Theanine, Antistress Amino Acid in Tea Leaves, Causes Hippocampal Metabolic Changes and Antidepressant Effects in Stress-Loaded Mice

By comprehensively measuring changes in metabolites in the hippocampus of stress-loaded mice, we investigated the reasons for stress vulnerability and the effect of theanine, i.e., an abundant amino acid in tea leaves, on the metabolism. Stress sensitivity was higher in senescence-accelerated mouse prone 10 (SAMP10) mice than in normal ddY mice when these mice were loaded with stress on the basis of territorial consciousness in males. Group housing was used as the low-stress condition reference. Among the statistically altered metabolites, depression-related kynurenine and excitability-related histamine were significantly higher in SAMP10 mice than in ddY mice. In contrast, carnosine, which has antidepressant-like activity, and ornithine, which has antistress effects, were significantly lower in SAMP10 mice than in ddY mice. The ingestion of theanine, an excellent antistress amino acid, modulated the levels of kynurenine, histamine, and carnosine only in the stress-loaded SAMP10 mice and not in the group-housing mice. Depression-like behavior was suppressed in mice that had ingested theanine only under stress loading. Taken together, changes in these metabolites, such as kynurenine, histamine, carnosine, and ornithine, were suggested to be associated with the stress vulnerability and depression-like behavior of stressed SAMP10 mice. It was also shown that theanine action appears in the metabolism of mice only under stress loading.

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Integrated Metabolome and Transcriptome Analyses Reveal Etiolation-Induced Metabolic Changes Leading to High Amino Acid Contents in a Light-Sensitive Japanese Albino Tea Cultivar

Frontiers in Plant Science ◽

10.3389/fpls.2020.611140 ◽

2021 ◽

Vol 11 ◽

Author(s):

Hiroto Yamashita ◽

Yuka Kambe ◽

Megumi Ohshio ◽

Aya Kunihiro ◽

Yasuno Tanaka ◽

...

Keyword(s):

Amino Acid ◽

Protein Degradation ◽

Urea Cycle ◽

Metabolic Changes ◽

Nitrogen Excretion ◽

Tea Leaves ◽

Arginase 1 ◽

High Amino Acid ◽

Transcriptome Analyses ◽

Tea Cultivar

Plant albinism causes the etiolation of leaves because of factors such as deficiency of chloroplasts or chlorophylls. In general, albino tea leaves accumulate higher free amino acid (FAA) contents than do conventional green tea leaves. To explore the metabolic changes of etiolated leaves (EL) in the light-sensitive Japanese albino tea cultivar “Koganemidori,” we performed integrated metabolome and transcriptome analyses by comparing EL with green leaves induced by bud-sport mutation (BM) or shading treatments (S-EL). Comparative omics analyses indicated that etiolation-induced molecular responses were independent of the light environment and were largely influenced by the etiolation itself. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment and pathway analyses revealed the downregulation of genes involved in chloroplast development and chlorophyll biosynthesis and upregulation of protein degradation-related pathways, such as the ubiquitin-proteasome system and autophagy in EL. Metabolome analysis showed that most quantified FAAs in EL were highly accumulated compared with those in BM and S-EL. Genes involved in the tricarboxylic acid (TCA) cycle, nitrogen assimilation, and the urea cycle, including the drastically downregulated Arginase-1 homolog, which functions in nitrogen excretion for recycling, showed lower expression levels in EL. The high FAA contents in EL might result from the increased FAA pool and nitrogen source contributed by protein degradation, low N consumption, and stagnation of the urea cycle rather than through enhanced amino acid biosynthesis.

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Environmental warming induces behavioral and metabolic changes in a freshwater crustacean − aeglids as a model organism

Annales de Limnologie - International Journal of Limnology ◽

10.1051/limn/2017032 ◽

2018 ◽

Vol 54 ◽

pp. 7 ◽

Cited By ~ 1

Author(s):

Gláucia Bolzan Cogo ◽

Cristiane Biasi ◽

Eduardo Stringini Severo ◽

Vania Loro ◽

Sandro Santos

Keyword(s):

Amino Acid ◽

Model Organism ◽

Metabolic Changes ◽

Activity Level ◽

Ecological Processes ◽

Leaf Consumption ◽

Extra Energy ◽

Different Temperatures ◽

Freshwater Crustacean ◽

Save Energy

Ecological processes in small-order streams are dependent on their community. A threat to the appropriate functioning of these processes is the water warming of streams since changes in temperature can modify the behavior, abundance, and distribution of the species. A way to predict the consequences of global warming on ecological processes in these ecosystems is to study their aquatic community. Here we evaluated behavioral and metabolic changes in Aegla longirostri at different temperatures (21 °C and 24 °C). Experiments were performed in laboratory conditions. We calculated leaf consumption and quantified glycogen, protein and amino acid composition in the hepatopancreas. We also conducted a behavioral test to investigate the activity level of aeglids. Leaf consumption did not differ between temperatures. However, the amount of protein was higher at 21 °C, and the amino acid and glycogen levels were greater at 24 °C. In the present study we evaluated only the activity of hepatopancreas, so we can assume that the organ may have used glucose through the breakdown of glycogen and also performing some protein break. However, this hypothesis needs to be confirmed by checking for muscle activity. Animals kept at 24 °C showed a lower level of activity. This strategy possibly occurs to save energy, as in elevated temperature crustaceans spend extra energy to maintain their homeostasis. This study indicates that a future increase temperature of streams will impact the populations of aeglids by changing their metabolism and behavior.

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RP-HPLC Determination of Tiger Nut and Orgeat Amino Acid Contents

Food Science and Technology International ◽

10.1177/1082013205051266 ◽

2005 ◽

Vol 11 (1) ◽

pp. 33-40 ◽

Cited By ~ 23

Author(s):

L. Bosch ◽

A. Alegría ◽

R. Farré

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Amino Acid Profile ◽

African Origin ◽

Rp Hplc ◽

Precision And Accuracy ◽

Amino Acid Contents ◽

Tiger Nuts ◽

Abundant Amino Acid

The amino acid profile of 11 samples of tiger nuts ( Cyperus esculentusL.) grown in the area of “L'Horta Nord” in Valencia (Spain) and one sample of African origin were determined, along with the amino acid contents of 10 samples of natural orgeat from Valencia. Protein was hydrolysed by hydrochloric acid at 110 °C for 23 h, and amino acids were derivatised with AQC and determined by RP-HPLC with fluorescence detection. The chromatographic conditions were optimised. The analytical parameters (detection and quantification limits, precision and accuracy) showed the method to be sufficiently sensitive and reproducible for determining amino acids resistant to acid hydrolysis in tiger nuts and orgeat. Arginine was the most abundant amino acid in both tiger nuts and orgeat and the lowest contents corresponding to histidine and tyrosine. The essential amino acid contents of tiger nuts and orgeat protein were greater than those proposed in the protein standard for adults by the FAO/WHO, with the exception of histidine. No significant differences were found among the arginine, lysine and isoleucine amino acid contents in tiger nuts from Valencia, Alboraya and Alm‡ssera; nor were they found among amino acids in tiger nuts from Valencia and Alm‡ssera, with the exception of tyrosine.

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Vibrio harveyi Infection Significantly Alters Amino Acid and Carbohydrate Metabolism in Whiteleg Shrimp, Litopenaeus vannamei

Metabolites ◽

10.3390/metabo10060265 ◽

2020 ◽

Vol 10 (6) ◽

pp. 265

Author(s):

Seohee Ma ◽

Ahran Kim ◽

Wonho Lee ◽

Seonghye Kim ◽

Sujin Lee ◽

...

Keyword(s):

Amino Acid ◽

Carbohydrate Metabolism ◽

Litopenaeus Vannamei ◽

Energy Demand ◽

Vibrio Harveyi ◽

Late Phase ◽

Magic Angle Spinning ◽

Metabolic Changes ◽

Shrimp Farming ◽

Magic Angle

Vibrio harveyi is one of the pathogens that threaten the shrimp farming industry. However, metabolic changes induced by V. harveyi infection in shrimp remain unknown. In this study, we first conducted high resolution-magic angle spinning (HR-MAS) nuclear magnetic resonance (NMR)-based metabolomics studies on gill, hepatopancreas, and haemolymph of V. harveyi-infected white leg shrimp, Litopenaeus vannamei. Using multivariate statistical analysis, we observed a clear separation between the early (3 and 9 h post-injection (hpi)) and late phases (24, 72 and 144 hpi) of the infection in all tissues. Moreover, metabolic changes in response to V. harveyi infection were faster in the haemolymph in the early phase and significantly changed in the late phase of the infection in the gills. Extensive changes were observed in the hepatopancreas, with 24 hpi being the turning point of progression from early to late phase infection in the hepatopancreas. V. harveyi infection increased the energy demand in L. vannamei and the amino acid and carbohydrate metabolism pathways also exhibited significant changes depending on the tissue. Thus, each tissue displayed different metabolic changes, depending on the progress of the infection.

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Facilitated Neurogenesis in the Developing Hippocampus After Intake of Theanine, an Amino Acid in Tea Leaves, and Object Recognition Memory

Cellular and Molecular Neurobiology ◽

10.1007/s10571-011-9707-0 ◽

2011 ◽

Vol 31 (7) ◽

pp. 1079-1088 ◽

Cited By ~ 28

Author(s):

Atsushi Takeda ◽

Kazuhiro Sakamoto ◽

Haruna Tamano ◽

Kotaro Fukura ◽

Naoto Inui ◽

...

Keyword(s):

Object Recognition ◽

Amino Acid ◽

Recognition Memory ◽

Tea Leaves ◽

Object Recognition Memory

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Structure and substrate specificity determinants of the taurine biosynthetic enzyme cysteine sulphinic acid decarboxylase

10.1101/2020.09.25.308866 ◽

2020 ◽

Author(s):

Elaheh Mahootchi ◽

Arne Raasakka ◽

Weisha Luan ◽

Gopinath Muruganandam ◽

Remy Loris ◽

...

Keyword(s):

Amino Acid ◽

Substrate Specificity ◽

Active Site ◽

Ph Regulation ◽

Enzymatic Oxidation ◽

Acid Decarboxylase ◽

Critical Determinant ◽

Signalling Molecules ◽

Binding Cavity ◽

Abundant Amino Acid

AbstractPyridoxal 5′-phosphate (PLP) is an important cofactor for amino acid decarboxylases with many biological functions, including the synthesis of signalling molecules, such as serotonin, dopamine, histamine, γ-aminobutyric acid, and taurine. Taurine is an abundant amino acid with multiple physiological functions, including osmoregulation, pH regulation, antioxidative protection, and neuromodulation. In mammalian tissues, taurine is mainly produced by decarboxylation of cysteine sulphinic acid to hypotaurine, catalysed by the PLP-dependent cysteine sulphinic acid decarboxylase (CSAD), followed by non-enzymatic oxidation of the product to taurine. We determined the crystal structure of mouse CSAD and compared it to other PLP-dependent decarboxylases in order to identify determinants of substrate specificity and catalytic activity. Recognition of the substrate involves distinct side chains forming the substrate-binding cavity. In addition, the backbone conformation of a buried active-site loop appears to be a critical determinant for substrate side chain binding in PLP-dependent decarboxylases. Phe94 was predicted to affect substrate specificity, and its mutation to serine altered both the catalytic properties of CSAD and its stability. Using small-angle X-ray scattering, we further showed that similarly to its closest homologue, GADL1, CSAD presents open/close motions in solution. The structure of apo-CSAD indicates that the active site gets more ordered upon internal aldimine formation. Taken together, the results highlight details of substrate recognition in PLP-dependent decarboxylases and provide starting points for structure-based inhibitor design with the aim of affecting the biosynthesis of taurine and other abundant amino acid metabolites.

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The Uniqueness of Tryptophan in Biology: Properties, Metabolism, Interactions and Localization in Proteins

International Journal of Molecular Sciences ◽

10.3390/ijms21228776 ◽

2020 ◽

Vol 21 (22) ◽

pp. 8776 ◽

Cited By ~ 1

Author(s):

Sailen Barik

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Structural Features ◽

Ring Structure ◽

Side Chain ◽

Aromatic Side Chain ◽

Single Ring ◽

Energy Consuming ◽

Animal Diet ◽

Abundant Amino Acid

Tryptophan (Trp) holds a unique place in biology for a multitude of reasons. It is the largest of all twenty amino acids in the translational toolbox. Its side chain is indole, which is aromatic with a binuclear ring structure, whereas those of Phe, Tyr, and His are single-ring aromatics. In part due to these elaborate structural features, the biosynthetic pathway of Trp is the most complex and the most energy-consuming among all amino acids. Essential in the animal diet, Trp is also the least abundant amino acid in the cell, and one of the rarest in the proteome. In most eukaryotes, Trp is the only amino acid besides Met, which is coded for by a single codon, namely UGG. Due to the large and hydrophobic π-electron surface area, its aromatic side chain interacts with multiple other side chains in the protein, befitting its strategic locations in the protein structure. Finally, several Trp derivatives, namely tryptophylquinone, oxitriptan, serotonin, melatonin, and tryptophol, have specialized functions. Overall, Trp is a scarce and precious amino acid in the cell, such that nature uses it parsimoniously, for multiple but selective functions. Here, the various aspects of the uniqueness of Trp are presented in molecular terms.

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The purification and properties of the lectin from potato tubers, a hydroxyproline-containing glycoprotein

Biochemical Journal ◽

10.1042/bj1350307 ◽

1973 ◽

Vol 135 (2) ◽

pp. 307-314 ◽

Cited By ~ 172

Author(s):

Anthony K. Allen ◽

Albert Neuberger

Keyword(s):

Amino Acid ◽

Wheat Germ ◽

Gel Filtration ◽

Indirect Evidence ◽

Basic Amino Acid ◽

Potato Tubers ◽

Molecular Weights ◽

Purification And Properties ◽

Sepharose 4B ◽

Abundant Amino Acid

1. Potato lectin has been purified and shown to be a glycoprotein containing about 50% of carbohydrate. Most of the sugar residues (92%) are arabinose; small amounts of galactose, glucose and glucosamine are also present. 2. The most abundant amino acid is hydroxyproline (16% of the residues), 11.5% of the residues are half-cystine and phenylalanine is absent. The lectin also contains about one residue/molecule of a basic amino acid, not usually found in proteins, which has been tentatively identified as ornithine. There is indirect evidence that the components of the glycoprotein are linked through hydroxyproline and arabinose. 3. By gel filtration in 6m-guanidine–HCl on Sepharose 4B, it was found that both the native glycoprotein and its S-carboxymethylated derivative had subunit molecular weights of 46000 (±5000). In a non-denaturing solution, two of these units appear to be associated. 4. The lectin is specifically inhibited in its agglutination reaction by oligosaccharides that contain N-acetylglucosamine. Its specificity is similar to, but not identical with, that of wheat-germ agglutinin.

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Occurrence, Biosynthesis and Metabolism of Theanine (γ-Glutamyl-L-ethylamide) in Plants: A Comprehensive Review

Natural Product Communications ◽

10.1177/1934578x1501000525 ◽

2015 ◽

Vol 10 (5) ◽

pp. 1934578X1501000 ◽

Cited By ~ 14

Author(s):

Hiroshi Ashihara

Keyword(s):

Amino Acid ◽

Light Intensity ◽

Glutamic Acid ◽

Camellia Sinensis ◽

Xylem Sap ◽

Tea Leaves ◽

Major Site ◽

Protein Amino Acid ◽

Comprehensive Review ◽

Young Leaves

Theanine (γ-glutamyl-L-ethylamide) is the most abundant non-protein amino acid in tea leaves. In addition to Camellia sinensis, theanine occurs in several plants belonging to the Ericales. Biosynthesis of theanine from glutamic acid and ethylamine by theanine synthetase is present in all organs of tea seedlings, but roots are the major site of theanine biosynthesis in adult tea trees. Theanine is transported from roots to young leaves via the xylem sap. Theanine is hydrolysed to glutamic acid and ethylamine in leaves. Ethylamine produced from theanine is predominantly used for catechin biosynthesis. Concentration of ammonia and light intensity influence the biosynthesis and degradation of theanine, respectively. Biosynthesis, translocation and degradation of theanine and related enzymes and genes are reviewed.

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Endogenous amino acid flows at the terminal ileum of broilers, layers and adult roosters

Animal Science ◽

10.1017/s1357729800090123 ◽

2004 ◽

Vol 79 (2) ◽

pp. 265-271 ◽

Cited By ~ 41

Author(s):

V. Ravindran ◽

W. H. Hendriks

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Glutamic Acid ◽

Terminal Ileum ◽

Crude Protein ◽

Amino Acid Profile ◽

The Other ◽

Endogenous Protein ◽

Abundant Amino Acid ◽

Endogenous Amino Acid

AbstractEndogenous flows of nitrogen and amino acids at the terminal ileum of broilers (6 weeks old), layers (70 weeks old) and adult roosters (70 weeks old) were determined using the peptide alimentation method. The ileal endogenous output of nitrogen and total amino acids in broilers, layers and roosters, expressed as mg/kg dry matter intake, were similar (F > 0-05). Endogenous flows were similar (F > 0-05) for nine of the 17 amino acids analysed, but the flows of serine, glutamic acid, proline, alanine, isoleucine, tyrosine, arginine and methionine differed (P < 0-05) among the classes of chickens. The amino acid profile of endogenous protein, expressed asg/100 g crude protein, did not differ (F > 0-05) between the three classes of chickens, except for serine, glutamic acid, proline and isoleucine. The concentrations of proline were higher (F < 0-05) in broilers, compared with the other two groups. The concentrations of glutamic acid in layers were lower (F < 0-05) than the other two groups. The concentrations of serine and isoleucine were higher (F < 0-05) in roosters than the other two groups. In all three groups, the most abundant amino acid in the ileal endogenous protein was glutamic acid, followed by aspartic acid, proline, serine, glycine and threonine. The present study provides estimates for endogenous amino acid flow at the terminal ileum in broilers, layers and adult roosters under normal physiological conditions.

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