectin, an inflammatory adhesion exhibited molecule expression on the endothelial cells and activated platelets, blocking leukocyte recruitment and rolling on platelets and endothelium. CFNs exhibit antioxidant and anti-inflammatory properties. Nevertheless, by now, the application of CFNs for the target delivery regarding therapeutics specific to atherosclerotic plaques is not well investigated. The produced CFNs were physicochemically characterized using transmission electron microscopy (TEM), together with Fourier transform infrared spectroscopy (FTIR). Evaluations of the in vitro antioxidant as well as anti-inflammatory activities exhibited by CFNs were based on the measurement of their ROS scavenging abilities and investigating inflammatory mediator levels. The in vivo pharmacokinetics and binding efficiency of the CFNs to atherosclerotic plaques were also evaluated. The therapeutic effects indicated that CFNs effectively suppressed local oxidative stress and inflammation by targeting P-selectin in atheromatous plaques and thereby preventing the progression of atherosclerosis.

Targeting SIRT1 Rescues Age- and Obesity-Induced Microvascular Dysfunction in Ex Vivo Human Vessels

BACKGROUND

Experimental evidence suggests a key role of SIRT1 (silent information regulator 1) in age- and metabolic-related vascular dysfunction. Whether these effects hold true in the human microvasculature is unknown. We aimed to investigate the SIRT1 role in very early stages of age- and obesity-related microvascular dysfunction in humans.

METHODS

Ninety-five subjects undergoing elective laparoscopic surgery were recruited and stratified based on their body mass index status (above or below 30 kg/m²) and age (above or below 40 years) in 4 groups: Young Nonobese, Young Obese, Old Nonobese, and Old Obese. We measured small resistance arteries' endothelial function by pressurized micromyography before and after incubation with a SIRT1 agonist (SRT1720) and a mitochondria reactive oxygen species (mtROS) scavenger (MitoTEMPO). We assessed vascular levels of mtROS and nitric oxide availability by confocal microscopy and vascular gene expression of SIRT1 and mitochondrial proteins by qPCR. Chromatin immunoprecipitation assay was employed to investigate SIRT1-dependent epigenetic regulation of mitochondrial proteins.

RESULTS

Compared with Young Nonobese, obese and older patients showed lower vascular expression of SIRT1 and antioxidant proteins (FOXO3 [forkhead box protein O3] and SOD2) and higher expression of pro-oxidant and aging mitochondria proteins p66^Shc and Arginase II. Old Obese, Young Obese and Old Nonobese groups endothelial dysfunction was rescued by SRT1720. The restoration was comparable to the one obtained with mitoTEMPO. These effects were explained by SIRT1-dependent chromatin changes leading to reduced p66^Shc expression and upregulation of proteins involved in mitochondria respiratory chain.

CONCLUSIONS

SIRT1 is a novel central modulator of the earliest microvascular damage induced by age and obesity. Through a complex epigenetic control mainly involving p66^Shc and Arginase II, it influences mtROS levels, NO availability, and the expression of proteins of the mitochondria respiratory chain. Therapeutic modulation of SIRT1 restores obesity- and age-related endothelial dysfunction. Early targeting of SIRT1 might represent a crucial strategy to prevent age- and obesity-related microvascular dysfunction.

Association Between Triglyceride-Glucose Index and 2-Year Adverse Cardiovascular and Cerebrovascular Events in Patients with Type 2 Diabetes Mellitus Who Underwent Off-Pump Coronary Artery Bypass Grafting

BACKGROUND

Data on the relationship between the triglyceride glucose (TyG) index and prognosis after off-pump coronary artery bypass grafting (OPCABG) are limited. This retrospective observational cohort study evaluated the association of the TyG index with prognosis in patients with diabetes mellitus who underwent OPCABG.

METHODS

The TyG index was calculated using the following equation: TyG index = ln (fasting triglyceride level [mg/dL] × fasting glucose level [mg/dL]/2). The primary outcomes included the occurrence of major adverse cardiovascular and cerebrovascular events (MACCEs), which were defined as all-cause death, nonfatal myocardial infarction, nonfatal stroke and symptomatic graft failure. The association between the TyG index and MACCEs was assessed by Cox proportional hazards regression analysis.

RESULTS

A total of 1578 patients with diabetes who underwent OPCABG (mean age, 62.9 ± 8.0 years; men, 72.7%) were enrolled in this study. Over the follow-up of 2 years, 176 patients (11.2%) had at least 1 primary endpoint event. The follow-up incidence of the primary endpoint rose with increasing TyG index tertiles. The multivariate Cox proportional hazards regression analysis adjusted for multiple confounders revealed a hazard ratio for the primary endpoint of 2.133 (95% CI 1.347-3.377; P for trend = 0.001) when the highest and lowest TyG index tertiles were compared.

CONCLUSION

The TyG index was significantly and positively associated with MACCEs, suggesting that the TyG index may be a valuable predictor of adverse cardiovascular and cerebrovascular outcomes after OPCABG in patients with T2DM.

Etanercept Prevents Endothelial Dysfunction in Cafeteria Diet-Fed Rats

Obesity is associated with endothelial dysfunction and this relationship is probably mediated in part by inflammation. Objective: The current study evaluated the effects of etanercept, a tumor necrosis factor-alpha (TNF-α) inhibitor, on endothelial and vascular reactivity, endothelial nitric oxide synthase (eNOS) immunoreactivity, and serum and aortic concentrations of TNF-α in a diet-induced rat model. Design and results: Male weanling Wistar rats were exposed to a standard diet and cafeteria diet (CD) for 12 weeks and etanercept was administered during CD treatment. Isolated aortas of the rats were used for isometric tension recording. Carbachol-induced relaxant responses were impaired in CD-fed rats, while etanercept treatment improved these endothelium-dependent relaxations. No significant change was observed in papaverine- and sodium nitroprusside (SNP)-induced relaxant responses. eNOS expression decreased in CD-fed rats, but no change was observed between etanercept-treated CD-fed rats and control rats. CD significantly increased both the serum and the aortic levels of TNF-α, while etanercept treatment suppressed these elevated levels. CD resulted in a significant increase in the body weight of the rats. Etanercept-treated (ETA) CD-fed rats gained less weight than both CD-fed and control rats.

Microvascular Inflammation and Cardiovascular Prevention: The Role of Microcirculation as Earlier Determinant of Cardiovascular Risk

Healthcare systems encumbered by cardiovascular diseases demand adequate cardiovascular prevention. Indeed, even with the most novel therapies, the residual cardiovascular risk still fuels morbidity and mortality. Addressing inflammation as a putative mediator of this risk has brought along promising in vitro results, though large clinical trials have only in part confirmed them. To fully exploit the therapeutic potential between the inflammatory hypothesis, a change of viewpoint is required. Focus on microcirculation, whose dysfunction is the primary driver of cardiometabolic disease, is mandatory. Several factors play a pivotal role in the capacity of microvascular inflammation to promote a health-to-disease transition: the adipose tissue (in particular, perivascular and epicardial), the mitochondria function, the hyperglycemic damage and their epigenetic signature. Indeed, the low-grade inflammatory response, which is now an acknowledged hallmark of cardiometabolic disease, is promoted by these mediators and leaves a permanent epigenetic scar on the microvasculature. Even if a more profound knowledge about the mechanisms of metabolic memory has been brought to light by recent evidence, we still have to fully understand its mechanisms and clinical potential. Addressing the detrimental role of inflammation by targeting the microvascular phenotype and leveraging epigenetics is the road down which we must go to achieve satisfactory cardiovascular prevention, ultimately leading to disease-free ageing.

Vasodilator Dysfunction in Human Obesity: Established and Emerging Mechanisms

ABSTRACT

Human obesity is associated with insulin resistance and often results in a number of metabolic abnormalities and cardiovascular complications. Over the past decades, substantial advances in the understanding of the cellular and molecular pathophysiological pathways underlying the obesity-related vascular dysfunction have facilitated better identification of several players participating in this abnormality. However, the complex interplay between the disparate mechanisms involved has not yet been fully elucidated. Moreover, in medical practice, the clinical syndromes stemming from obesity-related vascular dysfunction still carry a substantial burden of morbidity and mortality; thus, early identification and personalized clinical management seem of the essence. Here, we will initially describe the alterations of intravascular homeostatic mechanisms occurring in arteries of obese patients. Then, we will briefly enumerate those recognized causative factors of obesity-related vasodilator dysfunction, such as vascular insulin resistance, lipotoxicity, visceral adipose tissue expansion, and perivascular adipose tissue abnormalities; next, we will discuss in greater detail some emerging pathophysiological mechanisms, including skeletal muscle inflammation, signals from gut microbiome, and the role of extracellular vesicles and microRNAs. Finally, it will touch on some gaps in knowledge, as well as some current acquisitions for specific treatment regimens, such as glucagon-like peptide-1 enhancers and sodium-glucose transporter2 inhibitors, that could arrest or slow the progression of this abnormality full of unwanted consequences.

Microvascular Ageing Links Metabolic Disease to Age-Related Disorders: The Role of Oxidative Stress and Inflammation in Promoting Microvascular Dysfunction

ABSTRACT

Longer life span and increased prevalence of chronic, noncommunicable, inflammatory diseases fuel cardiovascular mortality. The microcirculation is central in the cross talk between ageing, inflammation, cardiovascular, and metabolic diseases. Microvascular dysfunction, characterized by alteration in the microvascular endothelial function and wall structure, is described in an increasing number of chronic age-associated diseases, suggesting that it might be a marker of ageing superior to chronological age. The aim of this review is to thoroughly explore the connections between microvascular dysfunction, ageing, and metabolic disorders by detailing the major role played by inflammation and oxidative stress in their evolution. Older age, hypertension, nutrient abundance, and hyperglycemia concur in the induction of a persistent low-grade inflammatory response, defined as meta-inflammation or inflammageing. This increases the local generation of reactive oxygen species that further impairs endothelial function and amplifies the local inflammatory response. Mitochondrial dysfunction is a hallmark of many age-related diseases. The alterations of mitochondrial function promote irreversible modification in microvascular structure. The interest in the hypothesis of chronic inflammation at the center of the ageing process lies in its therapeutic implications. Inhibition of specific inflammatory pathways has been shown to lower the risk of many age-related diseases, including cardiovascular disease. However, the whole architecture of the inflammatory response underpinning the ageing process and its impact on the burden of age-related diseases remain to be fully elucidated. Additional studies are needed to unravel the connection between these biological pathways and to address their therapeutic power in terms of cardiovascular prevention.

Interactions Between Specific Immune Status of Pregnant Women and SARS-CoV-2 Infection

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the pathogen responsible for the Coronavirus Disease 2019 (COVID-19) global pandemic. Because it is a new and highly contagious coronavirus, most people, especially pregnant women, lack immunity. It is therefore important to understand the interaction between why pregnant women are susceptible to SARS-CoV-2 and the specific immune systems of pregnant women. Here, we provide an overview of the changes that occur in the immune system during pregnancy, the activation and response of the immune system in pregnant women with COVID-19, adverse pregnancy outcomes in pregnant women with COVID-19, and the treatment and prevention of COVID-19 in this population.

Assessment and pathophysiology of microvascular disease: recent progress and clinical implications

The development of novel, non-invasive techniques and standardization of protocols to assess microvascular dysfunction have elucidated the key role of microvascular changes in the evolution of cardiovascular (CV) damage, and their capacity to predict an increased risk of adverse events. These technical advances parallel with the development of novel biological assays that enabled the ex vivo identification of pathways promoting microvascular dysfunction, providing novel potential treatment targets for preventing cerebral-CV disease. In this article, we provide an update of diagnostic testing strategies to detect and characterize microvascular dysfunction and suggestions on how to standardize and maximize the information obtained from each microvascular assay. We examine emerging data highlighting the significance of microvascular dysfunction in the development CV disease manifestations. Finally, we summarize the pathophysiology of microvascular dysfunction emphasizing the role of oxidative stress and its regulation by epigenetic mechanisms, which might represent potential targets for novel interventions beyond conventional approaches, representing a new frontier in CV disease reduction.

Ethyl Acetate Fraction and Isolated Phenolics Derivatives from Mandevilla moricandiana Identified by UHPLC-DAD-ESI-MSn with Pharmacological Potential for the Improvement of Obesity-Induced Endothelial Dysfunction

Endothelial dysfunction in obesity plays a key role in the development of cardiovascular diseases, and it is characterized by increased vascular tonus and oxidative stress. Thus, this study aimed to investigate the vasodilatory and antioxidant activities of Mandevilla moricandiana ethyl acetate fraction and subfractions. Vascular effects were investigated on aorta isolated from control and monosodium glutamate (MSG) induced-obese Wistar rats, and antioxidant activity was assessed by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and oxygen radical absorbance capacity (ORAC) methods. The ethyl acetate fraction (MMEAF) induced a concentration-dependent vasodilation on aortic rings through the NO pathway, with the involvement of histamine H1 and estrogen ERα receptors and showed potent antioxidant activity. In aorta of MSG obese rats, maximal relaxation to acetylcholine was increased in the presence of MMEAF (3 µg/mL), indicating that MMEAF ameliorated obesity-induced endothelial dysfunction. Quercetin and kaempferol aglycones and their correspondent glycosides, as well as caffeoylquinic acid derivatives, A-type procyanidin trimer, ursolic and oleanolic triterpenoid acids were identified in subfractions from MMEAF and seem to be the metabolites responsible for the vascular and antioxidant activities of this fraction.

JAK2 deficiency improves erectile function in diabetic mice through attenuation of oxidative stress, apoptosis, and fibrosis

Background

Janus kinase 2 (JAK2) is activated in diabetic mellitus (DM) conditions and may enhance oxidative stress, apoptosis and fibrosis in many tissues. Whether JAK2 activation is involved in the occurrence of diabetic erectile dysfunction (ED) is unknown.

Objectives

We performed this study to investigate the effect of JAK2 deficiency on diabetic ED.

Materials and methods

Conditional JAK2 gene knockout mice (Cre^+/+‐JAK2^fl/fl) were used, in which JAK2 gene knockout could be induced by tamoxifen. Mice fell into four groups: control, JAK2 knockout (JAK2^−/−), DM, and DM with JAK2^−/−. DM was induced by intraperitoneal injection of streptozotocin. Two months later, JAK2 gene knockout was induced with tamoxifen in Cre^+/+‐JAK2^fl/fl mice. After another 2 months, erectile function was measured by electrical stimulation of the cavernous nerve, and penile tissues were harvested. Ratio of maximal intracavernosal pressure (MIP) to mean arterial blood pressure (MAP), expression and phosphorylation of JAK2, oxidative stress level, NO/Cyclic Guanosine Monophosphate (cGMP) pathway, apoptosis, fibrosis, and transforming growth factor beta 1 (TGF‐β1)/Smad/Collagen IV pathway in corpus cavernosum, were measured.

Results

JAK2 expression was remarkably decreased after induction with tamoxifen. JAK2 was activated in penile tissues of diabetic mice, and JAK2 deficiency could improve the impaired erectile function caused by DM. However, in mice without DM, JAK2 deficiency had no apparent influence on erectile function. Levels of oxidative stress, apoptosis, fibrosis, and TGF‐β1/Smad/Collagen IV pathway were all elevated by DM, whereas JAK2 deficiency lessened these alterations in diabetic mice. Moreover, JAK2 deficiency improved the expression of the down‐regulated NO/cGMP pathway in diabetic mice. In non‐diabetic mice, no apparent changes were found in aforementioned parameters after JAK2 gene knockout.

Discussion and conclusion

Our study showed that JAK2 deficiency could improve erectile function in diabetic mice, which might be mediated by reduction in oxidative stress, apoptosis, and fibrosis in corpus cavernosum.

Epigenetic Remodeling in Obesity-Related Vascular Disease

Significance: The prevalence of obesity and cardiometabolic phenotypes is alarmingly increasing across the globe and is associated with atherosclerotic vascular complications and high mortality. In spite of multifactorial interventions, vascular residual risk remains high in this patient population, suggesting the need for breakthrough therapies. The mechanisms underpinning obesity-related vascular disease remain elusive and represent an intense area of investigation. Recent Advances: Epigenetic modifications-defined as environmentally induced chemical changes of DNA and histones that do not affect DNA sequence-are emerging as a potent modulator of gene transcription in the vasculature and might significantly contribute to the development of obesity-induced endothelial dysfunction. DNA methylation and histone post-translational modifications cooperate to build complex epigenetic signals, altering transcriptional networks that are implicated in redox homeostasis, mitochondrial function, vascular inflammation, and perivascular fat homeostasis in patients with cardiometabolic disturbances. Critical Issues: Deciphering the epigenetic landscape in the vasculature is extremely challenging due to the complexity of epigenetic signals and their function in regulating transcription. An overview of the most important epigenetic pathways is required to identify potential molecular targets to treat or prevent obesity-related endothelial dysfunction and atherosclerotic disease. This would enable the employment of precision medicine approaches in this setting. Future Directions: Current and future research efforts in this field entail a better definition of the vascular epigenome in obese patients as well as the unveiling of novel, cell-specific chromatin-modifying drugs that are able to erase specific epigenetic signals that are responsible for maladaptive transcriptional alterations and vascular dysfunction in obese patients. Antioxid. Redox Signal. 34, 1165-1199.

Cell-specific epigenetic changes in atherosclerosis

Atherosclerosis is a disease of large and medium arteries that can lead to life-threatening cerebrovascular and cardiovascular consequences such as heart failure and stroke and is a major contributor to cardiovascular-related mortality worldwide. Atherosclerosis development is a complex process that involves specific structural, functional and transcriptional changes in different vascular cell populations at different stages of the disease. The application of single-cell RNA sequencing (scRNA-seq) analysis has discovered not only disease-related cell-specific transcriptomic profiles but also novel subpopulations of cells once thought as homogenous cell populations. Vascular cells undergo specific transcriptional changes during the entire course of the disease. Epigenetics is the instruction-set-architecture in living cells that defines and maintains the cellular identity by regulating the cellular transcriptome. Although different cells contain the same genetic material, they have different epigenomic signatures. The epigenome is plastic, dynamic and highly responsive to environmental stimuli. Modifications to the epigenome are driven by an array of epigenetic enzymes generally referred to as writers, erasers and readers that define cellular fate and destiny. The reversibility of these modifications raises hope for finding novel therapeutic targets for modifiable pathological conditions including atherosclerosis where the involvement of epigenetics is increasingly appreciated. This article provides a critical review of the up-to-date research in the field of epigenetics mainly focusing on in vivo settings in the context of the cellular role of individual vascular cell types in the development of atherosclerosis.

Relationship between insulin resistance, coronary plaque, and clinical outcomes in patients with acute coronary syndromes: an analysis from the PROSPECT study

Background

We investigated the association of insulin resistance (IR) with coronary plaque morphology and the risk of cardiovascular events in patients enrolled in the Providing Regional Observations to Study Predictors of Events in Coronary Tree (PROSPECT) study.

Methods

Patients with acute coronary syndromes (ACS) were divided based on DM status. Non-DM patients were further stratified according to homeostasis-model-assessment IR (HOMA-IR) index as insulin sensitive (IS; HOMA-IR ≤ 2), likely-IR (LIR; 2 < HOMA-IR < 5), or diabetic-IR (DIR; HOMA-IR ≥ 5). Coronary plaque characteristics were investigated by intravascular ultrasound. The primary endpoint was major adverse cardiac events (MACE); a composite of cardiac death, cardiac arrest, myocardial infarction, and rehospitalization for unstable/progressive angina.

Results

Among non-diabetic patients, 109 patients (21.5%) were categorized as LIR, and 65 patients (12.8%) as DIR. Patients with DIR or DM had significantly higher rates of echolucent plaque compared with LIR and IS. In addition, DIR and DM were independently associated with increased risk of MACE compared with IS (adjusted hazard ratio [aHR] 2.29, 95% confidence interval [CI] 1.22–4.29, p = 0.01 and aHR 2.12, 95% CI 1.19–3.75, p = 0.009, respectively).

Conclusions

IR is common among patients with ACS. DM and advanced but not early stages of IR are independently associated with increased risk of adverse cardiovascular events.

Trial Registration ClinicalTrials.gov Identifier: NCT00180466.

Disentangling the epigenetic landscape in cardiovascular patients: a path toward personalized medicine

Despite significant advances in our understanding of cardiovascular disease (CVD) we are still far from having developed breakthrough strategies to combat coronary atherosclerosis and heart failure, which account for most of CV deaths worldwide. Available cardiovascular therapies have failed to show to be equally effective in all patients, suggesting that inter-individual diversity is an important factor when it comes to conceive and deliver effective personalized treatments. Genome mapping has proved useful in identifying patients who could benefit more from specific drugs depending on genetic variances; however, our genetic make-up determines only a limited part of an individual's risk profile. Recent studies have demonstrated that epigenetic changes - defined as dynamic changes of DNA and histones which do not affect DNA sequence - are key players in the pathophysiology of cardiovascular disease and may participate to delineate cardiovascular risk trajectories over the lifetime. Epigenetic modifications include changes in DNA methylation, histone modifications and non-coding RNAs and these epigenetic signals have shown to cooperate in modulating chromatin accessibility to transcription factors and gene expression. Environmental factors such as air pollution, smoking, psychosocial context, and unhealthy diet regimens have shown to significantly modify the epigenome thus leading to altered transcriptional programs and CVD phenotypes. Therefore, the integration of genetic and epigenetic information might be invaluable to build individual maps of cardiovascular risk and hence, could be employed for the design of customized diagnostic and therapeutic strategies. In the present review, we discuss the growing importance of epigenetic information and its putative implications in cardiovascular precision medicine.

Trans, trans-2,4-decadienal impairs vascular endothelial function by inducing oxidative/nitrative stress and apoptosis

Aldehydes are implicated in the development of hypertension. Trans, trans-2,4-decadienal (tt-DDE), a dietary α,β-unsaturated aldehyde, is widespread in many food products. However, the role of tt-DDE in the pathophysiology of hypertension remains unknown. This study was designed to investigate whether tt-DDE consumption evokes hypertension and to explore the mechanisms underlying such a role. Sprague-Dawley rats were administered different concentrations of tt-DDE. After 28 days, blood pressure and endothelial function of mesenteric arteries were measured. Results showed that tt-DDE treatment significantly increased blood pressure and impaired endothelial function based on endothelium-dependent vasorelaxation and p-VASP levels. Mechanistically, tt-DDE induced oxidative/nitrative stress in the arteries of rats as evidenced by overproductions of superoxide and peroxynitrite, accompanied with increased expressions of iNOS and gp91^phox. To further investigate the effects of tt-DDE on endothelial cells and underlying mechanisms, human umbilical vein endothelial cells (HUVECs) were treated with different concentrations of tt-DDE. tt-DDE induced oxidative/nitrative stress in HUVECs. Moreover, tt-DDE induced endothelial cells apoptosis through JNK-mediated signaling pathway. These results show, for the first time, that oral intake of tt-DDE elevates blood pressure and induces endothelial dysfunction in rats through oxidative/nitrative stress and JNK-mediated apoptosis signaling, indicating that excess ingestion of tt-DDE is a potential risk factor for endothelial dysfunction and hypertension.

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Trans, trans-2,4-decadienal (tt-DDE) is a dietary α,β-unsaturated aldehyde.

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tt-DDE raised blood pressure and impaired endothelial function in rats.

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Oxidative/nitrative stress was induced by tt-DDE in both rats and HUVECs.

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HUVEC apoptosis in response to tt-DDE exposure was mediated by JNK signaling.

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tt-DDE may be a risk factor for hypertension and associated cardiovascular disease.

Von Willebrand Factor Deficiency Improves Hepatic Steatosis, Insulin Resistance, and Inflammation in Mice Fed High-Fat Diet

OBJECTIVE

The aim of this study was to investigate the effect of Von Willebrand factor (VWF) on high-fat diet (HFD)-induced hepatic steatosis, insulin resistance, and inflammation in mice.

METHODS

The expression of VWF was detected in obese mice. Wild-type and VWF knockout mice were fed a normal chow diet or an HFD, and then biomedical, histological, and metabolic analyses were conducted to identify pathologic alterations. Inflammatory cytokine levels and the number of hepatic macrophages were determined in these mice fed an HFD.

RESULTS

VWF expression was significantly increased in obese mice. VWF^-/- mice were less obese and had improved hepatic steatosis, balance of lipid metabolism, and insulin resistance in response to HFD. Furthermore, VWF deficiency attenuated HFD-induced systemic and hepatic inflammation. In addition, VWF deficiency rescued the abnormal accumulation of hepatic macrophages.

CONCLUSIONS

These data demonstrated VWF deficiency improves hepatic steatosis, insulin resistance, and inflammation. Furthermore, the protective effects are mediated via regulation of hepatic macrophages.

Obesity, Metabolic Syndrome and the Risk of Microvascular Complications in Patients with Diabetes mellitus

BACKGROUND

Obesity frequently co-exists with type 2 diabetes mellitus (T2DM), leading to the socalled "diabesity epidemic". The metabolic syndrome (MetS), a cluster of central obesity, hypertension, dysglycemia, insulin resistance and/or atherogenic dyslipidemia, as well as non-alcoholic fatty liver disease (NAFLD), a hepatic manifestation of MetS, has been associated with increased cardiovascular disease (CVD), T2DM and chronic kidney disease (CKD) incidence. However, the association between obesity, MetS (including NAFLD) and diabetic microvascular complications is less evident.

METHODS

The present narrative review discusses the associations of obesity, MetS and NAFLD with diabetic kidney disease (DKD), diabetic retinopathy (DR) and diabetic peripheral neuropathy (DPN) as well as cardiac autonomic neuropathy (CAN). The available data on the effects of lifestyle measures and bariatric surgery on these diabetic complications are also briefly discussed.

RESULTS

Overall, both obesity and MetS have been related to DKD, DR and DPN, although conflicting results exist. Links between NAFLD and diabetic microvascular complications have also been reported but data are still limited. Lifestyle intervention and bariatric surgery may prevent the development and/or progression of these microvascular complications but more evidence is needed.

CONCLUSION

Clinicians should be aware of the frequent co-existence of MetS and/or NAFLD in T2DM patients to prevent or treat these metabolic disorders, thus potentially minimizing the risk for both CVD and diabetic microvascular complications.

Molecular mechanisms of splenectomy-induced hepatocyte proliferation

Functional and anatomical connection between the liver and the spleen is most clearly manifested in various pathological conditions of the liver (cirrhosis, hepatitis). The mechanisms of the interaction between the two organs are still poorly understood, as there have been practically no studies on the influence exerted by the spleen on the normal liver. Mature male Sprague-Dawley rats of 250-260 g body weight, 3 months old, were splenectomized. The highest numbers of Ki67+ hepatocytes in the liver of splenectomized rats were observed at 24 h after the surgery, simultaneously with the highest index of Ki67-positive hepatocytes. After surgical removal of the spleen, expression of certain genes in the liver tissues increased. A number of genes were upregulated in the liver at a single time point of 24 h, including Ccne1, Egf, Tnfa, Il6, Hgf, Met, Tgfb1r2 and Nos2. The expression of Ccnd1, Tgfb1, Tgfb1r1 and Il10 in the liver was upregulated over the course of 3 days after splenectomy. Monitoring of the liver macrophage populations in splenectomized animals revealed a statistically significant increase in the proportion of CD68-positive cells in the liver (as compared with sham-operated controls) detectable at 24 h and 48 h after the surgery. The difference in the liver content of CD68-positive cells between splenectomized and sham-operated animals evened out by day 3 after the surgery. No alterations in the liver content of CD163-positive cells were observed in the experiments. A decrease in the proportion of CD206-positive liver macrophages was observed at 48 h after splenectomy. The splenectomy-induced hepatocyte proliferation is described by us for the first time. Mechanistically, the effect is apparently induced by the removal of spleen as a major source of Tgfb1 (hepatocyte growth inhibitor) and subsequently supported by activation of proliferation factor-encoding genes in the liver.

Redox Regulation of the Microcirculation

The microcirculation maintains tissue homeostasis through local regulation of blood flow and oxygen delivery. Perturbations in microvascular function are characteristic of several diseases and may be early indicators of pathological changes in the cardiovascular system and in parenchymal tissue function. These changes are often mediated by various reactive oxygen species and linked to disruptions in pathways such as vasodilation or angiogenesis. This overview compiles recent advances relating to redox regulation of the microcirculation by adopting both cellular and functional perspectives. Findings from a variety of vascular beds and models are integrated to describe common effects of different reactive species on microvascular function. Gaps in understanding and areas for further research are outlined. © 2020 American Physiological Society. Compr Physiol 10:229-260, 2020.

Obesity-related cognitive impairment: The role of endothelial dysfunction

Obesity is a global pandemic associated with macro- and microvascular endothelial dysfunction. Microvascular endothelial dysfunction has recently emerged as a significant risk factor for the development of cognitive impairment. In this review, we present evidence from clinical and preclinical studies supporting a role for obesity in cognitive impairment. Next, we discuss how obesity-related hyperinsulinemia/insulin resistance, systemic inflammation, and gut dysbiosis lead to cognitive impairment through induction of endothelial dysfunction and disruption of the blood brain barrier. Finally, we outline the potential clinical utility of dietary interventions, exercise, and bariatric surgery in circumventing the impacts of obesity on cognitive function.

Microvascular Endothelial Dysfunction in Human Obesity: Role of TNF-α

CONTEXT

Endothelium guarantees vascular homeostasis by the opposite action of substances by vasodilating/antithrombogenic and vasoconstricting/prothrombotic activities. Obesity is characterized by endothelial dysfunction associated with a condition of vascular low-grade inflammation.

EVIDENCE ACQUISITION

Analysis of available basic or clinical papers published in peer-reviewed international journals on microcirculation and obesity.

EVIDENCE SYNTHESIS

Vascular low-grade inflammation, which characterizes obesity, is secondary to abnormal production of proinflammatory cytokines, including TNF-α. TNF-α, generated either in small vessels or within the perivascular adipose tissue (PVAT) of patients with obesity, stimulates reactive oxygen species generation, mainly through NAD(P)H oxidase activation, which in turn reduces nitric oxide (NO) availability. These aspects are highlighted by the insulin resistance status and macronutrient intake that characterize the obesity condition. Oxidant excess has also been proposed as a mechanism whereby TNF-α interferes with the endothelin-1/NO system at the level of small vessels from patients with obesity.

CONCLUSIONS

In obesity, microvasculature from visceral fat is an important source of low-grade inflammation and oxidative stress that, together with the PVAT, directly contribute to vascular changes, favoring the development and acceleration of the vascular atherothrombotic process in this clinical condition.

Luteolin Prevents Cardiometabolic Alterations and Vascular Dysfunction in Mice With HFD-Induced Obesity

Purpose: Luteolin exerts beneficial effects against obesity-associated comorbidities, although its influence on vascular dysfunction remains undetermined. We examined the effects of luteolin on endothelial dysfunction in a mouse model of diet-induced obesity. Methods: Standard diet (SD) or high-fat diet (HFD)-fed mice were treated daily with luteolin intragastrically. After 8 weeks, body and epididymal fat weight, as well as blood cholesterol, glucose, and triglycerides were evaluated. Endothelium-dependent relaxations of resistance mesenteric vessels was assessed by a concentration-response curve to acetylcholine, repeated upon N^w-nitro-L-arginine methylester (L-NAME) or ascorbic acid infusion to investigate the influence of nitric oxide (NO) availability and reactive oxygen species (ROS) on endothelial function, respectively. Intravascular ROS production and TNF levels were measured by dihydroethidium dye and ELISA, respectively. Endothelial NO synthase (eNOS) and superoxide dismutase 1 (SOD1), as well as microRNA-214-3p expression were examined by Western blot and RT-PCR assays, respectively. Results: HFD animals displayed elevated body weight, epididymal fat weight and metabolic indexes. Endothelium-dependent relaxation was resistant to L-NAME and enhanced by ascorbic acid, which restored also the inhibitory effect of L-NAME, suggesting a ROS-dependent reduction of NO availability in HFD vessels. Moreover, media-lumen ratio, intravascular superoxide anion and TNF levels were increased, while vascular eNOS, SOD1, and microRNA-214-3p expression were decreased. In HFD mice, luteolin counteracted the increase in body and epididymal fat weight, and metabolic alterations. Luteolin restored vascular endothelial NO availability, normalized the media-lumen ratio, decreased ROS and TNF levels, and normalized eNOS, SOD1 and microRNA-214-3p expression. Conclusion: Luteolin prevents systemic metabolic alterations and vascular dysfunction associated with obesity, likely through antioxidant and anti-inflammatory mechanisms.

Targeted Therapy of Atherosclerosis by a Broad-Spectrum Reactive Oxygen Species Scavenging Nanoparticle with Intrinsic Anti-inflammatory Activity

Atherosclerosis is a leading cause of vascular diseases worldwide. Whereas antioxidative therapy has been considered promising for the treatment of atherosclerosis in view of a critical role of reactive oxygen species (ROS) in the pathogenesis of atherosclerosis, currently available antioxidants showed considerably limited clinical outcomes. Herein, we hypothesize that a broad-spectrum ROS-scavenging nanoparticle can serve as an effective therapy for atherosclerosis, taking advantage of its antioxidative stress activity and targeting effects. As a proof of concept, a broad-spectrum ROS-eliminating material was synthesized by covalently conjugating a superoxide dismutase mimetic agent Tempol and a hydrogen-peroxide-eliminating compound of phenylboronic acid pinacol ester onto a cyclic polysaccharide β-cyclodextrin (abbreviated as TPCD). TPCD could be easily processed into a nanoparticle (TPCD NP). The obtained nanotherapy TPCD NP could be efficiently and rapidly internalized by macrophages and vascular smooth muscle cells (VSMCs). TPCD NPs significantly attenuated ROS-induced inflammation and cell apoptosis in macrophages, by eliminating overproduced intracellular ROS. Also, TPCD NPs effectively inhibited foam cell formation in macrophages and VSMCs by decreasing internalization of oxidized low-density lipoprotein. After intravenous (i.v.) administration, TPCD NPs accumulated in atherosclerotic lesions of apolipoprotein E-deficient (ApoE^-/-) mice by passive targeting through the dysfunctional endothelium and translocation via inflammatory cells. TPCD NPs significantly inhibited the development of atherosclerosis in ApoE^-/- mice after i.v. delivery. More importantly, therapy with TPCD NPs afforded stabilized plaques with less cholesterol crystals, a smaller necrotic core, thicker fibrous cap, and lower macrophages and matrix metalloproteinase-9, compared with those treated with control drugs previously developed for antiatherosclerosis. The therapeutic benefits of TPCD NPs mainly resulted from reduced systemic and local oxidative stress and inflammation as well as decreased inflammatory cell infiltration in atherosclerotic plaques. Preliminary in vivo tests implied that TPCD NPs were safe after long-term treatment via i.v. injection. Consequently, TPCD NPs can be developed as a potential antiatherosclerotic nanotherapy.

Obesity impairs leukocyte-endothelium cell interactions and oxidative stress in humans

BACKGROUND

To evaluate the relationship between leukocyte-endothelial cell interactions and oxidative stress parameters in non-diabetic patients with different grades of obesity.

MATERIAL AND METHODS

For this cross-sectional study, 225 subjects were recruited from January 1, 2014 to December 31, 2016 and divided into groups according to BMI (<30 kg/m² , 30-40 kg/m² and >40 kg/m²). We determined clinical parameters, systemic inflammatory markers, soluble cellular adhesion molecules, leukocyte-endothelium cell interactions-rolling flux, velocity and adhesion-, oxidative stress parameters-total ROS, total superoxide, glutathione-and mitochondrial membrane potential in leukocytes.

RESULTS

We verified that HOMA-IR and hsCRP increased progressively as obesity developed, whereas A1c, IL6 and TNFα were augmented in the BMI > 40 kg/m² group. The cellular adhesion molecule sP-selectin was increased in patients with obesity, while sICAM, total ROS, total superoxide and mitochondrial membrane potential were selectively higher in the BMI > 40 kg/m² group. Obesity induced a progressive decrease in rolling velocity and an enhancement of rolling flux and leukocyte adhesion.

CONCLUSION

Our findings reveal that endothelial dysfunction markers are altered in human obesity and are associated with proinflammatory cytokines and increased oxidative stress parameters.

Age- and Sex-Specific Reference Values for Media/Lumen Ratio in Small Arteries and Relationship With Risk Factors

Small-artery remodeling is an early feature of target organ damage in hypertension and retains a negative prognostic value. The aim of the study is to establish age- and sex-specific reference values for media/lumen in small arteries obtained in humans by biopsy. Data from 91 healthy individuals and 200 individuals with cardiovascular risk factors in primary prevention from 4 Italian centers were pooled. Sex-specific equations for media/lumen in the healthy subpopulation, with age as dependent variable, were calculated. These equations were used to calculate predicted media/lumen values in individuals with risk factors and Z scores. The association between classical risk factors and Z scores was then explored by multiple regression analysis. A second-degree polynomial equation model was chosen to obtain sex-specific equations for media/lumen, with age as dependent variable. In the population with risk factors (111 men, age 50.5±14.0 years, hypertension 80.5%), media/lumen Z scores were independently associated with body mass index (standardized β=0.293, P=0.0001), total cholesterol (β=0.191, P=0.031), current smoking (β=0.238, P=0.0005), fasting blood glucose (β=0.204, P=0.003), systolic blood pressure (β=0.233, P=0.023), and female sex (β=0.799, P=0.038). A significant interaction between female sex and total cholesterol was found (β=-0.979, P=0.014). Results were substantially similar in the hypertensive subgroup. A method to calculate individual values of remodeling and growth index based on reference values was also presented. Age- and sex-specific percentiles of media/lumen in a healthy population were estimated. In a predominantly hypertensive population, media/lumen Z scores were associated with major cardiovascular risk factors, including body mass index, cholesterol, smoking, glucose, and systolic blood pressure. Significant sex differences were observed.

Serum adiponectin and TNFα concentrations are closely associated with epicardial adipose tissue fatty acid profiles in patients undergoing cardiovascular surgery

BACKGROUND

Epicardial adipose tissue (EAT) releases both adiponectin and TNFα, and these two adipokines play important roles in heart diseases such as coronary arterial disease. The aim of the present study was to clarify whether fatty acid (FA) profiles in EAT are linked to the serum concentration of these adipokines. The relationships between serum adipokine levels and FA profiles in patients undergoing cardiovascular surgery were analyzed.

METHODS

Patients (n = 21) undergoing cardiovascular surgery (11 males, 70.4 ± 9.0 years, BMI 26.0 ± 5.1 kg/m2) were included. EAT samples were taken. We measured clinical biochemical data and FA profiles in venous blood and EAT samples using gas chromatography. Serum adiponectin and TNFα concentrations were also measured.

RESULTS

The adiponectin and TNFα levels were not correlated with any fatty acid concentration in serum lipids. In contrast, there was a positive correlation between the serum adiponectin level and epicardial level of nervonic acid (C24:1ω9, r = 0.525, P = 0.025). In multiple regression analysis, adiponectin showed a positive association with the epicardial C24:1ω9 concentration after controlling for age and BMI, or TG, non-HDL-C, and BNP. The serum TNFα concentration was negatively correlated with the epicardial C18:3ω3, C12:0 and C18:0 content. In multiple regression analysis, the serum TNFα concentration showed a positive association with the epicardial C18:3ω3 level (β = - 0.575, P = 0.015).

CONCLUSIONS

These results suggest that there is a close relationship between epicardial FA profiles and serum levels of adiponectin and TNFα. Dietary therapy to target FA profiles may be helpful to modulate inflammation.

Combined exercise reduces arterial stiffness, blood pressure, and blood markers for cardiovascular risk in postmenopausal women with hypertension

OBJECTIVE

Postmenopausal women exhibit elevated brachial-ankle pulse wave velocity (baPWV), an indicator of arterial stiffness, which is associated with an increased risk of cardiovascular events and mortality. The purpose of this study is to examine the impact of combined resistance and aerobic exercise training on baPWV, blood pressure (BP), and cardiovascular fitness in postmenopausal women with stage 1 hypertension.

METHODS

Twenty postmenopausal women (age, 75 ± 2 y; systolic BP, 152 ± 2 mm Hg, diastolic BP, 95 ± 3 mm Hg) were randomly assigned to a "no-exercise" (CON, n = 10) or combined exercise (EX, n = 10) group. The EX group performed resistance and aerobic exercise for 12 weeks, 3 times per week. Exercise intensity was increased gradually, from 40% to 70% of heart rate reserve, every 4 weeks. BaPWV, BP, blood nitrite/nitrate, endothelin-1 (ET-1), cardiovascular fitness, and body composition were measured before and after the 12-week intervention.

RESULTS

BP, baPWV (-1.2 ± 0.4 m/s), ET-1 (-2.7 ± 0.3 μmol/mL), nitrite/nitrate (+4.5 ± 0.5 μM), functional capacity, and body composition were significantly improved (P < 0.05) in the EX group after 12 weeks of training, but no changes were observed in the CON group.

CONCLUSIONS

These findings indicate that 12 weeks of combined exercise training improves arterial stiffness, BP, ET-1, blood nitrite/nitrate, functional capacity, and body composition in postmenopausal women with stage 1 hypertension. Thus, this study provides evidence that combined exercise training is a useful therapeutic method to improve cardiovascular health which can reduce cardiovascular disease risk in postmenopausal women with hypertension.

Comparisons between perivascular adipose tissue and the endothelium in their modulation of vascular tone

The endothelium is an established modulator of vascular tone; however, the recent discovery of the anti-contractile nature of perivascular adipose tissue (PVAT) suggests that the fat, which surrounds many blood vessels, can also modulate vascular tone. Both the endothelium and PVAT secrete vasoactive substances, which regulate vascular function. Many of these factors are common to both the endothelium and PVAT; therefore, this review will highlight the potential shared mechanisms in the modulation of vascular tone. Endothelial dysfunction is a hallmark of many vascular diseases, including hypertension and obesity. Moreover, PVAT dysfunction is now being reported in several cardio-metabolic disorders. Thus, this review will also discuss the mechanistic insights into endothelial and PVAT dysfunction in order to evaluate whether PVAT modulation of vascular contractility is similar to that of the endothelium in health and disease.

LINKED ARTICLES

This article is part of a themed section on Molecular Mechanisms Regulating Perivascular Adipose Tissue - Potential Pharmacological Targets? To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.20/issuetoc.

Microvascular NADPH oxidase in health and disease

The systemic and cerebral microcirculation contribute critically to regulation of local and global blood flow and perfusion pressure. Microvascular dysfunction, commonly seen in numerous cardiovascular pathologies, is associated with alterations in the oxidative environment including potentiated production of reactive oxygen species (ROS) and subsequent activation of redox signaling pathways. NADPH oxidases (Noxs) are a primary source of ROS in the vascular system and play a central role in cardiovascular health and disease. In this review, we focus on the roles of Noxs in ROS generation in resistance arterioles and capillaries, and summarize their contributions to microvascular physiology and pathophysiology in both systemic and cerebral microcirculation. In light of the accumulating evidence that Noxs are pivotal players in vascular dysfunction of resistance arterioles, selectively targeting Nox isozymes could emerge as a novel and effective therapeutic strategy for preventing and treating microvascular diseases.

Obesity-Induced Changes in Adipose Tissue Microenvironment and Their Impact on Cardiovascular Disease

Obesity is causally linked with the development of cardiovascular disorders. Accumulating evidence indicates that cardiovascular disease is the collateral damage of obesity-driven adipose tissue dysfunction that promotes a chronic inflammatory state within the organism. Adipose tissues secrete bioactive substances, referred to as adipokines, which largely function as modulators of inflammation. The microenvironment of adipose tissue will affect the adipokine secretome, having actions on remote tissues. Obesity typically leads to the upregulation of proinflammatory adipokines and the downregulation of anti-inflammatory adipokines, thereby contributing to the pathogenesis of cardiovascular diseases. In this review, we focus on the microenvironment of adipose tissue and how it influences cardiovascular disorders, including atherosclerosis and ischemic heart diseases, through the systemic actions of adipokines.

Abnormal Remodeling of Subcutaneous Small Arteries Is Associated With Early Diastolic Impairment in Metabolic Syndrome

Background

Small artery pathophysiology is frequently invoked as a cause of obesity‐related diastolic heart failure. However, evidence to support this hypothesis is scant, particularly in humans.

Methods and Results

To address this, we studied human small artery structure and function in obesity and looked for correlations between vascular parameters and diastolic function. Seventeen obese patients with metabolic syndrome and 5 control participants underwent echocardiography and subcutaneous gluteal fat biopsy. Small arteries were isolated from the biopsy and pressure myography was used to study endothelial function and wall structure. In comparison with the control group, small arteries from obese participants exhibited significant endothelial dysfunction, assessed as the vasodilatory response to acetylcholine and also pathological growth of the wall. For the obese participants, multiple regression analysis revealed an association between left atrial volume and both the small artery wall thickness (β=0.718, P=0.02) and wall‐to‐lumen ratio (β=0.605, P=0.02). Furthermore, the E:E′ ratio was associated with wall‐to‐lumen ratio (β=0.596, P=0.02) and inversely associated with interleukin‐6 (β=−0.868, P=0.03). By contrast, endothelial function did not correlate with any of the echocardiographic parameters studied.

Conclusions

Although the small arteries studied were not cardiac in origin, our results support a role for small artery remodeling in the development of diastolic dysfunction in humans. Further direct examination of the structure and function of the myocardial resistance vasculature is now warranted, to elucidate the temporal association between metabolic risk factors, small artery injury, and diastolic impairment.

Endothelial dysfunction and vascular disease - a 30th anniversary update

The endothelium can evoke relaxations of the underlying vascular smooth muscle, by releasing vasodilator substances. The best-characterized endothelium-derived relaxing factor (EDRF) is nitric oxide (NO) which activates soluble guanylyl cyclase in the vascular smooth muscle cells, with the production of cyclic guanosine monophosphate (cGMP) initiating relaxation. The endothelial cells also evoke hyperpolarization of the cell membrane of vascular smooth muscle (endothelium-dependent hyperpolarizations, EDH-mediated responses). As regards the latter, hydrogen peroxide (H₂ O₂ ) now appears to play a dominant role. Endothelium-dependent relaxations involve both pertussis toxin-sensitive G_i (e.g. responses to α₂ -adrenergic agonists, serotonin, and thrombin) and pertussis toxin-insensitive G_q (e.g. adenosine diphosphate and bradykinin) coupling proteins. New stimulators (e.g. insulin, adiponectin) of the release of EDRFs have emerged. In recent years, evidence has also accumulated, confirming that the release of NO by the endothelial cell can chronically be upregulated (e.g. by oestrogens, exercise and dietary factors) and downregulated (e.g. oxidative stress, smoking, pollution and oxidized low-density lipoproteins) and that it is reduced with ageing and in the course of vascular disease (e.g. diabetes and hypertension). Arteries covered with regenerated endothelium (e.g. following angioplasty) selectively lose the pertussis toxin-sensitive pathway for NO release which favours vasospasm, thrombosis, penetration of macrophages, cellular growth and the inflammatory reaction leading to atherosclerosis. In addition to the release of NO (and EDH, in particular those due to H₂ O₂ ), endothelial cells also can evoke contraction of the underlying vascular smooth muscle cells by releasing endothelium-derived contracting factors. Recent evidence confirms that most endothelium-dependent acute increases in contractile force are due to the formation of vasoconstrictor prostanoids (endoperoxides and prostacyclin) which activate TP receptors of the vascular smooth muscle cells and that prostacyclin plays a key role in such responses. Endothelium-dependent contractions are exacerbated when the production of nitric oxide is impaired (e.g. by oxidative stress, ageing, spontaneous hypertension and diabetes). They contribute to the blunting of endothelium-dependent vasodilatations in aged subjects and essential hypertensive and diabetic patients. In addition, recent data confirm that the release of endothelin-1 can contribute to endothelial dysfunction and that the peptide appears to be an important contributor to vascular dysfunction. Finally, it has become clear that nitric oxide itself, under certain conditions (e.g. hypoxia), can cause biased activation of soluble guanylyl cyclase leading to the production of cyclic inosine monophosphate (cIMP) rather than cGMP and hence causes contraction rather than relaxation of the underlying vascular smooth muscle.

Different Impact of Essential Hypertension on Structural and Functional Age-Related Vascular Changes

We evaluated whether vascular remodeling is present in physiological aging and whether hypertension accelerates the aging process for vascular function and structure. Small arteries from 42 essential hypertensive patients (HT) and 41 normotensive individuals (NT) were dissected after subcutaneous biopsy. Endothelium-dependent vasodilation (pressurized myograph) was assessed by acetylcholine, repeated under the nitric oxide synthase inhibitor N -nitro- l -arginine methylester or the antioxidant tempol. Structure was evaluated by media–lumen ratio (M/L). Intravascular oxidative generation and collagen deposition were assessed. Inhibition by N -nitro- l -arginine methylester on ACh was inversely related to age in both groups ( P <0.0001) and blunted in HT versus NT for each age range. In NT, tempol enhanced endothelial function in the oldest subgroup; in HT, the potentiating effect started earlier. HT showed an increased M/L ( P <0.001) versus control. In both groups, M/L was directly related to age ( P <0.0001). M/L was greater in HT, starting from 31 to 45 years range. A significant age–hypertension interaction occurred ( P =0.0009). In NT, intravascular superoxide emerged in the oldest subgroup, whereas it appeared earlier among HT. Among NT, aged group displayed an increment of collagen fibers versus young group. In HT, collagen deposition was already evident in youngest, with a further enhancement in the aged group. In small arteries, ageing shows a eutrophic vascular remodeling and a reduced nitric oxide availability. Oxidative stress and fibrosis emerge in advanced age. In HT, nitric oxide availability is early reduced, but the progression rate with age is similar. Structural alterations include wide collagen deposition and intravascular reactive oxygen species, and the progression rate with age is steeper.

Endothelial Dysfunction in Obesity

Chronic inflammatory state in obesity causes dysregulation of the endocrine and paracrine actions of adipocyte-derived factors, which disrupt vascular homeostasis and contribute to endothelial vasodilator dysfunction and subsequent hypertension. While normal healthy perivascular adipose tissue (PVAT) ensures the dilation of blood vessels, obesity-associated PVAT leads to a change in profile of the released adipo-cytokines, resulting in a decreased vasorelaxing effect. Adipose tissue inflammation, nitric oxide (NO)-bioavailability, insulin resistance and oxidized low-density lipoprotein (oxLDL) are main participating factors in endothelial dysfunction of obesity. In this chapter, disruption of inter-endothelial junctions between endothelial cells, significant increase in the production of reactive oxygen species (ROS), inflammation mediators, which are originated from inflamed endothelial cells, the balance between NO synthesis and ROS , insulin signaling and NO production, and decrease in L-arginine/endogenous asymmetric dimethyl-L-arginine (ADMA) ratio are discussed in connection with endothelial dysfunction in obesity.