Modelling the ageing gastrointestinal system in-vitro using whey protein isolate

Area of Science:

• Nutritional Science
• Gastroenterology
• Biochemistry

Background:

• Aging and certain health conditions can impair protein digestion and absorption.
• Current in-vitro digestion models may not accurately reflect the unique gastrointestinal environment of older adults.

Purpose of the Study:

• To adapt in-vitro digestion protocols for simulating older adults with gastrointestinal infections or polypharmacy.
• To characterize whey protein digestion under these adapted conditions.
• To understand the impact of altered digestive conditions on protein assimilation in the elderly.

Main Methods:

• Adapted in-vitro digestion protocols simulating gastric and intestinal phases.
• Quantified whey protein breakdown via degree of hydrolysis.
• Assessed bio-accessible peptides and molecular weight distribution (Size Exclusion Chromatography).
• Performed peptide sequencing using High Resolution LC-MS.

Main Results:

• Older adult digestive conditions significantly altered whey protein digestion.
• Observed increased protein aggregates and intact proteins in the gastric phase.
• Reduced bio-accessible peptides were found in the gastric phase.
• Distinct proteolytic profiles were identified in the intestinal digesta.

Conclusions:

• Simulated gastrointestinal conditions must be adapted to accurately represent older adults.
• Altered digestion impacts whey protein breakdown and bio-accessibility in the elderly.
• This research aids in understanding poor protein assimilation in aging populations.