Searchable abstracts of presentations at key conferences on calcified tissues

ba0001pp184 | Cell biology: osteoblasts and bone formation | ECTS2013

Activation of β-catenin signalling enhances the osteogenic gene response to mechanical loading in mesenchymal stem cells

Nemitz Claudia , Jakob Franz , Ignatius Anita , Liedert Astrid

Introduction: Wnt/β-catenin signalling and mechanical loading are able to inhibit adipogenesis and to stimulate osteoblastogenesis of mesenchymal stem cells1,2. The involvement of β-catenin signalling in mechanically induced bone formation has already been shown in vivo using a tibia loading model3. The aim of this study was to investigate the influence of the activation of β-catenin on the osteogenic and adip...

ba0002p8 | (1) | ICCBH2013

Compound heterozygosity of two functional null mutations in the ALPL gene associated with deleterious neurological outcome in an infant with hypophosphatasia

Hofmann Christine , Liese Johannes , Girschick Hermann , Jakob Franz , Mentrup Birgit

Background: Hypophosphatasia (HPP) is a heterogeneous rare, inherited disorder of bone and mineral metabolism caused by different mutations in the ALPL gene encoding the isoenzyme, tissue-nonspecific alkaline phosphatase (TNAP). Prognosis is very poor in severe perinatal forms with most patients dying from pulmonary complications of their skeletal disease. TNAP, a ubiquitous enzyme, is mostly known for its role in bone mineralization. TNAP deficiency, however, may als...

ba0003pp23 | Bone biomechanics and quality | ECTS2014

Influence of estrogen receptor and β-catenin signalling activation on mechanically induced bone formation in ovariectomized mice

Nemitz Claudia , Jakob Franz , Ignatius Anita , Liedert Astrid

Dysfunctions of Wnt/β-catenin and estrogen receptor signalling resulted in impaired mechanotransduction and bone loss as in osteoporosis. Previous studies demonstrated the interaction of these pathways in mechanotransduction in vitro and in vivo. In this study, the influence of the activation of estrogen receptor and β-catenin signalling on mechanically induced bone formation was investigated in ovariectomized mice. 12-week-old mice were ovariectomi...

ba0003pp130 | Cell biology: osteoblasts and bone formation | ECTS2014

Decrease of mineralization by FGF1 is linked to up-regulation of ANKH and OP in osteogenic differentiation and conversion

Simann Meike , LeBlanc Solange , Jakob Franz , Schutze Norbert , Schilling Tatjana

Osteoporosis is generally accompanied by the fatty degeneration of the bone marrow. The enhanced deposition of adipocytes may result from adipogenic differentiation of bone-marrow mesenchymal stem cells (MSC) and from the adipogenic conversion of osteoblastic cells respectively. Thus, whether this clinical observation is a cause of the disease or rather a reaction of the afflicted bone marrow remains to be elucidated.Previous microarray and bioinformatic...

ba0003pp369 | Other diseases of bone and mineral metabolism | ECTS2014

A homozygous 20 bp intronic deletion in front of exon 8 of the ALPL-gene causes infantile hypophosphatasia: a functional characterization

Mentrup Birgit , Girschick Hermann , Jakob Franz , Hofmann Christine

Mutations of the ALPL-gene are closely related to hypophosphatasia (HPP), an inherited disorder of bone and mineral metabolism with clinically heterogeneous symptoms. To date 278 different mutations have been described, leading to reduction or completely loss of enzymatic activity of the tissue nonspecific alkaline phosphatase (TNAP).We present the case of a 6-year-old boy with clinical features and laboratory results consistent with infantile H...

ba0003pp380 | Other diseases of bone and mineral metabolism | ECTS2014

TNSALP influences neurogenic differentiation by altering gene expression in SH-SY5Y cells

Graser Stephanie , Mentrup Birgit , Hofmann Christine , Schneider Doris , Jakob Franz

Hypophosphatasia (HPP) is a rare disease characterized by low enzymatic activity of tissue-nonspecific alkaline phosphatase (TNSALP) resulting in an accumulation of its endogenous substrates like pyridoxal phosphate (PLP) and inorganic pyrophosphate (PPi). The ectoenzyme plays an important role during bone mineralization and might contribute to proper function of kidney and muscle. Neurological symptoms of HPP like seizures, anxiety disorders and depression provide ...

ba0005p89 | Calciotropic and phosphotropic hormones and mineral metabolism | ECTS2016

Endogenous expression and biological functionality of secreted Klotho in human mesenchymal stem cells

Mentrup Birgit , Pauslus Sofia , Krug Melanie , Hafen Bettina , Jakob Franz

The biological relevance of Klotho in aging processes was impressively demonstrated in transgene and knock out mouse experiments and its impact on calcium, vitamin D and phosphate metabolism suggests multifunctional modes of action.The human alpha Klotho gene encodes two transcripts, one for a protein of 130 kDa with a short intracellular and a transmembrane region and the two extracellular domains KL1 and KL2. A second transcript exists due to alternati...

ba0006oc16 | (1) | ICCBH2017

Pediatric hypophosphatasia – a retrospective single-center chart review of 50 children

Vogt Marius , Girschick Hermann Josef , Holl-Wieden Annette , Seefried Lothar , Jakob Franz , Hofmann Christine

Objectives: Hypophosphatasia (HPP) is a rare, inherited metabolic disorder caused by loss-of-function mutations in the ALPL gene that encodes the tissue-nonspecific alkaline phosphatase TNAP (ORPHA 436). Its clinical presentation is highly heterogeneous with a remarkably wide-ranging severity. HPP affects patients of all age. Therefor diagnosis is often difficult and delayed. To improve the understanding of HPP in children and in order to shorten the diagnostic time span in th...

ba0006p057 | (1) | ICCBH2017

Zebrafish as a model for hypophosphatasia

Graser Stephanie , Liedtke Daniel , Geidner Barbara , Heppenstiel Yvonne , Jakob Franz , Klopocki Eva

Objectives: Hypophosphatasia (HPP) is a rare hereditary disease, leading to deficits in bone and tooth mineralization, muscular as well as neurological abnormalities due to decreased enzymatic activity of the tissue-nonspecific alkaline phosphatase (TNAP, encoded by the alpl gene). In this project, the zebrafish (Danio rerio) will be established as a new and valuable animal model for HPP research. Consequently, endogenous TNAP expression should be analyzed in different zebrafi...