A Maple Syrup Extract Prevents β-Amyloid Aggregation.

During our systematic search for natural product-based anti-protein misfolding agents for the putative treatment of Alzheimer’s disease (AD), we investigated maple syrup. Canada is the world’s largest producer of maple syrup, accounting for 80% of global output; 2013 annual production was 46 million litres. Maple syrup is produced by thermal evaporation of the sap from maple (Acer) trees, a process which concentrates the contained sugars as well as producing a variety of chemical reactions responsible for the distinct colour and taste of the syrup. In addition to the sugars (predominantly α-D-glucopyranosyl(1→ 2)-β-D-fructofuranoside), the collected sap contains a wide range of naturally occurring oligosaccharides, amino acids, polyphenols and phytohormones. The prolonged high temperature thermal process involved in producing syrup from sap also results in the formation of a variety of other phenolic by-product compounds. Maple syrup extracts have been reported to exhibit a variety of health-related properties including antioxidant, antimutagenic and anti-cytoproliferative activities. In this study we demonstrate that an ethyl acetate maple syrup extract decreases oligomerization and aggregation of both β-amyloid (Aβ) and tau peptides in vitro, the two pathological hallmarks of AD.