l-tryptophan

Age-related neuronal injury and oxidative damage are the predominant factors for neurodegenerative diseases like Alzheimer's disease (AD). The aim of this study was to explore whether chronic administration of d-galactose (d-gal) can cause neuronal injury and oxidative damage, and to investigate the neuroprotective and antioxidative effects of the active components (UPNO-1) from Korean pine nut (Pinus koraiensis). Two dosing regimens were designed, one for the evaluation of preventive effects in which the rats were simultaneously administrated d-gal and UPNO-1/fishoil for 12 weeks, the other for the evaluation of therapeutic effects in which the rats were given d-gal for 8 weeks before treated with UPNO-1/selegiline for 8 weeks...

Aryl hydrocarbon receptor (AhR) is a nuclear receptor that controls xenobiotic detoxification via induction of cytochrome P450 1A1 (CYP1A1) and regulates immune responses in the intestine. Metabolites of L-tryptophan activate AhR, which confers protection against intestinal inflammation. We tested the hypothesis that serotonin (5-HT) is an endogenous activator of AhR in intestinal epithelial cells. Treatment of Caco-2 monolayers with 5-HT induced CYP1A1 mRNA in a time- and concentration-dependent manner and also stimulated CYP1A1 activity...

Cognitive behavioral therapy (CBT) and selective serotonin reuptake inhibitors (SSRIs) are both effective treatments for some patients with obsessive-compulsive disorder (OCD), yet little is known about the neurochemical changes related to these treatment modalities. Here, we used positron emission tomography and the α-[11 C]methyl-L-tryptophan tracer to examine the changes in brain regional serotonin synthesis capacity in OCD patients following treatment with CBT or SSRI treatment. Sixteen medication-free OCD patients were randomly assigned to 12 weeks of either CBT or sertraline treatment...

Male and female early bovine embryos show dimorphic transcription that impacts metabolism. Individual release of metabolites was examined in a 24h single culture medium from Day-6 male and female morulae that developed to Day-7 expanded blastocysts. Embryos were produced in vitro, fertilized with a single bull and cultured in SOFaaci+6  g/L BSA. The embryonic sex was identified (amelogenin gene amplification). Embryos (N = 10 males and N = 10 females) and N = 6 blank samples (i.e. SOFaaci+6  g/L BSA incubated with no embryos) were collected from 3 replicates...

BACKGROUND: Research about improvement of epilepsy therapy is constantly growing. Valproyl-L-Phenylalanine (VPA-Phen) and N-valproyl-L-tryptophan (VPA-Tryp) were synthesized to increase the antiepileptic valproic acid efficacy. METHODS: VPA-Phen and VPA-Tryp were comparatively tested on CA1 hippocampal epileptiform bursting activity obtained by increasing potassium and lowering calcium and magnesium concentrations in the fluid perfusing rat brain slices. Each slice was treated with a single concentration (0...

Indoleamine 2,3-dioxygenase-1 (IDO1) mediates the degradation of L-tryptophan (L-Trp) and is constitutively expressed in the chorionic vascular endothelium of the human placenta with highest levels in the microvasculature. Given that endothelial expression of IDO1 has been shown to regulate vascular tone and blood pressure in mice under the condition of systemic inflammation, we asked whether IDO1 is also involved in the regulation of placental blood flow and if yes, whether this function is potentially impaired in intrauterine growth restriction (IUGR) and pre-eclampsia (PE)...

Two novel and two known compounds, 4-quinolylaldoxime and indole-3-aldehyde, were isolated from a reaction mixture consisting of D-glucose and L-tryptophan at physiological temperature and pH. The chemical structures of the two novel compounds were elucidated by spectroscopic analysis such as X-ray crystallography. One of the novel compound and the indole-3-aldehyde showed mutagenicity toward Salmonella typhimurium YG1024 with S9 mix. Furthermore, 4-quinolylaldoxime was detected from streptozotocin-induced diabetic rat plasma by LC-MS/MS analysis; however, the isolated compounds were not detected in rat diet extracts...

We report the enzymatic synthesis of the derivatives of L-tryptophan methylated in indole moiety and labeled with deuterium and tritium in the 2-position of side chain. For kinetic studies twelve isotopomers, i.e., 1'-methyl-[2-2 H]-, 1'-methyl-[2-3 H]-, 1'-methyl-[2-2 H/3 H]-, 2'-methyl-[2-2 H]-, 2'-methyl-[2-3 H]-, 2'-methyl-[2-2 H/3 H]-, 5'-methyl-[2-2 H]-, 5'-methyl-[2-3 H]-, 5'-methyl-[2-2 H/3 H]-, 7'-methyl-[2-2 H]-, 7'-methyl-[2-3 H]-, and 7'-methyl-[2-2 H/3 H]-L-tryptophan are obtained by the enzymatic coupling of the appropriate methylated indole moiety with S-methyl-L-cysteine catalyzed by the enzyme tryptophanase...

Hypocalcemia affects almost 50% of all dairy cows. Our laboratory has previously demonstrated that infusions of the serotonin precursor 5-hydroxy-l-tryptophan (5-HTP) increase circulating calcium concentrations in the Holstein transition cow. It is unknown whether feeding a negative DCAD diet alters the relationship between 5-HTP and hypocalcemia. The main objective of this study was to determine whether feeding a negative dietary cation-anion difference (-DCAD) diet before calving in conjunction with 5-HTP treatment could further diminish the magnitude of hypocalcemia at the time of calving...

Unlike metazoans, plants, bacteria, and fungi retain the enzymatic machinery necessary to synthesize the three aromatic amino acids, L¬-phenylalanine, L-tyrosine, and L-tryptophan de novo. In legumes, such as soybean, alfalfa, and common bean, prephenate dehydrogenase (PDH) catalyzes the tyrosine-insensitive biosynthesis of 4-hydroxyphenylpyruvate, a precursor to tyrosine. The three-dimensional structure of soybean PDH1 was recently solved in complex with the NADP+ cofactor. This structure allowed for the identification of both the cofactor- and ligand-binding sites...

It is now well established that GPR139, a G-protein coupled receptor exclusively expressed in the brain and pituitary, is activated by the essential amino acids L-tryptophan (L-Trp) and L-phenylalanine (L-Phe) via Gαq -coupling. The in vitro affinity and potency values of L-Trp and L-Phe are within the physiological concentration ranges of L-Trp and L-Phe. A recent paper suggests that adrenocorticotropic hormone (ACTH), α and β melanocyte stimulating hormones (α-MSH and β-MSH) and derivatives α-MSH1-9 /α-MSH1-10 can also activate GPR139 in vitro ...

An electrochemical sensor is described for the determination of L-tryptophan (TRP). The method is based on the use of a glassy carbon electrode (GCE) modified with a nanocomposite consisting of moss ball-like cerium-doped ZnO and functionalized multiwalled carbon nanotubes (Ce-ZnO/f-MWCNT). Ce-doped ZnO was synthesized by a low temperature hydrothermal method. The Ce-ZnO/f-MWCNT nanocomposite was characterized by X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, FTIR and field emission scanning electron microscopy...

The bulk solution properties of amphiphilic formulations are derivative of their self-assembly into higher ordered supramolecular assemblies known as micelles and of their ordering at the air-water interface. Exerting control over the surface-active properties of amphiphiles and their propensity to aggregate in pure water is most often fine-tuned by covalent modification of their molecular structure. Nevertheless structural constraints which limit the performance of amphiphiles do emerge when trying to develop more sophisticated systems which undergo for example, shape-defined controlled assembly and/or respond to external stimuli...

Two novel indole-tetramic acid alkaloids-griseofamine A (1) and griseofamine B (2)-and ( R)- N-(2-methylbutanoyl)-l-tryptophan (3), were isolated from the fungus Penicillium griseofulvum. Compounds 1 and 2 feature a 6/5/6/5 and 6/5/7/5 tetracyclic ring systems formed by the fusion of an indole unit and a tetramic acid via a six or seven-membered N-heterocyclic ring, respectively. The plausible biosynthetic pathways of 1-3 are proposed. Compound 1 shows a weak anti-inflammatory activity by inhibition of NO and TNF-α production...

We have studied the host-guest binding properties of a crown ether equipped, fluorescent perylene bisimide (PBI) receptor with a series of aromatic amino acids and dipeptides by UV/Vis, fluorescence and NMR spectroscopy. Fluorescence titration experiments showed that electron-rich aromatic amino acids L-tryptophan (L-Trp) and L-tyrosine (L-Tyr) as well as dipeptides containing these amino acids strongly quench the fluorescence of the electron-poor PBI molecule. Benesi-Hildebrand plots of fluorescence titration data confirmed the formation of host-guest complexes with 1:2 stoichiometry...

Lipoxygenases catalyze the oxygenation of polyunsaturated fatty acids and their derivatives to produce conjugated diene hydroperoxides. Soybean lipoxygenase-1 (SBLO-1) has been the subject of intensive structural and mechanistic study, but the manner in which this enzyme binds substrates is uncertain. Previous studies suggest that the fatty acyl group of the substrate binds in an internal cavity near the catalytic iron with the polar end at the surface of the protein or perhaps external to the protein. To test this model, we have investigated two pairs of enantiomeric N-linoleoylamino acids as substrates for SBLO-1...

OBJECTIVE: Because there are almost no standard all-in-one parenteral nutrition admixtures available for infants and children, the aim was to develop standard two-compartment parenteral nutrition bags for different weight categories based on the ESPGHAN/ESPEN (European Society of Paediatric Gastroenterology, Hepatology and Nutrition/European Society for Clinical Nutrition and Metabolism) guidelines. The 1 g/kg/d lipid version for the 3 to 10 kg weight category (PED1) was assessed for short- and long-term physicochemical stability with the ability to add additional electrolytes (PED1+E)...

Fluorescent DNA base analogs and intrinsic fluorophores are gaining importance for multiphoton microscopy and imaging, however, their quantitative nonlinear excitation properties have been poorly documented. Here we present the two-photon absorption (2PA) spectra of 2-aminopurine (2AP), 7-methyl guanosine (7MG), isoxanthopterin (IXP), 6-methyl isoxanthopterin (6MI), as well as L-tryptophan (L-trp) and 3-methylindole (3MI) in aqueous solution and some organic solvents measured in the wavelength range 550 - 810 nm using femtosecond two-photon excited fluorescence (2PEF) and nonlinear transmission (NLT) methods...

Background : It is assumed that plant growth regulators produced by beneficial bacterial species could also influence plant growth. IAA is a major plant growth regulator responsible for stimulation of plant growth. There are several microorganisms which are naturally responsible for L- tryptophan metabolism. Methods : In total, 56 indigenous morphologically distinct isolates from rice roots were selected and subsequently characterized with biochemical tests, 16S rRNA sequencing and plant growth promoting activities...

Differences in the taste profile of corn puffed products formulated with refined versus whole grain mix flour were characterized. The perceived bitter intensity was reported to be the main taste difference between the samples. Based on multidimensional sensory-guided fractionation techniques and subsequent identification by MS and NMR analysis, the primary bitter compounds identified in the whole grain sample were l-tryptophan, chaenorpine, N1 ,N5 -Di-[E]-p-coumaroyl-spermidine, and terrestribisamide. All compounds were reported to contribute to bitterness perception at the concentrations reported in the saliva after mastication of the extruded products; chaenorphine had the highest contribution to the perceived bitterness...