Nutraceutical and antioxidant effects of a delphinidin-rich maqui berry extract Delphinol®: a review.

Anthocyanins represent water-soluble flavonoid species, commonly found in higher plants, the richest plant source representing berries. While all anthocyanins present with antioxidant activity, the delphinidins represent the most potent antioxidant anthocyanin species owed to largest number of hydroxyl groups in the B-ring. The richest known natural source of delphinidins is the maqui berry (Aristotelia chilensis) from which an extract Delphinol®, standardized to 25% delphinidin, is commercially available. Delphinol® significantly reduces oxidative stress (oxidized LDL and F2-isoprostane) and blood glucose in controlled clinical trials. In human umbilical vein endothelium delphinidins concentration-dependently decrease intracellular oxygen radicals. Furthermore, delphinidins increase endothelial nitric oxide synthase expression and decreases expression of vaso-constrictory endothelin-1. Delphinidins inhibit the expression of cell adhesion molecules ICAM and VCAM, thus counteracting vascular inflammatory situations. Furthermore, delphinidins decrease platelet activity and may contribute to thrombosis prevention. Research on delphinidins showed improved endothelial function with elevated endothelial NO generation, lowered platelet aggregability and anti-inflammatory vascular effects. Delphinidins dose-dependently inhibit NF-κB-, activator protein-1- as well as COX-2 expression in UV-exposed epidermis. Delphinidins are found to be internalized into keratinocytes and pre-clinical investigations show significant UV-photo-protective 1effects with topical application of 40 nM delphinidin, both when applied prior to UV exposure as well as after exposure. Delphinidins may counteract skin-aging due to inhibition of UV-induced expression of matrix metalloproteinase in fibroblasts. In a rodent osteoporosis model delphinidin was found to inhibit differentiation of osteoclasts, resulting in an inhibited bone demineralization, while other anthocyanins were ineffective. Future research on Delphinol® and delphinidins may be expected to identify further health benefits.