运动联合福善美对去卵巢大鼠骨密度和神经传导的影响

目的: 观察运动是否可增强福善美对卵巢切除大鼠骨质疏松的治疗作用。方法: 将90只6月龄雌性SD大鼠随机分为假手术组(sham,18只)和卵巢切除模型组(OVX,72只)。大鼠卵巢切除8周后,测定大鼠第4腰椎骨密度(BMD)和血清雌二醇含量。随后,存活的OVX大鼠分为模型组(OVX)、福善美治疗组(OVX+FOX)、运动治疗组(OVX+EX)和福善美与运动联合治疗组(OVX+FOX+EX),分别给予1 mg·kg^-1·d^-1福善美灌胃和(或)跑台运动干预治疗12周后,双能X线骨密度仪测定各组大鼠第4腰椎BMD;肌电图机检测大鼠左侧股神经传导速度(MCV)、运动末端潜伏期(ML)和复合肌肉动作电位(CMAP);ELISA法测定大鼠血清Ⅰ型前胶原羧基端前肽(PICP)及Ⅰ型胶原羧基端交联端肽(ICTP)含量。结果: 卵巢切除大鼠福善美和(或)运动干预治疗12周后,OVX组与sham组相比,BMD显著降低(P<0.05),血清PICP和ICTP明显增高(P<0.05),左侧股神经ML未见明显改变。福善美和运动均可显著提高骨质疏松大鼠BMD,降低ICTP;福善美可显著降低骨质疏松大鼠ICTP,而运动对ICTP无明显影响。运动可明显缩短模型组左侧ML(P<0.05),福善美对ML无显著改善作用。运动与福善美联合对BMD、PICP、ICTP及ML的改善作用较两者单用效果显著(P<0.05);福善美与运动两治疗组间未见明显差异。各组大鼠左侧股神经MCV和CMAP未见明显差异。2×2析因设计的方差分析显示,福善美与运动2种处理方式之间不存在交互作用(P>0.05)。结论: 福善美和运动可能通过抑制破骨细胞的骨吸收而抑制大鼠卵巢切除对骨密度的影响。     

Reduced bone mineral density and low parathyroid hormone levels in patients with the adult form of hypophosphatasia

Summary Hypophosphatasia is a heritable metabolic bone disease with characteristically reduced levels of alkaline phosphatase (ALP) in the blood, liver, kidney and bone. ALP levels are normal in the intestine and placenta. About 300 patients have been reported so far in the literature. Three kindreds with 52 known subjects are described here, whereby 12 subjects could be examined osteologically. Four subjects were patients and had clinical signs of the disease: spontaneous fractures of the metatarsals or femora and low ALP serum levels ranging between 8 and 23 U/1 (normal range 40–170 U/1). Four other members without fractures had reduced ALP levels; they might be carriers of the disease and develop symptoms later in life. The four remaining subjects had normal ALP levels and no signs of the disease. Serum levels of intact parathyroid hormone (iPTH) were found to be in the lower normal range and serum calcium levels in the upper normal range. There was a significant (P<0.05) negative correlation between iPTH and serum calcium levels (r=–0.78). Urinary calcium excretion was increased in 3 subjects with fractures. 25-OH-D₃ levels were increased in 6 of 8 subjects without any treatment. The bone mineral density (BMD) was measured using dual X-ray absorptiometry of the lumbar spine, representing mainly trabecular bone, and single-photon absorptiometry of the forearm, measuring mainly cortical bone. Z-scores of the spinal bone mass ranged between 0.38 and –1.95 SD; Z-scores of the forearm bone mass ranged between 0.53 and –2.47 SD with the lowest values in patients with fractures. There was a significant (P<0.05) correlation between serum ALP levels and forearm BMD (r=0.83). We conclude from these data that patients with the adult form of hypophosphatasia have decreased forearm and subnormal spinal bone mass, as well as reduced serum levels of iPTH.Abbreviations BMD bone mineral density - ALP alkaline phosphatase - iPTH intact parathyroid hormone - 25-OHD₃ 25-hydroxyvitamin D₃ - SD standard deviation - PEA phosphoethanolamine - PPi inorganic pyrophosphate - PLP pyridoxal-5-phosphate - cDNA clonal desoxyribonucleic acid - U/S Ca²⁺ urinary/serum calcium - DXA dual X-ray absorptiometry - DPA dual photon absorptiometry - SPAD bone density of distal forearm measured by single photon absorptiometry - SPAP bone density of proximal forearm measured by single photon absorptiometry     

骨转换生化标志物在DM2并发骨质疏松的临床应用价值

目的:探讨骨转换生化标志物在2型糖尿病(DM2)患者并发骨质疏松的早期诊断价值.方法:选择112例DM2患者,根据受试者的骨密度值分为骨质疏松组和非骨质疏松组,对比两组DM2患者的总Ⅰ型前胶原氨基端延长肽(TPINP)、Ⅰ型胶原羧基端肽β特殊序列(β-CTx)、甲状旁腺素(PTH)和血清钙(Ca2+)指标之间的差异.结...     

Serum leptin levels,bone mineral density and osteoblast alkaline phosphatase activity in elderly men and women

Although primarily secreted by adipose cells, leptin, a polypeptide hormone that influences body weight, satiety and lipid metabolism, and its receptor are also expressed in human osteoblasts. Leptin plays a role in the central, hypothalamic modulation of bone formation, as well as locally within the skeleton by enhancing differentiation of bone marrow stroma into osteoblasts and inhibiting its differentiation into osteoclasts and adipocytes. The purpose of this investigation was to compare serum leptin values in 100 postmenopausal women (age 62-97) and 31 men (age 72-92) to bone mineral density (BMD) measurements made by dual X-ray absorptiometry and additionally to biochemical markers of bone resorption and formation, including crosslinked collagen N-telopeptides (NTx), aminoterminal extension procollagen propeptides (PINP) and bone-specific alkaline phosphatase (bAP). The circulating level of leptin directly correlated with body mass index (BMI) (r=0.61-0.78, P<0.001) and was modestly, but significantly and positively associated with bAP activity (r=0.24-0.33, P<0.01) in the sera of men and women after adjustment for BMD, age and BMI. The association of circulating leptin levels with bAP, a specific marker of osteoblast activity suggests that leptin levels influence osteoblast activity in vivo in elderly women and men.     

骨转换生化标志物在慢性肾脏病患者中的临床应用价值

目的:探讨骨转换生化标志物在慢性肾脏病患者并发肾性骨营养不良的早期诊断价值。方法:分别检测102例慢性肾脏病（CKD）患者和52例健康成年人血清中骨转换生化标志物总Ⅰ型前胶原氨基端延长肽（TPⅠNP）、Ⅰ型胶原羧基端肽β特殊序列（β-CTx）、完整甲状旁腺素（iPTH）及血清钙(Ca²⁺)、血清磷（P）指标之间的差异。结果:CKD患者TPⅠNP、β-CTx、iPTH、P均高于正常对照组（P<0.05或P<0.01）,血清Ca²⁺明显地低于正常对照组（P<0.05）。结论:联检骨转换生化指标TPⅠNP和β-CTx可有助于对CKD患者并发肾性骨营养不良的早期诊断。     

Markers of collagen synthesis and degradation in urogenital tissue and serum from women with and without uterovaginal prolapse

Diverging results have been published concerning collagen metabolism in uterovaginal prolapse (UP). We have investigated collagen turnover in urogenital tissue in urologically healthy women with (UP patients) and without UP or any history of UP (controls). Markers of collagen turnover, carboxy-terminal propeptide of type I procollagen (PICP), amino-terminal propeptide of procollagen III (PIIINP) and carboxy-terminal telopeptide of type I collagen (ICTP) were assayed in urogenital tissue homogenates and serum. Tissue and serum concentrations of collagen turnover markers were related to UP and to menopausal/estrogen status. UP patients were significantly older than the controls. UP patients had significantly higher tissue PICP and PIIINP and significantly lower tissue ICTP levels than the controls, but the difference in ICTP disappeared after matching for menopausal/estrogen status and age. There were no associations between tissue collagen turnover markers on the one hand and menopausal/estrogen status or age on the other. The higher tissue concentrations of PICP and especially PIIINP in tissue from women with UP compared to controls, suggest an increased collagen breakdown in UP. This pattern differs from that in stress urinary incontinent women without UP, where tissue levels of collagen turnover markers are low, indicating reduced collagen breakdown.     

Association between leptin,markers of bone formation and physical growth of newborns

Background : The increase of body size and weight depends on metabolism in the bone tissue and accumulation of fat, but the role of many hormones and enzymatic systems that may influence these processes significantly has not been recognized. Aim : An attempt to assess the correlation between the leptin hormone taking part in the regulation of fat tissue reserves, markers of bone formation and selected anthropometric traits in newborns was made. Subjects and methods : Levels of leptin, osteocalcin and C-terminal propeptide type I procollagen (PICP) in the serum of 64 Appropriate for Gestational Age newborns (AGA newborns) with gestational age between 27 and 42 weeks were assessed. In parallel, 15 anthropometric traits were measured and the Quetelet Index was calculated for all the newborns. Statistical analysis was performed using the Student's t -test, Mann-Whitney U test, Pearson's correlation and Spearman's correlation rank test. p < 0.05 was regarded as significant. Results : Statistically significant correlations between leptin, osteocalcin, PICP and selected anthropometric traits in newborns were found. There were no statistically significant correlations between serum levels of leptin and markers of bone formation in the investigated group of children. Conclusion : In our study, we documented the association of leptin, osteocalcin and PICP with overall physical growth of AGA newborns. We did not confirm the relationship between leptin and bone formation in this stage of ontogenesis.     

Disturbed calcium metabolism in subjects with elevated diastolic blood pressure

Summary Essential hypertension has been associated with disturbed calcium metabolism, but the available data are controversial. We measured parameters of calcium metabolism in groups of untreated male subjects (n = 78) with elevated diastolic blood pressure (101 ± 6 mmHg, mean ± SD) and age-matched male subjects (n=79) with low diastolic blood pressure (62 ± 4 mmHg). The participants of the study were drawn from a random population sample. Subjects with high diastolic blood pressure had significantly higher carboxy-terminal parathyroid hormone (PTH) plasma concentrations than controls with low diastolic blood pressure (median 114 vs. 43 pmol/l, P < 0.01). The 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D concentrations were comparable in both groups. Individuals with high diastolic blood pressure had significantly lower total serum calcium (2.41 ± 0.10 vs. 2.47 ± 0.10 mmol/l, mean ± SD; P < 0.01). PTH concentrations were correlated with diastolic pressure (r = –0.39, P < 0.001). The data are compatible with increased parathyroid activity despite unchanged concentrations of vitamin D metabolites in human hypertension.Abbreviations PTH parathyroid hormone - C-PTH carboxy-terminal parathyroid hormone - 1,25(OH)₂D 1,25-di-hydroxyvitamin D - 25(OH)D 25-hydroxyvitamin D     

Peripheral and axial bone mass in Austrian free climbers

Summary The present investigation was carried out in healthy white adult males to determine the effects of exercise, in the form of free climbing, on peripheral and axial bone mass.13 men who have been regularly engaging in alpine free climbing for a mean period of nine years and, for training purposes, have been performing additional muscle building exercises (4.5 h±1 SEM per week) and 12 age matched controls were included in the study. Bone mineral content of the non-dominant distal forearm was measured by single-photon absorptiometry, and bone mineral density of the lumbar spine was determined by quantitative computed tomography.It was found that consistent exercise in the form of alpine free climbing was associated with increased bone mass of the lumbar spine (162.4 ±4.4 vs 184.8 ±7.9 mg/ml, p< 0.025). Peripheral bone mineral content of the distal forearm was slightly but not significantly increased in the free climbers (55.4 ±9.0 vs 61.1±7.4 Units, p<0.09 N.S.).The study provides additional evidence that exercise in the form of alpine climbing, is associated with increased lumbar bone mass.Abbreviations BMC bone mineral content - SPA single-photon absorptiometry - BMD bone mineral density - QCT quantitative computed tomography     

Association between leptin,markers of bone formation and physical growth of newborns

BACKGROUND: The increase of body size and weight depends on metabolism in the bone tissue and accumulation of fat, but the role of many hormones and enzymatic systems that may influence these processes significantly has not been recognized. AIM: An attempt to assess the correlation between the leptin hormone taking part in the regulation of fat tissue reserves, markers of bone formation and selected anthropometric traits in newborns was made. Subjects and methods: Levels of leptin, osteocalcin and C-terminal propeptide type I procollagen (PICP) in the serum of 64 Appropriate for Gestational Age newborns (AGA newborns) with gestational age between 27 and 42 weeks were assessed. In parallel, 15 anthropometric traits were measured and the Quetelet Index was calculated for all the newborns. Statistical analysis was performed using the Student's t-test, Mann-Whitney U test, Pearson's correlation and Spearman's correlation rank test. p < 0.05 was regarded as significant. RESULTS: Statistically significant correlations between leptin, osteocalcin, PICP and selected anthropometric traits in newborns were found. There were no statistically significant correlations between serum levels of leptin and markers of bone formation in the investigated group of children. CONCLUSION: In our study, we documented the association of leptin, osteocalcin and PICP with overall physical growth of AGA newborns. We did not confirm the relationship between leptin and bone formation in this stage of ontogenesis.     

Relationship between hemostatic markers and circulating biochemical markers of collagen metabolism in patients with aortic aneurysm

Our objective was to determine the relationship between plasma levels of hemostatic molecular markers--D-dimer and thrombin-antithrombin III complex (TAT)--and circulating biochemical markers of collagen metabolism--aminoterminal propeptide of type III procollagen (PIIIP) and carboxyterminal propeptide of type I procollagen (PICP)--in patients with aortic aneurysm. The subjects were 43 patients with aortic aneurysm (AA; mean age 71 years) and 26 age-matched controls (mean age 75 years). The mean D-dimer, TAT and PIIIP levels were higher in the patients than in the controls (p < 0.0001, 0.0001 and 0.012, respectively), while the mean PICP level was similar to that in the controls. Increased D-dimer had a significant correlation with PIIIP (r = 0.412, p = 0.006) and PICP (r = 0.342, p = 0.0246), while TAT correlated with PIIIP (r = 0.3194, p = 0.0374), but not with PICP. There was also a significant correlation (r = 0.306, p = 0.0463) between PIIIP and PICP. As shown by the significant positive correlations among D-dimer, TAT and PIIIP, accelerated fibrinolysis and thrombogenesis induce an increase of collagen degradation and procollagen synthesis in atherosclerotic lesions. These findings show that D-dimer and TAT, especially the former, may be useful markers to monitor the progression and predict the prognosis of AA.     

Association of KIT gene polymorphisms with bone mineral density in postmenopausal Korean women

Bone mineral density (BMD) is a major factor for determining bone strength and osteoporotic fracture risk, and is determined by environmental and multiple genetic factors. KIT, which encodes a transmembrane receptor with tyrosine kinase activity, plays an important role in the differentiation of osteoclasts. We examined the associations between KIT gene polymorphisms and BMD in postmenopausal Korean women. All exons, their boundaries, and the promoter region (approximately 1.5 kb) from 24 individuals were directly sequenced. Eighteen polymorphisms were identified, and three single-nucleotide polymorphisms (SNPs) were genotyped in all study participants (n = 946). BMD at the lumbar spine and femoral neck was measured using dual-energy X-ray absorptiometry. The mean age of the study subjects was 58.9 ± 7.5 years, and the mean number of years since menopause was 9.6 ± 7.9 years. None of the three SNPs (−1694G>T, +41894A>G, and +49512G>A) was significantly associated with BMD value. However, multivariate analysis showed that the ht3 (−1694T-+41894A-+49512G) was significantly associated with lower BMD at the femoral neck (P = 0.007 in the recessive model). These findings indicate that KIT-ht3 may be a useful genetic marker for osteoporosis and that KIT may have a role on bone metabolism in humans. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. S.-Y. Kim and J.-Y. Lee are co-first authors.     

Effects of inhaled budesonide on serum markers of bone metabolism in children with asthma.

The effects of inhaled glucocorticoids on serum markers of bone formation were evaluated in asthmatic children. Serum total alkaline phosphatase (AP), bone alkaline phosphatase (BAP), osteocalcin, and the novel marker of bone formation, carboxypropeptide of type I procollagen (PICP), were measured. In the cross-sectional part, long-term glucocorticoid users were compared with sodium cromoglycate (SCG) users. In the boys (n = 16), but not in the girls (n = 11), PICP was significantly lower in the glucocorticoid users than in the SCG users. PICP correlated positively with BAP (n = 54; groups combined, r = 0.29, p < 0.05). In the longitudinal part, the effects of inhaled budesonide or SCG, both used for the first time, were evaluated before and after 1 and 5 months of treatment. The budesonide dose was 800 micrograms/m2/day for 1 month and thereafter half of that. The SCG dose was 30 mg/day throughout the study. Only during budesonide use did osteocalcin and PICP decrease, the median osteocalcin by 8% at 1 month (p < 0.05) and by 6% at 5 months (n = 15), and PICP by 5% at 1 month (p < 0.05) and by 28% at 5 months (n = 7, p < 0.01). AP and BAP did not change significantly. Decreased PICP suggests decreased bone formation rate. PICP might be clinically useful as a marker of early adverse effects of glucocorticoids on bone.     

Activin A circulating levels in patients with bone metastasis from breast or prostate cancer

Recent studies have highlighted that Activin A, a member of the transforming growth factor-β (TGF-β) superfamily, may be involved in the regulation of osteoblastic activity and in osteoclast differentiation. Therefore, we have investigated the clinical significance of its circulating levels in patients with bone metastasis. Activin A serum concentrations were determined, by a commercially available enzyme-linked immunosorbent assay kit, in 72 patients with breast cancer (BC) or prostatic cancer (PC) with (BM+) or without (BM−) bone metastases, in 15 female patients with age-related osteoporosis (OP), in 20 patients with benign prostatic hypertrophy (BPH) and in 48 registered healthy blood donors (HS) of both sex (25 female and 23 male). Activin A serum concentrations were significantly increased in BC or PC patients as compared to OP (P < 0.0001) or BPH (P = 0.045), respectively, or to sex matched HS (P < 0.0001). Additionally, these levels resulted more elevated in PC patients as compared to BC patients (P = 0.032). Interestingly, Activin A was significantly higher in BM+ patients than in BM− patients (BC, P = 0.047; PC, P = 0.016). In BC patients, a significant correlation was observed only between Activin A and number of bone metastases (P = 0.0065) while, in PC patients, Activin A levels were strongly correlated with the Gleason score (P = 0.011) or PSA levels (P = 0.0001) and, to a lessen extent, with the number of bone metastases (P = 0.056). Receiver operating characteristic curve (ROC) analysis showed a fair diagnostic accuracy of Activin A to discriminate between BM+ and BM− patients (BC: AUC = 0.71 ± 0.09, P = 0.03; PC: AUC = 0.73 ± 0.081, P = 0.005). These findings indicate that Activin A may be implicated in the pathogenesis of bone metastasis. Therefore, this cytokine may be considered a novel potential target for a more selective therapeutic approach in the treatment of skeletal metastasis and may be also useful as additional biochemical marker of metastatic bone disease.     

Bone metabolism in elite male rowers: adaptation to volume-extended training

We examined the effect of 6-month volume-extended training on bone metabolism in elite male rowers. Twelve elite male rowers (20.8±3.0 years; 192.9±4.7 cm; 91.9±5.3 kg; body fat 10.1±2.3%; 6.2±0.5 l min⁻¹) participated in this study. Bone biochemical markers, hormones, bone mineral content (BMC), and bone mineral density (BMD) were assessed before and after training. Average weekly training volume was significantly higher (P<0.05) during the 6 months of heavy training compared to relative rest (11.6±0.4 h week⁻¹ vs. 16.8±0.6 h week⁻¹), while intensity remained the same. At the end of training, only arm BMD was significantly increased by 5.7%. Osteocalcin (16.6%), insulin-like growth factor-1 (IGF-1) (20.2%) and the bioavailability IGF-1 index (17.9%) were significantly increased. Before heavy training, relationships were observed between the whole body BMD and growth hormone (r=0.64; P≤0.02), lumbar spine BMD and 1.25(OH)₂ vitamin D (r=0.69; P≤0.04), arm BMD and testosterone (r=0.59; P≤0.05), and arm BMD and adiponectin (r=0.59; P≤0.05). No relationship was found between BMC or BMD and blood biochemical measures 6 months later (r=0.56; P≥0.05). In addition, osteocalcin was related to IGF-1 (r>0.58; P<0.048) and bioavailability IGF-1 index (r>0.59; P≤0.055) before and after training. In summary, heavy training had a moderately favorable effect on BMD. Bone tissue at specific skeleton sites is sensitive to changes in training volume even in athletes with already high BMD values. Changes in BMD and bone formation may be caused by changes in specific hormones such as IGF-1 and adiponectin in male athletes.     

Skeletal alterations in hypophysectomized rats: II. A histomorphometric study on tibial cortical bone

Background: Pituitary hormones play an important role in bone growth, modeling, and remodeling. The purpose of this study is to examine the effect of hypophysectomy (HX) on tibial cortical bone with histomorphometry. Methods: Forty-Five female Sprague-Dawiey rats, at 3 months of age, were hypophysectomized or served as intact controls. They were sacrificed at 0, 2, and 5 weeks after the surgery. Cortical bone histomorphometry was performed on double-fluorescent-labeled 30-mcm-thick sections of the tibial shaft. Results: The dry weight and density of tibial diaphysis and the cortical bone area of the tibial shaft in the HX rats were significantly lower (P<0.05) than that of the age-matched intact rats, but did not differ between the HX and basal control rats. The dynamic data show that the bone formation parameters (labeled surface, mineral apposition rate, and bone formation rate) were profoundly decreased (P<0.01) on both the periosteal and endocortical surfaces in the HX rats as compared with the age-matched intact rats at the 2 and 5 weeks. However, the decrease in the labeled surface was much less on the endocortical envelope than on the periosteal envelope in the HX rats. Although no significant change was detected in the medullar size between the HX and age-matched intact rats, the eroded surface on the endocortical surface was greater (P<0.05) in the HX rats than in the intact rats at either time point. Conclusions: Hypophysectomy-suppressed, radial growth-dependent bone gain without a bone loss in the tibial shaft of the young rat. This is associated with decreased modeling-dependent bone formation. A greater eroded surface on the endosteum did not affect the marrow size at 5 weeks after hypophysectomy. © 1995 Wiley-Liss, Inc.     

Type I collagen as a marker of bone metabolism in sickle cell hemoglobinopathies.

Avascular necrosis of the skeletal system is a complication of sickle cell hemoglobinopathies. Type I collagen, which is synthesized by osteoblasts, comprises about 90% of the total organic matrix of bone. This preliminary study of skeletal changes in sickle cell hemoglobinopathies measured type I collagen formation and degradation using specific radioimmunoassays to determine the plasma concentrations of carboxyterminal propeptide of type I procollagen (PICP) and carboxyterminal pyridinoline cross-linked telopeptide of type I collagen (ICTP), respectively. Plasma ICTP concentrations were increased significantly in sickle cell patients with no clinical or radiologic symptoms of bone complications than in controls. Mean plasma ICTP concentration was moderately high in all patients. Plasma PICP levels did not differ significantly between patients and controls. This preliminary results indicate that measurements of plasma ICTP might be helpful in predicting bone changes in sickle cell hemoglobinopathies and also useful in the early detection of skeletal complications of the disease.     

循环轴向压缩应力增强基质依赖型组织工程骨骨再生能力的研究

目的 研究循环轴向压缩应力（CACS）对基质依赖型组织工程骨（M-TEB）骨再生能力的影响。方法 首先,在构建静态M-TEB过程中加载CACS,得到动态M-TEB;然后,对各组M-TEB进行表征,并构建动物模型来评价其骨再生能力;最后,通过转录组测序探究CACS对骨髓间充质干细胞（BMSCs）基因表达的影响,并研究M-TEB来源条件培养基对内皮祖细胞（EPCs）迁移、增殖和对BMSCs成骨分化的影响。结果 ①动态M-TEB组在骨缺损区有更多新骨生成,且骨体积分数和骨密度均显著优于假手术组和静态M-TEB组（P均＜0.01）;②前30个有显著差异（q＜0.01）的基因本体论（GO）术语主要涉及MAPK通路、细胞凋亡和血管生成等,且差异基因VEGFA在这些GO术语中出现频次最高（28次）;③相比静态M-TEB来源条件培养基,动态M-TEB来源条件培养基具有更强的促进EPCs迁移、增殖和BMSCs成骨分化的作用（P均＜0.05）, 阻断实验证实VEGFA在其中发挥重要功能。结论 CACS促进BMSCs表达和分泌VEGFA,提高动态M-TEB中VEGFA浓度,最终增强其在大鼠股骨缺损模型中的骨再生能力。     

Formation of osteoblast-like cells from human mononuclear bone marrow cultures

Osteoblast-like cells are commonly found in the vicinity of osteoclasts formed in long-term human bone marrow cultures, and they are believed to be derived from osteogenic cell precursors belonging to the stromal cell system. This paper describes a new culture method for human osteoblasts from the adherent cell population of long-term human mononuclear bone marrow cultures. The cells obtained exhibited all the classic characteristics of osteoblasts. They contained high intracellular concentrations of alkaline phosphatase and they secreted the osteoblast-specific marker bone Gla protein. Collagen production was mainly (95-98%) procollagen type I propeptide and only minute quantities of procollagen type III propeptide were detectable by radioimmunoassay in the conditioned medium. After eight weeks the cells formed a mineralized matrix on exposure to beta-glycerophosphate and ascorbic acid. This system provides a model for the study of osteoblast differentiation in vitro and may form the basis for the use of defined media in bone cell cultures due to the presence of high concentrations of osteoblast precursors.