P57. Cultured cells from the growing tip of deer antler express alkaline phosphatase activity and synthesise type I collagen

Bone ◽  
1994 ◽  
Vol 15 (1) ◽  
pp. 130 ◽  
Author(s):  
JS Price ◽  
A Frazer ◽  
BO Oyajobi ◽  
RGG Russell
Keyword(s):  
Alkaline Phosphatase ◽  
Phosphatase Activity ◽  
Alkaline Phosphatase Activity ◽  
Type I Collagen ◽  
Cultured Cells ◽  
Type I ◽  
Deer Antler

scholarly journals Cytocompatibility evaluation of hydroxyapatite/collagen composites doped with Zn+2

2007 ◽  
Vol 12 (2) ◽  
pp. 307-312 ◽  
Author(s):  
Maria Helena Santos ◽  
Ana Paula M. Shaimberg ◽  
Patricia Valerio ◽  
Alfredo M. Goes ◽  
Maria de Fátima Leite ◽  
...  
Keyword(s):  
Alkaline Phosphatase ◽  
Phosphatase Activity ◽  
Alkaline Phosphatase Activity ◽  
Orthophosphoric Acid ◽  
Type I Collagen ◽  
Enzymatic Digestion ◽  
Osteoblastic Cells ◽  
Type I ◽  
Post Test ◽  
Synthetic Hydroxyapatite

The cytocompatibility of synthetic hydroxyapatite/collagen composites alone or doped with Zn+2 was tested by using primary culture of osteoblasts. The hydroxyapatite (HAP) was synthesized having calcium hydroxide and orthophosphoric acid as precursors. A new HAP composite was developed adding 1.05 w% of Zn(NO3)2.6H2O forming HAPZn. The pure type I collagen (COL) was obtained from bovine pericardium by enzymatic digestion method. The HAP/COL and HAPZn/COL composites were developed and characterized by SEM/EDS. The cell viability and alkaline phosphatase activity in the presence of composites were evaluated by MTT assay and NBT-BCIP assay, respectively, and compared to osteoblastic cells of the control. Three individual experiments were accomplished in triplicates and submitted to the variance analysis and Bonferroni’s post-test with statistically significant at p<0.05. The HAPZn/COL composite did not stimulate the proliferation and increasing of alkaline phosphatase activity of the osteoblastic cells. The tested composites did not alter the cellular viability neither caused alterations in the cellular morphology in 72 h showing adequate properties for biological applications.

Effects of transforming growth factor-β on normal clonal bone cell populations

1991 ◽  
Vol 69 (2-3) ◽  
pp. 132-140 ◽  
Author(s):  
Rebecca Ber ◽  
Takao Kubota ◽  
Jaro Sodek ◽  
Jane E. Aubin
Keyword(s):  
Alkaline Phosphatase ◽  
Growth Factor ◽  
Phosphatase Activity ◽  
Alkaline Phosphatase Activity ◽  
Transforming Growth Factor ◽  
Bone Cells ◽  
Transforming Growth Factor Β ◽  
Prostaglandin E ◽  
Intracellular Camp ◽  
Type I

Although transforming growth factor-β (TGF-β) has been implicated in the local regulation of bone growth and remodelling, its specific effects on different subpopulations of bone cells have not been elucidated. Cells derived from bone are known to be heterogeneous and include both cells of different lineages and osteoblastic populations with different levels of expression of osteoblast-associated properties. Consequently, we have isolated clonal populations of bone cells to examine more precisely the effects of TGF-β on individual subpopulations. Several clonal populations were isolated by limiting dilution from cells derived from 21-day-old fetal rat calvaria. Two of these clones, RCA 11 and RCB 2, were used here. While the two clones responded similarly to parathyroid hormone (PTH) and isoproterenol (ISP) with increases in intracellular cAMP, prostaglandin E2 (PGE2) elicited a 10-fold higher response in RCB 2 cells compared with RCA 11. RCB 2 cells expressed a 10-fold higher alkaline phosphatase activity compared with RCA 11. Both clones synthesized a variety of bone matrix associated proteins, but only RCA 11 synthesized SPP-1 (osteopontin) constitutively. TGF-β stimulated growth of RCB 2 cells after 24 and 48 h of treatment, but had no effect on growth of RCA 11. TGF-β supported anchorage-independent growth of RCB 2 cells, but not that of RCA 11. A 24-h exposure to TGF-β decreased cAMP responsiveness to PTH and ISP slightly in both clones, but had no effect on PGE2 responses. Significant reductions in alkaline phosphatase activity were seen in both clones after 24- and 48-h treatments with TGF-β. Total protein synthesis as measured by [35S]methionine incorporation was stimulated significantly in both clones, but TGF-β selectively stimulated type I collagen compared with type III collagen. SPARC (osteonectin) and secreted phosphoprotein 1 (SPP-1; osteopontin) were stimulated by TGF-β in both RCA 11 and RCB 2 cells. These results indicate that individual clonal populations of cells within bone may be modulated differentially by TGF-β.Key words: transforming growth factor-β, osteoblasts, clonal cell lines, matrix synthesis.

scholarly journals Modulation of connexin43 alters expression of osteoblastic differentiation markers

2006 ◽  
Vol 290 (4) ◽  
pp. C1248-C1255 ◽  
Author(s):  
Zhongyong Li ◽  
Zhiyi Zhou ◽  
Marnie M. Saunders ◽  
Henry J. Donahue
Keyword(s):  
Alkaline Phosphatase ◽  
Phosphatase Activity ◽  
Alkaline Phosphatase Activity ◽  
Intercellular Communication ◽  
Cell Communication ◽  
Osteoblastic Differentiation ◽  
Type I ◽  
Mrna Levels ◽  
Gap Junctional Intercellular Communication ◽  
Gap Junctional

Gap junctional channels between cells provide a pathway for exchange of regulatory ions and small molecules. We previously demonstrated that expression of connexins and cell-to-cell communication parallel osteoblastic differentiation and that nonspecific pharmacological inhibitors of gap junctional communication inhibit alkaline phosphatase activity. In this study, we stably transfected connexin (Cx)43 antisense cDNA into the immortalized human fetal osteoblastic cell line hFOB 1.19 (hFOB/Cx43−). hFOB/Cx43− cells express lower levels of Cx43 protein and mRNA and display a 50% decrease in gap junctional intercellular communication relative to control [hFOB/plasmid vector control (pvc)]. This suggests that other connexins, such as Cx45, which is expressed to a similar degree in hFOB/Cx43− cells and hFOB/pvc cells, contribute to cell-to-cell communication in hFOB 1.19 cells. We observed almost total inhibition of alkaline phosphatase activity in hFOB/Cx43− cells despite only a 50% decrease in cell-to-cell communication. This suggests the intriguing possibility that Cx43 expression per se, independent of cell-to-cell communication, influences alkaline phosphatase activity and perhaps bone cell differentiation. Quantitative real-time RT-PCR revealed that mRNA levels for osteocalcin and core binding factor α1 (Cbfa1) increased as a function of time in hFOB/pvc but were inhibited in hFOB/Cx43−. Osteopontin mRNA levels were increased in hFOB/Cx43− relative to hFOB/pvc and decreased as a function of time in both hFOB/Cx43− and hFOB/pvc. Transfection with Cx43 antisense did not affect expression of type I collagen in hFOB 1.19 cells. These results suggest that gap junctional intercellular communication and expression of Cx43 contribute to alkaline phosphatase activity, as well as osteocalcin, osteopontin, and Cbfa1 expression in osteoblastic cells.

scholarly journals Anti-Osteoporotic Effects of Antioxidant Peptides PIISVYWK and FSVVPSPK from Mytilus edulis on Ovariectomized Mice

Antioxidants ◽  
2020 ◽  
Vol 9 (9) ◽  
pp. 866 ◽  
Author(s):  
Yunok Oh ◽  
Chang-Bum Ahn ◽  
Won Ho Cho ◽  
Na Young Yoon ◽  
Jae-Young Je
Keyword(s):  
Alkaline Phosphatase ◽  
Phosphatase Activity ◽  
Signaling Pathway ◽  
Alkaline Phosphatase Activity ◽  
Bmp Signaling ◽  
Type I ◽  
Antioxidant Peptides ◽  
Mineral Density ◽  
Food Ingredients ◽  
Ovariectomized Mice

Numerous amounts of evidence suggest that bioactive peptides with diverse physiological activities can be nutraceuticals or potential drug candidates. In this study, blue mussel-derived antioxidant peptides PIISVYWK and FSVVPSPK were subjected to evaluate their osteogenic effect in mouse bone marrow mesenchymal stem cells (mBMMSCs) followed by an in vivo anti-osteoporotic effect. Treatment of PIISVYWK and FSVVPSPK on mBMMSCs stimulated alkaline phosphatase activity and calcification. Western blot results revealed that PIISVYWK and FSVVPSPK increased the expression of bone morphogenetic protein-2/4 (BMP-2/4) followed by upregulating p-Smad1/5, type I collagen, and transcription factors including Runx2 and osterix in mBMMSCs. Two peptides also activated the phosphorylation of MAPKs (p-p38, p-ERK, and p-JNK). Treatment of MAPK inhibitors significantly inhibited the BMP signaling pathway, indicating that PIISVYWK and FSVVPSPK stimulated osteoblast differentiation of mBMMSCs through the MAPK-dependent BMP signaling pathway. The anti-osteoporotic effect of PIISVYWK and FSVVPSPK in ovariectomized (OVX) mice was investigated. Treatment of PIISVYWK and FSVVPSPK for ten weeks showed a notable anti-osteoporotic effect in OVX mice via increasing bone mineral density and other bone parameters compared to OVX mice without peptides. Serum analysis also showed that treatment of PIISVYWK and FSVVPSPK completely reduced osteocalcin and ALP (alkAline phosphatase) activity. Taken together, these results suggest that PIISVYWK and FSVVPSPK could be health-promoting functional food ingredients against osteoporosis.

scholarly journals Roles of Bone Morphogenetic Protein Type I Receptors and Smad Proteins in Osteoblast and Chondroblast Differentiation

1999 ◽  
Vol 10 (11) ◽  
pp. 3801-3813 ◽  
Author(s):  
Makiko Fujii ◽  
Kohsuke Takeda ◽  
Takeshi Imamura ◽  
Hiromasa Aoki ◽  
T. Kuber Sampath ◽  
...  
Keyword(s):  
Alkaline Phosphatase ◽  
Bone Morphogenetic Protein ◽  
Phosphatase Activity ◽  
Alkaline Phosphatase Activity ◽  
Chondrogenic Differentiation ◽  
C2c12 Cells ◽  
Vector System ◽  
Type I ◽  
Morphogenetic Protein ◽  
Smad Proteins

The biological effects of type I serine/threonine kinase receptors and Smad proteins were examined using an adenovirus-based vector system. Constitutively active forms of bone morphogenetic protein (BMP) type I receptors (BMPR-IA and BMPR-IB; BMPR-I group) and those of activin receptor–like kinase (ALK)-1 and ALK-2 (ALK-1 group) induced alkaline phosphatase activity in C2C12 cells. Receptor-regulated Smads (R-Smads) that act in the BMP pathways, such as Smad1 and Smad5, also induced the alkaline phosphatase activity in C2C12 cells. BMP-6 dramatically enhanced alkaline phosphatase activity induced by Smad1 or Smad5, probably because of the nuclear translocation of R-Smads triggered by the ligand. Inhibitory Smads, i.e., Smad6 and Smad7, repressed the alkaline phosphatase activity induced by BMP-6 or the type I receptors. Chondrogenic differentiation of ATDC5 cells was induced by the receptors of the BMPR-I group but not by those of the ALK-1 group. However, kinase-inactive forms of the receptors of the ALK-1 and BMPR-I groups blocked chondrogenic differentiation. Although R-Smads failed to induce cartilage nodule formation, inhibitory Smads blocked it. Osteoblast differentiation induced by BMPs is thus mediated mainly via the Smad-signaling pathway, whereas chondrogenic differentiation may be transmitted by Smad-dependent and independent pathways.

Synergistic effects of different bone morphogenetic protein type I receptors on alkaline phosphatase induction

2001 ◽  
Vol 114 (8) ◽  
pp. 1483-1489 ◽  
Author(s):  
H. Aoki ◽  
M. Fujii ◽  
T. Imamura ◽  
K. Yagi ◽  
K. Takehara ◽  
...  
Keyword(s):  
Alkaline Phosphatase ◽  
Phosphatase Activity ◽  
Alkaline Phosphatase Activity ◽  
Osteoblast Differentiation ◽  
Transforming Growth Factor ◽  
Nuclear Translocation ◽  
Synergistic Effects ◽  
Transforming Growth Factor Β ◽  
C2c12 Cells ◽  
Type I

Bone morphogenetic proteins (BMPs) are members of the transforming growth factor-(β) superfamily, which regulate the differentiation of osteoprogenitor cells. Here we show that among members of the BMP family, BMP-4 and growth/differentiation factor 5 (GDF-5) induce osteoblast differentiation through the activation of three receptor-regulated Smads (i.e. Smad1, Smad5 and Smad8). By contrast, BMP-6 and BMP-7 induce alkaline phosphatase activity through Smad1 and Smad5, but not through Smad8. Consistent with these findings, BMP-4 induced phosphorylation and nuclear translocation of Smad1, Smad5 and Smad8, but BMP-6 activated only Smad1 and Smad5. BMP-4 and GDF-5 are known to bind to activin receptor-like kinase 3 (ALK-3) and/or ALK-6 (also termed BMP type IA and type IB receptors, respectively), whereas BMP-6 and BMP-7 preferentially bind to ALK-2. Compared with the effects induced by only one of the type I receptors, the combination of constitutively active forms of ALK-2 and ALK-3 (or ALK-6) more strongly induced alkaline phosphatase activity in C2C12 cells. Moreover, addition of BMP-4 and BMP-6 to C2C12 cells resulted in higher alkaline phosphatase activity than that of only one of these BMPs. The combination of ALK-2 and ALK-3 also induced higher transcriptional activity than either receptor alone. Thus, ALK-2 and ALK-3 (or ALK-6) might synergistically induce osteoblast differentiation of C2C12 cells, possibly through efficient activation of downstream signaling pathways.

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