Use of biochemical markers to monitor changes in bone turnover in cynomolgus monkeys.

The ovariectomized old cynomolgus monkey is a recognized model of human osteoporosis, and the same species can be used for the assessment of the efficacy and potential toxicity of agents intended to prevent or treat osteoporosis. Several assays have been developed that can measure the same biochemical markers of bone turnover as are used in human patients for the diagnosis and treatment follow-up of bone-related diseases, including osteoporosis. The aim of the present study was to describe the results obtained with these assays in normal control monkeys, their variations with age and sex, and their sensitivity in monitoring the bone turnover induced by ovariectomy in old skeletally mature cynomolgus monkeys. Seven old cynomolgus monkeys were bilaterally ovariectomized and 13 age-matched monkeys were sham-operated. Bone mineral density and biochemical markers were measured before and at regular intervals after surgery for up to 20 months. Total alkaline phosphatase (total ALP), bone-specific alkaline phosphatase isoenzyme (bone ALP) and osteocalcin (OC) were highly correlated to the decrease in bone mineral density (BMD) induced by ovariectomy. Deoxypyridinoline (DPD) measured by enzyme-linked immunoassay was insensitive to the bone resorption induced by ovariectomy, but cross-linked N-telopeptide (NTX-I) was higher in ovariectomized monkeys than in control monkeys. These results demonstrate that reliable biochemical parameters are available to adequately monitor and provide insight into osteoclastic bone resorption and osteoblastic bone formation, the two components of bone turnover in this animal model, and can thus be used to assess the efficacy and toxicity of potential therapeutic agents.     

Intrauterine growth restriction affects bone mineral density of the mandible and the condyle in growing rats

Objectives:To investigate in growing rats the effect of intrauterine growth restriction (IUGR) on the bone mineral density of the mandible and tibia, as well as the quality of the mandibular and condylar bone.Methods:Twelve male rats were born IUGR by mothers sustaining 50% food restriction during pregnancy. Twelve control male rats were born by mothers fed ad libitum. Dual-energy X-ray absorptiometry (DEXA) of the tibia, proximal tibial metaphysis and the mandible, biochemical markers, histology and histomorphometrical analysis on the mandibular and subchondral bone of the condyle were performed.Results:IUGR significantly affected bone mineral density (BMD) of both tibial and mandibular bones. IUGR rats had significantly lower osteocalcin values (p=0.021) and phosphorus (p=0.028), but not 25-OH vitamin D (p=0.352). Bone area percentage in the mandible was significantly lower (51.21±5.54) in IUGR compared to controls (66.00±15.49), and for subchondral bone of the condyle for IUGR (47.01±6.82) compared to controls (68.27±13.37). IUGR had a significant reduction in the fibrous layer, but not the proliferating layer, with the hypertrophic layer significantly increased.Conclusion:Maternal restricted nutrition during gestation can affect BMD of the mandible and the tibia of the offspring animals.     

Comparison between liraglutide alone and liraglutide in combination with insulin on osteoporotic rats and their effect on bone mineral density

Objectives:To compare the therapeutic efficacy of liraglutide (LRG) single drug combined with insulin (Ins) on osteoporosis in rats and its effect on bone mineral density (BMD). A rat model of diabetes combined with osteoporosis was established.Methods:40 Sprague-Dawley rats were divided into four groups (blank, control, LRG and LRG+Ins). Serum levels of CrossLaps, procollagen type I N propeptide (PINP), alkaline phosphatase (AKP) and osteocalcin (BGP) were detected by ELISA. Blood glucose was measured by its reaction with glucose oxidase. Serum insulin was analyzed by radioimmunology. Bone calcium and phosphorus contents were also recorded. ELISA was used to detect inflammatory factors. Bone mineral density (BMD) measurement was also performed.Results:BMD of the control group was significantly lower than that of the other three groups (p<0.05) and BMD of the LRG + Ins group was significantly higher than that of the LRG group (p<0.05). The inflammatory factors of the control group were significantly higher than those in the other three groups (p<0.05). The inflammatory factors were negatively correlated with BMD (p<0.05).Conclusions:liraglutide in combination with insulin for the treatment of diabetes complicated with osteoporosis can reduce blood glucose in vivo, promote production of islet, effectively improve osteoporosis symptoms, increase BMD and reduce the levels of inflammatory factors in vivo.     

The association between major depressive disorder,use of antidepressants and bone mineral density (BMD) in men

Objective:

Both depression and use of antidepressants have been negatively associated with bone mineral density (BMD) but mainly in studies among postmenopausal women. Therefore, the aim of this study was to investigate these relationships in men.

Methods:

Between 2006 and 2011, 928 men (aged 24-98 years) from the Geelong Osteoporosis Study completed a comprehensive questionnaire, clinical measurements and had BMD assessments at the forearm, spine, total hip and total body. Major depressive disorder (MDD) was identified using a structured clinical interview (SCID-I/NP). The cross-sectional associations between BMD and both MDD and antidepressant use were analyzed using multivariable linear regression.

Results:

Of the study population, 84 (9.1%) men had a single MDD episode, 50 (5.4%) had recurrent episodes and 65 (7.0%) were using antidepressants at the time of assessment. Following adjustments, recurrent MDD was associated with lower BMD at the forearm and total body (-6.5%, P=0.033 and -2.5%, P=0.033, respectively compared to men with no history of MDD), while single MDD episodes were associated with higher BMD at the total hip (+3.4%, P=0.030). Antidepressant use was associated with lower BMD only in lower-weight men (<75-110 kg depending on bone site).

Conclusions:

Both depression and use of antidepressants should be taken into account as possible risk factors for osteoporosis in men.     

Protective effect of polysaccharides from morinda officinalis on bone loss in ovariectomized rats

In order to examine the effect of polysaccharides from morinda officinalis (MOP) on bone quality of osteoporosis rats. The osteoporosis in rats was induced by ovariectomy, and MOP (100 or 300mg/kg) was orally administrated once daily. The animals were assessed 30 days after the operation for bone mineral density, serum cytokines level and mineral element concentration. MOP administration in rats resulted in an increase in bone mineral density and mineral element concentration, a decrease in serum cytokines level, which indicated that MOP administration may play an important role in the development of osteoporosis.     

Arsenite‐induced changes in hepatic protein abundance in cynomolgus monkeys (Macaca fascicularis)

Arsenic is an environmental pollutant, and its liver toxicity has long been recognized. The effect of arsenic on liver protein expression was analyzed using a proteomic approach in monkeys. Monkeys were orally administered sodium arsenite (SA) for 28 days. As shown by 2D‐PAGE in combination with MS, the expression levels of 16 proteins were quantitatively changed in SA‐treated monkey livers compared to control‐treated monkey livers. Specifically, the levels of two proteins, mortalin and tubulin beta chain, were increased, and 14 were decreased, including plastin‐3, cystathionine‐beta‐synthase, selenium‐binding protein 1, annexin A6, alpha‐enolase, phosphoenolpyruvate carboxykinase‐M, erlin‐2, and arginase‐1. In view of their functional roles, differential expression of these proteins may contribute to arsenic‐induced liver toxicity, including cell death and carcinogenesis. Among the 16 identified proteins, four were selected for validation by Western blot and immunohistochemistry. Additional Western blot analyses indicated arsenic‐induced dysregulation of oxidative stress related, genotoxicity‐related, and glucose metabolism related proteins in livers from SA‐treated animals. Many changes in the abundance of toxicity‐related proteins were also demonstrated in SA‐treated human hepatoma cells. These data on the arsenic‐induced regulation of proteins with critical roles may help elucidate the specific mechanisms underlying arsenic‐induced liver toxicity.     

The different correlations between obesity and osteoporosis after adjustment of static mechanical loading from weight and fat free mass

Objectives:To explore complex correlations between obesity (OB) and osteoporosis (OP) after adjustment of static mechanical loading from weight and fat free mass (FFM).Methods:A total of 3749 Chinese aged ≥65 years were selected from our ongoing cohort study. OB indices and bone mineral density (BMD) were measured for each subject. Linear regression analyses were performed to explore the correlations between OB indices and OP under three adjustment models (unadjusted, adjusted with weight and adjusted with FFM).Results:Under no adjustment, three general obesity indices (body mass index: BMI, fat mass: FM, and percentage FM: PFM) were positively associated with BMD at three skeletal sites (P<0.001) in the regression analyses. However, after the adjustment with weight, these associations were mostly significant but reverse i.e., negatively in direction. After adjustment with FFM, the three indices were still positively and significantly (P<0.001) associated with BMD but regression coefficients were smaller compared to the unadjusted associations. Similar associations were observed for central adiposity and lower limb adiposity indices.Conclusions:The combined relation of OB to OP due to the physiological factors secreted from adipose tissues and the static mechanical loading from FM is positive in direction.     

Association of vitamin D,BMD and knee osteoarthritis in postmenopausal women

Objectives:The aim of this study was to analyze the association of knee OA with bone mineral density (BMD) and vitamin D serum levels in postmenopausal women.Methods:A cross-sectional study including 240 postmenopausal women with knee OA was conducted. Demographic data were recorded along with balance and functionality scores. Knee OA severity was assessed by the radiological Kellgren & Lawrence scale. BMD and T-scores were calculated in hips and lumbar spine. Serum levels of vitamin D were also measured.Results:High BMI (p<0.005), high number of children (p=0.022) and family history of hip fracture (p=0.011) are significantly associated with knee OA severity. Lumbar spine OP is negatively associated with knee OA (p<0.005). A significant difference was detected between vitamin D deficiency and severe knee OA, adjusted for BMD [OR (95%CI); 3.1 (1.6-6.1), p=0.001]. BMD does not affect the relationship of vitamin D levels in relation to OA and vitamin D levels do not affect the relationship of BMD with OA.Conclusions:Low BMD has a protective role against knee OA while vitamin D deficiency contributes significantly to knee OA severity. However, the association between OA and OP is not affected by vitamin D deficiency and the association of OA and vitamin D serum levels is not affected by BMD.     

Suit therapy versus whole-body vibration on bone mineral density in children with spastic diplegia

Objectives:Osteoporosis because of physical inactivity is one of the major complications associated with neuromuscular disorders. The study aimed to compare using Suit therapy and whole-body vibration in addition to selected physical therapy program to improve Bone Mineral Density in children with cerebral palsy of spastic diplegia.Methods:Forty-six patients were classified randomly into two equal groups. Patients in the group (A) engaged in a selected physical therapy program, also besides, suit therapy training program while those in the group (B) received the same selected physical therapy program received by group (A) in addition to the whole-body vibration training program. The treatment programs were conducted three times per week for twelve successive weeks. Measurements obtained included bone mineral density at the lumbar spine as well as at the femoral neck. These measures were recorded pre- and post-treatment.Results:There was a significant improvement in favor of the whole-body Vibration group. Bone mineral density improved significantly at both the lumbar spine (P=.038) and the femoral neck (P=.005) in the WBV group as compared to the Suit therapy group.Conclusions:Whole-body vibration is effective in improving Bone Mineral Density rather than Suit therapy in children with cerebral palsy of spastic diplegia.     

Effects of thirty elements on bone metabolism

The human skeleton, made of 206 bones, plays vital roles including supporting the body, protecting organs, enabling movement, and storing minerals. Bones are made of organic structures, intimately connected with an inorganic matrix produced by bone cells. Many elements are ubiquitous in our environment, and many impact bone metabolism. Most elements have antagonistic actions depending on concentration. Indeed, some elements are essential, others are deleterious, and many can be both. Several pathways mediate effects of element deficiencies or excesses on bone metabolism. This paper aims to identify all elements that impact bone health and explore the mechanisms by which they act. To date, this is the first time that the effects of thirty minerals on bone metabolism have been summarized.     

Acute bone response to whole body vibration in healthy pre-pubertal boys

The skeleton responds to mechanical stimulation. We wished to ascertain the magnitude and speed of the growing skeleton’s response to a standardised form of mechanical stimulation, vibration. 36 prepubertal boys stood for 10 minutes in total on one of two vibrating platforms (high (>2 g) or low (<1 g) magnitude vibration) on either 1, 3 or 5 successive days (n=12 for each duration); 15 control subjects stood on an inactive platform. Blood samples were taken at intervals before and after vibration to measure bone formation (P1NP, osteocalcin) and resorption (CTx) markers as well as osteoprotegerin and sclerostin. There were no significant differences between platform and control groups in bone turnover markers immediately after vibration on days 1, 3 and 5. Combining platform groups, at day 8 P1NP increased by 25.1% (CI 12.3 to 38.0; paired t-test p=0.005) and bone resorption increased by 10.9% (CI 3.6 to 18.2; paired t-test p=0.009) compared to baseline. Osteocalcin, osteoprotogerin and sclerostin did not change significantly. The growing skeleton can respond quickly to vibration of either high or low magnitude. Further work is needed to determine the utility of such “stimulation-testing” in clinical practice.     

Alveolar bone response distal to applied orthodontic forces in ovariectomized rats

Objectives:The aim of this study was to investigate the effect of the application of orthodontic tooth forces on the alveolar bone distal to the loaded teeth, in ovariectomized female rats.Methods:Twenty-four eight-month-old Wistar rats were divided into one group ovariectomized at the age of six months and one control. An orthodontic appliance delivering a mesial traction force of 60 gr* was placed on the right maxillary 1^st molar of all animals for 14 days. Histology of the alveolar bone, of the adjacent and distal teeth to the loaded molar and the contralateral side, was performed following euthanasia.Results:In the non-ovariectomized rats, extensive resorption was noticed in the direction of the orthodontic movement in the 2^nd and 3^rd molar interdental space, whereas the respective contralateral interdental space did not show any remodeling activity. Ovariectomized rats displayed reduced osseous tissue in the interdental space of both sides. The alveolar bone in the interradicular area of the 2^nd loaded molar revealed frontal resorption, whereas, the alveolar interradicular bone of the contralateral 2^nd molar showed internal resorption.Conclusions:In conclusion, orthodontic forces applied to the dentoalveolar complex of ovariectomized rats affect bone remodeling, even in areas distal to the site of force application. This finding should be taken into account during orthodontic treatment of women during menopause.     

Use of a facemask to protect the intra-oral area in cynomolgus monkeys

A custom fiberglass facemask was designed for cynomolgus monkeys to protect an orthodontic appliance. The mask was constructed from impressions and models made of the animal's head. It prevented the fingers from entering the mouth to dislodge the intra-oral appliances. The facemask permitted normal physical activity, eating, and drinking.     

Proteome analysis for the identification of in vivo estrogen-regulated proteins in bone

Estrogen deficiency results in a reduced bone mass, which can be prevented by treatment with estrogens. This study used a proteomic approach for the first time to obtain a global perspective of estrogens' effects on whole-bone proteins. Bone proteome profiles were examined in three groups of mice: (1) sham-operated with normal ovarian functions, (2) ovariectomised and (3) ovariectomised with estrogen replacement therapy. Bone proteins extracted from the humerus were separated by 2-DE and visualised by CBB colloidal staining. Spot detection and quantification was done by image analysis. Differentially expressed proteins were identified by MS and database search, using peptide mass fingerprint and peptide sequence analysis. Differential expression analysis in the three experimental groups showed significant changes for 14 proteins. These included proteins related to bone metabolism, cytoskeleton components and energy metabolic pathways. Our data suggest that some proteins related to cytoskeleton and to energy pathways, such as tropomyosins, aconitase 2 and enolase beta, might be new molecular targets responsive to the effects of estrogen. Differentially expressed proteins identified in this model may offer a useful starting point for elucidating novel aspects of the pleiotropic effects of estrogens on bone.     

去卵巢大鼠血清和骨髓细胞碱性磷酸酶水平变化的动态观察

目的：动态观察去卵巢大鼠血清和骨髓细胞碱性磷酸酶（ ALP）水平的变化。方法将80只3月龄雌性SD大鼠按体重分层后随机分为基础组以及假手术和去卵巢3、6、12、24周组。分别在手术前（0）和手术后3、6、12、24周腹主动脉取血处死各组大鼠,分离血清,制备骨髓细胞甩片,用721分光光度计检测血清ALP水平的变化;用显微镜计数骨髓细胞甩片ALP阳性染色细胞的数目。结果在假手术组大鼠中,血清ALP水平在手术后3周显著上升并持续到手术后6周,但在手术后12周开始显著下降并持续到手术后24周;骨髓细胞ALP阳性染色细胞数目在手术后3周显著上升并持续到手术后12周,但在手术后24周却显著下降。在去卵巢组大鼠中,血清ALP水平在手术后3周显著上升,到手术后6周开始显著下降并一直持续到手术后24周;骨髓细胞ALP阳性染色细胞数目在手术后3周显著下降并持续到手术后24周。从手术后3周开始,去卵巢组大鼠血清ALP水平均显著高于假手术组大鼠,但骨髓细胞ALP阳性染色细胞数目均显著低于假手术组大鼠。结论假手术组大鼠血清和骨髓细胞ALP水平变化趋势基本相似,但去卵巢大鼠血清和骨髓细胞ALP水平变化趋势不同。     

Oral administration of phytocomponent p-hydroxycinnamic acid prevents bone loss in ovariectomized rats

The preventive effect of phytocomponent p-hydroxycinnamic acid (HCA) on ovariectomy (OVX)-induced bone loss was investigated. HCA (250 or 500 μg/100 g body weight) was orally administered once daily for 30 days to OVX rats. The analysis using a peripheral quantitative computed tomography (pQCT) showed that OVX caused bone loss in the femoral-metaphyseal tissues. This change was significantly restored after the administration of HCA (250 or 500 μg/100 g body weight) to OVX rats. Mineral content, mineral density, and polar strength strain index in the femoral-metaphyseal tissues were significantly decreased in OVX rats. These decreases were significantly restored after the administration of HCA (500 μg/100 g) to OVX rats. Moreover, OVX caused a significant decrease in calcium content or alkaline phosphatase activity in the femoral-diaphyseal and -metaphyseal tissues. These decreases were significantly restored after the administration of HCA (250 or 500 μg/100 g) to OVX rats. Deoxyribonucleic acid (DNA) content in the diaphyseal or metaphyseal tissues was significantly increased in OVX rats. These increases were significantly restored after oral administration of HCA (500 μg/100 g). This study demonstrates that HCA has preventive effects on OVX-induced bone loss of rats in vivo.     

青少年食蟹猴糖尿病模型的肝脏病理生理学研究

目的通过对胰岛素用量不足条件下链脲佐菌素诱导的青少年食蟹猴1型糖尿病模型肝脏病理生理学的研究,探讨长期高血糖所致青少年食蟹猴肝损伤特点及机制。方法通过静脉注射68 mg/kg的链脲佐菌素,诱导4只3岁的食蟹猴成为1型糖尿病模型,然后经长期的血糖监测和静脉糖耐量实验来评价该模型的可靠性及稳定性,造模4年后,对模型猴进行血生化、PAS染色、苏丹III染色及普通病理和超微病理等指标的检测,另外选取4只健康与模型猴年龄匹配的猴作为正常对照组,同时进行相应的检测。结果与正常对照组比较,糖尿病猴血清学检测指标中总胆汁酸、尿素氮、谷丙转氨酶、谷草转氨酶、胆碱酯酶、乳酸脱氢酶、总胆固醇、甘油三酯和低密度脂蛋白胆固醇明显升高。组织化学染色结果显示,与正常猴比较,糖尿病猴中央静脉区肝实质细胞肿胀,肝细胞PAS染色（糖原染色）加深,苏丹Ⅲ染色（脂肪染色）阳性细胞增多;电镜结果显示糖尿病猴肝细胞内胞质糖原颗粒增多;线粒体电子密度显著增高,结构不清;窦周隙内含有大量脂滴的肝星状细胞明显增多。结论在长期胰岛素用量不足血糖控制不理想的条件下,青少年食蟹猴1型糖尿病模型肝脏特异性的病理改变是肝糖原贮积和含有大量脂滴的肝星状细胞增生,这些病理改变与非酒精性脂肪肝病的病变特点存在显著不同,但其机制目前尚不清楚。     

Collagen overglycosylation: a biochemical feature that may contribute to bone quality

Skeletal ability to resist mechanical stress is determined by bone amount and quality, which relies on macro- and micro-architecture, turnover, bone matrix, and mineralisation; the role of collagen has not been clearly elucidated. Numerous post-translational steps are involved in collagen type I biosynthesis, including residue hydroxylation and glycosylation catalysed by enzymes that work until the protein folds forming the triple helix; therefore, folding rate regulates these processes. Overglycosylated hydroxylysines are poor substrates for epsilon-amino group deamination which initiates cross-link formation. Three clinical conditions associated with fractures may relate collagen overglycosylation with bone quality: (i) Osteogenesis Imperfecta, in which genetic mutations distort triple helix conformation and slow folding rate favouring overglycosylation; (ii) diabetes mellitus, with collagen overglycosylation by AGE accumulation; and, (iii) menopause, according to experimental studies demonstrating ovariectomy-related trabecular bone collagen overglycosylation preventable by 17beta-estradiol or tamoxifen. Specific actions on collagen of drugs used for bone protection should be explored in future studies.     

近交系MIJ和HFJ大鼠生化标记基因的测定

目的 观察MIJ和HFJ大鼠的基因纯合度和遗传稳定性.方法 MIJ大鼠7只,取自F22代基础群中3对种鼠和F22代雄性生殖缺陷鼠1只.HFJ大鼠6只,取自HFJ大鼠F25代基础群中的3对种鼠.按照中华人民共和国国家标准GB/T14927.1-2001实验动物近交系小鼠、大鼠生化标记检测方法测定.结果　MIJ和HFJ近交...