scholarly journals Longitudinal in Vivo Analysis of the Region-Specific Efficacy of Parathyroid Hormone in a Rat Cortical Defect Model

Endocrinology ◽  
2008 ◽  
Vol 150 (4) ◽  
pp. 1570-1579 ◽  
Author(s):  
David E. Komatsu ◽  
Kellie A. Brune ◽  
Hong Liu ◽  
Allen L. Schmidt ◽  
Bomie Han ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Bone Healing ◽  
Quantitative Computed Tomography ◽  
Type I ◽  
Defect Model ◽  
Procollagen Type ◽  
Cortical Defect ◽  
Defect Sites ◽  
Procollagen Type I

PTH has been shown to enhance fracture repair; however, exactly when and where PTH acts in this process remains to be elucidated. Therefore, we conducted a longitudinal, region-specific analysis of bone regeneration in mature, osteopenic rats using a cortical defect model. Six-month-old rats were ovariectomized, and allowed to lose bone for 2 months, before being subjected to bilateral 2-mm circular defects in their femoral diaphyses. They were then treated for 5 wk with hPTH1–38 at doses of 0, 3, 10, or 30 μg/kg · d and scanned weekly by in vivo quantitative computed tomography. Quantitative computed tomography analyses showed temporal, dose-dependent increases in mineralization in the defects, intramedullary (IM) spaces, and whole diaphyses at the defect sites. Histomorphometry confirmed PTH stimulation of primarily woven bone in the defects and IM spaces, but not the periosteum. After necropsy, biomechanical testing identified an increase in strength at the highest PTH dose. Serum procollagen type I N-terminal propeptide concentration showed a transient increase due to drilling, but procollagen type I N-terminal propeptide also increased with PTH treatment, whereas tartrate-resistant acid phosphatase unexpectedly decreased. Analyses of lumber vertebra confirmed systemic efficacy of PTH at a nonfracture site. In summary, PTH dose dependently induced new bone formation within defects, at endocortical surfaces, and in IM spaces, resulting in faster and greater bone healing, as well as efficacy at other skeletal sites. The effects of PTH were kinetic, region specific, and most apparent at high doses that may not be entirely clinically relevant; therefore, clinical studies are necessary to clarify the therapeutic utility of PTH in bone healing.

Purification of human procollagen type I carboxyl-terminal propeptide cleaved as in vivo from procollagen and used to calibrate a radioimmunoassay of the propeptide

1994 ◽  
Vol 40 (5) ◽  
pp. 811-816 ◽  
Author(s):  
B J Pedersen ◽  
M Bonde
Keyword(s):  
Geometric Mean ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Type I ◽  
Procollagen Type ◽  
Amino Terminal ◽  
Fetal Fibroblasts ◽  
Procollagen Type I ◽  
Carboxyl Terminal

Abstract We purified human procollagen type I carboxyl-terminal propeptide (PICP) that had been cleaved as in vivo from procollagen. PICP in serum-free medium from cultured human fetal fibroblasts was purified by thiophilic adsorption chromatography, low-pressure gel filtration, and HPLC gel filtration. The purity and homogeneity of the protein was verified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Amino-terminal amino acid sequencing showed that the sequences of the alpha 1 and alpha 2 chains of this PICP were identical to those of the PICP produced in vivo. The monocomponent PICP thus purified was used as calibrator in a simple equilibrium-type RIA of PICP with polyclonal antibodies raised in rabbits. The measuring range is 0.15-3.75 nmol/L, and the assay detection limit is 0.03 nmol/L. The within-run and total CVs are 2% and 4%, respectively. The reference interval for the plasma concentration of PICP in healthy women of ages > 30 years is 0.36-1.44 nmol/L (geometric mean 0.72 nmol/L, n = 154).

Bone Regeneration and Neovascularization Processes in a Pellet Culture System for Periosteal Cells

2009 ◽  
Vol 18 (4) ◽  
pp. 443-452 ◽  
Author(s):  
Mari Akiyama ◽  
Masaaki Nakamura
Keyword(s):  
Ascorbic Acid ◽  
Bone Regeneration ◽  
Nude Mice ◽  
Vascular Endothelial Cells ◽  
Type I ◽  
Vascular Endothelial ◽  
Procollagen Type ◽  
Procollagen Type I ◽  
Periosteal Cells

Reliable bone regeneration can be achieved with a pellet culture system using bovine periosteal cells. However, bone regeneration and neovascularization processes in this system have remained unclear. The present study aimed to clarify the extracellular environment and neovascularization process. To detect components of the extracellular matrix secreted by cells and to identify the conditions necessary for bone regeneration in the body, Western blotting and in vivo tests in nude mice were performed. Cells were cultured with or without ascorbic acid and culture supernatant was precipitated. Western blotting showed that culture supernatant contained collagen type I, procollagen type I, and procollagen type I C-terminus when cells were cultured with ascorbic acid. Cells cultured with ascorbic acid formed partial bony tissues at 2 weeks after grafting to nude mice, while bone formation was missing without ascorbic acid. Immunostaining was performed using species-specific vascular endothelial cell markers to ascertain whether vascular endothelial cells were bovine or murine (nude mouse). Immunohistological methods showed vascular endothelial cells in osseous tissue formed in the subcutaneous tissue of nude mice were murine. Extracellular matrix synthesis in vitro and host blood flow in vivo are essential for bone regeneration.

Abstract 74: The Inflammatory Phenotype Of Mesenchymal Fibroblasts And Its Role In Aging Dependent Cardiac Fibrosis- A Target For Statins?

2014 ◽  
Vol 115 (suppl_1) ◽  
Author(s):  
Katarzyna A Cieslik ◽  
JoAnn Trial ◽  
Mark L Entman
Keyword(s):  
Endothelial Cells ◽  
Myeloid Cell ◽  
Transendothelial Migration ◽  
Mouse Heart ◽  
Type I ◽  
Aged Mouse ◽  
Vitro Assay ◽  
Procollagen Type ◽  
Procollagen Type I ◽  
Inflammatory Phenotype

In the aging mouse (C57BL/6) myocardium fibrosis steadily increases after 14 months of age and is accompanied by elevated numbers of myeloid derived fibroblasts. Recently, we proposed a mechanism by which inflammatory mesenchymal fibroblasts (IMF) derived from mesenchymal stem cells secrete monocyte chemoattractant protein-1 (MCP-1) necessary for myeloid fibroblast induction in the aging heart. The current study extends the characterization of this inflammatory phenotype by describing elevated interleukin-6 (IL-6) secretion and increased expression of IL-6 receptor (IL-6R) in IMF. Since IL-6R lacks an intracellular domain it requires a co-receptor gp130 (generally expressed) to induce an intracellular signal. Thus, generation of an IL-6R soluble receptor allows IL-6 signaling on cells that do not express IL-6R (or expression is low), such as endothelial cells. We investigate the function of IL-6 and IL-6R in the promotion of transendothelial migration of monocytes through cardiac endothelium and their maturation into myeloid fibroblasts in in vitro assay. Treatments with IL-6 and more extensively IL-6+IL-6R resulted in a 3-5 fold increase (above the control level) in myeloid cell migration and maturation into myeloid fibroblasts. Thus IMF can contribute both IL-6 and IL-6R to endothelial cells and facilitate myeloid cell transendothelial migration. In agreement with these data, analysis of the aged mouse heart revealed the presence of fibroblasts expressing IL-6 (procollagen type I + IL-6 + cells), M1 macrophages (CD86 + cells) and M2 macrophages (CD301 + procollagen type I + cells) that were absent in hearts from young mice. The mechanisms by which expression of these factors is upregulated in IMF are being investigated; our data suggest that MCP-1 and IL-6 expression are controlled by the farnesyltransferase (FTase)-Ras-Erk1/2 pathway. Interestingly, since atorvastatin interferes with farnesyl synthesis it also reduced MCP-1 and IL-6 expression in IMF. These data may introduce a new use of this class of drugs in the prevention of the age-related fibrosis.

Effects of fluoride on human bone cells in vitro: differences in responsiveness between stromal osteoblast precursors and mature osteoblasts

1994 ◽  
Vol 130 (4) ◽  
pp. 381-386 ◽  
Author(s):  
Moustapha Kassem ◽  
Leif Mosekilde ◽  
Erik F Eriksen
Keyword(s):  
Bone Marrow ◽  
Alkaline Phosphatase ◽  
Sodium Fluoride ◽  
Bone Cells ◽  
Human Bone ◽  
Type I ◽  
Procollagen Type ◽  
Procollagen Type I ◽  
Osteoblast Precursors

Kassem M, Mosekilde L, Eriksen EF. Effects of fluoride on human bone cells in vitro: differences in responsiveness between stromal osteoblast precursors and mature osteoblasts. Eur J Endocrinol 1994;130:381–6. ISSN 0804–4643 The cellular effects of sodium fluoride (NaF) on human bone cells in vitro have been variable and dependent on the culture system used. Variability could be attributed to differences in responsiveness to NaF among different populations of cells at various stages of differentiation in the osteoblastic lineage. In this study we compared the effects of NaF in serum-free medium on cultures of more differentiated human osteoblast-like (hOB) cells derived from trabecular bone explants and on osteoblast committed precursors derived from human bone marrow, i.e. human marrow stromal osteoblast-like (hMS(OB)) cells. Sodium fluoride (10−5 mol/l) increased proliferation of hMS(OB) cells (p<0.05, N = 10) but was not mitogenic to hOB cells (p>0.05, N= 10). Alkaline phosphatase (AP) production increased in both hMS(OB) (p<0.05, N=9) and hOB cells (p<0.05, N=9). No significant effects on procollagen type I propeptide production were obtained in either culture. In the presence of 1,25-dihydroxycholecalciferol (10−9 mol/l), NaF enhanced alkaline phosphatase (p<0.05, N=8), procollagen type I propeptide (p<0.05, N=7) and osteocalcin (p<0.05, N=7) production by hMS(OB) cells but not by hOB cells. Our results suggest that osteoblast precursors are more sensitive to NaF action than mature osteoblasts and that the in vivo effects of NaF on bone formation may be mediated by stimulating proliferation and differentiation of committed osteoblast precursors in bone marrow. M Kassem, Mayo Clinic, Endocrine Research Unit, W-Joseph 5-164, Rochester, MN 55904, USA

Elevated Procollagen Type I Carboxyterminal Propeptide Production in Cultured Scleroderma Fibroblasts

Dermatology ◽  
1995 ◽  
Vol 190 (2) ◽  
pp. 104-108 ◽  
Author(s):  
K. Kikuchi ◽  
T. Kadono ◽  
M. Fujimoto ◽  
H. Ihn ◽  
S. Sato ◽  
...  
Keyword(s):  
Type I ◽  
Procollagen Type ◽  
Procollagen Type I

Abstract 1957: The Carboxyterminal Telopeptide of Procollagen type I and Procollagen type III Aminoterminal Peptide (PIIINP) are Strong Predictors of Cardiovascular Morbidity and Mortality in the Elderly; The Cardiovascular Health Study

Circulation ◽  
2007 ◽  
Vol 116 (suppl_16) ◽  
Author(s):  
Eddy Barasch ◽  
John S Gottdiener
Keyword(s):  
Prognostic Value ◽  
Cardiovascular Health ◽  
Health Study ◽  
Cardiovascular Health Study ◽  
Type I ◽  
Elderly Individuals ◽  
Procollagen Type ◽  
Procollagen Type I ◽  
Cv Disease ◽  
Carboxyterminal Telopeptide

Background: The fibrillar myocardial extracellular matrix is mainly composed of type I and III fibrillar collagen and their turnover are reflected in the serum level of carboxyl-terminal propeptide type I (PIP) and procollagen type III aminoterminal peptide (PIIINP). The prognostic value of these biomarkers in elderly individuals with heart failure (HF) or other cardiovascular disease (CVD) and in healthy subjects is largely unknown. Aim: To determine the predictive value of PIP, its degradation metabolite, carboxyterminal telopeptide of procollagen type I (CTIP), and PIIINP serum level for the incident CV morbidity and mortality in a nested case control study of community-dwelling elderly individuals enrolled in the Cardiovascular Health Study (CHS). Methods: In 880 participants (ppts) enrolled in the CHS (mean age 77 ± 6 yrs, 52 % males, 79 % white), 310 with HF, 287 controls (no HF but other CVD) and 283 healthy ppts, serum levels of PIIINP, PIP and CTIP were measured by radioimmunoassay. The number of incident CV disease and death were recorded. Wilcoxon rank sum test, Kruskal-Wallis test, and Cox proportional hazards regression were used as appropriate. Results: Age, gender and race and fully adjusted analyses are presented in the table : Conclusions: In this large elderly cohort, there is a strong association between CTIP, PIIINP and incident CVD and death. Elevated CTIP level increases the risk of death more than 50% and of symptomatic PVD by almost two-fold. Whereas PIIINP has a lower predictive power than CTIP, PIP was not associated with incident CVD or death. Serum CTIP and PIIINP have a good prognostic value for both incident CVD and death in elderly individuals with or without known CV disease.

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