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1.
Nano Lett ; 23(8): 3128-3136, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-36951295

RESUMO

In this study, a range of carbon nanotube yarn (CNTY) architectures was examined and controlled by chemical modification to gain a deeper understanding of CNTY load-bearing systems and produce lightweight and superstrong CNTYs. The architecture of CNTY, which has polymer layers surrounding a compact bundle without hampering the original state of the CNTs in the bundle, is a favorable design for further chemical cross-linking and for enhancing the load-transfer efficiency, as confirmed by in situ Raman spectroscopy under a stress load. The resulting CNTY exhibited excellent mechanical performance that exceeded the specific strength of the benchmark, high-performance fibers. This exceptional strength of the CNTY makes it a promising candidate for the cable of a space elevator traveling from the Earth to the International Space Station given its strength of 4.35 GPa/(g cm-3), which can withstand the self-weight of a 440 km cable.

2.
Int J Mol Sci ; 25(5)2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38473760

RESUMO

Bone differentiation is crucial for skeletal development and maintenance. Its dysfunction can cause various pathological conditions such as rickets, osteoporosis, osteogenesis imperfecta, or Paget's disease. Although traditional two-dimensional cell culture systems have contributed significantly to our understanding of bone biology, they fail to replicate the intricate biotic environment of bone tissue. Three-dimensional (3D) spheroid cell cultures have gained widespread popularity for addressing bone defects. This review highlights the advantages of employing 3D culture systems to investigate bone differentiation. It highlights their capacity to mimic the complex in vivo environment and crucial cellular interactions pivotal to bone homeostasis. The exploration of 3D culture models in bone research offers enhanced physiological relevance, improved predictive capabilities, and reduced reliance on animal models, which have contributed to the advancement of safer and more effective strategies for drug development. Studies have highlighted the transformative potential of 3D culture systems for expanding our understanding of bone biology and developing targeted therapeutic interventions for bone-related disorders. This review explores how 3D culture systems have demonstrated promise in unraveling the intricate mechanisms governing bone homeostasis and responses to pharmacological agents.


Assuntos
Técnicas de Cultura de Células , Osteogênese , Animais , Células Cultivadas , Técnicas de Cultura de Células/métodos , Diferenciação Celular/fisiologia , Osso e Ossos
3.
Stem Cells ; 40(4): 385-396, 2022 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-35262736

RESUMO

Lin28A is an RNA-binding protein that controls mammalian development and maintenance of the pluripotency of embryonic stem cells (ESCs) via regulating the processing of the microRNA let-7. Lin28A is highly expressed in ESCs, and ectopic expression of this protein facilitates reprogramming of somatic cells to induced pluripotent stem cells. However, the mechanisms underlying the post-translational regulation of Lin28A protein stability in ESCs remain unclear. In the present study, we identified Kap1 (KRAB-associated protein 1) as a novel Lin28A-binding protein using affinity purification and mass spectrometry. Kap1 specifically interacted with the N-terminal region of Lin28A through its coiled-coil domain. Kap1 overexpression significantly attenuated Lin28A ubiquitination and increased its stability. However, small interfering RNA-mediated knockdown of Kap1 promoted the ubiquitination of Lin28A, leading to its proteasomal degradation. Trim71, an E3 ubiquitin ligase, induced Lin28A degradation and Kap1 knockdown accelerated the Trim71-dependent degradation of Lin28A. Mutation of the lysine 177 residue of Lin28A to arginine abrogated the ubiquitination and degradation of Lin28A which were accelerated by Kap1 silencing. Moreover, Kap1 overexpression led to the accumulation of Lin28A in the cytoplasm, but not in the nucleus, and reduced the levels of let-7 subtypes. These results suggest that Kap1 plays a key role in regulation of the stability of Lin28A by modulating the Trim71-mediated ubiquitination and subsequent degradation of Lin28A, thus playing a pivotal role in the regulation of ESC self-renewal and pluripotency.


Assuntos
Células-Tronco Embrionárias , Células-Tronco Pluripotentes Induzidas , Animais , Células-Tronco Embrionárias/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Mamíferos , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Fatores de Transcrição/metabolismo , Ubiquitinação
4.
Int J Mol Sci ; 24(4)2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36834717

RESUMO

We investigated the role of a sirolimus-embedded silk microneedle (MN) wrap as an external vascular device for drug delivery efficacy, inhibition of neointimal hyperplasia, and vascular remodeling. Using dogs, a vein graft model was developed to interpose the carotid or femoral artery with the jugular or femoral vein. The control group contained four dogs with only interposed grafts; the intervention group contained four dogs with vein grafts in which sirolimus-embedded silk-MN wraps were applied. After 12-weeks post-implantation, 15 vein grafts in each group were explanted and analyzed. Vein grafts applied with the rhodamine B-embedded silk-MN wrap showed far higher fluorescent signals than those without the wrap. The diameter of vein grafts in the intervention group decreased or remained stable without dilatation; however, it increased in the control group. The intervention group had femoral vein grafts with a significantly lower mean neointima-to-media ratio, and had vein grafts with an intima layer showing a significantly lower collagen density ratio than the control group. In conclusion, sirolimus-embedded silk-MN wrap in a vein graft model successfully delivered the drug to the intimal layer of the vein grafts. It prevented vein graft dilatation, avoiding shear stress and decreasing wall tension, and it inhibited neointimal hyperplasia.


Assuntos
Neointima , Sirolimo , Animais , Cães , Neointima/prevenção & controle , Hiperplasia , Sirolimo/farmacologia , Artérias Carótidas , Sistemas de Liberação de Medicamentos
5.
Int J Mol Sci ; 24(12)2023 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-37373457

RESUMO

Epithelial ovarian cancer (EOC) is the most lethal gynecological malignancy owing to relapse caused by resistance to chemotherapy. We previously reported that cluster of differentiation 109 (CD109) expression is positively correlated with poor prognosis and chemoresistance in patients with EOC. To further explore the role of CD109 in EOC, we explored the signaling mechanism of CD109-induced drug resistance. We found that CD109 expression was upregulated in doxorubicin-resistant EOC cells (A2780-R) compared with that in their parental cells. In EOC cells (A2780 and A2780-R), the expression level of CD109 was positively correlated with the expression level of ATP-binding cassette (ABC) transporters, such as ABCB1 and ABCG2, and paclitaxel (PTX) resistance. Using a xenograft mouse model, it was confirmed that PTX administration in xenografts of CD109-silenced A2780-R cells significantly attenuated in vivo tumor growth. The treatment of CD109-overexpressed A2780 cells with cryptotanshinone (CPT), a signal transducer and activator of transcription 3 (STAT3) inhibitor, inhibited the CD109 overexpression-induced activation of STAT3 and neurogenic locus notch homolog protein 1 (NOTCH1), suggesting a STAT3-NOTCH1 signaling axis. The combined treatment of CD109-overexpressed A2780 cells with CPT and N-[N-(3,5-difluorophenacetyl)-l-alanyl]-S-phenylglycine t-butyl ester (DAPT), a NOTCH inhibitor, markedly abrogated PTX resistance. These results suggest that CD109 plays a key role in the acquisition of drug resistance by activating the STAT3-NOTCH1 signaling axis in patients with EOC.


Assuntos
Neoplasias Ovarianas , Humanos , Feminino , Animais , Camundongos , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Fator de Transcrição STAT3/metabolismo , Linhagem Celular Tumoral , Recidiva Local de Neoplasia , Paclitaxel/farmacologia , Carcinoma Epitelial do Ovário/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Transportadores de Cassetes de Ligação de ATP , Proteínas de Neoplasias/metabolismo , Antígenos CD/uso terapêutico , Proteínas Ligadas por GPI/metabolismo , Receptor Notch1/genética , Receptor Notch1/metabolismo
6.
Int J Mol Sci ; 24(7)2023 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-37047234

RESUMO

NANOG, a stemness-associated transcription factor, is highly expressed in many cancers and plays a critical role in regulating tumorigenicity. Transformation/transcription domain-associated protein (TRRAP) has been reported to stimulate the tumorigenic potential of cancer cells and induce the gene transcription of NANOG. This study aimed to investigate the role of the TRRAP-NANOG signaling pathway in the tumorigenicity of cancer stem cells. We found that TRRAP overexpression specifically increases NANOG protein stability by interfering with NANOG ubiquitination mediated by FBXW8, an E3 ubiquitin ligase. Mapping of NANOG-binding sites using deletion mutants of TRRAP revealed that a domain of TRRAP (amino acids 1898-2400) is responsible for binding to NANOG and that the overexpression of this TRRAP domain abrogated the FBXW8-mediated ubiquitination of NANOG. TRRAP knockdown decreased the expression of CD44, a cancer stem cell marker, and increased the expression of P53, a tumor suppressor gene, in HCT-15 colon cancer cells. TRRAP depletion attenuated spheroid-forming ability and cisplatin resistance in HCT-15 cells, which could be rescued by NANOG overexpression. Furthermore, TRRAP knockdown significantly reduced tumor growth in a murine xenograft transplantation model, which could be reversed by NANOG overexpression. Together, these results suggest that TRRAP plays a pivotal role in the regulation of the tumorigenic potential of colon cancer cells by modulating NANOG protein stability.


Assuntos
Neoplasias do Colo , Animais , Humanos , Camundongos , Carcinogênese/genética , Linhagem Celular Tumoral , Neoplasias do Colo/patologia , Regulação Neoplásica da Expressão Gênica , Proteína Homeobox Nanog/genética , Proteína Homeobox Nanog/metabolismo , Células-Tronco Neoplásicas/metabolismo , Estabilidade Proteica
7.
Physiol Plant ; 174(2): e13677, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35316541

RESUMO

In wheat (Triticum aestivum L.), the floret development stage is an important step in determining grain yield per spike; however, the molecular mechanisms underlying floret development remain unclear. In this study, we elucidated the role of TaF-box2, a member of the F-box-containing E3 ubiquitin protein ligases, which is involved in floret development and anthesis of wheat. TaF-box2 was transiently expressed in the plasma membrane and cytoplasm of both tobacco and wheat. We also found that the SCFF-box2 (Skp1-Cul1-Rbx1-TaF-box2) ubiquitin ligase complex mediated self-ubiquitination activity. Transgenic Arabidopsis plants that constitutively overexpressed TaF-box2 showed markedly greater hypocotyl and root length than wild-type plants, and produced early flowering phenotypes. Flowering-related genes were significantly upregulated in TaF-box2-overexpressing Arabidopsis plants. Further protein interaction analyses such as yeast two-hybrid, in vitro pull-down, and bimolecular fluorescence complementation assays confirmed that TaF-box2 physically interacted with TaCYCL1 (Triticum aestivum cyclin-L1-1). Ubiquitination and degradation assays demonstrated that TaCYCL1 was ubiquitinated by SCFF-box2 and degraded through the 26S proteasome complex. The physiological functions of the TaF-box2 protein remain unclear; however, we discuss several potential routes of involvement in various physiological mechanisms which counteract flowering in transgenic Arabidopsis plants.


Assuntos
Arabidopsis , Proteínas F-Box , Arabidopsis/metabolismo , Proteínas F-Box/genética , Proteínas F-Box/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Triticum/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
8.
J Nanobiotechnology ; 20(1): 17, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34983551

RESUMO

The topographical interface of the extracellular environment has been appreciated as a principal biophysical regulator for modulating cell functions, such as adhesion, migration, proliferation, and differentiation. Despite the existed approaches that use two-dimensional nanomaterials to provide beneficial effects, opportunities evaluating their impact on stem cells remain open to elicit unprecedented cellular responses. Herein, we report an ultrathin cell-culture platform with potential-responsive nanoscale biointerfaces for monitoring mesenchymal stem cells (MSCs). We designed an intriguing nanostructured array through self-assembly of graphene oxide sheets and subsequent lithographical patterning method to produce chemophysically defined regions. MSCs cultured on anisotropic micro/nanoscale patterned substrate were spontaneously organized in a highly ordered configuration mainly due to the cell-repellent interactions. Moreover, the spatially aligned MSCs were spontaneously differentiated into smooth muscle cells upon the specific crosstalk between cells. This work provides a robust strategy for directing stem cells and differentiation, which can be utilized as a potential cell culture platform to understand cell-substrate or cell-cell interactions, further developing tissue repair and stem cell-based therapies.


Assuntos
Diferenciação Celular/fisiologia , Células-Tronco Mesenquimais/citologia , Miócitos de Músculo Liso/citologia , Nanoestruturas/química , Engenharia Tecidual/métodos , Técnicas de Cultura de Células/instrumentação , Técnicas de Cultura de Células/métodos , Grafite/química , Humanos , Fenótipo , Propriedades de Superfície , Engenharia Tecidual/instrumentação
9.
Sensors (Basel) ; 22(24)2022 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-36560040

RESUMO

An electrical impedance spectroscopy (EIS) experiment was performed using a double-shell electrical model to investigate the feasibility of detecting physiological changes in lettuce leaves over 16 h. Four lettuce plants were used, and the impedance spectra of the leaves were measured five times per plant every hour at frequencies of 500 Hz and 300 kHz. Estimated R-C parameters were computed, and the results show that the lettuce leaves closely fit the double-shell model (DSM). The average resistance ratios of R1 = 10.66R4 and R1 = 3.34R2 show high resistance in the extracellular fluid (ECF). A rapid increase in resistance (R1, R2, and R4) and a decrease in capacitance (C3 and C5) during water uptake were observed. In contrast, a gradual decrease in resistance and an increase in capacitance were observed while the LED light was on. Comparative studies of leaf physiology and electrical value changes support the idea that EIS is a great technique for the early monitoring of plant growth for crop production.


Assuntos
Espectroscopia Dielétrica , Lactuca , Espectroscopia Dielétrica/métodos , Agricultura , Fazendas , Plantas , Folhas de Planta/fisiologia , Impedância Elétrica
10.
Nano Lett ; 21(18): 7512-7518, 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34491741

RESUMO

Plasmonic electrochromism, a change in the localized surface plasmon resonance (LSPR) with an applied electric potential, has been attracting increasing attention for the development of spectroscopic tools or optoelectronic systems. There is a consensus on the mechanism of plasmonic electrochromism based on the classical capacitor and the Drude model. However, the electrochromic behaviors of metallic nanoparticles in narrow optical windows have been demonstrated only with small monotonic LSPR shifts, which limits the use of the electrochromism. Here, we observed three distinct electrochromic behaviors of gold nanocubes with a wide potential range through in situ dark-field electrospectroscopy. Interestingly, the nanocubes show a faster frequency shift under the highly negative potential, and this opens the possibility of largely tunable electrochromic LSPR shifts. The reversibility of the electrochemical switching with these cubes are also shown. We attribute this unexpected change beyond classical understandings to the material-specific quantum mechanical electronic structures of the plasmonic materials.

11.
Int J Mol Sci ; 23(2)2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35055132

RESUMO

Anterior gradient protein 2 homolog (AGR2), an endoplasmic reticulum protein, is secreted in the tumor microenvironment. AGR2 is a member of the disulfide isomerase family, is highly expressed in multiple cancers, and promotes cancer metastasis. In this study, we found that etravirine, which is a non-nucleoside reverse transcriptase inhibitor, could induce AGR2 degradation via autophagy. Moreover, etravirine diminished proliferation, migration, and invasion in vitro. Moreover, in an orthotopic xenograft mouse model, the combination of etravirine and paclitaxel significantly suppressed cancer progression and metastasis. This drug may be a promising therapeutic agent for the treatment of ovarian cancer.


Assuntos
Mucoproteínas/metabolismo , Nitrilas/administração & dosagem , Proteínas Oncogênicas/metabolismo , Neoplasias Ovarianas/tratamento farmacológico , Paclitaxel/administração & dosagem , Pirimidinas/administração & dosagem , Inibidores da Transcriptase Reversa/administração & dosagem , Animais , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sinergismo Farmacológico , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Mucoproteínas/genética , Metástase Neoplásica , Nitrilas/farmacologia , Proteínas Oncogênicas/genética , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Paclitaxel/farmacologia , Proteólise , Pirimidinas/farmacologia , Inibidores da Transcriptase Reversa/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Korean J Physiol Pharmacol ; 26(5): 357-365, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36039736

RESUMO

Simultaneous myofibril and mitochondrial development is crucial for the cardiac differentiation of pluripotent stem cells (PSCs). Specifically, mitochondrial energy metabolism (MEM) development in cardiomyocytes is essential for the beating function. Although previous studies have reported that MEM is correlated with cardiac differentiation, the process and timing of MEM regulation for cardiac differentiation remain poorly understood. Here, we performed transcriptome analysis of cells at specific stages of cardiac differentiation from mouse embryonic stem cells (mESCs) and human induced PSCs (hiPSCs). We selected MEM genes strongly upregulated at cardiac lineage commitment and in a time-dependent manner during cardiac maturation and identified the protein-protein interaction networks. Notably, MEM proteins were found to interact closely with cardiac maturation-related proteins rather than with cardiac lineage commitment-related proteins. Furthermore, MEM proteins were found to primarily interact with cardiac muscle contractile proteins rather than with cardiac transcription factors. We identified several candidate MEM regulatory genes involved in cardiac lineage commitment (Cck, Bdnf, Fabp4, Cebpα, and Cdkn2a in mESC-derived cells, and CCK and NOS3 in hiPSC-derived cells) and cardiac maturation (Ppargc1α, Pgam2, Cox6a2, and Fabp3 in mESC-derived cells, and PGAM2 and SLC25A4 in hiPSC-derived cells). Therefore, our findings show the importance of MEM in cardiac maturation.

13.
Stroke ; 52(1): 331-334, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33272132

RESUMO

BACKGROUND AND PURPOSE: The association between intracranial aneurysms (IAs) and Marfan syndrome (MFS) is controversial. We aimed to evaluate the prevalence and characteristics of IAs in patients with MFS using brain imaging and compare it with the general population. METHODS: Between 2007 and 2020, 118 patients with confirmed MFS who underwent brain imaging were enrolled and classified into 2 groups; IA group versus non-IA. Demographic data were acquired from their medical records, including age, sex, comorbidities, and aortic diseases. Two readers reviewed all brain images independently regarding the presence, morphology, size, and location of IAs. All data were compared between both groups, and IA characteristics in MFS were analyzed using a database of controls with IAs. RESULTS: The prevalence of IAs was 11.9% in patients with MFS. IA group were significantly older in age (44.6±12.1 years in IA versus 36.8±14.0 years in non-IA, P=0.039) and had female predominance (71.4% in IA versus 43.3% in non-IA, P=0.047). All IAs were unruptured, and there was no subarachnoid hemorrhage during the follow-up period (mean; 53.5±43.3 months). The mean diameter of IAs was significantly larger (4.23±1.80 mm in MFS versus 3.04±1.57 mm in control, P=0.004). IAs with MFS were frequently located in the vertebrobasilar artery (33.3% in MFS versus 2.1% in control, P=0.002) and more common in fusiform morphology (13.3% in MFS versus 1.1% in control, P=0.048). CONCLUSIONS: This large-cohort study demonstrated a high prevalence and differential features of IAs in MFS, which may support the association between IAs and MFS.


Assuntos
Encéfalo/diagnóstico por imagem , Aneurisma Intracraniano/etiologia , Síndrome de Marfan/complicações , Adulto , Idoso , Aneurisma Roto , Estudos de Coortes , Angiografia por Tomografia Computadorizada , Feminino , Seguimentos , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/epidemiologia , Angiografia por Ressonância Magnética , Masculino , Síndrome de Marfan/diagnóstico por imagem , Síndrome de Marfan/epidemiologia , Pessoa de Meia-Idade , Prevalência
14.
Biochem Biophys Res Commun ; 552: 164-169, 2021 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-33751933

RESUMO

Human mesenchymal stem cells (MSCs) are known to have anti-inflammatory and immunomodulatory functions; thus, several MSC products have been applied as cell therapy in clinical trials worldwide. Recent studies have demonstrated that MSC spheroids have superior anti-inflammatory and immunomodulatory functions to a single cell suspension. Current methods to prepare MSC spheroids include hanging drop, concave microwell aggregation, spinner flask, and gravity circulation. However, all these methods have limitations such as low scalability, easy cell clumping, low viability, and irregular size distribution. Here, we present a nano-patterned culture plasticware named PAMcell™ 3D plate to overcome these limitations. Nano-sized silica particles (700 nm) coated with RGD peptide were arrayed into fusiform onto the PLGA film. This uniform array enabled the seeded MSCs to grow only on the silica particles, forming uniform-sized semi-spheroids within 48 h. These MSC spheroids have been shown to have enhanced stemness, anti-inflammatory, and immunomodulatory functions, as revealed by the increased expression of stem cell markers (Oct4, Sox2, and Nanog), anti-inflammatory (IL-10, TSG6, and IDO), and immunomodulatory molecules (HGF, VEGF, CXCR4) both at mRNA and protein expression levels. Furthermore, these MSC spheroids demonstrated an increased palliative effect on glycemic control in a multiple low-dose streptozotocin-induced diabetes model compared with the same number of MSC single cell suspensions. Taken together, this study presents a new method to produce uniform-sized MSC spheroids with enhanced anti-inflammatory and immunomodulatory functions in vitro and in vivo.


Assuntos
Tecido Adiposo/citologia , Anti-Inflamatórios/imunologia , Técnicas de Cultura de Células/métodos , Fatores Imunológicos/imunologia , Células-Tronco Mesenquimais/imunologia , Esferoides Celulares/imunologia , Animais , Técnicas de Cultura de Células/instrumentação , Células Cultivadas , Diabetes Mellitus Experimental/imunologia , Diabetes Mellitus Experimental/terapia , Expressão Gênica/imunologia , Humanos , Masculino , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Camundongos Endogâmicos C57BL , Esferoides Celulares/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/imunologia , Fatores de Transcrição/metabolismo
15.
FASEB J ; 34(1): 1231-1246, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31914695

RESUMO

Endothelial progenitor cells (EPCs) promote neovascularization and tissue repair by migrating to vascular injury sites; therefore, factors that enhance EPC homing to damaged tissues are of interest. Here, we provide evidence of the prominent role of the Netrin-4 (NTN4)-Unc-5 Netrin receptor B (UNC5B) axis in EPC-specific promotion of ischemic neovascularization. Our results showed that NTN4 promoted the proliferation, chemotactic migration, and paracrine effects of small EPCs (SEPCs) and significantly increased the incorporation of large EPCs (LEPCs) into tubule networks. Additionally, NTN4 prominently augmented neovascularization in mice with hindlimb ischemia by increasing the homing of exogenously transplanted EPCs to the ischemic limb and incorporating EPCs into vessels. Moreover, silencing of UNC5B, an NTN4 receptor, abrogated the NTN4-induced cellular activities of SEPCs in vitro and blood-flow recovery and neovascularization in vivo in ischemic muscle by reducing EPC homing and incorporation. These findings suggest NTN4 as an EPC-based therapy for treating angiogenesis-dependent diseases.


Assuntos
Células Progenitoras Endoteliais/metabolismo , Isquemia/metabolismo , Músculo Esquelético/metabolismo , Neovascularização Patológica/metabolismo , Receptores de Netrina/metabolismo , Netrinas/metabolismo , Animais , Células Progenitoras Endoteliais/patologia , Células Progenitoras Endoteliais/transplante , Inativação Gênica , Xenoenxertos , Membro Posterior/irrigação sanguínea , Humanos , Isquemia/genética , Isquemia/patologia , Isquemia/terapia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/patologia , Neovascularização Patológica/genética , Neovascularização Patológica/patologia , Neovascularização Patológica/terapia , Receptores de Netrina/genética , Netrinas/genética
16.
Langmuir ; 37(48): 14205-14213, 2021 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-34806387

RESUMO

The lateral size effect of graphene oxide (GO) on surfaced-enhanced Raman scattering (SERS) property is systematically investigated by using size-fractionalized GO. For the size fractionalization without changes of chemical structure, large-sized GO (LGO) and small-sized GO (SGO) are separated from the as-synthesized GO (AGO) by centrifugation and membrane filtration, respectively. The size-fractionalized GO sheets are immobilized on a solid substrate for the parallel comparison of their SERS property. As a result, we find that LGO shows considerably higher SERS property than SGO for typical Raman probes such as rhodamine 6G and crystal violet. Furthermore, the lateral size effect of GO derivatives is consistently observed when they are hybridized with plasmonic silver nanoparticles. These results indicate that LGO is superior to AGO and SGO as a SERS platform, and it is also quantitatively confirmed by calculating their enhancement factor.

17.
Arterioscler Thromb Vasc Biol ; 40(4): e105-e113, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32075417

RESUMO

OBJECTIVE: Vascular progenitor cells (VPCs), which are able to differentiate into both endothelial cells and smooth muscle cells, have the potential for treatment of ischemic diseases. Generated by pluripotent stem cells, VPCs carry the risk of tumorigenicity in clinical application. This issue could be resolved by direct lineage conversion, the induction of functional cells from another lineage by using only lineage-restricted transcription factors. Here, we show that induced VPCs (iVPCs) can be generated from fibroblasts by ETS (E-twenty six) transcription factors, Etv2 and Fli1. Approach and Results: Mouse fibroblasts were infected with lentivirus encoding Etv2 and Fli1. Cell colonies appeared in Fli1- and Etv2/Fli1-infected groups and were mechanically picked. The identity of cell colonies was confirmed by proliferation assay and reverse-transcription polymerase chain reaction with vascular markers. Etv2/Fli1- infected cell colonies were sorted by CD144 (also known as CDH5, VE-cadherin). We defined that CD144-positive iVPCs maintained its own population and expanded stably at multiple passages. iVPCs could differentiate into functional endothelial cells and smooth muscle cells by a defined medium. The functionalities of iVPC-derived endothelial cells and smooth muscle cells were confirmed by analyzing LDL (low-density lipoprotein) uptake, carbachol-induced contraction, and tube formation in vitro. Transplantation of iVPCs into the ischemic hindlimb model enhanced blood flow without tumor formation in vivo. Human iVPCs were generated by human ETS transcription factors ETV2 and FLI1. CONCLUSIONS: We demonstrate that ischemic disease curable iVPCs, which have self-renewal and bipotency, can be generated from mouse fibroblasts by enforced ETS family transcription factors, Etv2 and Fli1 expression. Our simple strategy opens insights into stem cell-based ischemic disease therapy.


Assuntos
Fibroblastos/citologia , Isquemia/fisiopatologia , Proteína Proto-Oncogênica c-fli-1/fisiologia , Células-Tronco/fisiologia , Fatores de Transcrição/fisiologia , Animais , Antígenos CD , Caderinas , Diferenciação Celular , Linhagem Celular , Proliferação de Células , Modelos Animais de Doenças , Células Endoteliais/citologia , Membro Posterior/irrigação sanguínea , Isquemia/terapia , Miócitos de Músculo Liso/citologia , Transplante de Células-Tronco , Células-Tronco/imunologia
18.
Chem Rev ; 119(24): 12208-12278, 2019 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-31794202

RESUMO

Plasmonic nanostructures possessing unique and versatile optoelectronic properties have been vastly investigated over the past decade. However, the full potential of plasmonic nanostructure has not yet been fully exploited, particularly with single-component homogeneous structures with monotonic properties, and the addition of new components for making multicomponent nanoparticles may lead to new-yet-unexpected or improved properties. Here we define the term "multi-component nanoparticles" as hybrid structures composed of two or more condensed nanoscale domains with distinctive material compositions, shapes, or sizes. We reviewed and discussed the designing principles and synthetic strategies to efficiently combine multiple components to form hybrid nanoparticles with a new or improved plasmonic functionality. In particular, it has been quite challenging to precisely synthesize widely diverse multicomponent plasmonic structures, limiting realization of the full potential of plasmonic heterostructures. To address this challenge, several synthetic approaches have been reported to form a variety of different multicomponent plasmonic nanoparticles, mainly based on heterogeneous nucleation, atomic replacements, adsorption on supports, and biomolecule-mediated assemblies. In addition, the unique and synergistic features of multicomponent plasmonic nanoparticles, such as combination of pristine material properties, finely tuned plasmon resonance and coupling, enhanced light-matter interactions, geometry-induced polarization, and plasmon-induced energy and charge transfer across the heterointerface, were reported. In this review, we comprehensively summarize the latest advances on state-of-art synthetic strategies, unique properties, and promising applications of multicomponent plasmonic nanoparticles. These plasmonic nanoparticles including heterostructured nanoparticles and composite nanostructures are prepared by direct synthesis and physical force- or biomolecule-mediated assembly, which hold tremendous potential for plasmon-mediated energy transfer, magnetic plasmonics, metamolecules, and nanobiotechnology.

19.
Plant Cell Rep ; 40(3): 543-558, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33423075

RESUMO

KEY MESSAGE: We identified a RING-type E3 ligase (TaBAH1) protein in winter wheat that targets TaSAHH1 for degradation and might be involved in primordia development by regulating targeted protein degradation. Grain yield per spike in wheat (Triticum aestivum), is mainly determined prior to flowering during mature primordia development; however, the genes involved in primordia development have yet to be characterized. In this study, we demonstrated that, after vernalization for 50 days at 4 °C, there was a rapid acceleration in primordia development to the mature stages in the winter wheat cultivars Keumgang and Yeongkwang compared with the Chinese Spring cultivar. Although Yeongkwang flowers later than Keumgang under normal condition, it has the same heading time and reaches the WS9 stage of floral development after vernalization for 50 days. Using RNA sequencing, we identified candidate genes associated with primordia development in cvs. Keumgang and Yeongkwang, that are differentially expressed during wheat reproductive stages. Among these, the RING-type E3 ligase TaBAH1 (TraesCS5B01G373000) was transcriptionally upregulated between the double-ridge (WS2.5) stage and later stages of floret primordia development (WS10) after vernalization. Transient expression analysis indicated that TaBAH1 was localized to the plasma membrane and nucleus and was characterized by self-ubiquitination activity. Furthermore, we found that TaBAH1 interacts with TaSAHH1 to mediate its polyubiquitination and degradation through a 26S proteasomal pathway. Collectively, the findings of this study indicate that TaBAH1 might play a prominent role in post-vernalization floret primordia development.


Assuntos
Flores/crescimento & desenvolvimento , Proteínas de Plantas/genética , Triticum/genética , Ubiquitina-Proteína Ligases/genética , Flores/genética , Flores/fisiologia , Regulação da Expressão Gênica de Plantas , Filogenia , Proteínas de Plantas/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Fatores de Tempo , Triticum/fisiologia , Ubiquitina-Proteína Ligases/fisiologia , Ubiquitinação
20.
Mar Drugs ; 19(5)2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33922418

RESUMO

Scleroderma is an autoimmune disease caused by the abnormal regulation of extracellular matrix synthesis and is activated by non-regulated inflammatory cells and cytokines. Echinochrome A (EchA), a natural pigment isolated from sea urchins, has been demonstrated to have antioxidant activities and beneficial effects in various disease models. The present study demonstrates for the first time that EchA treatment alleviates bleomycin-induced scleroderma by normalizing dermal thickness and suppressing collagen deposition in vivo. EchA treatment reduces the number of activated myofibroblasts expressing α-SMA, vimentin, and phosphorylated Smad3 in bleomycin-induced scleroderma. In addition, it decreased the number of macrophages, including M1 and M2 types in the affected skin, suggesting the induction of an anti-inflammatory effect. Furthermore, EchA treatment markedly attenuated serum levels of inflammatory cytokines, such as tumor necrosis factor-α and interferon-γ, in a murine scleroderma model. Taken together, these results suggest that EchA is highly useful for the treatment of scleroderma, exerting anti-fibrosis and anti-inflammatory effects.


Assuntos
Anti-Inflamatórios/farmacologia , Macrófagos/efeitos dos fármacos , Miofibroblastos/efeitos dos fármacos , Naftoquinonas/farmacologia , Escleroderma Sistêmico/prevenção & controle , Pele/efeitos dos fármacos , Actinas/metabolismo , Animais , Bleomicina , Colágeno/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Fibrose , Humanos , Mediadores da Inflamação/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Macrófagos/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Miofibroblastos/imunologia , Miofibroblastos/metabolismo , Miofibroblastos/patologia , Fosforilação , Células RAW 264.7 , Escleroderma Sistêmico/induzido quimicamente , Escleroderma Sistêmico/imunologia , Escleroderma Sistêmico/metabolismo , Pele/imunologia , Pele/metabolismo , Pele/patologia , Proteína Smad3/metabolismo , Vimentina/metabolismo
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