Ajwa date flavonoids mitigate neutrophil migration and interferon-γ-induced renal injury by ultraviolet C radiation in rats

Date was considered a high nutritional value fruit due to its high content of active ingredients. Frequent exposure to cosmetic radiations including UVC caused deleterious effects and tissue damage and organ affection. This study investigated the efficacy of Ajwa date extract (ADE) in protection against UVC-induced kidney injury in rats. Five groups of rats were included in this study. Group I: Rats were exposed to UVC radiation at a dose 5 kJ (1 h/day) for 28 days. Group II: Rats were pretreated orally with ADE (10 mg/kg/day) 1 h before exposure to UVC radiation with dose 5 kJ. Group III: Rats were pretreated with ADE (15 mg/kg) 1 h before exposure to UVC radiation. Group IV: Rats were exposed to UVC radiation then treated with ADE (10 mg/kg). Group V: Rats exposed to UV radiation then treated with ADE (15 mg/kg) after 1 h from exposure. Analyzing the active constituents of ADE by GC/MS showed that, quercetin, myricetin kaempferol, thymine, and catechol are the most active ingredients. Biochemical markers obtained showed that, serum 8-oxoguanine as marker for DNA damage was increased, and total antioxidant activity and glutathione reduced were decreased (p < 0.01), while neutrophil (p < 0.001), conjugated diene (p < 0.05), and interferon-γ (p < 0.01) were increased after exposure to UVC. However, all the parameters changed were reversed by ADE-treated rats compared with untreated; the higher dose was more effective and protective effect was better than treated effect. Kidney total proteins and reduced glutathione and procollagen levels were decreased while malondialdehyde was increased after exposure to UVC (p < 0.01). These abnormalities were normalized by ADE treatment and protected. It was concluded that, flavonoids from Ajwa extract protected against deleterious effects of UVC by enhancing antioxidant activities and reducing infiltration of neutrophils that caused kidney injury.

Effect of the traditional Chinese herb Helminthostachys zeylanica on postsurgical recovery in patients with ankle fracture: A double-blinded randomized controlled clinical trial

ETHNOPHARMACOLOGICAL RELEVANCE

Helminthostachys zeylanica (HZ), which is also called "Dao-Di-U-Gon" in Taiwan, has anti-inflammatory and antiedema effects and is commonly used to treat edema in patients with fractures. The ugonin K component of HZ can induce osteogenesis and promote bone mineralization, its therapeutic effect, however, its therapeutic effect remains unclear. Therefore, the purpose of the present study was to investigate the effect of HZ on functional recovery in patients with ankle fractures requiring surgical treatment.

METHODS

A double-blinded, randomized, controlled study was conducted. A total of 45 patients with ankle fractures requiring surgical treatment were assigned to either the control group (n = 23 patients), which received the oral administration of HZ placebo 1.0 g t.i.d. for 42 days continuously, or to the treatment group (22 patients), which received HZ for 42 days.

RESULTS

The serum amino-terminal propeptide of type 1 procollagen (PINP) levels were similar in the first assessment (V1) between the control (45.90 ± 16.31 ng/mL) and treatment groups (52.61 ± 21.02 ng/mL; p = 0.240); the differences in PINP level between the third assessment (V3) and V1 were greater in the treatment group (35.84 ± 24.56 ng/mL) than in the control group (16.34 ± 11.97 ng/mL; p = 0.002). Radiographic healing time (RHT) was 9.09 ± 1.15 weeks in the treatment group, which was shorter than the 9.91 ± 0.79 weeks (p = 0.012) in the control group.

CONCLUSION

Oral administration of HZ for 42 days can increase serum PINP level and reduce the RHT. Therefore, HZ can be used to treat patients with ankle fractures requiring surgical treatment. However, a larger sample size is needed in future studies.

Positive association of glucagon with bone turnover markers in type 2 diabetes: A cross-sectional study

AIMS

The osteo-metabolic changes in type 2 diabetes (T2D) patients are intricate and have not been fully revealed. It is not clear whether glucagon is entirely harmful in the pathogenesis of diabetes or a possible endocrine counter-regulation mechanism to reverse some abnormal bone metabolism. This study aimed to investigate the association between glucagon and bone turnover markers (BTMs) in T2D patients.

METHODS

A total of 3984 T2D participants were involved in a cross-sectional study in Shanghai, China. Serum glucagon was measured to elucidate its associations with intact N-terminal propeptide of type I collagen (P1NP), osteocalcin (OC), and β-C-terminal telopeptide (β-CTX). Glucagon was detected with a radioimmunoassay. Propeptide of type I collagen, OC, and β-CTX were detected using chemiluminescence. The diagnosis of T2D was based on American Diabetes Association criteria.

RESULTS

The concentration of glucagon was positively correlated with two BTMs [OC-β: 0.034, 95% CI: 0.004, 0.051, p = 0.024; CTX-β: 0.035, 95% CI: 0.004, 0.062, p = 0.024]. The result of P1NP was [P1NP-regression coefficient (β): 0.027, 95% CI: -0.003, 0.049, p = 0.083]. In the glucagon tertiles, P for trend of the BTMs is [P1NP: 0.031; OC: 0.038; CTX: 0.020], respectively.

CONCLUSIONS

Glucagon had a positive effect on bone metabolism. The concentrations of the three BTMs increased as glucagon concentrations rose. This implied that glucagon might speed up skeletal remodelling, accelerate osteogenesis, and promote the formation of mature bone tissue. At the same time, the osteoclastic process was also accelerated, providing raw materials for osteogenesis to preserve the dynamic balance. In view of the successful use of single-molecule as well as dual/triple agonists, it would be feasible to develop a preparation that would reduce osteoporosis in diabetic patients.

Diagnostic value of HA, PC-III, IV-C, and LN in infants with congenital biliary atresia

Hyaluronic acid (HA), type III procollagen III (PC-III), type IV collagen IV (IV-C), and laminin (LN) have certain diagnostic value for hepatobiliary diseases. No published studies have compared the diagnostic accuracy of these 4 indicators for the diagnosis of congenital biliary atresia (CBA) in infants. This study aimed to investigate the diagnostic value of HA, PC-III, IV-C, and LN in infants with CBA. From January 2017 to December 2020, 185 infants with nonphysiological jaundice in the Second Department of General Surgery at the Children's Hospital of Hebei were enrolled in this study. Forty-six infants with CBA (CBA group) and 139 infants without CBA (noncongenital biliary atresia group) were diagnosed using ultrasonography, magnetic resonance imaging, intraoperative exploration, and intraoperative cholangiography. The levels of HA, PC-III, IV-C, and LN in the 2 groups were statistically analyzed. The diagnostic accuracy was determined using receiver operating characteristic curves and by calculating the area under the curve. Univariate and multivariate logistic regression analyses were performed to identify the independent risk factors. Compared to the noncongenital biliary atresia group, the levels of HA, PC-III, IV-C, and LN were significantly increased in the CBA group (P <.05). The receiver operating characteristic analysis showed the optimal cutoff values for HA, PC-III, IV-C, and LN were 162.7, 42.5, 199.7, and 101.2 ng/mL, and the area under the curves were 0.892, 0.762, 0.804, and 0.768, respectively. The sensitivity values for the diagnosis of CBA were 76.82%, 71.61%, 70.32%, and 72.28%, and the specificity values for the diagnosis of biliary atresia were 70.22%, 70.44%, 66.34%, and 68.71%, respectively. In the multivariate model, HA ≥162.7 ng/mL (odds ratio [OR] = 5.28, 95% confidence interval [CI]: 3.15-8.37), PC-III ≥42.5 ng/mL (OR = 4.61, 95% CI: 2.54-7.16), IV-C ≥199.7 ng/mL (OR = 5.02, 95% CI: 2.98-7.64), and LN ≥101.2 ng/mL (OR = 6.25, 95% CI: 2.41-10.07) remained associated with the occurrence of CBA. HA, PC-III, IV-C, and LN have high accuracy for the diagnosis of CBA in infants, and these factors are potential diagnostic biomarkers for CBA.

The relationship between estimated glucose disposal rate and bone turnover markers in type 2 diabetes mellitus

PURPOSE

To investigate the relationship between estimated glucose disposal rate (eGDR) and bone turnover markers in patients with type 2 diabetes mellitus (T2DM).

MATERIALS AND METHODS

This is a cross-sectional study, which recruited 549 patients with T2DM. The eGDRs of patients were calculated based on the presence of hypertension, glycated hemoglobin, and body mass index. All patients were divided into high-eGDR group and low-eGDR group using the median of eGDR as the boundary. The patients were further divided into two subgroups: males and postmenopausal females.

RESULTS

The lower the eGDR, the more severe was insulin resistance. The levels of osteocalcin (OC), type I collagen carboxyl-terminal peptide (β-CTX), and type I procollagen amino-terminal peptide (PINP) were significantly lower in the low-eGDR group than those in the high-eGDR group. The eGDR was positively correlated with OC, β-CTX, and PINP in all patients, and in the male subgroups. In the postmenopausal female subgroup, there was no correlation between eGDR and OC, β-CTX, or PINP. In addition, this positive correlation remained after adjusting for other factors in multilinear regression analysis.

CONCLUSION

Our study was the first to demonstrate that eGDR is positively correlated with bone turnover markers in patients with T2DM. This correlation was observed among the male patients with T2DM but not among postmenopausal female patients with T2DM.

FSH may mediate the association between HbA1c and bone turnover markers in postmenopausal women with type 2 diabetes

INTRODUCTION

Recent studies in postmenopausal women have found associations of follicle-stimulating hormone (FSH) levels with both glucose metabolism and bone turnover. The objective of the study was to investigate whether FSH may contribute to suppressed bone turnover markers (BTMs) in postmenopausal women with type 2 diabetes (T2D).

MATERIALS AND METHODS

888 postmenopausal women with T2D, 352 nondiabetes (prediabetes plus normoglycemia) were included from the METAL study. HbA1c, sex hormones, 25-hydroxy vitamin D (25(OH)D), serum procollagen type I N-terminal propeptide (P1NP), and β-C-terminal telopeptide (β-CTX) were measured.

RESULTS

P1NP and β-CTX decreased in postmenopausal T2D women compared with nondiabetes controls (both p < 0.001). The major factors responsible for the changes in P1NP were HbA1c (β = - 0.050, p < 0.001), 25(OH)D (β = - 0.003, p = 0.006), FSH (β = 0.001, p = 0.044) and metformin (β = - 0.109, p < 0.001), for β-CTX were HbA1c (β = - 0.049, p < 0.001), body mass index (BMI) (β = - 0.011, p = 0.005), 25(OH)D (β = - 0.003, p = 0.003), FSH (β = 0.002, p = 0.022) and metformin (β = - 0.091, p = 0.001) in postmenopausal T2D women based on multivariate regression analysis. With the increase in HbA1c, FSH decreased significantly (p for trend < 0.001). Mediation analysis demonstrated that FSH partly mediated the suppression of LnP1NP and Lnβ-CTX by HbA1c (β = - 0.009 and - 0.010, respectively), and Lnβ-CTX by BMI (β = - 0.015) when multiple confounders were considered (all p < 0.05).

CONCLUSION

HbA1c was the crucial determinant contributing to the suppression of BTMs. FSH might play a novel mediation role in BTM suppression due to HbA1c or BMI.

Plasma EBF1 as a Novel Biomarker for Postmenopausal Osteoporosis

Postmenopausal osteoporosis (OPO) is one of the most common types of primary osteoporosis. There is currently lack of a plasma biomarker for sensitive and early diagnosis of OPO. Here we aimed to explore the potential of early B cell factor 1 (EBF1) as a new plasma biomarker of OPO. Quantitative real-time PCR was used to measure the plasma EBF1 levels. Absorptiometry markers, such as lumbar spine (LS) bone mineral density (BMD) and LS T score were obtained after X-ray scans. Biochemical analyses used to measure osteopontin (OPN), β-isomerized C-terminal telopeptides and total N-terminal procollagen of type-I collagen levels of patients with osteopenia (OPE, n = 81), osteoporosis (OPO, n = 98) as well as healthy subjects (NC, n = 110). Quantitative real-time PCR was used to measure the plasma levels of PAX5 and GSTP1, which are target genes of EBF1. EBF1 was downregulated in OPO patients. Levels of EBF1 were positively correlated to clinicopathological characteristics, including LS BMD and LS T scores, and negatively correlated to OPN and total N-terminal procollagen of type-I collagen levels. Increased PAX5 and GSTP1 levels also demonstrated strong correlations with higher EBF1, LS BMD and LS T score. Anti-osteoporotic treatment resulted in significant upregulation of EBF1, PAX5 and GSTP1 at 6 mo after treatment. Our study suggests that plasma EBF1 is a potential biomarker for diagnosing and assessing treatment outcome of OPO.

Novel serological biomarker models composed of bone turnover markers, vitamin D, and estradiol and their auxiliary diagnostic value in girls with idiopathic central precocious puberty

OBJECTIVE

To establish serological biomarker models composed of bone turnover markers (BTMs), vitamin D (Vit D), and estradiol (E2) and to explore their auxiliary diagnostic value in girls with idiopathic central precocious puberty (ICPP).

METHODS

Ninety-three girls with ICPP and 93 healthy girls were included in the ICPP group and the control group, respectively. The serum levels of total procollagen type 1 N-terminal propeptide (P1NP), N-terminal midfragment of osteocalcin (N-MID), β-C-terminal telopeptide of type 1 collagen (β-CTX), Vit D, E2, and other biochemical parameters were detected in all participants. Serological biomarker models for assistance with ICPP diagnosis were established by logistic regression analyses.

RESULTS

Serum P1NP, β-CTX, Vit D, and E2 levels differed significantly between the two groups (p < 0.05). Three models were established. Model 1 consisted of P1NP and β-CTX, and had an area under curve (AUC) of 0.764, sensitivity of 74.19%, and specificity of 72.04%. Model 2 consisted of P1NP, β-CTX, and Vit D, and had an AUC of 0.840, sensitivity of 83.87%, and specificity of 72.04%. Model 3 consisted of P1NP, β-CTX, Vit D, and E2, and had an AUC of 0.917, sensitivity of 82.80%, and specificity of 86.02%.

CONCLUSIONS

Serum P1NP, β-CTX, Vit D, and E2 levels may be effective indicators for auxiliary diagnosis of ICPP. Serological biomarker models composed of P1NP, β-CTX, Vit D, and E2 (models 1, 2, and 3) may have auxiliary diagnostic value for ICPP.

Undercarboxylated Osteocalcin and Its Associations With Bone Mineral Density, Bone Turnover Markers, and Prevalence of Osteopenia and Osteoporosis in Chinese Population: A Cross-Sectional Study

OBJECTIVE

Undercarboxylated osteocalcin (ucOC) is one form of osteocalcin lacking full carboxylation, which plays an important role in bone homeostasis, glucose homeostasis, and energy metabolism. Our aim is to obtain the profile of serum ucOC level according to gender and age and explore its associations with bone mineral density (BMD), bone turnover markers (BTMs), and prevalence of osteopenia and osteoporosis in the Chinese population.

METHODS

This is a cross-sectional study with 900 subjects, composed of 431 men and 469 women. Clinical information was collected, and BMD values of the lumbar spine (L1-4), left femoral neck, and total hip were scanned. Biochemical markers including hepatic and renal function, serum calcium, serum phosphorus, procollagen type 1 N-propeptide (P1NP) β-CrossLaps of type I collagen-containing cross-linked C-telopeptide (β-CTX) intact parathyroid hormone (PTH), 25-hydroxyvitamin D (25OHD), and ucOC were measured.

RESULTS

We found that the median ucOC level was higher in men than women [men, 2.6 ng/ml; women, 1.6 ng/ml; p < 0.001]. The profile according to age showed that ucOC levels were the lowest at the age of 40-49 years in both men [2.55 ng/ml (95% CI = 1.96-3.13 ng/ml)] and women [1.57 ng/ml (95% CI = 1.12-2.03 ng/ml)]; in patients younger than 49 years, they decreased with age; then over 50 years, they quickly increased. Furthermore, we found that a higher ucOC level was correlated with lower BMD values at the lumbar spine (men, r = -0.128, p = 0.013; women, r = -0.321, p < 0.001), femoral neck (men, r = -0.095, p = 0.062; women, r = -0.260, p < 0.001), and total hip (men, r = -0.123, p = 0.015; women, r = -0.209, p < 0.001) and higher P1NP (men, r = 0.307, p < 0.001; women, r = 0.239, p < 0.001) and β-CTX (men, r = 0.169, p = 0.001; women, r = 0.354, p < 0.001) levels in both men and women. Furthermore, we also showed that a 1 - SD increase in ucOC was associated with an odds ratio (OR) of 1.63 and 1.70 for having osteopenia or osteoporosis in men and women, respectively (men, 95% CI = 1.25-2.13, p = 0.004; women, 95% CI = 1.19-2.42, p = 0.004).

CONCLUSIONS

We first revealed the profile of serum ucOC levels according to gender and age in the Chinese population and demonstrated the associations of ucOC with BMD and BTMs and the risk of prevalent osteopenia or osteoporosis. Our findings provide a clue to elucidate the function of ucOC in bone metabolism.

Acute Effects of Strength and Endurance Training on Bone Turnover Markers in Young Adults and Elderly Men

CONTEXT

Exercise is recognized as an important strategy to prevent bone loss, but its acute effects on bone turnover markers (BTMs) and related markers remain uncertain.

OBJECTIVE

To assess the acute effects of two different exercise modes on BTMs and related markers in young adults of both sexes and elderly men.

DESIGN SETTING PARTICIPANTS

This was a three-group crossover within-subjects design study with a total of 53 participants-19 young women (aged 22-30), 20 young men (aged 21-30 years), and 14 elderly men (aged 63-74 years)-performing two different exercise sessions [strength training (ST) and high-intensity interval training (HIIT)] separated by 2 weeks, in a supervised laboratory setting.

MAIN OUTCOME MEASURES

Plasma volume-corrected serum measurements of the BTMs C-terminal telopeptide of type 1 collagen (CTX-I) and procollagen of type 1 N-terminal propeptide (P1NP), total osteocalcin (OC), sclerostin, and lipocalin-2 (LCN2) at baseline, immediately after, and 3 and 24 h after each of the two exercise modes were performed.

RESULTS AND CONCLUSION

Analyses revealed sex- and age-dependent differences in BTMs and related bone markers at baseline and time-, sex-, and age-dependent differences in response to exercise. No differences between exercise modes were observed for BTM response except for sclerostin in young men and LCN2 in elderly men. An acute, transient, and uniform increase in P1NP/CTX-1 ratio was found in young participants, demonstrating that beneficial skeletal effects on bone metabolism can be attained through both aerobic endurance and resistance exercise, although this effect seems to be attenuated with age. The acute effects of exercise on bone-related biomarkers were generally blunted after 24 h, suggesting that persistent alterations following prolonged exercise interventions should be assessed at later time points.

The Positive Relationship Between the Low-Density Lipoprotein Cholesterol/Apoprotein B Ratio and Bone Turnover Markers in Patients With Type 2 Diabetes

BACKGROUND

Dyslipidemia may contribute to low bone turnover in patients with type 2 diabetes (T2D) through mediating oxidative stress and atherosclerosis. The low-density lipoprotein cholesterol/apoprotein B (LDL-C/Apo B) ratio is a surrogate marker of small and density low-density lipoprotein cholesterol (sd-LDL-C), a most harmful group of LDL-Cs. The present study aimed to investigate the association between the LDL-C/Apo B ratio and bone turnover in patients with T2D.

METHODS

This study was a cross-sectional study enrolled patients with T2D from January 2021 to December 2021. Each participant was assessed for lipid profiles, bone turnover markers (BTMs), lumbar spine (L1-L4) and hip dual-energy X-ray absorptiometry (DXA) scans. Osteoporosis was diagnosed as a T-score lower than or equal to -2.5 at the spine or hip.

RESULTS

A total of 335 patients with T2D were enrolled in the study, and the LDL-C/Apo B ratio ranged from 0.78 to 4.00. Along with the LDL-C/Apo B ratio tertile ascending, osteocalcin (OC), C-terminal telopeptide (CTx) and N-terminal propeptide of type-I procollagen (PINP) levels gradually increased (all p < 0.05). There were no differences in lumbar spine and hip T-score, proportion of osteoporosis (all p > 0.05) among the three subgroups. The LDL-C/Apo B ratio was positively correlated with lnOC (r = 0.244, p < 0.001), lnCTx (r = 0.226, p < 0.01) and lnPINP (r = 0.211, p < 0.001). These significant positive correlations persisted even when divided into male and female subgroups. Furthermore, three multiple linear regression analyses were constructed to investigate the independent association of the LDL-C/Apo B ratio with the BTMs levels. After adjusting for other clinical parameters, the LDL-C/Apo B ratio was still significantly associated with OC level (β = 0.199, t = 3.348, p < 0.01), CTx level (β = 0.238, t = 4.084, p < 0.001) and PINP level (β = 0.162, t = 2.741, p < 0.01).

CONCLUSION

The LDL-C/Apo B ratio was significantly and positively associated with BTMs in patients with T2D. In clinical practice, more attention should be paid to the patients with T2D whose LDL-C/Apo B ratio is relatively low for the purpose of maintaining bone health.

Analysis of serum bone turnover markers in female cynomolgus monkeys of different ages

OBJECTIVE

The purpose of this study was to examine bone turnover markers, estradiol, parathyroid hormone, and 25 hydroxyvitamin D, in cynomolgus monkeys at different ages to improve our understanding of the changes in bone turnover markers throughout the life cycle of cynomolgus monkeys and to provide a basis for the establishment of a non-human primate model of osteoporosis.

METHODS

Total Body Bone Mineral Density and Total Body Bone Mineral Content were measured using Dual-Energy X-Ray Absorptiometry in cynomolgus monkeys at different ages. Serum bone turnover marker' levels were measured using enzyme immunoassays at each age group, and the relationship between bone turnover markers and age was assessed by Spearman rank correlation analysis to investigate the relationship between bone turnover markers and age in female cynomolgus monkeys.

RESULTS

Total Body Bone Mineral Density in female cynomolgus monkeys peaked at 10 years of age and then formed a plateau that was maintained until old age. Procollagen I Aminoterminal Propeptide, Bone Alkaline Phosphatase, Osteocalcin, and C-Terminal Telopeptide Of Type I Collagen peaked at 1 to 3 years of age and gradually decreased with age, leveling off by 10 years of age. Estradiol, parathyroid hormone, and 25 hydroxyvitamin D, follicle-stimulating hormone, luteinizing hormone, were not significantly different among age groups.

CONCLUSION

This paper provides data on trends in bone turnover markers throughout the life cycle of female cynomolgus monkeys, which are similar to human changes.

Glucose variability and low bone turnover in people with type 2 diabetes

INTRODUCTION

Type 2 diabetes (T2D) is related to an increased fracture risk and low bone turnover. However, the mechanisms are not elucidated. In the present study we investigate the association between glycemic variability and bone turnover markers.

METHODS

100 participants with T2D and 100 age and gender matched controls were included in this cross-sectional study. All participants with T2D were equipped with a continuous glucose monitoring (CGM) sensor for 3 days (CGMS iPro Continuous Glucose Recorder; Medtronic MiniMed). The dawn glucose levels were defined as a morning period starting 1 h before breakfast ending 1 h post ingestion. On all participants serum (s)-C-terminal cross-linked telopeptide of type-I collagen (CTX), s-procollagen type 1 amino terminal propeptide (P1NP), and s-sclerostin were measured.

RESULTS

Participants with T2D displayed significantly lower levels of the bone resorption marker s-CTX and the bone formation marker s-P1NP compared to controls. S-CTX was significantly negatively associated with the mean amplitude of glycemic excursions (MAGE) and the dawn glucose levels whereas s-P1NP only was significantly negatively associated with the dawn glucose levels while it was borderline significantly associated with MAGE (p = 0.05). S-CTX and s-P1NP were significantly lower among the 50% with the highest dawn glucose levels compared to the 50% lowest dawn glucose levels also after adjustment for age, gender, glycated hemoglobin A1c (HbA1c), and body mass index (BMI).

CONCLUSION

We observed that the amplitude of glycemic excursions and rise in dawn glucose was negatively associated with bone turnover markers. Future research is needed to determine whether reduction of the amplitude of glycemic excursions increase bone turnover markers.

3-Hydroxybutyrate administration elevates plasma parathyroid hormone in a pilot human randomized, controlled, cross over trial

CONTENT

Ketone bodies, in particular 3-hydroxybutyrate (3OHB), are known to possess important energetic and signaling capacities. There is a growing block of evidence, that ketogenic dieting (KD), fasting, and sodium glucose transporter 2 inhibitor (SGLT2i) treatment are associated with hyperparathyroidism and negative bone health.

OBJECTIVE

We aimed to study the effect of exogenous 3OHB administration on bone metabolism, specifically the effect on parathyroid hormone (PTH) and calcium/phosphate homeostasis.

DESIGN

A randomized, controlled, cross over study with two arms: i) saline infusion and ii) 3OHB infusion.

SETTING

The study was conducted at Aarhus University Hospital.

PARTICIPANTS

We examined eight healthy human subjects aged 50-70 years.

INTERVENTION

Continuous intravenous DL-3OHB-NaCl infusion or 0.9% NaCl was administered for 390 min.

MAIN OUTCOME MEASURES

The study was designed to test the impact of 3OHB on PTH, calcium-phosphate, C-terminal Telopeptide (CTX), and Procollagen I N-terminal Propeptide (PINP). The study was a post hoc study.

RESULTS

The PTH concentration increased by 25% with a concomitant drop in phosphate of 30% in the 3OHB group. 3OHB infusion increased concentrations of CTX by 5%, without changes in PINP and albumin corrected calcium concentrations.

CONCLUSION

In conclusion, 3OHB administration increases PTH concentration and markers of bone resorption. These findings suggest a possible negative effect on bone health, which needs to be determined in future studies.

Exome sequencing identifies procollagen-lysine 2-oxoglutarate 5-dioxygenase 2 mutations in primary congenital and juvenile glaucoma

PURPOSE

To report the association of procollagen-lysine 2-oxoglutarate 5-dioxygenase 2 (PLOD2) mutations with bilateral primary congenital glaucoma (PCG) in monozygotic twins and with nondominant juvenile-onset primary open-angle glaucoma (JOAG).

METHODS

We utilized family-based whole-exome sequencing to detect disease-causing mutations in a pair of monozygotic twins with de-novo PCG and compared its existence in 50 nonfamilial cases of JOAG and 30 healthy controls. To validate the identified mutations, direct Sanger sequencing was performed. For further evaluation of gene expression in the ocular tissues, we performed whole-mount in situ hybridization in zebrafish embryos.

RESULTS

We identified a novel missense mutation (c.1925A>G, p.Tyr642Cys) in the PLOD2 gene in the monozygotic twin pair with PCG and another missense mutation (c.1880G>A, p.Arg627Gln) in one JOAG patient. Both mutations identified were heterozygous. Neither the parents of the twins nor the parents of the JOAG patient harbored the mutation and it was probably a de-novo change. The zebrafish in situ hybridization revealed expression of the PLOD2 gene during embryogenesis of the eye.

CONCLUSION

We observed an association of PLOD2 mutations with PCG and with nonfamilial JOAG. This new gene needs to be further investigated for its role in pathways associated with glaucoma pathogenesis.

The Development of Novel N-Terminal Pro-Peptide of Type I Chemiluminescence Assay

BACKGROUND

P1NP can be used for monitoring patients treated with both bisphosphonates and teriparatide as bone formation markers. P1NP assays include two types, intact trimeric form of P1NP assay and total P1NP assay. In this study we provided another type of P1NP assay.

METHODS

The α-1 chain was constructed as recombined P1NP protein in the Corynebacterium glutamicum gene expression system. Native proteins were purified from Hydrothorax. Antibody clones were screened using mice immune to the α-1 chain peptide. The screened antibody was used for assay development. Assay performance was verified and afterwards the method comparison was analyzed between the self-developed assay and Roche P1NP assay.

RESULTS

α-1 chain and native P1NP proteins were purified and used for antibody selection and making the calibrator. Three clones of antibody were screened and 2 of them were used in the assay development. The assay performance was characterized, including the linearity, precision, and sensitivity. Method comparison was also performed between our assay and Roche P1NP assay showing a 0.98 slope.

CONCLUSIONS

A new P1NP assay was provided that recognizes only the α-1 chain and, thus, may provide more insight for disease monitoring when the P1NP assay is applied in clinic in the future.

Bone metabolism subgroups identified as hip fracture patients via clustering

PURPOSE

The aim of the study was to describe the bone metabolism status that underlies a hip fracture.

METHODS

Estimated glomerular filtration rate (e-GFR), calcium (Ca), phosphorus (P), total (ALP) and bone specific alkaline phosphatase (b-ALP), intact parathyroid hormone (i-PTH), 25-hydroxy-vitamin D (25OHD), total procollagen type I amino-terminal propeptide (PINP), and N-terminal peptide of collagen I (NTx), measured at admission in 272 hip fracture patients, were ex post analyzed by K-means clustering and principal component analysis and were evaluated by a clinician.

RESULTS

Four components, mainly consisting of b-ALP, PINP, ALP, and NTx; e-GFR and P; i-PTH and 25OHD; and Ca explained about 70% of the variability. A total of 184 patients clustered around a centroid (A) with low 25OHD (13.2 ng/ml), well-preserved kidney function (e-GFR=67.19 ml/min/1.73m²), normal Ca, P, i-PTH and bone markers, with the exception of slightly increased NTx (24.82nMBCE). Cluster B (n=70) had increased i-PTH (93.38 pg/ml), moderately decreased e-GFR, very low 25OHD (8.68 ng/dl), and high bone turnover (b-ALP 28.46 U/L, PINP 69.87 ng/ml, NTx 31.3nMBCE). Cluster C (n=17) also had hyperparathyroidism (80.35 pg/ml) and hypovitaminosis D (9.15 ng/ml), low e-GFR(48.89 ml/min/1.73m²), and notably high ALP (173 U/L) and bone markers (b-ALP 44.64 U/L, PINP 186.98 ng/ml, NTx 38.28nMBCE). According to the clinician, 62 cases clearly had secondary hyperparathyroidism.

CONCLUSIONS

Based on serum measurements, the dominant patterns of bone metabolism were normal bone turnover with high normal NTx, and secondary hyperparathyroidism related to chronic kidney disease and hypovitaminosis D. The bone formation markers, e-GFR, NTx, and P composed the most important factors.

Reference intervals in Danish children and adolescents for bone turnover markers carboxy-terminal cross-linked telopeptide of type I collagen (β-CTX), pro-collagen type I N-terminal propeptide (PINP), osteocalcin (OC) and bone-specific alkaline phosphatase (bone ALP)

PURPOSE

Bone turnover markers (BTM) are gaining ground in clinical practice but to fully use their potential there is a need for establishing valid reference intervals (RI). Consequently, the purpose of the study was to establish general RI as well as suggested clinical RI for carboxy-terminal cross-linked telopeptide of type I collagen (β-CTX), pro-collagen type I N-terminal propeptide (PINP), osteocalcin (OC) and bone-specific alkaline phosphatase (bone ALP) in children and adolescents.

METHOD

BTM were measured on Danish children and adolescents participating in the CHAMPS-study DK. A total of 762 participants were included (8-18 years, 50.4% girls) contributing a total of 1410 study visits. The RI was calculated based on 2-years age spans. Participants with biochemical signs of metabolic bone disease were excluded.

RESULTS

The differences in RI between age groups clearly reflect changes in growth with an initial increase in BTM, greatest in boys, and a subsequent decrease most pronounced in girls. β-CTX and PINP are markers most affected by these changes, compared to OC and bone ALP. The suggested clinical 95% RI included participants with vitamin D insufficiency but no biochemical signs of metabolic bone disease which did not markedly alter the RI.

CONCLUSION

RI for β-CTX, PINP, OC and bone ALP varies with age and sex. β-CTX and PINP which reflect bone resorption and formation processes are mostly affected by these changes. We suggest a set of clinically applicable 95% RI for the four BTM to heighten the usefulness and generalizability of the RI.

The effects of acute hyponatraemia on bone turnover in patients with subarachnoid haemorrhage: A preliminary report

CONTEXT

Animal data and cross-sectional human studies have established that chronic hyponatraemia predisposes to osteoporosis; the effects of acute hyponatraemia on bone turnover have not been determined. Our objective was to test the hypothesis that acute hyponatraemia leads to dynamic effects on bone turnover.

DESIGN

A prospective observational pilot study.

METHODS

Bone turnover markers [C-terminal crosslinking telopeptide of type 1 collagen (CTX-1), N-propeptide of type 1 collagen (P1NP) and osteocalcin] were measured prospectively over one week in 22 eunatraemic patients with subarachnoid haemorrhage. Patients treated with glucocorticoids were excluded.

RESULTS

Eight patients developed acute hyponatraemia, median nadir plasma sodium concentration 131 mmol/L (IQR 128-132), and 14 remained eunatraemic, nadir plasma sodium concentration 136 mmol/L (IQR 133-137). Significant main effects of hyponatraemia were found for P1NP (p = .02) and P1NP:CTX-1 ratio (p = .02), both fell in patients with acute hyponatraemia, with significant interaction between hyponatraemia and time from baseline for P1NP (p = .02). Significant main effects of time from baseline (p < .001) but not hyponatraemia (p = .07) were found for osteocalcin. For CTX-1, significant main effects of time from baseline (p = .001) but not hyponatraemia (p = .65) were found. There was a positive correlation between change in P1NP:CTX-1 ratio and nadir plasma sodium concentration, r = +.43, p = .04. Median serum cortisol (measured on days 1, 3 and 7) was higher in the hyponatraemia group than in those who remained eunatraemic, 545 nmol/L (IQR 373-778) versus 444 nmol/L (IQR 379-542) p = .03.

CONCLUSION

These data suggest that acute mild hyponatraemia is associated with a reduction in bone formation activity.

Analytical considerations and plans to standardize or harmonize assays for the reference bone turnover markers PINP and β-CTX in blood

Procollagen type I N-propeptide (PINP) and the C-terminal telopeptide of type I collagen (β-CTX) in blood have been designated as reference bone turnover markers in osteoporosis by the International Osteoporosis Foundation (IOF) and International Federation of Clinical Chemistry and Laboratory Medicine (IFCC). The IFCC Committee on Bone Metabolism (C-BM) has examined current commercial assays and performed a multicentre study to examine the agreement between assays for PINP and β-CTX in serum and plasma. The results of these studies will inform our work towards the harmonization of PINP assays and the standardization of β-CTX assays in blood, with the development of common calibrators and reference measurement procedures in collaboration with the reagent manufacturing industry. Successful achievement of these goals will help develop universally acceptable practice guidelines for the management of osteoporosis with the inclusion of common reference intervals and treatment targets for PINP and β-CTX.

The effects of acute exercise on bone turnover markers in middle-aged and older adults: A systematic review

BACKGROUND

Bone turnover is the cellular machinery responsible for bone integrity and strength and, in the clinical setting, it is assessed using bone turnover markers (BTMs). Acute exercise can induce mechanical stress on bone which is needed for bone remodelling, but to date, there are conflicting results in regards to the effects of varying mechanical stimuli on BTMs.

OBJECTIVES

This systematic review examines the effects of acute aerobic, resistance and impact exercises on BTMs in middle and older-aged adults and examines whether the responses are determined by the exercise mode, intensity, age and sex.

METHODS

We searched PubMed, SCOPUS, Web of Science and EMBASE up to 22nd April 2020. Eligibility criteria included randomised controlled trials (RCTs) and single-arm studies that included middle-aged (50 to 65 years) and older adults (>65 years) and, a single-bout, acute-exercise (aerobic, resistance, impact) intervention with measurement of BTMs. PROSPERO registration number CRD42020145359.

RESULTS

Thirteen studies were included; 8 in middle-aged (n = 275, 212 women/63 men, mean age = 57.9 ± 1.5 years) and 5 in older adults (n = 93, 50 women/43 men, mean age = 68.2 ± 2.2 years). Eleven studies included aerobic exercise (AE, 7 middle-aged/4 older adults), and two included resistance exercise (RE, both middle-aged). AE significantly increased C-terminal telopeptide (CTX), alkaline phosphatase (ALP) and bone-ALP in middle-aged and older adults. AE also significantly increased total osteocalcin (tOC) in middle-aged men and Procollagen I Carboxyterminal Propeptide and Cross-Linked Carboxyterminal Telopeptide of Type I Collagen in older women. RE alone decreased ALP in older adults. In middle-aged adults, RE with impact had no effect on tOC or BALP, but significantly decreased CTX. Impact (jumping) exercise alone increased Procollagen Type 1 N Propeptide and tOC in middle-aged women.

CONCLUSION

Acute exercise is an effective tool to modify BTMs, however, the response appears to be exercise modality-, intensity-, age- and sex-specific. There is further need for higher quality and larger RCTs in this area.

FEATURES OF BONE METABOLISM AND THEIR INFLUENCE ON ARTERIAL WALL STIFFNESS IN POSTMENOPAUSAL WOMEN WITH CONTROLLED UNCOMPLICATED HYPERTENSION

The aim of this study was to investigate the features of bone metabolism and their influence on the arterial wall stiffness in postmenopausal women with a controlled uncomplicated arterial hypertension (AH). The study involved 44 women (main group) with the mean age of 69.04±0.72 years and a postmenopausal duration of 18.4±0.85 years, suffering from an AH grade 2, and 30 healthy patients (control group), their mean age being 69.3±1.21 years, postmenopausal duration 19.4±1.18 years (p>0.05). All patients underwent general clinical and laboratory examination with determination of lipid level in blood. Pulse wave analysis (SphygmoCor) parameters , Bone mineral density (BMD) were assessed. The levels of 25(OH) D, parathyroid hormone, propeptide procollagen of type 1 aminoterminal (P1NP), b-isomerized C-terminal telopeptides (b-CTx), ionized calcium and phosphorus in serum were assessed. The data obtained from the study of the parameters of applanation tonometry and the structural and functional state of bone tissue in patients with an uncomplicated hypertension at the age of 69±3.30 years manifest the likelihood of joint pathogenetic mechanisms of developing atherocalcinosis, increased vascular stiffness and impending osteoporosis.

Consensus Statement on the Use of Bone Turnover Markers for Short-Term Monitoring of Osteoporosis Treatment in the Asia-Pacific Region

Osteoporosis is a major health issue. By 2050, a greater than 2-fold increase in patients number with hip fractures will occur in Asia representing 50% of all hip fractures worldwide. For the Asia-Pacific (AP) region, more efforts on controlling osteoporosis and the subsequent fractures are crucial. Bone mineral density (BMD) by dual energy X-ray absorptiometry (DXA) is commonly used to diagnose osteoporosis and monitor osteoporosis treatment. However, the inconvenience, cost, limited availability of DXA and the delay in detection of BMD changes after treatment initiation support an important role for bone turnover markers (BTMs), as short-term tools to monitor therapy. With regards to low adherence rates of medical treatment of osteoporosis, the experts reached consensus on the use of BTMs for both raising awareness and short-term monitoring of osteoporosis treatment in the AP region. The experts endorse the use of BTMs, especially serum C-terminal telopeptide of type 1 collagen (CTX) and serum procollagen type 1 N propeptide (P1NP), as short-term monitoring tools to help clinicians assess the responses to osteoporosis therapies and appropriately adjust treatment regimens earlier than BMD. Either the absolute values or the degree of change from baseline in BTMs can be used to monitor the potential efficacy of osteoporosis therapies. The use of BTMs can be incorporated in osteoporosis care programs, such as fracture liaison service (FLS), to improve patient adherence and treatment outcomes. Encouraging sufficient reimbursement from health care systems may facilitate widespread use of BTMs in clinical practice in the AP region.

LEVELS OF OSTEOCALCIN AND PROCOLLAGEN I N-TERMINAL PROPEPTIDE (PINP) IN MEN SUFFERING FROM ANKYLOSING SPONDYLITIS

OBJECTIVE

The aim: To evaluate osteocalcin and PINP levels in men suffering from AS and to compare them with structural and functional state of bone tissue and clinical course of illness.

PATIENTS AND METHODS

Materials and methods: The study included 82 patients suffering from AS with an average age of 40,9±0,9 years. Osteocalcin level was determined in 82 patients, and PINP level was determined in 79 patients. Control group included 22 apparently healthy persons. Disease activity was assessed through CRP level, ASDAS and BASDAI scores, while functional ability was assessed through the BASFI score. Osteocalcin and PINP levels were determined by immunoenzymatic method for the purpose of evaluating the metabolic state of bone tissue.

RESULTS

Results: Average osteocalcin and PINP levels were not significantly different in patients suffering from AS and patients in the control group and did not show any significant correlation with ASDAS, BASDAI, BASFI and CRP scores. In patients with spinal ankylosis, average osteocalcin values (14,3 ng\ml) and PINP (747,2 pg\ml) were higher compared to patients with single syndesmophytes (11,0 ng\ml; 711,8 pg\ml) and patients without syndesmophytes (10,4 ng\ml; 537,7 pg\ml respectively).

CONCLUSION

Conclusions: Osteocalcin and PINP levels are not related to age, disease duration, BMI, glucocorticoids load and inflammatory process activity, however, they are closely related to the presence of bone growths.