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1.
Blood ; 140(16): 1790-1802, 2022 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-35981465

RESUMO

The bispecific T-cell engager (BiTE) blinatumomab against CD19 and CD3 has emerged as the most successful bispecific antibody (bsAb) to date; however, a significant proportion of patients do not respond to the treatments or eventually experience relapse after an initial response, and the recurrence rate increases significantly due to escape or downregulation of the CD19 antigen. To enhance antitumor efficacy and overcome potential immune escape, we developed a novel approach to design a CD19/CD22/CD3 trispecific antibody (tsAb) by site-specifically fusing anti-CD19 scFv (FMC63) and anti-CD22 nanobody (Nb25) to the defined sites of the CD3 antigen-binding fragment (Fab, SP34). This strategy allows for the optimal formation of immune synapses mediated by CD19/CD22/CD3 between target cells and T cells. Optimized tsAb can be superior for inducing T-cell-specific cytotoxicity and cytokine production against CD19+ and/or CD22+ tumor cells compared to other tsAb formats, and demonstrated significantly enhanced antitumor efficacy and the ability to overcome immune escape compared with the corresponding bsAbs alone or in combination, as well as with blinatumomab. In addition, tsAb treatment can lead to the long-term elimination of primary B-ALL patient samples in the PDX model and significantly prolong survival. This novel approach provides unique insight into the structural optimization of T-cell-redirected multispecific antibodies using site-specific recombination, and may be broadly applicable to heterogeneous and resistant tumor populations as well as solid tumors.


Assuntos
Anticorpos Biespecíficos , Linfoma de Burkitt , Linfoma de Células B , Leucemia-Linfoma Linfoblástico de Células Precursoras , Humanos , Antígenos CD19 , Complexo CD3 , Recidiva Local de Neoplasia/tratamento farmacológico , Anticorpos Biespecíficos/farmacologia , Anticorpos Biespecíficos/uso terapêutico , Linfoma de Células B/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Linfoma de Burkitt/tratamento farmacológico , Citocinas , Lectina 2 Semelhante a Ig de Ligação ao Ácido Siálico
2.
Cell Commun Signal ; 22(1): 74, 2024 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-38279145

RESUMO

The tumor microenvironment (TME) constitutes a complex microenvironment comprising a diverse array of immune cells and stromal components. Within this intricate context, tumor-associated macrophages (TAMs) exhibit notable spatial heterogeneity. This heterogeneity contributes to various facets of tumor behavior, including immune response modulation, angiogenesis, tissue remodeling, and metastatic potential. This review summarizes the spatial distribution of macrophages in both the physiological environment and the TME. Moreover, this paper explores the intricate interactions between TAMs and diverse immune cell populations (T cells, dendritic cells, neutrophils, natural killer cells, and other immune cells) within the TME. These bidirectional exchanges form a complex network of immune interactions that influence tumor immune surveillance and evasion strategies. Investigating TAM heterogeneity and its intricate interactions with different immune cell populations offers potential avenues for therapeutic interventions. Additionally, this paper discusses therapeutic strategies targeting macrophages, aiming to uncover novel approaches for immunotherapy. Video Abstract.


Assuntos
Neoplasias , Microambiente Tumoral , Humanos , Macrófagos , Macrófagos Associados a Tumor , Imunoterapia , Células Matadoras Naturais
3.
Environ Toxicol ; 39(6): 3481-3499, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38456329

RESUMO

CONTEXT: Qi-dan-dihuang decoction (QDD) has been used to treat diabetic kidney disease (DKD), but the underlying mechanisms are poorly understood. OBJECTIVE: This study reveals the mechanism by which QDD ameliorates DKD. MATERIALS AND METHODS: The compounds in QDD were identified by high-performance liquid chromatography and quadrupole-time-of-flight tandem mass spectrometry (HPLC-Q-TOF-MS). Key targets and signaling pathways were screened through bioinformatics. Nondiabetic Lepr db/m mice were used as control group, while Lepr db/db mice were divided into model group, dapagliflozin group, 1% QDD-low (QDD-L), and 2% QDD-high (QDD-H) group. After 12 weeks of administration, 24 h urinary protein, serum creatinine, and blood urea nitrogen levels were detected. Kidney tissues damage and fibrosis were evaluated by pathological staining. In addition, 30 mmol/L glucose-treated HK-2 and NRK-52E cells to induce DKD model. Cell activity and migration capacity as well as protein expression levels were evaluated. RESULTS: A total of 46 key target genes were identified. Functional enrichment analyses showed that key target genes were significantly enriched in the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) and mitogen-activated protein kinase (MAPK) signaling pathways. In addition, in vivo and in vitro experiments confirmed that QDD ameliorated renal fibrosis in diabetic mice by resolving inflammation and inhibiting the epithelial-mesenchymal transition (EMT) via the p38MAPK and AKT-mammalian target of rapamycin (mTOR) pathways. DISCUSSION AND CONCLUSION: QDD inhibits EMT and the inflammatory response through the p38MAPK and AKT/mTOR signaling pathways, thereby playing a protective role in renal fibrosis in DKD.


Assuntos
Diabetes Mellitus Experimental , Nefropatias Diabéticas , Medicamentos de Ervas Chinesas , Transdução de Sinais , Animais , Humanos , Masculino , Camundongos , Ratos , Linhagem Celular , Diabetes Mellitus Experimental/tratamento farmacológico , Nefropatias Diabéticas/tratamento farmacológico , Nefropatias Diabéticas/patologia , Medicamentos de Ervas Chinesas/farmacologia , Fibrose , Rim/efeitos dos fármacos , Rim/patologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo
4.
Phys Rev Lett ; 131(1): 016202, 2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37478437

RESUMO

For the semiconductors of atomic length scales, even one atom layer difference could modify crystal symmetry and lead to a significant change in electronic structure, which is essential for modern electronics. However, the experimental exploration of such effect has not been achieved due to challenges in sample fabrication and characterization with atomic-scale precision. Here, we report the discovery of crystal symmetry alternation induced band-gap oscillation in atomically thin PbTe films by scanning tunneling microscopy. As the thickness of PbTe films is reduced from an 18- to 2-atomic layer, the band-gap size not only expands from 0.19 eV to 1.06 eV by 5.6 fold, but also exhibits an even-odd-layer oscillation, which is attributed to the alternating crystal symmetries between P4/mmm and P4/nmm. Our work sheds new light on electronic structure engineering of semiconductors at atomic scale for next-generation nanoelectronics.

5.
Phytother Res ; 37(8): 3195-3210, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37013717

RESUMO

Elevations in circling branched-chain amino acids (BCAAs) levels associated with insulin resistance and type 2 diabetes mellitus (T2DM). Morus alba L. water extracts (MLE) show hypoglycemic function, but the precise mechanism remains obscure. This study is designed to investigate the association of the antidiabetes effect of MLE with the BCAAs co-metabolism modulated by host and gut microbiota. Tissue-specific expressions of BCAA-catabolizing enzymes were detected by RT-PCR and western blot, respectively. The components of the intestinal microflora were analyzed by high-throughput 16S rRNA gene sequencing. The results showed that MLE administration improved blood glucose and insulin level, decreased inflammatory cytokines expression, and lowered serum and feces BCAAs levels. Furthermore, MLE reversed the abundance changes of the bacterial genera correlated with serum and feces BCAAs, such as Anaerovorax, Bilophila, Blautia, Colidextribacter, Dubosiella, Intestinimonas, Lachnoclostridium, Lachnospiraceae_NK4A136, Oscillibacter, and Roseburia. Functionality prediction indicated that MLE potentially inhibited bacterial BCAAs biosynthesis, and promoted the tissue-specific expression of BCAAs catabolic enzyme. More importantly, MLE had obvious impacts on BCAA catabolism in germ-free-mimic T2DM mice. Those results indicated that MLE improving T2DM-related biochemical abnormalities is associated with not only gut microbiota modification but also the tissue-specific expression of BCAAs catabolic enzyme.


Assuntos
Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Resistência à Insulina , Morus , Camundongos , Animais , Diabetes Mellitus Tipo 2/metabolismo , Morus/química , RNA Ribossômico 16S/análise , Aminoácidos de Cadeia Ramificada/análise , Aminoácidos de Cadeia Ramificada/metabolismo , Folhas de Planta/química
6.
Int J Mol Sci ; 24(12)2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37373296

RESUMO

Phosphorylation of the serine 139 of the histone variant H2AX (γH2AX) is a DNA damage marker that regulates DNA damage response and various diseases. However, whether γH2AX is involved in neuropathic pain is still unclear. We found the expression of γH2AX and H2AX decreased in mice dorsal root ganglion (DRG) after spared nerve injury (SNI). Ataxia telangiectasia mutated (ATM), which promotes γH2AX, was also down-regulated in DRG after peripheral nerve injury. ATM inhibitor KU55933 decreased the level of γH2AX in ND7/23 cells. The intrathecal injection of KU55933 down-regulated DRG γH2AX expression and significantly induced mechanical allodynia and thermal hyperalgesia in a dose-dependent manner. The inhibition of ATM by siRNA could also decrease the pain threshold. The inhibition of dephosphorylation of γH2AX by protein phosphatase 2A (PP2A) siRNA partially suppressed the down-regulation of γH2AX after SNI and relieved pain behavior. Further exploration of the mechanism revealed that inhibiting ATM by KU55933 up-regulated extracellular-signal regulated kinase (ERK) phosphorylation and down-regulated potassium ion channel genes, such as potassium voltage-gated channel subfamily Q member 2 (Kcnq2) and potassium voltage-gated channel subfamily D member 2 (Kcnd2) in vivo, and KU559333 enhanced sensory neuron excitability in vitro. These preliminary findings imply that the down-regulation of γH2AX may contribute to neuropathic pain.


Assuntos
Neuralgia , Traumatismos dos Nervos Periféricos , Animais , Camundongos , Gânglios Espinais/metabolismo , Hiperalgesia/genética , Hiperalgesia/metabolismo , Neuralgia/etiologia , Neuralgia/metabolismo , Traumatismos dos Nervos Periféricos/metabolismo , Potássio/metabolismo , RNA Interferente Pequeno/metabolismo , Células Receptoras Sensoriais/metabolismo , Canais de Potássio Shal/metabolismo
7.
BMC Musculoskelet Disord ; 23(1): 521, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35650582

RESUMO

OBJECTIVE: The application of double plating in olecranon fractures is becoming increasingly widespread. There is no research comparing this technique with traditional tension band wiring (TBW) and the single plate technique. The purpose of this study was to compare the efficacy of three fixation techniques in olecranon fractures. MATERIALS AND METHODS: From March 2016 to May 2020, we collected the clinical data of 95 patients with olecranon fractures who underwent surgical treatment. Thirty-five patients received TBW surgery (TBW Group), 32 patients received a 3.5 mm locking compression plate (LCP, 3.5 mm LCP Group), and 28 patients received double mini-locking plate treatment (DP Group). The operation time, fracture union time, time of return to work, range of motion (ROM), soft tissue stimulation to remove internal fixation, and patient-related functional results (the Weseley score, Mayo Elbow Performance Score [MEPS], and Disabilities of Arm, Shoulder and Hand Score [DASH]) were recorded. The clinical results and complications of the three internal fixation techniques were compared. RESULTS: The average follow-up time was 15.011.82 months (12-18 months). All patients' fractures healed by first intention. There were no statistically significant differences in the operation time, fracture union time, ROM, Weseley score, MEPS or DASH scores of the three groups of patients. The postoperative return time for patients in the TBW group was 10.002.15 weeks, the 3.5 mm LCP group was 9.561.93 weeks, and the DP group was 8.432.38 weeks (P = 0.014); 12 patients in the TBW group required removal of plant due to soft tissue stimulation, the 3.5 mm LCP group had 8 cases, and the DP group had 2 cases (P = 0.038). CONCLUSION: The postoperative clinical results and elbow joint function of patients with olecranon fractures fixed by tension band wiring, 3.5 mm LCP and double mini-locking plate are similar, which indicates that double-plate technology can be used as an alternative to the two groups of traditional techniques. In addition, double-plate technology also helps patients return to work earlier and has a lower incidence of soft tissue stimulation.


Assuntos
Fraturas Ósseas , Olécrano , Fraturas da Ulna , Fios Ortopédicos , Fixação Interna de Fraturas/efeitos adversos , Fixação Interna de Fraturas/métodos , Humanos , Olécrano/diagnóstico por imagem , Olécrano/cirurgia , Estudos Retrospectivos , Fraturas da Ulna/diagnóstico por imagem , Fraturas da Ulna/cirurgia
8.
Phytother Res ; 36(3): 1241-1257, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35129235

RESUMO

Gut microbiota plays a key role in the pathophysiology of type 2 diabetes mellitus (T2D). Mulberry leaf has a hypoglycemic effect, but the potential mechanism is not fully understood. This study aimed to explore the influences and potential mechanisms of mulberry leaf water extract (MLWE) intervention on mice with T2D induced through a high-fat and high-sucrose diet combined with streptozotocin by the combination of fecal metabolomics and gut microbiota analysis. Results showed that MLWE could decrease fasting blood glucose and body weight while ameliorating lipid profiles, insulin resistance, liver inflammation, and the accumulation of lipid droplets in T2D mice. MLWE could reverse the abundances of the phyla Actinobacteria and Bacteroidetes and the ratio of Firmicutes/Bacteroidetes, and increase the abundances of the phyla Cyanobacteria and Epsilonbacteraeota in the feces of T2D mice. The abundances of genera Alloprevotella, Parabacteroides, Muribaculaceae, and Romboutsia in the feces of T2D mice could be reversed, while Oscillatoriales_cyanobacterium and Gastranaerophilales could be reinforced by MLWE supplementation. The levels of nine metabolites in the feces of T2D mice were improved, among which glycine, Phe-Pro, urocanic acid, phylloquinone, and lactate were correlated with Romboutsia and Gastranaerophilales. Taken together, we conclude that MLWE can effectively alleviate T2D by mediating the host-microbial metabolic axis.


Assuntos
Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Morus , Animais , Dieta Hiperlipídica/efeitos adversos , Fezes , Metaboloma , Camundongos , Estreptozocina , Sacarose , Água
9.
Biomed Chromatogr ; 35(3): e4998, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33037660

RESUMO

Isoliquiritigenin (ILG) and isoliquiritin (ILQ), two kinds of major flavonoids in licorice, are biological active substances with antioxidant, anti-inflammatory, and tumor-suppressive effects. However, their in vivo metabolites, possible material basis of this two licorice chalcones for the treatment of diseases, have not been studied completely. To determine the metabolism of ILG and ILQ, after oral administration of 100 mg/kg/day of these compounds for consecutive 8 days, the metabolites of these two licorice chalcones in mice plasma, urine, feces, and bile were determined using liquid chromatography coupled with quadrupole/time-of-flight mass spectrometry in this study. The structures of those metabolites were tentatively identified according to their fragment pathways, accurate masses, characteristic product ions, metabolism law, and reference standards-matching. As a result, a total of 25 and 29 metabolites of ILG and ILQ were identified, respectively. Seven main metabolic pathways, oxidation and reduction, deglycosylation and glycosylation, dehydroxylation and hydroxylation, demethoxylation and methoxylation, acetylation, glucuronidation, and sulfation, were summarized to tentatively explain how the metabolites were biologically transformed. These results provide the important information on the metabolism of ILG and ILQ, which may be helpful for the further research of their pharmacological mechanism.


Assuntos
Chalcona/análogos & derivados , Chalconas/análise , Cromatografia Líquida/métodos , Glucosídeos/análise , Espectrometria de Massas em Tandem/métodos , Administração Oral , Animais , Bile/química , Chalcona/administração & dosagem , Chalcona/análise , Chalcona/química , Chalcona/farmacocinética , Chalconas/administração & dosagem , Chalconas/química , Chalconas/farmacocinética , Fezes/química , Glucosídeos/administração & dosagem , Glucosídeos/química , Glucosídeos/farmacocinética , Glycyrrhiza , Camundongos , Camundongos Endogâmicos C57BL
10.
Phys Rev Lett ; 122(20): 206402, 2019 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-31172745

RESUMO

Two-dimensional (2D) quasiparticle standing waves originate from the interference of coherent quantum states and are usually created by the scattering off edges, atomic steps, or adatoms that induce large potential barriers. We report standing waves close to the valence band maximum (E_{V}), confined by electrically neutral domain walls of newly discovered ferroelectric SnTe monolayers, as revealed by spatially resolved scanning tunneling spectroscopy. Ab initio calculations show that this novel confinement arises from the polarization lifted hole valley degeneracy and a ∼90° rotation of the Brillouin zones that render holes' momentum mismatched across neighboring domains. These results show a potential for polarization-tuned valleytronics in 2D ferroelectrics.

11.
Biosci Biotechnol Biochem ; 83(4): 666-674, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30585123

RESUMO

Asparagus (Asparagus officinalis) has several traits that make it a useful model for cytogenetic studies, however, few studies of the meiosis process have been made in asparagus. Here, we present in detail an atlas of male meiosis in asparagus, from preleptotene to telophase II. The meiosis process in asparagus is largely similar to those of the well-characterized model plants Arabidopsis thaliana, Zea mays, and Oryza sativa. However, most asparagus prophase I meiotic chromosomes show a strongly aggregated morphology, and this phenotype persists through the pachytene stage, highlighting a property in the control of chromosome migration and distribution in asparagus. Further, we observed no obvious banding of autofluorescent dots between divided nuclei of asparagus meiocytes, as one would expect in Arabidopsis. This description of wild-type asparagus meiosis will serve as a reference for the analyses of meiotic mutants, as well as for comparative studies among difference species. Abbreviations: DAPI: 4',6-diamidino-2-phenylindole; FISH: fluorescence in situ hybridization; PBS: phosphate-buffered saline; PMC: pollen mother cell; SEM: Scanning Electron Microscope.


Assuntos
Asparagus/ultraestrutura , Cromossomos de Plantas/ultraestrutura , Meiose , Células Vegetais/ultraestrutura , Pólen/ultraestrutura , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/ultraestrutura , Asparagus/genética , Asparagus/crescimento & desenvolvimento , Núcleo Celular/metabolismo , Núcleo Celular/ultraestrutura , Cromossomos de Plantas/química , Flores/genética , Flores/crescimento & desenvolvimento , Flores/ultraestrutura , Hibridização in Situ Fluorescente , Microscopia Eletrônica de Varredura , Células Vegetais/metabolismo , Pólen/genética , Pólen/crescimento & desenvolvimento
12.
Anal Chem ; 89(5): 3146-3153, 2017 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-28192986

RESUMO

Secondary metabolites are usually the bioactive components of medicinal plants. The difference in the secondary metabolisms of closely related plant species and their hybrids has rarely been addressed. In this study, we conducted a holistic secondary metabolomics analysis of three medicinal Glycyrrhiza species (G. uralensis, G. glabra, and G. inflata), which are used as the popular herbal medicine licorice. The Glycyrrhiza species (genotype) for 95 batches of samples were identified by DNA barcodes of the internal transcribed spacer and trnV-ndhC regions, and the chemotypes were revealed by LC/UV- or LC/MS/MS-based quantitative analysis of 151 bioactive secondary metabolites, including 17 flavonoid glycosides, 24 saponins, and 110 free phenolic compounds. These compounds represented key products in the biosynthetic pathways of licorice. For the 76 homozygous samples, the three Glycyrrhiza species showed significant biosynthetic preferences, especially in coumarins, chalcones, isoflavanes, and flavonols. In total, 27 species-specific chemical markers were discovered. The 19 hybrid samples indicated that hybridization could remarkably alter the chemical composition and that the male parent contributed more to the offspring than the female parent did. This is hitherto the largest-scale targeted secondary metabolomics study of medicinal plants and the first report on uniparental inheritance in plant secondary metabolism. The results are valuable for biosynthesis, inheritance, and quality control studies of licorice and other medicinal plants.


Assuntos
Glicosídeos/análise , Glycyrrhiza/química , Metabolômica , Fenóis/análise , Plantas Medicinais/química , Saponinas/análise , Cromatografia Líquida de Alta Pressão , Código de Barras de DNA Taxonômico , Flavonoides/química , Genótipo , Glicosídeos/metabolismo , Glycyrrhiza/genética , Glycyrrhiza/metabolismo , Fenóis/metabolismo , Plantas Medicinais/genética , Plantas Medicinais/metabolismo , Análise de Componente Principal , Saponinas/metabolismo , Espectrofotometria Ultravioleta , Espectrometria de Massas em Tandem
13.
Toxicol Appl Pharmacol ; 326: 25-33, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28416456

RESUMO

Licorice (Glycyrrhiza uralensis Fisch.) possesses significant anti-cancer activities, but the active ingredients and underlying mechanisms have not been revealed. By screening the cytotoxic activities of 122 licorice compounds against SW480 human colorectal adenocarcinoma cells, we found that licoricidin (LCD) inhibited SW480 cell viability with an IC50 value of 7.2µM. Further studies indicated that LCD significantly induced G1/S cell cycle arrest and apoptosis in SW480 cells, accompanied by inhibition of cyclins/CDK1 expression and activation of caspase-dependent pro-apoptotic signaling. Meanwhile, LCD promoted autophagy in SW480 cells, and activated AMPK signaling and inhibited Akt/mTOR pathway. Overexpression of a dominant-negative AMPKα2 abolished LCD-induced inhibition of Akt/mTOR, autophagic and pro-apoptotic signaling pathways, and significantly reversed loss of cell viability, suggesting activation of AMPK is essential for the anti-cancer activity of LCD. In vivo anti-tumor experiments indicated that LCD (20mg/kg, i.p.) significantly inhibited the growth of SW480 xenografts in nude mice with an inhibitory rate of 43.5%. In addition, we obtained the glycosylated product LCDG by microbial transformation, and found that glycosylation slightly enhanced the in vivo anti-cancer activities of LCD. This study indicates that LCD could inhibit SW480 cells by inducing cycle arrest, apoptosis and autophagy, and is a potential chemopreventive or chemotherapeutic agent against colorectal cancer.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Benzopiranos/farmacologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/tratamento farmacológico , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Relação Dose-Resposta a Droga , Glicosilação , Humanos , Concentração Inibidora 50 , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Fatores de Tempo , Transfecção , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Bioorg Med Chem ; 25(20): 5522-5530, 2017 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-28835349

RESUMO

Glycyrrhiza inflata (licorice) has been used to treat liver diseases for a long history. However, the bioactive compounds are still not clear. In this work, 77 compounds, including 9 new ones, were isolated from the EtOAc extract of the roots and rhizomes of G. inflata. The Nrf2 activation activities of all compounds were screened using ARE-luciferase reporter assay on HepG2C8 cells. The results indicated a number of chalcones were potent Nrf2 activators, including 11 (licochalcone A, 4.07-fold), 12 (licochalcone B, 5.17-fold), and 19 (echinatin, 4.09-fold). Further studies indicated that 11, 12 and 19 remarkably attenuated CCl4-induced acute liver injury in mice (10 or 50mg/kg, 7days, ig.). These compounds could be promising hepatoprotective natural agents.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Glycyrrhiza/química , Fator 2 Relacionado a NF-E2/metabolismo , Extratos Vegetais/farmacologia , Administração Oral , Animais , Tetracloreto de Carbono , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Células Hep G2 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos ICR , Estrutura Molecular , Extratos Vegetais/administração & dosagem , Extratos Vegetais/isolamento & purificação , Raízes de Plantas/química , Ratos , Ratos Sprague-Dawley
15.
J Nat Prod ; 80(2): 334-346, 2017 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-28140583

RESUMO

In an attempt to discover bioactive agents from the herbal medicine Glycyrrhiza glabra (widely known as licorice), 11 new phenolic compounds, glycybridins A-K (1-11), along with 47 known phenolics (12-58) were isolated. Their structures were elucidated on the basis of extensive NMR and MS analyses as well as experimental and computed ECD data. According to the clinical therapeutic effects of licorice, enzyme or cell-based bioactivity screenings of 1-58 were conducted. A number of compounds significantly activate Nrf2, inhibit tyrosinase or PTP1B, inhibit LPS-induced NO production and NF-κB transcription, and inhibit the proliferation of human cancer cells (HepG2, SW480, A549, MCF7). Glycybridin D (4) showed moderate cytotoxic activities against the four cancer cell lines, with IC50 values ranging from 4.6 to 6.6 µM. Further studies indicated that 4 (10 mg/kg, ip) decreased tumor mass by 39.7% on an A549 human lung carcinoma xenograft mice model, but showed little toxicity.


Assuntos
Glycyrrhiza/química , Fenóis/isolamento & purificação , Fenóis/farmacologia , Plantas Medicinais/química , Animais , Antioxidantes/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Células Hep G2 , Humanos , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Camundongos , Estrutura Molecular , Monofenol Mono-Oxigenase/antagonistas & inibidores , NF-kappa B/antagonistas & inibidores , Óxido Nítrico/biossíntese , Fenóis/química , Raízes de Plantas/química , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Rizoma/química
16.
Anal Chem ; 88(1): 703-10, 2016 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-26606385

RESUMO

To fully understand the chemical diversity of an herbal medicine is challenging. In this work, we describe a new approach to globally profile and discover novel compounds from an herbal extract using multiple neutral loss/precursor ion scanning combined with substructure recognition and statistical analysis. Turmeric (the rhizomes of Curcuma longa L.) was used as an example. This approach consists of three steps: (i) multiple neutral loss/precursor ion scanning to obtain substructure information; (ii) targeted identification of new compounds by extracted ion current and substructure recognition; and (iii) untargeted identification using total ion current and multivariate statistical analysis to discover novel structures. Using this approach, 846 terpecurcumins (terpene-conjugated curcuminoids) were discovered from turmeric, including a number of potentially novel compounds. Furthermore, two unprecedented compounds (terpecurcumins X and Y) were purified, and their structures were identified by NMR spectroscopy. This study extended the application of mass spectrometry to global profiling of natural products in herbal medicines and could help chemists to rapidly discover novel compounds from a complex matrix.


Assuntos
Curcuma/química , Curcumina/química , Terpenos/química , Cromatografia Líquida de Alta Pressão , Curcumina/análogos & derivados , Curcumina/isolamento & purificação , Interpretação Estatística de Dados , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular
17.
Phys Rev Lett ; 116(15): 157001, 2016 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-27127981

RESUMO

We report on the emergence of two disconnected superconducting domes in alkali-metal potassium- (K-)doped FeSe ultrathin films grown on graphitized SiC(0001). The superconductivity exhibits hypersensitivity to K dosage in the lower-T_{c} dome, whereas in the heavily electron-doped higher-T_{c} dome it becomes spatially homogeneous and robust against disorder, supportive of a conventional Cooper-pairing mechanism. Furthermore, the heavily K-doped multilayer FeSe films all reveal a large superconducting gap of ∼14 meV, irrespective of film thickness, verifying the higher-T_{c} superconductivity only in the topmost FeSe layer. The unusual finding of a double-dome superconducting phase is a step towards the mechanistic understanding of superconductivity in FeSe-derived superconductors.

18.
J Nat Prod ; 79(2): 281-92, 2016 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-26841168

RESUMO

Traditional herbal medicines have been reported to possess significant bioactivities. In this investigation, a combined strategy using both phytochemical and biological approaches was conducted to discern the effective components of licorice, a widely used herbal medicine. Altogether, 122 compounds (1-122), including six new structures (1-6), were isolated and identified from the roots and rhizomes of Glycyrrhiza uralensis (licorice). These compounds were then screened using 11 cell- and enzyme-based bioassay methods, including Nrf2 activation, NO inhibition, NF-κB inhibition, H1N1 virus inhibition, cytotoxicity for cancer cells (HepG2, SW480, A549, MCF7), PTP1B inhibition, tyrosinase inhibition, and AChE inhibition. A number of bioactive compounds, particularly isoprenylated phenolics, were found for the first time. Echinatin (7), a potent Nrf2 activator, was selected as an example for further biological work. It attenuated CCl4-induced liver damage in mice (5 or 10 mg/kg, ip) and thus is responsible, at least in part, for the hepatoprotective activity of licorice.


Assuntos
Medicamentos de Ervas Chinesas , Glycyrrhiza uralensis , Glycyrrhiza , Fígado , Medicina Tradicional , Plantas Medicinais , Animais , Humanos , Camundongos , Acetilcolinesterase , Tetracloreto de Carbono/farmacologia , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Medicamentos de Ervas Chinesas/farmacologia , Glycyrrhiza/química , Glycyrrhiza uralensis/química , Proteínas Ligadas por GPI/antagonistas & inibidores , Células Hep G2 , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Macrófagos/efeitos dos fármacos , Células MCF-7 , Estrutura Molecular , Monofenol Mono-Oxigenase/antagonistas & inibidores , NF-kappa B/antagonistas & inibidores , Óxido Nítrico/biossíntese , Ressonância Magnética Nuclear Biomolecular , Raízes de Plantas/química , Plantas Medicinais/química , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Alcaloides de Pirrolizidina/química , Alcaloides de Pirrolizidina/isolamento & purificação , Alcaloides de Pirrolizidina/farmacologia , Rizoma/química , Relação Estrutura-Atividade
19.
Phys Rev Lett ; 114(17): 176602, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25978246

RESUMO

Scanning tunneling microscopy and spectroscopy have been used to investigate the femtosecond dynamics of Dirac fermions in the topological insulator Bi2Se3 ultrathin films. At the two-dimensional limit, bulk electrons become quantized and the quantization can be controlled by the film thickness at a single quintuple layer level. By studying the spatial decay of standing waves (quasiparticle interference patterns) off steps, we measure directly the energy and film thickness dependence of the phase relaxation length lϕ and inelastic scattering lifetime τ of topological surface-state electrons. We find that τ exhibits a remarkable (E - EF)(-2) energy dependence and increases with film thickness. We show that the features revealed are typical for electron-electron scattering between surface and bulk states.

20.
Phys Rev Lett ; 115(23): 237002, 2015 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-26684137

RESUMO

Understanding the mechanism of high transition temperature (T{c}) superconductivity in cuprates has been hindered by the apparent complexity of their multilayered crystal structure. Using a cryogenic scanning tunneling microscopy (STM), we report on layer-by-layer probing of the electronic structures of all ingredient planes (BiO, SrO, CuO{2}) of Bi{2}Sr{2}CaCu_2}O{8+δ} superconductor prepared by argon-ion bombardment and annealing technique. We show that the well-known pseudogap (PG) feature observed by STM is inherently a property of the BiO planes and thus irrelevant directly to Cooper pairing. The SrO planes exhibit an unexpected van Hove singularity near the Fermi level, while the CuO{2} planes are exclusively characterized by a smaller gap inside the PG. The small gap becomes invisible near T{c}, which we identify as the superconducting gap. The above results constitute severe constraints on any microscopic model for high T{c} superconductivity in cuprates.

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