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1.
Mol Ther ; 32(5): 1479-1496, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38429926

RESUMO

Intense inflammatory response impairs bone marrow mesenchymal stem cell (BMSC)-mediated bone regeneration, with transforming growth factor (TGF)-ß1 being the most highly expressed cytokine. However, how to find effective and safe means to improve bone formation impaired by excessive TGF-ß1 remains unclear. In this study, we found that the expression of orphan nuclear receptor Nr4a1, an endogenous repressor of TGF-ß1, was suppressed directly by TGF-ß1-induced Smad3 and indirectly by Hdac4, respectively. Importantly, Nr4a1 overexpression promoted BMSC osteogenesis and reversed TGF-ß1-mediated osteogenic inhibition and pro-fibrotic effects. Transcriptomic and histologic analyses confirmed that upregulation of Nr4a1 increased the transcription of Wnt family member 4 (Wnt4) and activated Wnt pathway. Mechanistically, Nr4a1 bound to the promoter of Wnt4 and regulated its expression, thereby enhancing the osteogenic capacity of BMSCs. Moreover, treatment with Nr4a1 gene therapy or Nr4a1 agonist Csn-B could promote ectopic bone formation, defect repair, and fracture healing. Finally, we demonstrated the correlation of NR4A1 with osteogenesis and the activation of the WNT4/ß-catenin pathway in human BMSCs and fracture samples. Taken together, these findings uncover the critical role of Nr4a1 in bone formation and alleviation of inflammation-induced bone regeneration disorders, and suggest that Nr4a1 has the potential to be a therapeutic target for accelerating bone healing.


Assuntos
Regeneração Óssea , Inflamação , Células-Tronco Mesenquimais , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares , Osteogênese , Proteína Wnt4 , Células-Tronco Mesenquimais/metabolismo , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/genética , Osteogênese/genética , Regeneração Óssea/genética , Animais , Camundongos , Proteína Wnt4/metabolismo , Proteína Wnt4/genética , Humanos , Inflamação/genética , Inflamação/metabolismo , Regulação da Expressão Gênica , Fator de Crescimento Transformador beta1/metabolismo , Fator de Crescimento Transformador beta1/genética , Via de Sinalização Wnt , Masculino , Transcrição Gênica , Histona Desacetilases/metabolismo , Histona Desacetilases/genética , Modelos Animais de Doenças
2.
BMC Cancer ; 19(1): 949, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31615459

RESUMO

BACKGROUND: In the quest for new anti-cancer drugs, the drug discovery process has shifted to screening of active ingredients in traditional eastern medicine. Matrine is an active alkaloid isolated from plants of the Sophora genus used in traditional Chinese herbal medicine that exhibits a wide spectrum of biological properties and has a potential as an anti-proliferative agent. In this study, we investigated the anticancer property of MASM, ([(6aS, 10S, 11aR, 11bR, 11cS)210-Methylamino-dodecahydro-3a, 7a-diaza-benzo (de)anthracene-8-thione]), a potent derivative of matrine. METHODS: Four epithelial cancer cell lines representing the dominant cancers, namely: A549 (non-small-cell lung cancer cell line), MCF-7 and MDA-MB-231 (breast cancer cell lines), and Hela (cervical cancer cell line) were employed, and the mechanistic underpinning of MASM-induced apoptosis was investigated using flow cytometry, western blot and immunofluorescence. RESULTS: MASM, induced apoptosis via caspase 3 dependent and independent pathways, and autophagy in all the four cancer cell lines, but post-EMT (epithelial mesenchymal transition) cells showed greater sensitivity to MASM. Scavenging reactive oxygen species using N-acetylcysteine rescued all cancer cell lines from apoptosis and autophagy. Mechanistic analysis revealed that MASM induced autophagy involves inhibition of Akt signaling and the activation of Erk and p38 signaling, and inhibition of autophagy further enhanced the apoptosis induced by MASM. CONCLUSIONS: These results indicate that MASM possesses potency against cancer cells and modulating autophagy during MASM administration could be used to further enhance its therapeutic effects.


Assuntos
Alcaloides/farmacologia , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Sistema de Sinalização das MAP Quinases , Neoplasias/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Quinolizinas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Células A549 , Alcaloides/química , Antineoplásicos/química , Sobrevivência Celular/efeitos dos fármacos , Descoberta de Drogas/métodos , Medicamentos de Ervas Chinesas/química , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Células HeLa , Humanos , Células MCF-7 , Neoplasias/patologia , Quinolizinas/química , Transdução de Sinais/efeitos dos fármacos , Sophora/química , Matrinas
4.
Arch Orthop Trauma Surg ; 138(10): 1433-1441, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29869690

RESUMO

PURPOSE: To cross-culturally adapt and validate the International Knee Documentation Committee Subjective Knee Form to Simplified Chinese (SC-IKDC-SKF). METHODS: The original version was translated and cross-culturally adapted into Simplified Chinese according to standard guidelines. A total of 103 patients enrolled in our research. Each participant was asked to complete three instruments including the SC-IKDC-SKF, the Lysholm knee score, and the Short Form-36 (SF-36). Each participant was asked to complete the SC-IKDC-SKF twice with an interval of 7 days. A portion of the participants (n = 51) finished the SC-IKDC-SKF a third time with an interval of 12 months after arthroscopic treatment. Psychometric assessments included internal consistency, test-retest reliability, content and construct validity, and responsiveness. RESULTS: Strong internal consistency was proved with Cronbach's α = 0.92. The intraclass correlation coefficient reached 0.94, indicating high test-retest reliability. No ceiling or floor effect was observed. Compared with the Lysholm knee score and the subscales of SF-36, good convergent and divergent validity of the SC-IKDC-SKF were demonstrated. The standard response mean was 2.39 and the effect size was 1.33, indicating high responsiveness. CONCLUSIONS: The SC-IKDC-SKF was demonstrated to be a reliable, valid and responsive instrument for evaluating knee functions and symptoms of patients with knee pathology in mainland China. LEVEL OF EVIDENCE: II.


Assuntos
Artropatias/diagnóstico , Traumatismos do Joelho/diagnóstico , Articulação do Joelho/cirurgia , Joelho/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Artroscopia , Povo Asiático , China , Comparação Transcultural , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados da Assistência ao Paciente , Psicometria , Reprodutibilidade dos Testes , Inquéritos e Questionários , Traduções , Adulto Jovem
5.
J Arthroplasty ; 31(7): 1504-9, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27006146

RESUMO

BACKGROUND: This study was conducted to compare the blood loss during primary total hip arthroplasty (THA) between ankylosing spondylitis (AS) and hip osteoarthritis (OA). METHODS: We reviewed 120 THAs in 68 patients comprising 3 groups: AS with total bony ankylosis of the hips (ASB), AS with stiff hips (ASS), and OA. Demographics, perioperative laboratory values, intraoperative data, blood loss, transfusion rate, transfusion reactions, surgical complications, hospitalization cost, and length of stay (LOS) were collected and analyzed among ASB, ASS, and OA groups. RESULTS: The patients of the ASB and ASS groups were much younger and thinner than those of the OA group. There were no significant differences in the preoperative values of activated partial thromboplastin time, prothrombin time, and international normalized ratio among the 3 groups (all P > .05). The intraoperative blood loss, volume of drainage, hidden blood loss, transfusion rate, transfusion reactions, and hospitalization cost in the ASB group were significantly higher than in the other 2 groups, although not significantly different between the ASS and OA groups (P > .05). CONCLUSION: Both AS and OA can cause hyperosteogeny to the hips, but ASB patients have more serious symptoms in their affected hips. This may cause more blood loss in THA surgery because of bone surface bleeding. The reason that ASB patients suffered more blood loss may be related to the high difficulty and long duration of the operation.


Assuntos
Artroplastia de Quadril , Perda Sanguínea Cirúrgica , Osteoartrite do Quadril/cirurgia , Espondilite Anquilosante/cirurgia , Adolescente , Adulto , Idoso , Transfusão de Sangue , Feminino , Articulação do Quadril/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
6.
J Orthop Sci ; 20(1): 55-63, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25270018

RESUMO

OBJECTIVE: The objective is to integrate all the eligible studies and investigate whether the programmed cell death 1 (PDCD-1) gene polymorphisms (PD 1.3 G/A, PD 1.5 C/T, and PD 1.9 C/T polymorphism) are correlated with ankylosing spondylitis risk (AS). Ankylosing spondylitis is a chronic inflammatory disease, and several genetic and environmental factors play an important role in the development and progression of AS. Significant associations between PDCD-1 gene polymorphisms (PD 1.3 G/A, PD 1.5 C/T or PD 1.9 C/T) and AS risk have been reported; however, some of these results are controversial. METHODS: A systematic online search was performed using PubMed, EMBASE, Web of Science, and the Cochrane Library to identify case-control studies investigating the relationship between PD 1.3 G/A, PD 1.5 C/T, and PD 1.9 C/T polymorphisms and the susceptibility of AS. The pooled odds ratio (OR) with 95 % confidence interval (CI; 95 %) was calculated to assess the associations, and subgroup meta-analyses were performed according to the ethnicity of the study populations. RESULTS: Five studies involving 909 cases and 982 controls met the inclusion criteria after assessment by two reviewers. Overall, there were no significant associations between PD 1.3 G/A and PD 1.5 C/T polymorphisms and AS risk. With regard to PD 1.9 C/T polymorphism, a significant association was found under the allele contrast model (T vs. C: OR 1.74, 95 % CI 1.48-2.06, P < 0.001), heterozygote model (CT vs. CC: OR 2.43, 95 % CI 1.65-3.59, P < 0.001), homozygote model (TT vs. CC: OR 1.87, 95 % CI 1.30-2.71, P = 0.001), and dominant model (CT/TT vs. CC: OR 2.29, 95 % CI 1.65-3.18, P < 0.001). In the subgroup analysis of ethnicity, no significant associations were found between PD 1.3 G/A, PD 1.5 C/T polymorphisms, and AS risk in either Asian or Caucasian populations. However, our study suggested that PD 1.9 C/T polymorphism was significantly associated with AS in Asian populations (T vs. C: OR 1.72, 95 % CI 1.46-2.04, P < 0.001; CT vs. CC: OR 2.44, 95 % CI 1.56-3.82, P < 0.001; TT vs. CC: OR 1.88, 95 % CI 1.30-2.73, P = 0.001; and CT/TT vs. CC: OR 2.29, 95 % CI 1.58-3.32, P < 0.001) but not in Caucasian populations. CONCLUSION: The PD 1.9 C/T polymorphism may be involved in susceptibility to AS, particular in Asian populations; however, no significant associations were found between PD 1.3 G/A, PD 1.5 C/T polymorphisms, and AS risk in either Asians or Caucasians.


Assuntos
Predisposição Genética para Doença/genética , Polimorfismo Genético/genética , Receptor de Morte Celular Programada 1/genética , Espondilite Anquilosante/genética , Humanos
7.
J Orthop Translat ; 44: 35-46, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38235367

RESUMO

Objective: Osteoarthritis (OA), which involves total joint damage and dysfunction, is a leading cause of disability worldwide. However, its exact pathogenesis remains unclear. Here, we identified TCF12 as an important regulator of the progression of OA. Methods: qRT-PCR, immunoblotting and immunohistochemistry (IHC) were used to detect the expression level of TCF12. The interaction of TCF12 with its downstream factor CXCR4 was assessed by Western blotting, immunofluorescence, qRT-PCR and luciferase assays. A mouse model was generated to examine the functions and mechanism of TCF12 in vivo. Result: TCF12 expression was upregulated in chondrocytes stimulated with IL-1ß and osteoarthritic chondrocytes. TCF12 upregulates the expression of CXCR4 and leads to dysfunction of the TGF-ß signaling pathway. Furthermore, knockdown of TCF12 alleviated cartilage damage in a mouse model generated by destabilization of the medial meniscus (DMM). Conclusion: TCF12 aggravates the progression of OA by targeting CXCR4 and then activating the TGF-ß signaling pathway, suggesting that TCF12 may be a new target for the treatment of OA. The translational potential of this article: Transcription Factor 12(TCF12), is known to regulate cell development and differentiation, It has been widely studied in various organs and diseases, but its role in OA remains unclear. Here, we identified Transcription Factor 12(TCF12) as an important regulator mediating chondrocyte senescence and cartilage extracellular matrix degradation indicating its role in OA. We found that TCF12 expression was upregulated both locally and systemically as OA advanced in patients with OA, and in mice after DMM surgery to induce OA. TCF12 expression caused striking progressive articular cartilage damage, synovial hyperplasia in OA mice, and remarkably, it was relieved by intra-articular administration of mutant mouse TCF12 lentiviral vector (shTCF12). Furthermore, TCF12 upregulated the expression of CXCR4, leading to exacerbation of experimental OA partially through activation of TGF-ß signaling in chondrocytes. TCF12 expression was upregulated in chondrocytes treated with IL-1ß and osteoarthritic chondrocytes. Our findings established an essential role of TCF12 in chondrocyte senescence and cartilage extracellular matrix degradation during OA, and identified intra-articular injection of TCF12 as a potential therapeutic strategy for OA prevention and treatment.

8.
Medicine (Baltimore) ; 96(35): e7805, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28858091

RESUMO

BACKGROUND: Several studies investigated the relationship between programmed cell death 1 (PDCD1) gene polymorphisms and rheumatoid arthritis (RA) risk, but the results were controversial. To explore whether PDCD1 gene polymorphisms have an effect on RA risk, we conducted this meta-analysis to investigate the relationships between PDCD1 polymorphisms (rs36084323 [PD-1.1 G/A], rs11568821 [PD-1.3 G/A] and rs2227981 [PD-1.5 C/T]) and RA risk under 4 genetic models. METHODS: PubMed, EMBASE, Web of Science, Cochrane Library China National Knowledge Infrastructure (CNKI), and Chinese Biomedical Literature Database (CBLM) were systematically searched for all eligible case-control studies. The last search was updated on September 10, 2016. Studies were accessed using Newcastle-Ottawa Scale case control study (NOS), and the combined effect size was calculated using STATA software, version 12.0. The pooled odds ratio (OR) with 95% confidence interval (CI) was calculated to assess the association. Heterogeneity analysis and subgroup analysis were also performed. Sensitivity analysis and publication bias were also performed if necessary. RESULTS: This meta-analysis included 6 studies. The result demonstrated null association between rs36084323 (PD-1.1 G/A) polymorphism and RA susceptibility in all 4 genetic models. With regard to rs11568821 (PD-1.3 G/A), statistically significant association with RA risk was observed under allele model in Caucasians (allele model A vs G, OR = 1.19, 95% CI = 1.03-1.41). There was no significant association between rs2227981 (PD-1.5 C/T) polymorphism and RA risk. CONCLUSION: The present study suggests that mutant A allele in rs11568821 (PD-1.3 G/A) might increase the susceptibility to RA in Caucasians.


Assuntos
Artrite Reumatoide/genética , Predisposição Genética para Doença , Receptor de Morte Celular Programada 1/genética , Humanos , Polimorfismo de Nucleotídeo Único
9.
BMC Pharmacol Toxicol ; 18(1): 58, 2017 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-28738843

RESUMO

BACKGROUND: With the re-popularity of metal-on-metal (MoM) bearing in recent years, the cobalt toxicity has been a cause for concern in the total hip replacement surgery by both physicians and patients. METHODS: MG-63 cell line was cultured in vitro and incubated with cobalt (II) chloride (CoCl2) and/or with astaxanthin (ASX) for 24 h. MTT assay was conducted to evaluate the cell viability after cobalt exposure and ASX treatment. Fluorescence-activated cell sorting (FACS) analysis was performed to examine the reactive oxygen species (ROS) level. Quantitative real-time polymerase chain reaction (PCR) was adopted to determine the mRNA levels of related targets. And western blot analysis was used to examine the protein expressions. One-way ANOVA with posttest Newman-Keuls multiple comparisons was adopted to analysis all the obtained data. RESULTS: In the current study, ASX exhibited significant protective effect against the Co(II)-induced cytotoxicity in MG-63 cell line. We also found that ASX protected the cells against Co-induced apoptosis by regulating the expression of Bcl-2 family proteins. Besides, heme oxygenase 1 (HO-1) could be activated by Co exposure; ASX treatment significantly inhibited HO-1 activation, suppressing the oxidative stress induced by Co exposure. Moreover, c-Jun N-terminal Kinase (JNK) phosphorylation was shown to participate in the signaling pathway of the protective effect of ASX. However, knockdown of JNK expression by siRNA transfection or JNK inhibitor SP600125 treatment did not affect the protective effect of ASX against cobalt cytotoxicity in MG-63 cells. CONCLUSIONS: ASX mitigated cobalt cytotoxicity in the MG-63 cells by modulating the oxidative stress. And ASX could be a promising therapy against cobalt toxicity in the hip articulation surgery.


Assuntos
Cobalto/toxicidade , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Humanos , MAP Quinase Quinase 4/metabolismo , NF-kappa B/genética , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Fator de Necrose Tumoral alfa/genética , Xantofilas/farmacologia
10.
Mol Med Rep ; 15(4): 1943-1951, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28259985

RESUMO

The study of ankylosing spondylitis (AS) has made significant progress over the last decade. Genome-wide association studies have identified and further substantiated the role of susceptibility genes outside the major histocompatibility complex locus. However, human leukocyte antigen (HLA)­B27 has been suggested to be important in the pathogenesis of AS, contributing to ~20.1% of AS heritability. The current review will present the classical and non­classical forms of HLA-B27, as well as their pathogenic roles, and further discuss the hypotheses regarding the potential pathogenesis of AS. In addition, the association between the pathogenic role of HLA­B27 and inflammatory indexes, including the interleukin-23/­17 axis will be investigated to provide novel insights into the pathogenesis of AS. The aim of the present review is to provide an update of the current research into the pathogenesis of AS, and provide a comprehensive description of the pathogenic role of HLA-B27 in AS.


Assuntos
Antígeno HLA-B27/análise , Espondilite Anquilosante/patologia , Animais , Antígeno HLA-B27/imunologia , Humanos , Dobramento de Proteína , Multimerização Proteica , Deficiências na Proteostase/imunologia , Deficiências na Proteostase/patologia , Espondilite Anquilosante/imunologia
11.
Sci Rep ; 7(1): 2454, 2017 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-28550307

RESUMO

MASM is a matrine derivate that exhibits a number of pharmacological effects, including immunosuppressive activity and anti-inflammatory properties. In this study, the mechanisms underlying the therapeutic efficacy of MASM in the treatment of rheumatoid arthritis were investigated using DBA/1 mice with collagen-induced arthritis (CIA) and fibroblast-like synoviocytes derived from rheumatoid arthritis patients (RA-FLS). We demonstrated that MASM markedly attenuated the severity of arthritis in CIA mice. The therapeutic effects were associated with ameliorated joint swelling and reduced bone erosion and destruction. Furthermore, the administration of MASM suppressed the expression of pro-inflammatory cytokines (TNF-α, IL-1ß, IL-6). In vitro, MASM inhibited the expression of pro-inflammatory cytokines (TNF-α, IL-6, IL-8) and matrix metalloproteinases (MMP-1, MMP-3 and MMP-13) by inhibiting both the phosphorylation of MAPKs and the activation of NF-κB in IL-1ß-stimulated RA-FLS. Additionally, MASM could induce apoptosis of RA-FLS via mitochondrial and Akt signaling pathways in human RA-FLS. These findings suggest that MASM could attenuate arthritis severity in CIA mice at least partially by blocking the phosphorylation of MAPKs and the activation of NF-κB and by inducing apoptosis in RA-FLS. MASM could be a potent therapeutic agent for the treatment of RA.


Assuntos
Alcaloides/farmacologia , Artrite Experimental/prevenção & controle , Fibroblastos/efeitos dos fármacos , Quinolizinas/farmacologia , Sinoviócitos/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Artrite Experimental/genética , Artrite Experimental/metabolismo , Artrite Reumatoide/metabolismo , Artrite Reumatoide/patologia , Citocinas/sangue , Citocinas/metabolismo , Fibroblastos/metabolismo , Fibroblastos/patologia , Humanos , Mediadores da Inflamação/sangue , Mediadores da Inflamação/metabolismo , Masculino , Camundongos Endogâmicos DBA , Transdução de Sinais/efeitos dos fármacos , Membrana Sinovial/metabolismo , Membrana Sinovial/patologia , Sinoviócitos/metabolismo , Sinoviócitos/patologia , Matrinas
12.
BMJ Open ; 6(9): e011605, 2016 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-27638493

RESUMO

OBJECTIVES: Orthopaedics-related diseases and conditions are a significant burden worldwide. In this study, we aimed to compare the quantity and quality of research output in the field of orthopaedics from Mainland China (MC), USA, UK, Japan and Germany. SETTING: The USA, UK, Japan, Germany and MC. PARTICIPANTS: We selected orthopaedics journals from the subject category 'orthopedics' from the Science Citation Index Expanded (SCIE). OUTCOME MEASURES: The number of publications, the number of publications in the surveyed publication types, impact factor (IF) and citations from the corresponding country from 2005 to 2014 were collected for quantity and quality comparisons. RESULTS: A total of 128 895 articles were published worldwide in orthopaedics-related journals from 2005 to 2014. The USA contributed the largest proportion (31 190 (24.20%)), followed by the UK (6703 (5.20%)), Japan (5718 (4.41%)), Germany (4701 (3.66%)) and MC (3389 (2.63%)). Publications from MC represented the fewest, but this quantity is rapidly increasing. The quantity of annual publications from MC has exceeded that of Germany since 2012. The USA plays a predominant role in all kinds of publication types under investigation in the study, except in the category of meta-analysis. MC was in the last place for cumulative IFs, and the average IF actually decreased from the beginning of the study. For total and average citations, MC still lags behind the other countries in the study. CONCLUSIONS: The USA has occupied the dominant place in orthopaedics-related research for the last 10 years. Although MC has made great progress in the number of published works in the field of orthopaedics over the last 10 years, the quality of these publishing efforts needs further improvement.


Assuntos
Procedimentos Ortopédicos/estatística & dados numéricos , Ortopedia , Publicações , Bibliometria , Pesquisa Biomédica , China , Estudos Clínicos como Assunto , Alemanha , Pesquisas sobre Atenção à Saúde , Humanos , Japão , Fator de Impacto de Revistas , Reino Unido , Estados Unidos
13.
Int J Clin Exp Pathol ; 8(10): 13695-706, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26722597

RESUMO

Apoptosis of osteoblasts caused by glucocorticoids has been identified as an important contributor to the development of osteoporosis. Tanshinone IIA (Tan), an active ingredient extracted from the rhizome of the Salvia miltiorrhiza Bunge (Danshen), has been reported to cast positive effects on osteoporosis. However, the precise mechanisms accounting this action remain elusive. In this study, by using osteoblastic MC3T3-E1 cells as a model, we confirmed the protective effects of Tan against dexamethasone (Dex)-induced cell apoptosis and further clarified its molecular mechanism of action. Our results showed that treatment with Dex caused cell injury, increased cytosol cytochrome c level and Nox expression, induced apoptosis in caspase-9-dependent manner, and enhanced reactive oxygen species (ROS) production. Tan attenuated these deleterious consequence triggered by Dex. Moreover, Dex-induced ROS production and cell injury were inhibited by antioxidant, NADPH oxidases inhibitors, Nox4 inhibitor, and Nox4 small interfering RNA (siRNA). Overexpression of Nox4 almost abolished the inhibitory effect of Tan on Dex-induced cell injury and apoptosis. The results also demonstrated significant involvement of Nox4 in the Dex-induced apoptosis. Nox4-derived ROS led to apoptosis through activation of intrinsic mitochondrial pathway. Additionally, we evidenced that Tan reversed Dex-induced apoptosis via inactivation of Nox4. The present findings suggest that inhibition of Nox4 may be a novel therapeutic approach of Tan to prevent against glucocorticoids-induced osteoblasts apoptosis and osteoporosis.


Assuntos
Abietanos/farmacologia , Apoptose/efeitos dos fármacos , Dexametasona/efeitos adversos , Glucocorticoides/efeitos adversos , Osteoporose/prevenção & controle , Células 3T3 , Animais , Antioxidantes/farmacologia , Caspase 9/genética , Caspase 9/metabolismo , Humanos , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , NADPH Oxidase 4 , NADPH Oxidases/antagonistas & inibidores , NADPH Oxidases/genética , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , RNA Interferente Pequeno , Espécies Reativas de Oxigênio/metabolismo
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