Abstract
Determine the kinetics of collagen crosslinking in adult bovine articular cartilage explants using radiolabel pulse-chase studies. Explant cultures of adult bovine articular cartilage were radiolabeled with [14C]lysine in medium including fetal bovine serum and ascorbate, and then maintained for chase periods up to 28 days. In some samples, beta-aminopropionitrile (BAPN) was included during chase to inhibit lysyl oxidase-mediated collagen crosslinking. Tissue was hydrolyzed and analyzed for [14C]metabolites in the forms of lysine, hydroxylysine, dehydrodihydroxylysinonorleucine (DeltaDHLNL), and hydroxylysyl pyridinoline (HP). Explant cultures of adult bovine articular cartilage metabolized lysine into hydroxylysine and the collagen crosslinks, DeltaDHLNL and HP. During chase, [14C]hydroxylysine maintained steady-state levels, [14C]DHLNL rose to a plateau, and [14C]HP increased gradually. Addition of BAPN inhibited formation of [14C]DHLNL. Analysis of raw data and that normalized to [14C]hydroxylysine gave characteristic time constants for formation of DeltaDHLNL and HP crosslinks of 1-2 and 7-30 days, respectively. The distribution of [14C]lysine metabolites in collagen crosslinks was described by peak values in [14C]DHLNL/[14C]hydroxylysine of 0.047-0.064 and in [14C]HP/[14C]hydroxylysine of 0.03. Collagen crosslinks form in cartilage explants in vitro according to the classical lysyl oxidase-mediated pathway.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
