Concomitantly with the increase in the prevalences of overweight/obesity, nonalcoholic fatty liver disease(NAFLD) has worldwide become the main cause of chronic liver disease in both adults and children. Patients with...Concomitantly with the increase in the prevalences of overweight/obesity, nonalcoholic fatty liver disease(NAFLD) has worldwide become the main cause of chronic liver disease in both adults and children. Patients with fatty liver display features of metabolic syndrome(Met S), like insulin resistance(IR), glucose intolerance, hypertension and dyslipidemia. Recently, epidemiological studies have linked obesity, Met S, and NAFLD to decreased bone mineral density and osteoporosis, highlighting an intricate interplay among bone, adipose tissue, and liver. Osteoprotegerin(OPG), an important symbol of the receptor activator of nuclear factor-B ligand/receptor activator of nuclear factor kappa B/OPG system activation, typically considered for its role in bone metabolism, may also play critical roles in the initiation and perpetuation of obesityrelated comorbidities. Clinical data have indicated that OPG concentrations are associated with hypertension, left ventricular hypertrophy, vascular calcification, endothelial dysfunction, and severity of liver damage in chronic hepatitis C. Nonetheless, the relationship between circulating OPG and IR as a key feature of Met S as well as between OPG and NAFLD remains uncertain. Thus, the aims of the present review are to provide the existent knowledge on these associations and to discuss briefly the underlying mechanisms linking OPG and NAFLD.展开更多
Vascular calcifications are commonly observed in patients with chronic kidney disease (CKD) and contri-bute to the excessive cardiovascular morbidity and mortality rates observed in these patients populations. Altho...Vascular calcifications are commonly observed in patients with chronic kidney disease (CKD) and contri-bute to the excessive cardiovascular morbidity and mortality rates observed in these patients populations. Although the pathogenetic mechanisms are not yet fully elucidated, recent evidence suggests a link between bone metabolism and the development and progression of vascular calcifications. Moreover, accumulating data indicate that receptor activator of nuclear factor κB ligand/osteoprotegerin axis which plays essential roles in the regulation of bone metabolism is also involved in extra-osseous bone formation. Further studies are required to establish the prognostic significance of the above biomarkers as predictors of the presence and severity of vascular calcifications in CKD patients and of cardiovascular morbidity and mortality. Moreover, randomized clinical trials are needed to clarify whether inhibition of osteoclast activity will protect from vascular calcifcations.展开更多
The effect of triptolide (TP) on the expression of receptor activator of nuclear factor-κB ligand (RANKL) and osteoprotegerin (OPG) was explored in rat adjuvant induced arthritis (AA). AA was induced in Wista...The effect of triptolide (TP) on the expression of receptor activator of nuclear factor-κB ligand (RANKL) and osteoprotegerin (OPG) was explored in rat adjuvant induced arthritis (AA). AA was induced in Wistar rats. Arthritis rats were treated with TP and methotrexate (MTX) at the onset (day 9) of arthritis. On the peak of arthritis (day 24), the expression of RANKL and OPG protein in the joints and RANKL mRNA in peripheral blood mononuclear cells (PBMC) was detected. TNF-α and IL-1β levels in peripheral blood were determined. Bone erosion scores were also evaluated. The results showed that bone erosion scores in TP and MTX groups were lower than in AA group (.P〈0.01) ; The expression levels of RANKL in the synovium (P〈0.01) and bone (P〈0.05), and OPG level in synovium (P〈0.05) were lower in TP group than in AA group (P〈0.05). In TP group, the expression levels of RANKL mRNA and TNF-α, IL-1β in PBMC were lower than in AA group (all P〈0.01). It was concluded that TP could inhibit rat adjuvant arthritis bone erosion by suppressing the expression of RANKL.展开更多
Objective To study the effect of baicalin on the expression of receptor activator of nuclear factor-κB ligand(RANKL)and osteoprotegerin(OPG)in cultured human periodontal ligament(HPDL)cells.Methods Small interfering ...Objective To study the effect of baicalin on the expression of receptor activator of nuclear factor-κB ligand(RANKL)and osteoprotegerin(OPG)in cultured human periodontal ligament(HPDL)cells.Methods Small interfering RNA(siRNA)eukaryotic expression vector targeted transforming growth factor βⅡ receptor(TGF-β RⅡ)was constructed and transfected into T cells.HPDL cells with T cells transfected with siRNA or not were placed in the culture medium that had been added with lipopolysaccharide(LPS)and baicalin.The obtained solution was divided into six groups according to the components(group Ⅰ:HPDL cells+LPS+T cells transfected with siRNA1+baicalin;group Ⅱ:HPDL cells+LPS+T cells transfected with siRNA1;group Ⅲ:HPDL cells+LPS+T cells+baicalin;group Ⅳ:HPDL cells+LPS+T cells;group Ⅴ:HPDL cells+baicalin;group Ⅵ:HPDL cells)and was cultured for 48 hours.RT-PCR was used to observe the effect of baicalin on the expression of OPG-RANKL in HPDL cells.Results The ratio of RANKL/OPG in group Ⅰ was lower than that in group Ⅱ(P<0.01)and higher than that in group Ⅲ(P<0.01);The ratio of RANKL/OPG in group Ⅲ was lower than that in group Ⅳ(P<0.01);the ratio of RANKL/OPG in group Ⅳ was higher than that in group Ⅵ(P<0.01);the ratio of RANKL/OPG in group Ⅴ was lower than that in group Ⅵ(P<0.05).Conclusion ① Baicalin could decrease the ratio of RANKL/OPG in HPDL cells.② The TGF-β signaling transduction plays an important role in the effect of baicalin on the RANKL/OPG ratio in HPDL cells.③ Baicalin acts not only through TGF-β to regulate RANKL/OPG in HPDL cells,but also through other pathways.展开更多
Extracellular amyloid beta(Aβ) plaques are main pathological feature of Alzheimer’s disease.However,the specific type of neuro ns that produce Aβ peptides in the initial stage of Alzheimer’s disease are unknown.In...Extracellular amyloid beta(Aβ) plaques are main pathological feature of Alzheimer’s disease.However,the specific type of neuro ns that produce Aβ peptides in the initial stage of Alzheimer’s disease are unknown.In this study,we found that 5-hydroxytryptamin receptor 3A subunit(HTR3A) was highly expressed in the brain tissue of transgenic amyloid precursor protein and presenilin-1 mice(an Alzheimer’s disease model) and patients with Alzheimer’s disease.To investigate whether HTR3A-positive interneurons are associated with the production of Aβ plaques,we performed double immunostaining and found that HTR3A-positive interneurons were clustered around Aβ plaques in the mouse model.Some amyloid precursor protein-positive or β-site amyloid precursor protein cleaving enzyme-1-positive neurites near Aβ plaques were co-localized with HTR3A interneurons.These results suggest that HTR3A-positive interneurons may partially contribute to the generation of Aβ peptides.We treated 5.0-5.5-month-old model mice with tro pisetron,a HTR3 antagonist,for 8 consecutive weeks.We found that the cognitive deficit of mice was partially reversed,Aβ plaques and neuroinflammation we re remarkably reduced,the expression of HTR3 was remarkably decreased and the calcineurin/nuclear factor of activated T-cell 4 signaling pathway was inhibited in treated model mice.These findings suggest that HTR3A interneurons partly contribute to generation of Aβ peptide at the initial stage of Alzheimer’s disease and inhibiting HTR3 partly reve rses the pathological changes of Alzheimer’s disease.展开更多
地舒单抗(denosumab,DMAb)是最早出现的全人源核因子-κB受体活化因子配体[receptor activator of nuclear factor-κB(NF-κB)ligand,RANKL]的单克隆抗体。2020年在我国上市,应用于骨质疏松治疗领域,是抑制骨吸收类抗骨松药物中的新成...地舒单抗(denosumab,DMAb)是最早出现的全人源核因子-κB受体活化因子配体[receptor activator of nuclear factor-κB(NF-κB)ligand,RANKL]的单克隆抗体。2020年在我国上市,应用于骨质疏松治疗领域,是抑制骨吸收类抗骨松药物中的新成员。本综述的目的为归纳总结近年围绕DMAb在骨质疏松初始、序贯以及联合治疗方面的临床研究进展,为其应用提供参考。展开更多
Background:Obstructive sleep apnea-hypopnea syndrome (OSAHS) is associated with a higher prevalence of osteoporosis.However,the underlying mechanisms linking OSAHS with bone loss are still unclear.The aim of this stud...Background:Obstructive sleep apnea-hypopnea syndrome (OSAHS) is associated with a higher prevalence of osteoporosis.However,the underlying mechanisms linking OSAHS with bone loss are still unclear.The aim of this study was to investigate the changes of receptor activator of nuclear factor-κB ligand (RANKL,an osteoclastogenesis-promoting factor) and osteoprotegerin (OPG,the decoy receptor for RANKL),oxidative stress and bone metabolism markers in OSAHS,in order to understand the potential mechanisms underlying bone loss in OSAHS patients.Methods:Forty-eight male patients with OSAHS,confirmed by polysomnography (PSG) study,were enrolled.Twenty male subjects who were confirmed as not having OSAHS served as the controls.The subjects’bone mineral density (BMD) was assessed in lumbar spine and femoral neck using dual-energy X-ray absorptiometry (DXA).Blood samples were collected from all subjects for measurement of RANKL,OPG,the bone formation marker bone-specific alkaline phosphatase (BAP),the bone resorption marker tartrate-resistant acid phosphatase 5b (TRAP-5b),and total antioxidant capacity (TAOC).Results:The BMD and the T-score of the femoral neck and the lumbar spine were significantly lower in OSAHS patients as compared to the control group (P< 0.05).The serum level of BAP was significantly decreased in the OSAHS group (15.62 ± 5.20 μg/L) as compared to the control group (18.83 ± 5.50 μg/L,t= -2.235,P< 0.05),while the levels of TRAP-5b did not differ between the two groups (t= -1.447,P> 0.05).The serum level of OPG and the OPG/RANKL ratio were lower in the OSAHS group compared to the control group (bothP< 0.05).TAOC level was also decreased significantly in the OSAHS group (P< 0.05).Correlation analysis showed that the TAOC level was positively correlated with BAP in the OSAHS group (r= 0.248,P= 0.04),but there were no correlations between TAOC and the BMD or the T-scores.The correlations between the level of OPG (or the OPG/RANKL ratio) and BMD or TAOC did not reach significance.Conclusion:In OSAHS patients,lower levels of TAOC were associated with decreased bone formation,suggesting a role of oxidative stress in bone loss,while the role of OPG/RANKL imbalance in bone metabolism in OSAHS needs further evaluation .展开更多
Background The cannabinoid receptor-2 (CB2) is important for bone remodeling. In this study, we investigated the effects of CB2 selective antagonist (AM630) on receptor activator of nuclear factor kappa B (RANK)...Background The cannabinoid receptor-2 (CB2) is important for bone remodeling. In this study, we investigated the effects of CB2 selective antagonist (AM630) on receptor activator of nuclear factor kappa B (RANK) ligand (RANKL)induced osteoclast differentiation and the underlying signaling pathway using a monocyte-macrophage cell line-RAW264.7.Methods RAW264.7 was cultured with RANKL for 6 days and then treated with AM630 for 24 hours. Mature osteoclasts were measured by tartrate-resistant acid phosphatase (TRAP) staining using a commercial kit. Total ribonucleic acid (RNA)was isolated and real-time reverse transcriptase-polymerase chain reaction (RT-PCR) was done to examine the expression of RANK, cathepsin K (CPK) and nuclear factor kappa B (NF-κB). The extracellular signal-regulated kinase (ERK),phosphorylation of ERK (P-ERK) and NF-κB production were tested by Western blotting. The effect of AM630 on RAW264.7 viability was determined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide (MTT) assay.Results AM630 did not affect the viability of RAW264.7. However, this CB2 selective antagonist markedly inhibited osteoclast formation and the inhibition rate was dose-dependent. The dose of 〉100 nmol/L could reduce TRAP positive cells to the levels that were significantly lower than the control. AM630 suppressed the expression of genes associated with osteoclast differentiation and activation, such as RANK and CPK. An analysis of a signaling pathway showed that AM630 inhibited the RANKL-induced activation of ERK, but not NF-κB.Conclusion AM630 could inhibit the osteoclastogenesis from RAW264.7 induced with RANKL.展开更多
Background Receptor activator of nuclear factor kappa B (NF-κB) ligand (RANKL) and osteoprotegerin (OPG) have been recently shown to play important roles in bone resorption. The aim of this study was to investi...Background Receptor activator of nuclear factor kappa B (NF-κB) ligand (RANKL) and osteoprotegerin (OPG) have been recently shown to play important roles in bone resorption. The aim of this study was to investigate the possible association between the expression of bone resorption regulators (RANKL and OPG) and inflammatory cell infiltration in chronic apical periodontitis.Methods The samples of chronic periapical lesions (n=40) and healthy periapical tissues (n=10) were examined for immunohistochemical analysis of RANKL and OPG. Lesion samples were further analyzed for the inflammatory infiltration condition. The inflammatory cell infiltration was scored in relation to immunohistochemical reactivity for CD3, CD20 and CD68.Results The number of RANKL-positive cells and the ratio of RANKL/OPG in chronic apical periodontitis were significantly higher than those in healthy periapical tissues (P<0.001). The number of RANKL-positive cells was higher in lesions with severe inflammatory infiltration than in those with light inflammatory infiltration (P<0.05). Significantly increased RANKL expression was found with T lymphocytes (CD3+), macrophages (CD68+) and B lymphocytes (CD20+)infiltration (P<0.05). No association was found between the ratio of RANKL/OPG and inflammatory cell infiltration.Conclusions RANKL expression was increased with T, B lymphocytes and macrophages infiltration, respectively in chronic periapical lesions. RANKL appears to be closely related to periapical inflammatory infiltrates. The relative ratio of RANKL/OPG may be a key determinant of RANKL-mediated bone resorption.展开更多
Objective: To study the effect of Wenhua Juanbi Recipe(温化蠲痹方, WJR) on expression of receptor activator of nuclear factor kappa B ligand(RANKL), osteoprotegerin(OPG), and tumor necrosis factor receptor supe...Objective: To study the effect of Wenhua Juanbi Recipe(温化蠲痹方, WJR) on expression of receptor activator of nuclear factor kappa B ligand(RANKL), osteoprotegerin(OPG), and tumor necrosis factor receptor superfamily member 14(TNFRSF14, also known as LIGHT) in rats with collagen-induced arthritis(CIA). Methods: CIA rats were generated by subcutaneous injection of bovine collagen type-Ⅱ at the tail base. Sixty CIA rats were randomly assigned(10 animals/group) to: model, methotrexate(MTX)-treated(0.78 mg/kg body weight), and WJR-treated(22.9 g/kg) groups. Healthy normal rats(n=10) were used as the normal control. Treatments or saline were administered once daily by oral gavage. Rats were sacrificed at day 28 post-treatment and knee synovium and peripheral blood serum were collected. Toe swelling degree and expression of RANKL, OPG, and LIGHT were determined by Western blot and immunohistochemistry. Results: Compared with the normal group, toe swelling degree was significantly increased in the model group(P〈0.01). After treatment, toe swelling degree decreased significantly in the WJR and MTX groups compared with the model group(P〈0.01). Compared with the normal group, expression of RANKL and LIGHT were significantly increased and OPG significantly decreased in peripheral blood and synovium of the model group(P〈0.01). Conversely, RANKL and LIGHT expression were significantly reduced and OPG increased in the WJR and MTX groups compared with the model group(P〈0.01). No statistically significant difference existed between WJR and MTX groups. Conclusion: WJR likely acts by reducing RANKL expression and increasing OPG expression, thus inhibiting RANKL/RANK interaction and reducing LIGHT expression, thereby inhibiting osteoclast formation/activation to block bone erosion.展开更多
Background Pancreatic beta-cell apoptosis induced by lipotoxicity, to a large extent, contributes to the progression of type 2 diabetes. To investigate the mechanism of free fatty acid induced apoptosis, we aimed to s...Background Pancreatic beta-cell apoptosis induced by lipotoxicity, to a large extent, contributes to the progression of type 2 diabetes. To investigate the mechanism of free fatty acid induced apoptosis, we aimed to study the effects of palmitic acid (PA) on the apoptosis and peroxisome proliferator-activated receptor y coactivator-1α (PGC-1α) expression in βTC3 cells as well as the possible role of nuclear factor-KB (NF-KB) in this process. Methods Hoechst 33258 was used to detect βTC3 cell apoptosis, which was induced by PA stimulation for 12 hours. PGC-1α expression was analyzed by reverse transcription polymerase chain reaction, IκB kinase β (IKKβ), IκBα NF-KB-inducing kinase (NIK) and ReI-B expressions were analyzed by Western blotting. MGβ2 was employed to block the endogenous IκBαdegradation before PA administration, and then its effect on PA-inducing cell apoptosis and PGC-1α mRNA expression was analyzed. Results Significant increased cell apoptosis was found at the concentration of 0.5 mmol/L and 1.0 mmol/L PA administration. PA (0.5 mmol/L) could extensively reduced the expression of PGC-1α mRNA. After exposing βTC3 cells to 0.5 mmol/L PA for different time periods (0, 4, 6, 8, 10 and 12 hours), IKKβ protein expression increased while IκBα NIK and ReI-B protein expression declined in a time-dependent manner. Pretreatment with MGβ2 to inhibit the degradation of IκBα partially prevented the down-regulation of PGC-1α mRNA expression after 12-hour PA treatment in accordance with the decrease of PA induced apoptosis. Conclusions NF-KB canonical pathway was activated in PA-mediated βTC3 cell apoptosis, whereas non-canonical pathway was inhibited. Reduced PGC-1α expression by PA in βTC3 cells could involve the activation of canonical NF-KB pathway, so as to deteriorate the PA induced apoptosis.展开更多
文摘Concomitantly with the increase in the prevalences of overweight/obesity, nonalcoholic fatty liver disease(NAFLD) has worldwide become the main cause of chronic liver disease in both adults and children. Patients with fatty liver display features of metabolic syndrome(Met S), like insulin resistance(IR), glucose intolerance, hypertension and dyslipidemia. Recently, epidemiological studies have linked obesity, Met S, and NAFLD to decreased bone mineral density and osteoporosis, highlighting an intricate interplay among bone, adipose tissue, and liver. Osteoprotegerin(OPG), an important symbol of the receptor activator of nuclear factor-B ligand/receptor activator of nuclear factor kappa B/OPG system activation, typically considered for its role in bone metabolism, may also play critical roles in the initiation and perpetuation of obesityrelated comorbidities. Clinical data have indicated that OPG concentrations are associated with hypertension, left ventricular hypertrophy, vascular calcification, endothelial dysfunction, and severity of liver damage in chronic hepatitis C. Nonetheless, the relationship between circulating OPG and IR as a key feature of Met S as well as between OPG and NAFLD remains uncertain. Thus, the aims of the present review are to provide the existent knowledge on these associations and to discuss briefly the underlying mechanisms linking OPG and NAFLD.
文摘Vascular calcifications are commonly observed in patients with chronic kidney disease (CKD) and contri-bute to the excessive cardiovascular morbidity and mortality rates observed in these patients populations. Although the pathogenetic mechanisms are not yet fully elucidated, recent evidence suggests a link between bone metabolism and the development and progression of vascular calcifications. Moreover, accumulating data indicate that receptor activator of nuclear factor κB ligand/osteoprotegerin axis which plays essential roles in the regulation of bone metabolism is also involved in extra-osseous bone formation. Further studies are required to establish the prognostic significance of the above biomarkers as predictors of the presence and severity of vascular calcifications in CKD patients and of cardiovascular morbidity and mortality. Moreover, randomized clinical trials are needed to clarify whether inhibition of osteoclast activity will protect from vascular calcifcations.
文摘The effect of triptolide (TP) on the expression of receptor activator of nuclear factor-κB ligand (RANKL) and osteoprotegerin (OPG) was explored in rat adjuvant induced arthritis (AA). AA was induced in Wistar rats. Arthritis rats were treated with TP and methotrexate (MTX) at the onset (day 9) of arthritis. On the peak of arthritis (day 24), the expression of RANKL and OPG protein in the joints and RANKL mRNA in peripheral blood mononuclear cells (PBMC) was detected. TNF-α and IL-1β levels in peripheral blood were determined. Bone erosion scores were also evaluated. The results showed that bone erosion scores in TP and MTX groups were lower than in AA group (.P〈0.01) ; The expression levels of RANKL in the synovium (P〈0.01) and bone (P〈0.05), and OPG level in synovium (P〈0.05) were lower in TP group than in AA group (P〈0.05). In TP group, the expression levels of RANKL mRNA and TNF-α, IL-1β in PBMC were lower than in AA group (all P〈0.01). It was concluded that TP could inhibit rat adjuvant arthritis bone erosion by suppressing the expression of RANKL.
基金supported by the Foundation of Stomatology Hospital,Xi'an Jiaotong University
文摘Objective To study the effect of baicalin on the expression of receptor activator of nuclear factor-κB ligand(RANKL)and osteoprotegerin(OPG)in cultured human periodontal ligament(HPDL)cells.Methods Small interfering RNA(siRNA)eukaryotic expression vector targeted transforming growth factor βⅡ receptor(TGF-β RⅡ)was constructed and transfected into T cells.HPDL cells with T cells transfected with siRNA or not were placed in the culture medium that had been added with lipopolysaccharide(LPS)and baicalin.The obtained solution was divided into six groups according to the components(group Ⅰ:HPDL cells+LPS+T cells transfected with siRNA1+baicalin;group Ⅱ:HPDL cells+LPS+T cells transfected with siRNA1;group Ⅲ:HPDL cells+LPS+T cells+baicalin;group Ⅳ:HPDL cells+LPS+T cells;group Ⅴ:HPDL cells+baicalin;group Ⅵ:HPDL cells)and was cultured for 48 hours.RT-PCR was used to observe the effect of baicalin on the expression of OPG-RANKL in HPDL cells.Results The ratio of RANKL/OPG in group Ⅰ was lower than that in group Ⅱ(P<0.01)and higher than that in group Ⅲ(P<0.01);The ratio of RANKL/OPG in group Ⅲ was lower than that in group Ⅳ(P<0.01);the ratio of RANKL/OPG in group Ⅳ was higher than that in group Ⅵ(P<0.01);the ratio of RANKL/OPG in group Ⅴ was lower than that in group Ⅵ(P<0.05).Conclusion ① Baicalin could decrease the ratio of RANKL/OPG in HPDL cells.② The TGF-β signaling transduction plays an important role in the effect of baicalin on the RANKL/OPG ratio in HPDL cells.③ Baicalin acts not only through TGF-β to regulate RANKL/OPG in HPDL cells,but also through other pathways.
基金supported by the Notional Natural Science Foundation of China,Nos.81371213 and 8107098 7the Natural Science Foundation of Shanghai,No.21ZR1468400 (all to QLY)。
文摘Extracellular amyloid beta(Aβ) plaques are main pathological feature of Alzheimer’s disease.However,the specific type of neuro ns that produce Aβ peptides in the initial stage of Alzheimer’s disease are unknown.In this study,we found that 5-hydroxytryptamin receptor 3A subunit(HTR3A) was highly expressed in the brain tissue of transgenic amyloid precursor protein and presenilin-1 mice(an Alzheimer’s disease model) and patients with Alzheimer’s disease.To investigate whether HTR3A-positive interneurons are associated with the production of Aβ plaques,we performed double immunostaining and found that HTR3A-positive interneurons were clustered around Aβ plaques in the mouse model.Some amyloid precursor protein-positive or β-site amyloid precursor protein cleaving enzyme-1-positive neurites near Aβ plaques were co-localized with HTR3A interneurons.These results suggest that HTR3A-positive interneurons may partially contribute to the generation of Aβ peptides.We treated 5.0-5.5-month-old model mice with tro pisetron,a HTR3 antagonist,for 8 consecutive weeks.We found that the cognitive deficit of mice was partially reversed,Aβ plaques and neuroinflammation we re remarkably reduced,the expression of HTR3 was remarkably decreased and the calcineurin/nuclear factor of activated T-cell 4 signaling pathway was inhibited in treated model mice.These findings suggest that HTR3A interneurons partly contribute to generation of Aβ peptide at the initial stage of Alzheimer’s disease and inhibiting HTR3 partly reve rses the pathological changes of Alzheimer’s disease.
文摘地舒单抗(denosumab,DMAb)是最早出现的全人源核因子-κB受体活化因子配体[receptor activator of nuclear factor-κB(NF-κB)ligand,RANKL]的单克隆抗体。2020年在我国上市,应用于骨质疏松治疗领域,是抑制骨吸收类抗骨松药物中的新成员。本综述的目的为归纳总结近年围绕DMAb在骨质疏松初始、序贯以及联合治疗方面的临床研究进展,为其应用提供参考。
文摘Background:Obstructive sleep apnea-hypopnea syndrome (OSAHS) is associated with a higher prevalence of osteoporosis.However,the underlying mechanisms linking OSAHS with bone loss are still unclear.The aim of this study was to investigate the changes of receptor activator of nuclear factor-κB ligand (RANKL,an osteoclastogenesis-promoting factor) and osteoprotegerin (OPG,the decoy receptor for RANKL),oxidative stress and bone metabolism markers in OSAHS,in order to understand the potential mechanisms underlying bone loss in OSAHS patients.Methods:Forty-eight male patients with OSAHS,confirmed by polysomnography (PSG) study,were enrolled.Twenty male subjects who were confirmed as not having OSAHS served as the controls.The subjects’bone mineral density (BMD) was assessed in lumbar spine and femoral neck using dual-energy X-ray absorptiometry (DXA).Blood samples were collected from all subjects for measurement of RANKL,OPG,the bone formation marker bone-specific alkaline phosphatase (BAP),the bone resorption marker tartrate-resistant acid phosphatase 5b (TRAP-5b),and total antioxidant capacity (TAOC).Results:The BMD and the T-score of the femoral neck and the lumbar spine were significantly lower in OSAHS patients as compared to the control group (P< 0.05).The serum level of BAP was significantly decreased in the OSAHS group (15.62 ± 5.20 μg/L) as compared to the control group (18.83 ± 5.50 μg/L,t= -2.235,P< 0.05),while the levels of TRAP-5b did not differ between the two groups (t= -1.447,P> 0.05).The serum level of OPG and the OPG/RANKL ratio were lower in the OSAHS group compared to the control group (bothP< 0.05).TAOC level was also decreased significantly in the OSAHS group (P< 0.05).Correlation analysis showed that the TAOC level was positively correlated with BAP in the OSAHS group (r= 0.248,P= 0.04),but there were no correlations between TAOC and the BMD or the T-scores.The correlations between the level of OPG (or the OPG/RANKL ratio) and BMD or TAOC did not reach significance.Conclusion:In OSAHS patients,lower levels of TAOC were associated with decreased bone formation,suggesting a role of oxidative stress in bone loss,while the role of OPG/RANKL imbalance in bone metabolism in OSAHS needs further evaluation .
基金This work was supported by the grants from Jiangsu Province Key Medical Center (No. ZX200608), the National Nature Science Foundation of China (No. 30672140, No. 81071451), the Colleges and Universities Natural Science Foundation in Jiangsu Province (No. 10KJB320019), the Key Project Surpported by the Medical Science and Technology Department Foundation, Jiangsu Province, Department of Health (No. H201012) and the Social Development Projects in Suzhou (No. SS08020).
文摘Background The cannabinoid receptor-2 (CB2) is important for bone remodeling. In this study, we investigated the effects of CB2 selective antagonist (AM630) on receptor activator of nuclear factor kappa B (RANK) ligand (RANKL)induced osteoclast differentiation and the underlying signaling pathway using a monocyte-macrophage cell line-RAW264.7.Methods RAW264.7 was cultured with RANKL for 6 days and then treated with AM630 for 24 hours. Mature osteoclasts were measured by tartrate-resistant acid phosphatase (TRAP) staining using a commercial kit. Total ribonucleic acid (RNA)was isolated and real-time reverse transcriptase-polymerase chain reaction (RT-PCR) was done to examine the expression of RANK, cathepsin K (CPK) and nuclear factor kappa B (NF-κB). The extracellular signal-regulated kinase (ERK),phosphorylation of ERK (P-ERK) and NF-κB production were tested by Western blotting. The effect of AM630 on RAW264.7 viability was determined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide (MTT) assay.Results AM630 did not affect the viability of RAW264.7. However, this CB2 selective antagonist markedly inhibited osteoclast formation and the inhibition rate was dose-dependent. The dose of 〉100 nmol/L could reduce TRAP positive cells to the levels that were significantly lower than the control. AM630 suppressed the expression of genes associated with osteoclast differentiation and activation, such as RANK and CPK. An analysis of a signaling pathway showed that AM630 inhibited the RANKL-induced activation of ERK, but not NF-κB.Conclusion AM630 could inhibit the osteoclastogenesis from RAW264.7 induced with RANKL.
文摘Background Receptor activator of nuclear factor kappa B (NF-κB) ligand (RANKL) and osteoprotegerin (OPG) have been recently shown to play important roles in bone resorption. The aim of this study was to investigate the possible association between the expression of bone resorption regulators (RANKL and OPG) and inflammatory cell infiltration in chronic apical periodontitis.Methods The samples of chronic periapical lesions (n=40) and healthy periapical tissues (n=10) were examined for immunohistochemical analysis of RANKL and OPG. Lesion samples were further analyzed for the inflammatory infiltration condition. The inflammatory cell infiltration was scored in relation to immunohistochemical reactivity for CD3, CD20 and CD68.Results The number of RANKL-positive cells and the ratio of RANKL/OPG in chronic apical periodontitis were significantly higher than those in healthy periapical tissues (P<0.001). The number of RANKL-positive cells was higher in lesions with severe inflammatory infiltration than in those with light inflammatory infiltration (P<0.05). Significantly increased RANKL expression was found with T lymphocytes (CD3+), macrophages (CD68+) and B lymphocytes (CD20+)infiltration (P<0.05). No association was found between the ratio of RANKL/OPG and inflammatory cell infiltration.Conclusions RANKL expression was increased with T, B lymphocytes and macrophages infiltration, respectively in chronic periapical lesions. RANKL appears to be closely related to periapical inflammatory infiltrates. The relative ratio of RANKL/OPG may be a key determinant of RANKL-mediated bone resorption.
基金Supported by the Zhejiang Provincial Natural Science Foundation of China(No.LY12H29008)the Zhejiang Provincial Project of Traditional Chinese Medicine Science and Technology Plan(No.2008CA086,2009CB195,2012ZB121,2015ZA143)+1 种基金the Hangzhou Health Science and Technology Plan(No.2010B027,No.2014A37)the Hangzhou Social Development Plan(No.20120633B12,No.20160533B45)
文摘Objective: To study the effect of Wenhua Juanbi Recipe(温化蠲痹方, WJR) on expression of receptor activator of nuclear factor kappa B ligand(RANKL), osteoprotegerin(OPG), and tumor necrosis factor receptor superfamily member 14(TNFRSF14, also known as LIGHT) in rats with collagen-induced arthritis(CIA). Methods: CIA rats were generated by subcutaneous injection of bovine collagen type-Ⅱ at the tail base. Sixty CIA rats were randomly assigned(10 animals/group) to: model, methotrexate(MTX)-treated(0.78 mg/kg body weight), and WJR-treated(22.9 g/kg) groups. Healthy normal rats(n=10) were used as the normal control. Treatments or saline were administered once daily by oral gavage. Rats were sacrificed at day 28 post-treatment and knee synovium and peripheral blood serum were collected. Toe swelling degree and expression of RANKL, OPG, and LIGHT were determined by Western blot and immunohistochemistry. Results: Compared with the normal group, toe swelling degree was significantly increased in the model group(P〈0.01). After treatment, toe swelling degree decreased significantly in the WJR and MTX groups compared with the model group(P〈0.01). Compared with the normal group, expression of RANKL and LIGHT were significantly increased and OPG significantly decreased in peripheral blood and synovium of the model group(P〈0.01). Conversely, RANKL and LIGHT expression were significantly reduced and OPG increased in the WJR and MTX groups compared with the model group(P〈0.01). No statistically significant difference existed between WJR and MTX groups. Conclusion: WJR likely acts by reducing RANKL expression and increasing OPG expression, thus inhibiting RANKL/RANK interaction and reducing LIGHT expression, thereby inhibiting osteoclast formation/activation to block bone erosion.
文摘Background Pancreatic beta-cell apoptosis induced by lipotoxicity, to a large extent, contributes to the progression of type 2 diabetes. To investigate the mechanism of free fatty acid induced apoptosis, we aimed to study the effects of palmitic acid (PA) on the apoptosis and peroxisome proliferator-activated receptor y coactivator-1α (PGC-1α) expression in βTC3 cells as well as the possible role of nuclear factor-KB (NF-KB) in this process. Methods Hoechst 33258 was used to detect βTC3 cell apoptosis, which was induced by PA stimulation for 12 hours. PGC-1α expression was analyzed by reverse transcription polymerase chain reaction, IκB kinase β (IKKβ), IκBα NF-KB-inducing kinase (NIK) and ReI-B expressions were analyzed by Western blotting. MGβ2 was employed to block the endogenous IκBαdegradation before PA administration, and then its effect on PA-inducing cell apoptosis and PGC-1α mRNA expression was analyzed. Results Significant increased cell apoptosis was found at the concentration of 0.5 mmol/L and 1.0 mmol/L PA administration. PA (0.5 mmol/L) could extensively reduced the expression of PGC-1α mRNA. After exposing βTC3 cells to 0.5 mmol/L PA for different time periods (0, 4, 6, 8, 10 and 12 hours), IKKβ protein expression increased while IκBα NIK and ReI-B protein expression declined in a time-dependent manner. Pretreatment with MGβ2 to inhibit the degradation of IκBα partially prevented the down-regulation of PGC-1α mRNA expression after 12-hour PA treatment in accordance with the decrease of PA induced apoptosis. Conclusions NF-KB canonical pathway was activated in PA-mediated βTC3 cell apoptosis, whereas non-canonical pathway was inhibited. Reduced PGC-1α expression by PA in βTC3 cells could involve the activation of canonical NF-KB pathway, so as to deteriorate the PA induced apoptosis.