Neurodegenerative and Morpho-functional Alterations During Senescence: Positive Modulation by Lipoic Acid and Superoxide Dismutase Ocular Senescence in a Rat Model

Abstract

We have evaluated the modulation of degenerative events at the retinal and optic nerve level in a rat model system. Degeneration was ameliorated in aging rats by the combined oral administration of -lipoic acid and superoxide dismutase. Twenty four month-old rats were fed ad libitum with a diet supplemented by these two compounds. Positive control rats received a compound-free diet, while the negative control group consisted of untreated young animals. The cyto-protective effects of -lipoic acid and superoxide dismutase were investigated by morphological analysis of retinal and optic nerve head sections. The level of nuclear DNA damage was assessed by TUNEL fluorescent reaction. Lipo-peroxidation assays evaluated the oxidative stress and consequent alteration of the cell membrane function. Apoptotic phenomena were investigated by immuno-localization and Western blotting to measure the expression of caspase-3 and inducible nitric oxide synthase. The results reported in this work provide evidence that-lipoic acid and superoxide dismutase counteract the degenerative damage in aging animals, reducing the effects of oxidative stress. Keywords-lipoic Acid; Apoptosis; Oxidative Stress; Rat Model