scholarly journals Regional Brain Analysis of Modified Amino Acids and Dipeptides during the Sleep/Wake Cycle

Metabolites ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 21
Author(s):  
Theodosia Vallianatou ◽  
Nicholas B. Bèchet ◽  
Mario S. P. Correia ◽  
Iben Lundgaard ◽  
Daniel Globisch
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Acid Metabolism ◽  
Aromatic Amino Acids ◽  
Brain Regions ◽  
Detection And Identification ◽  
The Central Nervous System ◽  
Neurophysiological Mechanisms ◽  
Amino Acid Analogues ◽  
The Brain

Sleep is a state in which important restorative and anabolic processes occur. Understanding changes of these metabolic processes during the circadian rhythm in the brain is crucial to elucidate neurophysiological mechanisms important for sleep function. Investigation of amino acid modifications and dipeptides has recently emerged as a valuable approach in the metabolic profiling of the central nervous system. Nonetheless, very little is known about the effects of sleep on the brain levels of amino acid analogues. In the present study, we examined brain regional sleep-induced alterations selective for modified amino acids and dipeptides using UPLC-MS/MS based metabolomics. Our approach enabled the detection and identification of numerous amino acid-containing metabolites in the cortex, the hippocampus, the midbrain, and the cerebellum. In particular, analogues of the aromatic amino acids phenylalanine, tyrosine and tryptophan were significantly altered during sleep in the investigated brain regions. Cortical levels of medium and long chain N-acyl glycines were higher during sleep. Regional specific changes were also detected, especially related to tyrosine analogues in the hippocampus and the cerebellum. Our findings demonstrate a strong correlation between circadian rhythms and amino acid metabolism specific for different brain regions that provide previously unknown insights in brain metabolism.

The amino acid metabolism of a developing insect cuticle: the larval cuticle and puparium of Calliphora vomitoria . I. Changes in amino acid composition during development

1958 ◽  
Vol 148 (931) ◽  
pp. 270-279 ◽  
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Amino Acid Composition ◽  
Acid Composition ◽  
Amino Acid Metabolism ◽  
Acid Metabolism ◽  
Aromatic Amino Acids ◽  
Larval Cuticle ◽  
Normal Larva ◽  
Normal Feeding

The amino acid composition of the developing larval cuticle and puparium of Calliphora vomitoria has been examined by means of paper chromatography. The most significant changes during development concern the aromatic amino acids. Phenylalanine and para -tyrosine apparently combine with the tanning quinone when the puparium hardens, and ortho -tyrosine is present for a brief period at about 7 days The presence of o -tyrosine, together with evidence resulting from the extraction of larval cuticles with water, gives rise to the suspicion that aromatic amino acids may be metabolized in the cuticle during development and give rise to hydroxylated products. The cuticle of ‘permanent larvae’, which fail to pupate even after the lapse of 2 to 3 weeks owing to the extirpation of Weismann’s ring before the end of the normal feeding period, has also been examined. Its amino acid composition shows none of the changes seen in the normal larva.

Intravenous Infusion of α-Oxoisocaproate: Influence on Amino Acid and Nitrogen Metabolism in Patients with Liver Cirrhosis

1982 ◽  
Vol 62 (3) ◽  
pp. 285-293 ◽  
Author(s):  
L. S. Eriksson ◽  
L. Hagenfeldt ◽  
J. Wahren
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Intravenous Infusion ◽  
Aromatic Amino Acids ◽  
Control Subjects ◽  
Catheter Technique ◽  
Healthy Control ◽  
And Control ◽  
The Brain ◽  
Amino Acid Concentrations

1. The metabolic effect of α-oxoisocaproate (4-methyl-2-oxovalerate) infusion was examined in six patients with cirrhosis and in nine healthy control subjects. The arterial concentrations of amino acids, urea, ammonia, insulin and catecholamines were determined in the basal state and during intravenous infusion of α-oxoisocaproate (300 μmol/min) for 150 min. The exchanges of amino acids and substrates across the splanchnic region, the brain and the leg were examined in the healthy subjects by a catheter technique. 2. Basal α-oxoisocaproate levels were similar in patients and control subjects. During infusion the concentrations of α-oxoisocaproate rose to 90–130 μmol/l; they were 20–35% lower in the patients. Arterial leucine concentration increased in both groups to 250–300 μmol/l. Valine and isoleucine concentrations decreased (50–60%) as did to a lesser extent the concentrations of aromatic amino acids and methionine. 3. Regional exchange of amino acids was not significantly influenced by α-oxoisocaproate infusion. Arterial urea concentration decreased (12%, P < 0.05) and ammonia levels rose (15–25%, P < 0.05) in both groups. In the patients both adrenaline (100%, P < 0.001) and noradrenaline concentrations were elevated (350%, P < 0.001) in the basal state; insulin levels were similar to those in control subjects. 4. It is concluded that α-oxoisocaproate is rapidly transaminated to leucine in patients with cirrhosis and in healthy control subjects. α-Oxoisocaproate infusion resembles leucine infusion in its influence on aromatic amino acid concentrations, but in addition it elicits increased ammonia levels and decreased urea formation.

scholarly journals Gut microbiota of mice putatively modifies amino acid metabolism in the host brain

2017 ◽  
Vol 117 (6) ◽  
pp. 775-783 ◽  
Author(s):  
Takahiro Kawase ◽  
Mao Nagasawa ◽  
Hiromi Ikeda ◽  
Shinobu Yasuo ◽  
Yasuhiro Koga ◽  
...  
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Gut Microbiota ◽  
Amino Acid Metabolism ◽  
Acid Metabolism ◽  
Plasma Concentrations ◽  
Brain Regions ◽  
Experimental Models ◽  
Specific Pathogen ◽  
Host Brain

AbstractRecently, it has been found that the gut microbiota influences functions of the host brain by affecting monoamine metabolism. The present study focused on the relationship between the gut microbiota and the brain amino acids. Specific pathogen-free (SPF) and germ-free (GF) mice were used as experimental models. Plasma and brain regions were sampled from mice at 7 and 16 weeks of age, and analysed for free d- and l-amino acids, which are believed to affect many physiological functions. At 7 weeks of age, plasma concentrations of d-aspartic acid (d-Asp), l-alanine (l-Ala), l-glutamine (l-Gln) and taurine were higher in SPF mice than in GF mice, but no differences were found at 16 weeks of age. Similar patterns were observed for the concentrations of l-Asp in striatum, cerebral cortex and hippocampus, and l-arginine (l-Arg), l-Ala and l-valine (l-Val) in striatum. In addition, the concentrations of l-Asp, d-Ala, l-histidine, l-isoleucine (l-Ile), l-leucine (l-Leu), l-phenylalanine and l-Val were significantly higher in plasma of SPF mice when compared with those of GF mice. The concentrations of l-Arg, l-Gln, l-Ile and l-Leu were significantly higher in SPF than in GF mice, but those of d-Asp, d-serine and l-serine were higher in some brain regions of GF mice than in those of SPF mice. In conclusion, the concentration of amino acids in the host brain seems to be dependent on presence of the gut microbiota. Amino acid metabolism in the host brain may be modified by manipulating microbiota communities.

Amino acid precursors of monoamine neurotransmitters and some factors influencing their supply to the brain

1976 ◽  
Vol 6 (2) ◽  
pp. 277-286 ◽  
Author(s):  
P. M. Daniel ◽  
S. R. Moorhouse ◽  
O. E. Pratt
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Aromatic Amino Acid ◽  
Aromatic Amino Acids ◽  
Mental States ◽  
Monoamine Neurotransmitters ◽  
Motor Disability ◽  
Neuropsychiatric Diseases ◽  
Amino Acid Precursors ◽  
The Brain

SynopsisThere is evidence that changes in the concentrations of the monoamine neurotransmitters within the brain are associated with changes in mental processes, with disorders of control of movement and with certain neuropsychiatric diseases. These neurotransmitters are synthesized in the brain from aromatic amino acid precursors that have to be obtained from the circulating blood. In this study some factors which alter the rates of entry of four amino acids (the important neurotransmitter precursors L-tyrosine and L-tryptophan, as well as L-phenylalanine and L-histidine) into the brain have been studied and the findings considered in relation to conditions in which the quantities of one or more of the monoamine neurotransmitters formed within the cerebral cells may be either too large or too small. Thus too little neurotransmitter will be formed if competition between amino acids for the carriers transporting them into the cerebral cells causes the exclusion of a large proportion of any of the aromatic amino acid precursors from the brain. For example, L-tryptophan is partially excluded from the brain if a raised level of any one of several other amino acids is maintained in the circulation. Of these, L-phenylalanine inhibits the transport of L-tryptophan into the brain most effectively, while aromatic amino acids in general exclude L-tryptophan more effectively than do other neutral amino acids.Over-production of one or more of the monoamine neurotransmitters is likely to occur when there is too much of one of the aromatic amino acid precursors in the brain cells as a result of abnormally high uptake from the blood, or as a result of their release by an excessive breakdown of the protein within these cells. Underproduction of neurotransmitters may occur in certain disease states, such as some aminoacidurias or Parkinsonism. We have listed some conditions associated with altered mental states or motor disability in which over- or under-production of monoamine neurotransmitters may occur and have tried to relate the findings in human disease with our experimental results.

scholarly journals Fungal Enzyme l-Lysine α-Oxidase Affects the Amino Acid Metabolism in the Brain and Decreases the Polyamine Level

2020 ◽  
Vol 13 (11) ◽  
pp. 398
Author(s):  
Elena V. Lukasheva ◽  
Marina G. Makletsova ◽  
Alexander N. Lukashev ◽  
Gulalek Babayeva ◽  
Anna Yu. Arinbasarova ◽  
...  
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Amino Acid Metabolism ◽  
Acid Metabolism ◽  
Tca Cycle ◽  
Polyamine Level ◽  
The Brain ◽  
Oxidative Species

The fungal glycoprotein l-lysine α-oxidase (LO) catalyzes the oxidative deamination of l-lysine (l-lys). LO may be internalized in the intestine and shows antitumor, antibacterial, and antiviral effects in vivo. The main mechanisms of its effects have been shown to be depletion of the essential amino acid l-lys and action of reactive oxidative species produced by the reaction. Here, we report that LO penetrates into the brain and is retained there for up to 48 h after intravenous injection, which might be explained by specific pharmacokinetics. LO actively intervenes in amino acid metabolism in the brain. The most significant impact of LO was towards amino acids, which are directly exposed to its action (l-lys, l-orn, l-arg). In addition, the enzyme significantly affected the redistribution of amino acids directly associated with the tricarboxylic acid (TCA) cycle (l-asp and l-glu). We discovered that the depletion of l-orn, the precursor of polyamines (PA), led to a significant and long-term decrease in the concentration of polyamines, which are responsible for regulation of many processes including cell proliferation. Thus, LO may be used to reduce levels of l-lys and PA in the brain.

The amino acid metabolism of a developing insect cuticle: the larval cuticle and puparium of Calliphora vomitoria . II. The non-specific hydroxylation of aromatic amino acids and the production of polyphenols by the cuticle

1958 ◽  
Vol 148 (931) ◽  
pp. 280-284 ◽  
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Amino Acid Metabolism ◽  
Acid Metabolism ◽  
Aromatic Amino Acids ◽  
Insect Cuticle ◽  
Larval Cuticle

The possibility that the larval cuticle of Calliphora vomitoria is capable of hydroxylating aromatic amino acids has been examined by incubation with phenylalanine and related amino acids. Hydroquinone and other dihydroxyphenols, and in addition trihydroxyphenols, have been recovered after incubation. The cuticle is also capable of forming hydroxylated products from tryptophan, making it clear that the process is non-specific.

Single Amino Acid Based Self-Assemblies of Cysteine and Methionine

2018 ◽  
Author(s):  
Nidhi Gour ◽  
Bharti Koshti ◽  
Chandra Kanth P. ◽  
Dhruvi Shah ◽  
Vivek Shinh Kshatriya ◽  
...  
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Self Assembly ◽  
Aromatic Amino Acids ◽  
Neutral Condition ◽  
Single Amino Acid ◽  
Binding Assays ◽  
Human Neuroblastoma ◽  
Cytotoxicity Assays ◽  
First Time

We report for the very first time self-assembly of Cysteine and Methionine to discrenible strucutres under neutral condition. To get insights into the structure formation, thioflavin T and Congo red binding assays were done which revealed that aggregates may not have amyloid like characteristics. The nature of interactions which lead to such self-assemblies was purported by coincubating assemblies in urea and mercaptoethanol. Further interaction of aggregates with short amyloidogenic dipeptide diphenylalanine (FF) was assessed. While cysteine aggregates completely disrupted FF fibres, methionine albeit triggered fibrillation. The cytotoxicity assays of cysteine and methionine structures were performed on Human Neuroblastoma IMR-32 cells which suggested that aggregates are not cytotoxic in nature and thus, may not have amyloid like etiology. The results presented in the manuscript are striking, since to the best of our knowledge,this is the first report which demonstrates that even non-aromatic amino acids (cysteine and methionine) can undergo spontaneous self-assembly to form ordered aggregates.

Biochemische Aspekte des Aminosäuren-Stoffwechsels bei Psoriasis vulgaris / Biochemical Aspects of Amino Acid Metabolism in Psoriasis vulgaris

1973 ◽  
Vol 28 (7-8) ◽  
pp. 449-451 ◽  
Author(s):  
G. Peter ◽  
H. Angst ◽  
U. Koch
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Free Amino Acids ◽  
Free Amino ◽  
Amino Acid Metabolism ◽  
Acid Metabolism ◽  
Psoriasis Vulgaris ◽  
Normal Subjects ◽  
Pathological Process

Free and protein-bound amino acids in serum and scales were investigated. In serum the bound amino acids of psoriatics are significantly higher with exception of Pro, Met, Tyr and Phe in contrast to normal subjects. For free amino acids the differences between normal subjects and psoriatics found in serum and scales are not significant. Results are discussed in relation to the single amino acids and the biochemical correlations are outlined which takes the pathological process as a basis.

Characterization of an isozyme of S-adenosylmethionine synthetase from rat liver

1984 ◽  
Vol 62 (5) ◽  
pp. 276-279 ◽  
Author(s):  
C. H. Lin ◽  
W. Chung ◽  
K. P. Strickland ◽  
A. J. Hudson
Keyword(s):  
Amino Acids ◽  
Molecular Weight ◽  
Amino Acid ◽  
Enzymatic Synthesis ◽  
Gel Filtration ◽  
Deae Cellulose ◽  
Aromatic Amino Acids ◽  
Adenosylmethionine Synthetase ◽  
Cellulose Column

An isozyme of S-adenosylmethionine synthetase has been purified to homogeneity by ammonium sulfate fractionation, DEAE-cellulose column chromatography, and gel filtration on a Sephadex G-200 column. The purified enzyme is very unstable and has a molecular weight of 120 000 consisting of two identical subunits. Amino acid analysis on the purified enzyme showed glycine, glutamate, and aspartate to be the most abundant and the aromatic amino acids to be the least abundant. It possesses tripolyphosphatase activity which can be stimulated five to six times by S-adenosylmethionine (20–40 μM). The findings support the conclusion that an enzyme-bound tripolyphosphate is an obligatory intermediate in the enzymatic synthesis of S-adenosylmethionine from ATP and methionine.

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