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1.
Exp Cell Res ; 437(1): 113998, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38513962

RESUMO

Plasma saturated free fatty acid (FFA)-induced endothelial dysfunction (ED) contributes to the pathogenesis of atherosclerosis and cardiovascular diseases. However, the mechanism underlying saturated FFA-induced ED remains unclear. This study demonstrated that palmitic acid (PA) induced ED by activating the NADPH oxidase (NOX)/ROS signaling pathway to activate protein phosphatase 4 (PP4) and protein phosphatase 2A (PP2A), thereby reducing endothelial nitric oxide synthase (eNOS) phosphorylation at Ser633 and Ser1177, respectively. Okadaic acid (OA) and fostriecin (FST), which are inhibitors of PP2A, inhibited the PA-induced decreases in eNOS phosphorylation at Ser633 and Ser1177. The antioxidants N-acetylcysteine (NAC) and apocynin (APO) or knockdown of gp91phox or p67phox (NOX subunits) restored PA-mediated downregulation of PP4R2 protein expression and eNOS Ser633 phosphorylation. Knockdown of the PP4 catalytic subunit (PP4c) specifically increased eNOS Ser633 phosphorylation, while silencing the PP2A catalytic subunit (PP2Ac) restored only eNOS Ser1177 phosphorylation. Furthermore, PA dramatically decreased the protein expression of the PP4 regulatory subunit R2 (PP4R2) but not the other regulatory subunits. PP4R2 overexpression increased eNOS Ser633 phosphorylation, nitric oxide (NO) production, cell migration and tube formation but did not change eNOS Ser1177 phosphorylation levels. Coimmunoprecipitation (Co-IP) suggested that PP4R2 and PP4c interacted with the PP4R3α and eNOS proteins. In summary, PA decreases PP4R2 protein expression through the Nox/ROS pathway to activate PP4, which contributes to ED by dephosphorylating eNOS at Ser633. The results of this study suggest that PP4 is a novel therapeutic target for ED and ED-associated vascular diseases.


Assuntos
Óxido Nítrico Sintase Tipo III , Fosfoproteínas Fosfatases , Doenças Vasculares , Humanos , Fosforilação , Óxido Nítrico Sintase Tipo III/metabolismo , Ácido Palmítico/farmacologia , Serina/metabolismo , Espécies Reativas de Oxigênio , Células Cultivadas , Proteína Fosfatase 2/metabolismo , Óxido Nítrico/metabolismo
2.
J Environ Manage ; 360: 121112, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38733847

RESUMO

Assessing net primary productivity (NPP) dynamics and the contribution of land-use change (LUC) to NPP can help guide scientific policy to better restore and control the ecological environment. Since 1999, the "Green for Grain" Program (GGP) has strongly affected the spatial and temporal pattern of NPP on the Loess Plateau (LP); however, the multifaceted impact of phased vegetation engineering measures on NPP dynamics remains unclear. In this study, the Carnegie-Ames-Stanford Approach (CASA) model was used to simulate NPP dynamics and quantify the relative contributions of LUC and climate change (CC) to NPP under two different scenarios. The results showed that the average NPP on the LP increased from 240.7 gC·m-2 to 422.5 gC·m-2 from 2001 to 2020, with 67.43% of the areas showing a significant increasing trend. LUC was the main contributor to NPP increases during the study period, and precipitation was the most important climatic factor affecting NPP dynamics. The cumulative amount of NPP change caused by LUC (ΔNPPLUC) showed a fluctuating growth trend (from 46.23 gC·m-2 to 127.25 gC·m-2), with a higher growth rate in period ΙΙ (2010-2020) than in period Ι (2001-2010), which may be related to the accumulation of vegetation biomass and the delayed effect of the GGP on NPP. The contribution rate of LUC to increased NPP in periods Ι and ΙΙ was 101.2% and 51.2%, respectively. Regarding the transformation mode, the transformation of grassland to forest had the greatest influence on ΔNPPLUC. Regarding land-use type, the increased efficiency of NPP was improved in cropland, grassland, and forest. This study provides a scientific basis for the scientific management and development of vegetation engineering measures and regional sustainable development.


Assuntos
Mudança Climática , Conservação dos Recursos Naturais , Ecossistema
3.
Ann Hematol ; 102(5): 1073-1086, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36943465

RESUMO

Acute myeloid leukemia (AML) is the most common hematopoietic malignancy with abnormal lipid metabolism. However, currently available information on the involvement of the alterations in lipid metabolism in AML development is limited. In this study, we demonstrate that FABP5 expression facilitates AML cell viability, protects AML cells from apoptosis, and maintains triglyceride production. Our bioinformatics analysis revealed that FABP5 expression was upregulated and correlated with unfavorable overall survival of AML patients. FABP5 expression may be used to distinguish normal and AML with high accuracy. FABP5-based risk score was an independent risk factor for AML patients. AML patients with highly expressed FABP5 predicted resistance to drugs. In vitro study showed that FABP5 expression was remarkably elevated in primary AML blasts and an AML cell line. Silencing FABP5 expression attenuated AML cell viability, reduced triglyceride production and lipid droplet accumulation, and induced apoptosis. We utilized AutoDock online tool to identify lycorine as an FABP5 inhibitor by binding FABP5 at amino acid residues Ile54, Thr56, Thr63, and Arg109. Lycorine treatment downregulated the expression levels of FABP5 and its target PPARγ, impaired AML cell viability, triggered apoptosis, and reduced triglyceride production in AML cells. These results demonstrate that FABP5 is critical for AML cell survival and highlight a novel metabolic vulnerability for AML.


Assuntos
Alcaloides de Amaryllidaceae , Leucemia Mieloide Aguda , Humanos , Linhagem Celular Tumoral , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Apoptose , Proliferação de Células , Proteínas de Ligação a Ácido Graxo/genética
4.
Cell Mol Biol (Noisy-le-grand) ; 69(2): 19-25, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-37224050

RESUMO

Ulcerative colitis (UC), which belongs to inflammatory bowel diseases (IBD), frequently induces liver inflammation and injury. Previous studies have proved that bone marrow-derived mesenchymal stem cells (BMSCs) can suppress inflammation and improve intestinal mucosal injury in colitis, however, the effects of BMSCs on colitis-induced liver injury and the underlying molecular mechanisms remain unclear. Here, we investigated the effects and mechanisms of BMSCs in acute ulcerative colitis BALB/c mice, which were induced by 4 % dextran sodium sulphate (DSS). In this study, BMSCs derived from BALB/c mice were administrated by single intravenous injection with a dose of 5*10^7 cells/kg. And then, the effects and underlying molecular mechanisms were investigated. Firstly, the degree of liver injury in colitis mice was evaluated by hepatic ALT, AST, ALP and TBIL levels, which were measured by specific determination kits, the levels of TNF-α, IL-6, IFNγ and LPS were examined by ELISA. Secondly, as the indicator of intestinal-liver barrier disorder, tight junction proteins were analyzed by western blot. Thirdly, the pathological changes in the colon and liver were detected by H&E staining. At last, homing of BMSCs to lesion tissues was investigated by Immunofluorescence. The results indicated that histopathological changes in model mice had been greatly alleviated, BMSCs infusion remarkably decreased the serum ALT, AST, ALP and TBIL levels, and meanwhile reduced pro-inflammatory cytokines in liver tissues. Furthermore, homing of BMSCs was observed in the colon and liver, and the disorder of the intestinal-liver barrier declined significantly. In conclusion, BMSCs alleviate liver injury induced by ulcerative colitis via repairing the intestinal-liver barrier and activating hepatocyte growth factor, it has potential application prospects in the treatment of liver injury induced by ulcerative colitis.


Assuntos
Colite Ulcerativa , Hepatite , Fator de Crescimento de Hepatócito , Transplante de Células-Tronco Mesenquimais , Animais , Camundongos , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/terapia , Fator de Crescimento de Hepatócito/metabolismo , Inflamação , Fígado , Camundongos Endogâmicos BALB C , Hepatite/complicações
5.
Scand J Immunol ; 95(6): e13158, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35285047

RESUMO

Acute myeloid leukaemia (AML) is very common haematopoietic malignancies with poor prognosis. Chemotherapy is still a mainstay therapy for AML patients. AML microenvironment plays critical roles in therapy response. However, the role of chemotherapy in AML microenvironment is poorly understood. In this study, we report that cytarabine (AraC)-triggered TNFα from AML cells expanded myeloid-derived suppressor cells (MDSCs) and enhanced MDSC functions and survival through activating IL-6/STAT3 and NFκB pathways. Blockade of TNFα in conditioned medium-derived AraC-treated AML cells (AraC_CM) impaired MDSC expansion and functions, reduced IL-6 secretion and the level of activated STAT3. Inhibiting IL6 or STAT3 abrogated AraC_CM-mediated MDSC suppressive function. Additionally, inhibiting TNFα also impaired AraC_CM-mediated NFκB activation. Blocking NFκB activation reduced MDSC viability induced by AraC_CM. Together, these results provided a role of AraC-induced TNFα in MDSC expansion and functions and suggest that targeting TNFα may benefit AML patients to current anticancer strategies by blocking MDSC-mediated immunosuppression.


Assuntos
Leucemia Mieloide Aguda , Células Supressoras Mieloides , Citarabina/metabolismo , Citarabina/farmacologia , Citarabina/uso terapêutico , Humanos , Interleucina-6/metabolismo , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Células Supressoras Mieloides/patologia , Microambiente Tumoral , Fator de Necrose Tumoral alfa/metabolismo
6.
Arch Virol ; 167(6): 1475-1479, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35449474

RESUMO

Aspergillus niger is an important filamentous phytopathogenic fungus with a broad host range. A novel double-stranded (ds) RNA mycovirus, named Aspergillus niger victorivirus 1 (AnV1), isolated from A. niger strain baiyun3.23-4, was sequenced and analyzed. The AnV1 genome is 5317 nucleotides long with a GC content of 56%. AnV1 contains two open reading frames (ORF1 and 2), overlapping at a tetranucleotide sequence (AUGA). ORF1 encodes a putative capsid protein (CP) of 778 amino acids (aa), while ORF2 potentially encodes a putative RNA-dependent RNA polymerase (RdRp) of 826 aa. Phylogenetic analysis indicated that AnV1 is a new member of the genus Victorivirus in the family Totiviridae. As far as we know, this is the first report of the complete genome sequence of a victorivirus infecting A. niger.


Assuntos
Micovírus , Vírus de RNA , Totiviridae , Aspergillus niger/genética , Micovírus/genética , Genoma Viral , Fases de Leitura Aberta , Filogenia , Vírus de RNA/genética , RNA de Cadeia Dupla , RNA Viral/genética , Proteínas Virais/química , Proteínas Virais/genética
7.
BMC Gastroenterol ; 22(1): 232, 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35546391

RESUMO

BACKGROUND: The detection rate of methylated Septin9 (mSEPT9) in colorectal cancer (CRC) is varied greatly across the studies. This study aimed to evaluate the diagnostic ability of mSEPT9 in CRC, and compare the diagnostic efficacy with fecal immunochemical test (FIT). METHODS: 326 subjects from four centers were prospectively recruited, including 179 CRC and 147 non-CRC subjects. The plasma was collected for mSEPT9 and CEA, AFP, CA125, CA153 and CA199 test, and fecal samples for FIT tests. Sensitivity, specificity and area under the curve (AUC) of receiver operating characteristic curve were calculated to evaluate the diagnostic value of each biomarker. RESULTS: The positive rate in mSEPT9 and FIT, and the level of CEA, CA125 and CA199 were significantly higher in CRC compared with non-CRC subjects. The mSEPT9 positive rate was not associated with TNM stage and tumor stage. The sensitivity, specificity and AUC of mSEPT9 in diagnostic CRC were 0.77, 0.88 and 0.82, respectively, while the value in FIT was 0.88, 0.80 and 0.83, respectively. mSEPT9 and FIT have higher AUC value than that of CEA, CA125 and CA199. Combination of both mSEPT9 and FIT positive increased sensitivity and AUC to 0.98 and 0.83, respectively, but the specificity was declined. mSEPT9 has a slightly low sensitivity in diagnosis of colon cancer (0.87) compared with rectal cancer (0.93). CONCLUSION: mSEPT9 demonstrated moderate diagnostic value in CRC detection, which was similar to the FIT but superior to the CEA, CA125 and CA199. Combination of mSEPT9 and FIT further improved diagnostic sensitivity in CRC. TRIAL REGISTRATION: ChiCTR2000038319.


Assuntos
Neoplasias Colorretais , Septinas , Biomarcadores Tumorais , Antígeno Carcinoembrionário , China , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/patologia , Detecção Precoce de Câncer , Humanos , Septinas/genética , Septinas/metabolismo
8.
Arch Virol ; 166(2): 659-664, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33404858

RESUMO

The bisegmented genome of a novel double-stranded (ds) RNA mycovirus, named "Aspergillus nidulans partitivirus 1" (AnPV1), isolated from the fungus Aspergillus nidulans strain HJ5-47, was sequenced and analyzed. AnPV1 contains two segments, AnPV1-1 and AnPV1-2. AnPV1-1 has 1837 bp with an open reading frame (ORF) that potentially encodes a putative RNA-dependent RNA polymerase (RdRp) of 572 amino acids (aa). AnPV1-2 has 1583 bp with an ORF encoding a putative capsid protein (CP) of 488 aa. Phylogenetic analyses indicated that AnPV1 and related viruses clustered in a group that could represent a new unclassified genus in the family Partitiviridae.


Assuntos
Aspergillus nidulans/virologia , Micovírus/genética , Genoma Viral/genética , Vírus de RNA/genética , Sequência de Aminoácidos , Sequência de Bases , Proteínas do Capsídeo/genética , Fases de Leitura Aberta/genética , Filogenia , RNA de Cadeia Dupla/genética , RNA Viral/genética , RNA Polimerase Dependente de RNA/genética , Análise de Sequência de DNA/métodos
9.
Mikrochim Acta ; 187(1): 93, 2020 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-31900676

RESUMO

A fluorometric assay for histidine (His) is described. It is based on the inhibitory effect of His on nanocubes consisting of cobalt-containing Prussian Blue analog (CoFe NCbs), which have a strong oxidation effect on thiamine (THI) in the presence of NaOH. THI is nonfluorescent but the oxidized form (thiochrome; ThC) has a strong blue fluorescence, with excitation/emission maxima at 370/445 nm. His inhibits the oxidation effect of the CoFe NCbs due to the strong interaction between its imidazole side chain and the amino groups of the CoFe NCbs. This method is fast and has good sensitivity and selectivity. The lower detection limit is 14.3 nM of His, the linear range extends from 0.05 to 2.5 µM, and the relative standard deviation is calculated to be 1.5%. The method was successfully employed to quantify His in spiked serum samples. Graphical abstractSchematic representation of cobalt-containing Prussian Blue nanocubes (CoFe NCbs)-thiamine (THI)-based fluorometric assay for Histine (His). His inhibits the generation of thiochrome (ThC; the oxidized form of THI). The detection limit is 14.3 nM with the linear range of 0.05-2.5 µM.


Assuntos
Cobalto/química , Ferrocianetos/química , Fluorometria/métodos , Histidina/análise , Tiamina/química , Fluorescência , Fluorometria/normas , Histidina/sangue , Histidina/farmacologia , Nanopartículas/química , Oxirredução , Tiamina/análogos & derivados , Tiamina/antagonistas & inibidores
10.
Exp Cell Res ; 362(1): 180-187, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-29196167

RESUMO

Oxidative stress-mediated activation of NLRP3 inflammasome in microglia is critical in the development of neurodegerative diseases such as Alzheimer's disease (AD), Parkinson disease (PD). However, the mechanism underlying oxidative stress activates NLRP3 inflammasome remains exclusive. Here we demonstrated cathepsin B (CTSB) as a regulator of the activation of NLRP3 inflammasome by H2O2·H2O2 induced IL-1ß secretion in NLRP3 inflammasome-dependent manner·H2O2 treatment increased CTSB activity, which in turn activated NLRP3 inflammasome, and subsequently processed pro-caspase-1 cleavage into caspase-1, resulting in IL-1 ß secretion. Genetic inhibition or pharmacological inhibition of CTSB blocked the cleavage of pro-caspase-1 into caspase-1 and subsequent IL-1 ß secretion induced by H2O2. Importantly, CTSB activity, IL-1ß levels and malondialdehyde (MDA) were remarkably elevated in plasma of AD patients compared to healthy controls, while glutathione was significantly lower than healthy controls. Correlation analyses showed that CTSB activity was positively correlated with IL-1ß and MDA levels, but negatively correlated with GSH levels in plasma of AD patients. Taken together, our results indicate that oxidative stress activates NLRP3 through upregulating CTSB activity. Our results identify an important biological function of CTSB in neuroinflammation, suggesting that CTSB is a potential target in AD therapy.


Assuntos
Catepsina B/farmacologia , Inflamassomos/efeitos dos fármacos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Animais , Caspase 1/metabolismo , Linhagem Celular , Feminino , Glutationa/metabolismo , Humanos , Peróxido de Hidrogênio/farmacologia , Inflamassomos/metabolismo , Interleucina-1beta/metabolismo , Masculino , Malondialdeído/metabolismo , Camundongos , Microglia/efeitos dos fármacos , Microglia/metabolismo , Pessoa de Meia-Idade
11.
Blood ; 127(13): 1687-700, 2016 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-26796361

RESUMO

Targeting oncogenic transcription factor signal transducer and activator of transcription 3 (STAT3) in acute myeloid leukemia (AML) can reduce blast survival and tumor immune evasion. Decoy oligodeoxynucleotides (dODNs), which comprise STAT3-specific DNA sequences are competitive inhibition of STAT3 transcriptional activity. To deliver STAT3dODN specifically to myeloid cells, we linked STAT3dODN to the Toll-like receptor 9 (TLR9) ligand, cytosine guanine dinucleotide (CpG). The CpG-STAT3dODN conjugates are quickly internalized by human and mouse TLR9(+)immune cells (dendritic cells, B cells) and the majority of patients' derived AML blasts, including leukemia stem/progenitor cells. Following uptake, CpG-STAT3dODNs are released from endosomes, and bind and sequester cytoplasmic STAT3, thereby inhibiting downstream gene expression in target cells. STAT3 inhibition in patients' AML cells limits their immunosuppressive potential by reduced arginase expression, thereby partly restoring T-cell proliferation. Partly chemically modified CpG-STAT3dODNs have >60 hours serum half-life which allows for IV administration to leukemia-bearing mice (50% effective dose ∼ 2.5 mg/kg). Repeated administration of CpG-STAT3dODN resulted in regression of human MV4-11 AML in mice. The antitumor efficacy of this strategy is further enhanced in immunocompetent mice by combining direct leukemia-specific cytotoxicity with immunogenic effects of STAT3 blocking/TLR9 triggering. CpG-STAT3dODN effectively reducedCbfb/MYH11/MplAML burden in various organs and eliminated leukemia stem/progenitor cells, mainly through CD8/CD4 T-cell-mediated immune responses. In contrast, small-molecule Janus kinase 2/STAT3 inhibitor failed to reproduce therapeutic effects of cell-selective CpG-STAT3dODN strategy. These results demonstrate therapeutic potential of CpG-STAT3dODN inhibitors with broad implications for treatment of AML and potentially other hematologic malignancies.


Assuntos
Ilhas de CpG , Genes cdc/efeitos dos fármacos , Leucemia Mieloide Aguda , Oligodesoxirribonucleotídeos/farmacologia , Fator de Transcrição STAT3/antagonistas & inibidores , Evasão Tumoral/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/imunologia , Estabilidade de Medicamentos , Genes cdc/imunologia , Terapia Genética/métodos , Humanos , Leucemia Mieloide Aguda/imunologia , Leucemia Mieloide Aguda/patologia , Leucemia Mieloide Aguda/terapia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Terapia de Alvo Molecular , Oligodesoxirribonucleotídeos/química , Oligodesoxirribonucleotídeos/uso terapêutico , Fator de Transcrição STAT3/química , Fator de Transcrição STAT3/genética , Soro/fisiologia , Transdução de Sinais/efeitos dos fármacos
12.
Biochem Biophys Res Commun ; 485(2): 432-439, 2017 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-28209511

RESUMO

Heparanase-1/syndecan-1 axis plays critical roles in tumorigenesis and development. The main mechanism includes heparanase-1 (HPA-1) degrades the heparan sulfate chain of syndecan-1 (SDC-1), and the following shedding of heparan sulfate from tumor cell releases and activates SDC-1 sequestered growth factors. However, the significance of Heparanase-1/syndecan-1 axis and its effects on the microenvironment of lymphatic metastasis in hepatocellular carcinogenesis (HCC) procession have not been reported. Herein, we found that HPA-1 could degrade the heparan sulfate on hepatocarcinoma cell surface. Importantly, HPA-1-induced shedding of heparan sulfate chain from SDC-1 facilitated the release of vascular endothelial growth factor C (VEGF-C) from SDC-1/VEGF-C complex into the medium of hepatocarcinoma cell. Further studies indicated that VEGF-C secretion from hepatocarcinoma cell promoted lymphatic endothelial cell growth through activating extracellular signal-regulated kinase (ERK) signaling. Taken together, this study reveals a novel existence of Heparanase-1/syndecan-1 axis in hepatocarcinoma cell and its roles in the cross-talking with the microenvironment of lymphatic metastasis.


Assuntos
Proliferação de Células , Células Endoteliais/metabolismo , Glucuronidase/metabolismo , Heparitina Sulfato/metabolismo , Sistema de Sinalização das MAP Quinases , Sindecana-1/metabolismo , Fator C de Crescimento do Endotélio Vascular/metabolismo , Animais , Western Blotting , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Glucuronidase/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Metástase Linfática , Vasos Linfáticos/citologia , Camundongos , Ligação Proteica , Interferência de RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sindecana-1/genética , Microambiente Tumoral
13.
Blood ; 123(1): 15-25, 2014 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-24169824

RESUMO

Signal transducer and activator of transcription 3 (STAT3) is an oncogene and immune checkpoint commonly activated in cancer cells and in tumor-associated immune cells. We previously developed an immunostimulatory strategy based on targeted Stat3 silencing in Toll-like receptor 9 (TLR9)-positive hematopoietic cells using CpG-small interfering RNA (siRNA) conjugates. Here, we assessed the therapeutic effect of systemic STAT3 blocking/TLR9 triggering in disseminated acute myeloid leukemia (AML). We used mouse Cbfb-MYH11/Mpl-induced leukemia model, which mimics human inv(16) AML. Our results demonstrate that intravenously delivered CpG-Stat3 siRNA, but not control oligonucleotides, can eradicate established AML and impair leukemia-initiating potential. These antitumor effects require host's effector T cells but not TLR9-positive antigen-presenting cells. Instead, CpG-Stat3 siRNA has direct immunogenic effect on AML cells in vivo upregulating major histocompatibility complex class-II, costimulatory and proinflammatory mediators, such as interleukin-12, while downregulating coinhibitory PD-L1 molecule. Systemic injections of CpG-Stat3 siRNA generate potent tumor antigen-specific immune responses, increase the ratio of tumor-infiltrating CD8(+) T cells to regulatory T cells in various organs, and result in CD8(+) T-cell-dependent regression of leukemia. Our findings underscore the potential of using targeted STAT3 inhibition/TLR9 triggering to break tumor tolerance and induce immunity against AML and potentially other TLR9-positive blood cancers.


Assuntos
Regulação Leucêmica da Expressão Gênica , Leucemia/imunologia , Leucemia/metabolismo , Fator de Transcrição STAT3/genética , Receptor Toll-Like 9/metabolismo , Animais , Linfócitos T CD8-Positivos/citologia , Linhagem Celular Tumoral , Ilhas de CpG , Inativação Gênica , Tolerância Imunológica , Interferon gama/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Camundongos Transgênicos , RNA Interferente Pequeno/metabolismo , Fator de Transcrição STAT3/metabolismo
14.
J Urol ; 193(4): 1114-21, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25286010

RESUMO

PURPOSE: Pazopanib has been assessed primarily in cytokine refractory or treatment naïve patients with metastatic renal cell carcinoma. Outcomes have been associated with a specific immunological profile. However, pazopanib activity in the third line setting and temporal changes in the immunological profile during therapy are poorly understood. MATERIALS AND METHODS: Study eligibility was limited to patients with 2 prior lines of therapy, including at least 1 vascular endothelial growth factor directed therapy, as well as ECOG performance status 0 to 2 and clear cell histology. Patients received pazopanib 800 mg daily. A Simon minmax 2-stage design was used with 80% power to determine an encouraging 23% overall response rate (10% type I error). Immunological profiles were assessed monthly on a Luminex® platform using the Human Cytokine 30-Plex Cytokine Immunoassay (Invitrogen™). RESULTS: A total of 28 patients with a median age of 63 years (range 45 to 86) were enrolled in study. Of the patients 12 (43%) had a confirmed complete (1) or partial (11) response. In the cohort median progression-free survival was 16.5 months (95% CI 14.7-not reached). The most common grade 3/4 toxicities were hypertension (46% of cases) and proteinuria (14%). At 6 and 12 months responders had lower levels of HGF, VEGF, IL-6 and 8, and soluble IL-2R (each p <0.05). Nonresponders also showed increased numbers of myeloid-derived suppressor cells at each interval. Phenotypic and functional studies confirmed that the myeloid-derived suppressor cells were granulocytic. CONCLUSIONS: Progression-free survival and the overall response rate associated with third line pazopanib were encouraging. Immunological profile differences between responders and nonresponders suggest that the mechanism of pazopanib resistance is at least partly related to the generation of systemic tumor immune tolerance.


Assuntos
Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/secundário , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/patologia , Pirimidinas/uso terapêutico , Receptores de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Sulfonamidas/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/sangue , Carcinoma de Células Renais/sangue , Feminino , Humanos , Indazóis , Neoplasias Renais/sangue , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Resultado do Tratamento
15.
Blood ; 121(8): 1304-15, 2013 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-23287859

RESUMO

STAT3 operates in both cancer cells and tumor-associated immune cells to promote cancer progression. As a transcription factor, it is a highly desirable but difficult target for pharmacologic inhibition. We have recently shown that the TLR9 agonists CpG oligonucleotides can be used for targeted siRNA delivery to mouse immune cells. In the present study, we demonstrate that a similar strategy allows for targeted gene silencing in both normal and malignant human TLR9(+) hematopoietic cells in vivo. We have developed new human cell-specific CpG(A)-STAT3 siRNA conjugates capable of inducing TLR9-dependent gene silencing and activation of primary immune cells such as myeloid dendritic cells, plasmacytoid dendritic cells, and B cells in vitro. TLR9 is also expressed by several human hematologic malignancies, including B-cell lymphoma, multiple myeloma, and acute myeloid leukemia. We further demonstrate that oncogenic proteins such as STAT3 or BCL-X(L) are effectively knocked down by specific CpG(A)-siRNAs in TLR9(+) hematologic tumor cells in vivo. Targeting survival signaling using CpG(A)-siRNAs inhibits the growth of several xenotransplanted multiple myeloma and acute myeloid leukemia tumors. CpG(A)-STAT3 siRNA is immunostimulatory and nontoxic for normal human leukocytes in vitro. The results of the present study show the potential of using tumoricidal/immunostimulatory CpG-siRNA oligonucleotides as a novel 2-pronged therapeutic strategy for hematologic malignancies.


Assuntos
Terapia Genética/métodos , Neoplasias Hematológicas/terapia , Células-Tronco Hematopoéticas/fisiologia , RNA Interferente Pequeno/farmacocinética , Receptor Toll-Like 9/genética , Animais , Linhagem Celular Tumoral , Técnicas de Transferência de Genes , Neoplasias Hematológicas/genética , Células-Tronco Hematopoéticas/patologia , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapia , Linfoma/genética , Linfoma/terapia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Mieloma Múltiplo/genética , Mieloma Múltiplo/terapia , Transplante de Neoplasias , Oligodesoxirribonucleotídeos/genética , RNA Interferente Pequeno/genética , Radioterapia , Fator de Transcrição STAT3/genética , Receptor Toll-Like 9/metabolismo , Transplante Heterólogo
16.
Arch Toxicol ; 89(11): 1981-91, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25417050

RESUMO

To reveal the molecular mechanism of deficit in learning and memory induced by chronic fluorosis, the expression of muscarinic acetylcholine receptors (mAChRs) and oxidative stress were investigated. Sixty Sprague-Dawley (SD) rats were divided randomly into two groups (30 cases in each), i.e., the control group (<0.5 ppm fluoride in drinking water) and the fluoride group (50 ppm fluoride) for 10 months of treatment. The pups born from SD mothers with or without chronic fluorosis were selected at postnatal days 1, 7, 14, 21 and 28 for experiments (10 for each age). Spatial learning and memory were evaluated by Morris water maze test. The expressions of M1 and M3 mAChRs at the protein and mRNA levels were determined by Western blotting and real-time PCR, respectively. In addition, the contents of (·)OH, H2O2, O2(·-) and malondialdehyde (MDA), and activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in brains were quantitated by biochemical methods. Our results showed that as compared to controls, the abilities of learning and memory were declined in the adult rats and the offspring rats of postnatal day 28 in the fluoride groups; the expressions of both M1 and M3 mAChRs were significantly reduced at protein and mRNA levels; and the levels of (·)OH, H2O2, O2(·-) and MDA were significantly increased, while the activities of SOD and GSH-Px decreased. Interestingly, the decreased protein levels of M1 and M3 mAChRs were significantly correlated with the deficits of learning and memory and high level of oxidative stress induced by chronic fluorosis. Our results suggest that the mechanism for the deficits in learning and memory of rats with chronic fluorosis may be associated with the decreased expressions of M1 and M3 in mAChRs, in which the changes in the receptors might be the result of the high level of oxidative stress occurring in the disease.


Assuntos
Fluorose Dentária/complicações , Transtornos da Memória/etiologia , Receptor Muscarínico M1/genética , Receptor Muscarínico M3/genética , Animais , Doença Crônica , Modelos Animais de Doenças , Feminino , Regulação da Expressão Gênica , Glutationa Peroxidase/metabolismo , Peróxido de Hidrogênio/metabolismo , Masculino , Malondialdeído/metabolismo , Aprendizagem em Labirinto , Estresse Oxidativo , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo , Fatores de Tempo
17.
J Biol Chem ; 288(43): 31280-8, 2013 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-24019511

RESUMO

Signal transducer and activator of transcription 3 (Stat3) is a key mediator in the development of many cancers. For 20 years, it has been assumed that Stat3 mediates its biological activities as a nuclear localized transcription factor activated by many cytokines. However, recent studies from this laboratory and others indicate that Stat3 has an independent function in the mitochondria (mitoStat3) where it controls the activity of the electron transport chain (ETC) and mediates Ras-induced transformation of mouse embryo fibroblasts. The actions of mitoStat3 in controlling respiration and Ras transformation are mediated by the phosphorylation state of serine 727. To address the role of mitoStat3 in the pathogenesis of cells that are transformed, we used 4T1 breast cancer cells, which form tumors that metastasize in immunocompetent mice. Substitution of Ser-727 for an alanine or aspartate in Stat3 that has a mitochondrial localization sequence, MLS-Stat3, has profound effects on tumor growth, complex I activity of the ETC, and accumulation of reactive oxygen species (ROS). Cells expressing MLS-Stat3(S727A) display slower tumor growth, decreased complex I activity of the ETC, and increased ROS accumulation under hypoxia compared with cells expressing MLS-Stat3. In contrast, cells expressing MLS-Stat3(S727D) show enhanced tumor growth and complex I activity and decreased production of ROS. These results highlight the importance of serine 727 of mitoStat3 in breast cancer and suggest a novel role for mitoStat3 in regulation of ROS concentrations through its action on the ETC.


Assuntos
Neoplasias Mamárias Animais/metabolismo , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Proteínas de Neoplasias/metabolismo , Fator de Transcrição STAT3/metabolismo , Substituição de Aminoácidos , Animais , Linhagem Celular Transformada , Linhagem Celular Tumoral , Complexo I de Transporte de Elétrons/genética , Complexo I de Transporte de Elétrons/metabolismo , Feminino , Neoplasias Mamárias Animais/genética , Neoplasias Mamárias Animais/patologia , Camundongos , Mitocôndrias/genética , Proteínas Mitocondriais/genética , Mutação de Sentido Incorreto , Proteínas de Neoplasias/genética , Fosforilação/genética , Espécies Reativas de Oxigênio/metabolismo , Fator de Transcrição STAT3/genética , Serina/genética , Serina/metabolismo
18.
Neurochem Int ; 176: 105737, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38599243

RESUMO

BACKGROUND: Evidence from previous studies indicates that neuroinflammation contributes to the onset of Alzheimer's Disease (AD). Moreover, cellular dysfunction is induced by impaired signaling of neurotransmitters. This study aimed to explore the correlation between cellular immune dysfunction and neurotransmitter changes through cranial Magnetic Resonance Spectroscopy (MRS) in AD patients. METHODS: Here, 32 AD, 40 Vascular Dementia (VD), and 35 Non-Dementia Elderly Control (NDE) cases were enrolled. Flow cytometry was performed to characterize lymphocyte subsets in plasma samples. The IL-1ß and Caspase-1 levels were detected by ELISA. The NLRP3 expression level was measured by Western Blot (WB). The equivalence of N-acetylaspartate (NAA), Creatine (Cr), Choline (Cho), and Inositol (MI) in bilateral hippocampi of patients was examined by MRS. The association of NAA/Cr or MI/Cr ratios with the proportion of T lymphocyte subsets or NK cell subsets was determined through single-factor correlation analysis. RESULTS: The proportion of T lymphocyte subsets was significantly lower in the AD group than in the NDE group (P < 0.01). On the other hand, the Caspase-1, NLRP3, and IL-1ß protein expression levels were significantly higher in the AD group than in the other groups. Further analysis showed that the NAA/Cr ratio was lower in the AD group than in the NDE group. Additionally, a significant positive correlation was found between the NAA/Cr ratio and the MMSE score (r = 0.81, P < 0.01). Moreover, a significant positive correlation was observed between the NAA/Cr and T lymphocyte ratios. The NAA/Cr ratio was significantly negatively correlated with the proportion of NK cells in the blood (r = ï¼0.83, P < 0.01). A significant negative correlation was also recorded between the MI/Cr and T cell ratios in blood samples. CONCLUSIONS: Impaired cellular immune dysfunction in AD patients was significantly correlated with abnormal MRS. Neuroimmune dysfunction may contribute to the pathogenesis of AD and alter the metabolism of neurotransmitters such as aspartic acid and MI in the brains of AD patients. TRIAL REGISTRATION: Not applicable.


Assuntos
Doença de Alzheimer , Espectroscopia de Ressonância Magnética , Humanos , Doença de Alzheimer/imunologia , Doença de Alzheimer/metabolismo , Masculino , Feminino , Idoso , Espectroscopia de Ressonância Magnética/métodos , Imunidade Celular , Idoso de 80 Anos ou mais , Pessoa de Meia-Idade , Colina/metabolismo
19.
ACS Appl Mater Interfaces ; 16(8): 10822-10831, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38381141

RESUMO

Hydrogel coatings exhibit versatile applications in biomedicine, flexible electronics, and environmental science. However, current coating methods encounter challenges in simultaneously achieving strong interfacial bonding, robust hydrogel coatings, and the ability to coat substrates with controlled thickness. This paper introduces a novel approach to grow a double-network (DN) tough hydrogel coating on various substrates. The process involves initial substrate modification using a silane coupling agent, followed by the deposition of an initiator layer on its surface. Subsequently, the substrate is immersed in a DN hydrogel precursor, where the coating grows under ultraviolet (UV) illumination. Precise control over the coating thickness is achieved by adjusting the UV illumination duration and the initiator quantity. The experimental measurement of adhesion reveals strong bonding between the DN hydrogel coating and diverse substrates, reaching up to 1012.9 J/m2 between the DN hydrogel coating and a glass substrate. The lubricity performance of the DN hydrogel coating is experimentally characterized, which is dependent on the coating thickness, applied pressure, and sliding velocity. The incorporation of 3D printing technology into the current coating method enables the creation of intricate hydrogel coating patterns on a flat substrate. Moreover, the hydrogel coating's versatility is demonstrated through its effective applications in oil-water separation and antifogging glasses, underscoring its wide-ranging potential. The robust DN hydrogel coating method presented here holds promise for advancing hydrogel applications across diverse fields.

20.
World J Clin Cases ; 12(6): 1063-1075, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38464932

RESUMO

BACKGROUND: Alzheimer's disease (AD) is a serious disease causing human dementia and social problems. The quality of life and prognosis of AD patients have attracted much attention. The role of chronic immune inflammation in the pathogenesis of AD is becoming more and more important. AIM: To study the relationship among cognitive dysfunction, abnormal cellular immune function, neuroimaging results and poor prognostic factors in patients. METHODS: A retrospective analysis of 62 hospitalized patients clinical diagnosed with AD who were admitted to our hospital from November 2015 to November 2020. Collect cognitive dysfunction performance characteristics, laboratory test data and neuroimaging data from medical records within 24 h of admission, including Mini Mental State Examination Scale score, drawing clock test, blood T lymphocyte subsets, and neutrophils and lymphocyte ratio (NLR), disturbance of consciousness, extrapyramidal symptoms, electroencephalogram (EEG) and head nucleus magnetic spectroscopy (MRS) and other data. Multivariate logistic regression analysis was used to determine independent prognostic factors. the modified Rankin scale (mRS) was used to determine whether the prognosis was good. The correlation between drug treatment and prognostic mRS score was tested by the rank sum test. RESULTS: Univariate analysis showed that abnormal cellular immune function, extrapyramidal symptoms, obvious disturbance of consciousness, abnormal EEG, increased NLR, abnormal MRS, and complicated pneumonia were related to the poor prognosis of AD patients. Multivariate logistic regression analysis showed that the decrease in the proportion of T lymphocytes in the blood after abnormal cellular immune function (odd ratio: 2.078, 95% confidence interval: 1.156-3.986, P < 0.05) was an independent risk factor for predicting the poor prognosis of AD. The number of days of donepezil treatment to improve cognitive function was negatively correlated with mRS score (r = 0.578, P < 0.05). CONCLUSION: The decrease in the proportion of T lymphocytes may have predictive value for the poor prognosis of AD. It is recommended that the proportion of T lymphocytes < 55% is used as the cut-off threshold for predicting the poor prognosis of AD. The early and continuous drug treatment is associated with a good prognosis.

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