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Jiachen Z, Paul Kwong Hang T, Kenneth Kak Yuen W, Vincent Chi Hang L. Pathological role of methionine in the initiation and progression of biliary atresia. Front Pediatr 2023; 11:1263836. [PMID: 37772039 PMCID: PMC10522914 DOI: 10.3389/fped.2023.1263836] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Accepted: 08/21/2023] [Indexed: 09/30/2023] Open
Abstract
Methionine (Met) is an essential amino acid, and its excessive dietary intake and/or its metabolism disturbance could lead to accumulation/depletion of hepatic Met and some of the key intermediates of these pathways, which would interfere normal liver function and would be associated with liver diseases. Biliary atresia (BA) is a life-threatening disease characterized by inflammatory fibrosclerosing changes of the intrahepatic and extrahepatic biliary systems and is the primary cause of obstructive neonatal cholestasis with a rapid course of liver failure. However, its pathogenesis remains unknown. Previous studies reported elevated Met level in patients with obstructive cholestasis, suggesting a potential link between Met and BA. This paper reviews the Met metabolism in normal conditions and its dysregulation under abnormal conditions, the possible causes of hypermethioninemia, and its connection to BA pathogenesis: Abnormal hepatic level of Met could lead to a perturbation of redox homeostasis and mitochondrial functions of hepatocytes, enhancement of viral infectivity, and dysregulation of innate and adaptative immune cells in response to infection/damage of the liver contributing to the initiation/progression of BA.
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Affiliation(s)
- Zheng Jiachen
- Department of Surgery, School of Clinical Medicine, The University of Hong Kong, Hong Kong, Hong Kong SAR, China
| | - Tam Paul Kwong Hang
- Faculty of Medicine, Macau University of Science and Technology, Macau, Macau SAR, China
| | - Wong Kenneth Kak Yuen
- Department of Surgery, School of Clinical Medicine, The University of Hong Kong, Hong Kong, Hong Kong SAR, China
- Department of Surgery, University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Lui Vincent Chi Hang
- Department of Surgery, School of Clinical Medicine, The University of Hong Kong, Hong Kong, Hong Kong SAR, China
- Dr. Li Dak-Sum Research Centre, The University of Hong Kong, Hong Kong, Hong Kong SAR, China
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2
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Majumder A. Targeting Homocysteine and Hydrogen Sulfide Balance as Future Therapeutics in Cancer Treatment. Antioxidants (Basel) 2023; 12:1520. [PMID: 37627515 PMCID: PMC10451792 DOI: 10.3390/antiox12081520] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2023] [Revised: 07/24/2023] [Accepted: 07/28/2023] [Indexed: 08/27/2023] Open
Abstract
A high level of homocysteine (Hcy) is associated with oxidative/ER stress, apoptosis, and impairment of angiogenesis, whereas hydrogen sulfide (H2S) has been found to reverse this condition. Recent studies have shown that cancer cells need to produce a high level of endogenous H2S to maintain cell proliferation, growth, viability, and migration. However, any novel mechanism that targets this balance of Hcy and H2S production has yet to be discovered or exploited. Cells require homocysteine metabolism via the methionine cycle for nucleotide synthesis, methylation, and reductive metabolism, and this pathway supports the high proliferative rate of cancer cells. Although the methionine cycle favors cancer cells for their survival and growth, this metabolism produces a massive amount of toxic Hcy that somehow cancer cells handle very well. Recently, research showed specific pathways important for balancing the antioxidative defense through H2S production in cancer cells. This review discusses the relationship between Hcy metabolism and the antiapoptotic, antioxidative, anti-inflammatory, and angiogenic effects of H2S in different cancer types. It also summarizes the historical understanding of targeting antioxidative defense systems, angiogenesis, and other protective mechanisms of cancer cells and the role of H2S production in the genesis, progression, and metastasis of cancer. This review defines a nexus of diet and precision medicine in targeting the delicate antioxidative system of cancer and explores possible future therapeutics that could exploit the Hcy and H2S balance.
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Affiliation(s)
- Avisek Majumder
- Department of Medicine, University of California, San Francisco, CA 94143, USA
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3
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Zhang HF, Klein Geltink RI, Parker SJ, Sorensen PH. Transsulfuration, minor player or crucial for cysteine homeostasis in cancer. Trends Cell Biol 2022; 32:800-814. [PMID: 35365367 PMCID: PMC9378356 DOI: 10.1016/j.tcb.2022.02.009] [Citation(s) in RCA: 41] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 02/22/2022] [Accepted: 02/28/2022] [Indexed: 12/15/2022]
Abstract
Cysteine, a thiol-containing amino acid, is crucial for the synthesis of sulfur-containing biomolecules that control multiple essential cellular activities. Altered cysteine metabolism has been linked to numerous driver oncoproteins and tumor suppressors, as well as to malignant traits in cancer. Cysteine can be acquired from extracellular sources or synthesized de novo via the transsulfuration (TSS) pathway. Limited availability of cystine in tumor interstitial fluids raises the possible dependency on de novo cysteine synthesis via TSS. However, the contribution of TSS to cancer metabolism remains highly contentious. Based on recent findings, we provide new perspectives on this crucial but understudied metabolic pathway in cancer.
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Affiliation(s)
- Hai-Feng Zhang
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada; Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC, Canada
| | - Ramon I Klein Geltink
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada; BC Children's Hospital Research Institute, Vancouver, BC, Canada
| | - Seth J Parker
- BC Children's Hospital Research Institute, Vancouver, BC, Canada; Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC, Canada
| | - Poul H Sorensen
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada; Department of Molecular Oncology, BC Cancer Research Institute, Vancouver, BC, Canada.
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4
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Zhang HF, Klein Geltink RI, Parker SJ, Sorensen PH. Transsulfuration, minor player or crucial for cysteine homeostasis in cancer. Trends Cell Biol 2022. [DOI: 10.1016/j.tcb.2022.02.009
expr 919953342 + 844571884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023]
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5
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Kovalska M, Baranovicova E, Kalenska D, Tomascova A, Adamkov M, Kovalska L, Lehotsky J. Methionine Diet Evoked Hyperhomocysteinemia Causes Hippocampal Alterations, Metabolomics Plasma Changes and Behavioral Pattern in Wild Type Rats. Int J Mol Sci 2021; 22:4961. [PMID: 34066973 PMCID: PMC8124831 DOI: 10.3390/ijms22094961] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 04/12/2021] [Accepted: 05/03/2021] [Indexed: 12/17/2022] Open
Abstract
L-methionine, an essential amino acid, plays a critical role in cell physiology. High intake and/or dysregulation in methionine (Met) metabolism results in accumulation of its intermediate(s) or breakdown products in plasma, including homocysteine (Hcy). High level of Hcy in plasma, hyperhomocysteinemia (hHcy), is considered to be an independent risk factor for cerebrovascular diseases, stroke and dementias. To evoke a mild hHcy in adult male Wistar rats we used an enriched Met diet at a dose of 2 g/kg of animal weight/day in duration of 4 weeks. The study contributes to the exploration of the impact of Met enriched diet inducing mild hHcy on nervous tissue by detecting the histo-morphological, metabolomic and behavioural alterations. We found an altered plasma metabolomic profile, modified spatial and learning memory acquisition as well as remarkable histo-morphological changes such as a decrease in neurons' vitality, alterations in the morphology of neurons in the selective vulnerable hippocampal CA 1 area of animals treated with Met enriched diet. Results of these approaches suggest that the mild hHcy alters plasma metabolome and behavioural and histo-morphological patterns in rats, likely due to the potential Met induced changes in "methylation index" of hippocampal brain area, which eventually aggravates the noxious effect of high methionine intake.
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Affiliation(s)
- Maria Kovalska
- Department of Histology and Embryology, Jessenius Faculty of Medicine, Comenius University in Bratislava, 03601 Martin, Slovakia
| | - Eva Baranovicova
- Department of Neuroscience, Biomedical Center Martin, Jessenius Faculty of Medicine, Comenius University in Bratislava, 03601 Martin, Slovakia
| | - Dagmar Kalenska
- Department of Anatomy, Jessenius Faculty of Medicine, Comenius University in Bratislava, 03601 Martin, Slovakia
| | - Anna Tomascova
- Department of Neuroscience, Biomedical Center Martin, Jessenius Faculty of Medicine, Comenius University in Bratislava, 03601 Martin, Slovakia
| | - Marian Adamkov
- Department of Histology and Embryology, Jessenius Faculty of Medicine, Comenius University in Bratislava, 03601 Martin, Slovakia
| | - Libusa Kovalska
- Clinic of Stomatology and Maxillofacial Surgery, Jessenius Faculty of Medicine, Comenius University in Bratislava, 03601 Martin, Slovakia
| | - Jan Lehotsky
- Department of Neuroscience, Biomedical Center Martin, Jessenius Faculty of Medicine, Comenius University in Bratislava, 03601 Martin, Slovakia
- Department of Medical Biochemistry, Jessenius Faculty of Medicine, Comenius University in Bratislava, 03601 Martin, Slovakia
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6
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Kalinke C, Neumsteir NV, Roberto de Oliveira P, Janegitz BC, Bonacin JA. Sensing of L-methionine in biological samples through fully 3D-printed electrodes. Anal Chim Acta 2021; 1142:135-142. [PMID: 33280691 DOI: 10.1016/j.aca.2020.10.034] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 10/15/2020] [Accepted: 10/17/2020] [Indexed: 10/23/2022]
Abstract
The variation in biomarkers levels, such as L-methionine, can be an indicator of health problems or diseases, such as metabolism, neuropsychiatric disorders, or some virus infections. Thus, the development of accurate sensors, with low-cost and rapid response has been gaining increasing importance and attractiveness for the early diagnosis of diseases. In this regard, we have proposed a method for L-methionine electrochemical detection using a low-cost and simple arrangement of 3D-printed electrodes (working, reference, and auxiliary electrodes) based on polylactic acid/graphene filament (PLA-G), in which all electrodes were printed. The working electrode was chemically and electrochemically treated, showing a high electroactive area, with graphene edge plans exposure and better electron transfer when compared to the untreated electrode. An excellent analytical performance was obtained with a sensitivity of 0.176 μAL μmol-1, a linear dynamic range of 5.0 μmol L-1- 3000 μmol L-1 and limit of detection of 1.39 μmol L-1. The proposed device was successfully applied for L-methionine detection in spiked serum samples, showing satisfactory recovery values. This indicates the potentiality of the proposed arrangement of electrodes for the L-methionine detection in biological samples at different concentration levels.
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Affiliation(s)
- Cristiane Kalinke
- Institute of Chemistry, University of Campinas, 13083-970, Campinas, SP, Brazil
| | | | - Paulo Roberto de Oliveira
- Department of Nature Science, Mathematics and Education, Federal University of São Carlos, 13600-970, Araras, SP, Brazil
| | - Bruno Campos Janegitz
- Department of Nature Science, Mathematics and Education, Federal University of São Carlos, 13600-970, Araras, SP, Brazil
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7
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Kožich V, Stabler S. Lessons Learned from Inherited Metabolic Disorders of Sulfur-Containing Amino Acids Metabolism. J Nutr 2020; 150:2506S-2517S. [PMID: 33000152 DOI: 10.1093/jn/nxaa134] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 03/12/2020] [Accepted: 04/17/2020] [Indexed: 12/16/2022] Open
Abstract
The metabolism of sulfur-containing amino acids (SAAs) requires an orchestrated interplay among several dozen enzymes and transporters, and an adequate dietary intake of methionine (Met), cysteine (Cys), and B vitamins. Known human genetic disorders are due to defects in Met demethylation, homocysteine (Hcy) remethylation, or cobalamin and folate metabolism, in Hcy transsulfuration, and Cys and hydrogen sulfide (H2S) catabolism. These disorders may manifest between the newborn period and late adulthood by a combination of neuropsychiatric abnormalities, thromboembolism, megaloblastic anemia, hepatopathy, myopathy, and bone and connective tissue abnormalities. Biochemical features include metabolite deficiencies (e.g. Met, S-adenosylmethionine (AdoMet), intermediates in 1-carbon metabolism, Cys, or glutathione) and/or their accumulation (e.g. S-adenosylhomocysteine, Hcy, H2S, or sulfite). Treatment should be started as early as possible and may include a low-protein/low-Met diet with Cys-enriched amino acid supplements, pharmacological doses of B vitamins, betaine to stimulate Hcy remethylation, the provision of N-acetylcysteine or AdoMet, or experimental approaches such as liver transplantation or enzyme replacement therapy. In several disorders, patients are exposed to long-term markedly elevated Met concentrations. Although these conditions may inform on Met toxicity, interpretation is difficult due to the presence of additional metabolic changes. Two disorders seem to exhibit Met-associated toxicity in the brain. An increased risk of demyelination in patients with Met adenosyltransferase I/III (MATI/III) deficiency due to biallelic mutations in the MATIA gene has been attributed to very high blood Met concentrations (typically >800 μmol/L) and possibly also to decreased liver AdoMet synthesis. An excessively high Met concentration in some patients with cystathionine β-synthase deficiency has been associated with encephalopathy and brain edema, and direct toxicity of Met has been postulated. In summary, studies in patients with various disorders of SAA metabolism showed complex metabolic changes with distant cellular consequences, most of which are not attributable to direct Met toxicity.
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Affiliation(s)
- Viktor Kožich
- Department of Pediatrics and Adolescent Medicine, Charles University-First Faculty of Medicine and General University Hospital, Prague, Czech Republic
| | - Sally Stabler
- Department of Medicine, University of Colorado School of Medicine Anschutz Medical Campus, Aurora, CO, USA
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8
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De Biase I, Gherasim C, La'ulu SL, Asamoah A, Longo N, Yuzyuk T. Laboratory evaluation of homocysteine remethylation disorders and classic homocystinuria: Long-term follow-up using a cohort of 123 patients. Clin Chim Acta 2020; 509:126-134. [PMID: 32533987 DOI: 10.1016/j.cca.2020.06.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Revised: 06/04/2020] [Accepted: 06/06/2020] [Indexed: 12/14/2022]
Abstract
The homocystinurias, caused by defects of remethylation and cystathionine-beta-synthase (CBS) deficiency, are characterized by elevated homocysteine and abnormal methionine levels. Various treatments, including injectable hydroxycobalamin and oral betaine, aim to reduce homocysteine toxicity and normalize methionine, but only limited biochemical data has been reported assessing biochemical response to treatment. We analyzed laboratory results in 812 plasma samples from 56 patients with remethylation disorders and 67 patients with CBS deficiency. Total plasma homocysteine (tHcys) decreased with therapy, but rarely normalized regardless of treatment, with highest levels seen in CBS (116 ± 79 μmol/L) and MTHFR (102 ± 56 μmol/L) deficiencies. In CBS deficiency, tHcys correlated positively with methionine (rs = 0.51, p < 0.0001) and inversely with cystine (rs = -0.57, p < 0.0001) consistent with a metabolic block downstream of homocysteine. In patients with remethylation disorders, methionine was mostly normal on therapy, and inversely correlated with tHcys (rs = -0.57, p < 0.0001) demonstrating effectiveness of hydroxycobalamin and/or betaine in stimulating tHcys remethylation. Betaine also significantly increased sarcosine from its pre-treatment level on average 19-fold in remethylation disorders and 3-fold in CBS deficiency, with sarcosine > 5 μmol/L being 97% sensitive and 95% specific for betaine therapy. These results show that existing therapies improve sulfur amino acid metabolism without completely normalizing it and that sarcosine can determine compliance to betaine supplementation.
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Affiliation(s)
- Irene De Biase
- Department of Pathology, University of Utah School of Medicine, Salt Lake City, UT, United States; ARUP Institute for Clinical and Experimental Pathology, Salt Lake City, UT, United States.
| | - Carmen Gherasim
- Department of Pathology, University of Utah School of Medicine, Salt Lake City, UT, United States; Department of Pathology, University of Michigan Medical School, Ann Arbor, MI, United States(1)
| | - Sonia L La'ulu
- ARUP Institute for Clinical and Experimental Pathology, Salt Lake City, UT, United States
| | - Alexander Asamoah
- Department of Pediatrics, University of Louisville, Louisville, KY, United States
| | - Nicola Longo
- Department of Pathology, University of Utah School of Medicine, Salt Lake City, UT, United States; ARUP Institute for Clinical and Experimental Pathology, Salt Lake City, UT, United States; Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, UT, United States
| | - Tatiana Yuzyuk
- Department of Pathology, University of Utah School of Medicine, Salt Lake City, UT, United States; ARUP Institute for Clinical and Experimental Pathology, Salt Lake City, UT, United States
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9
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Okawa A, Hayashi M, Inagaki J, Okajima T, Tamura T, Inagaki K. Novel method for l-methionine determination using l-methionine decarboxylase and application of the enzyme for l-homocysteine determination. Biosci Biotechnol Biochem 2020; 84:927-935. [DOI: 10.1080/09168451.2020.1715781] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Abstract
For many years, clinical studies have suggested that blood levels of l-methionine and L-homocysteine correlate with health status or homocystinuria/hypermethioninemia. l-Methionine in a solution containing 0%, 10%, or 20% human serum was detected in 10–200 µM using l-methionine decarboxylase (MetDC). Spike and recovery tests showed that the enzymatic assay could accurately and reproducibly determine the increases in l-methionine in serum samples. These results suggest that our enzymatic method using MetDC is useful for primary screening of hypermethioninemia or homocystinuria based on serum l-methionine concentration. Additionally, we confirmed that l-methionine (100 nmol) in solution was degraded to less than the detection limit by incubation at 37ºC for 10 min using 2 U of MetDC. Therefore, l-homocysteine in serum samples can be detected with equivalent sensitivity using l-methionine γ-lyase (MGL), in solutions that either did not contain l-methionine or contained l-methionine preincubated with MetDC.
Abbreviations
DTT: dithiothreitol; IPTG: isopropyl-β-d-thiogalactopyranoside; KPB: potassium phosphate buffer; MBTH: 3-methyl-2-benzothiazolinonehydrazone; mdc: the gene coding l-methionine decarboxylase; MetDC: l-methionine decarboxylase; mgl: the gene coding l-methionine γ-lyase; MGL: l-methionine γ-lyase; PLP: pyridoxal 5ʹ-phosphate
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Affiliation(s)
- Atsushi Okawa
- Department of Biofunctional Chemistry, Graduate School of Environmental and Life Science, Okayama University, Okayama, Japan
| | - Masaya Hayashi
- Department of Biofunctional Chemistry, Graduate School of Environmental and Life Science, Okayama University, Okayama, Japan
- Department of Agriculture, Kibi International University, Hyogo, Japan
| | - Junko Inagaki
- Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Toshihide Okajima
- Institute of Scientific and Industrial Research, Osaka University, Osaka, Japan
| | - Takashi Tamura
- Department of Biofunctional Chemistry, Graduate School of Environmental and Life Science, Okayama University, Okayama, Japan
| | - Kenji Inagaki
- Department of Biofunctional Chemistry, Graduate School of Environmental and Life Science, Okayama University, Okayama, Japan
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10
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Villani GR, Albano L, Caterino M, Crisci D, Di Tommaso S, Fecarotta S, Fisco MG, Frisso G, Gallo G, Mazzaccara C, Marchese E, Nolano A, Parenti G, Pecce R, Redi A, Salvatore F, Strisciuglio P, Turturo MG, Vallone F, Ruoppolo M. Hypermethioninemia in Campania: Results from 10 years of newborn screening. Mol Genet Metab Rep 2019; 21:100520. [PMID: 31641591 PMCID: PMC6796781 DOI: 10.1016/j.ymgmr.2019.100520] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Accepted: 09/10/2019] [Indexed: 11/25/2022] Open
Abstract
In the last years tandem mass spectrometry (MS/MS) has become a leading technology used for neonatal screening purposes. Newborn screening by MS/MS on dried blood spot samples (DBS) has one of its items in methionine levels: the knowledge of this parameter allows the identification of infant affected by homocystinuria (cystathionine β-synthase, CBS, deficiency) but can also lead, as side effect, to identify cases of methionine adenosyltransferase (MAT) type I/III deficiency. We started an expanded newborn screening for inborn errors of metabolism in Campania region in 2007. Here we report our ten years experience on expanded newborn screening in identifying patients affected by hypermethioninemia. During this period we screened approximately 77,000 infants and identified two cases: one case of classical homocystinuria and one patient affected by defect of MAT I/III. In this paper we describe these patients and their biochemical follow-up and review the literature concerning worldwide newborn screening reports on incidence of CBS and MAT deficiency.
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Affiliation(s)
- Guglielmo R.D. Villani
- Department of Molecular Medicine and Medical Biotechnologies, "Federico II" University, Naples, Italy
- CEINGE Biotecnologie Avanzate scarl, Naples, Italy
| | - Lucia Albano
- CEINGE Biotecnologie Avanzate scarl, Naples, Italy
| | - Marianna Caterino
- Department of Molecular Medicine and Medical Biotechnologies, "Federico II" University, Naples, Italy
- CEINGE Biotecnologie Avanzate scarl, Naples, Italy
| | | | | | - Simona Fecarotta
- Department of Translational Medical Science, Section of Pediatrics, Federico II University, Naples, Italy
| | | | - Giulia Frisso
- Department of Molecular Medicine and Medical Biotechnologies, "Federico II" University, Naples, Italy
- CEINGE Biotecnologie Avanzate scarl, Naples, Italy
| | | | - Cristina Mazzaccara
- Department of Molecular Medicine and Medical Biotechnologies, "Federico II" University, Naples, Italy
- CEINGE Biotecnologie Avanzate scarl, Naples, Italy
| | - Emanuela Marchese
- CEINGE Biotecnologie Avanzate scarl, Naples, Italy
- Dipartimento di Salute Mentale e Fisica e Medicina Preventiva, Università degli Studi della Campania L. Vanvitelli, Naples, Italy
| | - Antonio Nolano
- Department of Molecular Medicine and Medical Biotechnologies, "Federico II" University, Naples, Italy
| | - Giancarlo Parenti
- Department of Translational Medical Science, Section of Pediatrics, Federico II University, Naples, Italy
| | - Rita Pecce
- Department of Molecular Medicine and Medical Biotechnologies, "Federico II" University, Naples, Italy
- CEINGE Biotecnologie Avanzate scarl, Naples, Italy
| | - Adriana Redi
- Department of Molecular Medicine and Medical Biotechnologies, "Federico II" University, Naples, Italy
| | | | - Pietro Strisciuglio
- Department of Translational Medical Science, Section of Pediatrics, Federico II University, Naples, Italy
| | | | | | - Margherita Ruoppolo
- Department of Molecular Medicine and Medical Biotechnologies, "Federico II" University, Naples, Italy
- CEINGE Biotecnologie Avanzate scarl, Naples, Italy
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11
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George AK, Majumder A, Ice H, Homme RP, Eyob W, Tyagi SC, Singh M. Genes and genetics in hyperhomocysteinemia and the "1-carbon metabolism": implications for retinal structure and eye functions. Can J Physiol Pharmacol 2019; 98:51-60. [PMID: 31369712 DOI: 10.1139/cjpp-2019-0236] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Homocysteine (Hcy), a sulfur-containing nonproteinogenic amino acid, is generated as a metabolic intermediate. Hcy constitutes an important part of the "1-carbon metabolism" during methionine turnover. Elevated levels of Hcy known as hyperhomocysteinemia (HHcy) results from vitamin B deficiency, lack of exercise, smoking, excessive alcohol intake, high-fat and methionine-rich diet, and the underlying genetic defects. These factors directly affect the "1-carbon metabolism (methionine-Hcy-folate)" of a given cell. In fact, the Hcy levels are determined primarily by dietary intake, vitamin status, and the genetic blueprint of the susceptible individual. Although Hcy performs an important role in cellular functions, genetic alterations in any of the key enzymes responsible for the "1-carbon metabolism" could potentially upset the metabolic cycle, thus causing HHcy environment in susceptible people. As such, HHcy relates to several clinical conditions like atherosclerosis, myocardial infarction, stroke, cognitive impairment, dementia, Parkinson's disease, multiple sclerosis, epilepsy, and ocular disorders, among others. This article summarizes the findings from our laboratory and public database regarding genetics of HHcy and its effects on ocular disorders, their respective management during dysregulation of the 1-carbon metabolism.
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Affiliation(s)
- Akash K George
- Eye and Vision Science Laboratory, University of Louisville School of Medicine, Louisville, Kentucky 40202, USA.,Department of Physiology, University of Louisville School of Medicine, Louisville, Kentucky 40202, USA
| | - Avisek Majumder
- Department of Medicine, UCSF Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, San Francisco, California 94158, USA
| | - Hayley Ice
- Eye and Vision Science Laboratory, University of Louisville School of Medicine, Louisville, Kentucky 40202, USA.,Department of Physiology, University of Louisville School of Medicine, Louisville, Kentucky 40202, USA
| | - Rubens P Homme
- Eye and Vision Science Laboratory, University of Louisville School of Medicine, Louisville, Kentucky 40202, USA.,Department of Physiology, University of Louisville School of Medicine, Louisville, Kentucky 40202, USA
| | - Wintana Eyob
- College of Arts and Sciences, Case Western Reserve University, 10900 Euclid Ave, Cleveland, OH 44106, USA
| | - Suresh C Tyagi
- Department of Physiology, University of Louisville School of Medicine, Louisville, Kentucky 40202, USA
| | - Mahavir Singh
- Eye and Vision Science Laboratory, University of Louisville School of Medicine, Louisville, Kentucky 40202, USA.,Department of Physiology, University of Louisville School of Medicine, Louisville, Kentucky 40202, USA
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12
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Kar S, Kambis TN, Mishra PK. Hydrogen sulfide-mediated regulation of cell death signaling ameliorates adverse cardiac remodeling and diabetic cardiomyopathy. Am J Physiol Heart Circ Physiol 2019; 316:H1237-H1252. [PMID: 30925069 PMCID: PMC6620689 DOI: 10.1152/ajpheart.00004.2019] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Revised: 03/18/2019] [Accepted: 03/28/2019] [Indexed: 02/07/2023]
Abstract
The death of cardiomyocytes is a precursor for the cascade of hypertrophic and fibrotic remodeling that leads to cardiomyopathy. In diabetes mellitus (DM), the metabolic environment of hyperglycemia, hyperlipidemia, and oxidative stress causes cardiomyocyte cell death, leading to diabetic cardiomyopathy (DMCM), an independent cause of heart failure. Understanding the roles of the cell death signaling pathways involved in the development of cardiomyopathies is crucial to the discovery of novel targeted therapeutics and biomarkers for DMCM. Recent evidence suggests that hydrogen sulfide (H2S), an endogenous gaseous molecule, has cardioprotective effects against cell death. However, very little is known about signaling by which H2S and its downstream targets regulate myocardial cell death in the DM heart. This review focuses on H2S in the signaling of apoptotic, autophagic, necroptotic, and pyroptotic cell death in DMCM and other cardiomyopathies, abnormalities in H2S synthesis in DM, and potential H2S-based therapeutic strategies to mitigate myocardial cell death to ameliorate DMCM.
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Affiliation(s)
- Sumit Kar
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center , Omaha, Nebraska
| | - Tyler N Kambis
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center , Omaha, Nebraska
| | - Paras K Mishra
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center , Omaha, Nebraska
- Department of Anesthesiology, University of Nebraska Medical Center , Omaha, Nebraska
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13
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Kido J, Sawada T, Momosaki K, Suzuki Y, Uetani H, Kitajima M, Mitsubuchi H, Nakamura K, Matsumoto S. Neonatal methionine adenosyltransferase I/III deficiency with abnormal signal intensity in the central tegmental tract. Brain Dev 2019; 41:382-388. [PMID: 30389272 DOI: 10.1016/j.braindev.2018.10.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 10/10/2018] [Accepted: 10/17/2018] [Indexed: 11/26/2022]
Abstract
Methionine adenosyltransferase I/III (MAT I/III) deficiency is characterized by persistent hypermethioninemia. The clinical manifestations in cases with MAT I/III deficiency vary from a complete lack of symptoms to neurological problems associated with brain demyelination. We experienced a neonatal case with MAT I/III deficiency, in which severe hypermethioninemia was detected during the newborn screening test. The patient gradually showed hyperreflexia, foot clonus, and irritability from the age of 1 month onwards, and his brain magnetic resonance imaging scans showed abnormal signal intensity in the bilateral central tegmental tracts. His neurological manifestations improved after the S-adenosylmethionine (SAMe) treatment, deteriorated after discontinuation of SAMe, and re-improved owing to re-administration of SAMe. He achieved normal neurodevelopment through SAMe and methionine restriction therapy. Lack of SAMe as well as severe hypermethioninemia were thought to contribute towards the clinical psychophysical state. Moreover, impaired MAT I/III activity contributed to the development of neurological disorder from the early neonatal period.
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Affiliation(s)
- Jun Kido
- Department of Pediatrics, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Takaaki Sawada
- Department of Pediatrics, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Ken Momosaki
- Department of Pediatrics, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Yosuke Suzuki
- Department of Pediatrics, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Hiroyuki Uetani
- Department of Radiology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan
| | - Mika Kitajima
- Department of Radiology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan
| | - Hiroshi Mitsubuchi
- Department of Pediatrics, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Kimitoshi Nakamura
- Department of Pediatrics, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Shirou Matsumoto
- Department of Pediatrics, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan.
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14
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Majumder A, Singh M, George AK, Tyagi SC. Restoration of skeletal muscle homeostasis by hydrogen sulfide during hyperhomocysteinemia-mediated oxidative/ER stress condition 1. Can J Physiol Pharmacol 2018; 97:441-456. [PMID: 30422673 DOI: 10.1139/cjpp-2018-0501] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Elevated homocysteine (Hcy), i.e., hyperhomocysteinemia (HHcy), causes skeletal muscle myopathy. Among many cellular and metabolic alterations caused by HHcy, oxidative and endoplasmic reticulum (ER) stress are considered the major ones; however, the precise molecular mechanism(s) in this process is unclear. Nevertheless, there is no treatment option available to treat HHcy-mediated muscle injury. Hydrogen sulfide (H2S) is increasingly recognized as a potent anti-oxidant, anti-apoptotic/necrotic/pyroptotic, and anti-inflammatory compound and also has been shown to improve angiogenesis during ischemic injury. Patients with CBS mutation produce less H2S, making them vulnerable to Hcy-mediated cellular damage. Many studies have reported bidirectional regulation of ER stress in apoptosis through JNK activation and concomitant attenuation of cell proliferation and protein synthesis via PI3K/AKT axis. Whether H2S mitigates these detrimental effects of HHcy on muscle remains unexplored. In this review, we discuss molecular mechanisms of HHcy-mediated oxidative/ER stress responses, apoptosis, angiogenesis, and atrophic changes in skeletal muscle and how H2S can restore skeletal muscle homeostasis during HHcy condition. This review also highlights the molecular mechanisms on how H2S could be developed as a clinically relevant therapeutic option for chronic conditions that are aggravated by HHcy.
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Affiliation(s)
- Avisek Majumder
- a Department of Physiology, University of Louisville School of Medicine, Louisville, KY 40202, USA.,b Biochemistry and Molecular Genetics, University of Louisville School of Medicine, Louisville, KY 40202, USA
| | - Mahavir Singh
- a Department of Physiology, University of Louisville School of Medicine, Louisville, KY 40202, USA.,c Eye and Vision Science Laboratory, University of Louisville School of Medicine, Louisville, KY 40202, USA
| | - Akash K George
- a Department of Physiology, University of Louisville School of Medicine, Louisville, KY 40202, USA.,c Eye and Vision Science Laboratory, University of Louisville School of Medicine, Louisville, KY 40202, USA
| | - Suresh C Tyagi
- a Department of Physiology, University of Louisville School of Medicine, Louisville, KY 40202, USA
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15
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Nashabat M, Al-Khenaizan S, Alfadhel M. Methionine adenosyltransferase I/III deficiency: beyond the central nervous system manifestations. Ther Clin Risk Manag 2018; 14:225-229. [PMID: 29440907 PMCID: PMC5798556 DOI: 10.2147/tcrm.s151732] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Methionine adenosyltransferase (MAT) I/III deficiency (OMIM # 250850) is caused by a mutation in MAT1A, which encodes the two hepatic MAT isozymes I and III. With the implementation of newborn screening program to discover hypermethioninemia due to cystathionine beta-synthase deficiency, more cases are being discovered. While the majority of patients are asymptomatic, some might have central nervous system (CNS) and extra-CNS manifestations. Although neurologic manifestations and demyelination have been correlated to MAT deficiency in many reported cases, none of the previous reports focused on extra-CNS manifestations associated with the disease. This is a retrospective chart review for a 40-month-old patient with confirmed diagnosis of MAT deficiency. He was found to have a novel homozygous disease-causing variant in MAT1A (NM_000429.2) c.1081G>T (p.Val361Phe). Interestingly, our patient had an unexplained zinc and iron deficiency in addition to mild speech delay. We reviewed the literature and summarized all the reported extra-CNS manifestations. In conclusion, MAT deficiency patients should be thoroughly investigated to check for CNS and extra-CNS manifestations associated with the disease. Keeping in consideration the challenge of assuming correlation, a scrutinized look at extra-CNS manifestations and their course with time might pave the way to understanding the pathophysiology of the disease and MAT1A function.
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Affiliation(s)
- Marwan Nashabat
- King Abdullah International Medical Research Centre, King Saud bin Abdulaziz University for Health Sciences, Division of Genetics, Department of Pediatrics, King Abdulaziz Medical City, Ministry of National Guard-Health Affairs (NGHA), Riyadh, Saudi Arabia
| | - Sultan Al-Khenaizan
- Department of Dermatology, King Abdullah International Medical Research Center, King Saud bin Abdulaziz University for Health Sciences, King Abdulaziz Medical City, Ministry of National Guard-Health Affairs (NGHA), Riyadh, Saudi Arabia
| | - Majid Alfadhel
- King Abdullah International Medical Research Centre, King Saud bin Abdulaziz University for Health Sciences, Division of Genetics, Department of Pediatrics, King Abdulaziz Medical City, Ministry of National Guard-Health Affairs (NGHA), Riyadh, Saudi Arabia
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16
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Muriello MJ, Viall S, Bottiglieri T, Cusmano-Ozog K, Ferreira CR. Confirmation that MAT1A p.Ala259Val mutation causes autosomal dominant hypermethioninemia. Mol Genet Metab Rep 2017; 13:9-12. [PMID: 28748147 PMCID: PMC5512230 DOI: 10.1016/j.ymgmr.2017.07.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Revised: 07/06/2017] [Accepted: 07/07/2017] [Indexed: 11/29/2022] Open
Abstract
Methionine adenosyltransferase (MAT) I/III deficiency is an inborn error of metabolism caused by mutations in MAT1A, encoding the catalytic subunit of MAT responsible for the synthesis of S-adenosylmethionine, and is characterized by persistent hypermethioninemia. While historically considered a recessive disorder, a milder autosomal dominant form of MAT I/III deficiency occurs, though only the most common mutation p.Arg264His has ample evidence to prove dominant inheritance. We report a case of hypermethioninemia caused by the p.Ala259Val substitution and provide evidence of autosomal dominant inheritance by showing both maternal inheritance of the mutation and concomitant hypermethioninemia. The p.Ala259Val mutation falls in the dimer interface, and thus likely leads to dominant inheritance by a similar mechanism to that described in the previously reported dominant negative mutation, that is, by means of interference with subunits encoded by the wild-type allele.
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Affiliation(s)
- Michael J Muriello
- McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Sarah Viall
- Division of Genetics and Metabolism, Children's National Health System, Washington, DC, USA
| | - Teodoro Bottiglieri
- Center of Metabolomics, Institute of Metabolic Disease, Baylor Research Institute, Dallas, TX, USA
| | - Kristina Cusmano-Ozog
- Division of Genetics and Metabolism, Children's National Health System, Washington, DC, USA.,The George Washington University School of Medicine, Washington, DC, USA
| | - Carlos R Ferreira
- Division of Genetics and Metabolism, Children's National Health System, Washington, DC, USA.,National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA.,The George Washington University School of Medicine, Washington, DC, USA
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17
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McCarty MF, O'Keefe JH, DiNicolantonio JJ. Interleukin-1beta may act on hepatocytes to boost plasma homocysteine - The increased cardiovascular risk associated with elevated homocysteine may be mediated by this cytokine. Med Hypotheses 2017; 102:78-81. [PMID: 28478836 DOI: 10.1016/j.mehy.2017.03.022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Accepted: 03/11/2017] [Indexed: 11/17/2022]
Abstract
The results of multi-center trials of B vitamin supplementation reveal that, whereas moderately elevated homocysteine predicts increased risk for coronary disease, it does not play a mediating role in this regard. This essay proposes that interleukin-1beta can act on hepatocytes to suppress expression of the hepatocyte-specific forms of methionine adenosyltransferase; this in turn can be expected to decrease hepatic activity of cystathionine-β-synthase, leading to an increase in plasma homocysteine. It is further proposed that interleukin-1beta (IL-1β) is a true mediating risk factor for cardiovascular disease, and that elevated homocysteine predicts coronary disease because it can serve as a marker for increased IL-1β activity. Potent statin therapy may decrease IL-1β production by suppressing inflammasome activation - thereby accounting for the marked protection from cardiovascular events observed in the classic JUPITER study, in which the enrolled subjects had low-normal Low Density Lipoprotein cholesterol but elevated C-reactive protein.
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18
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Kumar M, Modi M, Sandhir R. Hydrogen sulfide attenuates homocysteine-induced cognitive deficits and neurochemical alterations by improving endogenous hydrogen sulfide levels. Biofactors 2017; 43:434-450. [PMID: 28394038 DOI: 10.1002/biof.1354] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2016] [Revised: 01/05/2017] [Accepted: 01/28/2017] [Indexed: 12/13/2022]
Abstract
Hyperomocysteinemia (HHcy) has been associated with mild cognitive impairment and dementia. Hydrogen sulfide (H2 S) has been suggested to be an endogenous modulator of neuronal functions. However, the effect and mechanisms involved in beneficial effect of H2 S has not been investigated in homocysteine (Hcy)-induced cognitive deficits. This study has been designed to evaluate the effect of exogenous H2 S on behavioral deficits and neurochemical alterations in HHcy animals. Hcy levels were significantly elevated in plasma, cortex, and hippocampus of Hcy administered animals. A progressive decline in memory functions and increased anxiolytic behavior was observed in HHcy animals. This was accompanied by decrease in endogenous H2 S levels along with decreased activity of cystathionase (CSE) and cystathionine β-synthase (CBS). However, a significant increase in CSE and CBS mRNAs was observed. In addition, the catecholamine and serotonin levels were reduced and the activity of monoamine oxidase A and B were increased in brain regions of HHcy animals. Haematoxylin and eosin staining revealed higher number of pyknotic cells in brain regions of HHcy animals. H2 S administration was found to lower elevated plasma and brain Hcy levels. The activities of CBS, CSE, and levels of H2 S were restored in HHcy animals administered H2 S. Exogenous H2 S also ameliorated behavioral deficits accompanied by significant increase in catecholamines. Histological analysis revealed normal cell morphology in Hcy-treated animals supplemented with H2 S. These results clearly demonstrate that the protective effect of H2 S on Hcy-induced cognitive deficits is mediated through increased catecholamine and H2 S levels thereby suggesting its beneficial role in preventing HHcy-induced neurodegeneration. © 2016 BioFactors, 43(3):434-450, 2017.
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Affiliation(s)
- Mohit Kumar
- Department of Biochemistry, Panjab University, Chandigarh, 160014, India
| | - Manish Modi
- Department of Neurology, Postgraduate Institute of Medical Education and Research, Chandigarh, 160012, India
| | - Rajat Sandhir
- Department of Biochemistry, Panjab University, Chandigarh, 160014, India
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19
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Borowczyk K, Chwatko G, Kubalczyk P, Jakubowski H, Kubalska J, Głowacki R. Simultaneous Determination of Methionine and Homocysteine by on-column derivatization with o-phtaldialdehyde. Talanta 2016; 161:917-924. [DOI: 10.1016/j.talanta.2016.09.039] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Revised: 09/14/2016] [Accepted: 09/15/2016] [Indexed: 10/21/2022]
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20
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Mechanistic basis of hypermethioninemia. Amino Acids 2016; 48:2479-2489. [PMID: 27465642 DOI: 10.1007/s00726-016-2302-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 07/19/2016] [Indexed: 02/07/2023]
Abstract
Hypermethioninemia is a condition defined as elevated plasma methionine levels and may be a consequence of different conditions that include non-genetic and genetic causes. In severe cases, hypermethioninemia may lead to development of neurological and hepatic impairments, but mechanisms are still not well elucidated. Therefore, this review aims to reunite the knowledge acquired about the methionine-induced brain and liver toxicity focusing on the results obtained by studies from patients, in vitro experiments, and in vivo animal models. In general, some studies have shown that methionine decreases Na+,K+-ATPase activity, induces oxidative stress, increases acetylcholinesterase activity, and leads to dendritic spine downregulation in brain. Concerning to liver, hypermethioninemia seems to provoke changes in cell morphology, lipid accumulation, oxidative stress, inflammation, and ATP depletion. It is possible to infer that oxidative damage is one of the most important mechanisms responsible for methionine toxicity, since different studies showed that this amino acid induces oxidative stress in brain and liver tissues. Besides, reactive oxygen species may mediate other alterations induced by methionine, such as the reduction in brain Na+,K+-ATPase activity, and liver inflammation.
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21
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Bublil EM, Majtan T, Park I, Carrillo RS, Hůlková H, Krijt J, Kožich V, Kraus JP. Enzyme replacement with PEGylated cystathionine β-synthase ameliorates homocystinuria in murine model. J Clin Invest 2016; 126:2372-84. [PMID: 27183385 DOI: 10.1172/jci85396] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Accepted: 03/22/2016] [Indexed: 01/16/2023] Open
Abstract
Homocystinuria, which typically results from cystathionine β-synthase (CBS) deficiency, is the most common defect of sulfur amino acid metabolism. CBS condenses homocysteine and serine to cystathionine that is then converted to cysteine. Individuals with homocystinuria have markedly elevated plasma levels of homocysteine and methionine and reduced concentrations of cystathionine and cysteine. Clinical disease manifestations include thromboembolism and neuropsychiatric, ocular, and skeletal complications. Here, we have shown that administration of PEGylated CBS into the circulation of homocystinuria model mice alters the extra- and intracellular equilibrium of sulfur amino acids, resulting in a decrease of approximately 75% in plasma total homocysteine (tHcy) and normalization of cysteine concentrations. Moreover, the decrease in homocysteine and the normalization of cysteine in PEGylated CBS-treated model mice were accompanied by improvement of histopathological liver symptoms and increased survival. Together, these data suggest that CBS enzyme replacement therapy (ERT) is a promising approach for the treatment of homocystinuria and that ERT for metabolic diseases may not necessitate introduction of the deficient enzyme into its natural intracellular compartment.
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22
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Kim YM, Kim JH, Choi J, Gu-Hwan K, Kim JM, Kang M, Choi IH, Cheon CK, Sohn YB, Maccarana M, Yoo HW, Lee BH. Determination of Autosomal Dominant or Recessive Methionine Adenosyltransferase I/III Deficiencies Based on Clinical and Molecular Studies. Mol Med 2016; 22:147-155. [PMID: 26933843 DOI: 10.2119/molmed.2015.00254] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Accepted: 02/09/2016] [Indexed: 11/06/2022] Open
Abstract
Methionine adenosyltransferase (MAT) I/III deficiency can be inherited as autosomal dominant (AD) or as recessive (AR) traits in which mono- or biallelic MAT1A mutations have been identified, respectively. Although most patients have benign clinical outcomes, some with the AR form have neurological deficits. Here we describe 16 Korean patients with MAT I/III deficiency from 15 unrelated families identified by newborn screening. Ten probands had the AD MAT I/III deficiency, while six had AR MAT I/III deficiency. Plasma methionine (145.7 μmol/L versus 733.2 μmol/L, P < 0.05) and homocysteine levels (12.3 μmol/L versus 18.6 μmol/L, P < 0.05) were lower in the AD type than in AR type. In addition to the only reported AD MAT1A mutation, p.Arg264His, we identified two novel AD mutations, p.Arg249Gln and p.Gly280Arg. In the AR type, four previously reported and two novel mutations, p.Arg163Trp and p.Tyr335*, were identified. No exonic deletions were found by quantitative genomic polymerase chain reaction (PCR). Three-dimensional structural prediction programs indicated that the AD-type mutations were located on the dimer interface or in the substrate binding site, hindering MAT I/III dimerization or substrate binding, respectively, whereas the AR mutations were distant from the interface or substrate binding site. These results indicate that the AD or AR MAT I/III deficiency is correlated with clinical findings, substrate levels and structural features of the mutant proteins, which is important for the neurological management and genetic counseling of the patients.
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Affiliation(s)
- Yoo-Mi Kim
- Department of Pediatrics, College of Medicine, Pusan National University Children's Hospital, Yangsan, Korea
| | - Ja Hye Kim
- Department of Pediatrics, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, Korea
| | - Jin Choi
- Department of Pediatrics, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, Korea
| | - Kim Gu-Hwan
- Medical Genetics Center, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, Korea
| | - Jae-Min Kim
- Medical Genetics Center, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, Korea
| | - Minji Kang
- Medical Genetics Center, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, Korea
| | - In-Hee Choi
- Medical Genetics Center, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, Korea
| | - Chong Kun Cheon
- Department of Pediatrics, College of Medicine, Pusan National University Children's Hospital, Yangsan, Korea
| | - Young Bae Sohn
- Department of Medical Genetics, Ajou University Hospital, Ajou University School of Medicine, Suwon, Korea
| | - Marco Maccarana
- Department of Experimental Medical Science, BMC, Lund University, Sweden
| | - Han-Wook Yoo
- Medical Genetics Center, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, Korea
| | - Beom Hee Lee
- Medical Genetics Center, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, Korea
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23
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Schweinberger BM, Turcatel E, Rodrigues AF, Wyse ATS. Gestational hypermethioninaemia alters oxidative/nitrative status in skeletal muscle and biomarkers of muscular injury and inflammation in serum of rat offspring. Int J Exp Pathol 2015; 96:277-84. [PMID: 26303039 PMCID: PMC4693554 DOI: 10.1111/iep.12136] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Accepted: 05/31/2015] [Indexed: 12/25/2022] Open
Abstract
In this study we evaluated oxidative/nitrative stress parameters (reactive oxygen species production, lipid peroxidation, sulfhydryl content, superoxide dismutase, catalase and nitrite levels), as well as total protein content in the gastrocnemius skeletal muscle of the offspring of rats that had been subjected to gestational hypermethioninaemia. The occurrence of muscular injury and inflammation was also measured by creatine kinase activity, levels of creatinine, urea and C-reactive protein and the presence of cardiac troponin I in serum. Wistar female rats (70-90 days of age) received methionine (2.68 μmol/g body weight) or saline (control) twice a day by subcutaneous injections during the gestational period (21 days). After the rats gave birth, pups were killed at the twenty-first day of life for removal of muscle and serum. Methionine treatment increased reactive oxygen species production and lipid peroxidation and decreased sulfhydryl content, antioxidant enzymes activities and nitrite levels, as well as total protein content in skeletal muscle of the offspring. Creatine kinase activity was reduced and urea and C-reactive protein levels were increased in serum of pups. These results were accompanied by reduced muscle mass. Our findings showed that maternal gestational hypermethioninaemia induced changes in oxidative/nitrative status in gastrocnemius skeletal muscle of the offspring. This may represent a mechanism which can contribute to the myopathies and loss of muscular mass that is found in some hypermethioninaemic patients. In addition, we believe that these results may be relevant as gestational hypermethioninaemia could cause damage to the skeletal muscle during intrauterine life.
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Affiliation(s)
- Bruna M. Schweinberger
- Laboratório de Neuroproteção e Doenças NeurometabólicasUniversidade Federal do Rio Grande do SulPorto AlegreBrazil
- Programa de Pós‐Graduação em Ciências Biológicas – Bioquímica. Departamento de BioquímicaInstituto de Ciências Básicas da SaúdeUniversidade Federal do Rio Grande do SulPorto AlegreBrazil
| | - Elias Turcatel
- Laboratório de Neuroproteção e Doenças NeurometabólicasUniversidade Federal do Rio Grande do SulPorto AlegreBrazil
- Programa de Pós‐Graduação em Ciências Biológicas – Bioquímica. Departamento de BioquímicaInstituto de Ciências Básicas da SaúdeUniversidade Federal do Rio Grande do SulPorto AlegreBrazil
| | - André F. Rodrigues
- Laboratório de Neuroproteção e Doenças NeurometabólicasUniversidade Federal do Rio Grande do SulPorto AlegreBrazil
- Programa de Pós‐Graduação em Ciências Biológicas – Bioquímica. Departamento de BioquímicaInstituto de Ciências Básicas da SaúdeUniversidade Federal do Rio Grande do SulPorto AlegreBrazil
| | - Angela T. S. Wyse
- Laboratório de Neuroproteção e Doenças NeurometabólicasUniversidade Federal do Rio Grande do SulPorto AlegreBrazil
- Programa de Pós‐Graduação em Ciências Biológicas – Bioquímica. Departamento de BioquímicaInstituto de Ciências Básicas da SaúdeUniversidade Federal do Rio Grande do SulPorto AlegreBrazil
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24
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Chien YH, Abdenur JE, Baronio F, Bannick AA, Corrales F, Couce M, Donner MG, Ficicioglu C, Freehauf C, Frithiof D, Gotway G, Hirabayashi K, Hofstede F, Hoganson G, Hwu WL, James P, Kim S, Korman SH, Lachmann R, Levy H, Lindner M, Lykopoulou L, Mayatepek E, Muntau A, Okano Y, Raymond K, Rubio-Gozalbo E, Scholl-Bürgi S, Schulze A, Singh R, Stabler S, Stuy M, Thomas J, Wagner C, Wilson WG, Wortmann S, Yamamoto S, Pao M, Blom HJ. Mudd's disease (MAT I/III deficiency): a survey of data for MAT1A homozygotes and compound heterozygotes. Orphanet J Rare Dis 2015; 10:99. [PMID: 26289392 PMCID: PMC4545930 DOI: 10.1186/s13023-015-0321-y] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2015] [Accepted: 08/13/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND This paper summarizes the results of a group effort to bring together the worldwide available data on patients who are either homozygotes or compound heterozygotes for mutations in MAT1A. MAT1A encodes the subunit that forms two methionine adenosyltransferase isoenzymes, tetrameric MAT I and dimeric MAT III, that catalyze the conversion of methionine and ATP to S-adenosylmethionine (AdoMet). Subnormal MAT I/III activity leads to hypermethioninemia. Individuals, with hypermethioninemia due to one of the MAT1A mutations that in heterozygotes cause relatively mild and clinically benign hypermethioninemia are currently often being flagged in screening programs measuring methionine elevation to identify newborns with defective cystathionine β-synthase activity. Homozygotes or compound heterozygotes for MAT1A mutations are less frequent. Some but not all, such individuals have manifested demyelination or other CNS abnormalities. PURPOSE OF THE STUDY The goals of the present effort have been to determine the frequency of such abnormalities, to find how best to predict whether they will occur, and to evaluate the outcomes of the variety of treatment regimens that have been used. Data have been gathered for 64 patients, of whom 32 have some evidence of CNS abnormalities (based mainly on MRI findings), and 32 do not have such evidence. RESULTS AND DISCUSSION The results show that mean plasma methionine concentrations provide the best indication of the group into which a given patient will fall: those with means of 800 μM or higher usually have evidence of CNS abnormalities, whereas those with lower means usually do not. Data are reported for individual patients for MAT1A genotypes, plasma methionine, total homocysteine (tHcy), and AdoMet concentrations, liver function studies, results of 15 pregnancies, and the outcomes of dietary methionine restriction and/or AdoMet supplementation. Possible pathophysiological mechanisms that might contribute to CNS damage are discussed, and tentative suggestions are put forth as to optimal management.
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Affiliation(s)
- Yin-Hsiu Chien
- Department of Medical Genetics and Pediatrics, National Taiwan University Hospital, Children's Hospital Building, Taipei, Taiwan
| | - Jose E Abdenur
- Division of Metabolic Disorders, CHOC Children's, Orange, CA, USA
| | - Federico Baronio
- Newborn Screening and Inborn Errors of Metabolism Regional Centre, Pediatric Endocrinology Program, Pediatric Unit, S.Orsola-Malpighi Hospital, University of Bologna, Bologna, Italy
| | - Allison Anne Bannick
- Children's Hospital of Michigan Metabolic Clinic, Detroit Medical Center, Detroit, MI, USA
| | - Fernando Corrales
- Department of Hepatology, Proteomics laboratory, Center for Applied Medical Research (CIMA), University of Navarra, IdiSNA, Pamplona, Spain
| | - Maria Couce
- Head of Metabolic Unit, Department Pediatrics, Hospital Clínico Universitario de Santiago, Santiago de Compostela, Spain
| | - Markus G Donner
- Department of Gastroenterology, Hepatology and Infectious Diseases, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Can Ficicioglu
- The Children's Hospital of Philadelphia, Division of Metabolism, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Cynthia Freehauf
- Department of Pediatrics, University of Colorado, Aurora, CO, USA
| | - Deborah Frithiof
- Department of Clinical Sciences, Pediatrics Umeå University, SE 901 85, Umeå, Sweden
| | - Garrett Gotway
- Department of Pediatrics, Division of Genetics and Metabolism; Department of Internal Medicine, Division of Clinical Genetics; and McDermott Center for Human Growth and Development, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Koichi Hirabayashi
- Department of Pediatrics, Shinshu University School of Medicine, 3-1-1, Asahi, Matsumoto, Japan
| | - Floris Hofstede
- Division of Paediatrics, Department of Metabolic Diseases, Wilhelmina Children's Hospital, University Medical Center Utrecht, Utrecht, The Netherlands
| | - George Hoganson
- Department of Pediatrics, University of Illinois at Chicago, College of Medicine, Chicago, Il, USA
| | - Wuh-Liang Hwu
- Department of Medical Genetics and Pediatrics, National Taiwan University Hospital, Children's Hospital Building, Taipei, Taiwan
| | - Philip James
- Children's Hospital Boston, Harvard Medical School, Boston, USA
| | - Sook Kim
- KSZ Children's Hospital/Korea Genetics Research Center, Jikjidaero, Heung Duck Gu, Cheng Ju City, Chung Buk, Republic of Korea
| | - Stanley H Korman
- Department of Genetics and Department of Metabolic Diseases, Hebrew University, Hadassah Medical Center, Jerusalem, Israel
| | - Robin Lachmann
- Charles Dent Metabolic Unit, National Hospital for Neurology and Neurosurgery, London, UK
| | - Harvey Levy
- Children's Hospital Boston, Harvard Medical School, Boston, USA
| | - Martin Lindner
- Department of General Pediatrics, Division of Pediatric Metabolic Medicine and Neuropediatrics, University Hospital Heidelberg, Heidelberg, Germany
- Department of Neurology, University Children's Hospital Frankfurt, Frankfurt, Germany
| | - Lilia Lykopoulou
- First Department of Pediatrics, University of Athens, Agia Sofia Children's Hospital, Athens, Greece
| | - Ertan Mayatepek
- Department of General Pediatrics, Neonatology and Pediatric Cardiology, University Children's Hospital Duesseldorf, Duesseldorf, Germany
| | - Ania Muntau
- University Children's Hospital, University Medical Center Hamburg Eppendorf, Hamburg, Germany
| | - Yoshiyuki Okano
- Department of Genetics, Hyogo College of Medicine, 1-1 Mukogawa-cho, Nishinomiya, Japan
| | - Kimiyo Raymond
- Department of Medicine and Pathology, Biochemical Genetics Laboratory, Mayo Clinic College of Medicine, Rochester, MN, USA
| | - Estela Rubio-Gozalbo
- Department of Pediatrics and Laboratory Genetic Metabolic Diseases, Maastricht University Medical Center, Maastricht, Netherlands
| | - Sabine Scholl-Bürgi
- Medical University of Innsbruck, Clinic for Pediatrics, Inherited Metabolic Disorders, Innsbruck, Austria
| | - Andreas Schulze
- Genetics and Genome Biology, Peter Gilgan Center for Research and Learning The Hospital for Sick Children, Toronto, ON, Canada
| | - Rani Singh
- Department of Human Genetics and Pediatric, Emory University, Atlanta, GA, USA
| | - Sally Stabler
- Department of Medicine, University of Colorado School of Medicine, Aurora, CO, USA
| | - Mary Stuy
- Department of Medical and Molecular Genetics Indiana University School of Medicine, Indianapolis, IN, USA
| | - Janet Thomas
- Department of Pediatrics, University of Colorado, Aurora, CO, USA
| | - Conrad Wagner
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tn, USA
| | - William G Wilson
- Division of Genetics, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Saskia Wortmann
- Nijmegen Centre for Mitochondrial Disorders (NCMD), RadboudUMC, Amalia Children's Hospital, Nijmegen, The Netherlands
| | | | - Maryland Pao
- Laboratory of Molecular Biology, National Institute of Mental Health, Bethesda, MD, USA
| | - Henk J Blom
- Laboratory for Clinical Biochemistry and Metabolism, Center for Pediatrics and Adolescent Medicine University Hospital Freiburg, 79106, Freiburg, Germany.
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Newborn Screening for Homocystinuria Revealed a High Frequency of MAT I/III Deficiency in Iberian Peninsula. JIMD Rep 2015; 20:113-20. [PMID: 25638462 DOI: 10.1007/8904_2014_400] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Revised: 12/17/2014] [Accepted: 12/18/2014] [Indexed: 01/12/2023] Open
Abstract
Homocystinuria due to cystathionine β-synthase deficiency or "classical homocystinuria" is a rare autosomal recessive condition resulting in altered sulfur metabolism with elevated methionine and homocysteine in plasma and homocystine in urine. This condition is characterized by a high clinical heterogeneity, which contributes to late clinical diagnosis, usually only made after irreversible damage has occurred. Treatment is effective if started before clinical symptoms. The analysis of methionine levels by tandem mass spectrometry (MS/MS) allows the newborn screening for homocystinuria, but false-positive results can be frequently obtained and lead to the unwanted identification of methionine adenosyl transferase (MAT I/III) deficiency. This latter condition is biochemically characterized by isolated persistent hypermethioninemia, accompanied in some individuals with slightly elevated levels of homocysteine in plasma. A dominant form of MAT I/III deficiency, associated with mutation p.R264H, seems to be very frequent in the Iberian Peninsula and usually has a clinically benign course. Both these metabolic disorders are screened in Galicia and Portugal since the introduction of the MS/MS technology, in 2000 and 2004, respectively, resulting in the identification of three patients with classical homocystinuria and 44 patients with MAT I/III deficiency. All but one heterozygous parent of MAT I/III patients, identified with the p.R264H mutation, are healthy adults around the age of 30/40. The implementation of a second-tier test for homocysteine in dried blood spots would considerably reduce the number of MAT I/III-deficient patients identified and improve the specificity and positive predictive value for classical homocystinuria screening.
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Fang P, Zhang D, Cheng Z, Yan C, Jiang X, Kruger WD, Meng S, Arning E, Bottiglieri T, Choi ET, Han Y, Yang XF, Wang H. Hyperhomocysteinemia potentiates hyperglycemia-induced inflammatory monocyte differentiation and atherosclerosis. Diabetes 2014; 63:4275-90. [PMID: 25008174 PMCID: PMC4237991 DOI: 10.2337/db14-0809] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Hyperhomocysteinemia (HHcy) is associated with increased diabetic cardiovascular diseases. However, the role of HHcy in atherogenesis associated with hyperglycemia (HG) remains unknown. To examine the role and mechanisms by which HHcy accelerates HG-induced atherosclerosis, we established an atherosclerosis-susceptible HHcy and HG mouse model. HHcy was established in mice deficient in cystathionine β-synthase (Cbs) in which the homocysteine (Hcy) level could be lowered by inducing transgenic human CBS (Tg-hCBS) using Zn supplementation. HG was induced by streptozotocin injection. Atherosclerosis was induced by crossing Tg-hCBS Cbs mice with apolipoprotein E-deficient (ApoE(-/-)) mice and feeding them a high-fat diet for 2 weeks. We demonstrated that HHcy and HG accelerated atherosclerosis and increased lesion monocytes (MCs) and macrophages (MØs) and further increased inflammatory MC and MØ levels in peripheral tissues. Furthermore, Hcy-lowering reversed circulating mononuclear cells, MC, and inflammatory MC and MC-derived MØ levels. In addition, inflammatory MC correlated positively with plasma Hcy levels and negatively with plasma s-adenosylmethionine-to-s-adenosylhomocysteine ratios. Finally, l-Hcy and d-glucose promoted inflammatory MC differentiation in primary mouse splenocytes, which was reversed by adenoviral DNA methyltransferase-1. HHcy and HG, individually and synergistically, accelerated atherosclerosis and inflammatory MC and MØ differentiation, at least in part, via DNA hypomethylation.
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Affiliation(s)
- Pu Fang
- Center for Metabolic Disease Research, School of Medicine, Temple University, Philadelphia, PA Department of Pharmacology, School of Medicine, Temple University, Philadelphia, PA
| | - Daqing Zhang
- Center for Metabolic Disease Research, School of Medicine, Temple University, Philadelphia, PA Department of Pharmacology, School of Medicine, Temple University, Philadelphia, PA
| | - Zhongjian Cheng
- Center for Metabolic Disease Research, School of Medicine, Temple University, Philadelphia, PA Department of Pharmacology, School of Medicine, Temple University, Philadelphia, PA
| | - Chenghui Yan
- Cardiovascular Research Institute and Key Laboratory of Cardiology, Shenyang Northern Hospital, Shenyang, Liaoning, P.R. China
| | - Xiaohua Jiang
- Center for Metabolic Disease Research, School of Medicine, Temple University, Philadelphia, PA Department of Pharmacology, School of Medicine, Temple University, Philadelphia, PA
| | | | - Shu Meng
- Center for Metabolic Disease Research, School of Medicine, Temple University, Philadelphia, PA Department of Pharmacology, School of Medicine, Temple University, Philadelphia, PA
| | - Erland Arning
- Institute of Metabolic Disease, Baylor Research Institute, Dallas, TX
| | | | - Eric T Choi
- Center for Metabolic Disease Research, School of Medicine, Temple University, Philadelphia, PA Department of Surgery, School of Medicine, Temple University, Philadelphia, PA
| | - Yaling Han
- Cardiovascular Research Institute and Key Laboratory of Cardiology, Shenyang Northern Hospital, Shenyang, Liaoning, P.R. China
| | - Xiao-Feng Yang
- Center for Metabolic Disease Research, School of Medicine, Temple University, Philadelphia, PA Department of Pharmacology, School of Medicine, Temple University, Philadelphia, PA Cardiovascular Research Center, School of Medicine, Temple University, Philadelphia, PA Sol Sherry Thrombosis Research Center, School of Medicine, Temple University, Philadelphia, PA
| | - Hong Wang
- Center for Metabolic Disease Research, School of Medicine, Temple University, Philadelphia, PA Department of Pharmacology, School of Medicine, Temple University, Philadelphia, PA Cardiovascular Research Center, School of Medicine, Temple University, Philadelphia, PA Sol Sherry Thrombosis Research Center, School of Medicine, Temple University, Philadelphia, PA
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Iacobazzi V, Infantino V, Castegna A, Andria G. Hyperhomocysteinemia: related genetic diseases and congenital defects, abnormal DNA methylation and newborn screening issues. Mol Genet Metab 2014; 113:27-33. [PMID: 25087163 DOI: 10.1016/j.ymgme.2014.07.016] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Revised: 07/14/2014] [Accepted: 07/14/2014] [Indexed: 01/25/2023]
Abstract
Homocysteine, a sulfur-containing amino acid derived from the methionine metabolism, is located at the branch point of two pathways of the methionine cycle, i.e. remethylation and transsulfuration. Gene abnormalities in the enzymes catalyzing reactions in both pathways lead to hyperhomocysteinemia. Hyperhomocysteinemia is associated with increased risk for congenital disorders, including neural tube closure defects, heart defects, cleft lip/palate, Down syndrome, and multi-system abnormalities in adults. Since hyperhomocysteinemia is known to affect the extent of DNA methylation, it is likely that abnormal DNA methylation during embryogenesis, may be a pathogenic factor for these congenital disorders. In this review we highlight the importance of homocysteinemia by describing the genes encoding for enzymes of homocysteine metabolism relevant to the clinical practice, especially cystathionine-β-synthase and methylenetetrahydrofolate reductase mutations, and the impairment of related metabolites levels. Moreover, a possible correlation between hyperhomocysteine and congenital disorders through the involvement of abnormal DNA methylation during embryogenesis is discussed. Finally, the relevance of present and future diagnostic tools such as tandem mass spectrometry and next generation sequencing in newborn screening is highlighted.
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Affiliation(s)
- Vito Iacobazzi
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, via Orabona 4, 70125 Bari, Italy; Center of Excellence in Comparative Genomics, University of Bari, via Orabona 4, 70125 Bari, Italy; CNR Institute of Biomembranes and Bioenergetics, Bari, Italy.
| | | | - Alessandra Castegna
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, via Orabona 4, 70125 Bari, Italy
| | - Generoso Andria
- Department of Translational Medical Sciences, Section of Pediatrics, Federico II University, Naples, Italy
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Nagao M, Tanaka T, Furujo M. Spectrum of mutations associated with methionine adenosyltransferase I/III deficiency among individuals identified during newborn screening in Japan. Mol Genet Metab 2013; 110:460-4. [PMID: 24231718 DOI: 10.1016/j.ymgme.2013.10.013] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Revised: 10/21/2013] [Accepted: 10/21/2013] [Indexed: 01/28/2023]
Abstract
Methionine adenosyltransferase I/III deficiency (MAT I/III deficiency) is an inborn error of metabolism that results in isolated persistent hypermethioninemia. Definitive diagnosis is now possible by molecular analyses of the MAT1A gene. Based on newborn screening (NBS) data collected between 2001 and 2012 in Hokkaido, Japan, the estimated incidence of MAT I/III deficiency was 1 in 107,850. 24 patients (13 males, 11 females) from 11 prefectures in Japan were referred to our laboratory for genetic diagnosis of MAT I/III deficiency. They were all found between 1992 and 2012 by the NBS program in each region. In these 24 individuals, we identified 12 distinct mutations; 14 patients were heterozygous for an R264H mutation; R264H caused an autosomal dominant and clinically benign phenotype in each case. The mutations in the other 10 patients showed autosomal recessive inheritance and included eight novel MAT1A mutations. Putative amino acid substitutions at R356 were observed with six alleles (three R356P, two R356Q, and one R356L). MAT I/III deficiency is not always benign because three of our cases involved brain demyelination or neurological complications. DNA testing early in life is recommended to prevent potential detrimental neurological manifestations.
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Affiliation(s)
- Masayoshi Nagao
- Department of Pediatrics and Clinical research, National Hospital Organization Hokkaido Medical Center, Sapporo, Japan.
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Couce ML, Bóveda MD, García-Jimémez C, Balmaseda E, Vives I, Castiñeiras DE, Fernández-Marmiesse A, Fraga JM, Mudd SH, Corrales FJ. Clinical and metabolic findings in patients with methionine adenosyltransferase I/III deficiency detected by newborn screening. Mol Genet Metab 2013; 110:218-21. [PMID: 23993429 DOI: 10.1016/j.ymgme.2013.08.003] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2013] [Revised: 08/06/2013] [Accepted: 08/06/2013] [Indexed: 11/26/2022]
Abstract
Persistent hypermethioninemia due to mutations in the MAT1A gene is often found during newborn screening (NBS) for homocystinuria due to cystathionine beta-synthase deficiency, however, outcomes and optimal management for these patients are not well established. We carried out a multicenter study of MAT I/III-deficient patients detected by NBS in four of the Spanish regional NBS programs. Data evaluated during NBS and follow-up for 18 patients included methionine and total homocysteine levels, clinical presentation parameters, genotypes, and development quotients. The birth prevalence was 1:1:22,874. At detection 16 of the 18 patients exhibited elevations of plasma methionine above 60 μmol/L (mean 99.9 ± 38 μmol/L) and the mean value in confirmation tests was 301 μmol/L (91-899) μmol/L. All patients were asymptomatic. In four patients with more markedly elevated plasma methionines (>450 μmol/L) total homocysteine values were slightly elevated (about 20 μmol/L). The average follow-up period was 3 years 7 months (range: 2-123 months). Most patients (83%) were heterozygous for the autosomal dominant Arg264His mutation and, with one exception, presented relatively low circulating methionine concentrations (<400 μM). Additional mutations identified in patients with mean confirmatory plasma methionines above 400 μM were Arg199Cys, Leu355Arg, and a novel mutation, Thr288Ala. During continued follow-up, the patients have been asymptomatic, and, to date, no therapeutic interventions have been utilized. Therefore, the currently available evidence shows that hypermethioninemia due to heterozygous MAT1A mutations such as Arg264His is a mild condition for which no treatment is necessary.
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Affiliation(s)
- María L Couce
- Unit of Diagnosis and Treatment of Congenital Metabolic Diseases, Department of Pediatrics, Hospital Clínico Universitario de Santiago de Compostela, CIBERER, Health Research Institute of Santiago de Compostela (IDIS), A Choupana, s/n, 15706 Santiago de Compostela, A Coruña, Spain
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30
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Hirabayashi K, Shiohara M, Yamada K, Sueki A, Ide Y, Takeuchi K, Hagimoto R, Kinoshita T, Yabuhara A, Mudd SH, Koike K. Neurologically normal development of a patient with severe methionine adenosyltransferase I/III deficiency after continuing dietary methionine restriction. Gene 2013; 530:104-8. [PMID: 23973726 DOI: 10.1016/j.gene.2013.08.025] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2013] [Revised: 07/15/2013] [Accepted: 08/10/2013] [Indexed: 10/26/2022]
Abstract
BACKGROUND There is not much information on established standard therapy for patients with severe methionine adenosyltransferase (MAT) I/III deficiency. CASE PRESENTATION We report a boy with MAT I/III deficiency, in whom plasma methionine and total homocysteine, and urinary homocystine were elevated. Molecular genetic studies showed him to have novel compound heterozygous mutations of the MAT1A gene: c.191T>A (p.M64K) and c.589delC (p.P197LfsX26). A low methionine milk diet was started at 31 days of age, and during continuing dietary methionine restriction plasma methionine levels have been maintained at less than 750 μmol/L. He is now 5 years old, and has had entirely normal physical growth and psychomotor development. CONCLUSIONS Although some severely MAT I/III deficient patients have developed neurologic abnormalities, we report here the case of a boy who has remained neurologically and otherwise normal for 5 years during methionine restriction, suggesting that perhaps such management, started in early infancy, may help prevent neurological complications.
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Affiliation(s)
- Koichi Hirabayashi
- Department of Pediatrics, Ina Central Hospital, Ina, Japan; Department of Pediatrics, Shinshu University School of Medicine, Matsumoto, Japan.
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31
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Metabolic profiling of total homocysteine and related compounds in hyperhomocysteinemia: utility and limitations in diagnosing the cause of puzzling thrombophilia in a family. JIMD Rep 2013; 11:149-63. [PMID: 23733603 DOI: 10.1007/8904_2013_235] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/08/2011] [Revised: 05/25/2012] [Accepted: 06/13/2012] [Indexed: 12/12/2022] Open
Abstract
We describe a family illustrating the diagnostic difficulties occurring when pyridoxine-responsive cystathionine beta-synthase (CBS) deficiency presents with thrombotic disease without associated ocular, skeletal, or CNS abnormalities, a situation increasingly recognized. This family had several thromboembolic episodes in two generations with apparently inconstant elevations of plasma total homocysteine (tHcy). When taking (sometimes even low amounts) of pyridoxine, the affected family members had low-normal tHcy and normal values for cystathionine, methionine, and cysteine. Withdrawal of vitamin therapy was necessary before lower cystathionine, elevated methionine, and decreased cysteine became apparent, a pattern suggestive of CBS deficiency, leading to the finding that the affected members were each compound heterozygotes for CBS p.G307S and p.P49L. To assist more accurate diagnosis of adults presenting with thrombophilia found to have elevated tHcy, the patterns of methionine-related metabolites in CBS-deficient patients are compared in this article to those in patients with homocysteine remethylation defects, including inborn errors of folate or cobalamin metabolism, and untreated severe cobalamin or folate deficiency. Usually serum cystathionine is low in subjects with CBS deficiency and elevated in those with remethylation defects. S-Adenosylmethionine and S-adenosylhomocysteine are often markedly elevated in CBS deficiency when tHcy is above 100 umol/L. We conclude that there are likely other undiagnosed, highly B6-responsive adult patients with CBS deficiency, and that additional testing of cystathionine, total cysteine, methionine, and S-adenosylmethionine will be helpful in diagnosing them correctly and distinguishing CBS deficiency from remethylation defects.
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Furujo M, Kinoshita M, Nagao M, Kubo T. Methionine adenosyltransferase I/III deficiency: neurological manifestations and relevance of S-adenosylmethionine. Mol Genet Metab 2012; 107:253-6. [PMID: 22951388 DOI: 10.1016/j.ymgme.2012.08.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/25/2012] [Revised: 08/03/2012] [Accepted: 08/03/2012] [Indexed: 11/17/2022]
Abstract
Methionine adenosyltransferase I/III (MAT I/III) deficiency, caused by mutations in the MAT1A gene, is an inherited metabolic disorder characterized by persistent hypermethioninemia, usually detected by newborn mass screening. There is a wide range of clinical manifestations, from completely asymptomatic to neurological problems associated with brain demyelination. Physiological role of S-adenosylmethionine (SAM), the metabolic product of methionine catalyzed by MAT, in the central nervous system has been investigated in vivo and in vitro, and case reports demonstrated an effectiveness of supplementary treatment of SAM in the improvement of neurological development and myelination. Methionine restriction can be an additional therapeutic strategy because hypermethioninemia alone may be neurotoxic; however, lowering methionine carries a risk to decrease the synthesis of SAM.
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Affiliation(s)
- Mahoko Furujo
- Department of Pediatrics, Okayama Medical Center, National Hospital Organization, Okayama, Japan.
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33
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Liu YH, Lu M, Hu LF, Wong PTH, Webb GD, Bian JS. Hydrogen sulfide in the mammalian cardiovascular system. Antioxid Redox Signal 2012; 17:141-85. [PMID: 22304473 DOI: 10.1089/ars.2011.4005] [Citation(s) in RCA: 197] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
For more than a century, hydrogen sulfide (H(2)S) has been regarded as a toxic gas. This review surveys the growing recognition of the role of H(2)S as an endogenous signaling molecule in mammals, with emphasis on its physiological and pathological pathways in the cardiovascular system. In biological fluids, H(2)S gas is a weak acid that exists as about 15% H(2)S, 85% HS(-), and a trace of S(2-). Here, we use "H(2)S" to refer to this mixture. H(2)S has been found to influence heart contractile functions and may serve as a cardioprotectant for treating ischemic heart diseases and heart failure. Alterations of the endogenous H(2)S level have been found in animal models with various pathological conditions such as myocardial ischemia, spontaneous hypertension, and hypoxic pulmonary hypertension. In the vascular system, H(2)S exerts biphasic regulation of a vascular tone with varying effects based on its concentration and in the presence of nitric oxide. Over the past decade, several H(2)S-releasing compounds (NaHS, Na(2)S, GYY4137, etc.) have been utilized to test the effect of exogenous H(2)S under different physiological and pathological situations in vivo and in vitro. H(2)S has been found to promote angiogenesis and to protect against atherosclerosis and hypertension, while excess H(2)S may promote inflammation in septic or hemorrhagic shock. H(2)S-releasing compounds and inhibitors of H(2)S synthesis hold promise in alleviating specific disease conditions. This comprehensive review covers in detail the effects of H(2)S on the cardiovascular system, especially in disease situations, and also the various underlying mechanisms.
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Affiliation(s)
- Yi-Hong Liu
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
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34
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Sen U, Sathnur PB, Kundu S, Givvimani S, Coley DM, Mishra PK, Qipshidze N, Tyagi N, Metreveli N, Tyagi SC. Increased endogenous H2S generation by CBS, CSE, and 3MST gene therapy improves ex vivo renovascular relaxation in hyperhomocysteinemia. Am J Physiol Cell Physiol 2012; 303:C41-51. [PMID: 22517358 DOI: 10.1152/ajpcell.00398.2011] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Hydrogen sulfide (H(2)S) has recently been identified as a regulator of various physiological events, including vasodilation, angiogenesis, antiapoptotic, and cellular signaling. Endogenously, H(2)S is produced as a metabolite of homocysteine (Hcy) by cystathionine β-synthase (CBS), cystathionine γ-lyase (CSE), and 3-mercaptopyruvate sulfurtransferase (3MST). Although Hcy is recognized as vascular risk factor at an elevated level [hyperhomocysteinemia (HHcy)] and contributes to vascular injury leading to renovascular dysfunction, the exact mechanism is unclear. The goal of the current study was to investigate whether conversion of Hcy to H(2)S improves renovascular function. Ex vivo renal artery culture with CBS, CSE, and 3MST triple gene therapy generated more H(2)S in the presence of Hcy, and these arteries were more responsive to endothelial-dependent vasodilation compared with nontransfected arteries treated with high Hcy. Cross section of triple gene-delivered renal arteries immunostaining suggested increased expression of CD31 and VEGF and diminished expression of the antiangiogenic factor endostatin. In vitro endothelial cell culture demonstrated increased mitophagy during high levels of Hcy and was mitigated by triple gene delivery. Also, dephosphorylated Akt and phosphorylated FoxO3 in HHcy were reversed by H(2)S or triple gene delivery. Upregulated matrix metalloproteinases-13 and downregulated tissue inhibitor of metalloproteinase-1 in HHcy were normalized by overexpression of triple genes. Together, these results suggest that H(2)S plays a key role in renovasculopathy during HHcy and is mediated through Akt/FoxO3 pathways. We conclude that conversion of Hcy to H(2)S by CBS, CSE, or 3MST triple gene therapy improves renovascular function in HHcy.
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Affiliation(s)
- Utpal Sen
- Department of Physiology and Biophysics, University of Louisville School of Medicine, Kentucky, USA.
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35
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Furujo M, Kinoshita M, Nagao M, Kubo T. S-adenosylmethionine treatment in methionine adenosyltransferase deficiency, a case report. Mol Genet Metab 2012; 105:516-8. [PMID: 22178350 DOI: 10.1016/j.ymgme.2011.11.192] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2011] [Revised: 11/18/2011] [Accepted: 11/18/2011] [Indexed: 11/16/2022]
Abstract
Reported is a female patient with methionine adenosyltransferase I/III (MAT I/III) deficiency, who was found to have pronounced hypermethioninemia on newborn mass spectroscopy screening, and had two compound heterozygous missense mutations in the gene encoding human MAT1A protein. Hypermethioninemia persisted and her mental development was deficient. At 4 years and 8 months, we started with the supplementary treatment of S-adenosylmethionine, the metabolic product of methionine catalyzed by MAT, which was effective in her neurological development.
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Affiliation(s)
- Mahoko Furujo
- Department of Pediatrics, National Hospital Organization, Okayama Medical Center, Okayama, Japan.
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36
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Martins E, Marcão A, Bandeira A, Fonseca H, Nogueira C, Vilarinho L. Methionine Adenosyltransferase I/III Deficiency in Portugal: High Frequency of a Dominantly Inherited Form in a Small Area of Douro High Lands. JIMD Rep 2012; 6:107-12. [PMID: 23430947 DOI: 10.1007/8904_2011_124] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2011] [Revised: 12/10/2011] [Accepted: 12/14/2011] [Indexed: 01/11/2023] Open
Abstract
Methionine adenosyltransferase deficiency (MAT I/III deficiency) is an inborn error of metabolism resulting in isolated hypermethioninemia, and usually inherited as an autosomal recessive trait, although a dominant form has been reported in several families.During the last 6 years, approximately 520,000 newborns were screened in the Portuguese Newborn Screening Laboratory by MS/MS, and 21 cases of persistent hypermethioninemia were found. One case was confirmed to be a deficiency of cystathionine β-synthase and 20 cases were confirmed by MAT1A gene analysis to have an elevation of methionine due to MAT I/III deficiency, which indicates an incidence for this condition of 1/26,000. Twelve of the MAT I/III deficient newborns, belonging to 11 families, were identified in the northern region of Portugal and sent to the same treatment center, where they are under follow-up. Clinical, biochemical, and genetic characteristics of individuals from these 11 families are presented. Plasma methionine and homocysteine concentrations were found to be moderately increased in all newborns, and molecular analysis revealed that they all were heterozygous for R264H mutation. Normal growth, development, and neurological examination were observed in all cases, and cerebral MRI performed in six cases revealed myelination abnormalities in one case. Plasma methionine concentration for all 12 cases was always below 300 μM, and they are all on a normal diet for their age.
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Affiliation(s)
- E Martins
- Hospital de Crianças Maria Pia, Centro Hospitalar do Porto, Rua da Boavista, 827, 4050-111, Porto, Portugal,
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Mudd SH, Wagner C, Luka Z, Stabler SP, Allen RH, Schroer R, Wood T, Wang J, Wong LJ. Two patients with hepatic mtDNA depletion syndromes and marked elevations of S-adenosylmethionine and methionine. Mol Genet Metab 2012; 105:228-36. [PMID: 22137549 PMCID: PMC3264801 DOI: 10.1016/j.ymgme.2011.11.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/22/2011] [Revised: 11/07/2011] [Accepted: 11/07/2011] [Indexed: 02/07/2023]
Abstract
This paper reports studies of two patients proven by a variety of studies to have mitochondrial depletion syndromes due to mutations in either their MPV17 or DGUOK genes. Each was initially investigated metabolically because of plasma methionine concentrations as high as 15-21-fold above the upper limit of the reference range, then found also to have plasma levels of S-adenosylmethionine (AdoMet) 4.4-8.6-fold above the upper limit of the reference range. Assays of S-adenosylhomocysteine, total homocysteine, cystathionine, sarcosine, and other relevant metabolites and studies of their gene encoding glycine N-methyltransferase produced evidence suggesting they had none of the known causes of elevated methionine with or without elevated AdoMet. Patient 1 grew slowly and intermittently, but was cognitively normal. At age 7 years he was found to have hepatocellular carcinoma, underwent a liver transplant and died of progressive liver and renal failure at age almost 9 years. Patient 2 had a clinical course typical of DGUOK deficiency and died at age 8 ½ months. Although each patient had liver abnormalities, evidence is presented that such abnormalities are very unlikely to explain their elevations of AdoMet or the extent of their hypermethioninemias. A working hypothesis is presented suggesting that with mitochondrial depletion the normal usage of AdoMet by mitochondria is impaired, AdoMet accumulates in the cytoplasm of affected cells poor in glycine N-methyltransferase activity, the accumulated AdoMet causes methionine to accumulate by inhibiting activity of methionine adenosyltransferase II, and that both AdoMet and methionine consequently leak abnormally into the plasma.
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Affiliation(s)
- S Harvey Mudd
- Laboratory of Molecular Biology, National Institute of Mental Health, Bethesda, MD 20892, USA.
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Mudd SH. Hypermethioninemias of genetic and non-genetic origin: A review. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2011; 157C:3-32. [PMID: 21308989 DOI: 10.1002/ajmg.c.30293] [Citation(s) in RCA: 147] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
This review covers briefly the major conditions, genetic and non-genetic, sometimes leading to abnormally elevated methionine, with emphasis on recent developments. A major aim is to assist in the differential diagnosis of hypermethioninemia. The genetic conditions are: (1) Homocystinuria due to cystathionine β-synthase (CBS) deficiency. At least 150 different mutations in the CBS gene have been identified since this deficiency was established in 1964. Hypermethioninemia is due chiefly to remethylation of the accumulated homocysteine. (2) Deficient activity of methionine adenosyltransferases I and III (MAT I/III), the isoenzymes the catalytic subunit of which are encoded by MAT1A. Methionine accumulates because its conversion to S-adenosylmethionine (AdoMet) is impaired. (3) Glycine N-methyltrasferase (GNMT) deficiency. Disruption of a quantitatively major pathway for AdoMet disposal leads to AdoMet accumulation with secondary down-regulation of methionine flux into AdoMet. (4) S-adenosylhomocysteine (AdoHcy) hydrolase (AHCY) deficiency. Not being catabolized normally, AdoHcy accumulates and inhibits many AdoMet-dependent methyltransferases, producing accumulation of AdoMet and, thereby, hypermethioninemia. (5) Citrin deficiency, found chiefly in Asian countries. Lack of this mitochondrial aspartate-glutamate transporter may produce (usually transient) hypermethioninemia, the immediate cause of which remains uncertain. (6) Fumarylacetoacetate hydrolase (FAH) deficiency (tyrosinemia type I) may lead to hypermethioninemia secondary either to liver damage and/or to accumulation of fumarylacetoacetate, an inhibitor of the high K(m) MAT. Additional possible genetic causes of hypermethioninemia accompanied by elevations of plasma AdoMet include mitochondrial disorders (the specificity and frequency of which remain to be elucidated). Non-genetic conditions include: (a) Liver disease, which may cause hypermethioninemia, mild, or severe. (b) Low-birth-weight and/or prematurity which may cause transient hypermethioninemia. (c) Ingestion of relatively large amounts of methionine which, even in full-term, normal-birth-weight babies may cause hypermethioninemia.
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Affiliation(s)
- S Harvey Mudd
- Laboratory of Molecular Biology, National Institute of Mental Health, Bethesda, MD, USA.
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Maclean KN, Sikora J, Kožich V, Jiang H, Greiner LS, Kraus E, Krijt J, Overdier KH, Collard R, Brodsky GL, Meltesen L, Crnic LS, Allen RH, Stabler SP, Elleder M, Rozen R, Patterson D, Kraus JP. A novel transgenic mouse model of CBS-deficient homocystinuria does not incur hepatic steatosis or fibrosis and exhibits a hypercoagulative phenotype that is ameliorated by betaine treatment. Mol Genet Metab 2010; 101:153-62. [PMID: 20638879 PMCID: PMC2954364 DOI: 10.1016/j.ymgme.2010.06.010] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2010] [Revised: 06/16/2010] [Accepted: 06/16/2010] [Indexed: 12/02/2022]
Abstract
Cystathionine beta-synthase (CBS) catalyzes the condensation of homocysteine (Hcy) and serine to cystathionine, which is then hydrolyzed to cysteine by cystathionine gamma-lyase. Inactivation of CBS results in CBS-deficient homocystinuria more commonly referred to as classical homocystinuria, which, if untreated, results in mental retardation, thromboembolic complications, and a range of connective tissue disorders. The molecular mechanisms that underlie the pathology of this disease are poorly understood. We report here the generation of a new mouse model of classical homocystinuria in which the mouse cbs gene is inactivated and that exhibits low-level expression of the human CBS transgene under the control of the human CBS promoter. This mouse model, designated "human only" (HO), exhibits severe elevations in both plasma and tissue levels of Hcy, methionine, S-adenosylmethionine, and S-adenosylhomocysteine and a concomitant decrease in plasma and hepatic levels of cysteine. HO mice exhibit mild hepatopathy but, in contrast to previous models of classical homocystinuria, do not incur hepatic steatosis, fibrosis, or neonatal death with approximately 90% of HO mice living for at least 6months. Tail bleeding determinations indicate that HO mice are in a hypercoagulative state that is significantly ameliorated by betaine treatment in a manner that recapitulates the disease as it occurs in humans. Our findings indicate that this mouse model will be a valuable tool in the study of pathogenesis in classical homocystinuria and the rational design of novel treatments.
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Affiliation(s)
- Kenneth N Maclean
- Departments of Pediatrics and Medicine, University of Colorado School of Medicine, Aurora, CO 80045, USA.
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40
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Fernández-Irigoyen J, Santamaría E, Chien YH, Hwu WL, Korman SH, Faghfoury H, Schulze A, Hoganson GE, Stabler SP, Allen RH, Wagner C, Mudd SH, Corrales FJ. Enzymatic activity of methionine adenosyltransferase variants identified in patients with persistent hypermethioninemia. Mol Genet Metab 2010; 101:172-7. [PMID: 20675163 DOI: 10.1016/j.ymgme.2010.07.009] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/25/2010] [Revised: 07/08/2010] [Accepted: 07/08/2010] [Indexed: 01/12/2023]
Abstract
Methionine adenosyltransferases (MAT's) are central enzymes in living organisms that have been conserved with a high degree of homology among species. In the liver, MAT I and III, tetrameric and dimeric isoforms of the same catalytic subunit encoded by the gene MAT1A, account for the predominant portion of total body synthesis of S-adenosylmethionine (SAM), a versatile sulfonium ion-containing molecule involved in a variety of vital metabolic reactions and in the control of hepatocyte proliferation and differentiation. During the past 15years 28 MAT1A mutations have been described in patients with elevated plasma methionines, total homocysteines at most only moderately elevated, and normal levels of tyrosine and other aminoacids. In this study we describe functional analyses that determine the MAT and tripolyphosphatase (PPPase) activities of 18 MAT1A variants, six of them novel, and none of them previously assayed for activity. With the exception of G69S and Y92H, all recombinant proteins showed impairment (usually severe) of MAT activity. Tripolyphosphate (PPPi) hydrolysis was decreased only in some mutant proteins but, when it was decreased MAT activity was always also impaired.
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Affiliation(s)
- Joaquín Fernández-Irigoyen
- Division of Hepatology and Gene Therapy, Proteomics Unit, Center for Applied Medical Research (CIMA), University of Navarra, 31008 Pamplona, Spain
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Abstract
Hyperhomocysteinemia, an increased level of plasma homocysteine, is an independent risk factor for the development of premature arterial fibrosis with peripheral and cerebro-vascular, neurogenic and hypertensive heart disease, coronary occlusion and myocardial infarction, as well as venous thromboembolism. It is reported that hyperhomocysteinemia causes vascular dysfunction by two major routes: (1) increasing blood pressure and, (2) impairing the vasorelaxation activity of endothelial-derived nitric oxide. The homocysteine activates metalloproteinases and induces collagen synthesis and causes imbalances of elastin/collagen ratio which compromise vascular elastance. The metabolites from hyperhomocysteinemic endothelium could modify components of the underlying muscle cells, leading to vascular dysfunction and hypertension. Homocysteine metabolizes in the body to produce H(2)S, which is a strong antioxidant and vasorelaxation factor. At an elevated level, homocysteine inactivates proteins by homocysteinylation including its endogenous metabolizing enzyme, cystathionine gamma-lyase. Thus, reduced production of H(2)S during hyperhomocysteinemia exemplifies hypertension and vascular diseases. In light of the present information, this review focuses on the mechanism of hyperhomocysteinemia-associated hypertension and highlights the novel modulatory role of H(2)S to ameliorate hypertension.
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Affiliation(s)
- Utpal Sen
- Department of Physiology & Biophysics, University of Louisville School of Medicine, 500 South Preston Street, Louisville, KY 40202, USA.
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Ishii I, Akahoshi N, Yamada H, Nakano S, Izumi T, Suematsu M. Cystathionine gamma-Lyase-deficient mice require dietary cysteine to protect against acute lethal myopathy and oxidative injury. J Biol Chem 2010; 285:26358-68. [PMID: 20566639 DOI: 10.1074/jbc.m110.147439] [Citation(s) in RCA: 188] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Cysteine is considered a nonessential amino acid in mammals as it is synthesized from methionine via trans-sulfuration. However, premature infants or patients with hepatic failure may require dietary cysteine due to a lack of cystathionine gamma-lyase (CTH), a key trans-sulfuration enzyme. Here, we generated CTH-deficient (Cth(-/-)) mice as an animal model of cystathioninemia/cystathioninuria. Cth(-/-) mice developed normally in general but displayed hypercystathioninemia/hyperhomocysteinemia though not hypermethioninemia. When fed a low cyst(e)ine diet, Cth(-/-) mice showed acute skeletal muscle atrophy (myopathy) accompanied by enhanced gene expression of asparagine synthetase and reduced contents of glutathione in livers and skeletal muscles, and intracellular accumulation of LC3 and p62 in skeletal myofibers; they finally died of severe paralysis of the extremities. Cth(-/-) hepatocytes required cystine in a culture medium and showed greater sensitivity to oxidative stress. Cth(-/-) mice exhibited systemic vulnerability to oxidative injury, which became more prominent when they were fed the low cyst(e)ine diet. These results reveal novel roles of trans-sulfuration previously unrecognized in mice lacking another trans-sulfuration enzyme cystathionine beta-synthase (Cbs(-/-)). Because Cbs(-/-) mice display hyperhomocysteinemia and hypermethioninemia, our results raise questions against the homocysteine-based etiology of CBS deficiency and the current newborn screening for homocysteinemia using Guthrie's method, which detects hypermethioninemia.
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Affiliation(s)
- Isao Ishii
- Department of Biochemistry and Integrative Medical Biology, Keio University School of Medicine, Shinjuku, Tokyo 160-8582, Japan.
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Sen U, Munjal C, Qipshidze N, Abe O, Gargoum R, Tyagi SC. Hydrogen sulfide regulates homocysteine-mediated glomerulosclerosis. Am J Nephrol 2010; 31:442-55. [PMID: 20395677 DOI: 10.1159/000296717] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2010] [Accepted: 03/08/2010] [Indexed: 12/19/2022]
Abstract
BACKGROUND/AIMS In this study we tested the hypothesis that H(2)S regulates collagen deposition, matrix metalloproteinases (MMP) and inflammatory molecules during hyperhomocysteinemia (HHcy) resulting in attenuation of glomerulosclerosis and improved renal function. MATERIALS AND METHODS A genetic model of HHcy, cystathionine beta-synthase heterozygous (CBS+/-) and wild-type (WT) 2-kidney (2K) mice were used in this study and supplemented with or without NaHS (30 micromol/l, H(2)S donor) in drinking water for 8 weeks. To expedite the renal damage associated with HHcy, uninephrectomized (1K) mice of similar groups were also used. RESULTS Results demonstrated that NAD(P)H oxidase (p47(phox)subunit) and blood pressure were upregulated in WT 1K, CBS+/- 2K and CBS+/- 1K mice with downregulation of H(2)S production and reduced glomerular filtration rate. These changes were normalized with H(2)S supplementation. Both pro- and active MMP-2 and -9 and collagen protein expressions and glomerular depositions were also upregulated in WT 1K, CBS+/- 2K and CBS+/- 1K mice. Increased expressions of inflammatory molecules, intercellular cell adhesion molecule-1 and vascular cell adhesion molecule-1, as well as increased macrophage infiltration, were detected in WT 1K, CBS+/- 2K and CBS+/- 1K mice. These changes were ameliorated with H(2)S supplementation. CONCLUSION Together, these results suggest that increased oxidative stress and decreased H(2)S in HHcy causes matrix remodeling and inflammation resulting in glomerulosclerosis and reduced renal function.
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Affiliation(s)
- Utpal Sen
- Department of Physiology and Biophysics, University of Louisville School of Medicine, Louisville, KY 40202, USA. u0sen001 @ louisville.edu
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44
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Barić I. Inherited disorders in the conversion of methionine to homocysteine. J Inherit Metab Dis 2009; 32:459-71. [PMID: 19585268 DOI: 10.1007/s10545-009-1146-4] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2009] [Revised: 04/20/2009] [Accepted: 05/05/2009] [Indexed: 12/15/2022]
Abstract
During the last decade much important new information relating to the metabolic pathway from methionine to homocysteine has been gained. Interest has been stimulated by the discovery of two novel disorders, glycine N-methyltransferase deficiency and S-adenosylhomocysteine hydrolase deficiency. Another disorder in this pathway, methionine adenosyltransferase deficiency, has been increasingly detected, thanks to the expansion of newborn screening programmes by tandem mass spectrometry technology. These significant steps allow important insight into the pathogenesis of these three disorders, as well as into the mechanisms of damage to various organs (liver, brain, muscle) and point to the relevance of these disorders for crucial biological processes such as methylation, transsulfuration or carcinogenesis in mammals, the pathogenesis of numerous pathological conditions, in particular those associated with hyperhomocysteinaemia, the action and possible toxicity of some drugs or consequences of nutritional variations. This review summarizes current knowledge of three inherited disorders in this metabolic pathway and draws attention to their much broader significance for human health and understanding of important biological processes.
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Affiliation(s)
- Ivo Barić
- Department of Pediatrics, University Hospital Center and School of Medicine, Zagreb, Croatia.
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45
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Couce ML, Bóveda MD, Castiñeiras DE, Corrales FJ, Mora MI, Fraga JM, Mudd SH. Hypermethioninaemia due to methionine adenosyltransferase I/III (MAT I/III) deficiency: diagnosis in an expanded neonatal screening programme. J Inherit Metab Dis 2008; 31 Suppl 2:S233-9. [PMID: 18500573 DOI: 10.1007/s10545-008-0811-3] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2007] [Revised: 01/18/2008] [Accepted: 03/12/2008] [Indexed: 11/29/2022]
Abstract
The Expanded Newborn Screening Program (MS/MS) in the region of Galicia (NW Spain) was initiated in 2000 and includes the measurement of methionine levels in dried blood spots. Between June 2000 and June 2007, 140 818 newborns were analysed, and six cases of persistent hypermethioninaemia were detected: one homocystinuria due to cystathionine β-synthase (CβS) deficiency, and five methionine adenosyltransferase I/III (MAT I/III) deficiencies. The five cases of MAT I/III deficiency represent an incidence of 1/28 163 newborns. In these five patients, methionine levels in dried blood spots ranged from 50 to 147 μmol/L. At confirmation of the persistence of the hypermethioninaemia in a subsequent plasma sample, plasma methionine concentrations were moderately elevated in 4 of the 5 patients (mean 256 μmol/L), while total homocysteine (tHcy) was normal; the remaining patient showed plasma methionine of 573 μmol/L and tHcy of 22.8 μmol/L. All five patients were heterozygous for the same dominant mutation, R264H in the MAT1A gene. With a diet not exceeding recommended protein requirements for their age, all patients maintained methionine levels below 300 μmol/L. Currently, with a mean of 2.5 years since diagnosis, the patients are asymptomatic and show developmental quotients within the normal range. Our results show a rather high frequency of hypermethioninaemia due to MAT I/III deficiency in the Galician neonatal population, indicating a need for further studies to evaluate the impact of persistent isolated hypermethioninaemia in neonatal screening programmes.
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Affiliation(s)
- M L Couce
- Unidad de Trastornos Metabólicos, Departamento de Pediatría, Hospital Clínico Universitario, Santiago de Compostela, Spain
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Abstract
Two superimposed metabolic sequences, transsulfuration and the methionine/homocysteine cycle, form the pathway for methionine metabolism in mammalian liver. This combined pathway was formulated first to explain observations in subjects with homocystinuria caused by cystathionine synthase deficiency. Since that time additional inborn errors have been discovered, and currently we know of human subjects with isolated defects in all of the reactions of the combined pathway with only one exception: betaine homocysteine methyltransferase. Studies of these inborn errors have contributed significantly to our knowledge of human methionine metabolism and to the clinical consequences of impaired metabolism. Transsulfuration appears to function primarily for the metabolism of excess methionine, and each of the 5 defects in this pathway results in the accumulation of 1 or more of the normal metabolites. Thus, studies of these disorders may provide insight into both the potential pathological sequelae of nutritional methionine excess as well as whether laboratory testing allows the detection of excess.
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Affiliation(s)
- James D Finkelstein
- Department of Veterans Affairs Medical Center and Department of Medicine, George Washington University, Washington DC 20422, USA.
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47
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Doshi S, McDowell I, Goodfellow J, Stabler S, Boger R, Allen R, Newcombe R, Lewis M, Moat S. Relationship between S-adenosylmethionine, S-adenosylhomocysteine, asymmetric dimethylarginine, and endothelial function in healthy human subjects during experimental hyper- and hypohomocysteinemia. Metabolism 2005; 54:351-60. [PMID: 15736113 DOI: 10.1016/j.metabol.2004.09.015] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Experimental hyperhomocysteinemia after an oral methionine or homocysteine load is associated with impaired nitric oxide-dependent vasodilatation in healthy human beings. However, it remains unproven that this effect is mediated by elevations in plasma homocysteine. There is evidence that an increase in plasma homocysteine may increase the formation of asymmetric dimethylarginine (ADMA), an inhibitor of nitric oxide synthase. The methyl groups within ADMA are derived from the conversion of S -adenosylmethionine to S -adenosylhomocysteine intermediates in the methionine/homocysteine pathway. No previous study has assessed the role of methylation status, its impact on ADMA formation, and their association with endothelial function in healthy human beings. In a randomized, placebo-controlled, crossover study, 10 healthy subjects (mean age, 29.1 +/- 3.9 years) were administered an oral dose of methionine (0.1 g/kg), l -homocysteine (0.01 g/kg), N-acetylcysteine (NAC) (0.1 g/kg), or placebo. Endothelial function as assessed by flow-mediated dilatation (FMD) of the brachial artery was impaired after both the methionine and homocysteine load compared with placebo at 4 hours (36 +/- 15, 67 +/- 23 vs 219 +/- 26 microm, respectively, P < .001). N-Acetylcysteine had no effect on flow-mediated dilatation. Plasma total homocysteine was significantly elevated at 4 hours after methionine (23.1 +/- 6.2) and homocysteine (41.5 +/- 8.9) loading, but significantly reduced after NAC 2.4 +/- 0.6 vs 7.1 +/- 2.1 micromol/L in the placebo (P < .001). Plasma S-adenosylmethionine/S-adenosylhomocysteine ratio was significantly (P < .001) increased at 4 hours after methionine (10.9 +/- 0.7) compared with homocysteine (5.4 +/- 0.4), NAC (5.0 +/- 0.3), and placebo (6.0 +/- 0.5). Plasma ADMA concentrations were not altered by any intervention. Our results suggest that endothelial dysfunction due to methionine or homocysteine loading is not associated with an increase in plasma ADMA or a disruption in methylation status.
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Affiliation(s)
- Sagar Doshi
- Cardiovascular Sciences Research Group, Wales Heart Research Institute, University of Wales College of Medicine, Heath Park CF14 4XN Cardiff, UK
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Linnebank M, Lagler F, Muntau AC, Röschinger W, Olgemöller B, Fowler B, Koch HG. Methionine adenosyltransferase (MAT) I/III deficiency with concurrent hyperhomocysteinaemia: two novel cases. J Inherit Metab Dis 2005; 28:1167-8. [PMID: 16435220 DOI: 10.1007/s10545-005-4497-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
This study reports three novel mutations of the methionine adenosyltransferase (MAT) lA gene and confirms that hyperhomocysteinaemia may be a characteristic finding in MAT I/III deficiency. Thus, MAT I/III deficiency is important in the differential diagnoses of hyperhomocysteinaemia, which may lead to clinical complications of MAT I/III deficiency.
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Affiliation(s)
- M Linnebank
- Children's Hospital, University of Münster, Münster, Germany.
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49
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Barić I, Cuk M, Fumić K, Vugrek O, Allen RH, Glenn B, Maradin M, Pazanin L, Pogribny I, Rados M, Sarnavka V, Schulze A, Stabler S, Wagner C, Zeisel SH, Mudd SH. S-Adenosylhomocysteine hydrolase deficiency: a second patient, the younger brother of the index patient, and outcomes during therapy. J Inherit Metab Dis 2005; 28:885-902. [PMID: 16435181 PMCID: PMC2441944 DOI: 10.1007/s10545-005-0192-9] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2005] [Accepted: 09/02/2005] [Indexed: 10/25/2022]
Abstract
S-Adenosylhomocysteine (AdoHcy) hydrolase deficiency has been proven in a human only once, in a recently described Croatian boy. Here we report the clinical course and biochemical abnormalities of the younger brother of this proband. This younger brother has the same two mutations in the gene encoding AdoHcy hydrolase, and has been monitored since birth. We report, as well, outcomes during therapy for both patients. The information obtained suggests that the disease starts in utero and is characterized primarily by neuromuscular symptomatology (hypotonia, sluggishness, psychomotor delay, absent tendon reflexes, delayed myelination). The laboratory abnormalities are markedly increased creatine kinase and elevated aminotransferases, as well as specific amino acid aberrations that pinpoint the aetiology. The latter include, most importantly, markedly elevated plasma AdoHcy. Plasma S-adenosylmethionine (AdoMet) is also elevated, as is methionine (although the hypermethioninaemia may be absent or nonsignificant in the first weeks of life). The disease seems to be at least to some extent treatable, as shown by improved myelination and psychomotor development during dietary methionine restriction and supplementation with creatine and phosphatidylcholine.
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Affiliation(s)
- I Barić
- Department of Pediatrics, University Hospital Center and School of Medicine, Zagreb, Croatia.
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50
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Stipanuk MH. Sulfur amino acid metabolism: pathways for production and removal of homocysteine and cysteine. Annu Rev Nutr 2004; 24:539-77. [PMID: 15189131 DOI: 10.1146/annurev.nutr.24.012003.132418] [Citation(s) in RCA: 687] [Impact Index Per Article: 34.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Tissue concentrations of both homocysteine (Hcy) and cysteine (Cys) are maintained at low levels by regulated production and efficient removal of these thiols. The regulation of the metabolism of methionine and Cys is discussed from the standpoint of maintaining low levels of Hcy and Cys while, at the same time, ensuring an adequate supply of these thiols for their essential functions. S-Adenosylmethionine coordinately regulates the flux through remethylation and transsulfuration, and glycine N-methyltransferase regulates flux through transmethylation and hence the S-adenosylmethionine/S-adenosylhomocysteine ratio. Cystathionine beta-synthase activity is also regulated in response to the redox environment, and transcription of the gene is hormonally regulated in response to fuel supply (insulin, glucagon, and glucocorticoids). The H2S-producing capacity of cystathionine gamma-lyase may be regulated in response to nitric oxide. Cys is substrate for a variety of anabolic and catabolic enzymes. Its concentration is regulated primarily by hepatic Cys dioxygenase; the level of Cys dioxygenase is upregulated in a Cys-responsive manner via a decrease in the rate of polyubiquitination and, hence, degradation by the 26S proteasome.
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Affiliation(s)
- Martha H Stipanuk
- Division of Nutritional Sciences, Cornell University, Ithaca, New York 14853, USA.
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