Dr. Sue Houston has co-authored the first book about nutrition and insulin-like growth factors.

BGSU researcher’s book is first to focus on insulin-like growth factors and nutrition

Since insulin-like growth factors (IGF) were first identified in the late 1950s, physicians and researchers have been avidly studying the role they play in almost every aspect of human and animal health and development.

A new book co-authored and edited by Dr. Sue Houston, Food and Nutrition Program in the School of Family and Consumer Sciences, is the first to concentrate on the interactions of the IGF system
and nutrition.

IGF and Nutrition in Health and Disease, recently published by the Humana Press, brings together research from leading experts in the field to explain how specific nutrients or adverse nutritional states impact the components of the IGF system and affect human health and disease.

Chapter authors come from prestigious U.S. and European universities, the National Institutes of Health and the World Heath Organization, and represent the diverse yet interrelated disciplines such as endocrinology, molecular biology, animal science, physiology, medicine and nutrition that are involved in IGF research. “They are an interesting and strong group,” Houston said. “Their research really gets to the basic mechanism of how we grow and how health is maintained. The book also explores the interrelationships between nutrition and the IGF in disease states, both chronic and acute. Understanding IGFs will be increasingly important in disease prevention and development of effective therapies.”

In the book’s preface, she and co-editors Dr. Jeffrey M.P. Holly of the University of Bristol, U.K., and Dr. Eva Feldman of the University of Michigan Medical Center write “The complexity and significance of the insulin-like growth factor (IGF) system is staggering. From conception through postnatal growth, development, reproduction and aging, in health and disease, the IGF axis orchestrates critical aspects of metabolism and physiology.”

IGFs are found in all cells in the body, Houston said. Though actually a family of proteins and receptors, the system behaves like a hormone in its ability to influence cell activity. IGF proteins are involved in DNA and protein synthesis, cell division and death. IGFs have insulin-like activities and mediate the effects of growth hormone on bone development. Thus the IGFs participate in many aspects of metabolism and growth–both normal and abnormal. One of the most profound regulators of the IGF system is nutritional status.

“We know that with inappropriate dietary intake, growth, development and health are affected,” Houston said. “So we want to look at the interface of IGF and cell nutrition, physiology and metabolism. We’re looking at how nutrients and dietary components signal the body to develop and interact with IGFs.

“The flip side is that some of the IGF proteins are really good markers for malnutrition, such as protein or zinc deficiencies that might be affecting a body’s ability to grow or function.” Houston’s chapter reviews the use of IGF proteins as sensitive markers of nutritional and metabolic status in a variety of conditions, including starvation, cancer and other conditions where the ability to maintain weight becomes a survival issue.

Houston, who specializes in nutrition science, has investigated the role of nutrients in how the IGF system responds to changes in circumstances in both animals and humans. She has been involved in projects with St. Vincent’s Mercy Medical Center and the Medical College of Ohio in Toledo to learn how to better nourish trauma patients, for example.

Normally, blood tests can help determine if a person is getting appropriate nutrition. However, in critical illness where the body is experiencing stress, inflammation or infection, those markers may not be reliable. And yet these are the times when avoiding overfeeding and underfeeding becomes critical to survival, Houston said. Her research suggests that measuring IGFs in the blood can help to appropriately feed these critically ill patients.

Another part of her research, with Dr. Cynthia Smas of MCO, focuses on nutrients and phytochemicals—bioactive compounds in food such as lycopene in tomatoes and ellagic acids in blueberries—which might play a role in prevention or treatment of diseases such as prostate cancer.

In fact, IGFs are a “hot topic” in cancer research, Houston said. Because they can influence both cell growth and death, finding ways to “turn off” cancer cells is another way in which nutrition and the IGF axis likely interact.

Other chapters in the book highlight the involvement of IGFs in fetal development, aging, diabetes, cardiovascular disease, neurology, osteoporosis and kidney and gastrointestinal diseases, among others.

In short, a fuller understanding of the IGF system and nutritional states has tremendous potential
for understanding “fundamental biological processes, disease prevention, therapy and health,” the
authors write.