Nutraceuticals, aging, and cognitive dysfunction.

Decline in cognitive function that accompanies aging in dogs might have a biological basis, and many of the disorders associated with aging in canines might be preventable through dietary modifications that incorporate specific nutraceuticals. Based on previous research and the results of laboratory and clinical studies, antioxidants might be one class of nutraceutical that benefits aged dogs. Brains of aged dogs accumulate oxidative damage to proteins and lipids, which can lead to dysfunction of neuronal cells. The production of free radicals and lack of increase in compensatory antioxidant enzymes might lead to detrimental modifications to important macromolecules within neurons. Reducing oxidative damage through food ingredients rich in a broad spectrum of antioxidants significantly improves, or slows the decline of, learning and memory in aged dogs; however, determining which compounds, combinations, dosage ranges, when to initiate intervention, and long-term effects constitute critical gaps in knowledge about this subject.