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1.
Bioorg Chem ; 147: 107364, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38636434

RESUMO

Osteoporosis is particularly prevalent among postmenopausal women and the elderly. In the present study, we investigated the effect of the novel small molecule E0924G (N-(4-methoxy-pyridine-2-yl)-5-methylfuran-2-formamide) on osteoporosis. E0924G significantly increased the protein expression levels of osteoprotegerin (OPG) and runt-related transcription factor 2 (RUNX2), and thus significantly promoted osteogenesis in MC3T3-E1 cells. E0924G also significantly decreased osteoclast differentiation and inhibited bone resorption and F-actin ring formation in receptor activator of NF-κB ligand (RANKL)-induced osteoclasts from RAW264.7 macrophages. Importantly, oral administration of E0924G in both ovariectomized (OVX) rats and SAMP6 senile mice significantly increased bone mineral density and decreased bone loss compared to OVX controls or SAMR1 mice. Further mechanistic studies showed that E0924G could bind to and then activate peroxisome proliferator-activated receptor delta (PPARδ), and the pro-osteoblast effect and the inhibition of osteoclast differentiation induced by E0924G were significantly abolished when PPARδ was knocked down or inhibited. In conclusion, these data strongly suggest that E0924G has the potential to prevent OVX-induced and age-related osteoporosis by dual regulation of bone formation and bone resorption through activation of the PPARδ signaling pathway.


Assuntos
Reabsorção Óssea , Osteogênese , Ovariectomia , PPAR delta , Transdução de Sinais , Animais , Camundongos , Reabsorção Óssea/tratamento farmacológico , Reabsorção Óssea/prevenção & controle , Reabsorção Óssea/metabolismo , Ratos , PPAR delta/metabolismo , Feminino , Osteogênese/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Relação Estrutura-Atividade , Estrutura Molecular , Células RAW 264.7 , Osteoporose/tratamento farmacológico , Osteoporose/prevenção & controle , Osteoporose/metabolismo , Relação Dose-Resposta a Droga , Bibliotecas de Moléculas Pequenas/farmacologia , Bibliotecas de Moléculas Pequenas/química , Ratos Sprague-Dawley , Osteoclastos/efeitos dos fármacos , Osteoclastos/metabolismo , Diferenciação Celular/efeitos dos fármacos
2.
Pharmaceuticals (Basel) ; 17(4)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38675387

RESUMO

Aberrant epigenetic modifications are fundamental contributors to the pathogenesis of various cancers. Consequently, targeting these aberrations with small molecules, such as histone deacetylase (HDAC) inhibitors and DNA methyltransferase (DNMT) inhibitors, presents a viable strategy for cancer therapy. The objective of this study is to assess the anti-cancer efficacy of trichostatin C (TSC), an analogue of trichostatin A sourced from the fermentation of Streptomyces sp. CPCC 203909. Our investigations reveal that TSC demonstrates potent activity against both human lung cancer and urothelial bladder cancer cell lines, with IC50 values in the low micromolar range. Moreover, TSC induces apoptosis mediated by caspase 3/7 and arrests the cell cycle at the G2/M phase. When combined with the DNMT inhibitor decitabine, TSC exhibits a synergistic anti-cancer effect. Additionally, protein analysis elucidates a significant reduction in the expression of the tyrosine kinase receptor Axl. Notably, elevated concentrations of TSC correlate with the up-regulation of the transcription factor forkhead box class O1 (FoxO1) and increased levels of the proapoptotic proteins Bim and p21. In conclusion, our findings suggest TSC as a promising anti-cancer agent with HDAC inhibitory activity. Furthermore, our results highlight the potential utility of TSC in combination with DNMT inhibitors for cancer treatment.

3.
Cell Rep ; 43(3): 113865, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38412096

RESUMO

Microbial metabolites that can modulate neurodegeneration are promising therapeutic targets. Here, we found that the short-chain fatty acid propionate protects against α-synuclein-induced neuronal death and locomotion defects in a Caenorhabditis elegans model of Parkinson's disease (PD) through bidirectional regulation between the intestine and neurons. Both depletion of dietary vitamin B12, which induces propionate breakdown, and propionate supplementation suppress neurodegeneration and reverse PD-associated transcriptomic aberrations. Neuronal α-synuclein aggregation induces intestinal mitochondrial unfolded protein response (mitoUPR), which leads to reduced propionate levels that trigger transcriptional reprogramming in the intestine and cause defects in energy production. Weakened intestinal metabolism exacerbates neurodegeneration through interorgan signaling. Genetically enhancing propionate production or overexpressing metabolic regulators downstream of propionate in the intestine rescues neurodegeneration, which then relieves mitoUPR. Importantly, propionate supplementation suppresses neurodegeneration without reducing α-synuclein aggregation, demonstrating metabolic rescue of neuronal proteotoxicity downstream of protein aggregates. Our study highlights the involvement of small metabolites in the gut-brain interaction in neurodegenerative diseases.


Assuntos
Doença de Parkinson , alfa-Sinucleína , Animais , alfa-Sinucleína/metabolismo , Caenorhabditis elegans/metabolismo , Animais Geneticamente Modificados/metabolismo , Propionatos/farmacologia , Propionatos/metabolismo , Doença de Parkinson/metabolismo , Neurônios/metabolismo , Suplementos Nutricionais , Intestinos , Modelos Animais de Doenças , Neurônios Dopaminérgicos/metabolismo
4.
J Nat Prod ; 86(3): 604-611, 2023 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-36693727

RESUMO

Altersteroids A-D (1-4), four new 9,11-secosteroid-derived γ-lactones, were isolated from cultures of the ascomycete fungus Alternaria sp. Their structures were elucidated primarily by NMR experiments. The absolute configuration of 1 was established by X-ray crystallographic analysis of its di-p-nitrobenzenesulfonate 1a using Cu Kα radiation, whereas those for 2-4 were assigned by quantum-chemical calculations. Compounds 1-4 incorporate a γ-lactone moiety fused to the steroid D ring at C-13/C-14. Compound 3 showed moderate cytotoxicity toward four tumor cell lines and induced an apoptotic process in A549 cells. Notably, compound 3 showed equipotent activity against the cisplatin-sensitive MB49 and -resistant MB49 CisR cells, with an IC50 value of 12.7 µM.


Assuntos
Ascomicetos , Secoesteroides , Alternaria/química , Lactonas/química , Estrutura Molecular , Ascomicetos/química , Linhagem Celular Tumoral
5.
Int J Mol Sci ; 23(21)2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36362263

RESUMO

Krüppel-like factor 2 (KLF2) is an atherosclerotic protective transcription factor that maintains endothelial cell homeostasis through its anti-inflammatory, anti-oxidant, and antithrombotic properties. The aim of this study was to discover KLF2 activators from microbial secondary metabolites and explore their potential molecular mechanisms. By using a high-throughput screening model based on a KLF2 promoter luciferase reporter assay, column chromatography, electrospray ionization mass spectrometry (ESI-MS), and nuclear magnetic resonance (NMR) spectra, trichostatin D (TSD) was isolated from the rice fermentation of Streptomyces sp. CPCC203909 and identified as a novel KLF2 activator. Real-time-quantitative polymerase chain reaction (RT-qPCR) results showed that TSD upregulated the mRNA level of KLF2 in endothelial cells. Functional assays showed that TSD attenuated monocyte adhesion to endothelial cells, decreased vascular cell adhesion protein 1 (VCAM-1) and intercellular adhesion molecule 1 (ICAM-1) expression, and exhibited an anti-inflammatory effect in tumor necrosis factor alpha (TNFα)-induced endothelial cells. We further demonstrated through siRNA and western blot assays that the effects of TSD on monocyte adhesion and inflammation in endothelial cells were partly dependent on upregulating KLF2 expression and then inhibiting the NOD-like receptor protein 3 (NLRP3)/Caspase-1/interleukin-1beta (IL-1ß) signaling pathway. Furthermore, histone deacetylase (HDAC) overexpression and molecular docking analysis results showed that TSD upregulated KLF2 expression by inhibiting HDAC 4, 5, and 7 activities. Taken together, TSD was isolated from the fermentation of Streptomyces sp. CPCC203909 and first reported as a potential activator of KLF2 in this study. Furthermore, TSD upregulated KLF2 expression by inhibiting HDAC 4, 5, and 7 and attenuated endothelial inflammation via regulation of the KLF2/NLRP3/Caspase-1/IL-1ß signaling pathway.


Assuntos
Células Endoteliais , Fator de Necrose Tumoral alfa , Humanos , Fator de Necrose Tumoral alfa/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Células Endoteliais/metabolismo , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Simulação de Acoplamento Molecular , Inflamação/patologia , Molécula 1 de Adesão de Célula Vascular/metabolismo , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/metabolismo , Caspases/metabolismo
6.
J Biol Chem ; 298(8): 102258, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35839853

RESUMO

Bacteria adapt to their constantly changing environments largely by transcriptional regulation through the activities of various transcription factors (TFs). However, techniques that monitor TF-promoter interactions in situ in living bacteria are lacking. Herein, we developed a whole-cell TF-promoter binding assay based on the intermolecular FRET between an unnatural amino acid, l-(7-hydroxycoumarin-4-yl) ethylglycine, which labels TFs with bright fluorescence through genetic encoding (donor fluorophore) and the live cell nucleic acid stain SYTO 9 (acceptor fluorophore). We show that this new FRET pair monitors the intricate TF-promoter interactions elicited by various types of signal transduction systems, including one-component (CueR) and two-component systems (BasSR and PhoPQ), in bacteria with high specificity and sensitivity. We demonstrate that robust CouA incorporation and FRET occurrence is achieved in all these regulatory systems based on either the crystal structures of TFs or their simulated structures, if 3D structures of the TFs were unavailable. Furthermore, using CueR and PhoPQ systems as models, we demonstrate that the whole-cell FRET assay is applicable for the identification and validation of complex regulatory circuit and novel modulators of regulatory systems of interest. Finally, we show that the FRET system is applicable for single-cell analysis and monitoring TF activities in Escherichia coli colonizing a Caenorhabditis elegans host. In conclusion, we established a tractable and sensitive TF-promoter binding assay, which not only complements currently available approaches for DNA-protein interactions but also provides novel opportunities for functional annotation of bacterial signal transduction systems and studies of the bacteria-host interface.


Assuntos
Transferência Ressonante de Energia de Fluorescência , Transdução de Sinais , Fatores de Transcrição , Animais , Caenorhabditis elegans/microbiologia , Escherichia coli/genética , Escherichia coli/metabolismo , Transferência Ressonante de Energia de Fluorescência/métodos , Interações entre Hospedeiro e Microrganismos/fisiologia , Compostos Orgânicos/metabolismo , Ligação Proteica , Análise de Célula Única/métodos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
7.
Front Pharmacol ; 13: 875349, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35571084

RESUMO

Emerging evidence from both clinical studies and animal models indicates the importance of the interaction between the gut microbiome and the brain in the pathogenesis of neurodegenerative diseases (NDs). Although how microbes modulate neurodegeneration is still mostly unclear, recent studies have started to probe into the mechanisms for the communication between microbes and hosts in NDs. In this review, we highlight the advantages of using Caenorhabditis elegans (C. elegans) to disentangle the microbe-host interaction that regulates neurodegeneration. We summarize the microbial pro- and anti-neurodegenerative factors identified using the C. elegans ND models and the effects of many are confirmed in mouse models. Specifically, we focused on the role of bacterial amyloid proteins, such as curli, in promoting proteotoxicity and neurodegeneration by cross-seeding the aggregation of endogenous ND-related proteins, such as α-synuclein. Targeting bacterial amyloid production may serve as a novel therapeutic strategy for treating NDs, and several compounds, such as epigallocatechin-3-gallate (EGCG), were shown to suppress neurodegeneration at least partly by inhibiting curli production. Because bacterial amyloid fibrils contribute to biofilm formation, inhibition of amyloid production often leads to the disruption of biofilms. Interestingly, from a list of 59 compounds that showed neuroprotective effects in C. elegans and mouse ND models, we found that about half of them are known to inhibit bacterial growth or biofilm formation, suggesting a strong correlation between the neuroprotective and antibiofilm activities. Whether these potential therapeutics indeed protect neurons from proteotoxicity by inhibiting the cross-seeding between bacterial and human amyloid proteins awaits further investigations. Finally, we propose to screen the long list of antibiofilm agents, both FDA-approved drugs and novel compounds, for their neuroprotective effects and develop new pharmaceuticals that target the gut microbiome for the treatment of NDs. To this end, the C. elegans ND models can serve as a platform for fast, high-throughput, and low-cost drug screens that target the microbe-host interaction in NDs.

8.
J Nat Prod ; 84(12): 3122-3130, 2021 12 24.
Artigo em Inglês | MEDLINE | ID: mdl-34846891

RESUMO

A new cytochalasin dimer, verruculoid A (1), three new cytochalasin derivatives, including 12-nor-cytochalasin F (2), 22-methoxycytochalasin B6 (3), and 19-hydroxycytochalasin B (4), and 20-deoxycytochalasin B (5), a synthetic product obtained as a natural product for the first time, together with four known analogues (6-9), were isolated and identified from the culture extract of Curvularia verruculosa CS-129, an endozoic fungus obtained from the inner fresh tissue of the deep-sea squat lobster Shinkaia crosnieri, which was collected from the cold seep area of the South China Sea. Structurally, verruculoid A (1) represents the first cytochalasin homodimer containing a thioether bridge, while 12-nor-cytochalasin F (2) is the first 12-nor-cytochalasin derivative. Their structures were elucidated by detailed interpretation of the NMR spectroscopic and mass spectrometric data. X-ray crystallographic analysis and ECD calculations confirmed their structures and absolute configurations. Compound 1 displayed activity against the human pathogenic bacterium Escherichia coli (MIC = 2 µg/mL), while compounds 4, 8, and 9 showed cytotoxicity against three tumor cell lines (HCT-116, HepG-2, and MCF-7) with IC50 values from 5.2 to 12 µM. The structure-activity relationship was briefly discussed.


Assuntos
Temperatura Baixa , Crustáceos/química , Curvularia/isolamento & purificação , Citocalasinas/farmacologia , Ecossistema , Animais , Citocalasinas/química , Citocalasinas/isolamento & purificação
9.
Bioorg Chem ; 116: 105361, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34562672

RESUMO

The OPG/RANKL/RANK pathway is a promising target for the design of therapeutic agents used in the treatment of osteoporosis. E09241 with an N-methylpyridine-chlorofuranformamide structural skeleton was previously identified to decrease bone loss and thus protect against osteoporosis in ovariectomized rats through increasing osteoprotegerin (OPG) expression. In this study, 36 derivatives of E09241 (3a) were prepared. The synthesis, up-regulation of OPG activities, SAR (structure-activity relationship), and cytotoxicity of these compounds are presented. Compounds with good up-regulating OPG activities could inhibit RANKL (the receptor activator of nuclear factor-kappa B ligand)-induced osteoclastogenesis in RAW264.7 cells. Particularly, compounds 3c and 3i1 significantly reduced NFATc1 and MMP-9 protein expression through inhibition of the NF-κB and MAPK pathways in RANKL induced RAW264.7 cells. In addition, compounds 3c and 3v significantly promoted osteoblast differentiation in MC3T3-E1 cells in osteogenic medium, and compounds 3c, 3v, and 3i1 obviously increased OPG protein expression and secretion in MC3T3-E1 cells. Furthermore, the pharmacokinetic profiles, acute toxicity, and hERG K+ channel effects of compounds 3a, 3c, 3e, 3v, and 3i1 were investigated. Taken together, these results indicate that N-methylpyridine-chlorofuranformamide analog 3i1 could serve as a promising lead for the development of new agents for treating osteoporosis.


Assuntos
Formamidas/farmacologia , Furanos/farmacologia , Osteoprotegerina/metabolismo , Piridinas/farmacologia , Ligante RANK/antagonistas & inibidores , Células 3T3 , Animais , Relação Dose-Resposta a Droga , Formamidas/química , Furanos/química , Camundongos , Estrutura Molecular , Osteogênese/efeitos dos fármacos , Piridinas/química , Ligante RANK/metabolismo , Células RAW 264.7 , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade
10.
Proc Natl Acad Sci U S A ; 118(34)2021 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34413194

RESUMO

Growing evidence indicates that gut microbiota play a critical role in regulating the progression of neurodegenerative diseases such as Parkinson's disease. The molecular mechanism underlying such microbe-host interaction is unclear. In this study, by feeding Caenorhabditis elegans expressing human α-syn with Escherichia coli knockout mutants, we conducted a genome-wide screen to identify bacterial genes that promote host neurodegeneration. The screen yielded 38 genes that fall into several genetic pathways including curli formation, lipopolysaccharide assembly, and adenosylcobalamin synthesis among others. We then focused on the curli amyloid fibril and found that genetically deleting or pharmacologically inhibiting the curli major subunit CsgA in E. coli reduced α-syn-induced neuronal death, restored mitochondrial health, and improved neuronal functions. CsgA secreted by the bacteria colocalized with α-syn inside neurons and promoted α-syn aggregation through cross-seeding. Similarly, curli also promoted neurodegeneration in C. elegans models of Alzheimer's disease, amyotrophic lateral sclerosis, and Huntington's disease and in human neuroblastoma cells.


Assuntos
Amiloide/química , Proteínas de Escherichia coli/metabolismo , Escherichia coli/fisiologia , Genoma Bacteriano , Interações entre Hospedeiro e Microrganismos , Doenças Neurodegenerativas/patologia , alfa-Sinucleína/metabolismo , Animais , Biofilmes/crescimento & desenvolvimento , Caenorhabditis elegans , Proteínas de Escherichia coli/genética , Estudo de Associação Genômica Ampla , Humanos , Doenças Neurodegenerativas/etiologia , Doenças Neurodegenerativas/metabolismo , alfa-Sinucleína/química , alfa-Sinucleína/genética
11.
Cancers (Basel) ; 12(2)2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32028599

RESUMO

Occurrence of cisplatin-resistance in bladder cancer is frequent and results in disease progression. Thus, novel therapeutic approaches are a high medical need for patients suffering from chemotherapy failure. The purpose of this study was to test the combination of the DNA methyltransferase inhibitor decitabine (DAC) with the histone deacetylase inhibitor entinostat (ENT) in bladder cancer cells with different platinum sensitivities: J82, cisplatin-resistant J82CisR, and RT-112. Intermittent treatment of J82 cells with cisplatin resulted in the six-fold more cisplatin-resistant cell line J82CisR. Combinations of DAC and/or ENT plus cisplatin could not reverse chemoresistance. However, the combination of DAC and ENT acted cytotoxic in a highly synergistic manner as shown by Chou-Talalay analysis via induction of apoptosis and cell cycle arrest. Importantly, this effect was cancer cell-selective as no synergism was found for the combination in the non-cancerous urothelial cell line HBLAK. Expression analysis indicated that epigenetic treatment led to up-regulation of forkhead box class O1 (FoxO1) and further activated proapoptotic Bim and the cell cycle regulator p21 and reduced expression of survivin in J82CisR. In conclusion, the combination of DAC and ENT is highly synergistic and has a promising potential for therapy of bladder cancer, particularly in cases with platinum resistance.

12.
Front Pharmacol ; 11: 532568, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33442380

RESUMO

Phenethyl isothiocyanate is widely present in cruciferous vegetables with multiple biological effects. Here we reported the antiatherogenic effects and the underlying mechanisms of JC-5411 (Phenethyl isothiocyanate formulation) in vitro and in vivo. Luciferase reporter assay showed that JC-5411 increased the activity of nuclear factor erythroid 2-related factor 2 (Nrf2) and antioxidant response element (ARE). JC-5411 treatment significantly increased the protein expression of Nrf2 and its downstream target gene hemeoxygenase 1 (HO-1) in liver of apolipoprotein E deficient (ApoE-/-) mice. Importantly, JC-5411 treatment significantly reduced atherosclerotic plaque area in both en face aorta and aortic sinus when compared with model group in WD induced ApoE-/- mice. JC-5411 obviously decreased proinflammatory factors' levels in serum of ApoE-/- mice, LPS stimulated macrophages and TNFα induced endothelial cells, respectively. JC-5411 significantly decreased the levels of total cholesterol (TC) and triglyceride (TG) in both serum and liver of ApoE-/- mice and hyperlipidemic golden hamsters. Mechanism studies showed that JC-5411 exerted anti-inflammatory effect through activating Nrf2 signaling and inhibiting NF-κB and NLRP3 inflammasome pathway. JC-5411 exerted regulating lipid metabolism effect through increasing cholesterol transfer proteins (ABCA1 and LDLR) expression, regulating fatty acids synthesis related genes (p-ACC, SCD1 and FAS), and increasing fatty acids ß-oxidation (CPT1A) in vivo. Furthermore, JC-5411 treatment had a favorable antioxidant effect in ApoE-/- mice by increasing the antioxidant related genes expression. Taken together, we conclude that JC-5411 as a Nrf2 activator has anti-inflammatory, rebalancing lipid metabolism, and antioxidant effects, which makes it as a potential therapeutic agent against atherosclerosis.

13.
Bioorg Med Chem ; 28(1): 115108, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31787463

RESUMO

Although histone deacetylase inhibitors (HDACi) have shown promising antitumor effects in specific types of blood cancer, their effects on solid tumors are limited. Previously, we developed LMK235 (5), a class I and class IIb preferential HDACi with chemosensitizing effects on breast cancer, ovarian cancer and HNSCC. Based on its promising effects on solid tumor cells, we modified the cap group of 5 to improve its anticancer activity. The tri- and dimethoxy-phenyl substituted compounds 13a and 13d turned out to be the most potent HDAC inhibitors of this study. The isoform profiling revealed a dual HDAC2/HDAC6 inhibition profile, which was confirmed by the acetylation of α-tubulin and histone H3 in Cal27 and Cal27CisR. In combination with cisplatin, both compounds enhanced the cisplatin-induced cytotoxicity via caspase-3/7 activation. The effect was more pronounced in the cisplatin resistant subline Cal27CisR. The pretreatment with 13d resulted in a complete resensitisation of Cal27CisR with IC50 values in the range of the parental cell line. Therefore, 13d may serve as an epigenetic tool to analyze and modulate the cisplatin resistance of solid tumors.


Assuntos
Amidas/farmacologia , Antineoplásicos/farmacologia , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Histona Desacetilases/metabolismo , Amidas/síntese química , Amidas/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores de Histona Desacetilases/síntese química , Inibidores de Histona Desacetilases/química , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Relação Estrutura-Atividade
14.
Bioorg Med Chem ; 27(19): 115044, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31443950

RESUMO

Platinum compounds are the first-line therapy for many types of cancer. However, drug resistance has frequently been reported for and is a major limitation of platinum-based chemotherapy in the clinic. In the current study, we examined the anti-tumor activity of phomoxanthone A (PXA), a tetrahydroxanthone dimer isolated from the endophytic fungus Phomopsis longicolla, in several solid cancer cell lines and their cisplatin-resistant sub-cell lines. PXA showed strong cytotoxic effects with IC50 values in the high nanomolar or low micromolar range in MTT assays. IC50 values of PXA were lower than those of cisplatin. Remarkably, equipotent anti-cancer activity was found in cisplatin-sensitive and respective cisplatin-resistant cells. Anticancer effects of PXA were studied in further detail in ovarian cancer (A2780) and bladder cancer (J82) cell pairs. PXA led to rapid depolarization of the mitochondrial membrane potential and strong activation of caspase 3 and 7, eventually resulting in strong induction of apoptosis. These effects occurred again both in sensitive and resistant cell lines. IC50 values of PXA from MTT and mitochondrial membrane depolarization assays were in good agreement. Configurational free energy computations indicate that both the neutral and singly negatively charged PXA show membrane partitioning and can penetrate the inner mitochondrial membrane. PXA treatment did not damage the plasma membranes of cancer cells, thus excluding unspecific membrane effects. Further, PXA had neither an effect on intracellular ROS nor on reduction of ROS after hydrogen peroxide treatment. In conclusion, our studies present PXA as a natural compound with strong apoptotic anticancer effects against platinum-resistant solid cancers. This may open new treatment options in clinically resistant malignancies.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Xantonas/farmacologia , Cálcio/metabolismo , Caspase 3/metabolismo , Caspase 7/metabolismo , Linhagem Celular Tumoral , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos
15.
Fitoterapia ; 137: 104249, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31247219

RESUMO

Two azaphilone pigments (1 and 2), two dihydrobenzofurans (3 and 4), two macrodiolides (5 and 6), and a dimeric alkyl aromatic constituent (7) were isolated from the goose dung-derived fungus Coniella fragariae. Compounds 1-3 proved to be new natural products. Coniellins H and I (1 and 2) feature a tetracyclic core and an aldehyde group at C-5, which is unusual for azaphilone derivatives. The X-ray structure of pyrenophorin (5) is reported for the first time. Pyrenophorin (5) showed strong cytotoxicity against several cancer cell lines with IC50 values ranging from 0.07 to 7.8 µM.


Assuntos
Ascomicetos/química , Benzopiranos/farmacologia , Pigmentos Biológicos/farmacologia , Animais , Benzofuranos/isolamento & purificação , Benzopiranos/isolamento & purificação , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Fezes/microbiologia , Gansos/microbiologia , Alemanha , Humanos , Estrutura Molecular , Mar do Norte , Pigmentos Biológicos/isolamento & purificação
16.
J Nat Prod ; 82(6): 1412-1423, 2019 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-31117519

RESUMO

A chemical investigation of the endophyte Penicillium sp. (strain ZO-R1-1), isolated from roots of the medicinal plant Zingiber officinale, yielded nine new indole diterpenoids (1-9), together with 13 known congeners (10-22). The structures of the new compounds were elucidated by 1D and 2D NMR analysis in combination with HRESIMS data. The absolute configuration of the new natural products 1, 3, and 7 was determined using the TDDFT-ECD approach and confirmed for 1 by single-crystal X-ray determination through anomalous dispersion. The isolated compounds were tested for cytotoxicity against L5178Y, A2780, J82, and HEK-293 cell lines. Compound 1 was the most active metabolite toward L5178Y cells, with an IC50 value of 3.6 µM, and an IC50 against A2780 cells of 8.7 µM. Interestingly, 1 features a new type of indole diterpenoid scaffold with a rare 6/5/6/6/6/6/5 heterocyclic system bearing an aromatic ring C, which is suggested to be important for the cytotoxic activity of this natural product against L5278Y and A2780 cells.


Assuntos
Antineoplásicos/química , Produtos Biológicos/química , Diterpenos/química , Endófitos/química , Indóis/química , Neoplasias Ovarianas/tratamento farmacológico , Penicillium/química , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Produtos Biológicos/isolamento & purificação , Produtos Biológicos/farmacologia , Produtos Biológicos/uso terapêutico , Linhagem Celular Tumoral , Feminino , Células HEK293 , Humanos , Espectroscopia de Ressonância Magnética , Penicillium/metabolismo
17.
Clin Epigenetics ; 10(1): 100, 2018 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-30064501

RESUMO

BACKGROUND: Histone deacetylase inhibitors (HDACi) are promising anti-cancer drugs that could also be employed for urothelial carcinoma (UC) therapy. It is unclear, however, whether inhibition of all 11 zinc-dependent HDACs or of individual enzymes is more efficacious and specific. Here, we investigated the novel HDACi 19i (LMK235) with presumed preferential activity against class IIA HDAC4/5 in comparison to the pan-HDACi vorinostat (SAHA) and the HDAC4-specific HDACi TMP269 in UC cell lines with basal expression of HDAC4 and characterized two HDAC4-overexpressing UC cell lines. METHODS: Cytotoxic concentrations 50% (CC50s) for HDACi were determined by MTT assay and high-content analysis-based fluorescent live/dead assay in UC cell lines with different expression of HDAC4 and as well as in normal urothelial cell cultures, HBLAK and HEK-293 cell lines. Effects of HDACis were analyzed by flow cytometry; molecular changes were followed by qRT-PCR and Western blots. UC lines overexpressing HDAC4 were established by lentiviral transduction. Inhibitor activity profiles of HDACi were obtained by current state in vitro assays, and docking analysis was performed using an updated crystal structure of HDAC4. RESULTS: In UC cell lines, 19i CC50s ranged around 1 µM; control lines were similarly or less sensitive. Like SAHA, 19i increased the G2/M-fraction, disturbed mitosis, and elicited apoptosis or in some cells senescence. Thymidylate synthase expression was diminished, and p21CIP1 was induced; global histone acetylation and α-tubulin acetylation also increased. In most cell lines, 19i as well as SAHA induced HDAC5 and HDAC4 mRNAs while rather repressing HDAC7. UC cell lines overexpressing HDAC4 were not significantly less sensitive to 19i. Reevaluation of the in vitro HDAC isoenzyme activity inhibition profile of 19i and its docking to HDAC4 using current assays suggested rather low activity against class IIA HDACs. The specific class IIA HDAC inhibitor TMP269 impeded proliferation of UC cell lines only at concentrations > 10 µM. CONCLUSIONS: Anti-neoplastic effects of 19i on UC cells appear to be exerted by targeting class I HDACs. In fact, HDAC4 may rather impede UC growth. Our results suggest that targeting of class IIA HDACs 4/5 may not be optimal for UC therapy. Moreover, our investigation provides further evidence for cross-regulation of class IIA HDACs by class I HDACs.


Assuntos
Carcinoma de Células de Transição/genética , Inibidores de Histona Desacetilases/farmacologia , Histona Desacetilases/genética , Neoplasias da Bexiga Urinária/genética , Vorinostat/farmacologia , Carcinoma de Células de Transição/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Metilação de DNA , Ensaios de Seleção de Medicamentos Antitumorais , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HEK293 , Inibidores de Histona Desacetilases/química , Histona Desacetilases/química , Humanos , Simulação de Acoplamento Molecular , Neoplasias da Bexiga Urinária/tratamento farmacológico , Vorinostat/química
18.
Neurobiol Dis ; 109(Pt A): 88-101, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28982592

RESUMO

Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by the presence of extracellular amyloid plaques consisting of Amyloid-ß peptide (Aß) aggregates and neurofibrillary tangles formed by aggregation of hyperphosphorylated microtubule-associated protein tau. We generated a novel invertebrate model of AD by crossing Aß1-42 (strain CL2355) with either pro-aggregating tau (strain BR5270) or anti-aggregating tau (strain BR5271) pan-neuronal expressing transgenic Caenorhabditis elegans. The lifespan and progeny viability of the double transgenic strains were significantly decreased compared with wild type N2 (P<0.0001). In addition, co-expression of these transgenes interfered with neurotransmitter signaling pathways, caused deficits in chemotaxis associative learning, increased protein aggregation visualized by Congo red staining, and increased neuronal loss. Global transcriptomic RNA-seq analysis revealed 248 up- and 805 down-regulated genes in N2 wild type versus Aß1-42+pro-aggregating tau animals, compared to 293 up- and 295 down-regulated genes in N2 wild type versus Aß1-42+anti-aggregating tau animals. Gene set enrichment analysis of Aß1-42+pro-aggregating tau animals uncovered up-regulated annotation clusters UDP-glucuronosyltransferase (5 genes, P<4.2E-4), protein phosphorylation (5 genes, P<2.60E-02), and aging (5 genes, P<8.1E-2) while the down-regulated clusters included nematode cuticle collagen (36 genes, P<1.5E-21). RNA interference of 13 available top up-regulated genes in Aß1-42+pro-aggregating tau animals revealed that F-box family genes and nep-4 could enhance life span deficits and chemotaxis deficits while Y39G8C.2 (TTBK2) could suppress these behaviors. Comparing the list of regulated genes from C. elegans to the top 60 genes related to human AD confirmed an overlap of 8 genes: patched homolog 1, PTCH1 (ptc-3), the Rab GTPase activating protein, TBC1D16 (tbc-16), the WD repeat and FYVE domain-containing protein 3, WDFY3 (wdfy-3), ADP-ribosylation factor guanine nucleotide exchange factor 2, ARFGEF2 (agef-1), Early B-cell Factor, EBF1 (unc-3), d-amino-acid oxidase, DAO (daao-1), glutamate receptor, metabotropic 1, GRM1 (mgl-2), prolyl 4-hydroxylase subunit alpha 2, P4HA2 (dpy-18 and phy-2). Taken together, our C. elegans double transgenic model provides insight on the fundamental neurobiologic processes underlying human AD and recapitulates selected transcriptomic changes observed in human AD brains.


Assuntos
Doença de Alzheimer/genética , Peptídeos beta-Amiloides/genética , Comportamento Animal , Caenorhabditis elegans/genética , Modelos Animais de Doenças , Expressão Gênica , Fragmentos de Peptídeos/genética , Proteínas tau/genética , Animais , Animais Geneticamente Modificados , Proteínas de Caenorhabditis elegans/genética , Humanos , Análise de Sobrevida
19.
J Nat Prod ; 80(1): 162-168, 2017 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-27992187

RESUMO

Five new polyhydroxylated hydroanthraquinone derivatives, namely, 8-hydroxyconiothyrinone B (1), 8,11-dihydroxyconiothyrinone B (2), 4R,8-dihydroxyconiothyrinone B (3), 4S,8-dihydroxyconiothyrinone B (4), and 4S,8-dihydroxy-10-O-methyldendryol E (5), were isolated and identified from the culture extract of Talaromyces islandicus EN-501, an endophytic fungus obtained from the inner tissue of the marine red alga Laurencia okamurai. The structures of these compounds were established on the basis of detailed interpretation of their NMR and mass spectroscopic data, and the structures and absolute configurations of compounds 1 and 2 were confirmed by X-ray crystallographic analysis, while the absolute configurations of compounds 3-5 were determined by TDDFT calculations of the ECD spectra. The antimicrobial, antioxidant, and cytotoxic activities of compounds 1-5 were evaluated.


Assuntos
Antraquinonas/isolamento & purificação , Anti-Infecciosos/isolamento & purificação , Antraquinonas/química , Antraquinonas/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antioxidantes , Cristalografia por Raios X , Laurencia , Espectroscopia de Ressonância Magnética , Biologia Marinha , Testes de Sensibilidade Microbiana , Estrutura Molecular , Talaromyces
20.
Org Lett ; 18(20): 5304-5307, 2016 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-27723361

RESUMO

Four new diketopiperazines including spirobrocazines A-C (1-3) and brocazine G (4) were characterized from the mangrove-derived Penicillium brocae MA-231. Compounds 1 and 2 had a 6/5/6/5/6 cyclic system with a rare spirocyclic center at C-2. Their structures and absolute configurations were determined by spectroscopic analysis, TDDFT-ECD calculations, and X-ray diffraction. Compound 4 exhibited potent cytotoxicity against both sensitive and cisplatin-resistant human ovarian cancer cells and strong antimicrobial activity against pathogenic Staphylococcus aureus.

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