Publications

Abstract Biglycan is a small leucine-rich proteoglycan which is localized in the extracellular matrix of bone and other specialized connective tissues. Both biglycan mRNA and protein are up-regulated by transforming growth factor-beta(1) (TGF-beta(1)) and biglycan appears to influence TGF-beta(1) activity. In this study, we have investigated the mechanism by which TGF-beta(1), TGF-beta(2) and TGF-beta(3) stimulate […]

Abstract OBJECTIVE Several observational studies indicate that estrogen deficiency increases the incidence of osteoarthritis in postmenopausal women. To validate this observation, we investigated the effects of ovariectomy (OVX) on cartilage erosion in rats using histology and an established bio-assay of cartilage-specific collagen type II degradation products (CTX-II). Furthermore, we investigated whether estrogen and levormeloxifene, a […]

Abstract UNLABELLED Chloride channel activity is essential for osteoclast function. Consequently, inhibition of the osteoclastic chloride channel should prevent bone resorption. Accordingly, we tested a chloride channel inhibitor on bone turnover and found that it inhibits bone resorption without affecting bone formation. This study indicates that chloride channel inhibitors are highly promising for treatment of […]

Abstract Autosomal dominant osteopetrosis II (ADOII) is a relatively benign disorder caused by a missense mutation in the ClCN7 gene. In this study, we characterize the osteoclasts from patients with ADOII, caused by a G215R mutation, and investigate the effect on osteoclast function in vitro. Osteoclasts from ADOII patients and healthy age- and sex-matched controls, […]

Abstract Osteoblasts undergo apoptosis or differentiate into either osteocytes or bone-lining cells after termination of bone matrix synthesis. In this study, we investigated the role of matrix metalloproteinases (MMPs) in differentiation of osteoblasts, bone formation, transdifferentiation into osteocytes, and osteocyte apoptosis. This was accomplished by using calvarial sections from the MT1-MMP-deficient mouse and by culture […]

Abstract OBJECTIVE Glucosamine sulphate has been shown in a large double-blind, placebo-controlled clinical trial to prevent structural damage and improve clinical symptoms of osteoarthritis (OA). We investigated whether early response in a newly developed biochemical marker of collagen type II degradation (CTX-II, CartiLaps ELISA) could reflect the long-term preservation of hyaline cartilage. METHODS Study subjects […]

Abstract Osteoclasts require matrix metalloproteinase (MMP) activity and cathepsin K to resorb bone, but the critical MMP has not been identified. Osteoclasts express MMP-9 and MMP-14, which do not appear limiting for resorption, and the expression of additional MMPs is not clear. MMP-12, also called metalloelastase, is reported only in a few cells, including tissue […]

Abstract Proteins are complex organic molecules susceptible to numerous post-translational modifications occurring spontaneously during aging or as a consequence of physiologic or pathologic processes. Antigenicity and interactions of proteins with components of the immune system may be profoundly affected by post-translational modifications. Thus, modified self-antigens may be absent (not-tolerated) during early T-cell selection and trigger […]

Abstract We aimed to assess the effect of ovariectomy on cartilage turnover and degradation, to evaluate whether ovariectomized (OVX) rats could form an experimental model of postmenopausal osteoarthritis. The effect of ovariectomy on cartilage was studied using two cohorts of female Sprague-Dawley rats, aged 5 and 7 months. In a third cohort, the effect of […]

Abstract The Arguello model of cancer metastasis to bone has been used extensively to study breast cancer-induced osteolytic disease. The effects of therapy on skeletal disease and on tumour burden in soft organs are traditionally measured using radiography and/or time-consuming histomorphometry, respectively. The purpose of this study was to develop a sensitive and efficient method […]