Purchase this article with an account.
Sally Yacout, Elizabeth R Gaillard; Examining the Role of Anthocyanins as an Antioxidant: Potential Filtering Effects and Modifications to A2E. Invest. Ophthalmol. Vis. Sci. 2015;56(7 ):2387.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Previous studies on the protective effects of the anthocyanins delphinidin galactoside and cyanidin galactoside on blue light irradiated RPE cells indicated diminished light induced damage due to the antioxidant properties of delphinidin galactoside and cyanidin galactoside. However, it was not clear if the effects were due to antioxidant behavior (chemical) or light filtering (physical) effects. In addition the doses of delphinidin galactoside and cyanidin galactoside used were non-physiological. This study distinguishes between the filtering and anti-oxidative potential of anthocyanins malvidin-3-O-glucoside (oenin) and pelargonidin-3-O-glucoside (callistephin) at physiologically relevant concentrations in solution and aims to assign structures to generated chemical product species.
Equal concentrations of A2E and anthocyanin were subjected to blue light irradiation for 30 minutes, or A2E only was irradiated for 30 minutes with subsequent addition of anthocyanin. Electrospray ionization mass spectrometry (ESI-MS) and tandem mass spectrometry (MS/MS) were used to analyze organic soluble species. An optical filter transmitting light between 570 and 640 nanometers is placed over irradiated solution as a control.
Irradiation of A2E and callistephin together resulted in negligible A2E photo-oxidation. A2E oxidation products were not observed with the subsequent addition of callistephin to irradiated A2E. A decrease in oxidized A2E was observed after the addition of oenin to irradiated A2E. These reactions generated a species with m/z 304, which was only present with anthocyanin. MS/MS of the 304 peak yields a fragmentation pattern of m/z peaks 212 and 91.
The addition of callistephin and oenin to irradiated A2E results in a substantial decrease in A2E photo-oxidation products, indicating antioxidant behavior of these anthocyanins. The observed m/z 304 is unique to the anthocyanin-A2E reaction and this species’ structure can be used to elucidate the interaction between anthocyanins and A2E in addition to structural modifications to A2E.
This PDF is available to Subscribers Only