URBANA, Ill. — When we eat sugar, a portion of it is stored as glycogen in our liver and muscles, where it can be quickly metabolized to glucose for bursts of energy. But the uterus also stores the molecule, a long-known but scientifically overlooked observation University of Illinois Urbana-Champaign researchers hope to exploit to solve perplexing questions related to infertility and pregnancy failure.

Matt Dean, assistant professor in the Department of Animal Sciences and the Division of Nutritional Sciences in the College of Agricultural, Consumer and Environmental Sciences (ACES) is principal investigator on a new $1.9 million National Institutes of Health grant to investigate the role of glycogen in supporting healthy pregnancies.

“About 50% of pregnancies in women and cows fail, often very early. During that time, glucose is a very important nutrient for the uterus and developing embryo. We know if the uterus doesn't have enough glucose, the pregnancy fails. And if it has too much, the pregnancy will also fail,” Dean said. “We think the uterus is using pools of glycogen as a buffer to maintain just the right amount of glucose in different parts of the uterus as the pregnancy progresses.” 

The five-year project, which also includes animal sciences faculty Romana Nowak, Kelly Swanson, and Bruce Southey, will be the first to link glycogen in the uterus with fertility. Specifically, the team will study transgenic mice that are unable to store glycogen in the uterus, with the hypothesis that fertility will take a major hit. The researchers will also investigate how obesity in mice affects uterine glycogen storage, providing clues to explain why obese women experience lower fertility.

“Obesity affects the reproductive system in a lot of ways, including changes in glucose and insulin concentration. But again, no one has considered glycogen,” Dean said. “We're looking at how obesity changes glycogen storage in the uterus, with the idea that it may not be able to metabolize glycogen correctly, maybe storing too much or too little.”

The team hopes to eventually translate what they learn in mice to women and livestock, with the ultimate goal of optimizing glycogen concentrations to avoid pregnancy loss.

This research is supported by the Eunice Kennedy Shriver National Institute of Child Health and Human Development of the National Institutes of Health under award number R01HD111706. The five-year, $1.9 million project is financed wholly with federal money. This content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.