Irisin is a polypeptide hormone derived from the proteolytic cleavage of fibronectin-type III domain- containing 5 (FNDC5) protein. Once released to circulation upon exercise or cold exposure, irisin stimulates brow...Irisin is a polypeptide hormone derived from the proteolytic cleavage of fibronectin-type III domain- containing 5 (FNDC5) protein. Once released to circulation upon exercise or cold exposure, irisin stimulates browning of white adipose tissue (WAT) and uncoupling protein I (UCP1) expression, leading to an increase in total body energy expenditure by augmented UCPl-mediated thermogenesis. It is currently unknown whether irisin is secreted by bone upon exercise or whether it regulates bone metabolism in vivo. In this study, we found that 2 weeks of voluntary wheel-running exercise induced high levels of FNDC5 messenger RNA as well as FNDC5/irisin protein expression in murine bone tissues. Increased immunoreactivity due to exercise-induced FNDC5/irisin expression was detected in different regions of exercised femoral bones, including growth plate, trabecular bone, cortical bone, articular cartilage, and bone-tendon interface. Exercise also increased expression of osteogenic markers in bone and that of UCP1 in WAT, and led to bodyweight loss. Irisin intraperitoneal (IP) administration resulted in increased trabecular and cortical bone thickness and osteoblasts numbers, and concurrently induced UCP1 expression in subcutaneous WAT. Lentiviral FNDC5 IP administration increased cortical bone thickness. In vitro studies in bone cells revealed irisin increases osteoblastogenesis and mineralization, and inhibits receptor activator of nuclear factor-kB ligand (RANKL)- induced osteoclastogenesis. Taken together, our findings show that voluntary exercise increases irisin production in bone, and that an increase in circulating irisin levels enhances osteogenesis in mice.展开更多
Ankylosing spondylitis(AS)has a very high disability rate.How to effectively inhibit the formation of new bones has become a difficult point in clinical treatment.In recent years,research has shown that different trea...Ankylosing spondylitis(AS)has a very high disability rate.How to effectively inhibit the formation of new bones has become a difficult point in clinical treatment.In recent years,research has shown that different treatment plans can have an impact on inhibiting new bone formation.In this paper,the different effects of new bone formation in the treatment of AS with traditional Chinese and Western medicine are systematically listed.展开更多
Daily 20-mg and once-weekly 56.5-mg teriparatide(parathyroid hormone 1–34) treatment regimens increase bone mineral density(BMD) and prevent fractures, but changes in bone turnover markers differ between the two ...Daily 20-mg and once-weekly 56.5-mg teriparatide(parathyroid hormone 1–34) treatment regimens increase bone mineral density(BMD) and prevent fractures, but changes in bone turnover markers differ between the two regimens. The aim of the present study was to explain changes in bone turnover markers using once-weekly teriparatide with a simulation model. Temporary increases in bone formation markers and subsequent decreases were observed during once-weekly teriparatide treatment for 72 weeks. These observations support the hypothesis that repeated weekly teriparatide administration stimulates bone remodeling, replacing old bone with new bone and leading to a reduction in the active remodeling surface. A simulation model was developed based on the iterative remodeling cycle that occurs on residual old bone. An increase in bone formation and a subsequent decrease were observed in the preliminary simulation. For each fitted time point, the predicted value was compared to the absolute values of the bone formation and resorption markers and lumbar BMD. The simulation model strongly matched actual changes in bone turnover markers and BMD. This simulation model indicates increased bone formation marker levels in the early stage and a subsequent decrease. It is therefore concluded that remodeling-based bone formation persisted during the entire treatment period with once-weekly teriparatide.展开更多
A new type of machinable bioactive glass-ceramics for bone substitution has been developed in the glass system SiO_2-MgO-K_2O-F^--CaO-P_2O_5, which contains Mg- muscovite [K_2Mg_5 (Si_8O_(20)) F_4] and fluorapatite as...A new type of machinable bioactive glass-ceramics for bone substitution has been developed in the glass system SiO_2-MgO-K_2O-F^--CaO-P_2O_5, which contains Mg- muscovite [K_2Mg_5 (Si_8O_(20)) F_4] and fluorapatite as the two main crystal phases. The phase separation and the crystallization of the glass have been studied. A series of tests have showed that the material is good at mechanical property and bioactivity. Espe- cially, by analysing the structure of the interface layer between the material and the bone of animal with scanning electron microscope, electron probe, etc., it has been found that the new bone hydroxya- patite is formed on the surface of the material so that the material is connected firmly with the bone.展开更多
目的定量分析碱性磷酸酶(ALP)和骨钙素(OC)在成骨过程中不同时期的表达,从而了解骨形成的进程,为正畸治疗提供一些理论依据。方法用雄性C57BL/6J小鼠建立骨折模型,并从新生的C57BL/6J小鼠头盖骨提取初级成骨细胞,采用苏木精-伊红染色法,...目的定量分析碱性磷酸酶(ALP)和骨钙素(OC)在成骨过程中不同时期的表达,从而了解骨形成的进程,为正畸治疗提供一些理论依据。方法用雄性C57BL/6J小鼠建立骨折模型,并从新生的C57BL/6J小鼠头盖骨提取初级成骨细胞,采用苏木精-伊红染色法,Northern blot法及Real Time PCR(定量PCR)法对骨形成过程进行体内体外形态学及ALP、OC表达的分析。结果骨折后ALP和OC的表达逐渐增加,第10天达高峰,其后开始下降;体外初级成骨细胞培养发现ALP和OC的表达于第14天达高峰,随后开始下降,但至21 d时,两者仍维持在相当高的水平。结论ALP和OC在新骨形成过程中并不是无止境的增加,其表达随成骨细胞的不断分化而逐渐增加并随成熟骨细胞的增多而下降。展开更多
基金supported by a R01DE21464 through the National Institutes of Healthan Innovation in Oral Care Award through International Association for Dental Research and Glaxo Smith Kline Consumer Healthcare+2 种基金an Award through International Team of Implantology to JCby GZUCM Science Fund for Creative Research Groups(2016KYTD10)GZUCM Torch Program(A1-AFD015142Z08)to JZ
文摘Irisin is a polypeptide hormone derived from the proteolytic cleavage of fibronectin-type III domain- containing 5 (FNDC5) protein. Once released to circulation upon exercise or cold exposure, irisin stimulates browning of white adipose tissue (WAT) and uncoupling protein I (UCP1) expression, leading to an increase in total body energy expenditure by augmented UCPl-mediated thermogenesis. It is currently unknown whether irisin is secreted by bone upon exercise or whether it regulates bone metabolism in vivo. In this study, we found that 2 weeks of voluntary wheel-running exercise induced high levels of FNDC5 messenger RNA as well as FNDC5/irisin protein expression in murine bone tissues. Increased immunoreactivity due to exercise-induced FNDC5/irisin expression was detected in different regions of exercised femoral bones, including growth plate, trabecular bone, cortical bone, articular cartilage, and bone-tendon interface. Exercise also increased expression of osteogenic markers in bone and that of UCP1 in WAT, and led to bodyweight loss. Irisin intraperitoneal (IP) administration resulted in increased trabecular and cortical bone thickness and osteoblasts numbers, and concurrently induced UCP1 expression in subcutaneous WAT. Lentiviral FNDC5 IP administration increased cortical bone thickness. In vitro studies in bone cells revealed irisin increases osteoblastogenesis and mineralization, and inhibits receptor activator of nuclear factor-kB ligand (RANKL)- induced osteoclastogenesis. Taken together, our findings show that voluntary exercise increases irisin production in bone, and that an increase in circulating irisin levels enhances osteogenesis in mice.
基金Supported by the National Natural Science Foundation of China(82205105).
文摘Ankylosing spondylitis(AS)has a very high disability rate.How to effectively inhibit the formation of new bones has become a difficult point in clinical treatment.In recent years,research has shown that different treatment plans can have an impact on inhibiting new bone formation.In this paper,the different effects of new bone formation in the treatment of AS with traditional Chinese and Western medicine are systematically listed.
文摘Daily 20-mg and once-weekly 56.5-mg teriparatide(parathyroid hormone 1–34) treatment regimens increase bone mineral density(BMD) and prevent fractures, but changes in bone turnover markers differ between the two regimens. The aim of the present study was to explain changes in bone turnover markers using once-weekly teriparatide with a simulation model. Temporary increases in bone formation markers and subsequent decreases were observed during once-weekly teriparatide treatment for 72 weeks. These observations support the hypothesis that repeated weekly teriparatide administration stimulates bone remodeling, replacing old bone with new bone and leading to a reduction in the active remodeling surface. A simulation model was developed based on the iterative remodeling cycle that occurs on residual old bone. An increase in bone formation and a subsequent decrease were observed in the preliminary simulation. For each fitted time point, the predicted value was compared to the absolute values of the bone formation and resorption markers and lumbar BMD. The simulation model strongly matched actual changes in bone turnover markers and BMD. This simulation model indicates increased bone formation marker levels in the early stage and a subsequent decrease. It is therefore concluded that remodeling-based bone formation persisted during the entire treatment period with once-weekly teriparatide.
文摘A new type of machinable bioactive glass-ceramics for bone substitution has been developed in the glass system SiO_2-MgO-K_2O-F^--CaO-P_2O_5, which contains Mg- muscovite [K_2Mg_5 (Si_8O_(20)) F_4] and fluorapatite as the two main crystal phases. The phase separation and the crystallization of the glass have been studied. A series of tests have showed that the material is good at mechanical property and bioactivity. Espe- cially, by analysing the structure of the interface layer between the material and the bone of animal with scanning electron microscope, electron probe, etc., it has been found that the new bone hydroxya- patite is formed on the surface of the material so that the material is connected firmly with the bone.
文摘目的定量分析碱性磷酸酶(ALP)和骨钙素(OC)在成骨过程中不同时期的表达,从而了解骨形成的进程,为正畸治疗提供一些理论依据。方法用雄性C57BL/6J小鼠建立骨折模型,并从新生的C57BL/6J小鼠头盖骨提取初级成骨细胞,采用苏木精-伊红染色法,Northern blot法及Real Time PCR(定量PCR)法对骨形成过程进行体内体外形态学及ALP、OC表达的分析。结果骨折后ALP和OC的表达逐渐增加,第10天达高峰,其后开始下降;体外初级成骨细胞培养发现ALP和OC的表达于第14天达高峰,随后开始下降,但至21 d时,两者仍维持在相当高的水平。结论ALP和OC在新骨形成过程中并不是无止境的增加,其表达随成骨细胞的不断分化而逐渐增加并随成熟骨细胞的增多而下降。