Biomarkers Of Bone Resorption Research Articles

The Temporal Change in Ionised Calcium, Parathyroid Hormone and Bone Metabolism Following Ingestion of a Plant-Sourced Marine Mineral + Protein Isolate in Healthy Young Adults

Background: An increase in plant-sourced (PS) nutrient intake is promoted in support of a sustainable diet. PS dietary minerals and proteins have bioactive properties that can affect bone health and the risk of fracture. Methods: In a group randomised, cross-over design, this study evaluated the post-ingestion temporal pattern of change in arterialised ionised calcium (iCa), parathyroid hormone (PTH), C-terminal crosslinked telopeptide of type I collagen (CTX) and procollagen type 1 amino-terminal propeptide (P1NP) for 4 h following ingestion of a novel supplement (SUPP) containing a PS marine multi-mineral + PS protein isolate. A diurnally matched intake of mineral water was used as a control (CON). Results: Compared to baseline, the change in iCa concentration was 0.022 (95% CI, 0.006 to 0.038, p = 0.011) mmol/l greater in SUPP than CON, resulting in a −4.214 (95% CI, −8.244 to −0.183, p = 0.042) pg/mL mean reduction in PTH, a −0.64 (95% CI, −0.199 to −0.008, p = 0.029) ng/mL decrease in the biomarker of bone resorption, CTX, and no change in the biomarker of bone formation, P1NP. Conclusions: When used as a dietary supplement, or incorporated into a food matrix, the promotion of PS marine multi-mineral and PS protein isolates may contribute to a more sustainable diet and overall bone health.

Impact of Lactobacillus acidophilus and Its Combination with Isoflavone Products on Calcium Status, Calcium Transporters, and Bone Metabolism Biomarkers in a Post-Menopausal Osteoporotic Rat Model.

Osteoporosis in menopausal women requires alternatives to current medications, considering their adverse effects. In this context, probiotics and isoflavone products are promising dietary interventions. The objective of our study was to examine the impacts of Lactobacillus acidophilus and its combination with daidzein and tempeh on calcium status, calcium transporters, and bone metabolism biomarkers in a post-menopausal osteoporotic rat model. A total of 48 female Wistar rats were exposed to a two-stage experiment involving calcium deficit induction and subsequent dietary interventions across six groups. Calcium levels, the gene expression of TRPV5 and TRPV6 calcium transporters, bone histopathology, serum bone metabolism markers, and blood biochemistry were evaluated. The results revealed that, while decreasing serum calcium levels, the groups that received the probiotic L. acidophilus and isoflavone combination exhibited increased bone metabolism biomarkers and decreased calcium transporter expressions, akin to the effects of bisphosphonate. Additionally, significant improvements in bone histopathology were observed in these groups. However, the group receiving probiotic L. acidophilus alone did not exhibit significant changes in bone resorption biomarkers, calcium transporter expression, or various blood parameters. Meanwhile, the combination of probiotic L. acidophilus with tempeh positively influenced hematological parameters and reduced cholesterol and triglyceride levels, but it led to elevated blood glucose levels. Correlation analyses highlighted associations between serum calcium levels, calcium transporter expression, and bone metabolism biomarkers. In conclusion, our findings suggest that the daily consumption of probiotic L. acidophilus in combination with isoflavone products may improve bone health in ovariectomized rats, warranting further research to elucidate potential interactions with other nutrients.

#1235 Comparative effect on bone remodeling and inflammation biomarkers of citrate dialysate and bicarbonate dialysate in HDF-OL patients

Abstract Background and Aims Hemodialysis (HD) treatment increases the inflammatory state of chronic kidney disease (CKD), which is associated with dysregulation of mineral bone metabolism. Reduced inflammation and increased bone formation have been described in Hemodiafiltration (HDF) compared with conventional HD. On the other hand, HD and OL-HDF using citrate-enriched dialysate are known to be safe and anti-inflammatory. However, the effects of post-dilution OL-HDF with citrate dialysate compared to bicarbonate dialysate on biomarkers of bone formation and resorption have not been studied. We aimed to compare the effect of bone remodeling markers and inflammation of different dialysates (citrate vs bicarbonate) in post dilution OL- HDF treatment. Method A total of 33 patients on conventional HD with bicarbonate citrate were included. At month 1, 18 patients, who did not require individualized adjustment of the dialysate composition such as potassium, were changed to HD with citrate dialysate and 15 patients remained with bicarbonate dialysate. By the second month, however, all patients were on OL-HDF with no change in buffer dialysate. Pre-dialysis blood samples were taken in both treatment groups at baseline (prior to the initiation of citrate dialysate in 18 patients), and at the first, second and fifth months after the introduction of citrate. Measurements of mineral homeostasis (calcium, phosphate, magnesium, parathyroid hormone, intact parathyroid hormone), inflammation (interleukin-6, β2-microglobulin, C-reactive protein) and bone remodeling markers (carboxy-terminal crosslinked telopeptide of type 1 collagen (CTX), as a biomarker of bone resorption and procollagen type 1 N-terminal pro-peptide (P1NP), as a biomarker of bone formation) were performed. All samples were collected before a mid-week dialysis session. Mineral homeostasis measurements were also performed before and after HD at the first and second month of the switch to citrate dialysate. Normally distributed data were presented as mean (standard deviation, SD) and median (interquartile range). Intra-subjects comparisons were analyzed using paired sample t-test or Wilcoxon signed-rank test. Comparisons between groups were analyzed using Mann-Whitney U test. Statistical analyses were performed using the SPSS (version 15.0, Chicago, IL, USA). p-value < 0.05. Results Overall, 75.7% (n = 25) of the subjects were male, the median age was 69 years (SD: 12) and 39.3% suffered diabetes (n = 13). Patients on citrate and bicarbonate dialysates were comparable for age, sex, comorbidities, months on dialysis and anemia control. Baseline mineral, bone remodeling and inflammation markers before HD, were also comparable in both groups. Only patients on bicarbonate dialysate had higher β2-microglobulin levels at baseline. Changes in serum levels of mineral, bone remodeling and inflammatory biomarkers at 5 months compared to baseline for both groups are shown in Table 1. After 5 months of follow-up, a 22% trend-reduction (p = 0.08) in P1NP as bone formation biomarker was observed in patients on citrate dialysate compared to those on bicarbonate dialysate. In addition, the fold change observed in CTX as parameter of bone resorption was attenuated in the citrate dialysate group (11% vs 116% in the bicarbonate dialysate group, p < 0.001). β2-microglobulin levels decreased significantly in both groups at 5 months but It is explained by the known effect of OL-HDF treatment on the inflammatory state of dialysis patients. Conclusion In patients on OL-HDF treatment the use of the citrate as dialysate may provide a benefit in bone remodeling by reducing bone resorption and trend to balance the bone formation/resorption. However, our results are in line with previous studies, where caution should be adopted in patients with very high parathyroid hormone levels, as this may be enhanced by reduced mineral turnover.

Exploring the anti-osteoporosis potential of Petroselinum crispum (Mill.) Fuss extract employing experimentally ovariectomized rat model and network pharmacology approach

One of the most prevalent secondary osteoporosis is ovariectomy-induced osteoporosis. Parsley (Petroselinum crispum) has potent estrogenic and antioxidant properties and was used traditionally in the treatment of amenorrhea and dysmenorrhea. The present study aimed to characterize parsley leaf extract (PLE) employing RP-HPLC-MS-MS/MS-based method and possible protective effect in ovariectomized (OVX)-induced osteoporosis in rats was assessed. Rats were randomly assigned into SHAM group, OVX group, PLE + OVX group (150 mg/kg/day, p.o), and estradiol benzoate (E2) + OVX group (30 μg/kg/day, s.c). After eight weeks following ovariectomy, biomarkers of bone strength, bone resorption, oxidative stress and histopathology were carried out. A network pharmacology approach investigated the key targets and potential mechanisms by of PLE metabolites against osteoporosis using databases: PubChem, BindingDB server, DisGeNET, ShinyGO, and KEGG Pathway. Moreover, FunRich 3.1.3, Cytoscape 3.10.0, and MOE 2019.0102 softwares were used for network pharmacology analysis and molecular docking studies.Flavones and hydroxycinnamic acid derivatives were predominant among 38 metabolites in PLE. It significantly restored bone strength and bone resorption biomarkers, osteocalcin (OST), oxidative stress biomarkers and histopathological alterations. The employed network pharmacology approach revealed that 14 primary target genes were associated with decreasing the severity of osteoporosis. Molecular docking revealed that cGMP-PKG signaling pathway has the highest fold enrichment and its downstream PDE5A. Luteolin, diosmetin, and isorhamnetin derivatives affected mostly osteoporosis targets. PLE exhibited protective action against ovariectomy-induced osteoporosis in rats and may be a promising therapy for premenopausal bone loss. cGMP-PKG signaling pathway could be a promising target for PLE in treating osteoporosis.

Analysis of inflammation and bone remodeling of atmospheric plasma therapy in experimental periodontitis.

The biological effects of atmospheric plasma (cold plasma) show its applicability for controlling the etiological factors that involve tissue repair. Thus, the study evaluated the effect of atmospheric plasma therapy in the control of tissue inflammation and bone remodeling in experimental periodontitis. Fifty-six rats were subjected to ligation in the cervical region of the first maxillary molars (8 weeks). The animals were divided into two groups (n = 28): periodontitis without treatment group (P group), and periodontitis with atmospheric plasma treatment group (P + AP group). Tissue samples were collected at 2 and 4 weeks after treatment to analyze the inflammation and bone remodeling by biochemical, histomorphometric, and immunohistochemical analyses. Inflammatory infiltration in the gingival and periodontal ligament was lower in the P + AP group than in the P group (p < .05). The MPO and NAG levels were higher in the P + AP group compared to P group (p < .05). At 4 weeks, the TNF-α level was lower and the IL-10 level was higher in the P + AP group compared to P group (p < .05). In the P + AP group, the IL-1β level increased in the second week and decreased in the fourth week (p < .05), the number of blood vessels was high in the gingival and periodontal ligament in the second and fourth week (p < .05); and the number of fibroblasts in the gingival tissue was low in the fourth week, and higher in the periodontal tissue in both period (p < .05). Regarding bone remodeling, the RANK and RANKL levels decreased in the P + AP group (p < .05). The OPG level did not differ between the P and P + AP groups (p > .05), but decreased from the second to the fourth experimental week in P + AP group (p < .05). The treatment of experimental periodontitis with atmospheric plasma for 4 weeks modulated the inflammatory response to favor the repair process and decreased the bone resorption biomarkers, indicating a better control of bone remodeling in periodontal disease.

Amorphous Calcium Carbonate from Plants Can Promote Bone Growth in Growing Rats.

This study aimed to investigate the effect of amorphous calcium carbonate (ACC) supplementation on bone growth in growing rats. We used 3-week-old male Wistar rats to simulate childhood and adolescent growth stages. Rats were divided into four groups as follows: a control group (C), a low-dose group (L, 20.65 mg/kg body weight (BW) ACC), a medium-dose group (M, 206.5 mg/kg BW ACC), and a high-dose group (H, 413 mg/kg BW ACC) administered by gavage. Body length (BL) and BW were measured weekly. The bone mineral density (BMD) of two lumbar vertebrae (L3 and L4) and the left femur were analyzed by micro-computed tomography (μCT) at 0, 4, 8, and 12 weeks. At the end of 12 weeks, the rats were sacrificed. After that, blood samples were collected from the abdominal aorta. Femurs and tibias were collected and weighed, and their lengths were measured. Then, bone samples were used to perform histopathological and histomorphometric analyses. It showed that ACC supplementation in growing rats increased the trabecular bone thickness and serum bone formation biomarkers. Furthermore, high-dose ACC decreased serum bone resorption biomarkers and increased BMD. ACC supplementation can enhance osteoblast metabolism and inhibit osteoclast metabolism, resulting in a higher bone formation rate compared to bone resorption. This led to increased trabecular bone thickness, a higher BMD, and supported bone growth.

Bone resorption biomarkers and proinflammatory cytokines in Gaucher disease

Bone resorption biomarkers and proinflammatory cytokines in Gaucher disease

Comparing the Effect of Bone-loading Exercises and Pulsed Electromagnetic Fields on Bone Turnover Markers in Women with Osteoporosis: A Randomized Clinical Trial Study Protocol.

Given the bone sensitivity to mechanical stimulus, bone-loading exercises and applying the Pulsed Electromagnetic Fields (PEMF(s)) are recommended for promoting bone strength. In this context, these two interventions 's effect on bone turnover markers (BTMs) in osteoporosis patients is yet to be clarified; consequently, an attempt is made in this study to compare the effect of these two interventions on bone turnover markers in women with Postmenopausal Osteoporosis (PMOP). This study is design as a randomized, single-center, three-arms, controlled trial. A total of 51 women with PMOP will be randomly assigned to three groups of 17, using opaque, sealed envelopes containing labels for A, B, and C groups. Group A) will receive bone-loading exercises, B) will follow the PEMF(s) and C) will be exposed to the combination of A and B. These three groups will require intervention for 24 sessions (2 sessions/week) next to their routine medical treatment (Alendronate+ Calcium+ Vitamin D). The primary outcome of this study is the serum biomarker of bone formation (bone-specific alkaline phosphatase, BSALP) and resorption (N-terminal telopeptide, NTX). The secondary outcomes consist of thoracic kyphosis angle, fear of falling, and quality of life. The outcomes are measured three times: at baseline, after 24 sessions of intervention, and at 12 weeks follow-up. A primary outcome will be measured and reported by a laboratory expert who is blinded to the participant grouping. The trial has the code of ethics for research (IR.TUMS.FNM.REC.1401.126) and the code of Iranian Registry of Clinical Trials (IRCT) (IRCT20221202056687N1). Study results are expected to be available by mid-2024. This trial will provide new practical knowledge on the bone-loading exercises and PEMFS(s)'s effect on PMOP women. This knowledge is of the essence for physiotherapists, clinicians, other healthcare professionals, and policymakers in the healthcare system.

Prenatal but not continued postpartum vitamin D supplementation reduces maternal bone resorption as measured by C-terminal telopeptide of type 1 collagen without effects on other biomarkers of bone metabolism

Vitamin D is a key regulator of bone mineral homeostasis and may modulate maternal bone health during pregnancy and postpartum. Using previously-collected data from the Maternal Vitamin D for Infant Growth (MDIG) trial in Dhaka, Bangladesh, we aimed to investigate the effects of prenatal and postpartum vitamin D3 supplementation on circulating biomarkers of bone formation and resorption at delivery and 6 months postpartum. MDIG trial participants were randomized to receive a prenatal;postpartum regimen of placebo or vitamin D3 (IU/week) as either 0;0 (Group A), 4200;0 (B), 16,800;0 (C), 28,000;0 (D) or 28,000;28,000 (E) from 17 to 24 weeks' gestation to 6 months postpartum. As this sub-study was not pre-planned, the study sample included MDIG participants who had data for at least 1 biomarker of interest at delivery or 6 months postpartum, with a corresponding baseline measurement (n = 690; 53 % of 1300 enrolled trial participants). Biomarkers related to bone turnover were measured in maternal venous blood samples collected at enrolment, delivery, and 6 months postpartum: osteoprotegerin (OPG), osteocalcin (OC), receptor activator nuclear factor kappa-B ligand (RANKL), fibroblast growth factor 23 (FGF23), procollagen type 1 N-terminal propeptide, (P1NP) and carboxy terminal telopeptide of type 1 collagen (CTx). Supplementation effects were expressed as percent differences between each vitamin D group and placebo with 95 % confidence intervals (95 % CI). Of 690 participants, 64 % had 25-hydroxyvitamin D concentrations (25OHD) <30 nmol/L and 94 % had 25OHD < 50 nmol/L at trial enrolment. At delivery, mean CTx concentrations were 27 % lower in group E versus placebo (95 % CI: −38, −13; P < 0.001), adjusting for enrolment concentrations. However, at 6 months postpartum, CTx concentrations were not statistically different in group E versus placebo (14 %; 95 % CI: −5.3, 37; P = 0.168), adjusting for delivery CTx concentrations. Effects on other biomarkers at delivery or postpartum were not statistically significant. In conclusion, prenatal high-dose vitamin D supplementation reduced bone resorption during pregnancy, albeit by only one biomarker, and without evidence of a sustained effect in the postpartum period. However, further evidence is needed to substantiate potential maternal bone health benefits of vitamin D in the postpartum period.

Time of day of exercise does not affect the beneficial effect of exercise on bone structure in older female rats.

Background: Circadian clock genes are expressed in bone and biomarkers of bone resorption and formation exhibit diurnal patterns in animals and humans. Disruption of the diurnal rhythms may affect the balance of bone turnover and compromise the beneficial effects of exercise on bone. Objective: This study investigated whether the time of day of exercise alters bone metabolism in a rodent model. We hypothesized that exercise during the active phase results in greater bone mass than exercise during the rest phase in older female rats. Methods: Fifty-five, female 12-month-old Sprague Dawley rats were randomly assigned to four treatment groups (n = 13-14/group). Rats were subjected to no exercise or 2h of involuntary exercise at 9m/min and 5days/wk for 15weeks using motor-driven running wheels at Zeitgeber time (ZT) 4-6 (rest phase), 12-14 (early active phase), or 22-24 (late active phase). ZT 0 is defined as light on, the start of the rest phase. A red lamp was used at minimal intensity during the active, dark phase exercise period, i.e., ZT 12-14 and 22-24. Bone structure, body composition, and bone-related cytokines in serum and gene expression in bone were measured. Data were analyzed using one-way ANOVA followed by Tukey-Kramer post hoc contrasts. Results: Exercise at different ZT did not affect body weight, fat mass, lean mass, the serum bone biomarkers, bone structural or mechanical parameters, or expression of circadian genes. Exercise pooled exercise data from different ZT were compared to the No-Exercise data (a priori contrast) increased serum IGF-1 and irisin concentrations, compared to No-Exercise. Exercise increased tibial bone volume/total volume (p = 0.01), connectivity density (p = 0.04), and decreased structural model index (p = 0.02). Exercise did not affect expression of circadian genes. Conclusion: These data indicate that exercise is beneficial to bone structure and that the time of day of exercise does not alter the beneficial effect of exercise on bone in older female rats.

Prospective Assessment of Bone Metabolism Biomarkers and Survival in Metastatic Castration-resistant Prostate Cancer Patients Treated with Radium-223: The PRORADIUM Study

BackgroundRadium-223 is an active therapy option for bone metastatic castration-resistant prostate cancer (mCRPC). The lack of adequate biomarkers for patient selection and response assessment are major drawbacks for its use. ObjectiveTo assess the prognostic value of bone metabolism biomarkers (BMBs) in ra-223–treated mCRPC patients. Design, setting, and participantsA prospective cohort study of mCRPC patients treated with Ra-223 (PRORADIUM study: NCT02925702) was conducted. Outcome measurements and statistical analysisThe main objective of the study was to evaluate the association between high (≥median) baseline values in at least three bone formation (bone alkaline phosphatase [BAP] and C-terminal type-I collagen propeptide) and bone resorption (N-terminal telopeptide and pyridinoline) biomarkers, and survival. The independent prognostic value of each BMB was also assessed. The association with time to radiographic, clinical, and prostate-specific antigen (PSA) progression; time to skeletal-related events; and PSA response were secondary objectives. Multivariable (MV) Cox-regression models were evaluated. Results and limitationsA total of 169 patients were included. Of the patients, 70.4% received Ra-223 in second/third line; 144 (85.2%) were Eastern Cooperative Oncology Group 0–1, 126 (74.6%) were in pain, and 80 (47.5%) had more than ten bone metastases. Sixty-seven (39.6%) patients had elevation in at least three BMBs. The median overall survival was 12.1 mo (95% confidence interval [CI]: 10–14.7). No association was observed with other treatment-related secondary outcome parameters. Patients with high values in three or more BMBs had significantly worse survival (9.9 vs 15.2 mo; hazard ratio [HR]: 1.8 [95% CI: 1.3–2.5]; p < 0.001) in the univariate analysis, but not independent in the MV analysis (HR: 1.33; 95% CI: 0.89–2; p = 0.181). High baseline BAP was the only biomarker associated with survival in the MV model (HR: 1.89; 95% CI: 1.28–2.79; p = 0.001). Addition of BAP to the MV clinical model increased the area under the receiver operating characteristic curve 2-yr value from 0.667 to 0.755 (p = 0.003). ConclusionsBiomarkers of bone formation, especially BAP, have prognostic value in mCRPC patients treated with radium-223. Its predictive value remains to be assessed, ideally in prospective, adequately powered, randomised clinical trials. Patient summaryIn this study, we evaluate the role of bone metabolism biomarkers to help improve the use of radium-223 as therapy for advanced prostate cancer. We found that bone alkaline phosphatase may be a suitable tool.

Yacon (Smallanthus sonchifolius) and kefir improved intestinal and bone health but without symbiotic benefits in rats

Kefir is a natural source of probiotics, and yacon (Smallanthus sonchifolius) is a tuberous root rich in fructooligosaccharides, with prebiotic properties. We hypothesized that kefir and yacon can improve bone and intestinal health and that their synbiotic effects will enhance these benefits. The properties of yacon and kefir and their association were evaluated in the intestinal and bone health in rats. Forty Wistar male rats were divided into 4 groups (n = 10): control (C), kefir (K), yacon (Y), and yacon + kefir (YK) and received an AIN-93 M diet containing 50% of the daily recommendation of calcium for 42 days. Group K received 1 mL/day of kefir containing 10⁸ CFU/mL; group Y received yacon flour (5% fructooligosaccharides); and the YK group received the same treatment as the Y and K groups. Urine and feces were collected to determine the calcium balance. Serum biomarkers of bone formation and resorption, osteocalcin, N telopeptides of collagen type I and C-telopeptide of collagen type I, intraluminal pH, intestinal permeability, and secretory immunoglobulin A were evaluated. Yacon reduced intraluminal pH alone or in association with kefir (groups Y and YK). Yacon also improved intestinal permeability (lowered lactulose and mannitol excretion) and increased calcium balance and osteocalcin, a biomarker of bone formation. In turn, K improved immunity by increasing secretory immunoglobulin A secretion and reducing bone resorption biomarkers (C-telopeptide of collagen type I and N telopeptides of collagen type I). Thus, yacon and kefir had beneficial effects on intestinal and bone health; however, the association between them did not demonstrate a synbiotic effect.

Innovative workflow for the identification of cathepsin K cleavage sites in type I collagen

Since the late 1990s, cathepsin K cleavage sites in type I collagen have been extensively studied due to its ability to release bone resorption biomarkers such as CTX and NTX. However, gel-based methods and N-sequencing used in these studies lack sensitivity, especially for small to medium peptides. In this work, we propose a degradomics mass spectrometry-based workflow that combines protein digestion, Nano-LC-UDMSE, and several software tools to identify cathepsin K cleavage sites. This workflow not only identified previously known cleavage sites, but also discovered new ones. Multiple cleavage hotspots were found and described in type I α1 and type I α2 collagen, many of which coincided with pyridinoline crosslinks, known to stabilize the triple helix. Our results allowed us to establish a chronology of digestion and conclude that cathepsin K preferentially cleaves the extremities of type I collagen before the helical part. We also found that cathepsin K preferentially cleaves amino acid residues with long and hydrophobic lateral chains at the beginning of digestion, whereas no preferred amino acid residues were identified later in the digestion. In conclusion, our workflow successfully identified new cleavage sites and can be easily applied to other proteins or proteases.

Moderate consumption of freeze-dried blueberry powder increased net bone calcium retention compared with no treatment in healthy postmenopausal women: a randomized crossover trial

BackgroundPreclinical studies suggest that blueberry consumption is associated with improved bone health. ObjectivesWe conducted a blueberry dose-response study in ovariectomized (OVX)-rats that informed a study in postmenopausal women using the urinary appearance of calcium (Ca) tracers from prelabeled bone to reflect changes in bone balance. We hypothesized that blueberry consumption would reduce bone loss in a dose-dependent manner compared with no treatment. MethodsOVX rats were fed 4 doses of blueberry powder (2.5%, 5%, 10%, and 15%) in randomized order to determine bone 45Ca retention. Fourteen healthy, nonosteoporotic women ≥4 y past menopause were dosed with 50 nCi of 41Ca, a long-lived radioisotope, and equilibrated for 5 mo to allow 41Ca deposition in bone. Following a 6-wk baseline period, participants were assigned to a random sequence of 3 6-wk interventions, a low (17.5 g/d), medium (35 g/d), or high (70 g/d) dose of freeze-dried blueberry powder equivalent to 0.75, 1.5, or 3 cups of fresh blueberries incorporated into food and beverage products. Urinary 41Ca:Ca ratio was measured by accelerator mass spectrometry. Serum bone resorption biomarkers and urinary polyphenols were measured at the end of each control and intervention period. Data were analyzed using a linear mixed model and repeated measures analysis of variance. ResultsIn both OVX rats and postmenopausal women, blueberry interventions benefited net bone calcium balance at lower but not at higher doses. In women, net bone calcium retention increased by 6% with the low (95% CI: 2.50, 8.60; P < 0.01) and 4% with the medium (95% CI: 0.96, 7.90; P < 0.05) dose compared with no treatment. Urinary excretion of hippuric acid increased dose-dependently with blueberry consumption. No significant relationships were found between bone resorption biomarkers, 25-hydroxyvitamin D, and interventions. ConclusionsModerate consumption (<1 cup/d) of blueberries may be an effective strategy to attenuate bone loss in healthy postmenopausal women.This trial was registered at clinicaltrials.gov as NCT02630797.

MMPs/TIMPs ratio: A Biomarker of Bone Resorption in Geriatric Osteoporosis?

Matrix metalloproteinases (MMPs) play an important role in bone resorption and are regulated by tissue inhibitors of metalloproteinases (TIMPs). We investigated the use of MMP2/TIMP2 and MMP9/TIMP1 ratios as biomarkers of bone resorption in geriatric osteoporosis and evaluated the relationship between osteoporosis and geriatric syndromes. This analytical cross-sectional study involved 87 patients (41 with osteoporosis) treated at the geriatric outpatient clinic of a university hospital. The demographic characteristics, comprehensive geriatric assessment scores, laboratory findings, and bone mineral density of the patients were recorded. Serum MMP9, TIMP1, MMP2, and TIMP2 levels were analyzed by enzyme-linked immunosorbent assay (ELISA). We enrolled 41 and 46 patients with and without osteoporosis, respectively. The groups showed no significant differences in MMP2/TIMP2 and MMP9/TIMP1 ratios (p=0.569 and p=0125, respectively). While the basic activities of daily life (BADL) scores in the osteoporosis group were higher than those in the group without osteoporosis, the instrumental activities of daily life (IADL) scores were significantly lower (p=0.001 and p=0.007, respectively). No significant differences were observed in Mini-Nutritional Assessment (MNA), Mini-Mental State Examination (MMSE), and Geriatric Depression Scale (GDS) scores (p=0.598, p=0.898, and p=0.287, respectively). This is the first study to examine the relationship between osteoporosis and several geriatric syndromes, as well as the relationship between osteoporosis and serum MMP, TIMP values, and MMP/TIMP ratios in geriatric patients. Our results showed that osteoporosis causes dependency in both BADLs and IADLs, and that the MMP2/TIMP2 and MMP9/TIMP1 ratios provided no additional benefit in demonstrating bone resorption in geriatric osteoporosis.

Bone resorption and incretin hormones following glucose ingestion in healthy emerging adults

BackgroundStudies in adults indicate that macronutrient ingestion yields an acute anti-resorptive effect on bone, reflected by decreases in C-terminal telopeptide (CTX), a biomarker of bone resorption, and that gut-derived incretin hormones, glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1), facilitate this response. There remain knowledge gaps relating to other biomarkers of bone turnover, and whether gut-bone cross-talk is operative during the years surrounding peak bone strength attainment. This study first, describes changes in bone resorption during oral glucose tolerance testing (OGTT), and second, tests relationships between changes in incretins and bone biomarkers during OGTT and bone micro-structure. MethodsWe conducted a cross-sectional study in 10 healthy emerging adults ages 18–25 years. During a multi-sample 2-hour 75 g OGTT, glucose, insulin, GIP, GLP-1, CTX, bone-specific alkaline phosphatase (BSAP), osteocalcin, osteoprotegerin (OPG), receptor activator of nuclear factor kappa-β ligand (RANKL), sclerostin, and parathyroid hormone (PTH) were assayed at mins 0, 30, 60, and 120. Incremental areas under the curve (iAUC) were computed from mins 0–30 and mins 0–120. Tibia bone micro-structure was assessed using second generation high resolution peripheral quantitative computed tomography. ResultsDuring OGTT, glucose, insulin, GIP, and GLP-1 increased significantly. CTX at min 30, 60, and 120 was significantly lower than min 0, with a maximum decrease of about 53 % by min 120. Glucose-iAUC0-30 inversely correlated with CTX-iAUC0-120 (rho = -0.91, P < 0.001), and GLP-1-iAUC0-30 positively correlated with BSAP-iAUC0-120 (rho = 0.83, P = 0.005), RANKL-iAUC0-120 (rho = 0.86, P = 0.007), and cortical volumetric bone mineral density (rho = 0.93, P < 0.001). ConclusionsGlucose ingestion yields an anti-resorptive effect on bone metabolism during the years surrounding peak bone strength. Cross-talk between the gut and bone during this pivotal life stage requires further attention.

The effect of statins on bone turnover biomarkers: a systematic review and meta-analysis of randomized controlled trials.

Few studies have considered the effect of statins on bone turnover biomarker levels and the results of these studies are inconsistent. Here we performed a meta-analysis of the effect of statins on bone turnover biomarker levels. We used keywords, free words, and related words that included the terms "hydroxymethylglutaryl-CoA reductase inhibitors," "statin," and "bone turnover biomarkers" to search PubMed, Cochrane Library, and Embase. The Cochrane Risk Bias Evaluation Tool was used to evaluate the risk of bias, and Review Manager 5.3 and Stata 13.0 were used for statistical analyses. Six randomized controlled trials involving a total of 382 subjects were included in the meta-analysis. The results showed that statins increased the osteocalcin (OC) [mean difference (MD) = 0.73 ng/mL, 95% CI: 0.12, 1.35, I2 = 23% and p = 0.26], and decreased cross-linked N-telopeptide (NTX) (MD = -1.14 nM BCE, 95% CI: -2.21, -0.07, I2 = 0%, p = 0.53) and C-terminal peptide of type I collagen (CTX) (MD = -0.03 ng/mL, 95% CI: -0.05, -0.01, I2 = 0% and p = 0.56). There was no effect on bone-specific alkaline phosphatase (MD = -1.37 U/L, 95% CI: -3.09, 0.34, I2 = 0% and p = 0.94) and intact parathyroid hormone (MD = -1.73 pg/mL, 95% CI: -4.35, 0.89, I2 = 0% and p = 0.77). Statins increase bone formation biomarker OC and decrease bone resorption biomarker NTX and CTX levels.

Effects of 25-hydroxycholecalciferol (25-OH-D3) and 1-hydroxycholecalciferol (1-OH-D3) on serum bone biomarkers and calcium and phosphorus balance and concentrations of energy in diets without or with microbial phytase fed to sows in late gestation.

The objective was to test the hypothesis that supplementation of diets for gestating sows with 25-hydroxycholecalciferol (25-OH-D3) or 1-hydroxycholecalciferol (1-OH-D3) affects serum biomarkers for bone and increases Ca and P balance and the apparent total tract digestibility (ATTD) of gross energy (GE), and the concentrations of digestible energy (DE) and metabolizable energy (ME) in diets without or with microbial phytase. Sixty multiparous sows were allotted to 1 of 6 diets. Diets were formulated using a 3 × 2 factorial with 3 inclusions of supplemental vitamin D metabolite (no metabolite, 25-OH-D3, or 1-OH-D3) and 2 inclusion levels of microbial phytase (0 or 1,000 units). Sows were housed individually in metabolism crates and feces and urine were collected quantitatively. Results indicated that there was no difference in the ATTD of dry matter (DM) and GE and concentration of DE among the 3 diets containing microbial phytase, but the ATTD of DM and GE and concentration of DE was greater (P < 0.05) in diets containing 1-OH-D3 compared with the diet without a vitamin D metabolite if phytase was not used (interaction; P < 0.05). In diets without microbial phytase, ME was greater in diets containing either one of the 2 vitamin D metabolites than in the diet without a vitamin D metabolite, but among diets with microbial phytase, the ME of the 1-OH-D3 diet was less than of the 25-OH-D3 diet (interaction; P < 0.05). No effect of microbial phytase on concentrations of DE and ME was observed. There was no interaction between supplementation of microbial phytase and vitamin D metabolites for Ca and P balances, and regardless of metabolite supplementation, use of microbial phytase increased (P < 0.05) the ATTD and retention of Ca and P. Regardless of dietary phytase, the ATTD and retention of Ca and P increased (P < 0.05) for sows fed a diet containing one of the vitamin D metabolites compared with sows fed the diet without a vitamin D metabolite. Serum biomarkers for bone resorption or bone tissue synthesis were not affected by experimental diets. In conclusion, the ATTD of DM and GE, concentrations of DE and ME, and Ca and P balance in phytase-free diets fed to sows in late gestation were increased by supplementation with 1-OH-D3 or 25-OH-D3, but no differences between the 2 vitamin D metabolites were observed. Supplementation of diets with microbial phytase increased Ca and P balance, but did not affect DE and ME of diets.

Bone metabolism and incretin hormones following glucose ingestion in young adults with pancreatic insufficient cystic fibrosis

BackgroundGut-derived incretin hormones, including glucose-dependent insulinotropic peptide (GIP) and glucagon-like peptide 1 (GLP-1), regulate post-prandial glucose metabolism by promoting insulin production. GIP, GLP-1, and insulin contribute to the acute bone anti-resorptive effect of macronutrient ingestion by modifying bone turnover. Cystic fibrosis (CF) is associated with exocrine pancreatic insufficiency (PI), which perturbs the incretin response. Cross-talk between the gut and bone (“gut-bone axis”) has not yet been studied in PI-CF. The objectives of this study were to assess changes in biomarkers of bone metabolism during oral glucose tolerance testing (OGTT) and to test associations between incretins and biomarkers of bone metabolism in individuals with PI-CF. MethodsWe performed a secondary analysis of previously acquired blood specimens from multi-sample OGTT from individuals with PI-CF ages 14–30 years (n = 23). Changes in insulin, incretins, and biomarkers of bone resorption (C-terminal telopeptide of type 1 collagen [CTX]) and formation (procollagen type I N-terminal propeptide [P1NP]) during OGTT were computed. ResultsCTX decreased by 32% by min 120 of OGTT (P < 0.001), but P1NP was unchanged. Increases in GIP from 0 to 30 mins (rho = -0.48, P = 0.03) and decreases in GIP from 30 to 120 mins (rho = 0.62, P = 0.002) correlated with decreases in CTX from mins 0–120. Changes in GLP-1 and insulin were not correlated with changes in CTX, and changes in incretins and insulin were not correlated with changes in P1NP. ConclusionsIntact GIP response was correlated with the bone anti-resorptive effect of glucose ingestion, represented by a decrease in CTX. Since incretin hormones might contribute to development of diabetes and bone disease in CF, the “gut-bone axis” warrants further attention in CF during the years surrounding peak bone mass attainment.

Effect of 24-Week, Late-Evening Ingestion of a Calcium-Fortified, Milk-Based Protein Matrix on Biomarkers of Bone Metabolism and Site-Specific Bone Mineral Density in Postmenopausal Women with Osteopenia.

Dietary calcium intake is a modifiable, lifestyle factor that can affect bone health and the risk of fracture. The diurnal rhythm of bone remodelling suggests nocturnal dietary intervention to be most effective. This study investigated the effect of daily, bed-time ingestion of a calcium-fortified, milk-derived protein matrix (MBPM) or control (CON), for 24 weeks, on serum biomarkers of bone resorption (C-terminal telopeptide of type I collagen, CTX) and formation (serum pro-collagen type 1 N-terminal propeptide, P1NP), and site-specific aerial bone mineral density (BMD), trabecular bone score (TBS), in postmenopausal women with osteopenia. The MBPM supplement increased mean daily energy, protein, and calcium intake, by 11, 30, and 107%, respectively. 24-week supplementation with MBPM decreased CTX by 23%, from 0.547 (0.107) to 0.416 (0.087) ng/mL (p < 0.001) and P1NP by 17%, from 60.6 (9.1) to 49.7 (7.2) μg/L (p < 0.001). Compared to CON, MBPM induced a significantly greater reduction in serum CTX (mean (CI95%); −9 (8.6) vs. −23 (8.5)%, p = 0.025 but not P1NP −19 (8.8) vs. −17 (5.2)%, p = 0.802). No significant change in TBS, AP spine or dual femur aerial BMD was observed for CON or MBPM. This study demonstrates the potential benefit of bed-time ingestion of a calcium-fortified, milk-based protein matrix on homeostatic bone remodelling but no resultant treatment effect on site-specific BMD in postmenopausal women with osteopenia.