scholarly journals Osteokines and Bone Markers at Rest and following Plyometric Exercise in Pre- and Postmenopausal Women

2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Katlynne Nelson ◽  
Rozalia Kouvelioti ◽  
Alexandros Theocharidis ◽  
Bareket Falk ◽  
Peter Tiidus ◽  
...  

The effect of plyometric exercise on bone biomarkers has been studied in pediatric and young adult populations in order to better understand how exercise influences bone homeostasis. However, there are no such data in postmenopausal women, a group characterized by an uncoupling of the bone resorption-formation cycle. This study examined the serum concentrations of sclerostin, dickkopf-1 (DKK1), c-terminal crosslinking telopeptides of type I collagen (CTXI), and procollagen type I amino-terminal propeptide (PINP) at rest and following a single bout of plyometric exercise in 20 premenopausal ( 23.1 ± 2.3 years) and 20 postmenopausal women ( 57.9 ± 4.3 years). The exercise consisted of 128 jumps, organized into 5 circuit stations. Blood samples were obtained prior to and 5 min, 1 h, and 24 h postexercise. At rest, postmenopausal women had significantly higher sclerostin and CTXI, but lower DKK1 than premenopausal women. Sclerostin increased 5 min postexercise only in the premenopausal group. DKK1 decreased 24 h postexercise in the premenopausal women while it decreased 1 h postexercise in the postmenopausal women. In both groups, CTXI did not change across time and PINP decreased 5 min and 1 h postexercise ( p < 0.05 ). The PINP/CTXI ratio decreased 5 min and 1 h postexercise then significantly increased 24 h postexercise only in premenopausal women. These results indicate that although plyometric exercise is effective in eliciting osteoanabolic effects in younger women; such an effect is not evident in postmenopausal women.

Nutrients ◽  
2019 ◽  
Vol 11 (6) ◽  
pp. 1413
Author(s):  
Manjula Hettiarachchi ◽  
Rachel Cooke ◽  
Catherine Norton ◽  
Phil Jakeman

The diurnal rhythm of bone remodeling suggests nocturnal dietary intervention to be most effective. This study investigated the effect of bedtime ingestion of a calcium-fortified, milk-derived protein matrix (MBPM) or maltodextrin (CON) on acute (0–4 h) blood and 24-h urinary change in biomarkers of bone remodeling in postmenopausal women with osteopenia. In CON, participants received 804 ± 52 mg calcium, 8.2 ± 3.2 µg vitamin D and 1.3 ± 0.2 g/kg BM protein per day. MBPM increased calcium intake to 1679 ± 196 mg, vitamin D to 9.2 ± 3.1 µg and protein to 1.6 ± 0.2 g/kg BM. Serum C-terminal cross-linked telopeptide of type I collagen (CTX) and procollagen type 1 amino-terminal propeptide (P1NP), and urinary N-telopeptide cross-links of type I collagen (NTX), pyridinoline (PYD) and deoxypyridinoline (DPD) was measured. Analyzed by AUC and compared to CON, a −32% lower CTX (p = 0.011, d = 0.83) and 24% (p = 0.52, d = 0.2) increase in P1NP was observed for MBPM. Mean total 24 h NTX excreted in MBPM was −10% (p = 0.035) lower than CON. Urinary PYD and DPD were unaffected by treatment. This study demonstrates the acute effects of bedtime ingestion of a calcium-fortified, milk-based protein matrix on bone remodeling.


1996 ◽  
Vol 42 (10) ◽  
pp. 1639-1644 ◽  
Author(s):  
M Bonde ◽  
C Fledelius ◽  
P Qvist ◽  
C Christiansen

Abstract We present a coated-tube RIA that is useful for assessment of bone resorption. The assay uses a monoclonal antibody raised against a linear 8-amino-acid sequence (EKAHDGGR) derived from the C-telopeptides of type I collagen. Within-run and total CVs were 4.4% and 5.3-6.2%, respectively, at concentrations of 1-7 mg/L (n = 4-20). Analytical recovery was 98% +/- 8% and dilution 97% +/- 7%. Values obtained in a group of 36 premenopausal women were 227 +/- 89.6 mg/mol creatinine. In a group of 141 postmenopausal women, the values obtained were 429 +/- 225 mg/mol creatinine, a highly significant increase of 89% (P &lt;0.001) over the premenopausal value. In a double-blind placebo-controlled clinical study of these postmenopausal women receiving five different doses of a bisphosphonate, a significant decrease of RIA-measured C-telopeptide values was seen in all bisphosphonate-treated groups, after just 3 months. Values in urine samples from postmenopausal women assayed with the RIA (gamma) and the CrossLaps(TM) ELISA (x) agreed well: slope = 0.98 (95% confidence interval, 0.94-1.01), intercept = 0.34 (0.25-0.43) mg/L, and Sylx = 0.93 mg/L (n = 678). We conclude that this RIA represents a valuable tool for assessing bone resorption.


1994 ◽  
Vol 40 (5) ◽  
pp. 811-816 ◽  
Author(s):  
B J Pedersen ◽  
M Bonde

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 &gt; 30 years is 0.36-1.44 nmol/L (geometric mean 0.72 nmol/L, n = 154).


Author(s):  
Patrick Lau ◽  
Åsa Beijer ◽  
André Rosenberger ◽  
Eckhard Schoenau ◽  
Christoph Stephan Clemen ◽  
...  

Acute and protracted effects of resistive exercise (RE) and resistive exercise with whole-body vibration (RVE) on metabolic markers of bone metabolism were investigated. Twenty-six men participated in a randomized training program including RE (n = 13; age = 23.4 ± 1.4 years) or RVE (n = 13; age = 24.3 ± 3.3 years). During the first session, acute C-terminal telopeptide of type I collagen (CTX) responses decreased by 12.9% (standard deviation, SD 13.7%) after 2 min, followed by a 15.5% (SD 36.0%) increase at 75 min after exercise (both p < 0.001). Procollagen type I amino terminal propeptide (P1NP) increased by 12.9% (SD 9.1%) at 2 min (p < 0.001) but no change occurred at 75 min. Sclerostin showed prolonged responses from 2 to 75 min post-exercise in the first session (p < 0.001). Acute responses at the first session were comparable between groups for CTX and P1NP, acute sclerostin responses were substantially greater in RE than in RVE (p = 0.003). No significant differences were noted in the resting baseline levels of CTX, P1NP, or sclerostin from the beginning to the end of the six-week progressive training. The present study therefore did not demonstrate any sizeable enhancement of bone turnover that could match the effects that have been repeatably made in response to countermeasure exercise during bed rest.


2006 ◽  
Vol 91 (3) ◽  
pp. 913-919 ◽  
Author(s):  
H. D. White ◽  
A. M. Ahmad ◽  
B. H. Durham ◽  
S. Chandran ◽  
A. Patwala ◽  
...  

Abstract Context: Patients with active acromegaly have increased bone turnover and skeletal abnormalities. Biochemical cure of acromegaly may represent a functional GH-deficient state and result in cortical bone loss. Reduced PTH target-organ sensitivity occurs in adult GH deficiency and may underlie the associated development of osteoporosis. Objective: We examined the effect of active and treated acromegaly on PTH concentration and target-organ sensitivity. Patients: Ten active acromegalic subjects (GH nadir &gt; 0.3 μg/liter after 75-g oral glucose load and IGF-I above age-related reference range) and 10 matched controls participated in the study. Design: Half-hourly blood and 3-h urine samples were collected on patients and controls for 24 h. Samples were analyzed for PTH, calcium (Ca), nephrogenous cAMP (NcAMP, a marker of PTH renal activity), β C-telopeptide (bone resorption marker), and procollagen type-I amino-terminal propeptide (bone formation marker). Serum calcium was adjusted for albumin (ACa). Eight acromegalic subjects who achieved biochemical cure (GH nadir &lt; 0.3 μg/liter after 75-g oral glucose load and IGF-I within reference range) after standard surgical and/or medical treatment reattended and the protocol repeated. Results: Active acromegalic subjects had higher 24-h mean PTH, NcAMP, ACa, urine Ca, β C-telopeptide, and procollagen type I amino-terminal propeptide (P &lt; 0.05), compared with controls. Twenty-four-hour mean PTH increased (P &lt; 0.001) in the acromegalic subjects after treatment, whereas NcAMP and ACa decreased (P &lt; 0.05). Conclusion: Increased bone turnover associated with active acromegaly may result from increased PTH concentration and action. Biochemical cure of acromegaly results in reduced PTH target-organ sensitivity indicated by increased PTH with decreased NcAMP and ACa concentrations. PTH target-organ sensitivity does not appear to return to normal after successful treatment of acromegaly in the short term and may reflect functional GH deficiency.


2002 ◽  
Vol 87 (7) ◽  
pp. 3324-3329 ◽  
Author(s):  
Jackie A. Clowes ◽  
Robert T. Robinson ◽  
Simon R. Heller ◽  
Richard Eastell ◽  
Aubrey Blumsohn

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.


Author(s):  
W Grant Stevens ◽  
Daniel J Gould ◽  
Linda D Pham ◽  
Joel N Jimenez Lozano

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.


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