The long term goals of the Castillo Laboratory are focused on defining the regulatory mechanisms of nutrient homeostasis under conditions of inflammation and critical illness, and how these processes affect nutrient requirements for nutritional balance and function maintenance. 

We have focused our attention on translational studies on: 

1) Amino acid homeostasis and utilization during enteral or parenteral routes of administration provided to critically ill children. 

2) Parenteral and enteral sulfur amino acid requirements to maintain methylation function and glutathione synthesis rates. 

3) Protein and energy interactions under conditions of inflammation and insulin resistance. 

4) The impact of current critical care practices providing continuous light and feedings on circadian clock mechanisms and insulin resistance in critically ill children. For this purpose, we use stable isotopic mass spectrometric and imagining techniques.