Exercise, nutrition and chronic diseases

Author: Christian K. Roberts

Currently, modern chronic diseases, including cardiovascular diseases, Type 2 diabetes, metabolic syndrome, and cancer, are the leading killers in Westernized society and are increasing rampantly in developing nations. In fact, obesity, diabetes, and hypertension are now even commonplace in children. Clearly, however, there is a solution to this epidemic of metabolic disease that is inundating today’s societies worldwide: exercise and diet. Overwhelming evidence from a variety of sources, including epidemiological, prospective cohort, and intervention studies, links most chronic diseases seen in the world today to physical inactivity and inappropriate diet consumption. The purpose of this review is to 1) discuss the effects of exercise and diet in the prevention of chronic disease, 2) highlight the effects of lifestyle modification for both mitigating disease progression and reversing existing disease, and 3) suggest potential mechanisms for beneficial effects.

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The consumption of polyphenols and CVD: effects on endothelial and platelet function

Author: Joseph A. Vita

Epidemiologic studies suggest that higher polyphenol intake from fruits and vegetables is associated with decreased risk for cardiovascular disease. The mechanisms explaining this observation remain unclear. This review summarizes data suggesting that flavonoids improve endothelial function and inhibit platelet aggregation in humans. The vascular endothelium is a critical regulator of vascular homeostasis, and endothelial dysfunction contributes to the pathogenesis and clinical expression of coronary artery disease. Platelet aggregation is a central mechanism in the pathogenesis of acute coronary syndromes, including myocardial infarction and unstable angina. For these reasons, the observed effects of flavonoids on endothelial and platelet function might explain, in part, the observed beneficial effects of flavonoids on cardiovascular disease risk.

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Intake of flavonoids and cardiovascular development: effects on endothelial function

Author: Joseph A. Vita

Epidemiological studies suggest that tea consumption is associated with reduced cardiovascular disease risk, but the mechanisms for these observations have remained uncertain. In recent years, it has become apparent that the endothelium plays a central role in the regulation of vascular homeostasis and that endothelial dysfunction contributes to the pathogenesis and clinical expression of cardiovascular disease. This article reviews the evidence that human tea consumption has a beneficial effect on the vascular endothelium and the clinical implications of these findings.

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The effect of exercise on endothelial function

Author: Daniel J. Green

Vascular endothelial function is essential for maintenance of health of the vessel wall and for vasomotor control in both conduit and resistance vessels. These functions are due to the production of numerous autacoids, of which nitric oxide (NO) fas been the most widely studied. Exercise training has been shown, in many animal and human studies, to augment endothelial, NO-dependent vasodilatation in both large and small vessels. The extent of the improvement in humans depends upon the muscle mass subjected to training; with forearm exercise, changes are restricted to the forearm vessels while lower body training can induce generalized benefit.

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Pulse pressure and arterial stiffness in rats - a comparison with man

Author: Michael E Safar

THE DEVELOPMENT of appropriate animal models for investigating human hypertension has been extremely valuable for studies of the natural history and the pathophysiological mechanisms of the disease. It has been considered that there is a strong similarity between spontaneously hypertensive rats (SHR) and patients with essential hypertension. Both have their apparent onsets of the condition very early in life, a reflection of their genetic backgrounds. The arterial hypertension involves a progressive increase of vascular resistance that initiates profound cardiac and systemic vascular adaptations and produces parallel increases of systolic (S), diastolic (D), and mean (M) arterial blood pressure (BP). Neural mechanisms seem to predominate in the early stages of both species’ hypertensive diseases (especially in SHR), although in rats, multiple structural and functional disorders seem to be involved.

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The use of peripheral pulse wave analysis in the clinic

Author: Christopher S Hayward

Nitric oxide (NO) is recognized to be a potent smooth muscle relaxant responsible, in large part, for vasodilation in response to stimulation of an intact endothelium. The obligatory role of the endothelium in vasodilation offers a mechanism whereby arterial “health” can be assessed prior to the development of atheroma. Studies have confirmed that endothelial dysfunction occurs prior to atheroma formation, and assessment of endothelial function has been used as a surrogate marker for arterial damage. Although these studies have examined endothelial function in the brachial artery (by ultrasound measurement of brachial artery flow-mediated dilation in response to reactive hyperemia), fundamental to the significance of the technique is the close relationship demonstrated between peripheral endothelial dysfunction and coronary atheroma.

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Non-invasive assessment of endothelial function: the choice method

Author: Ann E Donald

The vascular endothelium is a key signal transducer in atherogenesis. Study of preclinical vascular disease has been facilitated by use of non-invasive ultrasound techniques. The vasodilator response to increased conduit arterial flow (flow-mediated dilation [FMD]) is dependent on local nitric oxide (NO) bioavailability, and measurement of this response has been widely used in clinical studies. Recently, alternative non-invasive techniques have been developed with beta2 adrenoceptor agonist-mediated endothelial NO release, using measurement of the response with radial artery applanation tonometry (pulse wave analysis [PWA]) or digital photoplethysmography (pulse contour analysis [PCA]). Although the equipment is small, portable, and easy to use, the comparative reproducibility of PWA and PCA and their ability to detect acute vascular changes have not been determined. We designed this study to assess the reproducibility of PWA, PCA, and FMD in children and adults and compared their ability to detect inflammation-induced changes in vascular function.

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contour analysis of pulse wave volume

Author: Sandrine C. Milasseau

Analysis of the contour of the peripheral pulse to assess arterial properties was first described in the nineteenth century. With the recognition of the importance of arterial stiffness there has been a resurgence of interest in pulse wave analysis, particularly the analysis of the radial pressure pulse acquired using a tonometer. An alternative technique utilizes a volume pulse. This may conveniently be acquired optically from a finger (digital volume pulse). Although less widely used, this technique deserves further consideration because of its simplicity and ease of use. As with the pressure pulse, the contour of the digital volume pulse is sensitive to changes in arterial tone induced by vasoactive drugs and is influenced by ageing and large artery stiffness. Measurements taken directly from the digital volume pulse or from its second derivative can be used to assess these properties. This review describes the background to digital volume pulse contour analysis, how the technique relates to contour analysis of the pressure pulse, and current and future applications.

J Hypertens 24:1449–1456 Q 2006 Lippincott Williams & Wilkins.

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