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1.
J Agric Food Chem ; 71(41): 14870-14889, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37800982

RESUMO

Dendrobium officinale, a plant in the Orchidaceae family, has been used in traditional Chinese medicine for thousands of years. Sweet and slightly cold in nature, it can invigorate the stomach, promote fluid production, nourish Yin, and dissipate heat. Over the past decade, more than 60 compounds have been derived from D. officinale, including flavonoids, bibenzyl, and phenanthrene. Various studies have explored the underlying pharmacological mechanisms of these compounds, which have shown antitumor, hypoglycemic, hypertensive, gastrointestinal-regulatory, visceral organ protection, antiaging, and neurorestorative effects. This paper presents a systematic review of the structural classification, biological activity, and pharmacological mechanisms of different chemical components obtained from D. officinale over the past decade. This review aims to provide a reference for future study and establish a foundation for clinical applications. Furthermore, this review identifies potential shortcomings in current research as well as potential directions and methodologies in future plant research.


Assuntos
Dendrobium , Dendrobium/química , Medicina Tradicional Chinesa
2.
Eur J Pharm Sci ; 188: 106530, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37459902

RESUMO

Pazopanib (PZ) is a multikinase inhibitor, which is mainly used in the treatment of soft tissue sarcoma and advanced renal cancer. However, because of its water insolubility, oral bioavailability is poor. At the same time, photo lability and high dose oral administration lead to severe hepatotoxicity, which is limited in clinical application. In this paper, the novel pazopanib-fumarate disodium glycyrrhizinate nanocrystalline micelles are successfully prepared by liquid-assisted ball milling. The prepared cocrystals and nanocrystalline micelle structures are systematically characterized by X-ray diffraction (XRD), differential scanning calorimetry (DSC) and Fourier Transform Infrared Spectrometer (FTIR) analysis. In vitro solubility and dissolution experiments show that the solubility and dissolution of nanocrystalline micelles are significantly improved under different simulated physiological conditions. The accelerated stabilization experiments show that the nanocrystalline micelles have good physical and chemical stability and showed excellent stability in water (Zeta potential was 62.39 mV). In addition, the in vivo bioavailability of nanocrystalline micelles is 3 times higher than that of PZ, and the therapeutic threshold (> 20 µg/mL) is up to 30 h. This new strategy provides a feasible solution to the undesirable properties of PZ.


Assuntos
Ácido Glicirretínico , Micelas , Fumaratos , Solubilidade , Varredura Diferencial de Calorimetria , Água , Difração de Raios X , Disponibilidade Biológica , Espectroscopia de Infravermelho com Transformada de Fourier
3.
Microorganisms ; 10(9)2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36144391

RESUMO

As one of the commonly isolated endophytic fungi, Alternaria has been known for the production of numerous secondary metabolites (SMs). However, its detailed genomic features and SM biosynthetic potential have not been extensively studied thus far. The present work focuses on the whole-genome sequencing and assembly of an endophytic strain Alternaria sp. SPS-2 derived from Echrysantha chrysantha Lindl. and gene annotation using various bioinformatic tools. The results of this study suggested that the genome of strain SPS-2 was 33.4 Mb in size with a GC content of 51% and an N50 scaffold of 2.6 Mb, and 9789 protein-coding genes, including 644 CAZyme-encoding genes, were discovered in strain SPS-2 through KEGG enrichment analysis. The antiSMASH results indicated that strain SPS-2 harbored 22 SM biosynthetic gene clusters (BGCs), 14 of which are cryptic and unknown. LS-MS/MS and GNPS-based analyses suggested that this endophytic fungus is a potential producer of bioactive SMs and merits further exploration and development.

4.
Front Microbiol ; 13: 878800, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35814656

RESUMO

Carbapenem-resistant Klebsiella pneumoniae (CRKP), a pathogen that causes severe nosocomial infections and yields a high mortality rate, poses a serious threat to global public health due to its high antimicrobial resistance. Bacteriophages encode polysaccharide-degrading enzymes referred to as depolymerases that cleave the capsular polysaccharide (CPS), one of the main virulence factors of K. pneumoniae. In this study, we identified and characterized a new capsule depolymerase K19-Dpo41 from K. pneumoniae bacteriophage SH-KP156570. Our characterization of K19-Dpo41 demonstrated that this depolymerase showed specific activities against K19-type K. pneumoniae. K19-Dpo41-mediated treatments promoted the sensitivity of a multidrug-resistant K19-type K. pneumoniae strain to the bactericidal effect of human serum and significantly increased the survival rate of Galleria mellonella infected with K19-type K. pneumoniae. Our results provided strong primary evidence that K19-Dpo41 was not only effective in capsular typing of K19-type K. pneumoniae but promising in terms of developing new alternative therapeutic strategies against K19-type CRKP infections in the future.

5.
J Pharmacol Toxicol Methods ; 106: 106913, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32822830

RESUMO

High-content screening (HCS) systems can be used for high-throughput screening of drugs in human embryonic stem cells (hESCs). However, hESCs require immunofluorescence staining with stemness markers (e.g., Oct-4) prior to HCS, which can be time consuming and labor intensive. In this study, we employed transgenic hESCs with enhanced green fluorescent protein driven by stemness gene Oct-4 promoter (Oct-4-EGFP-H9), in which the colony area and relative green fluorescence area inferred a state of hESC proliferation and stemness, respectively. The Oct-4-EGFP-H9 transgenic hESCs were cultured in mTeSR medium with different concentrations of 5-Fluorouracil (5-FU), vitamin C (VC), or retinoic acid (RA) for 5-7 days, followed by repeated imaging using the HCS system. Finally, the hESC colony area and green fluorescence area were calculated. Results showed that 5-FU treatment markedly reduced colony area in a dose-dependent manner, whereas VC and RA treatments did not. MTT assay and flow cytometry indicated that 5-FU inhibited the proliferation of hESCs significantly, verifying reliability of the data from the HCS system based on colony area analysis. The green fluorescence to total colony area ratio decreased with RA treatment, suggesting that RA significantly promoted differentiation, whereas 5-FU and VC had almost no effect, as verified by quantitative real-time polymerase chain reaction and western blot analysis. In conclusion, our study established a rapid and efficient drug screening system without the requirement of staining based on HCS.


Assuntos
Avaliação Pré-Clínica de Medicamentos/métodos , Ensaios de Triagem em Larga Escala/métodos , Células-Tronco Embrionárias Humanas/efeitos dos fármacos , Ácido Ascórbico , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Fluoruracila , Genes Reporter/genética , Proteínas de Fluorescência Verde/genética , Células-Tronco Embrionárias Humanas/fisiologia , Humanos , Processamento de Imagem Assistida por Computador , Fator 3 de Transcrição de Octâmero/genética , Regiões Promotoras Genéticas , Reprodutibilidade dos Testes , Software , Testes de Toxicidade Subaguda/métodos , Transgenes/genética , Tretinoína
6.
Mol Cancer Ther ; 19(10): 2001-2011, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32737157

RESUMO

PTEN deletion or mutation occurs in 30% to 60% of patients with glioblastoma (GBM) and is associated with poor prognosis. Efficacious therapy for this subgroup of patients is currently lacking. To identify potential target(s) to selectively suppress PTEN-deficient GBM growth, we performed a three-step synthetic lethal screen on LN18 PTEN wild-type (WT) and knockout (KO) isogeneic GBM cell lines using a library containing 606 target-selective inhibitors. A MCL1 inhibitor UMI-77 identified in the screen exhibited excellent suppression on the proliferation, colony formation, 3D spheroid, and neurosphere formation of PTEN-deficient GBM cells. Mechanistically, loss of PTEN in GBM cells led to upregulation of MCL1 in posttranslational level via inhibition of GSK3ß, and consequently confer cells resistance to apoptosis. Pharmacologic inhibition or knockdown of MCL1 blocked this PI3K-GSK3ß-MCL1 axis and caused reduction of several antiapoptotic proteins, finally induced massive caspase-3 cleavage and apoptosis. In both subcutaneous and orthotopic GBM models, knockdown of MCL1 significantly impaired the in vivo growth of PTEN-deficient xenografts. Moreover, the combination of UMI-77 and temozolomide synergistically killed PTEN-deficient GBM cells. Collectively, our work identified MCL1 as a promising target for PTEN-deficient GBM. For future clinical investigations, priority should be given to the development of a selective MCL1 inhibitor with efficient brain delivery and minimal in vivo toxicity.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Proteína de Sequência 1 de Leucemia de Células Mieloides/antagonistas & inibidores , Animais , Linhagem Celular Tumoral , Glioblastoma/patologia , Humanos , Camundongos , Camundongos Nus , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Cancer Cell Int ; 20: 337, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32714096

RESUMO

BACKGROUND: Glioblastoma multiforme (GBM) is the most common and lethal type of primary brain tumor. More than half of GBMs contain mutation(s) of PTEN/PI3K/AKT, making inhibitors targeting the PI3K pathway very attractive for clinical investigation. However, so far, PI3K/AKT/mTOR inhibitors have not achieved satisfactory therapeutic effects in clinical trials of GBM. In this study, we aimed to develop a high-throughput screening method for high-throughput identification of potential targeted agents that synergize with PI3K inhibitors in GBM. METHODS: A Sensitivity Index (SI)-based drug combination screening method was established to evaluate the interactions between BKM120, a pan-PI3K inhibitor, and compounds from a library of 606 target-selective inhibitors. Proliferation, colony and 3D spheroid formation assays, western blotting, comet assay, γ-H2AX staining were used to evaluate the anti-glioma effects of the top-ranked candidates. The drug combination effects were analyzed by the Chou-Talalay method. RESULTS: Six compounds were successfully identified from the drug screen, including three previously reported compounds that cause synergistic antitumor effects with PI3K/mTOR inhibitors. TH588, an putative MTH1 inhibitor exhibited significant synergy with BKM120 in suppressing the proliferation, colony formation and 3D spheroid formation of GBM cells. Further investigation revealed that both DNA damage and apoptosis were markedly enhanced upon combination treatment with TH588 and BKM120. Finally, activation of PI3K or overexpression of AKT compromised the anti-glioma efficacy of TH588. CONCLUSIONS: The screening method developed in this study demonstrated its usefulness in the rapid identification of synergistic drug combinations of PI3K inhibitors and targeted agents.

8.
Aging (Albany NY) ; 12(2): 1624-1642, 2020 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-31986488

RESUMO

D-alpha-tocopheryl polyethylene glycol 1000 succinate (TPGS1000) is the most active water-soluble derivative of vitamin E and has been widely used as a carrier of solvents, plasticizers, emulsifiers, absorbent agents and refractory drug delivery systems. However, its anti-hepatocellular carcinoma (HCC) properties have not been explored. HCC cells were treated with different concentrations of TPGS1000. Cell survival was tested by CCK8 assay, and cell migration was tested by wound healing and Transwell assay. EdU staining verified cell proliferation, and signalling pathway was assayed by Western blot analysis. The BALB/c-nu mouse xenograft model was established to test HCC cell growth in vivo. In vitro TPGS1000 significantly inhibited the viability and mobility of HCC cells (HepG2, Hep3B and Huh7) in a dose-dependent manner. Cell cycle analysis indicated that TPGS1000 treatment arrested the HCC cell cycle in the G0/G1 phase, and induction of cell apoptosis was confirmed by TUNEL and Annexin V-7-AAD staining. Further pharmacological analysis indicated that collapse of the transmembrane potential of mitochondria, increased ROS generation, PARP-induced cell apoptosis and FoxM1-p21-mediated cell cycle arresting, were involved in the anti-HCC activity of TPGS1000. Moreover, treatment in vivo with TPGS1000 effectively impaired the growth of HCC xenografts in nude mice.


Assuntos
Antineoplásicos/farmacologia , Vitamina E/análogos & derivados , Vitamina E/farmacologia , Animais , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Replicação do DNA , Modelos Animais de Doenças , Proteína Forkhead Box M1/metabolismo , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Front Microbiol ; 8: 2659, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29375524

RESUMO

Carbapenem-resistant Acinetobacter baumannii (CRAB) which is noted as a major pathogen associated with healthcare-associated infections has steadily developed beyond antibiotic control. Lytic bacteriophages with the characteristics of infecting and lysing specific bacteria have been used as a potential alternative to traditional antibiotics to solve multidrug-resistant bacterial infections. Here, we isolated A. baumannii-specific lytic phages and evaluated their potential therapeutic effect against lung infection caused by CRAB clinical strains. The combined lysis spectrum of four lytic phages' ranges was 87.5% (42 of 48) against CRAB clinical isolates. Genome sequence and analysis indicated that phage SH-Ab15519 is a novel phage which does not contain the virulence or antibiotic resistance genes. In vivo study indicated that phage SH-Ab15519 administered intranasally can effectively rescue mice from lethal A. baumannii lung infection without deleterious side effects. Our work explores the potential use of phages as an alternative therapeutic agent against the lung infection caused by CRAB strains.

11.
Cancer Invest ; 34(10): 477-488, 2016 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-27918216

RESUMO

S100P is known to affect tumor development and metastasis of various cancers, but its role in endometrial cancer is unclear. We reported that S100P expression was dramatically elevated in both endometrial squamous cell carcinoma and adenosquamous carcinoma, but not in adenocarcinoma and normal endometrial samples. Moreover, we revealed an oncogenic role of S100P promoting cell proliferation, invasion, and migration while reducing apoptosis, possibly via its upregulation and/or activation of receptors of advanced glycation end products and consequently the oncogenic PI3K-AKT and MAPK pathways. Therefore, S100P might be a specific biomarker and a potential drug target for squamous cell and adenosquamous carcinoma subtypes of endometrial cancer.


Assuntos
Proteínas de Ligação ao Cálcio/genética , Carcinoma Adenoescamoso/genética , Carcinoma de Células Escamosas/genética , Neoplasias do Endométrio/genética , Expressão Gênica , Proteínas de Neoplasias/genética , Apoptose/efeitos dos fármacos , Apoptose/genética , Biomarcadores Tumorais , Proteínas de Ligação ao Cálcio/metabolismo , Carcinoma Adenoescamoso/metabolismo , Carcinoma Adenoescamoso/patologia , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Sobrevivência Celular/efeitos dos fármacos , Cisplatino/farmacologia , Neoplasias do Endométrio/metabolismo , Neoplasias do Endométrio/patologia , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Proteínas de Neoplasias/metabolismo , Transdução de Sinais , Transfecção
12.
Expert Rev Proteomics ; 13(4): 411-20, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26954459

RESUMO

Most recently approved anti-cancer drugs by the US FDA are targeted therapeutic agents and this represents an important trend for future anticancer therapy. Unlike conventional chemotherapy that rarely considers individual differences, it is crucial for targeted therapies to identify the beneficial subgroup of patients for the treatment. Currently, genomics and transcriptomics are the major 'omic' analytics used in studies of drug response prediction. However, proteomic profiling excels both in its advantages of directly detecting an instantaneous dynamic of the whole proteome, which contains most current diagnostic markers and therapeutic targets. Moreover, proteomic profiling improves understanding of the mechanism for drug resistance and helps finding optimal combination therapy. This article reviews the recent success of applications of proteomic analytics in predicting the response to targeted anticancer therapeutics, and discusses the potential avenues and pitfalls of proteomic platforms and techniques used most in the field.


Assuntos
Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/metabolismo , Terapia de Alvo Molecular/métodos , Neoplasias/tratamento farmacológico , Proteoma/metabolismo , Proteômica/métodos , Animais , Perfilação da Expressão Gênica/métodos , Humanos , Neoplasias/diagnóstico , Proteoma/genética
13.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 1): o30, 2007 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-21200864

RESUMO

The title compond, C(19)H(24)O(5)·H(2)O, has two gibberellin A4 mol-ecules and two water mol-ecules in the asymmetric unit. The A and B rings have chair conformations, whereas the C and D rings have envelope conformations; the two rings which contain the lactone and carbonyl bridge adopt chair and envelope conformations. The crystal structure is established by O-H⋯O hydrogen bonds and supported by C-H⋯O hydrogen bonds.

14.
Carbohydr Res ; 339(13): 2219-24, 2004 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-15337449

RESUMO

A heteropolysaccharide obtained from an aqueous extract of dried stem of Dendrobium officinale Kimura and Migo by anion-exchange chromatography and gel-permeation chromatography, was investigated by chemical techniques and NMR spectroscopy, and is demonstrated to be a 2-O-acetylglucomannan, composed of mannose, glucose, and arabinose in 40.2:8.4:1 molar ratios. It has a backbone of (1-->4)-linked beta-d-mannopyranosyl residues and beta-d-glucopyranosyl residues, with branches at O-6 consisting of terminal and (1-->3)-linked Manp, (1-->3)-linked Glcp, and a small proportion of arabinofuranosyl residues at the terminal position. The acetyl groups are substituted at O-2 of (1-->4)-linked Manp and Glcp. The main repeating unit of the polysaccharides is reported.


Assuntos
Dendrobium/química , Mananas/química , Caules de Planta/química , Sequência de Carboidratos , Dissacarídeos/química , Espectroscopia de Ressonância Magnética , Mananas/isolamento & purificação , Espectrometria de Massas , Dados de Sequência Molecular , Oligossacarídeos/química , Oligossacarídeos/isolamento & purificação
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