Combined effects of aging and a pro‐diabetic diet on retinal function in a murine model of aging of the human eye

Abstract

Abstract Purpose Improvement of life expectancy and changes in the dietary behaviour of developed populations are accompanied with the prevalence of diabetes and age‐related ocular pathologies. Aging of the retina is characterized by accumulation of lipids at its basement. Meanwhile increased oxidative stress is one of the features of aging and diabetes. The goal of our study was to evaluate the effects of a pro‐diabetic fructose‐rich diet on the functioning of the retina in a murine model of aging of the human eye, the ApoB100,LDLR‐/‐ mice. Methods 4 month‐old ApoB100,LDLR‐/‐ and SF2J control mice were bred under either a standard chow or a fructose‐rich diet (60%) during 6 months (n=6 in each group). The functionality of the retina was further evaluated by single flash electroretinography (ERG) under scotopic conditions to assess the global response of the retina. Flicker ERG was monitored by increasing flash intensity upon 10Hz‐fixed frequency of the stimulus to specifically assess the sensitivity of rods and cones. Results The fructose‐rich diet significantly decreased a‐ and b‐wave amplitudes of the retina to single flash ERG. This diminution was intensified in ApoB100, LDLR‐/‐ mice compared to control mice: ‐55.5% vs ‐33.4% for the a‐wave, ‐41% vs ‐38% for b‐wave, respectively. The fructose‐enriched diet impaired the sensitivity of rods by 0.3 log unit in both strains of mice. Conclusion Oxidative stress triggered by a pro‐diabetic diet promotes the deleterious effects of aging on the retina by reducing its functionality and impairing its sensitivity to light stimulus.