Peptidomics Analysis of Milk Protein-Derived Peptides Released over Time in the Preterm Infant Stomach

Area of Science:

• Biochemistry
• Pediatric Nutrition
• Proteomics

Background:

• Native milk and infant digestive proteases fragment milk proteins into bioactive peptides during digestion.
• Understanding peptide release is crucial for infant nutrition and health outcomes.

Purpose of the Study:

• To investigate the release and profile of peptides during gastric digestion in preterm infants.
• To compare peptide release in infants fed fortified versus unfortified milk.
• To predict the bioactivity of released peptides.

Main Methods:

• Analysis of milk and gastric samples from 14 preterm infants over 3 hours of digestion.
• Utilized Orbitrap tandem mass spectrometry for peptide extraction and analysis.
• Predicted peptide bioactivity based on sequence homology to known bioactive peptides.

Main Results:

• Both total and bioactive peptide abundance and count increased throughout 3 hours of gastric digestion.
• Milk fortification, adjusted for infant factors, reduced peptide release from human milk proteins.
• Peptides surviving digestion were more structurally similar to known bioactive peptides.

Conclusions:

• Gastric digestion continuously releases peptides, including bioactive ones, from milk in preterm infants.
• Milk fortification may alter the profile of released peptides, potentially affecting their biological relevance.
• This study provides a comprehensive peptide profile during infant gastric digestion, aiding in the identification of biologically relevant peptides.