Carnosine is a dipeptide found in high concentrations in brain and muscle tissues. A potent inhibitor of damage to proteins from sugar (glycation) and scavenger of free radicals, carnosine has been shown to reverse cellular senescence in culture. Preliminary evidence suggests that it may provide support conditions of sub-optimal brain homocarnosine metabolism leading to impairment in social interaction, communication, stereotyped behavior, and symbolic or imaginative interaction.