Sprouty proteins are modulators of the MAPK/ERK pathway. Amongst these, Sprouty2 (SPRY2) has been investigated as a possible factor that takes part in the initial phases of osteogenesis. However, the in vivo context has not yet been investigated and the underlying mechanisms taking place in vitro remain unknown. Therefore, in this study, the impact of Spry2 deficiency was examined in the developing tibias of Spry2 deficient (-/-) mouse. The investigation was performed when the osteogenic zone became clearly visible and when all three basic bone cells types were present. The main markers of osteoblasts, osteocytes and osteoclasts were evaluated by immunohistochemistry and RT-PCR. RT-PCR showed that the expression of Sost was 3.5 times higher in Spry2-/- than in the wild-type bone, which pointed to a still unknown mechanism of action of SPRY2 on the differentiation of osteocytes. The up-regulation of Sost was independent of Hif-1α expression and could not be related to its positive regulator, Runx2, since none of these factors showed an increased expression in the bone of Spry2-/- mice. Regarding the RANK/RANKL/OPG pathway, the Spry2-/- showed an increased expression of Rank, but no significant change in the expression of Rankl and Opg. Thanks to these results, the impact of Spry2 deletion is shown for the first time in the developing bone as a complex organ including, particularly, an effect on osteoblasts (Runx2) and osteocytes (Sost). This might explain the previously reported decrease in bone formation in postnatal Spry2-/- mice.
- Klíčová slova
- Endochondral bone development, SPROUTY2, growth plate, mouse, ossification,
- MeSH
- buněčná diferenciace MeSH
- cytoplazma metabolismus MeSH
- faktor 1 indukovatelný hypoxií - podjednotka alfa metabolismus MeSH
- ligand RANK metabolismus MeSH
- membránové proteiny genetika fyziologie MeSH
- myši inbrední ICR MeSH
- myši knockoutované MeSH
- myši MeSH
- osteoblasty cytologie metabolismus MeSH
- osteocyty cytologie metabolismus MeSH
- osteogeneze * MeSH
- osteoklasty cytologie metabolismus MeSH
- osteoprotegerin metabolismus MeSH
- proliferace buněk MeSH
- protein-serin-threoninkinasy genetika fyziologie MeSH
- vývoj kostí MeSH
- vývojová regulace genové exprese * MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- faktor 1 indukovatelný hypoxií - podjednotka alfa MeSH
- Hif1a protein, mouse MeSH Prohlížeč
- ligand RANK MeSH
- membránové proteiny MeSH
- osteoprotegerin MeSH
- protein-serin-threoninkinasy MeSH
- Spry2 protein, mouse MeSH Prohlížeč
- Tnfrsf11b protein, mouse MeSH Prohlížeč
- Tnfsf11 protein, mouse MeSH Prohlížeč
There is growing evidence that some members of cytochrome P450 enzymes contribute to regulation of normal prenatal development. CYP epoxygenases (CYP2C and CYP2J subfamilies) convert arachidonic acid into four regioisomeric epoxyeicosatrienoic acids (EETs), biologically active molecules involved in mitogenesis and cell signaling. Almost nothing is known about localization of their expression in tissues during human prenatal development. The spatio-temporal expression pattern of CYP2C8, CYP2C9, CYP2C19 and CYP2J2 in human embryonic/fetal intestines, liver, and kidney was investigated by immunohistochemical method. CYP epoxygenases are expressed already in early stages of development in these embryonic/fetal tissues (as early as 7th week of IUD in the intestines, 5th week of IUD in the liver, and 6th week of IUD in the kidney). In kidney, CYP epoxygenases are expressed in the metanephrogenic blastema (but not in the uninduced mesenchyme) and in the tubular system. In the intestines, diverse CYP epoxygenases distribution along crypt-villus axis could suggest role in cell differentiation. Moreover, we detected higher CYP2J2 level in these organs than in adult tissue samples.
- Klíčová slova
- CYP epoxygenases, human embryos, intestine, kidney, liver,
- MeSH
- časové faktory MeSH
- cytochrom P-450 CYP2J2 MeSH
- cytochrom P450 CYP2C8 genetika MeSH
- embryo savčí enzymologie MeSH
- imunohistochemie MeSH
- játra embryologie enzymologie MeSH
- ledviny embryologie enzymologie MeSH
- lidé embryologie MeSH
- střeva embryologie enzymologie MeSH
- systém (enzymů) cytochromů P-450 genetika metabolismus MeSH
- vývojová regulace genové exprese * MeSH
- Check Tag
- lidé embryologie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- CYP2J2 protein, human MeSH Prohlížeč
- cytochrom P-450 CYP2J2 MeSH
- cytochrom P450 CYP2C8 MeSH
- systém (enzymů) cytochromů P-450 MeSH
