Blackcurrant anthocyanins improve visual contrast resolution for optokinetic responses in aging mice

Visual motion perception declines during natural aging in most animals including humans. Edible berries of blackcurrant (BC) and its extracted anthocyanins (BCAs) have beneficial effects on human eyes. However, the effect of BCAs on the perception of moving objects and other dynamic visual patterns remains unknown. In the current study, we investigated whether BCAs improve visual movement perception in aging mice. The aging mice were fed either a standard diet or a standard diet containing BC. In addition, BCAs, the major component of BC, was orally administered to aging mice. The optokinetic responses (OKR) to the vertical sinusoidal patterns were then compared between the groups. To assess the transcriptional effects of delphinidin 3-O-β-rutinoside (D3R), a major BCA, we performed RNA-seq analysis using total RNA purified from the retina and V1 of control and D3R-administered aging mice. Larger OKRs were observed in BC-fed mice than in control mice at low grating contrast, suggesting that the contrast resolution to track moving patterns was improved. Similar results were observed in mice orally administered BCAs. Furthermore, we examined the effects of BCAs on the aging mouse retina and the primary visual cortex (V1) at the gene expression level. RNA-seq analysis of BCA-administered aging mouse retinas and V1s indicated activation of genes related to neural protection and neuronal survival, including BDNF and EGF. Taken together, the current study suggests that BCA ingestion alleviates the decline in contrast-dependent moving visual function in aging mice, accompanied by transcriptional profile change of the V1 and retina.