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Vito Alessandro Taddeo, Salvatore Genovese, Philippe de Medina, Roberta Palmisano, Francesco Epifano, Serena Fiorito
An analytical strategy based on different extraction methodologies and HPLC with spectrophotometric (UV-vis) detection has been developed to investigate the presence of and to quantitate biologically active selected unprenylated and O-prenylated phenylpropanoids, namely umbelliferone, 4'-geranyloxyferulic acid, 7-isopentenyloxycoumarin, auraptene, and umbelliprenin in dill (Anethum graveolens L.), anise (Pimpinella anisum L.), and wild celery (Angelica archangelica L.). Absolute ethanol or 7:3 water/ethanol mixtures were seen to be the most powerful extraction solvents to perform "classic" maceration or ultrasound-assisted one in terms of yields in secondary metabolites...
November 27, 2016: Journal of Pharmaceutical and Biomedical Analysis
Caroline Rouger, Sylvain Pagie, Séverine Derbré, Anne-Marie Le Ray, Pascal Richomme, Béatrice Charreau
Endothelial cells (ECs) are key players in inflammation and immune responses involved in numerous pathologies. Although attempts were experimentally undertaken to prevent and control EC activation, drug leads and probes still remain necessary. Natural products (NPs) from Clusiaceous and Calophyllaceous plants were previously reported as potential candidates to prevent endothelial dysfunction. The present study aimed to identify more precisely the molecular scaffolds that could limit EC activation. Here, 13 polyphenols belonging to 5 different chemical types of secondary metabolites (i...
2016: PloS One
Tatiana Yurchenko, Tereza Ševčíková, Hynek Strnad, Anzhelika Butenko, Marek Eliáš
Acquisition of genes by plastid genomes (plastomes) via horizontal gene transfer (HGT) seems to be a rare phenomenon. Here, we report an interesting case of HGT revealed by sequencing the plastomes of the eustigmatophyte algae Monodopsis sp. MarTras21 and Vischeria sp. CAUP Q 202. These plastomes proved to harbour a unique cluster of six genes, most probably acquired from a bacterium of the phylum Bacteroidetes, with homologues in various bacteria, typically organized in a conserved uncharacterized putative operon...
November 2016: Open Biology
Jana Braesel, Janis Fricke, Daniel Schwenk, Dirk Hoffmeister
The prenylphenols are a class of natural products that have been frequently isolated from basidiomycetes, e.g., from the genus Stereum (false turkey tail fungi) and other Russulales as well as from ascomycetes. Biosynthetically, these compounds are considered hybrids, as the orsellinic acid moiety is a polyketide and the prenyl side chain originates from the terpene metabolism, although no literature on the genetic and biochemical background of the biosynthesis is available. In a stereaceous basidiomycete, referred to as BY1, a new prenylphenol, now termed cloquetin, was identified and its structure elucidated by mass spectrometry and nuclear magnetic resonance spectroscopy...
November 27, 2016: Fungal Genetics and Biology: FG & B
Yang Hee Jo, Seon Beom Kim, Qing Liu, Bang Yeon Hwang, Mi Kyeong Lee
Investigation of the CH2 Cl2 and EtOAc-soluble fractions of the roots of Cudrania tricuspidata afforded 31 compounds. The structures of the isolated compounds were determined on the basis of spectroscopic data interpretation such as 1D and 2D NMR analysis and elucidated as xanthones with prenyl moieties including four simple xanthones (1-4), five prenylated xanthones with one prenyl moiety (5-7, 20, and 21), and 22 prenylated xanthones with two prenyl moieties (8-19 and 22-31). Among them, three diprenylated xanthones named cudracuspixanthones E-G (16, 29, and 31) were first isolated in nature...
November 30, 2016: Archiv der Pharmazie
Tamás M Garay
The high mortality of solid tumors can be attributed to their invasive and metastatic potential that is based on their migration and proliferation. Importantly, growth factor receptor (GF) signaling pathways regulating proliferation and migration are often affected by oncogenic mutations and are important targets for antitumor therapy. We found positive correlation between migration and proliferation in melanoma and lung cancer cells using videomicroscopy, not supporting the "go or grow" hypothesis. Furthermore, the invasion into collagen I matrices from brain tumor spheroids was not impaired upon the inhibition of proliferation...
November 29, 2016: Magyar Onkologia
Colin C Duke, Van H Tran, Rujee K Duke, Abdallah Abu-Mellal, George T Plunkett, Douglas I King, Kaiser Hamid, Karen L Wilson, Russell L Barrett, Jeremy J Bruhl
Propolis samples from Kangaroo Island, South Australia, were investigated for chemical constituents using high-field nuclear magnetic resonance spectral profiling. A type of propolis was found containing a high proportion of prenylated hydroxystilbenes. Subsequently, the botanical origin of this type of propolis was identified using a beehive propolis depletion method and analysis of flora. Ligurian honey bees, Apis mellifera ligustica Spinola, were found to produce propolis from resin exuded by the Australian native sedge plant Lepidosperma sp...
November 24, 2016: Phytochemistry
Jouko Sandholm, Jaakko Lehtimäki, Tamiko Ishizu, Sadanandan E Velu, Jeremy Clark, Pirkko Härkönen, Arja Jukkola-Vuorinen, Aleksi Schrey, Kevin W Harris, Johanna M Tuomela, Katri S Selander
Bisphosphonates are standard treatments for bone metastases. When given in the adjuvant setting, they reduce breast cancer mortality and recurrence in bone but only among post-menopausal patients. Optimal drug use would require biomarker-based patient selection. Such biomarkers are not yet in clinical use. Based on the similarities in inflammatory responses to bisphosphonates and Toll-like receptor (TLR) agonists, we hypothesized that TLR9 expression may affect bisphosphonate responses in cells. We compared bisphosphonate effects in breast cancer cell lines with low or high TLR9 expression...
November 24, 2016: Oncotarget
Dijovani Batista Dos Reis, Thalita Cristina Alves Souza, Maria Cristina S Lourenço, Mauro Vieira de Almeida, Adriano Barbosa, Iriane Eger, Mauricio Frota Saraiva
We report the synthesis of a series of diaminated terpenoids containing, as side-chain of the diamine core, the "head-to-tail" prenyl derivatives, with amino amino spacers of variable length. In vitro biological activity of these compounds was evaluated against Mycobacterium tuberculosis and Leishmania amazonensis, and the structure-activity relationships are discussed. Different biological results were observed depending on the terpenic side-chain length. The best results were obtained for trans,trans-farnesol derivatives...
November 18, 2016: Biomedicine & Pharmacotherapy, Biomédecine & Pharmacothérapie
Yue Hao, Elizabeth Pierce, Daniel Roe, Maho Morita, John A McIntosh, Vinayak Agarwal, Thomas E Cheatham, Eric W Schmidt, Satish K Nair
The cyanobactin prenyltransferases catalyze a series of known or unprecedented reactions on millions of different substrates, with no easily observable recognition motif and exquisite regioselectivity. Here we define the basis of broad substrate tolerance for the otherwise uncharacterized TruF family. We determined the structures of the Tyr-prenylating enzyme PagF, in complex with an isoprenoid donor analog and a panel of linear and macrocyclic peptide substrates. Unexpectedly, the structures reveal a truncated barrel fold, wherein binding of large peptide substrates is necessary to complete a solvent-exposed hydrophobic pocket to form the catalytically competent active site...
November 21, 2016: Proceedings of the National Academy of Sciences of the United States of America
Zuodong Jiang, Chase Kempinski, Joe Chappell
Terpenes/terpenoids constitute one of the largest classes of natural products, this is due to the incredible chemical diversity that can arise from the biochemical transformations of the relatively simple prenyl diphosphate starter units. All terpenes/terpenoids comprise a hydrocarbon backbone that is generated from the various length prenyl diphosphates (a polymer chain of prenyl units). Upon ionization (removal) of the diphosphate group, the remaining allylic carbocation intermediates can be coaxed down complex chemical cascades leading to diverse linear and cyclized hydrocarbon backbones, which can then be further modified with a wide range of functional groups (e...
2016: Current Protocols in Plant Biology
A H Oliveira, G G de Oliveira, F Carnevale Neto, D F Portuondo, A Batista-Duharte, I Z Carlos
ETHNOPHARMACOLOGICAL RELEVANCE: Vismia guianensis (Aubl.) Pers. is traditionally used in North and Northeast of Brazil for the treatment of dermatomycoses. Since the strategy associating immunomodulators with antifungal drugs seems to be promissory to improve the treatment efficacy in fungal infections, we aimed to investigate the antifungal activity of V. guianensis ethanolic extract of leaves (VGL) and bark (VGB) against Sporothrix schenckii ATCC 16345 and their antinflammatory activities...
November 14, 2016: Journal of Ethnopharmacology
Wei Zhao, Aili Fan, Sylwia Tarcz, Kang Zhou, Wen-Bing Yin, Xiao-Qing Liu, Shu-Ming Li
The fungal cyclic dipeptide prenyltransferase FtmPT1 from Aspergillus fumigatus catalyzes a regular C2-prenylation of brevianamide F (cyclo-L-Trp-L-Pro) and is involved in the biosynthesis of a number of biologically active natural products including tryprostatins, spirotryprostatins, verruculogen, and fumitremorgins. FtmPT1, like other members of the dimethylallyltryptophan synthase superfamily, was shown to have high substrate promiscuity for tryptophan-containing cyclic dipeptides and a few other aromatic substrates...
November 10, 2016: Applied Microbiology and Biotechnology
Suyu Gao, Dejuan Sun, Guan Wang, Jin Zhang, Yingnan Jiang, Guoyu Li, Ke Zhang, Lei Wang, Jian Huang, Lixia Chen
Five flavones, including four flavonoids and one prenylated chalcone (paratocarpin E), were isolated from E. humifusa. and their chemical structures were established by spectroscopic analyses. We assessed the efficacy of these compounds against the growth of human breast cancer, leukemic, kidney cancer cell lines. Among them, paratocarpin E showed significant cytotoxicity against these cancer cell lines with an IC50 of 19.6μM on the growth of MCF-7 cells. Paratocarpin E treatment of MCF-7 cells resulted in typical apoptotic features via increasing expression of activated caspase-8 and -9 and PARP cleavage...
October 25, 2016: Bioorganic Chemistry
Sandip Murarka, Pablo Martín-Gago, Carsten Schultz-Fademrecht, Alaa Al Saabi, Matthias Baumann, Eyad Fansa, Shehab Ismail, Peter Nussbaumer, Alfred Wittinghofer, Herbert Waldmann
The K-Ras GTPase is a major target in anticancer drug discovery. However, direct interference with signaling by K-Ras has not led to clinically useful drugs yet. Correct localization and signaling by farnesylated K-Ras is regulated by the prenyl binding protein PDEδ. Interfering with binding of PDEδ to K-Ras by means of small molecules provides a novel opportunity to suppress oncogenic signaling. Here we describe the identification and structure-guided development of novel K-Ras-PDEδ inhibitor chemotypes based on pyrrolopyridazinones and pyrazolopyridazinones that bind to the farnesyl binding pocket of PDEδ with low nanomolar affinity...
November 3, 2016: Chemistry: a European Journal
Tynchtyk Amatov, Martin Gebauer, Radek Pohl, Ivana Cisařová, Ullrich Jahn
A novel approach to the diazabicyclo[2.2.2]octane core of prenylated bridged diketopiperazine alkaloids is described by direct oxidative cyclizations of functionalized diketopiperazines mediated by ferrocenium hexafluorophosphate or the Mn(OAc)3•2H2O/Cu(OTf)2 system. Divergent reaction pathways take place depending on the substitution pattern of the substrates and the oxidation conditions such as temperature or the presence or absence of persistent radical TEMPO. For ester-substituted diketopiperazines, the ester group exerts a significant influence on the reaction outcome and stereochemistry of the radical cyclizations...
November 2, 2016: Free Radical Research
Gibson Gomes de Oliveira, Fausto Carnevale Neto, Daniel Pecoraro Demarque, José Antônio de Sousa Pereira-Junior, Rômulo César Sampaio Peixoto Filho, Sebastião José de Melo, Jackson Roberto Guedes da Silva Almeida, João Luiz Callegari Lopes, Norberto Peporine Lopes
The interpretation of large datasets acquired using high performance liquid chromatography coupled with tandem mass spectrometry represents one of the major challenges in natural products research. Here we propose the use of molecular networking to rapid identify the known secondary metabolites from untargeted MS/MS analysis of Adenocalymma imperatoris-maximilianii plant extracts. The leaves, stems and roots of A. imperatoris-maximilianii were extracted using different solvents according to Snyder selectivity triangle...
November 2, 2016: Planta Medica
Masanobu Tsubaki, Daichiro Fujiwara, Tomoya Takeda, Toshiki Kino, Yoshika Tomonari, Tatsuki Itoh, Motohiro Imano, Takao Satou, Katsuhiko Sakaguchi, Shozo Nishida
Statins induce apoptosis of tumor cells by inhibiting the prenylation of small G-proteins. However, the details of the apoptosis-inducing mechanisms remain poorly understood. The present study showed that the induction of apoptosis by statins in four different human head and neck squamous cell carcinoma (HNSCC) cell lines, HSC-3, HEp-2, Ca9-22, and SAS cells was mediated by increased caspase-3 activity. Statins induced apoptosis by the suppression of geranylgeranyl pyrophosphate biosynthesis. Furthermore, statins decreased the levels of phosphorylated ERK and mTOR by inhibiting the membrane localization of Ras and enhancing Bim expression in HSC-3 and HEp-2 cells...
November 2, 2016: Clinical and Experimental Pharmacology & Physiology
Rajakrishnan Veluthakal, Daleep K Arora, Marc L Goalstone, Renu A Kowluru, Anjaneyulu Kowluru
BACKGROUND/AIMS: At least 300 prenylated proteins are identified in the human genome; the majority of which partake in a variety of cellular processes including growth, differentiation, cytoskeletal organization/dynamics and vesicle trafficking. Aberrant prenylation of proteins is implicated in human pathologies including cancer; neurodegenerative diseases, retinitis pigmentosa, and premature ageing syndromes. Original observations from our laboratory have demonstrated that prenylation of proteins [small G-proteins and γ-subunits of trimeric G-proteins] is requisite for physiological insulin secretion...
2016: Cellular Physiology and Biochemistry
Anika Wranke, Heiner Wedemeyer
Hepatitis B-/D-virus co-infection causes the most severe form of viral hepatitis, frequently leading to liver cirrhosis, hepatic decompensation and consecutive liver-related mortality. Treatment options for hepatitis delta are limited. The only recommended therapy is pegylated interferon alpha which leads to virological responses in about 25-30% of patients. However, interferon therapy is associated with frequent side-effects and late HDV RNA relapses have been described during long-term follow even in patients who were HDV RNA negative 24 weeks after the end of therapy...
October 25, 2016: Current Opinion in Virology
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