Osteoporosis: a lifecourse approach

Polyaptamer-Driven Crystallization of Alendronate for Synergistic Osteoporosis Treatment through Osteoclastic Inhibition and Osteogenic Promotion

Osteoclastic inhibition using antiresorptive bisphosphonates and osteogenic promotion using antisclerostin agents represent two distinct osteoporosis treatments in clinical practice, each individual treatment suffers from unsatisfactory therapeutic efficacy due to its indirect intervention in osteoclasis and promotion of osteogenesis simultaneously. Although this issue is anticipated to be resolved by drug synergism, a tempting carrier-free dual-medication nanoassembly remains elusive. Herein, we prepare such a nanoassembly made of antiresorptive alendronate (ALN) crystal and antisclerostin polyaptamer (Apt) via a nucleic acid-driven crystallization method. This nanoparticle can protect Apt from rapid nuclease degradation, avoid the high cytotoxicity of free ALN, and effectively concentrate in the cancellous bone by virtue of the bone-binding ability of DNA and ALN. More importantly, the acid microenvironment of cancellous bone triggers the disassociation of nanoparticles for sustained drug release, from which ALN inhibits the osteoclast-mediated bone resorption while Apt promotes osteogenic differentiation. Our work represents a pioneering demonstration of nucleic acid-driven crystallization of a bisphosphonate into a tempting carrier-free dual-medication nanoassembly. This inaugural advancement augments the antiosteoporosis efficacy through direct inhibition of osteoclasis and promotion of osteogenesis simultaneously and establishes a paradigm for profound understanding of the underlying synergistic antiosteoporosis mechanism of antiresorptive and antisclerostin components. It is envisioned that this study provides a highly generalizable strategy applicable to the tailoring of a diverse array of DNA-inorganic nanocomposites for targeted regulation of intricate pathological niches.

Osteoporotic Fractures: Diagnosis, Evaluation, and Significance From the International Working Group on DXA Best Practices

Osteoporotic fractures, also known as fragility fractures, are reflective of compromised bone strength and are associated with significant morbidity and mortality. Such fractures may be clinically silent, and others may present clinically with pain and deformity at the time of the injury. Unfortunately, and even at the time of detection, most individuals sustaining fragility fractures are not identified as having underlying metabolic bone disease and are not evaluated or treated to reduce the incidence of future fractures. A multidisciplinary international working group with representation from international societies dedicated to advancing the care of patients with metabolic bone disease has developed best practice recommendations for the diagnosis and evaluation of individuals with fragility fractures. A comprehensive narrative review was conducted to identify key articles on fragility fractures and their impact on the incidence of further fractures, morbidity, and mortality. This document represents consensus among the supporting societies and harmonizes best practice recommendations consistent with advances in research. A fragility fracture in an adult is an important predictor of future fractures and requires further evaluation and treatment of the underlying osteoporosis. It is important to recognize that most fragility fractures occur in patients with bone mineral density T scores higher than -2.5, and these fractures confirm the presence of skeletal fragility even in the presence of a well-maintained bone mineral density. Fragility fractures require further evaluation with exclusion of contributing factors for osteoporosis and assessment of clinical risk factors for fracture followed by appropriate pharmacological intervention designed to reduce the risk of future fracture. Because most low-trauma vertebral fractures do not present with pain, dedicated vertebral imaging and review of past imaging is useful in identifying fractures in patients at high risk for vertebral fractures. Given the importance of fractures in confirming skeletal fragility and predicting future events, it is recommended that an established classification system be used for fracture identification and reporting.

Pregnancy and lactation-associated osteoporosis as a major type of premenopausal osteoporosis: a retrospective cohort study based on real-world data

BACKGROUND

Pregnancy and lactation-associated osteoporosis (PLO), as well as premenopausal osteoporosis, might be a predictor of future fracture. This study aimed to describe the clinical features of PLO as a subtype of premenopausal osteoporosis and to evaluate medical interventions for it.

METHODS

From an administrative claims database including 4,224,246 people in Japan, we classified women for whom the date of childbirth had been defined and who had suffered low-trauma fracture between the ages of 18-47 years as the premenopausal osteoporosis group. A fracture site for which the odds ratio for fractures occurring between 5 months before and 12 months after childbirth (around childbirth) was greater than 1 was considered the PLO site. We classified patients with a fracture at the PLO site around childbirth as the PLO group. The control group consisted of 500 women without fragility fractures. We investigated some drugs and diseases to explore fracture-causing factors, as well as medical interventions such as osteoporosis diagnosis, bone densitometry, anti-osteoporosis pharmacotherapy, and lactation inhibitors.

RESULTS

In total, 231 parous women were classified into the premenopausal osteoporosis group. The most common fracture was vertebral fracture and was likely to occur around childbirth, followed by distal radius and sacral fractures, which were rare around childbirth. Considering vertebral, pelvic, and proximal femoral fractures as PLO sites, 56 women with 57 PLO fractures were classified into the PLO group. The incidence of PLO was estimated at 460 per million deliveries. Ovulation disorder and high maternal age were associated with the development of PLO. Vertebral fracture was the most common PLO fracture. It was mainly diagnosed a few months, and possibly up to 1 year, postpartum. PLO patients with vertebral fractures underwent more medical interventions than did those with other fractures, but they were still inadequate.

CONCLUSIONS

PLO with vertebral fracture was one of the major types of premenopausal osteoporosis. The prevalence of PLO is considered to be higher than previously thought, indicating the presence of potentially overlooked patients. More timely interventions for PLO might lead to the improved management of latent patients with premenopausal osteoporosis and reduce future fracture risk.

Association between body fat and bone mineral density in Korean adults: a cohort study

Although obesity was once considered protective against osteoporosis, various factors influence the relationship between fat and bone mineral density (BMD). To establish the importance of healthy body composition in decelerating declines in BMD, we conducted a study to compare the association between body fat composition and BMD in Korean adults. Using data collected from the Kangbuk Samsung Health Study from 2012 to 2019, this cohort study compared the incidence of decreased BMD among the following four groups: normal BMI and normal adiposity (NBMI-NA), normal BMI and high adiposity (NBMI-HA), overweight, and obesity. Decreased BMD was defined as a Z-score ≤  - 2.0 in premenopausal women and men < 50 years of age or a T-score <  - 1.0 in postmenopausal women and men ≥ 50 years of age. Individuals who were diagnosed with osteoporosis or compression fracture after their second visit were categorized as having decreased BMD. The incidence rate of decreased BMD in the NBMI-NA group was 3.37, and that in the NBMI-HA group was 4.81, which was the highest among all groups. After adjusting for confounding factors, NBMI-HA led to a significantly greater risk of decreased BMD compared to NBMI-NA (HR 1.47; 95% CI 1.09-1.99). Even with a normal BMI, a high BFP was associated with an increased risk of decreased BMD. Therefore, healthy body composition management, not simply BMI, is important in preventing decreased BMD.

Osteoporosis care through an Integrated, People-Centred Health Services framework lens: a hybrid qualitative analysis of international patient experiences

OBJECTIVES

Globally, patients with osteoporosis have unmet needs in terms of care accessibility, patient-centredness and care comprehensiveness. The WHO developed the Integrated, People-Centred Health Services (IPCHS) framework to reorient and integrate healthcare systems using 5 interdependent strategies and 20 substrategies. Patients' perspectives with regard to these strategies are poorly understood. We sought to relate patient-experienced gaps in osteoporosis care to the IPCHS strategies and identify key strategies to guide osteoporosis care reforms.

DESIGN, SETTING AND PARTICIPANTS

Qualitative online study of the experiences of international patients with osteoporosis.

PROCEDURE

Two researchers conducted semi-structured interviews in English, Dutch, Spanish and French that were recorded and transcribed verbatim. Patients were categorised according to their countries' healthcare systems (universal, public/private and private) and fracture status. A hybrid (sequential theory-driven and data-driven) analysis was performed, with the IPCHS framework used for the theory-driven analysis.

RESULTS

Thirty-five patients (33 women) from 14 countries participated. Twenty-two patients had universal healthcare and 18 had experienced fragility fractures. Prioritised substrategies overlapped among healthcare systems, with reported shortcomings related primarily to 'empowering and engaging individuals and families' and 'coordinating care' (at varying levels). Patients with all healthcare types prioritised 'reorienting care', with different substrategies prioritised. Patients with private healthcare called for 'improving funding and reforming payment systems'. Substrategy prioritisation did not differ between those receiving primary and secondary fracture prevention.

CONCLUSION

Patients' experiences with osteoporosis care are universal. Given the current care gaps and associated patient burdens, policymakers should make osteoporosis a(n) (inter)national health priority. Integrated osteoporosis care reforms should focus on patient-reported experiences with and be guided by priorities in IPCHS strategies, taking into account the healthcare system context.

Minocycline-induced disruption of the intestinal FXR/FGF15 axis impairs osteogenesis in mice

Antibiotic-induced shifts in the indigenous gut microbiota influence normal skeletal maturation. Current theory implies that gut microbiota actions on bone occur through a direct gut/bone signaling axis. However, our prior work supports that a gut/liver signaling axis contributes to gut microbiota effects on bone. Our purpose was to investigate the effects of minocycline, a systemic antibiotic treatment for adolescent acne, on pubertal/postpubertal skeletal maturation. Sex-matched specific pathogen-free (SPF) and germ-free (GF) C57BL/6T mice were administered a clinically relevant minocycline dose from age 6-12 weeks. Minocycline caused dysbiotic shifts in the gut bacteriome and impaired skeletal maturation in SPF mice but did not alter the skeletal phenotype in GF mice. Minocycline administration in SPF mice disrupted the intestinal farnesoid X receptor/fibroblast growth factor 15 axis, a gut/liver endocrine axis supporting systemic bile acid homeostasis. Minocycline-treated SPF mice had increased serum conjugated bile acids that were farnesoid X receptor (FXR) antagonists, suppressed osteoblast function, decreased bone mass, and impaired bone microarchitecture and fracture resistance. Stimulating osteoblasts with the serum bile acid profile from minocycline-treated SPF mice recapitulated the suppressed osteogenic phenotype found in vivo, which was mediated through attenuated FXR signaling. This work introduces bile acids as a potentially novel mediator of gut/liver signaling actions contributing to gut microbiota effects on bone.

Effects of vitamin D supplementation during pregnancy on bone health and offspring growth: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Whether vitamin D supplementation during pregnancy is beneficial to bone health and offspring growth remains controversial. Moreover, there is no universal agreement regarding the appropriate dose and the time of commencement of vitamin D supplementation during pregnancy.

OBJECTIVE

We aimed to systematically review the effects of vitamin D supplementation during pregnancy on bone development and offspring growth.

METHODS

A literature search for randomized controlled trials (RCTs) was performed in 7 electronic databases to identify relevant studies about the effects of vitamin D supplementation during pregnancy on bone development and offspring growth from inception to May 22, 2022. A Cochrane Risk Assessment Tool was used for quality assessment. Vitamin D supplementation was compared with placebo or standard supplements. The effects are presented as the mean differences (MDs) with 95% CIs. The outcomes include bone mineral content (BMC), bone mineral density (BMD), bone area (BA), femur length (FL) and humeral length (HL); measurement indicators of growth, including length, weight and head circumference; and secondary outcome measures, including biochemical indicators of bone health, such as the serum 25(OH)D concentration. Additionally, subgroup analyses were carried out to evaluate the impact of different doses and different initiation times of supplementation with vitamin D.

RESULTS

Twenty-three studies with 5390 participants met our inclusion criteria. Vitamin D supplementation during pregnancy was associated with increased humeral length (HL) (MD 0.13, 95% CI 0.06, 0.21, I2 = 0, P = 0.0007) during the fetal period (third trimester). Vitamin D supplementation during pregnancy was associated with a significantly increased length at birth (MD 0.14, 95% CI 0.04, 0.24, I2 = 24%, P = 0.005) and was associated with a higher cord blood 25(OH)D concentration (MD 48.74, 95% CI 8.47, 89.01, I2 = 100%, P = 0.02). Additionally, subgroup analysis revealed that birth length was significantly higher in the vitamin D intervention groups of ≤1000 IU/day and ≥4001 IU/day compared with the control group. Prenatal (third trimester) vitamin D supplementation was associated with a significant increase in birth length, while prenatal (second trimester) vitamin D supplementation was associated with a significant increase in birth weight.

CONCLUSION

Vitamin D supplementation during pregnancy may be associated with increased humeral length (HL) in the uterus, increased body length at birth and higher cord blood 25(OH)D concentration. Evidence of its effect on long-term growth in children is lacking. Additional rigorous high-quality, long-term and larger randomized trials are required to more fully investigate the effects of vitamin D supplementation during pregnancy.

Dietary nitrate and brain health. Too much ado about nothing or a solution for dementia prevention?

Dementia is a significant public health priority with approximately 55 million cases worldwide, and this number is predicted to quadruple by 2050. Adherence to a healthy diet and achieving optimal nutritional status are vital strategies to improve brain health. The importance of this area of research has been consolidated into the new term ‘nutritional psychiatry’. Dietary nitrate, closely associated with the intake of fruits and vegetables, is a compound that is increased in dietary patterns such as the Mediterranean and MIND diets and has protective effects on cognition and brain health. Nitrate is characterised by a complex metabolism and is the precursor of the nitrate–nitrite–nitric oxide (NO) pathway contributing to systemic NO generation. A higher intake of dietary nitrate has been linked to protective effects on vascular outcomes including blood pressure and endothelial function. However, the current evidence supporting the protective effects of dietary nitrate on brain health is less convincing. This article aims to provide a critical appraisal of the current evidence for dietary nitrate supplementation for improving brain health and provide suggestions for future research.

Osteoporosis in 2022: Care gaps to screening and personalised medicine

Osteoporosis care has evolved markedly over the last 50 years, such that there are now an established clinical definition, validated methods of fracture risk assessment, and a range of effective pharmacological agents. However, it is apparent that both in the context of primary and secondary fracture prevention, there is a considerable gap between the population at high fracture risk and those actually receiving appropriate antiosteoporosis treatment. In this narrative review article, we document recent work describing the burden of disease, approaches to management, and service provision across Europe, emerging data on gaps in care, and existing/new ways in which these gaps may be addressed at the level of healthcare systems and policy. We conclude that although the field has come a long way in recent decades, there is still a long way to go, and a concerted, integrated effort is now required from all of us involved in this field to address these urgent issues to ensure the best possible outcomes for our patients.

Bone Mass Accrual in First Six Months of Life: Impact of Maternal Diabetes, Infant Adiposity, and Cord Blood Adipokines

The perinatal period is a time of substantial bone mass accrual with many factors affecting long-term bone mineralization. Currently it is unclear what effect maternal gestational/type 2 diabetes has on infant bone mass accrual. This is a prospective study of offspring of Native American and Hispanic mothers with normoglycemia (n = 94) and gestational diabetes or type 2 diabetes (n = 64). Infant anthropometrics were measured at birth, 1, and 6 months of age. Cord blood leptin, high-molecular weight adiponectin (HMWA), pigment epithelium-derived factor (PEDF), vascular epithelium growth factor (VEGF), endoglin, and C-peptide were measured by ELISA. Infants had bone mineral density measurement at 1 month or/and 6 months of age using dual-energy x-ray absorptiometry scan. Mothers with diabetes were older (31 ± 6 years vs 25 ± 4 years) and had higher pre-pregnancy BMI (32.6 ± 5.8 vs 27.2 ± 6.4 kg/m²) than control mothers. Mean HbA1C of mothers with diabetes was 5.9 ± 1.0% compared to 5.1 ± 0.3% in controls early in pregnancy. Infants born to mothers with diabetes (DM-O) were born at a slightly lower gestational age compared to infants born to control mothers (Con-O). There was no difference in total body less head bone mineral content (BMC) or bone mineral density (BMD) between DM-O and Con-O. For both groups together, bone area, BMD, and BMC tracked over the first 6 months of life (r: 0.56, 0.38, and 0.48, respectively). Percent fat was strongly and positively correlated with BMC at 1 month of age (r = 0.44; p < 0.001) and BMC at both 1 and 6 months of age correlated strongly with birth weight. There were no associations between infant bone mass and cord blood leptin, PEDF, or VEGF, while C-peptide had a significant correlation with BMC at 1 and 6 months only in DM-O (p = 0.01 and 0.03, respectively). Infants born to mothers with well-controlled gestational/type 2 diabetes have normal bone mass accrual. Bone mineral content during this time is highly correlated with indices of infant growth and the association of bone mineral indices with percent body fat suggests that bone-fat crosstalk is operative early in life.

Associations Between Late Pregnancy Dietary Inflammatory Index (DII) and Offspring Bone Mass: A Meta-Analysis of the Southampton Women's Survey (SWS) and the Avon Longitudinal Study of Parents and Children (ALSPAC)

Systemic inflammation is associated with reduced bone mineral density and may be influenced by pro-inflammatory diets. We undertook an observational analysis of associations between late pregnancy energy-adjusted dietary inflammatory index (E-DII) scores and offspring bone outcomes in childhood. E-DII scores (higher scores indicating pro-inflammatory diets) were derived from food frequency questionnaires in late pregnancy in two prospective mother-offspring cohorts: the Southampton Women's Survey (SWS) and the Avon Longitudinal Study of Parents and Children (ALSPAC). The mean (SD) offspring age at dual-energy X-ray absorptiometry (DXA) scanning was 9.2 (0.2) years. Linear regression was used to assess associations between E-DII and bone outcomes, adjusting for offspring sex and age at DXA and maternal age at childbirth, educational level, pre-pregnancy body mass index (BMI), parity, physical activity level, and smoking in pregnancy. Associations were synthesized using fixed-effect meta-analysis. Beta coefficients represent the association per unit E-DII increment. In fully adjusted models (total n = 5910) late pregnancy E-DII was negatively associated with offspring whole body minus head bone area (BA: β = -3.68 [95% confidence interval -6.09, -1.27] cm2 /unit), bone mineral content (BMC: β = -4.16 [95% CI -6.70, -1.62] g/unit), and areal bone mineral density (aBMD: β = -0.0012 [95% CI -0.0020, -0.0004] g.cm-2 /unit), but there was only a weak association with BMC adjusted for BA (β = -0.48 [95% CI -1.11, 0.15] g/unit) at 9 years. Adjustment for child height partly or, for weight, fully attenuated the associations. Higher late pregnancy E-DII scores (representing a more pro-inflammatory diet) are negatively associated with offspring bone measures, supporting the importance of maternal and childhood diet on longitudinal offspring bone health. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Pregnancy Vitamin D Supplementation and Childhood Bone Mass at Age 4 Years: Findings From the Maternal Vitamin D Osteoporosis Study (MAVIDOS) Randomized Controlled Trial

In the Maternal Vitamin D Osteoporosis Study (MAVIDOS) randomized trial, vitamin D supplementation in pregnancy did not lead to greater neonatal bone mass across the trial as a whole, but, in a prespecified secondary analysis by season of birth, led to greater neonatal bone mass among winter-born babies. Demonstrating persistence of this effect into childhood would increase confidence in a long-term benefit of this intervention. We investigated whether antenatal vitamin D supplementation increases offspring bone mineralization in early childhood in a prespecified, single-center follow-up of a double-blinded, multicenter, randomized controlled clinical trial based in the UK (MAVIDOS). A total of 1123 women in early pregnancy with a baseline 25-hydroxyvitamin D level 25-100 nmol/L from three research centers (2008-2014) were randomized to 1000 IU/d cholecalciferol or matched placebo from 14 weeks of gestation to delivery. Offspring born at the Southampton, UK research center were assessed at age 4 years (2013-2018). Anthropometry and dual-energy X-ray absorptiometry (DXA) were performed (yielding whole body less head [WBLH] bone mineral content [BMC], areal bone mineral density [aBMD], bone area [BA], and body composition). Of 723 children, 564 (78.0%) children attended the 4-year visit, 452 of whom had a useable DXA. Maternal vitamin D supplementation led to greater WBLH aBMD in the children compared with placebo (mean [95% confidence interval {CI}]: supplemented group: 0.477 (95% CI, 0.472-0.481) g/cm2; placebo group: 0.470 (95% CI, 0.466-0.475) g/cm2, p = 0.048). Associations were consistent for BMC and lean mass, and in age- and sex-adjusted models. Effects were observed across the whole cohort irrespective of season of birth. Maternal-child interactions were observed, with a greater effect size among children with low milk intake and low levels of physical activity. Child weight, height, and body mass index (BMI) were similar by maternal randomization group. These findings suggest a sustained beneficial effect of maternal vitamin D supplementation in pregnancy on offspring aBMD at age 4 years, but will require replication in other trials. © 2022 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Using linear and natural cubic splines, SITAR, and latent trajectory models to characterise nonlinear longitudinal growth trajectories in cohort studies

BACKGROUND

Longitudinal data analysis can improve our understanding of the influences on health trajectories across the life-course. There are a variety of statistical models which can be used, and their fitting and interpretation can be complex, particularly where there is a nonlinear trajectory. Our aim was to provide an accessible guide along with applied examples to using four sophisticated modelling procedures for describing nonlinear growth trajectories.

METHODS

This expository paper provides an illustrative guide to summarising nonlinear growth trajectories for repeatedly measured continuous outcomes using (i) linear spline and (ii) natural cubic spline linear mixed-effects (LME) models, (iii) Super Imposition by Translation and Rotation (SITAR) nonlinear mixed effects models, and (iv) latent trajectory models. The underlying model for each approach, their similarities and differences, and their advantages and disadvantages are described. Their application and correct interpretation of their results is illustrated by analysing repeated bone mass measures to characterise bone growth patterns and their sex differences in three cohort studies from the UK, USA, and Canada comprising 8500 individuals and 37,000 measurements from ages 5-40 years. Recommendations for choosing a modelling approach are provided along with a discussion and signposting on further modelling extensions for analysing trajectory exposures and outcomes, and multiple cohorts.

RESULTS

Linear and natural cubic spline LME models and SITAR provided similar summary of the mean bone growth trajectory and growth velocity, and the sex differences in growth patterns. Growth velocity (in grams/year) peaked during adolescence, and peaked earlier in females than males e.g., mean age at peak bone mineral content accrual from multicohort SITAR models was 12.2 years in females and 13.9 years in males. Latent trajectory models (with trajectory shapes estimated using a natural cubic spline) identified up to four subgroups of individuals with distinct trajectories throughout adolescence.

CONCLUSIONS

LME models with linear and natural cubic splines, SITAR, and latent trajectory models are useful for describing nonlinear growth trajectories, and these methods can be adapted for other complex traits. Choice of method depends on the research aims, complexity of the trajectory, and available data. Scripts and synthetic datasets are provided for readers to replicate trajectory modelling and visualisation using the R statistical computing software.

Epigenetic regulation of bone mass

Osteoporosis, characterised by low bone mass, poor bone structure, and an increased risk of fracture, is a major public health problem. There is increasing evidence that the influence of the environment on gene expression, through epigenetic processes, contributes to variation in BMD and fracture risk across the lifecourse. Such epigenetic processes include DNA methylation, histone and chromatin modifications and non-coding RNAs. Examples of associations with phenotype include DNA methylation in utero linked to maternal vitamin D status, and to methylation of target genes such as OPG and RANKL being associated with osteoporosis in later life. Epigenome-wide association studies and multi-omics technologies have further revealed susceptibility loci, and histone acetyltransferases, deacetylases and methylases are being considered as therapeutic targets. This review encompasses recent advances in our understanding of epigenetic mechanisms in the regulation of bone mass and osteoporosis development, and outlines possible diagnostic and prognostic biomarker applications.

Potential influences on optimizing long-term musculoskeletal health in children and adolescents with X-linked hypophosphatemia (XLH)

In recent years, much progress has been made in understanding the mechanisms of bone growth and development over a lifespan, including the crosstalk between muscle and bone, to achieve optimal structure and function. While there have been significant advances in understanding how to help improve and maintain bone health in normal individuals, there is limited knowledge on whether these mechanisms apply or are compromised in pathological states. X-linked hypophosphatemia (XLH) (ORPHA:89936) is a rare, heritable, renal phosphate-wasting disorder. The resultant chronic hypophosphatemia leads to progressive deterioration in musculoskeletal function, including impaired growth, rickets, and limb deformities in children, as well as lifelong osteomalacia with reduced bone quality and impaired muscle structure and function. The clinical manifestations of the disease vary both in presentation and severity in affected individuals, and many of the consequences of childhood defects persist into adulthood, causing significant morbidity that impacts physical function and quality of life. Intervention to restore phosphate levels early in life during the critical stages of skeletal development in children with XLH could optimize growth and may prevent or reduce bone deformities in childhood. A healthier bone structure, together with improved muscle function, can lead to physical activity enhancing musculoskeletal health throughout life. In adults, continued management may help to maintain the positive effects acquired from childhood treatment, thereby slowing or halting disease progression. In this review, we summarize the opinions from members of a working group with expertise in pediatrics, epidemiology, and bone, joint and muscle biology, on potential outcomes for people with XLH, who have been optimally treated from an early age and continue treatment throughout life.

Placental uptake and metabolism of 25(OH)vitamin D determine its activity within the fetoplacental unit

Pregnancy 25-hydroxyvitamin D [25(OH)D] concentrations are associated with maternal and fetal health outcomes. Using physiological human placental perfusion and villous explants, we investigate the role of the placenta in regulating the relationships between maternal 25(OH)D and fetal physiology. We demonstrate active placental uptake of 25(OH)D₃ by endocytosis, placental metabolism of 25(OH)D₃ into 24,25-dihydroxyvitamin D₃ and active 1,25-dihydroxyvitamin D [1,25(OH)₂D₃], with subsequent release of these metabolites into both the maternal and fetal circulations. Active placental transport of 25(OH)D₃ and synthesis of 1,25(OH)₂D₃ demonstrate that fetal supply is dependent on placental function rather than simply the availability of maternal 25(OH)D₃. We demonstrate that 25(OH)D₃ exposure induces rapid effects on the placental transcriptome and proteome. These map to multiple pathways central to placental function and thereby fetal development, independent of vitamin D transfer. Our data suggest that the underlying epigenetic landscape helps dictate the transcriptional response to vitamin D treatment. This is the first quantitative study demonstrating vitamin D transfer and metabolism by the human placenta, with widespread effects on the placenta itself. These data demonstrate a complex interplay between vitamin D and the placenta and will inform future interventions using vitamin D to support fetal development and maternal adaptations to pregnancy.

Differential relationships between parent-child DXA and pQCT bone measures: Results from the Southampton Women's Survey

AIM

To investigate the associations between indices of bone health in childhood and corresponding parental measures.

METHODS

The Southampton Women's Survey characterised 12,583 non-pregnant women aged 20-34 years; 3158 subsequently had singleton live births. In a subset, dual-energy X-ray absorptiometry (DXA) measurements of bone area (BA), bone mineral content (BMC) and areal bone mineral density (aBMD) lumbar spine and total hip were obtained in the parent/offspring (aged 8-9 years) trios. Another subset of children (aged 6-7 years), and their parents, had peripheral quantitative computed tomography (pQCT; 4% and 38% tibia) measures. Using multivariable linear regression we examined relationships between mother/father and offspring, adjusting for parental age, habitual walking speed and education; offspring age and sex; and the corresponding bone measure in the other parent (β-coefficients (95%CI) unit/unit for each bone measure).

RESULTS

Data were available for 260 trios with DXA and 99 with pQCT. There were positive associations for BA, BMC and aBMD between either parent and offspring. Mother-child associations were of greater magnitude than father-child; for example, mother-child aBMD (β = 0.26 g·cm-2/g·cm-2 (0.21,0.32)) and father-child aBMD (β = 0.16 g·cm-2/g·cm-2 (0.11,0.21)), P-difference in β = 0.007. In the subset with pQCT there was a positive association for mother-offspring 4% tibial total area (β = 0.33 mm2/mm2 (0.17,0.48)), but little evidence of a father-offspring association (β = -0.06 mm2/mm2 (-0.17,0.06)). In contrast offspring 38% cortical density was more strongly associated with this measure in fathers (β = 0.48 mg·cm-3/mg·cm-3 (0.15,0.82)) than mothers (β = 0.27 mg·cm-3/mg·cm-3 (-0.03,0.56)). In general mother-father differences were attenuated by adjustment for height.

CONCLUSIONS

Whilst offspring bone measures are independently associated with those of either parent, the magnitude of the association is often greater for maternal than paternal relationships. These findings are consistent with an in utero influence on offspring growth but might also reflect genetic and/or epigenetic parent of origin effects.

SUMMARY

In an established parent-offspring cohort, associations between parent and offspring bone indices were generally greater in magnitude for mother-offspring than father-offspring relationships.

Non-linear and non-additive associations between the pregnancy metabolome and birthweight

BACKGROUND

Birthweight is an indicator of fetal growth and environmental-related alterations of birthweight have been linked with multiple disorders and conditions progressing into adulthood. Although a few studies have assessed the association between birthweight and the totality of exogenous exposures and their downstream molecular responses in maternal urine and cord blood; no prior research has considered a) the maternal serum prenatal metabolome, which is enriched for hormones, and b) non-linear and synergistic associations among exposures.

METHODS

We measured the maternal serum metabolome during pregnancy using an untargeted metabolomics approach and birthweight for gestational age (BWGA) z-score in 410 mother-child dyads enrolled in the PRogramming of Intergenerational Stress Mechanisms (PRISM) cohort. We leveraged a Bayesian factor analysis for interaction to select the most important metabolites associated with BWGA z-score and to evaluate their linear, non-linear and non-additive associations. We also assessed the primary biological functions of the identified proteins using the MetaboAnalyst, a centralized repository of curated functional information. We compared our findings with those of a traditional metabolite-wide association study (MWAS) in which metabolites are individually associated with BWGA z-score.

RESULTS

Among 1110 metabolites, 46 showed evidence of U-shape associations with BWGA z-score. Most of the identified metabolites (85%) were lipids primarily enriched for pathways central to energy production, immune function, and androgen and estrogen metabolism, which are essential for pregnancy and parturition processes. Metabolites within the same class, i.e. steroids and phospholipids, showed synergistic relationships with each other.

CONCLUSIONS

Our results support that the aspects of the maternal metabolome during pregnancy contribute linearly, non-linearly and synergistically to variation in newborn birthweight.

Allulose Attenuated Age-Associated Sarcopenia via Regulating IGF-1 and Myostatin in Aged Mice

SCOPE

Allulose is shown to increase the muscle weight in diet-induced obese mice. However, there are no studies on the effects of allulose in age-associated sarcopenia. This study aims to elucidate the mechanisms of action for allulose in age associated by analyzing the transcriptional patterns in aged mice.

METHODS AND RESULTS

The 48-week-old mice are fed with AIN-93diet containing allulose for 12 weeks. Allulose supplementation increases the muscle mass and grip strength in aged mice. Allulose increases the insulin-like growth factor 1 (IGF-1) and its downstream factor expressions which 40 are related protein synthesis, while inhibits the myostatin expression related protein degradation. In mRNA-seq analysis, allulose supplementation significantly decreases in Adiponectin, Adipsin, cell death inducing DFFA like effector (CIDEC), Haptoglobin, Neuroglobin, and stearoyl-CoA desaturase-1 (SCD1) and increases in cytokine-inducible SH2-containing protein (CISH) and ceramide synthase 1 (CerS1) that are regulate protein turn over in gastrocnemius. Also, allulose alleviates autophagy in muscle with regulated mammalian target of rapamycin (mTOR) signaling pathway and increases the anti-oxidant enzyme activity.

CONCLUSION

These findings suggest that allulose improves the age-associated sarcopenia with enhancing antioxidant properties by altering mRNA and protein expression.

Effect of Eight-Month Exercise Intervention on Bone Outcomes of Young Opioid-Dependent Women

Objective: To evaluate the bone response to an 8 month aerobic gymnastics training program in young opioid-addicted women. Design: Randomized controlled trial (parallel design). Setting: Women’s Specific Drug Rehabilitation Center in China. Patients: One hundred and two young women with low bone quality and previous opioid addiction were divided into two groups: (a) the low bone quality intervention experimental group (n = 55; age: 30.3 ± 6.1) and (b) the low bone quality observed control group (observation group; n = 47; age: 29.0 ± 5.3). Interventions: The intervention group took aerobic gymnastics regularly for 80 min/d and 5 d/wk for 8 months and completed follow-up testing. Main Outcome Measures: Substance use history and other life habits affecting bone quality were assessed by questionnaire-based interviews. Bone quality (stiffness-index, T-score, Z-score) was examined with quantitative ultrasound. Anthropometric characteristics (body weight, fat-free mass, fat mass) were obtained by bioelectrical impedance analysis. Results: After the 8 month intervention, the stiffness index of bone quality increased significantly (before: 82 ± 6, after: 108 ± 14, p < 0.05) in the experimental group. However, the bone quality did not change significantly in the controls (before: 79 ± 10, after: 77 ± 13, p > 0.05). The bone change in the difference group was significant (experimental group: 31.7% vs observation group: -0.03%). Fat mass decreased in the experimental group (experimental group: before: 19.6 ± 3.7 kg, after: 18.8 ± 4.0 kg, p < 0.05). Meanwhile, the change in fat-free mass was the determination of the change in bone quality in the experimental group. Conclusions: Our results suggested that aerobic gymnastics intervention can be an effective strategy for the prevention and treatment of drug-induced osteoporosis in detoxification addicts.

Bone-Targeting Polymer Vesicles for Effective Therapy of Osteoporosis

With the aging of the population, postmenopausal osteoporosis becomes increasingly widespread and severe as fractures caused by osteoporosis may lead to permanent disabilities and even death. Inspired by extracellular vesicles that participate in bone remodeling, we present a biomimicking polymer vesicle for bone-targeted β-estradiol (E₂) delivery. This vesicle is self-assembled from a poly(ε-caprolactone)₂₈-block-poly[(l-glutamic acid)₇-stat-(l-glutamic acid-alendronic acid)₄] (PCL₂₈-b-P[Glu₇-stat-(Glu-ADA)₄]) diblock copolymer. The alendronic acid (ADA) on the coronas endows the polymer vesicles with a high bone affinity and acts synergistically with E₂ to achieve an enhanced therapeutic effect. As confirmed with ovariectomized osteoporosis rat models, bone loss was significantly reversed as the recovery rates of total BMD (bone mineral density) and trabecular BMD were 70.4% and 99.3%, respectively. Overall, this work provides fresh insight into the treatment of osteoporosis.

Impact of population-based or targeted BMD interventions on fracture incidence

In a simulated population of older women, we demonstrate that an upward shift in the population distribution of BMD by approximately 0.3SD may decrease the risk of incident fractures to the same extent as an intervention targeted to those with T-score less than -2.5.

INTRODUCTION

To investigate the impact of population level or targeted alterations to BMD on the incidence of fractures.

METHODS

We used a simulated cohort of 49,242 women with age and body mass index distribution from the UK, and prevalence of other clinical risk factors based on European FRAX® cohorts. Using FRAX probabilities of major osteoporotic fracture (MOF: hip, clinical vertebral, distal forearm, proximal humerus) and hip fracture, calculated with femoral neck BMD, we determined the expected number of fractures over 10 years, stratified by 10-year age band from 50 years. We then investigated the effect of (i) uplifting all individuals with T-score below -2.5 to be exactly -2.5 (high-risk strategy) and (ii) shifting the entire BMD distribution upwards (population strategy).

RESULTS

Overall, the high-risk strategy prevented 573 MOF including 465 hip fractures. Moving the BMD T-score distribution upward by 0.27SD gave an equivalent reduction in numbers of MOF; for hip fractures prevented, this was 0.35SD. A global upward 0.25SD BMD shift prevented 524 MOF including 354 hip fractures, with corresponding figures for an increase of 0.5SD being 973 MOF prevented and 640 hip fractures prevented. The ratio of hip fracture to MOF prevented differed by the two approaches, such that for the high-risk strategy, the ratio was 0.81, and for the population strategy was 0.68 (0.25SD BMD uplift) and 0.66 (0.5SD BMD uplift). The numbers of fractures prevented by the high-risk strategy increased with age. In contrast, the age-related increase in numbers of fractures prevented with the population strategy rose with age, but peaked in the 70-79-year age band and declined thereafter.

CONCLUSIONS

Both strategies reduced the numbers of expected incident fractures, with contrasting relative impacts by age and fracture site. Whilst the current analysis used UK/European anthropometric/risk factor distributions, further analyses calibrated to the distributions in other settings globally may be readily undertaken. Overall, these findings support the investigation of both population level interventions and those targeted at high fracture risk groups.

A Distinctive Human Metabolomics Alteration Associated with Osteopenic and Osteoporotic Patients

Osteoporosis is a common progressive metabolic bone disease resulting in decreased bone mineral density (BMD) and a subsequent increase in fracture risk. The known bone markers are not sensitive and specific enough to reflect the balance in the bone metabolism. Finding a metabolomics-based biomarker specific for bone desorption or lack of bone formation is crucial for predicting bone health earlier. This study aimed to investigate patients' metabolomic profiles with low BMD (LBMD), including those with osteopenia (ON) and osteoporosis (OP), compared to healthy controls. An untargeted mass spectrometry (MS)-based metabolomics approach was used to analyze serum samples. Results showed a clear separation between patients with LBMD and control (Q² = 0.986, R² = 0.994), reflecting a significant difference in the dynamic of metabolic processes between the study groups. A total of 116 putatively identified metabolites were significantly associated with LBMD. Ninety-four metabolites were dysregulated, with 52 up- and 42 downregulated in patients with LBMD compared to controls. Histidine metabolism, aminoacyl-tRNA biosynthesis, glyoxylate, dicarboxylate metabolism, and biosynthesis of unsaturated fatty acids were the most common metabolic pathways dysregulated in LBMD. Furthermore, 35 metabolites were significantly dysregulated between ON and OP groups, with 11 up- and 24 downregulated in ON compared to OP. Among the upregulated metabolites were 3-carboxy-4-methyl-5-propyl-2-2furanopropionic acid (CMPF) and carnitine derivatives (i.e., 3-hydroxy-11-octadecenoylcarnitine, and l-acetylcarnitine), whereas phosphatidylcholine (PC), sphingomyelin (SM), and palmitic acid (PA) were among the downregulated metabolites in ON compared to OP. This study would add a layer to understanding the possible metabolic alterations associated with ON and OP. Additionally, this identified metabolic panel would help develop a prediction model for bone health and OP progression.

miRNA Let-7a-5p targets RNA KCNQ1OT1 and Participates in Osteoblast Differentiation to Improve the Development of Osteoporosis

It is known that miRNA mediates the formation of osteogenesis, but the mechanism by which miRNA let-7a-5p regulates osteogenesis in osteoporosis (OP) is not yet understood. This paper aims to probe into the regulatory mechanism of miRNA let-7a-5p in the development of OP. Fresh femoral trabecular bones of patients with osteoporotic fracture (OP group, n = 25) and non-OP osteoarthritis (Non-OP group, n = 23) who underwent hip replacement in our hospital from December 2016 to December 2019 were collected. The expression and protein levels of miRNA let-7a-5p and V-AKT murine thymoma viral oncogene homolog 3 (RNA KCNQ1OT1) were detected. C2C12 cells were purchased and osteogenic differentiation model was constructed by BMP2 induction. After miRNA let-7a-5p up-regulation or down-regulation by transfection of corresponding mimics and inhibitors, the impacts of miRNA let-7a-5p and RNA KCNQ1OT1 on osteogenic differentiation-related factors (OC, ALP, COL1A1) in C2C12 cells were analyzed. The determination of targeting correlation of miRNA let-7a-5p with RNA KCNQ1OT1 was performed by dual-luciferase reporter (DLR). In OP samples, miRNA let-7a-5p was notably declined while RNA KCNQ1OT1 were remarkably up-regulated. MiRNA let-7a-5p reduced in C2C12 cells as BMP2 treatment proceeded. MiRNA let-7a-5p up-regulation or RNA KCNQ1OT1 down-regulation increased OC, ALP, COL1A1 levels and ALP activity. RNA KCNQ1OT1 was directly targeted to miR-497-5p. RNA KCNQ1OT1 up-regulation weakened the promoting effect of miRNA let-7a-5p up-regulation on osteoblast differentiation. MiRNA let-7a-5p up-regulation can target to reduce RNA KCNQ1OT1 and promote osteoblast differentiation, thereby improving the development of osteoporosis.

Maternal Diet, Nutritional Status, and Birth-Related Factors Influencing Offspring's Bone Mineral Density: A Narrative Review of Observational, Cohort, and Randomized Controlled Trials

There is growing evidence that bone health may be programmed in the first years of life. Factors during the prenatal period, especially maternal nutrition, may have an influence on offspring’s skeletal development and thus the risk of osteoporosis in further life, which is an increasing societal, health and economic burden. However, it is still inconclusive which early life factors are the most important and to what extent they may affect bone health. We searched through three databases (PubMed, Google Scholar, Cochrane Library) and after eligibility criteria were met, the results of 49 articles were analyzed. This narrative review is an overall summary of up-to-date studies on maternal diet, nutritional status, and birth-related factors that may affect offspring bone development, particularly bone mineral density (BMD). Maternal vitamin D status and diet in pregnancy, anthropometry and birth weight seem to influence BMD, however other factors such as subsequent growth may mediate these associations. Due to the ambiguity of the results in the analyzed studies, future, well-designed studies are needed to address the limitations of the present study.

Immune Markers and Their Association with Bone Density in Children, Adolescents, and Young Adults with Perinatally Acquired HIV

To describe distributions of immune markers in children and young adults by sex and HIV status, and within groups, investigate associations of immune markers with bone density across Tanner stage. Using data and samples from 353 participants in a cross-sectional study in youth with perinatally acquired HIV (PHIV) and matched HIV-negative controls, distributions of inflammation and activation immune markers were described by sex and HIV status. Correlations and structural equation models (SEM) were used to explore marginal and multivariable associations of the immune markers with bone density and to assess whether patterns of association varied by sex and HIV status. Immune marker distributions did not differ by sex, but there were some differences by HIV status. Correlation patterns among bone, body composition, and immune markers were similar across the sex and HIV status groups. Conclusions from SEMs were limited by small sample sizes, but there was some indication that patterns of association between bone density and certain immune markers differed in male PHIV with more advanced Tanner stage compared to the other three groups. In conclusion, distributions of bone density, body composition, and immune markers may vary by sex and HIV status, although associations among these outcomes within sex and HIV status groups appear similar. Bone density of male PHIV appears to be more negatively affected than females, regardless of female HIV status. Larger longitudinal studies across Tanner stages are needed to further explore potential biological relationships between immune markers and bone density in youth living with HIV.

Placental volume at 11 weeks is associated with offspring bone mass at birth and in later childhood: Findings from the Southampton Women's Survey

OBJECTIVES

To investigate associations between placental volume (PV) at 11 weeks' gestation and offspring bone outcomes at birth, 6 years and 8 years.

METHODS

3D ultrasound scanning was used to assess 11 week PV in a subset (n = 236) of the Southampton Women's Survey (a prospective mother-offspring cohort). Maternal anthropometric measures and lifestyle information were obtained pre-pregnancy and at 11 weeks' gestation. Offspring dual-energy x-ray absorptiometry scanning was performed within 2 weeks postnatally and at 6 and 8 years. Linear regression was used to assess associations between PV and bone outcomes, adjusting for offspring age at DXA and sex, and maternal age, height, smoking status, walking speed and triceps skinfold thickness. β are SD change in bone outcome per SD change in PV.

RESULTS

In adjusted models, 11 week PV was positively associated with bone area (BA) at all time points, with evidence of persisting associations with increasing childhood age (birth: n = 80, β = 0.23 [95%CI = 0.03, 0.42], 6 years: n = 110, β = 0.17 [-0.01, 0.36], 8 years: n = 85, β = 0.13 [-0.09, 0.36]). Similar associations between 11 week PV and bone mineral content (BMC) were observed. Associations with size-corrected bone mineral content were weaker at birth but strengthened in later childhood (birth: n = 78, β = 0.07 [-0.21, 0.35], 6 years: n = 107, β = 0.13 [-0.08, 0.34], 8 years: n = 71, β = 0.19 [-0.05, 0.43]).

CONCLUSIONS

11 week PV is associated with DXA bone measures at birth, with evidence of persisting associations into later childhood. Further work is required to elucidate the contributions of placental morphology and function to gestational influences on skeletal development.

Physical Activity Throughout Adolescence and Peak Hip Strength in Young Adults

IMPORTANCE

Peak bone strength, which occurs in early adulthood, is an important marker of the future risk of osteoporosis. It is therefore important to identify modifiable early life factors that are associated with the attainment of peak hip strength.

OBJECTIVE

To investigate the association of time spent in moderate to vigorous-intensity and light-intensity physical activity throughout adolescence with peak hip strength in adulthood.

DESIGN, SETTING, AND PARTICIPANTS

The Avon Longitudinal Study of Parents and Children is a prospective birth cohort study that initially recruited all pregnant women residing within the catchment area of 3 health authorities in southwest England who had an expected delivery date between April 1, 1991, and December 31, 1992. In total, 15 454 eligible pregnant women were enrolled, and 15 589 infants were delivered. Of those, 14 901 infants were alive at age 1 year. The present analysis examined 2569 healthy offspring who had valid physical activity measurements obtained during a clinical assessment for at least 1 age (12, 14, 16, and/or 25 years), with up to 4 repeated accelerometer assessments performed (1 per age-associated clinical visit). Data were analyzed from June 2019 to June 2020.

EXPOSURES

Trajectories of accelerometer-assessed time spent in moderate to vigorous-intensity and light-intensity physical activity at ages 12, 14, 16, and 25 years (measured in minutes per day) were identified using latent trajectory modeling. Moderate to vigorous-intensity and light-intensity physical activity were determined using established thresholds of acceleration counts per minute.

MAIN OUTCOMES AND MEASURES

Femur neck bone mineral density (BMD; measured in g/cm2) at age 25 years assessed by dual-energy radiography absorptiometry scans of the hip.

RESULTS

A total of 2569 participants (1588 female participants [62%]) were included in the analysis. Male participants spent more time in moderate to vigorous-intensity activity at each age and had greater adult femur neck BMD than female participants. For each sex, 3 moderate to vigorous-intensity trajectory subgroups and 3 light-intensity trajectory subgroups were identified. With regard to the moderate to vigorous-intensity trajectories, most male participants (85%) were in the low adolescent subgroup, with only 6% and 9% in the high early-adolescent and high mid-adolescent subgroups, respectively. Moderate to vigorous-intensity trajectories in female participants were divided into low adolescent-low adult (73%), low adolescent-high adult (8%), and high adolescent (19%) subgroups. Light-intensity physical activity trajectories were classified into low nonlinear, moderate decreasing, and high decreasing subgroups for both sexes. Femur neck BMD in male participants was greater in the high early-adolescent subgroup (0.38 g/cm2; 95% CI, 0.11-0.66 g/cm2) and the high mid-adolescent subgroup (0.33 g/cm2; 95% CI, 0.07-0.60 g/cm2) compared with the low adolescent (reference) subgroup. Femur neck BMD in female participants was greater in the high adolescent subgroup (0.28 g/cm2; 95% CI, 0.15-0.41 g/cm2) but not in the low adolescent-high adult subgroup (-0.12 g/cm2; 95% CI, -0.44 to 0.20 g/cm2) compared with the low adolescent-low adult (reference) subgroup. A sensitivity analysis using a negative-outcome control variable to explore unmeasured confounding supported these findings. The light-intensity trajectories were not associated with femur neck BMD; for example, differences in femur neck BMD between the high decreasing and low nonlinear subgroups were 0.16 g/cm2 (95% CI, -0.08 to 0.40 g/cm2) in male participants and 0.20 g/cm2 (95% CI, -0.05 to 0.44 g/cm2) in female participants.

CONCLUSIONS AND RELEVANCE

Supporting high-intensity physical activity throughout early life may help to maximize peak hip strength and prevent osteoporosis in later life. Replication of our findings in independent studies will be important.

Osteoporosis in Premenopausal Women: A Clinical Narrative Review by the ECTS and the IOF

CONTEXT

Consensus regarding diagnosis and management of osteoporosis in premenopausal women (PW) is still lacking due to few studies carried out in this population.

DESIGN

The European Calcified Tissue Society and the International Osteoporosis Foundation convened a working group to produce an updated review of literature published after 2017 on this topic.

RESULTS

Fragility fractures in PW are rare and mostly due to secondary osteoporosis (ie, in presence of an underlying disease such as hormonal, inflammatory, or digestive disorders). In absence of another disorder, low bone mineral density (BMD) together with fragility fractures qualifies as idiopathic osteoporosis. In contrast, low BMD alone does not necessarily represent osteoporosis in absence of bone microarchitectural abnormalities. BMD increases in PW with osteoporosis when the underlying disease is treated. For example, in celiac disease, an increase of 9% in radius trabecular volumetric density was achieved after 1 year of gluten-free diet, while anti-tumor necrosis factor alpha improved BMD in PW with inflammatory bowel diseases. In amenorrhea, including anorexia nervosa, appropriately delivered estrogen replacement therapy can also improve BMD. Alternatively, antiresorptive or anabolic therapy has been shown to improve BMD in a variety of conditions, the range of improvement (3%-16%) depending on skeletal site and the nature of the secondary cause. No studies were powered to demonstrate fracture reduction. The effects of bisphosphonates in childbearing women have been scantly studied and caution is needed.

CONCLUSION

The majority of PW with osteoporosis have an underlying disease. Specific therapy of these diseases, as well as antiresorptive and anabolic drugs, improve BMD, but without evidence of fracture reduction.

Sustained Release of Melatonin from GelMA Liposomes Reduced Osteoblast Apoptosis and Improved Implant Osseointegration in Osteoporosis

A reduction in bone mass around an implant is the main cause of implant loosening, especially in postmenopausal osteoporosis patients. In osteoporosis, excessive oxidative stress, resulting in osteoblast apoptosis, largely contributes to abnormal bone remodeling. Melatonin (MT) synthesized by the pineal gland promotes osteoblast differentiation and bone formation and has been effectively used to combat oxidative stress. Therefore, we hypothesized that MT attenuates osteoblast apoptosis induced by oxidative stress, promotes osteogenesis in osteoporosis, and improves bone mass around prostheses. Moreover, considering the distribution and metabolism of MT, its systemic administration would require a large amount of MT, increasing the probability of drug side effects, so the local administration of MT is more effective than its systemic administration. In this study, we constructed a composite adhesive hydrogel system (GelMA-DOPA@MT) to bring about sustained MT release in a local area. Additionally, MT-reduced apoptosis caused by hydrogen peroxide- (H₂O₂-) induced oxidative stress and restored the osteogenic potential of MC3T3-E1 cells. Furthermore, apoptosis in osteoblasts around the implant was significantly attenuated, and increased bone mass around the implant was observed in ovariectomized (OVX) rats treated with this composite system. In conclusion, our results show that GelMA-DOPA@MT can inhibit osteoblast apoptosis caused by oxidative stress, thereby promoting osteogenesis and improving bone quality around a prosthesis. Therefore, this system of local, sustained MT release is a suitable candidate to address implant loosening in patients with osteoporosis.

Synthesis and biological activities of drugs for the treatment of osteoporosis

Osteoporosis is an asymptomatic progressive disease. With the improvement of people's living standard and the aging of population, osteoporosis and its fracture have become one of the main diseases threatening the aging society. The serious medical and social burden caused by this has aroused wide public concern. Osteoporosis is listed as one of the three major diseases of the elderly. At present, the drugs for osteoporosis include bone resorption inhibitors and bone formation promoters. The purpose of these anti-osteoporosis drugs is to balance osteoblast bone formation and osteoclast bone resorption. With the development of anti-osteoporosis drugs, new anti osteoporosis drugs have been designed and synthesized. There are many kinds of new compounds with anti osteoporosis activity, but most of them are concentrated on the original drugs with anti osteoporosis activity, or the natural products with anti-osteoporosis activity are extracted from the natural products for structural modification to obtain the corresponding derivatives or analogues. These target compounds showed good ALP activity in vitro and in vivo, promoted osteoblast differentiation and mineralization, or had anti TRAP activity, inhibited osteoclast absorption. This work attempts to systematically review the studies on the synthesis and bioactivity of anti-osteoporosis drugs in the past 10 years. The structure-activity relationship was discussed, which provided a reasonable idea for the design and development of new anti-osteoporosis drugs.

Growth from birth to adolescence and bone mineral density in young adults: The 1993 Pelotas birth cohort

BACKGROUND

The study examined the association of body size (weight and length) at birth and gain in height and weight during childhood and adolescence with areal bone mineral density (aBMD) in adulthood for women and men.

METHODS

756 members (335 men and 421 women) of the 1993 Pelotas (Brazil) Birth cohort were studied. Data on weight and length/height were obtained at birth and subsequent follow-ups at 1, 4, 11, 15, 18, and 22 years of age and specific z scores were calculated by sex. The outcome was whole body aBMD (g/cm²) measured at 22 years of age using dual-energy X-ray absorptiometry (DXA). The effects of exposures, weight and length/height gain, were analyzed using conditional relative weight (CWh) and conditional length/height (CH). Linear regression models were adjusted for multiple confounders, including mother's educational level, family income, maternal smoking during pregnancy, gestational age, breastfeeding and skin color.

RESULTS

In the adjusted models, among men greater height gain at 4, 11, and 18 years of age was associated with higher whole body aBMD, and the result with greatest magnitude was at 11 years of age (β 0.018 g/cm²; 95%CI 0.006; 0.030). Among women, aBMD was associated with height gain at all assessments from 1-15 years, with greatest effect size at 4 years of age (β 0.017 g/cm²; 95%CI 0.007; 0.027). Regarding to body weight, among men, greater weight at 4 and 15 years were associated with higher aBMD, with the highest coefficients for 15 years of age (β 0.015 g/cm²; 95%CI 0.003; 0.027); for women, except at birth, all weight gain variables were associated with aBMD and the highest coefficients were observed at 4 years (β 0.025 g/cm²; 95%CI 0.015; 0.035).

CONCLUSIONS

In this birth cohort, height and weight gain, especially from 4 to 15 years have important positive implications for aBMD to early adulthood.

MiR-152 influences osteoporosis through regulation of osteoblast differentiation by targeting RICTOR

Context: Evidence suggests that microRNA (miRNA) regulate gene expression and bone tissue homoeostasis of osteoporosis. MiR-152 has found to be abnormally expressed in osteoporosis, but its role in osteoblast differentiation has not been elucidated. Objective: To understand the potential mechanism of miR-152 in osteoblast differentiation via regulation of RICTOR. Materials and methods: The expression of miR-152 and RICTOR were tested in ovariectomized rat models of osteoporosis. Primary osteoblasts and MC3T -E1 cells were assigned into four groups, namely Control, miR-152 inhibitor, miR-control and miR-152 inhibitor + siRICTOR groups. qRT PCR and Western blot were performed to detect the expressions of miR-152 and RICTOR, respectively. MTT assay was used to evaluate cell viability, and ALP activity determination and mineralization analyses were also conducted. Results: In ovariectomy-induced osteoporotic rats, miR-152 (3.06 ± 0.35) in femoral tissues increased significantly, while RICTOR (0.31 ± 0.04) decreased. Compared with Control group, miR-152 inhibitor group presented appreciable reduction of miR-152 in primary osteoblasts and MC3T3-E1 cells, as well as remarkable increases in RICTOR, p-Akt(s473)/Akt ratio, and osteogenesis-related genes, with enhanced cell viability, ALP activity and mineralization. In comparison with cells in the miR-152 inhibitor group, those in the miR-152 inhibitor + siRICTOR group had no observable difference in miR-152, but were dramatically up-regulated in RICTOR, as well as the corresponding opposite tendencies of other factors. Conclusion: Inhibiting miR-152 promoted osteoblasts differentiation and alleviated osteoporosis by up-regulating RICTOR. Therefore, miR-152 may be an essential mediator of osteoblast differentiation and a new therapeutic strategy for osteoporosis.

Association Between Age at Puberty and Bone Accrual From 10 to 25 Years of Age

Importance

Bone health in early life is thought to influence the risk of osteoporosis in later life.

Objective

To examine whether puberty timing is associated with bone mineral density accrual up to adulthood.

Design, Setting, and Participants

This cohort study used data from the Avon Longitudinal Study of Parents and Children, a prospective population-based birth cohort initiated in 1991 to 1992 in southwest England. The participants were 6389 healthy British people who underwent regular follow-up, including up to 6 repeated bone density scans from ages 10 to 25 years. Data analysis was performed from June 2018 to June 2019.

Exposures

Age at puberty from estimated age at peak height velocity (years).

Main Outcomes and Measures

Gains per year in whole-body bone mineral density (grams per square centimeter), assessed by dual-energy x-ray absorptiometry at ages 10, 12, 14, 16, 18, and 25 years and modeled using linear splines.

Results

A total of 6389 participants (3196 [50.0%] female) were included. The mean (SD) age at peak height velocity was 13.5 (0.9) years for male participants and 11.6 (0.8) years for female participants. Male participants gained bone mineral density at faster rates than did female participants, with the greatest gains in both male participants (0.139 g/cm2/y; 95% CI, 0.127-0.151 g/cm2/y) and female participants (0.106 g/cm2/y; 95% CI, 0.098-0.114 g/cm2/y) observed between the year before and 2 years after peak height velocity. When aligned by chronological age, per 1-year older age at puberty was associated with faster subsequent gains in bone mineral density; the magnitudes of faster gains were greatest between ages 14 and 16 years in both male participants (0.013 g/cm2/y; 95% CI, 0.011-0.015 g/cm2/y) and female participants (0.014 g/cm2/y; 95% CI, 0.014-0.015 g/cm2/y), were greater in male participants (0.011 g/cm2/y; 95% CI, 0.010-0.013 g/cm2/y) than in female participants (0.003 g/cm2/y; 95% CI, 0.003-0.004 g/cm2/y) between ages 16 and 18 years, and were least in both male participants (0.002 g/cm2/y; 95% CI, 0.001-0.003 g/cm2/y) and female participants (0.000 g/cm2/y; 95% CI, -0.001 to 0.000 g/cm2/y) between ages 18 and 25 years. Despite faster gains, older age at puberty was associated with persistently lower bone mineral density, changing from 0.050 g/cm2 (95% CI, -0.056 to -0.045 g/cm2) lower at age 14 years to 0.047 g/cm2 (95% CI, -0.051 to -0.043 g/cm2) lower at age 25 years in male participants and from 0.044 g/cm2 (95% CI, -0.046 to -0.041 g/cm2) to 0.034 g/cm2 (95% CI, -0.036 to -0.032 g/cm2) lower at the same ages in female participants.

Conclusions and Relevance

People with older pubertal age should be advised on how to maximize bone mineral density and minimize its decrease in later life to help prevent fracture and osteoporosis.

Maternal vitamin D in pregnancy and offspring bone measures in childhood: The Vitamin D in Pregnancy study

Previously we have demonstrated an association between maternal serum 25-hydroxyvitamin D (25(OH)D) during pregnancy and knee-heel length in offspring at birth. However, it is unknown whether maternal serum 25(OH)D is associated with bone measures in childhood. Thus, we aimed to examine associations between 25(OH)D at two stages of pregnancy and offspring bone measures at 11 years. Women were recruited from a single antenatal clinic in Victoria, Australia before 16 weeks gestation and provided two serum samples to determine 25(OH)D status at recruitment and 28-32 weeks gestation. Children and their mothers were followed up at 11 years of age. Children undertook dual energy X-ray absorptiometry scans at the lumbar spine and total body. Maternal 25(OH)D at recruitment (before 16 weeks gestation) was positively associated with the children's bone mineral content and density in boys, but not girls. In boys, a 10 nmol/L (4 ng/mL) increase in maternal 25(OH)D was associated with a median 0.5 g (95% CI 0.1,0.8) and 0.009 g/cm² (95% CI 0.001,0.017) increase in bone mineral content and density at the spine, respectively, and a median 0.006 g/cm² (95% CI 0.001,0.011) increase in at the total body. There was no sustained associations with 25(OH)D at the later timepoint (28-32 weeks) with any outcome. At age 11 years, maternal 25(OH)D levels during early pregnancy, but not late were positively associated with bone measures in boys, but not girls.

Prenatal influences on bone health in children

INTRODUCTION

Optimising bone health might reduce the burden of both fractures in childhood and fragility fractures in later life. A number of maternal dietary and non-dietary factors have been identified that might influence offspring bone health and represent targets for intervention.

AREAS COVERED

This article will outline the accrual of bone mineral throughout the life course and how observational and intervention studies have shown that maternal diet, in particular maternal calcium and 25-hydroxyvitamin D [25(OH)D] status, and lifestyle are associated with offspring bone mineralization. Studies examining the effects of maternal micronutrient supplementation on offspring bone mineral density (BMD) will also be discussed.

EXPERT COMMENTARY

There is a wealth of observational evidence relating maternal diet to offspring BMD. However, high quality randomized controlled trials, such as the ongoing MAVIDOS study, are needed before these findings can be definitively translated into public health advice.

The role of DNA methylation in the disorders of bone metabolism

Osteoporosis is one of multifactorial diseases, it develops from interactions between the genetic component and the environment. However, the universal epigenetic markers of osteoporosis are not yet defined. Finding the risk factors will predict the risk of osteoporosis at the preclinical stage, help define the course and severity of the disease, and develop preventive measures based on them to reduce the risk of fractures. Expanding knowledge in the field of bone biology, especially in the genetics of osteoporosis and osteoimmunology, showed that osteoporosis is a disease that occurs not only due to hormonal or mechanical disorders, but also as a clinically and genetically heterogeneous disease, and there are still unknown pathogenetic links in its structure. Decreases in bone mass and matrix mineralization as well as changes in bone microarchitecture can have different pathogenetic patterns of development and, moreover, there are unknown links of the pathogenesis of osteoporosis. It is possible that DNA methylation is one of these links and a mechanism for epigenetic regulation of gene expression. Evidence exists that this mechanism alongside regulatory miRNAs and post-translational modifications makes a significant contribution to the central processes of bone remodeling; however, the results of various studies vary greatly, and, therefore, there is a need to understand the significance of the accumulated data and to make them consistent. The purpose of this review is to compile and systematize data on the role of DNA methylation in bone metabolism in normal and pathological conditions, in the formation of osteoporosis, and to assess achievements and trends in this field of research and technologies for studying DNA methylation.

Gestational Vitamin D Supplementation Leads to Reduced Perinatal RXRA DNA Methylation: Results From the MAVIDOS Trial

We have previously demonstrated inverse associations between maternal 25(OH)-vitamin D status and perinatal DNA methylation at the retinoid-X-receptor-alpha (RXRA) locus and between RXRA methylation and offspring bone mass. In this study, we used an existing randomized trial to test the hypothesis that maternal gestational vitamin D supplementation would lead to reduced perinatal RXRA locus DNA methylation. The Maternal Vitamin D Osteoporosis Study (MAVIDOS) was a multicenter, double-blind, randomized, placebo-controlled trial of 1000 IU/day cholecalciferol or matched placebo from 14 weeks' gestation until delivery. Umbilical cord (fetal) tissue was collected at birth and frozen at -80°C (n = 453). Pyrosequencing was used to undertake DNA methylation analysis at 10 CpG sites within the RXRA locus (identified previously). T tests were used to assess differences between treatment groups in methylation at the three most representative CpG sites. Overall, methylation levels were significantly lower in the umbilical cord from offspring of cholecalciferol-supplemented mothers, reaching statistical significance at four CpG sites, represented by CpG5: mean difference in % methylation between the supplemented and placebo groups was -1.98% (95% CI, -3.65 to -0.32, p = 0.02). ENCODE (Encyclopedia of DNA Elements) evidence supports the functionality of this locus with strong DNase hypersensitivity and enhancer chromatin within biologically relevant cell types including osteoblasts. Enrichment of the enhancer-related H3K4me1 histone mark is also seen in this region, as are binding sites for a range of transcription factors with roles in cell proliferation, response to stress, and growth factors. Our findings are consistent with previous observational results and provide new evidence that maternal gestational supplementation with cholecalciferol leads to altered perinatal epigenetic marking, informing mechanistic understanding of early life mechanisms related to maternal vitamin D status, epigenetic marks, and bone development. © 2018 The Authors. Journal of Bone and Mineral Research Published by Wiley Periodicals Inc.

Bone-targeting drug delivery system of biomineral-binding liposomes loaded with icariin enhances the treatment for osteoporosis

Background

Osteoporosis is a bone-incapacitating malady and it is characterized by obvious bone mass loss and bone microarchitecture deterioration. Current treatments for osteoporosis have many limitations, including the non-obvious therapeutic effect and long-term safety issues. Icariin is a pharmacologically active flavonoid glycoside, which shows potential application in treatment of osteoporosis. But its clinical application is limited by the inherent disadvantages such as poor water solubility, first pass effect after oral administration, and low bioavailability. Moreover, due to lack of targeting ability, icariin cannot accumulate at the local diseased region to provide early protection from fractures. To solve the application problems of icariin and enhance its therapeutic effects on osteoporosis, this work aimed to design a targeting drug delivery system of biomineral-binding liposomes (BBL) mediated by pyrophosphate ions.

Results

Biomineral-binding liposomes enhanced the binding ability of liposomes with hydroxyapatite particles. It increased the serum level of alkaline phosphatase and reduced that of tartrate-resistant acid phosphatase 5b. Meanwhile, BBL increased the mechanical strength of femoral midshaft, preserving the trabecular bone microarchitecture. Moreover, BBL could initiate bone turnover/remodeling of rats with osteoporosis.

Conclusions

This drug targeting delivery system of BBL loading with icariin showed more therapeutic advantages than the free icariin for the treatment of osteoporosis, which may be a kind of valid candidate in future osteoporosis therapy.

Electronic supplementary material

The online version of this article (10.1186/s12951-019-0447-5) contains supplementary material, which is available to authorized users.

Structured diet and exercise guidance in pregnancy to improve health in women and their offspring: study protocol for the Be Healthy in Pregnancy (BHIP) randomized controlled trial

BACKGROUND

Evidence from epidemiological and animal studies support the concept of programming fetal, neonatal, and adult health in response to in utero exposures such as maternal obesity and lifestyle variables. Excess gestational weight gain (GWG), maternal physical activity, and sub-optimal and excess nutrition during pregnancy may program the offspring's risk of obesity. Maternal intake of dairy foods rich in high-quality proteins, calcium, and vitamin D may influence later bone health status. Current clinical practice guidelines for managing GWG are not founded on randomized trials and lack specific "active intervention ingredients." The Be Healthy in Pregnancy (BHIP) study is a randomized controlled trial (RCT) designed to test the effectiveness of a novel structured and monitored Nutrition + Exercise intervention in pregnant women of all pre-pregnancy weight categories (except extreme obesity), delivered through prenatal care in community settings (rather than in hospital settings), on the likelihood of women achieving recommended GWG and a benefit to bone status of offspring and mother at birth and six months postpartum.

METHODS

The BHIP study is a two-site RCT that will recruit up to 242 participants aged > 18 years at 12-17 weeks of gestation. After baseline measures, participants are randomized to either a structured and monitored Nutrition + Exercise (intervention) or usual care (control) program for the duration of their pregnancy. The primary outcome of the study is the percent of women who achieve GWG within the Institute of Medicine (IOM) guidelines. The secondary outcomes include: (1) maternal bone status via blood bone biomarkers during pregnancy; (2) infant bone status in cord blood; (3) mother and infant bone status measured by dual-energy absorptiometry scanning (DXA scan) at six months postpartum; (4) other measures including maternal blood pressure, blood glucose and lipid profiles, % body fat, and postpartum weight retention; and (5) infant weight z-scores and fat mass at six months of age.

DISCUSSION

If effective, this RCT will generate high-quality evidence to refine the nutrition guidelines during pregnancy to improve the likelihood of women achieving recommended GWG. It will also demonstrate the importance of early nutrition on bone health in the offspring.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT01689961 Registered on 21 September 2012.

High-throughput metabolomics investigates anti-osteoporosis activity of oleanolic acid via regulating metabolic networks using ultra-performance liquid chromatography coupled with mass spectrometry

BACKGROUND

Osteoporosis has brought about heavy socio-economic burden in the morbidity and medical expenses associated with osteoporosis treatment and various restrictions on behavior of their social roles. Oleanolic acid (OA) is an anti-osteoporosis natural product, but molecular mechanisms of therapeutic effect are not still well known.

PURPOSE

In this study, we explore anti-osteoporosis activity of oleanolic acid and predict the underlying mechanisms by metabolomics strategy.

METHODS

SD rats were intraperitoneal injection with prednison for once to establish osteoporosis model. Using metabolomics strategy based on ultra-performance liquid chromatography coupled with quadrupole time-of-flight/ mass spectrometry (UPLC-TOF/MS), serum samples of 24 rats were analyzed to seek differential metabolites and pathway associated with OA treatment of osteoporosis. In addition, the effect of OA on osteoporosis rats was also evaluated by clinical biochemistry indicators and bone density analysis.

RESULTS

Clinical biochemistry indicators and bone density of lumbar and femur were reversed by OA treatment. A total of 25 potential biomarkers were identified in the rats model of glucocorticoid-induced osteoporosis, and oleanolic acid have a regulatory effect on 17 of them that related to some vital metabolic pathway such as linoleic acid metabolism, valine, leucine and isoleucine biosynthesis, phenylalanine, tyrosine and tryptophan biosynthesis as well as cysteine and methionine metabolism. The ingenuity pathway analysis (IPA) platform is applied to further understanding the relationship between metabolic changes and therapeutic effect of OA, which the disordered state carbohydrate metabolism, molecular transport and lipid metabolism in glucocorticoid-induced osteoporosis rats are mainly ameliorated by oleanolic acid.

CONCLUSION

Metabolomics provides a novel method to investigate the anti-osteoporosis effects of OA and probe into the potential mechanisms, and will contributes to the development of new drugs.

Assessing bone mineral changes in response to vitamin D supplementation using natural variability in stable isotopes of Calcium in Urine

Osteoporosis is a chronic disease of public health importance, particularly in low and middle income countries. Measuring the bone mineral balance (BMB) in a non-invasive manner, and its response to different interventions, is critical to the definition of optimal strategies for its prevention and management. In this study, we demonstrate the usefulness of natural variability in calcium isotopes (δ^44/40Ca) of urine and the derived BMB estimates as a biomarker of bone health and its responsiveness to interventions. Vitamin D₃ is commonly used as a supplement for the prevention and treatment of osteoporosis, along with calcium supplements. We studied the effect of a short term vitamin D₃ supplementation on changes in urine δ^44/40Ca and the derived BMB. δ^44/40Ca before and after the vitamin D₃ supplementation yielded a statistically significant change (p = 0.050) with a positive δ^44/40Ca enrichment. The mean derived BMB was net positive (0.04 ± 0.05) in comparison to a net negative value for the control group (−0.03 ± 0.01). These results indicate the potential usefulness of urinary natural δ^44/40Ca and the derived BMB, which, along with bone mineral density could be used as a sensitive marker for precision in the prevention and treatment of osteoporosis.

Body Mass Index Trajectories From Birth to Midlife and Vertebral Dimensions in Midlife: the Northern Finland Birth Cohort 1966 Study

Vertebral fracture risk is higher among individuals with small vertebral dimensions. Obesity is a global health problem and may also contribute to bone size and fracture risk. In this work we report the association between life course body mass index (BMI) and vertebral cross-sectional area (CSA) in midlife. The Northern Finland Birth Cohort 1966 study with its 46-year follow-up provided the material for this study. A subsample of 780 individuals had attended lumbar magnetic resonance imaging (MRI) at the age of 46 years, and had records of objectively measured BMI from the ages of 0, 7, 15, 31, and 46 years. Of these, MRI-derived data on vertebral size was available for 682 individuals. We identified latent lifelong BMI trajectories by performing latent class growth modeling (LCGM) on the BMI data, and then used sex-stratified linear regression models to compare the identified trajectory groups in terms of midlife vertebral CSA. Gestational age, education years, adult height, lifelong physical activity, lifelong smoking history, and adulthood diet were assessed as potential confounders. Three distinct trajectory groups ("stable slim," "stable average," and "early onset overweight") were identified among both sexes. Comparisons to the stable slim trajectory revealed that vertebral CSA was significantly (p < 0.001) larger among the stable average and early onset overweight trajectories (69.8 and 118.6 mm² larger among men, 57.7 and 106.1 mm² larger among women, respectively). We conclude that lifelong BMI has a positive association with midlife vertebral size among both sexes. Future studies should characterize the mediating factors of this association.

Maternal vitamin D supplementation during pregnancy

Introduction

Maternal vitamin D status in pregnancy has been linked to many health outcomes in mother and offspring. A wealth of observational studies have reported on both obstetric outcomes and complications, including pre-eclampsia, gestational diabetes, mode and timing of delivery. Many foetal and childhood outcomes are also linked to vitamin D status, including measures of foetal size, body composition and skeletal mineralization, in addition to later childhood outcomes, such as asthma.

Sources of data

Synthesis of systematic and narrative reviews.

Areas of agreement and controversy

The findings are generally inconsistent in most areas, and, at present, there is a lack of data from high-quality intervention studies to confirm a causal role for vitamin D in these outcomes. In most areas, the evidence tends towards maternal vitamin D being of overall benefit, but often does not reach statistical significance in meta-analyses.

Growing points and areas timely for developing research

The most conclusive evidence is in the role of maternal vitamin D supplementation in the prevention of neonatal hypocalcaemia; as a consequence the UK department of health recommends that pregnant women take 400 IU vitamin D daily. High-quality randomized placebo-controlled trials, such as the UK-based MAVIDOS trial, will inform the potential efficacy and safety of vitamin D supplementation in pregnancy across a variety of outcomes.

The impact of musculoskeletal diseases on the presence of locomotive syndrome

OBJECTIVES

We assessed the impact of musculoskeletal diseases, depressive mental state, and hypertension on locomotive syndrome, a condition of reduced mobility requiring nursing care. Since locomotive syndrome is a major public health issue that needs attention, its relationship with functional inconvenience in performing daily activities was also investigated.

METHODS

We conducted a cross-sectional study using an Internet panel survey, comprising 747 persons aged 30-90 years. Demographics, personal medical history, and daily activity data were assessed. The 25-question Geriatric Locomotive Function Scale was used to diagnose locomotive syndrome. Stepwise linear regression analysis and logistic regression analysis were conducted to evaluate the association between locomotive syndrome, musculoskeletal diseases, and functional inconvenience.

RESULTS

Aging, osteoporosis, and low back pain significantly increased the risk of locomotive syndrome, followed by knee osteoarthritis and lumbar spinal stenosis. Locomotive syndrome was significantly related to depressive mental state and hypertension, and led to functional inconvenience in Seiza sitting, cleaning, shopping, and strolling.

CONCLUSION

Locomotive syndrome was associated with functional inconvenience in performing common daily activities involving the lower extremities and spine. Osteoporosis and aging were significantly associated with locomotive syndrome. The risk of locomotive syndrome may be decreased by treating comorbid osteoporosis and instituting exercise and diet-related modifications.

Metabolomic signatures of low birthweight: Pathways to insulin resistance and oxidative stress

Several studies suggest that low birthweight resulting from restricted intrauterine growth can leave a metabolic footprint which may persist into adulthood. To investigate this, we performed metabolomic profiling on 5036 female twins, aged 18-80, with weight at birth information available from the TwinsUK cohort and performed independent replication in two additional cohorts. Out of 422 compounds tested, 25 metabolites associated with birthweight in these twins, replicated in 1951 men and women from the Hertfordshire Cohort Study (HCS, aged 66) and in 2391 men and women from the North Finland Birth 1986 cohort (NFBC, aged 16). We found distinct heterogeneity between sexes and, after adjusting for multiple tests and heterogeneity, two metabolites were reproducible overall (propionylcarnitine and 3-4-hydroxyphenyllactate). Testing women only, we found other metabolites associated with lower birthweight from the meta-analysis of the three cohorts (2-hydroxy-butyric acid and γ-glutamylleucine). Higher levels of all these metabolites can be linked to insulin resistance, oxidative stress or a dysfunction of energy metabolism, suggesting that low birthweight in both twins and singletons are having an impact on these pathways in adulthood.

Lutein Enhances Bone Mass by Stimulating Bone Formation and Suppressing Bone Resorption in Growing Mice

Lutein is a member of the xanthophyll family of carotenoids, which are known to prevent hypoxia-induced cell damage in the eye by removing free radicals. However, its role in other tissues is controversial, and the effects of lutein on bone tissues are unknown. To identify a possible role of lutein in bone tissues, we examined the effects of lutein on bone formation and bone resorption and on femoral bone mass in mice. Lutein enhanced the formation of mineralized bone nodules in cultures of osteoblasts. On the other hand, lutein clearly suppressed 1α, 25-dihydroxyvitamin D₃-induced bone resorption as measured by pit formation in organ culture of mouse calvaria. In co-cultures of bone marrow cells and osteoblasts, lutein suppressed 1α, 25-dihydroxyvitamin D₃-induced osteoclast formation. In cultures of bone marrow macrophages, lutein suppressed soluble RANKL, the receptor activator of nuclear factor-kappaB (NF-κB) ligand, induced osteoclast formation. When five-week-old male mice were orally administered lutein for 4 weeks, the femoral bone mass was clearly enhanced in cortical bone, as measured by bone mineral density in dual X-ray absorptiometry and micro computed tomography (µCT) analyses. The present study indicates that lutein enhances bone mass in growing mice by suppressing bone resorption and stimulating bone formation. Lutein may be a natural agent that promotes bone turnover and may be beneficial for bone health in humans.

Weight Trajectories from Birth and Bone Mineralization at 7 Years of Age

OBJECTIVE

To assess whether different trajectories of weight gain since birth influence bone mineral content (BMC) and areal bone mineral density (aBMD) at 7 years of age.

STUDY DESIGN

We studied a subsample of 1889 children from the Generation XXI birth cohort who underwent whole-body dual-energy radiograph absorptiometry. Weight trajectories identified through normal mixture modeling for model-based clustering and labeled "normal weight gain," "weight gain during infancy," "weight gain during childhood," and "persistent weight gain" were used. Differences in subtotal BMC, aBMD, and size-corrected BMC (scBMC) at age 7 years according to weight trajectories were estimated through analysis of covariance.

RESULTS

Compared with the "normal weight gain" trajectory, children in the remaining trajectories had significantly greater BMC, aBMD, and scBMC at age 7 years, with the strongest associations for "persistent weight gain" (girls [BMC: 674.0 vs 559.8 g, aBMD: 0.677 vs 0.588 g/cm², scBMC: 640.7 vs 577.4 g], boys [BMC: 689.4 vs 580.8 g, aBMD: 0.682 vs 0.611 g/cm², scBMC: 633.0 vs 595.6 g]). After adjustment for current weight, and alternatively for fat and lean mass, children with a "weight gain during childhood" trajectory had greater BMC and aBMD than those with a "normal weight gain" trajectory, although significant differences were restricted to girls (BMC: 601.4 vs 589.2 g, aBMD: 0.618 vs 0.609 g/cm²).

CONCLUSION

Overall, children following a trajectory of persistent weight gain since birth had clearly increased bone mass at 7 years, but weight gain seemed slightly more beneficial when it occurred later rather than on a normal trajectory during the first 7 years of life.