Lingonberry anthocyanins protect cardiac cells from oxidative-stress-induced apoptosis

Citation

Isaak, C.K., Petkau, J.C., Blewett, H., Karmin, O., Siow, Y.L. (2017). Lingonberry anthocyanins protect cardiac cells from oxidative-stress-induced apoptosis. Canadian Journal of Physiology and Pharmacology, [online] 95(8), 904-910. http://dx.doi.org/10.1139/cjpp-2016-0667

Plain language summary

Lingonberry grown in Northern Manitoba, Canada contains exceptionally high levels of antioxidants called anthocyanins and other polyphenols. Previous studies from our lab have shown that lingonberry anthocyanins can protect heart cells from nutrient- and oxygen-deprived cell death. As anthocyanin-rich diets have been shown to be associated with decreased cardiovascular disease and mortality, this study used hydrogen peroxide to trigger heart cell death in a dish to see if the anthocyanins from ligonberries can protect them from dying. Using a combination of techniques to detect cells at different stages of death, researchers found that low doses of the three major anthocyanins found in lingonberry (cyanidin-3-galactoside, cyandin-3-glucoside and cyanidin-3-arabinoside), and a combination of these three compounds protected the heart cells from dying. A dose-dependent protective effect (more lingonberry lead to more protection) was also demonstrated with a lingonberry extract. The results of this study are especially novel because the dosages used are within the reported amounts found in blood when people eat berries indicating that lingonberry anthocyanins may be able to protect the heart when added to the diet.

Abstract

Lingonberry grown in northern Manitoba, Canada, contains exceptionally high levels of anthocyanins and other polyphenols. Previous studies from our lab have shown that lingonberry anthocyanins can protect H9c2 cells from ischemia-reperfusion injury and anthocyanin-rich diets have been shown to be associated with decreased cardiovascular disease and mortality. Oxidative stress can impair function and trigger apoptosis in cardiomyocytes. This study investigated the protective effects of physiologically relevant doses of lingonberry extracts and pure anthocyanins against hydrogen-peroxideinduced cell death. Apoptosis and necrosis were detected in H9c2 cells after hydrogen peroxide treatment via flow cytometry using FLICA 660 caspase 3/7 combined with YO-PRO-1 and then confirmed with Hoechst staining and fluorescence microscopy. Each of the 3 major anthocyanins found in lingonberry (cyanidin-3-galactoside, cyanidin-3-glucoside, and cyanidin-3-arabinoside) was protective against hydrogen-peroxide-induced apoptosis in H9c2 cells at 10 ng·mL−1 (20 nmol·L−1) and restored the number of viable cells to match the control group. A combination of the 3 anthocyanins was also protective and a lingonberry extract tested at 3 concentrations produced a dose-dependent protective effect. Lingonberry anthocyanins protected cardiac cells from oxidative-stress-induced apoptosis and may have cardioprotective effects as a dietary modification.

Publication date

2017-01-01