In Vitro Synthesis of Type I Collagen: Quantification of Carboxyterminal Propeptide of Procollagen Type I versus Tritiated Proline Incorporation

1999 ◽  
Vol 64 (3) ◽  
pp. 224-228 ◽  
Author(s):  
M. Nacher ◽  
S. Serrano ◽  
M. L. Mariñoso ◽  
M. C. García ◽  
J. Bosch ◽  
...  
Keyword(s):  
Type I Collagen ◽  
Type I ◽  
In Vitro Synthesis ◽  
Procollagen Type ◽  
Proline Incorporation ◽  
Procollagen Type I

scholarly journals Octreotide Abolishes the Acute Decrease in Bone Turnover in Response to Oral Glucose

2003 ◽  
Vol 88 (10) ◽  
pp. 4867-4873 ◽  
Author(s):  
Jackie A. Clowes ◽  
Heather C. Allen ◽  
Donna M. Prentis ◽  
Richard Eastell ◽  
Aubrey Blumsohn
Keyword(s):  
Bone Turnover ◽  
Bone Turnover Markers ◽  
Type I Collagen ◽  
Gastrointestinal Hormones ◽  
Oral Glucose ◽  
Type I ◽  
Procollagen Type ◽  
Procollagen Type I ◽  
Turnover Markers

Abstract Feeding or oral intake of glucose results in an acute suppression of bone turnover. This does not appear to be mediated by insulin. Several gastrointestinal hormones modulate bone turnover in vitro and may mediate this response. We examined whether inhibiting the production of gastrointestinal hormones using octreotide could block glucose-mediated suppression of bone turnover. Fifteen subjects were each studied on four occasions in a randomized, single-blind, crossover study after receiving 1) oral placebo, iv saline; 2) oral glucose, iv saline; 3) oral glucose, iv octreotide; or 4) iv octreotide alone. We measured serum C-terminal telopeptide of type I collagen, urinary N-terminal telopeptide of type I collagen, osteocalcin, procollagen type I N-terminal propeptide, PTH, insulin, ionized calcium, and glucose over 4 h. All bone turnover markers decreased significantly after oral glucose (P < 0.001). At 120 min serum C-terminal telopeptide decreased by 45 ± 2%, urinary N-terminal telopeptide by 31 ± 7%, osteocalcin by 16 ± 1%, and procollagen type I N-terminal propeptide by 8 ± 1%. There was no significant decrease in bone turnover in response to oral glucose during octreotide infusion. Octreotide alone resulted in a significant increase in all bone turnover markers (P < 0.05) and PTH (P < 0.01). We conclude that octreotide completely abolishes the bone turnover response to glucose intake and increases PTH secretion. The apparent bone turnover response to feeding is probably mediated by an octreotide-inhibitable endocrine factor.

scholarly journals Relative rates of biosynthesis of collagen type I, type V and type VI in calf cornea

1991 ◽  
Vol 274 (2) ◽  
pp. 615-617 ◽  
Author(s):  
P Kern ◽  
M Menasche ◽  
L Robert
Keyword(s):  
Type I Collagen ◽  
Collagen Type ◽  
Corneal Stroma ◽  
Collagen Type I ◽  
Type I ◽  
Type Vi Collagen ◽  
Sds Page ◽  
Proline Incorporation ◽  
Type V

The biosynthesis of type I, type V and type VI collagens was studied by incubation of calf corneas in vitro with [3H]proline as a marker. Pepsin-solubilized collagen types were isolated by salt fractionation and quantified by SDS/PAGE. Expressed as proportions of the total hydroxyproline solubilized, corneal stroma comprised 75% type I, 8% type V and 17% type VI collagen. The rates of [3H]proline incorporation, linear up to 24 h for each collagen type, were highest for type VI collagen and lowest for type I collagen. From pulse-chase experiments, the calculated apparent half-lives for types I, V and VI collagens were 36 h, 10 h and 6 h respectively.

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

In Vitro Synthesis of Normal Bone (Type I) Collagen by Bones of Paget's Disease Patients

1980 ◽  
Vol 163 (4) ◽  
pp. 547-552 ◽  
Author(s):  
H. S. Cheung ◽  
F. R. Singer ◽  
B. Mills ◽  
M. E. Nimni
Keyword(s):  
Type I Collagen ◽  
Paget’S Disease ◽  
Paget's Disease ◽  
Type I ◽  
In Vitro Synthesis ◽  
Normal Bone

scholarly journals Fusion Potential of Human Osteoclasts In Vitro Reflects Age, Menopause, and In Vivo Bone Resorption Levels of Their Donors—A Possible Involvement of DC-STAMP

2020 ◽  
Vol 21 (17) ◽  
pp. 6368
Author(s):  
Anaïs M. J. Møller ◽  
Jean-Marie Delaissé ◽  
Jacob B. Olesen ◽  
Luisa M. Canto ◽  
Silvia R. Rogatto ◽  
...  
Keyword(s):  
Bone Resorption ◽  
Type I Collagen ◽  
Transmembrane Protein ◽  
Type I ◽  
Contributing Factors ◽  
Expression Levels ◽  
Procollagen Type ◽  
Age Related

It is well established that multinucleation is central for osteoclastic bone resorption. However, our knowledge on the mechanisms regulating how many nuclei an osteoclast will have is limited. The objective of this study was to investigate donor-related variations in the fusion potential of in vitro-generated osteoclasts. Therefore, CD14+ monocytes were isolated from 49 healthy female donors. Donor demographics were compared to the in vivo bone biomarker levels and their monocytes’ ability to differentiate into osteoclasts, showing that: (1) C-terminal telopeptide of type I collagen (CTX) and procollagen type I N-terminal propeptide (PINP) levels increase with age, (2) the number of nuclei per osteoclast in vitro increases with age, and (3) there is a positive correlation between the number of nuclei per osteoclast in vitro and CTX levels in vivo. Furthermore, the expression levels of the gene encoding dendritic cell-specific transmembrane protein (DCSTAMP) of osteoclasts in vitro correlated positively with the number of nuclei per osteoclast, CTX levels in vivo, and donor age. Our results furthermore suggest that these changes in gene expression may be mediated through age-related changes in DNA methylation levels. We conclude that both intrinsic factors and age-induced increase in fusion potential of osteoclasts could be contributing factors for the enhanced bone resorption in vivo, possibly caused by increased expression levels of DCSTAMP.

scholarly journals Acute Changes of Bone Turnover and PTH Induced by Insulin and Glucose: Euglycemic and Hypoglycemic Hyperinsulinemic Clamp Studies

2002 ◽  
Vol 87 (7) ◽  
pp. 3324-3329 ◽  
Author(s):  
Jackie A. Clowes ◽  
Robert T. Robinson ◽  
Simon R. Heller ◽  
Richard Eastell ◽  
Aubrey Blumsohn
Keyword(s):  
Bone Turnover ◽  
Type I Collagen ◽  
Oral Glucose ◽  
Type I ◽  
Double Blind ◽  
Euglycemic Clamp ◽  
Procollagen Type ◽  
Procollagen Type I ◽  
Significant Change ◽  
Acute Changes

Bone turnover is acutely suppressed after feeding or oral glucose. Insulin infusion suppresses bone turnover and might mediate this effect, but this is confounded by a possible direct effect of hypoglycemia. We examined the effect of euglycemic hyperinsulinemia and hypoglycemic hyperinsulinemia on bone turnover using an insulin clamp. Sixteen men participated in this double-blind crossover study. Clamp induction involved infusion of insulin (80 mU/m2·min) while maintaining euglycemia (5 mmol/liter) for 40 min with a variable rate dextrose infusion. Glucose was lowered to 2.5 mmol/liter (hypoglycemic clamp) or maintained at 5 mmol/liter (euglycemic clamp) for a further 105 min. Nine controls received a matched saline infusion. Measurements included serum C-terminal telopeptide of type I collagen, procollagen type I N-terminal propeptide, osteocalcin, and PTH. Induction of hyperinsulinemia resulted in a reduction in PTH (27% ± 5; P &lt; 0.01), but no significant change in bone turnover from baseline. Hypoglycemic clamp resulted in suppression of serum C-terminal telopeptide of type I collagen by 34% ± 3, procollagen type I N-terminal propeptide by 15% ± 1, osteocalcin by 5% ± 1, and PTH by a further 12% ± 5 (all P &lt; 0.05). By contrast, there was no significant change in any marker of bone turnover during euglycemic clamp. Postprandial hyperinsulinemia is unlikely to explain the acute suppression of bone turnover with feeding. The reduction in bone turnover during hypoglycemia may be related to hypoglycemia itself, acute changes in PTH, or other hormones released in response to hypoglycemia.

scholarly journals Molecular and Histological Evidence Detailing Clinically Observed Skin Improvement Following Cryolipolysis

2021 ◽  
Author(s):  
W Grant Stevens ◽  
Daniel J Gould ◽  
Linda D Pham ◽  
Joel N Jimenez Lozano
Keyword(s):  
Gene Expression ◽  
Transforming Growth Factor Beta ◽  
Type I Collagen ◽  
Transforming Growth Factor ◽  
Body Contouring ◽  
Fold Increase ◽  
Type I ◽  
Gene Markers ◽  
Procollagen Type ◽  
Procollagen Type I

Abstract Background In addition to body contouring, there is anecdotal and supportive clinical evidence of reduced laxity and skin tightening after cryolipolysis. 10,11 Objectives The nature by which cryolipolysis triggers dermal changes has not been established. This study investigated fundamental mechanisms behind clinically observed dermal changes using molecular and immunohistochemistry methods. Methods This feasibility study involved n=7 subjects that received cryolipolysis treatment. Tissue samples were harvested from 3 days to 5 weeks after treatment. RNA-Sequencing examined differential gene expression of major collagens. RNA In Situ Hybridization (RNA-ISH) investigated the distribution of one of the gene markers for collagen Type I (COL1A1). Immunohistochemistry for Procollagen Type I, heat shock protein 47 (HSP47), transforming growth factor beta (TGF-β and Tropoelastin was performed and quantified. Results Gene expression analysis highlighted a gradual upregulation of collagen mRNA genes. RNA-ISH confirmed upregulation of COL1A1 mRNA and showed a homogenous distribution through the dermis. Immunohistochemistry showed increases in protein expression. Quantification revealed 3.62-fold increase of Procollagen Type I (p&lt;0.0071) and 2.91-fold increase of TGF-β (p&lt;0.041); 1.54-fold increase of HSP47 (p&lt;0.007); and 1.57-fold increase of Tropoelastin (p&lt;0.39) compared to untreated areas. Conclusions This study revealed significant induction of molecular and protein markers of Type I collagen, which supports neocollagenesis and may play an essential role in clinically relevant skin improvement. A dermal remodeling process driven by increased TGF-β and higher expression of HSP47 was observed. Overall, these data provide the first evidence of dermal remodeling and clarify the mechanism by which cryolipolysis may induce skin improvement.

Marked attenuation of production of collagen type I from cardiac fibroblasts by dehydroepiandrosterone

2005 ◽  
Vol 288 (6) ◽  
pp. E1222-E1228 ◽  
Author(s):  
Tomoyuki Iwasaki ◽  
Koji Mukasa ◽  
Masato Yoneda ◽  
Satoshi Ito ◽  
Yoshihiko Yamada ◽  
...  
Keyword(s):  
Mrna Expression ◽  
Collagen Type ◽  
Cardiac Fibroblasts ◽  
Collagen Type I ◽  
Protein Accumulation ◽  
Transcriptional Level ◽  
Type I ◽  
Procollagen Type ◽  
Procollagen Type I

Dehydroepiandrosterone (DHEA) is a type of adrenal steroid. The concentrations of DHEA and its sulfate (DHEA-S) in serum reach a peak between the ages of 25 and 30 yr and thereafter decline steadily. It was reported that DHEA-S concentration in humans is inversely related to death from cardiovascular diseases. In this study, we examined the effects of DHEA on regulation of collagen mRNA and collagen synthesis in cultured cardiac fibroblasts. Treatment with DHEA (10−6 M) resulted in a significant decrease in procollagen type I mRNA expression compared with controls. This was accompanied by a significant decrease in procollagen type I protein accumulation in the medium and also a significant decrease in procollagen type I protein synthesis in the cellular matrix. Furthermore, to confirm in vitro results, we administered DHEA to Sprague-Dawley rats, which were treated with angiotensin II for 8 wk to induce cardiac damage. Procollagen type I mRNA expression was significantly decreased and cardiac fibrosis significantly inhibited in DHEA-treated rat hearts without lowering the systolic blood pressure. These results strongly indicate that DHEA can directly attenuate collagen type I synthesis at the transcriptional level in vivo and in vitro in cardiac fibroblasts.

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