RESUMEN
One-carbon metabolism is essential for our human cells to carry out nucleotide synthesis, methylation, and reductive metabolism through one-carbon units, and these pathways ensure the high proliferation rate of cancer cells. Serine hydroxymethyltransferase 2 (SHMT2) is a key enzyme in one-carbon metabolism. This enzyme can convert serine into a one-carbon unit bound to tetrahydrofolate and glycine, ultimately supporting the synthesis of thymidine and purines and promoting the growth of cancer cells. Due to SHMT2's crucial role in the one-carbon cycle, it is ubiquitous in human cells and even in all organisms and highly conserved. Here, we summarize the impact of SHMT2 on the progression of various cancers to highlight its potential use in the development of cancer treatments.
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Glicina Hidroximetiltransferasa , Procesamiento Proteico-Postraduccional , Humanos , Proliferación Celular , Glicina Hidroximetiltransferasa/genética , Glicina Hidroximetiltransferasa/metabolismo , Serina/metabolismoRESUMEN
Spinal cord injury (SCI) is a complex pathological change that includes primary SCI and gradually evolves into secondary SCI. Accumulating evidence demonstrates that circular RNAs (circRNAs) are involved in the pathology of a variety of neurological diseases and injuries. However, the characteristics and function of circRNAs in SCI have yet to be elucidated. Although previous research demonstrated that circPrkcsh induces astrocytes to produce inflammatory factors and chemokines, the precise function and mechanism of circPrkcsh in microglia after SCI remains unknown. In this study, we constructed a mouse model of SCI by applying a SCI impactor. Quantitative Real-time PCR and Fluorescence in situ hybridization analysis revealed that circPrkcsh was upregulated in the microglia of SCI mice when compared to sham-operated mice. Gain- or loss-of-function experiments and in vivo assays further indicated that circPrkcsh promotes microglia M1 polarization both in vivo and in vitro. Furthermore, bioinformatics analysis, dual-luciferase assays, and RNA immunoprecipitation assays, confirmed that circPrkcsh serves as a competing endogenous RNA (ceRNA) to promote the expression of MEKK1 mRNA by sponging miR-488. Double knockout rescue experiments further showed that circPrkcsh regulates the MEKK1/JNK/p38 MAPK pathway via miR-488. Our research provides a better understanding of the mechanism of circPrkcsh in SCI and demonstrates that the circPrkcsh/miR-488/Mekk1 axis is a promising regulatory method for the treatment of SCI.
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Glucosidasas/genética , Péptidos y Proteínas de Señalización Intracelular/genética , Sistema de Señalización de MAP Quinasas , Macrófagos/inmunología , MicroARNs/genética , ARN Circular/genética , Traumatismos de la Médula Espinal/patología , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Animales , Apoptosis , Modelos Animales de Enfermedad , Regulación de la Expresión Génica , Macrófagos/metabolismo , Macrófagos/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Fenotipo , Transducción de Señal , Traumatismos de la Médula Espinal/etiología , Traumatismos de la Médula Espinal/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/genéticaRESUMEN
BACKGROUND: Cardiac fibrosis will increase wall stiffness and diastolic dysfunction, which will eventually lead to heart failure. Asenapine maleate (AM) is widely used in the treatment of schizophrenia. In the current study, we explored the potential mechanism underlying the role of AM in angiotensin II (Ang II)-induced cardiac fibrosis. METHODS: Cardiac fibroblasts (CFs) were stimulated using Ang II with or without AM. Cell proliferation was measured using the cell counting kit-8 assay and the Cell-Light EdU Apollo567 In Vitro Kit. The expression levels of proliferating cell nuclear antigen (PCNA) and α-smooth muscle actin (α-SMA) were detected using immunofluorescence or western blotting. At the protein level, the expression levels of the components of the transforming growth factor beta 1 (TGFß1)/mitogen-activated protein kinase (MAPK) signaling pathway were also detected. RESULTS: After Ang II stimulation, TGFß1, TGFß1 receptor, α-SMA, fibronectin (Fn), collagen type I (Col1), and collagen type III (Col3) mRNA levels increased; the TGFß1/MAPK signaling pathway was activated in CFs. After AM pretreatment, cell proliferation was inhibited, the numbers of PCNA -positive cells and the levels of cardiac fibrosis markers decreased. The activity of the TGFß1/MAPK signaling pathway was also inhibited. Therefore, AM can inhibit cardiac fibrosis by blocking the Ang II-induced activation through TGFß1/MAPK signaling pathway. CONCLUSIONS: This is the first report to demonstrate that AM can inhibit Ang II-induced cardiac fibrosis by down-regulating the TGFß1/MAPK signaling pathway. In this process, AM inhibited the proliferation and activation of CFs and reduced the levels of cardiac fibrosis markers. Thus, AM represents a potential treatment strategy for cardiac fibrosis.
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Angiotensina II/farmacología , Dibenzocicloheptenos/farmacología , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Animales , Diferenciación Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Fibroblastos/citología , Fibrosis/metabolismo , Fibrosis/prevención & control , Miocardio/citología , Miocardio/metabolismo , Ratas , Ratas Wistar , Esquizofrenia/tratamiento farmacológicoRESUMEN
OBJECTIVES: Osteoarthritis (OA) is the most common joint disease; however, the indeterminate nature of mechanisms by which OA develops has restrained advancement of therapeutic targets. TNF signalling has been implicated in the pathogenesis of OA. TNFR1 primarily mediates inflammation, whereas emerging evidences demonstrate that TNFR2 plays an anti-inflammatory and protective role in several diseases and conditions. This study aims to decipher TNFR2 signalling in chondrocytes and OA. METHODS: Biochemical copurification and proteomics screen were performed to isolate the intracellular cofactors of TNFR2 complex. Bulk and single cell RNA-seq were employed to determine 14-3-3 epsilon (14-3-3ε) expression in human normal and OA cartilage. Transcription factor activity screen was used to isolate the transcription factors downstream of TNFR2/14-3-3ε. Various cell-based assays and genetically modified mice with naturally occurring and surgically induced OA were performed to examine the importance of this pathway in chondrocytes and OA. RESULTS: Signalling molecule 14-3-3ε was identified as an intracellular component of TNFR2 complexes in chondrocytes in response to progranulin (PGRN), a growth factor known to protect against OA primarily through activating TNFR2. 14-3-3ε was downregulated in OA and its deficiency deteriorated OA. 14-3-3ε was required for PGRN regulation of chondrocyte metabolism. In addition, both global and chondrocyte-specific deletion of 14-3-3ε largely abolished PGRN's therapeutic effects against OA. Furthermore, PGRN/TNFR2/14-3-3ε signalled through activating extracellular signal-regulated kinase (ERK)-dependent Elk-1 while suppressing nuclear factor kappa B (NF-κB) in chondrocytes. CONCLUSIONS: This study identifies 14-3-3ε as an inducible component of TNFR2 receptor complex in response to PGRN in chondrocytes and presents a previously unrecognised TNFR2 pathway in the pathogenesis of OA.
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Proteínas 14-3-3/metabolismo , Cartílago Articular/metabolismo , Condrocitos/metabolismo , Osteoartritis/metabolismo , Receptores Tipo II del Factor de Necrosis Tumoral/metabolismo , Animales , Cartílago Articular/citología , Humanos , Ratones , Ratones Noqueados , FN-kappa B/metabolismo , Progranulinas/metabolismo , Transducción de Señal , Proteína Elk-1 con Dominio ets/metabolismoRESUMEN
Inflammatory Bowel Disease (IBD) is an autoimmune condition with complicated pathology and diverse clinical signs. TNFα is believed to play a crucial role in the pathogenesis of IBD. We recently identified fexofenadine, a well-known antagonist of histamine H1 receptor, as a novel inhibitor of TNFα signaling. Additionally, cytosolic phospholipase A2 (cPLA2) was isolated as a binding target of fexofenadine, and fexofenadine-mediated anti-TNF activity relied on cPLA2 in vitro. The objective of this study is to determine whether fexofenadine is therapeutic against chemically-induced murine IBD model and whether cPLA2 and/or histamine H1 receptor is important for fexofenadine's anti-inflammatory activity in vivo by leveraging various genetically modified mice and chemically induced murine IBD models. Both dextran sulfate sodium- and 2, 4, 6-trinitrobenzene sulfonic acid-induced murine IBD models revealed that orally delivered fexofenadine was therapeutic against IBD, evidenced by mitigated clinical symptoms, decreased secretions of the proinflammatory cytokine IL-6 and IL-1ß, lowered intestinal inflammation, and reduced p-p65 and p-IĸBα. Intriguingly, Fexofenadine-mediated protective effects against IBD were lost in cPLA2 deficient mice but not in histamine H1 receptor-deficient mice. Collectively, these findings demonstrate the therapeutic effects of over-the-counter drug Fexofenadine in treating DSS-induced IBD murine and provide first in vivo evidence showing that cPLA2 is required for fexofenadine's therapeutic effects in murine IBD model and probably other inflammatory and autoimmune diseases as well.
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Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Fosfolipasas A2 Citosólicas/fisiología , Terfenadina/análogos & derivados , Animales , Biomarcadores Farmacológicos , Modelos Animales de Enfermedad , Enfermedades Inflamatorias del Intestino/genética , Enfermedades Inflamatorias del Intestino/patología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Fosfolipasas A2 Citosólicas/genética , Terfenadina/uso terapéuticoRESUMEN
Ischemic spinal cord injury (ISCI) results in the motor sensory dysfunction of the limbs below the injury site. In response to the injury, astrocytes develop into neuroprotective astrocytes [(neurotrophic reactive astrocytes (A2s)] to mitigate the damage. MicroRNA (miR)-21 can promote the development of neuroinflammation in previous studies. Our aim was to investigate the effect of miR-21 on its polarization. We used the abdominal aortic occlusion model in vivo. Immunohistochemistry was used to detect the distribution of A2s in the spinal cord. We used an oxygen glucose deprivation method to model astrocytes ischemia in vitro and tested proliferation, migration, and excitability of A2s using an 5-ethynyl -2'-deoxyuridine kit, wound scratch assay, and calcium-ion probe. After adjustment, we detected the model and target genes of A2s using PCR, Western blot, immunofluorescence, and chromatin immunoprecipitation. We demonstrated in vivo that naive astrocytes were transformed into A2s by ischemia. And in vitro miR-21, which can regulate the signal transducer and activator of transcription-3 pathway, can transform neurotoxic reactive astrocyte into A2. Moreover, we also verified the mechanism of A2s promoting synaptic formation and nerve growth. miR-21 is a switch to regulate the polarization of reactive astrocyte, and it promoted synapsis formation and nerites growth after acute ISCI.-Su, Y., Chen, Z., Du, H., Liu, R., Wang, W., Li, H., Ning, B. Silencing miR-21 induces polarization of astrocytes to the A2 phenotype and improves the formation of synapses by targeting glypican 6 via the signal transducer and activator of transcription-3 pathway after acute ischemic spinal cord injury.
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Astrocitos/metabolismo , Glipicanos/metabolismo , MicroARNs/metabolismo , Factor de Transcripción STAT3/metabolismo , Traumatismos de la Médula Espinal/metabolismo , Sinapsis/metabolismo , Animales , Astrocitos/citología , Células Cultivadas , Femenino , Ratones , Ratones Endogámicos C57BL , MicroARNs/genética , Neurogénesis , Neuronas/citología , Neuronas/metabolismoRESUMEN
PURPOSE: Spinal cord injury (SCI) often results in significant and catastrophic dysfunction and disability and imposes a huge economic burden on society. This study aimed to determine whether progranulin (PGRN) plays a role in the progressive damage following SCI and evaluate the potential for development of a PGRN derivative as a new therapeutic target in SCI. METHODS: PGRN-deficient (Gr-/-) and wild-type (WT) littermate mice were subjected to SCI using a weight-drop technique. Local PGRN expression following injury was evaluated by Western blotting and immunofluorescence. Basso Mouse Scale (BMS), inclined grid walking test, and inclined plane test were conducted at indicated time points to assess neurological recovery. Inflammation and apoptosis were examined by histology (Hematoxylin and Eosin (H&E) staining and Nissl staining, TUNEL assays, and immunofluorescence), Western blotting (from whole tissue protein for iNOS/p-p65/Bax/Bcl-2), and ex vivo ELISA (for TNFα/IL-1ß/IL-6/IL-10). To identify the prophylactic and therapeutic potential of targeting PGRN, a PGRN derived small protein, Atsttrin, was conjugated to PLGA-PEG-PLGA thermosensitive hydrogel and injected into intrathecal space prior to SCI. BMS was recorded for neurological recovery and Western blotting was applied to detect the inflammatory and apoptotic proteins. RESULTS: After SCI, PGRN was highly expressed in activated macrophage/microglia and peaked at day 7 post-injury. Grn-/- mice showed a delayed neurological recovery after SCI at day 21, 28, 35, and 42 post-injury relative to WT controls. Histology, TUNEL assay, immunofluorescence, Western blotting, and ELISA all indicated that Grn-/- mice manifested uncontrolled and expanded inflammation and apoptosis. Administration of control-released Atsttrin could improve the neurological recovery and the pro-inflammatory/pro-apoptotic effect of PGRN deficiency. CONCLUSION: PGRN deficiency exacerbates SCI by promoting neuroinflammation and cellular apoptosis, which can be alleviated by Atsttrin. Collectively, our data provide novel evidence of using PGRN derivatives as a promising therapeutic approach to improve the functional recovery for patients with spinal cord injury.
Asunto(s)
Apoptosis/fisiología , Inflamación/metabolismo , Progranulinas/metabolismo , Traumatismos de la Médula Espinal/metabolismo , Animales , Citocinas/metabolismo , Femenino , Inflamación/genética , Ratones , Ratones Noqueados , Óxido Nítrico Sintasa de Tipo II/metabolismo , Progranulinas/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Recuperación de la Función/fisiología , Traumatismos de la Médula Espinal/genética , Regulación hacia Arriba , Proteína X Asociada a bcl-2/metabolismoRESUMEN
OBJECTIVE: Tumour necrosis factor alpha (TNF-α) signalling plays a central role in the pathogenesis of various autoimmune diseases, particularly inflammatory arthritis. This study aimed to repurpose clinically approved drugs as potential inhibitors of TNF-α signalling in treatment of inflammatory arthritis. METHODS: In vitro and in vivo screening of an Food and Drug Administration (FDA)-approved drug library; in vitro and in vivo assays for examining the blockade of TNF actions by fexofenadine: assays for defining the anti-inflammatory activity of fexofenadine using TNF-α transgenic (TNF-tg) mice and collagen-induced arthritis in DBA/1 mice. Identification and characterisation of the binding of fexofenadine to cytosolic phospholipase A2 (cPLA2) using drug affinity responsive target stability assay, proteomics, cellular thermal shift assay, information field dynamics and molecular dynamics; various assays for examining fexofenadine inhibition of cPLA2 as well as the dependence of fexofenadine's anti-TNF activity on cPLA2. RESULTS: Serial screenings of a library composed of FDA-approved drugs led to the identification of fexofenadine as an inhibitor of TNF-α signalling. Fexofenadine potently inhibited TNF/nuclear factor kappa-light-chain-enhancer of activated B cells (NF-ĸB) signalling in vitro and in vivo, and ameliorated disease symptoms in inflammatory arthritis models. cPLA2 was isolated as a novel target of fexofenadine. Fexofenadine blocked TNF-stimulated cPLA2 activity and arachidonic acid production through binding to catalytic domain 2 of cPLA2 and inhibition of its phosphorylation on Ser-505. Further, deletion of cPLA2 abolished fexofenadine's anti-TNF activity. CONCLUSION: Collectively, these findings not only provide new insights into the understanding of fexofenadine action and underlying mechanisms but also provide new therapeutic interventions for various TNF-α and cPLA2-associated pathologies and conditions, particularly inflammatory rheumatic diseases.
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Artritis Experimental/tratamiento farmacológico , Fosfolipasas A2 Citosólicas/efectos de los fármacos , Terfenadina/análogos & derivados , Inhibidores del Factor de Necrosis Tumoral/farmacología , Animales , Ratones , Ratones Endogámicos DBA , Ratones Transgénicos , Transducción de Señal/efectos de los fármacos , Terfenadina/farmacología , Factor de Necrosis Tumoral alfa/antagonistas & inhibidoresRESUMEN
Traumatic spinal cord injury (SCI) causes permanent disability to at least 180,000 people per year worldwide. Early regulation of spinal fibroblast proliferation may inhibit fibrotic scar formation, allowing the creation of a favorable environment for neuronal regeneration and thereby enhancing recovery from traumatic SCIs. In this study, we aimed to identify the role of microRNA-21a-5p (miR-21a-5p) in regulating spinal fibroblasts after mechanical trauma and to investigate the dysregulation of miR-21a-5p in the pathological process of spinal SCI. We investigated the differential expression of microRNAs in primary spinal fibroblasts after mechanical trauma and found that the expression of miR-21a-5p was higher in spinal fibroblasts after scratch damage (SD). In addition, mouse spinal fibroblasts were transfected with miR-21a-5p mimics/inhibitor, and the role of miR-21a-5p in spinal fibrogenic activation was analyzed. These experiments demonstrated that miR-21a-5p overexpression promoted fibrogenic activity in spinal fibroblasts after mechanical trauma, as well as enhancing proliferation and attenuating apoptosis in spinal fibroblasts. Finally, the potential role of miR-21a-5p in regulating the Smad signaling pathway was examined. MiR-21a-5p activated the Smad signaling pathway by enhancing Smad2/3 phosphorylation. These results suggest that miR-21a-5p promotes spinal fibrosis after mechanical trauma. Based on these findings, we propose a close relationship between miR-21a-5p and spinal fibrosis, providing a new potential therapeutic target for SCI.
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Fibroblastos/patología , Fibrosis/genética , MicroARNs/genética , Traumatismos de la Médula Espinal/genética , Animales , Apoptosis/genética , Proliferación Celular/genética , Células Cultivadas , Fibrosis/patología , Ratones , Fosforilación/genética , Transducción de Señal/genética , Traumatismos de la Médula Espinal/patologíaRESUMEN
To assess the therapeutic effects of microRNA-21 (miR-21) knockdown (KD) for acute thoracic spinal cord contusion using a mouse model. Forty C57/BL6 mice were randomly divided into four groups: mice in the sham-operated (Sham) group received surgical procedure without spinal cord contusion; the spinal cord injury (SCI) group mice underwent spinal cord contusion without treatment; mice in the miR-21 KD group underwent spinal cord contusion followed by a single dose subdural injection of miR-21 KD vectors (1 × 107 TU); and the negative control (NC) group mice were given subdural injection of comparable amount of NC vectors (1 × 107 TU) after spinal cord contusion. The Basso Mouse Scale (BMS) was employed to assess hindlimb motor functions. Hematoxylin-eosin and Luxol fast blue staining were performed to evaluate pathologic changes in spinal cord tissues. Peripheral blood serum levels of tumor necrosis factor α (TNFα), transforming growth factor ß (TGF-ß) and interleukin-1ß (IL-1ß) were determined by the enzyme-linked immunosorbent assay, and mRNA expression of Brain derived neurotrophic factor (BDNF) was examined by reverse transcription-polymerase chain reaction (RT-PCR). Western blotting was performed to analyze the AKT signaling pathway. KD of miRNA-21 effectively improved the BMS scores at day 14 post-surgery compared with the SCI group (p < 0.01). The spinal cord tissue in the miR-21 KD group displayed the most overt histologic signs of recovery, with axonal regeneration and the recovery of neuronal morphology at day 14 post-surgery. Significantly alleviation of TGF-ß1, TNF-α and IL-1ß was also found in sera from the miR-21 inhibition group in comparison to others, whereas BDNF gene expression was upregulated following miR-21 KD (p < 0.01). Further, significantly decreased AKT phosphorylation activity was illustrated in the miR-21 KD group (p < 0.001). The data suggest that miR-21 KD significantly reduces the inflammatory response at the damaged spinal cord site and promotes motor functional recovery. The treatment also elevated expression of BDNF, a neurotrophin participating in nerve regeneration.
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MicroARNs/genética , Regeneración Nerviosa/genética , Traumatismos de la Médula Espinal/terapia , Animales , Factor Neurotrófico Derivado del Encéfalo/genética , Citocinas/metabolismo , Femenino , Regulación de la Expresión Génica/genética , Técnicas de Silenciamiento del Gen , Terapia Genética/métodos , Ratones Endogámicos C57BL , Proteínas Proto-Oncogénicas c-akt/metabolismo , ARN Mensajero/genética , Transducción de Señal/fisiología , Médula Espinal/patología , Traumatismos de la Médula Espinal/patologíaRESUMEN
Characterized by bone mass loss, osteoporosis is an orthopedic disease typically found in postmenopausal women and aging individuals. Consistent with its pathogenesis summarized as an imbalance in bone formation/resorption, current pharmacologically therapeutic strategies for osteoporosis mainly aim to promote bone formation or/and inhibit bone resorption. However, few effective drugs with mild clinical side effects have been developed, making it a well-concerned issue to seek appropriate drugs for osteoporosis. In this study, we investigated the effect of ellagic acid (EA) on osteogenesis in vitro and in vivo and searched for its molecular mechanism. Here, we showed that EA promoted osteogenic differentiation of MSCs, increased mRNA and protein expression levels of osteoblast marker genes Runt-related transcription factor2, Osterix, Alkaline phosphatase, Collagen type I alpha 1, Osteopontin and Osteocalcin. Furthermore, ovariectomized mice with orally administered EA (10 mg/kg, 50 mg/kg) had significantly higher bone mass than those in controls. And experiments such as fluorescence double-labeling and enzyme-linked immunosorbent assay also demonstrated that EA could promote osteogenesis in vivo. To probe the molecular mechanism of EA, we performed RNA sequencing analysis using EA-treated BMSCs. Significant up-regulation of SMAD2/3 transcription factors was identified by RNA-seq, and it was confirmed in vitro that EA promoted bone formation by activating the SMAD2/3 signaling pathway. Evidence from our present experiments indicates that EA may be a promising candidate for clinical treatment for osteoporosis in future.
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Resorción Ósea , Células Madre Mesenquimatosas , Osteoporosis , Ratones , Femenino , Humanos , Animales , Osteogénesis , Ácido Elágico/farmacología , Osteoporosis/tratamiento farmacológico , Osteoporosis/etiología , Osteoblastos/metabolismo , Diferenciación Celular , Proteína Smad2/metabolismoRESUMEN
Osteoporosis is a common inflammaging-related condition, where long-term accumulation of pro-inflammatory cytokines causes massive bone loss. Periplocin, a cardiotonic steroid isolated from Periploca forrestii, has been proved to reduce inflammation in several inflammatory diseases, such as rheumatoid arthritis. However, its effect and mechanism of inflammation in osteoporosis, in which pro-inflammatory factors accelerate bone loss, has not been well demonstrated. In this study, periplocin attenuated receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclast differentiation of bone marrow-derived macrophages (BMMs) and RAW264.7 cells in vitro. It reduced osteoclast numbers and bone resorption in a concentration- and time-dependent manner. Further, periplocin treatment resulted in reduced bone loss on mice with ovariectomy-induced osteoporosis in vivo. By transcriptome sequencing, periplocin was indicated to function through inhibition of the mitogen-activated protein kinase (MAPK) and nuclear factor-κB (NF-κB) signaling pathways and attenuating interactions between NF-κB and nuclear factor of activated T-cells 1 (NFATc1). It was further detected to bind low density lipoprotein receptor-related protein 4 (LRP4) in osteoclasts to exert anti-inflammatory and anti-osteoclastic effects. Overall, the findings have highlighted a better understanding for the anti-inflammatory and anti-osteoclastic role of periplocin in osteoporosis and its mechanism, bringing new possibilities for osteoporosis treatment.
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Resorción Ósea , Osteoporosis , Animales , Femenino , Ratones , Antiinflamatorios/farmacología , Resorción Ósea/prevención & control , Resorción Ósea/metabolismo , Diferenciación Celular , Inflamación/metabolismo , FN-kappa B/metabolismo , Factores de Transcripción NFATC/genética , Factores de Transcripción NFATC/metabolismo , Osteoclastos , Osteogénesis , Osteoporosis/tratamiento farmacológico , Osteoporosis/prevención & control , Ligando RANK/farmacología , Receptores de LDL/metabolismoRESUMEN
ZnO nanoparticles in a spherical-like structure were synthesized via filtration and calcination methods, and different amounts of ZnO nanoparticles were added to MgH2 via ball milling. The SEM images revealed that the size of the composites was about 2 µm. The composites of different states were composed of large particles with small particles covering them. After the absorption and desorption cycle, the phase of composites changed. The MgH2-2.5 wt% ZnO composite reveals excellent performance among the three samples. The results show that the MgH2-2.5 wt% ZnO sample can swiftly absorb 3.77 wt% H2 in 20 min at 523 K and even at 473 K for 1 h can absorb 1.91 wt% H2. Meanwhile, the sample of MgH2-2.5 wt% ZnO can release 5.05 wt% H2 at 573 K within 30 min. Furthermore, the activation energies (Ea) of hydrogen absorption and desorption of the MgH2-2.5 wt% ZnO composite are 72.00 and 107.58 KJ/mol H2, respectively. This work reveals that the phase changes and the catalytic action of MgH2 in the cycle after the addition of ZnO, and the facile synthesis of the ZnO can provide direction for the better synthesis of catalyst materials.
RESUMEN
Osteoporosis is a common bone disease caused by an imbalance of bone resorption and formation that results in a loss of total bone density. SMAD2/3 signal transduction is known to play a crucial role in osteogenic differentiation through transforming growth factor-beta (TGF-ß). By screening a library of small-molecule compounds, the current study identifies higenamine (HG) as an active osteogenic agent that could be a therapeutic candidate for osteoporosis. In vitro data demonstrated that HG effectively induced expressions of osteogenic markers in mouse bone marrow stromal cell (BMSCs) and preosteoblastic cell cultures. Further, HG treatment resulted in enhanced bone formation and prevented accelerated bone loss on two animal models that mimic spontaneous senile osteoporosis and postmenopausal osteoporosis. IQ motif-containing GTPase-activating protein 1 (IQGAP1) was confirmed as a novel target of HG, where HG appears to bind to the Glu-1019 site of IQGAP1 to exert its osteogenic effects. Data subsequently suggested that HG promoted phosphorylation of SMAD2/3 and regulated the SMAD2/3 pathway by inhibiting SMAD4 ubiquitination. Overall, the findings highlight HG as a new small-molecule drug to promote bone formation through SMAD2/3 pathway in osteoporosis. © 2023 American Society for Bone and Mineral Research (ASBMR).
Asunto(s)
Osteogénesis , Osteoporosis , Ratones , Animales , Transducción de Señal , Diferenciación Celular , Osteoporosis/tratamiento farmacológico , Osteoporosis/metabolismo , EstrógenosRESUMEN
OBJECTIVE: Novel therapeutic strategies are emerging with the increased understanding of the underlying mechanisms of human osteosarcoma. This current study tends to decipher the potentially critical role of DEP domain-containing 1 (DEPDC1), a tumor-related gene, during the progression of osteosarcoma. METHODS: Bioinformatics analysis of 25,035 genes from the National Center for Biotechnology Information (NCBI) databases was performed to screen differentially expressed genes between osteosarcoma and normal control groups, complemented by the examination of 85 clinical osteosarcoma specimens. Furthermore, the manipulation of DEPDC1 expression levels by using silencing RNA (siRNA) or lentiviral vector intervention on human osteosarcoma cells was performed to reveal its role and interactions in in vitro and in vivo settings. RESULTS: Gene expression profile analysis and immunohistochemical (IHC) examination suggested that DEPDC1 is highly expressed in human osteosarcoma cells and tumor tissue. The silencing of DEPDC1 arrested osteosarcoma cell proliferation, promoted apoptosis, and ceased tumor metastasis. Studies involving clinical human osteosarcoma cases exhibited a strong correlation of DEPDC1 over-expressed osteosarcoma specimens with a reduced patient survival rate. CONCLUSIONS: Collectively, this study demonstrated that DEPDC1 is a critical driver in the promotion of osteosarcoma progression and results in poor patient prognosis. Genetically targeting or pharmacologically inhibiting DEPDC1 may serve as a promising strategy for treating human osteosarcoma.
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Neoplasias Óseas , Osteosarcoma , Humanos , Proteínas de Neoplasias/metabolismo , Proteínas Activadoras de GTPasa/genética , Proliferación Celular/genética , Perfilación de la Expresión Génica , Osteosarcoma/genética , Regulación Neoplásica de la Expresión Génica , Línea Celular Tumoral , Neoplasias Óseas/genéticaRESUMEN
BACKGROUND: Penfluridol, isolated from an FDA-approved small-molecule drug library as an inhibitor of tumor necrosis factor α (TNFα)-stimulated NF-κB activation, is clinically used to treat chronic schizophrenia and related disorders. This study is aimed to investigate the therapeutic effect of penfluridol on TNFα-stimulated inflammatory autoimmune diseases, particularly inflammatory arthritis. METHODS: Various in vitro studies to confirm the inhibitory effect of penfluridol on TNFα-induced NF-κB activity in bone marrow-derived macrophages or Raw 264.7 macrophage cell line. In vivo studies assessed the therapeutic effects of penfluridol in various disease models, including TNFα transgenic mice, collagen-induced arthritis, DSS-induced colitis, and TNBS-induced colitis. Identification and characterization of the binding of penfluridol to acid sphingomyelinase using bioinformatics and drug affinity responsive target stability assay. Acid sphingomyelinase activity assays to reveal penfluridol-mediated inhibition of acid sphingomyelinase activity. siRNA knockdown experiments to illustrate the dependence of penfluridol's anti-TNF activity on acid sphingomyelinase. RESULTS: Penfluridol effectively inhibited TNFα-induced NF-κB activation in vitro and alleviated the severity of arthritis and colitis in vivo. Mechanistic studies revealed that penfluridol bound to acid sphingomyelinase and inhibited its activation. In addition, knockdown of acid sphingomyelinase largely abolished the inhibitory effects of penfluridol on TNFα-induced inflammatory cytokine production. Furthermore, penfluridol suppressed the differentiation of spleen naive CD4+T cells to TH1 and TH17 and inhibited M1 macrophage polarization. CONCLUSION: This study provides the rationale for the possible innovative use of penfluridol as a newly identified small-molecule drug for TNFα-driven diseases, such as inflammatory arthritis and colitis.
Asunto(s)
Enfermedades Autoinmunes , Penfluridol , Animales , Enfermedades Autoinmunes/tratamiento farmacológico , Ratones , FN-kappa B/metabolismo , Esfingomielina Fosfodiesterasa , Inhibidores del Factor de Necrosis Tumoral , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
Objective: Fexofenadine (FFD) is an antihistamine drug with an anti-inflammatory effect. The intervertebral disc (IVD) degeneration process is involved in inflammation in which tumor necrosis factor-α (TNF-α) plays an important role. This study aims to investigate the role of FFD in the pathological process of IVD degeneration. Methods: Safranin O staining was used for the measurement of cartilageous tissue in the disc. Hematoxylin-Eosin (H&E) staining was used to determine the disc construction. A rat needle puncture model was taken advantage of to examine the role of FFD in disc degeneration in vivo. Western Blotting assay, immunochemistry, and immunoflurence staining were used for the determination of inflammatory molecules. ELISA assay was performed to detect the release of inflammatory cytokines. A real-time PCR assay was analyzed to determine the transcriptional expressions of molecules. Results: Elevated TNF-α resulted in inflammatory disc degeneration, while FFD protected against TNF-α-induced IVD degeneration. Mechanism study found FFD exhibited a disc protective effect through at least two pathways. (a) FFD inhibited TNF-α-mediated extracellular matrix (ECM) degradation and (b) FFD rescued TNF-α induced inflammation in disc degeneration. Furthermore, the present study found that FFD suppressed TNF-α mediated disc degeneration via the cPLA2/NF-κB signaling pathway. Conclusions: FFD provided another alternative for treating disc degeneration through a novel mechanism. Additionally, FFD may also be a potential target for the treatment of other inflammatory-related diseases, including IVD degeneration.
RESUMEN
Astrocytes are the most populous glial cells in the central nervous system (CNS). They are essential to CNS physiology and play important roles in the maintenance of homeostasis, development of synaptic plasticity, and neuroprotection. Nevertheless, under the influence of certain factors, astrocytes may also exert detrimental effects through a process of reactive astrogliosis. Previous studies have shown that astrocytes have more than one type of polarization. Two types have been extensively researched. One is a damaging change that occurs under inflammation and has been termed A1 astrocyte, while the other is a restorative change that occurs under ischemic induction and was termed A2 astrocyte. Researchers are now increasingly paying attention to the role of astrocytes in spinal cord injury (SCI), degenerative diseases, chronic pain, neurological tumors, and other CNS disorders. In this review, we discuss (a) the characteristics of polarized astrocytes, (b) the relationship between astrocyte polarization and SCI, and (c) new implications of reactive astrogliosis for future SCI therapies.
Asunto(s)
Progresión de la Enfermedad , Gliosis/complicaciones , Traumatismos de la Médula Espinal/complicaciones , Animales , Astrocitos/patología , Gliosis/genética , Gliosis/patología , Humanos , Transducción de Señal , Traumatismos de la Médula Espinal/genética , Traumatismos de la Médula Espinal/patologíaRESUMEN
Type 1 diabetes mellitus (T1DM) is an autoimmune disease characterized by insulin deficiency, and patients with diabetes have an increased risk of bone fracture and significantly impaired fracture healing. Proinflammatory cytokine tumor necrosis factor-alpha is significantly upregulated in diabetic fractures and is believed to underlie delayed fracture healing commonly observed in diabetes. Our previous genetic screen for the binding partners of progranulin (PGRN), a growth factor-like molecule that induces chondrogenesis, led to the identification of tumor necrosis factor receptors (TNFRs) as the PGRN-binding receptors. In this study, we employed several in vivo models to ascertain whether PGRN has therapeutic effects in diabetic fracture healing. Here, we report that deletion of PGRN significantly delayed bone fracture healing and aggravated inflammation in the fracture models of mice with T1DM. In contrast, recombinant PGRN effectively promoted diabetic fracture healing by inhibiting inflammation and enhancing chondrogenesis. In addition, both TNFR1 proinflammatory and TNFR2 anti-inflammatory signaling pathways are involved in PGRN-stimulated diabetic fracture healing. Collectively, these findings illuminate a novel understanding concerning the role of PGRN in diabetic fracture healing and may have an application in the development of novel therapeutic intervention strategies for diabetic and other types of impaired fracture healing.
Asunto(s)
Diabetes Mellitus Experimental/patología , Diabetes Mellitus Tipo 1/patología , Curación de Fractura/efectos de los fármacos , Progranulinas/farmacología , Animales , Condrogénesis/efectos de los fármacos , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Eliminación de Gen , Humanos , Inflamación/patología , Ratones , Progranulinas/deficiencia , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptores del Factor de Necrosis Tumoral/metabolismo , Proteínas Recombinantes/farmacología , Transducción de Señal/efectos de los fármacos , Serina-Treonina Quinasas TOR/metabolismo , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
BACKGROUND: Teriparatide, a 1-34 fragment of parathyroid hormone (PTH) that maintains most of the biological activities of PTH, has been employed since 2002 as an anabolic agent for osteoporotic individuals who are at high risk of fracture. The purpose of the present review is to provide a systematic summary and timely update on treatment with teriparatide for fracture prevention. METHODS: Electronic databases, including OVID MEDLINE, OVID Embase, and the Cochrane Library, were searched on February 9, 2018, to identify published systematic reviews and meta-analyses addressing treatment with teriparatide for fracture prevention, and A Measurement Tool to Assess Systematic Reviews 2 (AMSTAR 2) was used to assess the quality of included studies. RESULTS: Seventeen studies were included. Of the 17 eligible studies, 3 were rated as high quality, 3 were rated as moderate quality, 6 were rated as low quality, and 5 were rated as critically low quality. Teriparatide reduced vertebral and overall nonvertebral fractures in osteoporotic patients regardless of the existence of precipitating conditions, including postmenopausal status, glucocorticoid treatment, and chronic kidney disease, as compared with placebo, but not the site-specific nonvertebral fractures of the wrist and hip. Teriparatide did not more effectively reduce fracture risks when compared with other medications, such as bisphosphonates, selective estrogen receptor modulators, RANKL (receptor activator of nuclear factor kappa-beta ligand) inhibitor, or strontium ranelate. CONCLUSIONS: Teriparatide was safe and was not associated with an increased rate of adverse events when compared with other drugs. Teriparatide was effective for the prevention of vertebral and overall nonvertebral fractures in osteoporotic patients but not for the prevention of site-specific nonvertebral fractures at the wrist and hip. LEVEL OF EVIDENCE: Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.