Searchable abstracts of presentations at key conferences on calcified tissues

ba0003pp190 | Genetics | ECTS2014

Premature aging of bone is delayed by dietary restriction

van der Eerden Bram , Botter Sander , Reiling Erwin , Hoeijmakers Jan , Dolle Martijn , van Leeuwen Johannes

Loss of genomic maintenance contributes to aging, as exemplified by mutations in Ercc DNA repair proteins that lead to a plethora of progeroid syndromes of which some display accelerated bone loss. It is generally accepted that dietary restriction (DR) increases life span and improves organ function. We therefore assessed the impact of DR on life span and bone mass in WT and bona fide prematurely aging hypomorphic Ercc-deficient mice (Ercc1−/Δ).<...

ba0005p158 | Cell biology: osteoblasts and bone formation | ECTS2016

A single 2-day pulse of activin-A leads to a transient change in gene expression eventually followed by reduction in extracellular matrix mineralization

Baroncelli Marta , Drabek Ksenija , Eijken Marco , Peppel Jeroen van de , van Leeuwen Johannes

Activins belong to the transforming growth factor-β superfamily, and they regulate bone formation by controlling both osteoclast and osteoblast behaviour. We have previously shown that activin-A strongly inhibited matrix mineralization in osteoblast cultures, and that activin A-signalling was most effective before the onset of mineralization.The aim of this study was therefore to investigate how an early activin-A pulse affected osteoblast mineraliz...

ba0005p61 | Bone development/growth and fracture repair | ECTS2016

Advanced phase gestational jet lag reduces bone mass of adult offspring

van der Eerden Bram , Chaves Ines , Azimzadeh Pedram , Schreuders-Koedam Marijke , Reiss Irwin , van Leeuwen Johannes , van der Horst Gijsbertus

The mammalian circadian clock is tightly controlled by clock genes, which have been shown to regulate up to 20% of the transcriptome in any given tissue. Evidence is accumulating that light-modulation perpetually affects circadian clock performance. In accordance, shift work or chronic jet lag is associated with higher risk of disease later in life, including osteoporosis. In this study, we assessed whether gestational jet lag in mice reduces bone mass postnatally.<p class...

ba0005p83 | Bone Matrix | ECTS2016

Cortical bone matrix mineralisation is decreased in TRPV4 deficient male, but not in female mice

Roschger Paul , Misof Barbara , Fratzl-Zelman Nadja , Hoenderop Joost , Bindels Rene , van Leeuwen Johannes , Klaushofer Klaus , van der Eerden Bram

Transient receptor potential vanilloid channels (TRPVs) have been implicated in Ca2+ homeostasis and bone metabolism. In particular, TRPV4 deficiency was shown to cause sexual dimorphism in bone metabolism and osteoporotic fracture risk. Cortical bone structure was reported to be altered in male TRPV4 knock-out (TRPV4−/−) mice but not in female TRPV−/− mice compared to sex-matched wildtype (TRPV4+/+) animals.To gain knowledge on t...

ba0002p44 | (1) | ICCBH2013

A homozygous mutation in the DNA binding domain of human vitamin D receptor causes vitamin D resistant rickets

van der Eerden Bram , van der Heyden Josine , Hamburger Jan Piet , Schreuders-Koedam Marijke , Asmawidjaja Patrick , de Muinck Keizer-Schrama Sabine , Lubberts Erik , van Leeuwen Johannes , Drop Stenvert

In this case report, we present a brother and sister with hereditary vitamin D resistant rickets (HVDRR). Both children presented at the age of 18 months with severe rickets and elevated serum levels of 1,25-(OH)2D3. They differ from each other in that the girl presented with hypophosphatemia instead of hypocalcemia. Besides, she developed alopecia earlier than the boy and needed more 1,25-(OH)2D3 supplementation. Interestingly, the ...