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1.
Adv Sci (Weinh) ; 11(12): e2303981, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38224203

RESUMO

Coloading adjuvant drugs or biomacromolecules with photosensitizers into nanoparticles to enhance the efficiency of photodynamic therapy (PDT) is a common strategy. However, it is difficult to load positively charged photosensitizers and negatively charged adjuvants into the same nanomaterial and further regulate drug release simultaneously. Herein, a single-component dual-functional prodrug strategy is reported for tumor treatment specifically activated by tumor microenvironment (TME)-generated HOCl. A representative prodrug (DHU-CBA2) is constructed using indomethacin grafted with methylene blue (MB). DHU-CBA2 exhibited high sensitivity toward HOCl and achieved simultaneous release of dual drugs in vitro and in vivo. DHU-CBA2 shows effective antitumor activity against lung cancer and spinal metastases via PDT and cyclooxygenase-2 (COX-2) inhibition. Mechanistically, PDT induces immunogenic cell death but stimulates the gene encoding COX-2. Downstream prostaglandins E2 and Indoleamine 2,3 dioxygenase 1 (IDO1) mediate immune escape in the TME, which is rescued by the simultaneous release of indomethacin. DHU-CBA2 promotes infiltration and function of CD8+ T cells, thus inducing a robust antitumor immune response. This work provides an autoboost strategy for a single-component dual-functional prodrug activated by TME-specific HOCl, thereby achieving favorable tumor treatment via the synergistic therapy of PDT and a COX-2 inhibitor.


Assuntos
Neoplasias Pulmonares , Fotoquimioterapia , Pró-Fármacos , Neoplasias da Coluna Vertebral , Humanos , Fármacos Fotossensibilizantes/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Ciclo-Oxigenase 2 , Linfócitos T CD8-Positivos , Neoplasias da Coluna Vertebral/tratamento farmacológico , Indometacina , Microambiente Tumoral
2.
Adv Healthc Mater ; 13(4): e2302342, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37975509

RESUMO

Intercellular communication between tumor cells and immune cells regulates tumor progression including positive communication with immune activation and negative communication with immune escape. An increasing number of methods are employed to suppress the dominant negative communication in tumors such as PD-L1/PD-1. However, how to effectively improve positive communication is still a challenge. In this study, a nuclear-targeted photodynamic nanostrategy is developed to establish positive spatiotemporal communication, further activating dual antitumor immunity, namely innate and adaptative immunity. The mSiO2 -Ion@Ce6-NLS nanoparticles (NPs) are designed, whose surface is modified by ionic liquid silicon (Ion) and nuclear localization signal peptide (NLS: PKKKRKV), and their pores are loaded with the photosensitizer hydrogen chloride e6 (Ce6). Ion-modified NPs enhance intratumoral enrichment, and NLS-modified NPs exhibit nuclear-targeted characteristics to achieve nuclear-targeted photodynamic therapy (nPDT). mSiO2 -Ion@Ce6-NLS with nPDT facilitate the release of damaged double-stranded DNA from tumor cells to activate macrophages via stimulator of interferon gene signaling and induce the immunogenic cell death of tumor cells to activate dendritic cells via "eat me" signals, ultimately leading to the recruitment of CD8+ T-cells. This therapy effectively strengthens positive communication to reshape the dual antitumor immune microenvironment, further inducing long-term immune memory, and eventually inhibiting tumor growth and recurrence.


Assuntos
Nanopartículas , Fotoquimioterapia , Linhagem Celular Tumoral , Linfócitos T CD8-Positivos , Fármacos Fotossensibilizantes/farmacologia , Fotoquimioterapia/métodos , Macrófagos , Imunoterapia/métodos , Microambiente Tumoral
3.
ACS Nano ; 17(21): 21153-21169, 2023 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-37921421

RESUMO

Innate and adaptive immunity is important for initiating and maintaining immune function. The nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome serves as a checkpoint in innate and adaptive immunity, promoting the secretion of pro-inflammatory cytokines and gasdermin D-mediated pyroptosis. As a highly inflammatory form of cell death distinct from apoptosis, pyroptosis can trigger immunogenic cell death and promote systemic immune responses in solid tumors. Previous studies proposed that NLRP3 was activated by translocation to the mitochondria. However, a recent authoritative study has challenged this model and proved that the Golgi apparatus might be a prerequisite for the activation of NLRP3. In this study, we first developed a Golgi apparatus-targeted photodynamic strategy to induce the activation of NLRP3 by precisely locating organelles. We found that Golgi apparatus-targeted photodynamic therapy could significantly upregulate NLRP3 expression to promote the subsequent release of intracellular proinflammatory contents such as IL-1ß or IL-18, creating an inflammatory storm to enhance innate immunity. Moreover, this acute NLRP3 upregulation also activated its downstream classical caspase-1-dependent pyroptosis to enhance tumor immunogenicity, triggering adaptive immunity. Pyroptosis eventually led to immunogenic cell death, promoted the maturation of dendritic cells, and effectively activated antitumor immunity and long-lived immune memory. Overall, this Golgi apparatus-targeted strategy provided molecular insights into the occurrence of immunogenic pyroptosis and offered a platform to remodel the tumor microenvironment.


Assuntos
Proteína 3 que Contém Domínio de Pirina da Família NLR , Piroptose , Inflamassomos/metabolismo , Imunidade Inata , Complexo de Golgi/metabolismo , Interleucina-1beta , Caspase 1/metabolismo
4.
Mater Today Bio ; 19: 100547, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36896415

RESUMO

Circadian rhythm (CR) disruption contributes to tumor initiation and progression, however the pharmacological targeting of circadian regulators reversely inhibits tumor growth. Precisely controlling CR in tumor cells is urgently required to investigate the exact role of CR interruption in tumor therapy. Herein, based on KL001, a small molecule that specifically interacts with the clock gene cryptochrome (CRY) functioning at disruption of CR, we fabricated a hollow MnO2 nanocapsule carrying KL001 and photosensitizer BODIPY with the modification of alendronate (ALD) on the surface (H-MnSiO/K&B-ALD) for osteosarcoma (OS) targeting. The H-MnSiO/K&B-ALD nanoparticles reduced the CR amplitude in OS cells without affecting cell proliferation. Furthermore, nanoparticles-controlled oxygen consumption by inhibiting mitochondrial respiration via CR disruption, thus partially overcoming the hypoxia limitation for photodynamic therapy (PDT) and significantly promoting PDT efficacy. An orthotopic OS model demonstrated that KL001 significantly enhanced the inhibitory effect of H-MnSiO/K&B-ALD nanoparticles on tumor growth after laser irradiation. CR disruption and oxygen level enhancement induced by H-MnSiO/K&B-ALD nanoparticles under laser irradiation were also confirmed in vivo. This discovery first demonstrated the potential of CR controlling for tumor PDT ablation and provided a promising strategy for overcoming tumor hypoxia.

5.
J Orthop Res ; 41(7): 1555-1564, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36448180

RESUMO

Oxidative stress can lead to nucleus pulposus cell (NPC) apoptosis, which is considered to be one of the main contributors to intervertebral disc degeneration (IVDD). Procyanidin B2 is a natural antioxidant that protects against oxidative stress. However, whether procyanidin B2 protects NPCs from oxidative stress remains unknown. In this study, we demonstrated that procyanidin B2 could reduce tert-butyl hydroperoxide-induced reactive oxygen species in rat NPCs and attenuate rat NPC apoptosis. Further experiments revealed that procyanidin B2 upregulated the expression of both nuclear factor erythroid 2-related factor 2 (Nrf2) and phosphorylation of protein kinase B (Akt). We then used silencing of Nrf2 and LY294002 to silence Nrf2 expression and block the phosphatidylinositol 3-kinase (PI3K)/Akt pathway, respectively, and found that the protective roles of procyanidin B2 in NPCs were inhibited. Therefore, we demonstrated that procyanidin B2 alleviated rat NPC apoptosis induced by oxidative stress by upregulating Nrf2 via activation of the PI3K/Akt signaling pathway. This study provides a potential therapeutic approach for procyanidin B2 in IVDD, which might help in the development of new drugs for IVDD treatment.


Assuntos
Degeneração do Disco Intervertebral , Núcleo Pulposo , Ratos , Animais , Proteínas Proto-Oncogênicas c-akt/fisiologia , Fosfatidilinositol 3-Quinase/metabolismo , Fosfatidilinositol 3-Quinase/uso terapêutico , Fosfatidilinositol 3-Quinases , Núcleo Pulposo/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Fator 2 Relacionado a NF-E2/uso terapêutico , Estresse Oxidativo , Degeneração do Disco Intervertebral/tratamento farmacológico , Degeneração do Disco Intervertebral/metabolismo , Apoptose
6.
Biomaterials ; 282: 121407, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35217343

RESUMO

Poor immunogenicity and compromised T cell infiltration impede the application of immune-checkpoint blockade (ICB) immunotherapy for osteosarcoma (OS). Although autophagy is involved in enhancing the immune response, the synergistic role of autophagy in ICB immunotherapy and the accurate control of autophagy levels in OS remain elusive and challenging. Here, we designed a pH-sensitive autophagy-controlling nanocarrier, CUR-BMS1166@ZIF-8@PEG-FA (CBZP), loading a natural derivative, curcumin (CUR), to boost the immunotherapeutic response of PD-1/PD-L1 blockade by activating immunogenic cell death (ICD) via autophagic cell death, and BMS1166 to inhibit the PD-1/PD-L1 interaction simultaneously, enhancing the tumor immunogenicity and sensitizing the antitumor T cell immunity. After entering tumor cells, the pH-sensitive nanoparticles induced autophagy and decreased the intracellular pH, which in turn further facilitated the release of CUR to enhance autophagic activity. Transferring CBZP to orthotopic OS tumor-bearing mice showed powerful antitumor effects and established long-term immunity against tumor recurrence, accompanied by enhanced dendritic cell maturation and tumor infiltration of CD8+ T lymphocytes. Collectively, CBZP exhibited synergistic effects in treating OS by combining ICD induction with checkpoint blockade, thereby shedding light on the use of autophagy control as a potential clinical therapy for OS.


Assuntos
Neoplasias Ósseas , Estruturas Metalorgânicas , Osteossarcoma , Animais , Autofagia , Antígeno B7-H1/metabolismo , Neoplasias Ósseas/terapia , Linhagem Celular Tumoral , Inibidores de Checkpoint Imunológico , Imunoterapia , Camundongos , Recidiva Local de Neoplasia , Osteossarcoma/terapia , Receptor de Morte Celular Programada 1 , Microambiente Tumoral
7.
Ann Transl Med ; 9(17): 1376, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34733928

RESUMO

BACKGROUND: Exosomes may contain excess cellular components released by cells in response to harmful external stimuli to maintain cellular homeostasis. Inflammatory cytokines, such as tumor necrosis factor-alpha (TNF-α), can induce cell apoptosis, alter cellular component expression levels, and stimulate exosome release. In this study, we examined whether exosomes released from nucleus pulposus cells (NPCs) under inflammatory conditions could induce normal NP cell apoptosis in rats and its underlining mechanism. METHODS: Exosomes were isolated from TNF-α-treated NPCs and used to treat normal NPCs. The effects were assessed by flow cytometry and western blot analysis. Anti-apoptotic insulin-like growth factor-1 (IGF-1) expression in NPCs was assessed by western blot analysis. Given the exosomal miRNAs might be the key factors of exosomes, bioinformatics approaches and quantitative real-time polymerase chain reaction (qRT-PCR) were used to identify IGF-1-regulating micro RNAs (miRNAs), including miR-16. Luciferase reporter assay assessed miR-16 regulation of IGF-1 and IGF-1 receptor (IGF-1R). NPCs were transfected with miR-16 mimic, and exosomes were applied to normal NPCs. NPCs were pretreated with 10 ng/mL TNF-α, transfected with miR-16 inhibitors, and the exosomes were isolated. Cell and exosome miR-16 levels were detected by qRT-PCR. Western blot analysis determined IGF-1, IGF-1R, and apoptotic marker levels in exosome-treated NPCs. RESULTS: Exosomes from TNF-α-treated NPCs induced apoptosis in normal NPCs and repressed IGF-1 expression. Exosomal miR-16 regulated IGF-1 and induced NPC apoptosis. The dual-luciferase reporter assay revealed that miR-16 binds the 3' untranslated regions (3'-UTRs) of IGF-1 and IGF-1R. Exosomal miR-16 repressed IGF-1 and the IGF-1R/phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) pathway which therefore induced NPC apoptosis. Rescue experiments using miR-16 inhibitors further validated these findings. CONCLUSIONS: The inflammatory factor TNF-α stimulated exosome release from NPCs, which induced the apoptosis of normal NPCs through the actions of exosomal miR-16. Exosomal miR-16 directly repressed the anti-apoptotic IGF-1/IGF-1R pathway, increasing the apoptosis of NPCs.

8.
Orthop Surg ; 11(1): 60-65, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30767427

RESUMO

OBJECTIVE: A retrospective study was designed to evaluate the effectiveness of CT-guided core needle biopsy in diagnosing spinal lesions through comparison with C-arm guidance. METHODS: From April 2013 to July 2017, a total of 188 patients, who suffered from spinal lesions or had malignant tumor history with a new spinal fracture, were included in this study. There were 96 men and 92 women, with an average of 57.1 years. A total of 238 core needle biopsies were performed. A total of 140 core needle biopsies were carried out under C-arm guidance in 102 patients (group 1); 98 core needle biopsies were carried out under CT guidance in 86 patients (group 2); 108 core needle biopsies were performed in thoracic vertebrae, 116 were in lumbar vertebrae, and 14 were in sacral vertebrae. Seventy-eight patients accepted surgical treatment after biopsies. For these patients, the histological pathologies of the biopsy and surgery were compared to evaluate the accuracy of the biopsy. For the other 110 patients who did not receive surgical treatment, the treatment response and the clinical course were used to evaluate the accuracy of the biopsy. The success rate, the diagnostic accuracy rate, the true positive/negative rate, and complications of the two groups were calculated and compared. RESULTS: There were no significant differences in sex, age, and lesion sites between the C-arm guidance group (group 1) and the CT guidance group (group 2). There were no complications in the two groups. Pathological diagnoses were established in 232 of 238 biopsies. They revealed that 52 were primary malignant tumors, 12 were benign tumors, 70 were metastatic tumors, 4 were tuberculosis, and 94 were classified as "other." The success rate of group 2 was higher than that of group 1, but it was not statistically significant (95.7% vs 100%; P = 0.098). According to the final diagnosis, the diagnostic accuracy rates were calculated and compared. There was no significant difference between the two groups (95.5% vs 96.9%; P = 0.835). The kappa coefficient was used to analyze the concordance between the histological pathologies of the biopsy and the final diagnosis in the two groups. The kappa values of the two group were 0.909 and 0.939, respectively. The results showed good consistency in both groups, but seemed better for group 2. CONCLUSION: CT-guided core needle biopsy is a relatively safe and effective procedure for diagnosing spinal lesions with a high diagnostic accuracy rate and few complications.


Assuntos
Biópsia com Agulha de Grande Calibre/métodos , Doenças da Coluna Vertebral/diagnóstico por imagem , Doenças da Coluna Vertebral/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia com Agulha de Grande Calibre/efeitos adversos , Diagnóstico Diferencial , Erros de Diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Radiografia Intervencionista/métodos , Estudos Retrospectivos , Neoplasias da Coluna Vertebral/diagnóstico por imagem , Neoplasias da Coluna Vertebral/patologia , Neoplasias da Coluna Vertebral/secundário , Tomografia Computadorizada por Raios X/métodos , Adulto Jovem
9.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 26(1): 208-212, 2018 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-29397845

RESUMO

OBJECTIVE: To explore the relationship between expression of CD96 and CD123 and prognosis of patients with myelodysplastic syndrome(MDS). METHODS: Eight-nine MDS patients(MDS group) and 20 persons without hematologic disease as controls(Control group) were enrolled. The patients were grouped by the risk. All participants received bone marrow biopsy. Mononuclear cells were extracted, CD34+CD38-CD123+ and CD34+CD38-CD96+ cells were counted by using flow cytometry. Expressions of 2 type cells in control group, MDS group and its subgroups were analyzed. RESULTS: The proportion of CD34+ cells and CD34+CD38- cells in mononuclear cells of patients in MDS group was higher than in control group (P<0.05). The proportions of CD34+CD38-CD123+ cells and CD34+CD38-CD96+ cells in CD34+CD38- cells were significantly higher than that in control group(P<0.05) and the proportion increased with the risk. In the low-and middle-risk group, the rates of complete remission(CR) and partial remission(PR) of patients with CD123- and CD96- were higher than those in patients with CD123+ and CD96+; in the middle-2 and high risk patients, the PR of patients with CD123- was higher than that in patients with CD123+(P<0.05). The CR rate of patients with CD96- was higher than that of patients with CD96+(P<0.05). CONCLUSION: The differentiation of CD34+ cells in bone marrow of MDS patients is abnormal, and the high expression of CD123 and CD96 cells existes. These findings may partially explain the cause of hematopoietic stem cell malignant clone in MDS patients.


Assuntos
Síndromes Mielodisplásicas , Antígenos CD , Antígenos CD34 , Células da Medula Óssea , Citometria de Fluxo , Células-Tronco Hematopoéticas , Humanos , Subunidade alfa de Receptor de Interleucina-3 , Prognóstico
10.
Int J Nanomedicine ; 12: 7197-7205, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29042769

RESUMO

STUDY DESIGN: This is an experimental animal study. OBJECTIVE: The objective of this study was to compare an anterior cervical discectomy and interbody fusion of a novel polylactide/nano-sized ß-tricalcium phosphate (PLA/nß-TCP) bioabsorbable self-retaining cervical fusion cage (BCFC) with an autologous bone graft and polyetheretherketone (PEEK) cages. BACKGROUND: Although PLA cervical cages have potential advantages compared with traditional materials, they are not currently routinely used in spine surgery because of undesirable effects such as the lack of osteoconductivity and osteolysis around the implant. This study involved the manufacturing of a bioabsorbable cage from PLA/nß-TCP that was then used as a device for anterior cervical discectomy and fusion (ACDF) on a goat cervical spine fusion model. MATERIALS AND METHODS: Eighteen goats underwent C3/C4 discectomy and were randomly divided into three groups based on the following methods: Group A (n=6), an autologous bone graft; Group B (n=6), PEEK cage filled with an autologous graft; and Group C (n=6), BCFC filled with an autologous iliac bone. Radiography was performed preoperatively and postoperatively and at 1, 4, 8, and 12 weeks after the operation. Disc space height (DSH) was measured at the same time. After 12 weeks, the fused segments were harvested and evaluated with functional radiographic views, biomechanical testing, and histological analyses. RESULTS: Over a 12-week period, the BCFC and PEEK cage groups exhibited significantly higher DSH values than the bone graft group. Additionally, the BCFC group yielded a significantly lower range of motion in axial rotation than both the autologous bone graft and PEEK cage groups. A histologic evaluation revealed an increased intervertebral bone volume/total volume ratio and better interbody fusion in the BCFC group than in the other groups. CONCLUSION: The BCFC device exhibited better results than the autologous bone graft and PEEK cages in single-level ACDF models in vivo. This device may be a potential alternative to the current PEEK cages.


Assuntos
Implantes Absorvíveis , Fosfatos de Cálcio/química , Vértebras Cervicais/cirurgia , Nanopartículas/química , Tamanho da Partícula , Poliésteres/química , Fusão Vertebral/instrumentação , Animais , Fenômenos Biomecânicos , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/fisiopatologia , Feminino , Reação a Corpo Estranho/patologia , Cabras , Disco Intervertebral/fisiopatologia , Disco Intervertebral/cirurgia , Modelos Animais , Amplitude de Movimento Articular
11.
Sci Rep ; 6: 38979, 2016 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-27941926

RESUMO

Osteoarthritis is a disease with inflammatory and catabolic imbalance in cartilage. Dihydroartemisinin (DHA), a natural and safe anti-malarial agent, has been reported to inhibit inflammation, but its effects on chondrocytes have yet to be elucidated. We investigated the effects of DHA on catabolism in chondrocytes. Viability of SD rats chondrocytes was analyzed. Autophagy levels were determined via expression of autophagic markers LC3 and ATG5, GFP-LC3 analysis, acridine orange staining, and electron microscopy. ATG5 siRNA induced autophagic inhibition. Catabolic gene and chemokine expression was evaluated using qPCR. The NF-κB inhibitor SM7368 and p65 over-expression were used to analyze the role of NF-κB pathway in autophagic activation. A concentration of 1 µM DHA without cytotoxicity increased LC3-II and ATG5 levels as well as autophagosomal numbers in chondrocytes. DHA inhibited TNF-α-induced expression of MMP-3 and -9, ADAMTS5, CCL-2 and -5, and CXCL1, which was reversed by autophagic inhibition. TNF-α-stimulated nuclear translocation and degradation of the p65 and IκBα proteins, respectively, were attenuated in DHA-treated chondrocytes. NF-κB inhibition activated autophagy in TNF-α-treated chondrocytes, but p65 over-expression reduced the autophagic response to DHA. These results indicate that DHA might suppress the levels of catabolic and inflammatory factors in chondrocytes by promoting autophagy via NF-κB pathway inhibition.


Assuntos
Artemisininas/administração & dosagem , Autofagia/efeitos dos fármacos , Condrócitos/efeitos dos fármacos , Condrócitos/metabolismo , NF-kappa B/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Inflamação/genética , Mediadores da Inflamação/metabolismo , Masculino , Metabolismo/efeitos dos fármacos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/administração & dosagem
12.
Orthop Surg ; 8(2): 97-104, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27384717

RESUMO

Spinal tumors result in high morbidity and a high rate of lower limb paralysis. Both surgical therapy and radiation therapy (RT) are used to treat spinal tumors; however, how best to combine these two therapies to maximize the benefits and minimize the risks is still being debated. It is also difficult to decide the optimal timing, course and dose of RT, especially in pregnant women and children. The aim of this review is to assist surgeons who are dealing with spinal tumors by providing comprehensive information about advanced techniques for administering RT with greater precision and safety, and about the impact of various ways of combining surgery and RT on therapeutic outcomes. We here review published reports about treating spinal tumors with a combination of these two forms of therapy and attempt to draw appropriate conclusions concerning selection of optimal treatment protocols. Our conclusion is that postoperative radiotherapy, especially with high-precision, low-dose and multiple fractions, and brachytherapy are promising therapies to combined with surgery.


Assuntos
Neoplasias da Coluna Vertebral/radioterapia , Neoplasias da Coluna Vertebral/cirurgia , Terapia Combinada , Humanos
14.
Int J Mol Sci ; 15(12): 22365-73, 2014 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-25479080

RESUMO

Extracellular acidification occurs under physiologic and pathologic conditions, such as exercise, ischemia, and inflammation. It has been shown that acidosis has various adverse effects on bone. In recent years there has been increasing evidence which indicates that ovarian cancer G protein-coupled receptor 1 (OGR1) is a pH-sensing receptor and mediates a variety of extracellular acidification-induced actions on bone cells and other cell types. Recent studies have shown that OGR1 is involved in the regulation of osteoclast differentiation, survival, and function, as well as osteoblast differentiation and bone formation. Moreover, OGR1 also regulates acid-induced apoptosis of endplate chondrocytes in intervertebral discs. These observations demonstrate the importance of OGR1 in skeletal development and metabolism. Here, we provide an overview of OGR1 regulation ofosteoclasts, osteoblasts, and chondrocytes, and the molecular actions of OGR1 induced by extracellular acidification in the maintenance of bone health.


Assuntos
Ácidos/metabolismo , Osso e Ossos/metabolismo , Espaço Extracelular/metabolismo , Neoplasias Ovarianas/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Animais , Feminino , Humanos , Prótons
15.
Orthopedics ; 35(12): e1822-5, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23218645

RESUMO

Lumbar interspinous devices are intended to unload the facet joints, restore foraminal height, lower intradisk pressure, and provide motion-preserving stabilization. They are an alternative treatment for patients with spinal degeneration and have increased in popularity in recent years. To the authors' knowledge, heterotopic ossification has not been previously reported around an interspinous device, and this is the first reported case of interspinous fusion after interspinous device placement.A 66-year-old man presented with a 3-year history of low back pain and a 4-month history of radiating pain down his left leg. A diagnosis was made of lumbar spinal stenosis and left disk herniation at L4-L5 after physical and imaging examinations. A dynamic interspinous device was implanted after the decompressive surgery. The patient's symptoms were relieved postoperatively. Thirty-two months later, he returned with back pain after being in a traffic accident. Lumbar radiographs showed a massive bony formation around the implant. Radiographs and a computed tomography scan 4.5 years later revealed that the implanted device segments were fused. No implant motion was seen on dynamic radiographs. Because the patient was symptom free, no interventions were performed.Heterotopic bone formation around a dynamic interspinous device may hamper motion preservation, and heterotopic ossification is a potential mid- and long-term complication.


Assuntos
Laminectomia/instrumentação , Vértebras Lombares/patologia , Ossificação Heterotópica/etiologia , Doenças da Coluna Vertebral/etiologia , Idoso , Descompressão Cirúrgica/instrumentação , Humanos , Deslocamento do Disco Intervertebral/cirurgia , Laminectomia/métodos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Masculino , Ossificação Heterotópica/diagnóstico por imagem , Próteses e Implantes , Doenças da Coluna Vertebral/diagnóstico por imagem , Tomografia Computadorizada por Raios X
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