Sulforaphane and Vitamin E Protect From Glucotoxic Neurodegeneration and Lifespan Reduction In C. Elegans

Caenorhabditis elegans is an established model organism in neurodegeneration and aging research. Oxidative stress and formation of advanced glycation endproducts (AGEs), as they occur under hyperglycemic conditions in diabetes mellitus, contribute to neuronal damage and lifespan reduction. Sulforaphane (SFN) is an indirect antioxidant, alpha-tocopherol (vitamin E) is a direct antioxidant that acts as a free radical scavenger. Aim of this study is to investigate the protective effects of SFN and vitamin E against glucotoxic damages to the neuronal system and lifespan in C. elegans. Culture conditions that mimic clinical hyperglycemia increased the formation of reactive oxygen species (ROS) (p<0.001) and the accumulation of methylglyoxal-derived advanced glycation endproducts (MG-derived AGEs) (p<0.01) with subsequent neuronal damage and neuronal dysfunction, ultimately leading to a significant shortening of lifespan (p<0.01). Treatment with both, 20 µmol/l SFN and 200 µg/ml vitamin E, completely prevented the increase in ROS and MG-derived AGEs, abolished the glucotoxic effects on neuronal structure and function, and preserved lifespan, resulting in a life expectancy similar to untreated controls. These data emphasize the relevance of indirect and direct antioxidants as potential therapeutic options for the prevention of glucotoxic pathologies.