Publications

Abstract Numerous experimental and clinical observations suggest that overall changes in bone resorption during menopause or treatment with hormone replacement therapy (HRT) are combined effects of changes in osteoclast number and function. Moreover, due to a coupling between osteoclastic bone resorption and osteoblastic bone formation, pronounced alteration of osteoclast number will eventually lead to alteration […]

Abstract OBJECTIVE Calcitonin has been suggested to have chondroprotective effects. One signaling pathway of calcitonin is via the second messenger cAMP. We undertook this study to investigate whether increased cAMP levels in chondrocytes would be chondroprotective. METHODS Cartilage degradation was induced in bovine articular cartilage explants by 10 ng/ml oncostatin M (OSM) and 20 ng/ml […]

Abstract OBJECTIVE Aggrecan is the major proteoglycan in articular cartilage and is known to be degraded by various proteases, including matrix metalloproteinases (MMPs). The present study was undertaken to develop immunoassays detecting aggrecan and its fragments generated by MMP and non-MMP-mediated proteolysis. METHODS Two immunoassays were developed: (1) the G1/G2 sandwich assay employing a monoclonal […]

Abstract Bone resorption is solely mediated by osteoclasts. Therefore, a pure osteoclast population is of high interest for the investigation of biological aspects of the osteoclasts, such as the direct effect of growth factors and hormones, as well as for testing and characterizing inhibitors of bone resorption. We have established a pure, stable, and reproducible […]

Abstract Collagen characteristics contribute to bone biomechanical properties. Yet, few studies have analyzed the independent contributions of bone mineral density (BMD) and post-translational modifications of type I collagen to whole bone strength. Thus, the aim of this study was to determine the relative contributions of BMD and both enzymatic and non-enzymatic collagen crosslink concentration to […]

Abstract OBJECTIVE To investigate changes in the circulating levels of the C-telopeptide of type II collagen (CTX-II) with relation to disease onset and structural damage of cartilage in a rodent model of collagen-induced arthritis (CIA), and to investigate immunolocalization of the CTX-II epitope in the articular cartilage of affected joints. METHODS Seven-week-old female Lewis rats […]

Abstract OBJECTIVE Calcitonin was recently reported to counter progression of cartilage degradation in an experimental model of osteoarthritis, and the effects were primarily suggested to be mediated by inhibition of subchondral bone resorption. We investigated direct effects of calcitonin on chondrocytes by assessing expression of the receptor and pharmacological effects on collagen type II degradation […]

Abstract OBJECTIVE To investigate how the time of initiation influences the effects of estrogen therapy on type II collagen (CII) turnover and the structural integrity of articular cartilage in ovariectomized rats and to determine whether estrogen exerts direct effects on the catabolic function of chondrocytes ex vivo. METHODS A total of 46 Sprague-Dawley rats were […]

Abstract OBJECTIVE Osteoarthritis (OA) is the most common form of degenerative joint diseases and a major cause of disability and impaired quality of life in the elderly. Recent observations suggest that calcitonin may act on both osteoclasts and chondrocytes. The present review was sought to summarize emerging observations from the molecular level to the preliminary […]

Abstract We recently showed that increased urinary excretion of the cross-linked, nonisomerized form of the C-telopeptide of collagen type I (alphaalphaCTX) could be a sensitive indicator of the presence of bone metastases in breast cancer patients. The present study was sought to investigate (a) the localization of alphaCTX epitopes in the proximity of a bone […]