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https://www.readbyqxmd.com/read/28102286/chelerythrine-down-regulates-expression-of-vegfa-bcl2-and-kras-by-arresting-g-quadruplex-structures-at-their-promoter-regions
#1
Jagannath Jana, Soma Mondal, Payel Bhattacharjee, Pallabi Sengupta, Tanaya Roychowdhury, Pranay Saha, Pallob Kundu, Subhrangsu Chatterjee
A putative anticancer plant alkaloid, Chelerythrine binds to G-quadruplexes at promoters of VEGFA, BCL2 and KRAS genes and down regulates their expression. The association of Chelerythrine to G-quadruplex at the promoters of these oncogenes were monitored using UV absorption spectroscopy, fluorescence anisotropy, circular dichroism spectroscopy, CD melting, isothermal titration calorimetry, molecular dynamics simulation and quantitative RT-PCR technique. The pronounced hypochromism accompanied by red shifts in UV absorption spectroscopy in conjunction with ethidium bromide displacement assay indicates end stacking mode of interaction of Chelerythrine with the corresponding G-quadruplex structures...
January 19, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28102026/piperine-a-pungent-alkaloid-from-black-pepper-inhibits-b-lymphocyte-activation-and-effector-functions
#2
David A Soutar, Carolyn D Doucette, Robert S Liwski, David W Hoskin
Piperine has several well-documented anti-inflammatory properties; however, little is known regarding its effect on humoral immunity. In this study, we describe the immunosuppressive effect of piperine on B lymphocytes, which are integral to the humoral immune response. Mouse B cells were cultured in the absence or presence of non-cytotoxic concentrations (25, 50, and 100 μM) of piperine during T-dependent or T-independent stimulation. Piperine inhibited B cell proliferation by causing G0/G1 phase cell cycle arrest in association with reduced expression of cyclin D2 and D3...
January 19, 2017: Phytotherapy Research: PTR
https://www.readbyqxmd.com/read/28101849/mechanistic-study-of-the-gas-phase-in-source-hofmann-elimination-of-doubly-quaternized-cinchona-alkaloid-based-phase-transfer-catalysts-by-electrospray-ionization-tandem-mass-spectrometry
#3
Rong-Sheng Yang, Huaming Sheng, Katrina W Lexa, Edward C Sherer, Li-Kang Zhang, Bangping Xiang, Roy Helmy, Bing Mao
An unusual in-source fragmentation pattern observed for 14 doubly quaternized cinchona alkaloid-based phase-transfer catalysts (PTC) was studied using (+)-ESI high resolution mass spectrometry. Loss of the substituted benzyl cation (R1 or R2) was found to be the major product ion [M(2+) - R1(+) or R2(+)](+) in MS spectra of all PTC compounds. A Hofmann elimination product ion [M - H](+) was also observed. Only a small amount of the doubly charged M(2+) ions were observed in the MS spectra, likely due to strong Columbic repulsion between the two quaternary ammonium cations in the gas phase...
January 18, 2017: Journal of the American Society for Mass Spectrometry
https://www.readbyqxmd.com/read/28101464/anti-inflammatory-and-antibothropic-properties-of-jatropha-elliptica-a-plant-from-brazilian-cerrado-biome
#4
Sára Cósta Ferreira-Rodrigues, Cássio Milhomens Rodrigues, Marcio Galdino Dos Santos, Jean Antonio Abraham Gautuz, Magali Glauzer Silva, José Carlos Cogo, Camila Batista-Silva, Cleiton Pita Dos Santos, Francisco Carlos Groppo, Karina Cogo-Müller, Yoko Oshima-Franco
Purpose: The aim of this study was to evaluate the antibothropic and anti-inflammatory properties of J. elliptica.Methods: Phytochemical screening and thin-layer chromatography (TLC) assays were performed on J. elliptica hydroalcoholic extract (TE) in order to observe its main constituents. The antibothropic activity of TE was evaluated by the in vitro neuromuscular blockade caused by Bothrops jararacussu venom (Bjssu), in a mouse phrenic nerve-diaphragm model (PND). A quantitative histological study was carried out to observe a possible protection of TE against the venom myotoxicity...
December 2016: Advanced Pharmaceutical Bulletin
https://www.readbyqxmd.com/read/28101325/role-of-psilocybin-in-the-treatment-of-depression
#5
Ananya Mahapatra, Rishi Gupta
Psilocybin is a naturally occurring alkaloid, pharmacologically similar to the classic hallucinogen lysergic acid diethylamide (LSD). Although primarily used as a recreational drug or an entheogen in particular cultural settings, recent population based studies have shown that it does not lead to serious physical or mental health problems or dependent use. In view of recent work demonstrating psilocybin's potential to increase subjective sense of wellbeing and because of its novel mechanism of 5-HT2A serotonin receptor agonism, it is being explored for possible therapeutic utility in mood and anxiety disorders...
January 2017: Therapeutic Advances in Psychopharmacology
https://www.readbyqxmd.com/read/28099401/vocal-cord-palsy-in-children-with-cancer-a-10-year-analysis-of-uk-pediatric-intensive-care-admissions
#6
Anna Capsomidis, Andrew Hall, Hamid Daya, Jonathan Round, Donna Lancaster, Jessica Bate
Vocal cord palsy (VCP) is a rare but potentially life-threatening complication in children with cancer. This study reviews UK Intensive Care admissions for children with cancer and VCP using data obtained from the Pediatric Intensive Care Audit Network (PICANet) database. 26 children with cancer and VCP were admitted to intensive care from 2002 to 2012. The majority of admissions (23/26) required respiratory intervention (17 invasive ventilation, 8 noninvasive ventilation, and 5 tracheostomy). VCP should be considered early in children with cancer who present with signs of upper airway obstruction, especially in those receiving vinca-alkaloids as VCP is likely to be reversible...
January 17, 2017: Journal of Pediatric Hematology/oncology
https://www.readbyqxmd.com/read/28099003/-neocaryachine-an-antiproliferative-pavine-alkaloid-from-cryptocarya-laevigata-induces-dna-double-strand-breaks
#7
Yuki Suzuki, Yohei Saito, Masuo Goto, David J Newman, Barry R O'Keefe, Kuo-Hsiung Lee, Kyoko Nakagawa-Goto
Twelve benzylisoquinoline alkaloids, including pavine and phenanthroindolizidine types, were isolated from a MeOH/CH2Cl2 extract of Cryptocarya laevigata (stem bark) through bioactivity-guided fractionation for antitumor effects. Selected compounds were evaluated for antiproliferative activity against five human tumor cell lines, including a multidrug-resistant subline. Since more common 2,3,8,9-tetrasubstituted pavine alkaloids, such as crychine (3), exhibit very mild or no cytotoxicity, this compound type has not been well investigated for antitumor activity...
January 18, 2017: Journal of Natural Products
https://www.readbyqxmd.com/read/28098779/unravelling-the-diversity-of-the-cyclopiazonic-acid-family-of-mycotoxins-in-aspergillus-flavus-by-uhplc-triple-tof-hrms
#8
Valdet Uka, Geromy G Moore, Natalia Arroyo-Manzanares, Dashnor Nebija, Sarah De Saeger, José Diana Di Mavungu
Cyclopiazonic acid (α-cyclopiazonic acid, α-CPA) is an indole-hydrindane-tetramic acid neurotoxin produced by various fungal species, including the notorious food and feed contaminant Aspergillus flavus. Despite its discovery in A. flavus cultures approximately 40 years ago, its contribution to the A. flavus mycotoxin burden is consistently minimized by our focus on the more potent carcinogenic aflatoxins also produced by this fungus. Here, we report the screening and identification of several CPA-type alkaloids not previously found in A...
January 13, 2017: Toxins
https://www.readbyqxmd.com/read/28097799/stereocontrolled-total-synthesis-of-stemaphylline
#9
Ana Varela, Lennart K B Garve, Daniele Leonori, Varinder K Aggarwal
Homologation of readily available α-boryl pyrrolidines with metal carbenoids is especially challenging even when good leaving groups (Cl(-) ) are employed. By performing a solvent switch from Et2 O to CHCl3 , efficient 1,2-metalate rearrangement of the intermediate boronate occurs with both halide and ester leaving groups. The methodology was used in the total synthesis of the Stemona alkaloid (-)-stemaphylline in just 11 steps (longest linear sequence), with high stereocontrol (>20:1 d.r.) and 11 % overall yield...
January 18, 2017: Angewandte Chemie
https://www.readbyqxmd.com/read/28097798/discovery-of-novel-cinchona-alkaloid-inspired-oxazatwistane-autophagy-inhibitors
#10
Luca Laraia, Kosuke Ohsawa, Georgios Konstantinidis, Lucas Robke, Yao-Wen Wu, Kamal Kumar, Herbert Waldmann
The cinchona alkaloids are a privileged class of natural products and are endowed with diverse bioactivities. However, for compounds with the closely-related oxazatricyclo[4.4.0.0]decane ("oxazatwistane") scaffold, which are accessible from cinchonidine and quinidine by means of ring distortion and modification, biological activity has not been identified. We report the synthesis of an oxazatwistane compound collection through employing state-of-the-art C-H functionalization, and metal-catalyzed cross-coupling reactions as key late diversity-generating steps...
January 18, 2017: Angewandte Chemie
https://www.readbyqxmd.com/read/28096658/anticancer-and-anti-inflammatory-activities-of-girinimbine-isolated-from-murraya-koenigii
#11
Venoos Iman, Syam Mohan, Siddig Ibrahim Abdelwahab, Hamed Karimian, Noraziah Nordin, Mehran Fadaeinasab, Mohamad Ibrahim Noordin, Suzita Mohd Noor
Therapy that directly targets apoptosis and/or inflammation could be highly effective for the treatment of cancer. Murraya koenigii is an edible herb that has been traditionally used for cancer treatment as well as inflammation. Here, we describe that girinimbine, a carbazole alkaloid isolated from M. koenigii, induced apoptosis and inhibited inflammation in vitro as well as in vivo. Induction of apoptosis in human colon cancer cells (HT-29) by girinimbine revealed decreased cell viability in HT-29, whereas there was no cytotoxic effect on normal colon cells...
2017: Drug Design, Development and Therapy
https://www.readbyqxmd.com/read/28095673/a-comparative-study-of-hepatotoxicity-of-pyrrolizidine-alkaloids-retrorsine-and-monocrotaline
#12
Xiaojing Yang, Weiwei Li, Ying Sun, Xiucai Guo, Wenlin Huang, Ying Peng, Jiang Zheng
Many pyrrolizidine alkaloids (PAs) can cause liver injury in animals and humans. Different hepatotoxic PAs can produce similar hepatotoxic effects, but the degree of their toxicities may vary widely. Retrorsine (RTS) and monocrotaline (MCT) share the same core structure (retronecine) and similar metabolic activation pathway. RTS and MCT both produced liver injury but the former was more hepatotoxic than the latter. Enzyme kinetic study demonstrated that the value of Vmax/Km for RTS was 5.5-fold larger than that of MCT...
January 17, 2017: Chemical Research in Toxicology
https://www.readbyqxmd.com/read/28094969/investigating-biogenetic-hypotheses-of-the-securinega-alkaloids-enantioselective-total-syntheses-of-secu-amamine-e-ent-virosine-a-and-bubbialine
#13
Robin Wehlauch, Simone M Grendelmeier, Hideki Miyatake-Ondozabal, Alexander H Sandtorv, Manuel Scherer, Karl Gademann
The synthesis of the Securinega alkaloid secu'amamine E (ent-virosine A) has been accomplished for the first time in 12 steps and 8.5% overall yield. In addition, bubbialine has been prepared and characterized. These two alkaloids and bubbialidine, all featuring an azabicyclo[2.2.2]octane core, were rearranged to their azabicyclo[3.2.1]octane congeners, a framework found in many Securinega alkaloids. These experiments suggest that azabicyclo[2.2.2]octane derivatives could serve as intermediates in the biosynthesis of the rearranged azabicyclo[3...
January 17, 2017: Organic Letters
https://www.readbyqxmd.com/read/28094274/folivory-elicits-a-strong-defense-reaction-in-catharanthus-roseus-metabolomic-and-transcriptomic-analyses-reveal-distinct-local-and-systemic-responses
#14
Thomas Dugé de Bernonville, Inês Carqueijeiro, Arnaud Lanoue, Florent Lafontaine, Paloma Sánchez Bel, Franziska Liesecke, Karine Musset, Audrey Oudin, Gaëlle Glévarec, Olivier Pichon, Sébastien Besseau, Marc Clastre, Benoit St-Pierre, Victor Flors, Stéphane Maury, Elisabeth Huguet, Sarah E O'Connor, Vincent Courdavault
Plants deploy distinct secondary metabolisms to cope with environment pressure and to face bio-aggressors notably through the production of biologically active alkaloids. This metabolism-type is particularly elaborated in Catharanthus roseus that synthesizes more than a hundred different monoterpene indole alkaloids (MIAs). While the characterization of their biosynthetic pathway now reaches completion, still little is known about the role of MIAs during biotic attacks. As a consequence, we developed a new plant/herbivore interaction system by challenging C...
January 17, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28094223/anti-tuberculosis-activity-and-structure-activity-relationships-of-oxygenated-tricyclic-carbazole-alkaloids-and-synthetic-derivatives
#15
Carsten Börger, Christian Brütting, Konstanze K Julich-Gruner, Ronny Hesse, V Pavan Kumar, Sebastian K Kutz, Marika Rönnefahrt, Claudia Thomas, Baojie Wan, Scott G Franzblau, Hans-Joachim Knölker
A series of 49 oxygenated tricyclic carbazole derivatives has been tested for inhibition of the growth of Mycobacterium tuberculosis and a mammalian cell line (vero cells). From this series, twelve carbazoles showed a significant anti-TB activity. The four most active compounds were the naturally occurring carbazole alkaloids clauszoline-M (45), murrayaline-C (41), carbalexin-C (27), and the synthetic carbazole derivative 22 with MIC90 values ranging from 1.5 to 3.7μM. The active compounds were virtually nontoxic for the mammalian cell line in the concentration range up to 50μM...
December 27, 2016: Bioorganic & Medicinal Chemistry
https://www.readbyqxmd.com/read/28093998/potential-of-plant-alkaloids-as-antipyretic-drugs-of-future
#16
Imad Ahmad, Haroon Khan, Anwar Ul-Hassan Gilani, Mohammad A Kamal
Fever or Pyrexia means abnormal rise in body temperature above the usual range of normal in response to a variety of infectious, immunological and neoplastic stimuli. To normalize these febrile conditions, several synthetic agents are in clinical practice such as acetaminophen, ibuprofen, and aspirin. However, they are having many side effects which sometimes challenge their applications. The various sources are under investigation worldwide to overcome issues of unwanted effects and to better therapeutic response...
January 15, 2017: Current Drug Metabolism
https://www.readbyqxmd.com/read/28093031/the-inhibitory-effects-of-five-alkaloids-on-the-substrate-transport-mediated-through-human-organic-anion-and-cation-transporters
#17
Tahiatul Shams, Xiaoxi Lu, Ling Zhu, Fanfan Zhou
1. Human Solute Carrier Transporters (SLCs) are important membrane proteins mediate the cellular transport of many endogenous and exogenous substances. Organic anion/cation transporters (OATs/OCTs) and Organic anion transporting polypeptides (OATPs) are essential SLCs involved in drug influx. Drug-drug/herb interactions through competing for specific SLCs often lead to unsatisfied therapeutic outcomes and/or unwanted side effects. In this study we comprehensively investigated the inhibitory effects of five clinically relevant alkaloids (dendrobine, matrine, oxymatrine, tryptanthrin and chelerythrine) on the substrate transport through several OATs/OCTs and OATPs...
January 17, 2017: Xenobiotica; the Fate of Foreign Compounds in Biological Systems
https://www.readbyqxmd.com/read/28092947/pyrrolizidine-alkaloids-metabolic-activation-pathways-leading-to-liver-tumor-initiation
#18
Peter P Fu
Pyrrolizidine alkaloids (PAs) and PA N-oxides are a class of phytochemical carcinogens contained in over 6000 plant species spread around the world. It has been estimated that approximately half of the 660 PAs and PA N-oxides that have been characterized are cytotoxic, genotoxic, and tumorigenic. It was recently determined that a genotoxic mechanism of liver tumor initiation mediated by PA-derived DNA adducts is a common metabolic activation pathway of a number of PAs. We proposed this set of PA-derived DNA adducts could be a common biological biomarker of PA exposure and a potential biomarker of PA-induced liver tumor formation...
January 17, 2017: Chemical Research in Toxicology
https://www.readbyqxmd.com/read/28090769/synthesis-of-1-thio-substituted-isoquinoline-derivatives-by-tandem-cyclization-of-isothiocyanates
#19
Li-Rong Wen, Qian Dou, Yuan-Chao Wang, Jinwei Zhang, Wei-Si Guo, Ming Li
A copper-catalyzed tandem arylation-cyclization process to access 1-(arylthio)isoquinolines from isothiocyanates and diaryliodonium salts is described. It is the first general method to construct the potentially useful 1-(arylthio)isoquinoline derivatives. Moreover, 1-(methylthio)isoquinolines were also achieved successfully with MeOTf instead of diaryliodonium salts under metal-free conditions. Mechanistic studies reveal that these two processes proceed in different routes. This method has been successfully applied to the synthesis of quinazolinone alkaloid rutaecarpine...
January 16, 2017: Journal of Organic Chemistry
https://www.readbyqxmd.com/read/28089847/the-binding-orientation-of-epibatidine-at-%C3%AE-7-nach-receptors
#20
Andrew J Thompson, Simon Metzger, Martin Lochner, Marc-David Ruepp
Epibatidine is an alkaloid toxin that binds with high affinity to nicotinic and muscarinic acetylcholine receptors, and has been extensively used as a research tool. To examine binding interactions at the nicotinic receptor, it has been co-crystallised with the structural homologue acetylcholine binding protein (AChBP; PDB ID 2BYQ), and with an AChBP chimaera (3SQ6) that shares 64% sequence identity with the α7 nACh receptor. However, the binding orientations revealed by AChBP co-crystal structures may not precisely represent their receptor homologues and experimental evidence is needed to verify the ligand poses...
January 12, 2017: Neuropharmacology
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