During the last decade, there has been considerable interest in the use of plant-derived polyphenols as nutraceuticals to slow down the progression of metabolic diseases [1,2]. Aspalathus linearis (commonly known as rooibos) is a rich source of plant polyphenols with known health promoting properties. In addition to reversing ischemia/reperfusion injury in the isolated perfused rat heart , rooibos has been shown to improve both lipotoxicity and oxidative stress in diabetic individuals at risk of developing cardiovascular disease [4,5].
Furthermore, literature has indicated that polyphenols speciﬁc to rooibos may present strong ameliorative properties against diabetes mellitus and its associated complications [6–8]. Of note, aspalathin, a C-glucosyl dihydrochalcone found uniquely in rooibos, has displayed an even greater potency to prevent diabetes-induced cardiovascular complications [9–11].
For example, a fermented rooibos extract containing abundant levels of aspalathin protected primary isolated rat cardiomyocytes from experimentally induced oxidative stress and apoptosis . Moreover, recent data from our laboratory demonstrated that aspalathin was able to protect H9c2 cardiomyocytes against high glucose-induced shifts in substrate preference by decreasing fatty acid uptake and oxidation, inferring that aspalathin might act as a fatty acid oxidation modulator in the heart of the diabetic individuals. Furthermore, we demonstrated that aspalathin treatment was able to prevent mitochondrial membrane depolarization and subsequent apoptosis by reducing DNA nick formation, while increasing Bcl2/Bax ratio .