Searchable abstracts of presentations at key conferences on calcified tissues

ba0001pp206 | Cell biology: osteoblasts and bone formation | ECTS2013

Serum sclerostin does not reflect its expression in bone, but is related to bone mineral density

Bravenboer Nathalie , Visser Ruben , den Heijer Martin , Heijboer Annemieke

Sclerostin is a major negative regulator of osteoblastic activity. Serum sclerostin has a weak positive association with BMD but contradictory results have been described concerning associations with fractures. These contradictions could be explained by the fact that serum sclerostin does not reflect its action in bone. In this study we question whether serum sclerostin is associated with its expression in bone. In addition we aimed to detect associations between sclerostin in...

ba0003pp382 | Other diseases of bone and mineral metabolism | ECTS2014

Osteogenic differentiation of fibroblast derived from patients with fybrodisplasia ossificans progressiva

Bravenboer Nathalie , Micha Dimitra , van Essen Huib , Netelenbos Coen , Eekhoff Marelise , Pals Gerard

Fibrodysplasia ossificans progressiva (FOP) is a rare, extremely disabling genetic disorder characterized by progressive heterotopic ossification preceded by episodic inflammatory soft tissue swellings (flare ups) leading to early death. There is no proven effective treatment yet. We aimed to develop an in vitro system to investigate the working mechanism of flare ups induced ossification.Skin biopsies were obtained from four patients with FOP. ...

ba0004oc17 | (1) | ICCBH2015

Inhibition of TGFβ signalling delays ossification in patients with fibrodysplasia ossificans progressiva

Micha Dimitra , Voermans Elise , Huib van Essen , Drukker Jesse , Netelenbos Coen , Eekhoff Marelise , Bravenboer Nathalie

Fibrodysplasia ossificans progressiva (FOP) is a rare congenital disorder characterized by progressive heterotopic ossification. FOP patients only present great toe malformations at birth. However, as they grow older they develop soft tissue lumps as a result of flare-ups causing the irreversible replacement of skeletal muscle tissue with bone tissue leading to cumulative physical immobility. Classical FOP patients possess a mutation (c.617G>A; R206H) in the activin recept...

ba0005ni8 | Abstract Presentations | ECTS2016

Bone marrow adipose tissue and bone turnover in postmenopausal osteoporotic women and the effects of raloxifene

Beekman Kerensa , Heijer Martin den , Maas Mario , Bisschop Peter , Bravenboer Nathalie

Background: In postmenopausal osteoporosis, a loss of bone volume due to increased bone turnover is accompanied by a higher volume of bone marrow adipose tissue (BMAT). If this static relationship is based on a functional relationship, BMAT is a potential target for treating osteoporosis. While it is known that estrogen can reduce BMAT, it is still unknown whether raloxifene – a selective estrogen receptor modulator – can also reduce BMAT.Objec...

ba0005p79 | Bone Marrow | ECTS2016

Bone marrow adipose tissue and bone turnover in postmenopausal osteoporotic women and the effects of raloxifene

Beekman Kerensa , den Heijer Martin , Maas Mario , Bisschop Peter , Bravenboer Nathalie

Background: In postmenopausal osteoporosis, a loss of bone volume due to increased bone turnover is accompanied by a higher volume of bone marrow adipose tissue (BMAT). If this static relationship is based on a functional relationship, BMAT is a potential target for treating osteoporosis. While it is known that estrogen can reduce BMAT, it is still unknown whether raloxifene – a selective estrogen receptor modulator – can also reduce BMAT.Objec...

ba0003pp292 | Osteoporosis: pathophysiology and epidemiology | ECTS2014

CXCL8 and CCL20 enhance osteoblast-mediated osteoclastogenesis

Pathak Janak L , Bakker Astrid D , Verschueren Patrick , Lems Willem F , Luyten Frank P , Klein-Nulend Jenneke , Bravenboer Nathalie

Osteoporosis is common in rheumatoid arthritis (RA). Since osteoblasts express receptors for CXCL8 and CCL20, which are produced by inflammatory cells around the inflamed joints in RA, we hypothesized that CXCL8 and CCL20 contribute to osteoporosis in RA by affecting osteoblast proliferation, differentiation, and osteoblast-osteoclast communication.Primary human osteoblasts were cultured±CXCL8 (2–200 pg/ml) and CCL20 (5–500 pg/ml) for 14 d...

ba0005p43 | Bone development/growth and fracture repair | ECTS2016

Serum of patients with active rheumatoid arthritis inhibits differentiation of osteochondrogenic precursor cells

Pathak Janak L , Verschueren Patrick , Lems Willem F , Bravenboer Nathalie , Klein-Nulend Jenneke , Bakker Astrid D , Luyten Frank P

Delayed fracture healing is frequently experienced in patients with systemic inflammation such as during rheumatoid arthritis (RA). The reasons for this are diverse, but could also be caused by inflammatory cytokines and/or growth factors in serum from patients with active disease. We hypothesized that serum from patients with active RA contains circulating inflammatory factors that inhibit differentiation of osteochondrogenic precursors.Serum was obtain...

ba0005p197 | Cell biology: osteoclasts and bone resorption | ECTS2016

Effects of TGF-β inhibition on osteogenesis and osteoclastogenesis by periodontal ligament fibroblasts from patients with fibrodysplasia ossificans progressiva

de Vries Teun J. , Schoenmaker Ton , Micha Dimitra , Netelenbos Coen , Pals Gerard , Eekhoff Marelise W. , Bravenboer Nathalie

Background: Fibrodysplasia Ossificans Progressiva (FOP) is a progressive disease characterized by periods of heterotopic ossification, often in ligaments. The underlying mechanism is far from clear, partially due to limited access to patient-derived cell models. Periodontal ligament fibroblasts (PLF) from extracted teeth can potentially be used to study deviant bone remodelling processes in vitro since these cells are derived from actual ligaments. They further provid...