Exercise and the aging endothelium

Alcohol drinking triggered decrease of oxidative balance score is associated with high all-cause and cardiovascular mortality in hypertensive individuals: findings from NHANES 1999-2014

BACKGROUND

Oxidative stress is closely associated with hypertensive outcomes. The oxidative balance score (OBS) measures oxidative stress exposure from dietary and lifestyle elements. The objective of this study was to investigate the association between OBS and mortality in hypertensive patients.

METHODS

This study included 7823 hypertensive patients from the National Health and Nutrition Examination Survey (NHANES) 1999-2014. Several models, including Cox regression, restricted cubic splines (RCS), Kaplan‒Meier survival analysis, subgroup, and sensitivity analyses, were exploited to investigate the relationship between OBS and the risk of mortality.

RESULTS

Controlling for all potential confounders, a significantly inverse association was observed between elevated OBS and all-cause [hazard ratio (HR) = 0.90, 95% CI: 0.85-0.95] and cardiovascular mortality (HR = 0.85, 95% CI: 0.75-0.95). With adjustment for covariates, significant associations between lifestyle OBS and mortality risks diminished, whereas associations between dietary OBS and these mortality risks remained robust (all-cause mortality: HR = 0.91, 95% CI: 0.86-0.96; cardiovascular mortality: HR = 0.85, 95% CI: 0.76-0.96). RCS demonstrated a linear relationship between OBS and all-cause and cardiovascular mortality risk (P nonlinear = 0.088 and P nonlinear = 0.447, respectively). Kaplan‒Meier curves demonstrated that the mortality rate was lower with a high OBS (P < 0.001). The consistency of the association was demonstrated in subgroup and sensitivity analyses. RCS after stratification showed that among current drinkers, those with higher OBS had a lower risk of mortality compared with former or never drinkers.

CONCLUSIONS

In hypertensive individuals, there was a negative association between OBS and all-cause and cardiovascular mortality. Encouraging hypertensive individuals, especially those currently drinking, to maintain high levels of OBS may be beneficial in improving their prognosis.

Vascular Aging: Assessment and Intervention

Vascular aging represents a collection of structural and functional changes in a blood vessel with advancing age, including increased stiffness, vascular wall remodeling, loss of angiogenic ability, and endothelium-dependent vasodilation dysfunction. These age-related alterations may occur earlier in those who are at risk for or have cardiovascular diseases, therefore, are defined as early or premature vascular aging. Vascular aging contributes independently to cardio-cerebral vascular diseases (CCVDs). Thus, early diagnosis and interventions targeting vascular aging are of paramount importance in the delay or prevention of CCVDs. Here, we review the direct assessment of vascular aging by examining parameters that reflect changes in structure, function, or their compliance with age including arterial wall thickness and lumen diameter, endothelium-dependent vasodilation, arterial stiffness as well as indirect assessment through pathological studies of biomarkers including endothelial progenitor cell, lymphocytic telomeres, advanced glycation end-products, and C-reactive protein. Further, we evaluate how different types of interventions including lifestyle mediation, such as caloric restriction and salt intake, and treatments for hypertension, diabetes, and hyperlipidemia affect age-related vascular changes. As a single parameter or intervention targets only a certain vascular physiological change, it is recommended to use multiple parameters to evaluate and design intervention approaches accordingly to prevent systemic vascular aging in clinical practices or population-based studies.

Investigation of the effects of swimming exercises in rats given acrylamide

BACKGROUND

Acrylamide is a toxic substance used in industrial and laboratory processes. Acrylamide exposure has a toxic effect on many systems. Protective mechanisms should be developed against the effects caused by acrylamide.

OBJECTIVE

In our study, we investigated whether exercise has a protective effect against the changes that acrylamide will cause in pancreas.

METHODS

32 adult Sprague-Dawley male rats were used. Control group was given only saline. Exercise group was applied swimming exercise for 1hour daily for 4 weeks. Acrylamide group was given 50mg/kg acrylamide by gavage for 4 weeks. Acrylamide+exercise group was applied 50mg/kg acrylamide for 4 weeks and swimming exercise for 1hour daily. After the experiment, fasting blood glucose and oral glucose tolerance test measurements were performed. Then, blood and pancreas samples were taken.

RESULTS

Acrylamide exposure caused an increase in fasting blood glucose and oral glucose tolerance, a decrease in insulin levels and oxidative stress in acrylamide group. In exercise group, these values were similar to control group and no significant change was observed in acrylamide+exercise group. While there was an increase in the number of alpha cells in acrylamide group compared to the other groups, here was a decrease in the number of beta cells compared to control group.

CONCLUSION

We can say that acrylamide causes changes in the islets of Langerhans by affecting alpha and beta cell numbers. The protective effect of exercise on beta and alpha cell mass was not statistically significant in the acrylamide+exercise group. When the results were examined, the decrease in oxidative stress and the higher number of beta and alpha cells in the acrylamide+exercise group compared to the acrylamide group suggested that 4 weeks of swimming exercise may have an effect on acrylamide exposure.

Exercise protects vascular function by countering senescent cells in older adults

Blood vessels are key conduits for the transport of blood and circulating factors. Abnormalities in blood vessels promote cardiovascular disease (CVD), which has become the most common disease as human lifespans extend. Aging itself is not pathogenic; however, the decline of physiological and biological function owing to aging has been linked to CVD. Although aging is a complex phenomenon that has not been comprehensively investigated, there is accumulating evidence that cellular senescence aggravates various pathological changes associated with aging. Emerging evidence shows that approaches that suppress or eliminate cellular senescence preserve vascular function in aging-related CVD. However, most pharmacological therapies for treating age-related CVD are inefficient. Therefore, effective approaches to treat CVD are urgently required. The benefits of exercise for the cardiovascular system have been well documented in basic research and clinical studies; however, the mechanisms and optimal frequency of exercise for promoting cardiovascular health remain unknown. Accordingly, in this review, we have discussed the changes in senescent endothelial cells (ECs) and vascular smooth muscle cells (VSMCs) that occur in the progress of CVD and the roles of physical activity in CVD prevention and treatment.

Age-Related Changes in Skeletal Muscle Oxygen Utilization

The cardiovascular and skeletal muscle systems are intrinsically interconnected, sharing the goal of delivering oxygen to metabolically active tissue. Deficiencies within those systems that affect oxygen delivery to working tissues are a hallmark of advancing age. Oxygen delivery and utilization are reflected as muscle oxygen saturation (SmO2) and are assessed using near-infrared resonance spectroscopy (NIRS). SmO2 has been observed to be reduced by ~38% at rest, ~24% during submaximal exercise, and ~59% during maximal exercise with aging (>65 y). Furthermore, aging prolongs restoration of SmO2 back to baseline by >50% after intense exercise. Regulatory factors that contribute to reduced SmO2 with age include blood flow, capillarization, endothelial cells, nitric oxide, and mitochondrial function. These mechanisms are governed by reactive oxygen species (ROS) at the cellular level. However, mishandling of ROS with age ultimately leads to alterations in structure and function of the regulatory factors tasked with maintaining SmO2. The purpose of this review is to provide an update on the current state of the literature regarding age-related effects in SmO2. Furthermore, we attempt to bridge the gap between SmO2 and associated underlying mechanisms affected by aging.

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.

Aging-Induced Impairment of Vascular Function: Mitochondrial Redox Contributions and Physiological/Clinical Implications

Significance: The vasculature responds to the respiratory needs of tissue by modulating luminal diameter through smooth muscle constriction or relaxation. Coronary perfusion, diastolic function, and coronary flow reserve are drastically reduced with aging. This loss of blood flow contributes to and exacerbates pathological processes such as angina pectoris, atherosclerosis, and coronary artery and microvascular disease. Recent Advances: Increased attention has recently been given to defining mechanisms behind aging-mediated loss of vascular function and development of therapeutic strategies to restore youthful vascular responsiveness. The ultimate goal aims at providing new avenues for symptom management, reversal of tissue damage, and preventing or delaying of aging-induced vascular damage and dysfunction in the first place. Critical Issues: Our major objective is to describe how aging-associated mitochondrial dysfunction contributes to endothelial and smooth muscle dysfunction via dysregulated reactive oxygen species production, the clinical impact of this phenomenon, and to discuss emerging therapeutic strategies. Pathological changes in regulation of mitochondrial oxidative and nitrosative balance (Section 1) and mitochondrial dynamics of fission/fusion (Section 2) have widespread effects on the mechanisms underlying the ability of the vasculature to relax, leading to hyperconstriction with aging. We will focus on flow-mediated dilation, endothelial hyperpolarizing factors (Sections 3 and 4), and adrenergic receptors (Section 5), as outlined in Figure 1. The clinical implications of these changes on major adverse cardiac events and mortality are described (Section 6). Future Directions: We discuss antioxidative therapeutic strategies currently in development to restore mitochondrial redox homeostasis and subsequently vascular function and evaluate their potential clinical impact (Section 7). Antioxid. Redox Signal. 35, 974-1015.

INERTIA: A pilot study of the impact of progressive resistance training on blood pressure control in older adults with sarcopenia

Sarcopenia, and high blood pressure are highly prevalent, preventable conditions that pose significant burden for older adults and on the healthcare system. Current prevention and treatment of high blood pressure in sarcopenia, by non-pharmacological approaches remain limited and are far from optimal. Clinical trials and mechanistic studies provide encouraging evidence of a plausible therapeutic effect of progressive resistance training (PRT) on blood pressure in younger, and pre-hypertensive and hypertensive older adults. The impact of PRT on blood pressure has not been empirically tested in older adults with sarcopenia. This pilot study aims to provide effect size confidence intervals, clinical trial and intervention feasibility data, and procedural materials for a full-scale randomized controlled trial that will determine the efficacy of PRT intervention as a therapeutic strategy for blood pressure control in older adults with sarcopenia. Participants (N = 90) will be randomized to receive exercise educational materials or the PRT intervention consisting of 24 supervised exercise sessions over 12-weeks. Follow-up assessments will occur at 12-weeks and one-year later. The primary outcome is systolic blood pressure and diastolic blood pressure, analyzed separately. Microvascular mechanisms linking muscle (perfusion, strength, function) to changes in blood pressure will be explored at baseline and 12-weeks. This study will provide new evidence for the therapeutic effect of PRT as a non-pharmacological strategy for improving blood pressure. Insights gained may also inform of the potential role of muscle strength as a novel target for blood pressure control, and future exercise prescription guidelines related to muscle strengthening in high-risk older adults.

Early Detection of Negative Smoking Impacts: Vascular Adaptation Deviation Based on Quantification of Circulated Endothelial Activation Markers

Introduction

Smoking can cause vascular damage in the form of an inflammatory reaction characterized by endothelial activation. Endothelial activation forms a pathological adaptation pattern so that it can induce the atherogenesis process. Several markers, such as E-selectin, platelet-derived micro particles (PMPs) and hematopoietic stem cell (HSC) can identify the activation of endothelial in circulating blood. Therefore, the deviation of vascular adaptation due to smoking can be detected early through the feedback mechanism between E-selectin, PMPs, and HSC.

Purpose

This study aims to analyze the initial picture of the negative impact of smoking on vascular adaptation by measuring E-selectin, PMPs, and HSC in the peripheral blood circulation. Participant criteria and methods: Peripheral blood samples (5 mL) were taken from each participant, both the smoking group (n = 30) and the non-smoker group (n = 31) to obtain peripheral blood mononuclear cells (PBMNC). PBMNC was isolated using ficoll-based gradient centrifugation. The flow cytometry assay method used to measure the E-selectin, PMPs and hematopoietic stem cells.

Results

The mean of circulating E-selectin in smokers was higher than that of non-smokers. On the other hand, the average number of PMPs and HSCs in smokers was lower than non-smokers.

Conclusion

Smoking increases the risk of accelerated vascular block formation, as indicated by an increase in the amount of circulating E-selectin. The increase in E-selectin in the blood vessels mediates the increased adhesion of PMPs in the vascular area so that the number of circulating PMPs in smokers decreases. The decrease in circulating PMPs decreases the signal of vascular repair, which is characterized by a decline in the number of HSCs.

Predicting psychological factors affecting regular physical activity in hypertensive patients: Application of health action process approach model

Aim

The aim of this study was to determine the factors affecting the behaviour of regular physical activity in patients with hypertension using the health action process approach (HAPA) model.

Design

This cross-sectional study was conducted on 176 hypertension patients, in Astaneh-e-Ashrafiyeh, Guilan, Iran, 2018-2019.

Methods

Data collection tools included demographic characteristics, medical history, the short form of International Physical Activity Questionnaire (IPAQ) and scales related to the HAPA model. The data were analysed using chi-square, independent t test, one-way ANOVA, Pearson's correlation coefficient and path analysis on AMOS, version 23.0.

Results

Action self-efficacy (β = 0.59), outcome expectancy (β = 0.20) and risk perception (β = 0.18) had a statistically significant effect on intention. Moreover, the path coefficient between intention (β = 0.35) and coping self-efficacy (β = 0.29) with physical activity was statistically significant. The results revealed that HAPA constructs were able to describe 45% of the variance in intention and 31% of the variance in physical activity behaviour.

Conclusion

The HAPA model is a useful framework for describing the factors affecting physical activity in hypertension patients.

A Critical Review of the Evidence That Metformin Is a Putative Anti-Aging Drug That Enhances Healthspan and Extends Lifespan

The numerous beneficial health outcomes associated with the use of metformin to treat patients with type 2 diabetes (T2DM), together with data from pre-clinical studies in animals including the nematode, C. elegans, and mice have prompted investigations into whether metformin has therapeutic utility as an anti-aging drug that may also extend lifespan. Indeed, clinical trials, including the MILES (Metformin In Longevity Study) and TAME (Targeting Aging with Metformin), have been designed to assess the potential benefits of metformin as an anti-aging drug. Preliminary analysis of results from MILES indicate that metformin may induce anti-aging transcriptional changes; however it remains controversial as to whether metformin is protective in those subjects free of disease. Furthermore, despite clinical use for over 60 years as an anti-diabetic drug, the cellular mechanisms by which metformin exerts either its actions remain unclear. In this review, we have critically evaluated the literature that has investigated the effects of metformin on aging, healthspan and lifespan in humans as well as other species. In preparing this review, particular attention has been placed on the strength and reproducibility of data and quality of the study protocols with respect to the pharmacokinetic and pharmacodynamic properties of metformin. We conclude that despite data in support of anti-aging benefits, the evidence that metformin increases lifespan remains controversial. However, via its ability to reduce early mortality associated with various diseases, including diabetes, cardiovascular disease, cognitive decline and cancer, metformin can improve healthspan thereby extending the period of life spent in good health. Based on the available evidence we conclude that the beneficial effects of metformin on aging and healthspan are primarily indirect via its effects on cellular metabolism and result from its anti-hyperglycemic action, enhancing insulin sensitivity, reduction of oxidative stress and protective effects on the endothelium and vascular function.

Incentivizing physical activity through activity monitoring interventions in PAD - a pilot study

Background: There is ample evidence to show that supervised exercise is efficacious and cost effective for improving claudication symptoms in patients with peripheral artery disease (PAD). Home based exercise therapy can be an effective alternative to supervised exercise however, the results of this is variable depending on the level of motivation and engagement of the patient. Patients and methods: We performed a pilot study in 41 patients to determine whether a home based exercise program with the use of an activity tracking device with personalized feedback and financial incentives can increase daily activity, improve walking and sustain engagement in the exercise regimen in patients with PAD. In this randomized pilot study, the patients in the study group were fitted with an activity monitoring device and given behavioral monitoring, motivational updates and feedback regarding their exercise program. This study group was further divided in to two groups. One half of these patients in the study group were also given financial incentives if they reached their set targets. The control group wore the device with no feedback or ability to see their number of steps walked. Results: Results showed that at the end of the 12 week period, patients in the study groups walked more compared to the controls and the financial incentive structure resulted in an additional 38-63% increase in average daily steps. Conclusions: This pilot study revealed that a home-based exercise program with activity monitoring, feedback and financial incentives resulted increased daily steps, 6-minute walking distance and overall compliance with the program in PAD patients with claudication.

Exercise restores impaired endothelium-derived hyperpolarizing factor-mediated vasodilation in aged rat aortic arteries via the TRPV4-KCa2.3 signaling complex

Background

Aging leads to structural and functional changes in the vasculature characterized by arterial endothelial dysfunction and stiffening of large elastic arteries and is a predominant risk factor for cardiovascular disease, the leading cause of morbidity and mortality in modern societies. Although exercise reduces the risk of many age-related diseases, including cardiovascular disease, the mechanisms underlying the beneficial effects of exercise on age-related endothelial function fully elucidated.

Purpose

The present study explored the effects of exercise on the impaired endothelium-derived hyperpolarizing factor (EDHF)–mediated vasodilation in aged arteries and on the involvement of the transient receptor potential vanilloid 4 (TRPV4) channel and the small-conductance calcium-activated potassium (K_Ca2.3) channel signaling in this process.

Methods

Male Sprague-Dawley rats aged 19–21 months were randomly assigned to a sedentary group or to an exercise group. Two-month-old rats were used as young controls.

Results

We found that TRPV4 and K_Ca2.3 isolated from primary cultured rat aortic endothelial cells pulled each other down in co-immunoprecipitation assays, indicating that the two channels could physically interact. Using ex vivo functional arterial tension assays, we found that EDHF-mediated relaxation induced by acetylcholine or by the TRPV4 activator GSK1016790A was markedly decreased in aged rats compared with that in young rats and was significantly inhibited by TRPV4 or K_Ca2.3 blockers in both young and aged rats. However, exercise restored both the age-related and the TRPV4-mediated and K_Ca2.3-mediated EDHF responses.

Conclusion

These results suggest an important role for the TRPV4-K_Ca2.3 signaling undergirding the beneficial effect of exercise to ameliorate age-related arterial dysfunction.

Beneficial Pleiotropic Antidepressive Effects of Cardiovascular Disease Risk Factor Interventions in the Metabolic Syndrome

BACKGROUND

Although the increased prevalence and severity of clinical depression and elevated cardiovascular disease risk represent 2 vexing public health issues, the growing awareness of their combined presentation compounds the challenge. The obese Zucker rat, a model of the metabolic syndrome, spontaneously develops significant depressive symptoms in parallel with the progression of the metabolic syndrome and, thus, represents a compelling model for study. The primary objective was to assess the impact on both cardiovascular outcomes, specifically vascular structure and function, and depressive symptoms in obese Zucker rats after aggressive treatment for cardiovascular disease risk factors with long-term exercise or targeted pharmacological interventions.

METHODS AND RESULTS

We chronically treated obese Zucker rats with clinically relevant interventions against cardiovascular disease risk factors to determine impacts on vascular outcomes and depressive symptom severity. While most of the interventions (chronic exercise, anti-hypertensive, the interventions (long-term exercise, antihypertensive, antidyslipidemia, and antidiabetic) were differentially effective at improving vascular outcomes, only those that also resulted in a significant improvement to oxidant stress, inflammation, arachidonic acid metabolism (prostacyclin versus thromboxane A2), and their associated sequelae were effective at also blunting depressive symptom severity. Using multivariable analyses, discrimination between the effectiveness of treatment groups to maintain behavioral outcomes appeared to be dependent on breaking the cycle of inflammation and oxidant stress, with the associated outcomes of improving endothelial metabolism and both cerebral and peripheral vascular structure and function.

CONCLUSIONS

This initial study provides a compelling framework from which to further interrogate the links between cardiovascular disease risk factors and depressive symptoms and suggests mechanistic links and potentially effective avenues for intervention.

Physical Activity for the Prevention of Cardiovascular Diseases

Over the last decade, the quantity and quality of scientific literature examining the relationship between physical activity (PA) and cardiovascular diseases (CVD) have significantly increased. Data from the literature now unequivocally show that physical inactivity is one of the major risk factors for CVD. It is believed that obesity, the prevalence of which has tripled over the last three decades, and physical inactivity among children are the main factors that will increase the prevalence of CVD in this century. The cardiovascular benefits of exercise are multifactorial and include important systemic effects on skeletal muscle, the peripheral vasculature, metabolism, and neurohumoral systems, as well as beneficial alterations within the myocardium itself. Thus, exercise does much more than change traditional risk factors, such as blood pressure, blood lipids, glucose tolerance and insulin resistance, metabolic syndrome, and overweight and obesity. Evidence from epidemiologic studies suggests that the preventive effects of PA may be achieved by 150 minutes of moderate PA a week, while increases in the intensity and volume of exercise lead to further health benefits. This dose–response gradient is curvilinear, with the largest gains from the first hour of weekly exercise. However, although much progress has been made in this field, existing studies performed on human subjects do not clearly show what type, intensity, and duration of exercise is most beneficial to cardiovascular fitness and metabolic optimization. Animal-based exercise studies may provide more information and help to elucidate the abilities of different training regimens to reduce the risk of CVD.

Systemic Inflammation in the Genesis of Frailty and Sarcopenia: An Overview of the Preventative and Therapeutic Role of Exercise and the Potential for Drug Treatments

The clinical, pathological and biological characteristics of frailty and sarcopenia are becoming better understood and defined, including the role of systemic inflammation. It is increasingly apparent that in older adults there is a tendency for the innate immune network to shift toward a pro-inflammatory setting, often due to the presence of chronic inflammatory diseases but also associated with age alone in some individuals. Furthermore, acute inflammation tends to resolve more slowly and less completely in many elderly people. Inflammation contributes to the pathogenesis of sarcopenia and other components of the frailty syndrome. Blood levels of inflammatory cytokines and acute phase proteins, are reduced by exercise, and there is a growing body of epidemiological, observational and intervention research that indicates that regular moderate exercise improves strength, function, morbidity and mortality in middle-aged and elderly adults. There is also an increasing awareness of the potential role of drugs to ameliorate inflammation in the context of frail old age, which might be particularly useful for people who are unable to take part in exercise programs, or as adjunctive treatment for those who can. Drugs that shift the innate immune biochemical network toward an anti-inflammatory setting, such as methyl-xanthines and 4-amino quinolones, could be of value. For example, theophylline has been shown to induce a 20 percent fall in pro-inflammatory tumor necrosis factor (TNF) and 180 percent rise in anti-inflammatory interleukin-10 production by peripheral blood monocytes, and a fall of 45 percent in interferon-gamma (IF-gamma) release. Such properties could be of therapeutic benefit, particularly to re-establish a less inflamed baseline after acute episodes such as sepsis and trauma.

The effects of resveratrol on aging vessels

Aging is a major risk factor for the development of cardiovascular disease. Despite a significant reduction in the mortality and morbidity rates over the last decade, the socio-economic burden of cardiovascular disease is still substantial. Consequently, there is a considerable need for alternative strategies, such as nutraceutical supplementation, that delay the functional vascular decline present in the elderly. Compromised autophagy and oxidative stress (OS) are considered major causes of the age-related endothelial dysfunction. OS reduces the bioavailability of nitric oxide (NO), which has been associated with hypertension, arteriosclerosis, and a reduced vasodilatory response. High levels of free radicals and the low bioavailability of NO lead to a positive feedback loop of further OS, organelle damage, poor repair, and endothelial dysfunction. Here we draw attention to the relationship between OS and autophagy in the aged vasculature. We have reviewed the published literature and provided arguments that support that treatment with resveratrol stimulates autophagy and thereby has the potential to restore oxidative balance in the endothelium, which indicates that treatment with resveratrol might have therapeutic potential to restore endothelial function in the elderly.

Non-Smoking Tobacco Affects Endothelial Function in Healthy Men in One of the Largest Health Studies Ever Performed; The Nord-Trøndelag Health Study in Norway; HUNT3

BACKGROUND

Oral tobacco (snuff) is taking a large market share in Scandinavia, especially with young users. However, long-term health effects are unknown. Small studies show association between snuff and reduced endothelial function, representing an early stage of vascular injury that often precedes manifest cardiovascular disease by several years. We therefore determined the associations between snuff and endothelial function in a large sample of healthy Norwegian men.

METHODS AND DESIGN

In the Fitness substudy of the Nord-Trøndelag Health Study (HUNT3), endothelial function was measured by flow-mediated dilation (FMD). Aerobic fitness was measured by peak oxygen uptake (VO2peak). A cross-sectional design including 1 592 self-reported healthy men compared these observations with records of present tobacco use, standard cardiovascular risk factors, and socioeconomic status, using general linear models.

RESULTS

FMD was lower in snuff users (FMD: 4.12%, 3.63, 4.61) compared to non-users (FMD: 4.52%, 4.27, 4.78) after adjustment for age (difference: -0.57%, -1.12, -0.01). After further adjustment for potential confounders, FMD still tended to be lower in snuff users than in non-users (difference: -0.53%, -1.09, 0.02). This difference was even more pronounced in the inactive snuff users (-0.83%, -1.59, -0.06) and in the low fit snuff users (-0.74%, CI -0.55, 0.079).

CONCLUSIONS

Oral tobacco is associated with a tendency towards reduced endothelial function, indicating vascular changes that precede cardiovascular disease. The strongest associations were found in men with low physical activity or reduced aerobic fitness.

Antioxidant Properties of Whole Body Periodic Acceleration (pGz)

The recognition that oxidative stress is a major component of several chronic diseases has engendered numerous trials of antioxidant therapies with minimal or no direct benefits. Nanomolar quantities of nitric oxide released into the circulation by pharmacologic stimulation of eNOS have antioxidant properties but physiologic stimulation as through increased pulsatile shear stress of the endothelium has not been assessed. The present study utilized a non-invasive technology, periodic acceleration (pGz) that increases pulsatile shear stress such that upregulation of cardiac eNOS occurs, We assessed its efficacy in normal mice and mouse models with high levels of oxidative stress, e.g. Diabetes type 1 and mdx (Duchene Muscular Dystrophy). pGz increased protein expression and upregulated eNOS in hearts. Application of pGz was associated with significantly increased expression of endogenous antioxidants (Glutathioneperoxidase-1(GPX-1), Catalase (CAT), Superoxide, Superoxide Dismutase 1(SOD1). This led to an increase of total cardiac antioxidant capacity along with an increase in the antioxidant response element transcription factor Nrf2 translocation to the nucleus. pGz decreased reactive oxygen species in both mice models of oxidative stress. Thus, pGz is a novel non-pharmacologic method to harness endogenous antioxidant capacity.

Characterization of reactive oxygen species in diaphragm

Reactive oxygen species (ROS) exist as natural mediators of metabolism to maintain cellular homeostasis. However, ROS production may significantly increase in response to environmental stressors, resulting in extensive cellular damage. Although several potential sources of increased ROS have been proposed, exact mechanisms of their generation have not been completely elucidated. This is particularly true for diaphragmatic skeletal muscle, the key muscle used for respiration. Several experimental models have focused on detection of ROS generation in rodent diaphragm tissue under stressful conditions, including hypoxia, exercise, and heat, as well as ROS formation in single myofibres. Identification methods include direct detection of ROS with confocal or fluorescent microscopy and indirect detection of ROS through end product analysis. This article explores implications of ROS generation and oxidative stress, and also evaluates potential mechanisms of cellular ROS formation in diaphragmatic skeletal muscle.

Whole body vibration exercises and the improvement of the flexibility in patient with metabolic syndrome

Vibrations produced in oscillating/vibratory platform generate whole body vibration (WBV) exercises, which are important in sports, as well as in treating diseases, promoting rehabilitation, and improving the quality of life. WBV exercises relevantly increase the muscle strength, muscle power, and the bone mineral density, as well as improving the postural control, the balance, and the gait. An important number of publications are found in the PubMed database with the keyword “flexibility” and eight of the analyzed papers involving WBV and flexibility reached a level of evidence II. The biggest distance between the third finger of the hand to the floor (DBTFF) of a patient with metabolic syndrome (MS) was found before the first session and was considered to be 100%. The percentages to the other measurements in the different sessions were determined to be related to the 100%. It is possible to see an immediate improvement after each session with a decrease of the %DBTFF. As the presence of MS is associated with poorer physical performance, a simple and safe protocol using WBV exercises promoted an improvement of the flexibility in a patient with MS.

The effects of aging on the functional and structural properties of the rat basilar artery

Aging leads to progressive pathophysiological changes in blood vessels of the brain and periphery. The aim of this study was to evaluate the effects of aging on cerebral vascular function and structure. Basilar arteries were isolated from male Fischer 344 cross Brown Norway (F344xBN) rats at 3, 8, and 24 months of age. The basilar arteries were cannulated in the pressurized system (90 cm H₂O). Contractile responses to KCl (30–120 mmol/L) and endothelin‐1 (10⁻¹¹–10⁻⁷ mol/L) were evaluated. Responses to acetylcholine (ACh) (10⁻¹⁰–10⁻⁴ mol/L), diethylamine (DEA)‐NONO‐ate (10⁻¹⁰–10⁻⁴ mol/L), and papaverin (10⁻¹⁰–10⁻⁴ mol/L) were assessed to determine both endothelium‐dependent and endothelium‐independent responsiveness. Advanced aging (24 months) decreased responses of the basilar artery to both the contractile and relaxing agents; whereas, DEA‐induced dilation was significantly higher in the 8‐month‐old group compared with the younger and older groups. The arterial wall‐to‐lumen ratio was significantly increased in 24‐month‐old rats. Smooth muscle cell count was also decreased in old rats. These findings indicate that aging produces dysfunction of both the endothelium and the vascular smooth muscle in the basilar artery. Aging also alters wall structure of the basilar artery, possibly through decreases in smooth muscle cell number and concomitant hypertrophy.

The purpose of this study was to determine the effects of advancing age on the structure and vasomotor responses of the basilar artery as well as the serum antioxidant capacity. Advanced aging (24 months) decreased responses of the basilar artery to both the contractile and relaxing agents, whereas, DEA‐induced dilation was significantly higher in the 8‐month‐old group compared with the younger and older rats. The arterial wall‐to‐lumen ratio was significantly increased in 24‐month‐old rats. Smooth muscle cell count was also decreased in old rats. Our findings demonstrate that aging is associated with functional impairment in endothelium‐dependent and ‐independent relaxation responses and contractility in the basilar arteries, and these diminished responses are accompanied by structural remodeling and decreased antioxidant capacity of the serum.