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1.
Gene Ther ; 31(5-6): 324-334, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38627469

RESUMO

Glial cell line-derived neurotrophic factor (GDNF) protects dopaminergic neurons in various models of Parkinson's disease (PD). Cell-based GDNF gene delivery mitigates neurodegeneration and improves both motor and non-motor functions in PD mice. As PD is a chronic condition, this study aims to investigate the long-lasting benefits of hematopoietic stem cell (HSC)-based macrophage/microglia-mediated CNS GDNF (MMC-GDNF) delivery in an MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine) mouse model. The results indicate that GDNF treatment effectively ameliorated MPTP-induced motor deficits for up to 12 months, which coincided with the protection of nigral dopaminergic neurons and their striatal terminals. Also, the HSC-derived macrophages/microglia were recruited selectively to the neurodegenerative areas of the substantia nigra. The therapeutic benefits appear to involve two mechanisms: (1) macrophage/microglia release of GDNF-containing exosomes, which are transferred to target neurons, and (2) direct release of GDNF by macrophage/microglia, which diffuses to target neurons. Furthermore, the study found that plasma GDNF levels were significantly increased from baseline and remained stable over time, potentially serving as a convenient biomarker for future clinical trials. Notably, no weight loss, altered food intake, cerebellar pathology, or other adverse effects were observed. Overall, this study provides compelling evidence for the long-term therapeutic efficacy and safety of HSC-based MMC-GDNF delivery in the treatment of PD.


Assuntos
Modelos Animais de Doenças , Fator Neurotrófico Derivado de Linhagem de Célula Glial , Macrófagos , Microglia , Animais , Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Fator Neurotrófico Derivado de Linhagem de Célula Glial/genética , Camundongos , Macrófagos/metabolismo , Microglia/metabolismo , Masculino , Doença de Parkinson/terapia , Doença de Parkinson/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Camundongos Endogâmicos C57BL , Neurônios Dopaminérgicos/metabolismo , Terapia Genética/métodos , Transplante de Células-Tronco Hematopoéticas/métodos , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina , Exossomos/metabolismo , Substância Negra/metabolismo
2.
Glia ; 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38899731

RESUMO

Spinal cord injury (SCI) can result in severe motor and sensory deficits, for which currently no effective cure exists. The pathological process underlying this injury is extremely complex and involves many cell types in the central nervous system. In this study, we have uncovered a novel function for macrophage G protein-coupled receptor kinase-interactor 1 (GIT1) in promoting remyelination and functional repair after SCI. Using GIT1flox/flox Lyz2-Cre (GIT1 CKO) mice, we identified that GIT1 deficiency in macrophages led to an increased generation of tumor necrosis factor-alpha (TNFα), reduced proportion of mature oligodendrocytes (mOLs), impaired remyelination, and compromised functional recovery in vivo. These effects in GIT1 CKO mice were reversed with the administration of soluble TNF inhibitor. Moreover, bone marrow transplantation from GIT1 CWT mice reversed adverse outcomes in GIT1 CKO mice, further indicating the role of macrophage GIT1 in modulating spinal cord injury repair. Our in vitro experiments showed that macrophage GIT1 plays a critical role in secreting TNFα and influences the differentiation of oligodendrocyte precursor cells (OPCs) after stimulation with myelin debris. Collectively, our data uncovered a new role of macrophage GIT1 in regulating the transformation of OPCs into mOLs, essential for functional remyelination after SCI, suggesting that macrophage GIT1 could be a promising treatment target of SCI.

3.
J Nanobiotechnology ; 21(1): 452, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38012616

RESUMO

BACKGROUND: Spinal cord injury (SCI) remains a significant health concern, with limited available treatment options. This condition poses significant medical, economic, and social challenges. SCI is typically categorized into primary and secondary injuries. Inflammation, oxidative stress, scar formation, and the immune microenvironment impede axon regeneration and subsequent functional restoration. Numerous studies have shown that the destruction of the blood-brain barrier (BBB) and microvessels is a crucial factor in severe secondary injury. Additionally, reactive oxygen species (ROS)-induced lipid peroxidation significantly contributes to endothelial cell death. Pericytes are essential constituents of the BBB that share the basement membrane with endothelial cells and astrocytes. They play a significant role in the establishment and maintenance of BBB. RESULTS: Immunofluorescence staining at different time points revealed a consistent correlation between pericyte coverage and angiogenesis, suggesting that pericytes promote vascular repair via paracrine signaling. Pericytes undergo alterations in cellular morphology and the transcriptome when exposed to hypoxic conditions, potentially promoting angiogenesis. We simulated an early ischemia-hypoxic environment following SCI using glucose and oxygen deprivation and BBB models. Co-culturing pericytes with endothelial cells improved barrier function compared to the control group. However, this enhancement was reduced by the exosome inhibitor, GW4869. In vivo injection of exosomes improved BBB integrity and promoted motor function recovery in mice following SCI. Subsequently, we found that pericyte-derived exosomes exhibited significant miR-210-5p expression based on sequencing analysis. Therefore, we performed a series of gain- and loss-of-function experiments in vitro. CONCLUSION: Our findings suggest that miR-210-5p regulates endothelial barrier function by inhibiting JAK1/STAT3 signaling. This process is achieved by regulating lipid peroxidation levels and improving mitochondrial function, suggesting a potential mechanism for restoration of the blood-spinal cord barrier (BSCB) after SCI.


Assuntos
MicroRNAs , Traumatismos da Medula Espinal , Camundongos , Animais , Pericitos/metabolismo , Células Endoteliais/metabolismo , Peroxidação de Lipídeos , Axônios , Regeneração Nervosa , Traumatismos da Medula Espinal/metabolismo , Transdução de Sinais , MicroRNAs/genética , MicroRNAs/metabolismo
4.
Bioorg Chem ; 129: 106192, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36265355

RESUMO

Capsid assembly modulators (CAMs) represent a novel class of antiviral agents targeting hepatitis B virus (HBV) capsid to disrupt the assembly process. NVR 3-778 is the first CAM to demonstrate antiviral activity in patients infected with HBV. However, the relatively low aqueous solubility and moderate activity in the human body halted further development of NVR 3-778. To improve the anti-HBV activity and the drug-like properties of NVR 3-778, we designed and synthesized a series of NVR 3-778 derivatives. Notably, phenylboronic acid-bearing compound 7b (EC50 = 0.83 ± 0.33 µM, CC50 = 19.4 ± 5.0 µM) displayed comparable anti-HBV activity to NVR 3-778 (EC50 = 0.73 ± 0.20 µM, CC50 = 23.4 ± 7.0 µM). Besides, 7b showed improved water solubility (328.8 µg/mL, pH 7) compared to NVR 3-778 (35.8 µg/mL, pH 7). Size exclusion chromatography (SEC) and quantification of encapsidated viral RNA were used to demonstrate that 7b behaves as a class II CAM similar to NVR 3-778. Moreover, molecular dynamics (MD) simulations were conducted to rationalize the structure-activity relationships (SARs) of these novel derivatives and to understand their key interactions with the binding pocket, which provide useful indications for guiding the further rational design of more effective anti-HBV drugs.


Assuntos
Antivirais , Benzamidas , Capsídeo , Desenho de Fármacos , Vírus da Hepatite B , Montagem de Vírus , Humanos , Antivirais/síntese química , Antivirais/química , Antivirais/farmacologia , Benzamidas/síntese química , Benzamidas/química , Benzamidas/farmacologia , Capsídeo/efeitos dos fármacos , Capsídeo/metabolismo , Proteínas do Capsídeo/metabolismo , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/fisiologia , Montagem de Vírus/efeitos dos fármacos
5.
J Nanobiotechnology ; 20(1): 56, 2022 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-35093078

RESUMO

Subtalar osteoarthritis (STOA) is often secondary to chronic ankle sprains, which seriously affects the quality of life of patients. Due to its etiology and pathogenesis was not studied equivocally yet, there is currently a lack of effective conservative treatments. Although they have been used for tissue repair, platelet-rich plasma-derived exosomes (PRP-Exo) have the disadvantage of low retention and short-lived therapeutic effects. This study aimed to determine whether incorporation of PRP-Exo in thermosensitive hydrogel (Gel) increased their retention in the joint and thereby playing a therapeutic role on STOA due to chronic mechanical instability established by transecting lateral ligaments (anterior talofibular ligament (ATFL)/calcaneal fibular ligament (CFL)). PRP-Exo incorporated Gel (Exo-Gel) system, composed of Poloxamer-407 and 188 mixture-based thermoresponsive hydrogel matrix in an optimal ratio, was determined by its release ability of Exo and rheology of Gel response to different temperature. The biological activity of Exo-Gel was evaluated in vitro, and the therapeutic effect of Exo-Gel on STOA was evaluated in vivo. Exo released from Exo-Gel continuously for 28 days could promote the proliferation and migration of mouse bone mesenchymal stem cells (mBMSCs) and chondrocytes, at the same time enhance the chondrogenic differentiation of mBMSCs, and inhibit inflammation-induced chondrocyte degeneration. In vivo experiments confirmed that Exo-Gel increased the local retention of Exo, inhibited the apoptosis and hypertrophy of chondrocytes, enhanced their proliferation, and potentially played the role in stem cell recruitment to delay the development of STOA. Thus, Delivery of PRP-Exo incorporated in thermosensitive Gel provides a novel approach of cell-free therapy and has therapeutic effect on STOA.


Assuntos
Exossomos , Osteoartrite , Plasma Rico em Plaquetas , Animais , Cartilagem/metabolismo , Exossomos/metabolismo , Humanos , Camundongos , Osteoartrite/metabolismo , Plasma Rico em Plaquetas/metabolismo , Qualidade de Vida
6.
Molecules ; 27(21)2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36364467

RESUMO

The AIDS pandemic is still of importance. HIV-1 and HIV-2 are the causative agents of this pandemic, and in the absence of a viable vaccine, drugs are continually required to provide quality of life for infected patients. The HIV capsid (CA) protein performs critical functions in the life cycle of HIV-1 and HIV-2, is broadly conserved across major strains and subtypes, and is underexploited. Therefore, it has become a therapeutic target of interest. Here, we report a novel series of 2-pyridone-bearing phenylalanine derivatives as HIV capsid modulators. Compound FTC-2 is the most potent anti-HIV-1 compound in the new series of compounds, with acceptable cytotoxicity in MT-4 cells (selectivity index HIV-1 > 49.57; HIV-2 > 17.08). However, compound TD-1a has the lowest EC50 in the anti-HIV-2 assays (EC50 = 4.86 ± 1.71 µM; CC50= 86.54 ± 29.24 µM). A water solubility test found that TD-1a showed a moderately increased water solubility compared with PF74, while the water solubility of FTC-2 was improved hundreds of times. Furthermore, we use molecular simulation studies to provide insight into the molecular contacts between the new compounds and HIV CA. We also computationally predict drug-like properties and metabolic stability for FTC-2 and TD-1a. Based on this analysis, TD-1a is predicted to have improved drug-like properties and metabolic stability over PF74. This study increases the repertoire of CA modulators and has important implications for developing anti-HIV agents with novel mechanisms, especially those that inhibit the often overlooked HIV-2.


Assuntos
Fármacos Anti-HIV , HIV-1 , Humanos , Capsídeo , Fenilalanina , Qualidade de Vida , Replicação Viral , HIV-1/metabolismo , Proteínas do Capsídeo/metabolismo , HIV-2/metabolismo , Água/metabolismo , Relação Estrutura-Atividade
7.
Molecules ; 27(18)2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36144715

RESUMO

Hepatitis B virus (HBV) capsid protein (Cp) is necessary for viral replication and the maintenance of viral persistence, having become an attractive target of anti-HBV drugs. To improve the water solubility of HBV capsid protein allosteric modulator (CpAM) NVR 3-778, a series of novel carboxylic acid and phosphate prodrugs were designed and synthesized using a prodrug strategy. In vitro HBV replication assay showed that these prodrugs maintained favorable antiviral potency (EC50 = 0.28−0.42 µM), which was comparable to that of NVR 3-778 (EC50 = 0.38 µM). More importantly, the cytotoxicity of prodrug N8 (CC50 > 256 µM) was significantly reduced compared to NVR 3-778 (CC50 = 13.65 ± 0.21 µM). In addition, the water solubility of prodrug N6 was hundreds of times better than that of NVR 3-778 in three phosphate buffers with various pH levels (2.0, 7.0, 7.4). In addition, N6 demonstrated excellent plasma and blood stability in vitro and good pharmacokinetic properties in rats. Finally, the hemisuccinate prodrug N6 significantly improved the candidate drug NVR 3-778's water solubility and increased metabolic stability while maintaining its antiviral efficacy.


Assuntos
Vírus da Hepatite B , Pró-Fármacos , Animais , Antivirais/química , Benzamidas , Proteínas do Capsídeo/química , Ácidos Carboxílicos/metabolismo , Ácidos Carboxílicos/farmacologia , Vírus da Hepatite B/metabolismo , Fosfatos/metabolismo , Piperidinas , Pró-Fármacos/química , Ratos , Água/metabolismo
8.
J Environ Sci (China) ; 116: 125-138, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35219410

RESUMO

Petrochemical enterprises have become a major source of global greenhouse gas (GHG) emissions. Yet, due to the unavailability of basic data, there is still a lack of case studies to quantify GHG emissions and provide petrochemical enterprises with guidelines for implementing energy conservation and emission reduction strategies. Therefore, this study conducted a life cycle assessment (LCA) analysis to estimate the GHG emissions of four typical petrochemical enterprises in China, using first-hand data, to determine possible emission reduction measures. The analytical data revealed that Dushanzi Petrochemical (DSP) has the highest GHG emission intensity (1.17 tons CO2e/ton), followed by Urumqi Petrochemical (UP) (1.08 tons CO2e/ton), Dalian Petrochemical (DLP) (average 0.58 tons CO2e/ton) and Karamay Petrochemical (KP) (average 0.50 tons CO2e/ton) over the whole life cycle. At the same time, GHG emissions during fossil fuel combustion were the largest contributor to the whole life cycle, accounting for about 77.31%-94.27% of the total emissions. In the fossil-fuel combustion phase, DSP had the highest unit GHG emissions (1.20 tons CO2e), followed by UP (0.89 tons CO2e). In the industrial production phase, DLP had the highest unit GHG emissions (average 0.13 tons CO2e/ton), followed by UP (0.10 tons CO2e/ton). During the torch burning phase, torch burning under accident conditions was the main source of GHG emissions. It is worth noting that the CO2 recovery stage has "negative value," indicating that it will bring some environmental benefits. Further scenario analysis shows that effective policies and advanced technologies can further reduce GHG emissions.


Assuntos
Gases de Efeito Estufa , China , Efeito Estufa , Gases de Efeito Estufa/análise , Indústrias
9.
FASEB J ; 34(2): 2055-2074, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31908016

RESUMO

In spinal cord ischemia-reperfusion (I/R) injury, large amounts of reactive oxygen species can cause mitochondrial damage. Therefore, mitophagy acts as the main mechanism for removing damaged mitochondria and protects nerve cells. This study aimed to illustrate the important role of GPCR kinase 2-interacting protein-1 (GIT1) in mitophagy in vivo and in vitro. The level of mitophagy in the neurons of Git1 knockout mice was significantly reduced after ischemia-reperfusion. However, the overexpression of adeno-associated virus with Git1 promoted mitophagy and inhibited the apoptosis of neurons. GIT1 regulated the phosphorylation of Beclin-1 in Thr119, which could promote the translocation of Parkin to the mitochondrial outer membrane. This process was independent of PTEN-induced kinase 1 (PINK1), but it could not rescue the role in the absence of PINK1. Overall, GIT1 enhanced mitophagy and protected neurons against ischemia-reperfusion injury and, hence, might serve as a new research site for the protection of ischemia-reperfusion injury.


Assuntos
Proteína Beclina-1/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas Ativadoras de GTPase/metabolismo , Mitofagia , Traumatismo por Reperfusão , Doenças da Medula Espinal , Ubiquitina-Proteína Ligases/metabolismo , Animais , Proteína Beclina-1/genética , Proteínas de Ciclo Celular/genética , Proteínas Ativadoras de GTPase/genética , Camundongos , Camundongos Knockout , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/prevenção & controle , Doenças da Medula Espinal/genética , Doenças da Medula Espinal/metabolismo , Doenças da Medula Espinal/patologia , Doenças da Medula Espinal/prevenção & controle , Ubiquitina-Proteína Ligases/genética
10.
J Neuroinflammation ; 17(1): 47, 2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-32019561

RESUMO

BACKGROUND: Spinal cord injury (SCI) can lead to severe motor and sensory dysfunction with high disability and mortality. In recent years, mesenchymal stem cell (MSC)-secreted nano-sized exosomes have shown great potential for promoting functional behavioral recovery following SCI. However, MSCs are usually exposed to normoxia in vitro, which differs greatly from the hypoxic micro-environment in vivo. Thus, the main purpose of this study was to determine whether exosomes derived from MSCs under hypoxia (HExos) exhibit greater effects on functional behavioral recovery than those under normoxia (Exos) following SCI in mice and to seek the underlying mechanism. METHODS: Electron microscope, nanoparticle tracking analysis (NTA), and western blot were applied to characterize differences between Exos and HExos group. A SCI model in vivo and a series of in vitro experiments were performed to compare the therapeutic effects between the two groups. Next, a miRNA microarray analysis was performed and a series of rescue experiments were conducted to verify the role of hypoxic exosomal miRNA in SCI. Western blot, luciferase activity, and RNA-ChIP were used to investigate the underlying mechanisms. RESULTS: Our results indicate that HExos promote functional behavioral recovery by shifting microglial polarization from M1 to M2 phenotype in vivo and in vitro. A miRNA array showed miR-216a-5p to be the most enriched in HExos and potentially involved in HExos-mediated microglial polarization. TLR4 was identified as the target downstream gene of miR-216a-5p and the miR-216a-5p/TLR4 axis was confirmed by a series of gain- and loss-of-function experiments. Finally, we found that TLR4/NF-κB/PI3K/AKT signaling cascades may be involved in the modulation of microglial polarization by hypoxic exosomal miR-216a-5p. CONCLUSION: Hypoxia preconditioning represents a promising and effective approach to optimize the therapeutic actions of MSC-derived exosomes and a combination of MSC-derived exosomes and miRNAs may present a minimally invasive method for treating SCI.


Assuntos
Exossomos/metabolismo , Células-Tronco Mesenquimais/metabolismo , MicroRNAs/metabolismo , Microglia/metabolismo , Traumatismos da Medula Espinal/terapia , Animais , Polaridade Celular/fisiologia , Camundongos , Recuperação de Função Fisiológica/fisiologia , Traumatismos da Medula Espinal/metabolismo
11.
J Neuroinflammation ; 17(1): 62, 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-32066456

RESUMO

BACKGROUND: A sustained inflammatory response following spinal cord injury (SCI) contributes to neuronal damage, inhibiting functional recovery. Macrophages, the major participants in the inflammatory response, transform into foamy macrophages after phagocytosing myelin debris, subsequently releasing inflammatory factors and amplifying the secondary injury. Here, we assessed the effect of macrophage scavenger receptor 1 (MSR1) in phagocytosis of myelin debris after SCI and explained its possible mechanism. METHODS: The SCI model was employed to determine the critical role of MSR1 in phagocytosis of myelin debris in vivo. The potential functions and mechanisms of MSR1 were explored using qPCR, western blotting, and immunofluorescence after treating macrophages and RAW264.7 with myelin debris in vitro. RESULTS: In this study, we found improved recovery from traumatic SCI in MSR1-knockout mice over that in MSR1 wild-type mice. Furthermore, MSR1 promoted the phagocytosis of myelin debris and the formation of foamy macrophage, leading to pro-inflammatory polarization in vitro and in vivo. Mechanistically, in the presence of myelin debris, MSR1-mediated NF-κB signaling pathway contributed to the release of inflammatory mediators and subsequently the apoptosis of neurons. CONCLUSIONS: Our study elucidates a previously unrecognized role of MSR1 in the pathophysiology of SCI and suggests that its inhibition may be a new treatment strategy for this traumatic condition.


Assuntos
Apoptose/fisiologia , Macrófagos/metabolismo , Neurônios/metabolismo , Receptores Depuradores Classe A/deficiência , Traumatismos da Medula Espinal/metabolismo , Animais , Células Cultivadas , Macrófagos/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurônios/patologia , Células RAW 264.7 , Receptores Depuradores Classe A/genética , Traumatismos da Medula Espinal/patologia
12.
Med Sci Monit ; 26: e920766, 2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32312946

RESUMO

BACKGROUND Osteosarcoma is the most common primary tumor of bone. Interleukin-33 (IL-33) is a pro-inflammatory cytokine that also participates in tumor progression. This study aimed to investigate the role of IL-33 in human osteosarcoma cell viability, proliferation, apoptosis, and epithelial-mesenchymal transition (EMT) in vitro and the molecular mechanisms involved. MATERIAL AND METHODS The normal osteoblast cell line, hFOB 1.19, and the human osteosarcoma cell lines SOSP-9607, SAOS2, MG63, and U2OS were studied. The expression of IL-33 mRNA and protein in human osteosarcoma cell lines were detected using quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot, respectively. The effects of IL-33 on human osteosarcoma cell viability, apoptosis, EMT, and the signaling pathways were studied using the MTT assay, flow cytometry, qRT-PCR, and Western blot. RESULTS IL-33 was upregulated in human osteosarcoma cell lines, including U2OS cells. The use of an IL-33 gene plasmid promoted osteosarcoma cell viability, inhibited cell apoptosis, increased the expression of Bcl-2, and reduced the expression of Bax. IL-33 reduced the level of E-cadherin and increased the levels of N-cadherin and matrix metalloproteinase-9 (MMP-9) in osteosarcoma cells at the mRNA and protein level. The use of the IL-33 plasmid increased the protein expression levels of p-AKT and the p-AKT/AKT ratio in osteosarcoma cells, and IL-33 siRNA reversed these findings. CONCLUSIONS IL-33 was highly expressed in human osteosarcoma cells. Down-regulation of IL-33 reduced cell viability and EMT of osteosarcoma cells, and induced cell apoptosis through activation of the PI3K/AKT signaling pathway.


Assuntos
Neoplasias Ósseas/metabolismo , Interleucina-33/metabolismo , Osteossarcoma/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Apoptose/fisiologia , Neoplasias Ósseas/genética , Neoplasias Ósseas/patologia , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Sobrevivência Celular/fisiologia , Transição Epitelial-Mesenquimal , Humanos , Interleucina-33/biossíntese , Interleucina-33/genética , Osteoblastos/citologia , Osteoblastos/metabolismo , Osteossarcoma/genética , Osteossarcoma/patologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais , Regulação para Cima
13.
J Environ Manage ; 265: 110350, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32421549

RESUMO

The existence of leachable Cr(Ⅵ) in chromite ore processing residue (COPR) makes it hazardous waste. Therefore, resourceful utilization of COPR is necessary to protect the ecosystem and living biota from hazardous effect of Cr(Ⅵ) caused by its leaching. In this study, detoxification and immobilization of COPR was carried out through introduction of ascorbic acid (AA) in alkali-activated cementitious materials. Several dosages of AA were treated with water extractable/soluble Cr(Ⅵ) to achieve the optimum dosage which could be further utilized in solidification process. While, the compressive strength was developed through utilizing different modulus of water glass, liquid to solid ratios and curing temperatures. The results showed that 0.3% of AA was enough to reduce the Cr(Ⅵ) into Cr(Ⅲ), and highest compressive strength of 120 MPa was achieved after using the modulus of 1.6, liquid to solid ratio of 0.24 and curing temperature of 30 °C. The solidified samples having AA had not exceeded the toxicity limit up to 60% addition of COPR, and samples without addition of AA were effective for solidification of 20% COPR. Regarding mechanism, the compressive strength, leaching behavior and microscopic analysis i.e. X-ray diffraction (XRD), Fourier transform infrared spectrometry (FTIR) and scanning electron microscope with energy dispersive spectrometry (SEM-EDS) showed that immobilization of chromium was carried out through physical and chemical means.


Assuntos
Álcalis , Resíduos Industriais , Ácido Ascórbico , Cromo , Ecossistema
14.
J Cell Biochem ; 120(3): 3401-3414, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30368870

RESUMO

Ligamentum flavum (LF)-derived mesenchymal stem cells (MSCs) have been implicated in the pathogenesis of calcification of the ligamentum flavum (CLF) leading to the increased presence of chondrocyte-like cells and calcium deposition in CLF; however, the mechanisms of LF-MSCs in differentiation are not defined. In this study, we investigated the role of antidifferentiation noncoding RNA (ANCR) in the differentiation of LF-MSCs. We found that ANCR was downregulated in human CLF tissues. In cultured LF-MSCs, ANCR downregulation led to decreased cell proliferation but enhanced chondrogenic differentiation and calcification. In contract, ANCR overexpression increased cell proliferation but inhibited differentiation and calcification. Mechanistically, we detected a positive correlation between ANCR and enhancer of zeste homolog 2 (EZH2) in human CLF tissues. In cultured LF-MSCs, ANCR knockdown decreased while ANCR overexpression increased EZH2 expression. In addition, physical association between ANCR and EZH2 was revealed by an RNA pull-down assay. Functionally, EZH2 overexpression prevented chondrogenic differentiation and calcification enhanced by ANCR knockdown. These findings indicated that ANCR upregulates EZH2 expression and physically binds to EZH2 in LF-MSCs to suppress chondrogenic differentiation and calcification. Therefore, downregulated ANCR contributes to increasing of chondrocyte-like cells and calcium deposition in CLF. ANCR may serve as a therapeutic target for CLF.


Assuntos
Calcificação Fisiológica , Diferenciação Celular , Condrócitos/citologia , Condrogênese , Ligamento Amarelo/fisiologia , Células-Tronco Mesenquimais/fisiologia , RNA Longo não Codificante/genética , Proliferação de Células , Células Cultivadas , Condrócitos/metabolismo , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Humanos , Ligamento Amarelo/citologia , Células-Tronco Mesenquimais/citologia
15.
Exp Cell Res ; 367(2): 119-131, 2018 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-29601800

RESUMO

Ossification of the ligamentum flavum (OLF) is a debilitating disease resulting from the development of ectopic bone formation, which leads to the compression of the spinal cord. Nicotinamide phosphoribosyltransferase (NAMPT) was found to be upregulated and microRNA-182 (miR-182) was downregulated in OLF tissue. We investigated the effects of NAMPT and miR-182 expression in OLF cells and the influence on proteins associated with osteogenic differentiation. MiR-182 overexpression inhibited NAMPT, RUNX2, OCN and OPN mRNA and protein expression in OLF cells. Alkaline phosphatase (ALP) assay and Alizarin red staining confirmed reduced levels of osteogenic differentiation and mineralized nodule formation. Knockdown of NAMPT and the NAMPT inhibitor FK866 also inhibits RUNX2, OCN and OPN mRNA expression and protein levels, whereas overexpression of NAMPT promotes the expression of RUNX2, OCN and OPN and the generation of bone nodules. Dual-luciferase reporter assays revealed that miR-182 directly targets NAMPT and downregulates its expression. Transfection of OLF cells with miR-182 downregulated NAMPT and suppressed the regulation of RUNX2, OCN, and OPN by NAMPT overexpression. Overall, these data demonstrate that miR-182 suppresses OLF by downregulating NAMPT.


Assuntos
Citocinas/genética , Ligamento Amarelo/patologia , MicroRNAs/metabolismo , Nicotinamida Fosforribosiltransferase/genética , Ossificação Heterotópica/genética , Células Cultivadas , Citocinas/antagonistas & inibidores , Citocinas/metabolismo , Regulação da Expressão Gênica , Humanos , Nicotinamida Fosforribosiltransferase/antagonistas & inibidores , Nicotinamida Fosforribosiltransferase/metabolismo , Ossificação Heterotópica/metabolismo , Ossificação Heterotópica/patologia
16.
Biochem Biophys Res Commun ; 503(4): 2749-2757, 2018 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-30093112

RESUMO

Blocking aerobic glycolysis has been proposed as an attractive therapeutic strategy for impairing the proliferation of cancer cells. However, the underlying mechanisms are poorly understood. Here, we show that miR-15b-5p was downregulated in osteosarcoma (OS) and that lower expression of miR-15b-5p promoted proliferation and contributed to the Warburg effect in OS cells. Mechanistically, miR-15b-5p acted as a tumor suppressor in OS by directly targeting pyruvate dehydrogenase kinase-4 and inhibiting its expression. These results reveal a previously unknown function of miR-15b-5p in OS, which is associated with metabolic alterations that promote cancer progression. miR-15b-5p may play an essential role in the molecular therapy of patients with OS.


Assuntos
Neoplasias Ósseas/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Osteoblastos/metabolismo , Osteossarcoma/genética , Proteínas Serina-Treonina Quinases/genética , Regiões 3' não Traduzidas , Animais , Apoptose , Sequência de Bases , Sítios de Ligação , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/mortalidade , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Proliferação de Células , Glicólise/genética , Humanos , Masculino , Camundongos , Camundongos Nus , MicroRNAs/metabolismo , Osteoblastos/patologia , Osteossarcoma/metabolismo , Osteossarcoma/mortalidade , Osteossarcoma/patologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/metabolismo , Piruvato Desidrogenase Quinase de Transferência de Acetil , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Transdução de Sinais , Análise de Sobrevida , Ensaios Antitumorais Modelo de Xenoenxerto
17.
J Environ Qual ; 46(1): 64-71, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28177404

RESUMO

Spatiotemporal patterns of forest carbon (C) sinks and accurate estimation of such patterns are crucial to sustainable forest management. We combined individual tree biomass equations and a Random Forest algorithm to assess the spatiotemporal changes in biomass C sequestration and to further quantify the relative contributions of forest areal expansion and growth to biomass C sinks in Sichuan Province, China, over the past 25 yr. Forest area and average biomass C density increased from 10.5 million ha and 45.7 Mg C ha in 1988 to 14.2 million ha and 52.3 Mg C ha in 2012. Average C density was generally larger in the north and west of Sichuan Province compared with other regions. The expanded forest area and enhanced C density have jointly led to a rise in total C storage by 54.9% over this period in Sichuan Province. It was estimated that the forest areal expansion has been a larger contributor to C sinks than forest growth in Sichuan Province (69 vs. 31%), especially in the regions of the northwestern high mountains and the hilly country of the Sichuan basin. However, the relative contributions of areal expansion exhibited different trends in five subregions and 15 forest species groups in this province. Our study suggests that it is necessary to develop a new forestry management mode to maintain the long-term health of forest ecosystems in Sichuan Province, which should attach more importance to improving forest quality and selecting tree species in different subregions while increasing forested area in the future.


Assuntos
Sequestro de Carbono , Ecossistema , Árvores , Biomassa , Carbono , China
18.
World J Surg Oncol ; 13: 37, 2015 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-25889820

RESUMO

BACKGROUND: Intracranial meningioma and glioma collision tumors are relatively uncommon and are even more rarely located within the ventricles. CASE PRESENTATION: Here, we report a case of a patient with an intraventricular meningioma and astrocytoma collision tumor. A 39-year-old man previously underwent excision of an astrocytoma in the triangle area of the lateral ventricle and exhibited good post-surgery recovery. The astrocytoma recurred in situ six years after the surgery, and the case was complicated by a malignant meningioma. The patient recovered well after surgery to treat the recurrence and was administered radiotherapy after discharge. In addition to reporting on this case, we conducted a literature review of collision tumors; based on this review, we propose several hypotheses regarding the formation of collision tumors. CONCLUSIONS: We conclude that a possible cause of the collision tumor formation between the intracranial meningioma and the astrocytoma was the recurrence of an astrocytoma-induced malignancy of the arachnoid cells in the choroid plexus.


Assuntos
Astrocitoma/complicações , Neoplasias Encefálicas/complicações , Neoplasias do Ventrículo Cerebral/complicações , Neoplasias Meníngeas/complicações , Meningioma/complicações , Recidiva Local de Neoplasia/etiologia , Adulto , Astrocitoma/patologia , Astrocitoma/cirurgia , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/cirurgia , Neoplasias do Ventrículo Cerebral/patologia , Neoplasias do Ventrículo Cerebral/cirurgia , Humanos , Masculino , Neoplasias Meníngeas/patologia , Neoplasias Meníngeas/cirurgia , Meningioma/patologia , Meningioma/cirurgia , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/radioterapia , Prognóstico
19.
RSC Adv ; 14(2): 1377-1385, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38174258

RESUMO

Chromite ore processing residue (COPR) is a hazardous waste because of leachable chromium, especially Cr(vi). Therefore, ascorbic acid (AA) and blast furnace slag (BFS) have been used to detoxify and solidify COPR. On this basis, environmental stability experiments with high temperature and freeze-thaw cycles were carried out to explore the stability performance of a solidified body with 40% COPR. The environmental stability performance was analyzed through changes in edge length, mass loss, compressive strength development, and leaching concentration of Cr(vi). The result indicated that the high-temperature environment had much more effect on the solidified body than the freeze-thaw cycle environment in these four aspects: after being maintained at 900 °C for 2 h, the compressive strength of the solidified bodies reached its minimum value (35.76 MPa). However, in the freeze-thaw cycle experiments, the compressive strength of the solidified bodies consistently remained above 80 MPa, and the leaching of hexavalent chromium was below the limit (5 mg L-1). In addition, X-ray diffraction (XRD) and Fourier transform infrared spectrometry (FTIR) analysis verified that COPR was effectively solidified through physical and chemical means. Moreover, high temperature changes the molecular structure of the solidified body, thus reducing the compressive strength and curing ability of the solidified body, while the freeze-thaw cycle experiment has little effect on it.

20.
Front Oncol ; 14: 1309842, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38410113

RESUMO

Background: Bladder cancer is a common malignant tumor of the urinary system. The progression of the condition is associated with a poor prognosis, so it is necessary to identify new biomarkers to improve the diagnostic rate of bladder cancer. Methods: In this study, 338 urine samples (144 bladder cancer, 123 healthy control, 32 cystitis, and 39 upper urinary tract cancer samples) were collected, among which 238 samples (discovery group) were analyzed by LC-MS. The urinary proteome characteristics of each group were compared with those of bladder cancer, and the differential proteins were defined by bioinformatics analysis. The pathways and functional enrichments were annotated. The selected proteins with the highest AUC score were used to construct a diagnostic panel. One hundred samples (validation group) were used to test the effect of the panel by ELISA. Results: Compared with the healthy control, cystitis and upper urinary tract cancer samples, the number of differential proteins in the bladder cancer samples was 325, 158 and 473, respectively. The differentially expressed proteins were mainly related to lipid metabolism and iron metabolism and were involved in the proliferation, metabolism and necrosis of bladder cancer cells. The AUC of the panel of APOL1 and ITIH3 was 0.96 in the discovery group. ELISA detection showed an AUC of 0.92 in the validation group. Conclusion: This study showed that urinary proteins can reflect the pathophysiological changes in bladder cancer and that important molecules can be used as biomarkers for bladder cancer screening. These findings will benefit the application of the urine proteome in clinical research.

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