Mechanical-Stress-Related Epigenetic Regulation of ZIC1 Transcription Factor in the Etiology of Postmenopausal Osteoporosis.

Mechanical loading exerts a profound influence on bone density and architecture, but the exact mechanism is unknown. Our study shows that expression of the neurological transcriptional factor zinc finger of the cerebellum 1 (ZIC1) is markedly increased in trabecular bone biopsies in the lumbar spine compared with the iliac crest, skeletal sites of high and low mechanical stress, respectively. Human trabecular bone transcriptome analyses revealed a strong association between ZIC1 mRNA levels and gene transcripts characteristically associated with osteoblasts, osteocytes and osteoclasts. This supposition is supported by higher ZIC1 expression in iliac bone biopsies from postmenopausal women with osteoporosis compared with age-matched control subjects, as well as strongly significant inverse correlation between ZIC1 mRNA levels and BMI-adjusted bone mineral density (BMD) (Z-score). ZIC1 promoter methylation was decreased in mechanically loaded vertebral bone compared to unloaded normal iliac bone, and its mRNA levels correlated inversely with ZIC1 promoter methylation, thus linking mechanical stress to epigenetic control of gene expression. The findings were corroborated in cultures of rat osteoblast progenitors and osteoblast-like cells. This study demonstrates for the first time how skeletal epigenetic changes that are affected by mechanical forces give rise to marked alteration in bone cell transcriptional activity and translate to human bone pathophysiology.

Assessing donor-to-donor variability in human intestinal organoid cultures.

Donor-to-donor variability in primary human organoid cultures has not been well characterized. As these cultures contain multiple cell types, there is greater concern that variability could lead to increased noise. In this work we investigated donor-to-donor variability in human gut adult stem cell (ASC) organoids. We examined intestinal developmental pathways during culture differentiation in ileum- and colon-derived cultures established from multiple donors, showing that differentiation patterns were consistent among cultures. This finding indicates that donor-to-donor variability in this system remains at a manageable level. Intestinal metabolic activity was evaluated by targeted analysis of central carbon metabolites and by analyzing hormone production patterns. Both experiments demonstrated similar metabolic functions among donors. Importantly, this activity reflected intestinal biology, indicating that these ASC organoid cultures are appropriate for studying metabolic processes. This work establishes a framework for generating high-confidence data using human primary cultures through thorough characterization of variability.

Intestinal MYC modulates obesity-related metabolic dysfunction.

MYC is a transcription factor with broad biological functions, notably in the control of cell proliferation. Here, we show that intestinal MYC regulates systemic metabolism. We find that MYC expression is increased in ileum biopsies from individuals with obesity and positively correlates with body mass index. Intestine-specific reduction of MYC in mice improves high-fat-diet-induced obesity, insulin resistance, hepatic steatosis and steatohepatitis. Mechanistically, reduced expression of MYC in the intestine promotes glucagon-like peptide-1 (GLP-1) production and secretion. Moreover, we identify Cers4, encoding ceramide synthase 4, catalysing de novo ceramide synthesis, as a MYC target gene. Finally, we show that administration of the MYC inhibitor 10058-F4 has beneficial effects on high-fat-diet-induced metabolic disorders, and is accompanied by increased GLP-1 and reduced ceramide levels in serum. This study positions intestinal MYC as a putative drug target against metabolic diseases, including non-alcoholic fatty liver disease and non-alcoholic steatohepatitis.

Graded Eimeria challenge linearly regulated growth performance, dynamic change of gastrointestinal permeability, apparent ileal digestibility, intestinal morphology, and tight junctions of broiler chickens.

This study was conducted to evaluate graded Eimeria challenge on growth performance, apparent ileal digestibility, gastrointestinal permeability, intestinal morphology, gene expression of tight junction protein, and intestinal lesion scores in broiler chickens. There were 5 groups in this study, including a control and 4 different Eimeria treatment doses. A mixed Eimeria spp. solution with 50,000 Eimeria maxima, 50,000 Eimeria tenella, and 250,000 Eimeria acervulina per milliliter was prepared for the high-dose challenge treatment. The 2-fold serial dilution was used to make the medium-high (25,000 E. maxima; 25,000 E. tenella; 125,000 E. acervulina), the medium-low (12,500 E. maxima; 12,500 E. tenella; 62,500 E. acervulina), and the low challenge dose (6,250 E. maxima; 6,250 E. tenella; 31,250 E. acervulina). A total of three hundred sixty 13-day-old male broiler chickens were randomly allocated into 5 treatments with 6 replicated cages. Growth performance was calculated from 0 to 6 D postinfection (DPI). Intestine lesion was scored on 6 DPI. Gastrointestinal permeability was measured on 3, 5, 6, 7, and 9 DPI. The results indicated significant linear reduction in growth performance, intestinal villi height, and ileal nutrient digestibility in response to the increase of Eimeria challenge dose. Furthermore, gene expression of tight junction protein was linearly upregulated by the increasing challenge doses. Significant linear increases of gastrointestinal permeability were found on 5, 6, and 7 DPI (P < 0.01). On 9 DPI, the gastrointestinal permeability was recovered back to normal level in the challenge groups. In conclusion, the higher Eimeria doses birds received, the more severe intestine damage was observed in several gastrointestinal health parameters. The medium-low or medium-high levels of mixed Eimeria oocysts is suggested as an optimum Eimeria-challenge dose to establish a subclinical challenge model for future studies evaluating nutritional strategies. Moreover, it is recommended to measure gastrointestinal permeability on 5 DPI with higher oocysts doses and 6 DPI when using the lower oocysts doses.

Jagged1 promotes mineralization in human bone-derived cells.

OBJECTIVES: The present study aimed to investigate the expression of Notch signaling components during osteogenic differentiation in vitro and bone healing in vivo. In addition, the influence of Notch signaling on osteogenic differentiation of human bone-derived cells was examined. METHODS: Gene expression profiling of osteogenic differentiation of human bone marrow-derived mesenchymal stromal cells in vitro (GSE80614) and bone healing period of murine tibial fracture in vivo (GSE99388) was downloaded from Gene Expression Omnibus database. The expression of Notch signaling components was obtained from bioinformatic tools. Human bone-derived cells were isolated from alveolar and iliac bone. Cells were seeded on Jagged1 immobilized surface. Osteogenic marker gene expression and mineralization were examined using real-time polymerase chain reaction and alizarin red s staining, respectively. RESULTS: From bioinformatic analysis of gene expression profiling, various Notch signaling components were differentially expressed during osteogenic differentiation of human bone marrow-derived mesenchymal stromal cells in vitro and bone healing period of murine tibial fracture in vivo. The common genes differentially regulated of these two datasets were Hes1, Aph1a, Nsctn, Furin, Adam17, Hey1, Pcsk5, Nedd4, Jag1, Heyl, Notch3, Dlk1, and Hey2. For an in vitro analysis, the mineral deposition markedly increased after seeding human bone-derived cells on Jagged1 immobilized surface, correspondingly with the increase of ALP mRNA expression. Jagged1 treatment downregulated TWIST2 mRNA expression in both human alveolar and iliac bone-derived cells. CONCLUSION: Notch signaling is regulated during osteogenic differentiation and bone healing. In addition, the activation of Notch signaling promotes osteogenic differentiation in human alveolar and iliac bone-derived cells. Therefore, Notch signaling manipulation could be a useful approach for enhancing bone regeneration.

Reduction of Cortical Bone Turnover and Erosion Depth After 2 and 3 Years of Denosumab: Iliac Bone Histomorphometry in the FREEDOM Trial.

Denosumab, a RANKL inhibitor, reduced the risk of vertebral, hip, and nonvertebral fractures in the Fracture REduction Evaluation of Denosumab in Osteoporosis every 6 Months (FREEDOM) trial of postmenopausal women with osteoporosis compared with placebo. Previous bone histomorphometric analysis in FREEDOM showed decreased bone resorption and turnover in cancellous bone after 2 and 3 years. The purpose of the present study was to evaluate the effects of denosumab compared with placebo in the cortical compartment from transiliac bone biopsies obtained during FREEDOM. A total of 112 specimens were evaluable for cortical histomorphometry, including 67 obtained at month 24 (37 placebo, 30 denosumab) and 45 at month 36 (25 placebo, 20 denosumab). Eroded surface, osteoclast surface, erosion depth, and wall thickness were measured on the endocortical surface. Cortical thickness and cortical porosity were also measured. Dynamic parameters of bone formation were assessed for endocortical, periosteal, and intracortical envelopes. Endocortical osteoclast surface, eroded surface, and mean and maximum erosion depth were significantly lower in the denosumab group versus placebo at months 24 and 36 (p < 0.0001 to p = 0.04). Endocortical wall thickness and intracortical measures (cortical porosity and cortical thickness) were not different between the two groups. Dynamic parameters were low with tetracycline labels in cortical bone observed in 13 (43%) and 10 (50%) of denosumab biopsies at months 24 and 36, respectively, reflecting a marked decrease in bone turnover. In conclusion, our data reveal the mechanism of action of denosumab on cortical bone: inhibition of osteoclastic resorption and reduced activation of new remodeling sites. In addition, reduced endocortical erosion depth with no change of wall thickness may contribute to increased bone strength by reducing the bone loss and fragility associated with deep resorption cavities and may likely contribute to the greater BMD gain with denosumab than with other antiresorptive agents. © 2018 The Authors. Journal of Bone and Mineral Research Published by Wiley Periodicals Inc.

Differential osteopontin expression in human osteoblasts derived from iliac crest and alveolar bone and its role in early stages of angiogenesis.

In our previous study, we revealed significant differences of osteopontin (OPN) gene expression in primary human osteoblasts (HOBs) derived from iliac crest bone (iHOBs) and alveolar bone (aHOBs). The present study aims at assigning this discriminative expression to a possible biologic function. OPN is known to be involved in several pathologic and physiologic processes, among others angiogenesis. Therefore, we studied the reaction of human umbilical vein endothelial cells (HUVECs) to HOB-derived OPN regarding angiogenesis. To this end, human primary explant cultures of both bone entities from ten donors were established. Subsequent transcription analysis detected higher gene expression of OPN in iHOBs compared to aHOBs, thereby confirming the results of our previous study. This difference was particularly apparent when cultures were derived from female donors. Hence, OPN protein expression as well as the angiogenic potential of OPN was analyzed, originating from HOBs of one female donor. In accordance to the gene expression level, secreted OPN was more abundant in the supernatant of iHOBs than in aHOBs. Moreover, secreted OPN was found to stimulate migration of HUVECs, but not proliferation or tube formation. These results indicate an involvement in very early stages of angiogenesis and a functional distinction of OPN from HOBs derived from different bone entities.

The unexpected presence of iron in bone biopsies of hemodialysis patients.

PURPOSE: Bone biopsy defines classical diseases that constitute the renal osteodystrophy. There is a recent concern regarding other histological findings that are not appreciated by using the turnover, mineralization, and volume (TMV) classification. Iron (Fe) overload has been considered a new challenge and the real significance of the presence of this metal in bones is not completely elucidated. Therefore, the main goal of the current study was to not only to identify bone Fe, but also correlate its presence with demographic, and biochemical characteristics. METHODS: This is a cross-sectional analysis of bone biopsies performed in 604 patients on dialysis from 2010 to 2014 in a tertiary academic Hospital. RESULTS: Histomorphometric findings revealed the presence of Fe in 29.1%. Fe was associated with higher levels of serum ferritin and serum calcium. No TMV status was related to Fe bone overload. CONCLUSION: Our study has highlighted that the presence of Fe in one-third of bone samples has unknown clinical significance. The lack of other contemporary bone biopsy study reporting Fe prevents us from comparison. The findings presented here should be specifically addressed in a future research and will require attention prior to implementation of any clinical guideline. If any proposed treatment, however, would change the bone Fe-related morbidity is undetermined.

HIF-1-mediated expression of Foxo1 serves an important role in the proliferation and apoptosis of osteoblasts derived from children's iliac cancellous bone.

Activation of the transcription factor hypoxia inducible factor­1α (HIF-1α) is considered critical for the stimulation of osteogenic markers including runt­related transcription factor 2 (Runx2), alkaline phosphatase (ALP) and osteocalcin, which are closely associated with forkhead boxclass O1 (Foxo1) levels in osteoblasts. The present study explored the associations between HIF­1α and Foxo1 in the regulation of cell viability, proliferation and apoptosis of osteoblasts. Osteoblasts obtained from children's iliac cancellous bone were used in the present study, which were confirmed by immunofluorescence staining for the osteoblast marker osteocalcin. The results revealed that the levels of reactive oxygen species and apoptosis were markedly increased in cells with knockdown of HIF­1α. By contrast, these were reduced in response to overexpressed HIF­1α. In addition, HIF­1α overexpression significantly stimulated cell viability, which was suppressed by silencing HIF­1α. HIF­1α overexpression also significantly increased the transcriptional and translational levels of Foxo1. Conversely, silencing HIF­1α markedly suppressed the expression levels of Foxo1. Furthermore, silencing HIF­1α reduced the expression of osteogenic markers, including Runx2, ALP and osteocalcin. Runx2 and ALP expression induced by HIF1α were markedly reversed by Foxo1 small interfering (si)RNA, whereas osteocalcin was not significantly affected by Foxo1 siRNA. Therefore, the cooperation of and interactions between HIF­1α and Foxo1 may be involved in the regulation of osteoblast markers, and serve a pivotal role in the proliferation and apoptosis of osteoblast. The HIF1α­induced expression of Runx2 and ALP may be completely dependent on the expression levels of Foxo1, and in turn, osteocalcin may be partially dependent on Foxo1 expression.

Genetic approaches to identify pathological limitations in aortic smooth muscle contraction.

Aortic smooth muscle contains limiting amounts of myosin light chain kinase (MLCK) for myosin regulatory light chain (RLC) phosphorylation and contraction that predisposes to thoracic aortic disease in humans containing heterozygous loss-of-function mutations in MYLK. We tested the hypothesis that thoracic aortic smooth muscle contraction may also be susceptible to variations in the smooth muscle-specific isoform of the motor protein myosin where inactivation of one Myh11 allele or the presence of one Myh11 missense variant associated with an increased risk of human aortic disease may result in a reduced force development response. Additionally, other kinds of smooth muscles may be less sensitive to the effects of mutations in one smooth muscle myosin allele, similar to results obtained with Mylk. Force development responses were reduced in aortic tissue from a conditional knockout of smooth muscle myosin heavy chain in adult mice (Myh11+/- or Myh11-/-) with a greater reduction with homozygous vs heterozygous tissues. Similar reductions in force responses were obtained with tissues containing either a heterozygous or homozygous knockin mutation in smooth muscle myosin heavy chain (Myh11+/R247C or Myh11R247C/R247C mutations that cause human aortic disease) with no significant changes in RLC phosphorylation. Agonist-dependent force responses were not reduced significantly in urinary bladder, ileal, or tracheal tissues from Myh11+/- mice while only ileal tissue showed a reduced force response in Myh11R247C/R247C mice. Thus, heterozygous mutations in Myh11 associated with reduced myosin function result in compromised contractile function primarily in aortic smooth muscle.

Evaluation of a Porous Bioabsorbable Interbody Mg-Zn Alloy Cage in a Goat Cervical Spine Model.

PURPOSE: Bioabsorbable Mg-based implants were previously assessed due to their intrinsic advantages, but Mg-based cage related research is limited. The specific blood supply and stress of the intervertebral environment can affect the function of Mg-based implants. The objective of this study was to investigate the performance of a bioabsorbable Mg-Zn alloy cage in anterior cervical discectomy and fusion (ACDF) and evaluate the control of degradation of the Mg-Zn cage surface modified by microarc oxidation (MAO) technology containing Si under an intervertebral microenvironment. METHODS: Twenty-four goats were divided into four groups according to the experimental period and all underwent ACDF at C2-3 and C4-5 with porous Mg-Zn cage covered with a MAO/Si-containing coating in one intervertebral space and with autologous iliac bone in another space. After 3, 6, 12, or 24 weeks after operation, the cervical spine specimens were harvested to evaluate the biocompatibility, fusion status, and degradation conditions using blood analysis, radiology, biomechanical testing, histology, and micro-CT. RESULTS: The Mg-Zn cages showed ideal biocompatibility and biomechanical characterization; however, the fusion state, as evaluated with radiology and histology, was not acceptable. Modified by the MAO/Si-containing coating, the degradation rate of the Mg-Zn cages was controllable but slower than expected. CONCLUSION: MAO/Si-containing coating Mg-Zn alloy cages demonstrated excessive control of degradation and fusion failure after 24 weeks postoperatively. We conclude that further studies should be designed to improve the using of Mg-based materials at the intervertebral space.

Osteocyte Protein Expression Is Altered in Low-Turnover Osteoporosis Caused by Mutations in WNT1 and PLS3.

Context: Osteocytes express proteins that regulate bone remodeling and mineralization. Objective: To evaluate the relationship between osteocyte-specific protein expression and bone histology in patients with monogenic osteoporosis due to wingless integration site 1 (WNT1) or plastin 3 (PLS3) mutations. Design and Setting: Cross-sectional cohort study at a university hospital. Participants: Six patients (four males; ages: 14 to 72 years) with a heterozygous WNT1 mutation and five patients (four males; ages: 9 to 70 years) with a heterozygous/hemizygous PLS3 mutation. Methods and Main Outcome Measures: Immunohistochemistry was performed for fibroblast growth factor 23 (FGF23), dentin matrix protein 1 (DMP1), sclerostin, and phosphorylated (phospho-)ß-catenin in iliac crest samples and compared with bone histomorphometry. Results: FGF23 expression in WNT1 patients was 243% that observed in PLS3 patients (P < 0.01). DMP1, sclerostin, and phospho-ß-catenin expression did not differ between groups. Serum phosphate correlated inversely with FGF23 expression (r = -0.79, P = 0.01) and serum ionized calcium correlated inversely with sclerostin expression (r = -0.60, P = 0.05). Phospho-ß-catenin expression correlated inversely with DMP1 expression (r = -0.88, P < 0.001), osteoid volume/bone volume (r = -0.68, P = 0.02), and bone formation rate (r = -0.78, P < 0.01). FGF23 expression did not correlate with DMP1 expression, sclerostin expression, or bone histomorphometry. Marrow adiposity was higher in WNT1 than in PLS3 patients (P = 0.04). Conclusions: Mutations that disrupt WNT signaling and osteocytic mechanosensing affect osteocyte protein expression. Abnormal osteocyte function may play a role in the pathogenesis of monogenetic forms of osteoporosis.

Cytomorphology of metastatic pituitary carcinoma to the bone.

Metastatic pituitary carcinoma to bone is rare. In this report, we present a case of a 59-year-old female with recurrent pituitary adenoma of the sparsely granulated somatotroph subtype with metastasis to a few bony sites 10 years later. Needle core biopsy (NCB) with touch preparations was performed on a 5 mm lesion in left ilium. Diff-Quik stained NCB touch preparation slides showed a few loosely cohesive epithelial polygonal cells that were arranged in nests or acini, or singly, had scant vacuolated cytoplasm and eccentrically located round nuclei (plasmacytoid) with slight nuclear pleomorphism, fine granular chromatin, conspicuous nucleoli, and smooth nuclear membrane. Trilineage hematopoietic cells of bone marrow were also appreciated in the background. H&E stained core sections showed fragments of bone and bone marrow with nests of bland epithelial cells with similar cytomorphology as seen in NCB touch preparation slides. The tumor cells were immunoreactive for juxtanuclear dot-like staining of pan-cytokeratin (CAM 5.2 and AE1/AE3) (a specific feature), neuroendocrine markers (CD56, synaptophysin, and chromogranin. Additionally, scattered cells were immunoreactive for growth hormone. Molecular test showed that tumor cells were negative for the promoter methylation of O-6-Methylguanine-DNA Methyltransferase (MGMT). Final diagnosis of metastatic pituitary carcinoma was rendered. Morphology of metastatic pituitary carcinoma, its differential, clinical presentation and treatment were discussed. Diagn. Cytopathol. 2017;45:645-650. © 2017 Wiley Periodicals, Inc.

Expression of Dlx-5 and Msx-1 in Craniofacial Skeletons and Ilia of Rats Treated With Zoledronate.

PURPOSE: Because of the different embryologic origins of the craniofacial skeleton and ilium, differences in gene expression patterns have been observed between the jaw bones and ilium. Distal-less homeobox (Dlx) genes and Msh homeobox genes, particularly Dlx-5 and Msx-1, play major roles in cell differentiation and osteogenesis. The purpose of this study was to investigate the effects of zoledronate (ZOL) on the craniofacial skeleton and ilium by detecting changes in Dlx-5 and Msx-1 expression at both the protein and messenger RNA levels. MATERIALS AND METHODS: A total of 24 female Sprague-Dawley rats were randomly divided into 2 groups: ZOL group (n = 12), in which the rats were injected intraperitoneally with zoledronic acid for 12 weeks, and control group (n = 12), in which the rats were injected with saline solution for 12 weeks. By use of immunohistochemistry, Western blotting, and real-time reverse transcription polymerase chain reaction, the expression levels of Dlx-5 and Msx-1 in the craniofacial skeleton (including the maxilla, mandible, and parietal bone) and ilium were examined. RESULTS: Dlx-5 expression in the maxilla and mandible was increased at the protein and messenger RNA levels in the ZOL group compared with the control group (P < .01). In addition, Msx-1 expression in the maxilla and mandible was decreased in the ZOL group (P < .01). Furthermore, Dlx-5 and Msx-1 expression in the ilium was decreased in the ZOL group (P < .05). However, no significant difference in Dlx-5 or Msx-1 expression in the parietal bone was observed between the 2 groups (P > .05). CONCLUSIONS: Site-specific differences in the effects of ZOL on the craniofacial skeleton and ilium could be explained by differently altered tendencies in Dlx-5 and Msx-1 expression. The jaw bones were more susceptible to the effects of ZOL than the parietal bone and ilium.

Lateral Ramus Cortical Bone Plate in Alveolar Cleft Osteoplasty with Concomitant Use of Buccal Fat Pad Derived Cells and Autogenous Bone: Phase I Clinical Trial.

Tissue regeneration has become a promising treatment for craniomaxillofacial bone defects such as alveolar clefts. This study sought to assess the efficacy of lateral ramus cortical plate with buccal fat pad derived mesenchymal stem cells (BFSCs) in treatment of human alveolar cleft defects. Ten patients with unilateral anterior maxillary cleft met the inclusion criteria and were assigned to three treatment groups. First group was treated with anterior iliac crest (AIC) bone and a collagen membrane (AIC group), the second group was treated with lateral ramus cortical bone plate (LRCP) with BFSCs mounted on a natural bovine bone mineral (LRCP+BFSC), and the third group was treated with AIC bone, BFSCs cultured on natural bovine bone mineral, and a collagen membrane (AIC+BFSC). The amount of regenerated bone was measured using cone beam computed tomography 6 months postoperatively. AIC group showed the least amount of new bone formation (70 ± 10.40%). LRCP+BFSC group demonstrated defect closure and higher amounts of new bone formation (75 ± 3.5%) but less than AIC+BFSC (82.5 ± 6.45%), suggesting that use of BFSCs within LRCP cage and AIC may enhance bone regeneration in alveolar cleft bone defects; however, the differences were not statistically significant. This clinical trial was registered at clinicaltrial.gov with NCT02859025 identifier.

Three-Dimensional Arrangement of Human Bone Marrow Microvessels Revealed by Immunohistology in Undecalcified Sections.

The arrangement of microvessels in human bone marrow is so far unknown. We combined monoclonal antibodies against CD34 and against CD141 to visualise all microvessel endothelia in 21 serial sections of about 1 cm2 size derived from a human iliac crest. The specimen was not decalcified and embedded in Technovit® 9100. In different regions of interest, the microvasculature was reconstructed in three dimensions using automatic methods. The three-dimensional models were subject to a rigid semiautomatic and manual quality control. In iliac crest bone marrow, the adipose tissue harbours irregularly distributed haematopoietic areas. These are fed by networks of large sinuses, which are loosely connected to networks of small capillaries prevailing in areas of pure adipose tissue. Our findings are compatible with the hypothesis that capillaries and sinuses in human iliac crest bone marrow are partially arranged in parallel.

A High-Adhesive Lysine-Cyclic RGD Peptide Designed for Selective Cell Retention Technology.

Cell adhesion is an important property of biomaterials used in selective cell retention (SCR) technology, which fabricates bone grafts rapidly in clinical settings. This could be improved by physical and biologic manipulations. To facilitate retention of the cells on the scaffold, especially osteoprogenitors from bone marrow in the convenient SCR procedure, a lysine-cyclic RGD (LcRGD) peptide was here designed to coordinate positively charged amino acids and the RGD sequence to enhance the adhesion performance of the scaffold. Demineralized bone matrix (DBM) is an important therapeutic resource, but its cell adhesion ability and osteoinductive capacity are low because of its processing. These capabilities can be increased to enhance the performance of DBM when used in SCR technology. Here, LcRGD peptide was used to modify DBM and produce a DBM/LcRGD composite. This composite exhibited enhanced adhesion performance on cultured human bone marrow-derived mesenchymal stem cells and retained more osteoprogenitors from bone marrow than other materials did. The DBM/LcRGD composite displayed a preferable osteoinduction in vitro and osteogenic capacity in vivo. Thus, LcRGD peptide as a commendable modifier of DBM applied in SCR technology can improve bone transplantation.

Examining the Relationships Between Bone Tissue Composition, Compositional Heterogeneity, and Fragility Fracture: A Matched Case-Controlled FTIRI Study.

Fourier transform infrared imaging (FTIRI) provides information on spatial distribution of the chemical composition of thin tissue specimens at ∼7 µm spatial resolution. This study of 120 age- and bone mineral density (BMD)-matched patients was designed to investigate the association of FTIRI variables, measured in iliac crest biopsies, with fragility fractures at any site. An earlier study of 54 women found hip BMD to be a significant explanatory variable of fracture risk for cortical bone but not for cancellous bone. In the current study, where age and BMD were controlled through matching, no such association was observed, validating the pairing scheme. Our first study of unmatched iliac crest biopsies found increases in collagen maturity (cancellous and cortical bone) and mineral crystal size (cortical bone only) to be a significant explanatory variable of fracture when combined with other covariates. The ratio for collagen maturity has been correlated to the amount of enzymatic collagen cross-links. To assess the impact of other FTIRI variables (acid phosphate substitution, carbonate-to-phosphate ratio, and the pixel distribution [heterogeneity] of all relevant FTIRI variables), we examined biopsies from a matched case-controlled study, in which 60 women with fractures were each paired with an age- and BMD-matched female control. With the matched data set of 120 women, conditional logistic regression analyses revealed that significant explanatory variables of fracture were decreased carbonate-to-phosphate ratio in both cancellous (odds ratio [OR] = 0.580, 95% confidence interval [CI] 0.37-0.909, p = 0.0176) and cortical bone (OR = 0.519, 95% CI 0.325-0.829, p = 0.0061), and increased heterogeneity (broadened pixel distribution) of collagen maturity for cancellous bone (OR = 1.549, 95% CI 1.002-2.396, p = 0.0491). The observation that collagen maturity was no longer linked to fracture in age- and BMD-matched samples suggests that age-dependent variation in collagen maturity may be a more important contributory factor to fragility fractures than previously thought. © 2015 American Society for Bone and Mineral Research.

Concentration profiling of minerals in iliac crest bone tissue of opium addicted humans using inductively coupled plasma and discriminant analysis techniques.

Opium addiction is one of the main health problems in developing countries and induces serious defects on the human body. In this work, the concentrations of 32 minerals including alkaline, heavy and toxic metals have been determined in the iliac crest bone tissue of 22 opium addicted individuals using inductively coupled plasma-optical emission spectroscopy (ICP-OES). The bone tissues of 30 humans with no physiological and metabolomic diseases were used as the control group. For subsequent analyses, the linear and quadratic discriminant analysis techniques have been used for classification of the data into "addicted" and "non-addicted" groups. Moreover, the counter-propagation artificial neural network (CPANN) has been used for clustering of the data. The results revealed that the CPANN is a robust model and thoroughly classifies the data. The area under the curve for the receiver operating characteristic curve for this model was more than 0.91. Investigation of the results revealed that the opium consumption causes a deficiency in the level of Calcium, Phosphate, Potassium and Sodium in iliac crest bone tissue. Moreover, this type of addiction induces an increment in the level of toxic and heavy metals such as Co, Cr, Mo and Ni in iliac crest tissue. The correlation analysis revealed that there were no significant dependencies between the age of the samples and the mineral content of their iliac crest, in this study. The results of this work suggest that the opium addicted individuals need thorough and restricted dietary and medical care programs after recovery phases, in order to have healthy bones.

Aging Versus Postmenopausal Osteoporosis: Bone Composition and Maturation Kinetics at Actively-Forming Trabecular Surfaces of Female Subjects Aged 1 to 84 Years.

Bone strength depends on the amount of bone, typically expressed as bone mineral density (BMD), determined by dual-energy X-ray absorptiometry (DXA), and on bone quality. Bone quality is a multifactorial entity including bone structural and material compositional properties. The purpose of the present study was to examine whether bone material composition properties at actively-forming trabecular bone surfaces in health are dependent on subject age, and to contrast them with postmenopausal osteoporosis patients. To achieve this, we analyzed by Raman microspectroscopy iliac crest biopsy samples from healthy subjects aged 1.5 to 45.7 years, paired biopsy samples from females before and immediately after menopause aged 46.7 to 53.6 years, and biopsy samples from placebo-treated postmenopausal osteoporotic patients aged 66 to 84 years. The monitored parameters were as follows: the mineral/matrix ratio; the mineral maturity/crystallinity (MMC); nanoporosity; the glycosaminoglycan (GAG) content; the lipid content; and the pyridinoline (Pyd) content. The results indicate that these bone quality parameters in healthy, actively-forming trabecular bone surfaces are dependent on subject age at constant tissue age, suggesting that with advancing age the kinetics of maturation (either accumulation, or posttranslational modifications, or both) change. For most parameters, the extrapolation of models fitted to the individual age dependence of bone in healthy individuals was in rough agreement with their values in postmenopausal osteoporotic patients, except for MMC, lipid, and Pyd content. Among these three, Pyd content showed the greatest deviation between healthy aging and disease, highlighting its potential to be used as a discriminating factor.