Related Experiment Videos
An N-terminal peptide from link protein stimulates proteoglycan biosynthesis in human articular cartilage in vitro
L A McKenna1, H Liu, P A Sansom
1The Kennedy Institute of Rheumatology, London, UK.
Objective:
To determine the effects of a synthetic N-terminal peptide from link protein on the synthesis of proteoglycans by human articular cartilage.
Methods:
Explants from adult knee cartilage were maintained for 4 days in serum-free Dulbecco's modified Eagle's medium. Peptides were added for the final 2 days of culture. Synthesis of proteoglycans and proteins was measured by the incorporation of 35S-sulfate and 3H-serine. The sizes, sulfation patterns, and serine: sulfate ratios of newly synthesized glycosaminoglycans were measured by gel chromatography, high performance liquid chromatography, and ion-exchange chromatography.
Results:
The N-terminal peptide stimulated proteoglycan synthesis in cartilage from a wide age range of patients of both sexes. The newly synthesized glycosaminoglycans were identical in size and composition to those of control tissues, and their serine:sulfate ratios remained unchanged.
Conclusion:
This N-terminal peptide, which can be liberated from proteoglycan aggregates by proteolysis, potently stimulated the synthesis of proteoglycans with normal glycosaminoglycan chains. The results suggest that the N-terminal peptide may have a regulatory role in maintaining the integrity of human cartilage matrix.