Olfactory dysfunction and cognitive impairment in age-related neurodegeneration: prevalence related to patient selection, diagnostic criteria and therapeutic treatment of aged clients receiving clinical neurology and community-based care

Abstract

A decrease in olfactory function with age has been attributed to a variety of factors including normal anatomical and physiological changes in aging, surgery, trauma, environmental factors, medications and disease. Olfactory impairment has also been associated with neurodegenerative diseases such as Alzheimer's disease (AD) and Parkinson's disease. Deficits in these chemical senses cannot only reduce the pleasure and comfort from food, but represent risk factors for nutritional and immune deficiencies as well as adherence to specific dietary regimens. Therapy is limited, but one should be aware of the existing medical and surgical treatment modalities. Reactive oxygen and nitrogen species, copper and zinc ions, glycating agents and reactive aldehydes, protein cross-linking and proteolytic dysfunction may all contribute to neurodegeneration, olfactory dysfunction, AD. Carnosine (beta-alanyl- L-histidine) is a naturally-occurring, pluripotent, homeostatic transglycating agent. The olfactory lobe is normally enriched in carnosine and zinc. Loss of olfactory function and oxidative damage to olfactory tissue are early symptoms of AD. Protein and lipid oxidation and glycation are integral components of the AD pathophysiology. Carnosine can suppress amyloidbeta peptide toxicity, inhibit production of oxygen free-radicals, scavenge hydroxyl radicals and reactive aldehydes, and suppresses protein glycation. The observations suggest that patented non-hydrolyzed carnosine lubricant drug delivery or perfume toilet water formulations combined with related moiety amino acid structures, such as beta-alanine, should be explored for therapeutic potential towards olfactory dysfunction, AD and other neurodegenerative disorders. "The olfactory system, anatomically, is right in the middle of the part of the brain that's very important for memory. There are strong neural connections between the two." ~ Donald Wilson.