1
|
Tanpaiboon P, Huang Y, Louie JZ, Sharma R, Cederbaum S, Salazar D. Plasma arginine levels in arginase deficiency in the "real world". Mol Genet Metab Rep 2024; 38:101042. [PMID: 38221915 PMCID: PMC10787283 DOI: 10.1016/j.ymgmr.2023.101042] [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: 11/01/2023] [Revised: 12/12/2023] [Accepted: 12/18/2023] [Indexed: 01/16/2024] Open
Abstract
Background Deficiency of arginase-1, the final enzyme in the urea cycle, causes a distinct clinical syndrome and is characterized biochemically by a high level of plasma arginine. While conventional therapy for urea cycle disorders can lower these levels to some extent, it does not normalize them. Until now, research on plasma arginine levels in this disorder has primarily relied on data from specialized tertiary centers, which limits the ability to assess the natural history and treatment efficacy of arginase-1 deficiency due to the small number of patients in each center and technical variations in plasma arginine measurements among different laboratories. Method In this study, we reported plasma arginine levels from 51 patients with arginase-1 deficiency in the database of Quest Diagnostics. The samples were collected from different US regions. Results The mean plasma arginine level in these treated patients was 373 μmol/L and the median level was 368.4 μmol/L. Our data set from 30 arginase deficiency patients with plasma amino acid data from five or more collections revealed significant correlations between the levels of arginine and five other amino acids (citrulline, alanine, ornithine, glutamine, and asparagine). Conclusion Despite treatment, the arginine levels remained persistently elevated and did not change significantly with age, suggesting the current treatment regimen is inadequate to control arginine levels and underscoring the need to seek more effective treatments for this disorder.
Collapse
Affiliation(s)
- Pranoot Tanpaiboon
- Biochemical Genetics, R&D Molecular Genetics & Oncology, Quest Diagnostics Nichols Institute, San Juan Capistrano, CA 92675, United States of America
| | - Yue Huang
- Division of Clinical Genetics, Department of Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, United States of America
| | - Judy Z. Louie
- Biochemical Genetics, R&D Molecular Genetics & Oncology, Quest Diagnostics Nichols Institute, San Juan Capistrano, CA 92675, United States of America
| | - Rajesh Sharma
- Ex-employee Quest Diagnostics Nichols Institute, San Juan Capistrano, CA 92675, United States of America
| | - Stephen Cederbaum
- Division of Clinical Genetics, Department of Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, United States of America
- Departments of Psychiatry, Pediatrics and Human Genetics and the Intellectual and Developmental Disabilities Research Center, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, United States of America
| | - Denise Salazar
- Biochemical Genetics, R&D Molecular Genetics & Oncology, Quest Diagnostics Nichols Institute, San Juan Capistrano, CA 92675, United States of America
| |
Collapse
|
2
|
Hua Y, Huang W, Wang F, Jing Z, Li J, Wang Q, Zhao Y. Metabolites, gene expression, and gut microbiota profiles suggest the putative mechanisms via which dietary creatine increases the serum taurine and g-ABA contents in Megalobrama amblycephala. FISH PHYSIOLOGY AND BIOCHEMISTRY 2023; 49:253-274. [PMID: 36897433 DOI: 10.1007/s10695-023-01177-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Accepted: 03/01/2023] [Indexed: 05/04/2023]
Abstract
A 90-day experiment was conducted to explore the effects of creatine on growth performance, liver health status, metabolites, and gut microbiota in Megalobrama amblycephala. There were 6 treatments as follows: control (CD, 29.41% carbohydrates), high carbohydrate (HCD, 38.14% carbohydrates), betaine (BET, 1.2% betaine + 39.76% carbohydrates), creatine 1 (CRE1, 0.5% creatine + 1.2% betaine + 39.29% carbohydrates), creatine 2 (CRE2, 1% creatine + 1.2% betaine + 39.50% carbohydrates), and creatine 3 (CRE3, 2% creatine + 1.2% betaine + 39.44% carbohydrates). The results showed that supplementing creatine and betaine together reduced the feed conversion ratio significantly (P < 0.05, compared to CD and HCD) and improved liver health (compared to HCD). Compared with the BET group, dietary creatine significantly increased the abundances of Firmicutes, Bacteroidota, ZOR0006, and Bacteroides and decreased the abundances of Proteobacteria, Fusobacteriota, Vibrio, Crenobacter, and Shewanella in the CRE1 group. Dietary creatine increased the content of taurine, arginine, ornithine, γ-aminobutyric acid (g-ABA), and creatine (CRE1 vs. BET group) and the expression of creatine kinase (ck), sulfinoalanine decarboxylase (csad), guanidinoacetate N-methyltransferase (gamt), glycine amidinotransferase (gatm), agmatinase (agmat), diamine oxidase1 (aoc1), and glutamate decarboxylase (gad) in the CRE1 group. Overall, these results suggested that dietary supplementation of creatine (0.5-2%) did not affect the growth performance, but it altered the gut microbial composition at the phylum and genus levels, which might be beneficial to the gut health of M. amblycephala; dietary creatine also increased the serum content of taurine by enhancing the expressions of ck and csad and increased the serum content of g-ABA by enhancing the arginine content and the expressions of gatm, agmat, gad, and aoc1.
Collapse
Affiliation(s)
- Yizhuo Hua
- College of Fisheries, Huazhong Agricultural University, Wuhan, 430070, China
- Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Wuhan, 430070, China
- Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Wuhan, 430070, China
- Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan, 430070, China
| | - Wangwang Huang
- College of Fisheries, Huazhong Agricultural University, Wuhan, 430070, China
- Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Wuhan, 430070, China
- Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Wuhan, 430070, China
- Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan, 430070, China
| | - Fan Wang
- College of Fisheries, Huazhong Agricultural University, Wuhan, 430070, China
- Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Wuhan, 430070, China
- Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Wuhan, 430070, China
- Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan, 430070, China
| | - Zhao Jing
- College of Fisheries, Huazhong Agricultural University, Wuhan, 430070, China
- Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Wuhan, 430070, China
- Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Wuhan, 430070, China
- Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan, 430070, China
| | - Juntao Li
- Institute of Tropical Bioscience and Biotechnology, Haikou, 570102, China
| | - Qingchao Wang
- College of Fisheries, Huazhong Agricultural University, Wuhan, 430070, China
- Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Wuhan, 430070, China
- Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Wuhan, 430070, China
- Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan, 430070, China
| | - Yuhua Zhao
- College of Fisheries, Huazhong Agricultural University, Wuhan, 430070, China.
- Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Wuhan, 430070, China.
- Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Wuhan, 430070, China.
- Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan, 430070, China.
| |
Collapse
|
3
|
Boffa I, Polishchuk E, De Stefano L, Dell'Aquila F, Nusco E, Marrocco E, Audano M, Pedretti S, Caterino M, Bellezza I, Ruoppolo M, Mitro N, Cellini B, Auricchio A, Brunetti-Pierri N. Liver-directed gene therapy for ornithine aminotransferase deficiency. EMBO Mol Med 2023; 15:e17033. [PMID: 36647689 PMCID: PMC10086579 DOI: 10.15252/emmm.202217033] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 12/16/2022] [Accepted: 12/19/2022] [Indexed: 01/18/2023] Open
Abstract
Gyrate atrophy of choroid and retina (GACR) is a chorioretinal degeneration caused by pathogenic variants in the gene encoding ornithine aminotransferase (OAT), an enzyme mainly expressed in liver. Affected patients have increased ornithine concentrations in blood and other body fluids and develop progressive constriction of vision fields leading to blindness. Current therapies are unsatisfactory and better treatments are highly needed. In two mouse models of OAT deficiency that recapitulates biochemical and retinal changes of GACR, we investigated the efficacy of an intravenously injected serotype 8 adeno-associated (AAV8) vector expressing OAT under the control of a hepatocyte-specific promoter. Following injections, OAT-deficient mice showed reductions of ornithine concentrations in blood and eye cups compared with control mice injected with a vector expressing green fluorescent protein. AAV-injected mice showed improved electroretinogram response and partial restoration of retinal structure up to one-year post-injection. In summary, hepatic OAT expression by AAV8 vector was effective at correction of hyperornithinemia and improved function and structure of the retina. In conclusion, this study provides proof-of-concept of efficacy of liver-directed AAV-mediated gene therapy of GACR.
Collapse
Affiliation(s)
- Iolanda Boffa
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy
| | - Elena Polishchuk
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy
| | - Lucia De Stefano
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy
| | - Fabio Dell'Aquila
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy
| | - Edoardo Nusco
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy
| | - Elena Marrocco
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy
| | - Matteo Audano
- Department of Pharmacology and Biomolecular Sciences, University of Milan, Milan, Italy
| | - Silvia Pedretti
- Department of Pharmacology and Biomolecular Sciences, University of Milan, Milan, Italy
| | - Marianna Caterino
- Department of Molecular Medicine and Medical Biotechnology, University of Naples "Federico II", Naples, Italy.,CEINGE - Biotecnologie Avanzate s.c.a.r.l., Naples, Italy
| | - Ilaria Bellezza
- Department of Experimental Medicine, Section of Physiology and Biochemistry, University of Perugia, Perugia, Italy
| | - Margherita Ruoppolo
- Department of Molecular Medicine and Medical Biotechnology, University of Naples "Federico II", Naples, Italy.,CEINGE - Biotecnologie Avanzate s.c.a.r.l., Naples, Italy
| | - Nico Mitro
- Department of Pharmacology and Biomolecular Sciences, University of Milan, Milan, Italy.,Department of Experimental Oncology, IEO, European Institute of Oncology IRCCS, Milan, Italy
| | - Barbara Cellini
- Department of Experimental Medicine, Section of Physiology and Biochemistry, University of Perugia, Perugia, Italy
| | - Alberto Auricchio
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy.,Department of Advanced Biomedical Sciences, "Federico II" University, Naples, Italy
| | - Nicola Brunetti-Pierri
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy.,Department of Translational Medicine, "Federico II" University, Naples, Italy.,Scuola Superiore Meridionale (SSM, School of Advanced Studies), Genomics and Experimental Medicine Program, University of Naples Federico II, Naples, Italy
| |
Collapse
|
4
|
Preclinical Models of Retinitis Pigmentosa. Methods Mol Biol 2022; 2560:181-215. [PMID: 36481897 DOI: 10.1007/978-1-0716-2651-1_19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Retinitis pigmentosa (RP) is the name for a group of phenotypically-related heritable retinal degenerative disorders. Many genes have been implicated as causing variants of RP, and while the clinical phenotypes are remarkably similar, they may differ in age of onset, progression, and severity. Common inheritance patterns for specific genes connected with the development of the disorder include autosomal dominant, autosomal recessive, and X-linked. Modeling the disease in animals and other preclinical systems offers a cost-conscious, ethical, and time-efficient method for studying the disease subtypes. The history of RP models is briefly examined, and both naturally occurring and transgenic preclinical models of RP in many different organisms are discussed. Syndromic forms of RP and models thereof are reviewed as well.
Collapse
|
5
|
Butrin A, Butrin A, Wawrzak Z, Moran GR, Liu D. Determination of the pH dependence, substrate specificity, and turnovers of alternative substrates for human ornithine aminotransferase. J Biol Chem 2022; 298:101969. [PMID: 35460691 PMCID: PMC9136103 DOI: 10.1016/j.jbc.2022.101969] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Revised: 04/17/2022] [Accepted: 04/19/2022] [Indexed: 01/08/2023] Open
Abstract
Hepatocellular carcinoma (HCC) is the most common primary cancer of the liver and occurs predominantly in patients with underlying chronic liver diseases. Over the past decade, human ornithine aminotransferase (hOAT), which is an enzyme that catalyzes the metabolic conversion of ornithine into an intermediate for proline or glutamate synthesis, has been found to be overexpressed in HCC cells. hOAT has since emerged as a promising target for novel anticancer therapies, especially for the ongoing rational design effort to discover mechanism-based inactivators (MBIs). Despite the significance of hOAT in human metabolism and its clinical potential as a drug target against HCC, there are significant knowledge deficits with regard to its catalytic mechanism and structural characteristics. Ongoing MBI design efforts require in-depth knowledge of the enzyme active site, in particular, pKa values of potential nucleophiles and residues necessary for the molecular recognition of ligands. Here, we conducted a study detailing the fundamental active-site properties of hOAT using stopped-flow spectrophotometry and X-ray crystallography. Our results quantitatively revealed the pH dependence of the multistep reaction mechanism and illuminated the roles of ornithine α-amino and δ-amino groups in substrate recognition and in facilitating catalytic turnover. These findings provided insights of the catalytic mechanism that could benefit the rational design of MBIs against hOAT. In addition, substrate recognition and turnover of several fragment-sized alternative substrates of hOATs, which could serve as structural templates for MBI design, were also elucidated.
Collapse
Affiliation(s)
- Arseniy Butrin
- Department of Chemistry and Biochemistry, Loyola University Chicago, Chicago, Illinois, USA
| | - Anastassiya Butrin
- Department of Chemistry and Biochemistry, Loyola University Chicago, Chicago, Illinois, USA
| | - Zdzislaw Wawrzak
- Synchrotron Research Center, Life Sciences Collaborative Access Team, Northwestern University, Argonne, Illinois, USA
| | - Graham R Moran
- Department of Chemistry and Biochemistry, Loyola University Chicago, Chicago, Illinois, USA.
| | - Dali Liu
- Department of Chemistry and Biochemistry, Loyola University Chicago, Chicago, Illinois, USA.
| |
Collapse
|
6
|
Kaczmarczyk A, Baker M, Diddle J, Yuzyuk T, Valle D, Lindstrom K. A neonate with ornithine aminotransferase deficiency; insights on the hyperammonemia-associated biochemical phenotype of gyrate atrophy. Mol Genet Metab Rep 2022; 31:100857. [PMID: 35782604 PMCID: PMC9248225 DOI: 10.1016/j.ymgmr.2022.100857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 02/26/2022] [Accepted: 02/27/2022] [Indexed: 11/29/2022] Open
Affiliation(s)
- Aneta Kaczmarczyk
- Department of Pathology, University of Utah, Salt Lake City, UT, USA
- ARUP Institute for Clinical and Experimental Pathology®, Salt Lake City, UT, USA
- Corresponding author at: ARUP Laboratories, 500 Chipeta Way, MS115, Salt Lake City, UT 84108, USA.
| | - Mark Baker
- Phoenix Children's Pediatric Residency Program Alliance, Phoenix Children's Hospital, Phoenix, AZ, USA
| | - Julianna Diddle
- Phoenix Children's Pediatric Residency Program Alliance, Phoenix Children's Hospital, Phoenix, AZ, USA
| | - Tatiana Yuzyuk
- Department of Pathology, University of Utah, Salt Lake City, UT, USA
- ARUP Institute for Clinical and Experimental Pathology®, Salt Lake City, UT, USA
| | - David Valle
- McKusick-Nathans Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Kristin Lindstrom
- Division of Genetics and Metabolism, Phoenix Children's Hospital, Phoenix, AZ, USA
| |
Collapse
|
7
|
Kanninen T, Bryant E, Koerner C, Gonik B. First reported case of pregnancy in a patient with ornithine aminotransferase deficiency. Nutrition 2021; 93:111513. [PMID: 34768032 DOI: 10.1016/j.nut.2021.111513] [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: 04/29/2021] [Revised: 09/17/2021] [Accepted: 10/03/2021] [Indexed: 11/29/2022]
Abstract
Ornithine aminotransferase deficiency is a rare autosomalrecessive human inborn error of the metabolism resulting in hyperornithinemia and progressive chorioretinal degeneration (gyrate atrophy) with blindness. There are few reports in the literature and none, to our knowledge, that address this condition during pregnancy. We report on a novel case of ornithine aminotransferase deficiency during pregnancy that was managed actively with arginine and protein restriction with serial amino acid and fetal growth monitoring, resulting in an uncomplicated term live birth.
Collapse
Affiliation(s)
- Tomi Kanninen
- Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Wayne State University School of Medicine, Detroit, Michigan, USA
| | - Elizabeth Bryant
- Department of Obstetrics and Gynecology, Huron Valley-Sinai Hospital, Commerce, Michigan, USA
| | - Celide Koerner
- Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Bernard Gonik
- Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Wayne State University School of Medicine, Detroit, Michigan, USA.
| |
Collapse
|
8
|
Zárybnický T, Heikkinen A, Kangas SM, Karikoski M, Martínez-Nieto GA, Salo MH, Uusimaa J, Vuolteenaho R, Hinttala R, Sipilä P, Kuure S. Modeling Rare Human Disorders in Mice: The Finnish Disease Heritage. Cells 2021; 10:cells10113158. [PMID: 34831381 PMCID: PMC8621025 DOI: 10.3390/cells10113158] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 11/04/2021] [Accepted: 11/06/2021] [Indexed: 12/31/2022] Open
Abstract
The modification of genes in animal models has evidently and comprehensively improved our knowledge on proteins and signaling pathways in human physiology and pathology. In this review, we discuss almost 40 monogenic rare diseases that are enriched in the Finnish population and defined as the Finnish disease heritage (FDH). We will highlight how gene-modified mouse models have greatly facilitated the understanding of the pathological manifestations of these diseases and how some of the diseases still lack proper models. We urge the establishment of subsequent international consortiums to cooperatively plan and carry out future human disease modeling strategies. Detailed information on disease mechanisms brings along broader understanding of the molecular pathways they act along both parallel and transverse to the proteins affected in rare diseases, therefore also aiding understanding of common disease pathologies.
Collapse
Affiliation(s)
- Tomáš Zárybnický
- Stem Cells and Metabolism Research Program, Faculty of Medicine, University of Helsinki, P.O. Box 63, 00014 Helsinki, Finland;
| | - Anne Heikkinen
- Biocenter Oulu, University of Oulu, P.O. Box 5000, 90014 Oulu, Finland; (A.H.); (S.M.K.); (M.H.S.); (R.V.)
- Oulu Center for Cell-Matrix Research, Faculty of Biochemistry and Molecular Medicine, University of Oulu, P.O. Box 8000, 90014 Oulu, Finland
| | - Salla M. Kangas
- Biocenter Oulu, University of Oulu, P.O. Box 5000, 90014 Oulu, Finland; (A.H.); (S.M.K.); (M.H.S.); (R.V.)
- PEDEGO Research Unit, University of Oulu, P.O. Box 8000, 90014 Oulu, Finland;
- Medical Research Center, Oulu University Hospital, University of Oulu, P.O. Box 5000, 90014 Oulu, Finland
| | - Marika Karikoski
- Research Centre for Integrative Physiology and Pharmacology, Institute of Biomedicine, University of Turku, 20520 Turku, Finland; (M.K.); (G.A.M.-N.)
| | - Guillermo Antonio Martínez-Nieto
- Research Centre for Integrative Physiology and Pharmacology, Institute of Biomedicine, University of Turku, 20520 Turku, Finland; (M.K.); (G.A.M.-N.)
- Turku Center for Disease Modelling (TCDM), Institute of Biomedicine, University of Turku, 20520 Turku, Finland
| | - Miia H. Salo
- Biocenter Oulu, University of Oulu, P.O. Box 5000, 90014 Oulu, Finland; (A.H.); (S.M.K.); (M.H.S.); (R.V.)
- PEDEGO Research Unit, University of Oulu, P.O. Box 8000, 90014 Oulu, Finland;
- Medical Research Center, Oulu University Hospital, University of Oulu, P.O. Box 5000, 90014 Oulu, Finland
| | - Johanna Uusimaa
- PEDEGO Research Unit, University of Oulu, P.O. Box 8000, 90014 Oulu, Finland;
- Medical Research Center, Oulu University Hospital, University of Oulu, P.O. Box 5000, 90014 Oulu, Finland
- Clinic for Children and Adolescents, Division of Pediatric Neurology, Oulu University Hospital, P.O. Box 20, 90029 Oulu, Finland
| | - Reetta Vuolteenaho
- Biocenter Oulu, University of Oulu, P.O. Box 5000, 90014 Oulu, Finland; (A.H.); (S.M.K.); (M.H.S.); (R.V.)
| | - Reetta Hinttala
- Biocenter Oulu, University of Oulu, P.O. Box 5000, 90014 Oulu, Finland; (A.H.); (S.M.K.); (M.H.S.); (R.V.)
- PEDEGO Research Unit, University of Oulu, P.O. Box 8000, 90014 Oulu, Finland;
- Medical Research Center, Oulu University Hospital, University of Oulu, P.O. Box 5000, 90014 Oulu, Finland
- Correspondence: (R.H.); (P.S.); (S.K.)
| | - Petra Sipilä
- Research Centre for Integrative Physiology and Pharmacology, Institute of Biomedicine, University of Turku, 20520 Turku, Finland; (M.K.); (G.A.M.-N.)
- Turku Center for Disease Modelling (TCDM), Institute of Biomedicine, University of Turku, 20520 Turku, Finland
- Correspondence: (R.H.); (P.S.); (S.K.)
| | - Satu Kuure
- Stem Cells and Metabolism Research Program, Faculty of Medicine, University of Helsinki, P.O. Box 63, 00014 Helsinki, Finland;
- GM-Unit, Laboratory Animal Center, Helsinki Institute of Life Science, University of Helsinki, 00790 Helsinki, Finland
- Correspondence: (R.H.); (P.S.); (S.K.)
| |
Collapse
|
9
|
Nolan ND, Quinn PMJ, Tsang SH. Overcoming translational barriers in modeling macular degenerations. Cell Stem Cell 2021; 28:781-783. [PMID: 33961756 DOI: 10.1016/j.stem.2021.04.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Advances in tissue mimetics are paving the way for interrogating both the pathobiology of human disease and innovative therapeutic paradigms. In this issue of Cell Stem Cell, Manian et al. (2021) develop a novel iPSC-derived retinal pigment epithelium (RPE)-choriocapillaris (CC) complex that recapitulates key features of macular degenerations.
Collapse
Affiliation(s)
- Nicholas David Nolan
- Jonas Children's Vision Care, Department of Ophthalmology, New York-Presbyterian Hospital, New York, NY, USA; Department of Biomedical Engineering, Columbia University, New York, NY, USA
| | - Peter M J Quinn
- Jonas Children's Vision Care, Department of Ophthalmology, New York-Presbyterian Hospital, New York, NY, USA
| | - Stephen H Tsang
- Jonas Children's Vision Care, Department of Ophthalmology, New York-Presbyterian Hospital, New York, NY, USA; Department of Pathology & Cell Biology, Institute of Human Nutrition, and Columbia Stem Cell Initiative, New York, NY, USA.
| |
Collapse
|
10
|
Du J, Zhu S, Lim RR, Chao JR. Proline metabolism and transport in retinal health and disease. Amino Acids 2021; 53:1789-1806. [PMID: 33871679 PMCID: PMC8054134 DOI: 10.1007/s00726-021-02981-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Accepted: 04/10/2021] [Indexed: 12/11/2022]
Abstract
The retina is one of the most energy-demanding tissues in the human body. Photoreceptors in the outer retina rely on nutrient support from the neighboring retinal pigment epithelium (RPE), a monolayer of epithelial cells that separate the retina and choroidal blood supply. RPE dysfunction or cell death can result in photoreceptor degeneration, leading to blindness in retinal degenerative diseases including some inherited retinal degenerations and age-related macular degeneration (AMD). In addition to having ready access to rich nutrients from blood, the RPE is also supplied with lactate from adjacent photoreceptors. Moreover, RPE can phagocytose lipid-rich outer segments for degradation and recycling on a daily basis. Recent studies show RPE cells prefer proline as a major metabolic substrate, and they are highly enriched for the proline transporter, SLC6A20. In contrast, dysfunctional or poorly differentiated RPE fails to utilize proline. RPE uses proline to fuel mitochondrial metabolism, synthesize amino acids, build the extracellular matrix, fight against oxidative stress, and sustain differentiation. Remarkably, the neural retina rarely imports proline directly, but it uptakes and utilizes intermediates and amino acids derived from proline catabolism in the RPE. Mutations of genes in proline metabolism are associated with retinal degenerative diseases, and proline supplementation is reported to improve RPE-initiated vision loss. This review will cover proline metabolism in RPE and highlight the importance of proline transport and utilization in maintaining retinal metabolism and health.
Collapse
Affiliation(s)
- Jianhai Du
- Department of Ophthalmology and Visual Sciences, West Virginia University, Morgantown, WV, 26506, USA. .,Department of Biochemistry, West Virginia University, Morgantown, WV, 26506, USA. .,One Medical Center Dr, WVU Eye Institute, PO Box 9193, Morgantown, WV, 26505, USA.
| | - Siyan Zhu
- Department of Ophthalmology and Visual Sciences, West Virginia University, Morgantown, WV, 26506, USA.,Department of Biochemistry, West Virginia University, Morgantown, WV, 26506, USA
| | - Rayne R Lim
- Department of Ophthalmology, University of Washington, Seattle, WA, 98109, USA
| | - Jennifer R Chao
- Department of Ophthalmology, University of Washington, Seattle, WA, 98109, USA
| |
Collapse
|
11
|
Montioli R, Bellezza I, Desbats MA, Borri Voltattorni C, Salviati L, Cellini B. Deficit of human ornithine aminotransferase in gyrate atrophy: Molecular, cellular, and clinical aspects. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2020; 1869:140555. [PMID: 33068755 DOI: 10.1016/j.bbapap.2020.140555] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 10/09/2020] [Accepted: 10/12/2020] [Indexed: 02/06/2023]
Abstract
Gyrate Atrophy (GA) of the choroid and retina (MIM# 258870) is an autosomal recessive disorder due to mutations of the OAT gene encoding ornithine-delta-aminotransferase (OAT), associated with progressive retinal deterioration and blindness. The disease has a theoretical global incidence of approximately 1:1,500,000. OAT is mainly involved in ornithine catabolism in adults, thus explaining the hyperornithinemia as hallmark of the disease. Patients are treated with an arginine-restricted diet, to limit ornithine load, or the administration of Vitamin B6, a precursor of the OAT coenzyme pyridoxal phosphate. Although the clinical and genetic aspects of GA are known for many years, the enzymatic phenotype of pathogenic variants and their response to Vitamin B6, as well as the molecular mechanisms explaining retinal damage, are poorly clarified. Herein, we provide an overview of the current knowledge on the biochemical properties of human OAT and on the molecular, cellular, and clinical aspects of GA.
Collapse
Affiliation(s)
- Riccardo Montioli
- Department of Neurosciences, Biomedicine and Movement Sciences, Section of Biological Chemistry, University of Verona, Verona, Italy
| | - Ilaria Bellezza
- Department of Experimental Medicine, Section of Physiology and Biochemistry, University of Perugia, Perugia, Italy
| | - Maria Andrea Desbats
- Clinical Genetics Unit, Department of Woman and Child Health, University of Padova, Padova, Italy
| | - Carla Borri Voltattorni
- Department of Neurosciences, Biomedicine and Movement Sciences, Section of Biological Chemistry, University of Verona, Verona, Italy
| | - Leonardo Salviati
- Clinical Genetics Unit, Department of Woman and Child Health, University of Padova, Padova, Italy.
| | - Barbara Cellini
- Department of Experimental Medicine, Section of Physiology and Biochemistry, University of Perugia, Perugia, Italy.
| |
Collapse
|
12
|
Metabolism and Functions of Amino Acids in Sense Organs. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1265:201-217. [PMID: 32761578 DOI: 10.1007/978-3-030-45328-2_12] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Sense organs (eyes, ears, nose, tongue, and skin) provide senses of sight, hearing, smell, taste, and touch, respectively, to aid the survival, development, learning, and adaptation of humans and other animals (including fish). Amino acids (AAs) play an important role in the growth, development, and functions of the sense organs. Recent work has identified receptor-mediated mechanisms responsible for the chemosensory transduction of five basic taste qualities (sweet, sour, bitter, umami and salty tastes). Abnormal metabolism of AAs result in a structural deformity of tissues and their dysfunction. To date, there is a large database for AA metabolism in the eye and skin under normal (e.g., developmental changes and physiological responses) and pathological (e.g., nutritional and metabolic diseases, nutrient deficiency, infections, and cancer) conditions. Important metabolites of AAs include nitric oxide and polyamines (from arginine), melanin and dopamine (from phenylalanine and tyrosine), and serotonin and melatonin (from tryptophan) in both the eye and the skin; γ-aminobutyrate (from glutamate) in the retina; and urocanic acid and histamine (from histidine) in the skin. At present, relatively little is known about the synthesis or catabolism of AAs in the ears, nose, and tongue. Future research should be directed to: (1) address this issue with regard to healthy ageing, nasal and sinus cancer, the regulation of food intake, and oral cavity health; and (2) understand how prenatal and postnatal nutrition and environmental pollution affect the growth, development and health of the sense organs, as well as their expression of genes (including epigenetics) and proteins in humans and other animals.
Collapse
|
13
|
Huang HY, Chen P, Liang XF, Wu XF, Gu X, Xue M. Dietary N-Carbamylglutamate (NCG) alleviates liver metabolic disease and hepatocyte apoptosis by suppressing ERK1/2-mTOR-S6K1 signal pathway via promoting endogenous arginine synthesis in Japanese seabass (Lateolabrax japonicus). FISH & SHELLFISH IMMUNOLOGY 2019; 90:338-348. [PMID: 31075404 DOI: 10.1016/j.fsi.2019.04.294] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Revised: 04/23/2019] [Accepted: 04/26/2019] [Indexed: 06/09/2023]
Abstract
N-Carbamylglutamate (NCG), an analogue of N-acetylglutamate (NAG), can promote the synthesis of endogenous Arginine (Arg) in mammals, but not well studied in fish. This study was conducted to investigate the capacity of Arg endogenous synthesis by NCG, and the effects of various dietary NCG doses on growth performance, hepatic health and underlying nutrient regulation metabolism on ERK1/2-mTOR-S6K1 signaling pathway in Japanese seabass (Lateolabrax japonicus). Four experimental diets were prepared with NCG supplement levels of 0 (N0), 360 (N360), 720 (N720) and 3600 (N3600) mg/kg, in which N360 was at the maximum recommended level authorized by MOA, China in fish feed, and the N720 and N3600 levels were 2 and 10-fold of N360, respectively. Each diet was fed to 6 replicates with 30 Japanese seabass (initial body weight, IBW = 11.67 ± 0.02 g) in each tank. The results showed that the dietary NCG supplementation had no significant effects on the SGR and morphometric parameters of Japanese seabass, but 360-720 mg/kg NCG inclusion promoted PPV, while the 10-fold (3600 mg/kg) overdose of NCG had remarkably negative effects with significantly reduced feed efficiency, PPV and LPV. We found that Japanese seabass can utilize 360-720 mg/kg NCG to synthesis Arg to improve the amino acid metabolism by increasing plasma Arg and up-regulating intestinal ASL gene expression. Increased plasma GST and decreased MDA indicated the improved antioxidant response. Dietary NCG inclusion decreased plasma IgM and down-regulated the mRNA levels of inflammation (TNF-α and IL8), apoptosis (caspase family) and fibrosis (TGF-β1) related genes in the liver. The immunofluorescence examination revealed significantly decreased hepatic apoptosis and necrosis signals in the NCG groups. The ameliorated liver function and histological structure were closely related to the improved lipid metabolism parameters with decreased plasma VLDL and hepatic TG and NEFA accumulation, down-regulated fatty acid and cholesterol synthesis and simultaneously increased lipolysis gene mRNA levels, which regulated by inhibiting phosphorylation of ERK1/2-mTOR-S6K1 signaling pathway. Consuming 3600 mg/kg of dietary NCG is not safe for Japanese seabass culturing with the significantly increased FCR and decreased protein and lipid retention, and reduced plasma ALB. Accordingly, the observed efficacy and safety level of dietary NCG in the diet of Japanese seabass is 720 mg/kg.
Collapse
Affiliation(s)
- H Y Huang
- National Aquafeed Safety Assessment Center, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - P Chen
- National Aquafeed Safety Assessment Center, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - X F Liang
- National Aquafeed Safety Assessment Center, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - X F Wu
- National Aquafeed Safety Assessment Center, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - X Gu
- National Aquafeed Safety Assessment Center, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
| | - M Xue
- National Aquafeed Safety Assessment Center, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China; Key Laboratory of Feed Biotechnology of Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China; National Engineering Research Center of Biological Feed, 100081, China.
| |
Collapse
|
14
|
Yam M, Engel AL, Wang Y, Zhu S, Hauer A, Zhang R, Lohner D, Huang J, Dinterman M, Zhao C, Chao JR, Du J. Proline mediates metabolic communication between retinal pigment epithelial cells and the retina. J Biol Chem 2019; 294:10278-10289. [PMID: 31110046 PMCID: PMC6664195 DOI: 10.1074/jbc.ra119.007983] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Revised: 05/16/2019] [Indexed: 01/16/2023] Open
Abstract
The retinal pigment epithelium (RPE) is a monolayer of pigmented cells between the choroid and the retina. RPE dysfunction underlies many retinal degenerative diseases, including age-related macular degeneration, the leading cause of age-related blindness. To perform its various functions in nutrient transport, phagocytosis of the outer segment, and cytokine secretion, the RPE relies on an active energy metabolism. We previously reported that human RPE cells prefer proline as a nutrient and transport proline-derived metabolites to the apical, or retinal, side. In this study, we investigated how RPE utilizes proline in vivo and why proline is a preferred substrate. By using [13C]proline labeling both ex vivo and in vivo, we found that the retina rarely uses proline directly, whereas the RPE utilizes it at a high rate, exporting proline-derived mitochondrial intermediates for use by the retina. We observed that in primary human RPE cell culture, proline is the only amino acid whose uptake increases with cellular maturity. In human RPE, proline was sufficient to stimulate de novo serine synthesis, increase reductive carboxylation, and protect against oxidative damage. Blocking proline catabolism in RPE impaired glucose metabolism and GSH production. Notably, in an acute model of RPE-induced retinal degeneration, dietary proline improved visual function. In conclusion, proline is an important nutrient that supports RPE metabolism and the metabolic demand of the retina.
Collapse
Affiliation(s)
- Michelle Yam
- From the Departments of Ophthalmology and
- Biochemistry, West Virginia University, Morgantown, West Virginia 26506
| | - Abbi L Engel
- the Department of Ophthalmology, University of Washington, Seattle, Washington 98109
| | - Yekai Wang
- From the Departments of Ophthalmology and
- Biochemistry, West Virginia University, Morgantown, West Virginia 26506
| | - Siyan Zhu
- From the Departments of Ophthalmology and
- Biochemistry, West Virginia University, Morgantown, West Virginia 26506
| | - Allison Hauer
- From the Departments of Ophthalmology and
- Biochemistry, West Virginia University, Morgantown, West Virginia 26506
| | - Rui Zhang
- From the Departments of Ophthalmology and
- the Save Sight Institute, University of Sydney, 8 Macquarie Street, Sydney, New South Wales 2000, Australia
| | - Daniel Lohner
- From the Departments of Ophthalmology and
- Biochemistry, West Virginia University, Morgantown, West Virginia 26506
| | - Jiancheng Huang
- From the Departments of Ophthalmology and
- the Eye Institute, Eye and ENT Hospital, Shanghai Medical College, Fudan University, Shanghai 200031, China, and
- the Department of Ophthalmology, State Key Laboratory of Reproductive Medicine, First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China
| | - Marlee Dinterman
- From the Departments of Ophthalmology and
- Biochemistry, West Virginia University, Morgantown, West Virginia 26506
| | - Chen Zhao
- the Eye Institute, Eye and ENT Hospital, Shanghai Medical College, Fudan University, Shanghai 200031, China, and
| | - Jennifer R Chao
- the Department of Ophthalmology, University of Washington, Seattle, Washington 98109,
| | - Jianhai Du
- From the Departments of Ophthalmology and
- Biochemistry, West Virginia University, Morgantown, West Virginia 26506
| |
Collapse
|
15
|
Ginguay A, Cynober L, Curis E, Nicolis I. Ornithine Aminotransferase, an Important Glutamate-Metabolizing Enzyme at the Crossroads of Multiple Metabolic Pathways. BIOLOGY 2017; 6:biology6010018. [PMID: 28272331 PMCID: PMC5372011 DOI: 10.3390/biology6010018] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Revised: 02/23/2017] [Accepted: 02/24/2017] [Indexed: 02/06/2023]
Abstract
Ornithine δ-aminotransferase (OAT, E.C. 2.6.1.13) catalyzes the transfer of the δ-amino group from ornithine (Orn) to α-ketoglutarate (aKG), yielding glutamate-5-semialdehyde and glutamate (Glu), and vice versa. In mammals, OAT is a mitochondrial enzyme, mainly located in the liver, intestine, brain, and kidney. In general, OAT serves to form glutamate from ornithine, with the notable exception of the intestine, where citrulline (Cit) or arginine (Arg) are end products. Its main function is to control the production of signaling molecules and mediators, such as Glu itself, Cit, GABA, and aliphatic polyamines. It is also involved in proline (Pro) synthesis. Deficiency in OAT causes gyrate atrophy, a rare but serious inherited disease, a further measure of the importance of this enzyme.
Collapse
Affiliation(s)
- Antonin Ginguay
- Clinical Chemistry, Cochin Hospital, GH HUPC, AP-HP, 75014 Paris, France.
- Laboratory of Biological Nutrition, EA 4466 PRETRAM, Faculté de Pharmacie, Université Paris Descartes, 75006 Paris, France.
| | - Luc Cynober
- Clinical Chemistry, Cochin Hospital, GH HUPC, AP-HP, 75014 Paris, France.
- Laboratory of Biological Nutrition, EA 4466 PRETRAM, Faculté de Pharmacie, Université Paris Descartes, 75006 Paris, France.
| | - Emmanuel Curis
- Laboratoire de biomathématiques, plateau iB², Faculté de Pharmacie, Université Paris Descartes, 75006 Paris, France.
- UMR 1144, INSERM, Université Paris Descartes, 75006 Paris, France.
- UMR 1144, Université Paris Descartes, 75006 Paris, France.
- Service de biostatistiques et d'informatique médicales, hôpital Saint-Louis, Assistance publique-hôpitaux de Paris, 75010 Paris, France.
| | - Ioannis Nicolis
- Laboratoire de biomathématiques, plateau iB², Faculté de Pharmacie, Université Paris Descartes, 75006 Paris, France.
- EA 4064 "Épidémiologie environnementale: Impact sanitaire des pollutions", Faculté de Pharmacie, Université Paris Descartes, 75006 Paris, France.
| |
Collapse
|
16
|
Ornithine Aminotransferase Deficiency in Differential Diagnosis of Neonatal Hyperammonemia: A Case with a Novel OAT Gene Mutation. Indian J Pediatr 2016; 83:754-5. [PMID: 27037922 DOI: 10.1007/s12098-016-2077-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2015] [Accepted: 02/24/2016] [Indexed: 10/22/2022]
|
17
|
Palanza KM, Nesta AV, Tumu R, Walton CM, Davis MA, King TR. Auxotrophy-Based Detection of Hyperornithinemia in Mouse Blood and Urine. JOURNAL OF INBORN ERRORS OF METABOLISM AND SCREENING 2016. [DOI: 10.1177/2326409816649600] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Affiliation(s)
- Kenneth M. Palanza
- Biomolecular Sciences, Central Connecticut State University, New Britain, CT, USA
| | - Alex V. Nesta
- Biomolecular Sciences, Central Connecticut State University, New Britain, CT, USA
| | - Renukanandan Tumu
- Biomolecular Sciences, Central Connecticut State University, New Britain, CT, USA
| | - Cherie M. Walton
- Biomolecular Sciences, Central Connecticut State University, New Britain, CT, USA
| | - Michael A. Davis
- Biomolecular Sciences, Central Connecticut State University, New Britain, CT, USA
| | - Thomas R. King
- Biomolecular Sciences, Central Connecticut State University, New Britain, CT, USA
| |
Collapse
|
18
|
Haschke-Becher E, Kainz A, Bachmann C. Reference values of amino acids and of common clinical chemistry in plasma of healthy infants aged 1 and 4 months. J Inherit Metab Dis 2016; 39:25-37. [PMID: 26227325 DOI: 10.1007/s10545-015-9870-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Revised: 05/07/2015] [Accepted: 05/26/2015] [Indexed: 12/30/2022]
Abstract
OBJECTIVE To compare plasma levels of amino acids and clinical chemistry parameters in healthy infants at 1 and 4 months of age and to establish corresponding reference limits. METHODS Data of three multicenter studies assessing the safety of new infant formulas were used. During these studies infants of both age-groups were either breast-fed or received formulas of low or high protein content. All samples were analyzed centrally in the same accredited laboratory. RESULTS Plasma was collected from 521 infants in total, 157 boys and 135 girls aged 1 month and 121 boys and 108 girls aged 4 months. At the age of 1 month, 62 infants had received exclusively breast milk, 198 exclusively formula, and 27 both; in the 4-months age group corresponding numbers were 49, 158 and 18, respectively; for 9 infants, diet was unknown. Concentrations of most amino acids and clinical chemistry parameters differed significantly between both ages. Regardless of age, most plasma amino acid levels were comparable or lower in breast-fed than in formula-fed infants whereas at 1 month of age most clinical chemistry parameters were higher. While in breast-fed infants the plasma urea concentration decreased over 4 months of age, it increased in formula-fed infants. There were significant differences between infants fed a low and high protein formula. At both ages, high protein formulas resulted in significantly higher threonine, 2-aminobutyrate, and urea concentrations. CONCLUSIONS For clinical use, age- and diet specific reference limits in infants are warranted.
Collapse
Affiliation(s)
| | - Alexander Kainz
- Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria
| | - Claude Bachmann
- Laboratoire Central de Chimie Clinique, Centre Hospitalier Universitaire Vaudois, University of Lausanne, Rittergasse 11, CH-4103, Bottmingen, Switzerland.
| |
Collapse
|
19
|
Peng Y, Cooper SK, Li Y, Mei JM, Qiu S, Borchert GL, Donald SP, Kung HF, Phang JM. Ornithine-δ-Aminotransferase Inhibits Neurogenesis During Xenopus Embryonic Development. Invest Ophthalmol Vis Sci 2015; 56:2486-97. [PMID: 25783604 DOI: 10.1167/iovs.15-16509] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE In humans, deficiency of ornithine-δ-aminotransferase (OAT) results in progressive degeneration of the neural retina (gyrate atrophy) with blindness in the fourth decade. In this study, we used the Xenopus embryonic developmental model to study functions of the OAT gene on embryonic development. METHODS We cloned and sequenced full-length OAT cDNA from Xenopus oocytes (X-OAT) and determined X-OAT expression in various developmental stages of Xenopus embryos and in a variety of adult tissues. The phenotype, gene expression of neural developmental markers, and enzymatic activity were detected by gain-of-function and loss-of-function manipulations. RESULTS We showed that X-OAT is essential for Xenopus embryonic development, and overexpression of X-OAT produces a ventralized phenotype characterized by a small head, lack of axial structure, and defective expression of neural developmental markers. Using X-OAT mutants based on mutations identified in humans, we found that substitution of both Arg 180 and Leu 402 abrogated both X-OAT enzymatic activity and ability to modulate the developmental phenotype. Neurogenesis is inhibited by X-OAT during Xenopus embryonic development. CONCLUSIONS Neurogenesis is inhibited by X-OAT during Xenopus embryonic development, but it is essential for Xenopus embryonic development. The Arg 180 and Leu 402 are crucial for these effects of the OAT molecule in development.
Collapse
Affiliation(s)
- Ying Peng
- Department of Neurology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Sandra K Cooper
- Basic Research Program, Leidos, Inc., National Cancer Institute at Frederick, National Institutes of Health, Frederick, Maryland, United States
| | - Yi Li
- Department of Neurology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Jay M Mei
- Metabolism and Cancer Susceptibility Section, Basic Research Laboratory, National Cancer Institute at Frederick, National Institutes of Health, Frederick, Maryland, United States
| | - Shuwei Qiu
- Department of Neurology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Gregory L Borchert
- Basic Research Program, Leidos, Inc., National Cancer Institute at Frederick, National Institutes of Health, Frederick, Maryland, United States
| | - Steven P Donald
- Metabolism and Cancer Susceptibility Section, Basic Research Laboratory, National Cancer Institute at Frederick, National Institutes of Health, Frederick, Maryland, United States
| | - Hsiang-Fu Kung
- State Key Laboratory of Oncology in Southern China, and Centre for Emerging Infectious Diseases, the Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - James M Phang
- Metabolism and Cancer Susceptibility Section, Basic Research Laboratory, National Cancer Institute at Frederick, National Institutes of Health, Frederick, Maryland, United States
| |
Collapse
|
20
|
Ma HI, Hueng DY, Shui HA, Han JM, Wang CH, Lai YH, Cheng SY, Xiao X, Chen MT, Yang YP. Intratumoral decorin gene delivery by AAV vector inhibits brain glioblastomas and prolongs survival of animals by inducing cell differentiation. Int J Mol Sci 2014; 15:4393-414. [PMID: 24625664 PMCID: PMC3975403 DOI: 10.3390/ijms15034393] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2013] [Revised: 02/08/2014] [Accepted: 02/19/2014] [Indexed: 12/24/2022] Open
Abstract
Glioblastoma multiforme (GBM) is the most malignant cancer in the central nervous system with poor clinical prognosis. In this study, we investigated the therapeutic effect of an anti-cancer protein, decorin, by delivering it into a xenograft U87MG glioma tumor in the brain of nude mice through an adeno-associated viral (AAV2) gene delivery system. Decorin expression from the AAV vector in vitro inhibited cultured U87MG cell growth by induction of cell differentiation. Intracranial injection of AAV-decorin vector to the glioma-bearing nude mice in vivo significantly suppressed brain tumor growth and prolonged survival when compared to control non-treated mice bearing the same U87MG tumors. Proteomics analysis on protein expression profiles in the U87MG glioma cells after AAV-mediated decorin gene transfer revealed up- and down-regulation of important proteins. Differentially expressed proteins between control and AAV-decorin-transduced cells were identified through MALDI-TOF MS and database mining. We found that a number of important proteins that are involved in apoptosis, transcription, chemotherapy resistance, mitosis, and fatty acid metabolism have been altered as a result of decorin overexpression. These findings offer valuable insight into the mechanisms of the anti-glioblastoma effects of decorin. In addition, AAV-mediated decorin gene delivery warrants further investigation as a potential therapeutic approach for brain tumors.
Collapse
Affiliation(s)
- Hsin-I Ma
- Department of Neurological Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei 11490, Taiwan.
| | - Dueng-Yuan Hueng
- Department of Neurological Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei 11490, Taiwan.
| | - Hao-Ai Shui
- Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei 11490, Taiwan.
| | - Jun-Ming Han
- Department of Neurological Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei 11490, Taiwan.
| | - Chi-Hsien Wang
- Department of Neurological Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei 11490, Taiwan.
| | - Ying-Hsiu Lai
- Department of Medical Research and Education, Taipei Veterans General Hospital, Taipei 11217, Taiwan.
| | - Shi-Yuan Cheng
- Department of Neurology, Northwestern Brain Tumor Institute. The Robert H. Lurie Comprehensive Cancer Center, Center of Genetic Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA.
| | - Xiao Xiao
- Division of Molecular Pharmaceutics, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
| | - Ming-Teh Chen
- School of Medicine, National Yang-Ming University, Taipei 11221, Taiwan.
| | - Yi-Ping Yang
- Department of Neurological Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei 11490, Taiwan.
| |
Collapse
|
21
|
Bisaillon JJ, Radden LA, Szabo ET, Hughes SR, Feliciano AM, Nesta AV, Petrovic B, Palanza KM, Lancinskas D, Szmurlo TA, Artus DC, Kapper MA, Mulrooney JP, King TR. The retarded hair growth ( rhg) mutation in mice is an allele of ornithine aminotransferase ( Oat). Mol Genet Metab Rep 2014; 1:378-390. [PMID: 25264521 PMCID: PMC4171744 DOI: 10.1016/j.ymgmr.2014.08.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Because of the similar phenotypes they generate and their proximate reported locations on Chromosome 7, we tested the recessive retarded hair growth (rhg) and frizzy (fr) mouse mutations for allelism, but found instead that these defects complement. To discover the molecular basis of rhg, we analyzed a large intraspecific backcross panel that segregated for rhg and restricted this locus to a 0.9 Mb region that includes fewer than ten genes, only five of which have been reported to be expressed in skin. Complementation testing between rhg and a recessive null allele of fibroblast growth factor receptor 2 eliminated Fgfr2 as the possible basis of the retarded hair growth phenotype, but DNA sequencing of another of these candidates, ornithine aminotransferase (Oat), revealed a G to C transversion specifically associated with the rhg allele that would result in a glycine to alanine substitution at residue 353 of the gene product. To test whether this missense mutation might cause the mutant phenotype, we crossed rhg/rhg mice with mice that carried a recessive, perinatal-lethal, null mutation in Oat (designated OatΔ herein). Hybrid offspring that inherited both rhg and OatΔ displayed markedly delayed postnatal growth and hair development, indicating that these two mutations are allelic, and suggesting strongly that the G to C mutation in Oat is responsible for the retarded hair growth phenotype. Comparisons among +/+, +/rhg, rhg/rhg and rhg/OatΔ mice showed plasma ornithine levels and ornithine aminotransferase activities (in liver lysates) consistent with this assignment. Because histology of 7- and 12-month-old rhg/rhg and rhg/OatΔ retinas revealed chorioretinal degeneration similar to that described previously for OatΔ/OatΔ mice, we suggest that the rhg mutant may offer an ideal model for gyrate atrophy of the choroid and retina (GACR) in humans, which is also caused by the substitution of glycine 353 in some families. Genetic mapping identifies a small number of candidates for the mouse rhg mutation. Complementation testing between a null allele of Fgfr2 and rhg rules out allelism. A null allele of ornithine aminotransferase (Oat) fails to complement rhg. The rhg mutation results from a missense mutation in Oat. Mutant rhg/rhg mice show diminished OAT function, and chorioretinal degeneration.
Collapse
Affiliation(s)
- Jason J Bisaillon
- Biomolecular Sciences, Central Connecticut State University, 1615 Stanley Street, New Britain, CT 06053, USA
| | - Legairre A Radden
- Biomolecular Sciences, Central Connecticut State University, 1615 Stanley Street, New Britain, CT 06053, USA
| | - Eric T Szabo
- Biomolecular Sciences, Central Connecticut State University, 1615 Stanley Street, New Britain, CT 06053, USA
| | - Samantha R Hughes
- Biomolecular Sciences, Central Connecticut State University, 1615 Stanley Street, New Britain, CT 06053, USA
| | - Aaron M Feliciano
- Biomolecular Sciences, Central Connecticut State University, 1615 Stanley Street, New Britain, CT 06053, USA
| | - Alex V Nesta
- Biomolecular Sciences, Central Connecticut State University, 1615 Stanley Street, New Britain, CT 06053, USA
| | - Belinda Petrovic
- Biomolecular Sciences, Central Connecticut State University, 1615 Stanley Street, New Britain, CT 06053, USA
| | - Kenneth M Palanza
- Biomolecular Sciences, Central Connecticut State University, 1615 Stanley Street, New Britain, CT 06053, USA
| | - Dainius Lancinskas
- Biomolecular Sciences, Central Connecticut State University, 1615 Stanley Street, New Britain, CT 06053, USA
| | - Theodore A Szmurlo
- Biomolecular Sciences, Central Connecticut State University, 1615 Stanley Street, New Britain, CT 06053, USA
| | - David C Artus
- Biomolecular Sciences, Central Connecticut State University, 1615 Stanley Street, New Britain, CT 06053, USA
| | - Martin A Kapper
- Biomolecular Sciences, Central Connecticut State University, 1615 Stanley Street, New Britain, CT 06053, USA
| | - James P Mulrooney
- Biomolecular Sciences, Central Connecticut State University, 1615 Stanley Street, New Britain, CT 06053, USA
| | - Thomas R King
- Biomolecular Sciences, Central Connecticut State University, 1615 Stanley Street, New Britain, CT 06053, USA
| |
Collapse
|
22
|
Ladeuix B, Duchamp C, Levillain O. Underestimated contribution of skeletal muscle in ornithine metabolism during mouse postnatal development. Amino Acids 2013; 46:167-76. [DOI: 10.1007/s00726-013-1608-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Accepted: 10/19/2013] [Indexed: 02/08/2023]
|
23
|
Kasten J, Hu C, Bhargava R, Park H, Tai D, Byrne JA, Marescau B, De Deyn PP, Schlichting L, Grody WW, Cederbaum SD, Lipshutz GS. Lethal phenotype in conditional late-onset arginase 1 deficiency in the mouse. Mol Genet Metab 2013; 110:222-30. [PMID: 23920045 PMCID: PMC3800271 DOI: 10.1016/j.ymgme.2013.06.020] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2013] [Revised: 06/25/2013] [Accepted: 06/25/2013] [Indexed: 02/03/2023]
Abstract
Human arginase deficiency is characterized by hyperargininemia and infrequent episodes of hyperammonemia, which lead to neurological impairment with spasticity, loss of ambulation, seizures, and severe mental and growth retardation; uncommonly, patients suffer early death from this disorder. In a murine targeted knockout model, onset of the phenotypic abnormality is heralded by weight loss at around day 15, and death occurs typically by postnatal day 17 with hyperargininemia and markedly elevated ammonia. This discrepancy between the more attenuated juvenile-onset human disease and the lethal neonatal murine model has remained suboptimal for studying and developing therapy for the more common presentation of arginase deficiency. These investigations aimed to address this issue by creating an adult conditional knockout mouse to determine whether later onset of arginase deficiency also resulted in lethality. Animal survival and ammonia levels, body weight, circulating amino acids, and tissue arginase levels were examined as outcome parameters after widespread Cre-recombinase activation in a conditional knockout model of arginase 1 deficiency. One hundred percent of adult female and 70% of adult male mice died an average of 21.0 and 21.6 days, respectively, after the initiation of tamoxifen administration. Animals demonstrated elevated circulating ammonia and arginine at the onset of phenotypic abnormalities. In addition, brain and liver amino acids demonstrated abnormalities. These studies demonstrate that (a) the absence of arginase in adult animals results in a disease profile (leading to death) similar to that of the targeted knockout and (b) the phenotypic abnormalities seen in the juvenile-onset model are not exclusive to the age of the animal but instead to the biochemistry of the disorder. This adult model will be useful for developing gene- and cell-based therapies for this disorder that will not be limited by the small animal size of neonatal therapy and for developing a better understanding of the characteristics of hyperargininemia.
Collapse
Affiliation(s)
- Jennifer Kasten
- Department of Surgery, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Chuhong Hu
- Department of Surgery, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Ragini Bhargava
- Department of Surgery, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Hana Park
- Department of Surgery, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Denise Tai
- Department of Surgery, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - James A. Byrne
- Department of Molecular and Medical Pharmacology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Bart Marescau
- Laboratory of Neurochemistry and Behavior, University of Antwerp and Institute Born Bunge, Antwerp, Belgium
| | - Peter P. De Deyn
- Laboratory of Neurochemistry and Behavior, University of Antwerp and Institute Born Bunge, Antwerp, Belgium
| | - Lisa Schlichting
- Biochemical Genetics Laboratory, University of Colorado, Denver, CO, USA
| | - Wayne W. Grody
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
- Department of Pediatrics, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
- Department of Human Genetics, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Stephen D. Cederbaum
- Department of Pediatrics, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
- Department of Human Genetics, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
- Department of Psychiatry, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
- Intellectual and Developmental Disabilities Research Center at UCLA, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Gerald S. Lipshutz
- Department of Surgery, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
- Intellectual and Developmental Disabilities Research Center at UCLA, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
- Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
- Semel Institute for Neuroscience, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| |
Collapse
|
24
|
Marion V, Sankaranarayanan S, de Theije C, van Dijk P, Hakvoort TBM, Lamers WH, Köhler ES. Hepatic adaptation compensates inactivation of intestinal arginine biosynthesis in suckling mice. PLoS One 2013; 8:e67021. [PMID: 23785515 PMCID: PMC3681768 DOI: 10.1371/journal.pone.0067021] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2013] [Accepted: 05/13/2013] [Indexed: 11/18/2022] Open
Abstract
Suckling mammals, including mice, differ from adults in the abundant expression of enzymes that synthesize arginine from citrulline in their enterocytes. To investigate the importance of the small-intestinal arginine synthesis for whole-body arginine production in suckling mice, we floxed exon 13 of the argininosuccinate synthetase (Ass) gene, which codes for a key enzyme in arginine biosynthesis, and specifically and completely ablated Ass in enterocytes by crossing Ass (fl) and Villin-Cre mice. Unexpectedly, Ass (fl/fl) /VilCre (tg/-) mice showed no developmental impairments. Amino-acid fluxes across the intestine, liver, and kidneys were calculated after determining the blood flow in the portal vein, and hepatic and renal arteries (86%, 14%, and 33%, respectively, of the transhepatic blood flow in 14-day-old mice). Relative to control mice, citrulline production in the splanchnic region of Ass (fl/fl) /VilCre (tg/-) mice doubled, while arginine production was abolished. Furthermore, the net production of arginine and most other amino acids in the liver of suckling control mice declined to naught or even changed to consumption in Ass (fl/fl) /VilCre (tg/-) mice, and had, thus, become remarkably similar to that of post-weaning wild-type mice, which no longer express arginine-biosynthesizing enzymes in their small intestine. The adaptive changes in liver function were accompanied by an increased expression of genes involved in arginine metabolism (Asl, Got1, Gpt2, Glud1, Arg1, and Arg2) and transport (Slc25a13, Slc25a15, and Slc3a2), whereas no such changes were found in the intestine. Our findings suggest that the genetic premature deletion of arginine synthesis in enterocytes causes a premature induction of the post-weaning pattern of amino-acid metabolism in the liver.
Collapse
Affiliation(s)
- Vincent Marion
- Department of Anatomy & Embryology, Maastricht University, Maastricht, The Netherlands
- Laboratoire de Génetique Médicale, Institut National de la Santé et de la Recherche Médicale (INSERM) U1112, Strasbourg Cedex, France
| | | | - Chiel de Theije
- Department of Anatomy & Embryology, Maastricht University, Maastricht, The Netherlands
| | - Paul van Dijk
- Department of Anatomy & Embryology, Maastricht University, Maastricht, The Netherlands
| | - Theo B. M. Hakvoort
- Department of Anatomy & Embryology, Maastricht University, Maastricht, The Netherlands
- Tytgat Institute for Liver and Gastrointestinal Research, Academic Medical Center University of Amsterdam, Amsterdam, The Netherlands
| | - Wouter H. Lamers
- Department of Anatomy & Embryology, Maastricht University, Maastricht, The Netherlands
- Tytgat Institute for Liver and Gastrointestinal Research, Academic Medical Center University of Amsterdam, Amsterdam, The Netherlands
| | - Eleonore S. Köhler
- Department of Anatomy & Embryology, Maastricht University, Maastricht, The Netherlands
- *E-mail:
| |
Collapse
|
25
|
AAV-based gene therapy prevents neuropathology and results in normal cognitive development in the hyperargininemic mouse. Gene Ther 2013; 20:785-96. [PMID: 23388701 PMCID: PMC3679314 DOI: 10.1038/gt.2012.99] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2012] [Revised: 10/12/2012] [Accepted: 12/07/2012] [Indexed: 11/08/2022]
Abstract
Complete arginase I deficiency is the least severe urea cycle disorder, characterized by hyperargininemia and infrequent episodes of hyperammonemia. Patients suffer from neurological impairment with cortical and pyramidal tract deterioration, spasticity, loss of ambulation, and seizures, and is associated with intellectual disability. In mice, onset is heralded by weight loss beginning around day 15; gait instability follows progressing to inability to stand and development of tail tremor with seizure-like activity and death. Here we report that hyperargininemic mice treated neonatally with an adeno-associated virus expressing arginase and followed long-term lack any presentation consistent with brain dysfunction. Behavioral and histopathological evaluation demonstrated that treated mice are indistinguishable from littermates and that putative compounds associated with neurotoxicity are diminished. In addition, treatment results in near complete resolution of metabolic abnormalities early in life; however there is the development of some derangement later with decline in transgene expression. Ammonium challenging revealed that treated mice are affected by exogenous loading much greater than littermates. These results demonstrate that AAV-based therapy for hyperargininemia is effective and prevents development of neurological abnormalities and cognitive dysfunction in a mouse model of hyperargininemia; however nitrogen challenging reveals that these mice remain impaired in the handling of waste nitrogen.
Collapse
|
26
|
Marini JC, Stoll B, Didelija IC, Burrin DG. De novo synthesis is the main source of ornithine for citrulline production in neonatal pigs. Am J Physiol Endocrinol Metab 2012; 303:E1348-53. [PMID: 23074237 PMCID: PMC3774079 DOI: 10.1152/ajpendo.00399.2012] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Citrulline is an amino acid synthesized in the gut and utilized for the synthesis of the conditionally essential amino acid arginine. Recently, the origin of the ornithine utilized for citrulline synthesis has become a matter of discussion. Multiple physiological factors may have contributed to the differences found among different researchers; one of these is the developmental stage of the subjects studied. To test the hypothesis that during the neonatal period de novo synthesis is the main source of ornithine for citrulline synthesis, neonatal piglets were infused intravenously or intragastrically with [U-(13)C(6)]arginine, [U-(13)C(5)]glutamine, or [U-(13)C(5)]proline during the fasted and fed periods. [ureido-(15)N]citrulline and [(2)H(2)]ornithine were infused intravenously for the entire infusion protocol. During fasting, plasma proline (13%) and ornithine (19%) were the main precursors for citrulline synthesis, whereas plasma arginine (62%) was the main precursor for plasma ornithine. During feeding, enteral (27%) and plasma (12%) proline were the main precursors for the ornithine utilized in the synthesis of citrulline, together with plasma ornithine (27%). Enteral proline and glutamine were utilized directly by the gut to produce ornithine utilized for citrulline synthesis. Arginine was not utilized by the gut, which is consistent with the lack of arginase activity in the neonate. Arginine, however, was the main source (47%) of plasma ornithine and in this way contributed to citrulline synthesis. In conclusion, during the neonatal period, the de novo pathway is the predominant source for the ornithine utilized in the synthesis of citrulline, and proline is the preferred precursor.
Collapse
Affiliation(s)
- Juan C Marini
- United States Department of Agriculture/Agricultural Research Service Children’s Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA.
| | | | | | | |
Collapse
|
27
|
Doimo M, Desbats MA, Baldoin MC, Lenzini E, Basso G, Murphy E, Graziano C, Seri M, Burlina A, Sartori G, Trevisson E, Salviati L. Functional analysis of missense mutations of OAT, causing gyrate atrophy of choroid and retina. Hum Mutat 2012; 34:229-36. [PMID: 23076989 DOI: 10.1002/humu.22233] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2012] [Accepted: 09/04/2012] [Indexed: 11/07/2022]
Abstract
We studied eight kindreds with gyrate atrophy of choroid and retina (GA), a rare autosomal recessive disorder caused by mutations of the OAT gene, encoding the homoexameric enzyme ornithine-delta-aminotransferase. We identified four novel and five previously reported mutations. Missense alleles were expressed in yeast strain carrying a deletion of the orthologous of human OAT. All mutations markedly reduced enzymatic activity. However, the effect on the yeast growth was variable, suggesting that some mutations retain residual activity, below the threshold of the enzymatic assay. Mutant proteins were either highly unstable and rapidly degraded, or failed to assemble to form the active OAT hexamer. Where possible, fibroblast analysis confirmed these data. We found no correlation between the residual enzymatic activity and the age of onset, or the severity of symptoms. Moreover, the response to B6 was apparently not related to the specific mutations carried by patients. Overall these data suggest that other factors besides the specific OAT genotype modulate (GA) phenotype in patients. Finally, we found that 5-aminoimidazole-4-carboxamide ribonucleoside (AICAR), an AMPK activator known to increase mitochondrial biogenesis, markedly stimulates OAT expression, thus representing a possible treatment for a subset of GA patients with hypomorphic alleles.
Collapse
Affiliation(s)
- Mara Doimo
- Clinical Genetics Unit, Department of Woman and Child Health, University of Padova, Padova, Italy
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
28
|
Cho KI, Searle K, Webb M, Yi H, Ferreira PA. Ranbp2 haploinsufficiency mediates distinct cellular and biochemical phenotypes in brain and retinal dopaminergic and glia cells elicited by the Parkinsonian neurotoxin, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Cell Mol Life Sci 2012; 69:3511-27. [PMID: 22821000 PMCID: PMC3445802 DOI: 10.1007/s00018-012-1071-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2012] [Revised: 06/04/2012] [Accepted: 06/21/2012] [Indexed: 11/25/2022]
Abstract
Many components and pathways transducing multifaceted and deleterious effects of stress stimuli remain ill-defined. The Ran-binding protein 2 (RanBP2) interactome modulates the expression of a range of clinical and cell-context-dependent manifestations upon a variety of stressors. We examined the role of Ranbp2 haploinsufficiency on cellular and metabolic manifestations linked to tyrosine-hydroxylase (TH+) dopaminergic neurons and glial cells of the brain and retina upon acute challenge to 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), a parkinsonian neurotoxin, which models facets of Parkinson disease. MPTP led to stronger akinetic parkinsonism and slower recovery in Ranbp2+/− than wild-type mice without viability changes of brain TH+-neurons of either genotype, with the exception of transient nuclear atypia via changes in chromatin condensation of Ranbp2+/− TH+-neurons. Conversely, the number of wild-type retinal TH+-amacrine neurons compared to Ranbp2+/− underwent milder declines without apoptosis followed by stronger recoveries without neurogenesis. These phenotypes were accompanied by a stronger rise of EdU+-proliferative cells and non-proliferative gliosis of GFAP+-Müller cells in wild-type than Ranbp2+/− that outlasted the MPTP-insult. Finally, MPTP-treated wild-type and Ranbp2+/− mice present distinct metabolic footprints in the brain or selective regions thereof, such as striatum, that are supportive of RanBP2-mediated regulation of interdependent metabolic pathways of lysine, cholesterol, free-fatty acids, or their β-oxidation. These studies demonstrate contrasting gene-environment phenodeviances and roles of Ranbp2 between dopaminergic and glial cells of the brain and retina upon oxidative stress-elicited signaling and factors triggering a continuum of metabolic and cellular manifestations and proxies linked to oxidative stress, and chorioretinal and neurological disorders such as Parkinson.
Collapse
Affiliation(s)
- Kyoung-in Cho
- Department of Ophthalmology, Duke University Medical Center, DUEC 3802, 2351 Erwin Road, Durham, NC 27710 USA
| | - Kelly Searle
- Department of Ophthalmology, Duke University Medical Center, DUEC 3802, 2351 Erwin Road, Durham, NC 27710 USA
- Department of Epidemiology, The Johns Hopkins Bloomberg School of Public Health, 615 N. Wolfe Street, Baltimore, 21205 MD
| | - Mason Webb
- Department of Ophthalmology, Duke University Medical Center, DUEC 3802, 2351 Erwin Road, Durham, NC 27710 USA
| | - Haiqing Yi
- Department of Ophthalmology, Duke University Medical Center, DUEC 3802, 2351 Erwin Road, Durham, NC 27710 USA
| | - Paulo A. Ferreira
- Department of Ophthalmology, Duke University Medical Center, DUEC 3802, 2351 Erwin Road, Durham, NC 27710 USA
- Department of Pathology, Duke University Medical Center, Durham, NC 27710 USA
| |
Collapse
|
29
|
Senkevitch E, Cabrera-Luque J, Morizono H, Caldovic L, Tuchman M. A novel biochemically salvageable animal model of hyperammonemia devoid of N-acetylglutamate synthase. Mol Genet Metab 2012; 106:160-8. [PMID: 22503289 PMCID: PMC3356441 DOI: 10.1016/j.ymgme.2012.03.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2012] [Revised: 03/09/2012] [Accepted: 03/09/2012] [Indexed: 02/05/2023]
Abstract
All knockout mouse models of urea cycle disorders die in the neonatal period or shortly thereafter. Since N-acetylglutamate synthase (NAGS) deficiency in humans can be effectively treated with N-carbamyl-l-glutamate (NCG), we sought to develop a mouse model of this disorder that could be rescued by biochemical intervention, reared to adulthood, reproduce, and become a novel animal model for hyperammonemia. Founder NAGS knockout heterozygous mice were obtained from the trans-NIH Knock-Out Mouse Project. Genotyping of the mice was performed by PCR and confirmed by Western blotting of liver and intestine. NCG and L-citrulline (Cit) were used to rescue the NAGS knockout homozygous (Nags(-/-)) pups and the rescued animals were characterized. We observed an 85% survival rate of Nags(-/-) mice when they were given intraperitoneal injections with NCG and Cit during the newborn period until weaning and supplemented subsequently with both compounds in their drinking water. This regimen has allowed for normal development, apparent health, and reproduction. Interruption of this rescue intervention resulted in the development of severe hyperammonemia and death within 48 h. In addition to hyperammonemia, interruption of rescue supplementation was associated with elevated plasma glutamine, glutamate, and lysine, and reduced citrulline, arginine, ornithine and proline levels. We conclude that NAGS deprived mouse model has been developed which can be rescued by NCG and Cit and reared to reproduction and beyond. This biochemically salvageable mouse model recapitulates the clinical phenotype of proximal urea cycle disorders and can be used as a reliable model of induced hyperammonemia by manipulating the administration of the rescue compounds.
Collapse
Affiliation(s)
- Emilee Senkevitch
- Research Center for Genetic Medicine, Children’s National Medical Center, Washington DC, USA
- Biological Sciences Program, University of Maryland, College Park, Maryland, USA
| | - Juan Cabrera-Luque
- Research Center for Genetic Medicine, Children’s National Medical Center, Washington DC, USA
| | - Hiroki Morizono
- Research Center for Genetic Medicine, Children’s National Medical Center, Washington DC, USA
| | - Ljubica Caldovic
- Research Center for Genetic Medicine, Children’s National Medical Center, Washington DC, USA
| | - Mendel Tuchman
- Research Center for Genetic Medicine, Children’s National Medical Center, Washington DC, USA
| |
Collapse
|
30
|
Marini JC. Arginine and ornithine are the main precursors for citrulline synthesis in mice. J Nutr 2012; 142:572-80. [PMID: 22323761 PMCID: PMC3278269 DOI: 10.3945/jn.111.153825] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Recent isotopic tracer studies in mice, piglets, and humans have produced conflicting results as to the main carbon skeleton precursor for citrulline and arginine synthesis. This may be due in part to the different tracers infused and models used to interpret the stable isotope data. Furthermore, previous studies usually investigated a single precursor, which prevented the direct comparison among multiple precursors. To further elucidate the contribution of different precursors to citrulline synthesis, all possible enteral and plasma precursors of citrulline were studied in a mouse model during the postabsorptive and postprandial period using multitracer protocols. In addition, three different models were used to interpret the stable isotope data. The utilization of the classic precursor-product equation, developed for i.v. infused tracers but also used to include i.g. tracers, grossly overestimated the contribution of enteral precursors. Regardless of the model employed, dietary and plasma arginine were the main precursors for citrulline synthesis during feeding and plasma arginine during feed deprivation. The contribution of arginine was directly at the site of citrulline synthesis and through plasma ornithine. The predominant role of arginine and ornithine seen in this study supports the observations in mice, piglets, and humans suggesting that ornithine amino transferase is a pivotal enzyme in this pathway.
Collapse
|
31
|
Tanzer F, Firat M, Alagoz M, Erdogan H. Gyrate atrophy of the choroid and retina with hyperornithinemia, cystinuria and lysinuria responsive to vitamin B6. BMJ Case Rep 2011; 2011:2011/mar10_1/bcr0720103200. [PMID: 22698901 DOI: 10.1136/bcr.07.2010.3200] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
In this report, an 8-year-old girl is presented with the complaint of progressive night blindness. The authors have performed eye funduscopy, which showed chorioretinal atrophy in gyrate shape. A high level of plasma ornithine was determined. Urinary excretion of ornithine as well as lysine and cystine were increased. Patient was treated with high dose pyridoxine supplement (500 mg/dl). The night blindness condition of the patient improved. After 1 month of pyridoxine therapy ornithine level of her plasma was successfully reduced and blindness improved.
Collapse
Affiliation(s)
- Fatos Tanzer
- Department of Pediatric Metabolism, Cumhuriyet University Medical Faculty, Sivas, Turkey.
| | | | | | | |
Collapse
|
32
|
Abstract
Natural products have evolved to encompass a broad spectrum of chemical and functional diversity. It is this diversity, along with their structural complexity, that enables nature's small molecules to target a nearly limitless number of biological macromolecules and to often do so in a highly selective fashion. Because of these characteristics, natural products have seen great success as therapeutic agents. However, this vast pool of compounds holds much promise beyond the development of future drugs. These features also make them ideal tools for the study of biological systems. Recent examples of the use of natural products and their derivatives as chemical probes to explore biological phenomena and assemble biochemical pathways are presented here.
Collapse
Affiliation(s)
- Erin E. Carlson
- Departments of Chemistry and Molecular and Cellular Biochemistry, Indiana University, 212 S. Hawthorne Drive, Bloomington, Indiana 47405
| |
Collapse
|
33
|
Abstract
Although glutamine is considered the main precursor for citrulline synthesis, the current literature does not differentiate between the contribution of glutamine carbon skeleton vs. nonspecific nitrogen (i.e., ammonia) and carbon derived from glutamine oxidation. To elucidate the role of glutamine and nonspecific nitrogen in the synthesis of citrulline, l-[2-(15)N]- and l-[5-(15)N]glutamine and (15)N-ammonium acetate were infused intragastrically in mice. The amino group of glutamine labeled the three nitrogen groups of citrulline almost equally. The amido group and ammonium acetate labeled the ureido and amino groups of citrulline, but not the delta-nitrogen. D(5)-glutamine also infused in this arm of the study, which traces the carbon skeleton of glutamine, was utilized poorly, accounting for only 0.2-0.4% of the circulating citrulline. Dietary glutamine nitrogen (both N groups) incorporation was 25-fold higher than the incorporation of its carbon skeleton into citrulline. To investigate the relative contributions of the carbon skeleton and nonspecific carbon of glutamine, arginine, and proline to citrulline synthesis, U-(13)C(n) tracers of these amino acids were infused intragastrically. Dietary arginine was the main precursor for citrulline synthesis, accounting for approximately 40% of the circulating citrulline. Proline contribution was minor (3.4%), and glutamine was negligible (0.4%). However, the glutamine tracer resulted in a higher enrichment in the ureido group, indicating incorporation of nonspecific carbon from glutamine oxidation into carbamylphosphate used for citrulline synthesis. In conclusion, dietary glutamine is a poor carbon skeleton precursor for the synthesis of citrulline, although it contributes both nonspecific nitrogen and carbon to citrulline synthesis.
Collapse
Affiliation(s)
- Juan C Marini
- Children's Nutrition Research Center, Department of Pediatrics, United States Department of Agriculture/Agricultural Research Service, 1100 Bates Street, Houston, TX 77030, USA.
| | | | | | | |
Collapse
|
34
|
Ventura G, Moinard C, Segaud F, Le Plenier S, Cynober L, De Bandt JP. Adaptative response of nitrogen metabolism in early endotoxemia: role of ornithine aminotransferase. Amino Acids 2010; 39:1417-26. [DOI: 10.1007/s00726-010-0601-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2009] [Accepted: 04/16/2010] [Indexed: 10/19/2022]
|
35
|
Samardzija M, Neuhauss SCF, Joly S, Kurz-Levin M, Grimm C. Animal Models for Retinal Degeneration. NEUROMETHODS 2010. [DOI: 10.1007/978-1-60761-541-5_4] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|
36
|
Short-term correction of arginase deficiency in a neonatal murine model with a helper-dependent adenoviral vector. Mol Ther 2009; 17:1155-63. [PMID: 19367256 DOI: 10.1038/mt.2009.65] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Neonatal gene therapy has the potential to ameliorate abnormalities before disease onset. Our gene knockout of arginase I (AI) deficiency is characterized by increasing hyperammonemia, neurological deterioration, and early death. We constructed a helper-dependent adenoviral vector (HDV) carrying AI and examined for correction of this defect. Neonates were administered 5 x 10(9) viral particles/g and analyzed for survival, arginase activity, and ammonia and amino acids levels. The life expectancy of arg(-/-) mice increased to 27 days while controls died at 14 days with hyperammonemia and in extremis. Death correlated with a decrease in viral DNA/RNA per cell as liver mass increased. Arginase assays demonstrated that vector-injected hepatocytes had ~20% activity of heterozygotes at 2 weeks of age. Hepatic arginine and ornithine in treated mice were similar to those of saline-injected heterozygotes at 2 weeks, whereas ammonia was normal. By 26 days, arginase activity in the treated arg(-/-) livers declined to <10%, and arginine and ornithine increased. Ammonia levels began increasing by day 25, suggesting the cause of death to be similar to that of uninjected arg(-/-) mice, albeit at a later time. These studies demonstrate that the AI deficient newborn mouse can be temporarily corrected and rescued using a HDV.
Collapse
|
37
|
The human neonatal small intestine has the potential for arginine synthesis; developmental changes in the expression of arginine-synthesizing and -catabolizing enzymes. BMC DEVELOPMENTAL BIOLOGY 2008; 8:107. [PMID: 19000307 PMCID: PMC2621195 DOI: 10.1186/1471-213x-8-107] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/14/2008] [Accepted: 11/10/2008] [Indexed: 11/19/2022]
Abstract
Background Milk contains too little arginine for normal growth, but its precursors proline and glutamine are abundant; the small intestine of rodents and piglets produces arginine from proline during the suckling period; and parenterally fed premature human neonates frequently suffer from hypoargininemia. These findings raise the question whether the neonatal human small intestine also expresses the enzymes that enable the synthesis of arginine from proline and/or glutamine. Carbamoylphosphate synthetase (CPS), ornithine aminotransferase (OAT), argininosuccinate synthetase (ASS), arginase-1 (ARG1), arginase-2 (ARG2), and nitric-oxide synthase (NOS) were visualized by semiquantitative immunohistochemistry in 89 small-intestinal specimens. Results Between 23 weeks of gestation and 3 years after birth, CPS- and ASS-protein content in enterocytes was high and then declined to reach adult levels at 5 years. OAT levels declined more gradually, whereas ARG-1 was not expressed. ARG-2 expression increased neonatally to adult levels. Neurons in the enteric plexus strongly expressed ASS, OAT, NOS1 and ARG2, while varicose nerve fibers in the circular layer of the muscularis propria stained for ASS and NOS1 only. The endothelium of small arterioles expressed ASS and NOS3, while their smooth-muscle layer expressed OAT and ARG2. Conclusion The human small intestine acquires the potential to produce arginine well before fetuses become viable outside the uterus. The perinatal human intestine therefore resembles that of rodents and pigs. Enteral ASS behaves as a typical suckling enzyme because its expression all but disappears in the putative weaning period of human infants.
Collapse
|
38
|
Dekaney CM, Wu G, Yin YL, Jaeger LA. Regulation of ornithine aminotransferase gene expression and activity by all-transretinoic acid in Caco-2 intestinal epithelial cells. J Nutr Biochem 2008; 19:674-81. [DOI: 10.1016/j.jnutbio.2007.09.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2007] [Revised: 08/14/2007] [Accepted: 09/04/2007] [Indexed: 10/22/2022]
|
39
|
Mumenthaler SM, Rozengurt N, Livesay JC, Sabaghian A, Cederbaum SD, Grody WW. Disruption of arginase II alters prostate tumor formation in TRAMP mice. Prostate 2008; 68:1561-9. [PMID: 18663728 DOI: 10.1002/pros.20816] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND Arginase II (AII) is involved in the polyamine synthetic pathway, and elevated levels of expression have been found in a high proportion of prostate cancer samples and patients. However, the biological function of arginase II in prostate cancer still remains to be elucidated. In this study, we utilized the TRAMP mouse prostate cancer model to better understand the contribution of AII on tumor development. METHODS AII expression was determined in prostates from TRAMP mice at 23 weeks of age by real-time RT-PCR and Western blot analysis. Additionally, AII expression was disrupted in the TRAMP model by crossbreeding arginase II knockout (AII KO) mice with TRAMP mice in order to generate the TRAMP/AII KO line. In each group, genito-urinary (GU) tract weights were determined and a pathological evaluation of the tumors was completed. RESULTS AII expression was only detectable in those mice without the presence of macroscopic tumors; it was also absent in the TRAMP-C2 cell line, which is characteristic of an advanced prostate tumor. Assessment of the GU weights revealed larger average GU weights in the TRAMP/AII KO mice compared to TRAMP mice. Additionally, a greater percentage of more advanced pathology was found in the TRAMP/AII KO group compared to the TRAMP cohort. CONCLUSIONS Based on these results, AII deficiency in the TRAMP model seems to accelerate prostate tumor progression, leading to an overall more advanced cancer stage in these mice. These findings support the possibility that prostatic arginase II could be a potentially useful marker of disease progression.
Collapse
MESH Headings
- Adenocarcinoma/enzymology
- Adenocarcinoma/metabolism
- Adenocarcinoma/pathology
- Animals
- Arginase/biosynthesis
- Arginase/genetics
- Arginase/metabolism
- Blotting, Western
- Cell Line, Tumor
- Hyperargininemia
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Mice, Transgenic
- Neoplasms, Hormone-Dependent/enzymology
- Neoplasms, Hormone-Dependent/metabolism
- Prostatic Neoplasms/enzymology
- Prostatic Neoplasms/metabolism
- Prostatic Neoplasms/pathology
- RNA, Neoplasm/chemistry
- RNA, Neoplasm/genetics
- Receptors, Tumor Necrosis Factor, Member 25/genetics
- Receptors, Tumor Necrosis Factor, Member 25/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
Collapse
Affiliation(s)
- Shannon M Mumenthaler
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine at UCLA, Los Angeles, California 90095-1732, USA
| | | | | | | | | | | |
Collapse
|
40
|
Abstract
Ornithine aminotransferase (OAT) is a reversible enzyme expressed mainly in the liver, kidney and intestine. OAT controls the interconversion of ornithine into glutamate semi-aldehyde, and is therefore involved in the metabolism of arginine and glutamine which play a major role in N homeostasis. We hypothesised that OAT could be a limiting step in glutamine–arginine interconversion. To study the contribution of the OAT enzyme in amino acid metabolism, transgenic mice that specifically overexpress human OAT in the liver, kidneys and intestine were generated. The transgene expression was analysed byin situhybridisation and real-time PCR. Tissue (liver, jejunum and kidney) OAT activity, and plasma and tissue (liver and jejunum) amino acid concentrations were measured. Transgenic male mice exhibited higher OAT activity in the liver (25 (sem4)v.11 (sem1) nmol/min per μg protein for wild-type (WT) mice;P < 0·05) but there were no differences in kinetic parameters (i.e.Kmand maximum rate of reaction (Vmax)) between WT and transgenic animals. OAT overexpression decreased plasma and liver ornithine concentrations but did not affect glutamine or arginine homeostasis. There was an inverse relationship between ornithine levels and OAT activity. We conclude that OAT overexpression has only limited metabolic effects, probably due to the reversible nature of the enzyme. Moreover, these metabolic modifications had no effect on phenotype.
Collapse
|
41
|
Williams NS, Burgett AWG, Atkins AS, Wang X, Harran PG, McKnight SL. Therapeutic anticancer efficacy of a synthetic diazonamide analog in the absence of overt toxicity. Proc Natl Acad Sci U S A 2007; 104:2074-9. [PMID: 17287337 PMCID: PMC1794345 DOI: 10.1073/pnas.0611340104] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2006] [Indexed: 11/18/2022] Open
Abstract
Blocking cell division through the inhibition of mitosis is one of the most successful clinical strategies for the treatment of cancer. Taxanes and vinca alkaloids are in widespread use and have demonstrated substantive therapeutic efficacy. Both classes of compounds bind directly to tubulin, a structural component of the mitotic spindle. The ubiquitous utilization of tubulin in cell division in both cancerous and normal cells, however, tempers the broad spectrum of activity of currently used antimitotics by significant toxicities in normal dividing tissue. Moreover, peripheral nerve cells that rely on microtubules to shuttle cargo along axonal processes are also damaged by tubulin-binding drugs. Thus, neutropenia and peripheral neuropathy are the most frequently cited dose-limiting toxicities of this class of chemotherapeutics. Here we report the preclinical assessment of AB-5, a structural and functional analog of the natural product diazonamide A. AB-5, like taxanes and vinca alkaloids, blocks cell division during mitosis. However, AB-5 works not by binding tubulin but rather through inhibition of a newly discovered role for ornithine-delta-aminotransferase in mitosis. We hereby report that, unlike other antimitotics, AB-5 is extremely well tolerated by mice when administered under conditions where the drug cures xenografted tumors as effectively as taxanes and vinca alkaloids. AB-5-treated mice show no weight loss, no change in overall physical appearance, and no evidence of neutropenia. These observations raise the possibility that AB-5 may have clinical utility for cancer therapy under conditions largely devoid of chemotherapeutic toxicity and suggest that further preclinical evaluation of AB-5 is warranted.
Collapse
Affiliation(s)
| | | | | | - Xiaodong Wang
- *Department of Biochemistry and
- Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390
| | | | | |
Collapse
|
42
|
Wang G, Shang L, Burgett AWG, Harran PG, Wang X. Diazonamide toxins reveal an unexpected function for ornithine delta-amino transferase in mitotic cell division. Proc Natl Acad Sci U S A 2007; 104:2068-73. [PMID: 17287350 PMCID: PMC1894683 DOI: 10.1073/pnas.0610832104] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We have studied a naturally occurring small-molecule antimitotic called diazonamide A. Diazonamide A is highly effective at blocking spindle assembly in mammalian cell culture and does so through a unique mechanism. A biotinylated form of diazonamide A affinity purifies ornithine delta-amino transferase (OAT), a mitochondrial enzyme, from HeLa cell and Xenopus egg extracts. In the latter system, the interaction between diazonamide A and OAT is regulated by RanGTP. We find that specific OAT knockdown in human cervical carcinoma and osteosarcoma cells by RNA interference blocks cell division and causes cell death, the effects largely phenocopying diazonamide A treatment in these cell lines. Our experiments reveal an unanticipated, paradoxical role for OAT in mitotic cell division and identify the protein as a target for chemotherapeutic drug development.
Collapse
Affiliation(s)
- Gelin Wang
- *Department of Biochemistry, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390-9038
| | - Libin Shang
- *Department of Biochemistry, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390-9038
| | - Anthony W. G. Burgett
- *Department of Biochemistry, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390-9038
| | - Patrick G. Harran
- *Department of Biochemistry, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390-9038
- To whom correspondence may be addressed. E-mail:
or
| | - Xiaodong Wang
- Howard Hughes Medical Institute and
- *Department of Biochemistry, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390-9038
- To whom correspondence may be addressed. E-mail:
or
| |
Collapse
|
43
|
Loï C, Hamani D, Moinard C, Bishoff L, Neveux N, Garbay C, Cynober L. Does the ornithine-alpha-ketoglutarate ratio influence ornithine alpha-ketoglutarate metabolism in healthy rats? Metabolism 2007; 56:105-14. [PMID: 17161232 DOI: 10.1016/j.metabol.2006.09.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2005] [Accepted: 09/03/2006] [Indexed: 11/29/2022]
Abstract
Ornithine alpha-ketoglutarate (OKG) is a salt composed of 2 molecules of ornithine (ORN) and one molecule of alpha-ketoglutarate (alphaKG). OKG has been used successfully via oral, enteral, and parenteral routes to improve protein status in patients with chronic and acute protein depletion, but its mechanism of action, which is probably multifactorial, is still unclear. A specific metabolic interaction between alphaKG and ORN has been shown to be a key factor in the effects of OKG, but the impact of the ORN/alphaKG ratio (2 molecules of ORN for 1 molecule of alphaKG) has never been discussed. To clarify this point, young (3 weeks old) male Wistar rats in the postabsorptive state received 5 g/kg of either OKG or a mono-ornithine alphaKG (MOKG) salt (ORN/alphaKG ratio = 1:1) in amounts that were either isonitrogenous or isomolar to OKG, or a saline solution (controls) and were killed 1 hour later. In a second experiment, a kinetic study was performed in which rats were killed 1, 2, 3, or 6 hours after OKG, MOKG, or saline administration. Amino acid contents were analyzed in the plasma, liver, jejunal and ileal mucosae, and the extensor digitorum longus (EDL) muscle. The major metabolites detected after intake of OKG or MOKG (ie, ORN, proline [PRO], and glutamate; OKG and MOKG vs control, P < .05) together with the absence of increased arginine and citrulline levels suggested that ORN was mainly metabolized by the ORN aminotransferase pathway, leading to glutamate and PRO production with accumulation persisting at 6 hours postadministration. This study provides new and important data on the influence of the ORN/alphaKG ratio on OKG metabolism: MOKG-treated rats presented less intestinal ORN than OKG-treated rats (MOKG vs OKG, P < .05), suggesting that ORN/alphaKG ratio influences the rate of ORN availability and metabolism. In addition, the metabolic interaction between ORN and alphaKG (ie, in the presence of alphaKG, ORN metabolism is partially diverted toward PRO production), which is characteristic of OKG metabolism, still takes place even if the salt contains only 1 molecule of ORN instead of two.
Collapse
Affiliation(s)
- Cécile Loï
- Laboratoire de Biologie de la Nutrition, EA 2498, Faculté de Pharmacie, Université Paris Descartes, 75270 Paris Cedex 06, France.
| | | | | | | | | | | | | |
Collapse
|
44
|
Yang B, Zhao D, Solenov E, Verkman AS. Evidence from knockout mice against physiologically significant aquaporin 8-facilitated ammonia transport. Am J Physiol Cell Physiol 2006; 291:C417-23. [PMID: 16624991 DOI: 10.1152/ajpcell.00057.2006] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Aquaporin (AQP)8-facilitated transport of NH3has been suggested recently by increased NH3permeability in Xenopus oocytes and yeast expressing human or rat AQP8. We tested the proposed roles of AQP8-facilitated NH3transport in mammalian physiology by comparative phenotype studies in wild-type vs. AQP8-null mice. AQP8-facilitated NH3transport was confirmed in mammalian cell cultures expressing rat or mouse AQP8, in which the fluorescence of a pH-sensing yellow fluorescent protein was measured in response to ammonia (NH3/NH4+) gradients. Relative AQP8 single-channel NH3-to-water permeability was ∼0.03. AQP8-facilitated NH3and water permeability in a native tissue was confirmed in membrane vesicles isolated from testes of wild-type vs. AQP8-null mice, in which BCECF was used as an intravesicular pH indicator. A series of in vivo studies were done in mice, including 1) serum ammonia measurements before and after ammonia infusion, 2) renal ammonia clearance, 3) colonic ammonia absorption, and 4) liver ammonia accumulation and renal ammonia excretion after acute and chronic ammonia loading. Except for a small reduction in hepatic ammonia accumulation and increase in ammonia excretion in AQP8-null mice loaded with large amounts of ammonia, there were no significant differences in wild-type vs. AQP8-null mice. Our results support the conclusion that AQP8 can facilitate NH3transport but provide evidence against physiologically significant AQP8-facilitated NH3transport in mice.
Collapse
Affiliation(s)
- Baoxue Yang
- 1246 Health Sciences East Tower, Box 0521, University of California-San Francisco, San Francisco, CA 94143-0521, USA.
| | | | | | | |
Collapse
|
45
|
Wu G, Knabe D, Flynn N. Chapter 5 Amino acid metabolism in the small intestine: biochemical bases and nutritional significance. ACTA ACUST UNITED AC 2005. [DOI: 10.1016/s1877-1823(09)70012-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
|
46
|
Cleary MA, Dorland L, de Koning TJ, Poll-The BT, Duran M, Mandell R, Shih VE, Berger R, Olpin SE, Besley GTN. Ornithine aminotransferase deficiency: diagnostic difficulties in neonatal presentation. J Inherit Metab Dis 2005; 28:673-9. [PMID: 16151897 DOI: 10.1007/s10545-005-0074-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2004] [Accepted: 03/31/2005] [Indexed: 11/29/2022]
Abstract
We describe two unrelated cases of ornithine aminotransferase (OAT) deficiency with rare neonatal presentation of hyperammonaemia. The diagnosis in the neonatal presentation of OAT deficiency is hampered as hyperornithinaemia is absent. Enzyme and mutation studies confirmed the diagnosis. OAT deficiency should be included in differential diagnosis of neonatal hyperammonaemia.
Collapse
Affiliation(s)
- M A Cleary
- Willink Biochemical Genetics Unit, Royal Manchester Children's Hospital, Pendlebury, Manchester, UK
| | | | | | | | | | | | | | | | | | | |
Collapse
|
47
|
Xu S, Wang Y, Zhao H, Zhang L, Xiong W, Yau KW, Hiel H, Glowatzki E, Ryugo DK, Valle D. PHR1, a PH domain-containing protein expressed in primary sensory neurons. Mol Cell Biol 2004; 24:9137-51. [PMID: 15456885 PMCID: PMC517893 DOI: 10.1128/mcb.24.20.9137-9151.2004] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Previously, we identified PHR1 as an abundantly expressed gene in photoreceptors and showed that it encodes four isoforms, each with N-terminal pleckstrin homology (PH) and C-terminal transmembrane domains. To better understand PHR1 function and expression, we made a Phr1 null mouse by inserting a beta-galactosidase/neor cassette into exon 3. In addition to photoreceptors, we found abundant expression of specific Phr1 splice forms in olfactory receptor neurons and vestibular and cochlear hair cells. We also found Phr1 expression in cells with a possible sensory function, including peripheral retinal ganglion cells, cochlear interdental cells, and neurons of the circumventricular organ. Despite this discrete expression in known and putative sensory neurons, mice lacking PHR1 do not have overt sensory deficits.
Collapse
Affiliation(s)
- Shunbin Xu
- McKusick-Nathans Institute of Genetic Medicine, Howard Hughes Medical Institute, PCTB 519, 733 N. Broadway, Baltimore, MD 21205, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
48
|
Wu G, Jaeger LA, Bazer FW, Rhoads JM. Arginine deficiency in preterm infants: biochemical mechanisms and nutritional implications. J Nutr Biochem 2004; 15:442-51. [PMID: 15302078 DOI: 10.1016/j.jnutbio.2003.11.010] [Citation(s) in RCA: 160] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2003] [Revised: 10/29/2003] [Accepted: 11/07/2003] [Indexed: 12/01/2022]
Abstract
Arginine, an amino acid that is nutritionally essential for the fetus and neonate, is crucial for ammonia detoxification and the synthesis of molecules with enormous importance (including creatine, nitric oxide, and polyamines). A significant nutritional problem in preterm infants is a severe deficiency of arginine (hypoargininemia), which results in hyperammonemia, as well as cardiovascular, pulmonary, neurological, and intestinal dysfunction. Arginine deficiency may contribute to the high rate of infant morbidity and mortality associated with premature births. Although hypoargininemia in preterm infants has been recognized for more than 30 years, it continues to occur in neonatal intensive care units in the United States and worldwide. On the basis of recent findings, we propose that intestinal citrulline and arginine synthesis (the major endogenous source of arginine) is limited in preterm neonates owing to the limited expression of the genes for key enzymes (e.g., pyrroline-5-carboxylate synthase, argininosuccinate synthase and lyase), thereby contributing to hypoargininemia. Because premature births in humans occur before the normal perinatal surge of cortisol (an inducer of the expression of key arginine-synthetic enzymes), its administration may be a useful tool to advance the maturation of intestinal arginine synthesis in preterm neonates. Additional benefits of cortisol treatment may include the following: 1) allowing early introduction of enteral feeding to preterm infants, which is critical for intestinal synthesis of citrulline, arginine, and polyamines as well as for intestinal motility, integrity, and growth; and 2) shortening the expensive stay of preterm infants in hospitals as a result of accelerated organ maturation and the restoration of full enteral feeding. Further studies of fetal and neonatal arginine metabolism will continue to advance our understanding of the mechanisms responsible for the survival and growth of preterm infants. This new knowledge will be beneficial for designing the next generation of enteral and parenteral amino acid solutions to optimize nutrition and health in this compromised population.
Collapse
Affiliation(s)
- Guoyao Wu
- Faculty of Nutrition, Texas A&M University, College Station, TX 77843, USA.
| | | | | | | |
Collapse
|
49
|
Abstract
The concentration of arginine (an essential amino acid for neonates) in sow's milk is remarkably low, and thus endogenous synthesis of arginine plays a crucial role in maintaining arginine homeostasis in milk-fed piglets. Paradoxically, intestinal synthesis of citrulline from glutamine/glutamate and proline (the endogenous source of arginine) declines markedly in 7- to 21-d-old suckling pigs, compared with 1- to 3-d-old pigs. Therefore, plasma concentrations of arginine and its immediate precursors (ornithine and citrulline) decrease progressively by 20-41%, whereas plasma ammonia levels increase progressively by 18-46%, between d 3 and 14 of life. Dietary supplementation of 0.2 and 0.4% arginine to 7- to 21-d-old pigs (artificially reared on a milk feeding system) dose dependently enhances the plasma arginine concentration (30 and 61%), reduces the plasma ammonia level (20 and 35%), and increases weight gain (28 and 66%). These compelling metabolic and growth data demonstrate unequivocally that arginine is insufficient for supporting the maximal growth in milk-fed young pigs and that this arginine deficiency represents a major obstacle to realizing the growth potential in piglets. A low concentration of mitochondrial N-acetylglutamate (an activator of both pyrroline-5-carboxylate synthase and carbamoylphosphate synthase-I) is responsible for the striking decline in the intestinal synthesis of citrulline and arginine during the suckling period. Accordingly, oral administration of N-carbamoylglutamate [a metabolically stable analogue of N-acetylglutamate; 2 x 50 mg/(kg body wt . d)] enhances plasma arginine level (68%) and weight gain (61%) of 4- to 14-d-old sow-reared pigs. Thus, the metabolic activation of intestinal citrulline and arginine synthesis provides a novel, effective means to increase endogenous arginine provision and therefore piglet growth (a major goal of animal agriculture). Our findings not only generate new fundamental knowledge about amino acid utilization by neonatal pigs, but they also have important practical implications for improving the efficiency of pork production.
Collapse
Affiliation(s)
- Guoyao Wu
- Department of Animal Science and Faculty of Nutrition, Texas A&M University, College Station, TX 77843-2471, USA.
| | | | | |
Collapse
|
50
|
Yu H, Yoo PK, Aguirre CC, Tsoa RW, Kern RM, Grody WW, Cederbaum SD, Iyer RK. Widespread expression of arginase I in mouse tissues. Biochemical and physiological implications. J Histochem Cytochem 2003; 51:1151-60. [PMID: 12923240 DOI: 10.1177/002215540305100905] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Arginase I (AI), the fifth and final enzyme of the urea cycle, detoxifies ammonia as part of the urea cycle. In previous studies from others, AI was not found in extrahepatic tissues except in primate blood cells, and its roles outside the urea cycle have not been well recognized. In this study we undertook an extensive analysis of arginase expression in postnatal mouse tissues by in situ hybridization (ISH) and RT-PCR. We also compared arginase expression patterns with those of ornithine decarboxylase (ODC) and ornithine aminotransferase (OAT). We found that, outside of liver, AI was expressed in many tissues and cells such as the salivary gland, esophagus, stomach, pancreas, thymus, leukocytes, skin, preputial gland, uterus and sympathetic ganglia. The expression was much wider than that of arginase II, which was highly expressed only in the intestine and kidney. Several co-localization patterns of AI, ODC, and OAT have been found: (a) AI was co-localized with ODC alone in some tissues; (b) AI was co-localized with both OAT and ODC in a few tissues; (c) AI was not co-localized with OAT alone in any of the tissues examined; and (d) AI was not co-localized with either ODC or OAT in some tissues. In contrast, AII was not co-localized with either ODC or OAT alone in any of the tissues studied, and co-localization of AII with ODC and OAT was found only in the small intestine. The co-localization patterns of arginase, ODC, and OAT suggested that AI plays different roles in different tissues. The main roles of AI are regulation of arginine concentration by degrading arginine and production of ornithine for polyamine biosynthesis, but AI may not be the principal enzyme for regulating glutamate biosynthesis in tissues and cells.
Collapse
Affiliation(s)
- Hong Yu
- Mental Retardation Research Center, David Geffen School of Medicine at UCLA, Los Angeles, California 90095-1732, USA
| | | | | | | | | | | | | | | |
Collapse
|