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Park I, Nam H, Lee Y, Wickramasuriya SS, Smith AH, Rehberger TG, Lillehoj HS. The effect of gut microbiota-derived carnosine on mucosal integrity and immunity in broiler chickens challenged with Eimeria maxima. Poult Sci 2024; 103:103837. [PMID: 38848630 PMCID: PMC11214313 DOI: 10.1016/j.psj.2024.103837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2024] [Revised: 04/22/2024] [Accepted: 05/04/2024] [Indexed: 06/09/2024] Open
Abstract
In the first study, an in vitro culture system was developed to investigate the effects of carnosine on macrophage proinflammatory cytokine response using an established chicken macrophage cell line (CMC), gut integrity using a chicken intestinal epithelial cell line (IEC), muscle differentiation in quail muscle cells (QMCs) and primary chicken embryonic muscle cells (PMCs), and direct anti-parasitic effect against Eimeria maxima sporozoites. Cells to be tested were seeded in 24-well plates and treated with carnosine at 4 different concentrations (0.1, 1.0, and 10.0 µg). After 18 h of incubation, cells were harvested to measure gene expression of proinflammatory cytokines in CMC, tight junction (TJ) proteins in IECs, and muscle cell growth markers in QMCs and PMCs. In vivo trials were conducted to investigate the effect of dietary carnosine on disease parameters in broiler chickens challenged with E. maxima. One hundred and twenty male broiler chickens (0-day-old) were allocated into 4 treatment groups: 1) basal diet without infection (NC), 2) basal diet with E. maxima infection (PC), 3) carnosine at 10.0 mg/kg feed with PC (HCS), and 4) carnosine at 1.0 mg/kg feed with PC (LCS). All groups except NC were orally infected with E. maxima on d 14. Jejunal samples were collected for lesion scoring and jejunum gut tissues were used for transcriptomic analysis of cytokines and TJ proteins. In vitro, carnosine treatment significantly decreased IL-1β gene expression in CMC following LPS stimulation. In vivo feeding studies showed that dietary carnosine increased BW and ADG of chickens in E. maxima-infected groups and reduced the jejunal lesion score and fecal oocyst shedding in HCS group. Jejunal IL-1β, IL-8, and IFN-γ expression were suppressed in the HCS group compared to PC. The expression levels of claudin-1 and occludin in IECs were also increased in HCS following carnosine treatment. In conclusion, these findings highlight the beneficial effects of dietary carnosine supplementation on intestinal immune responses and gut barrier function in broiler chickens exposed to E. maxima infection.
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Affiliation(s)
- Inkyung Park
- Animal Bioscience and Biotechnology Laboratory, Beltsville Agricultural Research Center, Agricultural Research Service, USDA, MD 20705, USA
| | - Hyoyoun Nam
- Animal Bioscience and Biotechnology Laboratory, Beltsville Agricultural Research Center, Agricultural Research Service, USDA, MD 20705, USA
| | - Youngsub Lee
- Animal Bioscience and Biotechnology Laboratory, Beltsville Agricultural Research Center, Agricultural Research Service, USDA, MD 20705, USA
| | - Samiru S Wickramasuriya
- Animal Bioscience and Biotechnology Laboratory, Beltsville Agricultural Research Center, Agricultural Research Service, USDA, MD 20705, USA
| | | | | | - Hyun S Lillehoj
- Animal Bioscience and Biotechnology Laboratory, Beltsville Agricultural Research Center, Agricultural Research Service, USDA, MD 20705, USA.
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2
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Wilson JD, Dworsky-Fried M, Ismail N. Neurodevelopmental implications of COVID-19-induced gut microbiome dysbiosis in pregnant women. J Reprod Immunol 2024; 165:104300. [PMID: 39004033 DOI: 10.1016/j.jri.2024.104300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2024] [Revised: 06/25/2024] [Accepted: 07/10/2024] [Indexed: 07/16/2024]
Abstract
The global public health emergency of COVID-19 in January 2020 prompted a surge in research focusing on the pathogenesis and clinical manifestations of the virus. While numerous reports have been published on the acute effects of COVID-19 infection, the review explores the multifaceted long-term implications of COVID-19, with a particular focus on severe maternal COVID-19 infection, gut microbiome dysbiosis, and neurodevelopmental disorders in offspring. Severe COVID-19 infection has been associated with heightened immune system activation and gastrointestinal symptoms. Severe COVID-19 may also result in gut microbiome dysbiosis and a compromised intestinal mucosal barrier, often referred to as 'leaky gut'. Increased gut permeability facilitates the passage of inflammatory cytokines, originating from the inflamed intestinal mucosa and gut, into the bloodstream, thereby influencing fetal development during pregnancy and potentially elevating the risk of neurodevelopmental disorders such as autism and schizophrenia. The current review discusses the role of cytokine signaling molecules, microglia, and synaptic pruning, highlighting their potential involvement in the pathogenesis of neurodevelopmental disorders following maternal COVID-19 infection. Additionally, this review addresses the potential of probiotic interventions to mitigate gut dysbiosis and inflammatory responses associated with COVID-19, offering avenues for future research in optimizing maternal and fetal health outcomes.
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Affiliation(s)
- Jacob D Wilson
- NISE Laboratory, School of Psychology, Faculty of Social Science, University of Ottawa, Ottawa, Ontario K1N 9A4, Canada
| | - Michaela Dworsky-Fried
- NISE Laboratory, School of Psychology, Faculty of Social Science, University of Ottawa, Ottawa, Ontario K1N 9A4, Canada
| | - Nafissa Ismail
- NISE Laboratory, School of Psychology, Faculty of Social Science, University of Ottawa, Ottawa, Ontario K1N 9A4, Canada; LIFE Research Institute, Ottawa, Ontario K1N 6N5, Canada; University of Ottawa Brain and Mind Research Institute, Ottawa, Ontario K1H 8M5, Canada.
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3
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Delbreil P, Dhondt S, Kenaan El Rahbani RM, Banquy X, Mitchell JJ, Brambilla D. Current Advances and Material Innovations in the Search for Novel Treatments of Phenylketonuria. Adv Healthc Mater 2024:e2401353. [PMID: 38801163 DOI: 10.1002/adhm.202401353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2024] [Revised: 05/22/2024] [Indexed: 05/29/2024]
Abstract
Phenylketonuria (PKU) is a genetically inherited disease caused by a mutation of the gene encoding phenylalanine hydroxylase (PAH) and is the most common inborn error of amino acid metabolism. A deficiency of PAH leads to increased blood and brain levels of phenylalanine (Phe), which may cause permanent neurocognitive symptoms and developmental delays if untreated. Current management strategies for PKU consist of early detection through neonatal screening and implementation of a restrictive diet with minimal amounts of natural protein in combination with Phe-free supplements and low-protein foods to meet nutritional requirements. For milder forms of PKU, oral treatment with synthetic sapropterin (BH4), the cofactor of PAH, may improve metabolic control of Phe and allow for more natural protein to be included in the patient's diet. For more severe forms, daily injections of pegvaliase, a PEGylated variant of phenylalanine ammonia-lyase (PAL), may allow for normalization of blood Phe levels. However, the latter treatment has considerable drawbacks, notably a strong immunogenicity of the exogenous enzyme and the attached polymeric chains. Research for novel therapies of PKU makes use of innovative materials for drug delivery and state-of-the-art protein engineering techniques to develop treatments which are safer, more effective, and potentially permanent.
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Affiliation(s)
- Philippe Delbreil
- Faculty of Pharmacy, Université de Montréal, Québec, H3T 1J4, Canada
| | - Sofie Dhondt
- Faculty of Pharmacy, Université de Montréal, Québec, H3T 1J4, Canada
| | | | - Xavier Banquy
- Faculty of Pharmacy, Université de Montréal, Québec, H3T 1J4, Canada
| | - John J Mitchell
- Department of Pediatrics, Faculty of Medicine and Health Sciences, McGill University, Québec, H4A 3J1, Canada
| | - Davide Brambilla
- Faculty of Pharmacy, Université de Montréal, Québec, H3T 1J4, Canada
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4
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Yousef M, Rob M, Varghese S, Rao S, Zamir F, Paul P, Chaari A. The effect of microbiome therapy on COVID-19-induced gut dysbiosis: A narrative and systematic review. Life Sci 2024; 342:122535. [PMID: 38408636 DOI: 10.1016/j.lfs.2024.122535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 02/20/2024] [Accepted: 02/22/2024] [Indexed: 02/28/2024]
Abstract
AIMS Emerging evidence highlights the role of COVID-19 in instigating gut dysbiosis, with repercussions on disease severity and bidirectional gut-organ communication involving the lung, heart, brain, and liver. This study aims to evaluate the efficacy of probiotics, prebiotics, synbiotics, and fecal microbiota transplantation (FMT) in addressing gut dysbiosis associated with COVID-19, as well as their impact on related disease severity and clinical outcomes. MATERIALS AND METHODS We systematically review 27 studies exploring the efficacy of different microbiome-modulating therapies: probiotics, prebiotics, synbiotics, and fecal microbiota transplantation as potential interventions for COVID-19. KEY FINDINGS The probiotics and synbiotics investigated encompassed a spectrum of eight bacterial and fungal genera, namely Lactobacillus, Bifidobacterium, Streptococcus, Enterococcus, Pediococcus, Bacillus, Saccharomyces, and Kluyveromyces. Noteworthy prebiotics employed in these studies included chestnut tannin, galactooligosaccharides, fructooligosaccharides, xylooligosaccharide, and resistant dextrin. The majority of the investigated biotics exhibited positive effects on COVID-19 patients, manifesting in symptom alleviation, inflammation reduction, and notable decreases in mortality rates. Five studies reported death rates, showing an average mortality ranging from 0 % to 11 % in the intervention groups, as compared to 3 % to 30 % in the control groups. Specifically, probiotics, prebiotics, and synbiotics demonstrated efficacy in diminishing the duration and severity of symptoms while significantly accelerating viral and symptomatic remission. FMT emerged as a particularly effective strategy, successfully restoring gut microbiota and ameliorating gastrointestinal disorders. SIGNIFICANCE The insights gleaned from this review significantly contribute to our broader comprehension of the therapeutic potential of biotics in addressing COVID-19-related gut dysbiosis and mitigating secondary multi-organ complications.
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Affiliation(s)
- Mahmoud Yousef
- Weill Cornell Medicine-Qatar, Qatar Foundation-Education City, P.O. Box 24144, Doha, Qatar
| | - Mlaak Rob
- Weill Cornell Medicine-Qatar, Qatar Foundation-Education City, P.O. Box 24144, Doha, Qatar
| | - Sanish Varghese
- Weill Cornell Medicine-Qatar, Qatar Foundation-Education City, P.O. Box 24144, Doha, Qatar
| | - Shrinidhi Rao
- Weill Cornell Medicine-Qatar, Qatar Foundation-Education City, P.O. Box 24144, Doha, Qatar
| | - Fahad Zamir
- Weill Cornell Medicine-Qatar, Qatar Foundation-Education City, P.O. Box 24144, Doha, Qatar
| | - Pradipta Paul
- Weill Cornell Medicine-Qatar, Qatar Foundation-Education City, P.O. Box 24144, Doha, Qatar
| | - Ali Chaari
- Weill Cornell Medicine-Qatar, Qatar Foundation-Education City, P.O. Box 24144, Doha, Qatar.
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Liu J, Song J, Gao D, Li Y, Guo T, Yuan W, Chen M, Chen L, Zhang Y, Ma Q, Cui M, Song X, Wang R, Jiang J, Zou Z, Dong Y, Ma J. Exploring the associations between phthalate exposure and cardiometabolic risk factors clustering among children: The potential mediating role of insulin-resistant-related genes DNA methylation. JOURNAL OF HAZARDOUS MATERIALS 2024; 461:132578. [PMID: 37741207 DOI: 10.1016/j.jhazmat.2023.132578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 09/02/2023] [Accepted: 09/17/2023] [Indexed: 09/25/2023]
Abstract
The relationship between childhood phthalates (PAEs) exposure, DNA methylation, and cardiometabolic risk (CMR) factors is not well understood. Children were included from a longitudinal cohort 2018-2020 in Xiamen, China. A nest case-control study was additionally conducted, and methylation in lysyl oxidase-like 3 (LOXL3) and solute Carrier Family 6 Member 19 (SLC6A19) were measured. Generalized linear models were used to estimate the associations between PAEs exposure and CMR factors, and mediation analyses of DNA methylation were conducted. The longitudinal study included 835 children aged 7-11 years, and the nest case-control study included 120 cases and 120 controls. Exposure to higher PAEs was correlated with increased CMR scores at baseline (β = 0.299, 95 %CI = 0.114, 0.485) and the final visit (β = 0.202, 95 %CI = 0.008, 0.397). In nest case-control study, higher mono-n-butyl phthalate (MnBP) exposure was related with elevated triglycerides (TG) (β = 0.283, 95 %CI = 0.025, 0.540). A decrement of methylation of CpG 33.34 of LOXL3 was found in response to MnBP exposure (β = -0.014, 95 %CI = -0.027, -0.001). Furthermore, increased methylation of LOXL3_CpG 33.34 and SLC6A19_CpG 11.12 was related to reduced TG. De-methylation of LOXL3_CpG 33.34 and SLC6A19_CpG 11.12 could mediate MnBP-TG pathways. Childhood exposure to PAEs was associated with increased CMR scores, and mediation of PAE exposure on childhood cardiometabolic health by LOXL3 and SLC6A19 de-methylation was observed.
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Affiliation(s)
- Jieyu Liu
- Institute of Child and Adolescent Health, School of Public Health, Peking University, National Health Commission Key Laboratory of Reproductive Health, Beijing, China
| | - Jieyun Song
- Institute of Child and Adolescent Health, School of Public Health, Peking University, National Health Commission Key Laboratory of Reproductive Health, Beijing, China
| | - Di Gao
- Department of Obstetrics and Gynecology, Peking University First Hospital, Beijing, China
| | - Yanhui Li
- School of Nursing, Peking University, Beijing, China
| | - Tongjun Guo
- Institute of Child and Adolescent Health, School of Public Health, Peking University, National Health Commission Key Laboratory of Reproductive Health, Beijing, China
| | - Wen Yuan
- Institute of Child and Adolescent Health, School of Public Health, Peking University, National Health Commission Key Laboratory of Reproductive Health, Beijing, China
| | - Manman Chen
- Institute of Child and Adolescent Health, School of Public Health, Peking University, National Health Commission Key Laboratory of Reproductive Health, Beijing, China
| | - Li Chen
- Institute of Child and Adolescent Health, School of Public Health, Peking University, National Health Commission Key Laboratory of Reproductive Health, Beijing, China
| | - Yi Zhang
- Institute of Child and Adolescent Health, School of Public Health, Peking University, National Health Commission Key Laboratory of Reproductive Health, Beijing, China
| | - Qi Ma
- Institute of Child and Adolescent Health, School of Public Health, Peking University, National Health Commission Key Laboratory of Reproductive Health, Beijing, China
| | - Mengjie Cui
- Institute of Child and Adolescent Health, School of Public Health, Peking University, National Health Commission Key Laboratory of Reproductive Health, Beijing, China
| | - Xinli Song
- Institute of Child and Adolescent Health, School of Public Health, Peking University, National Health Commission Key Laboratory of Reproductive Health, Beijing, China
| | - Ruolin Wang
- Institute of Child and Adolescent Health, School of Public Health, Peking University, National Health Commission Key Laboratory of Reproductive Health, Beijing, China
| | - Jianuo Jiang
- Institute of Child and Adolescent Health, School of Public Health, Peking University, National Health Commission Key Laboratory of Reproductive Health, Beijing, China
| | - Zhiyong Zou
- Institute of Child and Adolescent Health, School of Public Health, Peking University, National Health Commission Key Laboratory of Reproductive Health, Beijing, China
| | - Yanhui Dong
- Institute of Child and Adolescent Health, School of Public Health, Peking University, National Health Commission Key Laboratory of Reproductive Health, Beijing, China.
| | - Jun Ma
- Institute of Child and Adolescent Health, School of Public Health, Peking University, National Health Commission Key Laboratory of Reproductive Health, Beijing, China.
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6
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Kukułowicz J, Pietrzak-Lichwa K, Klimończyk K, Idlin N, Bajda M. The SLC6A15-SLC6A20 Neutral Amino Acid Transporter Subfamily: Functions, Diseases, and Their Therapeutic Relevance. Pharmacol Rev 2023; 76:142-193. [PMID: 37940347 DOI: 10.1124/pharmrev.123.000886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 09/07/2023] [Accepted: 11/02/2023] [Indexed: 11/10/2023] Open
Abstract
The neutral amino acid transporter subfamily that consists of six members, consecutively SLC6A15-SLC620, also called orphan transporters, represents membrane, sodium-dependent symporter proteins that belong to the family of solute carrier 6 (SLC6). Primarily, they mediate the transport of neutral amino acids from the extracellular milieu toward cell or storage vesicles utilizing an electric membrane potential as the driving force. Orphan transporters are widely distributed throughout the body, covering many systems; for instance, the central nervous, renal, or intestinal system, supplying cells into molecules used in biochemical, signaling, and building pathways afterward. They are responsible for intestinal absorption and renal reabsorption of amino acids. In the central nervous system, orphan transporters constitute a significant medium for the provision of neurotransmitter precursors. Diseases related with aforementioned transporters highlight their significance; SLC6A19 mutations are associated with metabolic Hartnup disorder, whereas altered expression of SLC6A15 has been associated with a depression/stress-related disorders. Mutations of SLC6A18-SLCA20 cause iminoglycinuria and/or hyperglycinuria. SLC6A18-SLC6A20 to reach the cellular membrane require an ancillary unit ACE2 that is a molecular target for the spike protein of the SARS-CoV-2 virus. SLC6A19 has been proposed as a molecular target for the treatment of metabolic disorders resembling gastric surgery bypass. Inhibition of SLC6A15 appears to have a promising outcome in the treatment of psychiatric disorders. SLC6A19 and SLC6A20 have been suggested as potential targets in the treatment of COVID-19. In this review, we gathered recent advances on orphan transporters, their structure, functions, related disorders, and diseases, and in particular their relevance as therapeutic targets. SIGNIFICANCE STATEMENT: The following review systematizes current knowledge about the SLC6A15-SLCA20 neutral amino acid transporter subfamily and their therapeutic relevance in the treatment of different diseases.
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Affiliation(s)
- Jędrzej Kukułowicz
- Department of Physicochemical Drug Analysis, Faculty of Pharmacy, Jagiellonian University Medical College, Krakow, Poland
| | - Krzysztof Pietrzak-Lichwa
- Department of Physicochemical Drug Analysis, Faculty of Pharmacy, Jagiellonian University Medical College, Krakow, Poland
| | - Klaudia Klimończyk
- Department of Physicochemical Drug Analysis, Faculty of Pharmacy, Jagiellonian University Medical College, Krakow, Poland
| | - Nathalie Idlin
- Department of Physicochemical Drug Analysis, Faculty of Pharmacy, Jagiellonian University Medical College, Krakow, Poland
| | - Marek Bajda
- Department of Physicochemical Drug Analysis, Faculty of Pharmacy, Jagiellonian University Medical College, Krakow, Poland
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7
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Nydegger DT, Pujol-Giménez J, Kandasamy P, Vogt B, Hediger MA. Applications of the Microscale Thermophoresis Binding Assay in COVID-19 Research. Viruses 2023; 15:1432. [PMID: 37515120 PMCID: PMC10386446 DOI: 10.3390/v15071432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Revised: 06/16/2023] [Accepted: 06/21/2023] [Indexed: 07/30/2023] Open
Abstract
As the COVID-19 pandemic progresses, new variants of SARS-CoV-2 continue to emerge. This underscores the need to develop optimized tools to study such variants, along with new coronaviruses that may arise in the future. Such tools will also be instrumental in the development of new antiviral drugs. Here, we introduce microscale thermophoresis (MST) as a reliable and versatile tool for coronavirus research, which we demonstrate through three different applications described in this report: (1) binding of the SARS-CoV-2 spike receptor binding domain (RBD) to peptides as a strategy to prevent virus entry, (2) binding of the RBD to the viral receptor ACE2, and (3) binding of the RBD to ACE2 in complex with the amino acid transporter SLC6A20/SIT1 or its allelic variant rs61731475 (p.Ile529Val). Our results demonstrate that MST is a highly precise approach to studying protein-protein and/or protein-ligand interactions in coronavirus research, making it an ideal tool for studying viral variants and developing antiviral agents. Moreover, as shown in our results, a unique advantage of the MST assay over other available binding assays is the ability to measure interactions with membrane proteins in their near-native plasma membrane environment.
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Affiliation(s)
- Damian T Nydegger
- Department of Nephrology and Hypertension, Inselspital, University of Bern, Kinderklinik, Freiburgstrasse 15, 3010 Bern, Switzerland
- Department of Biomedical Research, Inselspital, University of Bern, Kinderklinik, Freiburgstrasse 15, 3010 Bern, Switzerland
| | - Jonai Pujol-Giménez
- Department of Nephrology and Hypertension, Inselspital, University of Bern, Kinderklinik, Freiburgstrasse 15, 3010 Bern, Switzerland
- Department of Biomedical Research, Inselspital, University of Bern, Kinderklinik, Freiburgstrasse 15, 3010 Bern, Switzerland
| | - Palanivel Kandasamy
- Department of Nephrology and Hypertension, Inselspital, University of Bern, Kinderklinik, Freiburgstrasse 15, 3010 Bern, Switzerland
- Department of Biomedical Research, Inselspital, University of Bern, Kinderklinik, Freiburgstrasse 15, 3010 Bern, Switzerland
| | - Bruno Vogt
- Department of Nephrology and Hypertension, Inselspital, University of Bern, Kinderklinik, Freiburgstrasse 15, 3010 Bern, Switzerland
- Department of Biomedical Research, Inselspital, University of Bern, Kinderklinik, Freiburgstrasse 15, 3010 Bern, Switzerland
| | - Matthias A Hediger
- Department of Nephrology and Hypertension, Inselspital, University of Bern, Kinderklinik, Freiburgstrasse 15, 3010 Bern, Switzerland
- Department of Biomedical Research, Inselspital, University of Bern, Kinderklinik, Freiburgstrasse 15, 3010 Bern, Switzerland
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8
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Wu G. Nutrition and Gut Health: Recent Advances and Implications for Development of Functional Foods. Int J Mol Sci 2023; 24:10075. [PMID: 37373221 DOI: 10.3390/ijms241210075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Accepted: 06/12/2023] [Indexed: 06/29/2023] Open
Abstract
The small intestine is a highly differentiated and complex organ with many nutritional, physiological, and immunological functions [...].
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Affiliation(s)
- Guoyao Wu
- Departments of Animal Science and Medical Physiology and Faculty of Nutrition, Texas A&M University, College Station, TX 77843, USA
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9
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Cuny H, Bozon K, Kirk RB, Sheng DZ, Bröer S, Dunwoodie SL. Maternal heterozygosity of Slc6a19 causes metabolic perturbation and congenital NAD deficiency disorder in mice. Dis Model Mech 2023; 16:282089. [PMID: 36374036 PMCID: PMC9702539 DOI: 10.1242/dmm.049647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Accepted: 10/06/2022] [Indexed: 11/16/2022] Open
Abstract
Nicotinamide adenine dinucleotide (NAD) is a key metabolite synthesised from vitamin B3 or tryptophan. Disruption of genes encoding NAD synthesis enzymes reduces NAD levels and causes congenital NAD deficiency disorder (CNDD), characterised by multiple congenital malformations. SLC6A19 (encoding B0AT1, a neutral amino acid transporter), represents the main transporter for free tryptophan in the intestine and kidney. Here, we tested whether Slc6a19 heterozygosity in mice limits the tryptophan available for NAD synthesis during pregnancy and causes adverse pregnancy outcomes. Pregnant Slc6a19+/- mice were fed diets depleted of vitamin B3, so that tryptophan was the source of NAD during gestation. This perturbed the NAD metabolome in pregnant Slc6a19+/- females, resulting in reduced NAD levels and increased rates of embryo loss. Surviving embryos were small and exhibited specific combinations of CNDD-associated malformations. Our results show that genes not directly involved in NAD synthesis can affect NAD metabolism and cause CNDD. They also suggest that human female carriers of a SLC6A19 loss-of-function allele might be susceptible to adverse pregnancy outcomes unless sufficient NAD precursor amounts are available during gestation. This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Hartmut Cuny
- Developmental and Stem Cell Biology Division, Victor Chang Cardiac Research Institute, Sydney, NSW 2010, Australia
- School of Clinical Medicine, Faculty of Medicine and Health, Sydney, NSW 2052, Australia
| | - Kayleigh Bozon
- Developmental and Stem Cell Biology Division, Victor Chang Cardiac Research Institute, Sydney, NSW 2010, Australia
| | - Rosemary B. Kirk
- Developmental and Stem Cell Biology Division, Victor Chang Cardiac Research Institute, Sydney, NSW 2010, Australia
| | - Delicia Z. Sheng
- Developmental and Stem Cell Biology Division, Victor Chang Cardiac Research Institute, Sydney, NSW 2010, Australia
| | - Stefan Bröer
- Research School of Biology, Australian National University, Canberra, ACT 0200, Australia
| | - Sally L. Dunwoodie
- Developmental and Stem Cell Biology Division, Victor Chang Cardiac Research Institute, Sydney, NSW 2010, Australia
- School of Clinical Medicine, Faculty of Medicine and Health, Sydney, NSW 2052, Australia
- Faculty of Science, University of New South Wales, Sydney, NSW 2052, Australia
- Author for correspondence ()
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10
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Kravetz Z, Rainald SK. New aspects for the brain in Hartnup disease based on mining of high-resolution cellular mRNA expression data for SLC6A19. IBRO Neurosci Rep 2023; 14:393-397. [PMID: 37101820 PMCID: PMC10123343 DOI: 10.1016/j.ibneur.2023.03.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2022] [Revised: 03/05/2023] [Accepted: 03/21/2023] [Indexed: 03/31/2023] Open
Abstract
Hartnup disease is an autosomal recessive, metabolic disorder caused by mutations of the neutral amino acid transporter, SLC6A19/B0AT1. Reduced absorption in the intestine and kidney results in deficiencies in neutral amino acids and their down-stream metabolites, including niacin, associated with skin lesions and neurological symptoms. The effects on the nervous system such as ataxia have been related to systemic deficiencies of tryptophan (and other neutral amino acids) as no expression of the B0AT1 transporter was found in the brain. In the intestine, SLC6A19 cooperates with ACE2 which has received major attention as the cellular receptor for SARS-CoV-2. When transcriptomics data for ACE2 and its partner proteins were examined, a previously unrecognized expression of Slc6a19 mRNA in the ependymal cells of the mouse brain was encountered that is set into the context of neurological manifestations of Hartnup disease with this communication. A novel role for SLC6A19/B0AT1 in amino acid transport from CSF into ependymal cells is proposed and a role of niacin in ependymal cells highlighted.
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11
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Navarro Garrido A, Kim YC, Oe Y, Zhang H, Crespo-Masip M, Goodluck HA, Kanoo S, Sanders PW, Bröer S, Vallon V. Aristolochic acid-induced nephropathy is attenuated in mice lacking the neutral amino acid transporter B 0AT1 ( Slc6a19). Am J Physiol Renal Physiol 2022; 323:F455-F467. [PMID: 35979966 PMCID: PMC9484999 DOI: 10.1152/ajprenal.00181.2022] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 07/29/2022] [Accepted: 08/10/2022] [Indexed: 01/10/2023] Open
Abstract
B0AT1 (Slc6a19) mediates absorption of neutral amino acids in the small intestine and in the kidneys, where it is primarily expressed in early proximal tubules (S1-S2). To determine the role of B0AT1 in nephropathy induced by aristolochic acid (AA), which targets the proximal tubule, littermate female B0AT1-deficient (Slc6a19-/-), heterozygous (Slc6a19+/-), and wild-type (WT) mice were administered AA (10 mg/kg ip) or vehicle every 3 days for 3 wk, and analyses were performed after the last injection or 3 wk later. Vehicle-treated mice lacking Slc6a19 showed normal body and kidney weight and plasma creatinine versus WT mice. The urinary glucose-to-creatinine ratio (UGCR) and urinary albumin-to-creatinine ratio (UACR) were two to four times higher in vehicle-treated Slc6a19-/- versus WT mice, associated with lesser expression of early proximal transporters Na+-glucose cotransporter 2 and megalin, respectively. AA caused tubular injury independently of B0AT1, including robust increases in cortical mRNA expression of p53, p21, and hepatitis A virus cellular receptor 1 (Havcr1), downregulation of related proximal tubule amino acid transporters B0AT2 (Slc6a15), B0AT3 (Slc6a18), and Slc7a9, and modest histological tubular damage and a rise in plasma creatinine. Absence of B0AT1, however, attenuated AA-induced cortical upregulation of mRNA markers of senescence (p16), inflammation [lipocalin 2 (Lcn2), C-C motif chemokine ligand 2 (Ccl2), and C-C motif chemokine receptor 2 (Ccr2)], and fibrosis [tissue inhibitor of metallopeptidase 1 (Timp1), transforming growth factor-β1 (Tgfb1), and collagen type I-α1 (Col1a1)], associated with lesser fibrosis staining, lesser suppression of proximal tubular organic anion transporter 1, restoration of Na+-glucose cotransporter 2 expression, and prevention of the AA-induced fivefold increase in the urinary albumin-to-creatinine ratio observed in WT mice. The data suggest that proximal tubular B0AT1 is important for the physiology of renal glucose and albumin retention but potentially deleterious for the kidney response following AA-induced kidney injury.NEW & NOTEWORTHY Based on insights from studies manipulating glucose transport, the hypothesis has been proposed that inhibiting intestinal uptake or renal reabsorption of energy substrates has unique therapeutic potential to improve metabolic disease and kidney outcome in response to injury. The present study takes this idea to B0AT1, the major transporter for neutral amino acids in the intestine and kidney, and shows that its absence attenuates aristolochic acid-induced nephropathy.
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Affiliation(s)
- Aleix Navarro Garrido
- Department of Medicine, University of California-San Diego, La Jolla, California
- Veterans Affairs San Diego Healthcare System, San Diego, California
| | - Young Chul Kim
- Department of Medicine, University of California-San Diego, La Jolla, California
- Veterans Affairs San Diego Healthcare System, San Diego, California
| | - Yuji Oe
- Department of Medicine, University of California-San Diego, La Jolla, California
- Veterans Affairs San Diego Healthcare System, San Diego, California
| | - Haiyan Zhang
- Department of Pathology, University of California-San Diego, San Diego, California
| | - Maria Crespo-Masip
- Department of Medicine, University of California-San Diego, La Jolla, California
- Veterans Affairs San Diego Healthcare System, San Diego, California
| | - Helen A Goodluck
- Department of Medicine, University of California-San Diego, La Jolla, California
- Veterans Affairs San Diego Healthcare System, San Diego, California
| | - Sadhana Kanoo
- Department of Medicine, University of California-San Diego, La Jolla, California
- Veterans Affairs San Diego Healthcare System, San Diego, California
| | - Paul W Sanders
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama
- Department of Veterans Affairs Medical Center, Birmingham, Alabama
| | - Stefan Bröer
- Research School of Biology, Australian National University, Canberra, ACT, Australia
| | - Volker Vallon
- Department of Medicine, University of California-San Diego, La Jolla, California
- Veterans Affairs San Diego Healthcare System, San Diego, California
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12
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Chiriaco M, Ursu GM, Amodio D, Cotugno N, Volpi S, Berardinelli F, Pizzi S, Cifaldi C, Zoccolillo M, Prigione I, Di Cesare S, Giancotta C, Anastasio E, Rivalta B, Pacillo L, Zangari P, Fiocchi AG, Diociaiuti A, Bruselles A, Pantaleoni F, Ciolfi A, D’Oria V, Palumbo G, Gattorno M, El Hachem M, de Villartay JP, Finocchi A, Palma P, Rossi P, Tartaglia M, Aiuti A, Antoccia A, Di Matteo G, Cancrini C. Radiosensitivity in patients affected by ARPC1B deficiency: a new disease trait? Front Immunol 2022; 13:919237. [PMID: 35967303 PMCID: PMC9372879 DOI: 10.3389/fimmu.2022.919237] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Accepted: 06/30/2022] [Indexed: 12/16/2022] Open
Abstract
Actin-related protein 2/3 complex subunit 1B (ARPC1B) deficiency is a recently described inborn error of immunity (IEI) presenting with combined immunodeficiency and characterized by recurrent infections and thrombocytopenia. Manifestations of immune dysregulation, including colitis, vasculitis, and severe dermatitis, associated with eosinophilia, hyper-IgA, and hyper-IgE are also described in ARPC1B-deficient patients. To date, hematopoietic stem cell transplantation seems to be the only curative option for patients. ARPC1B is part of the actin-related protein 2/3 complex (Arp2/3) and cooperates with the Wiskott–Aldrich syndrome protein (WASp) in the regulation of the actin cytoskeleton remodeling and in driving double-strand break clustering for homology-directed repair. In this study, we aimed to investigate radiosensitivity (RS) in ARPC1B-deficient patients to assess whether it can be considered an additional disease trait. First, we performed trio-based next-generation-sequencing studies to obtain the ARPC1B molecular diagnosis in our index case characterized by increased RS, and then we confirmed, using three different methods, an increment of radiosensitivity in all enrolled ARPC1B-deficient patients. In particular, higher levels of chromatid-type aberrations and γH2AX foci, with an increased number of cells arrested in the G2/M-phase of the cell cycle, were found in patients’ cells after ionizing radiation exposition and radiomimetic bleomycin treatment. Overall, our data suggest increased radiosensitivity as an additional trait in ARPC1B deficiency and support the necessity to investigate this feature in ARPC1B patients as well as in other IEI with cytoskeleton defects to address specific clinical follow-up and optimize therapeutic interventions.
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Affiliation(s)
- Maria Chiriaco
- Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy
| | - Giorgiana Madalina Ursu
- Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy
- Academic department of Pediatrics, Research Unit of Primary Immunodeficiencies, Bambino Gesù Children’s Hospital, Scientific Institute for Research and Healthcare (IRCCS), Rome, Italy
| | - Donato Amodio
- Academic Department of Pediatrics, Research Unit of Clinical Immunology and Vaccinology, Bambino Gesù Children’s Hospital, Rome, Italy
| | - Nicola Cotugno
- Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy
- Academic Department of Pediatrics, Research Unit of Clinical Immunology and Vaccinology, Bambino Gesù Children’s Hospital, Rome, Italy
| | - Stefano Volpi
- Center for Autoinflammatory Diseases and Immunodeficiencies, Scientific Institute for Research and Healthcare (IRCCS) Istituto Giannina Gaslini and University of Genoa, Genoa, Italy
| | - Francesco Berardinelli
- Laboratory of Neurodevelopment, Neurogenetics and Molecular Neurobiology, Scientific Institute for Research and Healthcare (IRCCS) Santa Lucia Foundation, Rome, Italy
- Department of Science, Roma Tre University, Rome, Italy
| | - Simone Pizzi
- Genetics and Rare Diseases Research Division, Bambino Gesù Children’s Hospital, Scientific Institute for Research and Healthcare (IRCCS), Rome, Italy
| | - Cristina Cifaldi
- Academic department of Pediatrics, Research Unit of Primary Immunodeficiencies, Bambino Gesù Children’s Hospital, Scientific Institute for Research and Healthcare (IRCCS), Rome, Italy
| | - Matteo Zoccolillo
- Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy
- San Raffaele Telethon Institute for Gene Therapy, Scientific Institute for Research and Healthcare (IRCCS), San Raffaele Scientific Institute, Milan, Italy
| | - Ignazia Prigione
- Center for Autoinflammatory Diseases and Immunodeficiencies, Scientific Institute for Research and Healthcare (IRCCS) Istituto Giannina Gaslini and University of Genoa, Genoa, Italy
| | - Silvia Di Cesare
- Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy
- Academic department of Pediatrics, Research Unit of Primary Immunodeficiencies, Bambino Gesù Children’s Hospital, Scientific Institute for Research and Healthcare (IRCCS), Rome, Italy
| | - Carmela Giancotta
- Academic Department of Pediatrics, Research Unit of Clinical Immunology and Vaccinology, Bambino Gesù Children’s Hospital, Rome, Italy
| | - Elisa Anastasio
- Department of Medical and Surgical Sciences, Pediatrics Unit, University “Magna Graecia”, Catanzaro, Italy
| | - Beatrice Rivalta
- Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy
- Academic department of Pediatrics, Research Unit of Primary Immunodeficiencies, Bambino Gesù Children’s Hospital, Scientific Institute for Research and Healthcare (IRCCS), Rome, Italy
| | - Lucia Pacillo
- Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy
- Academic department of Pediatrics, Research Unit of Primary Immunodeficiencies, Bambino Gesù Children’s Hospital, Scientific Institute for Research and Healthcare (IRCCS), Rome, Italy
| | - Paola Zangari
- Academic Department of Pediatrics, Research Unit of Clinical Immunology and Vaccinology, Bambino Gesù Children’s Hospital, Rome, Italy
| | - Alessandro G. Fiocchi
- Pediatric Allergology Unit, Bambino Gesù Children’s Hospital, Scientific Institute for Research and Healthcare (IRCCS), Rome, Italy
| | - Andrea Diociaiuti
- Dermatology Unit, Bambino Gesù Children’s Hospital, Scientific Institute for Research and Healthcare (IRCCS), Rome, Italy
| | - Alessandro Bruselles
- Department of Oncology and Molecular Medicine, Istituto Superiore di Sanità, Rome, Italy
| | - Francesca Pantaleoni
- Genetics and Rare Diseases Research Division, Bambino Gesù Children’s Hospital, Scientific Institute for Research and Healthcare (IRCCS), Rome, Italy
| | - Andrea Ciolfi
- Genetics and Rare Diseases Research Division, Bambino Gesù Children’s Hospital, Scientific Institute for Research and Healthcare (IRCCS), Rome, Italy
| | - Valentina D’Oria
- Research Laboratories, Bambino Gesù Children’s Hospital, Scientific Institute for Research and Healthcare (IRCCS), Rome, Italy
| | - Giuseppe Palumbo
- Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy
- Department of Haematology, Bambino Gesù Children’s Hospital, Scientific Institute for Research and Healthcare (IRCCS), Rome, Italy
| | - Marco Gattorno
- Center for Autoinflammatory Diseases and Immunodeficiencies, Scientific Institute for Research and Healthcare (IRCCS) Istituto Giannina Gaslini and University of Genoa, Genoa, Italy
| | - Maya El Hachem
- Dermatology Unit, Bambino Gesù Children’s Hospital, Scientific Institute for Research and Healthcare (IRCCS), Rome, Italy
| | - Jean-Pierre de Villartay
- Université de Paris, Imagine Institute, Laboratory “Genome Dynamics in the Immune System”, INSERM UMR 1163, F-75015, Paris, France
| | - Andrea Finocchi
- Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy
- Academic department of Pediatrics, Research Unit of Primary Immunodeficiencies, Bambino Gesù Children’s Hospital, Scientific Institute for Research and Healthcare (IRCCS), Rome, Italy
| | - Paolo Palma
- Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy
- Academic Department of Pediatrics, Research Unit of Clinical Immunology and Vaccinology, Bambino Gesù Children’s Hospital, Rome, Italy
| | - Paolo Rossi
- Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy
- Academic department of Pediatrics, Research Unit of Primary Immunodeficiencies, Bambino Gesù Children’s Hospital, Scientific Institute for Research and Healthcare (IRCCS), Rome, Italy
- Academic Department of Pediatrics, Research Unit of Clinical Immunology and Vaccinology, Bambino Gesù Children’s Hospital, Rome, Italy
| | - Marco Tartaglia
- Genetics and Rare Diseases Research Division, Bambino Gesù Children’s Hospital, Scientific Institute for Research and Healthcare (IRCCS), Rome, Italy
| | - Alessandro Aiuti
- San Raffaele Telethon Institute for Gene Therapy, Scientific Institute for Research and Healthcare (IRCCS), San Raffaele Scientific Institute, Milan, Italy
- Pediatric Immunohematology, San Raffaele Scientific Institute, Milan, Italy
- Vita Salute San Raffaele University, Milan, Italy
| | | | - Gigliola Di Matteo
- Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy
- Academic department of Pediatrics, Research Unit of Primary Immunodeficiencies, Bambino Gesù Children’s Hospital, Scientific Institute for Research and Healthcare (IRCCS), Rome, Italy
- *Correspondence: Gigliola Di Matteo, ; Caterina Cancrini, ;
| | - Caterina Cancrini
- Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy
- Academic department of Pediatrics, Research Unit of Primary Immunodeficiencies, Bambino Gesù Children’s Hospital, Scientific Institute for Research and Healthcare (IRCCS), Rome, Italy
- *Correspondence: Gigliola Di Matteo, ; Caterina Cancrini, ;
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13
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Bhutia YD, Mathew M, Sivaprakasam S, Ramachandran S, Ganapathy V. Unconventional Functions of Amino Acid Transporters: Role in Macropinocytosis (SLC38A5/SLC38A3) and Diet-Induced Obesity/Metabolic Syndrome (SLC6A19/SLC6A14/SLC6A6). Biomolecules 2022; 12:biom12020235. [PMID: 35204736 PMCID: PMC8961558 DOI: 10.3390/biom12020235] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Revised: 01/24/2022] [Accepted: 01/27/2022] [Indexed: 02/06/2023] Open
Abstract
Amino acid transporters are expressed in mammalian cells not only in the plasma membrane but also in intracellular membranes. The conventional function of these transporters is to transfer their amino acid substrates across the lipid bilayer; the direction of the transfer is dictated by the combined gradients for the amino acid substrates and the co-transported ions (Na+, H+, K+ or Cl−) across the membrane. In cases of electrogenic transporters, the membrane potential also contributes to the direction of the amino acid transfer. In addition to this expected traditional function, several unconventional functions are known for some of these amino acid transporters. This includes their role in intracellular signaling, regulation of acid–base balance, and entry of viruses into cells. Such functions expand the biological roles of these transporters beyond the logical amino acid homeostasis. In recent years, two additional unconventional biochemical/metabolic processes regulated by certain amino acid transporters have come to be recognized: macropinocytosis and obesity. This adds to the repertoire of biological processes that are controlled and regulated by amino acid transporters in health and disease. In the present review, we highlight the unusual involvement of selective amino acid transporters in macropinocytosis (SLC38A5/SLC38A3) and diet-induced obesity/metabolic syndrome (SLC6A19/SLC6A14/SLC6A6).
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14
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Duanmu Q, Tan B, Wang J, Huang B, Li J, Kang M, Huang K, Deng Q, Yin Y. The Amino Acids Sensing and Utilization in Response to Dietary Aromatic Amino Acid Supplementation in LPS-Induced Inflammation Piglet Model. Front Nutr 2022; 8:819835. [PMID: 35111801 PMCID: PMC8801454 DOI: 10.3389/fnut.2021.819835] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Accepted: 12/16/2021] [Indexed: 12/19/2022] Open
Abstract
Dietary supplementation with aromatic amino acids (AAAs) has been demonstrated to alleviate intestinal inflammation induced by lipopolysaccharide (LPS) in the piglets. But the mechanism of AAA sensing and utilization under inflammatory conditions is not well-understood. The study was conducted with 32 weanling piglets using a 2 × 2 factorial arrangement (diet and LPS challenge) in a randomized complete block design. Piglets were fed as basal diet or the basal diet supplemented with 0.16% tryptophan (Trp), 0.41% phenylalanine (Phe), and 0.22% tyrosine (Tyr) for 21 days. The results showed that LPS treatment significantly reduced the concentrations of cholecystokinin (CCK) and total protein but increased leptin concentration, the activities of alanine transaminase, and aspartate aminotransferase in serum. Dietary supplementation with AAAs significantly increased the serum concentrations of CCK, peptide YY (PYY), and total protein but decreased the blood urea nitrogen. LPS challenge reduced the ileal threonine (Thr) digestibility, as well as serum isoleucine (Ile) and Trp concentrations, but increased the serum concentrations of Phe, Thr, histidine (His), alanine (Ala), cysteine (Cys), and serine (Ser) (P < 0.05). The serum-free amino acid concentrations of His, lysine (Lys), arginine (Arg), Trp, Tyr, Cys, and the digestibilities of His, Lys, Arg, and Cys were significantly increased by feeding AAA diets (P < 0.05). Dietary AAA supplementation significantly increased the serum concentrations of Trp in LPS-challenged piglets (P < 0.05). In the jejunal mucosa, LPS increased the contents of Ala and Cys, and the mRNA expressions of solute carrier (SLC) transporters (i.e., SLC7A11, SLC16A10, SLC38A2, and SLC3A2), but decreased Lys and glutamine (Gln) contents, and SLC1A1 mRNA expression (P < 0.05). In the ileal mucosa, LPS challenge induced increasing in SLC7A11 and SLC38A2 and decreasing in SLC38A9 and SLC36A1 mRNA expressions, AAAs supplementation significantly decreased mucosal amino acid (AA) concentrations of methionine (Met), Arg, Ala, and Tyr, etc. (P < 0.05). And the interaction between AAAs supplementation and LPS challenge significantly altered the expressions of SLC36A1 and SLC38A9 mRNA (P < 0.05). Together, these findings indicated that AAAs supplementation promoted the AAs absorption and utilization in the small intestine of piglets and increased the mRNA expressions of SLC transports to meet the high demands for specific AAs in response to inflammation and immune response.
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Affiliation(s)
- Qing Duanmu
- College of Animal Science and Technology, Hunan Agricultural University, Changsha, China
| | - Bie Tan
- College of Animal Science and Technology, Hunan Agricultural University, Changsha, China
- Laboratory of Animal Nutritional Physiology and Metabolic Process, Key Laboratory of Agro-Ecological Processes in Subtropical Region, National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, China
| | - Jing Wang
- College of Animal Science and Technology, Hunan Agricultural University, Changsha, China
| | - Bo Huang
- College of Animal Science and Technology, Hunan Agricultural University, Changsha, China
- Laboratory of Animal Nutritional Physiology and Metabolic Process, Key Laboratory of Agro-Ecological Processes in Subtropical Region, National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, China
| | - Jianjun Li
- Laboratory of Animal Nutritional Physiology and Metabolic Process, Key Laboratory of Agro-Ecological Processes in Subtropical Region, National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, China
| | - Meng Kang
- College of Animal Science and Technology, Hunan Agricultural University, Changsha, China
| | - Ke Huang
- College of Animal Science and Technology, Hunan Agricultural University, Changsha, China
| | - Qiuchun Deng
- College of Animal Science and Technology, Hunan Agricultural University, Changsha, China
| | - Yulong Yin
- College of Animal Science and Technology, Hunan Agricultural University, Changsha, China
- Laboratory of Animal Nutritional Physiology and Metabolic Process, Key Laboratory of Agro-Ecological Processes in Subtropical Region, National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, China
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15
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Sen A. Deficient synthesis of melatonin in COVID-19 can impair the resistance of coronavirus patients to mucormycosis. Med Hypotheses 2021; 158:110722. [PMID: 34753008 PMCID: PMC8553412 DOI: 10.1016/j.mehy.2021.110722] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 10/12/2021] [Accepted: 10/17/2021] [Indexed: 12/25/2022]
Abstract
In addition to uncontrolled diabetes and the excess use of corticosteroids, it is believed that other factors may be responsible for the recent spurt of COVID-19 associated mucormycosis (CAM). In the present paper it is argued that COVID-19 increases the susceptibility of the patients to mucormycosis by augmenting the virulence factors of the mucor species, where deficient synthesis of melatonin plays a key role. Melatonin is synthesized from tryptophan via the serotonin pathway and melatonin deficiency in COVID-19 arises from the faulty absorption of tryptophan from the food because SARS-CoV-2 downregulates angiotensin-converting enzyme-2, the chaperone of the transporter of tryptophan. The enhanced fungal virulence in COVID-19 can be mitigated by correcting the melatonin deficiency as melatonin can prevent iron acquisition of the mucor species and inhibit their morphological transition from the yeast to the virulent hyphal form, given the fact that melatonin is an iron chelator, calmodulin blocker and inhibitor of myeloperoxidase as well as inhibitor of ferroptosis and pyroptosis. Also, by lowering the expression of glucose-regulated protein 78 and by inhibiting the suppression of T-cell immunity, melatonin can further increase the resistance of the patients to mucormycosis. Accordingly, clinical trials should be carried out on tryptophan supplementation, administration of selective serotonin reuptake inhibitors (to increase serotonin, the precursor of melatonin), and exogenous melatonin to find out how they perform in eliminating or reducing the propensity of the coronavirus patients to CAM.
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Affiliation(s)
- Amarnath Sen
- 40 Jadunath Sarbovouma Lane, Kolkata 700035, India.
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16
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Guo Y, Wang B, Gao H, Gao L, Hua R, Xu JD. ACE2 in the Gut: The Center of the 2019-nCoV Infected Pathology. Front Mol Biosci 2021; 8:708336. [PMID: 34631794 PMCID: PMC8493804 DOI: 10.3389/fmolb.2021.708336] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Accepted: 08/11/2021] [Indexed: 12/25/2022] Open
Abstract
The 2019-nCoV is a rapidly contagious pneumonia caused by the recently discovered coronavirus. Although generally the most noticeable symptoms are concentrated in the lungs, the disorders in the gastrointestinal tract are of great importance in the diagnosis of 2019-nCoV. The angiotensin-converting enzyme 2 (ACE2), an important regulator of many physiological functions, including blood pressure and nutrients absorption, is recently identified as a vital entry for 2019-nCoV to enter host cells. In this review, we summarize its functions both physiologically and pathologically. We also elaborate its conflicting roles from the clews of contemporary researches, which may provide significant indications for pharmacological investigations and clinical uses.
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Affiliation(s)
- Yuexin Guo
- Department of Oral Medicine "5+3" Program, Basic Medical College, Capital Medical University, Beijing, China
| | - Boya Wang
- Undergraduate Student of 2018 Eight Program of Clinical Medicine, Peking University Health Science Center, Beijing, China
| | - Han Gao
- Department of Physiology and Pathophysiology, Basic Medical College, Capital Medical University, Beijing, China
| | - Lei Gao
- Department of Bioinformatics, School of Biomedical Engineering, Capital Medical University, Beijing, China
| | - Rongxuan Hua
- Department of Clinical Medicine "5+3" Program, Basic Medical College, Capital Medical University, Beijing, China
| | - Jing-Dong Xu
- Department of Physiology and Pathophysiology, Basic Medical College, Capital Medical University, Beijing, China
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17
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Neuropsychiatric Ramifications of COVID-19: Short-Chain Fatty Acid Deficiency and Disturbance of Microbiota-Gut-Brain Axis Signaling. BIOMED RESEARCH INTERNATIONAL 2021; 2021:7880448. [PMID: 34651049 PMCID: PMC8510788 DOI: 10.1155/2021/7880448] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Accepted: 09/07/2021] [Indexed: 02/08/2023]
Abstract
COVID-19-associated neuropsychiatric complications are soaring. There is an urgent need to understand the link between COVID-19 and neuropsychiatric disorders. To that end, this article addresses the premise that SARS-CoV-2 infection results in gut dysbiosis and an altered microbiota-gut-brain (MGB) axis that in turn contributes to the neuropsychiatric ramifications of COVID-19. Altered MGB axis activity has been implicated independently as a risk of neuropsychiatric disorders. A review of the changes in gut microbiota composition in individual psychiatric and neurological disorders and gut microbiota in COVID-19 patients revealed a shared "microbial signature" characterized by a lower microbial diversity and richness and a decrease in health-promoting anti-inflammatory commensal bacteria accompanied by an increase in opportunistic proinflammatory pathogens. Notably, there was a decrease in short-chain fatty acid (SCFA) producing bacteria. SCFAs are key bioactive microbial metabolites with anti-inflammatory functions and have been recognized as a critical signaling pathway in the MGB axis. SCFA deficiency is associated with brain inflammation, considered a cardinal feature of neuropsychiatric disorders. The link between SARS-CoV-2 infection, gut dysbiosis, and altered MGB axis is further supported by COVID-19-associated gastrointestinal symptoms, a high number of SARS-CoV-2 receptors, angiotensin-cleaving enzyme-2 (ACE-2) in the gut, and viral presence in the fecal matter. The binding of SARS-CoV-2 to the receptor results in ACE-2 deficiency that leads to decreased transport of vital dietary components, gut dysbiosis, proinflammatory gut status, increased permeability of the gut-blood barrier (GBB), and systemic inflammation. More clinical research is needed to substantiate further the linkages described above and evaluate the potential significance of gut microbiota as a diagnostic tool. Meanwhile, it is prudent to propose changes in dietary recommendations in favor of a high fiber diet or supplementation with SCFAs or probiotics to prevent or alleviate the neuropsychiatric ramifications of COVID-19.
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18
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Sajdel-Sulkowska EM. A Dual-Route Perspective of SARS-CoV-2 Infection: Lung- vs. Gut-specific Effects of ACE-2 Deficiency. Front Pharmacol 2021; 12:684610. [PMID: 34177593 PMCID: PMC8226136 DOI: 10.3389/fphar.2021.684610] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 05/21/2021] [Indexed: 12/11/2022] Open
Abstract
SARS-CoV-2, primarily considered a respiratory virus, is increasingly recognized as having gastrointestinal aspects based on its presence in the gastrointestinal (GI) tract and feces. SARS-CoV-2 uses as a receptor angiotensin-converting enzyme 2 (ACE-2), a critical member of the renin-angiotensin-aldosterone system (RAAS) involved in the regulation of blood pressure and fluid system. In addition to the systemic endocrine functions, RAAS components are also involved in intracrine and organ-specific local functions. The angiotensin-converting enzyme 2 (ACE-2) is a key component of RAAS and a receptor for SARS-CoV-2. It is expressed in many tissues with gastrointestinal (GI) tract ACE-2 levels far exceeding those in the respiratory tract. SARS-CoV-2 binding to its receptor results in a deficiency of ACE-2 activity in endocrine, intracrine, and local lung and GI tract ACE-2. The local ACE-2 has different organ-specific functions, including hypertension-independent activities; dysregulations of these functions may contribute to multiorgan COVID-19 pathology, its severity, long-term effects, and mortality. We review supporting evidence from this standpoint. Notably, COVID-19 comorbidities involving hypertension, obesity, heart disease, kidney disease, and diabetes are associated with gastrointestinal problems and display ACE-2 deficits. While RAAS inhibitors target both endocrine and intracrine ACE-2 activity, the deficit of the local ACE-2 activity in the lungs and more so in the gut have not been targeted. Consequently, the therapeutic approach to COVID-19 should be carefully reconsidered. Ongoing clinical trials testing oral probiotic bound ACE-2 delivery are promising.
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19
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Sen A. Does serotonin deficiency lead to anosmia, ageusia, dysfunctional chemesthesis and increased severity of illness in COVID-19? Med Hypotheses 2021; 153:110627. [PMID: 34139598 PMCID: PMC8180092 DOI: 10.1016/j.mehy.2021.110627] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Revised: 05/24/2021] [Accepted: 06/04/2021] [Indexed: 12/20/2022]
Abstract
Different mechanisms forwarded to understand anosmia and ageusia in coronavirus patients are not adequate to explain reversible anosmia and ageusia, which are resolved quickly. In addition, the reason behind the impaired chemesthetic sensations in some coronavirus patients remains unknown. In the present paper it is proposed that SARS-CoV-2 patients suffer from depletion of tryptophan, as ACE2, a key element in the process of absorption of tryptophan from the food, is significantly reduced in the patients as coronavirus uses ACE2 as the receptor to enter the host cells. The tryptophan depletion leads to a deficit of serotonin (5-HT) in SARS-COV-2 patients because tryptophan is the precursor in the synthesis of 5-HT. Such 5-HT deficiency can explain anosmia, ageusia and dysfunctional chemesthesis in COVID-19, given the fact that 5-HT is an important neuromodulator in the olfactory neurons, taste receptor cells and transient receptor potential channels (TRP channels) involved in chemesthesis. In addition, 5-HT deficiency worsens silent hypoxemia and depresses hypoxic pulmonary vasoconstriction leading to increased severity of the disease. Also, the levels of anti-inflammatory melatonin (synthesized from 5-HT) and nicotinamide adenine dinucleotide (NAD+, produced from niacin whose precursor is the tryptophan) might decrease in coronavirus patients resulting in the aggravation of the disease. Interestingly, selective serotonin reuptake inhibitors (SSRIs) may not be of much help in correcting the 5-HT deficiency in COVID-19 patients, as their efficacy goes down significantly when there is depletion of tryptophan in the system. Hence, tryptophan supplementation may herald a radical change in the treatment of COVID-19 and accordingly, clinical trials (therapeutic / prophylactic) should be conducted on coronavirus patients to find out how tryptophan supplementation (oral or parenteral, the latter in severe cases where there is hardly any absorption of tryptophan from the food) helps in curing, relieving or preventing the olfactory, gustatory and chemesthetic dysfunctions and in lessening the severity of the disease.
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Affiliation(s)
- Amarnath Sen
- 40 Jadunath Sarbovouma Lane, Kolkata 700035, India.
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20
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Gerbeth-Kreul C, Pommereau A, Ruf S, Kane JL, Kuntzweiler T, Hessler G, Engel CK, Shum P, Wei L, Czech J, Licher T. A Solid Supported Membrane-Based Technology for Electrophysical Screening of B 0AT1-Modulating Compounds. SLAS DISCOVERY 2021; 26:783-797. [PMID: 33955247 DOI: 10.1177/24725552211011180] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Classical high-throughput screening (HTS) technologies for the analysis of ionic currents across biological membranes can be performed using fluorescence-based, radioactive, and mass spectrometry (MS)-based uptake assays. These assays provide rapid results for pharmacological HTS, but the underlying, indirect analytical character of these assays can be linked to high false-positive hit rates. Thus, orthogonal and secondary assays using more biological target-based technologies are indispensable for further compound validation and optimization. Direct assay technologies for transporter proteins are electrophysiology-based, but are also complex, time-consuming, and not well applicable for automated profiling purposes. In contrast to conventional patch clamp systems, solid supported membrane (SSM)-based electrophysiology is a sensitive, membrane-based method for transporter analysis, and current technical developments target the demand for automated, accelerated, and sensitive assays for transporter-directed compound screening. In this study, the suitability of the SSM-based technique for pharmacological compound identification and optimization was evaluated performing cell-free SSM-based measurements with the electrogenic amino acid transporter B0AT1 (SLC6A19). Electrophysiological characterization of leucine-induced currents demonstrated that the observed signals were specific to B0AT1. Moreover, B0AT1-dependent responses were successfully inhibited using an established in-house tool compound. Evaluation of current stability and data reproducibility verified the robustness and reliability of the applied assay. Active compounds from primary screens of large compound libraries were validated, and false-positive hits were identified. These results clearly demonstrate the suitability of the SSM-based technique as a direct electrophysiological method for rapid and automated identification of small molecules that can inhibit B0AT1 activity.
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Affiliation(s)
- Carolin Gerbeth-Kreul
- In Vitro Biology & High-throughput Chemistry, Integrated Drug Discovery, Sanofi-Aventis Deutschland GmbH, Frankfurt, Germany
| | - Antje Pommereau
- In Vitro Biology & High-throughput Chemistry, Integrated Drug Discovery, Sanofi-Aventis Deutschland GmbH, Frankfurt, Germany
| | - Sven Ruf
- Synthetic Molecular Design, Integrated Drug Discovery, Sanofi-Aventis Deutschland GmbH, Frankfurt, Germany
| | - John L Kane
- Medicinal Chemistry, Integrated Drug Discovery, Sanofi-Genzyme, Waltham, MA, USA
| | - Theresa Kuntzweiler
- In Vitro Biology, Integrated Drug Discovery, Sanofi-Genzyme, Waltham, MA, USA
| | - Gerhard Hessler
- Synthetic Molecular Design, Integrated Drug Discovery, Sanofi-Aventis Deutschland GmbH, Frankfurt, Germany
| | - Christian K Engel
- Synthetic Molecular Design, Integrated Drug Discovery, Sanofi-Aventis Deutschland GmbH, Frankfurt, Germany
| | - Patrick Shum
- Medicinal Chemistry, Integrated Drug Discovery, Sanofi-Genzyme, Waltham, MA, USA
| | - LinLi Wei
- Medicinal Chemistry, Integrated Drug Discovery, Sanofi-Genzyme, Waltham, MA, USA
| | - Joerg Czech
- In Vitro Biology & High-throughput Chemistry, Integrated Drug Discovery, Sanofi-Aventis Deutschland GmbH, Frankfurt, Germany
| | - Thomas Licher
- In Vitro Biology & High-throughput Chemistry, Integrated Drug Discovery, Sanofi-Aventis Deutschland GmbH, Frankfurt, Germany
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21
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Cahill T, da Silveira WA, Renaud L, Williamson T, Wang H, Chung D, Overton I, Chan SSL, Hardiman G. Induced Torpor as a Countermeasure for Low Dose Radiation Exposure in a Zebrafish Model. Cells 2021; 10:906. [PMID: 33920039 PMCID: PMC8071006 DOI: 10.3390/cells10040906] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 04/07/2021] [Accepted: 04/11/2021] [Indexed: 12/15/2022] Open
Abstract
The development of the Artemis programme with the goal of returning to the moon is spurring technology advances that will eventually take humans to Mars and herald a new era of interplanetary space travel. However, long-term space travel poses unique challenges including exposure to ionising radiation from galactic cosmic rays and potential solar particle events, exposure to microgravity and specific nutritional challenges arising from earth independent exploration. Ionising radiation is one of the major obstacles facing future space travel as it can generate oxidative stress and directly damage cellular structures such as DNA, in turn causing genomic instability, telomere shortening, extracellular-matrix remodelling and persistent inflammation. In the gastrointestinal tract (GIT) this can lead to leaky gut syndrome, perforations and motility issues, which impact GIT functionality and affect nutritional status. While current countermeasures such as shielding from the spacecraft can attenuate harmful biological effects, they produce harmful secondary particles that contribute to radiation exposure. We hypothesised that induction of a torpor-like state would confer a radioprotective effect given the evidence that hibernation extends survival times in irradiated squirrels compared to active controls. To test this hypothesis, a torpor-like state was induced in zebrafish using melatonin treatment and reduced temperature, and radiation exposure was administered twice over the course of 10 days. The protective effects of induced-torpor were assessed via RNA sequencing and qPCR of mRNA extracted from the GIT. Pathway and network analysis were performed on the transcriptomic data to characterise the genomic signatures in radiation, torpor and torpor + radiation groups. Phenotypic analyses revealed that melatonin and reduced temperature successfully induced a torpor-like state in zebrafish as shown by decreased metabolism and activity levels. Genomic analyses indicated that low dose radiation caused DNA damage and oxidative stress triggering a stress response, including steroidal signalling and changes to metabolism, and cell cycle arrest. Torpor attenuated the stress response through an increase in pro-survival signals, reduced oxidative stress via the oxygen effect and detection and removal of misfolded proteins. This proof-of-concept model provides compelling initial evidence for utilizing an induced torpor-like state as a potential countermeasure for radiation exposure.
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Affiliation(s)
- Thomas Cahill
- School of Biological Sciences & Institute for Global Food Security, Queens University Belfast, Belfast BT9 5DL, UK; (T.C.); (W.A.d.S.); (H.W.)
| | - Willian Abraham da Silveira
- School of Biological Sciences & Institute for Global Food Security, Queens University Belfast, Belfast BT9 5DL, UK; (T.C.); (W.A.d.S.); (H.W.)
| | - Ludivine Renaud
- Department of Medicine, Medical University of South Carolina, Charleston, SC 29425, USA;
| | - Tucker Williamson
- Department of Drug Discovery and Biomedical Sciences, Medical University of South Carolina, Charleston, SC 29425, USA; (T.W.); (S.S.L.C.)
| | - Hao Wang
- School of Biological Sciences & Institute for Global Food Security, Queens University Belfast, Belfast BT9 5DL, UK; (T.C.); (W.A.d.S.); (H.W.)
| | - Dongjun Chung
- Department of Biomedical Informatics, The Ohio State University, Columbus, OH 43210, USA;
| | - Ian Overton
- Patrick G Johnston Centre for Cancer Research, Queen’s University Belfast, Belfast BT9 7AE, UK;
| | - Sherine S. L. Chan
- Department of Drug Discovery and Biomedical Sciences, Medical University of South Carolina, Charleston, SC 29425, USA; (T.W.); (S.S.L.C.)
| | - Gary Hardiman
- School of Biological Sciences & Institute for Global Food Security, Queens University Belfast, Belfast BT9 5DL, UK; (T.C.); (W.A.d.S.); (H.W.)
- Department of Medicine, Medical University of South Carolina, Charleston, SC 29425, USA;
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22
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Yang C, Xiao SY. COVID-19 and inflammatory bowel disease: A pathophysiological assessment. Biomed Pharmacother 2021; 135:111233. [PMID: 33433350 PMCID: PMC7834878 DOI: 10.1016/j.biopha.2021.111233] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Revised: 12/26/2020] [Accepted: 12/31/2020] [Indexed: 01/08/2023] Open
Abstract
Coronavirus disease-2019 (COVID-19), caused by SARS-CoV-2, has led to the ongoing global pandemic. Although most patients experience no or only mild symptoms, some patients can develop severe illness, such as progressive pneumonia, acute respiratory distress syndrome, secondary hemophagocytic lymphohistiocytosis and multiple organ failure caused by cytokine release syndrome. A majority of COVID-19 patients also develop gastrointestinal symptoms. These can present special challenges to the management of patients with inflammatory bowel disease (IBD) due to potential interactions between the immune response related to SARS-CoV-2 infection and dysregulated immunity associated with IBD. In this context, the pathogenesis of COVID-19 is reviewed in order to address these questions regarding immune interactions between COVID-19 and IBD.
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Affiliation(s)
- Chunxiu Yang
- Department of Pathology, Zhongnan Hospital of Wuhan University, Wuhan, China; Wuhan University Center for Pathology and Molecular Diagnostics, Wuhan, China
| | - Shu-Yuan Xiao
- Department of Pathology, Zhongnan Hospital of Wuhan University, Wuhan, China; Wuhan University Center for Pathology and Molecular Diagnostics, Wuhan, China; Department of Pathology, University of Chicago Medicine, Chicago, IL, United States.
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23
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Focht D, Neumann C, Lyons J, Eguskiza Bilbao A, Blunck R, Malinauskaite L, Schwarz IO, Javitch JA, Quick M, Nissen P. A non-helical region in transmembrane helix 6 of hydrophobic amino acid transporter MhsT mediates substrate recognition. EMBO J 2021; 40:e105164. [PMID: 33155685 PMCID: PMC7780149 DOI: 10.15252/embj.2020105164] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 09/23/2020] [Accepted: 10/01/2020] [Indexed: 12/30/2022] Open
Abstract
MhsT of Bacillus halodurans is a transporter of hydrophobic amino acids and a homologue of the eukaryotic SLC6 family of Na+ -dependent symporters for amino acids, neurotransmitters, osmolytes, or creatine. The broad range of transported amino acids by MhsT prompted the investigation of the substrate recognition mechanism. Here, we report six new substrate-bound structures of MhsT, which, in conjunction with functional studies, reveal how the flexibility of a Gly-Met-Gly (GMG) motif in the unwound region of transmembrane segment 6 (TM6) is central for the recognition of substrates of different size by tailoring the binding site shape and volume. MhsT mutants, harboring substitutions within the unwound GMG loop and substrate binding pocket that mimick the binding sites of eukaryotic SLC6A18/B0AT3 and SLC6A19/B0AT1 transporters of neutral amino acids, exhibited impaired transport of aromatic amino acids that require a large binding site volume. Conservation of a general (G/A/C)ΦG motif among eukaryotic members of SLC6 family suggests a role for this loop in a common mechanism for substrate recognition and translocation by SLC6 transporters of broad substrate specificity.
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Affiliation(s)
- Dorota Focht
- Department of Molecular Biology and GeneticsDanish Research Institute of Translational Neuroscience—DANDRITENordic‐EMBL Partnership for Molecular MedicineAarhus UniversityAarhus CDenmark
| | - Caroline Neumann
- Department of Molecular Biology and GeneticsDanish Research Institute of Translational Neuroscience—DANDRITENordic‐EMBL Partnership for Molecular MedicineAarhus UniversityAarhus CDenmark
| | - Joseph Lyons
- Department of Molecular Biology and GeneticsDanish Research Institute of Translational Neuroscience—DANDRITENordic‐EMBL Partnership for Molecular MedicineAarhus UniversityAarhus CDenmark
| | - Ander Eguskiza Bilbao
- Department of Molecular Biology and GeneticsDanish Research Institute of Translational Neuroscience—DANDRITENordic‐EMBL Partnership for Molecular MedicineAarhus UniversityAarhus CDenmark
| | - Rickard Blunck
- Department of PhysicsUniversité de MontréalMontréalQCCanada
| | - Lina Malinauskaite
- Department of Molecular Biology and GeneticsDanish Research Institute of Translational Neuroscience—DANDRITENordic‐EMBL Partnership for Molecular MedicineAarhus UniversityAarhus CDenmark
- MRC Laboratory of Molecular BiologyCambridgeUK
| | - Ilona O Schwarz
- Department of PsychiatryColumbia University Vagelos College of Physicians and SurgeonsNew YorkNYUSA
| | - Jonathan A Javitch
- Department of PsychiatryColumbia University Vagelos College of Physicians and SurgeonsNew YorkNYUSA
- Center for Molecular RecognitionColumbia University Vagelos College of Physicians and SurgeonsNew YorkNYUSA
- Department of PharmacologyColumbia University Vagelos College of Physicians and SurgeonsNew YorkNYUSA
- Division of Molecular TherapeuticsNew York State Psychiatric InstituteNew YorkNYUSA
| | - Matthias Quick
- Department of PsychiatryColumbia University Vagelos College of Physicians and SurgeonsNew YorkNYUSA
- Center for Molecular RecognitionColumbia University Vagelos College of Physicians and SurgeonsNew YorkNYUSA
- Division of Molecular TherapeuticsNew York State Psychiatric InstituteNew YorkNYUSA
| | - Poul Nissen
- Department of Molecular Biology and GeneticsDanish Research Institute of Translational Neuroscience—DANDRITENordic‐EMBL Partnership for Molecular MedicineAarhus UniversityAarhus CDenmark
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24
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Bhat S, El-Kasaby A, Freissmuth M, Sucic S. Functional and Biochemical Consequences of Disease Variants in Neurotransmitter Transporters: A Special Emphasis on Folding and Trafficking Deficits. Pharmacol Ther 2020; 222:107785. [PMID: 33310157 PMCID: PMC7612411 DOI: 10.1016/j.pharmthera.2020.107785] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 12/02/2020] [Indexed: 01/30/2023]
Abstract
Neurotransmitters, such as γ-aminobutyric acid, glutamate, acetyl choline, glycine and the monoamines, facilitate the crosstalk within the central nervous system. The designated neurotransmitter transporters (NTTs) both release and take up neurotransmitters to and from the synaptic cleft. NTT dysfunction can lead to severe pathophysiological consequences, e.g. epilepsy, intellectual disability, or Parkinson’s disease. Genetic point mutations in NTTs have recently been associated with the onset of various neurological disorders. Some of these mutations trigger folding defects in the NTT proteins. Correct folding is a prerequisite for the export of NTTs from the endoplasmic reticulum (ER) and the subsequent trafficking to their pertinent site of action, typically at the plasma membrane. Recent studies have uncovered some of the key features in the molecular machinery responsible for transporter protein folding, e.g., the role of heat shock proteins in fine-tuning the ER quality control mechanisms in cells. The therapeutic significance of understanding these events is apparent from the rising number of reports, which directly link different pathological conditions to NTT misfolding. For instance, folding-deficient variants of the human transporters for dopamine or GABA lead to infantile parkinsonism/dystonia and epilepsy, respectively. From a therapeutic point of view, some folding-deficient NTTs are amenable to functional rescue by small molecules, known as chemical and pharmacological chaperones.
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Affiliation(s)
- Shreyas Bhat
- Institute of Pharmacology and the Gaston H. Glock Research Laboratories for Exploratory Drug Development, Center of Physiology and Pharmacology, Medical University of Vienna, A-1090 Vienna, Austria
| | - Ali El-Kasaby
- Institute of Pharmacology and the Gaston H. Glock Research Laboratories for Exploratory Drug Development, Center of Physiology and Pharmacology, Medical University of Vienna, A-1090 Vienna, Austria
| | - Michael Freissmuth
- Institute of Pharmacology and the Gaston H. Glock Research Laboratories for Exploratory Drug Development, Center of Physiology and Pharmacology, Medical University of Vienna, A-1090 Vienna, Austria
| | - Sonja Sucic
- Institute of Pharmacology and the Gaston H. Glock Research Laboratories for Exploratory Drug Development, Center of Physiology and Pharmacology, Medical University of Vienna, A-1090 Vienna, Austria.
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25
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Radzikowska U, Ding M, Tan G, Zhakparov D, Peng Y, Wawrzyniak P, Wang M, Li S, Morita H, Altunbulakli C, Reiger M, Neumann AU, Lunjani N, Traidl-Hoffmann C, Nadeau KC, O'Mahony L, Akdis C, Sokolowska M. Distribution of ACE2, CD147, CD26, and other SARS-CoV-2 associated molecules in tissues and immune cells in health and in asthma, COPD, obesity, hypertension, and COVID-19 risk factors. Allergy 2020; 75:2829-2845. [PMID: 32496587 DOI: 10.1101/2020.05.14.090332] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 05/20/2020] [Accepted: 05/25/2020] [Indexed: 05/19/2023]
Abstract
BACKGROUND Morbidity and mortality from COVID-19 caused by novel coronavirus SARS-CoV-2 is accelerating worldwide, and novel clinical presentations of COVID-19 are often reported. The range of human cells and tissues targeted by SARS-CoV-2, its potential receptors and associated regulating factors are still largely unknown. The aim of our study was to analyze the expression of known and potential SARS-CoV-2 receptors and related molecules in the extensive collection of primary human cells and tissues from healthy subjects of different age and from patients with risk factors and known comorbidities of COVID-19. METHODS We performed RNA sequencing and explored available RNA-Seq databases to study gene expression and co-expression of ACE2, CD147 (BSG), and CD26 (DPP4) and their direct and indirect molecular partners in primary human bronchial epithelial cells, bronchial and skin biopsies, bronchoalveolar lavage fluid, whole blood, peripheral blood mononuclear cells (PBMCs), monocytes, neutrophils, DCs, NK cells, ILC1, ILC2, ILC3, CD4+ and CD8+ T cells, B cells, and plasmablasts. We analyzed the material from healthy children and adults, and from adults in relation to their disease or COVID-19 risk factor status. RESULTS ACE2 and TMPRSS2 were coexpressed at the epithelial sites of the lung and skin, whereas CD147 (BSG), cyclophilins (PPIA andPPIB), CD26 (DPP4), and related molecules were expressed in both epithelium and in immune cells. We also observed a distinct age-related expression profile of these genes in the PBMCs and T cells from healthy children and adults. Asthma, COPD, hypertension, smoking, obesity, and male gender status generally led to the higher expression of ACE2- and CD147-related genes in the bronchial biopsy, BAL, or blood. Additionally, CD147-related genes correlated positively with age and BMI. Interestingly, we also observed higher expression of CD147-related genes in the lesional skin of patients with atopic dermatitis. CONCLUSIONS Our data suggest different receptor repertoire potentially involved in the SARS-CoV-2 infection at the epithelial barriers and in the immune cells. Altered expression of these receptors related to age, gender, obesity and smoking, as well as with the disease status, might contribute to COVID-19 morbidity and severity patterns.
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Affiliation(s)
- Urszula Radzikowska
- Swiss Institute of Allergy and Asthma Research (SIAF), University of Zurich, Davos, Switzerland
- Christine Kühne - Center for Research and Education (CK-CARE), Davos, Switzerland
- Department of Regenerative Medicine and Immune Regulation, Medical University of Bialystok, Bialystok, Poland
| | - Mei Ding
- Swiss Institute of Allergy and Asthma Research (SIAF), University of Zurich, Davos, Switzerland
- Christine Kühne - Center for Research and Education (CK-CARE), Davos, Switzerland
- Department of Allergology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Ge Tan
- Swiss Institute of Allergy and Asthma Research (SIAF), University of Zurich, Davos, Switzerland
- Functional Genomic Centre Zurich, ETH Zurich/University of Zurich, Zurich, Switzerland
| | - Damir Zhakparov
- Swiss Institute of Allergy and Asthma Research (SIAF), University of Zurich, Davos, Switzerland
| | - Yaqi Peng
- Swiss Institute of Allergy and Asthma Research (SIAF), University of Zurich, Davos, Switzerland
- Christine Kühne - Center for Research and Education (CK-CARE), Davos, Switzerland
- Otorhinolaryngology Hospital, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Paulina Wawrzyniak
- Swiss Institute of Allergy and Asthma Research (SIAF), University of Zurich, Davos, Switzerland
- Christine Kühne - Center for Research and Education (CK-CARE), Davos, Switzerland
- Division of Clinical Chemistry and Biochemistry, University Children`s Hospital Zurich, Zurich, Switzerland
- Children`s Research Center, University Children`s Hospital Zurich, Zurich, Switzerland
| | - Ming Wang
- Swiss Institute of Allergy and Asthma Research (SIAF), University of Zurich, Davos, Switzerland
- Christine Kühne - Center for Research and Education (CK-CARE), Davos, Switzerland
- Department of Otolaryngology, Head and Neck Surgery, Beijing TongRen Hospital, Capital Medical University and the Beijing Key Laboratory of Nasal Diseases, Beijing Institute of Otolaryngology, Beijing, China
| | - Shuo Li
- Swiss Institute of Allergy and Asthma Research (SIAF), University of Zurich, Davos, Switzerland
- Department of Cancer Immunology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway
| | - Hideaki Morita
- Swiss Institute of Allergy and Asthma Research (SIAF), University of Zurich, Davos, Switzerland
- Department of Allergy and Clinical Immunology, National Research Institute for Child Health and Development, Tokyo, Japan
| | - Can Altunbulakli
- Swiss Institute of Allergy and Asthma Research (SIAF), University of Zurich, Davos, Switzerland
- Christine Kühne - Center for Research and Education (CK-CARE), Davos, Switzerland
| | - Matthias Reiger
- Chair and Institute of Environmental Medicine, UNIKA-T, Technical University of Munich and Helmholtz Zentrum Munchen, Augsburg, Germany
| | - Avidan U Neumann
- Chair and Institute of Environmental Medicine, UNIKA-T, Technical University of Munich and Helmholtz Zentrum Munchen, Augsburg, Germany
- Institute of Computational Biology (ICB), Helmholtz Zentrum Munchen, Munich, Germany
- Institute of Experimental Medicine (IEM), Czech Academy of Sciences, Prague, Czech Republic
| | - Nonhlanhla Lunjani
- Swiss Institute of Allergy and Asthma Research (SIAF), University of Zurich, Davos, Switzerland
- Christine Kühne - Center for Research and Education (CK-CARE), Davos, Switzerland
| | - Claudia Traidl-Hoffmann
- Christine Kühne - Center for Research and Education (CK-CARE), Davos, Switzerland
- Chair and Institute of Environmental Medicine, UNIKA-T, Technical University of Munich and Helmholtz Zentrum Munchen, Augsburg, Germany
| | - Kari C Nadeau
- Sean N Parker Centre for Allergy and Asthma Research at Stanford University, Department of Medicine, Stanford University School of Medicine, Stanford, USA
| | - Liam O'Mahony
- Swiss Institute of Allergy and Asthma Research (SIAF), University of Zurich, Davos, Switzerland
- Department of Medicine and School of Microbiology, APC Microbiome Ireland, National University of Ireland, Cork, Ireland
| | - Cezmi Akdis
- Swiss Institute of Allergy and Asthma Research (SIAF), University of Zurich, Davos, Switzerland
- Christine Kühne - Center for Research and Education (CK-CARE), Davos, Switzerland
| | - Milena Sokolowska
- Swiss Institute of Allergy and Asthma Research (SIAF), University of Zurich, Davos, Switzerland
- Christine Kühne - Center for Research and Education (CK-CARE), Davos, Switzerland
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26
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Radzikowska U, Ding M, Tan G, Zhakparov D, Peng Y, Wawrzyniak P, Wang M, Li S, Morita H, Altunbulakli C, Reiger M, Neumann AU, Lunjani N, Traidl‐Hoffmann C, Nadeau KC, O’Mahony L, Akdis C, Sokolowska M. Distribution of ACE2, CD147, CD26, and other SARS-CoV-2 associated molecules in tissues and immune cells in health and in asthma, COPD, obesity, hypertension, and COVID-19 risk factors. Allergy 2020; 75:2829-2845. [PMID: 32496587 PMCID: PMC7300910 DOI: 10.1111/all.14429] [Citation(s) in RCA: 340] [Impact Index Per Article: 85.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 05/20/2020] [Accepted: 05/25/2020] [Indexed: 02/06/2023]
Abstract
Background Morbidity and mortality from COVID‐19 caused by novel coronavirus SARS‐CoV‐2 is accelerating worldwide, and novel clinical presentations of COVID‐19 are often reported. The range of human cells and tissues targeted by SARS‐CoV‐2, its potential receptors and associated regulating factors are still largely unknown. The aim of our study was to analyze the expression of known and potential SARS‐CoV‐2 receptors and related molecules in the extensive collection of primary human cells and tissues from healthy subjects of different age and from patients with risk factors and known comorbidities of COVID‐19. Methods We performed RNA sequencing and explored available RNA‐Seq databases to study gene expression and co‐expression of ACE2, CD147 (BSG), and CD26 (DPP4) and their direct and indirect molecular partners in primary human bronchial epithelial cells, bronchial and skin biopsies, bronchoalveolar lavage fluid, whole blood, peripheral blood mononuclear cells (PBMCs), monocytes, neutrophils, DCs, NK cells, ILC1, ILC2, ILC3, CD4+ and CD8+ T cells, B cells, and plasmablasts. We analyzed the material from healthy children and adults, and from adults in relation to their disease or COVID‐19 risk factor status. Results ACE2 and TMPRSS2 were coexpressed at the epithelial sites of the lung and skin, whereas CD147 (BSG), cyclophilins (PPIA andPPIB), CD26 (DPP4), and related molecules were expressed in both epithelium and in immune cells. We also observed a distinct age‐related expression profile of these genes in the PBMCs and T cells from healthy children and adults. Asthma, COPD, hypertension, smoking, obesity, and male gender status generally led to the higher expression of ACE2‐ and CD147‐related genes in the bronchial biopsy, BAL, or blood. Additionally, CD147‐related genes correlated positively with age and BMI. Interestingly, we also observed higher expression of CD147‐related genes in the lesional skin of patients with atopic dermatitis. Conclusions Our data suggest different receptor repertoire potentially involved in the SARS‐CoV‐2 infection at the epithelial barriers and in the immune cells. Altered expression of these receptors related to age, gender, obesity and smoking, as well as with the disease status, might contribute to COVID‐19 morbidity and severity patterns.
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Affiliation(s)
- Urszula Radzikowska
- Swiss Institute of Allergy and Asthma Research (SIAF) University of Zurich Davos Switzerland
- Christine Kühne – Center for Research and Education (CK‐CARE) Davos Switzerland
- Department of Regenerative Medicine and Immune Regulation Medical University of Bialystok Bialystok Poland
| | - Mei Ding
- Swiss Institute of Allergy and Asthma Research (SIAF) University of Zurich Davos Switzerland
- Christine Kühne – Center for Research and Education (CK‐CARE) Davos Switzerland
- Department of Allergology Zhongnan Hospital of Wuhan University Wuhan China
| | - Ge Tan
- Swiss Institute of Allergy and Asthma Research (SIAF) University of Zurich Davos Switzerland
- Functional Genomic Centre ZurichETH Zurich/University of Zurich Zurich Switzerland
| | - Damir Zhakparov
- Swiss Institute of Allergy and Asthma Research (SIAF) University of Zurich Davos Switzerland
| | - Yaqi Peng
- Swiss Institute of Allergy and Asthma Research (SIAF) University of Zurich Davos Switzerland
- Christine Kühne – Center for Research and Education (CK‐CARE) Davos Switzerland
- Otorhinolaryngology HospitalThe First Affiliated HospitalSun Yat‐sen University Guangzhou China
| | - Paulina Wawrzyniak
- Swiss Institute of Allergy and Asthma Research (SIAF) University of Zurich Davos Switzerland
- Christine Kühne – Center for Research and Education (CK‐CARE) Davos Switzerland
- Division of Clinical Chemistry and Biochemistry University Children`s Hospital Zurich Zurich Switzerland
- Children`s Research Center University Children`s Hospital Zurich Zurich Switzerland
| | - Ming Wang
- Swiss Institute of Allergy and Asthma Research (SIAF) University of Zurich Davos Switzerland
- Christine Kühne – Center for Research and Education (CK‐CARE) Davos Switzerland
- Department of Otolaryngology, Head and Neck Surgery Beijing TongRen HospitalCapital Medical University and the Beijing Key Laboratory of Nasal DiseasesBeijing Institute of Otolaryngology Beijing China
| | - Shuo Li
- Swiss Institute of Allergy and Asthma Research (SIAF) University of Zurich Davos Switzerland
- Department of Cancer Immunology Institute for Cancer ResearchOslo University Hospital Oslo Norway
| | - Hideaki Morita
- Swiss Institute of Allergy and Asthma Research (SIAF) University of Zurich Davos Switzerland
- Department of Allergy and Clinical Immunology National Research Institute for Child Health and Development Tokyo Japan
| | - Can Altunbulakli
- Swiss Institute of Allergy and Asthma Research (SIAF) University of Zurich Davos Switzerland
- Christine Kühne – Center for Research and Education (CK‐CARE) Davos Switzerland
| | - Matthias Reiger
- Chair and Institute of Environmental Medicine UNIKA‐TTechnical University of Munich and Helmholtz Zentrum Munchen Augsburg Germany
| | - Avidan U. Neumann
- Chair and Institute of Environmental Medicine UNIKA‐TTechnical University of Munich and Helmholtz Zentrum Munchen Augsburg Germany
- Institute of Computational Biology (ICB) Helmholtz Zentrum Munchen Munich Germany
- Institute of Experimental Medicine (IEM) Czech Academy of Sciences Prague Czech Republic
| | - Nonhlanhla Lunjani
- Swiss Institute of Allergy and Asthma Research (SIAF) University of Zurich Davos Switzerland
- Christine Kühne – Center for Research and Education (CK‐CARE) Davos Switzerland
| | - Claudia Traidl‐Hoffmann
- Christine Kühne – Center for Research and Education (CK‐CARE) Davos Switzerland
- Chair and Institute of Environmental Medicine UNIKA‐TTechnical University of Munich and Helmholtz Zentrum Munchen Augsburg Germany
| | - Kari C. Nadeau
- Sean N Parker Centre for Allergy and Asthma Research at Stanford University Department of Medicine Stanford University School of Medicine Stanford USA
| | - Liam O’Mahony
- Swiss Institute of Allergy and Asthma Research (SIAF) University of Zurich Davos Switzerland
- Department of Medicine and School of Microbiology APC Microbiome IrelandNational University of Ireland Cork Ireland
| | - Cezmi Akdis
- Swiss Institute of Allergy and Asthma Research (SIAF) University of Zurich Davos Switzerland
- Christine Kühne – Center for Research and Education (CK‐CARE) Davos Switzerland
| | - Milena Sokolowska
- Swiss Institute of Allergy and Asthma Research (SIAF) University of Zurich Davos Switzerland
- Christine Kühne – Center for Research and Education (CK‐CARE) Davos Switzerland
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Low temperature bacterial expression of the neutral amino acid transporters SLC1A5 (ASCT2), and SLC6A19 (B0AT1). Mol Biol Rep 2020; 47:7283-7289. [PMID: 32772343 PMCID: PMC7415195 DOI: 10.1007/s11033-020-05717-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Accepted: 08/02/2020] [Indexed: 11/28/2022]
Abstract
It is well established that Escherichia coli represents a powerful tool for the over-expression of human proteins for structure/function studies. In many cases, such as for membrane transporters, the bacterial toxicity or the aggregation of the target protein hamper the expression limiting the application of this tool. The aim of this study was finding the appropriate conditions for the expression of reluctant proteins that is the human neutral amino acid transporters ASCT2 and B0AT1, that have great relevance to human health in cancer therapy and in COVID-19 research, respectively. The cDNAs coding for the proteins of interest were cloned in the pCOLD I vector and different E. coli strains (BL21 codon plus RIL, and RosettaGami2) were cultured in absence or in presence of glucose (0.5–1%), at low temperature (15 °C), and low inducer concentrations (10–100 µM). Cell growth and protein production were monitored by optical density measurements and western blotting assay, respectively. Even though in different conditions, the expression of both amino acid transporters was obtained.Reducing the growth rate of specific E. coli strains by lowering the temperature and the IPTG concentration, together with the addition of glucose, two reluctant human neutral amino acid transporters have been expressed in E. coli. The results have a potentially great interest in drug discovery since ASCT2 is an acknowledged target of anticancer therapy, and B0AT1 together with ACE2 is part of a receptor for the SARS-Cov-2 RBD proteins.
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28
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Bhowmick SS, Lang AE. Movement Disorders and Renal Diseases. Mov Disord Clin Pract 2020; 7:763-779. [PMID: 33043074 DOI: 10.1002/mdc3.13005] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 06/03/2020] [Accepted: 06/05/2020] [Indexed: 02/06/2023] Open
Abstract
Movement disorders often emerge from the interplay of complex pathophysiological processes involving the kidneys and the nervous system. Tremor, myoclonus, ataxia, chorea, and parkinsonism can occur in the context of renal dysfunction (azotemia and electrolyte abnormalities) or they can be part of complications of its management (dialysis and renal transplantation). On the other hand, myoglobinuria from rhabdomyolysis in status dystonicus and certain drugs used in the management of movement disorders can cause nephrotoxicity. Distinct from these well-recognized associations, it is important to appreciate that there are several inherited and acquired disorders in which movement abnormalities do not occur as a consequence of renal dysfunction or vice versa but are manifestations of common pathophysiological processes affecting the nervous system and the kidneys. These disorders are the emphasis of this review. Increasing awareness of these conditions among neurologists may help them to identify renal involvement earlier, take timely intervention by anticipating complications and focus on therapies targeting common mechanisms in addition to symptomatic management of movement disorders. Recognition of renal impairment in a patient with complex neurological presentation may narrow down the differentials and aid in reaching a definite diagnosis.
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Affiliation(s)
- Suvorit S Bhowmick
- Division of Neurology, Department of Medicine, Morton and Gloria Shulman Movement Disorders Clinic and the Edmond J. Safra Program in Parkinson's Disease, Toronto Western Hospital University Health Network Toronto Ontario Canada
| | - Anthony E Lang
- Division of Neurology, Department of Medicine, Morton and Gloria Shulman Movement Disorders Clinic and the Edmond J. Safra Program in Parkinson's Disease, Toronto Western Hospital University Health Network Toronto Ontario Canada
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29
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Yadav A, Shah N, Tiwari PK, Javed K, Cheng Q, Aidhen IS, Bröer S. Novel Chemical Scaffolds to Inhibit the Neutral Amino Acid Transporter B 0AT1 (SLC6A19), a Potential Target to Treat Metabolic Diseases. Front Pharmacol 2020; 11:140. [PMID: 32180718 PMCID: PMC7059793 DOI: 10.3389/fphar.2020.00140] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Accepted: 02/03/2020] [Indexed: 11/13/2022] Open
Abstract
Lack of B0AT1 (SLC6A19) partially protects mice against the onset of non-alcoholic steatohepatitis (NASH). To achieve a similar outcome through pharmacological treatment, we improved previously identified inhibitors of B0AT1 by medicinal chemistry and identified second generation inhibitors by high through-put screening. Modified diarylmethine compounds inhibited B0AT1 with IC50 values ranging from 8-90 μM. A second generation of inhibitors was derived from high-throughput screening and showed higher affinity (IC50 of 1-15 μM) and strong selectivity against amino acid transporters with similar substrate specificity, such as ASCT2 (SLC1A5) and LAT1 (SLC7A5). All compounds were unrelated to B0AT1 substrates, but were likely to bind in the vicinity of the substrate binding site.
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Affiliation(s)
- Aditya Yadav
- Research School of Biology, Australian National University, Canberra, ACT, Australia
| | - Nishank Shah
- Research School of Biology, Australian National University, Canberra, ACT, Australia
| | | | - Kiran Javed
- Research School of Biology, Australian National University, Canberra, ACT, Australia
| | - Qi Cheng
- Research School of Biology, Australian National University, Canberra, ACT, Australia
| | | | - Stefan Bröer
- Research School of Biology, Australian National University, Canberra, ACT, Australia
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30
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Haijes H, Prinsen HC, de Sain-van der Velden MG, Verhoeven-Duif NM, van Hasselt PM, Jans JJ. Accurate discrimination of Hartnup disorder from other aminoacidurias using a diagnostic ratio. Mol Genet Metab Rep 2020; 22:100551. [PMID: 31908951 PMCID: PMC6938934 DOI: 10.1016/j.ymgmr.2019.100551] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Revised: 11/11/2019] [Accepted: 12/13/2019] [Indexed: 11/18/2022] Open
Abstract
Introduction Hartnup disorder is caused by a deficiency of the sodium dependent B0 AT1 neutral amino acid transporter in the proximal kidney tubules and jejunum. Biochemically, Hartnup disorder is diagnosed via amino acid excretion patterns. However, these patterns can closely resemble amino acid excretion patterns of generalized aminoaciduria, which may induce a risk for misdiagnosis and preclusion from treatment. Here we explore whether calculating a diagnostic ratio could facilitate correct discrimination of Hartnup disorder from other aminoacidurias. Methods 27 amino acid excretion patterns from 11 patients with genetically confirmed Hartnup disorder were compared to 68 samples of 16 patients with other aminoacidurias. Amino acid fold changes were calculated by dividing the quantified excretion values over the upper limit of the age-adjusted reference value. Results Increased excretion of amino acids is not restricted to amino acids classically related to Hartnup disorder ("Hartnup amino acids", HAA), but also includes many other amino acids, not classically related to Hartnup disorder ("other amino acids", OAA). The fold change ratio of HAA over OAA was 6.1 (range: 2.4-9.6) in the Hartnup cohort, versus 0.2 (range: 0.0-1.6) in the aminoaciduria cohort (p < .0001), without any overlap observed between the cohorts. Discussion Excretion values of amino acids not classically related to Hartnup disorder are frequently elevated in patients with Hartnup disorder, which may cause misdiagnosis as generalized aminoaciduria and preclusion from vitamin B3 treatment. Calculation of the HAA/OAA ratio improves diagnostic differentiation of Hartnup disorder from other aminoacidurias.
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Affiliation(s)
- H.A. Haijes
- Department of Genetics, Section Metabolic Diagnostics, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
- Department of Pediatrics, Section Metabolic Disorders, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Hubertus C.M.T. Prinsen
- Department of Genetics, Section Metabolic Diagnostics, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | | | - Nanda M. Verhoeven-Duif
- Department of Genetics, Section Metabolic Diagnostics, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Peter M. van Hasselt
- Department of Pediatrics, Section Metabolic Disorders, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Judith J.M. Jans
- Department of Genetics, Section Metabolic Diagnostics, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
- Corresponding author at: Wilhelmina Children's Hospital, University Medical Center Utrecht, Lundlaan 6, 3584 EA Utrecht, The Netherlands.
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31
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Yahyaoui R, Pérez-Frías J. Amino Acid Transport Defects in Human Inherited Metabolic Disorders. Int J Mol Sci 2019; 21:ijms21010119. [PMID: 31878022 PMCID: PMC6981491 DOI: 10.3390/ijms21010119] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 12/12/2019] [Accepted: 12/18/2019] [Indexed: 02/07/2023] Open
Abstract
Amino acid transporters play very important roles in nutrient uptake, neurotransmitter recycling, protein synthesis, gene expression, cell redox balance, cell signaling, and regulation of cell volume. With regard to transporters that are closely connected to metabolism, amino acid transporter-associated diseases are linked to metabolic disorders, particularly when they involve different organs, cell types, or cell compartments. To date, 65 different human solute carrier (SLC) families and more than 400 transporter genes have been identified, including 11 that are known to include amino acid transporters. This review intends to summarize and update all the conditions in which a strong association has been found between an amino acid transporter and an inherited metabolic disorder. Many of these inherited disorders have been identified in recent years. In this work, the physiological functions of amino acid transporters will be described by the inherited diseases that arise from transporter impairment. The pathogenesis, clinical phenotype, laboratory findings, diagnosis, genetics, and treatment of these disorders are also briefly described. Appropriate clinical and diagnostic characterization of the underlying molecular defect may give patients the opportunity to avail themselves of appropriate therapeutic options in the future.
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Affiliation(s)
- Raquel Yahyaoui
- Laboratory of Metabolic Disorders and Newborn Screening Center of Eastern Andalusia, Málaga Regional University Hospital, 29011 Málaga, Spain
- Grupo Endocrinología y Nutrición, Diabetes y Obesidad, Instituto de Investigación Biomédica de Málaga-IBIMA, 29010 Málaga, Spain
- Correspondence:
| | - Javier Pérez-Frías
- Grupo Multidisciplinar de Investigación Pediátrica, Instituto de Investigación Biomédica de Málaga-IBIMA, 29010 Málaga, Spain;
- Departamento de Farmacología y Pediatría, Facultad de Medicina, Universidad de Málaga, 29010 Málaga, Spain
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32
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Pillai NR, Yubero D, Shayota BJ, Oyarzábal A, Ghosh R, Sun Q, Azamian MS, Arjona C, Brandi N, Palau F, Lalani SR, Artuch R, García‐Cazorla A, Scott DA. Loss of CLTRN function produces a neuropsychiatric disorder and a biochemical phenotype that mimics Hartnup disease. Am J Med Genet A 2019; 179:2459-2468. [DOI: 10.1002/ajmg.a.61357] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Revised: 08/22/2019] [Accepted: 08/25/2019] [Indexed: 01/02/2023]
Affiliation(s)
- Nishitha R. Pillai
- Department of Molecular and Human Genetics Baylor College of Medicine Houston Texas
- Texas Children's Hospital Houston Texas
| | - Delia Yubero
- Department of Genetics and Molecular Medicine‐IPER, Institut de Recerca Sant Joan de Déu and CIBERER (ISCIII) Hospital Sant Joan de Déu Barcelona Spain
| | - Brian J. Shayota
- Department of Molecular and Human Genetics Baylor College of Medicine Houston Texas
- Texas Children's Hospital Houston Texas
| | - Alfonso Oyarzábal
- Laboratory of Synaptic Metabolism, Institut de Recerca Sant Joan de Déu and CIBERER (ISCIII) Hospital Sant Joan de Déu Barcelona Spain
| | - Rajarshi Ghosh
- Department of Molecular and Human Genetics Baylor College of Medicine Houston Texas
- Baylor Genetics Laboratory Houston Texas
| | - Qin Sun
- Department of Molecular and Human Genetics Baylor College of Medicine Houston Texas
- Baylor Genetics Laboratory Houston Texas
| | - Mahshid S. Azamian
- Department of Molecular and Human Genetics Baylor College of Medicine Houston Texas
- Texas Children's Hospital Houston Texas
| | - Cesar Arjona
- Department of Genetics and Molecular Medicine‐IPER, Institut de Recerca Sant Joan de Déu and CIBERER (ISCIII) Hospital Sant Joan de Déu Barcelona Spain
| | - Núria Brandi
- Department of Genetics and Molecular Medicine‐IPER, Institut de Recerca Sant Joan de Déu and CIBERER (ISCIII) Hospital Sant Joan de Déu Barcelona Spain
- School of Medicine Universitat de Barcelona Barcelona Spain
| | - Francesc Palau
- Department of Genetics and Molecular Medicine‐IPER, Institut de Recerca Sant Joan de Déu and CIBERER (ISCIII) Hospital Sant Joan de Déu Barcelona Spain
- Division of Pediatrics University of Barcelona School of Medicine and Health Sciences, and Institute of Medicine and Dermatology, Hospital Clínic Barcelona Spain
| | - Seema R. Lalani
- Department of Molecular and Human Genetics Baylor College of Medicine Houston Texas
- Texas Children's Hospital Houston Texas
| | - Rafael Artuch
- Department of Clinical Biochemistry, Institut de Recerca Sant Joan de Déu and CIBERER (ISCIII) Hospital Sant Joan de Déu Barcelona Spain
| | - Angeles García‐Cazorla
- Laboratory of Synaptic Metabolism, Institut de Recerca Sant Joan de Déu and CIBERER (ISCIII) Hospital Sant Joan de Déu Barcelona Spain
- Neurometabolic Unit, Department of Neurology Institut de Recerca, Sant Joan de Déu metabERN and CIBERER (ISCIII), Hospital Sant Joan de Déu Barcelona Spain
| | - Daryl A. Scott
- Department of Molecular and Human Genetics Baylor College of Medicine Houston Texas
- Texas Children's Hospital Houston Texas
- Department of Molecular Physiology and Biophysics Baylor College of Medicine Houston Texas
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Javed K, Bröer S. Mice Lacking the Intestinal and Renal Neutral Amino Acid Transporter SLC6A19 Demonstrate the Relationship between Dietary Protein Intake and Amino Acid Malabsorption. Nutrients 2019; 11:E2024. [PMID: 31470570 PMCID: PMC6770948 DOI: 10.3390/nu11092024] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 08/22/2019] [Accepted: 08/23/2019] [Indexed: 12/15/2022] Open
Abstract
Dietary protein restriction has beneficial impacts on metabolic health. B0AT1 (SLC6A19) is the major transporter of neutral amino acids at the intestinal epithelia and absorbs the bulk of the diet-derived neutral amino acids from the intestinal lumen. It also reabsorbs neutral amino acids in the renal proximal tubules. Mice lacking B0AT1 show cellular outcomes of protein restriction, such as high FGF21 levels and low mTORC1 activity. Moreover, they have improved glucose homeostasis and resist diet-induced obesity. In this study, we investigated the relationship between protein restriction and dietary protein intake in C57Bl6/J wild-type (wt) and SLC6A19-knockout (SLC6A19ko) mice. When SLC6A19ko mice were fed diets containing 5%, 25%, or 52% of their total calories derived from protein, no differences in food intake or weight gain were observed. All essential amino acids significantly positively correlated with increasing dietary casein content in the wt mice. The SLC6A19ko mice showed reduced postprandial levels of essential amino acids in plasma, particularly following high-protein diets. Upon fasting, essential amino acids were the same in the wt and SLC6A19ko mice due to reduced amino acid catabolism. Bacterial metabolites originating from amino acid fermentation correlated with the dietary protein content, but showed a complex profile in the blood of the SLC6A19ko mice. This study highlights the potential of SLC6A19 as a knock-out or inhibition target to induce protein restriction for the treatment of metabolic disorders.
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Affiliation(s)
- Kiran Javed
- Research School of Biology, The Australian National University, Canberra, ACT 2600, Australia
| | - Stefan Bröer
- Research School of Biology, The Australian National University, Canberra, ACT 2600, Australia.
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Amino acid transporters in the regulation of insulin secretion and signalling. Biochem Soc Trans 2019; 47:571-590. [PMID: 30936244 DOI: 10.1042/bst20180250] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Revised: 02/24/2019] [Accepted: 02/25/2019] [Indexed: 01/02/2023]
Abstract
Amino acids are increasingly recognised as modulators of nutrient disposal, including their role in regulating blood glucose through interactions with insulin signalling. More recently, cellular membrane transporters of amino acids have been shown to form a pivotal part of this regulation as they are primarily responsible for controlling cellular and circulating amino acid concentrations. The availability of amino acids regulated by transporters can amplify insulin secretion and modulate insulin signalling in various tissues. In addition, insulin itself can regulate the expression of numerous amino acid transporters. This review focuses on amino acid transporters linked to the regulation of insulin secretion and signalling with a focus on those of the small intestine, pancreatic β-islet cells and insulin-responsive tissues, liver and skeletal muscle. We summarise the role of the amino acid transporter B0AT1 (SLC6A19) and peptide transporter PEPT1 (SLC15A1) in the modulation of global insulin signalling via the liver-secreted hormone fibroblast growth factor 21 (FGF21). The role of vesicular vGLUT (SLC17) and mitochondrial SLC25 transporters in providing glutamate for the potentiation of insulin secretion is covered. We also survey the roles SNAT (SLC38) family and LAT1 (SLC7A5) amino acid transporters play in the regulation of and by insulin in numerous affective tissues. We hypothesise the small intestine amino acid transporter B0AT1 represents a crucial nexus between insulin, FGF21 and incretin hormone signalling pathways. The aim is to give an integrated overview of the important role amino acid transporters have been found to play in insulin-regulated nutrient signalling.
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Indole-3-Propionic Acid, a Tryptophan-Derived Bacterial Metabolite, Reduces Weight Gain in Rats. Nutrients 2019; 11:nu11030591. [PMID: 30862081 PMCID: PMC6471155 DOI: 10.3390/nu11030591] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 03/05/2019] [Accepted: 03/10/2019] [Indexed: 12/20/2022] Open
Abstract
Recent evidence suggests that tryptophan, an essential amino acid, may exert biological effects by means of tryptophan-derived gut bacteria products. We evaluated the potential contribution of tryptophan-derived bacterial metabolites to body weight gain. The study comprised three experimental series performed on separate groups of male, Sprague-Dawley rats: (i) rats on standard laboratory diet treated with water solution of neomycin, an antibiotic, or tap water (controls-1); (ii) rats on standard diet (controls-2) or tryptophan-high (TH) or tryptophan-free (TF) diet; and (iii) rats treated with indole-3-propionic acid (I3P), a bacterial metabolite of tryptophan, or a vehicle (controls-3). (i) Rats treated with neomycin showed a significantly higher weight gain but lower stool and blood concentration of I3P than controls-1. (ii) The TH group showed significantly smaller increases in body weight but higher stool and plasma concentration of I3P than controls-2. In contrast, the TF group showed a decrease in body weight, decreased total serum protein and a significant increase in urine output. (iii) Rats treated with I3P showed significantly smaller weight gain than controls-3. Our study suggests that I3P, a gut bacteria metabolite of tryptophan, contributes to changes in body weight gain produced by antibiotics and tryptophan-rich diet.
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Abstract
The small intestine mediates the absorption of amino acids after ingestion of protein and sustains the supply of amino acids to all tissues. The small intestine is an important contributor to plasma amino acid homeostasis, while amino acid transport in the large intestine is more relevant for bacterial metabolites and fluid secretion. A number of rare inherited disorders have contributed to the identification of amino acid transporters in epithelial cells of the small intestine, in particular cystinuria, lysinuric protein intolerance, Hartnup disorder, iminoglycinuria, and dicarboxylic aminoaciduria. These are most readily detected by analysis of urine amino acids, but typically also affect intestinal transport. The genes underlying these disorders have all been identified. The remaining transporters were identified through molecular cloning techniques to the extent that a comprehensive portrait of functional cooperation among transporters of intestinal epithelial cells is now available for both the basolateral and apical membranes. Mouse models of most intestinal transporters illustrate their contribution to amino acid homeostasis and systemic physiology. Intestinal amino acid transport activities can vary between species, but these can now be explained as differences of amino acid transporter distribution along the intestine. © 2019 American Physiological Society. Compr Physiol 9:343-373, 2019.
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Affiliation(s)
- Stefan Bröer
- Research School of Biology, The Australian National University, Canberra, ACT 2601, Australia
| | - Stephen J Fairweather
- Research School of Biology, The Australian National University, Canberra, ACT 2601, Australia
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37
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Development of Biomarkers for Inhibition of SLC6A19 (B⁰AT1)-A Potential Target to Treat Metabolic Disorders. Int J Mol Sci 2018; 19:ijms19113597. [PMID: 30441827 PMCID: PMC6274964 DOI: 10.3390/ijms19113597] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Revised: 11/07/2018] [Accepted: 11/08/2018] [Indexed: 12/18/2022] Open
Abstract
Recent studies have established that dietary protein restriction improves metabolic health and glucose homeostasis. SLC6A19 (B⁰AT1) is the major neutral amino acid transporter in the intestine and carries out the bulk of amino acid absorption from the diet. Mice lacking SLC6A19 show signs of protein restriction, have improved glucose tolerance, and are protected from diet-induced obesity. Pharmacological blockage of this transporter could be used to induce protein restriction and to treat metabolic diseases such as type 2 diabetes. A few novel inhibitors of SLC6A19 have recently been identified using in vitro compound screening, but it remains unclear whether these compounds block the transporter in vivo. To evaluate the efficacy of SLC6A19 inhibitors biomarkers are required that can reliably detect successful inhibition of the transporter in mice. A gas chromatography mass spectrometry (GC-MS)-based untargeted metabolomics approach was used to discriminate global metabolite profiles in plasma, urine and faecal samples from SLC6A19ko and wt mice. Due to inefficient absorption in the intestine and lack of reabsorption in the kidney, significantly elevated amino acids levels were observed in urine and faecal samples. By contrast, a few neutral amino acids were reduced in the plasma of male SLC6A19ko mice as compared to other biological samples. Metabolites of bacterial protein fermentation such as p-cresol glucuronide and 3-indole-propionic acid were more abundant in SLC6A19ko mice, indicating protein malabsorption of dietary amino acids. Consistently, plasma appearance rates of [14C]-labelled neutral amino acids were delayed in SLC6A19ko mice as compared to wt after intra-gastric administration of a mixture of amino acids. Receiver operating characteristic (ROC) curve analysis was used to validate the potential use of these metabolites as biomarkers. These findings provide putative metabolite biomarkers that can be used to detect protein malabsorption and the inhibition of this transporter in intestine and kidney.
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38
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Zhu Y, Chen L, He J, Chen Y, Gou H, Ma L, Qu Y, Liu Y, Wang D, Zhu Y. Study of Seizure-Manifested Hartnup Disorder Case Induced By Novel Mutations in SLC6A19. Open Life Sci 2018; 13:22-27. [PMID: 33817063 PMCID: PMC7874744 DOI: 10.1515/biol-2018-0003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Accepted: 01/08/2018] [Indexed: 11/15/2022] Open
Abstract
AIM The aim of the study is to investigate a variation in the gene SLC6A19 in a female patient with Hartnup disorder manifested only by seizure. METHODS DNA samples collected from the patient and her parents were analyzed and twelve exons of the SLC6A19 gene were amplified and sequenced. RESULTS We found c.47C>T and c.1522G>A mutations in the gene SLC6A19 belonging to the patient, which are missense mutations inherited from her parents. The c.47C>T mutation is from her father and c.1522G>A is inherited from her mother. The parents are both heterozygous healthy carriers. CONCLUSION Two novel mutations of the SLC6A19 gene are revealed in the female patient with Hartnup disorder, exhibiting no typical dermatologic problems, but having dramatic neurological symptoms.
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Affiliation(s)
- Yanmei Zhu
- Department of Neurology, Second Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Li Chen
- Department of Neurology, Second Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Jia He
- Department of Neurology, Second Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Yan Chen
- Department of Neurology, Second Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Haiyan Gou
- Department of Neurology, Second Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Long Ma
- Second Department of Internal Medicine, Second Hospital of Heilongjiang Province, Harbin, China
| | - Youyang Qu
- Department of Neurology, Second Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Yu Liu
- Department of Neurology, Second Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Di Wang
- Department of Neurology, Second Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Yulan Zhu
- Department of Neurology, Second Affiliated Hospital of Harbin Medical University, Harbin, China
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Uemura S, Mochizuki T, Kurosaka G, Hashimoto T, Masukawa Y, Abe F. Functional analysis of human aromatic amino acid transporter MCT10/TAT1 using the yeast Saccharomyces cerevisiae. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2017; 1859:2076-2085. [DOI: 10.1016/j.bbamem.2017.07.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Revised: 07/03/2017] [Accepted: 07/24/2017] [Indexed: 01/08/2023]
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40
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Amino acid homeostasis and signalling in mammalian cells and organisms. Biochem J 2017; 474:1935-1963. [PMID: 28546457 PMCID: PMC5444488 DOI: 10.1042/bcj20160822] [Citation(s) in RCA: 306] [Impact Index Per Article: 43.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Revised: 03/08/2017] [Accepted: 03/10/2017] [Indexed: 12/19/2022]
Abstract
Cells have a constant turnover of proteins that recycle most amino acids over time. Net loss is mainly due to amino acid oxidation. Homeostasis is achieved through exchange of essential amino acids with non-essential amino acids and the transfer of amino groups from oxidised amino acids to amino acid biosynthesis. This homeostatic condition is maintained through an active mTORC1 complex. Under amino acid depletion, mTORC1 is inactivated. This increases the breakdown of cellular proteins through autophagy and reduces protein biosynthesis. The general control non-derepressable 2/ATF4 pathway may be activated in addition, resulting in transcription of genes involved in amino acid transport and biosynthesis of non-essential amino acids. Metabolism is autoregulated to minimise oxidation of amino acids. Systemic amino acid levels are also tightly regulated. Food intake briefly increases plasma amino acid levels, which stimulates insulin release and mTOR-dependent protein synthesis in muscle. Excess amino acids are oxidised, resulting in increased urea production. Short-term fasting does not result in depletion of plasma amino acids due to reduced protein synthesis and the onset of autophagy. Owing to the fact that half of all amino acids are essential, reduction in protein synthesis and amino acid oxidation are the only two measures to reduce amino acid demand. Long-term malnutrition causes depletion of plasma amino acids. The CNS appears to generate a protein-specific response upon amino acid depletion, resulting in avoidance of an inadequate diet. High protein levels, in contrast, contribute together with other nutrients to a reduction in food intake.
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Hill LJ, Williams AC. Meat Intake and the Dose of Vitamin B 3 - Nicotinamide: Cause of the Causes of Disease Transitions, Health Divides, and Health Futures? Int J Tryptophan Res 2017; 10:1178646917704662. [PMID: 28579801 PMCID: PMC5419340 DOI: 10.1177/1178646917704662] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Accepted: 03/15/2017] [Indexed: 12/26/2022] Open
Abstract
Meat and vitamin B3 - nicotinamide - intake was high during hunter-gatherer times. Intake then fell and variances increased during and after the Neolithic agricultural revolution. Health, height, and IQ deteriorated. Low dietary doses are buffered by 'welcoming' gut symbionts and tuberculosis that can supply nicotinamide, but this co-evolved homeostatic metagenomic strategy risks dysbioses and impaired resistance to pathogens. Vitamin B3 deficiency may now be common among the poor billions on a low-meat diet. Disease transitions to non-communicable inflammatory disorders (but longer lives) may be driven by positive 'meat transitions'. High doses of nicotinamide lead to reduced regulatory T cells and immune intolerance. Loss of no longer needed symbiotic 'old friends' compounds immunological over-reactivity to cause allergic and auto-immune diseases. Inhibition of nicotinamide adenine dinucleotide consumers and loss of methyl groups or production of toxins may cause cancers, metabolic toxicity, or neurodegeneration. An optimal dosage of vitamin B3 could lead to better health, but such a preventive approach needs more equitable meat distribution. Some people may require personalised doses depending on genetic make-up or, temporarily, when under stress.
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Affiliation(s)
- Lisa J Hill
- Neuroscience and Ophthalmology Research Group, Institute of Inflammation and Ageing, University of Birmingham, Birmingham, UK
| | - Adrian C Williams
- Department of Neurology, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
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Cheng Q, Shah N, Bröer A, Fairweather S, Jiang Y, Schmoll D, Corry B, Bröer S. Identification of novel inhibitors of the amino acid transporter B 0 AT1 (SLC6A19), a potential target to induce protein restriction and to treat type 2 diabetes. Br J Pharmacol 2017; 174:468-482. [PMID: 28176326 DOI: 10.1111/bph.13711] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Revised: 12/28/2016] [Accepted: 01/04/2017] [Indexed: 01/11/2023] Open
Abstract
BACKGROUND AND PURPOSE The neutral amino acid transporter B0 AT1 (SLC6A19) has recently been identified as a possible target to treat type 2 diabetes and related disorders. B0 AT1 mediates the Na+ -dependent uptake of all neutral amino acids. For surface expression and catalytic activity, B0 AT1 requires coexpression of collectrin (TMEM27). In this study, we established tools to identify and evaluate novel inhibitors of B0 AT1. EXPERIMENTAL APPROACH A CHO-based cell line was generated, stably expressing collectrin and B0 AT1. Using this cell line, a high-throughput screening assay was developed, which uses a fluorescent dye to detect depolarisation of the cell membrane during amino acid uptake via B0 AT1. In parallel to these functional assays, we ran a computational compound screen using AutoDock4 and a homology model of B0 AT1 based on the high-resolution structure of the highly homologous Drosophila dopamine transporter. KEY RESULTS We characterized a series of novel inhibitors of the B0 AT1 transporter. Benztropine was identified as a competitive inhibitor of the transporter showing an IC50 of 44 ± 9 μM. The compound was selective with regard to related transporters and blocked neutral amino acid uptake in inverted sections of mouse intestine. CONCLUSION AND IMPLICATIONS The tools established in this study can be widely used to identify new transport inhibitors. Using these tools, we were able to identify compounds that can be used to study epithelial transport, to induce protein restriction, or be developed further through medicinal chemistry.
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Affiliation(s)
- Qi Cheng
- Research School of Biology, The Australian National University, Canberra, Australia
| | - Nishank Shah
- Research School of Biology, The Australian National University, Canberra, Australia
| | - Angelika Bröer
- Research School of Biology, The Australian National University, Canberra, Australia
| | - Stephen Fairweather
- Research School of Biology, The Australian National University, Canberra, Australia
| | - Yang Jiang
- Research School of Biology, The Australian National University, Canberra, Australia
| | - Dieter Schmoll
- Industriepark Hoechst, Sanofi-Aventis Deutschland GmbH, Frankfurt am Main, Germany
| | - Ben Corry
- Research School of Biology, The Australian National University, Canberra, Australia
| | - Stefan Bröer
- Research School of Biology, The Australian National University, Canberra, Australia
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Freissmuth M, Stockner T, Sucic S. SLC6 Transporter Folding Diseases and Pharmacochaperoning. Handb Exp Pharmacol 2017; 245:249-270. [PMID: 29086036 DOI: 10.1007/164_2017_71] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The human genome encodes 19 genes of the solute carrier 6 (SLC6) family; non-synonymous changes in the coding sequence give rise to mutated transporters, which are misfolded and thus cause diseases in the affected individuals. Prominent examples include mutations in the transporters for dopamine (DAT, SLC6A3), for creatine (CT1, SLC6A8), and for glycine (GlyT2, SLC6A5), which result in infantile dystonia, mental retardation, and hyperekplexia, respectively. Thus, there is an obvious unmet medical need to identify compounds, which can remedy the folding deficit. The pharmacological correction of folding defects was originally explored in mutants of the serotonin transporter (SERT, SLC6A4), which were created to study the COPII-dependent export from the endoplasmic reticulum. This led to the serendipitous discovery of the pharmacochaperoning action of ibogaine. Ibogaine and its metabolite noribogaine also rescue several disease-relevant mutants of DAT. Because the pharmacology of DAT and SERT is exceptionally rich, it is not surprising that additional compounds have been identified, which rescue folding-deficient mutants. These compounds are not only of interest for restoring DAT function in the affected children. They are also likely to serve as useful tools to interrogate the folding trajectory of the transporter. This is likely to initiate a virtuous cycle: if the principles underlying folding of SLC6 transporters are understood, the design of pharmacochaperones ought to be facilitated.
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Affiliation(s)
- Michael Freissmuth
- Institute of Pharmacology and the Gaston H. Glock Research Laboratories for Exploratory Drug Development, Center of Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria.
| | - Thomas Stockner
- Institute of Pharmacology and the Gaston H. Glock Research Laboratories for Exploratory Drug Development, Center of Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Sonja Sucic
- Institute of Pharmacology and the Gaston H. Glock Research Laboratories for Exploratory Drug Development, Center of Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria
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Barar J, Rafi MA, Pourseif MM, Omidi Y. Blood-brain barrier transport machineries and targeted therapy of brain diseases. ACTA ACUST UNITED AC 2016; 6:225-248. [PMID: 28265539 PMCID: PMC5326671 DOI: 10.15171/bi.2016.30] [Citation(s) in RCA: 133] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Revised: 10/02/2016] [Accepted: 10/08/2016] [Indexed: 12/24/2022]
Abstract
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Introduction: Desired clinical outcome of pharmacotherapy of brain diseases largely depends upon the safe drug delivery into the brain parenchyma. However, due to the robust blockade function of the blood-brain barrier (BBB), drug transport into the brain is selectively controlled by the BBB formed by brain capillary endothelial cells and supported by astrocytes and pericytes.
Methods: In the current study, we have reviewed the most recent literature on the subject to provide an insight upon the role and impacts of BBB on brain drug delivery and targeting.
Results: All drugs, either small molecules or macromolecules, designated to treat brain diseases must adequately cross the BBB to provide their therapeutic properties on biological targets within the central nervous system (CNS). However, most of these pharmaceuticals do not sufficiently penetrate into CNS, failing to meet the intended therapeutic outcomes. Most lipophilic drugs capable of penetrating BBB are prone to the efflux functionality of BBB. In contrast, all hydrophilic drugs are facing severe infiltration blockage imposed by the tight cellular junctions of the BBB. Hence, a number of strategies have been devised to improve the efficiency of brain drug delivery and targeted therapy of CNS disorders using multimodal nanosystems (NSs).
Conclusions: In order to improve the therapeutic outcomes of CNS drug transfer and targeted delivery, the discriminatory permeability of BBB needs to be taken under control. The carrier-mediated transport machineries of brain capillary endothelial cells (BCECs) can be exploited for the discovery, development and delivery of small molecules into the brain. Further, the receptor-mediated transport systems can be recruited for the delivery of macromolecular biologics and multimodal NSs into the brain.
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Affiliation(s)
- Jaleh Barar
- Research Center for Pharmaceutical Nanotechnology, Tabriz University of Medical Sciences, Tabriz, Iran ; Department of Pharmaceutics, Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mohammad A Rafi
- Department of Neurology, Sidney Kimmel College of Medicine, Thomas Jefferson University, Philadelphia, PA, USA
| | - Mohammad M Pourseif
- Research Center for Pharmaceutical Nanotechnology, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Yadollah Omidi
- Research Center for Pharmaceutical Nanotechnology, Tabriz University of Medical Sciences, Tabriz, Iran ; Department of Pharmaceutics, Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran
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45
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Gao C, Yang J, Chen M, Yan H, Wang X. Growth curves and age-related changes in carcass characteristics, organs, serum parameters, and intestinal transporter gene expression in domestic pigeon (Columba livia). Poult Sci 2016; 95:867-77. [DOI: 10.3382/ps/pev443] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Accepted: 11/12/2015] [Indexed: 11/20/2022] Open
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Scalise M, Pochini L, Galluccio M, Indiveri C. Glutamine transport. From energy supply to sensing and beyond. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2016; 1857:1147-1157. [PMID: 26951943 DOI: 10.1016/j.bbabio.2016.03.006] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2015] [Revised: 03/01/2016] [Accepted: 03/02/2016] [Indexed: 12/16/2022]
Abstract
Glutamine is the most abundant amino acid in plasma and is actively involved in many biosynthetic and regulatory processes. It can be synthesized endogenously but becomes "conditionally essential" in physiological or pathological conditions of high proliferation rate. To accomplish its functions glutamine has to be absorbed and distributed in the whole body. This job is efficiently carried out by a network of membrane transporters that differ in transport mechanisms and energetics, belonging to families SLC1, 6, 7, 38, and possibly, 25. Some of the transporters are involved in glutamine traffic across different membranes for metabolic purposes; others are involved in specific signaling functions through mTOR. Structure/function relationships and regulatory aspects of glutamine transporters are still at infancy. In the while, insights in involvement of these transporters in cell redox control, cancer metabolism and drug interactions are arising, stimulating basic research to uncover molecular mechanisms of transport and regulation. This article is part of a Special Issue entitled 'EBEC 2016: 19th European Bioenergetics Conference, Riva del Garda, Italy, July 2-6, 2016', edited by Prof. Paolo Bernardi.
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Affiliation(s)
- Mariafrancesca Scalise
- Department DiBEST (Biologia, Ecologia, Scienze della Terra) Unit of Biochemistry and Molecular Biotechnology, University of Calabria, Via P. Bucci 4C, 87036 Arcavacata di Rende, Italy
| | - Lorena Pochini
- Department DiBEST (Biologia, Ecologia, Scienze della Terra) Unit of Biochemistry and Molecular Biotechnology, University of Calabria, Via P. Bucci 4C, 87036 Arcavacata di Rende, Italy
| | - Michele Galluccio
- Department DiBEST (Biologia, Ecologia, Scienze della Terra) Unit of Biochemistry and Molecular Biotechnology, University of Calabria, Via P. Bucci 4C, 87036 Arcavacata di Rende, Italy
| | - Cesare Indiveri
- Department DiBEST (Biologia, Ecologia, Scienze della Terra) Unit of Biochemistry and Molecular Biotechnology, University of Calabria, Via P. Bucci 4C, 87036 Arcavacata di Rende, Italy.
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Komaba S, Coluccio LM. Myosin 1b Regulates Amino Acid Transport by Associating Transporters with the Apical Plasma Membrane of Kidney Cells. PLoS One 2015; 10:e0138012. [PMID: 26361046 PMCID: PMC4567078 DOI: 10.1371/journal.pone.0138012] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2015] [Accepted: 08/24/2015] [Indexed: 01/11/2023] Open
Abstract
Amino acid transporters (AATers) in the brush border of the apical plasma membrane (APM) of renal proximal tubule (PT) cells mediate amino acid transport (AAT). We found that the membrane-associated class I myosin myosin 1b (Myo1b) localized at the apical brush border membrane of PTs. In opossum kidney (OK) 3B/2 epithelial cells, which are derived from PTs, expressed rat Myo1b-GFP colocalized in patched microvilli with expressed mouse V5-tagged SIT1 (SIT1-V5), which mediates neutral amino acid transport in OK cells. Lentivirus-mediated delivery of opossum Myo1b-specific shRNA resulted in knockdown (kd) of Myo1b expression, less SIT1-V5 at the APM as determined by localization studies, and a decrease in neutral AAT as determined by radioactive uptake assays. Myo1b kd had no effect on Pi transport or noticeable change in microvilli structure as determined by rhodamine phalloidin staining. The studies are the first to define a physiological role for Myo1b, that of regulating renal AAT by modulating the association of AATers with the APM.
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Affiliation(s)
- Shigeru Komaba
- Department of Physiology & Biophysics, Boston University School of Medicine, Boston, Massachusetts, United States of America
| | - Lynne M. Coluccio
- Department of Physiology & Biophysics, Boston University School of Medicine, Boston, Massachusetts, United States of America
- * E-mail:
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48
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Jiang Y, Rose AJ, Sijmonsma TP, Bröer A, Pfenninger A, Herzig S, Schmoll D, Bröer S. Mice lacking neutral amino acid transporter B(0)AT1 (Slc6a19) have elevated levels of FGF21 and GLP-1 and improved glycaemic control. Mol Metab 2015; 4:406-17. [PMID: 25973388 PMCID: PMC4421019 DOI: 10.1016/j.molmet.2015.02.003] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Revised: 02/05/2015] [Accepted: 02/09/2015] [Indexed: 02/07/2023] Open
Abstract
OBJECTIVE Type 2 diabetes arises from insulin resistance of peripheral tissues followed by dysfunction of β-cells in the pancreas due to metabolic stress. Both depletion and supplementation of neutral amino acids have been discussed as strategies to improve insulin sensitivity. Here we characterise mice lacking the intestinal and renal neutral amino acid transporter B(0)AT1 (Slc6a19) as a model to study the consequences of selective depletion of neutral amino acids. METHODS Metabolic tests, analysis of metabolite levels and signalling pathways were used to characterise mice lacking the intestinal and renal neutral amino acid transporter B(0)AT1 (Slc6a19). RESULTS Reduced uptake of neutral amino acids in the intestine and loss of neutral amino acids in the urine causes an overload of amino acids in the lumen of the intestine and reduced systemic amino acid availability. As a result, higher levels of glucagon-like peptide 1 (GLP-1) are produced by the intestine after a meal, while the liver releases the starvation hormone fibroblast growth factor 21 (FGF21). The combination of these hormones generates a metabolic phenotype that is characterised by efficient removal of glucose, particularly by the heart, reduced adipose tissue mass, browning of subcutaneous white adipose tissue, enhanced production of ketone bodies and reduced hepatic glucose output. CONCLUSIONS Reduced neutral amino acid availability improves glycaemic control. The epithelial neutral amino acid transporter B(0)AT1 could be a suitable target to treat type 2 diabetes.
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Affiliation(s)
- Yang Jiang
- Research School of Biology, The Australian National University, Canberra, ACT 0200, Australia
| | - Adam J. Rose
- Joint Research Division Molecular Metabolic Control, German Cancer Research Center, Center for Molecular Biology, Heidelberg University and Heidelberg University Hospital, 69120 Heidelberg, Germany
| | - Tjeerd P. Sijmonsma
- Joint Research Division Molecular Metabolic Control, German Cancer Research Center, Center for Molecular Biology, Heidelberg University and Heidelberg University Hospital, 69120 Heidelberg, Germany
| | - Angelika Bröer
- Research School of Biology, The Australian National University, Canberra, ACT 0200, Australia
| | - Anja Pfenninger
- Sanofi-Aventis Deutschland GmbH, Industriepark Hoechst, Frankfurt am Main 65926, Germany
| | - Stephan Herzig
- Joint Research Division Molecular Metabolic Control, German Cancer Research Center, Center for Molecular Biology, Heidelberg University and Heidelberg University Hospital, 69120 Heidelberg, Germany
| | - Dieter Schmoll
- Sanofi-Aventis Deutschland GmbH, Industriepark Hoechst, Frankfurt am Main 65926, Germany
| | - Stefan Bröer
- Research School of Biology, The Australian National University, Canberra, ACT 0200, Australia
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Synthesis and evaluation of 2-amino-5-(4-[18F]fluorophenyl)pent-4-ynoic acid ([18F]FPhPA): A novel 18F-labeled amino acid for oncologic PET imaging. Nucl Med Biol 2014; 41:660-9. [DOI: 10.1016/j.nucmedbio.2014.05.140] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Revised: 05/24/2014] [Accepted: 05/27/2014] [Indexed: 11/20/2022]
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50
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Pochini L, Scalise M, Galluccio M, Indiveri C. Membrane transporters for the special amino acid glutamine: structure/function relationships and relevance to human health. Front Chem 2014; 2:61. [PMID: 25157349 PMCID: PMC4127817 DOI: 10.3389/fchem.2014.00061] [Citation(s) in RCA: 175] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Accepted: 07/16/2014] [Indexed: 12/26/2022] Open
Abstract
Glutamine together with glucose is essential for body's homeostasis. It is the most abundant amino acid and is involved in many biosynthetic, regulatory and energy production processes. Several membrane transporters which differ in transport modes, ensure glutamine homeostasis by coordinating its absorption, reabsorption and delivery to tissues. These transporters belong to different protein families, are redundant and ubiquitous. Their classification, originally based on functional properties, has recently been associated with the SLC nomenclature. Function of glutamine transporters is studied in cells over-expressing the transporters or, more recently in proteoliposomes harboring the proteins extracted from animal tissues or over-expressed in microorganisms. The role of the glutamine transporters is linked to their transport modes and coupling with Na+ and H+. Most transporters share specificity for other neutral or cationic amino acids. Na+-dependent co-transporters efficiently accumulate glutamine while antiporters regulate the pools of glutamine and other amino acids. The most acknowledged glutamine transporters belong to the SLC1, 6, 7, and 38 families. The members involved in the homeostasis are the co-transporters B0AT1 and the SNAT members 1, 2, 3, 5, and 7; the antiporters ASCT2, LAT1 and 2. The last two are associated to the ancillary CD98 protein. Some information on regulation of the glutamine transporters exist, which, however, need to be deepened. No information at all is available on structures, besides some homology models obtained using similar bacterial transporters as templates. Some models of rat and human glutamine transporters highlight very similar structures between the orthologs. Moreover the presence of glycosylation and/or phosphorylation sites located at the extracellular or intracellular faces has been predicted. ASCT2 and LAT1 are over-expressed in several cancers, thus representing potential targets for pharmacological intervention.
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Affiliation(s)
- Lorena Pochini
- Department DiBEST (Biologia, Ecologia, Scienze della Terra) Unit of Biochemistry and Molecular Biotechnology, University of Calabria Arcavacata di Rende, Italy
| | - Mariafrancesca Scalise
- Department DiBEST (Biologia, Ecologia, Scienze della Terra) Unit of Biochemistry and Molecular Biotechnology, University of Calabria Arcavacata di Rende, Italy
| | - Michele Galluccio
- Department DiBEST (Biologia, Ecologia, Scienze della Terra) Unit of Biochemistry and Molecular Biotechnology, University of Calabria Arcavacata di Rende, Italy
| | - Cesare Indiveri
- Department DiBEST (Biologia, Ecologia, Scienze della Terra) Unit of Biochemistry and Molecular Biotechnology, University of Calabria Arcavacata di Rende, Italy
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