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1.
Macromol Rapid Commun ; 43(5): e2100747, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34967476

RESUMEN

3D pyramidal polymer single crystals provide spatial gradient variations within the crystal molecules, and these variations facilitate the study of the relationship between structure and properties within the molecules of various complexes with anisotropic structures. As described herein, a low-temperature-assisted microfluidic pore channeling approach is proposed to prepare structurally ordered polymer single crystals. A mixture of dichloromethane and dimethyl sulfoxide is used as a prepolymer, and a liquid microfluidic technique is employed to grow the end-functionalized polymers into 3D polymer single crystals. Through the ordered growth of single crystals, a personalized pyramidal pattern with a homogeneous structure is formed. To evaluate the mesh node density, low-temperature growth time and substrate type are also investigated. Rectangular, pyramidal, and dendritic patterns are synthesized via low-temperature single crystal growth. This work shows that low temperature-assisted microfluidics provides a novel means to tune the 3D structure of polymer single crystals.


Asunto(s)
Cristales Líquidos , Microfluídica , Cristalización , Cristales Líquidos/química , Polímeros/química , Temperatura
2.
J Cell Mol Med ; 25(3): 1700-1711, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33438362

RESUMEN

Wet age-related macular degeneration (wAMD), characterized by choroidal neovascularization (CNV), is a leading cause of irreversible vision loss among elderly people in developed nations. Subretinal fibrosis, mediated by epithelial-mesenchymal transition (EMT) of retinal pigment epithelium (RPE) cells, leads to unsuccessful anti-vascular endothelial growth factor (VEGF) agent treatments in CNV patients. Under hypoxic conditions, hypoxia-inducible factor-1α (HIF-1α) increases the stability and activation of p53, which activates microRNA-34a (miRNA-34a) transcription to promote fibrosis. Additionally, Klotho is a target gene of miRNA-34a that inhibits fibrosis. This study aimed to explore the role of the HIF-1α/p53/miRNA-34a/Klotho axis in subretinal fibrosis and CNV. Hypoxia-induced HIF-1α promoted p53 stability, phosphorylation and nuclear translocation in ARPE-19 cells (a human RPE cell line). HIF-1α-dependent p53 activation up-regulated miRNA-34a expression in ARPE-19 cells following hypoxia. Moreover, hypoxia-induced p53-dependent miRNA-34a inhibited the expression of Klotho in ARPE-19 cells. Additionally, the HIF-1α/p53/miRNA-34a/Klotho axis facilitated hypoxia-induced EMT in ARPE-19 cells. In vivo, blockade of the HIF-1α/p53/miRNA-34a/Klotho axis alleviated the formation of mouse laser-induced CNV and subretinal fibrosis. In short, the HIF-1α/p53/miRNA-34a/Klotho axis in RPE cells promoted subretinal fibrosis, thus aggravating the formation of CNV.


Asunto(s)
Neovascularización Coroidal/etiología , Neovascularización Coroidal/metabolismo , Glucuronidasa/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , MicroARNs/genética , Epitelio Pigmentado de la Retina/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Animales , Línea Celular , Neovascularización Coroidal/diagnóstico por imagen , Neovascularización Coroidal/patología , Modelos Animales de Enfermedad , Células Epiteliales/metabolismo , Fibrosis , Regulación de la Expresión Génica , Humanos , Hipoxia/metabolismo , Proteínas Klotho , Ratones , Modelos Biológicos , Fosforilación , Estabilidad Proteica , Transporte de Proteínas , Epitelio Pigmentado de la Retina/diagnóstico por imagen , Epitelio Pigmentado de la Retina/patología , Transducción de Señal
3.
J Cell Mol Med ; 25(14): 6709-6720, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34057287

RESUMEN

Neovascular age-related macular degeneration (AMD), which is characterized by choroidal neovascularization (CNV), leads to vision loss. M2 macrophages produce vascular endothelial growth factor (VEGF), which aggravates CNV formation. The histone acetyltransferase p300 enhances the stability of spliced X-box binding protein 1 (XBP1s) and promotes the transcriptional activity of the XBP1s target gene homocysteine inducible endoplasmic reticulum protein with ubiquitin-like domain 1 (Herpud1). Herpud1 promotes the M2 polarization of macrophages. This study aimed to explore the roles of the p300/XBP1s/Herpud1 axis in the polarization of macrophages and the pathogenesis of CNV. Hypoxia-induced p300 interacted with XBP1s to acetylate XBP1s in RAW264.7 cells. Additionally, hypoxia-induced p300 enhanced the XBP-1s-mediated unfolded protein response (UPR), alleviated the proteasome-dependent degradation of XBP1s and enhanced the transcriptional activity of XBP1s for Herpud1. The hypoxia-induced p300/XBP1s/Herpud1 axis facilitated RAW264.7 cell M2 polarization. Knockdown of the p300/XBP1s/Herpud1 axis in RAW264.7 cells inhibited the proliferation, migration and tube formation of mouse choroidal endothelial cells (MCECs). The p300/XBP1s/Herpud1 axis increased in infiltrating M2-type macrophages in mouse laser-induced CNV lesions. Blockade of the p300/XBP1s/Herpud1 axis inhibited macrophage M2 polarization and alleviated CNV lesions. Our study demonstrated that the p300/XBP1s/Herpud1 axis in infiltrating macrophages increased the M2 polarization of macrophages and the development of CNV.


Asunto(s)
Coroides/crecimiento & desarrollo , Neovascularización Coroidal/genética , Proteínas de la Membrana/genética , Proteína 1 de Unión a la X-Box/genética , Factores de Transcripción p300-CBP/genética , Animales , Coroides/metabolismo , Coroides/patología , Neovascularización Coroidal/patología , Modelos Animales de Enfermedad , Células Endoteliales/metabolismo , Humanos , Activación de Macrófagos/genética , Macrófagos/metabolismo , Ratones , Células RAW 264.7 , Transducción de Señal/genética , Factor A de Crecimiento Endotelial Vascular/genética
4.
Exp Eye Res ; 213: 108823, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34752817

RESUMEN

Choroidal neovascularization (CNV), a feature of neovasular age-related macular degeneration (AMD), acts as a leading cause of vision loss in the elderly. Shikonin (SHI), a natural bioactive compound extracted from Chinese herb radix arnebiae, exerts anti-inflammatory and anti-angiogenic roles and also acts as a potential pyruvate kinase M2 (PKM2) inhibitor in macrophages. The major immune cells macrophages infiltrate the CNV lesions, where the production of pro-angiognic cytokines from macrophage facilitates the development of CNV. PKM2 contributes to the neovascular diseases. In this study, we found that SHI oral gavage alleviated the leakage, area and volume of mouse laser-induced CNV lesion and inhibited macrophage infiltration without ocular cytotoxicity. Moreover, SHI inhibited the secretion of pro-angiogenic cytokine, including basic fibroblast growth factor (FGF2), insulin-like growth factor-1 (IGF1), chemokine (C-C motif) ligand 2 (CCL2), placental growth factor and vascular endothelial growth factor (VEGF), from primary human macrophages by down-regulating PKM2/STAT3/CD163 pathway, indicating a novel potential therapy strategy for CNV.


Asunto(s)
Inhibidores de la Angiogénesis/uso terapéutico , Antiinflamatorios no Esteroideos/uso terapéutico , Neovascularización Coroidal/tratamiento farmacológico , Macrófagos/efectos de los fármacos , Naftoquinonas/uso terapéutico , Piruvato Quinasa/antagonistas & inhibidores , Inductores de la Angiogénesis/metabolismo , Animales , Antígenos CD/metabolismo , Antígenos de Diferenciación Mielomonocítica/metabolismo , Western Blotting , Células Cultivadas , Neovascularización Coroidal/enzimología , Cromatografía Líquida de Alta Presión , Colorantes/administración & dosificación , Citocinas/metabolismo , Modelos Animales de Enfermedad , Medicamentos Herbarios Chinos/uso terapéutico , Ensayo de Inmunoadsorción Enzimática , Angiografía con Fluoresceína , Humanos , Etiquetado Corte-Fin in Situ , Verde de Indocianina/administración & dosificación , Macrófagos/enzimología , Masculino , Ratones , Ratones Endogámicos C57BL , Fosforilación , Piruvato Quinasa/metabolismo , Receptores de Superficie Celular/antagonistas & inhibidores , Receptores de Superficie Celular/metabolismo , Factor de Transcripción STAT3/antagonistas & inhibidores , Factor de Transcripción STAT3/metabolismo
5.
J Cell Physiol ; 235(11): 8724-8735, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32324260

RESUMEN

Diabetic retinopathy (DR) is the most common ocular complication caused by diabetes mellitus and is the main cause of visual impairment in working-age people. Reactive gliosis and pro-inflammatory cytokine production by Müller cells contribute to the progression of DR. Melatonin is a strong anti-inflammatory hormone, mediating the cytoprotective effect of a variety of retinal cells against hyperglycemia. In this study, melatonin inhibited the gliosis activation and inflammatory cytokine production of Müller cells in both in vitro and in vivo models of DR. The melatonin membrane blocker, Luzindole, invalidated the melatonin-mediated protective effect on Müller cells. Furthermore, melatonin inhibited Müller cell activation and pro-inflammatory cytokine production by upregulating the long noncoding RNA maternally expressed gene 3/miR-204/sirtuin 1 axis. In conclusion, our study suggested that melatonin treatment could be a novel therapeutic strategy for DR.


Asunto(s)
Citocinas/efectos de los fármacos , Retinopatía Diabética/tratamiento farmacológico , Células Ependimogliales/efectos de los fármacos , Melatonina/uso terapéutico , ARN Largo no Codificante/genética , Animales , Apoptosis/efectos de los fármacos , Citocinas/metabolismo , Diabetes Mellitus/tratamiento farmacológico , Diabetes Mellitus/metabolismo , Retinopatía Diabética/metabolismo , Células Ependimogliales/metabolismo , Hiperglucemia/tratamiento farmacológico , Hiperglucemia/metabolismo , Inflamación/metabolismo , Ratones Endogámicos C57BL , Activación Transcripcional/genética
6.
J Cell Physiol ; 235(2): 1259-1273, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31270802

RESUMEN

In age-related macular degeneration (AMD), choroidal neovascularization (CNV), a major pathologic feature of neovascular AMD (nAMD), affects 10% of patients, potentially causing serious complications, including vision loss. Vascular endothelial growth factor receptor 2 (VEGFR2) and fibroblast growth factor receptor 1 (FGFR1) contribute to the pathogenesis of CNV. Brivanib is an oral selective dual receptor tyrosine kinase (RTK) inhibitor of FGFRs and VEGFRs, especially VEGFR2 and FGFR1. In this study, brivanib inhibited zebrafish embryonic angiogenesis without impairing neurodevelopment. In a mouse CNV model, brivanib intravitreal injection blocked phosphorylation of FGFR1 and VEGFR2 and reduced CNV leakage, area, and formation without causing intraocular toxicity. Moreover, brivanib oral gavage reduced CNV leakage and area. Accordingly, brivanib remained at high concentrations (above 14,000 ng/ml) in retinal/choroidal/scleral tissues following intravitreal injection. Similarly, brivanib remained at high concentrations (over 10,000 ng/ml) in retinal/choroidal/scleral tissues following oral gavage. Finally, in vitro cell experiments demonstrated that brivanib inhibited the proliferation, migration and tube formation of microvascular endothelial cells. In conclusion, our study suggested that brivanib treatment could be a novel therapeutic strategy for nAMD.


Asunto(s)
Alanina/análogos & derivados , Neovascularización Coroidal/patología , Células Endoteliales/efectos de los fármacos , Inhibidores de Proteínas Quinasas/farmacología , Triazinas/farmacología , Degeneración Macular Húmeda/patología , Alanina/farmacología , Inhibidores de la Angiogénesis/farmacología , Animales , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Neovascularización Coroidal/metabolismo , Modelos Animales de Enfermedad , Rayos Láser , Masculino , Ratones , Ratones Endogámicos C57BL , Degeneración Macular Húmeda/metabolismo , Pez Cebra
7.
Exp Eye Res ; 199: 108185, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32841649

RESUMEN

Age-related cataract (ARC) is the leading cause of visual impairment or even blindness among the aged population globally. Long non-coding RNA (LncRNA) has been proven to be the potential regulator of ARC. The latest study reveals that maternally expressed gene 3 (MEG3) promotes the apoptosis and inhibits the proliferation of multiple cancer cells. However, the expression and role of MEG3 in ARC are unclear. In this study, we investigated the effects of MEG3 in ARC and explored the regulatory mechanisms underlying these effects. We observed that MEG3 expression was up-regulated in the age-related cortical cataract (ARCC) lens capsules and positively correlated with the histological degree of ARCC. The pro-apoptosis protein, active caspase-3 and Bax increased in the anterior lens capsules of ARCC tissue, while the anti-apoptotic protein Bcl-2 decreased compared to normal lens. Knockdown of MEG3 increased the viability and inhibited the apoptosis of LECs upon the oxidative stress induced by H2O2. MEG3 was localized in both nucleus and cytoplasm in LECs. MEG3 facilitated TP53INP1 expression via acting as miR-223 sponge and promoting P53 expression. Additionally, TP53INP1 knockdown alleviated H2O2-induced lens turbidity. In summary, MEG3 promoted ARC progression by up-regulating TP53INP1 expression through suppressing miR-223 and promoting P53 expression, which would provide a novel insight into the pathogenesis of ARC.


Asunto(s)
Proteínas Portadoras/genética , Catarata/genética , Regulación de la Expresión Génica , Proteínas de Choque Térmico/genética , Cristalino/metabolismo , ARN Largo no Codificante/genética , Regulación hacia Arriba , Anciano , Proteínas Portadoras/biosíntesis , Catarata/metabolismo , Catarata/patología , Proliferación Celular , Progresión de la Enfermedad , Femenino , Proteínas de Choque Térmico/biosíntesis , Humanos , Cristalino/patología , Masculino , Persona de Mediana Edad , ARN Largo no Codificante/biosíntesis , Transducción de Señal
8.
Exp Eye Res ; 196: 108065, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32407725

RESUMEN

Diabetic retinopathy (DR) is a neurovascular complication of diabetes mellitus that leads to blindness in the working-age population. Retinal Müller cells proliferate and produce pro-angiogenic factors, including vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF), via the reactive oxygen species (ROS)/thioredoxin interacting protein (TXNIP)/NACHT, LRR and PYD domain-containing protein 3 (NLRP3) inflammasome axis to promote proliferative DR. Epigallocatechin-3-gallate (EGCG) plays anti-oxidant, anti-inflammatory, anti-proliferative and anti-angiogenic roles in Müller cells. A prodrug of EGCG (pro-EGCG) enhances the bioavailability of EGCG. In an in vitro model of high glucose-stimulated Müller cells, pro-EGCG inhibited proliferation and pro-angiogenic factor production by down-regulating the activity of the ROS/TXNIP/NLRP3 inflammasome axis. In a mouse DR model, pro-EGCG reduced ROS accumulation, NLRP3 inflammasome activation, Müller cell proliferation, and production of the pro-angiogenic factors VEGF and HGF. In summary, pro-EGCG mitigated hyperglycaemia-challenged Müller cell proliferation and pro-angiogenic factor production by inhibiting ROS/TXNIP/NLRP3 inflammasome signalling, implying a potential therapeutic strategy for DR.


Asunto(s)
Inductores de la Angiogénesis/metabolismo , Proteínas Portadoras/antagonistas & inhibidores , Catequina/análogos & derivados , Células Ependimogliales/efectos de los fármacos , Glucosa/farmacología , Proteína con Dominio Pirina 3 de la Familia NLR/antagonistas & inhibidores , Especies Reactivas de Oxígeno/antagonistas & inhibidores , Tiorredoxinas/antagonistas & inhibidores , Animales , Western Blotting , Catequina/uso terapéutico , Recuento de Células , Proliferación Celular/efectos de los fármacos , Retinopatía Diabética/tratamiento farmacológico , Retinopatía Diabética/metabolismo , Ensayo de Inmunoadsorción Enzimática , Células Ependimogliales/metabolismo , Inflamasomas/efectos de los fármacos , Inflamasomas/metabolismo , Masculino , Malondialdehído/metabolismo , Ratones , Ratones Endogámicos C57BL , Profármacos/uso terapéutico , Sincalida/metabolismo , Superóxido Dismutasa/metabolismo , Transfección
9.
J Cell Mol Med ; 23(9): 6131-6139, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31282110

RESUMEN

Age-related cataract (ARC) is caused by the exposure of the lens to UVB which promotes oxidative damage and cell death. This study aimed to explore the role of lncRNA H19 in oxidative damage repair in early ARC. lncRNAs sequencing technique was used to identify different lncRNAs in the lens of early ARC patients. Human lens epithelial cells (HLECs) were exposed to ultraviolet irradiation; and 8-OHdG ELISA, Cell counting kit 8 (CCK8), EDU, flow cytometry and TUNEL assays were used to detect DNA damage, cell viability, proliferation and apoptosis. Luciferase assay was used to examine the interaction among H19, miR-29a and thymine DNA glycosylase (TDG) 3'UTR. We found that lncRNA H19 and TDG were highly expressed while miR-29a was down-regulated in the three types of early ARC and HLECs exposed to ultraviolet irradiation, compared to respective controls. lncRNA H19 knockdown aggravated oxidative damage, reduced cell viability and proliferation, and promoted apoptosis in HLECs, while lncRNA H19 overexpression led to opposite effects in HLECs. Mechanistically, miR-29a bound TDG 3'UTR to repress TDG expression. lncRNA H19 up-regulated the expression of TDG by repressing miR-29a because it acted as ceRNA through sponging miR-29a. In conclusion, the interaction among lncRNA H19, miR-29a and TDG is involved in early ARC. lncRNA H19 could be a useful marker of early ARC and oxidative damage repair pathway of lncRNA H19/miR-29a/TDG may be a promising target for the treatment of ARC.


Asunto(s)
Catarata/genética , MicroARNs/genética , ARN Largo no Codificante/genética , Timina ADN Glicosilasa/genética , Envejecimiento/genética , Envejecimiento/patología , Envejecimiento/efectos de la radiación , Apoptosis/genética , Catarata/metabolismo , Catarata/patología , Línea Celular , Proliferación Celular/genética , Supervivencia Celular/genética , Células Epiteliales/metabolismo , Células Epiteliales/patología , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Cristalino/metabolismo , Cristalino/efectos de la radiación , Estrés Oxidativo/genética , Estrés Oxidativo/efectos de la radiación , Transducción de Señal/efectos de la radiación , Rayos Ultravioleta/efectos adversos
10.
Mol Vis ; 25: 734-744, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31814699

RESUMEN

Purpose: Age-related cataract (ARC) is the leading cause of visual impairment and blindness worldwide. The apoptosis of lens epithelial cells (LECs) induced by oxidative damage is a major contributing factor to ARC. Long noncoding RNAs (lncRNAs) play important roles in various biologic processes. We aimed to explore the role of glutathione peroxidase 3 (GPX3)-antisense (AS) in ARCs. Methods: We extracted total RNAs from transparent and age-matched cataractous human lenses and detected lncRNA expression profiles using high-throughput RNA sequencing. The expression of GPX3-AS and GPX3 was detected by quantitative real-time PCR (qRT-PCR). Apoptotic proteins were detected by western blot and immunofluorescence. We treated SRA01/04 cells with H2O2 to mimic oxidative stress and induce cell apoptosis, which was analyzed by flow cytometry and TdT-mediated dUTP Nick-End Labeling (TUNEL) assay. The cell counting kit-8 (CCK-8) assay was used to detect the viability of SRA01/04 cells. The location of GPX3-AS was determined by fluorescence in situ hybridization (FISH) and cell nuclear and cytoplasmic RNA separation. Results: The lncRNA GPX3-AS, which is located in the nuclei of LECs, was downregulated in cataractous human lenses compared with control lenses, and proapoptotic proteins were expressed at high levels in the anterior lens capsules of ARC tissues. An in vitro study suggested that GPX3-AS inhibited H2O2-induced SRA01/04 cell apoptosis. As GPX3-AS is transcribed from the AS strand of the GPX3 gene locus, we further revealed its regulatory role in GPX3 expression. GPX3-AS was positively correlated with GPX3 expression. In addition, GPX3-AS inhibited H2O2-induced SRA01/04 cell apoptosis by upregulating GPX3 expression. Conclusions: In summary, our study revealed that GPX3-AS downregulated the apoptosis of LECs via promoting GPX3 expression, implying a novel therapeutic target for ARCs.


Asunto(s)
Envejecimiento/genética , Apoptosis/genética , Catarata/genética , Células Epiteliales/patología , Glutatión Peroxidasa/genética , Cristalino/patología , ARN Largo no Codificante/metabolismo , Regulación hacia Arriba/genética , Cápsula Anterior del Cristalino/metabolismo , Cápsula Anterior del Cristalino/patología , Apoptosis/efectos de los fármacos , Línea Celular , Núcleo Celular/efectos de los fármacos , Núcleo Celular/metabolismo , Células Epiteliales/metabolismo , Glutatión Peroxidasa/metabolismo , Humanos , Peróxido de Hidrógeno/toxicidad , ARN Largo no Codificante/genética , Regulación hacia Arriba/efectos de los fármacos
11.
Exp Cell Res ; 373(1-2): 155-163, 2018 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-30342005

RESUMEN

Endothelial dysfunction is a main feature of retinal neovascular diseases which are the leading cause of blindness in developed countries. Yes-associated protein (YAP) and signal transducer and activator of transcription factor 3 (STAT3) participate in angiogenesis via vascular endothelial growth factor (VEGF) signaling. Additionally, YAP can bind STAT3 in endothelial cells. In the study, dimethyloxalylglycine (DMOG) stimulated human retinal microvascular endothelial cells (HRMECs) was used as retinal endothelial hypoxia model. The proliferation of HRMECs, as well as t-YAP, p-STAT3 (Tyr705) increased, while p-YAP (Ser127), p-YAP (Ser397) decreased following hypoxia. Meanwhile, YAP and STAT3 translocated to the nucleus. YAP knockdown inhibited the proliferation, migration and tube formation of HRMECs. YAP overexpression up-regulated phosphorylation of STAT3. The YAP overexpression-induced HRMECs proliferation, migration and tube formation were reversed by S3I-201, a selective STAT3 inhibitor. YAP interacted with STAT3 to promote STAT3 nuclear translocation. Additionally, YAP and STAT3 promoted the transcription of VEGF synergistically. Finally, inhibition of YAP alleviated retinal pathological neovascularization in mouse oxygen-induced retinopathy (OIR) model. In summary, activated YAP interacted with STAT3 to promote the activation and nuclear translocation of STAT3, hence boosted the proliferation, migration and tube formation of HRMECs via VEGF signaling following hypoxia. The data will further elucidate the mechanisms of retinal neovascular diseases.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Células Endoteliales/fisiología , Endotelio Vascular/fisiología , Neovascularización Fisiológica , Fosfoproteínas/metabolismo , Vasos Retinianos/citología , Factor de Transcripción STAT3/metabolismo , Transporte Activo de Núcleo Celular , Proteínas Adaptadoras Transductoras de Señales/antagonistas & inhibidores , Animales , Proteínas de Ciclo Celular , Hipoxia de la Célula , Movimiento Celular , Núcleo Celular/metabolismo , Proliferación Celular , Células Cultivadas , Células Endoteliales/metabolismo , Endotelio Vascular/metabolismo , Humanos , Ratones Endogámicos C57BL , Microvasos/metabolismo , Microvasos/fisiología , Fosfoproteínas/antagonistas & inhibidores , Neovascularización Retiniana/patología , Factores de Transcripción , Transcripción Genética , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/fisiología , Proteínas Señalizadoras YAP
12.
Plant Biotechnol J ; 16(1): 254-263, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28574641

RESUMEN

Plant lodging resistance is an important integrative agronomic trait of grain yield and quality in crops. Although extensin proteins are tightly associated with plant cell growth and cell wall construction, little has yet been reported about their impacts on plant lodging resistance. In this study, we isolated a novel extensin-like (OsEXTL) gene in rice, and selected transgenic rice plants that expressed OsEXTL under driven with two distinct promoters. Despite different OsEXTL expression levels, two-promoter-driven OsEXTL-transgenic plants, compared to a rice cultivar and an empty vector, exhibited significantly reduced cell elongation in stem internodes, leading to relatively shorter plant heights by 7%-10%. Meanwhile, the OsEXTL-transgenic plants showed remarkably thickened secondary cell walls with higher cellulose levels in the mature plants, resulting in significantly increased detectable mechanical strength (extension and pushing forces) in the mature transgenic plants. Due to reduced plant height and increased plant mechanical strength, the OsEXTL-transgenic plants were detected with largely enhanced lodging resistances in 3 years field experiments, compared to those of the rice cultivar ZH11. In addition, despite relatively short plant heights, the OsEXTL-transgenic plants maintain normal grain yields and biomass production, owing to their increased cellulose levels and thickened cell walls. Hence, this study demonstrates a largely improved lodging resistance in the OsEXTL-transgenic rice plants, and provides insights into novel extensin functions in plant cell growth and development, cell wall network construction and wall structural remodelling.


Asunto(s)
Pared Celular/metabolismo , Oryza/metabolismo , Tallos de la Planta/metabolismo , Pared Celular/fisiología , Regulación de la Expresión Génica de las Plantas/genética , Regulación de la Expresión Génica de las Plantas/fisiología , Oryza/fisiología , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Tallos de la Planta/fisiología , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo
13.
Chemistry ; 24(1): 212-221, 2018 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-29083065

RESUMEN

In this work pH-responsive porous nanocapsules have been successfully prepared from a ternary graft copolymer, poly(glycidyl methacrylate)-g-[poly(2-cinnamoyloxyethyl methacrylate)-r-poly(ethylene glycol) methyl ether-r-poly(2-diethylaminoethyl methacrylate)] or PGMA-g-(PCEMA-r-MPEG-r-PDEAEMA). The graft copolymers were fabricated by grafting three types of polymer chains onto the backbone polymer by using click chemistry. These ternary copolymers underwent self-assembly to form vesicles in a DMF/water solvent mixture. While the MPEG chains served as the corona and stabilized the vesicles, the vesicle wall was composed of a dominant PCEMA continuous phase that was interspersed by PDEAEMA domains. After photo-cross-linking, the PDEAEMA domains were embedded in the structurally locked PCEMA wall. By decreasing the pH of the external solution, we were able to trigger the release of encapsulated pyrene due to the capsule wall becoming porous as a result of the PDEAEMA chains bearing positively charged amine groups stretching into the water. While these pH-responsive porous nanocapsules exhibited potential applications in drug delivery, detection and catalysis, the strategy reported in this contribution also represented a new paradigm for the design and preparation of other novel stimuli-responsive porous nanocapsules.

14.
Chemistry ; 23(32): 7737-7747, 2017 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-28332741

RESUMEN

A stimuli-responsive membrane exhibiting independent pH- and temperature-responsive behavior was fabricated from a blend of commercial polysulfone with a functional amphiphilic binary graft copolymer, namely, polysulfone-graft-(poly(isopropylacrylamide-co-acrylic acid)-random-poly(methyl acrylate)), denoted PSf-g-(P(NIPAAm-co-AA)-r-PMMA). Two graft copolymers with different lengths of P(NIPAAm-co-AA) side chains were designed and enriched on the membrane surface to serve as thermo- and pH-responsive on/off switches. The differences between the dual-responsive behaviors of the two kinds of polymer-blend membranes were studied by water-flux and contact-angle measurements. The PMMA side chains served to securely anchor the graft copolymers to the membrane substrate, and the blended membrane prepared from binary graft copolymer was more stable and exhibited more robust stimuli-responsive behavior than that prepared from mono-graft copolymer PSf-g-P(NIPAAm-co-AA).

15.
Phys Chem Chem Phys ; 17(29): 19457-64, 2015 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-26145165

RESUMEN

The diblock copolymer poly[2,2,2-trifluoroethyl methacrylate-r-styrene]-block-poly[(2-cinnamoyloxyethyl methacrylate)] [P(TFEMA-r-Sty)-b-PCEMA] was synthesized via atom transfer radical polymerization. The copolymer underwent self-assembly in TFEMA/CH2Cl2 to form spherical micelles. Photo-cross-linking of the PCEMA domains of these micelles yielded cross-linked nanoparticles. The cross-linked nanoparticles were subsequently cast from CH2Cl2/methanol solvent mixtures at methanol volume fractions of more than 30% to yield rough surfaces bearing small nanobumps on micron-sized aggregations that were connected together to form cross-linked nanoparticles. These surfaces were superhydrophobic with a water contact angle of 161 ± 1° and a sliding angle of 6 ± 1°. Spraying these nanoparticles onto substrates exhibiting microscale roughness, such as filter paper, by a traditional coating technique also created superhydrophobic surfaces. A thin layer of nanoscale spherical protrusions was observed on the microscale fibers of filter paper by scanning electron microscopy. The coated filter paper samples exhibited a water contact angle and a sliding angle of 153 ± 1° and 9 ± 1°, respectively.

16.
Langmuir ; 30(14): 3996-4004, 2014 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-24684287

RESUMEN

Stearic and oleic acid-coated Fe3O4 nanoparticles were dispersed in decahydronaphthalene (DN). This oil phase was dispersed in water using ternary graft copolymer poly(glycidyl methacrylate)-graft-[polystyrene-ran-(methoxy polyethylene glycol)-ran-poly(2-cinnamoyloxyethyl methacrylate)] or PGMA-g-(PS-r-MPEG-r-PCEMA) to yield capsules. The walls of these capsules were composed of PCEMA chains that were soluble in neither water nor DN, and the DN-soluble PS chains stretched into the droplet phase and the water-soluble MPEG chains extended into the aqueous phase. Structurally stable capsules were prepared by photolyzing the capsules with UV light to cross-link the PCEMA layer. Both the magnetite particles and the magnetite-containing capsules were superparamagnetic. The sizes of the capsules increased as they were loaded with more magnetite nanoparticles, reaching a maximal loading of ~0.5 mg of ligated magnetite nanoparticles per mg of copolymer. But the radii of the capsules were always <100 nm. Thus, a novel nanomaterial--superparamagnetic-oil-filled polymer nanocapsules--was prepared. The more heavily loaded capsules were readily captured by a magnet and could be redispersed via shaking. Although the cross-linked capsules survived this capturing and redispersing treatment many times, the un-cross-linked capsules ruptured after four cycles. These results suggest the potential to tailor-make capsules with tunable wall stability for magnetically controlled release applications.


Asunto(s)
Nanopartículas de Magnetita/química , Aceites/química , Polímeros/química , Estructura Molecular , Naftalenos/química , Ácido Oléico/química , Tamaño de la Partícula , Polímeros/síntesis química , Ácidos Esteáricos/química , Propiedades de Superficie
17.
Biomacromolecules ; 15(3): 968-77, 2014 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-24527876

RESUMEN

Three ternary graft copolymers bearing polystyrene (PS), poly(ethylene glycol) methyl ether (MPEG), and poly(acrylic acid) (PAA) side chains were synthesized and characterized. At pH = 7.4, these copolymers stabilized doxorubicin (DOX)-containing benzyl benzoate (BBZ) nanoemulsion droplets in water and formed a compact polymer layer to inhibit DOX release. Upon lowering the solution pH to 5.0, the AA groups dissociated less and became less soluble. Moreover, the neutralized AA groups formed presumably H-bonded complexes with the EG units, reducing the solubility of the EG units. This dual action drastically shifted the hydrophilic and hydrophobic balance of the copolymer and caused the original stabilizing polymer layer to rupture and the nanoemulsion droplets to aggregate, releasing DOX. The rate and extent of DOX release could be increased by matching the numbers of PAA and MPEG chains per graft copolymer. In addition, these nanoemulsions were not toxic and entered human carcinoma cells, releasing DOX there. Thus, these nanoemulsions have potential as drug delivery vehicles.


Asunto(s)
Doxorrubicina/administración & dosificación , Sistemas de Liberación de Medicamentos , Emulsiones/administración & dosificación , Nanopartículas/administración & dosificación , Resinas Acrílicas/química , Carcinoma/tratamiento farmacológico , Línea Celular Tumoral , Preparaciones de Acción Retardada/química , Doxorrubicina/química , Emulsiones/química , Humanos , Concentración de Iones de Hidrógeno , Nanopartículas/química , Polietilenglicoles/química , Poliestirenos/química , Solubilidad
18.
Heliyon ; 10(10): e30840, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38770313

RESUMEN

Ocular neovascularization is the leading cause of blindness in clinical settings. Pathological angiogenesis of the eye can be divided into corneal neovascularization (CoNV), retinal neovascularization (RNV, including diabetic retinopathy and retinopathy of prematurity), and choroidal neovascularization (CNV) based on the anatomical location of abnormal neovascularization. Although anti-Vascular endothelial growth factor (VEGF) agents have wide-ranging clinical applications and are an effective treatment for neovascular eye disease, many deficiencies in this treatment strategy remain. Recently, emerging evidence has demonstrated that macrophages are vital during the process of physiological and pathological angiogenesis. Monocyte-macrophage lineage is diverse and plastic, they can shift between different activation modes and have different functions. Due to the obvious regulatory effect of macrophages on inflammation and angiogenesis, macrophages have been increasingly studied in the field of ophthalmology. Here, we detail how macrophage activated and the role of different subtypes of macrophages in the pathogenesis of ocular neovascularization. The complexity of macrophages has recently taken center stage owing to their subset diversity and tightly regulated molecular and metabolic phenotypes. In this review, we reveal the functional and phenotypic characterization of macrophage subsets associated with ocular neovascularization, more in-depth research is needed to explore the specific mechanisms by which macrophages regulate angiogenesis as well as macrophage polarization. Targeted regulation of macrophage differentiation based on their phenotype and function could be an effective approach to treat and manage ocular neovascularization in the future.

19.
Heliyon ; 10(6): e27893, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38524531

RESUMEN

Globally, age-related macular degeneration (AMD) is the leading cause of irreversible visual impairment. Up to 80% of severe vision loss is caused by AMD, which is characterized by the development of choroidal neovascularization (CNV). Uncertainty exists regarding the precise pathophysiological mechanisms of CNV. It has been suggested that the interleukin (IL) IL-6/IL-6R signaling pathway is crucial in the progression of CNV. Tocilizumab (TCZ), a monoclonal antibody, binds to soluble and membrane-bound IL-6R and competitively inhibits IL-6 downstream signaling. Previous research has demonstrated that TCZ promotes several roles related to inflammation and neovascularization. However, the effects of TCZ on CNV and the underlying mechanism are still unknown. This study found that TCZ administration decreased the area and leakage of CNV lesions in the mice model of laser-induced CNV. Additionally, results demonstrated that TCZ promotes the expression of iNOS, CCL-3, CCL-5, TNF-α and inhibits the expression of Arg-1, IL-10, YM-1 and CD206. Furthermore, TCZ treatment inhibited the signal transducer and activator of transcription (STAT) STAT3/vascular endothelial growth factor (VEGF) pathway, which was activated after CNV formation. Colivelin, a STAT3 agonist, reversed the inhibitory effects of TCZ on CNV formation and macrophage polarization. In a mouse model of laser-induced CNV, our findings demonstrated that TCZ attenuated CNV formation and inhibited the leakage of CNV lesions by regulating macrophage polarization via inhibiting the STAT3/VEGF axis. TCZ is the potential therapeutic strategy for CNV.

20.
Dent Mater ; 40(2): 254-266, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37989605

RESUMEN

OBJECTIVES: In light of the constantly flowing saliva, anti-caries remineralization agents are inclined to be taken away. Owing to their limited residence time, the remineralization effect is not as desirable as expected. Hence, our study aimed to synthesize a novel peptide (DGP) with high affinity to both collagen fibrils and hydroxyapatite, and investigated its dentin remineralization efficacy in vitro and anti-caries capability in vivo. METHODS: DGP was synthesized through Fmoc solid-phase reaction. The binding ability and interaction mechanism of DGP to demineralized dentin were investigated. Dentin specimens were demineralized, then treated with DGP and deionized water respectively. The specimens were incubated in artificial saliva and in-vitro remineralization effectiveness was analyzed after 14 days. The rat caries model was established to further scrutinize the in-vivo efficacy of caries prevention. RESULTS: DGP possesses an enhanced adhesion force of 12.29 ± 1.12 nN to demineralized dentin. The favorable adsorption capacity is ascribed to the stable hydrogen bonds between S2P-101 and ASP-100 of DGP and GLY33 and PRO-16 of collagen fibers. Abundant mineral deposits and remarkable tubule occlusion were observed in the DGP group. DGP-treated dentin obtained notable microhardness recovery and higher mineral content after a 14-day remineralization regimen. DGP also demonstrated potent caries prevention in vivo, with substantially fewer carious lesions and significantly lower Keyes scoring. SIGNIFICANCE: DGP proves to possess a high affinity to demineralized dentin regardless of saliva flowing, thus enhancing remineralization potency significantly in vitro and in vivo, potential for dental caries prevention and combatting initial dentin caries clinically.


Asunto(s)
Caries Dental , Humanos , Caries Dental/tratamiento farmacológico , Caries Dental/patología , Cariostáticos , Dentina/química , Minerales , Colágeno/química , Remineralización Dental
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