Effects of 12 weeks of back-squat training program on jump performances and bone markers in female students

Background:The training program promoted improvements of jump abilities throughout the musculoskeletal system including bone markers.The aim of this study is to examine both the acute and chronic response of bone markers to resistance training program.Methods:Ten female students(age:18±0.7 years,body mass:63±3.6 kg;height:164±5.2 cm)participated in this study.They were recruited for a back-squat training program for 12 weeks,two days/week.The full-back squat protocol consisted of 3–5 sets×3–8 repetitions at 45–55%one repetition maximum.Testing sessions included a 5 jump test(5JT),standing long jump(SLJ),drop jump(DJ),and vertical jump(VJ).Results:Substantial improvements in all testing jumps(5JT:∆10%;P=0.000;ES=1.72;SLJ:∆7%;P=0.000;ES=1.33;DJ:∆11%;P=0.000;ES=0.72;VJ:∆20%;P=0.000;ES=1.84)were found during post program in comparison to pre-program results.Moreover,a significant change(P≤0.05)of bone markers during post-exercise compared to pre-exercise either before or after the training program.Only collagen type I carboxy-terminal peptide(CICP)levels elevated after the training program(pre-exercise only)compared to former levels.Conclusion:12 weeks of back-squat training program resulted greater acute improvements of jump abilities with adaptation in all musculoskeletal system including bone formation.

Calcium-fortified fresh milk ameliorates postmenopausal osteoporosis via regulation of bone metabolism and gut microbiota in ovariectomized rats

The aging of the global population has made postmenopausal osteoporosis prevention essential;however,pharmacological treatments are limited.Herein,we evaluate the effect of calcium-fortified fresh milk(FM)in ameliorating postmenopausal osteoporosis in a rat model established using bilateral ovariectomy.After 3 months of FM(containing vitamin D,and casein phosphopeptides,1000 mg Ca/100 g)or control milk(110 mg Ca/100 g milk)supplementation,bone changes were assessed using dual-energy X-ray absorptiometry,microcomputed tomography,and bone biomechanical testing.The results revealed that FM can regulate bone metabolism and gut microbiota composition,which act on bone metabolism through pathways associated with steroid hormone biosynthesis,relaxin signaling,serotonergic synapse,and unsaturated fatty acid biosynthesis.Furthermore,FM administration significantly increased bone mineral content and density in the lumbar spine and femur,as well as femoral compressive strength,while improving femoral trabecular bone parameters and microarchitecture.Mechanistically,we found that the effects may be due to increased levels of estrogen,bone formation marker osteocalcin,and procollagen typeⅠN-propeptide,and decreased expression of the bone resorption marker C-telopiptide and tartrate-resistant acid phosphatase 5b.Overall,the findings suggest that FM is a potential alternative therapeutic option for ameliorating postmenopausal osteoporosis.

Relationship of serum GDF11 levels with bone mineral density and bone turnover markers in postmenopausal Chinese women

Growth differentiation factor 11 （GDF11） is an important circulating factor that regulates aging. However, the role of GDF11 in bone metabolism remains unclear. The present study was undertaken to investigate the relationship between serum GDF11 level, bone mass, and bone turnover markers in postmenopausal Chinese women. Serum GDF11 level, bone turnover biochemical markers, and bone mineral density （BMD） were determined in 169 postmenopausal Chinese women （47-78 years old）. GDF11 serum levels increased with aging. There were negative correlations between GDF11 and BMD at the various skeletal sites. After adjusting for age and body mass index （BMI）, the correlations remained statistically significant. In the multiple linear stepwise regression analysis, age or years since menopause, BMI, GDF11, and estradiol were independent predictors of BMD. A significant negative correlation between GDF11 and bone alkaline phosphatase （BAP） was identified and remained significant after adjusting for age and BMI. No significant correlation was noted between cross-linked N-telopeptides of type I collagen （NTX） and GDF11. In conclusion, GDF11 is an independent negative predictor of BMD and correlates with a biomarker of bone formation, BAP, in postmenopausal Chinese women. GDF11 potentially exerts a negative effect on bone mass by regulating bone formation.

Correlation of Serum Leptin Level with Bone Mineral Density and Bone Turnover Markers in Chinese Adolescent Dancers

Objective To investigate plasma leptin concentrations in adolescent female dancers and to determine whether leptin has some effects on their bone mineral density （BMD） and bone turnover markers. Methods Sixty dancers aged 15-17 years and 77 healthy controls were enrolled in the study. Bone mineral density （BMD） and body composition were detected by dual energy X-ray absorptiometry. Serum leptin concentrations were measured by radioimmunoassay （RIA）. Two bone turnover markers, bone-specific alkaline phosphatase （BAP） and tartrate-resistant acid phosphatase（TRACP）, were determined by ELISA. Results The dancers had a lower fat mass and a lower leptin level than the controls, while they had a relatively higher BMD of the total body and legs after adjustment for BMI and age. The levels of bone resorption and formation of markers were higher in the dancers than in the controls. Leptin was positively correlated with BMI, body weight, fat mass, and percentage of body fat. In dancers, Leptin was positively correlated with the BMD of the total body and the left leg. However, after adjustment for BMI, no correlation of serum leptin concentrations with BMD values was found in either dancers or controls. Nor correlation was found between leptin and bone turnover markers after adjustment for BMI. Conelusion The leptin profile is different between the controls and the dancers with a lower BMI and a lower fat mass. Circulating plasma leptin level depends on BMI and is not a direct determinant of BMD in Chinese adolescent dancers.

New simulation model for bone formation markers in osteoporosis patients treated with once-weekly teriparatide

Daily 20-mg and once-weekly 56.5-mg teriparatide（parathyroid hormone 1–34） treatment regimens increase bone mineral density（BMD） and prevent fractures, but changes in bone turnover markers differ between the two regimens. The aim of the present study was to explain changes in bone turnover markers using once-weekly teriparatide with a simulation model. Temporary increases in bone formation markers and subsequent decreases were observed during once-weekly teriparatide treatment for 72 weeks. These observations support the hypothesis that repeated weekly teriparatide administration stimulates bone remodeling, replacing old bone with new bone and leading to a reduction in the active remodeling surface. A simulation model was developed based on the iterative remodeling cycle that occurs on residual old bone. An increase in bone formation and a subsequent decrease were observed in the preliminary simulation. For each fitted time point, the predicted value was compared to the absolute values of the bone formation and resorption markers and lumbar BMD. The simulation model strongly matched actual changes in bone turnover markers and BMD. This simulation model indicates increased bone formation marker levels in the early stage and a subsequent decrease. It is therefore concluded that remodeling-based bone formation persisted during the entire treatment period with once-weekly teriparatide.

Effect of Chongcao Bushen Capsule on bone turnover markers in patients with diabetic osteoporosis

Objective:To study the effect of Chongcao Bushen Capsules on bone turnover markers in patients with diabetic osteoporosis.Methods:107 patients with diabetic osteoporosis treated in the Hospital from December 2016 to November 2019were enrolled.They were divided into a control group(n=54)and an observation group(n=53)by random number table.The control group was treated with calcium carbonate,and the observation group was treated with Chongcao Bushen Capsules.The treatment effects,TCM syndrome scores,and bone turnover markers[including osteocalcin,type 1 procollagen amino-terminal propeptide(tP1NP),parathyroid hormone(PTH),25-hydroxyvitamin D,andβ-isomerized c-terminal peptide(β-CTx)],and the incidence of adverse reactions in the two groups were observed and compared.Results:After treatment,the total effective rate of treatment in the observation group(94.44%)was higher than that in the control group(73.58%),and the difference was statistically significant(P<0.05).The scores of symptoms including waist and knee weakness,back and waist pain,lower limb weakness,fatigue and tiredness,difficult walking and dizziness in the observation group were shown to be lower than the control group,and the difference was statistically significant(P<0.05).The levels of osteocalcin,PTH,tP1NP,andβ-CTx in the observation group were lower than those in the control group,and the difference was statistically significant(P<0.05).The 25-hydroxyvitamin D in the observation group was higher than the control group,and the difference was statistically significant(P<0.05).Bone density in both male and female in the observation group was higher than that in the control group,and the difference was statistically significant(P<0.05).Conclusion:For patients with diabetic osteoporosis,Chongcao Bushen Capsule can help improve their clinical symptoms,bone density and the level of bone turnover markers.

The association between the baseline bone resorption marker CTX and incident dysglycemia after 4 years

Bone is an endocrine organ involved in modulating glucose homeostasis. The role of the bone formation marker osteocalcin （OCN） in predicting diabetes was reported, but with conflicting results. No study has explored the association between baseline bone resorption activity and incident diabetes or prediabetes during follow-up. Our objective was to examine the relationship between the baseline bone resorption marker crosslinked C-telopeptide of type I collagen （CTX） and glycemic dysregulation after 4 years. This longitudinal study was conducted in a university teaching hospital. A total of 195 normal glucose tolerant （NGT） women at baseline were invited for follow-up. The incidence of diabetes and prediabetes （collectively defined as dysglycemia） was recorded. A total of 128 individuals completed the 4-year study. The overall conversion rate from NGT to dysglycemia was 31.3%. The incidence of dysglycemia was lowest in the middle tertile [16.3% （95% confidence interval （CI）, 6.8%-30.70/0）] compared with the lower [31.0% （95% CI, 17.2%-46.1%）] and upper [46.5% （95% CI, 31.2%-62.6%）] tertiles of CTX, with a significant difference seen between the middle and upper tertiles （P = 0.002 5）. After adjusting for multiple confounding variables, the upper tertile of baseline CTX was associated with an increased risk of incident dysglycemia, with an odds ratio of 7.09 （95% CI, 1.73-28.99） when the middle tertile was the reference. Osteoclasts actively regulate glucose homeostasis in a biphasic model that moderately enhanced bone resorption marker CTX at baseline provides protective effects against the deterioration of glucose metabolism, whereas an overactive osteoclastic function contributes to an increased risk of subsequent dysglycemia.

Animal Modelling of Lumbar Corpectomy and Fusion and in vivo Growth of Spine Supporting Bone by Titanium Cage Implants: An Experimental Study

In this study a lumbar spinal fusion animal model is established to assess the effect of spinal fusion cage,and explore theminimum area ratio of titanium cage section to vertebral section that ensures bone healing and biomechanical property.Lumbarcorpectomy was conducted by posterolateral approach with titanium cage implantation combined with plate fixation.Titaniumcages with the same length but different diameters were used.After implantation of titanium cages,the progress of bone healingwas observed and the bone biomechanical properties were measured,including deformation and displacement in axial compression,flexion,extension,and lateral bending motion.The factors affecting the in vivo growth of spine supporting body wereanalyzed.The results show that the area ratio of titanium cage section to vertebral section should reach 1/2 to ensure the bonehealing,sufficient bone intensity and biomechanical properties.Some bone healing indicators,such as BMP,suggest that there isa relationship between the peak time and the peak value of bone formation and metabolism markers and the bone healing strength.

Bone Loss in Women with Type 1 Diabetes

Background: Although osteoporosis has been investigated and debated in the diabetic population over the past decades, very little is known about the spontaneous changes in bone mineral density (BMD) and biochemical markers of bone turnover in pre- and postmenopausal type 1 diabetic (T1DM) women over time. Aim: To measure spontaneous changes in BMD and biochemical markers of bone turnover in pre- and postmenopausal T1DM women. Subjects: 53 T1DM women (31 premenopausal and 22 postmenopausal) from the outpatient clinic were enrolled in the study in 1993 and 35 (22 premenopausal, 13 postmenopausal) were reexamined in 1997. Method: BMD was measured at femoral neck (f.n.), spine (L2 - L4), total body and forearm with DXA or SXA in 53 T1DM women. 4 years later a re-scan was carried out on 35 T1DM. Results: In premenopausal subjects a yearly decrease less than 1% at f.n., spine, forearm and total body was observed, though only statistically significant (s.s.) at f.n., p ≤ 0.05. In postmenopausal subjects a s.s. decrease less than 2% was observed at f.n., forearm and total body, p ≤ 0.05. In general, osteopenic or osteoporotic values were observed at the measured skeletal sites. Only at f.n. a lower s.s. BMD compared to age-matched reference women was seen. Conclusion: Small or non-significant changes in BMD and biochemical markers of bone turnover were observed in pre- and postmenopausal T1DM subjects after a 4-year period.

Effect of chronic sleep deprivation on peak bone mass in rats: An experimental study

Objective:To investigate the effects of chronic sleep deprivation(CSD)on bone microstructure and peak bone mass(PBM)in SD rats.Methods:Twenty-four SD rats were randomly divided into CSD group and control group.In the CSD group,a CSD model was established using a new sleep deprivation instrument for rats and mice,and intervened for 5 weeks.Bone turnover markers including P1NP and CTX-1 before and after the experiment were observed.After the experiment,the left femur were scanned by Micro-CT,and the cortical bone and bone trabecula were three-dimensionally reconstructed,respectively.The bone mineral density(BMD)and relevant parameters were detected.Results:CT images of the femur(proximal ends)showed significant trabecular loss in CSD rats.Trabecular parameters including bone volume fraction(BV/TV),trabecular number(Tb.N)and trabecular separation(Tb.Sp)in the CSD group were all lower than those in the control group.The bone cortex of the middle segment of the femur and tibia in CSD rats was also lower than that in the control group.The parameters of bone cortex including total tissue area(Tt.Ar),cortical bone area(Ct.Ar)and cortical bone thickness(Ct.Th)in the CSD group were significantly lower than those in the control group(P<0.01).After chronic CSD,BMD of both bone trabecula and bone cortex of the femur was lower,while the corresponding P1NP and CTX-1 were significantly higher than those in the control group.Conclusion:Sleep plays an important role in PBM formation.CSD accelerates bone turnover and thus significantly reducing PBM in SD rats.

Physiological and pharmacological basis for the ergogenic effects of growth hormone in elite sports

Growth Hormone （GH） is an important and powerful metabolic hormone that is secreted in a pulsatile pattern from cells in the anterior pituitary, influenced by several normal and pathophysiological conditions. Human GH was first isolated in the 1950s and human derived cadaveric GH was initially used to treat patients with GH deficiency. However, synthetic recombinant GH has been widely available since the mid-1980s and the advent of this recombi- nant GH boosted the abuse of GH as a doping agent. Doping with GH is a well-known problem among elite athletes and among people training at gyms, but is forbidden for both medical and ethical reasons. It is mainly the anabolic and, to some extent, the lipolytic effects of GH that is valued by its users. Even though GH＇ s rumour as an effective ergogenic drug among athletes, the effectiveness of GH as a single doping agent has been questioned during the last few years. There is a lack of scientific evidence that GH in supraphysiological doses has additional effects on muscle exercise performance other than those obtained from optimised training and diet itself. However, there might be synergistic effects if GH is combined with, for example, anabolic steroids, and GH seems to have positive effect on collagen synthesis. Regardless of whether or not GH doping is effective, there is a need for a reliable test method to detect GH doping. Several issues have made the development of a method for detecting GH doping complicated but a method has been presented and used in the Olympics in Athens and Turin. A problem with the method used, is the short time span （24-36 hours） from the last GH administration during which the test effectively can reveal doping. Therefore, out-of-competition testing will be crucial. However, work with different approaches to develop an alternative, reliable test is ongoing.

Bone Metabolic Markers in Patients with Obstructive Sleep Apnea Syndrome

Background： Obstructive sleep apnea syndrome （OSAS） is prevalent in obesity and is associated with many metabolic abnormalities. The relationship between OSAS and bone metabolism is still unclear. The aim of this study was to investigate the relationship between the severity of OSAS and bone metabolic markers. Methods： A total of 119 obese males were enrolled in this study in spring months from 2015 to 2017. All candidates underwent polysomnography, and their bone mineral density （BMD） and the serum levels of total procollagen type 1 N-tenninal propeptide （t-P I NP）, N-terminal midfragment ofosteocalcin （N-MID）, [3-C-terminal telopeptide of type 1 collagen （β-CTX）, vitamin D （VD）, and parathyroid hormone （PTH） were measured. The analysis of variance and Pearson correlation analysis were performed for data analyses. Results： No significant differences in the mean values of BMD were observed among the obesity, mild-to-moderate OSAS, and severe OSAS groups; and the serum levels oft-P1NP and [3-CTX in the severe OSAS group were significantly higher than those in the obesity group （48.42 ±23.78 ng/ml vs. 31.98 ± 9.85 ng/ml, P 〈 0.001 ; 0.53 ± 0.24 ng/ml vs. 0.41 ±0.13 ng/ml, P 0.011, respectively）. The serum level of VD in the obesity group was significantly higher than those in the mild-to-moderate and severe OSAS groups （both P 〈 0.001 ）, and decreased as the severity of OSAS increased （P 〈 0.001）. The serum level of PTH in the severe OSAS group was significantly higher than those in the obesity and mild-to-moderate OSAS groups （both P 〈 0.001 ）. The results of correlation analysis indicated that the level of apnea-hypopnea index （AHI） was correlated with the levels oft-P1NP （r = 0.396, P 〈 0.001 ）, VD （r = 0.404, P 〈 0.001 ）, and PTH （r = 0.400, P 〈 0.001 ）, whereas the level of minimum 02 saturation （SaO2min） was correlated with the levels ofVD （r = 0.258, P=0.016） andPTH（r= 0.376, P〈0.001）. Conclusions： The levels of bone resorption and formation markers in patients with severe OSAS were significantly increased compared to obese men, and the severity of OSAS was correlated with the serum levels of t-P1NP, VD, and PTH.

Urine products of bone breakdown as markers of bone resorption and clinical usefulness of urinary hydroxyproline:an overview

Purpose The purpose of this study is to review the urine products of bone breakdown as markers of bone resorption and usefulness of urinary hydroxyproline.Data Related researches published in 1985 -2000 were systematically reviewed.Results Bone markers could be used for early diagnosis of bone metabolic diseases. Biochemical markers of bone resorption that reflect osteoclast activity and/or collagen degradation provide a new and potentially important clinical tool for the assessment and monitoring of bone metabolism. Assessment of bone resorption can be achieved with measurement of urinary hydroxylysine glycosides, urinary excretion of the collagen pyridinium cross-links, urinary excretion of type I collagen telopeptide breakdown products (cross-linked telopeptides) and urinary hydroxyproline.Conclusion Urinary hydroxyproline has been in use as a marker of bone resorption, but it lacks sensitivity and specificity. It is a modified aminoacid that is a metabolic product of collagen breakdown. Hydroxyproline may be released either free or with fragments of the collagen molecule attached during bone resorption, and it is also liberated by the breakdown of complement and nonskeletal collagen.

Effects of a Herbal Formula on Biochemical Markers of Bone Turnover in Ovariectomized Rats

Objective: To investigate the effect and mechanism of a Chinese herbal formula MG in ameliorating estrogen deficiency bone loss. Methods: 10 month old female rats were randomly divided into three groups: ovariectomized (OVX), OVX treated with MG decoction (OVX M) and OVX treated with estrogen injection (OVX E). The urinary pyridinoline creatinine ratio (Pyd/Cr), deoxypyridinoline creatinine ratio (Dpd/Cr), and plasma alkaline phosphatase (ALP) were determined at the baseline, 1, 4, 8 and 12 postoperative weeks. Results: Our data showed an average increase of 93% in Pyd/Cr ( P <0.001), 180% in Dpd/Cr ( P <0.005) and 59% in plasma ALP ( P <0.001) respectively in the OVX group after ovariectomy. Compared with OVX rats, the increase of the OVX M group were prevented 39% in Pyd/Cr, 102% in Dpd/Cr and 19% in ALP respectively ( P <0.05). Conclusion: The herbal formula MG possesses a therapeutic effect on estrogen dependent bone loss by inhibiting the bone turnover as estrogen replacement.

Correlations of single photon emission computed tomography joints scan and bone metabolic markers in active rheumatoid arthritis

Objective To explore the correlation between quantitative value of joint bone scan by single photon emission computed tomography(SPECT)and serum bone metabolic markers in patients with active rheumatoid arthritis(RA).Methods Clinical data of 60 newly diagnosed RA patients were retrospectively collected in Department

Effects of raloxifene hydrochloride on bone mineral density, bone metabolism and serum lipids in Chinese postmenopausal women with osteoporosis: a multi-center, randomized, placebo-controlled clinical trial

Background Raloxifene has been approved for prevention and treatment of postmenopausal osteoporosis in Caucasian women. It also has some positive effects on serum lipids in Caucasians. The objective of this study was to determine the effect of raloxifene hydrochloride on lumbar spine and total hip bone mineral density (BMD), bone metabolism, and serum lipids in Chinese postmenopausal women with osteoporosis.Methods This was a multi-center, randomized, double-blind, placebo-controlled clinical trial in which 204 postmenopausal Chinese women with osteoporosis were assigned to receive raloxifene (60 mg) or placebo treatment daily for 12 months. BMD, serum bone metabolism markers, and serum lipids were measured before and after drug administration. BMD was measured by Dual-Energy X-Ray Absorptiometry (DEXA) and bone metabolism markers were analyzed by one-step enzyme-linked immunosorbent assay. Serum lipids were measured by enzymatic analysis.Results At the end of the 12-month study, lumbar spine BMD increased in both groups with a mean increase of (3.3±4.8) % in the raloxifene group and (1.0±4.9) % in the placebo group (P<0.001). There was a mean increase in total hip BMD of (1.4±4.8) % in the raloxifene group and a mean decrease of (0.9±5.0) % in the placebo group (P<0.001). No subject in the raloxifene group had a new vertebral fracture and 5 placebo subjects had new fractures (P>0.05). In the raloxifene group, the median decreases in the biochemical markers of bone metabolism serum osteocalcin and C-telopeptide were 41.7% and 61.5%, respectively. These changes were statistically significant compared with those in the placebo group (10.6% and 35.6%, P<0.001, respectively). Both total cholesterol and low-density lipoprotein cholesterol decreased significantly in the raloxifene group compared with those in the placebo group (P<0.001, respectively) and there was no significant effect of raloxifene on high-density lipoprotein cholesterol and triglycerides compared with placebo. Conclusions Raloxifene 60 mg/d for 12 months significantly increases lumbar spine and total hip BMD, significantly decreases bone turnover, and has favourable effects on serum lipids in Chinese postmenopausal women with osteoporosis.

Urinary cross-linked N-telopeptides of type Ⅰ collagen and bone metabolic diseases

Objective To evaluate the type I collagen cross linked N telopeptide (NTx) levels in human urine as an indicator of bone resorption rate in different ages, sex and in bone metabolic diseases.Methods Urinary NTx was determined by immunoassay in 591 Beijing healthy subjects aged from 0 to 86 years and 379 patients with bone metabolic diseases.Results The levels of urinary NTx were significantly higher in children than in adults (P<0.001) and higher in boys than in girls (P<0.01) and increased 1.4-2.2 times in postmenopausal females than in men and premenopausal women. Urine NTx had a positive linear correlation with urine HOP/Cr (r= 0.778, P< 0.01) and Ca/Cr ratio (r=0.320, P< 0.01 ), and a negative linear correlation with age (r= -0.523, P<0.01) and lumbar spine BMD (r= -0.426, P<0.01). The levels of urine NTx increased for 3.6 times in pregnancy, 1.5 times in osteoporosis, 1.9 times in fragility fracture, 3.6 times in chronic renal failure, 2.1 times in rickets and 7.2 times in multiple myeloma compared to age matched controls.Conclusions NTx in urine is a specific and sensitive indicator of bone resorption and is able to distingish normal premenopause from late osteoporotic patients. NTx could be used as diagnostic information about metabolic bone diseases, and to monitor antiresorptive therapy.

Clinical update of pulsed electromagnetic fields on osteoporosis

Objective To understand the effects of low-frequency pulsed electromagnetic fields （PEMFs） on chronic bony pain, bone mineral density （BMD）, bone strength and biochemical markers of bone metabolism in the patients of osteoporosis. Data sources Using the key words “pulsed electromagnetic fields” and “osteoporosis”, we searched the PubMed for related studies published in English from January 1996 to December 2007. We also searched the China National Knowledge Infrastructure （CNKI） for studies published in Chinese from January 1996 to December 2007.Study selection Inclusion criteria： （1） all articles which referred to the effects of low-frequency pulsed magnetic fields on osteoporosis either in primary osteoporosis or secondary osteoporosis; （2） either observational studies or randomized controlled studies. Exclusion criteria： （1） articles on experimental studies about osteoporosis; （2） repetitive studies; （3） case reports; （4） meta analysis.Results Totally 111 related articles were collected, 101 of them were published in Chinese, 10 were in English. Thirty-four were included and the remaining 84 were excluded.Conclusions Low-frequency PEMFs relieves the pain of primary osteoporosis quickly and efficiently, enhances bone formation and increases BMD of secondary osteoporosis. But the effects of PEMFs on bone mineral density of primary osteoporosis and bone resorption were controversial.