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Acute myeloid leukaemia (AML) is a fatal haematopoietic malignancy and is treated with the conventional combination of cytarabine (Ara-C) and daunorubicin (Dau). The survival rate of AML patients is lower due to the cardiotoxicity of daunorubicin. Clinically, homoharringtonine (HHT) plus Ara-C has been reported to be equally effective as Dau plus Ara-C in some types of AML patients with less toxic effects. We utilized the clinical use of homoharringtonine in combination with Ara-C to test its combination mechanism. We found that the insensitivity of AML cells to cytarabine-induced apoptosis is associated with increased Mcl-1 stability and p38 inactivation. HHT downregulates Mcl-1, phosphorylates H2AX and induces apoptosis by activating p38 MAPK. Inactivation of p38 through inhibitors and siRNA blocks apoptosis, H2AX phosphorylation and Mcl-1 reduction. HHT enhances Ara-C activation of the p38 MAPK signalling pathway, overcoming Ara-C tolerance to cell apoptosis by regulating the p38/H2AX/Mcl-1 axis. The optimal ratio of HHT to Ara-C for synergistic lethality in AML cells is 1:4 (M/M). HHT synergistically induces apoptosis in combination with Ara-C in vitro and prolongs the survival of xenografts. We provide a new mechanism for AML treatment by regulating the p38 MAPK/H2AX/Mcl-1 axis to improve cytarabine therapy.
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Apoptose , Citarabina , Histonas , Mepesuccinato de Omacetaxina , Leucemia Mieloide Aguda , Proteína de Sequência 1 de Leucemia de Células Mieloides , Ensaios Antitumorais Modelo de Xenoenxerto , Proteínas Quinases p38 Ativadas por Mitógeno , Humanos , Mepesuccinato de Omacetaxina/farmacologia , Citarabina/farmacologia , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Leucemia Mieloide Aguda/genética , Apoptose/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Camundongos , Histonas/metabolismo , Linhagem Celular Tumoral , Sinergismo Farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Fosforilação/efeitos dos fármacos , FemininoRESUMO
Spinal cord injuries (SCI) are complex and cause complex neurological disorders with serious implications for the health of society. Excessive neuroinflammation is one of the pathogenesis of trauma-related central nervous system (CNS) dysfunction. The initiation of inflammatory response mainly stems from neuronal necrosis in the central nervous system. The therapeutic effects and underlying mechanisms of zinc targeting neurons were investigated in vivo and in vitro using protein chips, western blotting, reactive oxygen species (ROS) activity assays, ELISA, RT-qPCR, and immunostaining. In this study, we found that zinc promotes functional recovery. Specifically, we found that zinc increased neuronal survival and suppressed lesion size and focal apoptosis levels in vivo. Zinc administration confers neuroprotection by inhibiting NLRP3 inflammasome-associated cytokine levels probed with a protein chip. Furthermore, we found that zinc promoted SIRT3-mediated induction of autophagy, which abrogated inflammatory responses and mitochondrial ROS production in the injured spinal cord and cultured neurons. These findings suggest that zinc improves neuroinflammation and improves dyskinesia after SCI. In conclusion, zinc may be a potential therapeutic immunomodulatory challenge for the treatment of trauma-related CNS dysfunction.
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Sirtuína 3 , Traumatismos da Medula Espinal , Humanos , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Sirtuína 3/metabolismo , Zinco/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Doenças Neuroinflamatórias , Traumatismos da Medula Espinal/metabolismo , Medula Espinal/metabolismo , AutofagiaRESUMO
Parthanatos is a form of regulated cell death (RCD) that is closely linked to DNA damage, which is a common consequence of oxidative stress due to central nervous trauma, such as spinal cord injury (SCI). The mechanism by which apoptosis-inducing factor (AIF) mediates DNA strand breaks in parthanatos was not clear until the discovery of the nuclease function of MIF. A previous study suggested that observed results may not be reliable if the oxidative stress induced in cells observed under experimental pathological conditions does not accurately replicate the specific pathologies being studied. According to an earlier direct measurement of extracellular oxidative stress in a rat SCI model, post-SCI oxidative stress was approximately the same as exposure to 150 µM H2O2. However, this concentration has been reported as sublethal oxidative stress in other cell types related to senescence, apoptosis, and parthanatos. Using sublethal H2O2 concentrations to induce oxidative stress is equivocal. Also, different cell types have diverse tolerances and responses to oxidative stress, and, therefore, exposure to H2O2. To avoid these limitations, the present study explored the mechanism of neuronal death under this simulated post-SCI oxidative stress and determined the effects of MIF knockdown in parthanatos associated with SCI. Immunofluorescence and flow cytometry were used to reveal typical characteristics of parthanatos that were blocked by PARP-1 inhibitors but not caspase inhibitors. In addition to classic features like PARP-1 and caspase-3 cleavage that were absent, we determined that parthanatos instead of apoptosis played a major role in the cell death caused by oxidative stress following SCI. Flow cytometry analysis of cells transfected by adenovirus with MIF-shRNA then exposed to H2O2 showed a significant decrease in cell death for MIF knockdown cells, even after AIF nuclear translocation. The comet assay also displayed significantly fewer DNA strand breaks after MIF knockdown. This is the first study has verified that MIF knockdown enables to protect neurons from parthanatos under a simulated in vivo oxidative stress following SCI. It suggests that MIF knockdown is a promising therapy to rescue neurons suffering from oxidative stress-induced SCI pathology.
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Oxirredutases Intramoleculares/genética , Fatores Inibidores da Migração de Macrófagos/genética , Neurônios/metabolismo , Estresse Oxidativo , Parthanatos , Traumatismos da Medula Espinal/genética , Animais , Linhagem Celular , Movimento Celular , Técnicas de Silenciamento de Genes , Terapia Genética , Camundongos , Neurônios/citologia , Neurônios/patologia , Traumatismos da Medula Espinal/patologia , Traumatismos da Medula Espinal/terapiaRESUMO
Spinal cord injury (SCI) is one of the most serious nervous system disorders characterised by high morbidity and disability. Inflammatory and autophagy responses play an important role in the development of SCI. Metformin, a first-line drug for type-2 diabetes, features autophagy promotion as well as anti-inflammatory and anti-apoptotic properties in the nervous system. In this study, we investigated the neuroprotection effects of metformin preconditioning on rats after SCI. Results of Basso, Beattie and Bresnahan scores, HE staining and Nissl staining showed that the function and quantity of motor neurons were protected by metformin after SCI. Western blot revealed that the expression of Beclin-1 and LC3B-II was enhanced, and the phosphorylation levels of the mammalian target of rapamycin (mTOR) protein and p70S6K were reduced by metformin after SCI. Metformin significantly reduced the expression of NF-κB. Moreover, Western blot and immunofluorescence results indicated that caspase 3 activation was reduced, whereas bcl-2 level was significantly increased by metformin. Hence, metformin attenuated SCI by inhibiting apoptosis and inflammation and enhancing the autophagy via the mTOR/p70S6K signalling pathway.
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Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Inflamação/prevenção & controle , Metformina/farmacologia , Fármacos Neuroprotetores/farmacologia , Traumatismos da Medula Espinal/patologia , Animais , Feminino , Inflamação/complicações , NF-kappa B/metabolismo , Neurônios/patologia , Ratos , Ratos Sprague-Dawley , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Transdução de Sinais , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/metabolismo , Serina-Treonina Quinases TOR/metabolismoRESUMO
Traumatic spinal cord injury (SCI), often resulting from external physical trauma, initiates a series of complex pathophysiological cascades, with severe cases leading to paralysis and presenting significant clinical challenges. Traditional diagnostic and therapeutic approaches, particularly X-ray imaging, are prevalent in clinical practice, yet the limited efficacy and notable side effects of pharmacological treatments at the injury site continue to pose substantial hurdles. Addressing these challenges, recent advancements have been made in the development of multifunctional nanotechnology and synergistic therapies, enhancing both the efficacy and safety of radiographic techniques. In this context, we have developed an innovative nerve regeneration and neuroprotection nanoplatform utilizing an X-ray-triggered, on-demand RuFe metal-organic framework (P-RuFe) for SCI recovery. This platform is designed to simulate the enzymatic activities of catalase and superoxide dismutase, effectively reducing the production of reactive oxygen species, and to remove free radicals and reactive nitrogen species, thereby protecting cells from oxidative stress-induced damage. In vivo studies have shown that the combination of P-RuFe and X-ray treatment significantly reduces mortality in SCI mouse models and promotes spinal cord repair by inhibiting glial cell proliferation and neuroinflammation. P-RuFe demonstrates excellent potential as a safe, effective scavenger of reactive oxygen and nitrogen species, offering good stability, biocompatibility, and high catalytic activity, and thus holds promise for the treatment of inflammation-related diseases.
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The treatment of peripheral neuropathy resulting from diabetes primarily emphasizes neurotrophic medications. However, a growing body of clinical studies indicates that neuroinflammation plays a significant role in the pathogenesis of neuropathic pain. This has spurred active exploration of treatment strategies leveraging nanomedicine for diseases, aiming for superior therapeutic outcomes. In this context, we have developed biodegradable nanoparticles made of polylactic-co-glycolic acid, loaded with triptolide (pCel), designed to alleviate somatic cell neuropathic pain induced by diabetes. Treatment with pCel notably reduced levels of reactive oxygen species and apoptosis in vitro. Furthermore, the progression of streptozotocin-induced diabetes, characterized by elevated renal function indices (blood urea nitrogen, creatinine), liver function indices (bilirubin, alkaline phosphatase) and decreased levels of albumin and globulin, was mitigated following pCel administration. Importantly, oral treatment with pCel significantly inhibited mechanical allodynia and the activation of the sciatic glial cells in diabetic rats. These findings indicate that this synthetic, biodegradable nanomedicine exhibits excellent stability, biocompatibility and catalytic activity, making it a promising and innovative approach for the management of chronic pain conditions associated with diabetic neuropathy.
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Spinal cord injury is a serious traumatic nervous system disorder characterized by extensive neuronal apoptosis. Oxidative stress, a key factor in neuronal apoptosis, leads to the accumulation of reactive oxygen species, making mitochondrial quality control within cells crucial. Previous studies have demonstrated zinc's anti-inflammatory and anti-apoptotic properties in protecting mitochondria during spinal cord injury treatment, yet the precise mechanisms remain elusive. Single-cell sequencing analysis has identified Lgals3 and Bax as core genes in apoptosis. This study aimed to investigate whether zinc ions protect intracellular mitochondria by inhibiting the apoptotic proteins Lgals3 and Bax. We elucidated zinc ions' key role in mitigating mitochondrial quality control dysfunction triggered by oxidative stress and confirmed this was achieved by targeting the Lgals3-Bax pathway. Zinc's inhibitory effect on this pathway not only preserved mitochondrial integrity but also significantly reduced PANoptosis after spinal cord injury. Under oxidative stress, zinc ion regulation of mitochondrial quality control reveals an organelle-targeted therapeutic strategy, offering a novel approach for more precise treatment of spinal cord injury.
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Apoptose , Mitocôndrias , Neurônios , Estresse Oxidativo , Traumatismos da Medula Espinal , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/patologia , Traumatismos da Medula Espinal/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/patologia , Animais , Apoptose/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Neurônios/efeitos dos fármacos , Proteína X Associada a bcl-2/metabolismo , Proteína X Associada a bcl-2/genética , Zinco/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Modelos Animais de Doenças , Transdução de Sinais/efeitos dos fármacos , Camundongos , Humanos , RatosRESUMO
The recovery of infectious wound tissues presents a significant global health challenge due to the impediments posed by the harsh healing microenvironment, which includes ongoing bacterial invasion, high oxidative stress, inflammatory response, and impaired angiogenesis. To overcome the above issues, we propose a composite hydrogel based on the multiple-crosslinked mechanism involving the covalent network of CC bonds within catechol and maleic-modified HA (CMHA), the self-assembly network of glycyrrhizic acid (GA), and the metal-polyphenol coordination induced by ZHMCe for accelerating infectious wound healing. The resulting CMHA/GA/ZHMCe hydrogels demonstrate enhanced mechanical, adhesive, antioxidative, and antibacterial properties. Importantly, the hydrogel system possesses wound environment-responsive properties that allow it to adapt to the specific therapeutic requirements of different stages by regulating various enzyme activities in the healing of infected wounds. Furthermore, the biocompatible CMHA/GA/ZHMCe shows the ability to promote cell migration and angiogenesis in vitro while reprogramming macrophages toward an anti-inflammatory phenotype due to the effective release of active ingredients. In vivo experiments confirm that the CMHA/GA/ZHMCe hydrogel significantly enhances infectious wound healing by accelerating re-epithelialization, promoting collagen deposition, regulating inflammation, and contributing to vascularization. These findings underscore the therapeutic potential of our hydrogel dressings for the treatment of bacterially infected cutaneous wound healing.
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Ácido Hialurônico , Hidrogéis , Cicatrização , Hidrogéis/química , Hidrogéis/farmacologia , Cicatrização/efeitos dos fármacos , Animais , Camundongos , Ácido Hialurônico/química , Ácido Hialurônico/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Ácido Glicirrízico/farmacologia , Ácido Glicirrízico/química , Masculino , Células RAW 264.7 , Humanos , Infecção dos Ferimentos/tratamento farmacológico , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Antioxidantes/farmacologia , Antioxidantes/químicaRESUMO
Hydrogels possess inherent characteristics that render them promising for the prevention of peri-implantitis. Nonetheless, hydrogels with singular network structures are incapable of concurrently achieving the desired adhesion and mechanical properties. In this work, a carboxymethyl resistant starch/polyacrylic acid semi-interpenetrating (CMRS/PAA semi-IPN) hydrogel was successfully prepared in one step. Its morphology, structure, mechanical properties, and adhesion properties were systematically assessed, which revealed a homogeneously porous structure with a commendable mechanical strength of 67.317 kPa and an adhesion strength of 63 kPa. Ciprofloxacin (Cip) was loaded in the CMRS/PAA hydrogel via in situ compounding. The in vitro kinetic study of drug release shows that the slow drug release efficiency exceeds 90â¯% in the weakly acidic microenvironment at the infection site after 72â¯h, indicating enhanced antimicrobial properties. The Cip-loaded hydrogel also exhibits a remarkable bacterial inhibition rate exceeding 99â¯% against the pathogenic bacterium P. gingivalis and good cytocompatibility and hemocompatibility in vitro. In summary, the current work explored a novel solution and direction for the development of anti-infective medical materials applicable to dental implants.
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Chondroitin sulfate proteoglycans (CSPGs) and proteoglycan receptor protein tyrosine phosphatase σ (PTPσ) play a critical role in the pathology of spinal cord injury (SCI). CSPGs can be induced by autophagy inhibition in astrocyte. However, CSPG's impact on autophagy and its role in SCI is still unknown. We investigate intracellular sigma peptide (ISP) targeting PTPσ, its effects on autophagy, and synaptic reorganization in SCI. We found that ISP increased the level of autophagosome marker LC3B-II/I and decreased autophagosome degradation marker p62 in SCI, suggesting activated autophagy flux. ISP restored autophagosome-lysosome fusion-related protein syntaxin 17 (STX17) and lysosome-associated membrane protein 2 (LAMP2), indicating activated autophagosome-lysosome fusion. ISP increased pre-synaptic marker synaptophysin (SYN) and postsynaptic density protein-95 (PSD-95) expression and improved excitatory synapse marker vesicular glutamate transporter 1 (VGLUT1) and SYN in SCI, suggesting improved synaptic reorganization. ISP promoted axon marker neurofilament and growth-related GAP-43 expression in SCI. ISP rescued a preserved number of motor neurons and improved neurobehavioral recovery after SCI. Our study extended the CSPG-PTPσ inhibition role in activating autophagy flux, axon and synaptic reorganization, and functional recovery in SCI.
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Recently, injectable dual-crosslinked (DC) hydrogel scaffolds have attracted many attentions as a class of excellent bone regeneration biomaterials with in-situ tunable functions. However, the design of injectable DC hydrogels with cell behavior-compatible network structure and mechanical property remains a bottleneck. Herein, based on the in-situ gelling method, we constructed an injectable CMCS/PEG+SA/CaCl2 (CPSC) chemical/physical DC hydrogel scaffold with tunable softness/hardness mechanical properties and good biocompatibility. The formation mechanism and properties of the CPSC hydrogel scaffold were investigated by FTIR, XRD, rheometry, and mechanical testing. It is found that proper softness/hardness mechanical properties can be obtained by adjusting the secondary network structure of the hydrogel. The CPSC hydrogel scaffold prepared under optimal conditions can effectively promote cell infiltration, nutrient transport, and the osteogenic differentiation of rat bone mesenchymal stem cells (rBMSCs). The in vivo experiments show that the rBMSCs-loaded injectable CPSC hydrogels with appropriate mechanical properties can effectively promote bone reconstruction. This study has provided important guidance for the construction of injectable DC hydrogels with adjustable softness/hardness to promote osteogenesis for bone defect repair.
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Quitosana , Ratos , Animais , Quitosana/química , Hidrogéis/química , Osteogênese , Dureza , Alginatos/química , Regeneração Óssea , Engenharia Tecidual/métodos , Alicerces Teciduais/químicaRESUMO
The hyperinflammation microenvironment after spinal cord injury (SCI) remains a great challenge for neural regeneration. Methylprednisolone has been used to reduce the inflammatory response after SCI, but it is controversial due to side effects associated with off-specific targeting effects. In this study, we synthesized in situ 5-ASA grafted chitosan electrospun fibers (ASA-EF) with excellent injectable and self-healing properties to reprogram nerve cells via displaying biological distribution, gene expression, and functional changes. With the support of ASA-EF, the downregulation of inflammatory cytokines expression and the upregulation of anti-inflammatory and regenerative gene expression were found in vitro studies. Moreover, ASA-EF administration polarized macrophages toward proregenerative phenotypes in the injured lesion, and significantly reduced cavity area. In addition, ASA-EF administration increased myelination and regenerating axons and improved motor function (score of 5 versus 2 for SCI group). These results illustrate that the neuroprotective effect of this artificial nanoplatform will facilitate the clinical treatment of traumatic-related diseases via forming a recycled microenvironment that supports regeneration and functional recovery. These particles may be applied to trauma and potential other inflammatory diseases.
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Microglia, immune cells in the central nervous system (CNS), mediate inflammatory responses and provide support to the microenvironment. Neurotoxic microglia predominantly locate in the injured spinal cord that delay spinal cord injury (SCI) repair. We previously found that melatonin could suppress SCI-induced neuronal inflammatory activation. However, the effect of melatonin in microglia responses remains unclear. In this study, isolated primary microglia and neurons were stimulated with lipopolysaccharide (LPS) and interferon-γ (IFN-γ) or melatonin-containing medium. We found that melatonin supported the beneficial polarization from pro-inflammatory to anti-inflammation, downrehulated ROS activity, and recovered mitochondrial metabolism in vitro and in vivo. Furthermore, melatonin downregulated pro-inflammatory-related mRNA levels. These results suggested that melatonin may be therapeutic potential for neuroinflammation-related neurological disorders, such as SCI.
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Melatonina , Traumatismos da Medula Espinal , Humanos , Microglia , Melatonina/farmacologia , Melatonina/uso terapêutico , Melatonina/metabolismo , Traumatismos da Medula Espinal/tratamento farmacológico , Traumatismos da Medula Espinal/metabolismo , Medula Espinal , Fenótipo , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Anti-Inflamatórios/metabolismoRESUMO
Fluorine pollution has become a global public health problem due to its adverse health effects. Adsorption is the primary method for removing fluoride from drinking water. However, the adsorption method has disadvantages such as difficulty in recovering the adsorbent, and the need to add additional chemicals for regeneration, thereby causing secondary pollution, which limits further industrial applications. Capacitive deionization (CDI), as an emerging water treatment technology, has attracted widespread attention due to its advantages of simple operation, low energy consumption and less environmental impact. In this study, a polypyrrole (PPy) film was prepared on a graphite substrate by electrodeposition, and then metal-organic framework Ce/Zn-BDC-NH2 (CZBN) was deposited on the PPy film by electrophoretic deposition to obtain CZBN/PPy electrode was obtained. The CZBN/PPy anode was then coupled with the MnO2 cathode for capacitive removal of fluoride in a CDI cell. Both CZBN/PPy and MnO2 electrodes exhibit pseudocapacitive behavior, which can selectively and reversibly intercalate F- (CZBN/PPy) and Na+ (MnO2) ions. As expected, the CZBN/PPy-MnO2 system exhibits excellent fluorine removal performance. In 1.2 V, 100 mg/L F- solution, the F- removal capacity can reach 55.12 mg/g. It has high F- selectivity in the presence of some common anions, and can maintain high F- removal ability even after five adsorption regeneration processes. The mechanism of F- removal was studied by Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). F- was mainly removed by electrostatic interaction and ion exchange with hydroxyl. The excellent defluorination performance of the CZBN/PPy-MnO2 system makes it have good practical application prospects.
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Polímeros , Purificação da Água , Polímeros/química , Pirróis/química , Fluoretos , Flúor , Galvanoplastia , Compostos de Manganês , Óxidos , Eletrodos , Purificação da Água/métodosRESUMO
Liver metastasis is the leading cause of death in colorectal carcinoma (CRC). However, little is known about the mechanisms of transferring effector messages between the primary tumor and the site of metastasis. Exosomes provide a novel transfer message method, and exosomal circular RNAs (circRNAs) play critical regulatory roles in cancer biology. In this study, the results showed that the expression of circPABPC1 was aberrantly upregulated in CRC tissues and exosomes. Exosomal circPABPC1 was considered an oncogene by functional experimental analysis in vitro and in vivo. Mechanistically, circPABPC1 recruited KDM4C to the HMGA2 promoter, reduced its H3K9me3 modification and initiated the transcription process in the nucleus. Moreover, cytoplasmic circPABPC1 promoted CRC progression by protecting ADAM19 and BMP4 from miR-874-/miR-1292-mediated degradation. Our findings indicated that exosomal circPABPC1 is an essential regulator in CRC liver metastasis progression by promoting HMGA2 and BMP4/ADAM19 expression. CircPABPC1 is expected to be a novel biomarker and antimetastatic therapeutic target in CRC.
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OBJECTIVES: Osteoblasts are derived from Bone Marrow-derived Mesenchymal Stem Cells (BM-MSCs), which play an indispensable role in bone formation. In this study, the authors aim to investigate the role of IRF4 in the osteogenic differentiation of BM-MSCs and its potential molecular mechanism. METHODS: The authors used lentivirus infection to overexpress IRF4 in BM-MSCs. The expression of IRF4 and osteogenesis-related genes were detected by qRT-PCR and western blot analysis. The osteogenic differentiation of BM-MSCs was evaluated by Alkaline Phosphatase (ALP) activity, Alizarin red staining, and Alkaline Phosphatase (ALP) staining. Chromatin Immunoprecipitation (ChIP), Dual-Luciferase reporter assay and RNA Immunoprecipitation Assay were applied to confirm the regulatory mechanism between IRF4, miR-636 and DOCK9. RESULTS: The authors found IRF4 was down-regulated during the osteogenic differentiation of BM-MSCs, and IRF4 overexpression could decrease the osteogenic differentiation of BM-MSCs by specifically promoting the reduction of Alkaline Phosphatase (ALP) activity and down-regulating osteogenic indicators, including OCN, OPN, Runx2 and CollA1. Mechanistically, IRF4 activated microRNA-636 (miR-636) expression via binding to its promoter region, and Dedicator of Cytokinesis 9 (DOCK9) was identified as the target of miR-636 in BM-MSCs. Moreover, the damage in the capacity of osteogenic differentiation of BM-MSCs induced by IRF4 overexpression could be rescued by miR-636 inhibition. CONCLUSIONS: In summary, this paper proposed that IRF4/miR-636/DOCK9 may be considered as targets for the treatment of osteoporosis (OP).
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Fatores de Troca do Nucleotídeo Guanina , Fatores Reguladores de Interferon , Células-Tronco Mesenquimais , MicroRNAs , Fosfatase Alcalina , Diferenciação Celular/genética , Células Cultivadas , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Fatores Reguladores de Interferon/metabolismo , MicroRNAs/genética , Osteogênese/genéticaRESUMO
Spinal cord injury (SCI) can cause severe trauma to the central nervous system. Resveratrol has been widely studied for several of its medicinal properties, including anti-inflammatory, anti-aging and anti-oxidative effects. The regulation of SIRT-1 is thought to be related to the effects of resveratrol. As a downstream component of SIRT-1, NF-κB is one of the important signaling pathways that regulate the inflammatory response. Herein, we explored how treatment with resveratrol promoted recovery of motor function after SCI by activating the SIRT-1/NF-κB signaling pathway and inhibiting inflammation in rat models. Recovery of hind limb function was observed using the Basso, Beattie, and Bresnahan locomotor rating scale at different time points after SCI. Western blot analysis, immunofluorescence, Nissl staining and HE staining were utilized to observe the morphological characteristics of spinal cord tissue, as well as the expression of SIRT-1, NF-κB, TNF-α, IL-1ß, IL-6 and brain-derived neurotrophic factor. Resveratrol treatment promoted motor function recovery, increased the expression of brain-derived neurotrophic factor, and reduced loss of motor neurons and lesion size among rats after SCI. Meanwhile, inflammatory response was inhibited as the SIRT-1/NF-κB signaling pathway was modulated. These results suggest that resveratrol can help achieve neuroprotective effect by inhibiting inflammation, regulated by the SIRT-1/NF-κB signaling pathway.
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Inflamação/patologia , NF-kappa B/efeitos dos fármacos , Resveratrol/farmacologia , Sirtuína 1/efeitos dos fármacos , Traumatismos da Medula Espinal/patologia , Animais , Anti-Inflamatórios/farmacologia , Feminino , Fármacos Neuroprotetores/farmacologia , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Sirtuína 1/metabolismoRESUMO
OBJECTIVES: Resveratrol has been recognized as a potential therapeutic drug in spinal cord injury (SCI). Sirtuin 1 (SIRT1) is vital in the regulation of apoptosis and cell stress response. In this research, our purpose was to explore the mechanisms of resveratrol on neuroprotection and to explore the role of SIRT1. MATERIALS AND METHODS: We used lipopolysaccharide (LPS) in the VSC4.1 spinal cord neuron cell line to mimic the micro-environment of the injured spinal cord. The apoptosis of VSC4.1 motoneurons was assessed by TUNEL staining, Western blot, and RT-PCR. Immunofluorescence staining was used to observe the expression site of SIRT1, LC3-B, and Beclin-1, and their protein levels were measured by Western blot and RT-PCR. RESULTS: Our results showed that resveratrol inhibits LPS-induced apoptosis in VSC4.1 motoneurons. Levels of LC3-B, beclin-1, and SIRT1 indicated a significant increase after resveratrol treatment. But, if autophagy was inhibited, apoptosis in VSC4.1 motoneurons significantly increased. When the cells were treated with EX527, a SIRT1 inhibitor, the protein contents of LC3-B and Beclin-1 were suppressed. CONCLUSION: Resveratrol inhibits apoptosis through promoting autophagy in VSC4.1 motoneurons. SIRT1 was involved in autophagy activated by resveratrol in VSC4.1 motoneurons.
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Macrophages and microglia (M/Ms) in the injured spinal cord maintain a predominantly neurotoxic M1 phenotype that is disadvantageous to repair in the development of spinal cord injury (SCI). It has been reported that tumor necrosis factor (TNF) that polarize M/Ms toward M1 state in various disorders. In this study, we found that ablation of TNF endorsed the beneficial conversion from M1 to M2 phenotype and improved the mitochondrial metabolism in vivo and in vitro. In addition, PGC-1α that accumulates in TNF null mice, a major participant of mitochondrial metabolism, downregulated ROS activity and the expressions of M1-specific mRNA. Moreover, the absence of TNF upgraded the morphology and quantity of damaged mitochondria and rapidly switched to M2 phenotype as compare to administration of N-Acetyl-l-cysteine (NAC). Furthermore, systemic application of TPEN showed that increased ratio of M1 M/Ms. These combined results supporting predominant and prolonged TNF expression that is destructive to recovery after SCI. These results indicated that TNF would have great potential immunomodulatory for the treatment of SCI.
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Microglia , Fator de Necrose Tumoral alfa , Animais , Humanos , Macrófagos/metabolismo , Camundongos , Microglia/metabolismo , Mitocôndrias , Medula Espinal , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Spinal cord injury (SCI) is one of the most destructive diseases. The neuroinflammation microenvironment needs comprehensive mitigation of damages. Thus, regulation of local, microenvironment drugs could be a potential effective treatment. However, clinical studies on SCI with common treatment have reported it to cause systemic toxicity and side effects. Zinc oxide nanoparticles (ZnONPs) have been widely reported to have satisfying anti-inflammation function. Furthermore, green synthesis procedures can improve the capability and possible utilization of ZnONPs. However, the efficient administration and underlying mechanism of ZnONPs in SCI treatment remain unclear. Herein, an innovative approach was built by utilizing ZnONPs loaded in a skeletal muscle-derived adhesive hydrogel (ZnONPs-Gel). Different from the systemic application of ZnONPs, the local administration of ZnONPs-Gel offered the ZnONPs-loaded extracellular matrix with beneficial biocompatibility to the injured spinal cord, thereby promoting effective function recovery. Mechanistically, the ZnONPs-Gel treatment not only markedly reduced ROS production but also decreased apoptosis in the injured spinal cord. Therefore, the strategy based on local administration of the ZnONPs-Gel in the early stage of SCI may be an effective therapeutic treatment.