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1.
World J Microbiol Biotechnol ; 40(7): 219, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38809492

RESUMO

Protectins, 10,17-dihydroxydocosahexaenoic acids (10,17-DiHDHAs), are belonged to specialized pro-resolving mediators (SPMs). Protectins are generated by polymorphonuclear leukocytes in humans and resolve inflammation and infection in trace amounts. However, the quantitative production of protectin DX 10-epimer (10-epi-PDX, 10R,17S-4Z,7Z,11E,13Z,15E,19Z-DiHDHA) has been not attempted to date. In this study, 10-epi-PDX was quantitatively produced from docosahexaenoic acid (DHA) by serial whole-cell biotransformation of Escherichia coli expressing arachidonate (ARA) 8R-lipoxygenase (8R-LOX) from the coral Plexaura homomalla and E. coli expressing ARA 15S-LOX from the bacterium Archangium violaceum. The optimal bioconversion conditions to produce 10R-hydroxydocosahexaenoic acid (10R-HDHA) and 10-epi-PDX were pH 8.0, 30 °C, 2.0 mM DHA, and 4.0 g/L cells; and pH 8.5, 20 °C, 1.4 mM 10R-HDHA, and 1.0 g/L cells, respectively. Under these optimized conditions, 2.0 mM (657 mg/L) DHA was converted into 1.2 mM (433 mg/L) 10-epi-PDX via 1.4 mM (482 mg/L) 10R-HDHA by the serial whole-cell biotransformation within 90 min, with a molar conversion of 60% and volumetric productivity of 0.8 mM/h (288 mg/L/h). To the best of our knowledge, this is the first quantitative production of 10-epi-PDX. Our results contribute to the efficient biocatalytic synthesis of SPMs.


Assuntos
Antozoários , Biotransformação , Ácidos Docosa-Hexaenoicos , Escherichia coli , Ácidos Docosa-Hexaenoicos/metabolismo , Escherichia coli/metabolismo , Escherichia coli/genética , Antozoários/microbiologia , Antozoários/metabolismo , Animais , Araquidonato 15-Lipoxigenase/metabolismo , Araquidonato Lipoxigenases/metabolismo , Araquidonato Lipoxigenases/genética , Concentração de Íons de Hidrogênio
2.
Angew Chem Int Ed Engl ; 63(21): e202402465, 2024 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-38482567

RESUMO

A targeted metabologenomic method was developed to selectively discover terminal oxazole-bearing natural products from bacteria. For this, genes encoding oxazole cyclase, a key enzyme in terminal oxazole biosynthesis, were chosen as the genomic signature to screen bacterial strains that may produce oxazole-bearing compounds. Sixteen strains were identified from the screening of a bacterial DNA library (1,000 strains) using oxazole cyclase gene-targeting polymerase chain reaction (PCR) primers. The PCR amplicon sequences were subjected to phylogenetic analysis and classified into nine clades. 1H-13C coupled-HSQC NMR spectra obtained from the culture extracts of the hit strains enabled the unequivocal detection of the target compounds, including five new oxazole compounds, based on the unique 1JCH values and chemical shifts of oxazole: lenzioxazole (1) possessing an unprecedented cyclopentane, permafroxazole (2) bearing a tetraene conjugated with carboxylic acid, tenebriazine (3) incorporating two modified amino acids, and methyl-oxazolomycins A and B (4 and 5). Tenebriazine displayed inhibitory activity against pathogenic fungi, whereas methyl-oxazolomycins A and B (4 and 5) selectively showed anti-proliferative activity against estrogen receptor-positive breast cancer cells. This metabologenomic method enables the logical and efficient discovery of new microbial natural products with a target structural motif without the need for isotopic labeling.


Assuntos
Produtos Biológicos , Oxazóis , Oxazóis/química , Oxazóis/farmacologia , Oxazóis/metabolismo , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Produtos Biológicos/metabolismo , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/química , Linhagem Celular Tumoral , Metabolômica , Estrutura Molecular , Proliferação de Células/efeitos dos fármacos , Descoberta de Drogas , Bactérias/efeitos dos fármacos
3.
J Am Chem Soc ; 145(36): 19676-19690, 2023 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-37642383

RESUMO

A targeted and logical discovery method was devised for natural products containing piperazic acid (Piz), which is biosynthesized from ornithine by l-ornithine N-hydroxylase (KtzI) and N-N bond formation enzyme (KtzT). Genomic signature-based screening of a bacterial DNA library (2020 strains) using polymerase chain reaction (PCR) primers targeting ktzT identified 62 strains (3.1%). The PCR amplicons of KtzT-encoding genes were phylogenetically analyzed to classify the 23 clades into two monophyletic groups, I and II. Cultivating hit strains in media supplemented with 15NH4Cl and applying 1H-15N heteronuclear multiple bond correlation (HMBC) along with 1H-15N heteronuclear single quantum coherence (HSQC) and 1H-15N HSQC-total correlation spectroscopy (HSQC-TOCSY) NMR experiments detected the spectroscopic signatures of Piz and modified Piz. Chemical investigation of the hit strains prioritized by genomic and spectroscopic signatures led to the identification of a new azinothricin congener, polyoxyperuin B seco acid (1), previously reported chloptosin (2) in group I, depsidomycin D (3) incorporating two dehydropiperazic acids (Dpz), and lenziamides A and B (4 and 5), structurally novel 31-membered cyclic decapeptides in group II. By consolidating the phylogenetic and chemical analyses, clade-structure relationships were elucidated for 19 of the 23 clades. Lenziamide A (4) inhibited STAT3 activation and induced G2/M cell cycle arrest, apoptotic cell death, and tumor growth suppression in human colorectal cancer cells. Moreover, lenziamide A (4) resensitized 5-fluorouracil (5-FU) activity in both in vitro cell cultures and the in vivo 5-FU-resistant tumor xenograft mouse model. This work demonstrates that the genomic and spectroscopic signature-based searches provide an efficient and general strategy for new bioactive natural products containing specific structural motifs.


Assuntos
Produtos Biológicos , Genômica , Humanos , Animais , Camundongos , Filogenia , Análise Espectral , Produtos Biológicos/farmacologia
4.
J Am Chem Soc ; 145(3): 1886-1896, 2023 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-36634356

RESUMO

The logical and effective discovery of macrolactams, structurally unique natural molecules with diverse biological activities, has been limited by a lack of targeted search methods. Herein, a targeted discovery method for natural macrolactams was devised by coupling genomic signature-based PCR screening of a bacterial DNA library with spectroscopic signature-based early identification of macrolactams. DNA library screening facilitated the efficient selection of 43 potential macrolactam-producing strains (3.6% of 1,188 strains screened). The PCR amplicons of the amine-deprotecting enzyme-coding genes were analyzed to predict the macrolactam type (α-methyl, α-alkyl, or ß-methyl) produced by the hit strains. 1H-15N HSQC-TOCSY NMR analysis of 15N-labeled culture extracts enabled macrolactam detection and structural type assignment without any purification steps. This method identified a high-titer Micromonospora strain producing salinilactam (1), a previously reported α-methyl macrolactam, and two Streptomyces strains producing new α-alkyl and ß-methyl macrolactams. Subsequent purification and spectroscopic analysis led to the structural revision of 1 and the discovery of muanlactam (2), an α-alkyl macrolactam with diene amide and tetraene chromophores, and concolactam (3), a ß-methyl macrolactam with a [16,6,6]-tricyclic skeleton. Detailed genomic analysis of the strains producing 1-3 identified putative biosynthetic gene clusters and pathways. Compound 2 displayed significant cytotoxicity against various cancer cell lines (IC50 = 1.58 µM against HCT116), whereas 3 showed inhibitory activity against Staphylococcus aureus sortase A. This genomic and spectroscopic signature-based method provides an efficient search strategy for new natural macrolactams and will be generally applicable for the discovery of nitrogen-bearing natural products.


Assuntos
Streptomyces , Estrutura Molecular , Lactamas Macrocíclicas/farmacologia , Lactamas Macrocíclicas/química , Streptomyces/metabolismo , Genômica , Reação em Cadeia da Polimerase , Família Multigênica
5.
Biochem Biophys Res Commun ; 559: 252-258, 2021 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-33984809

RESUMO

Telomeric repeat binding factor a (Terfa) derived from zebrafish is a homologous protein with human telomeric repeat binding factor 2 (TRF2). Terfa is known as a senescence-associated biomarker in various research through the zebrafish animal model. In addition, according to the findings so far, it has been confirmed that human or plant telomere binding proteins bind to telomeric DNA specialized for each species, but, in our result, Terfa shows it strongly binds to both human or plant type telomeric DNA. Here we characterized the DNA binding properties and demonstrate the solution structure of Terfa and identified residues participating in the interaction with both human and plant telomeric DNA. In DNA recognition of human and plant telomere binding proteins, the N-terminal loop and the α-helix 3 part of Myb domain were bound majorly, whereas, in the case of Terfa, the N-terminal loop, the α-helix 1-2 loop, and α-helix 2 of the Myb domain were dominantly bound. Therefore, when Terfa recognizes DNA, it was found that the binding module differs from previously known telomere binding proteins. The comparison of the structure of the telomere binding proteins provides an opportunity to understand more specifically how the structural properties of each telomere binding protein are associated with telomeric DNA binding from an evolutionary point of view.


Assuntos
DNA de Plantas/metabolismo , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Telômero/metabolismo , Proteínas de Peixe-Zebra/química , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/metabolismo , Animais , Sequência de Bases , Sítios de Ligação , Ligação Proteica , Domínios Proteicos , Soluções
6.
Biochem Biophys Res Commun ; 534: 815-821, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33168186

RESUMO

The BRG1-associated factor 60A (BAF60A), an SWI/SNF-related matrix-associated actin-dependent regulator of chromatin subfamily D member 1, has been known to be important for transcriptional activation and inhibition through the alteration of the DNA nucleosome. Although the association between BAF60A and p53 plays a critical role in tumor suppression, the interaction mode is still unclear. Here, we report the detailed interactions between BAF60A and p53 by both NMR spectroscopy and pull-down analysis. Both N-terminal region (BAF60ANR) and the SWIB domain (BAF60ASWIB) of BAF60A directly interact with the tetramerization domain of p53 (p53TET). NMR data show that Ile315, Met366, Ala388, and Tyr390 of BAF60ASWIB are mostly involved in p53TET binding. The calculated dissociation constant (KD) value between BAF60ASWIB and p53TET revealed relatively weak binding affinity, at approximately 0.3 ± 0.065 mM. Our data will enhance detailed interaction mechanism to elucidate the molecular basis of p53-mediated integration via BAF60A interaction.


Assuntos
Proteínas Cromossômicas não Histona/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Sítios de Ligação , Proteínas Cromossômicas não Histona/genética , Humanos , Simulação de Acoplamento Molecular , Ressonância Magnética Nuclear Biomolecular/métodos , Domínios e Motivos de Interação entre Proteínas , Mapas de Interação de Proteínas , Proteína Supressora de Tumor p53/genética
7.
Bioorg Med Chem Lett ; 50: 128322, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34407463

RESUMO

Eight compounds (1-8) including one novel nitrophenyl glycoside, ginkgonitroside (1) were isolated from the leaves of Ginkgo biloba, a popular medicinal plant. The structure of the new compound was characterized using extensive spectroscopic analyses via 1D and 2D NMR data interpretations, HR-ESIMS, and chemical transformation. To the best of our knowledge, the present study is the first to report the presence of nitrophenyl glycosides, which are relatively unique phytochemicals in natural products, in G. biloba. The isolated compounds (1-8) were examined for their effects on the regulation of mesenchymal stem cell (MSC) differentiation. Compounds 1-3 and 8 were able to suppress MSC differentiation toward adipocytes. In contrast, compounds 5 and 8 showed activity promoting osteogenic differentiation of MSCs. These findings demonstrate that the active compounds showed regulatory activity on MSC differentiation between adipocytes and osteocytes.


Assuntos
Adipócitos/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Ginkgo biloba/química , Glicosídeos/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Adipócitos/fisiologia , Animais , Diferenciação Celular/fisiologia , Linhagem Celular , Glicosídeos/química , Camundongos , Osteoblastos/fisiologia , Folhas de Planta/química
8.
Proc Natl Acad Sci U S A ; 115(16): 4152-4157, 2018 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-29610354

RESUMO

Recent studies point out the link between altered mitochondrial metabolism and cancer, and detailed understanding of mitochondrial metabolism requires real-time detection of its metabolites. Employing heteronuclear 2D NMR spectroscopy and 13C3-pyruvate, we propose in-organelle metabolomics that allows for the monitoring of mitochondrial metabolic changes in real time. The approach identified acetyl phosphate from human mitochondria, whose production has been largely neglected in eukaryotic metabolism since its first description about 70 years ago in bacteria. The kinetic profile of acetyl phosphate formation was biphasic, and its transient nature suggested its role as a metabolic intermediate. The method also allowed for the estimation of pyruvate dehydrogenase (PDH) enzyme activity through monitoring of the acetyl-CoA formation, independent of competing cytosolic metabolism. The results confirmed the positive regulation of mitochondrial PDH activity by p53, a well-known tumor suppressor. Our approach can easily be applied to other organelle-specific metabolic studies.


Assuntos
Metabolômica/métodos , Mitocôndrias/metabolismo , Ressonância Magnética Nuclear Biomolecular/métodos , Organofosfatos/metabolismo , Proteína Supressora de Tumor p53/fisiologia , Acrilatos/farmacologia , Sistemas Computacionais , Técnicas de Inativação de Genes , Genes p53 , Células HCT116 , Humanos , Fosforilação Oxidativa , Complexo Piruvato Desidrogenase/antagonistas & inibidores , Complexo Piruvato Desidrogenase/metabolismo , Proteína Supressora de Tumor p53/deficiência
9.
Molecules ; 27(1)2021 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-35011267

RESUMO

Armillariella tabescens (Scop.) Sing., a mushroom of the family Tricholomataceae, has been used in traditional oriental medicine to treat cholecystitis, improve bile secretion, and regulate bile-duct pressure. The present study evaluated the estrogen-like effects of A. tabescens using a cell-proliferation assay in an estrogen-receptor-positive breast cancer cell line (MCF-7). We found that the methanol extract of A. tabescens fruiting bodies promoted cell proliferation in MCF-7 cells. Using bioassay-guided fractionation of the methanol extract and chemical investigation, we isolated and identified four steroids and four fatty acids from the active fraction. All eight compounds were evaluated by E-screen assay for their estrogen-like effects in MCF-7 cells. Among the tested isolates, only (3ß,5α,22E)-ergost-22-en-3-ol promoted cell proliferation in MCF-7 cells; this effect was mitigated by the ER antagonist, ICI 182,780. The mechanism underlying the estrogen-like effect of (3ß,5α,22E)-ergost-22-en-3-ol was evaluated using Western blot analysis to detect the expression of extracellular signal-regulated kinase (ERK), phosphatidylinositol 3-kinase (PI3K), Akt, and estrogen receptor α (ERα). We found that (3ß,5α,22E)-ergost-22-en-3-ol induced an increase in phosphorylation of ERK, PI3K, Akt, and ERα. Together, these experimental results suggest that (3ß,5α,22E)-ergost-22-en-3-ol is responsible for the estrogen-like effects of A. tabescens and may potentially aid control of estrogenic activity in menopause.


Assuntos
Receptor alfa de Estrogênio/metabolismo , Estrona/farmacologia , Transdução de Sinais/efeitos dos fármacos , Agaricales/química , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Biomarcadores , Proliferação de Células/efeitos dos fármacos , Estrona/análogos & derivados , Estrona/isolamento & purificação , Estrona/uso terapêutico , Feminino , Fungos/química , Terapia de Reposição Hormonal , Humanos , Células MCF-7 , Modelos Biológicos , Estrutura Molecular
10.
Anal Chem ; 92(11): 7382-7387, 2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32392040

RESUMO

AMP-activated protein kinase (AMPK in human and AAK in C. elegans) is a master regulator of metabolism. It has many isotypes, but its isotype-dependent functions are largely unknown. By developing real-time in-organism NMR metabolomics for C. elegans, we were able to study different roles of the isotypic catalytic subunits of AAK/AMPK, AAK-1, and AAK-2 in live worms at the whole organism level. The aak-1 knockout animals exhibited enhanced glucose production under starvation, strikingly opposite to aak-2 knockout animals. Unusually high compensatory expression of the reciprocal isotypes in each KO strain and the results for the double KO animals suggested an unconventional phenotype-genotype relationship and the dominance of aak-2 in glucose production. The gene expression patterns showed that the differential phenotypes of aak-1 KO strain are due to reduced TCA and glycolysis and enhanced gluconeogenesis compared to the aak-2 KO strain. Subsequent 13C-isotope incorporation experiment showed that the glucose production in aak-1 KO occurs through the activation of fatty acid oxidation and glyoxylate shunt. Revealing differential roles of the isotypes of AAK/AMPK, our convenient approach is readily applicable to many C. elegans models for human metabolic diseases.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Metabolômica , Ressonância Magnética Nuclear Biomolecular , Animais , Caenorhabditis elegans/enzimologia , Domínio Catalítico , Humanos , Fatores de Tempo
11.
Chemistry ; 26(4): 788-794, 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31639234

RESUMO

This work shows that a hollow and microporous metal-free N,N'-phenylenebis(salicylideneimine) (salphen) network (H-MSN) can be engineered by Sonogashira coupling of [tetraiodo{di(Zn-salphen)}] building blocks with 1,4-diethynylbenzene in the presence of silica templates and by successive Zn and silica etching. Iron(III) ions could be incorporated into the H-MSN to form hollow and microporous Fe-disalphen networks (H-MFeSN) with enhanced microporosity and surface area. The H-MFeSN showed efficient catalytic performance and recyclability in the CO2 conversion to cyclic carbonates.

12.
Chemistry ; 26(54): 12343-12348, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32621780

RESUMO

Conjugated microporous polymer (CMP)-based energy-storage materials were developed for pseudocapacitors. Nanoparticulate CMP (N-CMP) with an average diameter of 41±4 nm was prepared through kinetic growth control in the Sonogashira coupling of 1,3,5-triethynylbenzene with 1,4-diiodobenzene. The N-CMP is rich in a diphenylacetylene moiety in its chemical structure. Through the FeCl3 -catalyzed oxidation of diphenylacetylene moieties, N-CMP with benzil moieties (N-CMP-BZ) was prepared and showed enhanced electrochemical performance as an electrode material of pseudocapacitors, compared with CMP, CMP-BZ, and N-CMP. In model studies, the benzil was redox active and showed two-electron reduction behavior. The excellent electrochemical performance of N-CMP-BZ is attributable to the enhanced utilization of functional sites by a nanosize effect and the additional redox contribution of benzil moieties.

13.
Langmuir ; 36(30): 8745-8752, 2020 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-32633126

RESUMO

Flexible and metal-economical electromagnetic interference (EMI) shielding films were fabricated based on microporous organic polymer (MOP) chemistry. MOP with amino groups (MOP-A) could be introduced to the surface of poly(ethylene terephthalate) (PET) fibers. Due to the microporosity and amino groups of MOP-A, Ag+ could be easily incorporated into PET@MOP-A. Through Ag-catalyzed electroless Cu deposition, PET@MOP-A@Cu films were fabricated. The morphological and chemical structures of the PET@MOP-A@Cu were characterized by scanning electron microscopy, X-ray diffraction studies, and X-ray photoelectron spectroscopy. Among the films, the PET@MOP-A@Cu-40 with 41 wt % Cu (a thickness of 0.64 µm) showed excellent EMI shielding performance with 64.3-73.8 dB against an EM of 8-12 GHz. Moreover, it showed retention of the original EMI shielding performance against 1000 bending (R = 5 mm) tests.

14.
Bioorg Med Chem Lett ; 30(24): 127641, 2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-33127538

RESUMO

Phytochemical analysis of methanol extracts of Ginkgo biloba leaves resulted in the isolation of a novel diarylpentanoid, ginkgobilol (1) and a known diarylpentanoid analog (2). The structure of the new compound was elucidated by analyzing NMR spectroscopic data and HR-ESIMS, and the absolute configuration was determined using gauge-including atomic orbital NMR chemical shift calculations, followed by DP4+ analysis and specific rotation value. Diarylpentanoids comprise two aromatic rings linked by a five-carbon bridge; these are relatively unique examples in natural products. To the best of our knowledge, the present study is the first to report the presence of diarylpentanoids in G. biloba. Compound 2 increased alkaline phosphatase (ALP) production in C3H10T1/2, a murine mesenchymal stem cell line, in a dose-dependent manner. The promotion of osteogenic differentiation by the active compound 2 mediated by induction of transcriptional ALP and osteopontin (OPN) gene expression was confirmed using quantitative real time polymerase chain reaction, thus indicating its remarkable bone formation activity.


Assuntos
Ginkgo biloba/química , Células-Tronco Mesenquimais/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Fosfatase Alcalina/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Camundongos , Osteopontina/metabolismo , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia
15.
Int J Mol Sci ; 21(23)2020 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-33261209

RESUMO

Rhubarb is a well-known herb worldwide and includes approximately 60 species of the Rheum genus. One of the representative plants is Rheum palmatum, which is prescribed as official rhubarb due to its pharmacological potential in the Korean and Chinese pharmacopoeia. In our bioactive screening, we found out that the EtOH extract of R. palmatum inhibited hepatic stellate cell (HSC) activation by transforming growth factor ß1 (TGF-ß1). Chemical investigation of the EtOH extract led to the isolation of chrysophanol 8-O-glucoside, which was determined by structural analysis using NMR spectroscopic techniques and electrospray ionization mass spectrometry (ESIMS). To elucidate the effects of chrysophanol 8-O-glucoside on HSC activation, activated LX-2 cells were treated for 48 h with chrysophanol 8-O-glucoside, and α-SMA and collagen, HSC activation markers, were measured by comparative quantitative real-time PCR (qPCR) and western blotting analysis. Chrysophanol 8-O-glucoside significantly inhibited the protein and mRNA expression of α-SMA and collagen compared with that in TGF-ß1-treated LX-2 cells. Next, the expression of phosphorylated SMAD2 (p-SMAD2) and p-STAT3 was measured and the translocation of p-STAT3 to the nucleus was analyzed by western blotting analysis. The expression of p-SMAD2 and p-STAT3 showed that chrysophanol 8-O-glucoside strongly downregulated STAT3 phosphorylation by inhibiting the nuclear translocation of p-STAT3, which is an important mechanism in HSC activation. Moreover, chrysophanol 8-O-glucoside suppressed the expression of p-p38, not that of p-JNK or p-Erk, which can activate STAT3 phosphorylation and inhibit MMP2 expression, the downstream target of STAT3 signaling. These findings provided experimental evidence concerning the hepatoprotective effects of chrysophanol 8-O-glucoside against liver damage and revealed the molecular basis underlying its anti-fibrotic effects through the blocking of HSC activation.


Assuntos
Antraquinonas/farmacologia , Glucosídeos/farmacologia , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Substâncias Protetoras/farmacologia , Rheum/química , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Antraquinonas/química , Etanol , Glucosídeos/química , Células Estreladas do Fígado/efeitos dos fármacos , Células Estreladas do Fígado/metabolismo , Células Estreladas do Fígado/patologia , Humanos , Fosforilação , Extratos Vegetais/farmacologia , Transdução de Sinais/efeitos dos fármacos
16.
Int J Mol Sci ; 21(7)2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32244797

RESUMO

Human SNF5 and BAF155 constitute the core subunit of multi-protein SWI/SNF chromatin-remodeling complexes that are required for ATP-dependent nucleosome mobility and transcriptional control. Human SNF5 (hSNF5) utilizes its repeat 1 (RPT1) domain to associate with the SWIRM domain of BAF155. Here, we employed X-ray crystallography, nuclear magnetic resonance (NMR) spectroscopy, and various biophysical methods in order to investigate the detailed binding mechanism between hSNF5 and BAF155. Multi-angle light scattering data clearly indicate that hSNF5171-258 and BAF155SWIRM are both monomeric in solution and they form a heterodimer. NMR data and crystal structure of the hSNF5171-258/BAF155SWIRM complex further reveal a unique binding interface, which involves a coil-to-helix transition upon protein binding. The newly formed αN helix of hSNF5171-258 interacts with the ß2-α1 loop of hSNF5 via hydrogen bonds and it also displays a hydrophobic interaction with BAF155SWIRM. Therefore, the N-terminal region of hSNF5171-258 plays an important role in tumorigenesis and our data will provide a structural clue for the pathogenesis of Rhabdoid tumors and malignant melanomas that originate from mutations in the N-terminal loop region of hSNF5.


Assuntos
Montagem e Desmontagem da Cromatina/genética , Mutação , Nucleossomos/genética , Proteína SMARCB1/genética , Fatores de Transcrição/genética , Sítios de Ligação/genética , Dicroísmo Circular , Cristalografia por Raios X , Regulação da Expressão Gênica , Humanos , Espectroscopia de Ressonância Magnética , Melanoma/genética , Melanoma/metabolismo , Melanoma/patologia , Nucleossomos/metabolismo , Ligação Proteica , Tumor Rabdoide/genética , Tumor Rabdoide/metabolismo , Tumor Rabdoide/patologia , Proteína SMARCB1/química , Proteína SMARCB1/metabolismo , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo
17.
Molecules ; 25(13)2020 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-32645838

RESUMO

Two-dimensional quantitative nuclear magnetic resonance (2D qNMR)-based metabolomics was performed to understand characteristic metabolic profiles in different aging regimes (crust from dry-aged beef, inner edible flesh of dry-aged beef, and wet-aged beef striploin) over 4 weeks. Samples were extracted using 0.6 M perchlorate to acquire polar metabolites. Partial least squares-discriminant analysis showed a good cumulative explained variation (R2 = 0.967) and predictive ability (Q2 = 0.935). Metabolites of crust and aged beef (dry- and wet-aged beef) were separated in the first week and showed a completely different aspect in the second week via NMR-based multivariable analyses. Moreover, NMR-based multivariable analyses could be used to distinguish the method, degree, and doneness of beef aging. Among them, the crust showed more unique metabolic changes that accelerated proteolysis (total free amino acids and biogenic amines) and inosine 5'-monophosphate depletion than dry-aged beef and generated specific microbial catabolites (3-indoxyl sulfate) and γ-aminobutyric acid (GABA), while asparagine, glutamine, tryptophan, and glucose in the crust were maintained or decreased. Compared to the crust, dry-aged beef showed similar patterns of biogenic amines, as well as bioactive compounds and GABA, without a decrease in free amino acids and glucose. Based on these results, the crust allows the inner dry-aged beef to be aged similarly to wet-aged beef without microbial effects. Thus, 2D qNMR-based metabolomic techniques could provide complementary information about biochemical factors for beef aging.


Assuntos
Análise de Alimentos , Conservação de Alimentos , Metabolômica , Ressonância Magnética Nuclear Biomolecular , Carne Vermelha/análise
18.
Molecules ; 25(7)2020 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-32276430

RESUMO

The global incidence of breast cancer has increased. However, there are many impediments to the development of safe and effective anticancer drugs. The aim of the present study was to evaluate the effect of aviculin isolated from Lespedeza cuneata (Dum. Cours.) G. Don. (Fabaceae) on MCF-7 human breast cancer cells and determine the underlying mechanism. Using the bioassay-guided isolation by water soluble tetrazolium salt (WST-1)-based Ez-Cytox assay, nine compounds (four lignan glycosides (1-4), three flavonoid glycosides (5-7), and two phenolic compounds (8 and 9)) were isolated from the ethyl acetate (EA) fraction of the L. cuneata methanolic extract. Of these, aviculin (2), a lignan glycoside, was the only compound that reduced metabolic activity on MCF-7 cells below 50% (IC50: 75.47 ± 2.23 µM). The underlying mechanism was analyzed using the annexin V Alexa Fluor 488 binding assay and Western blotting. Aviculin (2) was found to induce apoptotic cell death through the intrinsic apoptosis pathway, as indicated by the increased expression of initiator caspase-9, executioner caspase-7, and poly (ADP-ribose) polymerase (PARP). Aviculin (2)-induced apoptotic cell death was accompanied by an increase in the Bax/Bcl-2 ratio. These findings demonstrated that aviculin (2) could induce breast cancer cell apoptosis through the intrinsic apoptosis pathway, and it can therefore be considered an excellent candidate for herbal treatment of breast cancer.


Assuntos
Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Caspases/metabolismo , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Lespedeza/química , Mitocôndrias/metabolismo , Transdução de Sinais , Neoplasias da Mama/metabolismo , Forma do Núcleo Celular/efeitos dos fármacos , Cisplatino/farmacologia , Ativação Enzimática/efeitos dos fármacos , Feminino , Glicosídeos/química , Humanos , Células MCF-7 , Metanol/química , Mitocôndrias/efeitos dos fármacos , Extratos Vegetais/farmacologia , Transdução de Sinais/efeitos dos fármacos
19.
Bioorg Chem ; 87: 117-122, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30884305

RESUMO

Curcuma zedoaria rhizome (Zingiberaceae) is a well-known traditional medicinal plant used in Ayurvedic and traditional Chinese medicine to treat various cancers. This study aimed to identify the cytotoxic components from C. zedoaria rhizomes that act against gastric cancer, which is the third leading cause of death from cancer worldwide because the MeOH extract of C. zedoaria rhizome was found to show a cytotoxic effect against gastric cancer AGS cells. Repeated column chromatography and semi-preparative HPLC purification were used to separate the components from the C. zedoaria MeOH extract. Two new sesquiterpenes, curcumenol-9,10-epoxide (1) and curcuzedoalide B (2), and 12 known related sesquiterpenes (3-14) were isolated from the C. zedoaria MeOH extract. The structures of new compounds were determined by 1D and 2D NMR spectroscopic experiments and HR-ESIMS, and quantum chemical ECD calculations. The cytotoxic effects of the isolated compounds were measured in human gastric cancer AGS cells using an MTT cell viability assay. Compounds 9, 10, and 12 exhibited cytotoxic effects against gastric cancer AGS cells, with IC50 values in the range of 212-392 µM. These findings provide further experimental scientific evidence to support the traditional use of C. zedoaria rhizomes for the treatment of cancer. Curcumenol (9), 4,8-dioxo-6ß-methoxy-7α,11-epoxycarabrane (10), and zedoarofuran (12) were identified as the main cytotoxic components in C. zedoaria rhizomes.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Curcuma/química , Sesquiterpenos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Teoria da Densidade Funcional , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Modelos Moleculares , Estrutura Molecular , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Relação Estrutura-Atividade , Células Tumorais Cultivadas
20.
Bioorg Chem ; 91: 103145, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31357073

RESUMO

The root bark of Ulmus davidiana var. japonica (Ulmaceae), commonly known as yugeunpi, has been used as a traditional Korean medicine for the treatment of gastroenteric and inflammatory disorders. As part of continuing projects to discover bioactive natural products from traditional medicinal plants with pharmacological potential, phytochemical investigation of the root bark of this plant was carried out. This led to the successful isolation of a new chromane derivative (1) and 22 known compounds: catechin derivatives (2-5), megastigmane glycoside (6), dihydrochalcone glycosides (7 and 8), flavanone glycosides (9 and 10), coumarins (11 and 12), lignan derivatives (13-17), and phenolic compounds (18-23). The structure of the new compound (1) was determined with 1D and 2D NMR spectroscopy and HR-ESIMS, and its absolute configurations were achieved by chemical reactions and the gauge-including atomic orbital (GIAO) NMR chemical shifts calculations. All the isolated compounds were evaluated for their potential biological activities including neuro-protective, anti-neuroinflammatory, and anti-Helicobacter pylori activities. Among the isolates, compounds 1, 8, and 20 displayed stronger potency by causing a greater increase in the production and the activity of nerve growth factor (NGF) in C6 glioma cells (147.04 ±â€¯4.87, 206.27 ±â€¯6.70, and 143.70 ±â€¯0.88%, respectively), whereas compounds 11, 14, and 19 inhibited nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated murine microglial cells (IC50 of 18.72, 12.31, and, 21.40 µM, respectively). In addition, compounds 1, 11, 18, and 20 showed anti-H. pylori activity with MIC values of 25 or 50 µM against two strains of H. pylori 51 and 43504. These findings provide scientific evidence that supports the traditional usage of U. davidiana var. japonica root bark in the treatment of gastroenteric and inflammatory disorders.


Assuntos
Antibacterianos/farmacologia , Anti-Inflamatórios/farmacologia , Fármacos Neuroprotetores/farmacologia , Casca de Planta/química , Extratos Vegetais/farmacologia , Ulmus/química , Animais , Células Cultivadas , Glioma/tratamento farmacológico , Glioma/metabolismo , Glioma/patologia , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/microbiologia , Helicobacter pylori/efeitos dos fármacos , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Inflamação/patologia , Camundongos , Microglia/efeitos dos fármacos , Microglia/patologia , Fator de Crescimento Neural/metabolismo , Óxido Nítrico/metabolismo , Raízes de Plantas/química , Ratos
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