Chondroprotective effect of the bioactive peptide prolyl-hydroxyproline in mouse articular cartilage in vitro and in vivo

Nakatani S, Mano H, Sampei C, Shimizu J, Wada M · Osteoarthritis and Cartilage

Collagen hydrolysate and Pro-Hyp both prevented chondrocyte loss and thinning of the articular cartilage layer in vivo. In vitro Pro-Hyp tripled glycosaminoglycan staining area and roughly doubled aggrecan mRNA. Decisively, a combination of free proline, hydroxyproline and Pro-Hyp-Gly did nothing — the intact dipeptide is the active species, not the amino acids.

Population

C57BL/6J mice fed excess-phosphorus diets (cartilage-loss model), plus ATDC5 chondrocyte cultures

Intervention

Collagen hydrolysate or the dipeptide prolyl-hydroxyproline (Pro-Hyp)

Comparator

Untreated model animals; and, in vitro, free proline + hydroxyproline + the tripeptide Pro-Hyp-Gly

Limitations

Mouse and cell model only; the in vivo model is phosphorus-induced cartilage loss, not osteoarthritis; no human data.