The benefits people receive from exercise, such as improved cognition over the lifespan and disease prevention, are reinforced by new research and promoted to the public on an almost daily basis. But this growing emphasis also brings about questions, such as its impact on the body and whether exercise alone is enough to counteract age-related conditions.

Beckman Institute researcher Marni Boppart addresses these questions and others at the fundamental levels of cells and molecules in work at the Molecular Muscle Physiology Laboratory she directs at Beckman.

Boppart has created a unique research line as she applies cell and developmental biology to kinesiology in ways that haven’t been done before. Her goals are to gain a greater understanding of the effects of exercise and mechanical strain on muscle, and to translate that work into novel interventions that could serve to complement exercise when it comes to preventing the muscle loss that comes with aging.

The Molecular Muscle Physiology Laboratory is unique for its study of musculoskeletal remodeling and growth in response to exercise and mechanical strain, and as one of the few places where researchers have the ability to manipulate muscle stem cells and investigate the role they play in those processes.

Boppart, who earned a Sc.D. in Applied Anatomy and Physiology from Boston University, came to Illinois in 2000 as a postdoctoral researcher in the Department of Cell and Developmental Biology. She is now an Assistant Professor in the Department of Kinesiology and Community Health and full-time member of Beckman’s Bioimaging Science and Technology group.

In her research Boppart has been able to develop new methods for extracting stem cells from pre-clinical models and use them to study their effects on muscle in response to exercise. It is work that has led to a growing list of projects, papers, collaborators, and new research opportunities.     

“I love coming into work every day because it is so exciting,” she said. “I try to keep our work focused and not get too far out of my realm. But sometimes it’s hard. Where do you set your limits in terms of how these stem cells interact with these other tissues?

“We’re one of the only labs in the world that knows how to isolate these stem cells and manipulate them in a culture,” Boppart added. “Of course we want to learn everything we can about these cells, inject them, and see what happens.”

One example of what’s been happening was reported in a recent paper in the journal PLoS ONE that drew national attention for the discovery that a single bout of exercise in mice led to an increase in mesenchymal stem cells (MSCs) that reside in skeletal muscle. The findings have relevance for understanding the critical links between exercise and whole body health.

“We think that it’s very important for us to translate this work to the human condition,” Boppart said. “We are very excited because this work is an important step towards developing effective interventions that can prevent the loss of muscle that occurs with aging and disease.”

Muscle-derived mesenchymal stem cells (or mMSCs) play a role in regeneration response to injury or disease in skeletal muscle, and Boppart’s lab is leading the way in the study of them. The PLoS ONE paper emphasized the importance of understanding the processes underlying skeletal muscle regeneration.

“What we’ve been able to show in this paper and our current work is that mMSCs are not directly contributing to muscle growth, but do in fact secrete a variety of different factors that positively impact muscle regeneration and growth” Boppart said. “The cells usually respond to injury but in the case of exercise what we think, and this is a very novel phenotype for these cells, is that they secrete the factors specifically in response to mechanical strain.”

Boppart’s research for many years has focused on the a7 integrin receptor – a molecule that mediates connections between cells and tissues – for its role in biological processes such as protecting against injury and regulating exercise-induced muscle growth.   

“We’ve found that the a7 integrin and these stem cells, which are usually positively correlated, are both markedly decreased with age,” she said. “And so we’re trying to determine if we can somehow revitalize stem cell proliferation and function in some way.”