ALINE ANDRES and ROSE ANN MATHAI study how soy infant formula influences neonatal digestive health. (2006)

       The goal of Dr. Sharon Donovan's research is to understand how nutrition influences growth and development of infants with a particular focus on the intestinal tract. Currently, 25 percent of formula-fed infants in the U.S. are consuming soy-based infant formulas that contain biologically active compounds including isoflavones, but few have assessed their potential impact on intestinal health. Graduate students Aline Andres and Rose Ann Mathai currently are addressing this question.

       

       The aim of Andres' doctoral research is to test whether isoflavones, present in soy infant formula, could reduce the severity and duration of rotavirus (RV) infections. “RV is the most common cause of diarrhea in infants and children and is responsible for 440,000 deaths each year worldwide. Currently, there is no vaccine to prevent RV infections, so we are looking at nutritional approaches to reduce the incidence and severity of RV”, she stressed. In collaboration with Dr. Mark Kuhlenschmidt in the Department of Pathobiology, Andres found that isoflavones, at soy formula concentrations, inhibited RV infections by 50 to 60 percent. Now she is conducting a similar study on neonatal piglets fed soy formula and infected with RV. “Piglets are the closest model to the human infant gastrointestinal tract. Thus, our findings will be applicable to human nutrition”, said Andres.

        Originally from France, Andres came to the U of I to pursue a doctoral degree while discovering a new culture and language. One of the highlights of her graduate school experience was to participate in an internship at Mead Johnson, an infant formula company. “Graduate programs open your eyes to the world of academia, but often fail to provide an understanding of nutrition research in the food industry. Being an intern at Mead Johnson was a wonderful learning experience and provided an understanding of how research is applied to product development, while fitting within the management and business environment of a company”, Andres said.

        Rose Ann Mathai is working with Andres to determine how soy formula influences intestinal development and the recovery phase following RV infection. “I came to the U of I after working as a pediatric dietitian for three years”, said Mathai. “My job was to optimize the nutrition for hospitalized children, including those with diarrheal diseases, like RV. The study of soy infant formula was a natural fit for me because of my interest in pediatric nutrition.”

DEE WALKER investigates how high-protein diets affect weight loss and risk factors for the metabolic syndrome. (2006)

       “I've had an interest in nutrition for a number of years. I toyed with going into pharmacy, but then got back on track with nutrition and dietetics. When I talked to Dr. Don Layman about his research, it seemed like a good fit for me.”

        The Layman laboratory is working to define protein and amino acid requirements and the interrelationship between dietary protein and carbohydrates in adult health. Evidence is accumulating that diets with reduced carbohydrates and increased levels of high-quality protein are

the metabolic syndrome. They propose that keys to understanding the relationship between dietary protein and carbohydrates are the relationships between the branched-chain amino acid leucine, insulin and glucose metabolism.

        Two previous short-term human studies conducted by the Layman lab found that human subjects provided with lower carbohydrate, higher protein diets had increased loss of body fat while reducing loss of lean tissue and stabilizing blood glucose compared to subjects on diets consistent with current carbohydrate and protein recommendations. These diets also are highly effective in correcting the dyslipidemia (elevated blood triglycerides and low HDL) associated with the metabolic syndrome.

       “My doctoral research involves a 16-month human weight loss study. This long-term study used both men and women who were totally free living -- no meals were served to them, so they were on their own a lot more. The study confirmed the previous findings -- that those on the higher-protein diet lost more body fat and retained more muscle. Now, I'm evaluating the clinical markers of the metabolic syndrome to determine if overweight individuals who also have metabolic syndrome risk factors benefit more from a high-protein diet”, said Walker.

        “I have enjoyed the ability to collaborate. The professors are always open to ideas and are willing to meet to discuss them. There is also an invisible network that links the grad students and professors in departments all across campus, so that if you have a question, odds are that someone can help you. I plan to get a Ph.D. and also become a Registered Dietitian, which will allow me pursue an academic position and be able to both design experiments and counsel patients.”

ANNE BARTHOLOME travels and collaborates internationally in her program at U of I. (2002)

        “Short-bowel syndrome (SBS) occurs when a large portion of the small intestine has been removed due to disease. Many patients with SBS may require total parenteral nutrition (TPN), intravenous nutrition, to meet their nutritional needs. Even though TPN is beneficial, it can cause intestinal atrophy and inhibit intestinal adaptation. Therefore, my research project examines the effects of TPN supplemented with short-chain fatty acids, by-products of fiber fermentation, on enhancing intestinal adaptation in the neo­natal piglet model. In addition, my research investigates the effect of a hormone on enhancing the small intestine in adults with SBS along with intestinal development in neonatal piglets supported on TPN.

        One of the exciting aspects of my graduate research has been the international collaborations established between the lab run by my advisor, Kelly Tappenden, and research facilities in Denmark. Because of these collaborations, I have had the opportunity to visit Copenhagen on several occasions to transport samples back to Illinois.

        It has been extremely fulfilling to be able to work on a research project that integrates so many aspects of basic sciences and nutrition. From the physiology required to perform surgeries, to biochemistry and chemistry needed to formulate TPN solutions that meet nutritional needs, to the molecular biology required to analyze samples, my research uniquely integrates numerous disciplines with the field of nutrition.”

JAMIE BAUM learns from her professors, other graduate students, and her research subjects. (2002)

        “I'm working with Dr. Don Layman, whose research program focuses on the interrelationship between dietary protein and carbohydrate. We're particularly interested in how a family of essential amino acids, the branched-chain amino acids, affects skeletal muscle protein and blood glucose concentrations. We've found that leucine, one of the three branched-chain amino aids, is unique in its ability to stimulate muscle protein synthesis via the insulin receptor signaling pathway and to improve how the liver regulates blood glucose concentrations. We are currently examining the role of dietary protein in glucose metabolism and the effect this has on

at the molecular level: how leucine affects insulin signaling and glucose use in skeletal muscle and adipose tissue.

        The most rewarding aspect of my graduate studies is the active role I have played in developing my research projects. I have been able to work with both human and animal subjects, which has been an invaluable experience. I have also had the opportunity to collaborate with other professors in the Division, enabling me to learn many new ten lab techniques and meet new people. And my teaching assistantships have allowed me to interact with other graduate students and undergraduates to enhance my teaching skills.”