A polyphenols-rich diet keeps the heart younger, according to a study by the FLORA Project, a European Commission funded research studying the effects of flavonoids, a variety of polyphenols, on human health.

"The biological and protective activities of various flavonoids have been extensively studied in vitro, on cell- based assays," says Marie-Claire Toufektsian, leading author of the study. "Nevertheless, this kind of approach has a major limitation: it is extremely difficult to assess precisely the nature of all flavonoids absorbed following consumption of plants present in a given meal. In other words, laboratory cultured cells alone are not sufficient to study a complex mechanism such as that of absorption of food flavonoids. That is why we need to turn attention on other features. The most obvious solution appeared to be to study the effects of this kind of polyphenols on experimental animals. The turning point started from plants: those rich in flavonoids made the case of researchers."

The study used two kinds of corn: one anthocyanin-free (anthocyanins is a variety of flavonoids) and the other, obtained by the Department of Biomolecular Sciences and Biotechnology of University of Milan through traditional cultivation techniques with no transgenic modifications, rich in anthocyanins.

“The corn seeds were introduced into a rodent food formula in order to obtain two groups of rats following two different kinds of diet for a couple of months,” says Chiara Tonelli, head of the Milan group. The researchers accurately measured the anthocyanins levels in urine and plasma samples from the two groups of rats by using a method developed by the Research Laboratories at the Catholic University of Campobasso. Then researchers studied the onset and evolution of myocardial infarction induced experimentally in both groups.

“We found," Toufektsian adds, "that chronic consumption and effective absorption of anthocyanins rendered the rats more resistant to myocardial infarction; in other words, the size of the infarct was significantly reduced in rats fed the anthocyanin-rich diet”.

The quantity of absorbed anthocyanins is important too. Maria Benedetta Donati, scientific coordinator of the Research Laboratories of Campobasso, argues that “the rats fed the anthocyanin- rich diet received about 13- fold more anthocyanins than most people following a standard Western-type diet, where the daily consumption of flavonoids is relatively low and the average intake of anthocyanins is estimated to be only 12 mg per day.”

The authors stressed the difference between this kind of Mediterranean diet and the so-called Western Diet, which is commonly considered richer in fats and poor in fiber. “The anthocyanins content of the traditional Mediterranean diet is much higher than that of the Western Diet, which might explain why the Mediterranean diet is cardioprotective” says Michel de Lorgeril, cardiologist, head of the Grenoble group.

However promising these results appear to be, the researchers urge caution. "The cellular mechanisms of the protection are not clearly determined yet," says Toufektsian, "Moreover, there may be differences between humans and rats, for example in terms of flavonoid absorption and metabolism."

Human volunteers are the target of another phase of the FLORA Project. The Research Laboratories of the Catholic University of Campobasso are studying the process of absorption and metabolism of anthocyanins from blood orange juice- one of the most generous sources of flavonoids- in human body. In this way researchers aim at evaluating how these compounds are absorbed by human body to play their beneficial effects.

The FLORA Project

Funded by the European Commission within the 6th framework program, the FLORA Project aims at gaining further evidence on the dynamics triggered by flavonoids, establishing a forefront in Europe for the study of association among these compounds and cardiovascular disease, myocardial infarction and tumours. FLORA researchers are involved in the field of flavonoids contained in different vegetables, such as corn, tomatoes and an experimental plant called Arabidopsis. Oranges too are other protagonists of this study. They are rich in flavonoids and phenolics by their own nature. FLORA’s oranges have something more: the amount of antioxidant has been enriched in order to optimize their natural beneficial effects. Moreover, these fruits are additive free and have been cultivated in full respect of healthy parameters. There is no risk of unexpected surprises but just a measured increase in terms of nutrition. Promoting health through a balanced and correct diet, in respect for different food tradition of European Countries, is the mission of FLORA.

Research Centres from different European Countries participate to the Project.

FLORA Project partners:

John Innes Centre, Norwich, United Kingdom
Università degli Studi di Milano, Italy
Institute of Plant Genetics and Crop Plant Research, Gatersleben, Germany
Research Laboratories, Catholic University, Campobasso, Italy
Plant Research International, Wageningen, The Netherlands
TIMC-IMAG, PRETA Coeur & Nutrition, CNRS UMR 5525- UJF- INP, Faculté de Médicine, Université de Grenoble
Istanbul Technical University, Turkey
Congenia SRL, Italy
Istituto Sperimentale per l’Agrumicoltura, Italy
Ortogel, Italy
Biopolo SRL, Italy

Article: M. Toufektsian, M. de Lorgeril, N. Nagy, P. Salen, M. Donati, L. Giordano, H. Mock, S. Peterek, A. Matros, K. Petroni, R. Pilu, D. Rotilio, C. Tonelli, J. de Leiris, F. Boucher, and C. Martin, "Chronic Dietary Intake of Plant-Derived Anthocyanins Protects the Rat Heart against Ischemia-Reperfusion Injury", The Journal of Nutrition, April 2008 Volume 138 Number 4