Early experimental obesity is associated with coronary endothelial dysfunction and oxidative stress

Expanding landscape of coronary microvascular disease in co-morbid conditions: Metabolic disease and beyond

Coronary microvascular disease (CMD) and impaired coronary blood flow control are defects that occur early in the pathogenesis of heart failure in cardiometabolic conditions, prior to the onset of atherosclerosis. In fact, recent studies have shown that CMD is an independent predictor of cardiac morbidity and mortality in patients with obesity and metabolic disease. CMD is comprised of functional, structural, and mechanical impairments that synergize and ultimately reduce coronary blood flow in metabolic disease and in other co-morbid conditions, including transplant, autoimmune disorders, chemotherapy-induced cardiotoxicity, and remote injury-induced CMD. This review summarizes the contemporary state-of-the-field related to CMD in metabolic and these other co-morbid conditions based on mechanistic data derived mostly from preclinical small- and large-animal models in light of available clinical evidence and given the limitations of studying these mechanisms in humans. In addition, we also discuss gaps in current understanding, emerging areas of interest, and opportunities for future investigations in this field.

The Effect of Drug Use, Body Mass Index and Blood Pressure on Oxidative Stress Levels in Children and Adolescents with Attention Deficit and Hyperactivity Disorder

Objective

The aim of this study was to determine the correlation between clinical variables such as body mass index, blood pressure, drug use and oxidative stress level in children and adolescents with attention deficit and hyperactivity disorder (ADHD).

Methods

Total oxidant status (TOS), total antioxidant status (TAS), oxidative stress index (OSI), malondialdehyde (MDA) and superoxide dismutase (SOD) activity were measured in the serum of 51 patients (38 male, 13 female) diagnosed with ADHD according to DSM-5 diagnostic criteria and 32 control subjects (12 male, 20 female). The Kiddie Schedule for Affective Disorders and Schizophrenia Present and Lifetime Version was applied to all participants.

Results

The mean TOS, OSI, MDA values were determined to be significantly higher (p < 0.001) and the mean SOD value was lower in the ADHD group (p < 0.001). Multivariate regression analysis indicated significantly lower SOD and diastolic blood pressure values and significantly higher MDA in the ADHD group compared to the control group (p < 0.01). Low SOD (sensitivity 90.2%, specificity 78.0%) and high MDA (sensitivity 86.3%, specificity 81.2%) were determined to be predictive parameters for diagnosing ADHD. In univariate analysis, the mean TOS, OSI and SOD values were higher in ADHD patients under medication, while the mean TAS was higher in patients not using medication (p < 0.01). Only TOS was significant in multivariate logistic regression analysis (p < 0.01).

Conclusion

The results of this study demonstrate that impaired oxidative balance may play a role in the etiology of ADHD.

Mechanisms and clinical implications of endothelium-dependent vasomotor dysfunction in coronary microvasculature

Coronary microvascular disease (CMD), which affects the arterioles and capillary endothelium that regulate myocardial perfusion, is an increasingly recognized source of morbidity and mortality, particularly in the setting of metabolic syndrome. The coronary endothelium plays a pivotal role in maintaining homeostasis, though factors such as diabetes, hypertension, hyperlipidemia, and obesity can contribute to endothelial injury and consequently arteriolar vasomotor dysfunction. These disturbances in the coronary microvasculature clinically manifest as diminished coronary flow reserve, which is a known independent risk factor for cardiac death, even in the absence of macrovascular atherosclerotic disease. Therefore, a growing body of literature has examined the molecular mechanisms by which coronary microvascular injury occurs at the level of the endothelium and the consequences on arteriolar vasomotor responses. This review will begin with an overview of normal coronary microvascular physiology, modalities of measuring coronary microvascular function, and clinical implications of CMD. These introductory topics will be followed by a discussion of recent advances in the understanding of the mechanisms by which inflammation, oxidative stress, insulin resistance, hyperlipidemia, hypertension, shear stress, endothelial cell senescence, and tissue ischemia dysregulate coronary endothelial homeostasis and arteriolar vasomotor function.

ROS Modulating Effects of Lingonberry (Vaccinium vitis-idaea L.) Polyphenols on Obese Adipocyte Hypertrophy and Vascular Endothelial Dysfunction

Oxidative stress and dysregulated adipocytokine secretion accompanying hypertrophied adipose tissue induce chronic inflammation, which leads to vascular endothelial dysfunction. The present study investigated the ability of anthocyanin (ACN) and non-anthocyanin polyphenol (PP) fractions from lingonberry fruit to mitigate adipose tissue hypertrophy and endothelial dysfunction using 3T3-L1 adipocytes and human umbilical vein endothelial cells (HUVECs). This study showed that the PP fraction decreased intracellular ROS generation in hypertrophied adipocytes by enhancing antioxidant enzyme expression (SOD2) and inhibiting oxidant enzyme expression (NOX4, iNOS). Moreover, PP and ACN fractions reduced triglyceride content in adipocytes accompanied by downregulation of the expression of lipogenic genes such as aP2, FAS, and DAGT1. Treatment with both fractions modulated the mRNA expression and protein secretion of key adipokines in hypertrophied adipocytes. Expression and secretion of leptin and adiponectin were, respectively, down- and upregulated. Furthermore, PP and ACN fractions alleviated the inflammatory response in TNF-α-induced HUVECs by inhibiting the expression of pro-inflammatory genes (IL-6, IL-1β) and adhesion molecules (VCAM-1, ICAM-1, SELE). The obtained results suggest that consuming polyphenol-rich lingonberry fruit may help prevent and treat obesity and endothelial dysfunction due to their antioxidant and anti-inflammatory actions.

Oxidative Stress and Vascular Damage in the Context of Obesity: The Hidden Guest

The vascular system plays a central role in the transport of cells, oxygen and nutrients between different regions of the body, depending on the needs, as well as of metabolic waste products for their elimination. While the structure of different components of the vascular system varies, these structures, especially those of main arteries and arterioles, can be affected by the presence of different cardiovascular risk factors, including obesity. This vascular remodeling is mainly characterized by a thickening of the media layer as a consequence of changes in smooth muscle cells or excessive fibrosis accumulation. These vascular changes associated with obesity can trigger functional alterations, with endothelial dysfunction and vascular stiffness being especially common features of obese vessels. These changes can also lead to impaired tissue perfusion that may affect multiple tissues and organs. In this review, we focus on the role played by perivascular adipose tissue, the activation of the renin-angiotensin-aldosterone system and endoplasmic reticulum stress in the vascular dysfunction associated with obesity. In addition, the participation of oxidative stress in this vascular damage, which can be produced in the perivascular adipose tissue as well as in other components of the vascular wall, is updated.

Relationship of Obesity and Related Disorders with Ocular Parameters in Children and Adolescent

PURPOSE

To evaluate the effect of obesity and obesity-related high blood pressure (BP) on the retinal nerve fiber layer (RNFL) and macula in children and adolescents.

MATERIALS AND METHODS

Thirty-two obese patients followed up in the pediatrics endocrinology clinic between 2018 and 2019 were evaluated in the ophthalmology clinic. The results were compared with 25 healthy subjects, matched for age and sex. Anthropometric measurements, and systolic and diastolic BP were measured. The study consisted of three groups: Group 1, patients with obesity; Group 2, those with obesity and associated hypertension (obesity-related HT); and Group 3, healthy controls. A complete ophthalmologic examination was performed. Macular and RNFL thicknesses were determined using spectral domain optical coherence tomography (SD-OCT).

RESULTS

There were no statistically significant differences between the groups in terms of gender, age, and intraocular pressure (p > .05). The inferior RNFL thickness and central foveal thickness were statistically thinner in the obesity-related HT group (p < .001 and p = .040). The systolic and diastolic BP and fasting glucose values were significantly higher in the obesity-related HT group than the other groups (p < .001; p < .001; p = .026, respectively). In linear regression modeling in obese and obesity-related HT groups, a significant assocation was found between diastolic BP and temporal RNFL thickness (p = .027) as well as between the systolic BP and triglyceride values and the nasal RNFL thickness values (p = .016 and p = .025, respectively).

CONCLUSIONS

Inferior RNFL thickness and central foveal thickness were significantly thinner in patients with obesity-related HT. The effects of obesity-related HT on the retina should be evaluated using SD OCT, since no signs were found in a routine ocular examination.

Obesity-induced cognitive impairment in older adults: a microvascular perspective

Over two-thirds of individuals aged 65 and older are obese or overweight in the United States. Epidemiological data show an association between the degree of adiposity and cognitive dysfunction in the elderly. In this review, the pathophysiological roles of microvascular mechanisms, including impaired endothelial function and neurovascular coupling responses, microvascular rarefaction, and blood-brain barrier disruption in the genesis of cognitive impairment in geriatric obesity are considered. The potential contribution of adipose-derived factors and fundamental cellular and molecular mechanisms of senescence to exacerbated obesity-induced cerebromicrovascular impairment and cognitive decline in aging are discussed.

The role of oxidative stress in the development of obesity and obesity-related metabolic disorders

Obesity is a serious medical condition, defined as excessive accumulation of fat. Abdominal fat is recognized as the major risk for obesity related diseases such as: hypertension, dyslipidemia, type 2 diabetes mellitus, coronary heart disease, stroke, non-alcoholic fatty liver disease etc. Fat accumulation is also related to pro-oxidant and pro-inflammatory states. Recently published articles suggest that oxidative stress may be a link between obesity and related complications. Adiposity leads to increased oxidative stress via several multiple biochemical processes such as superoxide generation through the action of NADPH oxidase, glyceraldehyde auto-oxidation, oxidative phosphorylation, protein kinase C (PKC) activation, and polyol and hexosamine pathways. On the other hand, oxidative stress plays a causative role in the development of obesity, by stimulating the deposition of adipose tissue, including preadipocyte proliferation, adipocyte differentiation and growth. Exercise-induced weight loss can improve the redox state by modulating both oxidative stress and antioxidant promoters, which reduce endothelial dysfunction and inflammation.

When Two Pandemics Meet: Why Is Obesity Associated with Increased COVID-19 Mortality?

A growing body of evidence indicates that obesity is strongly and independently associated with adverse outcomes of COVID-19, including death. By combining emerging knowledge of the pathological processes involved in COVID-19 with insights into the mechanisms underlying the adverse health consequences of obesity, we present some hypotheses regarding the deleterious impact of obesity on the course of COVID-19. These hypotheses are testable and could guide therapeutic and preventive interventions. As obesity is now almost ubiquitous and no vaccine for COVID-19 is currently available, even a modest reduction in the impact of obesity on mortality and morbidity from this viral infection could have profound consequences for public health.

Air pollution inhalation during acute exercise is dependent of the body mass index and ventilation of young men

Obesity and physical inactivity threaten human health, and both could be solved with exercise. However, a higher amount of pollutants is inhaled during exercise. Exposure to air pollution increases the incidence and progression of diseases. Therefore, the aim of the study was to investigate the rate of pollution inhalation of lean, overweight, and obese individuals in a low and high-intensity hypothetical exercise session. Healthy sedentary men (n = 135) classified as lean, overweight, or obese were enrolled in our study. All participants performed a cardiopulmonary exercise testing (CPX) to collect ventilation rate (VE) data, which was used to predict total ventilation and pollutant inhalation of a 5-km running session. Air pollutant concentration of São Paulo City, Brazil was evaluated and the toxicological risk was estimated based on the potential intake dose. The concentrations of PM_2.5 were 29.57 μg/m³ and 51.71 μg/m³, PM₁₀ were 45.85 μg/m³ and 74 μg/m³, NO₂ were 63.71 μg/m³ and 66.65 μg/m³, and O₃ were 69 μg/m³ and 37 μg/m³, respectively in the summer and winter. In the hypothetical exercise session, total VE and time in both the first and second threshold were increased in the obese group (p < 0.001) (p < 0.001). The inhalation of PM_2.5, PM₁₀, NO₂, and O₃, during the hypothetical session, was increased in obese individuals (p < 0.001). Obese individuals should be considered a susceptible population, once they are more exposed to air pollution during exercise.

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.

Dietary intake of bioactive ingredients impacts liver and adipose tissue transcriptomes in a porcine model of prepubertal early obesity

Global prevalence of obesity has increased to epidemic proportions over the past 40 years, with childhood obesity reaching alarming rates. In this study, we determined changes in liver and adipose tissue transcriptomes of a porcine model for prepubertal early obesity induced by a high-calorie diet and supplemented with bioactive ingredients. A total of 43 nine-weeks-old animals distributed in four pens were fed with four different dietary treatments for 10 weeks: a conventional diet; a western-type diet; and a western-type diet with Bifidobacterium breve and rice hydrolysate, either adding or not omega-3 fatty acids. Animals fed a western-type diet increased body weight and total fat content and exhibited elevated serum concentrations of cholesterol, whereas animals supplemented with bioactive ingredients showed lower body weight gain and tended to accumulate less fat. An RNA-seq experiment was performed with a total of 20 animals (five per group). Differential expression analyses revealed an increase in lipogenesis, cholesterogenesis and inflammatory processes in animals on the western-type diet while the supplementation with bioactive ingredients induced fatty acid oxidation and cholesterol catabolism, and decreased adipogenesis and inflammation. These results reveal molecular mechanisms underlying the beneficial effects of bioactive ingredient supplementation in an obese pig model.

Emblica officinalis (Amla) Ameliorates High-Fat Diet Induced Alteration of Cardiovascular Pathophysiology

BACKGROUND

Dietary high fat possibly causes oxidative stress. Also, it alters the pathophysiology of metabolically active myocardial tissues and vascular architecture. Emblica officinalis contains a potential antioxidant that counteracts oxidative stress and possibly maintains vascular integrity.

OBJECTIVES

To assess the effect of ethanolic extract of Emblica officinalis (EEO) on High Fat Diet (HFD) induced changes in vascular chemistry and histopathology of the cardiovascular system in male albino rats.

MATERIALS AND METHODS

Ethanolic extract of Emblica officinalis (EEO) was prepared and phytochemical analysis was done. Rats were divided into four groups, having six rats in each group as follows: group 1- Control (20% fat); group 2 (20% fat+ EEO 100 mg/kg/b w); group 3 (30% fat) and group 4 (30% fat + EEO 100 mg/kg/b w). Dietary and EEO supplementation was continued for 21 days. Gravimetric and oxidative stress markers like MDA, NO, antioxidants like Vitamin C and E, and molecular marker (NOS₃) were evaluated. Histopathological analysis was done on the myocardium and elastic artery along with measurement of coronary arterial wall thickness and lumen diameter. One way ANOVA was done for analysis of data.

RESULTS

High fat diet showed a significant increase in MDA, decrease of NO with unaltered NOS₃ protein in rats fed with high fat diet, which indicate possible alteration of vascular pathophysiology. Supplementation of EEO showed an ameliorating effect on high fat diet induced oxidative stress. These results were further corroborated with findings of a histopathological study on the myocardium, elastic artery and coronary arterial architecture.

CONCLUSION

Ethanolic extract of Emblica officinalis (EEO) indicates its cardioprotective efficacy against rats fed with high fat diet.

Ginsenoside Rb1 Prevents Dysfunction of Endothelial Cells by Suppressing Inflammatory Response and Apoptosis in the High-Fat Diet Plus Balloon Catheter-Injured Rabbit Model via the G Protein-Coupled Estrogen Receptor-Mediated Phosphatidylinositol 3-Kinases (PI3K)/Akt Pathway

BACKGROUND The initiation of atherosclerosis (AS) is attributed to the dysfunction of endothelial cells (ECs) via the inhibition of g protein-coupled estrogen receptor (GPER). In the current study, we assessed the potential of Ginsenoside Rb1 (Rb1) to attenuate the dysfunction of ECs via GPER-mediated PI3K/Akt pathway. MATERIAL AND METHODS AS was induced in rabbits and then the AS rabbits were treated with Rb1. Thereafter, the ECs were isolated from AS and healthy rabbits, and treated with Rb1. The effect of Rb1 on blood lipid levels in AS rabbits and on apoptosis, inflammatory response, and GPER/PI3K/Akt axis activity in ECs was detected. Furthermore, the activities of GPER and PI3K were modulated to verify the key role of the axis in the anti-AS effect of Rb1. RESULTS The levels of total cholesterol, low-density lipoprotein (LDL), and triglyceride in AS rabbits were suppressed by Rb1 while the high-density lipoprotein (HDL) level was increased. In in vitro assays, Rb1 administration inhibited apoptosis process and the production of pro-inflammation cytokines in AS ECs. The expression levels of GPER, p-PI3K, and p-Akt were upregulated by Rb1, associated with the increased level of Bcl-2 and reduced level of Bax. When the activity of GPER was inhibited by GP-15 in AS ECs, the treatment effect of Rb1 was blocked. However, the activation of PI3K could restore the protective effect of Rb1 after the inhibition of GPER. CONCLUSIONS The anti-AS potential of Rb1 was exerted by restoring the regular function of ECs via the activation of GPER-mediated PI3K/Akt signaling.

Immunological Regulation of Vascular Inflammation During Cancer Metastasis

Metastasis is the predominant cause of cancer-related mortality, despite being a highly inefficient process overall. The vasculature is the gatekeeper for tumor cell seeding within the secondary tissue microenvironment—the rate limiting step of the metastatic cascade. Therefore, factors that regulate vascular physiology dramatically influence cancer outcomes. There are a myriad of physiologic circumstances that not only influence the intrinsic capacity of tumor cells to cross the endothelial barrier, but also that regulate vascular inflammation and barrier integrity to enable extravasation into the metastatic niche. These processes are highly dependent on inflammatory cues largely initiated by the innate immune compartment, that are meant to help re-establish tissue homeostasis, but instead become hijacked by cancer cells. Here, we discuss the scientific advances in understanding the interactions between innate immune cells and the endothelium, describe their influence on cancer metastasis, and evaluate potential therapeutic interventions for the alleviation of metastatic disease. By triangulating the relationship between immune cells, endothelial cells, and tumor cells, we will gain greater insight into how to impede the metastatic process by focusing on its most vulnerable phases, thereby reducing metastatic spread and cancer-related mortality.

Increased coronary arteriolar contraction to serotonin in juvenile pigs with metabolic syndrome

Metabolic syndrome (MetS) is associated with alterations in coronary vascular smooth muscle and endothelial function. The current study examined the contractile response of the isolated coronary arterioles to serotonin in pigs with and without MetS and investigated the signaling pathways responsible for serotonin-induced vasomotor tone. The MetS pigs (8-weeks old) were fed with a hyper-caloric, fat/cholesterol diet and the control animals (lean) were fed with a regular diet for 12 weeks (n = 6/group). The coronary arterioles (90–180 μm in diameter) were dissected from the harvested pig myocardial tissues and the in vitro coronary arteriolar response to serotonin was measured in the presence of pharmacological inhibitors. The protein expressions of phospholipase A2 (PLA₂), TXA₂ synthase, and the thromboxane-prostanoid (TP) receptor in the pigs’ left ventricular tissue samples were measured using Western blotting. Serotonin (10⁻⁹–10⁻⁵ M) induced dose-dependent contractions of coronary-resistant arterioles in both non-MetS control (lean) and MetS pigs. This effect was more pronounced in the MetS vessels compared with those of non-MetS controls (lean, P < 0.05]. Serotonin-induced contraction of the MetS vessels was significantly inhibited in the presence of the selective PLA₂ inhibitor quinacrine (10⁻⁶ M), the COX inhibitor indomethacin (10⁻⁵ M), and the TP receptor antagonist SQ29548 (10⁻⁶ M), respectively (P < 0.05). MetS exhibited significant increases in tissue levels of TXA₂ synthase and TP receptors (P < 0.05 vs. lean), respectively. MetS is associated with increased contractile response of porcine coronary arterioles to serotonin, which is in part via upregulation/activation of PLA₂, COX, and subsequent TXA₂, suggesting that alteration of vasomotor function may occur at an early stage of MetS and juvenile obesity.

Alterations in genetic and protein content of swine adipose tissue-derived mesenchymal stem cells in the metabolic syndrome

INTRODUCTION

Mesenchymal stem cells (MSCs) possess endogenous reparative properties and may serve as an exogenous therapeutic intervention in patients with chronic kidney disease. Cardiovascular risk factors clustering in the metabolic syndrome (MetS) might adversely affect cellular properties. To test the hypothesis that Mets interferes with MSC characteristics, we performed comprehensive comparison of the mRNA, microRNA, and protein content of MSCs isolated from Lean and MetS pigs.

METHODS

Domestic pigs were fed a 16-week Lean or MetS diet (n = 4 each). Expression profiles of co-existing microRNAs, mRNAs, and proteins were obtained by high-throughput sequencing and liquid chromatography-mass spectrometry. TargetScan and ComiR were used to predict target genes of differentially expressed microRNAs, and DAVID 6.7 for functional annotation analysis to rank primary gene ontology categories for the microRNA target genes, mRNAs, and proteins.

RESULTS

Differential expression analysis revealed 12 microRNAs upregulated in MetS-MSCs compared to Lean-MSCs (fold change>1.4, p < .05), which target 7728 genes, whereas 33 mRNAs and 78 proteins were downregulated (fold change<0.7, p < .05). Integrated analysis showed that targets of those microRNAs upregulated in MetS-MSCs overlap with at least half of mRNAs and proteins dysregulated in those cells. Functional analysis of overlapping mRNAs and proteins suggest that they are primarily involved in mitochondria, inflammation and transcription. MetS-MSCs also exhibited increased nuclear translocation of nuclear factor kappa-B, associated with increased SA-β-Galactosidase and decreased cytochrome-c oxidase-IV activity.

CONCLUSION

MetS alters the transcriptome and proteome of swine adipose tissue-derived MSCs particularly genes involved in mitochondria, inflammation and transcription regulation. These alterations might limit the reparative function of endogenous MSC and their use as an exogenous regenerative therapy.

Combined effects of Diospyros lotus leaf and grape stalk extract in high-fat-diet-induced obesity in mice

The aim of this study was to investigate the combined effects of Diospyros lotus leaves extracts (DLE) and Muscat Bailey A grape stalk extracts (MGSE) in obesity induced by high-fat diet (HFD) in mice. The mice were fed with HFD and orally administered daily with DLE, MGSE, a mixture of DLE and MGSE, and Garcinia cambogia extract over a period of 16 weeks. The results revealed that daily administration of DLE and MGSE mixtures markedly prevented HFD-induced weight gain, plasma lipid profile, hepatic steatosis, hepatic fibrosis, diabetic symptoms, and the risk of developing cardiovascular diseases. Also, DLE and MGSE mixtures administration greatly prevented oxidative stress and liver toxicity. The combined effects of DLE and MGSE mixtures were higher than effects of the single extracts and of G. cambogia, a plant known for its anti-obesity effects. In summary, these findings demonstrated that DLE and MGSE mixtures, exhibit anti-obesity activity in HFD-fed mice.

The Falconoid Luteolin Mitigates the Myocardial Inflammatory Response Induced by High-Carbohydrate/High-Fat Diet in Wistar Rats

Luteolin is a major component of many medicinal plants and traditional medicines. The current study aims at testing its protective effect against high-carbohydrate/high-fat (HCHF) diet-induced cardiac dysfunction in rats. Male Wistar rats were divided into six groups as follows: control group that received standard rat chow, group received HCHF diet (~ 30% carbohydrate and 42% fat) daily for 16 weeks, and four groups received HCHF diet concurrently with luteolin (10, 25, 50 or 100 mg/kg; 10% w/v suspension in 0.9% NaCl) daily from the first week by oral gavage. Body weight was measured weekly. At the end of the study, histopathological examinations of stained heart sections were carried out. Lipid profile, oxidative stress, and cardiac function biomarkers were measured. Furthermore, neurohumoral mediators and inflammatory cytokines (TNF-α, IL-18) were assigned. Results showed a significant improvement in cardiac function, tissue integrity, and a decrease in the compensatory neurohumoral mediators by luteolin 50 and 100 mg/kg. In addition, a significant (P < 0.05) decrease in collagen deposition, fibrosis percentage, lipid peroxidation, and inflammatory cells (macrophages and lymphocytes) infiltration was observed. Tested doses of luteolin decreased lipid peroxidation and elevated the endogenous antioxidant biomarkers (reduced glutathione and superoxide dismutase) significantly (P < 0.05). Finally, luteolin decreased TNF-α and IL-18 (P < 0.001) in a dose-dependent manner. It can be concluded that luteolin has a cardioprotective effect against HCHF diet-induced myocardial inflammation through antioxidant anti-inflammatory mechanisms.

A Comparative Study of Serum Biochemistry, Metabolome and Microbiome Parameters of Clinically Healthy, Normal Weight, Overweight, and Obese Companion Dogs

The aim of this study was to compare fecal microbiome, plasma, fecal and urine metabolomes, and serum biochemistry of adult companion dogs according to body condition scores. Blood, serum/plasma, urine, and fecal samples were collected from 66 clinically healthy, adult companion dogs of either normal weight (NW), overweight (OW), or obese dogs (OB). analyses included fecal microbiome analyses via 16S ribosomal RNA gene amplicon; sequencing, nontargeted plasma, fecal, and urine metabolomics using liquid chromatography/gas chromatography-mass; spectrometry, and serum biochemistry for each dog. Few significant differences in serum biochemistry and fecal microbiome Operational Taxonomic Unit (OTU) were found between weight groups and there was high OTU variation between individual dogs. NW dogs had higher relative abundance of the genus Eubacterium (log-fold change 4.3, adjusted P value = .003) and lower relative abundance of the family Bifidobacteriaceae (log-fold change -3.6, adjusted P value = .02) compared to OB dogs. The microbiome of NW dogs had higher OTU richness compared with OB dogs. Metabolome analysis showed 185 plasma, 37 fecal, and 45 urine metabolites that significantly differed between NW and OW or OB dogs. There were notable significant differences in relative abundance of several plasma phospholipid moieties and fecal volatile fatty acids between weight phenotypes. The combinations of host and gut microbiota and metabolic shifts suggest a pattern that could help detection of early metabolic changes in overweight dogs before the development of obesity related disease. The results of this study support the need for continued investigation into sensitive measures of metabolic aberrancies in overweight dogs.

Short-term weight loss reverses obesity-induced microvascular endothelial dysfunction

Obesity is one of the major risk factors for cardiovascular diseases and its prevalence is increasing in all age groups, with the biggest impact observed in middle-aged and older adults. A critical mechanism by which obesity promotes vascular pathologies in these patients involves impairment of endothelial function. While endothelial dysfunction in large vessels promotes atherogenesis, obesity-induced microvascular endothelial dysfunction impairs organ perfusion and thereby is causally related to the pathogenesis of ischemic heart disease, chronic kidney disease, intermittent claudication, exercise intolerance, and exacerbates cognitive decline in aging. Reduction of weight via calorie-based diet and exercise in animal models of obesity results in significant improvement of endothelial function both in large vessels and in the microcirculation, primarily due to attenuation of oxidative stress and inflammation. Clinical data on the protective effects of weight loss on endothelial function is limited to studies of flow-mediated dilation assessed in brachial arteries. Currently, there is no guideline on testing the effects of different weight management strategies on microvascular endothelial function in obese patients. Here, we provide proof-of-concept that weight loss-induced improvement of microvascular endothelial function can be reliably assessed in the setting of a geriatric outpatient clinic using a fast, reproducible, non-invasive method: laser speckle contrast imaging-based measurement of endothelium-dependent microvascular responses during post-occlusive reactive hyperemia tests. Our study also provides initial evidence that short-term weight loss induced by consumption of a low-carbohydrate low-calorie diet can reverse microvascular endothelial dysfunction associated with obesity.

Adiposity and Serum Selenium in U.S. Adults

Requirements for selenium and other antioxidant nutrients are increased in pro-oxidant and pro-inflammatory conditions such as excess adiposity. Data concerning the association of excess general and central adiposity with circulating selenium concentrations, however, are limited. We examined the cross-sectional associations of body mass index (BMI), percent body fat (%BF), and waist circumference (WC) with serum selenium concentrations in 6440 men and 6849 women aged ≥20 years who participated in the U.S. Third National Health and Nutrition Examination Survey. In multivariable analyses, the average difference (95% confidence interval (CI)) in serum selenium comparing the highest with the lowest quartiles of BMI was -4.0 (-5.5, -1.6) ng/mL in both men and women. These inverse associations were evident after further adjustment for WC. For %BF, the average differences (95% CI) in serum selenium between the highest and the lowest quartiles of %BF were -1.7 (-4.2, 0.7) ng/mL in men and -4.5 (-7.0, -1.9) ng/mL in women. The inverse association in women persisted after adjusting for WC. For WC, the average differences (95% CI) in serum selenium between the highest and the lowest quartiles were -1.9 (-3.8, -0.1) ng/mL in men and -3.9 (-5.8, -2.0) ng/mL in women. After further adjustment for BMI, the inverse association became positive in men and null in women. Our findings suggest that general and central adiposity have different associations with serum selenium levels and that these associations may depend on gender.

Biochemical and Ultrastructural Cardiac Changes Induced by High-Fat Diet in Female and Male Prepubertal Rabbits

Early weight gain induced by high-fat diet has been identified as a predictor for cardiac disease, one of the most serious public health problems. Our goal is to study the influence of a HFD on biochemical, oxidant stress parameters, and the cardiac ultrastructure in both male and female prepubertal models. Experiments were carried on 24 prepubertal New Zealand white rabbits, randomly assigned to male and female control (MC and FC, resp.) or HFD (MHFD and FHFD, resp.) groups (n = 6) for 3 months. Body and heart weights and some biochemical and oxidative stress parameters such as lipids, calcium, CKMB, MDA, uric acid, ascorbic acid, and AOA are evaluated in plasma and the left ventricle. Under HFD effect, plasma parameters, such as lipids (TL, PL, and LDL-C), MDA, and CK-MB, increase more significantly in male than in female groups, when AA decreases. Some cardiac parameters such as TG and UA increase, when AA and AOA decrease; these variations are more significant in FHFD. In both male and female rabbits, HFD caused changes in heart ultrastructure, junctional complexes, mitochondria size and form, and so on. Early HFD feeding induced overweight, oxidative stress, and metabolic alterations in plasma and the heart of prepubertal rabbits, whereas lipotoxicity has especially a negative impact on male plasma but affects more the female heart ultrastructure.

Impact of Obesity and Ozone on the Association Between Particulate Air Pollution and Cardiovascular Disease and Stroke Mortality Among US Adults

Background

Cardiovascular diseases (CVDs) and stroke are the highest and third highest causes of death, respectively, in the whole United States. It is well established that both long‐ and short‐term exposure to particulate air pollution (particulate matter with diameters <2.5 μm [PM_2.5]) increases the risks of both CVD and stroke mortality.

Methods and Results

We combined county‐level data for CVD and stroke mortality, and prevalence of hypertension and obesity, with spatial patterns of PM_2.5 and ozone in a cross‐sectional ecological study. We found significant positive associations between both CVD (β=15.4, P<0.001) and stroke (β=2.7, P<0.001) mortality with PM_2.5. Ozone had significant link with just CVD (β=1372.1, P<0.001). Once poverty, ethnicity, and education were taken into account, there were still significant positive associations between PM_2.5 and both CVD (β=1.2, P<0.001) and stroke (β=1.1, P<0.001) mortality. Moreover, the association between CVD and ozone remained after adjustment for these factors (β=21.8, P<0.001). PM_2.5 and ozone were independent risk factors. The impact of PM_2.5 on CVD and stroke mortality was strongly dependent on the prevalence of obesity. Hypertension partially mediated the associations of PM_2.5 and mortality from CVD and stroke.

Conclusions

There was a spatial association between PM_2.5 exposure and the leading causes of death and disability in United States. The effect of PM_2.5 was considerably greater in areas where obesity is more prevalent. Hypertension is a possible mediator of the association of PM_2.5 and both CVD and stroke.

Suppression of gut dysbiosis reverses Western diet-induced vascular dysfunction

Vascular dysfunction represents a critical preclinical step in the development of cardiovascular disease. We examined the role of the gut microbiota in the development of obesity-related vascular dysfunction. Male C57BL/6J mice were fed either a standard diet (SD) ( n = 12) or Western diet (WD) ( n = 24) for 5 mo, after which time WD mice were randomized to receive either unsupplemented drinking water or water containing a broad-spectrum antibiotic cocktail (WD + Abx) ( n = 12/group) for 2 mo. Seven months of WD caused gut dysbiosis, increased arterial stiffness (SD 412.0 ± 6.0 vs. WD 458.3 ± 9.0 cm/s, P < 0.05) and endothelial dysfunction (28% decrease in max dilation, P < 0.05), and reduced l-NAME-inhibited dilation. Vascular dysfunction was accompanied by significant increases in circulating LPS-binding protein (LBP) (SD 5.26 ± 0.23 vs. WD 11 ± 0.86 µg/ml, P < 0.05) and interleukin-6 (IL-6) (SD 3.27 ± 0.25 vs. WD 7.09 ± 1.07 pg/ml, P < 0.05); aortic expression of phosphorylated nuclear factor-κB (p-NF-κB) ( P < 0.05); and perivascular adipose expression of NADPH oxidase subunit p67phox ( P < 0.05). Impairments in vascular function correlated with reductions in Bifidobacterium spp. Antibiotic treatment successfully abrogated the gut microbiota and reversed WD-induced arterial stiffness and endothelial dysfunction. These improvements were accompanied by significant reductions in LBP, IL-6, p-NF-κB, and advanced glycation end products (AGEs), and were independent from changes in body weight and glucose tolerance. These results indicate that gut dysbiosis contributes to the development of WD-induced vascular dysfunction, and identify the gut microbiota as a novel therapeutic target for obesity-related vascular abnormalities.

Vascular dysfunction elicited by a cross talk between periaortic adipose tissue and the vascular wall is reversed by pioglitazone

AIM

Perivascular adipose tissue (PVAT) is in intimate contact with the vessel wall and extravascular PVAT-derived inflammatory mediators may adversely influence atherosclerotic plaque formation and stability through outside-to-inside signaling. We sought to investigate the role of PVAT on the atheroma development in an experimental animal model of metabolic syndrome (MS) associated with oxidative stress and low-grade inflammatory state. We also studied the effect of pioglitazone an insulin sensitizer, on the aortic wall and its surrounding PVAT, considering a bi-directional communication between both layers.

METHODS

Apolipoprotein E-deficient mice (ApoE^-/- ) were fed with standard diet (CD, control diet) or fructose overload (10% w/v) (FD, fructose diet) for 8 weeks and treated with or without pioglitazone the latest 4 weeks.

RESULTS

Biochemical variables show that glycemia and lipid peroxidation determined by thiobarbituric acid reactive species (TBARS) significantly increased in FD-fed ApoE^-/- mice. FD significantly increased aortic PVAT expression of oxidative stress associated genes: p22^phox , Nox1, Nox2, Nox4 and p47^phox , and proinflammatory genes: Visfatin, MCP-1, and MMP-9. Pioglitazone diminished PVAT-oxidative damage elicited by fructose treatment and markedly down-regulated proinflammatory markers. Even pioglitazone did not prevent the development of the aortic atheroma plaques stimulated by FD, significantly diminished VCAM-1 expression, MMP-9 expression and activity in aortic media wall and significantly reduced the accumulation of lipids and macrophages in atheroma plaques.

CONCLUSION

Our results support the fact that PVAT contributes to the development and progression of cardiovascular disease by underlying mechanisms elicited by "outside-in" signaling. Treatment with pioglitazone may offer a new effect on the whole vessel wall, promoting the stability of advanced atherosclerotic plaques.

Effects of thymol on amyloid-β-induced impairments in hippocampal synaptic plasticity in rats fed a high-fat diet

Obesity and a high-fat diet (HFD) are known to increase the incidence of Alzheimer's disease (AD). Oxidative stress, a major risk factor for AD, is increased with HFD consumption. Thymol (Thy) has antioxidant properties. Therefore, in the present study, we examined the protective and therapeutic effects of Thy on amyloid-β (Aβ)-induced impairments in the hippocampal synaptic plasticity of HFD-fed rats. In this study, 72 adult male Wistar rats were randomly assigned to 9 groups (n = 8 rats/group): Group 1 (control; standard diet); Group 2: Control + phosphate-buffered saline (PBS) + Oil (Thy vehicle); Group 3 (HFD + PBS); Group 4: (HFD + Aβ); Group 5: Control + PBS + Thy; Group 6: (HFD + Aβ + Oil); Group 7: Control + Aβ + Thy; Group 8: HFD + PBS + Thy; Group 9: (HFD + Aβ + Thy). After stereotaxic surgery, the field potentials were recorded after the implantation of the recording and stimulating electrodes in the dentate gyrus (DG) and perforant pathway, respectively. Following high-frequency stimulation, the long-term potentiation (LTP) of the population spike (PS) amplitude and the slope of the excitatory postsynaptic potentials (EPSPs) were measured in the DG. The HFD rats that received Aβ exhibited a significant decrease in their EPSP slope and PS amplitude as compared to the control group. In contrast, Thy administration in the HFD + Aβ rats reduced the decrease in the EPSP slope and PS amplitude. Thy decreased the Aβ-induced LTP impairments in HFD rats. The HFD significantly increased serum malondialdehyde levels and decreased total antioxidant capacity and total glutathione levels; whereas, Thy supplementation significantly reversed these parameters. Therefore, these results suggest that Thy, a natural antioxidant, can be therapeutic against high risk factors for AD, such as HFD.

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.

Selenium Status in Patients with Turner Syndrome: a Biochemical Assessment Related with Body Composition

Studies about selenium status in patients with Turner syndrome (TS) are non-existent in the literature. The aim of this study was to evaluate selenium status in patients with TS, while considering the different ages of the studied population and the relation with body composition. In total, 33 patients with TS were evaluated and grouped according to their developmental stages (children, adolescents, and adults). Selenium concentrations in their plasma, erythrocytes, urine, and nails were determined by using hydride generation atomic absorption spectrometry and erythrocyte glutathione peroxidase activity were measured by using Randox commercial kits. Additionally, height, weight, body fat percentage, waist circumference, and waist-height ratio were measured to characterize the patients. No differences in the selenium concentrations in the plasma, erythrocyte, urine, and nails or in the glutathione peroxidase activity were observed among the age groups (p > 0.05). The evaluated selenium levels were less than the established normal ones. The patients with larger waist circumference, body fat percentage, body mass index, and waist-height ratio showed lower glutathione peroxidase enzyme activity (p = 0.023). The present study shows that most patients with TS are deficient in selenium and that those with a greater accumulation of body fat have a lower GPx activity.

Epicardial fat thickness and oxidative stress parameters in patients with subclinical hypothyroidism

INTRODUCTION

Thyroid disorders are known to be a risk factor for cardiovascular diseases. Epicardial fat thickness (EFT) and oxidative stress are also believed to be major risk factors for cardiovascular events. The aim of this study was to evaluate the possible relationship between oxidative stress parameters and EFT in patients with subclinical hypothyroidism (SCH).

MATERIAL AND METHODS

A total of 60 individuals (30 patients with SCH and 30 healthy controls) were recruited for the study. The EFT and oxidative stress parameters of all participants were analyzed at baseline; the same were analyzed in SCH patients after achievement of a euthyroid state.

RESULTS

Compared to healthy subjects, SCH patients had significantly higher EFT and oxidative stress parameters (p < 0.05 for all). EFT and oxidative stress parameters both decreased after treatment, but only the decrease of EFT levels was statistically significant after thyroid hormone replacement (p < 0.05). Serum EFT levels were not significantly correlated with oxidative stress index (r = 0.141, p = 0.458).

CONCLUSIONS

Previous studies have demonstrated that visceral adipose tissue and oxidative stress are major risk factors for cardiovascular events; our study demonstrated that EFT, a visceral adipose tissue, and oxidative stress parameters were higher, and could be used as an indicator for cardiovascular diseases in patients with SCH.

Altered glucose and lipid homeostasis in liver and adipose tissue pre-dispose inducible NOS knockout mice to insulin resistance

On the basis of diet induced obesity and KO mice models, nitric oxide is implied to play an important role in the initiation of dyslipidemia induced insulin resistance. However, outcomes using iNOS KO mice have so far remained inconclusive. The present study aimed to assess IR in iNOS KO mice after 5 weeks of LFD feeding by monitoring body composition, energy homeostasis, insulin sensitivity/signaling, nitrite content and gene expressions changes in the tissues. We found that body weight and fat content in KO mice were significantly higher while the respiratory exchange ratio (RER), volume of carbon dioxide (VCO₂), and heat production were lower as compared to WT mice. Furthermore, altered systemic glucose tolerance, tissue insulin signaling, hepatic gluconeogenesis, augmented hepatic lipids, adiposity, as well as gene expression regulating lipid synthesis, catabolism and efflux were evident in iNOS KO mice. Significant reduction in eNOS and nNOS gene expression, hepatic and adipose tissue nitrite content, circulatory nitrite was also observed. Oxygen consumption rate of mitochondrial respiration has remained unaltered in KO mice as measured using extracellular flux analyzer. Our findings establish a link between the NO status with systemic and tissue specific IR in iNOS KO mice at 5 weeks.

Obesity and the Critical Care Pregnant Patient

The rise of obesity among gravid women has been tracked and documented in many first-world countries, but a dramatic rise has been noted over the last 15 years. Definitions of "normal-weight, overweight and obese" have been defined; however, new terms are used to describe more severe degrees of obesity. Obesity in any form or degree increases morbidities in mothers. The unique physiologic characteristics of the obese gravida set up unique challenges in her management, especially in an acute setting such as labor. The definitions, trends, and management decisions pertaining to the obese parturient will be described in this review.

Therapeutic applications of conditioned medium from adipose tissue

For the past number of decades, adipose tissue has attracted significant interest due to its complicated composition and versatile functions. Adipose tissue is no longer considered to be just an energy-storing fat pad, but is also a key ring player in interaction networks between various organs and tissues. A wide range of factors released by adipose tissue are responsible for regulation of adipose tissue and other distant target tissues and cells, such as kidneys, skeletal muscle, the cardiovascular system and the immune system, in an auto-/paracrine manner. A mixture of bioactive molecules makes up the conditioned medium of adipose tissue. The beneficial role played by these bioactive molecules in angiogenesis, wound healing, tissue regeneration and immunomodulation has been demonstrated by various studies. Study of this conditioned medium helps deepen our understanding of underlying mechanisms and broadens the potential for therapeutic applications. In this review, we have aimed to improve fundamental understanding of conditioned medium from adipose tissue and to summarize recent efforts to study its therapeutic applications.

Mitochondrial biogenesis is decreased in skeletal muscle of pig fetuses exposed to maternal high-energy diets

Mitochondria plays an important role in the regulation of energy homeostasis. Moreover, mitochondrial biogenesis accompanies skeletal myogenesis, and we previously reported that maternal high-energy diet repressed skeletal myogenesis in pig fetuses. Therefore, the aim of this study was to evaluate the effects of moderately increased maternal energy intake on skeletal muscle mitochondrial biogenesis and function of the pig fetuses. Primiparous purebred Large White sows were allocated to a normal energy intake group (NE) as recommended by the National Research Council (NRC) and a high energy intake group (HE, 110% of NRC recommendations). On day 90 of gestation, fetal umbilical vein blood and longissimus (LM) muscle were collected. Results showed that the weight gain of sows fed HE diet was higher than NE sows on day 90 of gestation (P<0.05). Maternal HE diet increased fetal umbilical vein serum triglyceride and insulin concentrations (P<0.05), and tended to increase the homeostasis model assessment index (P=0.08). Furthermore, HE fetuses exhibited increased malondialdehyde concentration (P<0.05), and decreased activities of antioxidative enzymes (P<0.05) and intracellular NAD+ level (P<0.05) in LM muscle. These alterations in metabolic traits of HE fetuses were accompanied by reduced mitochondrial DNA amount (P<0.05) and down-regulated messenger RNA expression levels of genes responsible for mitochondrial biogenesis and function (P<0.05). Our results suggest that moderately increased energy supply during gestation decreases mitochondrial biogenesis, function and antioxidative capacity in skeletal muscle of pig fetuses.

Treatment of lean and diet-induced obesity (DIO) mice with a novel stable obestatin analogue alters plasma metabolite levels as detected by untargeted LC-MS metabolomics

INTRODUCTION

Obestatin is a controversial gastrointestinal peptide purported to have metabolic actions.

OBJECTIVES

This study investigated whether treatment with a stable obestatin analogue (PEG-OB(Cys¹⁰, Cys¹³)) changed plasma metabolite levels firstly in lean and subsequently in diet-induced obesity (DIO) C57BL6/J mice.

METHODS

Untargeted LC-HRMS metabolomics experiments were carried out in ESI + mode with plasma extracts from both groups of animals. Data were normalised, multivariate and univariate statistical analysis performed and metabolites of interest putatively identified.

RESULTS

In lean mice, 39 metabolites were significantly changed by obestatin treatment and the majority of these were increased, including various C16 and C18 moieties of phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine and monoacylglycerol, along with vitamin A, vitamin D3, tyrosine, acetylcarnitine and 2α-(hydroxymethyl)-5α-androstane-3β,17β-diol. Decreased concentrations of glycolithocholic acid, 3-dehydroteasterone and various phospholipids were observed. In DIO mice, 25 metabolites were significantly affected and strikingly, the magnitudes of changes here were generally much greater in DIO mice than in lean mice, and in contrast, the majority of metabolite changes were decreases. Four metabolites affected in both groups included glycolithocholic acid, and three different long-chain (C18) phospholipid molecules (phosphatidylethanolamine, platelet activating factor (PAF), and monoacylglycerol). Metabolites exclusively affected in DIO mice included various phosphatidylcholines, lysophosphatidylcholines and fatty acyls, as well as creatine and oxidised glutathione.

CONCLUSION

This investigation demonstrates that obestatin treatment affects phospholipid turnover and influences lipid homeostasis, whilst providing convincing evidence that obestatin may be acting to ameliorate diet-induced impairments in lipid metabolism, and it may influence steroid, bile acid, PAF and glutathione metabolism.

Elucidating the role of the host genome in shaping microbiome composition

A major goal of microbiome research is to identify the factors that determine bacterial composition within and upon a host. Environmental factors are thought to play a large role, such as diet in determining gut microbiome composition and moisture in determining skin microbiome composition. The role of host genetics, however, has been a source of debate in the literature. Recently, we examined the association of host genetics with human gut microbiome composition in the Hutterites, a population that lives and eats communally. We identified heritable bacterial taxa and host genetic loci associated with their abundances. In this addendum, I put these results into a broader context along with other recent studies of microbiome heritability, and synthesize common themes that appear across organisms and tissues, such as the relatively small extent genetics plays compared to environment and the role of host genetic variation in immune response and barrier integrity.

Nanoformulated copper/zinc superoxide dismutase attenuates vascular cell activation and aortic inflammation in obesity

OBJECTIVE

Endothelial cell (EC) oxidative stress can lead to vascular dysfunction which is an underlying event in the development of cardiovascular disease (CVD). The lack of a potent and bioavailable anti-oxidant enzyme is a major challenge in studies on antioxidant therapy. The objective of this study is to determine whether copper/zinc superoxide dismutase (CuZnSOD or SOD1) after nanoformulation (nanoSOD) can effectively reduce EC oxidative stress and/or vascular inflammation in obesity.

METHODS

Human aortic endothelial cells (HAECs) were treated with native- or nanoSOD for 6 h followed by treatment with linoleic acid (LA), a free fatty acid, for 6-24 h. To determine the in vivo relevance, the effectiveness of nanoSOD in reducing vascular cell activation was studied in a mouse model of diet-induced obesity.

RESULTS

We noted that nanoSOD was more effectively taken up by ECs than native SOD. Western blot analysis further confirmed that the intracellular accumulation of SOD1 protein was greatly increased upon nanoSOD treatment. Importantly, nanoSOD pretreatment led to a significant decrease in LA-induced oxidative stress in ECs which was associated with a marked increase in SOD enzyme activity in ECs. In vivo studies showed a significant decrease in markers of EC/vascular cell activation and/or inflammation in visceral adipose tissue (VAT), thoracic aorta, and heart collected from nanoSOD-treated mice compared to obese control mice. Interestingly, the expression of metallothionein 2, an antioxidant gene was significantly increased in nanoSOD-treated mice.

CONCLUSION

Our data show that nanoSOD is very effective in delivering active SOD to ECs and in reducing EC oxidative stress. Our data also demonstrate that nanoSOD will be a useful tool to reduce vascular cell activation in VAT and aorta in obesity which, in turn, can protect against obesity-associated CVD, in particular, hypertension.

Genome-Wide Association Studies of the Human Gut Microbiota

The bacterial composition of the human fecal microbiome is influenced by many lifestyle factors, notably diet. It is less clear, however, what role host genetics plays in dictating the composition of bacteria living in the gut. In this study, we examined the association of ~200K host genotypes with the relative abundance of fecal bacterial taxa in a founder population, the Hutterites, during two seasons (n = 91 summer, n = 93 winter, n = 57 individuals collected in both). These individuals live and eat communally, minimizing variation due to environmental exposures, including diet, which could potentially mask small genetic effects. Using a GWAS approach that takes into account the relatedness between subjects, we identified at least 8 bacterial taxa whose abundances were associated with single nucleotide polymorphisms in the host genome in each season (at genome-wide FDR of 20%). For example, we identified an association between a taxon known to affect obesity (genus Akkermansia) and a variant near PLD1, a gene previously associated with body mass index. Moreover, we replicate a previously reported association from a quantitative trait locus (QTL) mapping study of fecal microbiome abundance in mice (genus Lactococcus, rs3747113, P = 3.13 x 10⁻⁷). Finally, based on the significance distribution of the associated microbiome QTLs in our study with respect to chromatin accessibility profiles, we identified tissues in which host genetic variation may be acting to influence bacterial abundance in the gut.

Göttingen minipig model of diet-induced atherosclerosis: influence of mild streptozotocin-induced diabetes on lesion severity and markers of inflammation evaluated in obese, obese and diabetic, and lean control animals

Background

From a pharmacological perspective, readily-available, well-characterized animal models of cardiovascular disease, including relevant in vivo markers of atherosclerosis are important for evaluation of novel drug candidates. Furthermore, considering the impact of diabetes mellitus on atherosclerosis in human patients, inclusion of this disease aspect in the characterization of a such model, is highly relevant. The objective of this study was to evaluate the effect of mild streptozotocin-induced diabetes on ex- and in vivo end-points in a diet-induced atherosclerotic minipig model.

Methods

Castrated male Göttingen minipigs were fed standard chow (CD), atherogenic diet alone (HFD) or with superimposed mild streptozotocin-induced diabetes (HFD-D). Circulating markers of inflammation (C-reactive protein (CRP), oxidized low-density lipoprotein (oxLDL), plasminogen activator inhibitor-1, lipid and glucose metabolism were evaluated together with coronary and aortic atherosclerosis after 22 or 43 diet-weeks. Group differences were evaluated by analysis of variance for parametric data and Kruskal–Wallis test for non-parametric data. For qualitative assessments, Fisher’s exact test was applied. For all analyses, p < 0.05 was considered statistically significant.

Results

Overall, HFD and HFD-D displayed increased CRP, oxLDL and lipid parameters compared to CD at both time points. HFD-D displayed impaired glucose metabolism as compared to HFD and CD. Advanced atherosclerotic lesions were observed in both coronary arteries and aorta of HFD and HFD-D, with more advanced plaque findings in the aorta but without differences in lesion severity or distribution between HFD and HFD-D. Statistically, triglyceride was positively (p = 0.0039), and high-density lipoprotein negatively (p = 0.0461) associated with aortic plaque area.

Conclusions

In this model, advanced coronary and aortic atherosclerosis was observed, with increased levels of inflammatory markers, clinically relevant to atherosclerosis. No effect of mild streptozotocin-induced diabetes was observed on plaque area, lesion severity or inflammatory markers.

Electronic supplementary material

The online version of this article (doi:10.1186/s12967-015-0670-2) contains supplementary material, which is available to authorized users.

α-Tocopherol Improves Microcirculatory Dysfunction on Fructose Fed Hamsters

Fructose, an everyday component of western diet associated to chronic hyperglycemia and enhanced free radical production, impairs endothelial function and supplementation with antioxidants might improve it. In this study we investigated if vitamin E could reverse the microvascular damage elicited by fructose. Male Syrian golden hamsters drank either 10% fructose solution (F) or filtered water (C), combined with three concentrations of vitamin E in their chows [zero, normal (VE) or 5X (5XVE)] during 60 days. Microvascular reactivity in response to topical application of acetylcholine (Ach; endothelium-dependent vasodilator) or sodium nitroprusside (SNP; endothelium-independent vasodilator) and macromolecular permeability increase induced by either 30 min ischemia followed by reperfusion (I/R) or topical application of histamine (5 μM) were assessed using the cheek pouch preparation. Compared to controls (drinking filtered water), fructose-drinking animals showed decreased vasodilatation to acetylcholine in all concentrations tested (-56.2% for 10^-9M, -53.9% for 10^-7M and -43.7% for 10^-5M). On the other hand, vitamin E supplementation resulted in increased responses for both water and fructose drinking groups (177.4% for F vs. F/5XVE and 241.6% for C vs. C/5XVE for 10^-5M Ach). Endothelial-independent vasodilatation explored by topical application of SNP was restored and even enhanced with the supplementation of 5X vitamin E in both groups (80.1% for F vs. F/5XVE; 144.2% for C vs. C/5XVE; 3.4% of difference for C/5XVE vs. F/5XVE on 10^-5M SNP). The number of leaky sites after I/R and histamine stimuli in vitamin E supplemented animals decreased (-25.1% and -15.3% for F vs. F/5XVE; and -21.7% and -16% of leaky sites comparing C vs. C/5XVE, respectively for I/R and histamine stimuli) pointing to tightening of the endothelial barrier for macromolecular permeability. Our results strongly suggest that vitamin E could improve the endothelial function and permeability barrier and also reverse impairments elicited by sugar overload.

Endothelin-1 contributes to endothelial dysfunction and enhanced vasoconstriction through augmented superoxide production in penile arteries from insulin-resistant obese rats: role of ET(A) and ET(B) receptors

BACKGROUND AND PURPOSE

We assessed whether endothelin-1 (ET-1) inhibits NO and contributes to endothelial dysfunction in penile arteries in a model of insulin resistance-associated erectile dysfunction (ED).

EXPERIMENTAL APPROACH

Vascular function was assessed in penile arteries, from obese (OZR) and lean (LZR) Zucker rats, mounted in microvascular myographs. Changes in basal and stimulated levels of superoxide (O2 (-) ) were detected by lucigenin-enhanced chemiluminescence and ET receptor expression was determined by immunohistochemistry.

KEY RESULTS

ET-1 stimulated acute O2 (-) production that was blunted by tempol and the NADPH oxidase inhibitor, apocynin, but markedly enhanced in obese animals. ET-1 inhibited the vasorelaxant effects of ACh and of the NO donor S-nitroso-N-acetyl-DL-penicillamine in arteries from both LZR and OZR. Selective ETA (BQ123) or ETB receptor (BQ788) antagonists reduced both basal and ET-1-stimulated superoxide generation and reversed ET-1-induced inhibition of NO-mediated relaxations in OZR, while only BQ-123 antagonized ET-1 actions in LZR. ET-1-induced vasoconstriction was markedly enhanced by NO synthase blockade and reduced by endothelium removal and apocynin. In endothelium-denuded penile arteries, apocynin blunted augmented ET-1-induced contractions in OZR. Both ETA and ETB receptors were expressed in smooth muscle and the endothelial layer and up-regulated in arteries from OZR.

CONCLUSIONS AND IMPLICATIONS

ET-1 stimulates ETA -mediated NADPH oxidase-dependent ROS generation, which inhibits endothelial NO bioavailability and contributes to ET-1-induced contraction in healthy penile arteries. Enhanced vascular expression of ETB receptors contributes to augmented ROS production, endothelial dysfunction and increased vasoconstriction in erectile tissue from insulin-resistant obese rats. Hence, antagonism of ETB receptors might improve the ED associated with insulin-resistant states.

COX-2 is involved in vascular oxidative stress and endothelial dysfunction of renal interlobar arteries from obese Zucker rats

Obesity is related to vascular dysfunction through inflammation and oxidative stress and it has been identified as a risk factor for chronic renal disease. In the present study, we assessed the specific relationships among reactive oxygen species (ROS), cyclooxygenase 2 (COX-2), and endothelial dysfunction in renal interlobar arteries from a genetic model of obesity/insulin resistance, the obese Zucker rats (OZR). Relaxations to acetylcholine (ACh) were significantly reduced in renal arteries from OZR compared to their counterpart, the lean Zucker rat (LZR), suggesting endothelial dysfunction. Blockade of COX with indomethacin and with the selective blocker of COX-2 restored the relaxations to ACh in obese rats. Selective blockade of the TXA2/PGH2 (TP) receptor enhanced ACh relaxations only in OZR, while inhibition of the prostacyclin (PGI2) receptor (IP) enhanced basal tone and inhibited ACh vasodilator responses only in LZR. Basal production of superoxide was increased in arteries of OZR and involved NADPH and xanthine oxidase activation and NOS uncoupling. Under conditions of NOS blockade, ACh induced vasoconstriction and increased ROS generation that were augmented in arteries from OZR and blunted by COX-2 inhibition and by the ROS scavenger tempol. Hydrogen peroxide (H2O2) evoked both endothelium- and vascular smooth muscle (VSM)-dependent contractions, as well as ROS generation that was reduced by COX-2 inhibition. In addition, COX-2 expression was enhanced in both VSM and endothelium of renal arteries from OZR. These results suggest that increased COX-2-dependent vasoconstriction contributes to renal endothelial dysfunction through enhanced (ROS) generation in obesity. COX-2 activity is in turn upregulated by ROS.

The Role of Obesity in Preeclampsia

The incidence of obesity is increasing at an alarming rate. There is compelling evidence that obesity increases the risk of preeclampsia about 3-fold, and in developed countries is the leading attributable risk for the disorder. In this presentation we explore this relationship and propose targets for future studies guided by the much more extensively studied relationship of obesity to cardiovascular disease. We further address the hypothesis that asymmetric dimethyl arginine (ADMA), an endogenous inhibitor of nitric oxide synthase, may be one convergence point for the mechanism by which obesity increases the risk of preeclampsia. We conclude with consideration of the clinical implications of this information.

Antioxidative diet supplementation reverses high-fat diet-induced increases of cardiovascular risk factors in mice

Obesity is a worldwide epidemic that is characterized not only by excessive fat deposition but also by systemic microinflammation, high oxidative stress, and increased cardiovascular risk factors. While diets enriched in natural antioxidants showed beneficial effects on oxidative stress, blood pressure, and serum lipid composition, diet supplementation with synthetic antioxidants showed contradictive results. Thus, we tested in C57Bl/6 mice whether a daily dosage of an antioxidative mixture consisting of vitamin C, vitamin E, L-arginine, eicosapentaenoic acid, and docosahexaenoic acid (corabion) would affect cardiovascular risk factors associated with obesity. Obese mice showed increased serum triglyceride and glucose levels and hypertension after eight weeks of being fed a high-fat diet (HFD). Importantly, corabion ameliorated all of these symptoms significantly. Oxidative stress and early signs of systemic microinflammation already developed after two weeks of high-fat diet and were significantly reduced by daily doses of corabion. Of note, the beneficial effects of corabion could not be observed when applying its single antioxidative components suggesting that a combination of various nutrients is required to counteract HFD-induced cardiovascular risk factors. Thus, daily consumption of corabion may be beneficial for the management of obesity-related cardiovascular complications.

Green tea changes serum and liver metabolomic profiles in mice with high-fat diet-induced obesity

SCOPE

Green tea (GT) consumption helps to prevent and control obesity by stimulating hepatic lipid metabolism. However, GT-induced changes in serum and liver metabolomes associated with the anti-obesity effects are not clearly understood. The aim of this study was to identify and validate metabolomic profiles in the livers and sera of GT-fed obese mice to elucidate the relationship between GT consumption and obesity prevention.

METHODS AND RESULTS

Serum and liver metabolites were analyzed in mice fed normal diet, high-fat diet (HFD), HFD with GT, and HFD with crude catechins, using LC-quadrupole TOF MS. The addition of 1% GT to HFD reduced adipose tissue and the levels of blood triglycerides, glucose, insulin, and leptin elevated in HFD-fed mice. We proposed an HFD-induced obesity pathway and validated it by investigating the key regulatory enzymes of mitochondrial β-oxidation: carnitine palmitoyltransferase-1 and -2, acyl-coenzyme A dehydrogenase, and acetyl-coenzyme A acyltransferase. The results showed that HFD-induced abnormal mitochondrial β-oxidation was moderated by the consumption of caffeine- and theanine-enriched GT.

CONCLUSION

Results of LC/MS-based metabolomic analysis of obese mice showed changes associated with abnormal lipid and energy metabolism, which were alleviated by GT intake, indicating the mechanism underlying the anti-obesity effects of GT.

Adipose tissue remodeling in a novel domestic porcine model of diet-induced obesity

OBJECTIVE

To establish and characterize a novel domestic porcine model of obesity.

METHODS

Fourteen domestic pigs were fed normal (lean, n=7) or high-fat/high-fructose diet (obese, n=7) for 16 weeks. Subcutaneous abdominal adipose tissue biopsies were obtained after 8, 12, and 16 weeks of diet, and pericardial adipose tissue after 16 weeks, for assessments of adipocyte size, fibrosis, and inflammation. Adipose tissue volume and cardiac function were studied with multidetector computed tomography, and oxygenation was studied with magnetic resonance imaging. Plasma lipids profile, insulin resistance, and markers of inflammation were evaluated.

RESULTS

Compared with lean pigs, obese pigs had elevated cholesterol and triglyceride levels, blood pressure, and insulin resistance. Both abdominal and pericardial fat volume increased in obese pigs after 16 weeks. In abdominal subcutaneous adipose tissue, adipocyte size and both tumor necrosis factor (TNF)-α expression progressively increased. Macrophage infiltration showed in both abdominal and pericardial adipose tissues. Circulating TNF-α increased in obese pigs only at 16 weeks. Compared with lean pigs, obese pigs had similar global cardiac function, but myocardial perfusion and oxygenation were significantly impaired.

CONCLUSIONS

A high-fat/high-fructose diet induces in domestic pigs many characteristics of metabolic syndrome, which is useful for investigating the effects of the obesity.

Differential Telomere Shortening in Blood versus Arteries in an Animal Model of Type 2 Diabetes

Vascular dysfunction is an early feature of diabetic vascular disease, due to increased oxidative stress and reduced nitric oxide (NO) bioavailability. This can lead to endothelial cell senescence and clinical complications such as stroke. Cells can become senescent by shortened telomeres and oxidative stress is known to accelerate telomere attrition. Sirtuin 1 (SIRT1) has been linked to vascular health by upregulating endothelial nitric oxide synthase (eNOS), suppressing oxidative stress, and attenuating telomere shortening. Accelerated leukocyte telomere attrition appears to be a feature of clinical type 2 diabetes (T2D) and therefore the telomere system may be a potential therapeutic target in preventing vascular complications of T2D. However the effect of T2D on vascular telomere length is currently unknown. We hypothesized that T2D gives rise to shortened leukocyte and vascular telomeres alongside reduced vascular SIRT1 expression and increased oxidative stress. Accelerated telomere attrition was observed in circulating leukocytes, but not arteries, in T2D compared to control rats. T2D rats had blunted arterial SIRT1 and eNOS protein expression levels which were associated with reduced antioxidant defense capacity. Our findings suggest that hyperglycemia and a deficit in vascular SIRT1 per se are not sufficient to prematurely shorten vascular telomeres.