The goal of this research project is to understand mechanisms regulating pancreatic development and function that are influenced by nutrients and secondary endocrine factors that augment the effects of nutrients and to focus specifically on the limited pancreatic growth and function in fetuses with intrauterine growth restriction (IUGR). We will test the hypothesis that reduced fetal nutrition from placental insufficiency will result in primary nutrient (glucose) and secondary hormonal (insulin, IGFs) deficiencies that lead to abnormal pancreatic endocrine development and function with 3 specific aims. 1. Analyze pancreatic development and function to define critical developmental periods and identify the adaptations imposed by decreased nutrient availability in the IUGR fetus. 2. Determine the effects of nutrient and hormonal deficiencies on insulin production and secretion in pancreatic endocrine cells in the IUGR fetus. 3. Test the ability to restore normal pancreatic development and function by in vivo nutrient and hormonal supplementation during critical periods of development in the IUGR fetus. The proposed studies will be conducted in our ovine model of IUGR produced by maternal exposure to a moderately hyperthermic environment during gestation. These fetuses develop hypoglycemia and hypoaminoacidemia and secondary deficiencies in insulin and GF concentrations in the latter third of gestation. in vivo and in vitro studies will characterize pancreatic development and function and determine mechanisms responsible for pancreatic abnormalities that are direct consequences of fetal nutrient deprivation. The studies also will provide insight into requirements for clinical interventions to ameliorate pancreatic insufficiency in IUGR fetuses and neonates, hopefully to reduce fetal and neonatal morbidity and mortality, and potentially to reduce the incidence of adult onset diseases that have been associated with low birth weight.

Agency
National Institute of Health (NIH)
Institute
Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD)
Type
Research Project (R01)
Project #
5R01HD042815-02
Application #
6612715
Study Section
Special Emphasis Panel (ZRG1-END (02))
Program Officer
Raju, Tonse N
Project Start
2002-04-01
Project End
2007-03-31
Budget Start
2003-04-01
Budget End
2004-03-31
Support Year
2
Fiscal Year
2003
Total Cost
$557,366
Indirect Cost
Name
University of Colorado Denver
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
041096314
City
Aurora
State
CO
Country
United States
Zip Code
80045
Limesand, Sean W; Rozance, Paul J; Macko, Antoni R et al. (2013) Reductions in insulin concentrations and ýý-cell mass precede growth restriction in sheep fetuses with placental insufficiency. Am J Physiol Endocrinol Metab 304:E516-23
Limesand, Sean W; Rozance, Paul J; Brown, Laura D et al. (2009) Effects of chronic hypoglycemia and euglycemic correction on lysine metabolism in fetal sheep. Am J Physiol Endocrinol Metab 296:E879-87
Rozance, Paul J; Limesand, Sean W; Barry, James S et al. (2009) Glucose replacement to euglycemia causes hypoxia, acidosis, and decreased insulin secretion in fetal sheep with intrauterine growth restriction. Pediatr Res 65:72-8
Hay Jr, William W (2008) Strategies for feeding the preterm infant. Neonatology 94:245-54
Limesand, Sean W; Rozance, Paul J; Smith, Danielle et al. (2007) Increased insulin sensitivity and maintenance of glucose utilization rates in fetal sheep with placental insufficiency and intrauterine growth restriction. Am J Physiol Endocrinol Metab 293:E1716-25
Wallace, Jacqueline M; Milne, John S; Aitken, Raymond P et al. (2007) Sensitivity to metabolic signals in late-gestation growth-restricted fetuses from rapidly growing adolescent sheep. Am J Physiol Endocrinol Metab 293:E1233-41
Rozance, Paul J; Limesand, Sean W; Zerbe, Gary O et al. (2007) Chronic fetal hypoglycemia inhibits the later steps of stimulus-secretion coupling in pancreatic beta-cells. Am J Physiol Endocrinol Metab 292:E1256-64
Rozance, Paul J; Hay, William W (2006) Hypoglycemia in newborn infants: Features associated with adverse outcomes. Biol Neonate 90:74-86
Rozance, Paul J; Limesand, Sean W; Hay Jr, William W (2006) Decreased nutrient-stimulated insulin secretion in chronically hypoglycemic late-gestation fetal sheep is due to an intrinsic islet defect. Am J Physiol Endocrinol Metab 291:E404-11
Hay Jr, William W (2005) Intravenous nutrition of the very preterm neonate. Acta Paediatr Suppl 94:47-56

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