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1.
Langmuir ; 40(2): 1348-1357, 2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38176059

RESUMEN

Developing a semiconductor-based heterostructure photoanode is crucial in improving the photoelectrocatalytic (PEC) efficiency for degrading refractory organic pollutants. Nevertheless, the PEC performance of the photoanodes is usually restricted by electron/hole pair recombination, oxygen evolution, and slow electron transfer. Herein, a novel CoO@BiVO4 nanowire array film (Ti/CoO@BiVO4) with n-type semiconductor characteristics was prepared via a straightforward hydrothermal method. The optimized Ti/CoO@BiVO4 electrode exhibited excellent PEC decolorization efficiency of active brilliant blue KN-R (∼92.8%) and long-term stability, outperforming recent reports. The insight reason for enhancing the PEC degradation efficiency of the Ti/CoO@BiVO4 electrodes can be attributed to the large electrochemical active area, low charge transfer resistance, and negative flat band potential. The formation of a type-II heterostructure was investigated between CoO and BiVO4 further to promote the generation and separation efficiency of electron/hole pairs, indicating that the optimized Ti/CoO@BiVO4 electrode has the potential for the water PEC degradation ability and superior service life.

2.
EMBO J ; 38(18): e100811, 2019 09 16.
Artículo en Inglés | MEDLINE | ID: mdl-31436334

RESUMEN

The retina is a specialized neural tissue that senses light and initiates image processing. Although the functional organization of specific retina cells has been well studied, the molecular profile of many cell types remains unclear in humans. To comprehensively profile the human retina, we performed single-cell RNA sequencing on 20,009 cells from three donors and compiled a reference transcriptome atlas. Using unsupervised clustering analysis, we identified 18 transcriptionally distinct cell populations representing all known neural retinal cells: rod photoreceptors, cone photoreceptors, Müller glia, bipolar cells, amacrine cells, retinal ganglion cells, horizontal cells, astrocytes, and microglia. Our data captured molecular profiles for healthy and putative early degenerating rod photoreceptors, and revealed the loss of MALAT1 expression with longer post-mortem time, which potentially suggested a novel role of MALAT1 in rod photoreceptor degeneration. We have demonstrated the use of this retina transcriptome atlas to benchmark pluripotent stem cell-derived cone photoreceptors and an adult Müller glia cell line. This work provides an important reference with unprecedented insights into the transcriptional landscape of human retinal cells, which is fundamental to understanding retinal biology and disease.


Asunto(s)
Degeneración Nerviosa/genética , ARN Largo no Codificante/genética , Retina/química , Análisis de la Célula Individual/métodos , Transcriptoma , Autopsia , Análisis por Conglomerados , Bases de Datos Genéticas , Perfilación de la Expresión Génica/métodos , Regulación de la Expresión Génica , Humanos , Especificidad de Órganos , Células Fotorreceptoras Retinianas Bastones/química , Análisis de Secuencia de ARN , Aprendizaje Automático no Supervisado
3.
Small ; 19(49): e2206688, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37606911

RESUMEN

Non-small cell lung cancer (NSCLC) is the most common pathological type of lung cancer , accounting for approximately 85% of lung cancers. For more than 40 years, platinum (Pt)-based drugs are still one of the most widely used anticancer drugs even in the era of precision medicine and immunotherapy. However, the clinical limitations of Pt-based drugs, such as serious side effects and drug resistance, have not been well solved. This study constructs a new albumin-encapsulated Pt(IV) nanodrug (HSA@Pt(IV)) based on the Pt(IV) drug and nanodelivery system. The characterization of nanodrug and biological experiments demonstrate its excellent drug delivery and antitumor effects. The multi-omics analysis of the transcriptome and the ionome reveals that nanodrug can activate ferroptosis by affecting intracellular iron homeostasis in NSCLC. This study provides experimental evidence to suggest the potential of HSA@Pt(IV) as a nanodrug with clinical application.


Asunto(s)
Antineoplásicos , Carcinoma de Pulmón de Células no Pequeñas , Ferroptosis , Neoplasias Pulmonares , Nanopartículas , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/metabolismo , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Albúminas , Hierro/farmacología , Línea Celular Tumoral
4.
Pharmacol Res ; 187: 106617, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36535572

RESUMEN

Retinal neovascularization, or pathological angiogenesis in the retina, is a leading cause of blindness in developed countries. Transforming growth factor-ß-activated kinase 1 (TAK1) is a mitogen-activated protein kinase kinase kinase (MAPKKK) activated by TGF-ß1 and other proinflammatory cytokines. TAK1 is also a key mediator of proinflammatory signals and plays an important role in maintaining vascular integrity upon proinflammatory cytokine stimulation such as TNFα. However, its role in pathological angiogenesis, particularly in retinal neovascularization, remains unclear. Here, we investigate the regulatory role of TAK1 in human endothelial cells responding to inflammatory stimuli and in a rat model of oxygen-induced retinopathy (OIR) featured retinal neovascularization. Using TAK1 knockout human endothelial cells that subjected to inflammatory stimuli, transcriptome analysis revealed that TAK1 is required for activation of NFκB signaling and mediates its downstream gene expression related to endothelial activation and angiogenesis. Moreover, pharmacological inhibition of TAK1 by 5Z-7-oxozeaenol attenuated angiogenic activities of endothelial cells. Transcriptome analysis also revealed enrichment of TAK1-mediated NFκB signaling pathway in the retina of OIR rats and retinal neovascular membrane from patients with proliferative diabetic retinopathy. Intravitreal injection of 5Z-7-oxozeaenol significantly reduced hypoxia-induced inflammation and microglial activation, thus attenuating aberrant retinal angiogenesis in OIR rats. Our data suggest that inhibition of TAK1 may have therapeutic potential for the treatment of retinal neovascular pathologies.


Asunto(s)
Enfermedades de la Retina , Neovascularización Retiniana , Animales , Humanos , Ratones , Ratas , Citocinas/uso terapéutico , Modelos Animales de Enfermedad , Células Endoteliales/metabolismo , Lactonas/uso terapéutico , Ratones Endogámicos C57BL , Neovascularización Patológica/patología , FN-kappa B , Oxígeno , Enfermedades de la Retina/patología , Neovascularización Retiniana/metabolismo
5.
Dig Dis Sci ; 68(9): 3644-3659, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37526905

RESUMEN

BACKGROUND: Nintedanib (Ninte) has been approved for the treatment of pulmonary fibrosis, and whether it can ameliorate chronic pancreatitis (CP) is unknown. AIMS: This study was conducted to investigate the effect and molecular mechanism of Ninte on pancreatic fibrosis and inflammation in vivo and in vitro. METHODS: The caerulein-induced CP model of murine was applied, and Ninte was orally administered. Pathological changes in pancreas were evaluated using hematoxylin & eosin, Sirius Red, Masson's trichrome, and anti-Ki-67 staining. For in vitro studies, the effects of Ninte on cell viability, apoptosis, and migration of pancreatic stellate cells (PSCs) were determined by CCK-8, flow cytometry, and wound healing assays, respectively. The potential molecular mechanisms of the effects of Ninte on PSCs were analyzed by RNA-Seq and verified at the gene expression and protein activity levels by qRT-PCR and Western Blot. RESULTS: Ninte significantly alleviated the weight loss in mice with caerulein-induced CP and simultaneously attenuated the pancreatic damage, as evidenced by reduced acinar atrophy, collagen deposition, infiltration of inflammatory cells, and inhibited cell proliferation/regeneration. Besides, Ninte markedly suppressed the transcription of fibrogenic and proinflammatory genes in pancreatic tissues. Further in vitro studies showed that Ninte significantly inhibited the transcription and protein expression of genes corresponding to fibrogenesis and proliferation in PSCs. The results of RNA-Seq analysis and subsequent verification assays indicated that Ninte inhibited the activation and proliferation of PSCs via the JAK/STAT3 and ERK1/2 pathways. CONCLUSIONS: These findings indicate that Ninte may be a potential anti-inflammatory and anti-fibrotic therapeutic agent for CP.


Asunto(s)
Sistema de Señalización de MAP Quinasas , Pancreatitis Crónica , Ratones , Animales , Células Estrelladas Pancreáticas/patología , Ceruletida/toxicidad , Pancreatitis Crónica/inducido químicamente , Pancreatitis Crónica/tratamiento farmacológico , Pancreatitis Crónica/metabolismo , Páncreas/patología , Fibrosis
6.
Mol Ther ; 30(9): 2923-2932, 2022 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-35799444

RESUMEN

The prime editor is a versatile tool for targeted precise editing to generate point mutations, small insertions, or small deletions in eukaryotes. However, canonical PE3 system is less efficient, notably in primary cells or pluripotent stem cells. Here, we employed RNA polymerase II promoter instead of RNA polymerase III promoter, whose application is limited by specific DNA contexts, to produce Csy4-processed intronic prime editing guide RNAs (pegRNAs) and, together with other optimizations, achieved efficient targeting with poly(T)-containing pegRNAs, as well as combinatorial and conditional genetic editing. We also found simultaneous suppression of both DNA mismatch repair and DNA damage response could achieve efficient and accurate editing in human embryonic stem cells. These findings relieve the restrictions of RNA polymerase III (RNA-Pol-III)-based base editors and broadened the applications of prime editing.


Asunto(s)
Sistemas CRISPR-Cas , Edición Génica , ARN Polimerasa II , Humanos , Regiones Promotoras Genéticas , ARN Polimerasa II/genética , ARN Polimerasa III/genética , ARN Guía de Kinetoplastida/genética
7.
Appl Opt ; 62(5): 1274-1278, 2023 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-36821227

RESUMEN

A ∼2.1-µm laser is within an atmospheric transmission window and can be used in remote sensing. In this work, a 1064-nm laser was used as the pump source, pressurized hydrogen was used as the Raman active medium, and a dual-wavelength ∼2.1-µm Raman laser was generated. The 2147-nm laser was generated by a combination processes of stimulated vibrational Raman scattering and stimulated rotational Raman scattering, while a 2132-nm laser was generated by stimulated S-branch vibrational Raman scattering. Optimizing experimental conditions yielded a maximum pulse energy of 76.1 mJ, a peak power of ∼9.2M W, and a photon conversion efficiency of 29.8%.

8.
Biochem J ; 479(5): 629-640, 2022 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-35175311

RESUMEN

Iodide (I-) is crucial to thyroid function, and its regulation in thyrocytes involves ion transporters and reactive oxygen species (ROS). However, the extent of 2Cl-/H+ exchanger (ClC-3) involvement in the iodide (I-) efflux from thyrocytes remains unclear. Therefore, we examined the effects of ClC-3 on I- efflux. ClC-3 expression was found to significantly alter the serum TT3 and TT4 concentrations in mice. We further found that excess I- stimulation affected ClC-3 expression, distribution, and I- efflux in FRTL-5 cells. Immunofluorescence analyses indicated that ClC-3 mainly accumulated in the cell membrane and co-localized with ß-tubulins after 24 h of excess I- treatment, and that this process depended on ROS production. Thus, ClC-3 may be involved in I- efflux at the apical pole of thyrocytes via excess I--induced ROS production and ß-tubulin polymerization. Our results reveal novel insights into the role of ClC-3 in I- transport and thyroid function.


Asunto(s)
Canales de Cloruro/metabolismo , Células Epiteliales Tiroideas , Animales , Transporte Biológico , Yoduros , Ratones , Protones , Especies Reactivas de Oxígeno , Tubulina (Proteína)
9.
J Cell Biochem ; 123(2): 450-468, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34825407

RESUMEN

Exploiting human mesenchymal stem cells (hMSCs) was proposed as a promising therapeutic approach for cardiovascular disease due to their capacity to differentiate into cardiac cells. Though modulation of the intracellular signaling pathways dominantly WNT/ß catenin and transforming growth factor-ß (TGF-ß) have been reported to promote differentiation of hMSCs into cardiomyocytes in the prevailing literature, a safe and reproducible system for their clinical application has not yet turned into reality. In the present study, the molecular docking-based strategy was first applied for evaluating the potency of some natural phenolic compounds in the modulation of Wnt and TGF-ß signaling pathways using a vital class of crystallographic protein structures of WNT signaling regulators such as Frizzled, Disheveled, GSK3-ß, ß-catenin, LRP 5/6 extracellular domain, Tankyrase and their variety of active pockets. Then, the impacts of plant-derived chemical compounds on the regulation of the relevant signals for the differentiation of hMSCs into the definitive mesoderm lineage and cardiac progenitors were assessed in vitro. Data obtained revealed the synergistic activity of Wnt and TGF-ß superfamily to direct cardiac differentiation in human cardiogenesis by comparing cardiac gene expression in the presence and absence of the TGF-ß inhibitors. We found that the inhibitory effect of canonical Wnt/ß-catenin is sufficient to cause proper cardiomyocyte differentiation, but the TGF-ß pathway plays a vital role in enhancing the expression of the cardiomyocyte-specific marker (cTnT). It was found that quercetin, a p38MAPK inhibitor with the high energy dock to the active pocket of Wnt receptors, promotes cardiac differentiation via the inhibition of both Wnt and non-Smad TGF-ß pathways. Altogether, data presented here can contribute to the development of a feasible and efficient cardiac differentiation protocol as an "off-the-shelf" therapeutic source using novel natural agents for cardiac repair or regeneration.


Asunto(s)
Tejido Adiposo/metabolismo , Diferenciación Celular/efectos de los fármacos , Células Madre Mesenquimatosas/metabolismo , Miocitos Cardíacos/metabolismo , Quercetina/farmacología , Factor de Crecimiento Transformador beta/metabolismo , Vía de Señalización Wnt/efectos de los fármacos , Línea Celular , Humanos
10.
Br J Cancer ; 126(7): 1055-1066, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34952931

RESUMEN

BACKGROUND: The main therapy for colon cancer with liver metastasis is chemotherapy based on 5-fluorouracil combined with targeted drugs. However, acquired drug resistance and severe adverse reactions limit patients' benefit from standard chemotherapy. Here, we investigate the involvement of endogenous hydrogen sulfide (H2S) in liver metastasis of colon cancer and its potential value as a novel therapeutic target. METHODS: We used the CRISPR/Cas9 system to knockdown CBS gene expression in colon cancer cell lines. PCR arrays and proteome arrays were applied to detect the transcription and protein expression levels, respectively, of angiogenesis-related genes after knockdown. The molecular mechanism was investigated by western blot analysis, RT-qPCR, immunofluorescence staining, ChIP assays and dual-luciferase reporter assays. A liver metastasis mouse model was adopted to investigate the effect of targeting CBS on tumour metastasis in vivo. RESULTS: Knockdown of CBS decreased the metastasis and invasion of colon cancer cells and inhibited angiogenesis both in vivo and in vitro. Tissue microarray analysis showed a positive correlation between CBS and VEGF expression in colon cancer tissues. Further analysis at the molecular level validated a positive feedback loop between the CBS-H2S axis and VEGF. CONCLUSIONS: Endogenous H2S promotes angiogenesis and metastasis in colon cancer, and targeting the positive feedback loop between the CBS-H2S axis and VEGF can effectively intervene in liver metastasis of colon cancer.


Asunto(s)
Neoplasias del Colon , Sulfuro de Hidrógeno/metabolismo , Neoplasias Hepáticas , Animales , Proliferación Celular , Neoplasias del Colon/complicaciones , Cistationina betasintasa/genética , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/secundario , Ratones , Factor de Transcripción AP-1/genética , Factor A de Crecimiento Endotelial Vascular/genética
11.
Cancer Cell Int ; 22(1): 85, 2022 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-35172821

RESUMEN

BACKGROUND: The role of hydrogen sulfide (H2S) in cancer biology is controversial, including colorectal cancer. The bell-shaped effect of H2S refers to pro-cancer action at lower doses and anti-cancer effect at higher concentrations. We hypothesized that overexpression of cystathionine-beta-synthase (CBS)/H2S exerts an inhibitory effect on colon cancer cell proliferation and metastasis. METHODS: Cell proliferation was assessed by Cell Counting Kit-8 (CCK-8), clone-formation and sphere formation assay. Cell migration was evaluated by transwell migration assay. Intracellular H2S was detected by H2S probe. Chromatin immunoprecipitation (ChIP) analysis was carried out to examine DNA-protein interaction. Cell experiments also included western blotting, flow cytometry, immunohistochemistry (IHC) and immunofluorescence analysis. We further conducted in vivo experiments to confirm our conclusions. RESULTS: Overexpression of CBS and exogenous H2S inhibited colon cancer cell proliferation and migration in vitro. In addition, overexpression of CBS attenuated tumor growth and liver metastasis in vivo. Furthermore, CD44 and the transcription factor SP-1 was probably involved in the inhibitory effect of CBS/H2S axis on colon cancer cells. CONCLUSIONS: Overexpression of CBS and exogenous provision of H2S inhibited colon cancer cell proliferation and migration both in vivo and in vitro. Molecular mechanisms might involve the participation of CD44 and the transcription factor SP-1.

12.
FASEB J ; 35(7): e21720, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34110642

RESUMEN

Methylation of circulating free DNA (CfDNA) has emerged as an efficient marker of tumor screening and prognostics. However, no efficient methylation marker has been developed for monitoring liver metastasis (LM) in colorectal cancer (CRC). Utilizing methylome profiling and bisulfite sequencing polymerase chain reaction of paired primary and LM sites, significantly increased methylation of TCHH was identified in the process of LM in CRC in the present study. Methylight analysis of TCHH methylation in CfDNA displayed a promisingly discriminative power between CRC with and without LM. Besides, significant coefficient of TCHH methylation and LM tumor volume was also validated. Together, these results indicated the potential of TCHH methylation in CfDNA as a monitoring marker of LM in CRC.


Asunto(s)
Antígenos/genética , Biomarcadores de Tumor/genética , Ácidos Nucleicos Libres de Células/genética , Neoplasias Colorrectales/genética , Metilación de ADN/genética , ADN de Neoplasias/genética , Proteínas de Filamentos Intermediarios/genética , Neoplasias Hepáticas/genética , Neoplasias Colorrectales/patología , Epigenoma/genética , Humanos , Neoplasias Hepáticas/patología , Pronóstico
13.
Gastric Cancer ; 25(3): 503-514, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-34826008

RESUMEN

BACKGROUND: Fibroblasts are the predominant cell type in the stroma of tumor, and cancer-associated fibroblasts (CAFs) promote cancer chemoresistance by secreting various bioactive molecules. However, the differential expression between CAFs and normal fibroblasts (NFs) and how can CAFs uniquely impact cancer cells are still unexplored. METHODS: Primary CAFs and NFs were cultured from gastric cancer specimens, and their variant expression was analyzed by RNA-sequencing. Chemoresistance was evaluated by measuring cell viability, apoptosis, and 3D-coculture techniques. RESULTS: CAFs were isolated from gastric cancers and defined by specific cell-surface markers. CAFs decreased the sensitivity of gastric cancer cells to 5-FU. RNA-sequencing showed that CAFs expressed a higher level of NRP2 than NFs. And the high expression of NRP2 was correlated with worse oncological outcomes in gastric cancer patients. Further study showed that the knockdown of NRP2 eradicated the resistance to 5-FU. And the secretion of stromal cell-derived factor-1 (SDF-1) was reduced following NRP2 knockdown. Furthermore, we found that the increased sensitivity to 5-FU was induced by DNA damage. And this process was mediated by predominant effectors of the Hippo pathway, YAP/TAZ. CONCLUSIONS: The present study indicated that CAFs within gastric cancers promote chemoresistance through the expression of NRP2. The secretion of SDF-1 that mediated by VEGF/NRP2 signaling in CAFs and the activation of Hippo pathway in cancer cells in large part participated in this project.


Asunto(s)
Fibroblastos Asociados al Cáncer , Neoplasias Gástricas , Fibroblastos Asociados al Cáncer/patología , Línea Celular Tumoral , Proliferación Celular/fisiología , Resistencia a Antineoplásicos , Fibroblastos/patología , Fluorouracilo/farmacología , Humanos , ARN/metabolismo , Neoplasias Gástricas/patología
14.
Acta Pharmacol Sin ; 43(2): 367-375, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33875797

RESUMEN

The excess deposition of underlying extracellular matrix (ECM) in adipose tissue is defined as adipose tissue fibrosis that is a major contributor to metabolic disorder such as obesity and type 2 diabetes. Anti-fibrosis therapy has received much attention in the treatment of metabolic disorders. Orosomucoid (ORM) is an acute-phase protein mainly produced by liver, which is also an adipokine. In this study, we investigated the effects of ORM on adipose tissue fibrosis and the potential mechanisms. We showed that ORM1-deficient mice exhibited an obese phenotype, manifested by excessive collagen deposition in adipose tissues and elevated expression of ECM regulators such as metalloproteinases (MMP-2, MMP-13, MMP-14) and tissue inhibitors of metalloproteinases (TIMP-1, TIMP-2, TIMP-3). Administration of exogenous ORM (50 mg· kg-1· d-1, ip) for 7 consecutive days in high-fat diet (HFD)-fed mice and leptin receptor (LepR)-deficient db/db mice attenuated these abnormal expressions. Meanwhile, ORM administration stimulated AMP-activated protein kinase (AMPK) phosphorylation and decreased transforming growth factor-ß1 (TGF-ß1) level in adipose tissues of the mice. In TGF-ß1-treated 3T3-L1 fibroblasts, ORM (10 µg/mL) improved the impaired expression profiles of fibrosis-related genes, whereas a selective AMPK inhibitor dorsomorphin (1 µmol/mL) abolished these effects. Together, our results suggest that ORM exerts a direct anti-fibrosis effect in adipose tissue via AMPK activation. ORM is expected to become a novel target for the treatment of adipose tissue fibrosis.


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Adipoquinas/farmacología , Tejido Adiposo/efectos de los fármacos , Orosomucoide/farmacología , Transducción de Señal/efectos de los fármacos , Células 3T3 , Tejido Adiposo/diagnóstico por imagen , Tejido Adiposo/metabolismo , Tejido Adiposo/patología , Animales , Western Blotting , Dieta Alta en Grasa/efectos adversos , Fibrosis , Imagen por Resonancia Magnética , Masculino , Ratones , Ratones Endogámicos C57BL , Orosomucoide/deficiencia
15.
Cell Mol Life Sci ; 78(6): 2683-2708, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33388855

RESUMEN

The clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated (Cas) system provides a groundbreaking genetic technology that allows scientists to modify genes by targeting specific genomic sites. Due to the relative simplicity and versatility of the CRISPR/Cas system, it has been extensively applied in human genetic research as well as in agricultural applications, such as improving crops. Since the gene editing activity of the CRISPR/Cas system largely depends on the efficiency of introducing the system into cells or tissues, an efficient and specific delivery system is critical for applying CRISPR/Cas technology. However, there are still some hurdles remaining for the translatability of CRISPR/Cas system. In this review, we summarized the approaches used for the delivery of the CRISPR/Cas system in mammals, plants, and aquacultures. We further discussed the aspects of delivery that can be improved to elevate the potential for CRISPR/Cas translatability.


Asunto(s)
Sistemas CRISPR-Cas/genética , Edición Génica/métodos , Animales , Técnicas de Transferencia de Gen , Vectores Genéticos/genética , Vectores Genéticos/metabolismo , Humanos , Inmunidad , Lentivirus/genética , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo
16.
Mol Microbiol ; 114(2): 279-291, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32259388

RESUMEN

Bacterial flagella are nanomachines that drive bacteria motility and taxis in response to environmental changes. Whether flagella are permanent cell structures and, if not, the circumstances and timing of their production and loss during the bacterial life cycle remain poorly understood. Here we used the single polar flagellum of Vibrio alginolyticus as our model and implementing in vivo fluorescence imaging revealed that the percentage of flagellated bacteria (PFB) in a population varies substantially across different growth phases. In the early-exponential phase, the PFB increases rapidly through the widespread production of flagella. In the mid-exponential phase, the PFB peaks at around 76% and the partitioning of flagella between the daughter cells are 1:1 and strictly at the old poles. After entering the stationary phase, the PFB starts to decline, mainly because daughter cells stop making new flagella after cell division. Interestingly, we observed that bacteria can actively abandon flagella after prolonged stationary culturing, though cell division has long been suspended. Further experimental investigations confirmed that flagella were ejected in V. alginolyticus, starting from breakage in the rod. Our results highlight the dynamic production and loss of flagella during the bacterial life cycle. IMPORTANCE: Flagella motility is critical for many bacterial species. The bacterial flagellum is made up of about 20 different types of proteins in its final structure and can be self-assembled. The current understanding of the lifetime and durability of bacterial flagella is very limited. In the present study, we monitored Vibrio alginolyticus flagellar assembly and loss by in vivo fluorescence labeling, and found that the percentage of flagellated bacteria varies substantially across different growth phases. The production of flagella was synchronized with cell growth but stopped when cells entered the stationary phase. Surprisingly, we observed that bacteria can actively abandon flagella after prolonged stationary culturing, as well as in the low glucose buffering medium. We then confirmed the ejection of flagella in V. alginolyticus started with breakage of the rod. Our results highlight the dynamic production and loss of flagella during the bacterial life cycle.


Asunto(s)
Flagelos/metabolismo , Vibrio alginolyticus/metabolismo , Proteínas Bacterianas/metabolismo , Ciclo Celular/genética , División Celular/fisiología , Flagelos/fisiología , Regulación Bacteriana de la Expresión Génica/genética , Microscopía Fluorescente/métodos , Imagen Óptica/métodos , Vibrio alginolyticus/citología
17.
Biochem Biophys Res Commun ; 558: 134-140, 2021 06 18.
Artículo en Inglés | MEDLINE | ID: mdl-33910127

RESUMEN

Previous studies have shown that secreted protein acidic and rich in cysteine (SPARC) proteins can inhibit the development of cancer cells in various ways, such as by inhibiting angiogenesis and inhibiting cell proliferation. In fact, SPARC proteins may have an effect on the chemoresistance of gastric cancer cells to 5-Fluorouracil (5-FU), which needs further research in the future. Therefore, the purpose of this study was to explore the relationship between SPARC proteins and the chemosensitivity of gastric cancer cells to 5-FU. In vitro, after SPARC protein levels were regulated by plasmid, siRNA and human recombinant SPARC protein transfection in MGC-803, SGC-7901 and BGC-823 cells, we detected epithelial-mesenchymal transition (EMT), apoptosis markers and cell viability after 5-FU treatment. In vivo, we implanted BGC-823 cells with stable SPARC overexpression into nude mice. Tumour size was measured to assess the effect of SPARC protein on tumour formation and 5-FU chemosensitivity. In SGC-7901 and BGC-823 cells, both endogenous and exogenous upregulation of SPARC protein levels decreased cell viability, destroyed cytoskeletal F-actin, inhibited cell migration, and downregulated a series of transcription factors to inhibit cell EMT; it also upregulated cell apoptosis-related proteins to promote cell apoptosis. However, we obtained opposite results in SPARC knockdown MGC-803 cells. In vivo, compared with the control group, the group engrafted with BGC-823 cells stably overexpressing SPARC had a significant smaller tumour size. After 5-FU treatment, the new tumour gradually decreased in size. Our results show that the SPARC protein could enhance 5-FU chemosensitivity in gastric cancer cell lines by inhibiting EMT and promoting cell apoptosis.


Asunto(s)
Fluorouracilo/farmacología , Osteonectina/metabolismo , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/metabolismo , Actinas/metabolismo , Animales , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Caspasa 3/metabolismo , Línea Celular Tumoral , Resistencia a Antineoplásicos/fisiología , Transición Epitelial-Mesenquimal/efectos de los fármacos , Transición Epitelial-Mesenquimal/fisiología , Femenino , Técnicas de Silenciamiento del Gen , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Osteonectina/antagonistas & inhibidores , Osteonectina/genética , Poli(ADP-Ribosa) Polimerasas/metabolismo , ARN Interferente Pequeño/genética , Neoplasias Gástricas/patología , Regulación hacia Arriba , Ensayos Antitumor por Modelo de Xenoinjerto
18.
Mol Ther ; 28(10): 2120-2138, 2020 10 07.
Artículo en Inglés | MEDLINE | ID: mdl-32649860

RESUMEN

Aberrant growth of blood vessels (neovascularization) is a key feature of severe eye diseases that can cause legal blindness, including neovascular age-related macular degeneration (nAMD) and diabetic retinopathy (DR). The development of anti-vascular endothelial growth factor (VEGF) agents has revolutionized the treatment of ocular neovascularization. Novel proangiogenic targets, such as angiopoietin and platelet-derived growth factor (PDGF), are under development for patients who respond poorly to anti-VEGF therapy and to reduce adverse effects from long-term VEGF inhibition. A rapidly advancing area is gene therapy, which may provide significant therapeutic benefits. Viral vector-mediated transgene delivery provides the potential for continuous production of antiangiogenic proteins, which would avoid the need for repeated anti-VEGF injections. Gene silencing with RNA interference to target ocular angiogenesis has been investigated in clinical trials. Proof-of-concept gene therapy studies using gene-editing tools such as CRISPR-Cas have already been shown to be effective in suppressing neovascularization in animal models, highlighting the therapeutic potential of the system for treatment of aberrant ocular angiogenesis. This review provides updates on the development of anti-VEGF agents and novel antiangiogenic targets. We also summarize current gene therapy strategies already in clinical trials and those with the latest approaches utilizing CRISPR-Cas gene editing against aberrant ocular neovascularization.


Asunto(s)
Oftalmopatías/patología , Oftalmopatías/terapia , Terapia Genética , Neovascularización Patológica/terapia , Animales , Sistemas CRISPR-Cas , Ensayos Clínicos como Asunto , Manejo de la Enfermedad , Susceptibilidad a Enfermedades , Oftalmopatías/etiología , Edición Génica , Terapia Genética/métodos , Humanos , Neovascularización Patológica/genética , Factor de Crecimiento Derivado de Plaquetas/genética , Factor de Crecimiento Derivado de Plaquetas/metabolismo , Resultado del Tratamiento , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo
19.
Nucleic Acids Res ; 47(D1): D203-D211, 2019 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-30239819

RESUMEN

Post-transcriptional regulation of RNAs is critical to the diverse range of cellular processes. The volume of functional genomic data focusing on post-transcriptional regulation logics continues to grow in recent years. In the current database version, POSTAR2 (http://lulab.life.tsinghua.edu.cn/postar), we included the following new features and data: updated ∼500 CLIP-seq datasets (∼1200 CLIP-seq datasets in total) from six species, including human, mouse, fly, worm, Arabidopsis and yeast; added a new module 'Translatome', which is derived from Ribo-seq datasets and contains ∼36 million open reading frames (ORFs) in the genomes from the six species; updated and unified post-transcriptional regulation and variation data. Finally, we improved web interfaces for searching and visualizing protein-RNA interactions with multi-layer information. Meanwhile, we also merged our CLIPdb database into POSTAR2. POSTAR2 will help researchers investigate the post-transcriptional regulatory logics coordinated by RNA-binding proteins and translational landscape of cellular RNAs.


Asunto(s)
Biología Computacional , Bases de Datos Genéticas , Regulación de la Expresión Génica , Procesamiento Postranscripcional del ARN , Animales , Sitios de Unión , Biología Computacional/métodos , Humanos , Inmunoprecipitación , Anotación de Secuencia Molecular , Sistemas de Lectura Abierta , Unión Proteica , Proteínas de Unión al ARN/metabolismo , Análisis de Secuencia de ADN , Navegador Web
20.
Nanomedicine ; 34: 102369, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33636347

RESUMEN

Combination chemotherapy with two or more complimentary drugs has been widely used for clinical cancer treatment. However, the efficacy and side effects of combination chemotherapy still remain a challenge. Here, we constructed an albumin-stabilized layered double hydroxide nanoparticle (BLDH) system to simultaneously load and deliver two widely used anti-tumor drugs, i.e. 5-fluorouracil (5FU) and albumin-bound PTX (Abraxane, ABX) for colorectal cancer treatment. The cellular uptake test has revealed that 5FU-ABX encapsulated BLDH (BLDH/5FU-ABX) nanoparticles were efficiently internalized by the colorectal cancer cell (HCT-116), synergistically inducing apoptosis of colon cancer cells. The in vivo test has demonstrated that BLDH/5FU-ABX nanomedicine significantly inhibited the tumor growth after three intravenous injections, without any detectable side effects. The enhanced therapeutic effectiveness is attributed to efficient accumulation of BLDH/5FU-ABX at tumor sites and acid-sensitive release of co-loaded drugs. Thus, combination chemotherapy based on BLDH/5FU-ABX nanomedicine would be a new strategy for colorectal cancer treatment.


Asunto(s)
Albúminas/química , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Colorrectales/tratamiento farmacológico , Hidróxidos/química , Nanomedicina , Nanopartículas/química , Paclitaxel Unido a Albúmina/administración & dosificación , Paclitaxel Unido a Albúmina/uso terapéutico , Animales , Sinergismo Farmacológico , Femenino , Fluorouracilo/administración & dosificación , Fluorouracilo/uso terapéutico , Células HCT116 , Humanos , Inyecciones Intravenosas , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Ensayos Antitumor por Modelo de Xenoinjerto
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