Bone Mineral Quality Research Articles

CASE STUDY: IMPROVE BONE QUALITY AND SKELETAL MUSCLE MASS WITH A PROPER DIET AND EXERCISE FOR A PERSON AGED >60 YEARS OLD

Objective: To evaluate the effects of proper dietary and exercise practice on bone mineral quality, skelet muscle and fatty mass in a person aged > 60y. Subject & Methods: A 60 ys- old male subject, risk of osteoporosis received the daily diet 2000Kcal, Ca 1300mg, protein 1.7mg/kg.bw, vitamin D 665IU. Endurance exercise 3 times/week x 60 minutes/ session with moderate & high intensity levels; 45 minutes daily morning with moderate and light intensity, and 8 hours working at office. Heel- bone mineral density (BMD) measured by Quantitative Ultra-Sonic (QUS) instrument, skelets muscle and fat mass by Inbody 370S intrument every 6 months. The study period lasted 60 months (T60). Results: The T-score of heel bone increase from -2.4 (high risk osteoporosis) at the beginning (T0) to level of pick bone mass at T36, then maintained until T60 of intervention. The BUA (Broadband Ultrasound Attenuation), reflects the quality of the bone s’ trabecular, were also improved from 39.5dB/MHz to 108.1dB/MHz (+173.7%) from T0 to T60 respectively. The body weight, skelet-muscle & fat mass were maintained quite stable during 60 months of the study. Conclusion: A proper diet and exercise restored bone quality to pick bone mass levels, maintain skeletal muscle and body fat mass in the elderly.

Optimal dual calcium and cholecalciderol dosages for osteoporotic fracture risk patients

Background: Vitamin D is crucial for musculoskeletal health, promoting calcium absorption, osteoid tissue mineralization, and muscle function. Insufficient levels can lead to bone dystrophy, muscle weakness, and osteoporotic fractures. Aims: This research investigates the correlation between bone mineral density and osteoporotic fracture risk, including positive and negative influences, and aims to determine the optimal vitamin D level. Methods: This retrospective observational study examined 206 Jordanian rehabilitation and rheumatology clinic patients from September to November 2021. The participants were post-menopausal women and men over 60. The Age-adjusted Charlson Co-Morbidity Index and Functionality Grade system was used to assess participants' co-morbidity burden and functionality. DEXA scans assessed participants' proximal femoral hip and anteroposterior spine. Participants were divided into two Vit D groups: those below 30 ng/ml and those above 30. Results were compared using a Chi Square test. The study examined correlations, total variations, and Vit D prediction quality using logistic regression analyses. SPSS 23.0 was used for statistical analysis with a 5% significance level. Results: A binary logistic regression model was employed to simulate the correlation between the vitamin D levels of patients and their bone mineral density. The model indicated a 61.39% likelihood of having a fH_BMD (femoral head bone mineral density) equal to or greater than 0.755 g/cm2 when the vitamin D level is at its optimal value of 27.25 ng/ml. The model indicated a 27.25% likelihood of a fHOPF risk-free tool with a value of ≥3% when the optimal vitamin D level is 27.25 ng/ml. The model indicated a 17.74% likelihood of experiencing a significant osteoporotic fracture within the next 10 years. Conclusion: The findings of our study demonstrated a direct correlation between elevated levels of vitamin D and improved bone mineral quality indices that were examined. The serum 25-OH Cholecalciferol levels are more likely to have a beneficial effect on bone health status.

Assessment of Changes in Body Composition After 3 Months of Dulaglutide Treatment.

Changes in body composition accompanied by glucagon-like peptide 1 receptor agonist (GLP-1RA) induced weight loss have drawn much attention. However, fewer studies have reported body composition changes in patients receiving dulaglutide therapy in Chinese population. A total of 70 overweight/obese type 2 diabetes mellitus (T2DM) patients who received dulaglutide therapy were included. Clinical data were collected. Visceral fat area (VFA) and body composition were also measured. Changes in clinical indicators and body composition of patients before and after intervention were also analyzed. Correlation analysis and multiple linear regression model were used to evaluate the association between hemoglobin A1C (HbA1c) and body composition. The results showed that body weight (BW), VFA, body fat (BF), lean body mass (LBM), skeletal muscle mass (SMM) and water content were reduced after 3 months dulaglutide intervention. The lean body mass percentage (LBMP) and skeletal muscle mass percentage (SMMP) significantly increased. Moreover, there was no significant difference in bone mineral quality (BMQ) after the intervention. The multiple linear regression model revealed that the % change in BF was independently associated with % change in HbA1c (β = 0.449, t = 3.148, p=0.002). These results indicate that dulaglutide intervention does not cause muscle and bone mass loss while inducing weight loss, and % change in BF was independently associated with improved glucose control during dulaglutide therapy. This study offers some positive results to support the clinical application of dulaglutide.

P1163 Incidence and risk of hip replacement rate in patients with inflammatory bowel disease in Taiwan

Abstract Background The incidence and prevalence of inflammatory bowel disease (IBD) are low but increasing in Taiwan. Management of comorbidities such as osteoporosis is becoming increasingly important in treating patients with IBD. Hip fracture is the most serious consequence of low bone mineral quality and is associated with excess risk of mortality. The present study aimed to investigate the total/partial hip replacement in IBD patients in Taiwan. Methods In a matched nationwide cohort study, we evaluated the risk of total/partial hip replacement in IBD patients. We conducted univariable and multivariable Cox models to estimate the hazard ratios (HRs) and 95% confidence intervals (CIs). The Kaplan-Meier curves were plotted to describe the cumulative incidence of hip replacement among the two cohorts. Results a total of 51,301 patients with IBD and 153,903 patients without IBD were included in this study. In Table 1, distribution of gender, age, comorbidities, and medications were similar between two cohorts (SMD<0.1), except stroke, renal insufficiency, steroid, 5-ASA and anti-osteoporotic agents. The mean (standard deviation) age was 51.00 (17.76) and 49.89 (16.85) years and the sex ratio between female and male was approximately 50% and 50% in two cohorts, respectively. As shown in Table 2, patients with IBD had a significantly higher risk of hip replacement than the control group (adjusted HR=1.11, 95% CI=1.03-1.19). For the sake of a visual picture of cumulative incidence of hip replacement, consider the graphic representation in Figure 1 (Kaplan-Meier plot). Compared to female individuals, male individuals had significantly lower risks of hip replacement (adjusted HR=0.73, 95%CI=0.68-0.78). Older patients had more risk of hip replacement. Individuals aged 40-59, aged 60-79, aged >79 had significantly higher risks of hip replacement (adjusted HR >1, p-value<0.05) compared to individuals aged 20-39. Table 3 showed that IBD patients who are females, aged 40-59, or steroid users tended to have a higher risk of hip replacement compared to individuals without IBD (adjusted HR > 1, p-value < 0.05). We further stratified different dose of steroid use in IBD and non-IBD cohorts in Table 4. IBD patients receiving different steroid doses did not show influence on the risk of hip replacement. We demonstrated no difference in the hospital days, mortalities and morbidities among patients with hip replacement in non-IBD and IBD cohorts in Table 5. Higher rate of GI bleeding in IBD group had a significant difference than non-IBD group.; Conclusion Our present results indicate that patients with IBD had an overall higher total/partial hip replacement in Taiwan.

Non-Obese MKR Mouse Model of Type 2 Diabetes Reveals Skeletal Alterations in Mineralization and Material Properties.

ABSTRACTObesity is a common comorbidity of type 2 diabetes (T2D). Therefore, increased risk of fragility fractures in T2D is often confounded by the effects of obesity. This study was conducted to elucidate the mechanistic basis by which T2D alone leads to skeletal fragility. We hypothesized that obesity independent T2D would deteriorate bone's material quality by accumulating defects in the mineral matrix and undesired modifications in its organic matrix associated with increased oxidative stress and hyperglycemia. To test this hypothesis, we used 15‐week‐old male non‐obese mice with engineered muscle creatine kinase promoter/human dominant negative insulin growth factor 1 (IGF‐I) receptor (MKR) and FVB/N wild‐type (WT) controls (n = 12/group). MKR mice exhibit reduced insulin production and loss of glycemic control leading to diabetic hyperglycemia, verified by fasting blood glucose measurements (>250 mg/dL), without an increase in body weight. MKR mice showed a significant decrease in femoral radial geometry (cortical area, moment of inertia, cortical thickness, endosteal diameter, and periosteal diameter). Bone mineral density (BMD), as assessed by micro–computed tomography (μCT), remained unchanged; however, the quality of bone mineral was altered. In contrast to controls, MKR mice had significantly increased hydroxyapatite crystal thickness, measured by small‐angle X‐ray scattering, and elongated c‐axis length of the crystals evaluated by confocal Raman spectroscopy. There was an increase in changes in the organic matrix of MKR mice, associated with enhanced glycoxidation (carboxymethyl‐lysine [CML] and pentosidine) and overall glycation (fluorescent advanced glycation end products), both of which were associated with various measures of bone fragility. Moreover, increased CML formation positively correlated with elongated mineral crystal length, supporting the role of this negatively charged side chain to attract calcium ions, promote growth of hydroxyapatite, and build a physical link between mineral and collagen. Collectively, our results show, for the first time, changes in bone matrix in a non‐obese T2D model in which skeletal fragility is attributable to alterations in the mineral quality and undesired organic matrix modifications. © 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Уровень 25(ОН)D, 10-летняя вероятность основных остеопоротических переломов, минеральная плотность и качество костной ткани, жировая и обезжиренная масса у женщин в период пре- и постменопаузы

Актуальність. Постменопаузальний остеопороз викликає особливе занепокоєння, оскільки призводить до підвищеного ризику переломів з подальшим негативним впливом на здоров’я жінок літ­нього віку. Діагноз остеопорозу може бути встановлений за наявності низькоенергетичних переломів, що виникають без суттєвої травми, або на підставі низької мінеральної щільності кісткової тканини, визначеної методом двохенергетичної рентгенівської денситометрії. Мета дослідження: вивчити рівень 25(ОН)D, 10-річний ризик основних остеопоротичних переломів, мінеральну щільність та якість кісткової тканини, жирову та знежирену масу та визначити зв’язок між ними в жінок у період пре- та постменопаузи. Матеріали та методи. Обстежені 302 жінки віком 45–80 років (середній вік — 61,3 ± 7,7 року), які в подальшому відповідно до тривалості періоду пре- та постменопаузи були розподілені на 6 підгруп: І — пременопаузні жінки (n = 36; середній вік — 50,1 ± 3,4 року); II–VI — постменопаузні жінки (n = 266; середній вік — 62,8 ± 6,8 року). Всім обстеженим виконували дослідження мінеральної щільності кісткової тканини (МЩКТ) методом двофотонної рентгенівської денситометрії (ДРА) на двохенергетичному рентгенівському денситометрі Prodigy, GE Medical systems, model 8743, 2005, за стандартним протоколом. Оцінювали МЩКТ та Т-критерій поперекового відділу хребта, шийки стегнової кістки та всього скелета. Показник TBS поперекового відділу хребта визначали за допомогою методики TBS iNsight (Med-Imaps, Pessac, Франція). Рівень загального 25(ОН)D у сироватці крові визначали за допомогою електрохемілюмінесцентного методу на аналізаторі Еlecsus 2010 Roche Diagnostics (Німеччина), тест-системами Cobas. Десятирічну ймовірність основних остеопоротичних переломів і переломів стегнової кістки визначали з використанням української моделі FRAX без показників ДРА. Показники загальної жирової та знежиреної маси оцінювали з використанням ДРА. Результати. Виявлено вірогідний вплив тривалості періоду пре- та постменопаузи на варіабельність показників якості та щільності кісткової тканини (TBS (F = 6,85; p < 0,001), МЩКТ поперекового відділу хребта (F = 5,53; p < 0,001), МЩКТ шийки стегнової кістки (F = 10,25; p < 0,001), МЩКТ всього скелета (F = 12,28; p < 0,001)). Серед 266 обстежених жінок у періоді постменопаузи на рівні поперекового відділу хребта остеопороз виявлено в 90 (33,8 %) осіб, остеопенію — у 108 (40,6 %), норму — у 68 (25,6 %); на рівні шийки стегнової кістки остеопороз виявлено в 47 (17,7 %) осіб, остеопенію — в 187 (70,3 %), норму — в 32 (12,0 %). 10-річний ризик ймовірності основних остеопоротичних переломів порівняно з пременопаузою вірогідно збільшувався в наступні періоди постменопаузи: 5–9 років — 3,58 ± 1,97 та 6,72 ± 3,23, p < 0,0001; 10–14 років — 3,58 ± 1,97 та 6,90 ± 2,78, p < 0,0001; 15–19 років — 3,58 ± 1,97 та 7,19 ± 3,23, p < 0,0001; 20–24 роки — 3,58 ± 1,97 та 8,03 ± 2,45, p < 0,0001. Дефіцит вітаміну D виявлено в 39,7 % (n = 120), недостатність — в 30,4 % (n = 92), норму — в 29,9 % (n = 90). Нами не виявлено вірогідного впливу сезонності та місяця обстеження на показники 25(ОН)D (F = 0,51; p = 0,89). Рівень 25(OH)D мав негативну кореляцію з показниками маси, ІМТ і жирової маси та позитивну кореляцію з 10-річною ймовірністю основних остеопоротичних переломів. Висновки. Встановлено вірогідний негативний вплив тривалості пре- та постменопаузи на варіабельність показників якості та мінеральної щільності кісткової тканини та позитивний вплив на варіабельність показників 10-річної ймовірності основних остеопоротичних переломів і переломів стегнової кістки. У жінок у постменопаузі ожиріння вважається захисним фактором для втрати кісткової маси й розвитку остеопорозу. За результатами регресійного аналізу доведено вірогідний негативний зв’язок між масою тіла, індексом маси тіла, загальною жировою масою та рівнем 25(ОН)D у сироватці крові, що потребує адекватного підходу до терапії дефіциту вітаміну D в умовах ожиріння.

MO476EFFECT OF ESTROGEN DEFICIENCY ON THE STATE OF BONE AND MINERAL METABOLISM IN WOMEN WITH STAGE III-V CHRONIC KIDNEY DISEASE

Abstract Background and Aims Clinical studies in recent years have revealed a close relationship between hormonal disorders in women with CKD and the duration and quality of life, bone mineral and related disorders of the cardiovascular system. In individual studies, there is a tendency to improve the indicators of mineral and bone metabolism and the state of the cardiovascular system in hormonal or other drug-induced correction of hormonal dysfunctions in women. - Aims to study the effect of estrogen deficiency on bone and mineral metabolism in a population of women suffering from CKD stages III-V Method The study included 52 women who met the clinical criteria for the possible appointment of hormone therapy (both replacement and combined oral contraceptives) for the purpose of a detailed examination of the state of their cardiovascular system and bone-mineral metabolism in dynamics (with an interval of 10-12 months) in order to assess the degree of influence of estrogen-deficient conditions on the course of such common complications of CKD as cardiovascular diseases and pathology of the bone system. The age of the patients ranged from 26 to 61 years (mean age-50.65±9.17 years). The duration of CPN averaged 77.02 months.. The stages of CKD were determined according to the K/DOQI (2012) criteria, and the glomerular filtration rate was calculated using the CKD-EPI formula. The following parameters were evaluated: the concentration of sclerostin, osteoprotegerin, fibroblast growth factor 23 (FGF-23), parathyroid hormone, total calcium, phosphorus, alkaline phosphatase, creatinine, and urea. Follicle-stimulating hormone( FSH), luteinizing hormone(LH) and estradiol were determined by solid-phase chemiluminescent enzyme immunoassay (commercial sets of Alkor-Bio, St. Petersburg). Serum concentrations of sclerostin, sRANKL (soluble RANKL), and osteoprotegerin were determined by the enzyme-linked immunoassay using Biomedica gruppe test systems. Results The examined patients showed hormonal dysfunctions (82%), accompanied by changes in the content of sex hormones: the concentration of estradiol was below normal: 123.4±72.5 pmol/l and 150.0-450.0 pmol/l, respectively, in patients and in normal (p<0.01), which confirms the presence of estrogen deficiency in the examined patients . Concentrations of FSH and LH exceeded the norm in the group of patients as a whole: 91.6±46.1 IU/l and 3.0-8.0 IU/l FSH content in patients and normal; 51.8±32.1 IU/l and 3.0-10.0 IU/l LH in patients and normal. In the group of patients as a whole, an increase in the level of sclerostin to 28.5 ± 9.2 pmol/l was detected ( norm 12±33.45 pmol/l), an increase in the level of osteoprotegerin to 6.9±0.4 pmol/l (norm 2.7 pmol/l). Positive and negative correlations were found between the levels of morphogenetic proteins, sex hormones, and characteristic parameters of hormonal dysfunctions Conclusion Pre-and postmenopausal women with CKD have hormonal dysfunctions, including disorders of sexual and reproductive function, menstrual cycle, decreased fertility, increased risks of miscarriage at its onset, the basis of hormonal dysfunctions is the absence of LH peaks and changes in the concentration of estradiol depending on the phase of the cycle, hypoestrogenemia. It is assumed that there is a pathogenetic link between hormonal dysfunctions and disorders in the system of bone metabolism regulatory proteins in patients with CKD.

Body Composition and Bone Mineral Quality in Phenylketonuria: Influence of Pubertal Development

Background/Objectives: Early diagnosis and a low-Phe diet significantly improved prognosis of PKU patients whose management is now-a-day mostly focused on preventing nutritional imbalances and resulting comorbidities. Puberty is a turning point for the risk to develop overweight and bone quality impairment. The present study aims to evaluate body composition and bone quality in prepubertal and pubertal PKU patients. Subjects/Methods: This is an observational, prospective study on an historical cohort of patients with PKU aged between 4.1 and 18 years, with early diagnosis and continuous protein-restrictive diet treatment. Bioimpedance, weight measurements, height, body mass index calculation, and quantitative ultrasound were collected. Sexual maturity was evaluated by using the Tanner staging. Results: Thirty PKU patients (14 prepubertal, 16 pubertal) were included in the study. Mean BMI was within the normal range in both groups, although fat content was higher in prepubertal, whereas lean mass was higher in the pubertal group who had also a higher total protein content. Among QUS parameters, bone quality index and broadband ultrasound were lower in prepubertal children than in adolescents, with a Z-score BQI within the osteopenia range in both of them. Conclusions: Pubertal patients with PKU develop a higher lean mass and protein content. If on one hand the high non-Phe protein intake in the pubertal period may promote increase in bone mineral quality, on the other hand the higher protein retention, typical of this period, may increase the risk for hyperinsulinism and glucose intolerance in later life. Adjusting dietary management by modulating total protein intake in the peripubertal period could result in better management of PKU patients.

Imaging the osteochondral interface for potential early diagnosis of osteoarthritis with a nanoparticle-based contrast agent

Purpose: The osteochondral interface has been identified as a key structure in the development of osteoarthritis. As the disease develops, subchondral bone thickens and large perforations appear. Furthermore, the bone mineral quality is reduced and bone cysts appear, alongside a breakdown in cartilage matrix and proteoglycan loss. To investigate this phenomenon in the progression of OA we propose using preclinical investigations of small animal models with contrast enhanced micro-computed tomography (microCT) in a longitudinal manner.

Periconception maternal low-protein diet adversely affects male mouse fetal bone growth and mineral density quality in late gestation.

Adverse programming of adult non-communicable disease can be induced by poor maternal nutrition during pregnancy and the periconception period has been identified as a vulnerable period. In the current study, we used a mouse maternal low-protein diet fed either for the duration of pregnancy (LPD) or exclusively during the preimplantation period (Emb-LPD) with control nutrition provided thereafter and postnatally to investigate effects on fetal bone development and quality. This model has been shown previously to induce cardiometabolic and neurological disease phenotypes in offspring. Micro 3D computed tomography examination at fetal stages Embryonic day E14.5 and E17.4, reflecting early and late stages of bone formation, demonstrated LPD treatment caused increased bone formation of relative high mineral density quality in males, but not females, at E14.5, disproportionate to fetal growth, with bone quality maintained at E17.5. In contrast, Emb-LPD caused a late increase in male fetal bone growth, proportionate to fetal growth, at E17.5, affecting central and peripheral skeleton and of reduced mineral density quality relative to controls. These altered dynamics in bone growth coincide with increased placental efficiency indicating compensatory responses to dietary treatments. Overall, our data show fetal bone formation and mineral quality is dependent upon maternal nutritional protein content and is sex-specific. In particular, we find the duration and timing of poor maternal diet to be critical in the outcomes with periconceptional protein restriction leading to male offspring with increased bone growth but of poor mineral density, thereby susceptible to later disease risk.

Inflammatory Bowel Disease: A Nationwide Study of Hip Fracture and Mortality Risk After Hip Fracture

With rising rates of inflammatory bowel diseases [IBD] in older adults, management of comorbidities such as osteoporosis is becoming increasingly important. Hip fracture [HF] is the most serious consequence of low bone mineral quality and is associated with excess risk of mortality. For older IBD patients, there are only limited data available. Therefore, we aimed to assess the association of IBD with HF, and all-cause mortality risk after HF, among IBD patients older than 50 years. In a national database-registered case-control study, 56 821 HF cases aged ≥50 years, and 113 718 age-, sex- and region-matched non-hip-fracture controls, were analysed between 2012 and 2016. A history of IBD was assessed from data from Austrian social health insurance funds. Logistic regression and Cox proportional multivariate models were used to test the association of IBD with HF and post-hip fracture mortality risk. A total of 531 patients were identified with IBD (25.0% men, mean age 81.2 years, standard deviation [SD] 9.7). Analysis, adjusted for anti-osteoporotic treatment, use of glucocorticoids, and selected medications, showed that IBD patients had an increased odds of HF (odds ratio [[OR] 2.22, 95% confidence interval [CI] 1.86-2.64). Patients with Crohn's disease [CD] revealed a higher HF odds in contrast to patients with ulcerative colitis [OR 2.91, 95% CI 2.17-3.89 and OR 1.89, 95% CI 1.52-2.35, respectively]. Overall mortality risk after HF was higher among female CD patients [HR 1.75, 95% CI 1.28-2.41] than in the general population. IBD was strongly associated with HF in older patients. Post-hip fracture mortality risk was elevated particularly in women with CD.

The Implication of Spatial Statistics in Human Mesenchymal Stem Cell Response to Nanotubular Architectures.

IntroductionIn recent years there has been ample interest in nanoscale modifications of synthetic biomaterials to understand fundamental aspects of cell-surface interactions towards improved biological outcomes. In this study, we aimed at closing in on the effects of nanotubular TiO2 surfaces with variable nanotopography on the response on human mesenchymal stem cells (hMSCs). Although the influence of TiO2 nanotubes on the cellular response, and in particular on hMSC activity, has already been addressed in the past, previous studies overlooked critical morphological, structural and physical aspects that go beyond the simple nanotube diameter, such as spatial statistics.MethodsTo bridge this gap, we implemented an extensive characterization of nanotubular surfaces generated by anodization of titanium with a focus on spatial structural variables including eccentricity, nearest neighbour distance (NND) and Voronoi entropy, and associated them to the hMSC response. In addition, we assessed the biological potential of a two-tiered honeycomb nanoarchitecture, which allowed the detection of combinatory effects that this hierarchical structure has on stem cells with respect to conventional nanotubular designs. We have combined experimental techniques, ranging from Scanning Electron (SEM) and Atomic Force (AFM) microscopy to Raman spectroscopy, with computational simulations to characterize and model nanotubular surfaces. We evaluated the cell response at 6 hrs, 1 and 2 days by fluorescence microscopy, as well as bone mineral deposition by Raman spectroscopy, demonstrating substrate-induced differential biological cueing at both the short- and long-term.ResultsOur work demonstrates that the nanotube diameter is not sufficient to comprehensively characterize nanotubular surfaces and equally important parameters, such as eccentricity and wall thickness, ought to be included since they all contribute to the overall spatial disorder which, in turn, dictates the overall bioactive potential. We have also demonstrated that nanotubular surfaces affect the quality of bone mineral deposited by differentiated stem cells. Lastly, we closed in on the integrated effects exerted by the superimposition of two dissimilar nanotubular arrays in the honeycomb architecture.DiscussionThis work delineates a novel approach for the characterization of TiO2 nanotubes which supports the incorporation of critical spatial structural aspects that have been overlooked in previous research. This is a crucial aspect to interpret cellular behaviour on nanotubular substrates. Consequently, we anticipate that this strategy will contribute to the unification of studies focused on the use of such powerful nanostructured surfaces not only for biomedical applications but also in other technology fields, such as catalysis.

High risk of lumbar spine osteoporosis with the RANK rs3018362 polymorphism

Osteoporosis is characterized by reduced bone mineral density (BMD) and quality, increasing the risk of fractures. A large number of genes involved in bone metabolism have been implicated in the genesis of osteoporosis; these include RANK and RANKL. Polymorphisms of these genes have been implicated in osteoporosis. The aim of this study was to determine the association of the RANK rs3018362 and RANKL rs12585014 polymorphisms with risk of osteoporosis. Four hundred Mexican women aged 40 years old or above were genotyped by real-time PCR and several demographic and risk factors were explored. The GA and AA genotypes of the rs3018362 polymorphism were associated with a high risk of osteoporosis in the dominant model (p=.0062; OR = 2.16, 95% CI: 1.24–3.78). In summary, the rs3018362 polymorphism in the RANK gene seems to be associated with osteoporosis of the lumbar spine while the RANKL rs12585014 is not, although more studies are needed to confirm these results.

Bone quality assessment of osteogenic cell cultures by Raman microscopy.

The use of autologous stem/progenitor cells represents a promising approach to the repair of craniofacial bone defects. The calvarium is recognized as a viable source of stem/progenitor cells that can be transplanted in vitro to form bone. However, it is unclear if bone formed in cell culture is similar in quality to that found in native bone. In this study, the quality of bone mineral formed in osteogenic cell cultures were compared against calvarial bone from postnatal mice. Given the spectroscopic resemblance that exists between cell and collagen spectra, the feasibility of extracting information on cell activity and bone matrix quality were also examined. Stem/progenitor cells isolated from fetal mouse calvaria were cultured onto fused-quartz slides under osteogenic differentiation conditions for 28 days. At specific time intervals, slides were removed and analyzed by Raman microscopy and mineral staining techniques. We show that bone formed in culture at Day 28 resembled calvarial bone from 1-day-old postnatal mice with comparable mineralization, mineral crystallinity, and collagen crosslinks ratios. In contrast, bone formed at Day 28 contained a lower degree of ordered collagen fibrils compared with 1-day-old postnatal bone. Taken together, bone formed in osteogenic cell culture exhibited progressive matrix maturation and mineralization but could not fully replicate the high degree of collagen fibril order found in native bone.

Quantitative ultrasonometry for the diagnosis of osteoporosis in human skeletal remains: New methods and standards

Osteoporosis, a complex and heterogeneous disorder with a multi-factorial etiology, is characterized by abnormal bone loss leading to an increased risk of fractures.In recent years, the study of osteoporosis and bone mineral quality has received increasing interest by biological anthropologists. In particular, the study of bone quality in ancient populations in relation to sex, age and cultural background can provide important insights into the diachronic evolution of a seemingly modern pathology. However, a number of challenges remain in the determination of bone loss in ancient remains, partly due to the methodological approaches applied in the anthropological analysis. This underlines the need for a new methodology and new standards, specifically created and adapted to human skeletal remains.The current study aims to develop a new methodology to assess bone quality in modern and ancient human skeletal remains using Quantitative Ultrasonometry, applied for the first time to a skeletal sample of known age-at-death and sex (Frassetto collection, University of Bologna). After the assessment of intra- and inter-observer reliability, new ultrasonometric standards based on the analysis of age-related and sex-related changes in bone quantity and quality were created, providing a reference point for the analysis of osteoporosis and bone loss in skeletal remains. The applicability of the method was tested in a medieval sample including both males and females. The low intra- and inter-observer errors suggest that the Phalangeal Ultrasonometry is a reliable and valid technique that can be applied to modern and ancient human skeletons.

Impact of vitamin C on teriparatide treatment in the improvement of bone mineral density, strength, and quality in vitamin C-deficient rats.

Age-related decreases in serum levels of vitamin C (VC) may negatively affect the efficacy of anti-osteoporotic pharmacotherapy. The purpose of this study was to evaluate the effects of VC and teriparatide (TPTD) on bone mineral density (BMD), strength, and quality in VC-deficient osteogenic disorder Shionogi (ODS) rats. Six-month-old female ODS rats were divided into an untreated ODS control group, a VC group, a TPTD group, and a VC + TPTD group, based on the administration of VC and TPTD (n = 10 each). VC was given as 2.0mg/ml supplemented water. TPTD was administered subcutaneously once a week at 30µg/kg body weight. After 12weeks of treatment, BMDs of the femur and lumbar spine, bone strengths of the femoral diaphysis and metaphysis, and cancellous bone quality of proximal tibiae as estimated by Fourier transform infrared spectroscopy (FTIR) were compared between groups. Compared to the ODS control group, the VC group showed significantly higher total femoral BMD, but the TPTD group showed significantly higher femoral and lumbar spinal BMD, maximum load of femoral metaphysis, and hydroxyapatite (HA) crystallinity by FTIR (p < 0.05). In addition to the increases shown in the TPTD group, the VC + TPTD group also showed significantly higher stiffness of the femoral diaphysis and breaking energy of the femoral metaphysis compared to the ODS control group (p < 0.05). These results indicated that TPTD alone increased cancellous/cortical BMD and cancellous bone strength with improvement of HA crystallinity in ODS rats, but addition of VC supplementation further improved cortical bone strength.

Raman Spectroscopy detects changes in Bone Mineral Quality and Collagen Cross-linkage in Staphylococcus Infected Human Bone

Diagnosis of osteomyelitis presents a formidable challenge. Lack of pathognomonic clinical sign(s) and diagnostic tests that can diagnose osteomyelitis at an early stage contribute to this difficulty. If the diagnosis is not made early, the disease becomes very difficult to eradicate and can lead to limb threatening and potentially life-threatening complications. Staphylococcus aureus is the most common organism causing osteomyelitis. Raman Spectroscopy provides information about molecular vibration that could potentially be harnessed as a spectral signature for cellular changes in specific pathologic conditions. In this study we describe a technique using Raman spectroscopy that could potentially be used to diagnose staphylococcal osteomyelitis. Human bone samples were co-cultured with Staphylococcus aureus (S. aureus) and the effects of bacterial growth on bone quality were then monitored using Raman spectroscopy. A major drop in the bone mineral quality and crystallinity was observed in the infected bones compared to the controls. S. aureus infection was also found to alter the collagen cross-linking. Our study shows that specific spectral signatures are present for the cause as well as the effect of staphylococcal osteomyelitis, opening the possibility of developing a useful diagnostic modality for early and rapid diagnosis of this condition.

Bone matrix development in steroid-induced osteoporosis is associated with a consistently reduced fibrillar stiffness linked to altered bone mineral quality

Glucocorticoid-induced osteoporosis (GIOP) is a major secondary form of osteoporosis, with the fracture risk significantly elevated – at similar levels of bone mineral density – in patients taking glucocorticoids compared with non-users. The adverse bone structural changes at multiple hierarchical levels in GIOP, and their mechanistic consequences leading to reduced load-bearing capacity, are not clearly understood. Here we combine experimental X-ray nanoscale mechanical imaging with analytical modelling of the bone matrix mechanics to determine mechanisms causing bone material quality deterioration during development of GIOP. In situ synchrotron small-angle X-ray diffraction combined with tensile testing was used to measure nanoscale deformation mechanisms in a murine model of GIOP, due to a corticotrophin-releasing hormone promoter mutation, at multiple ages (8-, 12-, 24- and 36 weeks), complemented by quantitative micro-computed tomography and backscattered electron imaging to determine mineral concentrations. We develop a two-level hierarchical model of the bone matrix (mineralized fibril and lamella) to predict fibrillar mechanical response as a function of architectural parameters of the mineralized matrix. The fibrillar elastic modulus of GIOP-bone is lower than healthy bone throughout development, and nearly constant in time, in contrast to the progressively increasing stiffness in healthy bone. The lower mineral platelet aspect ratio value for GIOP compared to healthy bone in the multiscale model can explain the fibrillar deformation. Consistent with this result, independent measurement of mineral platelet lengths from wide-angle X-ray diffraction finds a shorter mineral platelet length in GIOP. Our results show how lowered mineralization combined with altered mineral nanostructure in GIOP leads to lowered mechanical competence. Significance StatementIncreased fragility in musculoskeletal disorders like osteoporosis are believed to arise due to alterations in bone structure at multiple length-scales from the organ down to the supramolecular-level, where collagen molecules and elongated mineral nanoparticles form stiff fibrils. However, the nature of these molecular-level alterations are not known. Here we used X-ray scattering to determine both how bone fibrils deform in secondary osteoporosis, as well as how the fibril orientation and mineral nanoparticle structure changes. We found that osteoporotic fibrils become less stiff both because the mineral nanoparticles became shorter and less efficient at transferring load from collagen, and because the fibrils are more randomly oriented. These results will help in the design of new composite musculoskeletal implants for bone repair.

The challenges of promoting osteogenesis in segmental bone defects and osteoporosis.

Conventional clinical management of complex bone healing scenarios continues to result in 5-10% of fractures forming non-unions. Additionally, the aging population and prevalence of osteoporosis-related fractures necessitate the further exploration of novel ways to augment osteogenesis in this special population. This review focuses on the current clinical modalities available, and the ongoing clinical and pre-clinical research to promote osteogenesis in segmental bone defects, delayed unions, and osteoporosis. In summary, animal models of fracture repair are often small animals as historically significant large animal models, like the dog, continue to gain favor as companion animals. Small rodents have well-documented limitations in comparing to fracture repair in humans, and few similarities exist. Study design, number of studies, and availability of funding continue to limit large animal studies. Osteoinduction with rhBMP-2 results in robust bone formation, although long-term quality is scrutinized due to poor bone mineral quality. PTH 1-34 is the only FDA approved osteo-anabolic treatment to prevent osteoporotic fractures. Limited to 2 years of clinical use, PTH 1-34 has further been plagued by dose-related ambiguities and inconsistent results when applied to pathologic fractures in systematic human clinical studies. There is limited animal data of PTH 1-34 applied locally to bone defects. Gene therapy continues to gain popularity among researchers to augment bone healing. Non-integrating viral vectors and targeted apoptosis of genetically modified therapeutic cells is an ongoing area of research. Finally, progenitor cell therapies and the content variation of patient-side treatments (e.g., PRP and BMAC) are being studied. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1559-1572, 2018.

Biomolecular regulation, composition and nanoarchitecture of bone mineral

Tough natural nanocomposites like bone, nacre and sea sponges contain within their hierarchy, a mineral (phosphate, silicate or carbonate) phase that interacts with an organic phase. In bone, the role of mineral ultrastructure (organization, morphology, composition) is crucial to the mechanical and biological properties of the tissue. Better understanding of mineral interaction with the organic matrix, in particular non-collagenous proteins, osteocalcin (OC) and osteopontin (OPN), can lead to better design of biomimetic materials. Using small angle x-ray scattering (SAXS) and wavelength dispersive spectroscopy (WDS) on single (OC−/− and OPN−/−) and double (OC-OPN−/−;−/−) genetic knockout mice bones, we demonstrate that both osteocalcin and osteopontin have specific roles in the biomolecular regulation of mineral in bone and together they are major determinants of the quality of bone mineral. Specifically, for the first time, we show that proteins osteocalcin and osteopontin regulate bone mineral crystal size and organization in a codependent manner, while they independently determine crystal shape. We found that OC is more dominant in the regulation of the physical properties of bone mineral, while OPN is more dominant in the regulation of the mineral composition.