In vitro antioxidant synergism and antagonism between food extracts can lead to similar activities in H2O2-induced cell death, caspase-3 and MMP-2 activities in H9c2 cells

BACKGROUND: The cardio‐health‐promoting activity of some foods may be due to their specific antioxidant content. The antioxidant activity of a mixture of plant extracts has been shown to differ from the activity of the individual extracts. As a result, the activity of the mixture can be described as synergistic, antagonistic or additive. This in vitro study evaluated the relationship between the in vitro antioxidant capacity of mixtures and their bioactivity when cardiomyocytes (H9c2) were challenged with H2O2. RESULTS: A mixture of raspberry and adzuki bean extracts produced a synergistic response and a mixture of broccoli and soybean extracts produced an antagonistic response in chemical‐based antioxidant assays. When these extracts were tested in cell cultures, individually and in mixtures, the mixture of raspberry and adzuki bean protected the cardiomyocytes from H2O2‐induced cell damage significantly better than the individual extracts. Conversely, the mixture of broccoli and soybean extracts was less effective in protecting H9c2 cells. The synergistic and antagonistic effects of the mixtures in protecting cell damage were brought about by enhanced or reduced ability in attenuating caspase‐3 and matrix metalloproteinase‐2 activities elevated by H2O2. CONCLUSION: Food mixtures with synergistic antioxidant activity and protective property against reactive oxygen species‐induced cell death can potentially be incorporated into novel functional foods or beverages with optimum health benefit. The antagonistic effect of food mixtures can be a health concern and thus should be avoided. Copyright © 2012 Society of Chemical Industry