Oral administration of (14)C labeled gelatin hydrolysate leads to an accumulation of radioactivity in cartilage of mice (C57/BL).
Level 5 - mechanism / opinion, no new human data
Animal pharmacokinetic and ex vivo tissue distribution study (CEBM Level 5).
PubMed 10498764 · doi:10.1093/jn/129.10.1891
What was done
Researchers tracked the absorption and tissue distribution of enterally administered (14)C-labeled gelatin hydrolysate compared to (14)C-labeled proline in C57/BL mice over 192 hours by measuring plasma and tissue radioactivity. In addition, ex vivo "gut sac" experiments combined with SDS-electrophoresis and HPLC were used to assess the molecular weight profile of absorbed gelatin peptides.
What was found
Ninety-five percent of the enterally applied gelatin hydrolysate was absorbed within the first 12 hours. Tissue distribution was largely similar to labeled proline except in cartilage, where gelatin hydrolysate accumulated at radioactivity levels more than twice as high as the control group. High-molecular-weight peptides of 2.5-15 kDa were detected following intestinal transit.
Why it matters
This study provides preclinical pharmacokinetic evidence that intact or large-fragment gelatin hydrolysates cross the intestinal barrier and accumulate preferentially in cartilage, offering a plausible mechanism for collagen-derived supplements.
Limits
The study was conducted in mice and ex vivo gut sac models, so translation to human pharmacokinetics is unproven. The abstract does not report the total animal sample size (n), exact variance or confidence intervals, or clinical/functional outcomes on cartilage repair.
Cited by
- partial A rodent study using radiolabeled hydrolyzed collagen demonstrated intact peptides reaching the tendons.