Mucin 2 (MUC2) is the structural component of the protective mucus layer of the gastrointestinal tract, and is secreted by goblet cells.¹ MUC2 is a glycoprotein that contains high amounts of threonine and proline residues.^2,3 Recently, we showed that almost 90% of dietary threonine is utilised by the intestine of piglets in first pass.⁴ This high visceral threonine requirement presumably reflects the high synthesis rate of MUC2. In this context, threonine might be of critical nutritional importance in maintaining good intestinal barrier function. Neonates with impaired gut function following bowel resection require adequate gut adaptation and recovery of intestinal barrier function to avoid the consequences of malabsorption of dietary nutrients and pathogenic bacterial insults. We therefore used a tracer method to study the role of dietary threonine in intestinal MUC2 synthesis and to calculate the fractional synthetic rate (FSR) of small intestinal MUC2 in human neonates as a parameter for intestinal barrier function.

Five …