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1.
Nanotechnology ; 35(40)2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-38991514

RESUMEN

The widespread use of antibiotics often increases bacterial resistance. Herein, we reported a silver peroxide-incorporated carbon dots (defined as Ag2O2-CDs) with high photothermal conversion efficiency viain situoxidation process. The prepared Ag2O2-CDs exhibited ultra-small size of 2.0 nm and hybrid phase structure. Meanwhile, the Ag2O2-CDs were of a similar optical performance comparing with traditional carbon dots (CDs). Importantly, the incorporation of Ag2O2into CDs significantly enhanced photothermal conversion efficiency from 3.8% to 28.5%. By combining silver ion toxicity and photothermal ablation, the Ag2O2-CDs were capable of destroying gram-positive and gram-negative bacterium effectively. These findings demonstrated that the Ag2O2-CDs could be served as a potential antibacterial agent for clinical applications.


Asunto(s)
Antibacterianos , Carbono , Puntos Cuánticos , Compuestos de Plata , Carbono/química , Puntos Cuánticos/química , Antibacterianos/farmacología , Antibacterianos/química , Compuestos de Plata/química , Compuestos de Plata/farmacología , Óxidos/química , Óxidos/farmacología , Peróxidos/química , Peróxidos/farmacología , Plata/química , Plata/farmacología , Pruebas de Sensibilidad Microbiana , Escherichia coli/efectos de los fármacos
2.
Nanotechnology ; 34(5)2022 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-36195012

RESUMEN

Photothermal therapy (PTT) is a promising treatment that efficiently suppresses local cancer, but fails to induce a robust antitumor immune response against tumor metastasis and recurrence. In this study, a NIR responsive nano-immunostimulant (Mn/A-HP NI) is fabricated by entrapping manganese and azo-initiator (AIPH) into hyaluronic acid-based polypyrrole nanoparticle. The as-prepared Mn/A-HP NIs with a high photothermal conversion efficiencey of 20.17% dramatically induced the imunogenic cell death of tumor cells and triggered the release ATP and HMGB1. Meanwhile, the hyperthermia induced AIPH decomposition to produce alkyl radicals which further destroyed cancer cells. Furthermore, the Mn/A-HP NIs were capable of promoting the maturation and antigen cross-presentation ability of dendritic cells. Consequently, the multifunctional Mn/A-HP NIs provided a combined treatment via integrating PTT/chemo-dynamic therapy and immune activation for tumor therapy.


Asunto(s)
Hipertermia Inducida , Nanopartículas , Polímeros/química , Terapia Fototérmica , Pirroles/farmacología , Nanopartículas/química , Línea Celular Tumoral , Fototerapia
3.
J Nanobiotechnology ; 20(1): 297, 2022 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-35733214

RESUMEN

BACKGROUND: Phototherapy-triggered immunogenic cell death (ICD) rarely elicits a robust antitumour immune response, partially due to low antigen exposure and inefficient antigen presentation. To address these issues, we developed novel methylene blue-loaded ovalbumin/polypyrrole nanoparticles (MB@OVA/PPY NPs) via oxidative polymerization and π-π stacking interactions. RESULTS: The as-prepared MB@OVA/PPY NPs with outstanding photothermal conversion efficiency (38%) and photodynamic properties were readily internalized into the cytoplasm and accumulated in the lysosomes and mitochondria. Upon 808 nm and 660 nm laser irradiation, the MB@OVA/PPY NPs not only ablated tumour cells by inducing local hyperthermia but also damaged residual tumour cells by generating a large amount of reactive oxygen species (ROS), finally triggering the release of many damage-associated molecular patterns (DAMPs). Moreover, the MB@OVA/PPY NPs synergized with DAMPs to promote the maturation and improve the antigen presentation ability of DCs in vitro and in vivo. CONCLUSIONS: This work reported a PPY NPs-based nanoplatform to encapsulate the therepeutic proteins and absorb the functional molecules for combination therapy of tumours. The results demonstrated that the prepared MB@OVA/PPY NPs could be used as effective nanotherapeutic agents to eliminate solid tumours and trigger a powerful antitumour immune response.


Asunto(s)
Nanopartículas , Neoplasias , Humanos , Azul de Metileno/farmacología , Nanopartículas/uso terapéutico , Neoplasias/terapia , Ovalbúmina , Fototerapia/métodos , Polímeros/farmacología , Pirroles/farmacología
4.
Nanotechnology ; 32(39)2021 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-34161927

RESUMEN

Ferroptosis as an iron-dependent lipid peroxidation process causes sevely oxidative damage of cell, but lack of highly efficient and recycable antioxidant agents. To this end, cerium doped carbon dots (Ce-doped CDs) with radical scavenging activity were synthesized using a simple microwave-assisted hydrothermal carbonization. The resultant Ce-doped CDs exhibited an ultra-small size of only approximately 2.6 nm, excellent dispersion in water as well as optical performance. Taking advantage of inherent ultra-small size, Ce-doped CDs were endowed with high Ce3+/Ce4+ratio, which significantly enhanced their radical scavenging activity. Meanwhile, the Ce-doped CDs with superior biocompatibility could enter cells quickly and then localized in the cytoplasm. As we expected, the Ce-doped CDs strongly protected cells from oxidative damage of erastin-mediated ferroptosis. These findings suggest that the as-prepared Ce-doped CDs have the potential to be antioxidant drugs against for ferroptosis-induced oxidative damage.


Asunto(s)
Cerio , Ferroptosis/efectos de los fármacos , Depuradores de Radicales Libres , Estrés Oxidativo/efectos de los fármacos , Puntos Cuánticos/química , Animales , Carbono/química , Carbono/farmacología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Cerio/química , Cerio/farmacología , Depuradores de Radicales Libres/química , Depuradores de Radicales Libres/farmacología , Humanos , Ratones , Células 3T3 NIH
5.
J Nanobiotechnology ; 19(1): 142, 2021 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-34001148

RESUMEN

BACKGROUND: Therapeutic tumor vaccine (TTV) that induces tumor-specific immunity has enormous potentials in tumor treatment, but high heterogeneity and poor immunogenicity of tumor seriously impair its clinical efficacy. Herein, a novel NIR responsive tumor vaccine in situ (HA-PDA@IQ/DOX HG) was prepared by integrating hyaluronic acid functionalized polydopamine nanoparticles (HA-PDA NPs) with immune adjuvants (Imiquimod, IQ) and doxorubicin (DOX) into thermal-sensitive hydrogel. RESULTS: HA-PDA@IQ NPs with high photothermal conversion efficiency (41.2%) and T1-relaxation efficiency were using HA as stabilizer by the one-pot oxidative polymerization. Then, HA-PDA@IQ loaded DOX via π-π stacking and mixed with thermal-sensitive hydrogel to form the HA-PDA@IQ/DOX HG. The hydrogel-confined delivery mode endowed HA-PDA@IQ/DOX NPs with multiple photothermal ablation performance once injection upon NIR irradiation due to the prolonged retention in tumor site. More importantly, this mode enabled HA-PDA@IQ/DOX NPs to promote the DC maturation, memory T cells in lymphatic node as well as cytotoxic T lymphocytes in spleen. CONCLUSION: Taken together, the HA-PDA@IQ/DOX HG could be served as a theranostic tumor vaccine for complete photothermal ablation to trigger robust antitumor immune responses.


Asunto(s)
Vacunas contra el Cáncer/uso terapéutico , Quimioterapia/métodos , Inmunidad/efectos de los fármacos , Inmunidad/efectos de la radiación , Terapia Fototérmica/métodos , Doxorrubicina/administración & dosificación , Ácido Hialurónico , Hidrogeles , Indoles/química , Nanopartículas/administración & dosificación , Neoplasias/tratamiento farmacológico , Neoplasias/radioterapia , Polímeros/administración & dosificación , Polímeros/química
6.
J Cell Mol Med ; 24(2): 1969-1979, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31851779

RESUMEN

Protein arginine methyltransferase 5 (PRMT5) has been implicated in the development and progression of human cancers. However, few studies reveal its role in epithelial-mesenchymal transition (EMT) of pancreatic cancer cells. In this study, we find that PRMT5 is up-regulated in pancreatic cancer, and promotes proliferation, migration and invasion in pancreatic cancer cells, and promotes tumorigenesis. Silencing PRMT5 induces epithelial marker E-cadherin expression and down-regulates expression of mesenchymal markers including Vimentin, collagen I and ß-catenin in PaTu8988 and SW1990 cells, whereas ectopic PRMT5 re-expression partially reverses these changes, indicating that PRMT5 promotes EMT in pancreatic cancer. More importantly, we find that PRMT5 knockdown decreases the phosphorylation level of EGFR at Y1068 and Y1172 and its downstream p-AKT and p-GSK3ß, and then results in down-regulation of ß-catenin. Expectedly, ectopic PRMT5 re-expression also reverses the above changes. It is suggested that PRMT5 promotes EMT probably via EGFR/AKT/ß-catenin pathway. Taken together, our study demonstrates that PRMT5 plays oncogenic roles in the growth of pancreatic cancer cell and provides a potential candidate for pancreatic cancer treatment.


Asunto(s)
Transición Epitelial-Mesenquimal , Receptores ErbB/metabolismo , Neoplasias Pancreáticas/enzimología , Neoplasias Pancreáticas/patología , Proteína-Arginina N-Metiltransferasas/metabolismo , Transducción de Señal , beta Catenina/metabolismo , Animales , Carcinogénesis/genética , Carcinogénesis/patología , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Ratones Endogámicos BALB C , Ratones Desnudos , Invasividad Neoplásica , Neoplasias Pancreáticas/genética , Proteína-Arginina N-Metiltransferasas/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Neoplasias Pancreáticas
7.
Adv Funct Mater ; 30(14)2020 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-32440263

RESUMEN

Breast cancer brain metastases (BCBMs) represent a major cause of morbidity and mortality among patients with breast cancer. Chemotherapy, which is widely used to treat tumors outside of the brain, is often ineffective on BCBMs due to its inability to efficiently cross the blood-brain barrier (BBB). Although the BBB is partially disrupted in tumor lesions, it remains intact enough to prevent most therapeutics from entering the brain. Here, we report a nanotechnology approach that can overcome the BBB through synthesis of lexiscan-loaded, AMD3100-conjugated, shrinkable NPs, or LANPs. LANPs respond to neutrophil elastase-enriched tumor microenvironment by shrinking in size and disrupt the BBB in tumors through lexiscan-mediated modulation. LANPs recognize tumor cells through the interaction between AMD3100 and CXCR4, which are expressed in metastatic tumor cells. We demonstrate that the integration of tumor responsiveness, tumor targeting, and BBB penetration enables LANPs to penetrate metastatic lesions in the brain with high efficiency, and, when doxorubicin was encapsulated, LANPs effectively inhibited tumor growth and prolonged the survival of tumor-bearing mice. Due to their high efficiency in penetrating the BBB for BCBMs treatment, LANPs have the potential to be translated into clinical applications for improved treatment of patients with BCBMs.

8.
Nanotechnology ; 31(16): 165101, 2020 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-31766034

RESUMEN

The antioxidant activity of ceria nanoparticles is tightly regulated by size distribution and heteroatom doping. Inspired by this rule, cerium and praseodymium codoped carbon quantum dots (Ce/Pr-CQDs) were synthesized through the one-pot hydrothermal carbonization method. Taking intrinsic advantage of CQDs, the resultant Ce/Pr-CQDs exhibited uniform and ultra-small morphology with an average size of 2.8 nm, which led to an increased proportion of Ce3+. In addition, the doping of Pr into Ce-CQDs improved the redox properties. As we expected, the Ce/Pr-CQDs possessed enhanced hydroxyl radical scavenging properties compared with the cerium-doped carbon quantum dots (Ce-CQDs). Furthermore, Ce/Pr-CQDs with favorable biocompatibility and negligible cytotoxicity are readily internalized into cytoplasm, decreasing the level of reactive oxygen species (ROS). Taken together, the resultant Ce/Pr-CQDs displayed great potential for applications relating to oxidative-stress-associated disease.


Asunto(s)
Antioxidantes/farmacología , Carbono/química , Cerio/química , Depuradores de Radicales Libres/farmacología , Radical Hidroxilo/química , Praseodimio/química , Puntos Cuánticos/química , Animales , Muerte Celular/efectos de los fármacos , Línea Celular , Ratones , Oxidación-Reducción , Puntos Cuánticos/ultraestructura , Difracción de Rayos X
9.
Nanotechnology ; 31(25): 255601, 2020 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-32126545

RESUMEN

To enhance the therapeutic efficiency and reduce side effects from drug delivery and chemotherapy, image-guided nanoscale systems have attracted tremendous attention in recent decades. In this study, we developed a novel method to fabricate a colchicine/gadolinium-loaded tubulin self-assembly nanocarrier (Col-Gd@Tub NC) for the image-guided chemotherapy of glioma. The Col-Gd@Tub NCs were spontaneously formed via tubulin self-assembly and were subsequently functionalized by colchicine and gadolinium elements. These resultant Col-Gd@Tub NCs with a diameter of 45 nm exhibited uniform particle size distribution and favorable stability without any leakage of gadolinium in water. Meanwhile, the introduction of gadolinium endowed Col-Gd@Tub NCs with high T 1-weighted MRI performance in vitro. After tail vein injection, Col-Gd@Tub NCs exhibited excellent MRI contrast capability and relatively long circulation time (∼12 h) and were finally cleared out from the bladder. More significantly, the binding colchicine still exerted an anti-tumor effect after the Col-Gd@Tub NCs were taken up by the tumor cells. These results show that the Col-Gd@Tub NCs may be served as a versatile nanoscale platform for the integration of biomedical imaging probes and therapeutic molecules for tumor therapy.


Asunto(s)
Antineoplásicos/administración & dosificación , Neoplasias Encefálicas/tratamiento farmacológico , Colchicina/administración & dosificación , Gadolinio/química , Glioma/tratamiento farmacológico , Tubulina (Proteína)/química , Animales , Antineoplásicos/química , Antineoplásicos/farmacología , Neoplasias Encefálicas/diagnóstico por imagen , Línea Celular Tumoral , Colchicina/química , Colchicina/farmacología , Dispersión Dinámica de Luz , Femenino , Glioma/diagnóstico por imagen , Células HEK293 , Humanos , Imagen por Resonancia Magnética , Nanopartículas del Metal , Ratones , Microscopía Electrónica de Transmisión , Tamaño de la Partícula , Ensayos Antitumor por Modelo de Xenoinjerto
11.
Nanotechnology ; 30(32): 325101, 2019 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-30909174

RESUMEN

Excessive reactive oxygen species (ROS) can lead to irreversible damage to the human body in vivo, therefore it is highly desirable to exploit an efficient antioxidant. Recently, cerium oxide nanoparticles have attracted extensive attention in the field of biomedicine due to their excellent antioxidant properties. In this study, cerium-doped carbon quantum dots (Ce-doped CQDs) with hydroxyl radical scavenging capacity were synthesized for first time by one-step hydrothermal carbonization method. The resultant Ce-doped CQDs with the average particle size of 2.5 nm possessed the properties of good water solubility, colloid stability, and strong fluorescence, which are similar to traditional CQDs. Meanwhile, the Ce-doped CQDs had good biocompatibility and negligible cytotoxicity. Taking advantage of inherent ultra-small size, the Ce-doped CQDs exhibited a high Ce3+/Ce4+ ratio at the surface of particles. The radical scavenging capability of the Ce-doped CQDs was proved by a simple photometric system in vitro, which provided direct evidence for its antioxidant potency. Furthermore, the Ce-doped CQDs had a high ability to protect cells from hydrogen peroxide-induced damage by scavenging hydroxyl radicals. These results suggest that Ce-doped CQDs as a new ROS scavenger may provide potential prospects for the treatment of oxidative stress-related diseases.

12.
Adv Exp Med Biol ; 1097: 181-189, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30315545

RESUMEN

Coronary artery disease (CAD) is the leading cause of mortality and morbidity worldwide. Clinically, CAD can be potentially managed through surgical artery bypass. However, due to the highly invasive nature, surgical intervention has been gradually replaced by percutaneous transluminal coronary angioplasty and recently by percutaneous coronary revascularization using metallic stents. However, the permanent presence of metallic scaffolds inevitably impairs arterial physiology and may induce a variety of adverse effects, such as inflammation, restenosis, thrombosis, and neoatherosclerosis. To address these limitations, revascularization using bioresorbable vascular scaffolds (BVSs) has emerged as the most promising approach. After angioplasty, BVSs provide temporarily mechanical support and are completely resorbed over defined time. This transient nature allows favorable arterial remodeling and avoids thrombosis and in-stent restenosis. However, the theoretical advantages of BVSs have yet to be demonstrated. In this chapter, we first review the evolution of nonsurgical vascular intervention approaches over the past few decades. Next, we discuss the current status of BVS development and propose potential approaches to addressing the limitations associated with the current BVSs.


Asunto(s)
Implantes Absorbibles , Angioplastia , Enfermedad de la Arteria Coronaria/cirugía , Andamios del Tejido , Materiales Biocompatibles , Reestenosis Coronaria/prevención & control , Humanos , Intervención Coronaria Percutánea , Diseño de Prótesis , Stents , Resultado del Tratamiento
13.
Br J Cancer ; 116(1): 91-99, 2017 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-27898661

RESUMEN

BACKGROUND: Methyl-CpG-binding domain 3 (MBD3) is an aberrant expression in human malignancies. However, the role of MBD3 in pancreatic cancer progression remains to be clarified. In this study, we investigated the effects of MBD3 on the epithelial-mesenchymal transition (EMT), and the underlying mechanism in pancreatic cancer cells. METHODS: The abilities of migration and invasion were examined by transwell and BD Matrigel invasion assays. EMT and TGF-ß/Smad signalling were evaluated. RESULTS: First, we find that MBD3 expression is lower in pancreatic cancer tissues than that in non-tumour tissues, and patients with lower MBD3 levels survive significantly less than those with higher levels. Subsequently, we find that MBD3 knockdown promotes the abilities of migration and invasion, while MBD3 overexpression inhibits the above abilities. Also, MBD3 knockdown remarkably increases mesenchymal markers expression of Vimentin, α-SMA, Snail, N-cadherin, ß-catenin, and downregulates epithelial markers expression of E-cadherin. On the contrary, MBD3 overexpression results in the opposite effects. Further evidence reveals that MBD3 knockdown up-regulates expression of TGF-ß, and then activates p-Smad2 and p-Smad3, while MBD3 overexpression results in downregulation of TGF-ß, p-Smad2, and p-Smad3. CONCLUSIONS: MBD3 inhibits EMT in pancreatic cancer cells probably via TGF-ß/Smad signalling, and may be a new candidate target for diagnostics and prognosis of pancreatic cancer.


Asunto(s)
Adenocarcinoma/patología , Proteínas de Unión al ADN/fisiología , Transición Epitelial-Mesenquimal/genética , Neoplasias Pancreáticas/patología , Proteínas Smad/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Adenocarcinoma/diagnóstico , Adenocarcinoma/genética , Biomarcadores de Tumor/genética , Línea Celular Tumoral , Células HEK293 , Humanos , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/genética , Pronóstico , Transducción de Señal/genética
14.
Cell Biol Toxicol ; 33(6): 527-537, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28185110

RESUMEN

Although methylguanine-DNA-methyltransferase (MGMT) plays an important role in resistance to temozolomide (TMZ) in glioma, 40% of gliomas with MGMT inactivation are still resistant to TMZ. The underlying mechanism is not clear. Here, we report that forkhead box M1 (FoxM1) transcriptionally activates the expression of DNA repair gene replication factor C5 (RFC5) to promote TMZ resistance in glioma cells independent of MGMT activation. We showed that RFC5 expression is positively correlated with FoxM1 expression in human glioma cells and FoxM1 is able to transcriptionally activate RFC expression by interaction with the RFC5 promoter. Furthermore, knockdown of FoxM1 or RFC5 partially re-sensitizes glioma cells to TMZ. Consistently, thiostrepton, a FoxM1 inhibitor, in combination with TMZ significantly inhibits proliferation and promotes apoptosis in glioma cells. Taken together, these findings suggest that the FoxM1-RFC5 axis may mediate TMZ resistance and thiostrepton may serve as a potential therapeutic agent against TMZ resistance in glioma cells.


Asunto(s)
Dacarbazina/análogos & derivados , Proteína Forkhead Box M1/genética , Glioma/tratamiento farmacológico , Proteína de Replicación C/genética , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Línea Celular Tumoral , Reparación del ADN , Dacarbazina/farmacología , Resistencia a Antineoplásicos , Proteína Forkhead Box M1/metabolismo , Glioma/genética , Glioma/metabolismo , Humanos , O(6)-Metilguanina-ADN Metiltransferasa/metabolismo , Regiones Promotoras Genéticas , Proteína de Replicación C/biosíntesis , Proteína de Replicación C/metabolismo , Temozolomida , Tioestreptona/farmacología
15.
Exp Cell Res ; 340(1): 62-70, 2016 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-26708617

RESUMEN

Previous studies suggest that early growth response gene-1 (Egr-1) plays an important role in hypoxia-induced drug-resistance. However, the mechanism still remains to be clarified. Herein, we investigated the role of Egr-1 in hypoxia-induced autophagy and its resulted hypoxia-driven chemo-resistance in Hepatocellular Carcinoma (HCC) cells. Our data demonstrated that Egr-1 was overexpressed in HCC tissues and cells and conferred them drug resistance under hypoxia. Mechanistically, Egr-1 transcriptionally regulated hypoxia-induced autophagy by binding to LC3 promoter in HCC cells, which resulted in resistance of HCC cells to chemotherapeutic agents; while dominant negative Egr-1 could inhibit autophagy level, and thus enhanced the sensitivity of HCC cells to chemotherapeutic agents, indicating that hypoxia-induced Egr-1 expression enhanced drug resistance of HCC cells likely through autophagy. Accordingly, it is suggested that a mechanism of hypoxia/Egr-1/autophagy axis might be involved in drug resistance in HCC.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Autofagia , Carcinoma Hepatocelular/tratamiento farmacológico , Resistencia a Antineoplásicos , Proteína 1 de la Respuesta de Crecimiento Precoz/metabolismo , Neoplasias Hepáticas/tratamiento farmacológico , Autofagia/efectos de los fármacos , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Ciclo Celular/efectos de los fármacos , Hipoxia de la Célula/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Resistencia a Antineoplásicos/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Proteína 1 de la Respuesta de Crecimiento Precoz/genética , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Células Hep G2 , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Relación Estructura-Actividad , Células Tumorales Cultivadas
16.
Cell Physiol Biochem ; 38(2): 449-60, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26828432

RESUMEN

BACKGROUND/AIMS: Age-associated and stress-induced involution of the thymus is accompanied by reduced numbers of thymic epithelial cells (TECs) and severe reduction in peripheral T cell repertoire specificities. These events seriously affect immune function, but the mechanisms involved are unclear. Our preliminary findings showed that doxycycline (Dox) could drive the proliferation of a TEC line (MTEC1 cells) partially via the MAPK signaling pathway. Dox can also up-regulate IL-6 and GM-CSF expression via the NF-κB and MAPK/ERK pathways. Herein, we investigate the effects and mechanisms used by Dox that protect against mitomycin C (MMC)-induced MTEC1 cell apoptosis. METHODS: MTEC1 cells were treated with Dox, MMC, and Dox plus MMC for different amounts of time. The expression of Trx2, NF-κB, Bcl-2, and Bax proteins were then detected by western blotting. RESULTS: Our findings show that Dox protects MTEC1 cells from MMC-induced apoptosis. Dox up-regulated the expression of Trx2 and promoted NF-κB phosphorylation. Meanwhile, Dox also increased the expression of Bcl-2, partially reduced the expression of Bax, and normalized the ratio of Bcl-2 to Bax. CONCLUSION: Dox exerts an anti-apoptosis function via the NF-κB-Bcl-2/Bax and Trx2-ASK1/JNK pathways in vitro. Therefore, Dox may represent a drug that could be used to attenuate thymic senescence, rescue thymic function, and promote T cell reconstitution.


Asunto(s)
Antibacterianos/farmacología , Apoptosis/efectos de los fármacos , Doxiciclina/farmacología , Mitomicina/farmacología , Sustancias Protectoras/farmacología , Timo/citología , Timo/efectos de los fármacos , Animales , Antibióticos Antineoplásicos/farmacología , Línea Celular , Ratones , FN-kappa B/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Transducción de Señal/efectos de los fármacos , Tiorredoxinas/metabolismo , Proteína X Asociada a bcl-2/metabolismo
17.
Cell Physiol Biochem ; 40(1-2): 277-286, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27855406

RESUMEN

BACKGROUND/AIMS: This study was to investigate the influence of scoparone on pancreatic fibrosis in vitro and in vivo. METHODS: Pancreatic stellate cells (PSCs) were isolated from pancreas tissue blocks, and cultured for 3-5 generations for the experiment. PSCs were treated with scoparone in different doses as experimental groups, salvianolic acid B as a positive control and PBS as a blank group. We measured the effects of scoparone on cellular proliferation, oxidative stress, epithelial-mesenchymal transition (EMT), and pancreatic fibrosis. Cellular oxidative stress was detected by using commercially available kits. The impact of scoparone on EMT and fibrosis was detected through immunofluorescence or western blotting. RESULTS: Compared with the control group, scoparone significantly inhibited stellate cell proliferation, and reduced MDA, the expression of mesenchymal makers, and increased the levels of SOD and the expression of E-cadherin (P < 0.05). Western blot analysis showed that scoparone downregulated the expression of TGF-ß and p-smad2/3, and upregultated the expression of smad7 (P < 0.05). CONCLUSION: Scoparone can reduce the levels of oxidative stress, repress pancreatic stellate cells activation, and alleviate fibrosis by regulating TGF-ß/Smad pathway.


Asunto(s)
Cumarinas/farmacología , Páncreas/metabolismo , Páncreas/patología , Sustancias Protectoras/farmacología , Transducción de Señal/efectos de los fármacos , Proteínas Smad/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Animales , Biomarcadores/metabolismo , Proliferación Celular/efectos de los fármacos , Separación Celular , Células Cultivadas , Cumarinas/uso terapéutico , Transición Epitelial-Mesenquimal/efectos de los fármacos , Fibrosis , Masculino , Malondialdehído/metabolismo , Estrés Oxidativo/efectos de los fármacos , Páncreas/efectos de los fármacos , Células Estrelladas Pancreáticas/efectos de los fármacos , Células Estrelladas Pancreáticas/metabolismo , Células Estrelladas Pancreáticas/patología , Pancreatitis Crónica/tratamiento farmacológico , Pancreatitis Crónica/patología , Sustancias Protectoras/uso terapéutico , Ratas Sprague-Dawley , Superóxido Dismutasa/metabolismo
18.
Reprod Fertil Dev ; 27(2): 419-26, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24384042

RESUMEN

Decreasing oocyte competence with maternal aging is a major factor in mammalian infertility. One of the factors contributing to this infertility is changes to chromatin modifications, such as histone acetylation in old MII stage oocytes. Recent studies indicate that changes in histone acetylation at MII arise at the germinal vesicle (GV) stage. We hypothesised that histone methylation could also change in old GV oocytes. To test this hypothesis, we examined mono-, di- and trimethylation of histone H3 lysine 4 (H3K4 me1, me2 and me3, respectively) in young and older oocytes from 6-8- and 42-44-week-old mice, respectively. We found that H3K4 me2 and me3 decreased in older compared with young GV oocytes (100% vs. 81% and 100% vs. 87%, respectively; P<0.05). H3K4 me2 later increased in older MII oocytes (21% vs. 56%; P<0.05). We also examined the expression of genes encoding the H3K4 demethylases lysine (K)-specific demethylase 1A (Kdm1a) and retinol binding protein 2 (Rbp2). Expression of Kdm1a increased at both the mRNA and protein levels in older GV oocytes, but decreased in older MII oocytes (P<0.05), and was negatively correlated with H3K4 me2 levels. Conversely, expression of Rbp2 mRNA and protein decreased in older GV oocytes (P<0.05), and this was not correlated with H3K4 me3 levels. Finally, we showed that inhibition of Kdm1a of older oocytes at the GV stage restored levels of H3K4 me2 at the MII stage to those seen in 'young' oocytes (41% vs. 38%; P>0.05). These results suggest that changes in expression of H3K4 me2 and Kdm1a in older GV oocytes may represent a molecular mechanism underlying human infertility caused by aging.


Asunto(s)
Envejecimiento/fisiología , Núcleo Celular/metabolismo , Metilación de ADN/fisiología , Histonas/metabolismo , Infertilidad Femenina/etiología , Oocitos/metabolismo , Animales , Cartilla de ADN/genética , Femenino , Histona Demetilasas/metabolismo , Inmunohistoquímica , Técnicas de Maduración In Vitro de los Oocitos/métodos , Ratones , Microscopía Fluorescente , Reacción en Cadena en Tiempo Real de la Polimerasa , Proteínas Celulares de Unión al Retinol/metabolismo , Tranilcipromina
19.
Nanotechnology ; 25(31): 315702, 2014 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-25036467

RESUMEN

Carbon quantum dots (CDs) are promising nanomaterials in biomedical, photocatalytical and photoelectronic applications. However, determining how to explore an ideal precursor for a renewable carbon resource is still an interesting challenge. Here, for the first time, we report that renewable wastes of bagasse as a new precursor were prepared for fluorescent CDs by a hydrothermal carbonization (HTC) process. The characterization results show that such bagasse-derived CDs are monodispersed, contain quasi spherical particles with a diameter of about 1.8 nm and exhibit favorable photoluminescence properties, super-high photostability and good dispersibility in water. Most importantly, bagasse-derived CDs have good biocompatibility and can be easily and quickly internalized by living cancer cells; they can also be used for multicolour biolabeling and bioimaging in cancer cells. It is suggested that bagasse-derived CDs might have potential applications in biomedical and photoelectronic fields.


Asunto(s)
Carbono/química , Celulosa/química , Colorantes Fluorescentes , Puntos Cuánticos/química , Línea Celular Tumoral , Humanos , Microscopía Fluorescente , Neoplasias/patología , Puntos Cuánticos/toxicidad , Puntos Cuánticos/ultraestructura
20.
Huan Jing Ke Xue ; 45(7): 4152-4163, 2024 Jul 08.
Artículo en Zh | MEDLINE | ID: mdl-39022962

RESUMEN

Revealing the spatiotemporal coupling relationship between urbanization and ecosystem services can help to clarify regional development differences, optimize the implementation path of urbanization, and improve the quality of ecosystem services. Taking southeastern Fujian, a region with a good ecological foundation and strong urbanization potential, as a case study, the levels of multidimensional urbanization systems and typical ecosystem services of this region in the years 2000, 2010, and 2020 were quantified using the index comprehensive evaluation method and the InVEST model. The Pearson correlation coefficient and the coupling coordination degree model were used to analyze the spatiotemporal coupling relationship between urbanization and ecosystem services, and suggestions for improving regional coordinated development were proposed. The results showed that: ① The comprehensive urbanization level in southeastern Fujian increased continuously, with an average annual growth rate of 7.3%, of which social urbanization was the fastest, followed by economic urbanization and population urbanization, and spatial urbanization was relatively backward. Ecosystem services tended to decline, especially food and water provision services, which decreased by 61.9% and 46.9%, respectively. The spatial distribution showed a mismatch pattern of "high urbanization level and weak ecosystem services" in the southeast coastal area and "low urbanization level and strong ecosystem services" in the northwest inland area. ② The correlation between urbanization and ecosystem services was mainly negative. The negative effect of economic and social urbanization on ecosystem services was weaker than that of population and spatial urbanization, with a clear weakening tendency. As population and spatial urbanization slowed down sharply and economic and social urbanization accelerated, the driving force of urbanization development gradually shifted from "quantitative increase" to "qualitative improvement." Thus, the decline of ecosystem services was alleviated. ③ Comprehensive urbanization and various ecosystem services experienced three stages of "imbalance-transition-reconciliation," with an average increase of 60.5% to 120.6% in the coupling coordination degree. However, highly coordinated regions remained scarce, indicating that there is still significant room for improvement. The relative relationship between urbanization and ecosystem services evolved from urbanization lag to ecosystem services lag. The fluctuation problem of backward coupling coordination level caused by excessive urbanization had initially appeared in the southeastern coastal area. Therefore, in future construction, southeastern Fujian should improve economic quality and social benefits; strengthen the overall management, protection, and restoration of ecological space; and enhance the order and stability of the coordinated development of urbanization and ecosystem services.

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