Weight loss improves fasting flow-mediated vasodilation in adults: a meta-analysis of intervention studies

Exercise Training Improves Brachial Artery Endothelial Function, but Does Not Alter Inflammatory Biomarkers in Patients with Peripheral Artery Disease: a Systematic Review and Meta-analysis

The study aimed to systematically review the effects of exercise training (EX) on brachial artery flow-mediated dilation (FMD) and inflammatory biomarkers in patients with peripheral artery disease (PAD). Five electronic databases were searched: (i) patients with PAD aged ≥ 18; (ii) structured EX ≥ 2 weeks; (iii) measured brachial artery FMD; and (iv) measured blood inflammatory biomarkers. Eighteen studies met the inclusion criteria. EX increased FMD but had no effect on C-reactive protein, interleukin-6, and tumor necrosis factor-α. Subgroups with moderate intensity had a greater increase in FMD than subgroups with vigorous intensity. There was no difference in effect on FMD and three inflammatory biomarkers between subgroups training for ≤ 12 weeks and > 12 weeks of EX, < 50 min and ≥ 50 min of session duration, and < 150 min and ≥ 150 min of weekly volume, respectively. These results suggest that EX-induced improvement in vascular function can be independent of the improvement of systemic inflammation.

The Effect of Diet on Vascular Aging: A Narrative Review of the Available Literature

Early vascular aging is related to various cardiovascular diseases including hypertension, coronary heart disease, and stroke. Healthful lifestyle practices and interventions, including dietary regimens and consistent aerobic exercise, exert favorable modulation on these processes, thereby diminishing the risk of cardiovascular disease with advancing age. The principal objective of this review was to conduct a comprehensive evaluation and synthesis of the available literature regarding the effectiveness of different diets on vascular health, such as arterial stiffness and endothelial function. To conduct this review, a thorough search of electronic databases including PubMed, Scopus, and Web of Science Core Collection was carried out. Based on the existing evidence, the Mediterranean, Dietary Approaches to Stop Hypertension, and low-calorie diets may have a beneficial effect on vascular health. However, more randomized controlled trials with sufficient sample sizes, longer follow-ups, rigorous methodologies, and, possibly, head-to-head comparisons between the different diets are needed to shed light on this topic.

Antifibrotic effects of sodium-glucose cotransporter-2 inhibitors: A comprehensive review

BACKGROUND AND AIMS

Scar tissue accumulation in organs is the underlying cause of many fibrotic diseases. Due to the extensive array of organs affected, the long-term nature of fibrotic processes and the large number of people who suffer from the negative impact of these diseases, they constitute a serious health problem for modern medicine and a huge economic burden on society. Sodium-glucose cotransporter-2 inhibitors (SGLT2is) are a relatively new class of anti-diabetic pharmaceuticals that offer additional benefits over and above their glucose-lowering properties; these medications modulate a variety of diseases, including fibrosis. Herein, we have collated and analyzed all available research on SGLT2is and their effects on organ fibrosis, together with providing a proposed explanation as to the underlying mechanisms.

METHODS

PubMed, ScienceDirect, Google Scholar and Scopus were searched spanning the period from 2012 until April 2023 to find relevant articles describing the antifibrotic effects of SGLT2is.

RESULTS

The majority of reports have shown that SGLT2is are protective against lung, liver, heart and kidney fibrosis as well as arterial stiffness. According to the results of clinical trials and animal studies, many SGLT2 inhibitors are promising candidates for the treatment of fibrosis. Recent studies have demonstrated that SGLT2is affect an array of cellular processes, including hypoxia, inflammation, oxidative stress, the renin-angiotensin system and metabolic activities, all of which have been linked to fibrosis.

CONCLUSION

Extensive evidence indicates that SGLT2is are promising treatments for fibrosis, demonstrating protective effects in various organs and influencing key cellular processes linked to fibrosis.

Impact of bariatric surgery on carotid intima-media thickness, flow-mediated dilation, and nitrite-mediated dilation: a systematic review and meta-analysis

Obesity is considered one of the independent risk factors for atherosclerosis and is strongly correlated with cardiovascular morbidity and mortality. Previous studies showed carotid intima-media thickness (CIMT), flow-mediated dilation (FMD), and nitrite-mediated dilatation (NMD) are reliable non-invasive markers of arterial damage and dysfunction. The aim of this study was to evaluate the effect of bariatric surgery on CIMT, FMD, and NMD markers in patients with obesity. A systematic search was performed in the PubMed, Embase, Scopus, and Web of Science databases until May 2022. All the English-published studies on the effect of bariatric surgery on CIMT, FMD, and NMD were included. A quantitative meta-analysis was performed, as well as subgroup analyses for the type of procedure and duration of follow-up. Meta-analysis of 41 studies with 1639 patients showed CIMT was significantly reduced by .11 mm after bariatric surgery (95% CI, -.14 to -.08; P < .001; mean follow-up = 10.8 mo). The pooled analysis of 23 studies with 1106 patients showed an increase of FMD by 4.57% after bariatric surgery (95% CI, 2.69-6.44; P < .001; mean follow-up = 11.5 mo). The results of a pooled analysis of 12 studies with 346 patients showed a significant increase of NMD by 2.46% after bariatric surgery (95% CI, .99-3.94; P < .001; mean follow-up = 11.4 mo). The random effect meta-regression demonstrated that baseline CIMT and FMD significantly affect the changes in CIMT and FMD. This meta-analysis showed bariatric surgery can improve CIMT, FMD, and NMD markers in patients with obesity. These improvements show the known effect of metabolic surgery in decreasing cardiovascular risk.

Effects of dietary-based weight loss interventions on biomarkers of endothelial function: a systematic review and meta-analysis

Endothelial dysfunction is closely linked to the development of atherosclerosis. This systematic review and meta-analysis reviewed the evidence on the effect of weight loss, achieved by dietary-based interventions, on biomarkers of endothelial function (EF). Two databases (Medline, Embase) were searched from inception until November 2022 for studies that met the following criteria: 1) adult subjects (≥ 18 years) without exclusion for health status, 2) dietary interventions for weight loss, and 3) measurements of changes in EF biomarkers. Random-effect meta-analysis and meta-regression were performed. Thirty-seven articles including 1449 participants were included in the systematic review. Study duration ranged from 3-52 weeks. Overall, weight loss significantly improved biomarkers of EF [standardised mean difference (SMD):0.65; 95%CI:0.49,0.81; P < 0.001;I2 = 91.9%]. Subgroup analyses showed weight loss significantly improved levels of E-selectin (P < 0.001), intercellular adhesion molecule-1 (ICAM-1) (P < 0.001), vascular cell adhesion molecule-1 (VCAM-1) (P < 0.001), nitrite/nitrate (NOx) (P < 0.001) and vascular endothelial growth factor (VEGF) (P < 0.001). Conversely, there was no significant improvement for von Willebrand Factor (vWF). Meta-regression analysis revealed that changes in EF biomarkers were not affected by age, BMI, quality of the studies or the amount of weight lost. A significant heterogeneity was observed for the effects of weight loss on changes in EF biomarkers. Dietary-induced weight loss may be associated with biomarkers changes indicating an improvement of EF, and it may represent a potential strategy to reduce atherosclerotic risk.

Effect of aerobic and resistance exercise training on endothelial function in individuals with overweight and obesity: a systematic review with meta-analysis of randomized clinical trials

The objective of this systematic review was to examine the effects of exercise training on endothelial function in individuals with overweight and obesity. Our review study included only randomized controlled trials (RCTs) involving adults (≥ 18 years of age) with body mass index (BMI) ≥ 25.0 kg/m₂. Our search was conducted in the electronic bases MEDLINE (PubMed), Cochrane, LILACS and EMBASE and in the gray literature. We performed random-effects analyses for effect estimates and used 95% prediction intervals (95% PI) for estimating the uncertainty of the study results. There were selected 10 RCTs involving 14 groups (n = 400). The quality assessment of studies using Cochrane risk-of-bias 2 (RoB 2) tool identified some concerns. Exercise training resulted in improved flow-mediated dilation (FMD) in individuals with overweight and obesity (p < 0.001) compared to the no-exercise control group. This effect of training modalities on FMD was seen for aerobic training (p < 0.001) but not for resistance training (p = 0.051). There was no difference in FMD in response to exercise training by BMI classification (overweight, obesity, overweight + obesity), p = 0.793. The present results are consistent with the notion that aerobic exercise training elicits favorable adaptations in endothelial function in individuals with overweight and obesity. Our findings should be interpreted with caution because of the small number of studies included in this review.

High-intensity interval training improves the vascular endothelial function comparing moderate-intensity interval training in overweight or obese adults: A meta-analysis

OBJECTIVE

Obesity is associated with endothelial dysfunction and cardiovascular diseases. Moderate-intensity continuous training (MICT) is a common method to improve endothelial function and the cardiovascular risk profile in obesity. However, in recent times, high-intensity interval training (HIIT) has become a popular alternative for MICT primarily because of its time efficiency. Therefore, we hypothesized that HIIT is superior to MICT in improving vascular function. We aimed to evaluate this hypothesis by conducting a meta-analysis and quantifying the effect of HIIT on flow-mediated dilation (FMD) in overweight/obese adults.

METHODS

Databases (Scopus, Web of Science, and PubMed) were searched up to January 2022 for HIIT vs. moderate-intensity interval training (MICT) and HIIT vs. control (CON) studies on endothelial function assessed by flow-mediated dilation (FMD) in overweight and obese adults. From the included studies, standardized mean difference (SMD) and 95% confidence intervals (95% CIs) were calculated.

RESULTS

8 studies with 208 participants were included in this meta-analysis. According to the 6 studies, HIIT improved the FMD with an overall change of %2.6 [(95% CI: 0.82 to 4.377), p = 0.004] compared to the MICT in overweight and obese adults. Moreover, based on the 5 studies that compared HIIT and CON, the results showed HIIT significantly increased FMD by 1.83% [(95% CI: 0.478 to 3.187), p = 0.008].

CONCLUSIONS

These results showed that exercise training, particularly HIIT, could improve endothelial function in overweight and obese adults.

Comparative effects of weight loss and incretin-based therapies on vascular endothelial function, fibrinolysis and inflammation in individuals with obesity and prediabetes: A randomized controlled trial

AIM

To test the hypothesis that glucagon-like peptide-1 receptor (GLP-1R) agonists have beneficial effects on vascular endothelial function, fibrinolysis and inflammation through weight loss-independent mechanisms.

MATERIALS AND METHODS

Individuals with obesity and prediabetes were randomized to 14 weeks of the GLP-1R agonist liraglutide, hypocaloric diet or the dipeptidyl peptidase-4 inhibitor sitagliptin in a 2:1:1 ratio. Treatment with drug was double blind and placebo-controlled. Measurements were made at baseline, after 2 weeks prior to significant weight loss and after 14 weeks. The primary outcomes were measures of endothelial function: flow-mediated vasodilation (FMD), plasminogen activator inhibitor-1 (PAI-1) and urine albumin-to-creatinine ratio (UACR).

RESULTS

Eighty-eight individuals were studied (liraglutide N = 44, diet N = 22, sitagliptin N = 22). Liraglutide and diet reduced weight, insulin resistance and PAI-1, while sitagliptin did not. There was no significant effect of any treatment on endothelial vasodilator function measured by FMD. Post hoc subgroup analyses in individuals with baseline FMD below the median, indicative of greater endothelial dysfunction, showed an improvement in FMD by all three treatments. GLP-1R antagonism with exendin (9-39) increased fasting blood glucose but did not change FMD or PAI-1. There was no effect of treatment on UACR. Finally, liraglutide, but not sitagliptin or diet, reduced the chemokine monocyte chemoattractant protein-1 (MCP-1).

CONCLUSION

Liraglutide and diet reduce weight, insulin resistance and PAI-1. Liraglutide, sitagliptin and diet do not change FMD in obese individuals with prediabetes with normal endothelial function. Liraglutide alone lowers the pro-inflammatory and pro-atherosclerotic chemokine MCP-1, indicating that this beneficial effect is independent of weight loss.

Effect of high-intensity interval walking on microvascular endothelial function among community-dwelling older people

AIM

To investigate the effects of high-intensity interval exercise training on microvascular endothelial function among community-dwelling older people.

METHODS

We analyzed the data from a nonrandomized controlled trial. This study's participants were 48 men (aged 75 ± 5 years; exercise training group, n = 24; control group, n = 24) and 83 women (aged 75 ± 4 years; exercise training group, n = 36; control group, n = 47). The exercise training group underwent a high-intensity interval walking training for 5 months.

RESULTS

In the exercise group, 100% and 91.7% of men and women, respectively, achieved brisk walking times ≥50 min/week. The change in the reactive hyperemia index significantly differed between the groups of men, whereas that in the control group was not significant; however, a significant increase was observed in the exercise training group. Among women, changes in the reactive hyperemia index were not significant in either group; however, for women in the exercise training group, these changes negatively and positively correlated with the change in body mass index (Spearman's rho = -0.342; P = 0.041) and baseline body mass index (rho = 0.362, P = 0.030), respectively. Additionally, the distribution of body mass index was broader in women than in men.

CONCLUSIONS

Interval walking training increased the reactive hyperemia index in men rather than in women. A higher variation in baseline body mass index may be associated with no statistical increase in reactive hyperemia index in women. Geriatr Gerontol Int 2023; 23: 103-110.

Impact of Non-Pharmacological Interventions on the Mechanisms of Atherosclerosis

Atherosclerosis remains the leading cause of mortality and morbidity worldwide characterized by the deposition of lipids and fibrous elements in the form of atheroma plaques in vascular areas which are hemodynamically overloaded. The global burden of atherosclerotic cardiovascular disease is steadily increasing and is considered the largest known non-infectious pandemic. The management of atherosclerotic cardiovascular disease is increasing the cost of health care worldwide, which is a concern for researchers and physicians and has caused them to strive to find effective long-term strategies to improve the efficiency of treatments by managing conventional risk factors. Primary prevention of atherosclerotic cardiovascular disease is the preferred method to reduce cardiovascular risk. Fasting, a Mediterranean diet, and caloric restriction can be considered useful clinical tools. The protective impact of physical exercise over the cardiovascular system has been studied in recent years with the intention of explaining the mechanisms involved; the increase in heat shock proteins, antioxidant enzymes and regulators of cardiac myocyte proliferation concentration seem to be the molecular and biochemical shifts that are involved. Developing new therapeutic strategies such as vagus nerve stimulation, either to prevent or slow the disease’s onset and progression, will surely have a profound effect on the lives of millions of people.

Obesity and Endothelial Function

Obesity is a major public health problem and is related to increasing rates of cardiovascular morbidity and mortality. Over 1.9 billion adults are overweight or obese worldwide and the prevalence of obesity is increasing. Obesity influences endothelial function through obesity-related complications such as hypertension, dyslipidemia, diabetes, metabolic syndrome, and obstructive sleep apnea syndrome. The excess fat accumulation in obesity causes adipocyte dysfunction and induces oxidative stress, insulin resistance, and inflammation leading to endothelial dysfunction. Several anthropometric indices and imaging modalities that are used to evaluate obesity have demonstrated an association between obesity and endothelial function. In the past few decades, there has been great focus on the mechanisms underlying endothelial dysfunction caused by obesity for the prevention and treatment of cardiovascular events. This review focuses on pathophysiological mechanisms of obesity-induced endothelial dysfunction and therapeutic targets of obesity.

Effect of Bariatric Surgery on Flow-Mediated Vasodilation as a Measure of Endothelial Function: A Systematic Review and Meta-Analysis

Objectives. Flow mediated vasodilation (FMD) is a marker of endothelial function and its decline is related to increased cardiovascular risk. This systematic review and meta-analysis evaluated the impact of bariatric surgery on FMD. Materials and methods. A systematic literature search in PubMed, Scopus, Embase, and Web of Science was performed to 1 May 2021. Meta-analysis was performed using Comprehensive Meta-Analysis (CMA) V2 software. All types of bariatric surgery were considered, with the inclusion that FMD had to have been tested before and after the surgical procedure. Meta-analysis was carried out using a random-effects model and the generic inverse variance approach. The leave-one-out approach was used for sensitivity analysis. To assess metabolic parameter confounders, a weighted random-effects meta-regression was used. Results. A meta-analysis and a systematic review of 23 studies (n = 891 individuals) demonstrated improvement in FMD following bariatric surgery (weighted mean difference (WMD): 5.867, 95% CI: 4.481, 7.252, p < 0.001; I2: 96.70). Iteratively removing each item in the meta-analysis did not result in a significant alteration in the pooled estimate of effect size. There was an improvement in FMD for up to 6 months following bariatric surgery in a meta-analysis from 7 trials that included 356 subjects (WMD: 5.248, 95% CI: 2.361, 8.135, p < 0.001; I2: 98.18). The meta-analysis from 9 trials (n = 414 subjects) showed an improvement in FMD 6 to 12 months after bariatric surgery (WMD: 5.451, 95% CI: 3.316, 7.587, p < 0.001; I2: 94.18). The meta-analysis from 10 trials (n = 414 subjects) demonstrated an improvement in FMD 12 months after bariatric surgery (WMD: 2.401, 95% CI: 0.944, 3.859, p = 0.001; I2: 88.35). Random-effects meta-regression did not show any association between the alteration in FMD and percent body mass index (BMI) change (slope: 0.0258; 95% CI: −0.323, 0.375; p = 0.884), or changes in blood pressure; however, there was an association between the changes in FMD and the duration of follow-up (slope: −0.106; 95% CI: −0.205, −0.008; p = 0.033) with greater changes in FMD after 12 months. Conclusions. Bariatric surgery significantly improved FMD that increased with time, and the resultant improvement in endothelial function was independent of weight loss or a reduction in blood pressure.

Effects of aquatic high-intensity interval training and moderate-intensity continuous training on central hemodynamic parameters, endothelial function and aerobic fitness in inactive adults

Objective

The effects of land-based high-intensity interval training (HIIT) on the cardiovascular system have already been demonstrated. However, the water environment is different from that on land. Therefore, we investigated the effects of 6-week aquatic HIIT and moderate-intensity continuous training (MICT) on central hemodynamic parameters, endothelial function, and aerobic fitness in inactive adults.

Methods

Thirty-one inactive adults were randomly assigned to HIIT or MICT group. HIIT group performed twelve 30-s swimming exercise bouts with the intensity of 95% HR_max and 15-18/20 RPE with a 60-s rest period between each bout. MICT group performed a 30-min uninterrupted swimming exercise with the intensity of 70%-75% HR_max and 12-14/20 RPE. Training frequency for both groups was three times a week. The pulse wave analysis and flow-mediated dilation (FMD) were measured by non-invasive equipments.

Results

The aerobic fitness significantly increased after HIIT, but no change was seen after MICT. Augmentation pressure (AP) and augmentation index normalized at 75 bpm (AIx@HR75) significantly decreased after HIIT but not MICT, whereas MICT rather than HIIT improved subendocardial viability ratio (SEVR), central and peripheral blood pressure, and resting HR. Only HIIT significantly increased brachial endothelial function.

Conclusion

A six-week aquatic HIIT and MICT had no differences in hemodynamic parameters, endothelial function, and aerobic fitness, however 6 weeks of aquatic HIIT reduced arterial stiffness, increased endothelial function and aerobic fitness, while 6 weeks of aquatic MICT reduced arterial blood pressure and resting HR and increased the coronary blood flow reserve.

Obesity treatment: Weight loss versus increasing fitness and physical activity for reducing health risks

We propose a weight-neutral strategy for obesity treatment on the following grounds: (1) the mortality risk associated with obesity is largely attenuated or eliminated by moderate-to-high levels of cardiorespiratory fitness (CRF) or physical activity (PA), (2) most cardiometabolic risk markers associated with obesity can be improved with exercise training independent of weight loss and by a magnitude similar to that observed with weight-loss programs, (3) weight loss, even if intentional, is not consistently associated with lower mortality risk, (4) increases in CRF or PA are consistently associated with greater reductions in mortality risk than is intentional weight loss, and (5) weight cycling is associated with numerous adverse health outcomes including increased mortality. Adherence to PA may improve if health care professionals consider PA and CRF as essential vital signs and consistently emphasize to their patients the myriad benefits of PA and CRF in the absence of weight loss.

Comparison of Resveratrol Supplementation and Energy Restriction Effects on Sympathetic Nervous System Activity and Vascular Reactivity: A Randomized Clinical Trial

Background: Chronic sympathetic nervous system activation is associated with endothelial dysfunction and cardiometabolic disease, which may be modulated by resveratrol (RSV) and energy restriction (ER). This study aimed to examine the effects of RSV and ER on plasma noradrenaline (NA), flow-mediated vasodilation (ed-FMD), and endothelium-independent nitrate-mediated vasodilation (ei-NMD). Methods: The study included 48 healthy adults randomized to 30-days intervention of RSV or ER. Results: Waist circumference, total cholesterol, HDL-c, LDL-c, apoA-I, and plasma NA decreased in the ER group, whilst RSV increased apoB and total cholesterol, without changing plasma NA. No effects on vascular reactivity were observed in both groups. Plasma NA change was positively correlated with total cholesterol (r = 0.443; p = 0.002), triglycerides (r = 0.438; p = 0.002), apoA-I (r = 0.467; p = 0.001), apoB (r = 0.318; p = 0.032) changes, and ei-NMD (OR = 1.294; 95%CI: 1.021–1.640). Conclusions: RSV does not improve cardiometabolic risk factors, sympathetic activity, and endothelial function. ER decreases plasma NA and waist circumference as well as improves blood lipids, but does not modify endothelial function. Finally, plasma NA was associated with ei-NMD, which could be attributed to a higher response to nitrate in patients with greater resting sympathetic vasoconstriction.

Acute hyperglycaemia enhances both vascular endothelial function and cardiac and skeletal muscle microvascular function in healthy humans

KEY POINTS

Multiple clinical studies report that acute hyperglycaemia (induced by mixed meal or oral glucose) decreases arterial vascular function in healthy humans. Feeding, however, impacts autonomic output, blood pressure, and insulin and incretin secretion, which may themselves alter vascular function. No prior studies have examined the effect of acute hyperglycaemia on both macro- and microvascular function while controlling plasma insulin concentrations. Macrovascular and microvascular functional responses to euglycaemia and hyperglycaemia were compared. Octreotide was infused throughout both protocols to prevent endogenous insulin release. Acute hyperglycaemia (induced by intravenous glucose) enhanced brachial artery flow-mediated dilatation, increased skeletal muscle microvascular blood volume and flow, and expanded cardiac muscle microvascular blood volume. Compared to other published findings, the results suggest that vascular responses to acute hyperglycaemia differ based on the study population (i.e. normal weight vs. overweight/obese) and/or glucose delivery method (i.e. intravenous vs. oral glucose).

ABSTRACT

High glucose concentrations acutely provoke endothelial cell oxidative stress and are suggested to trigger diabetes-related macro- and microvascular injury in humans. Multiple clinical studies report that acute hyperglycaemia (induced by mixed meal or oral glucose) decreases arterial vascular function in healthy humans. Feeding, however, impacts autonomic output, blood pressure, and insulin and incretin secretion, which may each independently alter vascular function and obscure the effect of acute hyperglycaemia per se. Surprisingly, no studies have examined the acute effects of intravenous glucose-induced hyperglycaemia on both macro- and microvascular function while controlling plasma insulin concentrations. In this randomized study of healthy young adults, we compared macrovascular (i.e. brachial artery flow-mediated dilatation, carotid-femoral pulse wave velocity and post-ischaemic brachial artery flow velocity) and microvascular (heart and skeletal muscle perfusion by contrast-enhanced ultrasound) functional responses to euglycaemia and hyperglycaemia. Octreotide was infused throughout both protocols to prevent endogenous insulin release. Acute intravenous glucose-induced hyperglycaemia enhanced brachial artery flow-mediated dilatation (P = 0.004), increased skeletal muscle microvascular blood volume and flow (P = 0.001), and expanded cardiac muscle microvascular blood volume (P = 0.014). No measure of vascular function changed during octreotide-maintained euglycaemia. Our findings suggest that unlike meal-provoked acute hyperglycaemia, 4 h of intravenous glucose-induced hyperglycaemia enhances brachial artery flow-mediated dilatation, provokes cardiac and skeletal muscle microvascular function, and does not impair aortic stiffness. Previous findings of acute large artery vascular dysfunction during oral glucose or mixed meal ingestion may be due to differences in study populations and meal-induced humoral or neural factors beyond hyperglycaemia per se. (ClinicalTrials.gov number NCT03520569.).

Lifestyle interventions for the prevention and treatment of hypertension

Hypertension affects approximately one third of the world's adult population and is a major cause of premature death despite considerable advances in pharmacological treatments. Growing evidence supports the use of lifestyle interventions for the prevention and adjuvant treatment of hypertension. In this Review, we provide a summary of the epidemiological research supporting the preventive and antihypertensive effects of major lifestyle interventions (regular physical exercise, body weight management and healthy dietary patterns), as well as other less traditional recommendations such as stress management and the promotion of adequate sleep patterns coupled with circadian entrainment. We also discuss the physiological mechanisms underlying the beneficial effects of these lifestyle interventions on hypertension, which include not only the prevention of traditional risk factors (such as obesity and insulin resistance) and improvements in vascular health through an improved redox and inflammatory status, but also reduced sympathetic overactivation and non-traditional mechanisms such as increased secretion of myokines.

Treatment of Obesity in Mitigating Metabolic Risk

Through diverse mechanisms, obesity contributes to worsened cardiometabolic health and increases rates of cardiovascular events. Effective treatment of obesity is necessary to reduce the associated burdens of diabetes mellitus, cardiovascular disease, and death. Despite increasing cardiovascular outcome data on obesity interventions, only a small fraction of the population with obesity are optimally treated. This is a primary impetus for this article in which we describe the typical weight loss, as well as the associated impact on both traditional and novel cardiovascular disease risk factors, provided by the 4 primary modalities for obtaining weight loss in obesity-dietary modification, increasing physical activity, pharmacotherapy, and surgery. We also attempt to highlight instances where changes in metabolic risk are relatively specific to particular interventions and appear at least somewhat independent of weight loss. Finally, we suggest important areas for further research to reduce and prevent adverse cardiovascular consequences due to obesity.

cGMP manipulation in cardiometabolic disease: chances and challenges

PURPOSE OF REVIEW

Cardiovascular and metabolic diseases are closely linked and commonly occur in the same patients. This review focuses on the cyclic guanosine monophosphate (cGMP) system and its crosstalk between metabolism and the cardiovascular system.

RECENT FINDINGS

Recent studies suggest that cGMP, which serves as second messenger for nitric oxide and for natriuretic peptides, improves oxidative metabolism and insulin signaling. The clinical evidence is particularly strong for the natriuretic peptide branch of the cGMP system. Clinical trials suggested improvements in insulin sensitivity and reductions in the risk of progressing to type 2 diabetes mellitus. However, further studies are needed.

SUMMARY

Enhancing cGMP signaling through nonpharmacological or pharmacological means may improve glucose metabolism in addition to affecting the cardiovascular system. However, excessive cGMP production could have significant unwanted cardiovascular and metabolic effects.

Relationship between endothelium-dependent vasodilation and fat distribution using the new "imiomics" image analysis technique

BACKGROUND AND AIMS

We investigated how vasoreactivity in the brachial artery and the forearm resistance vessels were related to fat distribution and tissue volume, using both traditional imaging analysis and a new technique, called "Imiomics", whereby vasoreactivity was related to each of the >2M 3D image elements included in the whole-body magnetic resonance imaging (MRI).

METHODS AND RESULTS

In 326 subjects in the Prospective investigation of Obesity, Energy and Metabolism (POEM) study (all aged 50 years), endothelium-dependent vasodilation was measured by acetylcholine infusion in the brachial artery (EDV) and flow-mediated vasodilation (FMD). Fat distribution was evaluated by dual-energy X-ray absorptiometry (DXA) and magnetic resonance imaging (MRI). EDV, but not FMD, was significantly related to total fat mass, liver fat, subcutaneous (SAT) and visceral (VAT) adipose tissue in a negative fashion in women, but not in men. Using Imiomics, an inverse relationship was seen between EDV and a local tissue volume of SAT in both the upper part of the body, as well as the gluteo-femoral part and the medial parts of the legs in women. Also the size of the liver, heart and VAT was inversely related to EDV. In men, less pronounced relationships were seen. FMD was also significantly related to local tissue volume of upper-body SAT and liver fat in women, but less so in men.

CONCLUSION

EDV, and to a lesser degree also FMD, were related to liver fat, SAT and VAT in women, but less so in men. Imiomics both confirmed findings from traditional methods and resulted in new, more detailed results.

Endothelial function following interval exercise plus low-calorie diet treatment in obese females

We determined if interval exercise plus a low-calorie diet (LCD + INT) increases endothelial function more than an energy-matched LCD. Obese women (47.2 ± 2.6y, 37.5 ± 1.3kg/m2 ) were randomized to 13 days of a LCD (n = 12; mixed meals of ~ 1200kcal/d) or LCD + INT (n = 13; 12 supervised 60-min INT bouts of 3 min at 90% and 50% HRpeak ). LCD + INT subjects received 350kcal postexercise to equate energy availability with LCD. Fitness (VO2 peak) and body composition (BodPod) were determined and a 120 min, 75 g oral glucose tolerance test was performed to examine fasting and postprandial flow-mediated dilation (FMD, endothelial function), respiratory exchange ratio (RER) via indirect calorimetry as well as glucose and insulin incremental area under the curve (iAUC120min ). LCD + INT increased VO2 peak (P = 0.02) compared with LCD, and both treatments decreased fat mass (P < 0.001) and insulin iAUC120min (P = 0.03). There was no overall treatment effect on fasting or iAUC120min FMD. However, in participants who increased fasting endothelial function after each treatment (Δ > 50%; LCD n = 5, LCD + INT n = 7), LCD + INT increased fasted (P = 0.005) and decreased iAUC120min (P = 0.003) FMD compared with LCD. Enhanced fitness correlated with increased fasting FMD (r = 0.43, P = 0.03) and diminished FMD iAUC120min (r = -0.44, P = 0.03). Decreased FMD iAUC120min correlated with reduced glucose iAUC120min (r = 0.64, P = 0.001) as well as increased 60-min RER (r = -0.42, P = 0.04). Low baseline fasting and iAUC120min FMD was also linked to enhanced fasting and iAUC120min FMD post-treatment (r = -0.71, P < 0.001; r = -0.89, P < 0.001, respectively). In conclusion, increasing fitness via INT may increase the effect of LCD on lowering cardiovascular disease risk in obese women.

Acute Effects of Whole-Body Vibration Training on Endothelial Function and Cardiovascular Response in Elderly Patients with Cardiovascular Disease

The aim of this single-arm pilot study was to determine the effects of whole-body vibration training (WBVT) on endothelial function in elderly patients with cardiovascular diseases, as well as its safety. A total of 20 elderly patients with stable cardiovascular diseases underwent WBVT, which consisted of five static resistance training exercises (squats, wide stance squats, toe-stands, squats + band, and front lunges). The parameters of WBVT included vertical vibrations, 30 Hz frequency, and a 3-mm peak-to-peak amplitude. Each vibration session lasted 30 seconds, with 120 seconds of rest between sessions. Before and after WBVT, the reactive hyperemia peripheral arterial tonometry index (RH-PAT index) and transcutaneous oxygen pressure (tcPO₂) were recorded as a measure of endothelial function and peripheral blood circulation. Systolic blood pressure, diastolic blood pressure, heart rate, and arterial oxygen saturation of pulse oximetry (SpO₂) were measured at each rest interval as well as before and after WBVT. All patients completed our WBVT protocol without adverse events. The RH-PAT index significantly increased following WBVT (1.42 to 2.06, P < 0.001). There were no significant changes in heart rate (P = 0.777), systolic blood pressure (P = 0.183), diastolic blood pressure (P = 0.925), or SpO₂ (P = 0.248) during WBVT. In conclusion, we demonstrated the acute effects of WBVT on endothelial function, with no reports of adverse events. These findings support the need for further randomized controlled studies to investigate the long-term effects of WBVT.

Low-Fat Diet Designed for Weight Loss But Not Weight Maintenance Improves Nitric Oxide-Dependent Arteriolar Vasodilation in Obese Adults

Obesity is associated with microvascular dysfunction. While low-fat diet improves cardiovascular risk, its contributions on microvascular function, independent of weight loss, is unknown. We tested the hypothesis that nitric oxide (NO)-dependent vasodilation in microvessels is improved by low-fat diets designed for weight loss (LFWL) compared to low-fat weight maintenance (LFWM) diet. Obese adults were randomly assigned to either a LFWL diet (n = 11) or LFWM diet (n = 10) for six weeks. Microvessels were obtained from gluteal subcutaneous fat biopsies before and after the intervention for vascular reactivity measurements to acetylcholine (Ach) and flow, with and without L-NAME or indomethacin. Vascular and serum NO and C-reactive protein (CRP) were also measured. LFWL diet increased flow-induced (FID) and ACh-induced dilation (AChID); an effect that was inhibited by L-NAME. Conversely, LFWM diet did not affect FID or AChID. Indomethacin improved FID and AChID in the baseline and this effect was minimized in response to both diets. Serum NO or CRP did not change in response to either diet. In conclusion, LFWL diet improves microvascular reactivity compared to LFWM diet and increased vascular NO contribution to the improved microvascular dilation. These data suggest that weight reduction on low fat diet is critical for microvascular health.

Precision Measurements to Assess Baseline Status and Efficacy of Healthy Living Medicine

Precision medicine recently has gained popularity, calling for more individualized approaches to prevent and/or reduce chronic-disease risk and to reduce non-communicable diseases such as cardiovascular disease (CVD). Encompassed under Precision medicine initiatives is the concept of healthy living medicine (HLM), which emphasizes the promotion of lifestyle and behavioral practices including physical activity and healthy dietary pattern. Precision measurements have the potential to improve the understanding of how risk factors influence disease trajectory, and further inform on how to precisely tailor clinical strategies to manage risk factors to prevent disease manifestation, and refine therapies according the patient's demographic, environment, and disease etiology. The purpose of this review is to summarize the application of established and emerging measurements that may be used in HLM to manage and optimize care in CVD prevention.

Acute Endothelial Benefits of Fat Restriction over Carbohydrate Restriction in Type 2 Diabetes Mellitus: Beyond Carbs and Fats

Background: Cardiovascular diseases (CVD) are the major cause of mortality in type 2 diabetes patients (T2DM). The causes are embedded in a complex interplay between excess body fat, insulin resistance and serum lipid anomalies. Endothelial homeostasis is strongly affected by this pathogenic network. Even though metabolic changes and weight loss improve vascular endothelial function, the effect of different dietary approaches is still uncertain for type 2 diabetes patients. Objective: We aimed to compare the acute effects of a hypocaloric very low carbohydrate (VLC) diet versus a hypocaloric low fat (LF) diet on flow mediated dilation (FMD), intrahepatic lipid (IHL) accumulation and visceral adipose tissue as independent risk factors of CVD in T2DM patients. Design: 36 T2DM patients (age 63 ± 8 years, 60% females) were randomly assigned to the VLC diet (4–10% of total energy intake (E)) or to the LF diet (<30% E) for 3 weeks. Endothelial function was assessed by the flow mediated dilation (FMD) method. Adipose tissue depots and IHL were determined by magnetic resonance. Results: Both dietary strategies reduced body weight, body fat content and IHL. Unexpectedly, the LF group experienced significantly greater enhancement of FMD, compared to the VLC group. The FMD showed a positive correlation with protein intake and fat intake in the LF group, while it revealed a negative correlation with protein intake in the VLC diet group. Conclusions: Reduction of total and hepatic adiposity was shown to be successful using either the VLC or LF hypocaloric diets, however, improvements in FMD may be related to the interplay of fat and protein intake.

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.

Effect of Intermittent Energy Restriction on Flow Mediated Dilatation, a Measure of Endothelial Function: A Short Report

Intermittent energy restriction is a popular alternative to daily energy restriction for weight loss; however, it is unknown if endothelial function, a risk factor for cardiovascular disease, is altered by periods of severe energy restriction. The objective of the study was to determine the impact of two consecutive very low energy intake days, which is the core component of the 5:2 intermittent energy restriction diet strategy, on endothelial function compared to consecutive ad libitum eating days. The secondary objective was to explore the effects of these dietary conditions on fasting glucose concentrations. This was a 4-week randomized, single-blinded, crossover study of 35 participants. Participants consumed a very low energy diet (500 calories for women, 600 calories for men) on two consecutive days per week and 5 days of habitual eating. In weeks 3 and 4 of the trial, participants had measurements of flow mediated dilatation (FMD) and blood samples taken following either 2 habitual eating days or 2 energy restricted days in a randomized order. FMD values were not different after the two eating states (8.6% vs. 8.3%, p = 0.7). All other outcome variables were unchanged. Endothelial function, as measured by flow mediated dilatation, was not altered by two consecutive very low energy intake days. Further investigations assessing the impact in specific population groups as well as different testing conditions would be beneficial.

The effects of exercise on vascular endothelial function in type 2 diabetes: a systematic review and meta-analysis

BACKGROUND

Vascular endothelial dysfunction induced by hyperglycemia and elevated insulin resistance is a potent risk factor for cardiovascular disease and likely contributes to multiple chronic disease complications associated with aging. The aim of this study was to systematically review and quantify the effects of exercise on endothelial function (EF) in type 2 diabetes (T2D).

METHODS

Five electronic databases were searched (until June 2017) for studies that met the following criteria: (i) randomized controlled trials; (ii) T2D aged ≥ 18 years; (iii) measured EF by brachial artery flow-mediated dilation (FMD); (iv) structured and supervised exercise intervention for ≥ 8 weeks.

RESULTS

Thirteen cohorts, selected from eight studies (306 patients, average age 59 years), met the inclusion criteria. Exercise training significantly increased FMD (mean ES = 0.41, 95% CI 0.21-0.62, P < 0.001). Low to moderate intensity subgroups and aerobic exercise (AE) subgroups significantly increased FMD more than moderate to high intensity subgroups and combined AE and resistance exercise subgroups respectively (P < 0.01, P < 0.05). The Grading of Recommendations Assessment, Development and Evaluation (GRADE) assessments reported that quality of evidence for all outcomes was moderate except shear rate showing low. Egger's test showed no significant publication bias for all outcomes.

CONCLUSION

Our results suggest that in patients with T2D, lower intensity exercise has physiological meaningful effects on EF, in support of the emerging concept that the lower efforts of exercise are not necessarily less cardioprotective than higher intensity training.

Effect of Exercise Intervention on Flow-Mediated Dilation in Overweight and Obese Adults: Meta-Analysis

The objective of this meta-analysis is to summarize the effect of exercise intervention on flow-mediated dilatation (FMD) in overweight and obese adults. We searched four electronic databases (PubMed/Medline, Scopus, and CINAHL) through June 2016 for relevant studies pertaining to the effectiveness of exercise intervention on FMD. Seventeen of the 91 studies identified met the inclusion criteria. Comprehensive Meta-Analysis software (version 3) was used to compute the standardized mean difference effect size (ES) and 95% CI using a random effects model. We calculated 34 ESs. We found that exercise intervention had medium and positive effects on FMD, with an overall ES of 0.522 (95% CI = 0.257, 0.786). Heterogeneity of ESs was observed (Q_b = 239, p ≤ 0.001, I² = 86.19), and the effect was moderated by comorbidity (Q_b = 6.39, df = 1, p = 0.011). A large ES for the combination exercise, low intensity exercise, and comorbidity subgroups (ES = 0.82~1.24) was found. We conclude that while exercise intervention significantly improves FMD in overweight and obese adults, the effect may depend on the different characteristics of exercise intervention and on participants' demographics.

Exercise training with dietary restriction enhances circulating irisin level associated with increasing endothelial progenitor cell number in obese adults: an intervention study

Objective

Circulating endothelial progenitor cells (EPCs) correlate negatively with obesity. Previous studies have shown that exercise significantly restores circulating EPC levels in obese people; however, the underlying mechanisms have not been elucidated. Recently, irisin has been reported to have a critical role in the regulation of EPCs. This exercise-induced myokine has been demonstrated to play a therapeutic role in obesity. In this study, we hypothesized that the increase in circulating irisin may form a link with increasing EPC levels in obese people after exercise.

Methods

Seventeen obese adults completed an 8-week program of combined exercise and dietary intervention. Clinical characteristics, blood biochemistry, and circulating irisin levels of subjects were measured before and after eight weeks of training. EPC levels were evaluated via flow cytometry, and EPC migratory and adhesive functions were also determined.

Results

Circulating irisin levels significantly increased following the 8-week training program (P < 0.05). We furthermore observed an improvement in EPC numbers (P < 0.05), and EPC migratory and adhesive functions (P < 0.001 and P < 0.05, respectively) after the intervention. Additionally, we detected a positive correlation between changes in irisin and changes in EPC number (r = 0.52, P < 0.05).

Discussion

For the first time, a positive correlation between increasing irisin levels and increasing EPC levels has been reported after an 8-week program, consisting of exercise and dietary intervention. This result suggests a novel effect of irisin on the regulation of EPC mobilization, which might contribute to improvement of endothelial function in obese people.

Association Between Cardiovascular Health and Endothelial Function With Future Erectile Dysfunction: The Multi-Ethnic Study of Atherosclerosis

BACKGROUND

The association of Cardiovascular Health (CVH; defined by the American Heart Association by assigning points for health-related behavioral and clinical factors) with endothelial and erectile dysfunction has not been reported, although endothelial and erectile dysfunction have been associated with components of CVH.

METHODS

Data were collected in 1,136 men in the Multi-Ethnic Study of Atherosclerosis at baseline and erectile dysfunction status (measured by survey or medication use) at exam 5. CVH was determined with 7 health metrics. Endothelial function was measured with brachial artery flow-mediated dilation (FMD). Poisson regression was used to determine associations between CVH and erectile dysfunction across categories of CVH (low, moderate, and high).

RESULTS

Age and proportion of Black or Latino participants decreased while proportion of Chinese-American participants increased with higher CVH category. FMD was higher in men without erectile dysfunction and higher in men with high vs. low CVH. Erectile dysfunction prevalence was lower with better CVH; 58% in men with low CVH, 41% with moderate CVH, and 33% with high CVH (P < 0.001). CVH was associated with erectile dysfunction; prevalence ratio = 0.75 (95% confidence interval (CI) = 0.66, 0.84) with moderate CVH and 0.68 (95% CI = 0.49, 0.94) with high CVH (vs. men with low CVH) and 0.93 (95% CI = 0.91, 0.96) for every 1-point higher CVH score in a fully adjusted model, including FMD, age, education, depression score, use of antidepressant or beta-blocker medications, chronic disease, heavy drinking, and race.

CONCLUSION

CVH is associated with future erectile dysfunction, even after adjustment for baseline FMD. Maintaining high CVH may improve quality of life for men.

Effect of a long-term intensive lifestyle intervention on prevalence of cognitive impairment

OBJECTIVE

To assess whether an average of 10 years of lifestyle intervention designed to reduce weight and increase physical activity lowers the prevalence of cognitive impairment among adults at increased risk due to type 2 diabetes and obesity or overweight.

METHODS

Central adjudication of mild cognitive impairment and probable dementia was based on standardized cognitive test battery scores administered to 3,802 individuals who had been randomly assigned, with equal probability, to either the lifestyle intervention or the diabetes support and education control. When scores fell below a prespecified threshold, functional information was obtained through proxy interview.

RESULTS

Compared with control, the intensive lifestyle intervention induced and maintained marked differences in weight loss and self-reported physical activity throughout follow-up. At an average (range) of 11.4 (9.5-13.5) years after enrollment, when participants' mean age was 69.6 (54.9-87.2) years, the prevalence of mild cognitive impairment and probable dementia was 6.4% and 1.8%, respectively, in the intervention group, compared with 6.6% and 1.8%, respectively, in the control group (p = 0.93). The lack of an intervention effect on the prevalence of cognitive impairment was consistent among individuals grouped by cardiovascular disease history, diabetes duration, sex, and APOE ε4 allele status (all p ≥ 0.50). However, there was evidence (p = 0.03) that the intervention effect ranged from benefit to harm across participants ordered from lowest to highest baseline BMI.

CONCLUSIONS

Ten years of behavioral weight loss intervention did not result in an overall difference in the prevalence of cognitive impairment among overweight or obese adults with type 2 diabetes.

CLINICALTRIALSGOV IDENTIFIER

NCT00017953 (Action for Health in Diabetes).

LEVEL OF EVIDENCE

This study provides Class II evidence that for overweight adults with type 2 diabetes, a lifestyle intervention designed to reduce weight and increase physical activity does not lower the risk of cognitive impairment.

Obesity, arterial function and arterial structure - a systematic review and meta-analysis

OBJECTIVE

Obesity is an established risk factor for cardiovascular disease. The mechanisms by which obesity affects cardiovascular risk have not been fully elucidated. This paper reports a comprehensive systematic review and meta-analysis on obesity and two key aspects of vascular health using gold-standard non-invasive measures - arterial endothelial function (brachial flow-mediated dilatation) and subclinical atherosclerosis (carotid intima-media thickness).

METHODS

Electronic searches for 'Obesity and flow-mediated dilatation' and 'Obesity and intima-media thickness' were performed using Ovid Medline and Embase databases. A meta-analysis was undertaken for brachial flow-mediated dilatation and carotid intima-media thickness to obtain pooled estimates for adults with obesity and those with healthy weight.

RESULTS

Of the 5,810 articles retrieved, 19 studies on flow-mediated dilatation and 19 studies on intima-media thickness were included. Meta-analysis demonstrated that obesity was associated with lower flow-mediated dilatation (-1.92 % [95% CI -2.92, -0.92], P = 0.0002) and greater carotid intima-media thickness (0.07 mm [95% CI 0.05, 0.08], P < 0.0001).

CONCLUSIONS

Obesity is associated with poorer arterial endothelial function and increased subclinical atherosclerosis, consistent with these aspects of vascular health at least partially contributing to the increased risk of cardiovascular events in adults with obesity. These estimated effect sizes will enable vascular health benefits in response to weight loss treatment to be put in greater perspective, both in the research setting and potentially also clinical practice.

Weight loss and carotid intima-media thickness-a meta-analysis

OBJECTIVE

Obesity is a risk factor for clinical cardiovascular disease, putatively via increased burden of atherosclerosis. It remains contentious as to whether weight loss in people with obesity is accompanied by a reduction in intima-media thickness, a noninvasive marker of subclinical atherosclerosis, consistent with a lowering of risk of cardiovascular events.

METHODS

A systematic literature search was performed to identify all surgical and nonsurgical weight loss interventions that reported intima-media thickness. A meta-analysis was undertaken to obtain pooled estimates for change in intima-media thickness.

RESULTS

From the 3,197 articles screened, 9 studies were included in the meta-analysis, with a total of 393 participants who lost an average of 16 kg (95% CI 9.4-22.5) of body weight over an average follow-up of 20 months. The pooled mean change in carotid intima-media thickness was -0.03 mm (95% CI -0.05 to -0.01), which was similar between surgical and nonsurgical interventions.

CONCLUSIONS

In people with obesity, weight loss was associated with a reduction in carotid intima-media thickness, consistent with a lowering in risk of cardiovascular events.

Diet-induced weight loss improves not only cardiometabolic risk markers but also markers of vascular function: a randomized controlled trial in abdominally obese men

BACKGROUND

Many trials assessing effects of dietary weight loss on vascular function have been performed without no-weight loss control groups and in individuals with obesity-related morbidities. Usually a limited set of vascular function markers has been investigated.

OBJECTIVE

The objective of this study was to examine effects of diet-induced weight loss on various vascular function markers and differences between normal-weight and abdominally obese men at baseline and after weight reduction.

DESIGN

Twenty-five healthy, normal-weight men (waist circumference: <94 cm) and 54 abdominally obese men (waist circumference: 102-110 cm) participated. Abdominally obese participants were randomly allocated to a dietary weight-loss or a no-weight loss control group. Individuals from the weight-loss group followed a calorie-restricted diet for 6 wk to obtain a waist circumference <102 cm followed by a weight-maintenance period of 2 wk. The control group maintained their habitual diet and physical activity levels. The primary outcome was the change in brachial artery flow-mediated vasodilation (FMD).

RESULTS

Compared with the control group, FMD did not change in the weight-loss group, but carotid-to-femoral pulse wave velocity tended to decrease by 0.5 m/s (P = 0.065). The retinal arteriolar caliber increased by 5 μm (P < 0.001) and the arteriolar-to-venular ratio by 0.02 (P < 0.01). Soluble endothelial selectin and soluble intercellular adhesion molecule concentrations decreased (P < 0.001). Also, total cholesterol, low-density lipoprotein cholesterol, triacylglycerol, glucose, insulin, C-peptide, homeostasis model assessment of insulin resistance, and blood pressure improved (P < 0.05 for all variables). Except for FMD, these markers differed at baseline between normal-weight and abdominally obese men but became comparable after weight loss.

CONCLUSIONS

In abdominally obese men, dietary weight loss targeting a waist circumference of <102 cm improved retinal microvascular caliber, plasma biomarkers of microvascular endothelial function, and the more conventional cardiometabolic risk markers. Aortic stiffness tended to decrease, but FMD was not changed. This trial was registered at clinicaltrials.gov as NCT01675401.

Long-term effects of weight loss with a very-low carbohydrate, low saturated fat diet on flow mediated dilatation in patients with type 2 diabetes: A randomised controlled trial

BACKGROUND AND AIMS

Very-low carbohydrate diets can improve glycaemic control in patients with type 2 diabetes (T2DM). However, compared to traditional higher carbohydrate, low fat (HighCHO) diets, they have been associated with impaired endothelial function (measured by flow mediated dilatation [FMD]) that is possibly related to saturated fat. This study aimed to examine the effects of a 12-month hypocaloric very-low carbohydrate, low saturated fat (LowCHO) diet compared to an isocaloric HighCHO diet.

METHODS

One hundred and fifteen obese patients with T2DM (age:58.4 ± 0.7 [SEM] yr, BMI:34.6 ± 0.4 kg/m(2), HbA1c:7.33 [56.3 mmol/mol] ± 0.10%) were randomised to consume an energy restricted LowCHO diet (Carb:Pro:Fat:Sat-Fat 14:28:58: < 10% energy; n = 58) or isocaloric HighCHO diet (53:17:30: < 10%; n = 57) whilst undertaking exercise (60 min, 3/wk). Bodyweight, HbA1c and FMD were assessed.

RESULTS

Seventy eight participants completed the intervention (LowCHO = 41, HighCHO = 37). Both groups experienced similar reductions in weight and HbA1c (-10.6 ± 0.7 kg, -1.05 ± 0.10%; p < 0.001 time, p ≥ 0.48 time × diet). FMD did not change (p = 0.11 time, p = 0.20 time × diet).

CONCLUSIONS

In patients with obesity and T2DM, HighCHO diet and LowCHO diet have similar effects on endothelial function.

Effects of high-intensity interval training and moderate-intensity continuous training on endothelial function and cardiometabolic risk markers in obese adults

We hypothesized that high-intensity interval training (HIIT) would be more effective than moderate-intensity continuous training (MICT) at improving endothelial function and maximum oxygen uptake (V̇o2 max) in obese adults. Eighteen participants [35.1 ± 8.1 (SD) yr; body mass index = 36.0 ± 5.0 kg/m(2)] were randomized to 8 wk (3 sessions/wk) of either HIIT [10 × 1 min, 90-95% maximum heart rate (HRmax), 1-min active recovery] or MICT (30 min, 70-75% HRmax). Brachial artery flow-mediated dilation (FMD) increased after HIIT (5.13 ± 2.80% vs. 8.98 ± 2.86%, P = 0.02) but not after MICT (5.23 ± 2.82% vs. 3.05 ± 2.76%, P = 0.16). Resting artery diameter increased after MICT (3.68 ± 0.58 mm vs. 3.86 ± 0.58 mm, P = 0.02) but not after HIIT (4.04 ± 0.70 mm vs. 4.09 ± 0.70 mm; P = 0.63). There was a significant (P = 0.02) group × time interaction in low flow-mediated constriction (L-FMC) between MICT (0.63 ± 2.00% vs. -2.79 ± 3.20%; P = 0.03) and HIIT (-1.04 ± 4.09% vs. 1.74 ± 3.46%; P = 0.29). V̇o2 max increased (P < 0.01) similarly after HIIT (2.19 ± 0.65 l/min vs. 2.64 ± 0.88 l/min) and MICT (2.24 ± 0.48 l/min vs. 2.55 ± 0.61 l/min). Biomarkers of cardiovascular risk and endothelial function were unchanged. HIIT and MICT produced different vascular adaptations in obese adults, with HIIT improving FMD and MICT increasing resting artery diameter and enhancing L-FMC. HIIT required 27.5% less total exercise time and ∼25% less energy expenditure than MICT.

Association of endothelial proliferation with the magnitude of weight loss during calorie restriction

OBJECTIVES

Substantial weight loss through intense dietary regimens is thought to ameliorate endothelial dysfunction in obesity. It is less clear whether similar improvements can be achieved with modest dietary interventions. This study aimed to identify the parameters of endothelial cell status in obesity that are affected by mild calorie restriction.

METHODS

Human umbilical vein endothelial cells (EA.hy926 line) in culture were exposed pairwise to serum from 57 individuals with simple obesity (BMI > 30 kg/m(2)) collected before and after 8-week dietary intervention with energy deficit of 300-500 kcal/day.

RESULTS

Analysis of endothelial transcriptome suggested that the intervention could impact on endothelial cell growth. Cell proliferation was measured with the MTT test and verified by [(3)H]-thymidine incorporation. The participants were categorized according to a change in proliferation over time. Significant decrease in endothelial cell proliferation correlated with the extent of weight loss in men, but not in women. This effect corresponded with changes in serum levels of leptin and adiponectin, but was not related to serum concentrations of several known angiogenic mediators (VEGF, MCP-1, TSP-1, MMP-9, angiopoietin-2).

CONCLUSION

Direction and magnitude of changes in serum-induced endothelial cell proliferation identifies patients with the greatest weight loss in response to modest calorie restriction.

Endothelial function, folate pharmacogenomics, and neurocognition in psychotic disorders

Cardiovascular disease (CVD) is a well-described complication of schizophrenia, however, mechanisms connecting CVD with other facets of psychotic disorders, such as neurocognition, are not understood. The current study examined folate metabolism as a potential mechanism of CVD and neurocognitive deficits by: 1) using endothelial dysfunction as a biomarker of CVD, and 2) comparing enzymes associated with neurocognition, CVD, and critical to folate metabolism, methylenetetrahydrofolate reductase (MTHFR) and catechol-o-methyl transferase (COMT). Endothelial function was assessed in 147 participants with schizophrenia, schizoaffective disorder, and psychotic disorder not otherwise specified grouped by MTHFR and COMT allele status. Regression models were used to compare neurocognitive performance based on the Brief Assessment of Cognition in Schizophrenia (BACS). Overall, endothelial function predicted BACS composite z-scores after controlling for age, race, level of education, serum folate levels, and MTHFR/COMT risk allele status. Participants with at least one or more MTHFR and/or COMT risk alleles had lower BACS Composite and BACS Symbol Coding adjusted mean z-scores than those with both MTHFR CC and COMT Met/Met genotypes. Thus, endothelial dysfunction may contribute to the neurocognitive deficits seen in psychotic disorders. CVD interventions may not only reduce CVD-related morbidity, but also lessen progressive neurocognitive deficits reported in psychotic disorders.

Effects of supplementation with the fat-soluble vitamins E and D on fasting flow-mediated vasodilation in adults: a meta-analysis of randomized controlled trials

The effects of fat-soluble vitamin supplementation on cardiovascular disease (CVD) risk are not clear. Therefore, we performed a meta-analysis to quantify effects of fat-soluble vitamin supplements on fasting flow-mediated vasodilation (FMD) of the brachial artery, a validated marker to assess CVD risk. Randomized placebo-controlled trials (RCTs) were identified by a systematic search till July 2014. Seven RCTs studying the effects of vitamin E supplements (range: 300 to 1800 IU per day) and nine RCTs examining the effects of vitamin D supplements, that involved, respectively, 303 and 658 adults, were included. No studies with carotenoid or vitamin K supplements were found. Vitamin E supplementation increased FMD vs. control by 2.42% (95% CI: 0.46% to 4.37%; p = 0.015). No effects of vitamin D supplementation were found (0.15%; 95% CI: −0.21% to 0.51%; p = 0.41). These effects did not depend on subject characteristics, treatment characteristics or technical aspects of the FMD measurement. However, no dose-response relationship was evident for vitamin E, statistical significance depended on one study, while the levels of supplement were far above recommended intakes. The current meta-analysis, therefore, does not provide unambiguous evidence to support the use of fat-soluble vitamin supplements to improve fasting FMD in adults.