title: Proteochondroitin sulfate synthesized in cartilages induced in vivo and in vitro by bone matrix gelatin.
abstract: Implanted allogeneic demineralized bone matrix gelatin induced sequential development of cartilage and bone in the recipient rat muscle tissue. Proteoglycans of the implants labeled in vivo with [35S]sulfate at different stages of development were analyzed by sucrose density gradient centrifugation. The major proteoglycan synthesized in day-5 implant, just prior to onset of chondrogenesis, was a dermatan sulfate-containing proteoglycan with relatively slow sedimentation rate. Additionally, a small amount of a faster sedimenting component could be detected. The faster sedimenting proteoglycan, in which chondroitin 4-sulfate accounted for 85% of total radioactivity, became predominant in day-10 sample when cartilage formation was maximal. By day 30, when cartilage had been replaced by newly formed bone, the synthesis of this faster sedimenting component had ceased. A similar, if not identical, proteoglycan was found to be a major one synthesized by the in vitro-induced cartilage. This proteoglycan was smaller in overall size and shorter in length of its chondroitin sulfate chains than a major proteoglycan component obtained from neonatal rat epiphyseal cartilage. Concurrent with these changes in proteoglycan type, there appeared to be a change in collagen type, since type II collagen, in addition to type I collagen, was synthesized in day-10 implant. These results indicate that the proteoglycan can be used as a molecular marker for chondrogenesis by bone matrix gelatin.
mesh_terms: D000009:Abdominal Muscles / Q000187:drug effects / Q000378:metabolism*; D000375:Aging; D000818:Animals; D001857:Bone Matrix; D002499:Centrifugation, Density Gradient; D011508:Chondroitin Sulfate Proteoglycans / Q000096:biosynthesis*; D003094:Collagen / Q000096:biosynthesis; D005780:Gelatin / Q000494:pharmacology*; D066298:In Vitro Techniques; D008297:Male; D011509:Proteoglycans / Q000032:analysis / Q000096:biosynthesis*; D051381:Rats
chemical_list: D011508:Chondroitin Sulfate Proteoglycans; D011509:Proteoglycans; D005780:Gelatin; D003094:Collagen