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The prevalence of diabetes is increasing worldwide, and it is very important to study new hypoglycemic active substances. In this study, we investigated the hypoglycemic effect of Chroogomphus rutilus crude polysaccharide (CRCP) in HepG2 cells and streptozotocin-induced diabetic mice. A glucose consumption experiment conducted in HepG2 cells demonstrated the in vitro hypoglycemic activity of CRCP. Furthermore, CRCP exhibited significant hypoglycemic effects and effectively ameliorated insulin resistance in insulin resistant HepG2 cells. In high-fat diet and streptozotocin-induced diabetic mice, after 4 weeks of CRCP administration, fasting blood glucose, fasting serum insulin, triglyceride, total cholesterol, low-density lipoprotein cholesterol, glutamate transaminase, alanine transaminase, and insulin resistance index significantly decreased, while high-density lipoprotein cholesterol and insulin sensitivity index (ISI) were markedly increased. Moreover, hematoxylin-eosin (HE) staining and immunofluorescence labeling of tissue sections indicated that CRCP attenuated the pathological damage of liver and pancreas in diabetic mice. These results indicate that CRCP is a potential hypoglycemic agent.
Assuntos
Glicemia , Diabetes Mellitus Experimental , Hipoglicemiantes , Resistência à Insulina , Polissacarídeos , Animais , Hipoglicemiantes/farmacologia , Hipoglicemiantes/química , Humanos , Diabetes Mellitus Experimental/tratamento farmacológico , Camundongos , Células Hep G2 , Masculino , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Polissacarídeos/farmacologia , Polissacarídeos/química , Fígado/efeitos dos fármacos , Fígado/metabolismo , Dieta Hiperlipídica/efeitos adversos , Insulina/sangue , Insulina/metabolismo , Pâncreas/efeitos dos fármacos , Pâncreas/patologia , Agaricales/química , Polissacarídeos Fúngicos/farmacologia , Polissacarídeos Fúngicos/química , EstreptozocinaRESUMO
The identification of Chinese medicinal herbs occupies a crucial part in the development of the food and drug market. Although molecular identification based on real-time PCR offers good versatility and uniform digital standards compared with traditional methods, such as morphology, the dependence on large-scale equipment hinders spot detection and marketable applications. In this study, we developed a DNA nanoclaw for colorimetric detection and visible on-site identification of Chinese medicines. When specific miRNA is present, the DNAzyme is activated and cleaves the substrate strand, triggering the catalytic hairpin assembly (CHA) reaction and forming branched DNA junctions on AuNP-I. This can then capture AuNP-II through hybridization and facilitate their aggregation, resulting in a noticeable color change that is observable to the naked eye. By harnessing the dual amplification of DNAzyme and CHA, this highly sensitive nanoprobe successfully achieved specific identification of Chinese medicines. This offers a new perspective for on-site testing in the herbal market.
Assuntos
Técnicas Biossensoriais , DNA Catalítico , MicroRNAs , DNA Catalítico/química , Técnicas Biossensoriais/métodos , DNA , MicroRNAs/análise , Hibridização de Ácido NucleicoRESUMO
Cancer cells undergo a significant level of "metabolic reprogramming" or "remodeling" to ensure an adequate supply of ATP and "building blocks" for cell survival and to facilitate accelerated proliferation. Cancer cells preferentially use glycolysis for ATP production (the Warburg effect); however, cancer cells, including colorectal cancer (CRC) cells, also depend on oxidative phosphorylation (OXPHOS) for ATP production, a finding that suggests that both glycolysis and OXPHOS play significant roles in facilitating cancer progression and proliferation. Our prior studies identified a semisynthetic isoflavonoid, DBI-1, that served as an AMPK activator targeting mitochondrial complex I. Furthermore, DBI-1 and a glucose transporter 1 (GLUT1) inhibitor, BAY-876, synergistically inhibited CRC cell growth in vitro and in vivo. We now report a study of the structure-activity relationships (SARs) in the isoflavonoid family in which we identified a new DBI-1 analog, namely, DBI-2, with promising properties. Here, we aimed to explore the antitumor mechanisms of DBIs and to develop new combination strategies by targeting both glycolysis and OXPHOS. We identified DBI-2 as a novel AMPK activator using an AMPK phosphorylation assay as a readout. DBI-2 inhibited mitochondrial complex I in the Seahorse assays. We performed proliferation and Western blotting assays and conducted studies of apoptosis, necrosis, and autophagy to corroborate the synergistic effects of DBI-2 and BAY-876 on CRC cells in vitro. We hypothesized that restricting the carbohydrate uptake with a KD would mimic the effects of GLUT1 inhibitors, and we found that a ketogenic diet significantly enhanced the therapeutic efficacy of DBI-2 in CRC xenograft mouse models, an outcome that suggested a potentially new approach for combination cancer therapy.
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The deregulation in the Wnt/ß-catenin signaling pathway is associated with many human cancers, particularly colorectal cancer (CRC) and, therefore, represents a promising target for drug development. We have screened over 300 semisynthetic and natural compounds using a Wnt reporter assay and identified a family of novel chalcone derivatives (CXs) that inhibited Wnt signaling and CRC cell proliferation. Among them, we selected CX258 for further in vitro and in vivo study to investigate the molecular mechanisms. We found that CX258 significantly inhibited ß-catenin expression and nuclear translocation, inducing cell cycle arrest at the G2/M phase in CRC cells. Additionally, CX258 reduced the expression of DNA Topoisomerase II alpha (TOP2A) in CRC cells. Moreover, knocking down TOP2A by siRNAs inhibited the Wnt/ß-catenin signaling pathway, a finding suggesting that CX258 inhibited Wnt/ß-catenin signaling and CRC cell proliferation at least partially by modulating TOP2A. Further studies showed that CDK1 that interacts with TOP2A was significantly reduced after TOP2A knockdown. We demonstrated that CX258 significantly inhibited DLD-1 CRC cell xenografts in SCID mice. In summary, we identified CX258 as a promising candidate for colorectal cancer treatment by targeting the TOP2A/Wnt/ß-catenin signaling pathway.
Assuntos
Chalconas , Neoplasias Colorretais , Animais , Camundongos , Humanos , Via de Sinalização Wnt/genética , Chalconas/farmacologia , Chalconas/uso terapêutico , beta Catenina/metabolismo , Camundongos SCID , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismoRESUMO
Cancer cells undergo significant "metabolic remodeling" to provide sufficient ATP to maintain cell survival and to promote rapid growth. In colorectal cancer cells, ATP is produced by mitochondrial oxidative phosphorylation and by substantially elevated cytoplasmic glucose fermentation (i.e., the Warburg effect). Glucose transporter 1 (GLUT1) expression is significantly increased in colorectal cancer cells, and GLUT1 inhibitors block glucose uptake and hence glycolysis crucial for cancer cell growth. In addition to ATP, these metabolic pathways also provide macromolecule building blocks and signaling molecules required for tumor growth. In this study, we identify a diaminobutoxy-substituted isoflavonoid (DBI-1) that inhibits mitochondrial complex I and deprives rapidly growing cancer cells of energy needed for growth. DBI-1 and the GLUT1 inhibitor, BAY-876, synergistically inhibit colorectal cancer cell growth in vitro and in vivo. This study suggests that an electron transport chain inhibitor (i.e., DBI-1) and a glucose transport inhibitor, (i.e., BAY-876) are potentially effective combination for colorectal cancer treatment.
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Neoplasias do Colo , Humanos , Trifosfato de Adenosina , Linhagem Celular Tumoral , Transformação Celular Neoplásica , Neoplasias do Colo/tratamento farmacológico , Glucose , Transportador de Glucose Tipo 1/genética , Glicólise , Pirazóis , Quinolinas , Fatores de TranscriçãoRESUMO
Oxonitridosilicates, in which O atoms in SiO4 are partially substituted by N atoms, are proposed to improve optical anisotropies of silicates as UV NLO materials. The optical properties calculation showed that the heteroleptic SiOxN4-x (x = 1-3) tetrahedra have strong polarizability anisotropy and large hyperpolarizability. Accordingly, nine noncentrosymmetric (NCS) oxonitridosilicate crystals collected in the inorganic crystal structural database (ICSD) are evaluated by using the first principles method. Finally, Si2N2O and LiSiON are screened out owing to wide band gaps (6.49 and 6.95 eV), large birefringences (0.102 and 0.060 at 1064 nm), and large SHG coefficients (3.3 and 2.2 times that of d36(KDP)). More importantly, the cation selection and structural characteristics that are beneficial for enhancing the band gap and birefringence are identified. This study provides a novel strategy to design and find UV NLO crystals.
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Developing effective treatments for colorectal cancers through combinations of small-molecule approaches and immunotherapies present intriguing possibilities for managing these otherwise intractable cancers. During a broad-based, screening effort against multiple colorectal cancer cell lines, we identified indole-substituted quinolines (ISQ), such as N7,N7 -dimethyl-3-(1-methyl-1H-indol-3-yl)quinoline-2,7-diamine (ISQ-1), as potent in vitro inhibitors of several cancer cell lines. We found that ISQ-1 inhibited Wnt signaling, a main driver in the pathway governing colorectal cancer development, and ISQ-1 also activated adenosine monophosphate kinase (AMPK), a cellular energy-homeostasis master regulator. We explored the effect of ISQs on cell metabolism. Seahorse assays measuring oxygen consumption rate (OCR) indicated that ISQ-1 inhibited complex I (i.e., NADH ubiquinone oxidoreductase) in the mitochondrial, electron transport chain (ETC). In addition, ISQ-1 treatment showed remarkable synergistic depletion of oncogenic c-Myc protein level in vitro and induced strong tumor remission in vivo when administered together with BI2536, a polo-like kinase-1 (Plk1) inhibitor. These studies point toward the potential value of dual drug therapies targeting the ETC and Plk-1 for the treatment of c-Myc-driven cancers.
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Amodiaquina/análogos & derivados , Proteínas de Ciclo Celular/antagonistas & inibidores , Neoplasias Colorretais/tratamento farmacológico , Sinergismo Farmacológico , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-myc/metabolismo , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Pteridinas/farmacologia , Amodiaquina/farmacologia , Animais , Apoptose , Proliferação de Células , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Feminino , Humanos , Masculino , Camundongos , Camundongos Nus , Proteínas Proto-Oncogênicas c-myc/genética , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto , Quinase 1 Polo-LikeRESUMO
A flexible one-pot strategy for fabricating a 3D network of nitrogen-doped (N-doped) carbon ultrathin nanosheets with closely packed mesopores (N-MCN) via an in situ template method is reported in this research. The self-assembly soluble salts (NaCl and Na2SiO3) serve as hierarchical templates and support the formation of a 3D glucose-urea complex. The organic complex is heat-treated to obtain a 3D N-doped carbon network constructed by mesoporous nanosheets. Especially, both the mesoporous structure and doping content can be easily tuned by adjusting the ratio of raw materials. The large specific surface area and closely packed mesopores facilitate the lithium ion intercalation/deintercalation accordingly. Besides, the nitrogen content improves the lithium storage ability and capacitive properties. Due to the synergistic effect of hierarchical structure and heteroatom composition, the 3D N-MCN shows excellent characteristics as the electrode of a lithium ion battery and supercapacitor, such as ultrahigh reversible storage capacity (1222 mAh g(-1) at 0.1 A g(-1)), stable long cycle performance at high current density (600 cycles at 2 A g(-1)), and high capacitive properties (225 F g(-1) at 1 A g(-1) and 163 F g(-1) at 50 A g(-1)).
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Sluggish surface reaction kinetics hinders the power density of Li-ion battery. Thus, various surface modification techniques have been applied to enhance the electronic/ionic transfer kinetics. However, it is challenging to obtain a continuous and uniform surface modification layer on the prime particles with structure integration at the interface. Instead of classic physical-adsorption/deposition techniques, we propose a novel chemical-adsorption strategy to synthesize double-shell modified lithium-rich layered cathodes with enhanced mass transfer kinetics. On the basis of experimental measurement and first-principles calculation, MoO2S2 ions are proved to joint the layered phase via chemical bonding. Specifically, the Mo-O or Mo-S bonds can flexibly rotate to bond with the cations in the layered phase, leading to the good compatibility between the thiomolybdate adsorption layer and layered cathode. Followed by annealing treatment, the lithium-excess-spinel inner shell forms under the thiomolybdate adsorption layer and functions as favorable pathways for lithium and electron. Meanwhile, the nanothick MoO3-x(SO4)x outer shell protects the transition metal from dissolution and restrains electrolyte decomposition. The double-shell modified sample delivers an enhanced discharge capacity almost twice as much as that of the unmodified one at 1 A g(-1) after 100 cycles, demonstrating the superiority of the surface modification based on chemical adsorption.
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Uniform transition metal sulfide deposition on a smooth TiO2 surface to form a coating structure is a well-known challenge, caused mainly due to their poor affinities. Herein, we report a facile strategy for fabricating mesoporous 3D few-layered (<4 layers) MoS2 coated TiO2 nanosheet core-shell nanocomposites (denoted as 3D FL-MoS2@TiO2) by a novel two-step method using a smooth TiO2 nanosheet as a template and glucose as a binder. The core-shell structure has been systematically examined and corroborated by transmission electron microscopy, scanning transmission electron microscopy, and X-ray photoelectron spectroscopy analyses. It is found that the resultant 3D FL-MoS2@TiO2 as a lithium-ion battery anode delivers an outstanding high-rate capability with an excellent cycling performance, relating to the unique structure of 3D FL-MoS2@TiO2. The 3D uniform coverage of few-layered (<4 layers) MoS2 onto the TiO2 can remarkably enhance the structure stability and effectively shortens the transfer paths of both lithium ions and electrons, while the strong synergistic effect between MoS2 and TiO2 can significantly facilitate the transport of ions and electrons across the interfaces, especially in the high-rate charge-discharge process. Moreover, the facile fabrication strategy can be easily extended to design other oxide/carbon-sulfide/oxide core-shell materials for extensive applications.
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Poor rate capability and cycling performance are the major barriers to the application of lithium rich layered oxides (LLOs) as the next generation cathodes materials for lithium-ion batteries. In this paper, a novel surface double phase network modification has been applied to enhance the rate property of Li1.2Co0.13Ni0.13Mn0.54O2 (LR) via flexible electrostatic heterocoagulation and thermal treatment. The template action of multiwalled carbon nanotubes (MWCNTs) network on LR clusters results in the spinel phase network formation at the interface between the LR and MWCNTs. The phase transformation process from layered component toward spinel phase is identified through the detailed investigation of the interface using high-resolution transmission electron microscopy, fast Fourier transformation, and the detailed analysis on the transformation of simulated diffraction patterns. The double phases stretch two sets of networks with both fine Li ion and electron conductivity onto and within the clusters of LR, lowering the surface resistance, reducing the electrochemical polarization, and as a result, significantly enhancing the rate capability of LR. The double phase network modification, combining MWCNT coagulation and spinel phase modification, has profound potential in accelerating kinetics for LLOs.