Nattokinase for Prevention of Atherosclerosis Progression (NAPS Trial)

The potential for nattokinase to "thin" blood and to reduce blood clotting by positive antithrombotic and fibrinolytic effects presents a unique opportunity to safely study such effects on cardiovascular disease and cognition. Unfortunately, such studies of antithrombotic and fibrinolytic pathways of prevention have been limited due to lack of safe compounds and the adverse reactions associated with current agents such as Coumadin. Nattokinase, an over-the-counter supplement used for cardiovascular health, is the most active functional constituent of natto, a fermented soy product. Natto has been consumed primarily by the Japanese for over 1000 years, a population with one of the lowest risks for cardiovascular disease and dementia. Cardiovascular disease and dementia remain the most challenging age-related health risks of the 21st century for Americans necessitating development of further effective preemptive strategies. Whether reducing the propensity for thrombus formation and/or increasing fibrinolytic activity can prevent the progression of atherosclerosis and cognitive decline has not yet been determined. Using nattokinase under primary prevention conditions, the investigators propose to conduct a randomized, double-blinded, placebo-controlled trial to determine whether decreasing atherothrombotic risk can reduce the progression of subclinical atherosclerosis and cognitive decline. The investigators propose to randomize 240 healthy non-demented women and men to nattokinase supplementation or to placebo for three years. The primary trial endpoints will be measurement of carotid arterial wall thickness and arterial stiffness, early changes of atherosclerosis that can be measured safely by non-invasive imaging techniques. The secondary trial endpoint will be ascertained through change in cognition measured by a neuropsychological battery. In addition, biochemical blood measurements and in vitro studies will be conducted to compare the effects of nattokinase relative to placebo on blood coagulation and thrombus break-down capabilities, blood flow properties, inflammation and inflammatory activation of endothelial cells that line blood vessels.