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1.
J Nat Prod ; 87(1): 2-13, 2024 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-38117981

RESUMEN

The glucose transporter 1 (GLUT1) protein is involved in the basal-level absorption of glucose in tumor cells. Inhibiting GLUT1 decreases tumor cell proliferation and induces tumor cell damage. Natural GLUT1 inhibitors have been studied only to a small extent, and the structures of known natural GLUT1 inhibitors are limited to a few classes of natural products. Therefore, discovering and researching other natural GLUT1 inhibitors with novel scaffolds are essential. Physalis angulata L. var. villosa is a plant known as Mao-Ku-Zhi (MKZ). Withanolides are the main phytochemical components of MKZ. MKZ extracts and the components of MKZ exhibited antitumor activity in recent pharmacological studies. However, the antitumor-active components of MKZ and their molecular mechanisms remain unknown. A cell membrane-biomimetic nanoplatform (CM@Fe3O4/MIL-101) was used for target separation of potential GLUT1 inhibitors from MKZ. A new withanolide, physagulide Y (2), together with six known withanolides (1, 3-7), was identified as a potential GLUT1 inhibitor. Physagulide Y was the most potent GLUT1 inhibitor, and its antitumor activity and possible mechanism of action were explored in MCF-7 human cancer cells. These findings advance the development of technologies for the targeted separation of natural products and identify a new molecular framework for the investigation of natural GLUT1 inhibitors.


Asunto(s)
Antineoplásicos Fitogénicos , Physalis , Witanólidos , Humanos , Physalis/química , Transportador de Glucosa de Tipo 1 , Antineoplásicos Fitogénicos/farmacología , Antineoplásicos Fitogénicos/química , Proteínas Facilitadoras del Transporte de la Glucosa , Extractos Vegetales/química , Witanólidos/farmacología , Witanólidos/química , Proteínas de Transporte de Membrana , Estructura Molecular
2.
PLoS One ; 19(8): e0306785, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39150972

RESUMEN

BACKGROUND: Although COVID-19 has brought serious disasters to all mankind, it has also accelerated the innovation and application of educational science and technology. China is the first to bear in COVID-19, and in order to minimize the impact of the field of education and teaching involving a large number of students, educational technology has entered a stage of continuous innovation and large-scale application, especially in higher education institutions. PURPOSE: Firstly, it introduces the progress and achievements of China's educational science and technology innovation during the COVID-19 epidemic, as well as the in-depth application of it in education for studying abroad in China. Secondly, the problems and gaps of STI in education for studying abroad in China are analyzed. Once again, it puts forward the solution countermeasures and future development strategies for the science and technology innovation of education abroad in China. METHODS: A cross-sectional survey of 258 international students from 20 universities was conducted using a self-administered questionnaire entitled "Research on Innovation and Application of Science and Technology in China's International Education under the Situation of Conventional COVID-19 Epidemic Prevention and Control". RESULTS: It will put forward opinions and suggestions to promote the deepening and improvement of China's education science and technology innovation and application, as well as to provide a commentary and theoretical contribution to similar issues and phenomena around the world. CONCLUSION: Through in-depth research and analysis, it is found that the application of science, technology and innovation has played a great role in China's study abroad education, which not only improves the quality and effect of teaching, but also enriches the means and methods of teaching.


Asunto(s)
COVID-19 , Estudiantes , COVID-19/epidemiología , COVID-19/prevención & control , China/epidemiología , Humanos , Estudios Transversales , Universidades , Encuestas y Cuestionarios , Invenciones , Masculino , Femenino , SARS-CoV-2 , Tecnología Educacional , Ciencia/educación , Tecnología/educación , Adulto Joven , Pueblos del Este de Asia
3.
Artículo en Inglés | MEDLINE | ID: mdl-36657998

RESUMEN

Apoptosis mediated by reactive oxygen species (ROS) has emerged as a promising therapeutic strategy for tumors. However, the overexpression of NAD(P)H:quinone oxidoreductase 1 (NQO1) protein restricted ROS production through a negative feedback pathway in tumor cells, promoting tumor progression, and weakening the effect of drug therapy. Here, a PROTACs nanodrug delivery system (PN) was constructed to increase ROS generation by degrading the NQO1 protein. Specifically, a PROTAC (proteolytic targeting chimera) molecule DQ was designed and synthesized. Then DQ and withaferin A (WA, an inducer of ROS) were loaded into PNs. DQ degraded the overexpressed NQO1 protein in tumor cells through a protein ubiquitination degradation pathway, thereby weakening the antioxidant capacity of tumor cells. Meanwhile, the reduction of NQO1 could inhibit the negative feedback effect of ROS production, thus increasing ROS generation. It has been demonstrated that PNs can significantly increase ROS production and possess potent antitumor properties in vitro and in vivo. This nanoplatform may offer an alternative approach to treating tumors with NQO1 overexpression.

4.
Acta Biomater ; 146: 465-477, 2022 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-35526738

RESUMEN

With the development of redox-related therapy modalities in cancer therapy, photodynamic therapy (PDT) has gradually become the most widely used type in the clinic. However, the hypoxic tumor microenvironment restricted the curative effect of PDT. Here, a strategic hypoxia relief nanodrug delivery system (SHRN) with a synergetic strategy was designed to alleviate tumor hypoxia on the basis of PDT. Specifically, the oxygen producer MnO2, oxygen consumption inhibitor atovaquone (ATO) and photosensitizer hypericin (HY) were loaded in SHRN. MnO2 reacted with excess H2O2 in the tumor microenvironment to increase oxygen generation, while ATO inhibited electron transfer in the aerobic respiratory chain to decrease oxygen consumption. Then, HY utilized this sufficient oxygen to produce ROS under irradiation to enhance the PDT effect. In vitro and in vivo assays confirmed that SHRN exhibits powerful and overall antitumor PDT effects. This formulation may provide an alternative strategy for the development of PDT effects in hypoxic tumor microenvironments. STATEMENT OF SIGNIFICANCE: We constructed a strategic hypoxia relief nanodrug delivery system (SHRN) with a synergetic strategy to alleviate tumor hypoxia on the basis of photodynamic therapy (PDT). This work uniquely aimed at not only increased O2 generation in hypoxic tumor microenvironment but also reduced O2 consumption. Moreover, we designed a nanodrug delivery system to enhance the tumor permeability of SHRN. In vitro and in vivo assays all confirmed that SHRN exhibited powerful and overall antitumor effects. This formulation may provide an alternative strategy for the development of the PDT effect in hypoxic solid tumor.


Asunto(s)
Neoplasias , Fotoquimioterapia , Línea Celular Tumoral , Humanos , Peróxido de Hidrógeno , Hipoxia , Compuestos de Manganeso , Neoplasias/tratamiento farmacológico , Óxidos , Oxígeno , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/uso terapéutico , Microambiente Tumoral
5.
Chin J Nat Med ; 20(4): 241-257, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35487595

RESUMEN

Lysine specific demethylase 1 (LSD1), a transcriptional corepressor or coactivator that serves as a demethylase of histone 3 lysine 4 and 9, has become a potential therapeutic target for cancer therapy. LSD1 mediates many cellular signaling pathways and regulates cancer cell proliferation, invasion, migration, and differentiation. Recent research has focused on the exploration of its pharmacological inhibitors. Natural products are a major source of compounds with abundant scaffold diversity and structural complexity, which have made a major contribution to drug discovery, particularly anticancer agents. In this review, we briefly highlight recent advances in natural LSD1 inhibitors over the past decade. We present a comprehensive review on their discovery and identification process, natural plant sources, chemical structures, anticancer effects, and structure-activity relationships, and finally provide our perspective on the development of novel natural LSD1 inhibitors for cancer therapy.


Asunto(s)
Antineoplásicos , Neoplasias , Antineoplásicos/química , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/uso terapéutico , Histona Demetilasas/química , Histona Demetilasas/metabolismo , Humanos , Lisina/uso terapéutico , Neoplasias/tratamiento farmacológico
6.
J Colloid Interface Sci ; 609: 341-352, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34896834

RESUMEN

Photocatalytic fixation of nitrogen to ammonia (NH3) is a green but low-efficiency technology due to the high recombination of photo-generated carriers and poor light absorption of photocatalysts. Generally, the adsorption capacity for N2 and the band position of TiO2 are responsible for bandgap, light-adsorption, and the separation of photocarriers. Therefore, they play crucial roles to improve catalytic activity. Herein, N-doping TiO2 hollow microspheres (NTO-0.5) with oxygen vacancies were synthesized via a hydrothermal method using phenolic resin microsphere as a template. The obtained NTO-0.5 achieves an impressive ammonia yield of 80.09 µmol gcat-1h-1. Oxygen vacancies of NTO-0.5 were confirmed by ESR, Raman, XPS, Zeta potential, and H2O2 treatment for reducing oxygen vacancies. The ammonia yield of NTO-0.5 decreases to 34.78 µmol gcat-1h-1 after reducing oxygen vacancies by H2O2 treatment, which demonstrates the importance of oxygen vacancies. The oxygen vacancies narrow the bandgap from 3.18 eV to 2.83 eV and impede the recombination of photo-generated carriers. The hollow microspheres structure is conducive to light absorption and utilization. Therefore, the synergistic effect between the oxygen vacancies and the hollow microspheres structure boosts the efficiency of photocatalytic nitrogen fixation. After four cycles, the ammonia production yield still maintains at 76.52 µmol gcat-1h-1, meaning high stability. This work provides a new insight into the construction of catalysts with oxygen vacancies to enhance photocatalytic nitrogen fixation performance.

7.
Gene ; 730: 144322, 2020 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-31899303

RESUMEN

AIM: This study aimed to investigate the effect of 1,25-dihydroxy-vitamin D3 (1,25(OH)2D3) on primary chondrocytes cultured from patients with osteoarthritis (OA). METHOD: Primary chondrocytes isolated from the tibial plateau of female OA patients were characterized by immunocytochemistry analysis. Using Cell Counting Kit-8 (CCK-8), cell viability was measured to select suitable 1,25(OH)2D3 concentrations for treating chondrocytes. RNA-sequencing was performed on primary chondrocytes treated with or without 1,25(OH)2D3. Differentially expressed genes (DEGs) as well as gene ontology (GO)-biological process (BP) and pathways affected by 1,25(OH)2D3 were identified. Protein-protein interaction (PPI) network was constructed, and the hub nodes in the PPI network were identified. qRT-PCR was conducted to confirm the expression levels of six DEGs. RESULTS: Positive collagen II staining confirmed the successful isolation of primary chondrocytes. CCK-8 assay showed maximal primary chondrocyte survival rate when treated with 10-5 µmol/L of 1,25(OH)2D3 for 72 h. RNA-sequencing results identified a total of 1036 DEGs, including 593 upregulated and 443 downregulated genes from 1,25(OH)2D3 treated and untreated cells. Further functional enrichment analyses showed the association of these DEGs with GO-BP terms such as response to the stimulus, cell proliferation, angiogenesis, and regulation of cell motility, and KEGG pathways, including TNF signaling pathway, IL-17 signaling pathway, cytokine-cytokine receptor interaction, and NF-kappa B signaling pathway. PPI network identified UBC, FOS, IFIT1, CDK1, and ISG15 as the hub nodes in the network. qRT-PCR results were in alignment with the results of RNA-sequencing. CONCLUSION: Our study might provide a theoretical basis for the use of vitamin D in treating OA.


Asunto(s)
Condrocitos/efectos de los fármacos , Vitamina D/análogos & derivados , Anciano , Femenino , Ontología de Genes , Humanos , Persona de Mediana Edad , Osteoartritis/metabolismo , Cultivo Primario de Células , Análisis de Secuencia de ARN , Transducción de Señal/efectos de los fármacos , Transcriptoma/genética , Vitamina D/metabolismo , Vitamina D/farmacología , Vitamina D/fisiología , Vitamina D/uso terapéutico , Vitaminas/farmacología
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