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Xu H, Feng P, Sun Y, Wu D, Wang D, Wu L, Peng H, Li H. Plasma trimethylamine N-oxide metabolites in the second trimester predict the risk of hypertensive disorders of pregnancy: a nested case-control study. Hypertens Res 2024; 47:778-789. [PMID: 38177285 DOI: 10.1038/s41440-023-01563-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 12/10/2023] [Accepted: 12/10/2023] [Indexed: 01/06/2024]
Abstract
The relationship between gut microbiota products trimethylamine oxide (TMAO) and related metabolites including betaine, choline and L-carnitine and hypertensive disorders of pregnancy (HDP) is unclear. In order to examine whether plasma TMAO and related metabolites predict the risk of HDP, a nested case-control study was conducted in Chinese women based on a prospective cohort including 9447 participants. 387 pairs of pregnant women (n = 774) were matched and their plasma TMAO, betaine, choline, and L-carnitine at 16-20 gestational weeks were measured by liquid chromatography-mass spectrometry. Odds ratio (OR) and the 95% confidence interval (95% CI) were calculated using the conditional logistic regression, to examine the association between TMAO metabolites and HDP. The findings showed that higher plasma betaine (≥24.94 μmol/L) was associated with a decreased risk of HDP and its subtype gestational hypertension (GH), with adjusted ORs of 0.404 (95% CI: 0.226-0.721) and 0.293 (95% CI: 0.134-0.642), respectively. Higher betaine/choline ratio (>2.64) was associated with a lower risk of HDP and its subtype preeclampsia or chronic hypertension with superimposed preeclampsia (PE/CH-PE), with adjusted ORs of 0.554 (95% CI: 0.354-0.866) and 0.226 (95% CI: 0.080-0.634). Moreover, compared with traditional factors (TFs) model, the TMAO metabolites+ TFs model had a higher predictive ability for PE/CH-PE (all indexes P values < 0.0001). Therefore, it suggests that the detection of plasma betaine and choline in the early second trimester of pregnancy can better assess the risk of HDP.
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Affiliation(s)
- He Xu
- Department of Epidemiology and Biostatistics, School of Public Health, Suzhou Medical College of Soochow University, Suzhou, 215123, China
| | - Pei Feng
- Department of Community Health Care, Kunshan Maternity and Children's Health Care Hospital, Kunshan, China
| | - Yexiu Sun
- Department of Epidemiology and Biostatistics, School of Public Health, Suzhou Medical College of Soochow University, Suzhou, 215123, China
| | - Di Wu
- Department of Epidemiology and Biostatistics, School of Public Health, Suzhou Medical College of Soochow University, Suzhou, 215123, China
| | - Dandan Wang
- Department of Epidemiology and Biostatistics, School of Public Health, Suzhou Medical College of Soochow University, Suzhou, 215123, China
| | - Lei Wu
- Department of Maternal and Child Health, Suzhou Industrial Park Center for Disease Control and Prevention, Suzhou, China
| | - Hao Peng
- Department of Epidemiology and Biostatistics, School of Public Health, Suzhou Medical College of Soochow University, Suzhou, 215123, China.
- MOE Key Laboratory of Geriatric Diseases and Immunology, Suzhou, 215123, China.
| | - Hongmei Li
- Department of Epidemiology and Biostatistics, School of Public Health, Suzhou Medical College of Soochow University, Suzhou, 215123, China.
- MOE Key Laboratory of Geriatric Diseases and Immunology, Suzhou, 215123, China.
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Identification of AGXT2, SHMT1, and ACO2 as important biomarkers of acute kidney injury by WGCNA. PLoS One 2023; 18:e0281439. [PMID: 36735737 PMCID: PMC9897545 DOI: 10.1371/journal.pone.0281439] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Accepted: 01/23/2023] [Indexed: 02/04/2023] Open
Abstract
Acute kidney injury (AKI) is a serious and frequently observed disease associated with high morbidity and mortality. Weighted gene co-expression network analysis (WGCNA) is a research method that converts the relationship between tens of thousands of genes and phenotypes into the association between several gene sets and phenotypes. We screened potential target genes related to AKI through WGCNA to provide a reference for the diagnosis and treatment of AKI. Key biomolecules of AKI were investigated based on transcriptome analysis. RNA sequencing data from 39 kidney biopsy specimens of AKI patients and 9 normal subjects were downloaded from the GEO database. By WGCNA, the top 20% of mRNAs with the largest variance in the data matrix were used to construct a gene co-expression network with a p-value < 0.01 as a screening condition, showing that the blue module was most closely associated with AKI. Thirty-two candidate biomarker genes were screened according to the threshold values of |MM|≥0.86 and |GS|≥0.4, and PPI and enrichment analyses were performed. The top three genes with the most connected nodes, alanine-glyoxylate aminotransferase 2(AGXT2), serine hydroxymethyltransferase 1(SHMT1) and aconitase 2(ACO2), were selected as the central genes based on the PPI network. A rat AKI model was constructed, and the mRNA and protein expression levels of the central genes in the model and control groups were verified by PCR and immunohistochemistry experiments. The results showed that the relative mRNA expression and protein levels of AGXT2, SHMT1 and ACO2 showed a decrease in the model group. In conclusion, we inferred that there is a close association between AGXT2, SHMT1 and ACO2 genes and the development of AKI, and the down-regulation of their expression levels may induce AKI.
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Li J, Li F, Yu N, Liu Z. The betaine-dependent remethylation pathway is a homocysteine metabolism pathway associated with the carnivorous feeding habits of spiders. INSECT SCIENCE 2022; 29:1047-1058. [PMID: 34647692 DOI: 10.1111/1744-7917.12976] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 09/08/2021] [Accepted: 09/21/2021] [Indexed: 06/13/2023]
Abstract
Homocysteine (Hcy) is a sulfur-containing amino acid derived from the essential amino acid methionine (Met). Circulating levels of Hcy in animals can be increased by feeding on Met-enriched diets, which is generally considered harmful. Spiders are one of the largest groups of obligate carnivores and feed on animals high in protein and Met. We analyzed the Hcy metabolism pathways in 18 species of 3 taxa (Mammalia, Insecta, and Arachnida) and found that the betaine-dependent remethylation pathway (BRP) was present in all carnivorous arachnid species and mammals but absent in insects and red spider mites. We then studied the Hcy metabolism pathway in Pardosa pseudoannulata. In P. pseudoannulata, Hcy is metabolized through the transsulfuration pathway, BRP, and S-methylmethionine-dependent remethylation pathway. Because of a prior duplication event of the betaine homocysteine S-methyltransferase (BHMT) gene in the BRP, BHMTa and BHMTb are present in tandem in the genome of P. pseudoannulata. The high expression levels of BHMTa and its high abundance in detoxification tissues indicate that it plays an important role in the BRP; the ability of BHMTa and BHMTb to remethylate Hcy using betaine as substrate was similar. Compared with other Hcy metabolic enzyme genes, BHMT responded quickly to the application of Hcy or betaine. In sum, the BRP is important in Hcy metabolism in P. pseudoannulata and in other spider species.
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Affiliation(s)
- Jingjing Li
- Key laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Fangfang Li
- Key laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Na Yu
- Key laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Zewen Liu
- Key laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), College of Plant Protection, Nanjing Agricultural University, Nanjing, China
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The Role of Betaine in Patients With Chronic Kidney Disease: a Narrative Review. Curr Nutr Rep 2022; 11:395-406. [PMID: 35792998 DOI: 10.1007/s13668-022-00426-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/13/2022] [Indexed: 10/17/2022]
Abstract
PURPOSE OF REVIEW This narrative review aimed to explore the functions of betaine and discuss its role in patients with chronic kidney disease (CKD). RECENT FINDINGS Some studies on CKD animal models have shown the benefits of betaine supplementation, including decreased kidney damage, antioxidant recovery status, and decreased inflammation. Betaine (N-trimethylglycine) is an N-trimethylated amino acid with an essential regulatory osmotic function. Moreover, it is a methyl donor and has anti-inflammatory and antioxidant properties. Additionally, betaine has positive effects on intestinal health by regulating the osmolality and gut microbiota. Due to these crucial functions, betaine has been studied in several diseases, including CKD, in which betaine plasma levels decline with the progression of the disease. Low betaine levels are linked to increased kidney damage, inflammation, oxidative stress, and intestinal dysbiosis. Furthermore, betaine is considered an essential metabolite for identifying CKD stages.
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Monné M, Marobbio CMT, Agrimi G, Palmieri L, Palmieri F. Mitochondrial transport and metabolism of the major methyl donor and versatile cofactor S-adenosylmethionine, and related diseases: A review †. IUBMB Life 2022; 74:573-591. [PMID: 35730628 DOI: 10.1002/iub.2658] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Accepted: 05/19/2022] [Indexed: 11/08/2022]
Abstract
S-adenosyl-L-methionine (SAM) is a coenzyme and the most commonly used methyl-group donor for the modification of metabolites, DNA, RNA and proteins. SAM biosynthesis and SAM regeneration from the methylation reaction product S-adenosyl-L-homocysteine (SAH) take place in the cytoplasm. Therefore, the intramitochondrial SAM-dependent methyltransferases require the import of SAM and export of SAH for recycling. Orthologous mitochondrial transporters belonging to the mitochondrial carrier family have been identified to catalyze this antiport transport step: Sam5p in yeast, SLC25A26 (SAMC) in humans, and SAMC1-2 in plants. In mitochondria SAM is used by a vast number of enzymes implicated in the following processes: the regulation of replication, transcription, translation, and enzymatic activities; the maturation and assembly of mitochondrial tRNAs, ribosomes and protein complexes; and the biosynthesis of cofactors, such as ubiquinone, lipoate, and molybdopterin. Mutations in SLC25A26 and mitochondrial SAM-dependent enzymes have been found to cause human diseases, which emphasizes the physiological importance of these proteins.
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Affiliation(s)
- Magnus Monné
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy.,Department of Sciences, University of Basilicata, Potenza, Italy
| | - Carlo M T Marobbio
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy
| | - Gennaro Agrimi
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy
| | - Luigi Palmieri
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy.,CNR Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies (IBIOM), Bari, Italy
| | - Ferdinando Palmieri
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy.,CNR Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies (IBIOM), Bari, Italy
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Van Every DW, Plotkin DL, Delcastillo K, Cholewa J, Schoenfeld BJ. Betaine Supplementation: A Critical Review of Its Efficacy for Improving Muscle Strength, Power, and Body Composition. Strength Cond J 2021. [DOI: 10.1519/ssc.0000000000000622] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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Tscherner AK, Macaulay AD, Ortman CS, Baltz JM. Initiation of cell volume regulation and unique cell volume regulatory mechanisms in mammalian oocytes and embryos. J Cell Physiol 2021; 236:7117-7133. [PMID: 33634482 DOI: 10.1002/jcp.30352] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 02/09/2021] [Accepted: 02/17/2021] [Indexed: 11/07/2022]
Abstract
The period beginning with the signal for ovulation, when a fully-grown oocyte progresses through meiosis to become a mature egg that is fertilized and develops as a preimplantation embryo, is crucial for healthy development. The early preimplantation embryo is unusually sensitive to cell volume perturbations, with even moderate decreases in volume or dysregulation of volume-regulatory mechanisms resulting in developmental arrest. To prevent this, early embryos possess mechanisms of cell volume control that are apparently unique to them. These rely on the accumulation of glycine and betaine (N, N, N-trimethylglycine) as organic osmolytes-compounds that can provide intracellular osmotic support without the deleterious effects of inorganic ions. Preimplantation embryos also have the same mechanisms as somatic cells that mediate rapid responses to deviations in cell volume, which rely on inorganic ion transport. Both the unique, embryo-specific mechanisms that use glycine and betaine and the inorganic ion-dependent mechanisms undergo major changes during meiotic maturation and preimplantation development. The most profound changes occur immediately after ovulation is triggered. Before this, oocytes cannot regulate their volume, since they are strongly attached to their rigid extracellular matrix shell, the zona pellucida. After ovulation is triggered, the oocyte detaches from the zona pellucida and first becomes capable of independent volume regulation. A complex set of developmental changes in each cell volume-regulatory mechanism continues through egg maturation and preimplantation development. The unique cell volume-regulatory mechanisms in eggs and preimplantation embryos and the developmental changes they undergo appear critical for normal healthy embryo development.
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Affiliation(s)
- Allison K Tscherner
- Ottawa Hospital Research Institute, Ottawa, Ontario, Canada
- Department of Obstetrics and Gynecology, University of Ottawa, Ottawa, Ontario, Canada
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Angus D Macaulay
- Ottawa Hospital Research Institute, Ottawa, Ontario, Canada
- Department of Obstetrics and Gynecology, University of Ottawa, Ottawa, Ontario, Canada
| | - Chyna S Ortman
- Ottawa Hospital Research Institute, Ottawa, Ontario, Canada
- Department of Obstetrics and Gynecology, University of Ottawa, Ottawa, Ontario, Canada
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Jay M Baltz
- Ottawa Hospital Research Institute, Ottawa, Ontario, Canada
- Department of Obstetrics and Gynecology, University of Ottawa, Ottawa, Ontario, Canada
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada
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8
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Stipanuk MH. Metabolism of Sulfur-Containing Amino Acids: How the Body Copes with Excess Methionine, Cysteine, and Sulfide. J Nutr 2020; 150:2494S-2505S. [PMID: 33000151 DOI: 10.1093/jn/nxaa094] [Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 02/28/2020] [Accepted: 03/16/2020] [Indexed: 02/06/2023] Open
Abstract
Metabolism of excess methionine (Met) to homocysteine (Hcy) by transmethylation is facilitated by the expression of methionine adenosyltransferase (MAT) I/III and glycine N-methyltransferase (GNMT) in liver, and a lack of either enzyme results in hypermethioninemia despite normal concentrations of MATII and methyltransferases other than GNMT. The further metabolism of Hcy by the transsulfuration pathway is facilitated by activation of cystathionine β-synthase (CBS) by S-adenosylmethionine (SAM) as well as the relatively high KM of CBS for Hcy. Transmethylation plus transsulfuration effects catabolism of the Met molecule along with transfer of the sulfur atom of Met to serine to synthesize cysteine (Cys). Oxidation and excretion of Met sulfur depend upon Cys catabolism and sulfur oxidation pathways. Excess Cys is oxidized by cysteine dioxygenase 1 (CDO1) and further metabolized to taurine or sulfate. Some Cys is normally metabolized by desulfhydration pathways, and the hydrogen sulfide (H2S) produced is further oxidized to sulfate. If Cys or Hcy concentrations are elevated, Cys or Hcy desulfhydration can result in excess H2S and thiosulfate production. Excess Cys or Met may also promote their limited metabolism by transamination pathways.
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Affiliation(s)
- Martha H Stipanuk
- Division of Nutritional Sciences, Cornell University, Ithaca, NY, USA
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Jozi M, Jafarpour F, Moradi R, Zadegan FG, Karbalaie K, Nasr-Esfahani MH. Induced DNA hypomethylation by Folic Acid Deprivation in Bovine Fibroblast Donor Cells Improves Reprogramming of Somatic Cell Nuclear Transfer Embryos. Sci Rep 2020; 10:5076. [PMID: 32193457 PMCID: PMC7081283 DOI: 10.1038/s41598-020-61797-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Accepted: 03/02/2020] [Indexed: 12/20/2022] Open
Abstract
Aberrant patterns of DNA methylation are consistent events in SCNT derived embryos and mechanistically are believed to be related to abnormal development. While some epigenetic drugs have been used in attempts to improve SCNT efficiency but some concerns remained toward the safety of these drugs on the health of future offspring. Folate is an essential cofactor in one‐carbon cycle for conversion of homocysteine to methionine, thereby ensuring supply of SAM, the universal methyl donor for many biological methylation reactions including DNA methylation. Therefore, in vitro DNA hypo-methylation can be induced by folate deprivation and this study aims at deciphering the role of folic acid deprivation in culture medium of BFFs for 6 days on SCNT efficiency. Our data revealed that culture of fibroblast cells in folate− medium containing 0.5% FBS did not alter the cell cycle compared to other groups. Flowcytometric analysis revealed that DNA methylation (5-mC level) in folate deprived cells cultured in 0.5% serum was decreased compared to folate+ group. The result of bisulfite sequencing was in accordance with flowcytometric analysis, which indicated a decrease in DNA methylation of POU5F1 promoter. Gene expression analysis revealed an increase in expression of POU5F1 gene in folate− group. The nuclear area of the cells in folate− group was significantly larger than folate+ group. Induced DNA hypomethylation by folate deprivation in the folate− group significantly improved blastocyst rate compared to the folate+ group. DNA methylation level in POU5F1 promoter and ICR of H19 and IGF2 of SCNT derived embryos in the folate− group was similar to the IVF derived blastocysts. In conclusion, our results proposes a promising “non-chemical” instead of “chemical” approach using inhibitors of epigenetic modifier enzymes for improving mammalian SCNT efficiency for agricultural and biomedical purposes.
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Affiliation(s)
- Mina Jozi
- Department of Reproductive Biotechnology, Reproductive Biomedicine Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran.,ACECR Institute of Higher Education (Isfahan Branch), Isfahan, Iran
| | - Farnoosh Jafarpour
- Department of Reproductive Biotechnology, Reproductive Biomedicine Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran.
| | - Reza Moradi
- Department of Reproductive Biotechnology, Reproductive Biomedicine Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran
| | - Faezeh Ghazvini Zadegan
- Department of Reproductive Biotechnology, Reproductive Biomedicine Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran
| | - Khadijeh Karbalaie
- Department of Cellular Biotechnology at Cell Science Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran
| | - Mohammad Hossein Nasr-Esfahani
- Department of Reproductive Biotechnology, Reproductive Biomedicine Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran.
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Abstract
Homocysteine (Hcy) is a thiol group containing the amino acid, which naturally occurs in all humans. Hcy is degraded in the body through two metabolic pathways, while a minor part is excreted through kidneys. The chemical reactions that are necessary for degradation of Hcy require the presence of folic acid, vitamins B6 and B12. Consequently, the level of the total Hcy in the serum is influenced by the presence or absence of these vitamins. An elevated level of the Hcy, hyperhomocysteinemia (HHcy) and homocystinuria is connected with occlusive artery disease, especially in the brain, the heart, and the kidney, in addition to venous thrombosis, chronic renal failure, megaloblastic anemia, osteoporosis, depression, Alzheimer's disease, pregnancy problems, and others. Elevated Hcy levels are connected with various pathologies both in adult and child population. Causes of HHcy include genetic mutations and enzyme deficiencies in 5, 10-methylenetetrahydrofolate reductase (MTHFR) methionine synthase (MS), and cystathionine β-synthase (CβS). HHcy can be caused by deficiencies in the folate, vitamin B12 and to a lesser extent, deficiency in B6 vitamin what influences methionine metabolism. Additionally, HHcy can be caused by the rich diet and renal impairment. This review presents literature data from recent research related to Hcy metabolism and the etiology of the Hcy blood level disorder. In addition, we also described various pathological mechanisms induced by hereditary disturbances or nutritional influences and their association with HHcy induced pathology in adults and children and treatment of these metabolic disorders.
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Affiliation(s)
- Bozidarka L Zaric
- Institute of nuclear science Vinca, University of Belgrade, Laboratory of Radiobiology and Molecular Genetics, Belgrade, Serbia
| | - Milan Obradovic
- Institute of nuclear science Vinca, University of Belgrade, Laboratory of Radiobiology and Molecular Genetics, Belgrade, Serbia
| | - Vladan Bajic
- Institute of nuclear science Vinca, University of Belgrade, Laboratory of Radiobiology and Molecular Genetics, Belgrade, Serbia
| | - Mohamed A Haidara
- Department of Physiology, College of Medicine, King Khalid University, Abha, Saudi Arabia
| | - Milos Jovanovic
- Faculty of Biology, University of Belgrade, Institute of physiology and biochemistry, Belgrade, Serbia
| | - Esma R Isenovic
- Institute of nuclear science Vinca, University of Belgrade, Laboratory of Radiobiology and Molecular Genetics, Belgrade, Serbia
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Chen YF, Lin IH, Guo YR, Chiu WJ, Wu MS, Jia W, Yen Y. Rrm2b deletion causes mitochondrial metabolic defects in renal tubules. Sci Rep 2019; 9:13238. [PMID: 31519977 PMCID: PMC6744457 DOI: 10.1038/s41598-019-49663-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Accepted: 06/18/2019] [Indexed: 12/22/2022] Open
Abstract
Renal diseases impose considerable health and economic burdens on health systems worldwide, and there is a lack of efficient methods for the prevention and treatment due to their complexity and heterogeneity. Kidneys are organs with a high demand for energy produced by mitochondria, in which Rrm2b has critical functions as reported. The Rrm2b kidney-specific knockout mice we generated exhibited age-dependent exacerbated features, including mitochondrial dysfunction and increased oxidative stress; additionally, resulted in severe disruption of mitochondria-related metabolism. Rrm2b is vital not only to supply dNTPs for DNA replication and repair, but also to maintain structural integrity and metabolic homeostasis in mitochondria. Thence, Rrm2b deletion might induce chronic kidney defects in mice. This model can facilitate exploration of novel mechanisms and targeted therapies in the kidney diseases and has important translational and clinical implications.
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Affiliation(s)
- Yi-Fan Chen
- The Ph.D. Program for Translational Medicine, College of Medical Science and Technology, Taipei Medical University, 11031, Taipei, Taiwan
| | - I-Hsuan Lin
- TMU Research Center of Cancer Translational Medicine, Taipei Medical University, 11031, Taipei, Taiwan
| | - Yu-Ru Guo
- Ph.D. Program of Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, 11031, Taipei, Taiwan
| | - Wei-Jun Chiu
- The Ph.D. Program for Translational Medicine, College of Medical Science and Technology, Taipei Medical University, 11031, Taipei, Taiwan
| | - Mai-Szu Wu
- Department of Internal Medicine, School of Medicine, College of Medicine, Taipei Medical University, 11031, Taipei, Taiwan.,Division of Nephrology, Department of Internal Medicine, Taipei Medical University-Shuang Ho Hospital, 23561, New Taipei City, Taiwan
| | - Wei Jia
- Cancer Biology Program, University of Hawaii Cancer Center, Honolulu, HI, 96813, USA
| | - Yun Yen
- TMU Research Center of Cancer Translational Medicine, Taipei Medical University, 11031, Taipei, Taiwan. .,Ph.D. Program of Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, 11031, Taipei, Taiwan.
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12
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Froese DS, Fowler B, Baumgartner MR. Vitamin B 12 , folate, and the methionine remethylation cycle-biochemistry, pathways, and regulation. J Inherit Metab Dis 2019; 42:673-685. [PMID: 30693532 DOI: 10.1002/jimd.12009] [Citation(s) in RCA: 192] [Impact Index Per Article: 38.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Revised: 09/27/2018] [Accepted: 10/19/2018] [Indexed: 12/16/2022]
Abstract
Vitamin B12 (cobalamin, Cbl) is a nutrient essential to human health. Due to its complex structure and dual cofactor forms, Cbl undergoes a complicated series of absorptive and processing steps before serving as cofactor for the enzymes methylmalonyl-CoA mutase and methionine synthase. Methylmalonyl-CoA mutase is required for the catabolism of certain (branched-chain) amino acids into an anaplerotic substrate in the mitochondrion, and dysfunction of the enzyme itself or in production of its cofactor adenosyl-Cbl result in an inability to successfully undergo protein catabolism with concomitant mitochondrial energy disruption. Methionine synthase catalyzes the methyl-Cbl dependent (re)methylation of homocysteine to methionine within the methionine cycle; a reaction required to produce this essential amino acid and generate S-adenosylmethionine, the most important cellular methyl-donor. Disruption of methionine synthase has wide-ranging implications for all methylation-dependent reactions, including epigenetic modification, but also for the intracellular folate pathway, since methionine synthase uses 5-methyltetrahydrofolate as a one-carbon donor. Folate-bound one-carbon units are also required for deoxythymidine monophosphate and de novo purine synthesis; therefore, the flow of single carbon units to each of these pathways must be regulated based on cellular needs. This review provides an overview on Cbl metabolism with a brief description of absorption and intracellular metabolic pathways. It also provides a description of folate-mediated one-carbon metabolism and its intersection with Cbl at the methionine cycle. Finally, a summary of recent advances in understanding of how both pathways are regulated is presented.
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Affiliation(s)
- D Sean Froese
- Division of Metabolism and Children's Research Center, University Children's Hospital, Zurich, Switzerland
| | - Brian Fowler
- Division of Metabolism and Children's Research Center, University Children's Hospital, Zurich, Switzerland
| | - Matthias R Baumgartner
- Division of Metabolism and Children's Research Center, University Children's Hospital, Zurich, Switzerland
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13
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Dietary Choline Intake: Current State of Knowledge Across the Life Cycle. Nutrients 2018; 10:nu10101513. [PMID: 30332744 PMCID: PMC6213596 DOI: 10.3390/nu10101513] [Citation(s) in RCA: 173] [Impact Index Per Article: 28.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Revised: 10/10/2018] [Accepted: 10/13/2018] [Indexed: 12/13/2022] Open
Abstract
Choline, an essential dietary nutrient for humans, is required for the synthesis of the neurotransmitter, acetylcholine, the methyl group donor, betaine, and phospholipids; and therefore, choline is involved in a broad range of critical physiological functions across all stages of the life cycle. The current dietary recommendations for choline have been established as Adequate Intakes (AIs) for total choline; however, dietary choline is present in multiple different forms that are both water-soluble (e.g., free choline, phosphocholine, and glycerophosphocholine) and lipid-soluble (e.g., phosphatidylcholine and sphingomyelin). Interestingly, the different dietary choline forms consumed during infancy differ from those in adulthood. This can be explained by the primary food source, where the majority of choline present in human milk is in the water-soluble form, versus lipid-soluble forms for foods consumed later on. This review summarizes the current knowledge on dietary recommendations and assessment methods, and dietary choline intake from food sources across the life cycle.
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Moore JR, Hubler SL, Nelson CD, Nashold FE, Spanier JA, Hayes CE. 1,25-Dihydroxyvitamin D 3 increases the methionine cycle, CD4 + T cell DNA methylation and Helios +Foxp3 + T regulatory cells to reverse autoimmune neurodegenerative disease. J Neuroimmunol 2018; 324:100-114. [PMID: 30267995 DOI: 10.1016/j.jneuroim.2018.09.008] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2018] [Revised: 09/12/2018] [Accepted: 09/18/2018] [Indexed: 12/21/2022]
Abstract
We investigated how one calcitriol dose plus vitamin D3 reverses experimental autoimmune encephalomyelitis (EAE), a multiple sclerosis model. This protocol rapidly increased CD4+ T cell Ikzf2 transcripts, Helios protein, and CD4+Helios+FoxP3+ T regulatory cells. It also rapidly increased CD4+ T cell Bhmt1 transcripts, betaine:homocysteine methyltransferase-1 (BHMT1) enzyme activity, and global DNA methylation. BHMT1 transmethylates homocysteine to replenish methionine. Targeting the Vdr gene in T cells decreased Ikzf2 and Bhmt1 gene expression, reduced DNA methylation, and elevated systemic homocysteine in mice with EAE. We hypothesize that calcitriol drives a transition from encephalitogenic CD4+ T cell to Treg cell dominance by upregulating Ikzf2 and Bhmt1, recycling homocysteine to methionine, reducing homocysteine toxicity, maintaining DNA methylation, and stabilizing CD4+Helios+FoxP3+Tregulatory cells. Conserved vitamin D-responsive element (VDRE)-type sequences in the Bhmt1 and Ikzf2 promoters, the universal need for methionine in epigenetic regulation, and betaine's protective effects in MTHFR-deficiency suggest similar regulatory mechanisms exist in humans.
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Affiliation(s)
- Jerott R Moore
- Department of Biochemistry, College of Agricultural and Life Sciences, University of Wisconsin-Madison, 433 Babcock Drive, Madison, WI 53706, United States
| | | | - Corwin D Nelson
- Department of Animal Sciences, University of Florida, Gainesville, FL 32611, United States
| | - Faye E Nashold
- Department of Biochemistry, College of Agricultural and Life Sciences, University of Wisconsin-Madison, 433 Babcock Drive, Madison, WI 53706, United States
| | - Justin A Spanier
- Rheumatic and Autoimmune Diseases, Center for Immunology, Department of Medicine, University of Minnesota, Minneapolis, MN 55455, United States.
| | - Colleen E Hayes
- Department of Biochemistry, College of Agricultural and Life Sciences, University of Wisconsin-Madison, 433 Babcock Drive, Madison, WI 53706, United States.
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15
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Garrido F, Pacheco M, Vargas-Martínez R, Velasco-García R, Jorge I, Serrano H, Portillo F, Vázquez J, Pajares MÁ. Identification of hepatic protein-protein interaction targets for betaine homocysteine S-methyltransferase. PLoS One 2018; 13:e0199472. [PMID: 29924862 PMCID: PMC6010280 DOI: 10.1371/journal.pone.0199472] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Accepted: 06/07/2018] [Indexed: 01/01/2023] Open
Abstract
Protein-protein interactions are an important mechanism for the regulation of enzyme function allowing metabolite channeling, crosstalk between pathways or the introduction of post-translational modifications. Therefore, a number of high-throughput studies have been carried out to shed light on the protein networks established under different pathophysiological settings. Surprisingly, this type of information is quite limited for enzymes of intermediary metabolism such as betaine homocysteine S-methyltransferase, despite its high hepatic abundancy and its role in homocysteine metabolism. Here, we have taken advantage of two approaches, affinity purification combined with mass spectrometry and yeast two-hybrid, to further uncover the array of interactions of betaine homocysteine S-methyltransferase in normal liver of Rattus norvegicus. A total of 131 non-redundant putative interaction targets were identified, out of which 20 were selected for further validation by coimmunoprecipitation. Interaction targets validated by two different methods include: S-methylmethionine homocysteine methyltransferase or betaine homocysteine methyltransferase 2, methionine adenosyltransferases α1 and α2, cAMP-dependent protein kinase catalytic subunit alpha, 4-hydroxyphenylpyruvic acid dioxygenase and aldolase b. Network analysis identified 122 nodes and 165 edges, as well as a limited number of KEGG pathways that comprise: the biosynthesis of amino acids, cysteine and methionine metabolism, the spliceosome and metabolic pathways. These results further expand the connections within the hepatic methionine cycle and suggest putative cross-talks with additional metabolic pathways that deserve additional research.
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Affiliation(s)
- Francisco Garrido
- Instituto de Investigaciones Biomédicas Alberto Sols (CSIC-UAM), Arturo Duperier 4, Madrid, Spain
| | - María Pacheco
- Instituto de Investigaciones Biomédicas Alberto Sols (CSIC-UAM), Arturo Duperier 4, Madrid, Spain
| | - Rocío Vargas-Martínez
- Instituto de Investigaciones Biomédicas Alberto Sols (CSIC-UAM), Arturo Duperier 4, Madrid, Spain
| | - Roberto Velasco-García
- Instituto de Investigaciones Biomédicas Alberto Sols (CSIC-UAM), Arturo Duperier 4, Madrid, Spain
| | - Inmaculada Jorge
- Cardiovascular Proteomics Group, Spanish National Center for Cardiovascular Research (CNIC) and CIBERCV, Melchor Fernández de Almagro 3, Madrid, Spain
| | - Horacio Serrano
- Department of Internal Medicine, University of Puerto Rico, Medical Sciences Campus, San Juan, Puerto Rico
| | - Francisco Portillo
- Instituto de Investigaciones Biomédicas Alberto Sols (CSIC-UAM), Arturo Duperier 4, Madrid, Spain
- Instituto de Investigación Sanitaria La Paz (IdiPAZ), Paseo de la Castellana 261, Madrid, Spain
- Departamento de Bioquímica, Facultad de Medicina, Universidad Autónoma de Madrid, Arzobispo Morcillo 4, Madrid, Spain
- Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), Instituto de Salud Carlos III, Madrid, Spain
| | - Jesús Vázquez
- Cardiovascular Proteomics Group, Spanish National Center for Cardiovascular Research (CNIC) and CIBERCV, Melchor Fernández de Almagro 3, Madrid, Spain
| | - María Ángeles Pajares
- Instituto de Investigaciones Biomédicas Alberto Sols (CSIC-UAM), Arturo Duperier 4, Madrid, Spain
- Instituto de Investigación Sanitaria La Paz (IdiPAZ), Paseo de la Castellana 261, Madrid, Spain
- Departamento de Biología Estructural y Química, Centro de Investigaciones Biológicas (CSIC), Ramiro de Maeztu 9, Madrid, Spain
- * E-mail:
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16
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Prieur EAK, Pjetri E, Zeisel SH, Jadavji NM. Reduced brain volume and impaired memory in betaine homocysteine S-methyltransferase knockout mice. Appl Physiol Nutr Metab 2017; 42:1228-1231. [PMID: 28715642 DOI: 10.1139/apnm-2017-0182] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Using a mouse model, this study examined the impact of lack of betaine homocysteine S-methyltransferase (BHMT) on neurological function. Bhmt-/- mice maintained on a control diet had elevated concentrations of homocysteine, reduced total brain magnetic resonance imaging (MRI) volume, as well as impaired reference and short-term memories. The results of this study indicate that the absence of BHMT may play a role in neurological function.
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Affiliation(s)
- Emily A K Prieur
- a Department of Neuroscience, Carleton University, 1125 Colonel By Drive, Ottawa, ON K1S 5B6, Canada
| | - Eneda Pjetri
- b Department of Nutrition, UNC Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC 27599-7461, USA.,c UNC School of Medicine, University of North Carolina, Chapel Hill, NC 27516, USA.,d Nutrition Research Institute, University of North Carolina at Chapel Hill, Chapel Hill, NC 28081, USA
| | - Steven H Zeisel
- b Department of Nutrition, UNC Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC 27599-7461, USA.,c UNC School of Medicine, University of North Carolina, Chapel Hill, NC 27516, USA.,d Nutrition Research Institute, University of North Carolina at Chapel Hill, Chapel Hill, NC 28081, USA
| | - Nafisa M Jadavji
- a Department of Neuroscience, Carleton University, 1125 Colonel By Drive, Ottawa, ON K1S 5B6, Canada.,e Department of Experimental Neurology, Center for Stroke Research Berlin, Charité University Medicine Berlin, Berlin 10117, Germany
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17
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McClatchie T, Meredith M, Ouédraogo MO, Slow S, Lever M, Mann MRW, Zeisel SH, Trasler JM, Baltz JM. Betaine is accumulated via transient choline dehydrogenase activation during mouse oocyte meiotic maturation. J Biol Chem 2017; 292:13784-13794. [PMID: 28663368 DOI: 10.1074/jbc.m117.803080] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Indexed: 11/06/2022] Open
Abstract
Betaine (N,N,N-trimethylglycine) plays key roles in mouse eggs and preimplantation embryos first in a novel mechanism of cell volume regulation and second as a major methyl donor in blastocysts, but its origin is unknown. Here, we determined that endogenous betaine was present at low levels in germinal vesicle (GV) stage mouse oocytes before ovulation and reached high levels in the mature, ovulated egg. However, no betaine transport into oocytes was detected during meiotic maturation. Because betaine can be synthesized in mammalian cells via choline dehydrogenase (CHDH; EC 1.1.99.1), we assessed whether this enzyme was expressed and active. Chdh transcripts and CHDH protein were expressed in oocytes. No CHDH enzyme activity was detected in GV oocyte lysate, but CHDH became highly active during oocyte meiotic maturation. It was again inactive after fertilization. We then determined whether oocytes synthesized betaine and whether CHDH was required. Isolated maturing oocytes autonomously synthesized betaine in vitro in the presence of choline, whereas this failed to occur in Chdh-/- oocytes, directly demonstrating a requirement for CHDH for betaine accumulation in oocytes. Overall, betaine accumulation is a previously unsuspected physiological process during mouse oocyte meiotic maturation whose underlying mechanism is the transient activation of CHDH.
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Affiliation(s)
- Taylor McClatchie
- From the Ottawa Hospital Research Institute, Ottawa, Ontario K1H 8L6, Canada.,the Departments of Obstetrics and Gynecology and Cellular and Molecular Medicine, University of Ottawa Faculty of Medicine, Ottawa, Ontario K1H 8M5, Canada
| | - Megan Meredith
- From the Ottawa Hospital Research Institute, Ottawa, Ontario K1H 8L6, Canada.,the Departments of Obstetrics and Gynecology and Cellular and Molecular Medicine, University of Ottawa Faculty of Medicine, Ottawa, Ontario K1H 8M5, Canada
| | - Mariame O Ouédraogo
- From the Ottawa Hospital Research Institute, Ottawa, Ontario K1H 8L6, Canada.,the Departments of Obstetrics and Gynecology and Cellular and Molecular Medicine, University of Ottawa Faculty of Medicine, Ottawa, Ontario K1H 8M5, Canada
| | - Sandy Slow
- the Department of Pathology, University of Otago, Christchurch 8140, New Zealand
| | - Michael Lever
- the Department of Chemistry, University of Canterbury, Christchurch 8041, New Zealand
| | - Mellissa R W Mann
- the Department of Obstetrics, Gynecology, and Reproductive Sciences, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15213.,the Magee-Womens Research Institute, Pittsburgh, Pennsylvania 15213
| | - Steven H Zeisel
- the Department of Nutrition, Nutrition Research Institute, Gillings School of Global Public Health and School of Medicine, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Jacquetta M Trasler
- the Montréal Children's Hospital and Research Institute of the McGill University Health Centre, Montréal, Quebec H4A 3J1, Canada, and.,the Departments of Human Genetics, Pediatrics, and Pharmacology and Therapeutics, McGill University, Montréal, Quebec H3A 1B1, Canada
| | - Jay M Baltz
- From the Ottawa Hospital Research Institute, Ottawa, Ontario K1H 8L6, Canada, .,the Departments of Obstetrics and Gynecology and Cellular and Molecular Medicine, University of Ottawa Faculty of Medicine, Ottawa, Ontario K1H 8M5, Canada
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18
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Pérez-Miguelsanz J, Vallecillo N, Garrido F, Reytor E, Pérez-Sala D, Pajares MA. Betaine homocysteine S-methyltransferase emerges as a new player of the nuclear methionine cycle. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2017; 1864:1165-1182. [PMID: 28288879 DOI: 10.1016/j.bbamcr.2017.03.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 03/08/2017] [Accepted: 03/09/2017] [Indexed: 12/29/2022]
Abstract
The paradigm of a cytoplasmic methionine cycle synthesizing/eliminating metabolites that are transported into/out of the nucleus as required has been challenged by detection of significant nuclear levels of several enzymes of this pathway. Here, we show betaine homocysteine S-methyltransferase (BHMT), an enzyme that exerts a dual function in maintenance of methionine levels and osmoregulation, as a new component of the nuclear branch of the cycle. In most tissues, low expression of Bhmt coincides with a preferential nuclear localization of the protein. Conversely, the liver, with very high Bhmt expression levels, presents a main cytoplasmic localization. Nuclear BHMT is an active homotetramer in normal liver, although the total enzyme activity in this fraction is markedly lower than in the cytosol. N-terminal basic residues play a role in cytoplasmic retention and the ratio of glutathione species regulates nucleocytoplasmic distribution. The oxidative stress associated with d-galactosamine (Gal) or buthionine sulfoximine (BSO) treatments induces BHMT nuclear translocation, an effect that is prevented by administration of N-acetylcysteine (NAC) and glutathione ethyl ester (EGSH), respectively. Unexpectedly, the hepatic nuclear accumulation induced by Gal associates with reduced nuclear BHMT activity and a trend towards increased protein homocysteinylation. Overall, our results support the involvement of BHMT in nuclear homocysteine remethylation, although moonlighting roles unrelated to its enzymatic activity in this compartment cannot be excluded.
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Affiliation(s)
- Juliana Pérez-Miguelsanz
- Instituto de Investigaciones Biomédicas Alberto Sols (CSIC-UAM), Arturo Duperier 4, 28029 Madrid, Spain; Departamento de Anatomía y Embriología Humanas, Facultad de Medicina, Universidad Complutense de Madrid, Plaza de Ramón y Cajal s/n, 28040 Madrid, Spain
| | - Néstor Vallecillo
- Instituto de Investigaciones Biomédicas Alberto Sols (CSIC-UAM), Arturo Duperier 4, 28029 Madrid, Spain
| | - Francisco Garrido
- Instituto de Investigaciones Biomédicas Alberto Sols (CSIC-UAM), Arturo Duperier 4, 28029 Madrid, Spain
| | - Edel Reytor
- Instituto de Investigaciones Biomédicas Alberto Sols (CSIC-UAM), Arturo Duperier 4, 28029 Madrid, Spain
| | - Dolores Pérez-Sala
- Centro de Investigaciones Biológicas (CSIC), Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - María A Pajares
- Instituto de Investigaciones Biomédicas Alberto Sols (CSIC-UAM), Arturo Duperier 4, 28029 Madrid, Spain; Instituto de Investigación Sanitaria La Paz (IdiPAZ), Paseo de la Castellana 261, 28046 Madrid, Spain.
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19
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Differential proteomic and tissue expression analyses identify valuable diagnostic biomarkers of hepatocellular differentiation and hepatoid adenocarcinomas. Pathology 2016; 47:543-50. [PMID: 26308133 DOI: 10.1097/pat.0000000000000298] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The exact discrimination of lesions with true hepatocellular differentiation from secondary tumours and neoplasms with hepatocellular histomorphology like hepatoid adenocarcinomas (HAC) is crucial. Therefore, we aimed to identify ancillary protein biomarkers by using complementary proteomic techniques (2D-DIGE, label-free MS). The identified candidates were immunohistochemically validated in 14 paired samples of hepatocellular carcinoma (HCC) and non-tumourous liver tissue (NT). The candidates and HepPar1/Arginase1 were afterwards tested for consistency in a large cohort of hepatocellular lesions and NT (n = 290), non-hepatocellular malignancies (n = 383) and HAC (n = 13). Eight non-redundant, differentially expressed proteins were suitable for further immunohistochemical validation and four (ABAT, BHMT, FABP1, HAOX1) for further evaluation. Sensitivity and specificity rates for HCC/HAC were as follows: HepPar1 80.2%, 94.3% / 80.2%, 46.2%; Arginase1 82%, 99.4% / 82%, 69.2%; BHMT 61.4%, 93.8% / 61.4%, 100%; ABAT 84.4%, 33.7% / 84.4%, 30.8%; FABP1 87.2%, 95% / 87.2%, 69.2%; HAOX1 95.5%, 36.3% / 95.5%, 46.2%. The best 2×/3× biomarker panels for the diagnosis of HCC consisted of Arginase1/HAOX1 and BHMT/Arginase1/HAOX1 and for HAC consisted of Arginase1/FABP1 and BHMT/Arginase1/FABP1. In summary, we successfully identified, validated and benchmarked protein biomarker candidates of hepatocellular differentiation. BHMT in particular exhibited superior diagnostic characteristics in hepatocellular lesions and specifically in HAC. BHMT is therefore a promising (panel based) biomarker candidate in the differential diagnostic process of lesions with hepatocellular aspect.
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20
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Downregulation of betaine homocysteine methyltransferase (BHMT) in hepatocellular carcinoma associates with poor prognosis. Tumour Biol 2015; 37:5911-7. [PMID: 26592251 DOI: 10.1007/s13277-015-4443-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2015] [Accepted: 11/13/2015] [Indexed: 12/13/2022] Open
Abstract
Betaine homocysteine methyltransferase (BHMT) catalyzes the synthesis of methionine using betaine and homocysteine (Hcy), which is restricted to the liver and kidney. Impaired BHMT pathway has been associated with hepatocellular carcinogenesis in Bhmt-/- mice model, and decreased BHMT was observed in a small sample of human hepatocellular carcinoma (HCC) patients. However, the prognostic significance of BHMT in HCC has not been elucidated. This study aimed to examine the expression of BHMT in HCC and investigate the relationship between its expression and prognosis of HCC patients. BHMT expression was analyzed in 68 paired HCC samples (HCC tissues vs matched adjacent non-cancerous liver tissues), 115 paraffin-embedded HCC sections (primary cohort), and 65 paraffin-embedded HCC sections (validation cohort) using immunohistochemistry (IHC). The results of IHC analysis showed that BHMT was decreased in tumorous tissues in 85.2 % (58/68) of cases compared to the corresponding adjacent non-tumorous liver tissues. Further correlation analyses indicated that the decreased BHMT expression was closely correlated with serum α-fetoprotein (AFP) (p = 0.011), tumor size (p = 0.039), and vascular invasion (p = 0.017). Moreover, HCC patients with low BHMT expression had shorter overall survival (OS) and time to recurrence (TTR) than those with high BHMT expression in both primary cohort (p < 0.0001) and validation cohort (p < 0.05) assessed by the Kaplan-Meier method. In addition, multivariate analysis showed that BHMT was an independent prognostic factor for OS and TTR in the two cohorts (all p < 0.005). Collectively, our study demonstrated that BHMT could be served as a potential prognostic marker for HCC patients.
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21
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Ganu RS, Ishida Y, Koutmos M, Kolokotronis SO, Roca AL, Garrow TA, Schook LB. Evolutionary Analyses and Natural Selection of Betaine-Homocysteine S-Methyltransferase (BHMT) and BHMT2 Genes. PLoS One 2015. [PMID: 26213999 PMCID: PMC4516251 DOI: 10.1371/journal.pone.0134084] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Betaine-homocysteine S-methyltransferase (BHMT) and BHMT2 convert homocysteine to methionine using betaine and S-methylmethionine, respectively, as methyl donor substrates. Increased levels of homocysteine in blood are associated with cardiovascular disease. Given their role in human health and nutrition, we identified BHMT and BHMT2 genes and proteins from 38 species of deuterostomes including human and non-human primates. We aligned the genes to look for signatures of selection, to infer evolutionary rates and events across lineages, and to identify the evolutionary timing of a gene duplication event that gave rise to two genes, BHMT and BHMT2. We found that BHMT was present in the genomes of the sea urchin, amphibians, reptiles, birds and mammals; BHMT2 was present only across mammals. BHMT and BHMT2 were present in tandem in the genomes of all monotreme, marsupial and placental species examined. Evolutionary rates were accelerated for BHMT2 relative to BHMT. Selective pressure varied across lineages, with the highest dN/dS ratios for BHMT and BHMT2 occurring immediately following the gene duplication event, as determined using GA Branch analysis. Nine codons were found to display signatures suggestive of positive selection; these contribute to the enzymatic or oligomerization domains, suggesting involvement in enzyme function. Gene duplication likely occurred after the divergence of mammals from other vertebrates but prior to the divergence of extant mammalian subclasses, followed by two deletions in BHMT2 that affect oligomerization and methyl donor specificity. The faster evolutionary rate of BHMT2 overall suggests that selective constraints were reduced relative to BHMT. The dN/dS ratios in both BHMT and BHMT2 was highest following the gene duplication, suggesting that purifying selection played a lesser role as the two paralogs diverged in function.
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Affiliation(s)
- Radhika S. Ganu
- Division of Nutritional Sciences, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States of America
| | - Yasuko Ishida
- Department of Animal Sciences, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States of America
| | - Markos Koutmos
- Department of Biochemistry and Molecular Biology, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, United States of America
| | | | - Alfred L. Roca
- Department of Animal Sciences, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States of America
| | - Timothy A. Garrow
- Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States of America
| | - Lawrence B. Schook
- Division of Nutritional Sciences, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States of America
- Department of Animal Sciences, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States of America
- * E-mail:
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22
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Outcomes of four patients with homocysteine remethylation disorders detected by newborn screening. Genet Med 2015; 18:162-7. [PMID: 25856670 DOI: 10.1038/gim.2015.45] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Accepted: 02/23/2015] [Indexed: 01/21/2023] Open
Abstract
PURPOSE We evaluated the clinical outcome in homocysteine remethylation disorders following newborn screening (NBS) and initiation of early specific treatment. METHODS Five patients with remethylation disorders were included in this study. RESULTS Two asymptomatic patients (one with cblG and one with cblE) were identified by NBS using an approach that combines a postanalytical interpretive tool (available on the Region 4 Stork (R4S) collaborative project website, http://www.clir-r4s.org) and a second-tier test for total homocysteine determination. Both the initial screening and the second-tier test are performed on the same blood spot, with no additional patient contact, resulting in no false-positive outcomes. Two additional patients with methylenetetrahydrofolate reductase deficiency were detected by NBS using low methionine as a marker. Although already symptomatic despite the early diagnosis, the latter two patients greatly improved with treatment and their outcomes are compared with that of another patient with methylenetetrahydrofolate reductase deficiency and significant morbidity who was diagnosed clinically at 3 months of age. CONCLUSION Early detection by NBS and timely and specific treatment considerably improve at least short-term outcomes of homocysteine remethylation disorders. When a remethylation disorder is suspected, group-specific treatment could be started prior to the completion of in vitro confirmatory testing because all disorders from this group require similar intervention.
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23
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Ong JLY, Woo JM, Hiong KC, Ching B, Wong WP, Chew SF, Ip YK. Molecular characterization of betaine-homocysteine methyltransferase 1 from the liver, and effects of aestivation on its expressions and homocysteine concentrations in the liver, kidney and muscle, of the African lungfish, Protopterus annectens. Comp Biochem Physiol B Biochem Mol Biol 2015; 183:30-41. [PMID: 25575738 DOI: 10.1016/j.cbpb.2014.12.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2014] [Revised: 12/19/2014] [Accepted: 12/23/2014] [Indexed: 01/12/2023]
Abstract
Homocysteine accumulation has numerous deleterious effects, and betaine-homocysteine S-methyltransferase (BHMT) catalyses the synthesis of methionine from homocysteine and betaine. This study aimed to determine homocysteine concentrations, and mRNA expression levels and protein abundances of bhmt1/Bhmt1 in the liver, kidney and muscle of the African lungfish, Protopterus annectens, during the induction (6 days), maintenance (6 months) or arousal (3 days after arousal) phase of aestivation. The homocysteine concentration decreased significantly in the liver of P. annectens after 6 days or 6 months of aestivation, but it returned to the control level upon arousal. By contrast, homocysteine concentrations in the kidney and muscle remained unchanged during the three phases of aestivation. The complete coding cDNA sequence of bhmt1 from P. annectens consisted of 1236 bp, coding for 412 amino acids. The Bhmt1 from P. annectens had a close phylogenetic relationship with those from tetrapods and Callorhinchus milii. The expression of bhmt1 was detected in multiple organs/tissues of P. annectens, and this is the first report on the expression of bhmt1/Bhmt1 in animal skeletal muscle. The mRNA and protein expression levels of bhmt1/Bhmt1 were up-regulated in the liver of P. annectens during the induction and maintenance phases of aestivation, possibly to regulate the hepatic homocysteine concentration. The significant increase in hepatic Bhmt1 protein abundance during the arousal phase could be a response to increased cellular methylation for the purpose of tissue reconstruction. Unlike the liver, Bhmt1 expression in the kidney and muscle of P. annectens was regulated translationally, and its up-regulation could be crucial to prevent homocysteine accumulation.
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Affiliation(s)
- Jasmine L Y Ong
- Department of Biological Sciences, National University of Singapore, 10 Kent Ridge Road, Singapore 117543, Republic of Singapore
| | - Jia M Woo
- Department of Biological Sciences, National University of Singapore, 10 Kent Ridge Road, Singapore 117543, Republic of Singapore
| | - Kum C Hiong
- Department of Biological Sciences, National University of Singapore, 10 Kent Ridge Road, Singapore 117543, Republic of Singapore
| | - Biyun Ching
- Department of Biological Sciences, National University of Singapore, 10 Kent Ridge Road, Singapore 117543, Republic of Singapore
| | - Wai P Wong
- Department of Biological Sciences, National University of Singapore, 10 Kent Ridge Road, Singapore 117543, Republic of Singapore
| | - Shit F Chew
- Natural Sciences and Science Education, National Institute of Education, Nanyang Technological University, 1 Nanyang Walk, Singapore 637616, Republic of Singapore
| | - Yuen K Ip
- Department of Biological Sciences, National University of Singapore, 10 Kent Ridge Road, Singapore 117543, Republic of Singapore; The Tropical Marine Science Institute, National University of Singapore, Kent Ridge, Singapore 119227, Republic of Singapore.
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24
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Zhang B, Denomme MM, White CR, Leung KY, Lee MB, Greene NDE, Mann MRW, Trasler JM, Baltz JM. Both the folate cycle and betaine-homocysteine methyltransferase contribute methyl groups for DNA methylation in mouse blastocysts. FASEB J 2014; 29:1069-79. [PMID: 25466894 DOI: 10.1096/fj.14-261131] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The embryonic pattern of global DNA methylation is first established in the inner cell mass (ICM) of the mouse blastocyst. The methyl donor S-adenosylmethionine (SAM) is produced in most cells through the folate cycle, but only a few cell types generate SAM from betaine (N,N,N-trimethylglycine) via betaine-homocysteine methyltransferase (BHMT), which is expressed in the mouse ICM. Here, mean ICM cell numbers decreased from 18-19 in controls to 11-13 when the folate cycle was inhibited by the antifolate methotrexate and to 12-14 when BHMT expression was knocked down by antisense morpholinos. Inhibiting both pathways, however, much more severely affected ICM development (7-8 cells). Total SAM levels in mouse blastocysts decreased significantly only when both pathways were inhibited (from 3.1 to 1.6 pmol/100 blastocysts). DNA methylation, detected as 5-methylcytosine (5-MeC) immunofluorescence in isolated ICMs, was minimally affected by inhibition of either pathway alone but decreased by at least 45-55% when both BHMT and the folate cycle were inhibited simultaneously. Effects on cell numbers and 5-MeC levels in the ICM were completely rescued by methionine (immediate SAM precursor) or SAM. Both the folate cycle and betaine/BHMT appear to contribute to a methyl pool required for normal ICM development and establishing initial embryonic DNA methylation.
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Affiliation(s)
- Baohua Zhang
- *Ottawa Hospital Research Institute, Ottawa, Ontario, Canada; Departments of Obstetrics and Gynecology, and Cellular and Molecular Medicine, University of Ottawa Faculty of Medicine, Ottawa, Ontario, Canada; Department of Obstetrics and Gynecology, and Biochemistry, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada; Children's Health Research Institute, London, Ontario, Canada; Developmental Biology and Cancer Program, University College London Institute of Child Health, London, United Kingdom; Research Institute of the McGill University Health Centre, Montréal Children's Hospital, Montréal, Quebec, Canada; and Departments of Human Genetics, Pediatrics, and Pharmacology and Therapeutics, McGill University, Montréal, Quebec, Canada
| | - Michelle M Denomme
- *Ottawa Hospital Research Institute, Ottawa, Ontario, Canada; Departments of Obstetrics and Gynecology, and Cellular and Molecular Medicine, University of Ottawa Faculty of Medicine, Ottawa, Ontario, Canada; Department of Obstetrics and Gynecology, and Biochemistry, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada; Children's Health Research Institute, London, Ontario, Canada; Developmental Biology and Cancer Program, University College London Institute of Child Health, London, United Kingdom; Research Institute of the McGill University Health Centre, Montréal Children's Hospital, Montréal, Quebec, Canada; and Departments of Human Genetics, Pediatrics, and Pharmacology and Therapeutics, McGill University, Montréal, Quebec, Canada
| | - Carlee R White
- *Ottawa Hospital Research Institute, Ottawa, Ontario, Canada; Departments of Obstetrics and Gynecology, and Cellular and Molecular Medicine, University of Ottawa Faculty of Medicine, Ottawa, Ontario, Canada; Department of Obstetrics and Gynecology, and Biochemistry, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada; Children's Health Research Institute, London, Ontario, Canada; Developmental Biology and Cancer Program, University College London Institute of Child Health, London, United Kingdom; Research Institute of the McGill University Health Centre, Montréal Children's Hospital, Montréal, Quebec, Canada; and Departments of Human Genetics, Pediatrics, and Pharmacology and Therapeutics, McGill University, Montréal, Quebec, Canada
| | - Kit-Yi Leung
- *Ottawa Hospital Research Institute, Ottawa, Ontario, Canada; Departments of Obstetrics and Gynecology, and Cellular and Molecular Medicine, University of Ottawa Faculty of Medicine, Ottawa, Ontario, Canada; Department of Obstetrics and Gynecology, and Biochemistry, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada; Children's Health Research Institute, London, Ontario, Canada; Developmental Biology and Cancer Program, University College London Institute of Child Health, London, United Kingdom; Research Institute of the McGill University Health Centre, Montréal Children's Hospital, Montréal, Quebec, Canada; and Departments of Human Genetics, Pediatrics, and Pharmacology and Therapeutics, McGill University, Montréal, Quebec, Canada
| | - Martin B Lee
- *Ottawa Hospital Research Institute, Ottawa, Ontario, Canada; Departments of Obstetrics and Gynecology, and Cellular and Molecular Medicine, University of Ottawa Faculty of Medicine, Ottawa, Ontario, Canada; Department of Obstetrics and Gynecology, and Biochemistry, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada; Children's Health Research Institute, London, Ontario, Canada; Developmental Biology and Cancer Program, University College London Institute of Child Health, London, United Kingdom; Research Institute of the McGill University Health Centre, Montréal Children's Hospital, Montréal, Quebec, Canada; and Departments of Human Genetics, Pediatrics, and Pharmacology and Therapeutics, McGill University, Montréal, Quebec, Canada
| | - Nicholas D E Greene
- *Ottawa Hospital Research Institute, Ottawa, Ontario, Canada; Departments of Obstetrics and Gynecology, and Cellular and Molecular Medicine, University of Ottawa Faculty of Medicine, Ottawa, Ontario, Canada; Department of Obstetrics and Gynecology, and Biochemistry, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada; Children's Health Research Institute, London, Ontario, Canada; Developmental Biology and Cancer Program, University College London Institute of Child Health, London, United Kingdom; Research Institute of the McGill University Health Centre, Montréal Children's Hospital, Montréal, Quebec, Canada; and Departments of Human Genetics, Pediatrics, and Pharmacology and Therapeutics, McGill University, Montréal, Quebec, Canada
| | - Mellissa R W Mann
- *Ottawa Hospital Research Institute, Ottawa, Ontario, Canada; Departments of Obstetrics and Gynecology, and Cellular and Molecular Medicine, University of Ottawa Faculty of Medicine, Ottawa, Ontario, Canada; Department of Obstetrics and Gynecology, and Biochemistry, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada; Children's Health Research Institute, London, Ontario, Canada; Developmental Biology and Cancer Program, University College London Institute of Child Health, London, United Kingdom; Research Institute of the McGill University Health Centre, Montréal Children's Hospital, Montréal, Quebec, Canada; and Departments of Human Genetics, Pediatrics, and Pharmacology and Therapeutics, McGill University, Montréal, Quebec, Canada
| | - Jacquetta M Trasler
- *Ottawa Hospital Research Institute, Ottawa, Ontario, Canada; Departments of Obstetrics and Gynecology, and Cellular and Molecular Medicine, University of Ottawa Faculty of Medicine, Ottawa, Ontario, Canada; Department of Obstetrics and Gynecology, and Biochemistry, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada; Children's Health Research Institute, London, Ontario, Canada; Developmental Biology and Cancer Program, University College London Institute of Child Health, London, United Kingdom; Research Institute of the McGill University Health Centre, Montréal Children's Hospital, Montréal, Quebec, Canada; and Departments of Human Genetics, Pediatrics, and Pharmacology and Therapeutics, McGill University, Montréal, Quebec, Canada
| | - Jay M Baltz
- *Ottawa Hospital Research Institute, Ottawa, Ontario, Canada; Departments of Obstetrics and Gynecology, and Cellular and Molecular Medicine, University of Ottawa Faculty of Medicine, Ottawa, Ontario, Canada; Department of Obstetrics and Gynecology, and Biochemistry, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada; Children's Health Research Institute, London, Ontario, Canada; Developmental Biology and Cancer Program, University College London Institute of Child Health, London, United Kingdom; Research Institute of the McGill University Health Centre, Montréal Children's Hospital, Montréal, Quebec, Canada; and Departments of Human Genetics, Pediatrics, and Pharmacology and Therapeutics, McGill University, Montréal, Quebec, Canada
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25
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Ma H, Ning J, Jin X, Mao C, Bu X, Wang M, Liu H, Wang K, Lausted C, Hood L, Chen J, Hu Z. Betaine homocysteine methyltransferase (BHMT) as a specific and sensitive blood marker for acute liver injury. Biomarkers 2014; 19:578-84. [PMID: 25144858 DOI: 10.3109/1354750x.2014.951880] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Huailei Ma
- National Center for Nanoscience and Technology
BeijingP.R. China
| | - Jing Ning
- Beijing Proteome Research Center, Beijing Institute of Radiation Medicine
BeijingP.R. China
- Department of Laboratory Medicine, Beijing 307 Hospital
BeijingP.R. China
- Department of Laboratory Medicine, Affiliated Hospital, Academy of Military Medicine Science
BeijingP.R. China
- Department of Laboratory Medicine, Beijing Municipal Corps Hospital, Chinese People’s Armed Police Forces
BeijingP.R. China
| | - Xin Jin
- Department of Laboratory Medicine, Beijing 307 Hospital
BeijingP.R. China
| | - Chunming Mao
- Beijing Proteome Research Center, Beijing Institute of Radiation Medicine
BeijingP.R. China
| | - Xiangli Bu
- National Center for Nanoscience and Technology
BeijingP.R. China
| | - Miao Wang
- Department of Laboratory Medicine, Beijing 307 Hospital
BeijingP.R. China
| | - Huan Liu
- Beijing Proteome Research Center, Beijing Institute of Radiation Medicine
BeijingP.R. China
| | - Kun Wang
- Beijing Proteome Research Center, Beijing Institute of Radiation Medicine
BeijingP.R. China
- Division of Physical Biology & Bioimaging Center, Shanghai Institute of Applied Physics, Chinese Academy of Sciences ShanghaiP.R. China
| | | | - Leroy Hood
- Institute for Systems Biology, North Seattle
WAUSA
| | - Jiankui Chen
- Department of Laboratory Medicine, Beijing 307 Hospital
BeijingP.R. China
- Department of Laboratory Medicine, Affiliated Hospital, Academy of Military Medicine Science
BeijingP.R. China
| | - Zhiyuan Hu
- National Center for Nanoscience and Technology
BeijingP.R. China
- Beijing Proteome Research Center, Beijing Institute of Radiation Medicine
BeijingP.R. China
- Institute for Systems Biology, North Seattle
WAUSA
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26
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Padden J, Megger DA, Bracht T, Reis H, Ahrens M, Kohl M, Eisenacher M, Schlaak JF, Canbay AE, Weber F, Hoffmann AC, Kuhlmann K, Meyer HE, Baba HA, Sitek B. Identification of novel biomarker candidates for the immunohistochemical diagnosis of cholangiocellular carcinoma. Mol Cell Proteomics 2014; 13:2661-72. [PMID: 25034945 PMCID: PMC4188994 DOI: 10.1074/mcp.m113.034942] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
The aim of this study was the identification of novel biomarker candidates for the diagnosis of cholangiocellular carcinoma (CCC) and its immunohistochemical differentiation from benign liver and bile duct cells. CCC is a primary cancer that arises from the epithelial cells of bile ducts and is characterized by high mortality rates due to its late clinical presentation and limited treatment options. Tumorous tissue and adjacent non-tumorous liver tissue from eight CCC patients were analyzed by means of two-dimensional differential in-gel electrophoresis and mass-spectrometry-based label-free proteomics. After data analysis and statistical evaluation of the proteins found to be differentially regulated between the two experimental groups (fold change ≥ 1.5; p value ≤ 0.05), 14 candidate proteins were chosen for determination of the cell-type-specific expression profile via immunohistochemistry in a cohort of 14 patients. This confirmed the significant up-regulation of serpin H1, 14-3-3 protein sigma, and stress-induced phosphoprotein 1 in tumorous cholangiocytes relative to normal hepatocytes and non-tumorous cholangiocytes, whereas some proteins were detectable specifically in hepatocytes. Because stress-induced phosphoprotein 1 exhibited both sensitivity and specificity of 100%, an immunohistochemical verification examining tissue sections of 60 CCC patients was performed. This resulted in a specificity of 98% and a sensitivity of 64%. We therefore conclude that this protein should be considered as a potential diagnostic biomarker for CCC in an immunohistochemical application, possibly in combination with other candidates from this study in the form of a biomarker panel. This could improve the differential diagnosis of CCC and benign bile duct diseases, as well as metastatic malignancies in the liver.
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Affiliation(s)
- Juliet Padden
- From the ‡Medizinisches Proteom-Center, Ruhr-Universität Bochum, 44801 Bochum, Germany;
| | - Dominik A Megger
- From the ‡Medizinisches Proteom-Center, Ruhr-Universität Bochum, 44801 Bochum, Germany
| | - Thilo Bracht
- From the ‡Medizinisches Proteom-Center, Ruhr-Universität Bochum, 44801 Bochum, Germany
| | - Henning Reis
- ¶Institut für Pathologie, Universitätsklinikum Essen, Universität Duisburg-Essen, 45141 Essen, Germany
| | - Maike Ahrens
- From the ‡Medizinisches Proteom-Center, Ruhr-Universität Bochum, 44801 Bochum, Germany
| | - Michael Kohl
- From the ‡Medizinisches Proteom-Center, Ruhr-Universität Bochum, 44801 Bochum, Germany
| | - Martin Eisenacher
- From the ‡Medizinisches Proteom-Center, Ruhr-Universität Bochum, 44801 Bochum, Germany
| | - Jörg F Schlaak
- ‖Klinik für Gastroenterologie und Hepatologie, Universitätsklinikum Essen, 45141 Essen, Universität Duisburg-Essen, 45141 Essen, Germany
| | - Ali E Canbay
- ‖Klinik für Gastroenterologie und Hepatologie, Universitätsklinikum Essen, 45141 Essen, Universität Duisburg-Essen, 45141 Essen, Germany
| | - Frank Weber
- **Klinik für Allgemeinchirurgie, Viszeral- und Transplantationschirurgie, Universitätsklinikum Essen, Universität Duisburg-Essen, 45141 Essen, Germany
| | - Andreas-Claudius Hoffmann
- ‡‡Innere Klinik (Tumorforschung), Westdeutsches Tumorzentrum, Universitätsklinikum Essen, Universität Duisburg-Essen, 45141 Essen, Germany
| | - Katja Kuhlmann
- From the ‡Medizinisches Proteom-Center, Ruhr-Universität Bochum, 44801 Bochum, Germany
| | - Helmut E Meyer
- From the ‡Medizinisches Proteom-Center, Ruhr-Universität Bochum, 44801 Bochum, Germany; §§Leibniz Institute for Analytical Sciences - ISAS, 44139 Dortmund, Germany
| | - Hideo A Baba
- ¶Institut für Pathologie, Universitätsklinikum Essen, Universität Duisburg-Essen, 45141 Essen, Germany
| | - Barbara Sitek
- From the ‡Medizinisches Proteom-Center, Ruhr-Universität Bochum, 44801 Bochum, Germany;
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27
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Mládková J, Hladílková J, Diamond CE, Tryon K, Yamada K, Garrow TA, Jungwirth P, Koutmos M, Jiráček J. Specific potassium ion interactions facilitate homocysteine binding to betaine-homocysteine S
-methyltransferase. Proteins 2014; 82:2552-64. [DOI: 10.1002/prot.24619] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Revised: 05/24/2014] [Accepted: 05/28/2014] [Indexed: 12/17/2022]
Affiliation(s)
- Jana Mládková
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic; v.v.i., Flemingovo nám. 2, 166 10 Prague 6 Czech Republic
| | - Jana Hladílková
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic; v.v.i., Flemingovo nám. 2, 166 10 Prague 6 Czech Republic
| | - Carrie E. Diamond
- Department of Food Science and Human Nutrition; University of Illinois; Urbana Illinois 61801
| | - Katherine Tryon
- Department of Food Science and Human Nutrition; University of Illinois; Urbana Illinois 61801
| | - Kazuhiro Yamada
- Department of Biochemistry and Molecular Biology; Uniformed Services University of the Health Sciences; Bethesda Maryland 20814
| | - Timothy A. Garrow
- Department of Food Science and Human Nutrition; University of Illinois; Urbana Illinois 61801
| | - Pavel Jungwirth
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic; v.v.i., Flemingovo nám. 2, 166 10 Prague 6 Czech Republic
| | - Markos Koutmos
- Department of Biochemistry and Molecular Biology; Uniformed Services University of the Health Sciences; Bethesda Maryland 20814
| | - Jiří Jiráček
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic; v.v.i., Flemingovo nám. 2, 166 10 Prague 6 Czech Republic
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28
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Corbett HE, Dubé CD, Slow S, Lever M, Trasler JM, Baltz JM. Uptake of Betaine into Mouse Cumulus-Oocyte Complexes via the SLC7A6 Isoform of y+L Transporter1. Biol Reprod 2014; 90:81. [DOI: 10.1095/biolreprod.113.116939] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
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29
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Ganu R, Garrow T, Koutmos M, Rund L, Schook LB. Splicing variants of the porcine betaine-homocysteine S-methyltransferase gene: implications for mammalian metabolism. Gene 2013; 529:228-37. [PMID: 23948084 PMCID: PMC3894628 DOI: 10.1016/j.gene.2013.07.103] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2013] [Revised: 07/23/2013] [Accepted: 07/30/2013] [Indexed: 12/18/2022]
Abstract
Betaine-homocysteine S-methyltransferase (BHMT) activity is only detected in the liver of rodents, but in both the liver and kidney cortex of humans and pigs; therefore, the pig was chosen as a model to define the spatial and temporal expression of BHMT during development. During fetal development, a total of ten splice variants of bhmt were expressed at varying levels across a wide range of porcine tissues. Two variants contained an identical ORF that encoded a C-terminal truncated form of BHMT (tBHMT). The bhmt transcripts were expressed at significant levels in the liver and kidney from day 45 of gestation (G45) onward. The transcripts encoding tBHMT represented 5-13% of the total bhmt transcripts in G30 fetus, G45 liver, and adult liver and kidney cortex. The dominant structural feature of wild type BHMT is an (βα)8 barrel, however, a modeled structure of tBHMT suggests that this protein would assume a horseshoe fold and lack methyltransferase activity. Low BHMT activity was detected in the G30 fetus, and slightly increased levels of activity were observed in the liver from G45 and G90 fetuses. The bhmt promoter contained three key CpG sites, and methylation of these sites was significantly higher in adult lung compared to adult liver. The data reported herein suggest that genomic DNA methylation and variation of the 5' and 3' UTRs of bhmt transcripts are key regulators for the level of BHMT transcription and translation.
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Affiliation(s)
- Radhika Ganu
- Division of Nutritional Sciences, University of Illinois, Urbana, IL 61801
| | - Timothy Garrow
- Department of Food Science and Human Nutrition, University of Illinois, Urbana, IL 61801
| | - Markos Koutmos
- Department of Biochemistry and Molecular Biology, Uniformed Services University of the Health Sciences, Bethesda, MD 20814
| | - Laurie Rund
- Department of Animal Sciences, University of Illinois, Urbana, IL 61801
| | - Lawrence B. Schook
- Division of Nutritional Sciences, University of Illinois, Urbana, IL 61801
- Department of Animal Sciences, University of Illinois, Urbana, IL 61801
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30
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Neuman JC, Albright KA, Schalinske KL. Exercise prevents hyperhomocysteinemia in a dietary folate-restricted mouse model. Nutr Res 2013; 33:487-93. [PMID: 23746565 DOI: 10.1016/j.nutres.2013.04.008] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2012] [Revised: 04/09/2013] [Accepted: 04/13/2013] [Indexed: 02/08/2023]
Abstract
Hyperhomocysteinemia is a condition that results from altered methyl group metabolism and is associated with numerous pathological conditions. A number of nutritional and hormonal factors have been shown to influence circulating homocysteine concentrations; however, the impact of exercise on homocysteine and methyl group balance is not well understood. Our hypothesis was that exercise represents an effective means to prevent hyperhomocysteinemia in a folate-independent manner. The purpose of this study was to determine the influence of exercise on homocysteine metabolism in a dietary folate-restricted mouse model characterized by moderate hyperhomocysteinemia. Female outbred mice (12 weeks old) were assigned to either a sedentary or free-access wheel exercise group. Following a 4-week acclimation period, half of the mice in each group were provided a folate-restricted diet for 7-weeks prior to euthanasia and tissue collection. As expected, folate-restricted sedentary mice exhibited a 2-fold increase in plasma total homocysteine concentrations; however, exercise completely prevented the increase in circulating homocysteine concentrations. Moreover, exercise reduced plasma homocysteine concentrations 36% within the group fed only the control diet. The prevention of hyperhomocysteinemia by exercise appears, at least in part, to be the result of increased folate-independent homocysteine remethylation owing to a 2-fold increase in renal betaine homocysteine S-methyltransferase. To our knowledge, this is the first report demonstrating the prevention of hyperhomocysteinemia by exercise in a dietary folate-restriction model. Future research will be directed at determining if exercise can have a positive impact on other nutritional, hormonal, and genetic models of hyperhomocysteinemia relevant to humans.
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Affiliation(s)
- Joshua C Neuman
- Department of Food Science and Human Nutrition, Iowa State University, Ames, Iowa 50011, USA
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31
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Mustafa M, Hussain S, Qureshi S, Malik SA, Kazmi AR, Naeem M. Study of the effect of antiviral therapy on homocysteinemia in hepatitis C virus- infected patients. BMC Gastroenterol 2012; 12:117. [PMID: 22925702 PMCID: PMC3564702 DOI: 10.1186/1471-230x-12-117] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2012] [Accepted: 08/22/2012] [Indexed: 01/27/2023] Open
Abstract
BACKGROUND Hepatitis C virus (HCV) infection is one of the leading causes of chronic liver disease (CLD). About 80% of those exposed to the virus develop a chronic infection. Hyperhomocysteinemia, which is an independent risk factor for atherosclerotic vascular disease and thromboembolism, may develop in HCV-infected patients although altered alanine amino transferase (ALT) enzyme levels are generally associated with damage to liver cells. The gold standard therapy for chronic hepatitis C patients is pegylated interferon combined with an anti-viral drug (ribavirin). The current study aimed to investigate the effect of antiviral therapy on plasma homocysteine (Hcy) levels in HCV patients in addition to other parameters. METHODS 532 HCV-infected patients and 70 healthy controls were recruited for the study. All patients were subjected to laboratory investigations including HCV-RNA levels, complete blood cell counts, serum levels of homocysteine, ALT, alkaline phosphatase (ALP), lipid profile and liver ultrasonographic examination. The outcome of treatment with pegylated interferon α plus ribavirin treatment and sustained virologic response (SVR) was determined 6-9 months post-therapy. RESULTS Hyperhomocysteinemia was found in 91.35% of HCV-infected patients. The difference in plasma Hcy concentrations reached statistical significance between the patient and control groups. ALT, cholesterol and triglycerides (TGs) levels were found higher than normal in the patients group. After receiving a combined therapy for 24 weeks, 43.66% patients showed an SVR (responders); 30.98% patients were non-responders while 25.35% patients initially responded to therapy but again retrieved positive status of HCV infection six months post-therapy (relapse-cirrhotic patients). The mean levels of plasma Hcy, ALT and ALP were significantly reduced in responders within 10 weeks of therapy when compared with non-responders and relapse-cirrhotic patients. CONCLUSION Elevated homocysteine levels in serum due to HCV infection can be reduced to normal range with the standard interferon α plus ribavirin treatment. This study highlights the significance of the measurement of serum homocysteine levels in the diagnosis and monitoring of HCV infection treatment in addition to other laboratory parameters.
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Affiliation(s)
- Mubin Mustafa
- Department of Biochemistry, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan
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32
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Lee MB, Kooistra M, Zhang B, Slow S, Fortier AL, Garrow TA, Lever M, Trasler JM, Baltz JM. Betaine homocysteine methyltransferase is active in the mouse blastocyst and promotes inner cell mass development. J Biol Chem 2012; 287:33094-103. [PMID: 22847001 DOI: 10.1074/jbc.m112.365478] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Methyltransferases are an important group of enzymes with diverse roles that include epigenetic gene regulation. The universal donor of methyl groups for methyltransferases is S-adenosylmethionine (AdoMet), which in most cells is synthesized using methyl groups carried by a derivative of folic acid. Another mechanism for AdoMet synthesis uses betaine as the methyl donor via the enzyme betaine-homocysteine methyltransferase (BHMT, EC 2.1.1.5), but it has been considered to be significant only in liver. Here, we show that mouse preimplantation embryos contain endogenous betaine; Bhmt mRNA is first expressed at the morula stage; BHMT is abundant at the blastocyst stage but not other preimplantation stages, and BHMT activity is similarly detectable in blastocyst homogenates but not those of two-cell or morula stage embryos. Knockdown of BHMT protein levels and reduction of enzyme activity using Bhmt-specific antisense morpholinos or a selective BHMT inhibitor resulted in decreased development of embryos to the blastocyst stage in vitro and a reduction in inner cell mass cell number in blastocysts. The detrimental effects of BHMT knockdown were fully rescued by the immediate methyl-carrying product of BHMT, methionine. A physiological role for betaine and BHMT in blastocyst viability was further indicated by increased fetal resorption following embryo transfer of BHMT knockdown blastocysts versus control. Thus, mouse blastocysts are unusual in being able to generate AdoMet not only by the ubiquitous folate-dependent mechanism but also from betaine metabolized by BHMT, likely a significant pool of methyl groups in blastocysts.
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Affiliation(s)
- Martin B Lee
- Ottawa Hospital Research Institute, Ottawa, Ontario K1Y4E9, Canada
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33
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Fridman O, Morales AV, Bortoni LE, Turk-Noceto PC, Prieto EA. Corticoadrenal activity in rat regulates betaine-homocysteine S-methyltransferase expression with opposite effects in liver and kidney. J Biosci 2012; 37:115-23. [PMID: 22357209 DOI: 10.1007/s12038-011-9171-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
Abstract
Betaine-homocysteine S-methyltransferase (BHMT) is an enzyme that converts homocysteine (Hcy) to methionine using betaine as a methyl donor. Betaine also acts as osmolyte in kidney medulla, protecting cells from high extracellular osmolarity. Hepatic BHMT expression is regulated by salt intake. Hormones, particularly corticosteroids, also regulate BHMT expression in rat liver. We investigated to know whether the corticoadrenal activity plays a role in kidney BHMT expression. BHMT activity in rat kidneys is several orders of magnitude lower than in rat livers and only restricted to the renal cortex. This study confirms that corticosteroids stimulate BHMT activity in the liver and, for the first time in an animal model, also up-regulate the BHMT gene expression. Besides, unlike the liver, corticosteroids in rat kidney down-regulate BHMT expression and activity. Given that the classical effect of adrenocortical activity on the kidney is associated with sodium and water re-absorption by the distal tubule leading to volume expansion, by promoting lesser use of betaine as a methyl donor, corticosteroids would preserve betaine for its other role as osmoprotectant against changes in the extracellular osmotic conditions. We conclude that corticosteroids are, at least in part, responsible for the inhibition of BHMT expression and activity in rat kidneys.
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Affiliation(s)
- Osvaldo Fridman
- Centro de Altos Estudios en Ciencias Humanas y de la Salud, Universidad Abierta Interamericana (UAI), Buenos Aires, Argentina.
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34
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Teng YW, Ellis JM, Coleman RA, Zeisel SH. Mouse betaine-homocysteine S-methyltransferase deficiency reduces body fat via increasing energy expenditure and impairing lipid synthesis and enhancing glucose oxidation in white adipose tissue. J Biol Chem 2012; 287:16187-98. [PMID: 22362777 DOI: 10.1074/jbc.m111.303255] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Betaine-homocysteine S-methyltransferase (BHMT) catalyzes the synthesis of methionine from homocysteine. In our initial report, we observed a reduced body weight in Bhmt(-/-) mice. We initiated this study to investigate the potential role of BHMT in energy metabolism. Compared with the controls (Bhmt(+/+)), Bhmt(-/-) mice had less fat mass, smaller adipocytes, and better glucose and insulin sensitivities. Compared with the controls, Bhmt(-/-) mice had increased energy expenditure, with no changes in food intake, fat uptake or absorption, or in locomotor activity. The reduced adiposity in Bhmt(-/-) mice was not due to hyperthermogenesis. Bhmt(-/-) mice failed to maintain a normal body temperature upon cold exposure because of limited fuel supplies. In vivo and ex vivo tests showed that Bhmt(-/-) mice had normal lipolytic function. The rate of (14)C-labeled fatty acid incorporated into [(14)C]triacylglycerol was the same in Bhmt(+/+) and Bhmt(-/-) gonadal fat depots (GWAT), but it was 62% lower in Bhmt(-/-) inguinal fat depots (IWAT) compared with that of Bhmt(+/+) mice. The rate of (14)C-labeled fatty acid oxidation was the same in both GWAT and IWAT from Bhmt(+/+) and Bhmt(-/-) mice. At basal level, Bhmt(-/-) GWAT had the same [(14)C]glucose oxidation as did the controls. When stimulated with insulin, Bhmt(-/-) GWAT oxidized 2.4-fold more glucose than did the controls. Compared with the controls, the rate of [(14)C]glucose oxidation was 2.4- and 1.8-fold higher, respectively, in Bhmt(-/-) IWAT without or with insulin stimulus. Our results show for the first time a role for BHMT in energy homeostasis.
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Affiliation(s)
- Ya-Wen Teng
- Department of Nutrition, School of Public Health, University of North Carolina, Chapel Hill, North Carolina 27599, USA
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35
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Zhou Y, Holmseth S, Hua R, Lehre AC, Olofsson AM, Poblete-Naredo I, Kempson SA, Danbolt NC. The betaine-GABA transporter (BGT1, slc6a12) is predominantly expressed in the liver and at lower levels in the kidneys and at the brain surface. Am J Physiol Renal Physiol 2012; 302:F316-28. [DOI: 10.1152/ajprenal.00464.2011] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
The Na+- and Cl−-dependent GABA-betaine transporter (BGT1) has received attention mostly as a protector against osmolarity changes in the kidney and as a potential controller of the neurotransmitter GABA in the brain. Nevertheless, the cellular distribution of BGT1, and its physiological importance, is not fully understood. Here we have quantified mRNA levels using TaqMan real-time PCR, produced a number of BGT1 antibodies, and used these to study BGT1 distribution in mice. BGT1 (protein and mRNA) is predominantly expressed in the liver (sinusoidal hepatocyte plasma membranes) and not in the endothelium. BGT1 is also present in the renal medulla, where it localizes to the basolateral membranes of collecting ducts (particularly at the papilla tip) and the thick ascending limbs of Henle. There is some BGT1 in the leptomeninges, but brain parenchyma, brain blood vessels, ependymal cells, the renal cortex, and the intestine are virtually BGT1 deficient in 1- to 3-mo-old mice. Labeling specificity was assured by processing tissue from BGT1-deficient littermates in parallel as negative controls. Addition of 2.5% sodium chloride to the drinking water for 48 h induced a two- to threefold upregulation of BGT1, tonicity-responsive enhancer binding protein, and sodium- myo-inositol cotransporter 1 (slc5a3) in the renal medulla, but not in the brain and barely in the liver. BGT1-deficient and wild-type mice appeared to tolerate the salt treatment equally well, possibly because betaine is one of several osmolytes. In conclusion, this study suggests that BGT1 plays its main role in the liver, thereby complementing other betaine-transporting carrier proteins (e.g., slc6a20) that are predominantly expressed in the small intestine or kidney rather than the liver.
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Affiliation(s)
- Y. Zhou
- Department of Anatomy, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - S. Holmseth
- Department of Anatomy, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - R. Hua
- Department of Anatomy, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - A. C. Lehre
- Department of Anatomy, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - A. M. Olofsson
- Department of Anatomy, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - I. Poblete-Naredo
- Departamento de Genética y Biología Molecular, Centro de Investigación y de studios Avanzados del Instituto Politécnico Nacional, México City, Mexico; and
| | - S. A. Kempson
- Department of Cellular and Integrative Physiology, Indiana University School of Medicine, Indianapolis, Indiana
| | - N. C. Danbolt
- Department of Anatomy, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
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Williams KT, Schalinske KL. Tissue-specific alterations of methyl group metabolism with DNA hypermethylation in the Zucker (type 2) diabetic fatty rat. Diabetes Metab Res Rev 2012; 28:123-31. [PMID: 21818837 DOI: 10.1002/dmrr.1281] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
BACKGROUND Altered methyl group and homocysteine metabolism were tissue-specific, persistent, and preceded hepatic DNA hypomethylation in type 1 diabetic rats. Similar metabolic perturbations have been shown in the Zucker (type 2) diabetic fatty (ZDF) rat in the pre-diabetic and early diabetic stages, but tissue specificity and potential impact on epigenetic marks are unknown, particularly during pathogenesis. METHODS ZDF (fa/fa) and lean (+/?) control rats were killed at 12 and 21 weeks of age, representing early and advanced diabetic conditions. Blood and tissues were analysed with respect to methyl group and homocysteine metabolism, including DNA methylation. RESULTS At 12 weeks, hepatic glycine N-methyltransferase (GNMT), methionine synthase, and cystathionine β-synthase (CBS) activity and/or abundance were increased in ZDF rats. At 21 weeks, GNMT activity was increased in liver and kidney; however, only hepatic CBS protein abundance (12 weeks) and betaine-homocysteine S-methyltransferase mRNA expression (21 weeks) were significantly elevated (78 and 100%, respectively). Hepatic phosphatidylethanolamine N-methyltransferase expression was also elevated in the ZDF rat. Homocysteine concentrations were decreased in plasma and kidney, but not in liver, at 12 and 21 weeks. In contrast to hepatic DNA hypomethylation in the type 1 diabetic rat, genomic DNA was hypermethylated at 12 and 21 weeks in the liver of ZDF rats, concomitant with an increase in DNA methyltransferase 1 expression at 21 weeks. CONCLUSIONS The pathogenesis of type 2 diabetes in the ZDF rat was associated with tissue and disease stage-specific aberrations of methyl group and homocysteine metabolism, with persistent hepatic global DNA hypermethylation.
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Affiliation(s)
- Kelly T Williams
- Interdepartmental Graduate Program in Nutritional Sciences, Department of Food Science and Human Nutrition, Iowa State University, Ames, IA 50011, USA
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Hoffman JR, Ratamess NA, Kang J, Gonzalez AM, Beller NA, Craig SAS. Effect of 15 days of betaine ingestion on concentric and eccentric force outputs during isokinetic exercise. J Strength Cond Res 2011; 25:2235-41. [PMID: 21747291 DOI: 10.1519/jsc.0b013e3182162530] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
The purpose of this study was to examine the efficacy of 15 days of betaine supplementation on peak concentric (CON) and eccentric (ECC) force during isokinetic exercise in active college-aged men. Eleven men volunteered for this study (21.7 ± 5.1 years; height: 178.5 ± 6.4 cm; body mass: 79.8 ± 10.3 kg). Subjects were randomly assigned to either a supplement (BET) or placebo (PL) group. Supplementation occurred for 15 days. Subjects reported to the Human Performance Laboratory on 5 occasions during this period, separated by 72 hours, for a testing and exercise session on an isokinetic chest press device. After each exercise protocol, subjects rated their fatigue and muscle soreness on a 15-cm visual analog scale. Subjects then consumed no daily BET for 4 weeks but maintained familiarity with the exercise device once per week. After the washout period, subjects resumed the BET protocol using the opposite drink and repeated the same 15-day protocol. No differences were noted in maximum CON force output between pre (335.9 ± 78.3 and 321.6 ± 63.6 N) and post (330.3 ± 74.8 and 330.2 ± 71.6 N) workouts in both BET and PL, respectively. In addition, no differences were noted in maximum ECC force output between pre (352.0 ± 90.6 and 324.4 ± 85.2 N) and post (353.2 ± 98.2 and 366.9 ± 128.5 N) workouts in BET and PL, respectively. No differences in subjective measures of soreness and fatigue were seen, but a significant reduction in Δ fatigue was observed in BET compared to PL. In conclusion, 15 days of betaine supplementation did not increase peak CON or ECC force outputs during an isokinetic chest press but did appear to reduce subjective measures of fatigue to the exercise protocol.
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Affiliation(s)
- Jay R Hoffman
- Sport and Exercise Science, The University of Central Florida, Orlando, Florida, USA.
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Pellanda H, Namour F, Fofou-Caillierez M, Bressenot A, Alberto JM, Chéry C, Ayav A, Bronowicki JP, Guéant JL, Forges T. A splicing variant leads to complete loss of function of betaine-homocysteine methyltransferase (BHMT) gene in hepatocellular carcinoma. Int J Biochem Cell Biol 2011; 44:385-92. [PMID: 22138536 DOI: 10.1016/j.biocel.2011.11.014] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2011] [Revised: 11/07/2011] [Accepted: 11/17/2011] [Indexed: 02/01/2023]
Abstract
The remethylation of homocyteine into methionine is catalyzed either by methionine synthase (MTR) or by betaine-homocysteine methyltransferase (BHMT), in the liver. Choline/betaine deficiency and impaired BHMT pathway have been associated with hepatocellular carcinogenesis, in animal models. The molecular mechanisms that impair the BHMT pathway are unknown. We aimed to investigate BHMT, BHMT2, and MTR expression in HepG2 cells and human hepatocarcinoma tissues. Transcripts were quantified by RT-qPCR and splicing was assessed by analysis of exon junctions and sequencing of variants. Protein expression was studied by Western Blot, immunohistochemistry and enzyme activity. Tumor tissue was compared with surrounding healthy tissue. RT-qPCR of HepG2 cells and of tumor samples showed a strong decrease of transcripts of BHMT and BHMT2, compared to normal. MTR transcript levels were not different. The decreased BHMT expression resulted from the transcription of a splicing variant that produced a frameshift in exon 4, with a premature termination codon in exon 5 and a loss of function of the gene. This splicing variant did not fit with any mechanism resulting from known splicing consensus sequences and was not detected in normal adult and fetal liver. Consistently, BHMT activity was abolished in HepG2 and protein expression was not detectable in HepG2 and in 5 of the 6 tumor samples, compared to normal tissues. In conclusion, a transcription variant of exon 4 produces a loss of function of BHMT in human hepatocarcinoma. Whether this abnormal transcription of BHMT is part or consequence of liver carcinogenesis should deserve further investigations.
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Affiliation(s)
- Hélène Pellanda
- INSERM U954 Nutrition, Genetics, and Environmental Risk Exposure, Faculté de Médecine, Nancy Université, 9 Avenue de Forêt de Haye, 54500 Vandoeuvre Nancy, France
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Katko M, Zavaczki E, Jeney V, Paragh G, Balla J, Varga Z. Homocysteine metabolism in peripheral blood mononuclear cells: evidence for cystathionine beta-synthase activity in resting state. Amino Acids 2011; 43:317-26. [PMID: 21938399 DOI: 10.1007/s00726-011-1080-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2011] [Accepted: 09/08/2011] [Indexed: 01/30/2023]
Abstract
Activated peripheral blood mononuclear cells (PBMC) release homocysteine and possess cystathionine β-synthase (CBS) activity; however, it was thought that there is no CBS in resting state. Previously, we found that nickel decreased intracellular homocysteine concentration in un-stimulated (e.g. resting) PBMC, suggesting that resting PBMC might also have active homocysteine metabolism. Here, we demonstrated that un-stimulated PBMC synthesize (incorporate L-[methyl-14C]methionine to DNA, lipids and proteins), release (increase extracellular homocysteine), and metabolize homocysteine. Intracellular homocysteine concentration varied with incubation time, depending on extracellular concentrations of methionine, homocysteine, and glutathione. Methionine synthase activity was constant and independent of thiol concentrations. In Western blot, CBS protein was clearly identified in freshly isolated PBMC. CBS protein level and activity increased with incubation time, upon stimulation, and similar to intracellular homocysteine, depending on intra- and extracellular homocysteine and glutathione concentrations. According to our knowledge, this is the first evidence that certifies homocysteine metabolism and regulatory role of CBS activity to keep balanced intracellular homocysteine level in resting PBMC. Homocysteine, released by PBMC, in turn can modulate its functions contributing to the development of hyperhomocysteinemia-induced diseases.
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Affiliation(s)
- Monika Katko
- First Department of Medicine, Medical and Health Science Center, University of Debrecen, Nagyerdei krt. 98, H-4012, Debrecen, P.O. Box 19, Hungary
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Øverbye A, Sætre F, Hagen LK, Johansen HT, Seglen PO. Autophagic activity measured in whole rat hepatocytes as the accumulation of a novel BHMT fragment (p10), generated in amphisomes by the asparaginyl proteinase, legumain. Autophagy 2011; 7:1011-27. [PMID: 21610319 DOI: 10.4161/auto.7.9.16436] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
To investigate the stepwise autophagic-lysosomal processing of hepatocellular proteins, the abundant cytosolic enzyme, betaine:homocysteine methyltransferase (BHMT) was used as a probe. Full-length (45 kDa) endogenous BHMT was found to be cleaved in an autophagy-dependent (3-methyladenine-sensitive) manner in isolated rat hepatocytes to generate a novel N-terminal 10-kDa fragment (p10) identified and characterized by mass spectrometry. The cleavage site was consistent with cleavage by the asparaginyl proteinase, legumain and indeed a specific inhibitor of this enzyme (AJN-230) was able to completely suppress p10 formation in intact cells, causing instead accumulation of a 42-kDa intermediate. To prevent further degradation of p10 or p42 by the cysteine proteinases present in autophagic vacuoles, the proteinase inhibitor leupeptin had to be present. Asparagine, an inhibitor of amphisome-lysosome fusion, did not detectably impede either p42 or p10 formation, indicating that BHMT processing primarily takes place in amphisomes rather than in lysosomes. Lactate dehydrogenase (LDH) was similarly degraded primarily in amphisomes by leupeptin-sensitive proteolysis, but some additional leupeptin-resistant LDH degradation in lysosomes was also indicated. The autophagic sequestration of BHMT appeared to be nonselective, as the accumulation of p10 (in the presence of leupeptin) or of its precursors (in the additional presence of AJN-230) proceeded at approximately the same rate as the model autophagic cargo, LDH. The complete lack of a cytosolic background makes p10 suitable for use in a "fragment assay" of autophagic activity in whole cells. Incubation of hepatocytes with ammonium chloride, which neutralizes amphisomes as well as lysosomes, caused rapid, irreversible inhibition of legumain activity and stopped all p10 formation. The availability of several methods for selective targeting of legumain in intact cells may facilitate functional studies of this enigmatic enzyme, and perhaps suggest novel ways to reduce its contribution to cancer cell metastasis or autoimmune disease.
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Affiliation(s)
- Anders Øverbye
- Department of Cell Biology, Institute for Cancer Research, The Norwegian Radium Hospital, Oslo University Hospital, Nydalen, Oslo, Norway
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41
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Teng YW, Mehedint MG, Garrow TA, Zeisel SH. Deletion of betaine-homocysteine S-methyltransferase in mice perturbs choline and 1-carbon metabolism, resulting in fatty liver and hepatocellular carcinomas. J Biol Chem 2011; 286:36258-67. [PMID: 21878621 DOI: 10.1074/jbc.m111.265348] [Citation(s) in RCA: 148] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Betaine-homocysteine S-methyltransferase (BHMT) uses betaine to catalyze the conversion of homocysteine (Hcy) to methionine. There are common genetic polymorphisms in the BHMT gene in humans that can alter its enzymatic activity. We generated the first Bhmt(-/-) mouse to model the functional effects of mutations that result in reduced BHMT activity. Deletion of Bhmt resulted in a 6-fold increase (p < 0.01) in hepatic and an 8-fold increase (p < 0.01) in plasma total Hcy concentrations. Deletion of Bhmt resulted in a 43% reduction in hepatic S-adenosylmethionine (AdoMet) (p < 0.01) and a 3-fold increase in hepatic S-adenosylhomocysteine (AdoHcy) (p < 0.01) concentrations, resulting in a 75% reduction in methylation potential (AdoMet:AdoHcy) (p < 0.01). Bhmt(-/-) mice accumulated betaine in most tissues, including a 21-fold increase in the liver concentration compared with wild type (WT) (p < 0.01). These mice had lower concentrations of choline, phosphocholine, glycerophosphocholine, phosphatidylcholine, and sphingomyelin in several tissues. At 5 weeks of age, Bhmt(-/-) mice had 36% lower total hepatic phospholipid concentrations and a 6-fold increase in hepatic triacyglycerol concentrations compared with WT (p < 0.01), which was due to a decrease in the secretion of very low density lipoproteins. At 1 year of age, 64% of Bhmt(-/-) mice had visible hepatic tumors. Histopathological analysis revealed that Bhmt(-/-) mice developed hepatocellular carcinoma or carcinoma precursors. These results indicate that BHMT has an important role in Hcy, choline, and one-carbon homeostasis. A lack of Bhmt also affects susceptibility to fatty liver and hepatocellular carcinoma. We suggest that functional polymorphisms in BHMT that significantly reduce activity may have similar effects in humans.
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Affiliation(s)
- Ya-Wen Teng
- Department of Nutrition, School of Public Health, University of North Carolina, Chapel Hill, North Carolina 27599, USA
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42
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Creatine but not betaine supplementation increases muscle phosphorylcreatine content and strength performance. Amino Acids 2011; 42:2299-305. [DOI: 10.1007/s00726-011-0972-5] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2011] [Accepted: 06/27/2011] [Indexed: 01/26/2023]
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Schiff M, Benoist JF, Tilea B, Royer N, Giraudier S, Ogier de Baulny H. Isolated remethylation disorders: do our treatments benefit patients? J Inherit Metab Dis 2011; 34:137-45. [PMID: 20490923 DOI: 10.1007/s10545-010-9120-8] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2010] [Revised: 04/17/2010] [Accepted: 04/20/2010] [Indexed: 10/19/2022]
Abstract
Deficiency of 5,10-methylenetetrahydrofolate reductase (MTHFR), the very rare methionine synthase reductase (CblE) and methionine synthase (CblG) defects, and the recently identified CblD-variant-1 defect are primary remethylation defects characterized by an isolated defect in methionine synthesis without methylmalonic aciduria. The clinical signs are mainly neurological, and hematological signs are seen in CblE, CblG, and CblD-variant-1 defects. Patients with neonatal or early-onset disease exhibit acute neurological distress. Infants and children have unspecific mental retardation, often with acquired microcephaly. Without appropriate therapy, they may experience acute or rapidly progressive neurological deterioration, which may be fatal. Adolescents and adults show normal development or mild developmental delay initially and then experience rapid neurological or behavioral deterioration. A few patients may have signs of subacute combined degeneration of the spinal cord. Adults may be asymptomatic or present with isolated thromboembolism. All patients with suspected remethylation disorders should receive emergency treatment with parenteral administration of hydroxocobalamin and folate supplements combined with betaine orally. The long-term treatment of CblE, CblG, and CblD-variant-1 defects consists of parenterally administered hydroxocobalamin and orally administered folate and betaine supplements, whereas patients with MTHFR deficiency require long-term oral folate and betaine supplements. Long-term oral methionine therapy should also be considered. Early treatment may lead to a favorable outcome with developmental recovery and prevention of further neurological deterioration. In contrast, most late-treated patients have severe and irreversible neuromotor impairments. Hematological abnormalities are easily corrected.
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Affiliation(s)
- Manuel Schiff
- Reference Center for Metabolic Disease, Robert Debré University Hospital, Paris, France.
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44
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Ganu RS, Garrow TA, Sodhi M, Rund LA, Schook LB. Molecular characterization and analysis of the porcine betaine homocysteine methyltransferase and betaine homocysteine methyltransferase-2 genes. Gene 2010; 473:133-8. [PMID: 21156199 DOI: 10.1016/j.gene.2010.11.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2010] [Revised: 11/25/2010] [Accepted: 11/29/2010] [Indexed: 02/03/2023]
Abstract
Betaine homocysteine methyltransferase (BHMT) and BHMT-2 enzymes methylate homocysteine to form methionine using betaine and S-methylmethionine, respectively. These activities are observed only in the liver of adult rodents, but in adult humans and pigs these activities are detected in both the liver and kidney, indicating the pig is a more appropriate model for studying the biochemical and physiological roles of these enzymes in human biology. Porcine BHMT and BHMT-2 cDNAs were cloned and sequenced, and their 5' and 3' UTR were amplified using RLM-RACE. The BHMT transcript had significantly longer 5' and 3' UTRs than BHMT-2. The pig BHMT and BHMT-2 genes span approximately 26 and 16kb, respectively, and both genes have 8 exons. The deduced amino acid sequences of BHMT and BHMT-2 contain 407 and 363 amino acids, respectively, and shared 78% amino acid identity. No promoter element (TATA or CAAT box) was observed for either BHMT or BHMT-2, although a CpG island surrounding the promoter and transcriptional start site was observed in both genes implying that methylation could regulate their expression. Using qPCR, it was determined that BHMT and BHMT-2 transcripts are very abundant in liver and kidney cortex, whereas the expression is significantly less in other tissues. These findings confirm that the expression pattern of BHMT and BHMT-2 genes in pigs is similar to humans, supporting the use of the pig as an animal model to study the genetics and regulation of BHMT and BHMT-2 expression.
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Affiliation(s)
- Radhika S Ganu
- Division of Nutritional Sciences, University of Illinois at Urbana Champaign, 1201 W. Gregory Dr., Urbana, IL 61801, USA
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46
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Strakova J, Williams KT, Gupta S, Schalinske KL, Kruger WD, Rozen R, Jiracek J, Li L, Garrow TA. Dietary intake of S-(alpha-carboxybutyl)-DL-homocysteine induces hyperhomocysteinemia in rats. Nutr Res 2010; 30:492-500. [PMID: 20797482 PMCID: PMC2929918 DOI: 10.1016/j.nutres.2010.06.017] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2010] [Revised: 06/30/2010] [Accepted: 06/30/2010] [Indexed: 11/16/2022]
Abstract
Betaine homocysteine S-methyltransferase (BHMT) catalyzes the transfer of a methyl group from betaine to homocysteine (Hcy), forming dimethylglycine and methionine. We previously showed that inhibiting BHMT in mice by intraperitoneal injection of S-(alpha-carboxybutyl)-DL-homocysteine (CBHcy) results in hyperhomocysteinemia. In the present study, CBHcy was fed to rats to determine whether it could be absorbed and cause hyperhomocysteinemia as observed in the intraperitoneal administration of the compound in mice. We hypothesized that dietary administered CBHcy will be absorbed and will result in the inhibition of BHMT and cause hyperhomocysteinemia. Rats were meal-fed every 8 hours an L-amino acid-defined diet either containing or devoid of CBHcy (5 mg per meal) for 3 days. The treatment decreased liver BHMT activity by 90% and had no effect on methionine synthase, methylenetetrahydrofolate reductase, phosphatidylethanolamine N-methyltransferase, and CTP:phosphocholine cytidylyltransferase activities. In contrast, cystathionine beta-synthase activity and immunodetectable protein decreased (56% and 26%, respectively) and glycine N-methyltransferase activity increased (52%) in CBHcy-treated rats. Liver S-adenosylmethionine levels decreased by 25% in CBHcy-treated rats, and S-adenosylhomocysteine levels did not change. Furthermore, plasma choline decreased (22%) and plasma betaine increased (15-fold) in CBHcy-treated rats. The treatment had no effect on global DNA and CpG island methylation, liver histology, and plasma markers of liver damage. We conclude that CBHcy-mediated BHMT inhibition causes an elevation in total plasma Hcy that is not normalized by the folate-dependent conversion of Hcy to methionine. Furthermore, metabolic changes caused by BHMT inhibition affect cystathionine beta-synthase and glycine N-methyltransferase activities, which further deteriorate plasma Hcy levels.
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Affiliation(s)
- Jana Strakova
- Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Kelly T. Williams
- Department of Food Science and Human Nutrition, Iowa State University, Ames, IA 50011, USA
| | - Sapna Gupta
- Division of Population Science, Fox Chase Cancer Center, Philadelphia, PA 19111, USA
| | - Kevin L. Schalinske
- Department of Food Science and Human Nutrition, Iowa State University, Ames, IA 50011, USA
| | - Warren D. Kruger
- Division of Population Science, Fox Chase Cancer Center, Philadelphia, PA 19111, USA
| | - Rima Rozen
- Departments of Human Genetics and Pediatrics, McGill University Health Centre-Montreal Children's Hospital, Montreal, Quebec, Canada
| | - Jiri Jiracek
- Biological Chemistry Department, Institute of Organic Chemistry and Biochemistry, Academy of Science of the Czech Republic, Prague 166 10, Czech Republic
| | - Lucas Li
- Metabolomics Center, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Timothy A. Garrow
- Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
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Schiff M, Ogier de Baulny H, Bard G, Barlogis V, Hamel C, Moat SJ, Odent S, Shortland G, Touati G, Giraudier S. Should transcobalamin deficiency be treated aggressively? J Inherit Metab Dis 2010; 33:223-9. [PMID: 20352340 DOI: 10.1007/s10545-010-9074-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2010] [Revised: 02/25/2010] [Accepted: 03/01/2010] [Indexed: 12/24/2022]
Abstract
Transcobalamin (transcobalamin II, TC) transports plasma vitamin B(12) (cobalamin, Cbl) into cells. TC deficiency is a rare autosomal recessive disorder causing intracellular Cbl depletion, which in turn causes megaloblastic bone marrow failure, accumulation of homocysteine and methylmalonic acid, and methionine depletion. The clinical presentation reflects intracellular Cbl defects, with early-onset failure to thrive with gastrointestinal symptoms, pancytopenia, and megaloblastic anemia, sometimes followed by neurological complications. We report the clinical, biological, and molecular findings and the outcome in five TC-deficient patients. The three treated early had an initial favorable outcome, whereas the two treated inadequately had late-onset severe neuro-ophthalmological impairment. Even if the natural course of the disease over time might also result in late-onset symptoms in the aggressively treated patients, these data emphasize that TC deficiency is a severe disorder requiring early detection and probably long-term aggressive therapy. Mutation analysis revealed six unreported mutations in the TCN2 gene. In silico structural analysis showed that these mutations disrupt the Cbl-TC interaction domain and/or the putative transcobalamin-transcobalamin receptor interaction domain.
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Affiliation(s)
- Manuel Schiff
- Service de Neuropédiatrie & Maladies Métaboliques, Centre de référence Maladies Métaboliques, CHU Robert Debré, APHP, Paris, France.
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Folate and One-Carbon Metabolism and Its Impact on Aberrant DNA Methylation in Cancer. EPIGENETICS AND CANCER, PART B 2010; 71:79-121. [DOI: 10.1016/b978-0-12-380864-6.00004-3] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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49
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Obeid R, Herrmann W. Homocysteine and lipids: S-adenosyl methionine as a key intermediate. FEBS Lett 2009; 583:1215-25. [PMID: 19324042 DOI: 10.1016/j.febslet.2009.03.038] [Citation(s) in RCA: 115] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2008] [Revised: 02/20/2009] [Accepted: 03/02/2009] [Indexed: 12/23/2022]
Abstract
An association between hyperlipidemia and hyperhomocysteinemia (HHCY) has been suggested. This link is clinically important in management of vascular risk factors especially in elderly people and patients with metabolic syndrome. Higher plasma homocysteine (Hcy) was associated with lower high-density lipoprotein (HDL)-cholesterol level. Moreover, HHCY was associated with disturbed plasma lipids or fatty liver. It seems that hypomethylation associated with HHCY is responsible for lipid accumulation in tissues. Decreased methyl group will decrease the synthesis of phosphatidylcholine, a major phospholipid required for very low-density lipoprotein (VLDL) assembly and homeostasis. The effect of Hcy on HDL-cholesterol is probably related to inhibiting enzymes or molecules participating in HDL-particle assembly.
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Affiliation(s)
- Rima Obeid
- Department of Clinical Chemistry and Laboratory Medicine, Central Laboratory, University Hospital, Saarland University, D-66424 Homburg/Saar, Germany
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Hoffman JR, Ratamess NA, Kang J, Rashti SL, Faigenbaum AD. Effect of betaine supplementation on power performance and fatigue. J Int Soc Sports Nutr 2009; 6:7. [PMID: 19250531 PMCID: PMC2651845 DOI: 10.1186/1550-2783-6-7] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2009] [Accepted: 02/27/2009] [Indexed: 12/16/2022] Open
Abstract
Background The purpose of this study was to examine the efficacy of 15 days of betaine supplementation on muscle endurance, power performance and rate of fatigue in active college-aged men. Methods Twenty-four male subjects were randomly assigned to one of two groups. The first group (BET; 20.4 ± 1.3 years; height: 176.8 ± 6.6 cm; body mass: 77.8 ± 13.4 kg) consumed the supplement daily, and the second group (PL; 21.4 ± 4.7 years; height: 181.3 ± 5.9 cm; body mass: 83.3 ± 5.2 kg) consumed a placebo. Subjects were tested prior to the onset of supplementation (T1) and 7 (T2) and 14 days (T3) following supplementation. Each testing period occurred over a 2-day period. During day one of testing subjects performed a vertical jump power (VJP) and a bench press throw (BPT) power test. In addition, subjects were required to perform as many repetitions as possible with 75% of their 1-RM in both the squat and bench press exercises. Both peak and mean power was assessed on each repetition. On day two of testing subjects performed two 30-sec Wingate anaerobic power tests (WAnT), each test separated by a 5-min active rest. Results No differences were seen at T2 or T3 in the repetitions performed to exhaustion or in the number of repetitions performed at 90% of both peak and mean power between the groups in the bench press exercise. The number of repetitions performed in the squat exercise for BET was significantly greater (p < 0.05) than that seen for PL at T2. The number of repetitions performed at 90% or greater of peak power in the squat exercise was significantly greater for BET at both T2 and T3 than PL. No differences in any power assessment (VJP, BPT, WAnT) was seen between the groups Conclusion Two-weeks of betaine supplementation in active, college males appeared to improve muscle endurance of the squat exercise, and increase the quality of repetitions performed.
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Affiliation(s)
- Jay R Hoffman
- Department of Health and Exercise Science, The College of New Jersey, PO Box 7718, Ewing, New Jersey 08628, USA.
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