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1.
Front Neurol ; 15: 1362648, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38450069

RESUMO

Rhabdomyolysis (RM) induced by electric blankets is exceedingly rare, with only three cases identified in our literature review. Both RM and Guillain-Barré syndrome (GBS) present with similar clinical manifestations of myalgia and muscle weakness, posing a potential challenge for accurate diagnosis in clinical settings. This report presents the case of a 22-year-old man who developed RM subsequent to the use of an electric blanket. Despite undergoing plasma exchange and renal replacement therapy, the patient continued to exhibit poor muscle strength in both lower limbs. Subsequent comprehensive evaluation revealed the presence of concurrent GBS. Following a 5-day course of intravenous gamma globulin treatment, the patient experienced rapid recovery of muscle strength and was discharged. Additionally, we reviewed seven cases from the literature of coexistent RM and GBS. This indicated that investigation of the timing of onset of muscle strength decline in RM patients could help to identify potential concurrent neurological or muscular disorders. In cases in which concurrent GBS and RM cannot be definitively ascertained during early hospitalization, prioritizing plasma exchange treatment may lead to improved patient outcomes.

2.
Proc Natl Acad Sci U S A ; 120(39): e2305078120, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37695879

RESUMO

Current un-sustainable plastic management is exacerbating plastic pollution, an urgent shift is thus needed to create a recycling society. Such recovering carbon (C) and hydrogen (H) from waste plastic has been considered as one practical route to achieve a circular economy. Here, we performed a simple pyrolysis-catalysis deconstruction of waste plastic via a monolithic multilayer stainless-steel mesh catalyst to produce multiwalled carbon nanotubes (MWCNTs) and H2, which are important carbon material and energy carrier to achieve sustainable development. Results revealed that the C and H recovery efficiencies were as high as 86% and 70%, respectively. The unique oxidation-reduction process and improvement of surface roughness led to efficient exposure of active sites, which increased MWCNTs by suppressing macromolecule hydrocarbons. The C recovery efficiency declined by only 5% after 10 cycles, proving the long-term employment of the catalyst. This catalyst can efficiently convert aromatics to MWCNTs by the vapor-solid-solid mechanism and demonstrate good universality in processing different kinds of waste plastics. The produced MWCNTs showed potential in applications of lithium-ion batteries and telecommunication. Owing to the economic profits and environmental benefits of the developed route, we highlighted its potential as a promising alternative to conventional incineration, simultaneously achieving the waste-to-resource strategy and circular economy.

3.
Arterioscler Thromb Vasc Biol ; 43(8): e303-e322, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37199156

RESUMO

BACKGROUND: Numerous genome-wide association studies revealed that SNPs (single nucleotide polymorphisms) at the PHACTR1 (phosphatase and actin regulator 1) locus strongly correlate with coronary artery disease. However, the biological function of PHACTR1 remains poorly understood. Here, we identified the proatherosclerotic effect of endothelial PHACTR1, contrary to macrophage PHACTR1. METHODS: We generated global (Phactr1-/-) and endothelial cell (EC)-specific (Phactr1ECKO) Phactr1 KO (knockout) mice and crossed these mice with apolipoprotein E-deficient (Apoe-/-) mice. Atherosclerosis was induced by feeding the high-fat/high-cholesterol diet for 12 weeks or partially ligating carotid arteries combined with a 2-week high-fat/high-cholesterol diet. PHACTR1 localization was identified by immunostaining of overexpressed PHACTR1 in human umbilical vein ECs exposed to different types of flow. The molecular function of endothelial PHACTR1 was explored by RNA sequencing using EC-enriched mRNA from global or EC-specific Phactr1 KO mice. Endothelial activation was evaluated in human umbilical vein ECs transfected with siRNA targeting PHACTR1 and in Phactr1ECKO mice after partial carotid ligation. RESULTS: Global or EC-specific Phactr1 deficiency significantly inhibited atherosclerosis in regions of disturbed flow. PHACTR1 was enriched in ECs and located in the nucleus of disturbed flow areas but shuttled to cytoplasm under laminar flow in vitro. RNA sequencing showed that endothelial Phactr1 depletion affected vascular function, and PPARγ (peroxisome proliferator-activated receptor gamma) was the top transcription factor regulating differentially expressed genes. PHACTR1 functioned as a PPARγ transcriptional corepressor by binding to PPARγ through the corepressor motifs. PPARγ activation protects against atherosclerosis by inhibiting endothelial activation. Consistently, PHACTR1 deficiency remarkably reduced endothelial activation induced by disturbed flow in vivo and in vitro. PPARγ antagonist GW9662 abolished the protective effects of Phactr1 KO on EC activation and atherosclerosis in vivo. CONCLUSIONS: Our results identified endothelial PHACTR1 as a novel PPARγ corepressor to promote atherosclerosis in disturbed flow regions. Endothelial PHACTR1 is a potential therapeutic target for atherosclerosis treatment.


Assuntos
Aterosclerose , PPAR gama , Animais , Humanos , Camundongos , Aterosclerose/metabolismo , Colesterol , Estudo de Associação Genômica Ampla , Camundongos Knockout , PPAR gama/genética
4.
Phys Chem Chem Phys ; 24(45): 27923-27929, 2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36367502

RESUMO

The HER requires a highly efficient, cost-effective, and stable catalyst to adapt to the large-scale hydrogen industry. Nickel has been confirmed to be useful to drive the water splitting reaction, but the intrinsic performance remains unsatisfactory. In this work, nickel (EG-Ni) with compressive strain was prepared through a one-step electrochemical deposition strategy. It shows an outstanding enhancement for the HER, and it achieves a current density of 10 mA cm-2 at a low overpotential of 85.9 mV. A long-term durability test proves that the EG-Ni can tolerate a large current density of 100 mA cm-2, and the overpotential remains steady without dramatically increasing. Such a low overpotential and superior stability are attributed to the optimized adsorption energy on the catalyst surface, as evidenced by the downshifted position of the d-band center.

5.
Org Lett ; 24(42): 7822-7827, 2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36250588

RESUMO

A nonracemic 3-silyl-3-borylhex-4-enoate reagent has been developed. Its asymmetric crotylboration of aldehydes provides Z-anti-homoallylic alcohols possessing a trisubstituted vinylsilane in high yields with excellent stereo- and enantioselectivity. Diverse decoration of vinylsilane and ester groups, as well as formation of functionalized THF rings, showcase the potential of the approach in the synthesis of polyketide natural products.


Assuntos
Aldeídos , Silanos , Estereoisomerismo , Indicadores e Reagentes
6.
Huan Jing Ke Xue ; 43(6): 3016-3026, 2022 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-35686771

RESUMO

As an important carrier of human activities, the spatial type of land use has an important impact on the surface water environment. Taking the Ruoergai wetland as an example, based on object-oriented remote sensing interpretation of land use types combined with water quality examination data, this study analyzed the impact and driving mechanism of land use types at different scales on the surface water environment at the small watershed and buffer scale. ① It was found that the water quality of the Ruoergai wetland could been classified as water grade V, and it was slightly eutrophic as a whole. The main pollutants were total nitrogen(TN) and phosphorus(TP), and the pollution originated from domestic sewage and grazing. ② The environmental quality of surface water was closely related to land use types. There was a negative correlation between chemical oxygen demand(COD) and the proportion of water area, a positive correlation between TN and the proportion of swamp area, and a negative correlation between total TP. ③ There was a significant correlation between spatial land use types at different scales and surface water environment. The land use type within a buffer of 1000 m had the highest interpretation degree for all factors, the land use type within a buffer of 200 m had the greatest interpretation degree for COD, the land use type within a buffer of 500 m zone had the greatest interpretation degree for TP and TN, and the land use type within a buffer of 800 m had the greatest explanation for Chl-a. The results of this study showed that the Ruoergai wetland wetland had a certain purification effect on pollutants and eutrophication. However, different land use types had different effects on different pollutants. The water body had a purification effect on Fe2+, COD, and Chl-a, and the swamp had a purification effect on TP but a cumulative effect on TN. Thus, the small-buffer zone(≤ 1000 m) land use type should be controlled, the water body and swamp areas should be controlled, the self-purification capacity of wetland waters should be improved, and the surface water environment of the Ruoergai wetland should be further protected and repaired.


Assuntos
Poluentes Ambientais , Qualidade da Água , Humanos , Nitrogênio/análise , Fósforo/análise , Áreas Alagadas
7.
Br J Pharmacol ; 179(20): 4809-4828, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35737588

RESUMO

BACKGROUND AND PURPOSE: Notch1 activation mediated by γ-secretase is critical for angiogenesis. GeneCards database predicted that Caspase-4 (CASP4, with murine ortholog CASP11) interacts with presenilin-1, the catalytic core of γ-secretase. Therefore, we investigated the role of CASP4/11 in angiogenesis. EXPERIMENTAL APPROACH: In vivo, we studied the role of Casp11 in several angiogenesis mouse models using Casp11 wild-type and knockout mice. In vitro, we detected the effects of CASP4 on endothelial functions and Notch signalling by depleting or overexpressing CASP4 in human umbilical vein endothelial cells (HUVECs). The functional domain responsible for the binding of CASP4 and presenilin-1 was detected by mutagenesis and co-immunoprecipitation. KEY RESULTS: Casp11 deficiency impaired adult angiogenesis in ischaemic hindlimbs, melanoma xenografts and Matrigel plugs, but not the developmental angiogenesis of retina. Bone marrow transplantation revealed that the pro-angiogenic effect depended on CASP11 derived from non-haematopoietic cells. CASP4 expression was induced by inflammatory factors and CASP4 knockdown decreased cell viability, proliferation, migration and tube formation in HUVECs. Mechanistically, CASP4/11 deficiency increased Notch1 activation in vivo and in vitro, while CASP4 overexpression repressed Notch1 signalling in HUVECs. Moreover, CASP4 knockdown increased γ-secretase activity. The γ-Secretase inhibitor DAPT restored the effects of CASP4 siRNA on Notch1 activation and angiogenesis in HUVECs. Notably, the catalytic activity of CASP4/11 was dispensable. CASP4 directly interacted with presenilin-1 through the caspase recruitment domain (CARD). CONCLUSIONS AND IMPLICATIONS: These findings reveal a critical role of CASP4/11 in adult angiogenesis and make this molecule a promising therapeutic target for angiogenesis-related diseases in the future.


Assuntos
Secretases da Proteína Precursora do Amiloide , Caspases , Neovascularização Patológica , Receptor Notch1 , Animais , Caspases/metabolismo , Caspases Iniciadoras , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Camundongos , Camundongos Knockout , Neovascularização Patológica/metabolismo , Presenilina-1/genética , Presenilina-1/metabolismo , RNA Interferente Pequeno/genética , Receptor Notch1/genética , Receptor Notch1/metabolismo , Receptores Notch/genética , Receptores Notch/metabolismo
8.
Cancer Lett ; 540: 215720, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35533952

RESUMO

Historically, immunoglobulin (Ig) has been known as an antibody and is expressed only in B lineage cells; importantly, Ig light chains are conjugated to heavy chains to form intact Igs. However, in this study, we found a free Igκ light chain with a unique Vκ4-1/Jκ3 rearrangement (Vκ4-1/Jκ3-FLC) that was widely expressed in different non-B lineages and was overexpressed in cancer cells. Further study indicated that Vκ4-1/Jκ3-FLC was hydrophobic, formed obvious insoluble deposits in the extracellular matrix (ECM) and existed in free form. Functional analyses demonstrated that Vκ4-1/Jκ3-FLC promoted the proliferation, migration and metastasis of colon cancer cells in vitro and in vivo. Mechanistically, Vκ4-1/Jκ3-FLC bound to integrin ß1 and activated the FAK and Src pathways. More importantly, specific antibodies against the variable region of Vκ4-1/Jκ3-FLC significantly inhibited the growth of colon cancer tumors. Our findings suggested that Vκ4-1/Jκ3-FLC is a novel ECM protein and integrin ß1 ligand and that it is involved in cancer progression and is a potential therapeutic target in cancer, particularly colon cancer.


Assuntos
Neoplasias do Colo , Integrina beta1 , Neoplasias do Colo/genética , Quinase 1 de Adesão Focal/genética , Quinase 1 de Adesão Focal/metabolismo , Humanos , Cadeias kappa de Imunoglobulina , Integrina beta1/genética , Integrina beta1/metabolismo
9.
Hypertension ; 79(1): 79-92, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34739767

RESUMO

Clinical trials of Dll4 (Delta-like 4) neutralizing antibodies (Dll4nAbs) in cancer patients are ongoing. Surprisingly, pulmonary hypertension (PH) occurs in 14% to 18% of patients treated with Dll4nAbs, but the mechanisms have not been studied. Here, PH progression was measured in mice treated with Dll4nAbs. We detected Notch signaling in lung tissues and analyzed pulmonary vascular permeability and inflammation. Notch target gene array was performed on adult human pulmonary microvascular endothelial cells (ECs) after inhibiting Notch cleavage. Similar mechanisms were studied in PH mouse models and pulmonary arterial hypertension patients. The rescue effects of constitutively activated Notch1 in vivo were also measured. We observed that Dll4nAbs induced PH in mice as indicated by significantly increased right ventricular systolic pressure, as well as pulmonary vascular and right ventricular remodeling. Mechanistically, Dll4nAbs inhibited Notch1 cleavage and subsequently impaired lung endothelial barrier function and increased immune cell infiltration in vessel walls. In vitro, Notch targeted genes' expression related to cell growth and inflammation was decreased in human pulmonary microvascular ECs after the Notch1 inactivation. In lungs of PH mouse models and pulmonary arterial hypertension patients, Notch1 cleavage was inhibited. Consistently, EC cell-cell junction was leaky, and immune cell infiltration increased in PH mouse models. Overexpression activated Notch1-attenuated progression of PH in mice. In conclusion, Dll4nAbs led to PH development in mice by impaired EC barrier function and increased immune cell infiltration through inhibition of Notch1 cleavage in lung ECs. Reduced Notch1 cleavage in lung ECs could be an underlying mechanism of PH pathogenesis.


Assuntos
Hipertensão Pulmonar/metabolismo , Pulmão/metabolismo , Receptor Notch1/metabolismo , Animais , Anticorpos Neutralizantes/farmacologia , Células Endoteliais/metabolismo , Hipertensão Pulmonar/genética , Masculino , Camundongos , Artéria Pulmonar/metabolismo , Receptor Notch1/genética , Transdução de Sinais/genética
10.
Br J Pharmacol ; 179(8): 1716-1731, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34796471

RESUMO

BACKGROUND AND PURPOSE: The Dll4-Notch1 signalling pathway plays an important role in sprouting angiogenesis, vascular remodelling and arterial or venous specificity. Genetic or pharmacological inhibition of Dll4-Notch1 signalling leads to excessive sprouting angiogenesis. However, transcriptional inhibitors of Dll4-Notch1 signalling have not been described. EXPERIMENTAL APPROACH: We designed a new peptide targeting Notch signalling, referred to as TAT-ANK, and assessed its effects on angiogenesis. In vitro, tube formation and fibrin gel bead assay were carried out, using human umbilical vein endothelial cells (HUVECs). In vivo, Matrigel plug angiogenesis assay, a developmental retinal model and tumour models in mice were used. The mechanisms underlying TAT-ANK activity were investigated by immunochemistry, western blotting, immunoprecipitation, RT-qPCR and luciferase reporter assays. KEY RESULTS: The amino acid residues 179-191 in the G-protein-coupled receptor-kinase-interacting protein-1 (GIT1-ankyrin domain) are crucial for GIT1 binding to the Notch transcription repressor, RBP-J. We designed the peptide TAT-ANK, based on residues 179-191 in GIT1. TAT-ANK significantly inhibited Dll4 expression and Notch 1 activation in HUVECs by competing with activated Notch1 to bind to RBP-J. The analyses of biological functions showed that TAT-ANK promoted angiogenesis in vitro and in vivo by inhibiting Dll4-Notch1 signalling. CONCLUSIONS AND IMPLICATIONS: We synthesized and investigated the biological actions of TAT-ANK peptide, a new inhibitor of Notch signalling. This peptide will be of significant interest to research on Dll4-Notch1 signalling and to clinicians carrying out clinical trials using Notch signalling inhibitors. Furthermore, our findings will have important conceptual and therapeutic implications for angiogenesis-related diseases.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Proteínas de Ligação ao Cálcio , Neovascularização Fisiológica , Peptídeos , Receptor Notch1 , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Proteínas de Ligação ao Cálcio/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Camundongos , Neovascularização Patológica/tratamento farmacológico , Peptídeos/farmacologia , Receptor Notch1/antagonistas & inibidores , Receptor Notch1/metabolismo , Receptores Notch/genética , Receptores Notch/metabolismo , Transdução de Sinais
11.
Hypertens Res ; 44(7): 770-780, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33654247

RESUMO

Adventitia-induced vascular remodeling plays an important role in vascular aging. However, the mechanism remains unclear. In this study, we found that sirtuin 6 (SIRT6) expression was downregulated in the aortae of aged rats compared with those of young rats. Adventitial fibroblasts (AFs) were isolated and cultured from rat aortae to clarify the relationship between SIRT6 expression and vascular aging. Lentivirus-mediated SIRT6 knockdown promoted the aging phenotype in AFs, affecting proliferation, collagen secretion, migration, and α-smooth muscle actin expression. Moreover, angiotensin II (Ang II) decreased SIRT6 expression, activated the NF-κB pathway, and led to vascular aging. The NF-κB pathway inhibitor BAY 11-7082 reduced Ang II-induced nuclear translocation of the NF-κB p65 subunit and other effects of Ang II, such as AF proliferation, collagen secretion, and migration. Mechanistically, SIRT6 suppression increased acetyl-NF-κB p65 (Lys310) expression and NF-κB transcriptional activity in SIRT6-knockdown AFs. SIRT6 could directly bind to the p65 subunit and attenuate Ang II-induced NF-κB activation and vascular aging. In summary, this study was the first to correlate SIRT6 expression and adventitia-induced vascular senescence. SIRT6 maybe a biomarker of vascular aging, and activating SIRT6 maybe a therapeutic strategy for delaying vascular aging.


Assuntos
Envelhecimento , Fenômenos Fisiológicos Cardiovasculares , Sirtuínas , Envelhecimento/fisiologia , Angiotensina II/metabolismo , Animais , Aorta/fisiologia , NF-kappa B/metabolismo , Ratos , Sirtuínas/metabolismo
12.
Gene ; 772: 145378, 2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33359127

RESUMO

Immunoglobulins (Ig) are important immune molecules that possess highly diverse variable region sequences enabling antigen recognition. According to classical immune theory, B lymphocytes have been considered the only source of Ig production (B-Igs). However, accumulating evidence have suggested that Igs are also produced by many non-B cells (non-B Igs), including epithelial cells, neurons, germ cells, as well as myeloid cells of hemopoietic system. Besides acting as bona fide antibodies, Non-B Igs have alternative cellular functions, such as promotion of cell survival, adhesion and migration. More importantly, Unlike the unlimited sequence diversity of B-Igs, the non-B Igs exhibit conserved V(D)J patterns across the same lineages. To support the analysis and comparison of variable region sequences from Igs, produced by B and non-B cells, we established a database (NBIGV) constituted by a non-B Ig variable region repertoire, which includes 727,989 VHDJH and VκJκ recombination sequences of non-B Igs sequenced from mouse samples. Upon database search, users can view, browse and investigate the variable region sequences of non-B Igs according to respective mice strains and tissues as well as Ig classes. Moreover, users can easily download selected sequences and/or compare sequences of interest with known non-B Ig sequences present in the database using NCBI-BLAST algorithms. Additionally, our database integrates a submission page and supplementary sample information. The NBIGV database may serve as a valuable resource for sequence analyses of Non-B Igs. NBIGV database is freely available at http://nbigv.org.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala/métodos , Região Variável de Imunoglobulina/genética , Região Variável de Imunoglobulina/metabolismo , Algoritmos , Animais , Adesão Celular , Movimento Celular , Sobrevivência Celular , Bases de Dados Genéticas , Humanos , Camundongos , Análise de Sequência de DNA , Recombinação V(D)J
13.
Comput Math Methods Med ; 2020: 2018214, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32617116

RESUMO

BACKGROUND: Moyamoya disease (MMD) is a rare cerebrovascular disease characterized by chronic progressive stenosis or occlusion of the bilateral internal carotid artery (ICA), the anterior cerebral artery (ACA), and the middle cerebral artery (MCA). MMD is secondary to the formation of an abnormal vascular network at the base of the skull. However, the etiology and pathogenesis of MMD remain poorly understood. METHODS: A competing endogenous RNA (ceRNA) network was constructed by analyzing sample-matched messenger RNA (mRNA), long non-coding RNA (lncRNA), and microRNA (miRNA) expression profiles from MMD patients and control samples. Then, a protein-protein interaction (PPI) network was constructed to identify crucial genes associated with MMD. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes pathway (KEGG) enrichment analyses were employed with the DAVID database to investigate the underlying functions of differentially expressed mRNAs (DEmRNAs) involved in the ceRNA network. CMap was used to identify potential small drug molecules. RESULTS: A total of 94 miRNAs, 3649 lncRNAs, and 2294 mRNAs were differentially expressed between MMD patients and control samples. A synergistic ceRNA lncRNA-miRNA-mRNA regulatory network was constructed. Core regulatory miRNAs (miR-107 and miR-423-5p) and key mRNAs (STAT5B, FOSL2, CEBPB, and CXCL16) involved in the ceRNA network were identified. GO and KEGG analyses indicated that the DEmRNAs were involved in the regulation of the immune system and inflammation in MMD. Finally, two potential small molecule drugs, CAY-10415 and indirubin, were identified by CMap as candidate drugs for treating MMD. CONCLUSIONS: The present study used bioinformatics analysis of candidate RNAs to identify a series of clearly altered miRNAs, lncRNAs, and mRNAs involved in MMD. Furthermore, a ceRNA lncRNA-miRNA-mRNA regulatory network was constructed, which provides insights into the novel molecular pathogenesis of MMD, thus giving promising clues for clinical therapy.


Assuntos
Doença de Moyamoya/genética , RNA Longo não Codificante/genética , Estudos de Casos e Controles , Biologia Computacional , Bases de Dados de Ácidos Nucleicos , Bases de Dados de Produtos Farmacêuticos , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Ontologia Genética , Redes Reguladoras de Genes , Humanos , Indóis/farmacologia , MicroRNAs/genética , Anotação de Sequência Molecular , Doença de Moyamoya/tratamento farmacológico , Doença de Moyamoya/etiologia , Mapas de Interação de Proteínas/genética , RNA Mensageiro/genética , Tiazolidinedionas/farmacologia
14.
Cancer Genet ; 237: 1-9, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31447061

RESUMO

BACKGROUND: In recent years, many studies have confirmed that STIP1 (phosphorylation-induced protein 1) is involved in the development and progression of various tumors. However, its potential role in glioma progression and the underlying mechanisms of glioma development remain unclear. METHODS: We analyzed the expression of STIP1 in 35 human glioma tissue specimens of different grades, using 6 normal brain tissues for comparison. We transfected U87 and U251 cell lines with small interfering RNA (siRNA) to downregulate STIP1, and set up a negative control group and a blank group for comparison. The MTT assay was used to detect cell proliferation, and cell cycle progression and apoptosis were analyzed through flow cytometry. Transwell experiments were employed to detect the invasion and migration of STIP1-depleted and control U87 and U251 cells and western blotting was used to detect the expression of TRAP1/Akt pathway proteins. In addition, immunohistochemical analysis was used to reveal differences in expression and localization between transplanted tumor specimens of each group. RESULTS: We observed a high expression of STIP1 in glioblastoma, MTT assay revealed a decreased cell proliferation rate in the STIP1-downregulated cells. Cell cycle analysis revealed an increased proportion of cells in G1 phase, as well as an increase in apoptosis, upon STIP1 downregulation. Western blotting showed that TRAP1, pAkt, and MMP2 expression was decreased upon STIP1 downregulation. In addition, TRAP1, ki-67, and MMP2 displayed a decreased expression in vivo. CONCLUSIONS: STIP1 is highly expressed in glioblastoma compared to normal brain tissues. Downregulation of STIP1 in glioma cells reduces cell proliferation rate and invasion and increases cell apoptosis.


Assuntos
Apoptose/fisiologia , Neoplasias Encefálicas/metabolismo , Regulação para Baixo , Glioblastoma/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , Proteínas de Choque Térmico/fisiologia , Invasividade Neoplásica , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/fisiologia , Encéfalo/metabolismo , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Glioblastoma/patologia , Proteínas de Choque Térmico/genética , Humanos , Metaloproteinase 2 da Matriz/metabolismo , RNA Interferente Pequeno/genética
15.
Biochem Biophys Res Commun ; 507(1-4): 400-406, 2018 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-30448061

RESUMO

It is well recognized that decreased vascular endothelial growth factor A (VEGF-A) mRNA plays an important role in retinal vessel regression induced by hyperoxia. However, this concept has been challenged by increasing new evidence. Furthermore, VEGF-A strongly enhances Dll4 expression and inhibition of Dll4-Notch signaling leads to excessive sprouting angiogenesis. Recently, it is shown that inactivation of Dll4-Notch1 signaling reduce hyperoxia induced vessel regression. It is unknown whether sprouting angiogenesis contributes to the protective effect or not and further investigations are needed. Moreover, the expression of Dll4 or Notch1 activation in the regressing plexus remains elucidated. To determine the role of VEGF-A and Dll4-Notch1 signaling in hyperoxia induced vascular regression in the retina, we used mice at postnatal day 5 (P5) - P7. Hyperoxia induced massive vascular regression in the central plexus but not in the angiogenic plexus and had no effect on sprouting angiogenesis. Immunostaining showed that VEGF-A was significantly repressed in the angiogenic front region after hyperoxia exposure but not detectable in the central area of both normoxia and hyperoxia treated retinas. In contrast, Notch ligand Delta-like 4 (Dll4) and Notch1 intracellular domain (N1-ICD) expression were inhibited in the regressing capillaries of central retina but comparable in the angiogenic plexus after high oxygen treatment. Moreover, administration of Dll4 neutralizing antibody or γ-Secretase inhibitor DAPT significantly aggravated vessel regression induced by short-time hyperoxia administration. Our data show that repressed Dll4-Notch1 signaling pathway but not downregulation of VEGF-A expression are responsible for hyperoxia induced pervasive vessel regression.


Assuntos
Hiperóxia/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Membrana/metabolismo , Receptor Notch1/metabolismo , Retina/metabolismo , Retina/patologia , Transdução de Sinais , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Animais , Animais Recém-Nascidos , Proteínas de Ligação ao Cálcio , Camundongos , Neovascularização Fisiológica
17.
J Am Heart Assoc ; 6(7)2017 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-28698260

RESUMO

BACKGROUND: Vascular smooth muscle cell proliferation, migration, and dedifferentiation are critical for vascular diseases. Recently, it was demonstrated that Notch receptors have opposing effects on intima formation after vessel injury. Therefore, it is important to investigate the specific regulatory pathways that activate the different Notch receptors. METHODS AND RESULTS: There was a time- and dose-dependent activation of Notch1 by angiotensin II and platelet-derived growth factor in vascular smooth muscle cells. When phospholipase Cγ1 (PLCγ1) expression was reduced by small interfering RNA, Notch1 activation and Hey2 expression (Notch target gene) induced by angiotensin II or platelet-derived growth factor were remarkably inhibited, while Notch2 degradation was not affected. Mechanistically, we observed an association of PLCγ1 and Akt, which increased after angiotensin II or platelet-derived growth factor stimulation. PLCγ1 knockdown significantly inhibited Akt activation. Importantly, PLCγ1 phospholipase site mutation (no phospholipase activity) did not affect Akt activation. Furthermore, PLCγ1 depletion inhibited platelet-derived growth factor-induced vascular smooth muscle cell proliferation, migration, and dedifferentiation, while it increased apoptosis. In vivo, PLCγ1 and control small interfering RNA were delivered periadventitially in pluronic gel and complete carotid artery ligation was performed. Morphometric analysis 21 days after ligation demonstrated that PLCγ1 small interfering RNA robustly attenuated intima area and intima/media ratio compared with the control group. CONCLUSIONS: PLCγ1-Akt-mediated Notch1 signaling is crucial for intima formation. This effect is attributable to PLCγ1-Akt interaction but not PLCγ1 phospholipase activity. Specific inhibition of the PLCγ1 and Akt interaction will be a promising therapeutic strategy for preventing vascular remodeling.


Assuntos
Lesões das Artérias Carótidas/enzimologia , Músculo Liso Vascular/enzimologia , Miócitos de Músculo Liso/enzimologia , Neointima , Fosfolipase C gama/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor Notch1/metabolismo , Transdução de Sinais , Angiotensina II/farmacologia , Animais , Apoptose , Lesões das Artérias Carótidas/genética , Lesões das Artérias Carótidas/patologia , Desdiferenciação Celular , Movimento Celular , Proliferação de Células , Células Cultivadas , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Masculino , Camundongos Endogâmicos C57BL , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/patologia , Fosfolipase C gama/genética , Fosforilação , Fator de Crescimento Derivado de Plaquetas/farmacologia , Interferência de RNA , Ratos , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Transfecção , Remodelação Vascular
18.
Sci Rep ; 7(1): 5165, 2017 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-28701727

RESUMO

Numerous studies have demonstrated that free Ig light chain (FLC), a novel inflammation mediator, participates in many inflammatory diseases by activating mast cells and extending the survival of neutrophils. However, it remains unclear whether FLC is involved in colitis and colitis-associated colon carcinogenesis (CAC). In this study, we found a significant increase in FLC in murine models of DSS (Dextran Sulfate Sodium Salt)-induced colitis and CAC compared to controls. Peptide F991, a functional blocker of FLC, significantly attenuated colitis progression, which included abrogating the development of diarrhea and tumor burden, elevating survival rate, greatly reducing the infiltration of inflammatory cells (such as ROS+ active neutrophils), especially reducing tumorigenesis in CAC. Furthermore, we demonstrated that F991 inhibited the activation of the inflammasome by reducing the expression of cleaved caspase-1 and the maturation of IL-1ß and IL-18. Altogether, our findings demonstrate that FLC can promote the pathogenesis of colitis and CAC and may be used as novel biomarker for the diagnosis of inflammatory bowel disease. Additionally, F991 may become a potential therapeutic option for colitis or colorectal cancer.


Assuntos
Transformação Celular Neoplásica/metabolismo , Colite/etiologia , Colite/metabolismo , Neoplasias do Colo/etiologia , Neoplasias do Colo/metabolismo , Cadeias Leves de Imunoglobulina/metabolismo , Inflamassomos/metabolismo , Animais , Colite/complicações , Colite/patologia , Neoplasias do Colo/patologia , Sulfato de Dextrana/efeitos adversos , Modelos Animais de Doenças , Mediadores da Inflamação/metabolismo , Camundongos
19.
Elife ; 62017 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-28440748

RESUMO

SCP1 as a nuclear transcriptional regulator acts globally to silence neuronal genes and to affect the dephosphorylation of RNA Pol ll. However, we report the first finding and description of SCP1 as a plasma membrane-localized protein in various cancer cells using EGFP- or other epitope-fused SCP1. Membrane-located SCP1 dephosphorylates AKT at serine 473, leading to the abolishment of serine 473 phosphorylation that results in suppressed angiogenesis and a decreased risk of tumorigenesis. Consistently, we observed increased AKT phosphorylation and angiogenesis followed by enhanced tumorigenesis in Ctdsp1 (which encodes SCP1) gene - knockout mice. Importantly, we discovered that the membrane localization of SCP1 is crucial for impeding angiogenesis and tumor growth, and this localization depends on palmitoylation of a conserved cysteine motif within its NH2 terminus. Thus, our study discovers a novel mechanism underlying SCP1 shuttling between the plasma membrane and nucleus, which constitutes a unique pathway in transducing AKT signaling that is closely linked to angiogenesis and tumorigenesis.


Assuntos
Proteínas de Membrana/metabolismo , Neovascularização Fisiológica , Fosfoproteínas Fosfatases/metabolismo , Processamento de Proteína Pós-Traducional , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Membrana Celular/química , Lipoilação , Proteínas de Membrana/genética , Camundongos Knockout , Fosfoproteínas Fosfatases/genética , Fosforilação
20.
Cell Rep ; 17(10): 2532-2541, 2016 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-27926858

RESUMO

The spatiotemporal localization and expression of Dll4 are critical for sprouting angiogenesis. However, the related mechanisms are poorly understood. Here, we show that G-protein-coupled receptor-kinase interacting protein-1 (GIT1) is a robust endogenous inhibitor of Dll4-Notch1 signaling that specifically controls stalk cell fate. GIT1 is highly expressed in stalk cells but not in tip cells. GIT1 deficiency remarkably enhances Dll4 expression and Notch1 signaling, resulting in impaired retinal sprouting angiogenesis, which can be rescued by treatment with the Notch inhibitor or Dll4 neutralizing antibody. Notch1 regulates Dll4 expression by binding to recombining binding protein suppressor of hairless (RBP-J, a transcriptional regulator of Notch) via a highly conserved ankyrin (ANK) repeat domain. We show that GIT1, which also contains an ANK domain, inhibits the Notch1-Dll4 signaling pathway by competing with Notch1 ANK domain for binding to RBP-J in stalk cells.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas de Ciclo Celular/genética , Proteína de Ligação a Sequências Sinal de Recombinação J de Imunoglobina/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas de Membrana/genética , Neovascularização Fisiológica/genética , Receptor Notch1/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Ciclo Celular/metabolismo , Diferenciação Celular/genética , Proliferação de Células/genética , Células Endoteliais/metabolismo , Regulação da Expressão Gênica , Células Endoteliais da Veia Umbilical Humana , Humanos , Proteína de Ligação a Sequências Sinal de Recombinação J de Imunoglobina/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Membrana/metabolismo , Ligação Proteica , Receptor Notch1/metabolismo , Transdução de Sinais
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