Hypertension and oxidative stress: effects of antioxidants on blood pressure, endothelial function and oxidative stress [ 2001 - 2003 ]

Research Grant

Researchers: Prof Kevin Croft (Principal investigator) ,  Prof Ian Puddey ,  Prof Jonathan Hodgson

Brief description Cardiovascular disease (CVD) is one of the most common causes of mortality in Western countries. Hypertension (raised blood pressure) is a major risk factor for CVD, and growing evidence suggests that oxidative stress contributes to raised blood pressure. Oxidative stress occurs when the body's antioxidant defences cannot prevent damage caused by free radicals (oxidants). Free radical damage may lead to impairment of blood vessel function resulting in raised blood pressure. Therefore, we will test the hypothesis that hypertension is associated with increased oxidative stress, and that dietary supplementation with water-soluble antioxidants will reduce oxidative stress, improve blood vessel function and lower blood pressure in hypertensives subjects with higher risk of CVD. To date, there is little direct evidence demonstrating that hypertension per se is associated with increased oxidative stress. Therefore, we will undertake a comparison where oxidative stress status will be assessed and compared in hypertensive subjects with and without other risk factors for cardiovascular disease and in normal healthy subjects. If oxidative stress were contributing to high blood pressure then dietary antioxidants would be expected to lower blood pressure in subjects with hypertension. Reduced oxidative stress and improved blood vessel function would also be expected with antioxidant supplementation. Results of population and intervention studies in humans suggest that vitamin C and other water-soluble antioxidants may reduce oxidative stress, improve blood vessel function and lower blood pressure. Therefore, we will study the effects of dietary supplementation with water-soluble antioxidants, including vitamin C and polyphenolic compounds (plant food-derived antioxidants) on these three main endpoints. We will also investigate whether the form in which the antioxidants are provided, tablets versus fruit juice drink, influences the effects observed.

Funding Amount $AUD 329,122.54

Funding Scheme NHMRC Project Grants

Notes Standard Project Grant