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1.
Anticancer Res ; 38(6): 3299-3307, 2018 Jun.
Article in English | MEDLINE | ID: mdl-29848677

ABSTRACT

BACKGROUND: Prostate cancer presents the highest incidence rates among all cancers in men. Hapalindole H (Hap H), isolated from Fischerella muscicola (UTEX strain number LB1829) as part of our natural product anticancer drug discovery program, was found to be significantly active against prostate cancer cells. MATERIALS AND METHODS: In this study, Hap H was tested for nuclear factor-kappa B (NF-ĸB) inhibition and selective cytotoxic activity against different cancer cell lines. The apoptotic effect was assessed on PC-3 prostate cancer cells by fluorescence-activated cell sorting analysis. The underlying mechanism that induced apoptosis was studied and the effect of Hap H on mitochondria was evaluated and characterized using western blot and flow cytometric analysis. RESULTS: Hap H was identified as a potent NF-ĸB inhibitor (0.76 µM) with selective cytotoxicity against the PC-3 prostate cancer cell line (0.02 µM). The apoptotic effect was studied on PC-3 cells. The results showed that treatment of PC-3 cells with Hap H reduced the formation of NAD(P)H, suggesting that the function of the outer mitochondrial membrane was negatively affected. Thus, the mitochondrial transmembrane potential was assessed in Hap H treated cells. The results showed that the outer mitochondrial membrane was disrupted as an increased amount of JC-1 monomers were detected in treated cells (78.3%) when compared to untreated cells (10.1%), also suggesting that a large number of treated cells went into an apoptotic state. CONCLUSION: Hap H was found to have potent NF-ĸB p65-inhibitory activity and induced apoptosis through the intrinsic mitochondrial pathway in hormone-independent PC-3 prostate cancer cells.


Subject(s)
Apoptosis/drug effects , Indole Alkaloids/pharmacology , Mitochondria/drug effects , NF-kappa B/antagonists & inhibitors , Signal Transduction/drug effects , Cell Line, Tumor , HT29 Cells , Humans , Indole Alkaloids/chemistry , Intercellular Adhesion Molecule-1/metabolism , MCF-7 Cells , Male , Membrane Potential, Mitochondrial/drug effects , Mitochondria/metabolism , Molecular Structure , NF-kappa B/metabolism , Prostatic Neoplasms, Castration-Resistant/metabolism , Prostatic Neoplasms, Castration-Resistant/pathology
2.
Am J Physiol Gastrointest Liver Physiol ; 311(5): G903-G919, 2016 11 01.
Article in English | MEDLINE | ID: mdl-27659423

ABSTRACT

Knockout technology has proven useful for delineating functional roles of specific genes. Here we describe and provide an explanation for striking pathology that occurs in a subset of genetically engineered mice expressing a rat CaVß2a transgene under control of the cardiac α-myosin heavy chain promoter. Lesions were limited to mice homozygous for transgene and independent of native Cacnb2 genomic copy number. Gross findings included an atrophied pancreas; decreased adipose tissue; thickened, orange intestines; and enlarged liver, spleen, and abdominal lymph nodes. Immune cell infiltration and cell engulfment by macrophages were associated with loss of pancreatic acinar cells. Foamy macrophages diffusely infiltrated the small intestine's lamina propria, while similar macrophage aggregates packed liver and splenic red pulp sinusoids. Periodic acid-Schiff-positive, diastase-resistant, iron-negative, Oil Red O-positive, and autofluorescent cytoplasm was indicative of a lipid storage disorder. Electron microscopic analysis revealed liver sinusoids distended by clusters of macrophages containing intracellular myelin "swirls" and hepatocytes with enlarged lysosomes. Additionally, build up of cholesterol, cholesterol esters, and triglycerides, along with changes in liver metabolic enzyme levels, were consistent with a lipid processing defect. Because of this complex pathology, we examined the transgene insertion site. Multiple transgene copies inserted into chromosome 19; at this same site, an approximate 180,000 base pair deletion occurred, ablating cholesterol 25-hydroxylase and partially deleting lysosomal acid lipase and CD95 Loss of gene function can account for the altered lipid processing, along with hypertrophy of the immune system, which define this phenotype, and serendipitously provides a novel mouse model of lysosomal storage disorder.


Subject(s)
Calcium Channels, L-Type/genetics , Cholesterol/metabolism , Lysosomal Storage Diseases/genetics , Triglycerides/metabolism , Animals , Disease Models, Animal , Hepatocytes/metabolism , Hepatocytes/pathology , Liver/metabolism , Liver/pathology , Lysosomal Storage Diseases/metabolism , Lysosomal Storage Diseases/pathology , Lysosomes/metabolism , Lysosomes/pathology , Macrophages/metabolism , Macrophages/pathology , Mice , Mice, Transgenic , Promoter Regions, Genetic , Spleen/metabolism , Spleen/pathology
3.
Cell Rep ; 15(11): 2438-48, 2016 06 14.
Article in English | MEDLINE | ID: mdl-27264171

ABSTRACT

The innate immune system is the first line of defense against Neisseria gonorrhoeae (GC). Exposure of cells to GC lipooligosaccharides induces a strong immune response, leading to type I interferon (IFN) production via TLR4/MD-2. In addition to living freely in the extracellular space, GC can invade the cytoplasm to evade detection and elimination. Double-stranded DNA introduced into the cytosol binds and activates the enzyme cyclic-GMP-AMP synthase (cGAS), which produces 2'3'-cGAMP and triggers STING/TBK-1/IRF3 activation, resulting in type I IFN expression. Here, we reveal a cytosolic response to GC DNA that also contributes to type I IFN induction. We demonstrate that complete IFN-ß induction by live GC depends on both cGAS and TLR4. Type I IFN is detrimental to the host, and dysregulation of iron homeostasis genes may explain lower bacteria survival in cGAS(-/-) and TLR4(-/-) cells. Collectively, these observations reveal cooperation between TLRs and cGAS in immunity to GC infection.


Subject(s)
Interferon Type I/metabolism , Neisseria gonorrhoeae/physiology , Nucleotidyltransferases/metabolism , Toll-Like Receptor 4/metabolism , Bacterial Secretion Systems , Cell Line , DNA, Bacterial/metabolism , Humans , Iron/metabolism , Membrane Proteins/metabolism , Microbial Viability , Nucleotides, Cyclic/metabolism , Transfection
4.
Psychoneuroendocrinology ; 70: 98-107, 2016 08.
Article in English | MEDLINE | ID: mdl-27209438

ABSTRACT

Neuroactive steroids (NAS) are allosteric modulators of the γ-aminobutyric acid (GABA) system. NAS and GABA are implicated in depression. The peripartum period involves physiologic changes in NAS which may be associated with peripartum depression and anxiety. We measured peripartum plasma NAS and GABA in healthy comparison subjects (HCS) and those at-risk for postpartum depression (AR-PPD) due to current mild depressive or anxiety symptoms or a history of depression. We evaluated 56 peripartum medication-free subjects. We measured symptoms with the Hamilton Depression Rating Scale (HAM-D17), Hamilton Anxiety Rating Scale (HAM-A) and Spielberger State-Trait Anxiety Inventory-State (STAI-S). Plasma NAS and GABA were quantified by liquid chromatography-mass spectrometry. We examined the associations between longitudinal changes in NAS, GABA and depressive and anxiety symptoms using generalized estimating equation methods. Peripartum GABA concentration was 1.9±0.7ng/mL (p=0.004) lower and progesterone and pregnanolone were 15.8±7.5 (p=0.04) and 1.5±0.7ng/mL (p=0.03) higher in AR-PPD versus HCS, respectively. HAM-D17 was negatively associated with GABA (ß=-0.14±0.05, p=0.01) and positively associated with pregnanolone (ß=0.16±0.06, p=0.01). STAI-S was positively associated with pregnanolone (ß=0.11±0.04, p=0.004), allopregnanolone (ß=0.13±0.05, p=0.006) and pregnenolone (ß=0.02±0.01, p=0.04). HAM-A was negatively associated with GABA (ß=-0.12±0.04, p=0.004) and positively associated with pregnanolone (ß=0.11±0.05, p=0.05). Altered peripartum NAS and GABA profiles in AR-PPD women suggest that their interaction may play an important role in the pathophysiology of peripartum depression and anxiety.


Subject(s)
Depression, Postpartum/blood , Steroids/blood , gamma-Aminobutyric Acid/blood , 20-alpha-Dihydroprogesterone/blood , Adult , Case-Control Studies , Desoxycorticosterone/blood , Female , Humans , Longitudinal Studies , Peripartum Period/physiology , Peripartum Period/psychology , Pregnancy , Pregnanolone/blood , Progesterone/blood , Receptors, GABA-A/blood , Risk Factors
5.
J Huntingtons Dis ; 4(2): 187-201, 2015.
Article in English | MEDLINE | ID: mdl-26397899

ABSTRACT

BACKGROUND: Huntington's disease (HD) is a neurodegenerative disease caused by a CAG expansion in the HD gene, which encodes the protein Huntingtin. Huntingtin associates with membranes and can interact directly with glycerophospholipids in membranes. OBJECTIVE: We analyzed glycerophospholipid profiles from brains of 11 month old wild-type (WT) and Q140/Q140 HD knock-in mice to assess potential changes in glycerophospholipid metabolism. METHODS: Polar lipids from cerebellum, cortex, and striatum were extracted and analyzed by liquid chromatography and negative ion electrospray tandem mass spectrometry analysis (LC-MS/MS). Gene products involved in polar lipid metabolism were studied using western blotting, immuno-electron microscopy and qPCR. RESULTS: Significant changes in numerous species of glycerophosphate (phosphatidic acid, PA) were found in striatum, cerebellum and cortex from Q140/Q140 HD mice compared to WT mice at 11 months. Changes in specific species could also be detected for other glycerophospholipids. Increases in species of lyso-PA (LPA) were measured in striatum of Q140/Q140 HD mice compared to WT. Protein levels for c-terminal binding protein 1 (CtBP1), a regulator of PA biosynthesis, were reduced in striatal synaptosomes from HD mice compared to wild-type at 6 and 12 months. Immunoreactivity for CtBP1 was detected on membranes of synaptic vesicles in striatal axon terminals in the globus pallidus. CONCLUSIONS: These novel results identify a potential site of molecular pathology caused by mutant Huntingtin that may impart early changes in HD.


Subject(s)
Brain/metabolism , Glycerophospholipids/metabolism , Huntington Disease/metabolism , Lysophospholipids/metabolism , Phosphatidic Acids/metabolism , Alcohol Oxidoreductases/metabolism , Animals , Brain/ultrastructure , Cerebellum/metabolism , Cerebral Cortex/metabolism , Corpus Striatum/metabolism , Corpus Striatum/ultrastructure , DNA-Binding Proteins/metabolism , Disease Models, Animal , Gene Knock-In Techniques , Huntingtin Protein , Huntington Disease/genetics , Male , Mass Spectrometry , Mice , Mice, Inbred C57BL , Nerve Tissue Proteins/genetics , Neurons/metabolism , Neurons/ultrastructure , Synaptic Vesicles/metabolism , Synaptic Vesicles/ultrastructure , Synaptosomes/metabolism
6.
J Nat Prod ; 77(6): 1473-87, 2014 Jun 27.
Article in English | MEDLINE | ID: mdl-24895010

ABSTRACT

The present study demonstrates the importance of adequate precision when reporting the δ and J parameters of frequency domain (1)H NMR (HNMR) data. Using a variety of structural classes (terpenoids, phenolics, alkaloids) from different taxa (plants, cyanobacteria), this study develops rationales that explain the importance of enhanced precision in NMR spectroscopic analysis and rationalizes the need for reporting Δδ and ΔJ values at the 0.1-1 ppb and 10 mHz level, respectively. Spectral simulations paired with iteration are shown to be essential tools for complete spectral interpretation, adequate precision, and unambiguous HNMR-driven dereplication and metabolomic analysis. The broader applicability of the recommendation relates to the physicochemical properties of hydrogen ((1)H) and its ubiquity in organic molecules, making HNMR spectra an integral component of structure elucidation and verification. Regardless of origin or molecular weight, the HNMR spectrum of a compound can be very complex and encode a wealth of structural information that is often obscured by limited spectral dispersion and the occurrence of higher order effects. This altogether limits spectral interpretation, confines decoding of the underlying spin parameters, and explains the major challenge associated with the translation of HNMR spectra into tabulated information. On the other hand, the reproducibility of the spectral data set of any (new) chemical entity is essential for its structure elucidation and subsequent dereplication. Handling and documenting HNMR data with adequate precision is critical for establishing unequivocal links between chemical structure, analytical data, metabolomes, and biological activity. Using the full potential of HNMR spectra will facilitate the general reproducibility for future studies of bioactive chemicals, especially of compounds obtained from the diversity of terrestrial and marine organisms.


Subject(s)
Cyanobacteria/chemistry , Magnetic Resonance Spectroscopy/methods , Metabolomics , Molecular Structure , Molecular Weight
7.
Lipids ; 48(9): 949-56, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23884629

ABSTRACT

Previous methods for the quantitative analysis of phytosterols have usually used GC-MS and require elaborate sample preparation including chemical derivatization. Other common methods such as HPLC with absorbance detection do not provide information regarding the identity of the analytes. To address the need for an assay that utilizes mass selectivity while avoiding derivatization, a quantitative method based on LC-tandem mass spectrometry (LC-MS-MS) was developed and validated for the measurement of six abundant dietary phytosterols and structurally related triterpene alcohols including brassicasterol, campesterol, cycloartenol, ß-sitosterol, stigmasterol, and lupeol in edible oils. Samples were saponified, extracted with hexane and then analyzed using reversed phase HPLC with positive ion atmospheric pressure chemical ionization tandem mass spectrometry and selected reaction monitoring. The utility of the LC-MS-MS method was demonstrated by analyzing 14 edible oils. All six compounds were present in at least some of the edible oils. The most abundant phytosterol in all samples was ß-sitosterol, which was highest in corn oil at 4.35 ± 0.03 mg/g, followed by campesterol in canola oil at 1.84 ± 0.01 mg/g. The new LC-MS-MS method for the quantitative analysis of phytosterols provides a combination of speed, selectivity and sensitivity that exceed those of previous assays.


Subject(s)
Chromatography, Liquid/methods , Phytosterols/analysis , Plant Oils/chemistry , Tandem Mass Spectrometry/methods , Cholestadienols/analysis , Cholestadienols/chemistry , Cholesterol/analogs & derivatives , Cholesterol/analysis , Cholesterol/chemistry , Molecular Structure , Pentacyclic Triterpenes/analysis , Pentacyclic Triterpenes/chemistry , Phytosterols/chemistry , Reproducibility of Results , Sitosterols/analysis , Sitosterols/chemistry , Stigmasterol/analysis , Stigmasterol/chemistry , Triterpenes/analysis , Triterpenes/chemistry
8.
Curr Drug Targets ; 12(11): 1654-73, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21561419

ABSTRACT

Cyanobacteria are considered a promising source for new pharmaceutical lead compounds and a large number of chemically diverse and bioactive metabolites have been obtained from cyanobacteria over the last few decades. This review highlights the structural diversity of natural products from freshwater and terrestrial cyanobacteria. The review is divided into three areas: cytotoxic metabolites, protease inhibitors, and antimicrobial metabolites. The first section discusses the potent cytotoxins cryptophycin and tolytoxin. The second section covers protease inhibitors from freshwater and terrestrial cyanobacteria and is divided in five subsections according to structural class: aeruginosins, cyanopeptolins, microviridins, anabaenopeptins, and microginins. Structure activity relationships are discussed within each protease inhibitor class. The third section, antimicrobial metabolites from freshwater and terrestrial cyanobacteria, is divided by chemical class in three subsections: alkaloids, peptides and terpenoids. These examples emphasize the structural diversity and drug development potential of natural products from freshwater and terrestrial cyanobacteria.


Subject(s)
Biodiversity , Cyanobacteria/classification , Fresh Water/microbiology
9.
J Chem Inf Model ; 51(1): 171-80, 2011 Jan 24.
Article in English | MEDLINE | ID: mdl-21162567

ABSTRACT

A software package, termed "CYANOS", has been developed to facilitate the data management and mining for natural product drug discovery efforts. This system allows for the management of data associated with field collections, culture conditions, harvests, extractions, chemical separations, and biological evaluation. This software utilizes a MySQL database for data storage, which allows for reporting and data mining via third party tools. In addition, a Web-based interface was constructed to allow for multiuser access from a variety of desktop platforms. The code for this system is freely available and has been released under the Illinois Open Source license.


Subject(s)
Biological Products , Culture Techniques , Cyanobacteria/growth & development , Drug Discovery/methods , Information Management/methods , Software , Cell Line , Data Mining , Humans , Internet
10.
J Nat Prod ; 73(11): 1927-32, 2010 Nov 29.
Article in English | MEDLINE | ID: mdl-21058727

ABSTRACT

Two cyclic peptides, scytonemides A (1) and B (2), were isolated from the cultured fresh water cyanobacterium Scytonema hofmannii (UTEX 1834) by bioassay-guided fractionation using a proteasome inhibition assay. The planar structures of the compounds were determined by a combination of MS and 1D and 2D NMR spectroscopy. The advanced Marfey's method was used to determine the absolute configuration of both peptides. Scytonemide A possesses an unusual imino linkage, while scytonemide B is a depsipeptide containing 3-hydroxyoctanoic acid in the macrocycle. Both isolates were evaluated for their inhibition of the 20S proteasome, and scytonemide A displayed an IC(50) value of 96 nM, while scytonemide B was inactive at 50 µM.


Subject(s)
Antineoplastic Agents/pharmacology , Cyanobacteria/chemistry , Depsipeptides/isolation & purification , Depsipeptides/pharmacology , Proteasome Inhibitors , Antineoplastic Agents/chemistry , Antineoplastic Agents/isolation & purification , Caprylates/chemistry , Depsipeptides/chemistry , Drug Screening Assays, Antitumor , HT29 Cells , Humans , Inhibitory Concentration 50 , Molecular Structure , Nuclear Magnetic Resonance, Biomolecular
11.
Phytochemistry ; 71(17-18): 2116-23, 2010 Dec.
Article in English | MEDLINE | ID: mdl-20965528

ABSTRACT

Four hapalindole-related alkaloids, namely fischambiguines A and B, ambiguine P, ambiguine Q nitrile as well as ambiguine G nitrile were identified from the cultured cyanobacterium Fischerella ambigua (UTEX 1903). The structures were determined by spectroscopic analysis including MS, 1D and 2D NMR and X-ray crystallography. The alkaloids possessed fused pentacyclic and hexacyclic carbon skeletons. Fischambiguine B displayed a strong inhibitory activity against Mycobacterium tuberculosis with an MIC value of 2 µM, with no detectable cytotoxicity in a Vero cell line.


Subject(s)
Cyanobacteria/chemistry , Indole Alkaloids/chemistry , Indole Alkaloids/isolation & purification , Animals , Bacillus anthracis/drug effects , Candida albicans/drug effects , Chlorocebus aethiops , Crystallography, X-Ray , Indole Alkaloids/pharmacology , Microbial Sensitivity Tests , Molecular Conformation , Molecular Structure , Mycobacterium tuberculosis/drug effects , Nuclear Magnetic Resonance, Biomolecular , Staphylococcus aureus/drug effects , Vero Cells
12.
J Med Chem ; 53(13): 5033-43, 2010 Jul 08.
Article in English | MEDLINE | ID: mdl-20527891

ABSTRACT

Five resveratrol sulfate metabolites were synthesized and assessed for activities known to be mediated by resveratrol: inhibition of tumor necrosis factor (TNF) alpha induced NFkappaB activity, cylcooxygenases (COX-1 and COX-2), aromatase, nitric oxide production in endotoxin-stimulated macrophages, proliferation of KB or MCF7 cells, induction of quinone reductase 1 (QR1), accumulation in the sub-G(1) phase of the cell cycle, and quenching of 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical. Two metabolites showed activity in these assays; the 3-sulfate exhibited QR1 induction, DPPH free radical scavenging, and COX-1 and COX-2 inhibitory activities and the 4'-sulfate inhibited NFkappaB induction, as well as COX-1 and COX-2 activities. Resveratrol and its 3'-sulfate and 4-sulfate inhibit NO production by NO scavenging and down-regulation of iNOS expression in RAW 264.7 cells. Resveratrol sulfates displayed low antiproliferative activity and negligible uptake in MCF7 cells.


Subject(s)
Stilbenes/chemistry , Stilbenes/pharmacology , Sulfuric Acid Esters/chemistry , Sulfuric Acid Esters/pharmacology , Animals , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Aromatase/metabolism , Biphenyl Compounds/antagonists & inhibitors , Biphenyl Compounds/metabolism , Cell Survival/drug effects , Cyclooxygenase 1/metabolism , Cyclooxygenase 2/metabolism , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacology , HL-60 Cells , Humans , Inhibitory Concentration 50 , Macrophages/drug effects , Macrophages/metabolism , Magnetic Resonance Spectroscopy , Mice , NAD(P)H Dehydrogenase (Quinone)/antagonists & inhibitors , NAD(P)H Dehydrogenase (Quinone)/metabolism , NF-kappa B/antagonists & inhibitors , NF-kappa B/metabolism , Nitric Oxide Synthase/antagonists & inhibitors , Nitric Oxide Synthase/metabolism , Picrates/antagonists & inhibitors , Picrates/metabolism , Resveratrol , Spectrometry, Mass, Electrospray Ionization , Spectroscopy, Fourier Transform Infrared , Stilbenes/metabolism , Sulfuric Acid Esters/chemical synthesis
13.
J Nat Prod ; 72(11): 2043-5, 2009 Nov.
Article in English | MEDLINE | ID: mdl-19888742

ABSTRACT

Scytoscalarol (1), a antimicrobial sesterterpene bearing a guanidino group, was isolated from the cultured cyanobacterium Scytonema sp. (UTEX 1163) by bioassay-guided fractionation. The chemical structure was determined by spectroscopic analysis including MS and 1D and 2D NMR. Scytoscalarol (1) showed antimicrobial activities against Bacillus anthracis, Staphylococcus aureus, Escherichia coli, Candida albicans, and Mycobacterium tuberculosis with MIC values in the range from 2 to 110 microM.


Subject(s)
Anti-Bacterial Agents/isolation & purification , Anti-Bacterial Agents/pharmacology , Antifungal Agents/isolation & purification , Antifungal Agents/pharmacology , Cyanobacteria/chemistry , Guanidines/isolation & purification , Guanidines/pharmacology , Sesterterpenes/isolation & purification , Sesterterpenes/pharmacology , Anti-Bacterial Agents/chemistry , Antifungal Agents/chemistry , Bacillus anthracis/drug effects , Candida albicans/drug effects , Escherichia coli/drug effects , Guanidines/chemistry , Microbial Sensitivity Tests , Molecular Structure , Mycobacterium tuberculosis/drug effects , Nuclear Magnetic Resonance, Biomolecular , Sesterterpenes/chemistry , Staphylococcus aureus/drug effects
14.
Bioorg Med Chem ; 17(20): 7126-30, 2009 Oct 15.
Article in English | MEDLINE | ID: mdl-19783449

ABSTRACT

Indolo[2,3-a]carbazole based inhibitors were synthesized from readily available indigo via a seven-step linear synthetic sequence with a moderate overall yield. The inhibitors were selectively and readily functionalized at the nitrogen on the indole portion of the carbazole unit. The synthesized analogs displayed moderate inhibitory activities toward Bacillus anthracis and Mycobacterium tuberculosis, indicating that indolo[2,3-a]carbazoles could serve as promising leads in the development of new drugs to combat anthrax and tuberculosis infections.


Subject(s)
Anti-Bacterial Agents/isolation & purification , Biological Products/pharmacology , Carbazoles/isolation & purification , Drug Discovery , Anti-Bacterial Agents/chemical synthesis , Anti-Bacterial Agents/pharmacology , Bacillus anthracis/drug effects , Carbazoles/chemical synthesis , Carbazoles/pharmacology , Drug Evaluation, Preclinical , Ligands , Microbial Sensitivity Tests , Mycobacterium tuberculosis/drug effects
15.
J Nat Prod ; 72(5): 894-9, 2009 May 22.
Article in English | MEDLINE | ID: mdl-19371071

ABSTRACT

Five new antibacterial ambiguine K-O isonitriles (1-5) and eight previously described indole alkaloids were isolated from the cultured cyanobacterium Fischerella ambigua (UTEX 1903) by bioassay-guided fractionation. The planar structures of the new compounds were determined by spectroscopic analysis including MS and 1D and 2D NMR. X-ray crystallography was used to determine the absolute stereoconfiguration of ambiguine K isonitrile. The isolates were evaluated for their antibacterial activities against a set of bacterial targets, including Mycobacterium tuberculosis and Bacillus anthracis. Ambiguine K and M isonitriles showed the most potent activity against M. tuberculosis, with MIC values of 6.6 and 7.5 microM, respectively. Ambiguine A isonitrile showed the most potent activity against B. anthracis, with a MIC of 1.0 microM.


Subject(s)
Anti-Bacterial Agents/isolation & purification , Anti-Bacterial Agents/pharmacology , Cyanobacteria/chemistry , Indole Alkaloids/isolation & purification , Indole Alkaloids/pharmacology , Anti-Bacterial Agents/chemistry , Bacillus anthracis/drug effects , Indole Alkaloids/chemistry , Microbial Sensitivity Tests , Molecular Structure , Mycobacterium tuberculosis/drug effects , Nuclear Magnetic Resonance, Biomolecular
16.
Pharm Biol ; 47(1): 53-60, 2009 Jan.
Article in English | MEDLINE | ID: mdl-21430788

ABSTRACT

A culture collection of cyanobacteria has been established at the University of Illinois at Chicago. This collection includes marine, terrestrial, and freshwater strains and contains representatives of the five orders of cyanobacteria: Chroococcales, Pleurocapsales, Oscillatoriales, Nostocales, and Stigonematales. In this study, extracts from a subset of 61 strains, 16 marine and 45 freshwater/terrestrial, were evaluated against three current protease targets, i.e. 20S proteasome and two SARS viral proteases, two important bacterial targets, i.e. Mycobacterium tuberculosis and Bacillus anthracis, and in the Artemia salina toxicity assay. In total, extracts of 12 strains possessed significant levels of activity in one or more targets. The overwhelming majority of active extracts (11 of 12) were from either freshwater or terrestrial forms of cyanobacteria, with the greater part of these (9 of 12) being heterocyst-forming strains. These results further support the use of cultured cyanobacteria as a source of biologically active natural products.

17.
J Nat Prod ; 70(2): 296-9, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17279797

ABSTRACT

Further chemical investigation of the Chinese medicinal fungus Phellinus igniarius has resulted in the isolation and structural elucidation of three pyrano[4,3-c]isochromen-4-one derivatives, phelligridins H (1), I (2), and J (3), together with the known compounds davallialactone (4), scopolin, nebularine, uridine, trehalose, glucitol, and ethyl glucoside. The structures of 1-3 were elucidated by spectroscopic methods. Phelligridins H (1) and I (2) possess unprecedented carbon skeletons, and phelligridin J (3) is an oxidative derivative of the co-occurring phelligridin A. Compounds 1 and 2 inhibited protein tyrosine phosphatase 1B (PTP1B) and rat liver microsomal lipid peroxidation, while compound 3 exhibited cytotoxic activity against several human cancer cell lines.


Subject(s)
Antineoplastic Agents , Benzopyrans , Polyporaceae/chemistry , Animals , Antineoplastic Agents/chemistry , Antineoplastic Agents/isolation & purification , Antineoplastic Agents/pharmacology , Benzopyrans/chemistry , Benzopyrans/isolation & purification , Benzopyrans/pharmacology , China , Drug Screening Assays, Antitumor , Humans , Lipid Peroxidation/drug effects , Liver/drug effects , Molecular Structure , Protein Tyrosine Phosphatases/antagonists & inhibitors , Rats
18.
Org Lett ; 7(21): 4733-6, 2005 Oct 13.
Article in English | MEDLINE | ID: mdl-16209522

ABSTRACT

[structure: see text] A highly oxygenated and unsaturated 26-membered macrocyclic metabolite, phelligridimer A (1), has been isolated from the Chinese medicinal fungus Phellinus igniarius. Its structure was elucidated by spectroscopic methods. A possible biogenesis of 1 mediated by the fungal metabolite hispidin was postulated. Phelligridimer A showed antioxidant activity (IC50 of 10.2 microM) but was inactive to several human cancer cell lines (IC50 > 50 microM) and enzymes PTP1B (IC50 > 25 microM) and thrombin (IC50 > 10 microM).


Subject(s)
Antioxidants/isolation & purification , Basidiomycota/metabolism , Lipid Peroxidation/drug effects , Macrocyclic Compounds/isolation & purification , Pyrones/isolation & purification , Animals , Antioxidants/pharmacology , Cell Line, Tumor , Cell Survival/drug effects , Humans , Macrocyclic Compounds/pharmacology , Medicine, Chinese Traditional , Models, Molecular , Molecular Structure , Protein Tyrosine Phosphatases/antagonists & inhibitors , Pyrones/pharmacology , Rats
19.
Org Lett ; 7(9): 1675-8, 2005 Apr 28.
Article in English | MEDLINE | ID: mdl-15844878

ABSTRACT

[structure: see text] A unique pyrano[4,3-c][2]benzopyran-1,6-dione derivative with an unprecedented carbon skeleton, phelligridin G (1), has been isolated from the fruiting body of the fungus Phellinus igniarius. Its structure was elucidated by detailed spectroscopic analysis. A possible biogenetic origin of 1 mediated by the fungal metabolite precursor 4-hydroxy-6-methyl-2-pyrone was postulated. Phelligridin G (1) showed antioxidant activity inhibiting rat liver microsomal lipid peroxidation and moderate selective cytotoxic activities against human cancer cell lines.


Subject(s)
Antineoplastic Agents/isolation & purification , Antioxidants/isolation & purification , Benzopyrans/isolation & purification , Polyporaceae/chemistry , Animals , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Antioxidants/chemistry , Antioxidants/pharmacology , Benzopyrans/chemistry , Benzopyrans/pharmacology , Drug Screening Assays, Antitumor , Humans , Inhibitory Concentration 50 , Lipid Peroxidation/drug effects , Liver/drug effects , Liver/metabolism , Molecular Structure , Nuclear Magnetic Resonance, Biomolecular , Rats
20.
J Nat Prod ; 67(5): 823-8, 2004 May.
Article in English | MEDLINE | ID: mdl-15165144

ABSTRACT

Three unique pyrano[4,3-c][2]benzopyran-1,6-dione derivatives and a new furo[3,2-c]pyran-4-one, named phelligridins C-F (2-5), together with hispolon (8), (E)-4-(3,4-dihydroxyphenyl)but-3-en-2-one (9), 4-hydroxybenzaldehyde, protocatechualdehyde, syringic acid, protocatechuic acid, caffeic acid, isoergosterone, and octadecyl ferulate were isolated and identified from the ethanolic extract of Phellinus igniarius. Their structures were determined by spectroscopic methods including IR, MS, and 1D and 2D NMR experiments. The structures of the new compounds were characterized as 3-(4-hydroxystyryl)-8,9-dihydroxypyrano[4,3-c]isochromene-4-one (2), 3-(3,4-hydroxystyryl)-8,9-dihydroxypyrano[4,3-c]isochromene-4-one (3), 8,9-dihydroxy-3-[5',6'-dihydroxy-5' '-methyl-3' '-oxo-spiro[fural-2' '(3' 'H),1'-indene]-2'-yl]-1H,6H-pyrano[4,3-c][2]benzopyran-1,6-dione (4), and (3Z)-3-(3,4-dihydroxybenzylidene)-6-(3,4-dihydroxystyryl)-2,3-dihydro-2-methoxy-2-(2-oxo-propyl)furo[3,2-c]pyran-4-one (5), respectively. Some compounds including 2 and 3 showed in vitro selective cytotoxicity against a human lung cancer cell line (A549) and a liver cancer cell line (Bel7402). Possible biogenetic sequences to the formation of 1-9 are postulated.


Subject(s)
Antineoplastic Agents/isolation & purification , Benzofurans/isolation & purification , Benzopyrans/isolation & purification , Polyporaceae/chemistry , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Benzofurans/chemistry , Benzofurans/pharmacology , Benzopyrans/chemistry , Benzopyrans/pharmacology , China , Drug Screening Assays, Antitumor , Humans , Molecular Conformation , Molecular Structure , Stereoisomerism , Tumor Cells, Cultured
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