Intestinal absorption of the intact peptide carnosine in man, and comparison with intestinal permeability to lactulose
Laboratory studyHumans
- Design
- Laboratory study
- Subjects
- not stated in abstract (healthy human subjects)
- Dose used in the study
- not stated in abstract
- Duration
- plasma and urine monitored for 5 hours after ingestion
- What was measured
- Plasma and urinary carnosine and beta-alanine after oral carnosine; urinary lactulose recovery; plasma carnosinase activity; effect of hypertonic solutions.
What the authors reported
The authors report that large amounts of intact carnosine (up to 14% of the ingested dose) were recovered in urine, while plasma carnosine was undetectable unless carnosinase was inhibited ex vivo. Urinary recovery varied widely between subjects and correlated negatively with plasma carnosinase activity, which was highest in subjects who trained regularly. Hypertonic solutions increased lactulose recovery but reduced carnosine recovery, so the paracellular route is probably not the main route for intact carnosine. They conclude that intact carnosine crosses the intestine to a much greater extent than previously recognised, and that rapid post-absorptive hydrolysis makes quantifying intact peptide absorption difficult.
Limits of this study
Small physiological study in healthy volunteers; number of subjects and dose not stated in the abstract. Plasma carnosine could not be measured without ex-vivo carnosinase inhibition.
Source
Entry checked against PubMed Central abstract (PMC1180115); volume and pages not verified on 2026-10-11. The dose shown is the dose the researchers used. It is not a recommendation. How to read this page.