Anthocyanins are red to blue pigmented antioxidants found in a range of fruits and vegetables as well as some other plants for which heart health and even cancer-reduction scientific backing is mounting.
The researchers claimed their study was the first using animals to test the heart health benefits of anthocyanins.
"To date, there has been very little research conducted specifically investigating the causal impact of anthocyanin consumption on risk of cardiovascular disease in animal models," the French researchers said.
In the study one group of rats was fed an anthocyanin-rich, maize-based diet while the other was fed an anthocyanin-free diet over eight weeks.
The dietary intake was otherwise similar in energy, protein, lipid, and micronutrients.
The researchers observed that " naturally-occurring anthocyanins found in this maize-based diet were readily absorbed by the animals."
Heart benefits In both in vivo and ex vivo studies, consumption of an anthocyanin-rich diet significantly reduced the amount of cardiac tissue that was damaged following ischemic (lack of blood flow) conditions by approximately 30 per cent.
"Both total and reduced glutathione concentrations in heart tissue were greater in animals consuming an anthocyanin-rich diet compared to those consuming an anthocyanin-free diet," they wrote.
"These findings suggest an important potential health benefit of consuming foods rich in anthocyanins - at least in rats.
Controlled, clinical intervention trials are warranted to determine if anthocyanin consumption in humans also has cardio-protective effects."
The method involved scrutinising the heart tissues' response to ischemia in two experimental models: the hearts of living animals ( in vivo ) and hearts freshly removed from the body ( ex vivo ).
The researchers also analysed the heart muscles' content of reduced and oxidised forms of glutathione, a protein important in protecting the body from oxidative (free radical) damage.
While there is much epidemiologic evidence linking fruit and vegetable consumption with decreased risk of several chronic diseases such as cardiovascular disease and cancer, less is known about just which components are responsible for this positive effect.
It is thought anthocyanins have the greatest antioxidant activity, potentially protecting the heart muscle from free radical damage.
Source: Journal of Nutrition April 2008 Volume 139.
Pages 747-752.
Chronic dietary intake of plant-derived anthocyanins protects the rat heart against ischemia-reperfusion injury.
Authors : Toufektsian M-C, de Lorgeril M, Nagy N, et al.