2009 Annual Report
1a.Objectives (from AD-416)
There is an ongoing need to enhance our understanding of the role of various nutrients on fetal, postnatal, and childhood growth and development. This is becoming increasingly important as studies continue to show an association between the patterns of growth during these early time periods and health later in life. At present, little is known about the functional need for different amino acids in support of these changes, and the variability in normal growth. The research objectives include:.
1)define the normal range of biological diversity in body composition during specific periods of human growth;.
2)define the nutritional and functional requirements of methionine, cysteine, and arginine for healthy children;.
3)investigate the impact of docosahexaenoic acid (DHA) intake from food and supplemental sources on blood levels, cognitive performance, and neurophysiological function, heart rate and blood pressure, as well as a lower incidence of allergies and upper respiratory infection in children;.
4)investigate the pathways and nutritional modulation of methyl group production in underweight and normal weight pregnant women; and.
5)investigate differences in bowel flora, antioxidant capacity, and mitochondrial integrity between severely malnourished and well-nourished children. This project will provide novel and new information directly useful to nutritional scientists, pediatricians, industry, and governmental agencies responsible for establishing pediatric dietary guidelines. These data will have global application and provide a strong basis for evidence-based development of nutritional recommendations for children and pregnant mothers.
1b.Approach (from AD-416)
The goal of our research is to obtain better data on amino acid nutritional and functional requirements for growth and to develop reference standards for body composition during different phases of growth that can be used in the development of nutritional guidelines. Our researchers aim to determine if an intake of methionine and cysteine is more efficient to support glutathione synthesis rates in healthy children, than an equimolar intake of methionine alone. We will evaluate whether arginine supplementation in obese children improves insulin sensitivity and protein synthesis, and explore gluconeogenesis under these conditions. We will investigate the impact of docosahexaenoic acid (DHA) intake from food and supplemental sources on blood levels, cognitive performance, and neurophysiological function of 4- to 12-year-old children. We will establish reference standards for healthy growth in terms of changes in the body's muscle, protein, bone, and fat content.
More than 1,200 whole-body DXA scans for the younger and smaller children in the Children's Nutrition Research Center database had been obtained with an older software version. Each scan had to be reanalyzed with the release of the newest software version by the DXA manufacturer and assessed individually. Also, specialized statistical-based software was obtained and used to perform LMS modeling of body composition in children during growth. On-line training on use of the software was completed, and adjustable parameters were derived to match the Children's Nutrition Research Center reference pediatric population. Recruitment is ongoing, and milestones are on schedule. A small number of subjects have been studied, but we aim to have more data for the Nutrition meetings deadlines this fall. The pilot studies are completed and we are now reassessing sample size based on preliminary data. (Project 1)
The clinical study of gut microbiota is well underway; 300 twin pairs are under surveillance. There have been no problems with initiating this portion of the study. (Project 2)