RESUMO
The increasing prevalence of non-alcoholic fatty liver disease (NAFLD) poses a growing challenge in terms of its prevention and treatment. The 'multiple hits' hypothesis of multiple insults, such as dietary fat intake, de novo lipogenesis, insulin resistance, oxidative stress, mitochondrial dysfunction, gut dysbiosis and hepatic inflammation, can provide a more accurate explanation of the pathogenesis of NAFLD. Betaine plays important roles in regulating the genes associated with NAFLD through anti-inflammatory effects, increased free fatty oxidation, anti-lipogenic effects and improved insulin resistance and mitochondrial function; however, the mechanism of betaine remains elusive.
Assuntos
Resistência à Insulina , Hepatopatia Gordurosa não Alcoólica , Betaína/metabolismo , Betaína/farmacologia , Betaína/uso terapêutico , Humanos , Lipogênese , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/etiologiaRESUMO
Mangrove-derived actinobacteria strains are well-known for producing novel secondary metabolites. The polycyclic tetramate macrolactam (PTM), ikarugamycin (IKA) isolated from Streptomyces xiamenensis 318, exhibits antiproliferative activities against pancreatic ductal adenocarcinoma (PDAC) in vitro. However, the protein target for bioactive IKA is unclear. In this study, whole transcriptome-based profiling revealed that the glycolysis pathway is significantly affected by IKA. Metabolomic studies demonstrated that IKA treatment induces a significant drop in glucose-6-phosphate and a slight increase in intracellular glucose level. Analysis of glucose consumption, lactate production, and the extracellular acidification rate confirmed the inhibitory role of IKA on the glycolytic flux in PDAC cells. Surface plasmon resonance (SPR) experiments and docking studies identified the key enzyme of glycolysis, hexokinase 2 (HK2), as a molecular target of IKA. Moreover, IKA reduced tumor size without overt cytotoxicity in mice with PDAC xenografts and increased chemotherapy response to gemcitabine in PDAC cells in vitro. Taken together, IKA can block glycolysis in pancreatic cancer by targeting HK2, which may be a potential drug candidate for PDAC treatment.
Assuntos
Hexoquinase/metabolismo , Lactamas/farmacologia , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Glucose/metabolismo , Glicólise/efeitos dos fármacos , Humanos , Imuno-Histoquímica , Ácido Láctico/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Reação em Cadeia da Polimerase em Tempo Real , Ressonância de Plasmônio de SuperfícieRESUMO
A concise total synthesis of an exceedingly potent anti-inflammatory agent violacin A as well as the preparation of thirty analogues of this lead from commercially available orcinol are described. Highlights of our synthetic efforts involve Friedel-Crafts acylation, the regioselective etherification and esterification of phenolic hydroxyl groups, and Baker-Venkatamaran rearrangement to form basic skeleton of violacin A. The deprotection reaction with Pd-catalytic was involved to avoid the elimination of the hemiacetal hydroxyl at C2. In addition, all synthetic compounds were screened for anti-inflammatory activity against nitric oxide (NO) production using lipopolysaccharide (LPS)-induced Raw264.7 cells. A range of violacin A derivatives 11b, 11d, 11f, 12e, 12g, 13g, 17d-g exhibited stronger anti-inflammatory effect than that of violacin A. Notably, halogeno-benzyloxy substituent at C-7 were favourable for anti-inflammatory activities of violacin A derivatives. Additionally, Western blot results indicated halogeno-benzyloxy derivatives inhibited pro-inflammatory cytokines releases correlated with the suppression of NF-κB signaling pathway.
Assuntos
Anti-Inflamatórios/uso terapêutico , Ciclotídeos/química , Ciclotídeos/síntese química , Anti-Inflamatórios/farmacologia , Humanos , Estrutura MolecularRESUMO
Polycyclic tetramate macrolactams (PTMs) are a widely distributed class of structurally complex natural products, and most of them exhibit multiple biological activities. However, the transcriptional regulators (TRs) involved in the regulation of PTM production have seldom been reported. Here, we identified three TRs, i.e., Sxim_22880, CvnABCSx, and WblASx, and revealed their positive roles in the regulation of PTM biosynthesis in mangrove-derived Streptomyces xiamenensis 318. This strain produces a considerable amount of PTMs at 30 °C, but the production of PTMs is mostly blocked at 37 °C. Quantitative real-time PCR analysis confirmed that the transcriptions of PTM biosynthetic genes were downregulated. We determined that the transcriptions of several putative TRs, i.e., WblASx, Sxim_22880, and CvnCSx, were significantly downregulated under such heat-shock conditions. We showed that the transcription of PTM biosynthetic genes and the production of PTMs could be restored at 37 °C if the impaired transcriptions of wblASx, sxim_22880, and cvnABCSx were restored. Electrophoretic mobility shift assays showed that none of these TRs could bind to the promoter region of the PTM gene cluster, suggesting their indirect but positive involvement in the regulation on PTM production. Moreover, concurrent overexpression of the three TRs in S. xiamenensis 318 resulted in a 242.5% increase in PTM production when the strain was cultured at 30 °C. Furthermore, overexpression of these three TRs in Streptomyces sp. FR-008 and S. albus J1074 stimulated the production of new secondary metabolites, indicating that these conserved TRs could be used to activate cryptic secondary metabolite gene clusters in Streptomyces.
Assuntos
Produtos Biológicos/metabolismo , Regulação Bacteriana da Expressão Gênica , Compostos Policíclicos/metabolismo , Streptomyces/genética , Streptomyces/metabolismo , Fatores de Transcrição/metabolismo , Vias Biossintéticas/genética , DNA Bacteriano/metabolismo , Ensaio de Desvio de Mobilidade Eletroforética , Resposta ao Choque Térmico , Ligação Proteica , Streptomyces/efeitos da radiação , Temperatura , Fatores de Transcrição/genética , Transcrição Gênica/efeitos da radiaçãoRESUMO
Three new alkylated benzoquinones, 2-hydroxy-5-ethoxy-3-nonyl-1,4-benzoquinone (1), 5-O-butyl-embelin (2), and 2,5-dihydroxy-6-methyl-3-pentadecyl-1,4-benzoquinone (3), together with seven known analogues (4-10), were isolated from the stems and twigs of mangrove plant, Aegiceras corniculatum. Their structural elucidation was achieved by spectroscopic methods, chemical exchanging experiments, and semisynthesis method. The cytotoxic activities of all the isolated compounds were evaluated by MTT assay. Compounds 1, 2, 8, 9, and 10 possess varying degrees of selective cytotoxicity against HL-60, HepG2, BGC-823, and A2780 cell lines.[Formula: see text].
Assuntos
Neoplasias Ovarianas , Primulaceae , Benzoquinonas , Linhagem Celular Tumoral , Feminino , Humanos , Estrutura MolecularRESUMO
The pleiotropic transcriptional regulator AdpA positively controls morphological differentiation and regulates secondary metabolism in most Streptomyces species. Streptomyces xiamenensis 318 has a linear chromosome 5.96 Mb in size. How AdpA affects secondary metabolism and morphological differentiation in such a naturally minimized genomic background is unknown. Here, we demonstrated that AdpA Sx , an AdpA orthologue in S. xiamenensis, negatively regulates cell growth and sporulation and bidirectionally regulates the biosynthesis of xiamenmycin and polycyclic tetramate macrolactams (PTMs) in S. xiamenensis 318. Overexpression of the adpASx gene in S. xiamenensis 318 had negative effects on morphological differentiation and resulted in reduced transcription of putative ssgA, ftsZ, ftsH, amfC, whiB, wblA1, wblA2, wblE, and a gene encoding sporulation-associated protein (sxim_29740), whereas the transcription of putative bldD and bldA genes was upregulated. Overexpression of adpASx led to significantly enhanced production of xiamenmycin but had detrimental effects on the production of PTMs. As expected, the transcriptional level of the xim gene cluster was upregulated, whereas the PTM gene cluster was downregulated. Moreover, AdpA Sx negatively regulated the transcription of its own gene. Electrophoretic mobility shift assays revealed that AdpA Sx can bind the promoter regions of structural genes of both the xim and PTM gene clusters as well as to the promoter regions of genes potentially involved in the cell growth and differentiation of S. xiamenensis 318. We report that an AdpA homologue has negative effects on morphological differentiation in S. xiamenensis 318, a finding confirmed when AdpA Sx was introduced into the heterologous host Streptomyces lividans TK24.IMPORTANCE AdpA is a key regulator of secondary metabolism and morphological differentiation in Streptomyces species. However, AdpA had not been reported to negatively regulate morphological differentiation. Here, we characterized the regulatory role of AdpA Sx in Streptomyces xiamenensis 318, which has a naturally streamlined genome. In this strain, AdpA Sx negatively regulated cell growth and morphological differentiation by directly controlling genes associated with these functions. AdpA Sx also bidirectionally controlled the biosynthesis of xiamenmycin and PTMs by directly regulating their gene clusters rather than through other regulators. Our findings provide additional evidence for the versatility of AdpA in regulating morphological differentiation and secondary metabolism in Streptomyces.
Assuntos
Proteínas de Bactérias/metabolismo , Diferenciação Celular , Streptomyces/citologia , Streptomyces/metabolismo , Transativadores/metabolismo , Proteínas de Bactérias/genética , Regulação Bacteriana da Expressão Gênica , Genes Bacterianos/genética , Família Multigênica , Metabolismo Secundário , Alinhamento de Sequência , Análise de Sequência de Proteína , Deleção de Sequência , Streptomyces/genética , Streptomyces/crescimento & desenvolvimento , Transativadores/genéticaRESUMO
A new chromanone derivative, named violacin A (1), was isolated from the fermentation broth of Streptomyces violaceoruber as a potential anti-inflammatory compound. The structure of violacin A was established using comprehensive NMR spectroscopic data analysis together with UV, IR, and MS data. The anti-inflammatory effects and action mechanisms of violacin A were investigated in vitro. The results demonstrated that violacin A attenuated the production of NO, IL-1ß, IL-6, and TNF-α as well as inhibited the expression of iNOS in LPS-induced RAW 264.7 cells. Additionally, Western blot and qRT-PCR results revealed that 1 down-regulated pro-inflammatory cytokines expression correlated with the suppression of NF-κB signaling pathway.
Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Ciclotídeos/farmacologia , Streptomyces/química , Animais , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/metabolismo , Ciclotídeos/biossíntese , Ciclotídeos/química , Relação Dose-Resposta a Droga , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Camundongos , Estrutura Molecular , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II/metabolismo , Células RAW 264.7 , Transdução de Sinais/efeitos dos fármacos , Relação Estrutura-AtividadeRESUMO
Two unique pentacyclic N,C-coupled naphthylisoquinolines, the ancistrocyclinones A (5) and B (6), were discovered in the Chinese liana Ancistrocladus tectorius. Furthermore, six known, likewise N,C-coupled alkaloids, viz., ancistrocladinium A (7a) and its mono- and bisphenolic analogs 8a and 9a were isolated, along with their atropo-diastereomers 7b, 8b, and 9b. The stereostructures of 5 and 6 were determined by HRESIMS, 1D and 2D NMR, oxidative degradation, and ECD calculations. The pentacyclic ancistrocyclinones A (5) and B (6) are structurally similar to berberine alkaloids - yet arising from a most different biosynthetic pathway: they are apparently formed by N,C-coupling of their polyketide-derived molecular halves, followed by oxidative cyclo-condensation. Biomimetic conversion of the co-occurring 4'-O-demethylancistrocladinium A (8a) to ancistrocyclinone A (5) via a quinoid intermediate supported the postulated pathway. Ancistrocyclinone A (5) was found to significantly inhibit the viability of drug-sensitive human leukemia (CCRF-CEM) and multidrug-resistant tumor cells (CEM/ADR5000) with comparable efficacies.
Assuntos
Alcaloides/química , Alcaloides/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Caryophyllales/química , Isoquinolinas/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , HumanosRESUMO
The relative and absolute configurations of xiamenmycin A, a benzopyran compound isolated from Streptomyces xiamenensis 318 with a highly potent anti-fibrotic activity, have been characterized through the total synthesis. The key steps include the construction of the 3-chromanol moiety via Sharpless epoxidation followed by regio- and diastereo-selective cyclization and introduction of the threonine moiety at a later stage via Pd-catalysed aminocarbonylation in a one-pot procedure. The stereochemical assignment of natural xiamenmycin A has been accordingly revised to be 2R, 3S, 3'S, 4'R.
Assuntos
Benzopiranos/química , Benzopiranos/síntese química , Treonina/análogos & derivados , Estrutura Molecular , Estereoisomerismo , Treonina/síntese química , Treonina/químicaRESUMO
Xiamenmycin A is an antifibrotic leading compound with a benzopyran skeleton that is isolated from mangrove-derived Streptomyces xiamenensis. As a promising small molecule for fibrotic diseases, less information is known about its metabolic characteristics in vivo. In this study, the time-course of xiamenmycin A in mouse plasma was investigated by relative quantification. After two types of administration of xiamenmycin A at a single dose of 10 mg/kg, the plasma concentrations were measured quantitatively by LC-MS/MS. The dynamic changes in the xiamenmycin A concentration showed rapid absorption and quick elimination in plasma post-administration. Four metabolites (M1-M4) were identified in blood by UPLC-QTOF-MS, and xiamenmycin B (M3) is the principal metabolite in vivo, as verified by comparison of the authentic standard sample. The structures of other metabolites were identified based on the characteristics of their MS and MS/MS data. The newly identified metabolites are useful for understanding the metabolism of xiamenmycin A in vivo, aiming at the development of an anti-fibrotic drug candidate for the therapeutic treatment of excessive fibrotic diseases.
Assuntos
Benzopiranos/sangue , Fibrinolíticos/sangue , Treonina/análogos & derivados , Animais , Biotransformação , Cromatografia Líquida de Alta Pressão , Feminino , Espectrometria de Massas , Camundongos , Camundongos Endogâmicos C57BL , Espectrometria de Massas em Tandem , Treonina/sangueRESUMO
Cellular replicative capacity is a therapeutic target for regenerative medicine as well as cancer treatment. The mechanism of replicative senescence and cell immortality is still unclear. We investigated the diauxic growth of Saccharomyces cerevisiae and demonstrate that the replicative capacity revealed by the yeast growth curve can be understood by using the dynamical property of the molecular-cellular network regulating S. cerevisiae. The endogenous network we proposed has a limit cycle when pheromone signaling is disabled, consistent with the exponential growth phase with an infinite replicative capacity. In the post-diauxic phase, the cooperative effect of the pheromone activated mitogen-activated protein kinase (MAPK) signaling pathway with the cell cycle leads to a fixed point attractor instead of the limit cycle. The cells stop dividing after several generations counting from the beginning of the post-diauxic growth. By tuning the MAPK pathway, S. cerevisiae therefore programs the number of offsprings it replicates.
Assuntos
Regulação Fúngica da Expressão Gênica , Saccharomyces cerevisiae/fisiologia , Ciclo Celular , Perfilação da Expressão Gênica , Glucose/química , Sistema de Sinalização das MAP Quinases , Modelos Teóricos , Simulação de Dinâmica Molecular , Feromônios/metabolismo , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Transdução de Sinais , Biologia de SistemasRESUMO
Ectodermal neural cortex 1 (ENC1) is a protein that plays a crucial role in the regulation of various cellular processes such as cell proliferation, differentiation, and apoptosis. Numerous studies have shown that ENC1 is overexpressed in various types of cancers, including breast, lung, pancreatic, and colorectal cancer, and its upregulation is correlated with a poorer prognosis. In addition to its role in cancer growth and spreading, ENC1 has also been linked to neuronal process development and neural crest cell differentiation. In this review, we provide an overview of the current knowledge on the relationship between ENC1 and cancer. We discuss the molecular mechanisms by which ENC1 contributes to tumorigenesis, including its involvement in multiple oncogenic signaling pathways. We also summarize the potential of targeting ENC1 for cancer therapy, as its inhibition has been shown to significantly reduce cancer cell invasion, growth, and metastasis. Finally, we highlight the remaining gaps in our understanding of ENC1's role in cancer and propose potential directions for future research.
Assuntos
Proteínas dos Microfilamentos , Neoplasias , Proteínas Nucleares , Proteínas dos Microfilamentos/metabolismo , Neoplasias/genética , Neuritos/metabolismo , Proteínas Nucleares/metabolismo , HumanosRESUMO
Atherosclerosis, an immunoinflammatory disease of medium and large arteries, is associated with life-threatening clinical events, such as acute coronary syndromes and stroke. Chronic inflammation and impaired lipoprotein metabolism are considered to be among the leading causes of atherosclerosis, while numerous risk factors, including arterial hypertension, diabetes mellitus, obesity, and aging, can contribute to the development of the disease. In recent years, emerging evidence has underlined the key role of mitochondrial dysfunction in the pathogenesis of atherosclerosis. Mitochondrial dysfunction is believed to result in an increase in reactive oxygen species, leading to oxidative stress, chronic inflammation, and intracellular lipid deposition, all of which can contribute to the pathogenesis of atherosclerosis. Critical cells, including endothelial cells, vascular smooth muscle cells, and macrophages, play an important role in atherosclerosis. Mitochondrial function is also involved in maintaining the normal function of these cells. To better understand the relationship between mitochondrial dysfunction and atherosclerosis, this review summarizes the findings of recent studies and discusses the role of mitochondrial dysfunction in the risk factors and critical cells of atherosclerosis. FACTS: OPEN QUESTIONS.
Assuntos
Aterosclerose , Mitocôndrias , Estresse Oxidativo , Humanos , Aterosclerose/metabolismo , Aterosclerose/patologia , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Animais , Estresse Oxidativo/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Fatores de Risco , Inflamação/metabolismo , Inflamação/patologia , Macrófagos/metabolismo , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologiaRESUMO
Carboncarbon (C-C) bonds serve as the fundamental structural backbone of organic molecules. As a critical CC bond forming enzyme, α-oxoamine synthase is responsible for the synthesis of α-amino ketones by performing the condensation reaction between amino acids and acyl-CoAs. We previously identified an α-oxoamine synthase (AOS), named as Alb29, involved in albogrisin biosynthesis in Streptomyces albogriseolus MGR072. This enzyme belongs to the α-oxoamine synthase family, a subfamily under the pyridoxal 5'-phosphate (PLP) dependent enzyme superfamily. In this study, we report the crystal structures of Alb29 bound to PLP and L-Glu, which provide the atomic-level structural insights into the substrate recognition by Alb29. We discover that Alb29 can catalyze the amino transformation from L-Gln to L-Glu, besides the condensation of L-Glu with ß-methylcrotonyl coenzyme A. Subsequent structural analysis has revealed that one flexible loop in Alb29 plays an important role in both amino transformation and condensation. Based on the crystal structure of the S87G mutant in the loop region, we capture two distinct conformations of the flexible loop in the active site, compared with the wild-type Alb29. Our study offers valuable insights into the catalytic mechanism underlying substrate recognition of Alb29.
Assuntos
Ácido Glutâmico , Especificidade por Substrato , Ácido Glutâmico/química , Modelos Moleculares , Streptomyces/enzimologia , Cristalografia por Raios X , Domínio Catalítico , Conformação Proteica , Fosfato de Piridoxal/metabolismo , Fosfato de Piridoxal/química , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Relação Estrutura-AtividadeRESUMO
BACKGROUND: Ovarian cancer (OC) is a prevalent malignancy in the female reproductive system, and developing effective targeted therapies for this disease remains challenging. The aim of this study was to use clinically-relevant OC models to evaluate the therapeutic effectiveness of RC48, an antibody-drug conjugate (ADC) targeting HER2, either alone or in combination with the VEGFR inhibitor Cediranib Maleate (CM), for the treatment of advanced OC. METHODS: OC tumor specimens and cell lines were analyzed to determine HER2 and VEGFR expression by Western blot, immunocytochemistry and immunofluorescence. Moreover, the OC cell lines, cell-derived xenograft (CDX) and patient-derived xenograft (PDX) models were treated with RC48 and/or CM and then subjected to cell proliferation, viability, apoptosis, and tumor growth analyses to evaluate the feasibility of combination therapy for OC both in vitro and in vivo. Additionally, RNA-Seq was performed to investigate the critical mechanism underlying the combination therapy of RC48 and CM. RESULTS: Our results demonstrated that RC48 alone effectively targeted and inhibited the growth of HER2-positive OC tumors in both cell lines and PDX models. Furthermore, the combination of RC48 and CM synergistically induced tumor regression in human OC cell lines, as well as CDX and PDX models. Mechanistically, we observed that the combination treatment inhibited the growth of OC cells involved inducing apoptosis and suppressing cell motility. RNA-seq analysis provided further mechanistic insights and revealed that co-administration of RC48 and CM downregulated multiple cancer-related pathways, including the AKT/mTOR pathway, cell cycle, and cell proliferation. Notably, our data further confirmed that the PI3K-AKT pathway played a key role in the inhibition of proliferation triggered by combinational treatment of RC48 and CM in OC cells. CONCLUSIONS: These findings provide a preclinical framework supporting the potential of dual targeting HER2 and VEGFR as a promising therapeutic strategy to improve outcomes in patients with OC.
Assuntos
Neoplasias Ovarianas , Proteínas Proto-Oncogênicas c-akt , Humanos , Feminino , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Carcinoma Epitelial do Ovário , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Proliferação de Células , Linhagem Celular TumoralRESUMO
Mangrove-derived actinomycetes are promising sources of bioactive natural products. In this study, using homologous screening of the biosynthetic genes and anti-microorganism/tumor assaying, 163 strains of actinomycetes isolated from mangrove sediments were investigated for their potential to produce halogenated metabolites. The FADH2-dependent halogenase genes, identified in PCR-screening, were clustered in distinct clades in the phylogenetic analysis. The coexistence of either polyketide synthase (PKS) or nonribosomal peptide synthetase (NRPS) as the backbone synthetases in the strains harboring the halogenase indicated that these strains had the potential to produce structurally diversified antibiotics. As a validation, a new enduracidin producer, Streptomyces atrovirens MGR140, was identified and confirmed by gene disruption and HPLC analysis. Moreover, a putative ansamycin biosynthesis gene cluster was detected in Streptomyces albogriseolus MGR072. Our results highlight that combined genome mining is an efficient technique to tap promising sources of halogenated natural products synthesized by mangrove-derived actinomycetes.
Assuntos
Actinobacteria/genética , Actinobacteria/metabolismo , Produtos Biológicos/metabolismo , Halogenação/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Genes Bacterianos/genética , Peptídeo Sintases/genética , Peptídeo Sintases/metabolismo , Filogenia , Policetídeo Sintases/genética , Policetídeo Sintases/metabolismo , Streptomyces/genética , Streptomyces/metabolismoRESUMO
The benzopyran compound obtained by cultivating a mangrove-derived strain, Streptomyces xiamenensis strain 318, shows multiple biological effects, including anti-fibrotic and anti-hypertrophic scar properties. To increase the diversity in the structures of the available benzopyrans, by means of biosynthesis, the strain was screened for spontaneous rifampicin resistance (Rif), and a mutated rpsL gene to confer streptomycin resistance (Str), was introduced into the S. xiamenensis strain M1-94P that originated from deep-sea sediments. Two new benzopyran derivatives, named xiamenmycin C (1) and D (2), were isolated from the crude extracts of a selected Str-Rif double mutant (M6) of M1-94P. The structures of 1 and 2 were identified by analyzing extensive spectroscopic data. Compounds 1 and 2 both inhibit the proliferation of human lung fibroblasts (WI26), and 1 exhibits better anti-fibrotic activity than xiamenmycin. Our study presents the novel bioactive compounds isolated from S. xiamenensis mutant strain M6 constructed by ribosome engineering, which could be a useful approach in the discovery of new anti-fibrotic compounds.
Assuntos
Benzopiranos/química , Sedimentos Geológicos/química , Sedimentos Geológicos/microbiologia , Streptomyces/química , Streptomyces/genética , Benzopiranos/farmacologia , Fibroblastos/efeitos dos fármacos , Fibrose/tratamento farmacológico , Humanos , Pulmão/efeitos dos fármacos , Mutação/genética , Ribossomos/genética , Treonina/análogos & derivados , Treonina/química , Treonina/farmacologiaRESUMO
An anti-fibrotic compound produced by Streptomycesn xiamenensis, found in mangrove sediments, was investigated for possible therapeutic effects against fibrosis. The compound, N-[[3,4-dihydro-3S-hydroxy-2S-methyl-2-(4'R-methyl-3'S-pentenyl)-2H-1-benzopyran-6-yl]carbonyl]-threonine (1), was isolated from crude extracts and its structure, including the absolute configuration was determined by extensive spectroscopic data analyses, Mosher's method, Marfey's reagent and quantum mechanical calculations. In terms of biological effects, this compound inhibits the proliferation of human lung fibroblasts (WI26), blocks adhesion of human acute monocytic leukemia cells (THP-1) to a monolayer of WI26 cells, and reduces the contractile capacity of WI26 cells in three-dimensional free-floating collagen gels. Altogether, these data indicate that we have identified a bioactive alkaloid (1) with multiple inhibitory biological effects on lung excessive fibrotic characteristics, that are likely involved in fibrosis, suggesting that this molecule might indeed have therapeutic potential against fibrosis.
Assuntos
Benzopiranos/isolamento & purificação , Benzopiranos/farmacologia , Fibrose/tratamento farmacológico , Sedimentos Geológicos/microbiologia , Streptomyces/metabolismo , Árvores/microbiologia , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Colágeno/química , Fibroblastos/efeitos dos fármacos , Humanos , Hidrólise , Indicadores e Reagentes , Espectroscopia de Ressonância Magnética , Conformação Molecular , Streptomyces/crescimento & desenvolvimentoRESUMO
A better knowledge of the molecular process behind uterine corpus endometrial carcinoma (UCEC) is important for prognosis prediction and the development of innovative targeted gene therapies. The purpose of this research is to discover critical genes associated with UCEC. We analyzed the gene expression profiles of TCGA-UCEC and GSE17025, respectively, using Weighted Gene Co-expression Network Analysis (WGCNA) and differential gene expression analysis. From four sets of findings, a total of 95 overlapping genes were retrieved. On the 95 overlapping genes, KEGG pathway and GO enrichment analysis were conducted. Then, we mapped the PPI network of 95 overlapping genes using the STRING database. Twenty hub genes were evaluated using the Cytohubba plugin, including NR3C1, ATF3, KLF15, THRA, NR4A1, FOSB, PER3, HLF, NTRK3, EGR3, MAPK13, ARNTL2, PKM2, SCD, EIF5A, ADHFE1, RERGL, TUB, and ENC1. The expression levels of NR3C1, PKM2, and ENC1 were shown to be adversely linked with the survival time of UCEC patients using univariate Cox regression analysis and Kaplan-Meier survival calculation. ENC1 were also overexpressed in UCEC tumor tissues or cell lines, as shown by quantitative real-time PCR and Western blotting. Then we looked into it further and discovered that ENC1 expression was linked to tumor microenvironment and predicted various immunological checkpoints. In conclusion, our data indicate that ENC1 may be required for the development of UCEC and may serve as a future biomarker for diagnosis and therapy.
RESUMO
Preeclampsia (PE), presenting with onset hypertension and proteinuria, is a pregnancy-specific disorder that can result in maternal and fetal morbidity and mortality. Insufficient trophoblast invasion and migration has been considered to be an important cause of this disease. The present study aimed to investigate the role of peptidyl arginine deiminase 4 (PAD4), whose knockdown has been previously indicated to reduce inflammation and susceptibility to pregnancy loss in mice, in the development of PE in vitro. Lipopolysaccharide (LPS) was used to treat a human trophoblast cell line (HTR8/SVneo). After PAD4 silencing via transfection with short hairpin RNA against PAD4, the concentrations of inflammatory factors IL-6, IL-12 and monocyte chemoattractant protein (MCP)-1 were measured using ELISA. Cell viability was also measured using Cell Counting Kit-8 assay. HTR8/SVneo cell invasion and migration were detected using Transwell and wound healing assays, respectively. Western blotting was used to measure the expression of citrullinated NF-κB essential modulator (NEMO) and nuclear NF-κB p65 protein levels. TNF-α was applied for evaluating the potential regulatory effects of PAD4 on NF-κB in LPS-stimulated HTR8/SVneo cells. LPS increased the levels of IL-6, IL-12 and MCP-1 and reduced the migration and invasion of HTR8/SVneo cells. PAD4-knockdown was found to markedly reduce the levels of IL-6, IL-12 and MCP-1 secretion. HTR8/SVneo cell invasion and migration was also significantly elevated after PAD4 silencing following LPS exposure. In addition, LPS stimulation notably upregulated the protein levels of citrullinated NEMO and nuclear NF-κB p65, which was restored by PAD4 knockdown. Furthermore, TNF-α treatment partially counteracted the effects of PAD4 knockdown on the secretion of IL-6, MCP-1 and IL-12, which are markers of inflammation, and invasion and migration in LPS-induced HTR8/SVneo cells. To conclude, these results suggest that PAD4 silencing can suppress inflammation whilst promoting invasion and migration by trophoblast cells through inhibiting the NEMO/NF-κB pathway. These findings furthered the understanding in the complex molecular mechanism that can trigger PE and provide a promising target for the treatment of this disease.