Can trehalose prevent neurodegeneration? Insights from experimental studies.

Inappropriate protein aggregation is a key mechanism in the pathogenesis of several neurodegenerative disorders. One of the main strategies by which cells deal with abnormal protein aggregates is autophagy, a degradation pathway for intracellular aggregate-prone proteins. Trehalose, a non-reducing disaccharide which has been utilized extensively in the food industry, has been recently demonstrated to have a number of unique properties that point to its potential utility in preventing neurodegeneration. First, trehalose may act as a potent stabilizer of proteins and is able to preserve protein structural integrity. Second, it is a chaperone and reduces aggregation of pathologically misfolded proteins. Third, it improves the clearance of the mutant proteins which act as autophagy substrates when aberrant protein deposition occurs. Notably, trehalose is an mTOR-independent inducer of autophagy, and in animal models of neurodegenerative disorders including Alzheimer's disease, Parkinson's disease, and Huntington's disease, has been shown to decrease the levels of toxic protein aggregates, increase autophagy, and improve clinical symptoms and survival. In summary, mounting experimental evidence suggests that trehalose may prevent neurodegenerative disorders by stabilizing proteins and promoting autophagy. Because of the low toxicity profile that allows for administration for extended periods, human studies of trehalose in preventing neurodegeneration are warranted.