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L-methyl tryptophan

Sharon K Michelhaugh, Otto Muzik, Anthony R Guastella, Neil V Klinger, Lisa A Polin, Hancheng Cai, Yanchun Xin, Thomas J Mangner, Shaohui Zhang, Csaba Juhasz, Sandeep Mittal
: Abnormal tryptophan metabolism via the kynurenine pathway (KP) is involved in the pathophysiology of a variety of human diseases including cancers. α-[(11)C]-methyl-L-tryptophan ((11)C-AMT) positron emission tomography (PET) imaging demonstrated increased tryptophan uptake and trapping in epileptic foci and brain tumors, but the short half-life of (11)C limits its widespread clinical application. Recent in vitro studies suggested that the novel radiotracer 1-(2-[(18)F]fluoroethyl)-L-tryptophan ((18)F-FETrp) may be useful to assess tryptophan metabolism via the KP...
October 20, 2016: Journal of Nuclear Medicine: Official Publication, Society of Nuclear Medicine
Brenda Gomes Fanchiotti, Marcella Piffer Zamprogno Machado, Letícia Camilato de Paula, Mahmut Durmuş, Tebello Nyokong, Arlan da Silva Gonçalves, André Romero da Silva
The photobleaching of an unsubstituted phthalocyanine (gallium(III) phthalocyanine chloride (GaPc)) and a substituted phthalocyanine (1,4-(tetrakis[4-(benzyloxy)phenoxy]phthalocyaninato) indium(III) chloride (InTBPPc)) was monitored for the free photosensitizers and for the phthalocyanines encapsulated into nanoparticles of PEGylated poly(D,L-lactide-co-glycolide) (PLGA-PEG). Phosphate-buffered solutions (PBS) and organic solutions of the free GaPc or the free InTBPPc, and suspensions of each encapsulated photosensitizer (2-15μmol/L) were irradiated using a laser diode of 665nm with a power of 1-104mW and a light dose of 7...
October 11, 2016: Journal of Photochemistry and Photobiology. B, Biology
Maximiliano L Agazzi, M Belén Ballatore, Eugenia Reynoso, Ezequiel D Quiroga, Edgardo N Durantini
Two cationic BODIPYs 3 and 4 were synthesized by acid-catalyzed condensation of the corresponding pyrrole and benzaldehyde, followed by complexation with boron and methylation. Compound 3 contains methyl at the 1,3,5 and 7 positions of the s-indacene ring and a N,N,N-trimethylamino group attached to the phenylene unit, while 4 is not substituted by methyl groups and the cationic group is bound by an aliphatic spacer. UV-visible absorption spectra of these BODIPYs show an intense band at ∼500 nm in solvents of different polarities and n-heptane/sodium bis(2-ethylhexyl)sulfosuccinate (AOT)/water reverse micelles...
October 3, 2016: European Journal of Medicinal Chemistry
Julia Winkelblech, Xiulan Xie, Shu-Ming Li
Prenylated secondary metabolites including indole derivatives usually demonstrate improved biological and pharmacological activities, which make them promising candidates for drug discovery and development. The transfer reactions of a prenyl moiety from a prenyl donor, e.g. dimethylallyl diphosphate (DMAPP), to an acceptor is catalysed by prenyltransferases. One special group of such enzymes uses DMAPP and tryptophan as substrates with dimethylallyltryptophans as reaction products and functions therefore as dimethylallyltryptophan synthases (DMATSs)...
October 18, 2016: Organic & Biomolecular Chemistry
Y Mohini, R B N Prasad, M S L Karuna, Y Poornachandra, C Ganesh Kumar
A series of novel ricinoleic acid based lipoamino acid derivatives were synthesized from (Z)-methyl-12-aminooctadec-9-enoate and different l-amino acids (glycine, alanine, phenyl alanine, valine, leucine, isoleucine, proline and tryptophan). The structures of all the prepared compounds were characterized by (1)H NMR, (13)C NMR and mass spectral studies. The title compounds were evaluated for their antimicrobial and anti-biofilm activities. Among all the derivatives, compound 7a (Z)-methyl-12-(2-aminoacetamido)octadec-9-enoate exhibited promising antibacterial activity (MIC, 3...
September 28, 2016: Bioorganic & Medicinal Chemistry Letters
Angela Maria Amorini, Giacomo Lazzarino, Valentina Di Pietro, Stefano Signoretti, Giuseppe Lazzarino, Antonio Belli, Barbara Tavazzi
In this study, concentrations of free amino acids (FAA) and amino group containing compounds (AGCC) following graded diffuse traumatic brain injury (mild TBI, mTBI; severe TBI, sTBI) were evaluated. After 6, 12, 24, 48 and 120 hr aspartate (Asp), glutamate (Glu), asparagine (Asn), serine (Ser), glutamine (Gln), histidine (His), glycine (Gly), threonine (Thr), citrulline (Cit), arginine (Arg), alanine (Ala), taurine (Tau), γ-aminobutyrate (GABA), tyrosine (Tyr), S-adenosylhomocysteine (SAH), l-cystathionine (l-Cystat), valine (Val), methionine (Met), tryptophane (Trp), phenylalanine (Phe), isoleucine (Ile), leucine (Leu), ornithine (Orn), lysine (Lys), plus N-acetylaspartate (NAA) were determined in whole brain extracts (n = 6 rats at each time for both TBI levels)...
October 3, 2016: Journal of Cellular and Molecular Medicine
Solange Abdulnour-Nakhoul, Trang Le, Edd Rabon, L Lee Hamm, Nazih L Nakhoul
Renal Rhbg is localized to the basolateral membrane of intercalated cells and is involved in NH3/NH4+ transport. The structure of Rhbg is not yet resolved however a high-resolution crystal structure of AmtB, a bacterial homologue of Rh, has been determined. We aligned the sequence of Rhbg to AmtB and identified important sites of Rhbg that may affect transport. Our analysis positioned three conserved amino acids, Histidine-183 (H183), Histidine-342 (H342) and Tryptophan-230 (W230), within the hydrophobic pore where they presumably serve to control NH3 transport...
September 28, 2016: American Journal of Physiology. Renal Physiology
Theodoros Eleftheriadis, Georgios Pissas, Maria Sounidaki, Konstantina Tsogka, Nikolaos Antoniadis, Georgia Antoniadi, Vassilios Liakopoulos, Ioannis Stefanidis
Indoleamine 2,3-dioxygenase (IDO) is expressed in antigen-presenting cells and by degrading L-tryptophan along the kynurenine pathway suppresses CD4+ T-cell proliferation, induces apoptosis and promotes differentiation towards a regulatory as opposed to an effector phenotype. Recent findings revealed that the above effects may be mediated through alterations in T-cell metabolism. In this study, the effect of IDO on fatty acid β-oxidation in CD4+ T-cells was evaluated in human mixed lymphocyte reactions (MLRs) using the IDO inhibitor, 1-DL-methyl-tryptophan...
September 23, 2016: International Journal of Molecular Medicine
Josephine F Trott, Jeffrey Kim, Omran Abu Aboud, Hiromi Wettersten, Benjamin Stewart, Grace Berryhill, Francisco Uzal, Russell C Hovey, Ching-Hsien Chen, Katie Anderson, Ashley Graef, Aaron L Sarver, Jaime F Modiano, Robert H Weiss
Renal cell carcinoma (RCC) is increasing in incidence, and a complete cure remains elusive. While immune-checkpoint antibodies are promising, interferon-based immunotherapy has been disappointing. Tryptophan metabolism, which produces immunosuppressive metabolites, is enhanced in RCC. Here we show indolamine-2,3-dioxygenase-1 (IDO1) expression, a kynurenine pathway enzyme, is increased not only in tumor cells but also in the microenvironment of human RCC compared to normal kidney tissues. Neither kynurenine metabolites nor IDO inhibitors affected the survival or proliferation of human RCC or murine renal cell adenocarcinoma (RENCA) cells in vitro...
August 27, 2016: Oncotarget
Eoin Sherwin, Valentina Gigliucci, Andrew Harkin
OBJECTIVE: The regional specific modulation of neuronal activation following drug administration is of interest to determine brain areas involved in the behavioural effects of experimental test compounds. In the current investigation the effects of the L-arginine related NOS inhibitor N(ω)-l-nitroarginine (L-NA) and the structurally unrelated selective neuronal NOS inhibitor 1-(2-Trifluoro-methyl-phenyl) imidazole (TRIM) were assessed in the rat for changes in regional c-FOS immunoreactivity, a marker of neuronal activation, upon exposure to the forced swimming test (FST)...
January 1, 2017: Behavioural Brain Research
Astrid Knuhtsen, Baptiste Legrand, Olivier Van der Poorten, Muriel Amblard, Jean Martinez, Steven Ballet, Jesper L Kristensen, Daniel Sejer Pedersen
Protein arginine N-methyl transferases (PRMTs) belong to a family of enzymes that modulate the epigenetic code through modifications of histones. In the present study, peptides emerging from a phage display screening were modified in the search for PRMT inhibitors through substitution with non-proteinogenic amino acids, N-alkylation of the peptide backbone, and incorporation of constrained dipeptide mimics. One of the modified peptides (23) showed an increased inhibitory activity towards several PRMTs in the low μm range and the conformational preference of this peptide was investigated and compared with the original hit using circular dichroism and NMR spectroscopy...
September 19, 2016: Chemistry: a European Journal
Proteesh Rana, Amit K Sharma, Smita Jain, Pravin Deshmukh, S K Bhattacharya, B D Banerjee, Pramod K Mediratta
BACKGROUND: The inflammatory response system has been implicated in the pathophysiology of major depression. The pro-inflammatory cytokines like interferon-γ induce the enzyme indoleamine-2,3-dioxygenase (IDO) of the kynurenine pathway of tryptophan metabolism. The induction of IDO reduces the availability of tryptophan for serotonin synthesis. Furthermore, the metabolites of kynurenine pathway have neurotoxic property, which along with decreased serotonin may account for depression-like illness...
August 5, 2016: Journal of Basic and Clinical Physiology and Pharmacology
Sanjeewani Sooriyaarachchi, René Chofor, Martijn D P Risseeuw, Terese Bergfors, Jenny Pouyez, Cynthia S Dowd, Louis Maes, Johan Wouters, T Alwyn Jones, Serge Van Calenbergh, Sherry L Mowbray
Blocking the 2-C-methyl-d-erythrithol-4-phosphate pathway for isoprenoid biosynthesis offers new ways to inhibit the growth of Plasmodium spp. Fosmidomycin [(3-(N-hydroxyformamido)propyl)phosphonic acid, 1] and its acetyl homologue FR-900098 [(3-(N-hydroxyacetamido)propyl)phosphonic acid, 2] potently inhibit 1-deoxy-d-xylulose-5-phosphate reductoisomerase (Dxr), a key enzyme in this biosynthetic pathway. Arylpropyl substituents were introduced at the β-position of the hydroxamate analogue of 2 to study changes in lipophilicity, as well as electronic and steric properties...
September 20, 2016: ChemMedChem
Janis J Füller, René Röpke, Joern Krausze, Kim E Rennhack, Nils P Daniel, Wulf Blankenfeldt, Stefan Schulz, Dieter Jahn, Jürgen Moser
Violacein is a natural purple pigment of Chromobacterium violaceum with potential medical applications as antimicrobial, antiviral, and anticancer drugs. The initial step of violacein biosynthesis is the oxidative conversion of l-tryptophan into the corresponding α-imine catalyzed by the flavoenzyme l-tryptophan oxidase (VioA). A substrate-related (3-(1H-indol-3-yl)-2-methylpropanoic acid) and a product-related (2-(1H-indol-3-ylmethyl)prop-2-enoic acid) competitive VioA inhibitor was synthesized for subsequent kinetic and x-ray crystallographic investigations...
September 16, 2016: Journal of Biological Chemistry
V V Yasnetsov, E G Tsublova, Vic V Yasnetsov, S Ya Skachilova, S K Karsanova, Yu V Ivanov
It was established that a new 3-hydroxypyridine (3-HP) derivative, 2-ethyl-6-methyl-3-hydroxypyridine L-aspartate (3-HP), in small doses (1 and 5 mg/kg) increased physical performance in treadmill and swimming tests on rats. The new substance showed greater or equal effects compared to the reference actoprotector drugs metaprot and ladasten in much higher doses. The gluconeogenesis inhibitor tryptophan significantly (74 ± 5%, p < 0.01) prevented this stimulatory effect of 3-HPA in the treadmill test on rats...
2016: Eksperimental'naia i Klinicheskaia Farmakologiia
Eser Lay Ergün, Serap Saygi, Dilek Yalnizoglu, Kader Karli Oguz, Belkis Erbas
In epilepsy, a detailed history, blood chemistry, routine electroencephalography, and brain MRI are important for the diagnosis of seizure type or epilepsy syndrome for the decision of appropriate drug treatment. Although antiepileptic drugs are mostly successful for controlling epileptic seizures, 20%-30% patients are resistant to medical treatment and continue to have seizures. In this intractable patient group, surgical resection is the primarily preferred treatment option. This particular group of patients should be referred to the epilepsy center for detailed investigation and further treatment...
July 2016: Seminars in Nuclear Medicine
Airi Sekine, Yusuke Kuroki, Tomomi Urata, Noriyuki Mori, Tsutomu Fukuwatari
The tryptophan metabolite, kynurenic acid (KYNA), is a preferential antagonist of the α7 nicotinic acetylcholine receptor and N-methyl-D-aspartic acid receptor at endogenous brain concentrations. Recent studies have suggested that increases of brain KYNA levels are involved in psychiatric disorders such as schizophrenia and depression, and regulation of KYNA production has become a new target for treatment of these diseases. Kynurenine (KYN), the immediate precursor of KYNA, is transported into astrocytes via large neutral amino acid transporters (LATs)...
September 2016: Neurochemical Research
Anthony R Guastella, Sharon K Michelhaugh, Neil V Klinger, William J Kupsky, Lisa A Polin, Otto Muzik, Csaba Juhász, Sandeep Mittal
Increasing evidence demonstrates the immunosuppressive kynurenine pathway's (KP) role in the pathophysiology of human gliomas. To study the KP in vivo, we used the noninvasive molecular imaging tracer α-[(11)C]-methyl-l-tryptophan (AMT). The AMT-positron emission tomography (PET) has shown high uptake in high-grade gliomas and predicted survival in patients with recurrent glioblastoma (GBM). We generated patient-derived xenograft (PDX) models from dissociated cells, or tumor fragments, from 5 patients with GBM...
2016: Molecular Imaging
Xuan Huang, Xia Xiao, Robert J Gillies, Haibin Tian
(11)C-alpha-methyl-l-tryptophan ([(11)C]AMT), a tryptophan metabolism PET tracer, has successfully been employed for brain serotonin pathway and indoleamine 2,3-dioxygenase (IDO) pathway related tumor imaging. We here report a reliable, automated procedure for routine synthesis of [(11)C]AMT based on an Eckert and Ziegler Modular-Lab system. The semi-preparative HPLC was incorporated into the system to improve chemical purity and specific activity. The 6-step radiosynthesis followed by HPLC-purification provided [(11)C]AMT in 5...
May 2016: Nuclear Medicine and Biology
Shuuhei Takahashi, Hideaki Iizuka, Ryousuke Kuwabara, Yoko Naito, Tatsuya Sakamoto, Aya Miyagi, Mayu Onozato, Hideaki Ichiba, Takeshi Fukushima
The concentrations of l-tryptophan (Trp) and the metabolite l-kynurenine (KYN) can be used to evaluate the in-vivo activity of indoleamine 2,3-dioxygenase (IDO) and tryptophan 2,3-dioxygenase (TDO). As such, a novel method involving derivatization of l-Trp and l-KYN with (R)-4-(3-isothiocyanatopyrrolidin-1-yl)-7-(N,N-dimethylaminosulfonyl)-2,1,3-benzoxadiazole (DBD-PyNCS) and separation by high-performance liquid chromatography (HPLC) with tandem mass spectrometric (MS/MS) detection on a triazole-bonded column (Cosmosil HILIC®) was developed to determine their concentrations...
September 2016: Biomedical Chromatography: BMC
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