Submit to IJMS Review for IJMS Propose a Special Issue

Journal Menu

Journal Browser

Amino Acid Metabolism: Design, Nutrition, and Disorders

Special Issue Editors
Special Issue Information
Keywords
Published Papers

A special issue of International Journal of Molecular Sciences (ISSN 1422-0067). This special issue belongs to the section "Molecular Endocrinology and Metabolism".

Deadline for manuscript submissions: closed (30 November 2022) | Viewed by 14719

Share This Special Issue

Special Issue Editor

Prof. Dr. Enrique Meléndez-Hevia

E-Mail Website
Guest Editor

Instituto del Metabolismo Celular, Calle Manuel de Fallanº15, 38208 Tenerife, Canary Islands, La Laguna, Spain
Interests: cell metabolism; evolution and natural selection; phylogeny; evolution of metabolism; metabolic control theory (control analysis); degenerative and metabolic diseases (osteoarthritis; diabetes, hypertension, obesity (metabolic syndrome); cancer)
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Amino acid metabolism has attracted increased interest in recent years. Genomic data are clarifying many points about the design, evolution, and regulation of amino acids, and their interactions of different complexity with other pathways are a great field for computer modeling. All this, together with laboratory experiments and nutritional studies, is forcing us to review the concept of essential amino acids and to expand the list of the eight classic amino acids due to the consequent change of nutritional paradigms both for general cases and for specific needs, such as the development of or intense physical activity, as well as farm animals. It is also leading to a better understanding of the fact that amino acid deficiency can be the main cause of important metabolic and physiological disorders. On the other hand, this topic is not usually examined in as much detail as it deserves in textbooks compared to energy metabolism. Indeed, despite the fact that it is a live subject of research, and although various results have been obtained in recent years, very few reviews have been published. Thus, this Special Issue will also be an opportunity to update some aspects of this topic for educational purposes. This Special Issue will cover a wide variety of topics and approaches to this critical part of metabolism, from its evolution and design to its practical applications in nutrition.

Prof. Dr. Enrique Meléndez-Hevia
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. International Journal of Molecular Sciences is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. There is an Article Processing Charge (APC) for publication in this open access journal. For details about the APC please see here. Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

design and evolution of amino acid metabolism
genomics and metabolomics
regulation and control
review of the concept of essential amino acids
human nutrition
special needs of athletes

Published Papers (6 papers)

Download All Papers

Research

Jump to: Review

10 pages, 1462 KiB

Open AccessArticle

Evaluation of L-Alanine Metabolism in Bacteria and Whole-Body Distribution with Bacterial Infection Model Mice

by Yuka Muranaka, Miki Matsue, Asuka Mizutani, Masato Kobayashi, Kakeru Sato, Ami Kondo, Yuri Nishiyama, Shusei Ohata, Kodai Nishi, Kana Yamazaki, Ryuichi Nishii, Naoto Shikano, Shigefumi Okamoto and Keiichi Kawai

Int. J. Mol. Sci. 2023, 24(5), 4775; https://0-doi-org.brum.beds.ac.uk/10.3390/ijms24054775 - 1 Mar 2023

Cited by 2 | Viewed by 1582

Abstract

The World Health Organization has cautioned that antimicrobial resistance (AMR) will be responsible for an estimated 10 million deaths annually by 2050. To facilitate prompt and accurate diagnosis and treatment of infectious disease, we investigated the potential of amino acids for use as indicators of bacterial growth activity by clarifying which amino acids are taken up by bacteria during the various growth phases. In addition, we examined the amino acid transport mechanisms that are employed by bacteria based on the accumulation of labeled amino acids, Na⁺ dependence, and inhibitory effects using a specific inhibitor of system A. We found that ³H-L-Ala accurately reflects the proliferative activity of Escherichia coli K-12 and pathogenic EC-14 in vitro. This accumulation in E. coli could be attributed to the amino acid transport systems being different from those found in human tumor cells. Moreover, biological distribution assessed in infection model mice with EC-14 using ³H-L-Ala showed that the ratio of ³H-L-Ala accumulated in infected muscle to that in control muscle was 1.20. By detecting the growth activity of bacteria in the body that occurs during the early stages of infection by nuclear imaging, such detection methods may result in expeditious diagnostic treatments for infectious diseases. Full article

(This article belongs to the Special Issue Amino Acid Metabolism: Design, Nutrition, and Disorders)

► Show Figures

Figure 1

13 pages, 1838 KiB

Open AccessArticle

Theanine, a Tea-Leaf-Specific Amino Acid, Alleviates Stress through Modulation of Npas4 Expression in Group-Housed Older Mice

by Keiko Unno, Kyoko Taguchi, Tomokazu Konishi, Makoto Ozeki and Yoriyuki Nakamura

Int. J. Mol. Sci. 2023, 24(4), 3983; https://0-doi-org.brum.beds.ac.uk/10.3390/ijms24043983 - 16 Feb 2023

Cited by 1 | Viewed by 1448

Abstract

Group rearing is a common housing condition, but group-housed older mice show increased adrenal hypertrophy, a marker of stress. However, the ingestion of theanine, an amino acid unique to tea leaves, suppressed stress. We aimed to elucidate the mechanism of theanine’s stress-reducing effects using group-reared older mice. The expression of repressor element 1 silencing transcription factor (REST), which represses excitability-related genes, was increased in the hippocampus of group-reared older mice, whereas the expression of neuronal PAS domain protein 4 (Npas4), which is involved in the regulation of excitation and inhibition in the brain, was lower in the hippocampus of older group-reared mice than in same-aged two-to-a-house mice. That is, the expression patterns of REST and Npas4 were found to be just inversely correlated. On the other hand, the expression levels of the glucocorticoid receptor and DNA methyltransferase, which suppress Npas4 transcription, were higher in the older group-housed mice. In mice fed theanine, the stress response was reduced and Npas4 expression tended to be increased. These results suggest that Npas4 expression was suppressed by the increased expression of REST and Npas4 downregulators in the group-fed older mice, but that theanine avoids the decrease in Npas4 expression by suppressing the expression of Npas4 transcriptional repressors. Full article

(This article belongs to the Special Issue Amino Acid Metabolism: Design, Nutrition, and Disorders)

► Show Figures

Figure 1

18 pages, 2034 KiB

Open AccessArticle

Residual Amino Acid Imbalance in Rats during Recovery from Acute Thioacetamide-Induced Hepatic Encephalopathy Indicates Incomplete Healing

by Yevgeniya I. Shurubor, Alexander E. Rogozhin, Elena P. Isakova, Yulia I. Deryabina and Boris F. Krasnikov

Int. J. Mol. Sci. 2023, 24(4), 3647; https://0-doi-org.brum.beds.ac.uk/10.3390/ijms24043647 - 11 Feb 2023

Cited by 1 | Viewed by 1316

Abstract

The delayed consequences of the influence of hepatic encephalopathy (HE) on the metabolism of animals have not been studied enough. We have previously shown that the development of acute HE under the influence of the thioacetamide (TAA) toxin is accompanied by pathological changes in the liver, an imbalance in CoA and acetyl CoA, as well as a number of metabolites of the TCA cycle. This paper discusses the change in the balance of amino acids (AAs) and related metabolites, as well as the activity of glutamine transaminase (GTK) and ω-amidase enzymes in the vital organs of animals 6 days after a single exposure to TAA. The balance of the main AAs in blood plasma, liver, kidney, and brain samples of control (n = 3) and TAA-induced groups (n = 13) of rats that received the toxin at doses of 200, 400, and 600 mg/kg was considered. Despite the apparent physiological recovery of the rats at the time of sampling, a residual imbalance in AA and associated enzymes persisted. The data obtained give an idea of the metabolic trends in the body of rats after their physiological recovery from TAA exposure and may be useful for prognostic purposes when choosing the necessary therapeutic agents. Full article

(This article belongs to the Special Issue Amino Acid Metabolism: Design, Nutrition, and Disorders)

► Show Figures

Graphical abstract

11 pages, 2764 KiB

Open AccessArticle

Comparison of Tandem Mass Spectrometry and the Fluorometric Method—Parallel Phenylalanine Measurement on a Large Fresh Sample Series and Implications for Newborn Screening for Phenylketonuria

by Dasa Perko, Urh Groselj, Vanja Cuk, Ziga Iztok Remec, Mojca Zerjav Tansek, Ana Drole Torkar, Blaz Krhin, Ajda Bicek, Adrijana Oblak, Tadej Battelino and Barbka Repic Lampret

Int. J. Mol. Sci. 2023, 24(3), 2487; https://0-doi-org.brum.beds.ac.uk/10.3390/ijms24032487 - 27 Jan 2023

Cited by 6 | Viewed by 1777

Abstract

Phenylketonuria (PKU) was the first disease to be identified by the newborn screening (NBS) program. Currently, there are various methods for determining phenylalanine (Phe) values, with tandem mass spectrometry (MS/MS) being the most widely used method worldwide. We aimed to compare the MS/MS method with the fluorometric method (FM) for measuring Phe in the dried blood spot (DBS) and the efficacy of both methods in the NBS program. The FM was performed using a neonatal phenylalanine kit and a VICTOR2^TM D fluorometer. The MS/MS method was performed using a NeoBase^TM 2 kit and a Waters Xevo TQD mass spectrometer. The Phe values measured with the MS/MS method were compared to those determined by the FM. The cut-off value for the NBS program was set at 120 µmol/L for FM and 85 µmol/L for MS/MS. We analyzed 54,934 DBS. The measured Phe values varied from 12 to 664 µmol/L, with a median of 46 µmol/L for the MS/MS method and from 10 to 710 µmol/L, with a median of 70 µmol/L for the FM. The Bland–Altman analysis indicated a bias of −38.9% (−23.61 µmol/L) with an SD of 21.3% (13.89 µmol/L) when comparing the MS/MS method to the FM. The Phe value exceeded the cut-off in 187 samples measured with FM and 112 samples measured with MS/MS. The FM had 181 false positives, while the MS/MS method had 106 false positives. Our study showed that the MS/MS method gives lower results compared to the FM. Despite that, none of the true positives would be missed, and the number of false-positive results would be significantly lower compared to the FM. Full article

(This article belongs to the Special Issue Amino Acid Metabolism: Design, Nutrition, and Disorders)

► Show Figures

Figure 1

14 pages, 1851 KiB

Open AccessArticle

Analysis of Enzyme Activity and Cellular Function for the N80S and S480F Asparagine Synthetase Variants Expressed in a Child with Asparagine Synthetase Deficiency

by Stephen J. Staklinski, Sarah Snanoudj, Anne-Marie Guerrot, Catherine Vanhulle, François Lecoquierre, Soumeya Bekri and Michael S. Kilberg

Int. J. Mol. Sci. 2023, 24(1), 559; https://0-doi-org.brum.beds.ac.uk/10.3390/ijms24010559 - 29 Dec 2022

Cited by 3 | Viewed by 2750

Abstract

Asparagine Synthetase Deficiency (ASNSD) is a disease caused by mutations in asparagine synthetase (ASNS). Newborns exhibit microcephaly, intractable epileptic-like seizures, progressive brain atrophy, and axial hypotonia. ASNSD results in global developmental delays and premature death. The present report describes a 9-year-old child who is a compound heterozygote with ASNS mutations c.1439C > T and c.239A > G leading to variants p.S480F and p.N80S, respectively. When grown in a complete culture medium, primary fibroblasts from the child contained ASNS mRNA and protein levels similar to an unrelated wild-type fibroblast cell line. When the child’s fibroblasts were cultured for up to 72 h in a medium lacking asparagine, proliferation was reduced by about 50%. Purification of ASNS proteins harboring either the S480F or the N80S substitution had reduced enzymatic activity by 80% and 50%, respectively. Ectopic expression of either variant in ASNS-null Jensen rat sarcoma (JRS) cells did not support proliferation in the absence of medium-supplied asparagine, whereas expression of wild-type enzyme completely restored growth. These studies add to the list of pathogenic ASNS variants and use enzyme activity and protein expression in ASNS-null cells to expand our knowledge of the biological impact of mutations in the ASNS gene. Full article

(This article belongs to the Special Issue Amino Acid Metabolism: Design, Nutrition, and Disorders)

► Show Figures

Figure 1

Review

Jump to: Research

16 pages, 1061 KiB

Open AccessReview

The Tryptophan and Kynurenine Pathway Involved in the Development of Immune-Related Diseases

by Ai Tsuji, Yuka Ikeda, Sayuri Yoshikawa, Kurumi Taniguchi, Haruka Sawamura, Sae Morikawa, Moeka Nakashima, Tomoko Asai and Satoru Matsuda

Int. J. Mol. Sci. 2023, 24(6), 5742; https://0-doi-org.brum.beds.ac.uk/10.3390/ijms24065742 - 17 Mar 2023

Cited by 13 | Viewed by 5307

Abstract

The tryptophan and kynurenine pathway is well-known to play an important role in nervous, endocrine, and immune systems, as well as in the development of inflammatory diseases. It has been documented that some kynurenine metabolites are considered to have anti-oxidative, anti-inflammatory, and/or neuroprotective properties. Importantly, many of these kynurenine metabolites may possess immune-regulatory properties that could alleviate the inflammation response. The abnormal activation of the tryptophan and kynurenine pathway might be involved in the pathophysiological process of various immune-related diseases, such as inflammatory bowel disease, cardiovascular disease, osteoporosis, and/or polycystic ovary syndrome. Interestingly, kynurenine metabolites may be involved in the brain memory system and/or intricate immunity via the modulation of glial function. In the further deliberation of this concept with engram, the roles of gut microbiota could lead to the development of remarkable treatments for the prevention of and/or the therapeutics for various intractable immune-related diseases. Full article

(This article belongs to the Special Issue Amino Acid Metabolism: Design, Nutrition, and Disorders)

► Show Figures