Strategies to reduce oxidative stress in cardiovascular disease

Abstract

A multitude of studies in experimental animals, together with clinical data, provide evidence that increased production of ROS (reactive oxygen species) are involved in the development and progression of cardiovascular disease. As ROS appear to have a critical role in atherosclerosis, there has been considerable interest in identifying the enzyme systems involved and in developing strategies to reduce oxidative stress. Prospective clinical trials with vitamins and hormone replacement therapy have not fulfilled earlier promises, although there is still interest in other dietary supplements. Superoxide dismutase mimetics, thiols, xanthine oxidase and NAD(P)H oxidase inhibitors are currently receiving much interest, while animal studies using gene therapy show promise, but are still at an early stage. Of the drugs in common clinical use, there is evidence that ACE (angiotensin-converting enzyme) inhibitors and AT1 (angiotensin II type 1) receptor blockers have beneficial effects on oxidative stress above their antihypertensive properties, whereas statins, in addition to improving lipid profiles, may also lower oxidative stress.

Ascorbic acid improves the intrahepatic endothelial dysfunction of patients with cirrhosis and portal hypertension

“…Our study confirms that patients with cirrhosis, similar to what occurs in patients with other chronic diseases with enhanced oxidative stress, 42 have reduced defensive mechanisms against oxidative stress, as indicated by the significant reduced levels of ascorbic acid and the increased levels of MDA, an index of lipid peroxidation. More importantly, the current study shows that the acute administration of high doses of the antioxidant ascorbic acid effectively attenuates the postprandial increase in portal pressure without causing any adverse effect.…”

“…Under physiological conditions, endogenous antioxidant defenses minimize this interaction and maintain a balance between ROS and NO. However, this balance may be altered in a variety of disorders that show increased oxidative stress, such as hypertension, diabetes, hypercholesterolemia, and coronary heart disease, 42 leading to an impaired endothelium-dependent vascular relaxation. In these vascular disorders, the acute administration of the antioxidant ascorbic acid has proved effective at reverting endothelial dysfunction [17][18][19][20][21][22] because of its capacity for scavenging O ⅐ , which increases the bioavailability of endothelium-derived NO.…”

Mechanisms of H2O2-induced oxidative stress in endothelial cells

“…In a non-diseased cardiovascular system, O 2 ·-, NO, and other pro-oxidants and anti-oxidants are regulated. With onset of cardiovascular disease, the pro-oxidant/anti-oxidant balance is lost and pro-oxidants increase with an eventual decrease in anti-oxidant availability and antioxidant enzyme expression during chronic oxidative stress (Honing et al 1998;Hamilton et al 2004;Muller et al 2004), notably the RNS nitric oxide (NO). The oxidant imbalance is normally associated with increased O 2 ·-and decreased NO availability (Iuchi et al 2003;Zhang et al 2003).…”

The Therapeutic Potential of Pomegranate and Its Products for Prevention of Cancer

“…The effect of reactive oxygen species (ROS) and reactive nitrogen species (RNS) on human health has been studied for decades, with results indicating increasing the risk of cancer, arthritis, degenerative eye and neurological disorders, as well as general aging (Aruoma, 1998). However, the attention has turned to the effect of these free radicals on CVD and related disorders; such as atherosclerosis, hypertension, hypercholesterolemia, type 2 diabetes, and heart failure (Hamilton et al, 2004). Sumner et al (2005) investigated the effect of daily consumption of pomegranate juice for 3 months on myocardial perfusion in patients who had coronary heart disease and myocardial ischemia in a randomized, placebo-controlled, double-blind study.…”