Researchers believe the discovery could help those who suffer from amyotrophic lateral sclerosis (ALS), a neurodegenerative disease affecting motor neurons.
ALS patients exhibit neurodegeneration that can lead to paralysis and ultimately death three to five years after the onset of symptoms. No cure is available for patients and the only approved drug, riluzole, has modest effects.
Using results from previous research, the team from the University of Montreal Hospital Research Centre added maple syrup to the diet of C. elegans worms, after it was discovered that sugar prevented the occurrence of ALS.
Here, the worms were genetically modified to express a protein involved in ALS' negative effect on motor neurons – TDP-43 - resulting in motor neuron breakdown after 12 days. After two weeks, half the worms were completely paralysed.
The maple syrup was distributed at various concentrations and compared with a control group given a normal diet.
After 12 days, both the moving and paralysed worms were recorded using microscopic analysis. The worms given the highest dose of syrup were much less likely to be paralysed. Specifically, in those that received a diet enriched with 4% maple syrup, only 17% were paralysed.
Maple syrup’s active compunds
Recently, a list of the most prominent phenols that were found in phenolic rich extract of maple syrup was published.
Four of these compounds, Catechol, Gallic acid, 3,4-dihydroxybenzaldehyde, and Syringaldehyde were identified as present in maple syrup and selected for further study.
“Our data suggest that by themselves phenols found in maple syrup can regulate proteotoxicity (toxicity caused by proteins). The concentration of these phenols in maple syrup is likely much lower than the concentrations we tested individually,” the team noted.
“However, since pure maple syrup shows a stronger neuroprotective effect, the sugars and phenols may have a greater and broader efficacy when combined.”
While the neuroprotective effects of active compounds such as resveratrol, as well as other phenols or antioxidants have been reported in in vitro and in vivo models, including rats, and mice the effectiveness of natural products, is less studied.
Maple syrup contains mainly sucrose (98%) but also includes antioxidants and many different phenols, including Quebecol that is only found in maple syrup.
These phenols found in natural products have also been shown to affect nucleic acids, proteins and cellular membranes. The effect of some phenols found in maple syrup, including those tested, resulted in lifespan extension and could exert an antimicrobial effect.
Source: Journal of Agricultural Food and Chemistry
Published online ahead of print, DOI: 10.1021/acs.jafc.5b05432
“Maple syrup decreases TDP-43 proteotoxicity in a C. elegans model of ALS.”
Authors: Catherine Aaron, Gabrielle Beaudry, Alex Parker, and Martine Therrien