The aim of this work was to study the ontogeny of chondrocyte cell division using embryo, adult and osteoarthritic(OA) cartilage. We searched for mitosis phases and performed a comparative evaluation of mitotic index,...The aim of this work was to study the ontogeny of chondrocyte cell division using embryo, adult and osteoarthritic(OA) cartilage. We searched for mitosis phases and performed a comparative evaluation of mitotic index, basic fibro-blast growth factor b (FGFb), transforming growth factor β1 (TGF-β1) receptors, cyclin dependent kinase (CDK1)and Cyclin-B expression in fetal, neonate, 3, 5, 8 weeks old rats and experimental OA. Our results showed that mitosisphases were observed in all normal cartilage studied, although, we found a decrease in mitotic index in relation to tissuedevelopment. No mitosis was detected in OA cartilage. We also found a statistical significant reduction in cell number inOA cartilage, compared with the normal tissue. Furthermore, FGFb and TGF-β1 receptors diminished in relation totissue development, and were very scarce in experimental OA. Western blot assays showed CDK-1 expression in allcases, including human-OA cartilage. Similar results were observed for Cyclin-B, except for 8 weeks, when it was notexpressed. Our results suggest that cell division seems to be scarce, if not absent within the OA cartilage studied.Nevertheless, the existence of factors essential for cell division leaves open the question concerning chondrocyteproliferation in OA cartilage, which is likely to be present in the early stages of the disease.展开更多
文摘The aim of this work was to study the ontogeny of chondrocyte cell division using embryo, adult and osteoarthritic(OA) cartilage. We searched for mitosis phases and performed a comparative evaluation of mitotic index, basic fibro-blast growth factor b (FGFb), transforming growth factor β1 (TGF-β1) receptors, cyclin dependent kinase (CDK1)and Cyclin-B expression in fetal, neonate, 3, 5, 8 weeks old rats and experimental OA. Our results showed that mitosisphases were observed in all normal cartilage studied, although, we found a decrease in mitotic index in relation to tissuedevelopment. No mitosis was detected in OA cartilage. We also found a statistical significant reduction in cell number inOA cartilage, compared with the normal tissue. Furthermore, FGFb and TGF-β1 receptors diminished in relation totissue development, and were very scarce in experimental OA. Western blot assays showed CDK-1 expression in allcases, including human-OA cartilage. Similar results were observed for Cyclin-B, except for 8 weeks, when it was notexpressed. Our results suggest that cell division seems to be scarce, if not absent within the OA cartilage studied.Nevertheless, the existence of factors essential for cell division leaves open the question concerning chondrocyteproliferation in OA cartilage, which is likely to be present in the early stages of the disease.
