Enhanced osteoclastogenesis and osteoclast activity contribute to the development of osteoporosis,which is characterized by increased bone resorption and inadequate bone formation.As novel antiosteoporotic therapeutic...Enhanced osteoclastogenesis and osteoclast activity contribute to the development of osteoporosis,which is characterized by increased bone resorption and inadequate bone formation.As novel antiosteoporotic therapeutics are needed,understanding the genetic regulation of human osteoclastogenesis could help identify potential treatment targets.This study aimed to provide an overview of transcriptional reprogramming during human osteoclast differentiation.Osteoclasts were differentiated from CD14+monocytes from eight female donors.RNA sequencing during differentiation revealed 8980 differentially expressed genes grouped into eight temporal patterns conserved across donors.These patterns revealed distinct molecular functions associated with postmenopausal osteoporosis susceptibility genes based on RNA from iliac crest biopsies and bone mineral density SNPs.Network analyses revealed mutual dependencies between temporal expression patterns and provided insight into subtype-specific transcriptional networks.The donor-specific expression patterns revealed genes at the monocyte stage,such as filamin B(FLNB)and oxidized low-density lipoprotein receptor 1(OLR1,encoding LOX-1),that are predictive of the resorptive activity of mature osteoclasts.The expression of differentially expressed G-protein coupled receptors was strong during osteoclast differentiation,and these receptors are associated with bone mineral density SNPs,suggesting that they play a pivotal role in osteoclast differentiation and activity.The regulatory effects of three differentially expressed G-protein coupled receptors were exemplified by in vitro pharmacological modulation of complement 5 A receptor 1(C5AR1),somatostatin receptor 2(SSTR2),and free fatty acid receptor 4(FFAR4/GPR120).Activating C5AR1 enhanced osteoclast formation,while activating SSTR2 decreased the resorptive activity of mature osteoclasts,and activating FFAR4 decreased both the number and resorptive activity of mature osteoclasts.In conclusion,we report the occurrence of transcriptional reprogramming during human osteoclast differentiation and identified SSTR2 and FFAR4 as antiresorptive G-protein coupled receptors and FLNB and LOX-1 as potential molecular markers of osteoclast activity.These data can help future investigations identify molecular regulators of osteoclast differentiation and activity and provide the basis for novel antiosteoporotic targets.展开更多
Acceleration of tooth movement during orthodontic treatment is challenging, with osteoclast-mediated bone resorption on the compressive side being the rate-limiting step. Recent studies have demonstrated that mechanor...Acceleration of tooth movement during orthodontic treatment is challenging, with osteoclast-mediated bone resorption on the compressive side being the rate-limiting step. Recent studies have demonstrated that mechanoreceptors on the surface of monocytes/macrophages, especially adhesion G protein-coupled receptors (aGPCRs), play important roles in force sensing.However, its role in the regulation of osteoclast differentiation remains unclear. Herein, through single-cell analysis, we revealed that CD97, a novel mechanosensitive aGPCR, was expressed in macrophages. Compression upregulated CD97 expression and inhibited osteoclast differentiation;while knockdown of CD97 partially rescued osteoclast differentiation. It suggests that CD97 may be an important mechanosensitive receptor during osteoclast differentiation. RNA sequencing analysis showed that the Rap1a/ERK signalling pathway mediates the effects of CD97 on osteoclast differentiation under compression. Consistently, we clarified that administration of the Rap1a inhibitor GGTI298 increased osteoclast activity, thereby accelerating tooth movement. In conclusion,our results indicate that CD97 suppresses osteoclast differentiation through the Rap1a/ERK signalling pathway under orthodontic compressive force.展开更多
Giant cell tumors of the pancreas come in three varieties-osteoclastic,pleomorphic,and mixed histology.These tumors have distinctive endoscopic,clinical,and cytological features.Giant cell tumors have a controversial ...Giant cell tumors of the pancreas come in three varieties-osteoclastic,pleomorphic,and mixed histology.These tumors have distinctive endoscopic,clinical,and cytological features.Giant cell tumors have a controversial histogenesis,with some authors favoring an epithelial origin and others favoring a mesenchymal origin.The true origin of these lesions remains unclear at this time.These are also very rare tumors but proper identification and differentiation from more common pancreatic adenocarcinoma is important.The risk factors of these tumors and the prognosis may be different from those associated with standard pancreatic adenocarcinoma.Recognition of these differences can significantly affect patient care.These lesions have a unique appearance when imaged with endoscopic ultrasound(EUS),and these lesions can be diagnosed via EUS guided Fine Needle Aspiration(FNA).This manuscript will review the endoscopic,clinical,and pathologic features of these tumors.展开更多
Toll-like receptors(TLRs)play pivotal roles in inflammation and provide important links between the immune and skeletal systems.Although the activation of TLRs may affect osteoclast differentiation and bone metabolism...Toll-like receptors(TLRs)play pivotal roles in inflammation and provide important links between the immune and skeletal systems.Although the activation of TLRs may affect osteoclast differentiation and bone metabolism,whether and how TLRs are required for normal bone remodeling remains to be fully explored.In the current study,we show for the first time that TLR9^(-/-)mice exhibit a low bone mass and low-grade systemic chronic inflammation,which is characterized by the expansion of CD4^(+)T cells and increased levels of inflammatory cytokines,including TNFα,RANKL,and IL1β.The increased levels of these cytokines significantly promote osteoclastogenesis and induce bone loss.Importantly,TLR9 deletion alters the gut microbiota,and this dysbiosis is the basis of the systemic inflammation and bone loss observed in TLR9^(-/-)mice.Furthermore,through single-cell RNA sequencing,we identified myeloid-biased hematopoiesis in the bone marrow of TLR9^(-/-)mice and determined that the increase in myelopoiesis,likely caused by the adaptation of hematopoietic stem cells to systemic inflammation,also contributes to inflammation-induced osteoclastogenesis and subsequent bone loss in TLR9^(-/-)mice.Thus,our study provides novel evidence that TLR9 signaling connects the gut microbiota,immune system,and bone and is critical in maintaining the homeostasis of inflammation,hematopoiesis,and bone metabolism under normal conditions.展开更多
Rheumatoid arthritis(RA)and periodontitis are chronic inflammatory diseases leading to increased bone resorption.Preventing this inflammatory bone resorption is a major health challenge.Both diseases share immunopatho...Rheumatoid arthritis(RA)and periodontitis are chronic inflammatory diseases leading to increased bone resorption.Preventing this inflammatory bone resorption is a major health challenge.Both diseases share immunopathogenic similarities and a common inflammatory environment.The autoimmune response or periodontal infection stimulates certain immune actors,leading in both cases to chronic inflammation that perpetuates bone resorption.Moreover,RA and periodontitis have a strong epidemiological association that could be explained by periodontal microbial dysbiosis.This dysbiosis is believed to be involved in the initiation of RA via three mechanisms.(i)The dissemination of periodontal pathogens triggers systemic inflammation.(ii)Periodontal pathogens can induce the generation of citrullinated neoepitopes,leading to the generation of anti-citrullinated peptide autoantibodies.(iii)Intracellular danger-associated molecular patterns accelerate local and systemic inflammation.Therefore,periodontal dysbiosis could promote or sustain bone resorption in distant inflamed joints.Interestingly,in inflammatory conditions,the existence of osteoclasts distinct from“classical osteoclasts”has recently been reported.They have proinflammatory origins and functions.Several populations of osteoclast precursors have been described in RA,such as classical monocytes,a dendritic cell subtype,and arthritis-associated osteoclastogenic macrophages.The aim of this review is to synthesize knowledge on osteoclasts and their precursors in inflammatory conditions,especially in RA and periodontitis.Special attention will be given to recent data related to RA that could be of potential value in periodontitis due to the immunopathogenic similarities between the two diseases.Improving our understanding of these pathogenic mechanisms should lead to the identification of new therapeutic targets involved in the pathological inflammatory bone resorption associated with these diseases.展开更多
Osteoclasts are primary bone-resorbing cells,and receptor-activated NF-k B ligand(RANKL)stimulation is the key driver of osteoclast differentiation.During late-stage differentiation,osteoclasts become multinucleated a...Osteoclasts are primary bone-resorbing cells,and receptor-activated NF-k B ligand(RANKL)stimulation is the key driver of osteoclast differentiation.During late-stage differentiation,osteoclasts become multinucleated and enlarged(so-called“maturation”),suggesting their need to adapt to changing metabolic demands and a substantial increase in size.Here,we demonstrate that immunoglobulin superfamily 11(Ig SF11),which is required for osteoclast differentiation through an association with the postsynaptic scaffolding protein PSD-95,regulates osteoclast differentiation by controlling the activity of pyruvate kinase M isoform2(PKM2).By using a system that directly induces the activation of Ig SF11 in a controlled manner,we identified PKM2 as a major Ig SF11-induced tyrosine-phosphorylated protein.Ig SF11 activates multiple Src family tyrosine kinases(SFKs),including c-Src,Fyn,and Hc K,which phosphorylate PKM2 and thereby inhibit PKM2 activity.Consistently,Ig SF11-deficient cells show higher PKM2activity and defective osteoclast differentiation.Furthermore,inhibiting PKM2 activities with the specific inhibitor Shikonin rescues the impaired osteoclast differentiation in Ig SF11-deficient cells,and activating PKM2 with the specific activator TEPP46 suppresses osteoclast differentiation in wild-type cells.Moreover,PKM2 activation further suppresses osteoclastic bone loss without affecting bone formation in vivo.Taken together,these results show that Ig SF11 controls osteoclast differentiation through PKM2 activity,which is a metabolic switch necessary for optimal osteoclast maturation.展开更多
Glycans,either alone or in complex with glycan-binding proteins,are essential structures that can regulate cell biology by mediating protein stability or receptor dimerization under physiological and pathological cond...Glycans,either alone or in complex with glycan-binding proteins,are essential structures that can regulate cell biology by mediating protein stability or receptor dimerization under physiological and pathological conditions.Certain glycans are ligands for lectins,which are carbohydrate-specific receptors.Bone is a complex tissue that provides mechanical support for muscles and joints,and the regulation of bone mass in mammals is governed by complex interplay between bone-forming cells,called osteoblasts,and bone-resorbing cells,called osteoclasts.Bone erosion occurs when bone resorption notably exceeds bone formation.Osteoclasts may be activated during cancer,leading to a range of symptoms,including bone pain,fracture,and spinal cord compression.Our understanding of the role of protein glycosylation in cells and tissues involved in osteoclastogenesis suggests that glycosylation-based treatments can be used in the management of diseases.The aims of this review are to clarify the process of bone resorption and investigate the signaling pathways mediated by glycosylation and their roles in osteoclast biology.Moreover,we aim to outline how the lessons learned about these approaches are paving the way for future glycobiology-focused therapeutics.展开更多
Background:Wear particles-induced osteolysis is a major long-term complication after total joint arthroplasty.Up to now,there is no effective treatment for wear particles-induced osteolysis except for the revision sur...Background:Wear particles-induced osteolysis is a major long-term complication after total joint arthroplasty.Up to now,there is no effective treatment for wear particles-induced osteolysis except for the revision surgery,which is a heavy psychological and economic burden to patients.A metabolite of gut microbiota,short chain fatty acids(SCFAs),has been reported to be beneficial for many chronic inflammatory diseases.This study aimed to investigate the therapeutic effect of SCFAs on osteolysis.Methods:A model of inflammatory osteolysis was established by applying CoCrMo alloy particles to mouse calvarium.After two weeks of intervention,the anti-inflammatory effects of SCFAs on wear particle-induced osteolysis were evaluated by micro-CT analysis and immunohistochemistry staining.In vitro study,lipopolysaccharide(LPS)primed bone marrow-derived macrophages(BMDMs)and Tohoku hospital pediatrics-1(THP-1)macrophages were stimulated with CoCrMo particles to activate inflammasome in the presence of acetate(C2),propionate(C3),and butyrate(C4).Western blotting,enzyme-linked immunosorbent assay,and immunofluorescence were used to detect the activation of NLRP3 inflammasome.The effects of SCFAs on osteoclasts were evaluate by qRT-PCR,Western blotting,immunofluorescence,and tartrate-resistant acid phosphatase(TRAP)staining.Additionally,histone deacetylase(HDAC)inhibitors,agonists of GPR41,GPR43,and GPR109A were applied to confirm the underlying mechanism of SCFAs on the inflammasome activation of macrophages and osteoclastogenesis.Results:C3 and C4 but not C2 could alleviate wear particles-induced osteolysis with fewer bone erosion pits(P<0.001),higher level of bone volume to tissue volume(BV/TV,P<0.001),bone mineral density(BMD,P<0.001),and a lower total porosity(P<0.001).C3 and C4 prevented CoCrMo alloy particles-induced ASC speck formation and nucleationinduced oligomerization,suppressing the cleavage of caspase-1(P<0.05)and IL-1β(P<0.05)stimulated by CoCrMo alloy particles.C3 and C4 also inhibited the generation of gasdermin D-N-terminal fragment(GSDMD-NT)to regulate pyroptosis.Besides,C3 and C4 have a negative impact on osteoclast differentiation(P<0.05)and its function(P<0.05),affecting the podosome arrangement and morphologically normal podosome belts formation.Conclusions:Our work showed that C3 and C4 are qualified candidates for the treatment of wear particle-induced osteolysis.展开更多
Objective:To investigate whether acupotomy could inhibit subchondral bone remodeling in knee osteoarthritis(KOA)rabbits by regulating the activity of osteoblasts and osteoclasts.Methods:KOA rabbits were prepared by im...Objective:To investigate whether acupotomy could inhibit subchondral bone remodeling in knee osteoarthritis(KOA)rabbits by regulating the activity of osteoblasts and osteoclasts.Methods:KOA rabbits were prepared by immobilization for 6 and 9 weeks by Videman method.Nine groups of rabbits(control,6 weeks and 9 weeks model,6 weeks and 9 weeks acupotomy,6 weeks and 9 weeks electroacupuncture,and 6 weeks and 9 weeks drug groups)received acupotomy,electroacupuncture and risedronate sodium intervention,respectively,for 3 weeks.Results:Acupotomy can inhibit the activity of osteoclasts and osteoblasts in subchondral bone by reducing the proteins expression of cathepsin K(CK)and tartrate-resistant acid phosphatase(TRAP)and decreasing the proteins expression of osteocalcin(OCN)and alkaline phosphatase(ALP),to intercept the abnormal bone resorption and bone formation of subchondral bone in 6-week and 9-week immobilization-induced KOA rabbits.Conclusion:These findings indicated that acupotomy may be more advantageous than risedronate sodium intervention in modulating subchondral bone remodeling in KOA rabbits,especially in 9-week immobilization-induced KOA rabbits.展开更多
BACKGROUND Invasive breast carcinoma with osteoclast-like stromal giant cells(OGCs) is an extremely rare morphology of breast carcinomas.To the best of our knowledge,the most recent case report describing this rare pa...BACKGROUND Invasive breast carcinoma with osteoclast-like stromal giant cells(OGCs) is an extremely rare morphology of breast carcinomas.To the best of our knowledge,the most recent case report describing this rare pathology was published six years ago.The mechanism controlling the development of this unique histological formation is still unknown.Further,the prognosis of patients with OGC involvement is also controversial.CASE SUMMARY We report the case of a 48-year-old woman,who presented to the outpatient department with a palpable,growing,painless mass in her left breast for about one year.Sonography and mammography revealed a 26.5 mm ×18.8 mm asymmetric,lobular mass with circumscribed margin and the Breast Imaging Reporting and Data System was category 4C.Sono-guided aspiration biopsy revealed invasive ductal carcinoma.The patient underwent breast conserving surgery and was diagnosed with invasive breast carcinoma with OGCs,grade Ⅱ,with intermediate grade of ductal carcinoma in situ(ER:80%,3+,PR:80%,3+,HER-2:negative,Ki 67:30%).Adjuvant chemotherapy and post-operation radiotherapy were initiated thereafter.CONCLUSION As a rare morphology of breast cancer,breast carcinoma with OGC occurs most often in relatively young women,has less lymph node involvement,and its occurrence is not racedependent.展开更多
Bone sialoprotein(BSP)is an important non-collagen extracellular matrix protein(EMC)that promotes bone formation and induces bone resorption.BSP is secreted by odontoblasts,it plays an important role in cementum,alveo...Bone sialoprotein(BSP)is an important non-collagen extracellular matrix protein(EMC)that promotes bone formation and induces bone resorption.BSP is secreted by odontoblasts,it plays an important role in cementum,alveolar bone formation and mineralization,and periodontal function.Bone resorption is controlled by a complex molecular network,and BSP can promote osteoclast differentiation and bone resorption.It is also associated with the metastasis of a range of malignancies.Osteoclasts(OC)are thought to be the only cells involved in bone resorption and play an important role in bone formation and late developmental remodeling.Osteoporosis and periodontal disease are caused by excessive bone resorption.This article will summarize the osteoclasts differentiation,the biological function of bone resorption,and explore the progress of the prevention and treatment of the related bone resorption diseases such as osteoporosis and periodontal disease through the regulation of osteoclasts.展开更多
Objective:To investigate whether miR-483-5p regulates osteoclast generation by targeting Timp2.miR-483-5p can promote osteoclast differentiation and bone destruction.Methods:Target genes of miR-483-5p were predicted b...Objective:To investigate whether miR-483-5p regulates osteoclast generation by targeting Timp2.miR-483-5p can promote osteoclast differentiation and bone destruction.Methods:Target genes of miR-483-5p were predicted by miRNAs target gene prediction software TargetScan8.0,and wild type and mutant 3'UTR plasmids were constructed.Dual luciferase reporter genes were used to verify whether target genes had a targeted regulatory relationship with miR-483-5p.Western blotting was used to detect the corresponding changes in the expression level of target protein after adjusting the level of miR-483-5p in cells.Cells were transfected or infected with target gene siRNA or target protein lentivirus,and TRAP staining and q-PCR assays were performed.In addition,for osteoclast induction experiment,RAW264.7 cells were co-transfected with ago-miR-483-5p and target protein-overexpressed lentiviruses q-PCR and TRAP staining were performed respectively.Results:Bioinformatics software was used to predict the target gene of miR-483-5p,and the Timp2 gene was found to regulate osteoclasts,and the dual luciferase reporter detection system found that miR-483-5p could be associated with the 3-UTR of the predicted target gene Timp2 gene.There are complementary loci and targeted regulatory relationship between them.Subsequently,we upregulated miR-483-5p in RAW264.7 cells to reduce the expression of Timp2.Compared with the normal group,the number of osteoclasts and the expression of osteoclast-specific genes increased significantly after the induction of Timp2 in knockdown cells.After co-transfection of target gene and miR-483-5p into cells,the number of osteoclasts and the expression of specific genes decreased significantly compared with the normal group.Conclusion:Timp2 is a downstream target gene of miR-483-5p and is involved in and inhibits osteoclast generation.展开更多
目的探讨免疫调节分子IL-33对绝经后骨质疏松症(postmenopausal osteoporosis,PMOP)模型鼠RANKL/c-Fos/NFATc1信号轴的调控作用及藤黄健骨胶囊(Tenghuang Jiangu capsule,TJC)的干预机制。方法构建PMOP大鼠模型,设置假手术组、PMOP模型...目的探讨免疫调节分子IL-33对绝经后骨质疏松症(postmenopausal osteoporosis,PMOP)模型鼠RANKL/c-Fos/NFATc1信号轴的调控作用及藤黄健骨胶囊(Tenghuang Jiangu capsule,TJC)的干预机制。方法构建PMOP大鼠模型,设置假手术组、PMOP模型组、阳性对照组(0.09 mg/kg)和TJC高、中、低剂量组(0.36、0.18、0.09 g/kg),灌胃给药,每天1次,持续8周。从大鼠末次给药后体质量、骨密度(bone mineral density,BMD)及股骨组织微结构等方面评价TJC的疗效;通过ELISA分析TJC对大鼠血清免疫调节因子IL-33、IL-1、IL-31变化;运用qPCR和Western blotting分析TJC对大鼠股骨OPG、RANKL、RANK、c-Fos、NFATc1表达量的影响。结果与假手术组相比,PMOP模型组大鼠的体质量、骨髓脂肪组织相对面积(relative area of bone marrow adipose tissue,BMAT),IL-1、IL-31变化,RANKL、RANK、c-Fos、NFATc1的表达均出现了明显升高的趋势,而BMD、IL-33变化、OPG的表达则出现了明显下降的趋势(P<0.01);与PMOP模型组相比,TJC高剂量组大鼠体质量出现显著下降趋势、IL-33变化出现显著升高趋势(P<0.01),TJC中、高剂量组大鼠BMAT、RANK的表达出现显著下降趋势、OPG的表达出现显著升高趋势(P<0.05或P<0.01),TJC各剂量组大鼠IL-1、IL-31变化,RANKL、c-Fos、NFATc1出现显著降低趋势,BMD出现显著增加趋势(P<0.05或P<0.01)。结论TJC能够提高PMOP大鼠免疫调控分子IL-33含量,抑制免疫调控分子IL-1、IL-31含量和破骨细胞分化标志分子NFATc1的表达,其机制可能与RANKL/c-Fos/NFATc1抑制骨代谢通路密切相关。展开更多
基金funded by grants from the Novo Nordisk Foundation (NNF18OC0052699) (M.S.H.) and NNF18OC0055047 (M.F.)the Region of Southern Denmark (ref: 18/17553 (M.S.H.))+3 种基金Odense University Hospital (ref: A3147) (M.F.)a faculty fellowship from the University of Southern Denmark (K.M.), the Lundbeck Foundation (ref: R335-2019-2195) (K.M.and A.R.)an Academy of Medical Sciences Springboard Award supported by the British Heart Foundation, Diabetes UK, the Global Challenges Research Fund, the Government Department of Business, Energy and Industrial Strategy and the Wellcome Trust (ref: SBF004 | 1034, C.M.G)a Sir Henry Dale Fellowship jointly funded by the Wellcome Trust and the Royal Society (Grant Number 224155/Z/21/Z to C.M.G.).
文摘Enhanced osteoclastogenesis and osteoclast activity contribute to the development of osteoporosis,which is characterized by increased bone resorption and inadequate bone formation.As novel antiosteoporotic therapeutics are needed,understanding the genetic regulation of human osteoclastogenesis could help identify potential treatment targets.This study aimed to provide an overview of transcriptional reprogramming during human osteoclast differentiation.Osteoclasts were differentiated from CD14+monocytes from eight female donors.RNA sequencing during differentiation revealed 8980 differentially expressed genes grouped into eight temporal patterns conserved across donors.These patterns revealed distinct molecular functions associated with postmenopausal osteoporosis susceptibility genes based on RNA from iliac crest biopsies and bone mineral density SNPs.Network analyses revealed mutual dependencies between temporal expression patterns and provided insight into subtype-specific transcriptional networks.The donor-specific expression patterns revealed genes at the monocyte stage,such as filamin B(FLNB)and oxidized low-density lipoprotein receptor 1(OLR1,encoding LOX-1),that are predictive of the resorptive activity of mature osteoclasts.The expression of differentially expressed G-protein coupled receptors was strong during osteoclast differentiation,and these receptors are associated with bone mineral density SNPs,suggesting that they play a pivotal role in osteoclast differentiation and activity.The regulatory effects of three differentially expressed G-protein coupled receptors were exemplified by in vitro pharmacological modulation of complement 5 A receptor 1(C5AR1),somatostatin receptor 2(SSTR2),and free fatty acid receptor 4(FFAR4/GPR120).Activating C5AR1 enhanced osteoclast formation,while activating SSTR2 decreased the resorptive activity of mature osteoclasts,and activating FFAR4 decreased both the number and resorptive activity of mature osteoclasts.In conclusion,we report the occurrence of transcriptional reprogramming during human osteoclast differentiation and identified SSTR2 and FFAR4 as antiresorptive G-protein coupled receptors and FLNB and LOX-1 as potential molecular markers of osteoclast activity.These data can help future investigations identify molecular regulators of osteoclast differentiation and activity and provide the basis for novel antiosteoporotic targets.
基金supported by the Natural Science Foundation of Hebei Province (H2020206226)Hebei Province Science and Technology Support Program (18277756D)+1 种基金the Science and Technology Research Project of Hebei Higher Education Institutions (ZD2022010)High-level Talent Funding Project of Hebei (C20231141) to W.W。
文摘Acceleration of tooth movement during orthodontic treatment is challenging, with osteoclast-mediated bone resorption on the compressive side being the rate-limiting step. Recent studies have demonstrated that mechanoreceptors on the surface of monocytes/macrophages, especially adhesion G protein-coupled receptors (aGPCRs), play important roles in force sensing.However, its role in the regulation of osteoclast differentiation remains unclear. Herein, through single-cell analysis, we revealed that CD97, a novel mechanosensitive aGPCR, was expressed in macrophages. Compression upregulated CD97 expression and inhibited osteoclast differentiation;while knockdown of CD97 partially rescued osteoclast differentiation. It suggests that CD97 may be an important mechanosensitive receptor during osteoclast differentiation. RNA sequencing analysis showed that the Rap1a/ERK signalling pathway mediates the effects of CD97 on osteoclast differentiation under compression. Consistently, we clarified that administration of the Rap1a inhibitor GGTI298 increased osteoclast activity, thereby accelerating tooth movement. In conclusion,our results indicate that CD97 suppresses osteoclast differentiation through the Rap1a/ERK signalling pathway under orthodontic compressive force.
文摘Giant cell tumors of the pancreas come in three varieties-osteoclastic,pleomorphic,and mixed histology.These tumors have distinctive endoscopic,clinical,and cytological features.Giant cell tumors have a controversial histogenesis,with some authors favoring an epithelial origin and others favoring a mesenchymal origin.The true origin of these lesions remains unclear at this time.These are also very rare tumors but proper identification and differentiation from more common pancreatic adenocarcinoma is important.The risk factors of these tumors and the prognosis may be different from those associated with standard pancreatic adenocarcinoma.Recognition of these differences can significantly affect patient care.These lesions have a unique appearance when imaged with endoscopic ultrasound(EUS),and these lesions can be diagnosed via EUS guided Fine Needle Aspiration(FNA).This manuscript will review the endoscopic,clinical,and pathologic features of these tumors.
基金supported by grants from the National Natural Science Foundation of China(nos.81820100820 and 81372845 to C.Z.,no.81400855 to C.Y.and no.82170893 to Q.T.)supported by National Key R&D Program of China grant no.2018YFC1106300(to C.Z.)+1 种基金Natural Science Foundation of Shanghai grant no.21ZR1448600(to C.Y.)Science and Technology Commission of Shanghai Municipality grant no.14pj1407200(to C.Y.)。
文摘Toll-like receptors(TLRs)play pivotal roles in inflammation and provide important links between the immune and skeletal systems.Although the activation of TLRs may affect osteoclast differentiation and bone metabolism,whether and how TLRs are required for normal bone remodeling remains to be fully explored.In the current study,we show for the first time that TLR9^(-/-)mice exhibit a low bone mass and low-grade systemic chronic inflammation,which is characterized by the expansion of CD4^(+)T cells and increased levels of inflammatory cytokines,including TNFα,RANKL,and IL1β.The increased levels of these cytokines significantly promote osteoclastogenesis and induce bone loss.Importantly,TLR9 deletion alters the gut microbiota,and this dysbiosis is the basis of the systemic inflammation and bone loss observed in TLR9^(-/-)mice.Furthermore,through single-cell RNA sequencing,we identified myeloid-biased hematopoiesis in the bone marrow of TLR9^(-/-)mice and determined that the increase in myelopoiesis,likely caused by the adaptation of hematopoietic stem cells to systemic inflammation,also contributes to inflammation-induced osteoclastogenesis and subsequent bone loss in TLR9^(-/-)mice.Thus,our study provides novel evidence that TLR9 signaling connects the gut microbiota,immune system,and bone and is critical in maintaining the homeostasis of inflammation,hematopoiesis,and bone metabolism under normal conditions.
文摘Rheumatoid arthritis(RA)and periodontitis are chronic inflammatory diseases leading to increased bone resorption.Preventing this inflammatory bone resorption is a major health challenge.Both diseases share immunopathogenic similarities and a common inflammatory environment.The autoimmune response or periodontal infection stimulates certain immune actors,leading in both cases to chronic inflammation that perpetuates bone resorption.Moreover,RA and periodontitis have a strong epidemiological association that could be explained by periodontal microbial dysbiosis.This dysbiosis is believed to be involved in the initiation of RA via three mechanisms.(i)The dissemination of periodontal pathogens triggers systemic inflammation.(ii)Periodontal pathogens can induce the generation of citrullinated neoepitopes,leading to the generation of anti-citrullinated peptide autoantibodies.(iii)Intracellular danger-associated molecular patterns accelerate local and systemic inflammation.Therefore,periodontal dysbiosis could promote or sustain bone resorption in distant inflamed joints.Interestingly,in inflammatory conditions,the existence of osteoclasts distinct from“classical osteoclasts”has recently been reported.They have proinflammatory origins and functions.Several populations of osteoclast precursors have been described in RA,such as classical monocytes,a dendritic cell subtype,and arthritis-associated osteoclastogenic macrophages.The aim of this review is to synthesize knowledge on osteoclasts and their precursors in inflammatory conditions,especially in RA and periodontitis.Special attention will be given to recent data related to RA that could be of potential value in periodontitis due to the immunopathogenic similarities between the two diseases.Improving our understanding of these pathogenic mechanisms should lead to the identification of new therapeutic targets involved in the pathological inflammatory bone resorption associated with these diseases.
基金NIH grant AR080021(Y.C.)The Penn Center for Musculoskeletal Disorders Histology Core(NIH P30-AR069619)。
文摘Osteoclasts are primary bone-resorbing cells,and receptor-activated NF-k B ligand(RANKL)stimulation is the key driver of osteoclast differentiation.During late-stage differentiation,osteoclasts become multinucleated and enlarged(so-called“maturation”),suggesting their need to adapt to changing metabolic demands and a substantial increase in size.Here,we demonstrate that immunoglobulin superfamily 11(Ig SF11),which is required for osteoclast differentiation through an association with the postsynaptic scaffolding protein PSD-95,regulates osteoclast differentiation by controlling the activity of pyruvate kinase M isoform2(PKM2).By using a system that directly induces the activation of Ig SF11 in a controlled manner,we identified PKM2 as a major Ig SF11-induced tyrosine-phosphorylated protein.Ig SF11 activates multiple Src family tyrosine kinases(SFKs),including c-Src,Fyn,and Hc K,which phosphorylate PKM2 and thereby inhibit PKM2 activity.Consistently,Ig SF11-deficient cells show higher PKM2activity and defective osteoclast differentiation.Furthermore,inhibiting PKM2 activities with the specific inhibitor Shikonin rescues the impaired osteoclast differentiation in Ig SF11-deficient cells,and activating PKM2 with the specific activator TEPP46 suppresses osteoclast differentiation in wild-type cells.Moreover,PKM2 activation further suppresses osteoclastic bone loss without affecting bone formation in vivo.Taken together,these results show that Ig SF11 controls osteoclast differentiation through PKM2 activity,which is a metabolic switch necessary for optimal osteoclast maturation.
基金supported by the National Natural Science Foundation of China(grant No.81972041)the Beijing Natural Science Foundation(grant No.7172112)。
文摘Glycans,either alone or in complex with glycan-binding proteins,are essential structures that can regulate cell biology by mediating protein stability or receptor dimerization under physiological and pathological conditions.Certain glycans are ligands for lectins,which are carbohydrate-specific receptors.Bone is a complex tissue that provides mechanical support for muscles and joints,and the regulation of bone mass in mammals is governed by complex interplay between bone-forming cells,called osteoblasts,and bone-resorbing cells,called osteoclasts.Bone erosion occurs when bone resorption notably exceeds bone formation.Osteoclasts may be activated during cancer,leading to a range of symptoms,including bone pain,fracture,and spinal cord compression.Our understanding of the role of protein glycosylation in cells and tissues involved in osteoclastogenesis suggests that glycosylation-based treatments can be used in the management of diseases.The aims of this review are to clarify the process of bone resorption and investigate the signaling pathways mediated by glycosylation and their roles in osteoclast biology.Moreover,we aim to outline how the lessons learned about these approaches are paving the way for future glycobiology-focused therapeutics.
基金supported by the National Natural Science Foundation of China(81871789,81802200,82172387)the Natural Science Foundation of Jiangsu Province(BK20180052)the Gusu Health Talents Program(GSWS2020023)。
文摘Background:Wear particles-induced osteolysis is a major long-term complication after total joint arthroplasty.Up to now,there is no effective treatment for wear particles-induced osteolysis except for the revision surgery,which is a heavy psychological and economic burden to patients.A metabolite of gut microbiota,short chain fatty acids(SCFAs),has been reported to be beneficial for many chronic inflammatory diseases.This study aimed to investigate the therapeutic effect of SCFAs on osteolysis.Methods:A model of inflammatory osteolysis was established by applying CoCrMo alloy particles to mouse calvarium.After two weeks of intervention,the anti-inflammatory effects of SCFAs on wear particle-induced osteolysis were evaluated by micro-CT analysis and immunohistochemistry staining.In vitro study,lipopolysaccharide(LPS)primed bone marrow-derived macrophages(BMDMs)and Tohoku hospital pediatrics-1(THP-1)macrophages were stimulated with CoCrMo particles to activate inflammasome in the presence of acetate(C2),propionate(C3),and butyrate(C4).Western blotting,enzyme-linked immunosorbent assay,and immunofluorescence were used to detect the activation of NLRP3 inflammasome.The effects of SCFAs on osteoclasts were evaluate by qRT-PCR,Western blotting,immunofluorescence,and tartrate-resistant acid phosphatase(TRAP)staining.Additionally,histone deacetylase(HDAC)inhibitors,agonists of GPR41,GPR43,and GPR109A were applied to confirm the underlying mechanism of SCFAs on the inflammasome activation of macrophages and osteoclastogenesis.Results:C3 and C4 but not C2 could alleviate wear particles-induced osteolysis with fewer bone erosion pits(P<0.001),higher level of bone volume to tissue volume(BV/TV,P<0.001),bone mineral density(BMD,P<0.001),and a lower total porosity(P<0.001).C3 and C4 prevented CoCrMo alloy particles-induced ASC speck formation and nucleationinduced oligomerization,suppressing the cleavage of caspase-1(P<0.05)and IL-1β(P<0.05)stimulated by CoCrMo alloy particles.C3 and C4 also inhibited the generation of gasdermin D-N-terminal fragment(GSDMD-NT)to regulate pyroptosis.Besides,C3 and C4 have a negative impact on osteoclast differentiation(P<0.05)and its function(P<0.05),affecting the podosome arrangement and morphologically normal podosome belts formation.Conclusions:Our work showed that C3 and C4 are qualified candidates for the treatment of wear particle-induced osteolysis.
基金supported by the Beijing Municipal Natural Science Foundation(7192110)。
文摘Objective:To investigate whether acupotomy could inhibit subchondral bone remodeling in knee osteoarthritis(KOA)rabbits by regulating the activity of osteoblasts and osteoclasts.Methods:KOA rabbits were prepared by immobilization for 6 and 9 weeks by Videman method.Nine groups of rabbits(control,6 weeks and 9 weeks model,6 weeks and 9 weeks acupotomy,6 weeks and 9 weeks electroacupuncture,and 6 weeks and 9 weeks drug groups)received acupotomy,electroacupuncture and risedronate sodium intervention,respectively,for 3 weeks.Results:Acupotomy can inhibit the activity of osteoclasts and osteoblasts in subchondral bone by reducing the proteins expression of cathepsin K(CK)and tartrate-resistant acid phosphatase(TRAP)and decreasing the proteins expression of osteocalcin(OCN)and alkaline phosphatase(ALP),to intercept the abnormal bone resorption and bone formation of subchondral bone in 6-week and 9-week immobilization-induced KOA rabbits.Conclusion:These findings indicated that acupotomy may be more advantageous than risedronate sodium intervention in modulating subchondral bone remodeling in KOA rabbits,especially in 9-week immobilization-induced KOA rabbits.
文摘BACKGROUND Invasive breast carcinoma with osteoclast-like stromal giant cells(OGCs) is an extremely rare morphology of breast carcinomas.To the best of our knowledge,the most recent case report describing this rare pathology was published six years ago.The mechanism controlling the development of this unique histological formation is still unknown.Further,the prognosis of patients with OGC involvement is also controversial.CASE SUMMARY We report the case of a 48-year-old woman,who presented to the outpatient department with a palpable,growing,painless mass in her left breast for about one year.Sonography and mammography revealed a 26.5 mm ×18.8 mm asymmetric,lobular mass with circumscribed margin and the Breast Imaging Reporting and Data System was category 4C.Sono-guided aspiration biopsy revealed invasive ductal carcinoma.The patient underwent breast conserving surgery and was diagnosed with invasive breast carcinoma with OGCs,grade Ⅱ,with intermediate grade of ductal carcinoma in situ(ER:80%,3+,PR:80%,3+,HER-2:negative,Ki 67:30%).Adjuvant chemotherapy and post-operation radiotherapy were initiated thereafter.CONCLUSION As a rare morphology of breast cancer,breast carcinoma with OGC occurs most often in relatively young women,has less lymph node involvement,and its occurrence is not racedependent.
基金National Natural Science Foundation Project(No.81260275)。
文摘Bone sialoprotein(BSP)is an important non-collagen extracellular matrix protein(EMC)that promotes bone formation and induces bone resorption.BSP is secreted by odontoblasts,it plays an important role in cementum,alveolar bone formation and mineralization,and periodontal function.Bone resorption is controlled by a complex molecular network,and BSP can promote osteoclast differentiation and bone resorption.It is also associated with the metastasis of a range of malignancies.Osteoclasts(OC)are thought to be the only cells involved in bone resorption and play an important role in bone formation and late developmental remodeling.Osteoporosis and periodontal disease are caused by excessive bone resorption.This article will summarize the osteoclasts differentiation,the biological function of bone resorption,and explore the progress of the prevention and treatment of the related bone resorption diseases such as osteoporosis and periodontal disease through the regulation of osteoclasts.
基金National Natural Science Foundation of China(No.81860645)Hainan Medical University Introduced Talents Research Start-Up Funds(No.2015)。
文摘Objective:To investigate whether miR-483-5p regulates osteoclast generation by targeting Timp2.miR-483-5p can promote osteoclast differentiation and bone destruction.Methods:Target genes of miR-483-5p were predicted by miRNAs target gene prediction software TargetScan8.0,and wild type and mutant 3'UTR plasmids were constructed.Dual luciferase reporter genes were used to verify whether target genes had a targeted regulatory relationship with miR-483-5p.Western blotting was used to detect the corresponding changes in the expression level of target protein after adjusting the level of miR-483-5p in cells.Cells were transfected or infected with target gene siRNA or target protein lentivirus,and TRAP staining and q-PCR assays were performed.In addition,for osteoclast induction experiment,RAW264.7 cells were co-transfected with ago-miR-483-5p and target protein-overexpressed lentiviruses q-PCR and TRAP staining were performed respectively.Results:Bioinformatics software was used to predict the target gene of miR-483-5p,and the Timp2 gene was found to regulate osteoclasts,and the dual luciferase reporter detection system found that miR-483-5p could be associated with the 3-UTR of the predicted target gene Timp2 gene.There are complementary loci and targeted regulatory relationship between them.Subsequently,we upregulated miR-483-5p in RAW264.7 cells to reduce the expression of Timp2.Compared with the normal group,the number of osteoclasts and the expression of osteoclast-specific genes increased significantly after the induction of Timp2 in knockdown cells.After co-transfection of target gene and miR-483-5p into cells,the number of osteoclasts and the expression of specific genes decreased significantly compared with the normal group.Conclusion:Timp2 is a downstream target gene of miR-483-5p and is involved in and inhibits osteoclast generation.
文摘目的探讨免疫调节分子IL-33对绝经后骨质疏松症(postmenopausal osteoporosis,PMOP)模型鼠RANKL/c-Fos/NFATc1信号轴的调控作用及藤黄健骨胶囊(Tenghuang Jiangu capsule,TJC)的干预机制。方法构建PMOP大鼠模型,设置假手术组、PMOP模型组、阳性对照组(0.09 mg/kg)和TJC高、中、低剂量组(0.36、0.18、0.09 g/kg),灌胃给药,每天1次,持续8周。从大鼠末次给药后体质量、骨密度(bone mineral density,BMD)及股骨组织微结构等方面评价TJC的疗效;通过ELISA分析TJC对大鼠血清免疫调节因子IL-33、IL-1、IL-31变化;运用qPCR和Western blotting分析TJC对大鼠股骨OPG、RANKL、RANK、c-Fos、NFATc1表达量的影响。结果与假手术组相比,PMOP模型组大鼠的体质量、骨髓脂肪组织相对面积(relative area of bone marrow adipose tissue,BMAT),IL-1、IL-31变化,RANKL、RANK、c-Fos、NFATc1的表达均出现了明显升高的趋势,而BMD、IL-33变化、OPG的表达则出现了明显下降的趋势(P<0.01);与PMOP模型组相比,TJC高剂量组大鼠体质量出现显著下降趋势、IL-33变化出现显著升高趋势(P<0.01),TJC中、高剂量组大鼠BMAT、RANK的表达出现显著下降趋势、OPG的表达出现显著升高趋势(P<0.05或P<0.01),TJC各剂量组大鼠IL-1、IL-31变化,RANKL、c-Fos、NFATc1出现显著降低趋势,BMD出现显著增加趋势(P<0.05或P<0.01)。结论TJC能够提高PMOP大鼠免疫调控分子IL-33含量,抑制免疫调控分子IL-1、IL-31含量和破骨细胞分化标志分子NFATc1的表达,其机制可能与RANKL/c-Fos/NFATc1抑制骨代谢通路密切相关。