Effect of a low-calcium environment on alkaline phosphatase activity in embryonic rat calvarial bone cells in culture

1996 ◽  
Vol 41 (1) ◽  
pp. 41-45 ◽  
Author(s):  
Yoshitaka Yoshimura ◽  
Yoh Hisada ◽  
Kuniaki Suzuki ◽  
Yoshiaki Deyama ◽  
Akira Matsumoto
Keyword(s):  
Alkaline Phosphatase ◽  
Phosphatase Activity ◽  
Alkaline Phosphatase Activity ◽  
Bone Cells ◽  
Calvarial Bone ◽  
Cells In Culture ◽  
Low Calcium

scholarly journals Effect of various media on mineralization and alkaline phosphatase activity in bone cells from embryonic rat calvaria

1995 ◽  
Vol 67 ◽  
pp. 241
Author(s):  
Yoshitaka Yoshimura ◽  
Yoh Hisada ◽  
Kuniaki Suzuki ◽  
Yosbiaki Deyama ◽  
Akira Matsumoto
Keyword(s):  
Alkaline Phosphatase ◽  
Phosphatase Activity ◽  
Alkaline Phosphatase Activity ◽  
Bone Cells ◽  
Rat Calvaria

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 Hypoxia-Induced MicroRNA-429 Promotes Differentiation of MC3T3-E1 Osteoblastic Cells by Mediating ZFPM2 Expression

2016 ◽  
Vol 39 (3) ◽  
pp. 1177-1186 ◽  
Author(s):  
Jiang Huang ◽  
Jianguang Peng ◽  
Guanglei Cao ◽  
Shibao Lu ◽  
Limin Liu ◽  
...  
Keyword(s):  
Alkaline Phosphatase ◽  
Cell Differentiation ◽  
Phosphatase Activity ◽  
Alkaline Phosphatase Activity ◽  
Molecular Mechanisms ◽  
Bone Cells ◽  
Luciferase Reporter ◽  
Valuable Insight ◽  
Matrix Mineralization ◽  
Gene Assay

Background/Aims: Hypoxia has been reported to regulate osteoblastic differentiation of bone cells and cartilage development. However, information concerning the molecular mechanisms remains largely unknown. Methods: The expression of miR-429 was evaluated by quantitative real-time PCR analysis. To test whether miR-429 directly regulate the expression level of ZFPM2 at transcription level, dual-luciferase reporter gene assay was performed. Western blotting was performed to detect osteogenesis related protein expression. The cell proliferation, apoptosis, alkaline phosphatase activity and matrix mineralization were performed to assess the functions of miR-429 in vitro and in vivo the effects of miR-429 on fracture healing. Results: Expression of miR-429 was increased in MC3T3-E1 cells treated with 200 μM CoCl2 by qRT-PCR, and overexpression of miR-429 promoted cell differentiation, and enhanced alkaline phosphatase activity and matrix mineralization. Luciferase reporter assays suggested that miR-429 directly targets the 3'UTR of ZFPM2. In addition, knockdown of ZFPM2 could phenocopy the effects of miR-429 expression. Furthermore, overexpression of ZFPM2 in miR-429-expressing MC3T3-E1 cells suppressed cell differentiation. Conclusions: Our results provide valuable insight into the potential role of hypoxia in regulation of osteoblastic cell differentiation.

Effect of age on intestinal calcium absorption and adaptation to dietary calcium.

1979 ◽  
Vol 236 (6) ◽  
pp. E769 ◽  
Author(s):  
H J Armbrecht ◽  
T V Zenser ◽  
M E Bruns ◽  
B B Davis
Keyword(s):  
Alkaline Phosphatase ◽  
Phosphatase Activity ◽  
Active Transport ◽  
Alkaline Phosphatase Activity ◽  
Calcium Absorption ◽  
Intestinal Adaptation ◽  
Dietary Calcium ◽  
Intestinal Calcium Absorption ◽  
Calcium Diet ◽  
Low Calcium

To study the reported decline in intestinal calcium absorption with age, calcium active transport, immunoreactive calcium protein (CaBP) content, and alkaline phosphatase activity were measured in the intestine of two strains of rats aged 3-wk--20 mo. Calcium active transport, as measured by everted gut sacs from Sprague-Dawley rats, was greatest at 3 wk, but it declined rapidly with no active transport demonstrable at 3 mo or thereafter. CaBP content closely paralleled the decline in active transport, but alkaline phosphatase activity increased as active transport decreased. Intestinal adaptation to dietary calcium was studied by feeding high- and low-calcium diets to Fischer 344 rats aged 1.5--12 mo. In 1.5-mo-old rats fed a low-calcium diet, there was an increase in calcium active transport, CaBP content, and alkaline phosphatase activity relative to animals fed a high-calcium diet. However, the magnitude of this intestinal adaptation decreased with age until there was only marginal adaptation by 12 mo. The observed changes in calcium active transport with age and diet may be explained by the parallel changes in the vitamin D-dependent CaBP content of the intestine.

Sign in / Sign up

Export Citation Format

Share Document