Michelle Mondoux, Holy Cross – Sugar, Sex and Aging

New research into how we process sugar on a molecular level are offering insights into our bodies.

Michelle Mondoux, biologist at College of the Holy Cross, discusses her experiments.

Michelle A. Mondoux, Ph.D. is an assistant professor in the department of Biology at the College of the Holy Cross in Worcester, MA. Dr. Mondoux earned her bachelor’s degree in Biological Sciences at Smith College and her Ph.D. in Molecular Biology at Princeton University. She began using C. elegans to model the response to a high-glucose diet during her postdoctoral fellowship at the National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health.

Dr. Mondoux works closely with Holy Cross undergraduates in her research lab, which seeks to understand the effects of a high-glucose diet on the cellular and molecular level.

Sugar, Sex and Aging

Americans consume a lot of sugar—every day, the average person eats about twice as much as the American Heart Association recommends.  Sugar consumption has been linked to diseases like obesity and diabetes, and indirectly to aging and longevity. 

Although we know that high-sugar diets are linked to disease, scientists don’t really understand how this much sugar affects our cells on the molecular level.  My lab and many others use the model organism Caenorhabditis elegans to work on this problem.  C. elegans is a small nematode worm, and like us, these worms have an insulin-signaling system that responds to glucose.

Several labs have demonstrated that feeding worms a high-glucose diet causes them to die sooner and be less healthy in their old age.  However, none of these experiments have included males. 

Together with three undergraduates in my lab–Marjorie Liggett, Mike Hoy, and Mike Mastroianni—we tested how glucose affects males.  Surprisingly, we found that males fed a high-glucose diet do not die sooner—in fact, they lived a little bit longer on the high-glucose diet compared to their normal diet.  Even more surprising, these males were healthier: glucose feeding greatly increased the speed at which the old males moved.   

Our data shows that even within the same species, the effects of a high-glucose diet are not ‘universal’.  More research is needed to understand how a high-glucose diet produces these benefits for male worms as they age, and how this might be relevant to humans.  Eventually, understanding why glucose has benefits for male worms as they age could help us to combat the effects of a high-sugar diet for humans. 

Read More: Aging: High-glucose diets have sex-specific effects on aging in C. elegans: toxic to hermaphrodites but beneficial to males