BACKGROUND: Despite the beneficial effect of fibroblast growth factor 21 (FGF21) on metabolic disease, there are concerns about adverse effects on bone metabolism, supported by animal studies. However, a recent human study showed the positive association between serum FGF21 level and bone mineral density (BMD) in healthy premenopausal women. We undertook this study to examine the association between FGF21 level and BMD in healthy postmenopausal Korean women who are susceptible to osteoporosis. METHODS: We used data of 115 participants from a cohort of healthy postmenopausal women (>50 years old) to examine the association between serum FGF21 level and BMD. The clinical characteristics were obtained from the participants, and blood testing and serum FGF21 testing were undertaken. BMD of the lumbar spine, femoral neck and total hip area, and bone markers were used in the analyses. RESULTS: The mean age of the participants was 60.2±7.2 years. Serum FGF21 levels showed negative correlation with BMD and T-scores in all three areas, but there were no statistically significant differences. Multivariate analyses with adjustment for age and body mass index also did not show significant association between serum FGF21 level and BMD. In addition, serum FGF21 level also showed no correlation with osteocalcin and C-telopeptide levels. CONCLUSION: In our study, serum FGF21 level showed no significant correlation with BMD and T-scores.
Animals ; Body Mass Index ; Bone Density* ; Cohort Studies ; Female ; Femur Neck ; Fibroblast Growth Factors* ; Fibroblasts* ; Hematologic Tests ; Hip ; Humans ; Metabolic Diseases ; Metabolism ; Multivariate Analysis ; Osteocalcin ; Osteoporosis ; Spine

Surface characteristics and cellular response to titanium surfaces that had been implanted with calcium and magnesium ions using plasma immersion ion implantation and deposition (PIIID) were evaluated. Three different titanium surfaces were analyzed: a resorbable blast media (RBM) surface (blasted with hydroxyapatite grit), a calcium ionimplanted surface, and a magnesium ion-implanted surface. The surface characteristics were investigated by scanning electron microscopy (SEM), surface roughness testing, X-ray diffraction (XRD), and Auger electron spectroscopy (AES). Human bone marrow derived mesenchymal stem cells were cultured on the 3 different surfaces. Initial cell attachment was evaluated by SEM, and cell proliferation was determined using MTT assay. Real-time polymerase chain reaction (PCR) was used to quantify osteoblastic gene expression (i.e., genes encoding RUNX2, type I collagen, alkaline phosphatase, and osteocalcin). Surface analysis did not reveal any changes in surface topography after ion implantation. AES revealed that magnesium ions were present in deeper layers than calcium ions. The calcium ion- and magnesium ion-implanted surfaces showed greater initial cell attachment. Investigation of cell proliferation revealed no significant difference among the groups. After 6 days of cultivation, the expression of RUNX2 was higher in the magnesium ion-implanted surface and the expression of osteocalcin was lower in the calcium ion-implanted surface. In conclusion, ion implantation using the PIIID technique changed the surface chemistry without changing the topography. Calcium ion- and magnesium ion-implanted surfaces showed greater initial cellular attachment.
Alkaline Phosphatase ; Bone Marrow* ; Calcium* ; Cell Proliferation ; Chemistry ; Collagen Type I ; Durapatite ; Gene Expression ; Humans* ; Immersion ; Ions* ; Magnesium* ; Mesenchymal Stromal Cells* ; Microscopy, Electron, Scanning ; Osteoblasts ; Osteocalcin ; Osteogenesis ; Plasma ; Real-Time Polymerase Chain Reaction ; Spectrum Analysis ; Titanium* ; X-Ray Diffraction

OBJECTIVE: Serum parameters of calcium homeostasis were measured based on previously published evidence linking osteoporotic fractures and/or bone/mineral loss with antipsychotics. METHODS: Prospective, four-week, time-series trial was conducted and study population consisted of patients of both genders, aged 35-85 years, admitted within the routine practice, with acute psychotic symptoms, to whom an antipsychotic drug was either introduced or substituted. Serial measurements of serum calcium, phosphorous, magnesium, 25(OH)D, parathyroid hormone, calcitonin, osteocalcin and C-telopeptide were made from patient venous blood samples. RESULTS: Calcium serum concentrations significantly decreased from baseline to the fourth week (2.42+/-0.12 vs. 2.33+/-0.16 mmol/L, p=0.022, n=25). The mean of all calcemia changes from the baseline was -2.6+/-5.7% (-24.1 to 7.7) with more decreases than increases (78 vs. 49, p=0.010) and more patents having negative sum of calcemia changes from baseline (n=28) than positive ones (n=10) (p=0.004). There were simultaneous falls of calcium and magnesium from baseline (63/15 vs. 23/26, p<0.001; OR=4.75, 95% CI 2.14-10.51), phosphorous (45/33 vs. 9/40, p<0.001; 6.06, 2.59-14.20) and 25(OH)D concentrations (57/21 vs. 13/35, p<0.001; 7.31, 3.25-16.42), respectively. Calcemia positively correlated with magnesemia, phosphatemia and 25(OH)D values. Parathyroid hormone and C-telopeptide showed only subtle oscillations of their absolute concentrations or changes from baseline; calcitonin and osteocalcin did not change. Adjustment of final calcemia trend (depletion/accumulation) for relevant risk factors, generally, did not change the results. CONCLUSION: In patients with psychotic disorders and several risks for bone metabolism disturbances antipsychotic treatment was associated with the decrease of calcemia and changes in levels of the associated ions.
Antipsychotic Agents* ; Blood Chemical Analysis ; Bone and Bones ; Calcitonin ; Calcium* ; Homeostasis ; Humans ; Ions ; Magnesium ; Metabolism* ; Minerals ; Osteocalcin ; Osteoporotic Fractures ; Parathyroid Hormone ; Prospective Studies ; Psychotic Disorders ; Risk Factors

Mesenchymal stem cells (MSCs) have been identified and isolated from dental tissues, including stem cells from apical papilla, which demonstrated the ability to differentiate into dentin-forming odontoblasts. The histone demethylase KDM6B (also known as JMJD3) was shown to play a key role in promoting osteogenic commitment by removing epigenetic marks H3K27me3 from the promoters of osteogenic genes. Whether KDM6B is involved in odontogenic differentiation of dental MSCs, however, is not known. Here, we explored the role of KDM6B in dental MSC fate determination into the odontogenic lineage. Using shRNA-expressing lentivirus, we performed KDM6B knockdown in dental MSCs and observed that KDM6B depletion leads to a significant reduction in alkaline phosphate (ALP) activity and in formation of mineralized nodules assessed by Alizarin Red staining. Additionally, mRNA expression of odontogenic marker gene SP7 (osterix, OSX), as well as extracellular matrix genes BGLAP (osteoclacin, OCN) and SPP1 (osteopontin, OPN), was suppressed by KDM6B depletion. When KDM6B was overexpressed in KDM6B-knockdown MSCs, odontogenic differentiation was restored, further confirming the facilitating role of KDM6B in odontogenic commitment. Mechanistically, KDM6B was recruited to bone morphogenic protein 2 (BMP2) promoters and the subsequent removal of silencing H3K27me3 marks led to the activation of this odontogenic master transcription gene. Taken together, our results demonstrated the critical role of a histone demethylase in the epigenetic regulation of odontogenic differentiation of dental MSCs. KDM6B may present as a potential therapeutic target in the regeneration of tooth structures and the repair of craniofacial defects.
Alkaline Phosphatase ; analysis ; Bone Morphogenetic Protein 2 ; genetics ; Bone Morphogenetic Protein 4 ; genetics ; Calcification, Physiologic ; genetics ; Cell Culture Techniques ; Cell Differentiation ; genetics ; Cell Lineage ; Dental Papilla ; cytology ; Epigenesis, Genetic ; genetics ; Gene Knockdown Techniques ; Homeodomain Proteins ; genetics ; Humans ; Jumonji Domain-Containing Histone Demethylases ; genetics ; Mesenchymal Stromal Cells ; physiology ; Odontoblasts ; physiology ; Odontogenesis ; genetics ; Osteocalcin ; analysis ; Osteopontin ; analysis ; Promoter Regions, Genetic ; genetics ; RNA, Small Interfering ; genetics ; Sp7 Transcription Factor ; Transcription Factors ; analysis ; genetics ; Transcriptional Activation ; genetics

Retaining or improving periodontal ligament (PDL) function is crucial for restoring periodontal defects. The aim of this study was to evaluate the physiological effects of low-power laser irradiation (LPLI) on the proliferation and osteogenic differentiation of human PDL (hPDL) cells. Cultured hPDL cells were irradiated (660 nm) daily with doses of 0, 1, 2 or 4 J⋅cm(-2). Cell proliferation was evaluated by the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay, and the effect of LPLI on osteogenic differentiation was assessed by Alizarin Red S staining and alkaline phosphatase (ALP) activity. Additionally, osteogenic marker gene expression was confirmed by real-time reverse transcription-polymerase chain reaction (RT-PCR). Our data showed that LPLI at a dose of 2 J⋅cm(-2) significantly promoted hPDL cell proliferation at days 3 and 5. In addition, LPLI at energy doses of 2 and 4 J⋅cm(-2) showed potential osteogenic capacity, as it stimulated ALP activity, calcium deposition, and osteogenic gene expression. We also showed that cyclic adenosine monophosphate (cAMP) is a critical regulator of the LPLI-mediated effects on hPDL cells. This study shows that LPLI can promote the proliferation and osteogenic differentiation of hPDL cells. These results suggest the potential use of LPLI in clinical applications for periodontal tissue regeneration.
Adenine ; analogs & derivatives ; pharmacology ; Adenylyl Cyclase Inhibitors ; Alkaline Phosphatase ; analysis ; genetics ; radiation effects ; Anthraquinones ; Bone Morphogenetic Protein 2 ; genetics ; Calcium ; metabolism ; radiation effects ; Cell Culture Techniques ; Cell Differentiation ; radiation effects ; Cell Line ; Cell Proliferation ; radiation effects ; Coloring Agents ; Core Binding Factor Alpha 1 Subunit ; genetics ; Cyclic AMP ; antagonists & inhibitors ; radiation effects ; Gene Expression ; radiation effects ; Humans ; L-Lactate Dehydrogenase ; analysis ; Lasers, Semiconductor ; Low-Level Light Therapy ; instrumentation ; Osteocalcin ; genetics ; Osteogenesis ; genetics ; radiation effects ; Periodontal Ligament ; cytology ; radiation effects ; Radiation Dosage ; Real-Time Polymerase Chain Reaction ; Reverse Transcriptase Polymerase Chain Reaction ; Tetrazolium Salts ; Thiazoles

OBJECTIVETo regenerate dentin-pulp complex by tissue engineering with human stem cells from apical papilla cells (SCAP) as the seed cells.

METHODSSCAP was separated from from normal human impacted third molars with immature roots by outgrowth culture. The cells were then cultured in the differentiation medium for 3 weeks or in normal medium for 60 days, and analyzed for mineralization potential by Alizarin red staining. The osteo/odontogenic markers including alkaline phosphatase (ALP), bone sialoprotein (BSP), osteocalcin (OC) and dentin sialoprotein (DSP) were investigated by immunofluorescence staining and reverse transcription-polymerase chain reaction. The co-cultured mixture of SCAP and HA/TCP, or HA/TCP alone was implanted subcutaneously on the back of nude mice for 8 weeks, and the implants were collected and examined by HE and immunohistochemical staining.

RESULTSRound alizarin red-positive nodules formed in the isolated cells after cell culture in the differentiation medium for 3 weeks or in normal medium for 60 days with positive staining for osteo/odontogenic markers. SCAP with HA/TCP could regenerate pulp-dentin complex-like tissue in nude mice. The cells near the dentin-like tissue were positive for DSP. No mineral tissue was found in mice receiving HA/TCP implantation.

CONCLUSIONSSCAP may serve as a promising seed cell for dentin-pulp complex tissue engineering.

Adolescent ; Adult ; Alkaline Phosphatase ; analysis ; Animals ; Cell Culture Techniques ; Cell Differentiation ; Coculture Techniques ; Dental Papilla ; cytology ; Dental Pulp ; cytology ; Extracellular Matrix Proteins ; analysis ; Female ; Humans ; Integrin-Binding Sialoprotein ; analysis ; Mice ; Mice, Nude ; Odontogenesis ; physiology ; Osteocalcin ; analysis ; Phosphoproteins ; analysis ; Sialoglycoproteins ; analysis ; Stem Cells ; chemistry ; physiology ; Tissue Engineering ; methods ; Young Adult

OBJECTIVETo observe effects of blood circulation promoting compounds combined with medicinal guides on content of bone glaprotein (BGP), bone morphogenetic protein-2 (BPM-2) and expression of BMP-2 mRNA in rabbits with femoral head necrosis, and explore its mechanism.

METHODSNinety-eight healthy Spragur-Dawley male rabbits were collected and weighted 2.2 to 2.8 kg. Eighty-four rabbits were built femoral head necrosis model by freezing left femoral head in liquid nitrogen, then randomly divided into 6 groups, 14 in each group. The 6 groups included model group,promoting blood circulation to remove meridian obstruction group,promoting blood circulation to remove meridian obstruction combined with achyranthes bidentata group,radix angelicae pubescentis, asarum group, and platycodon grandiflorum group,other 14 rabbits were sham operation group. While drug groups were administrated corresponding Chinese herb after molding,model group and shamp operation group were given saline. Recombinant human granulocyte-colony stimulating factor ( 30 microg x kg(-1) x d(-1))were injected into all rabbits for 7 days. Samples were taken on the second and fourth week,the content of BGP and BMP-2 were detected by enzyme-linked immunosorbent assay (ELSA) and radioimmunoassay (RIA), histopathological changes of left femoral head were observed by Hematoxylin and Eeosin staining (HE), and expression of BMP-2 mRNA were tested by fluorescence in situ hybridization.

RESULTSCompared with sham operation group, the rate of empty lacunae femoral head were obviously increased in model group, and the content of BGP were increased on the second week, and BMP-2 and BMP-2 mRNA were decreased on the fourth week. Compared with model group, the content of BGP, BMP-2 and BMP-2 mRNA were higher both of the second and fourth week in promoting blood circulation to remove meridian obstruction group. The rate of empty la- cunae femoral head were lower in achyranthes bidentata group, BGP, BMP-2 and BMP-2 mRNA were higher on the fourth week. The rate of empty lacunae femoral head were lower in platycodon grandiflorum group, and BGP were decreased on the second and fourth week, BMP-2 were lower on the second week ,while BMP-2 mRNA were decreased on the fourth week; the content of BMP-2 and BMP-2 mRNA were increased in radix angelicae pubescentis group on the second week; while there was no change in asarum group.

CONCLUSIONRadix angelicae pubescentis can increase the content of BGP, BMP-2 and expression of BMP-2 mRNA ,which is an effective mechanism of preventing femoral head necrosis.

Animals ; Blood Circulation ; drug effects ; Bone Morphogenetic Protein 2 ; analysis ; genetics ; Femur Head Necrosis ; drug therapy ; pathology ; physiopathology ; Male ; Meridians ; Osteocalcin ; blood ; Osteogenesis ; drug effects ; Rabbits

OBJECTIVETo establish a more stable method to isolate osteocytes in vitro, and then to find the differences with osteoblast biological characteristics.

METHODSOsteocytes and osteoblasts were isolated from the bone tissue of 3-day-old rats using sequential collagenase digestion. The cells were identified through cell morphology after 24 hours later. Alkaline phosphatase (ALP) kit was used to stain the first generation cells by Kaplow-way, the bone gla protein (BGP) of the cells were stained by immunocytochemitry. Measured ALP and computed its activity.

RESULTSOsteocytes and osteoblasts showed obviously differences in cell morphology. Osteocytes were star-shaped or dendrite-shaped within more dendrites, while osteoblasts were spindle-shaped with short dendrites. Osteocytes were negative for ALP, but osteoblasts were positive; Osteocytes were more positive for BGP, and osteoblasts were less positive. The secretion of ALP in osteocytes was lower than that of osteoblasts.

CONCLUSIONOsteocytes can be isolated and cultured in vitro. These characteristics of osteocytes are apparently difference with those of osteoblasts.

Alkaline Phosphatase ; analysis ; Animals ; Cell Separation ; methods ; Osteoblasts ; chemistry ; cytology ; Osteocalcin ; analysis ; Osteocytes ; chemistry ; cytology ; Rats ; Rats, Sprague-Dawley

PURPOSE: The purpose of this study was to evaluate the effect of alendronates on bone remodeling around titanium implant in the maxilla of rats. MATERIALS AND METHODS: The maxillary first molars were extracted and customized-titanium implants were placed immediately in thirty male Sprague-Dawley rats. The rats were divided into experimental (bisphosphonate) group and control group. At 4 weeks after implantation, the rats in the bisphosphonate group were subcutaneously injected with alendronate three times a week for 6 weeks where as the rats in control group were injected with saline. The rats were sacrificed at 1, 2, 3, 4, or 6 weeks after starting of injection and maxillary bones were collected subsequently. Alveolar bone remodeling around the implants were evaluated by radiographic and histologic analysis. Microarray analysis and immunohistomorphologic analysis were also performed on one rat, sacrificed at 6 weeks after starting of injection, from each group. Statistical analysis was performed using repeated measures analysis of variance and independent t test at a significance level of 5%. RESULTS: There was no statistically significant difference in the bone area (%) around implant between the bisphosphonate group and the control group. However, the amount of empty lacuna was significantly increased in the bisphosphonate group, especially in the rats sacrificed at 4 weeks after starting of injection compared to that of the corresponding control group. The bisphosphonate group showed the same level of TRAP positive cell count, osteocalcin and angiopoietin 1 as the control group. CONCLUSION: Alendronate may not decrease the amount of osteoclast. However, the significantly increased amount of empty lacuna in the bisphosphonate group may explain the suppression of bone remodeling in the bisphosphonate group.
Alendronate* ; Angiopoietin-1 ; Animals ; Bisphosphonate-Associated Osteonecrosis of the Jaw ; Bone Remodeling* ; Cell Count ; Humans ; Jaw ; Male ; Maxilla ; Microarray Analysis ; Molar ; Osteocalcin ; Osteoclasts ; Rats* ; Rats, Sprague-Dawley ; Titanium

BACKGROUND: We aimed to investigate the diagnostic utility of osteocalcin (OC), undercarboxylated osteocalcin (ucOC), and alkaline phosphatase (ALP) in pre- and postmenopausal women for femoral neck, L1-4, and L2-4 bone mineral density (BMD) values by taking into consideration their age, body mass index (BMI), and menopausal status. METHODS: Premenopausal (N=40) and postmenopausal cases (N=42) were classified as 25-34 or 35-45 yr of age and within the first 5 yr or 5 yr or more after the onset of menopause, respectively. RESULTS: Among the groups, statistical differences were found for age, BMI, OC, ucOC, ALP, femoral neck BMD, L1-4 BMD, and L2-4 BMD. The highest serum OC, ucOC, and ALP levels were observed in cases within the first 5 yr after the onset of menopause, probably due to a more rapid bone turnover rate. The best predictors for the femoral neck osteoporosis were ALP, OC, and calcium (areas under the ROC curve [AUC]=0.882, 0.829, and 0.761, respectively), and those for L1-4 and L2-4 osteoporosis were OC, ALP, and ucOC (AUC=0.949, 0.873, and 0.845; and 0.866, 0.819, and 0.814, respectively). Multiple logistic regression analysis revealed that the most discriminative parameter for osteoporosis was OC. CONCLUSIONS: These results indicate that serum OC levels, with or without ucOC and ALP, may be useful to monitor follow-up changes that currently cannot be assessed with BMD and to diagnose femoral neck, L1-4 spine, and L2-4 spine osteoporosis.
Adult ; Aged ; Alkaline Phosphatase/*blood ; Body Mass Index ; Bone Density ; Discriminant Analysis ; Female ; Follow-Up Studies ; Humans ; Logistic Models ; Middle Aged ; Osteocalcin/*blood ; Osteoporosis/blood/*diagnosis ; Osteoporosis, Postmenopausal/blood/diagnosis ; Postmenopause ; Premenopause