1
|
Leclerc D, Christensen KE, Reagan AM, Keser V, Luan Y, Malysheva OV, Wasek B, Bottiglieri T, Caudill MA, Howell GR, Rozen R. Folate Deficiency and/or the Genetic Variant Mthfr 677C >T Can Drive Hepatic Fibrosis or Steatosis in Mice, in a Sex-Specific Manner. Mol Nutr Food Res 2024; 68:e2300355. [PMID: 38327171 DOI: 10.1002/mnfr.202300355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 11/24/2023] [Indexed: 02/09/2024]
Abstract
SCOPE Disturbances in one-carbon metabolism contribute to nonalcoholic fatty liver disease (NAFLD) which encompasses steatosis, steatohepatitis, fibrosis, and cirrhosis. The goal is to examine impact of folate deficiency and the Mthfr677C >T variant on NAFLD. METHODS AND RESULTS This study uses the new Mthfr677C >T mouse model for the human MTHFR677C >T variant. Mthfr677CC and Mthfr677TT mice were fed control diet (CD) or folate-deficient (FD) diets for 4 months. FD and Mthfr677TT alter choline/methyl metabolites in liver and/or plasma (decreased S-adenosylmethionine (SAM):S-adenosylhomocysteine (SAH) ratio, methyltetrahydrofolate, and betaine; increased homocysteine [Hcy]). FD, with contribution from Mthfr677TT, provokes fibrosis in males. Studies of normal livers reveal alterations in plasma markers and gene expression that suggest an underlying predisposition to fibrosis induced by FD and/or Mthfr677TT in males. These changes are absent or reverse in females, consistent with the sex disparity of fibrosis. Sex-based differences in methylation potential, betaine, sphingomyelin, and trimethylamine-N-oxide (TMAO) levels may prevent fibrogenesis in females. In contrast, Mthfr677TT alters choline metabolism, dysregulates expression of lipid metabolism genes, and promotes steatosis in females. CONCLUSION This study suggests that folate deficiency predisposes males to fibrosis, which is exacerbated by Mthfr677TT, whereas Mthfr677TT predisposes females to steatosis, and reveal novel contributory mechanisms for these NAFLD-related disorders.
Collapse
Affiliation(s)
- Daniel Leclerc
- Departments of Human Genetics and Pediatrics, McGill University, Research Institute of the McGill University Health Center, Montreal, Quebec, Canada
| | - Karen E Christensen
- Departments of Human Genetics and Pediatrics, McGill University, Research Institute of the McGill University Health Center, Montreal, Quebec, Canada
| | | | - Vafa Keser
- Departments of Human Genetics and Pediatrics, McGill University, Research Institute of the McGill University Health Center, Montreal, Quebec, Canada
| | - Yan Luan
- Departments of Human Genetics and Pediatrics, McGill University, Research Institute of the McGill University Health Center, Montreal, Quebec, Canada
| | - Olga V Malysheva
- Division of Nutritional Sciences and Genomics, Cornell University, Ithaca, NY, USA
| | - Brandi Wasek
- Center of Metabolomics, Institute of Metabolic Disease, Baylor Scott & White Research Institute, Dallas, TX, USA
| | - Teodoro Bottiglieri
- Center of Metabolomics, Institute of Metabolic Disease, Baylor Scott & White Research Institute, Dallas, TX, USA
| | - Marie A Caudill
- Division of Nutritional Sciences and Genomics, Cornell University, Ithaca, NY, USA
| | | | - Rima Rozen
- Departments of Human Genetics and Pediatrics, McGill University, Research Institute of the McGill University Health Center, Montreal, Quebec, Canada
| |
Collapse
|
2
|
Zhang B, Wang Y, Niu K, Liu Z, Zheng Y. [Efficient synthesis of L-methionine by engineering the one carbon module of Escherichia coli]. Sheng Wu Gong Cheng Xue Bao 2023; 39:3302-3317. [PMID: 37622362 DOI: 10.13345/j.cjb.230138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 08/26/2023]
Abstract
L-methionine, also known as L-aminomethane, is one of the eight essential amino acids required by the human body and has important applications in the fields of feed, medicine, and food. In this study, an L-methionine high-yielding strain was constructed using a modular metabolic engineering strategy based on the M2 strain (Escherichia coli W3110 ΔIJAHFEBC/PAM) previously constructed in our laboratory. Firstly, the production of one-carbon module methyl donors was enhanced by overexpression of methylenetetrahydrofolate reductase (methylenetetrahydrofolate reductase, MetF) and screening of hydroxymethyltransferase (GlyA) from different sources, optimizing the one-carbon module. Subsequently, cysteamine lyase (hydroxymethyltransferase, MalY) and cysteine internal transporter gene (fliY) were overexpressed to improve the supply of L-homocysteine and L-cysteine, two precursors of the one-carbon module. The production of L-methionine in shake flask fermentation was increased from 2.8 g/L to 4.05 g/L, and up to 18.26 g/L in a 5 L fermenter. The results indicate that the one carbon module has a significant impact on the biosynthesis of L-methionine, and efficient biosynthesis of L-methionine can be achieved through optimizing the one carbon module. This study may facilitate further improvement of microbial fermentation production of L-methionine.
Collapse
Affiliation(s)
- Bo Zhang
- The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou 310014, Zhejiang, China
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310014, Zhejiang, China
| | - Ying Wang
- The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou 310014, Zhejiang, China
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310014, Zhejiang, China
| | - Kun Niu
- The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou 310014, Zhejiang, China
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310014, Zhejiang, China
| | - Zhiqiang Liu
- The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou 310014, Zhejiang, China
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310014, Zhejiang, China
| | - Yuguo Zheng
- The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou 310014, Zhejiang, China
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310014, Zhejiang, China
| |
Collapse
|
3
|
Naseem A, Pal A, Gowan S, Asad Y, Donovan A, Temesszentandrási-Ambrus C, Kis E, Gaborik Z, Bhalay G, Raynaud F. Intracellular Metabolomics Identifies Efflux Transporter Inhibitors in a Routine Caco-2 Cell Permeability Assay-Biological Implications. Cells 2022; 11:3286. [PMID: 36291153 PMCID: PMC9601193 DOI: 10.3390/cells11203286] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 10/14/2022] [Accepted: 10/17/2022] [Indexed: 12/05/2023] Open
Abstract
Caco-2 screens are routinely used in laboratories to measure the permeability of compounds and can identify substrates of efflux transporters. In this study, we hypothesized that efflux transporter inhibition of a compound can be predicted by an intracellular metabolic signature in Caco-2 cells in the assay used to test intestinal permeability. Using selective inhibitors and transporter knock-out (KO) cells and a targeted Liquid Chromatography tandem Mass Spectrometry (LC-MS) method, we identified 11 metabolites increased in cells with depleted P-glycoprotein (Pgp) activity. Four metabolites were altered with Breast Cancer Resistance (BCRP) inhibition and nine metabolites were identified in the Multidrug Drug Resistance Protein 2 (MRP2) signature. A scoring system was created that could discriminate among the three transporters and validated with additional inhibitors. Pgp and MRP2 substrates did not score as inhibitors. In contrast, BCRP substrates and inhibitors showed a similar intracellular metabolomic signature. Network analysis of signature metabolites led us to investigate changes of enzymes in one-carbon metabolism (folate and methionine cycles). Our data shows that methylenetetrahydrofolate reductase (MTHFR) protein levels increased with Pgp inhibition and Thymidylate synthase (TS) protein levels were reduced with Pgp and MRP2 inhibition. In addition, the methionine cycle is also affected by both Pgp and MRP2 inhibition. In summary, we demonstrated that the routine Caco-2 assay has the potential to identify efflux transporter inhibitors in parallel with substrates in the assays currently used in many DMPK laboratories and that inhibition of efflux transporters has biological consequences.
Collapse
Affiliation(s)
- Afia Naseem
- Division of Cancer Therapeutics, The Institute of Cancer Research, 15 Cotswold Rd., Sutton SM2 5NG, UK
| | - Akos Pal
- Division of Cancer Therapeutics, The Institute of Cancer Research, 15 Cotswold Rd., Sutton SM2 5NG, UK
| | - Sharon Gowan
- Division of Cancer Therapeutics, The Institute of Cancer Research, 15 Cotswold Rd., Sutton SM2 5NG, UK
| | - Yasmin Asad
- Division of Cancer Therapeutics, The Institute of Cancer Research, 15 Cotswold Rd., Sutton SM2 5NG, UK
| | - Adam Donovan
- Division of Cancer Therapeutics, The Institute of Cancer Research, 15 Cotswold Rd., Sutton SM2 5NG, UK
| | | | - Emese Kis
- SOLVO Biotechnology, Charles River Company, Irinyi József u. 4-20, 1117 Budapest, Hungary
| | - Zsuzsanna Gaborik
- SOLVO Biotechnology, Charles River Company, Irinyi József u. 4-20, 1117 Budapest, Hungary
| | - Gurdip Bhalay
- Division of Cancer Therapeutics, The Institute of Cancer Research, 15 Cotswold Rd., Sutton SM2 5NG, UK
| | - Florence Raynaud
- Division of Cancer Therapeutics, The Institute of Cancer Research, 15 Cotswold Rd., Sutton SM2 5NG, UK
| |
Collapse
|
4
|
Sedlak L, Świerczyńska M, Pojda-Wilczek D. Combined central retinal vein and cilioretinal artery occlusion in a 25-year-old woman. Rom J Ophthalmol 2022; 66:178-184. [PMID: 35935085 PMCID: PMC9289772 DOI: 10.22336/rjo.2022.35] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/19/2022] [Indexed: 11/23/2022] Open
Abstract
We report a case of a 25-year-old woman with sudden and painless diminution in vision and central scotoma in her left eye (LE). She was a smoker and had been taking combined oral contraceptive (COC) pills for 1 year. On admission, the best-corrected visual acuity (BCVA) was 1,5/50 in the LE. Posterior segment examination revealed optic disc edema with flame-shaped retinal hemorrhages, mildly tortuous and dilated retinal veins. Moreover, retinal edema in the peripapillary and perimacular region, foci of hemorrhages and Roth’s spots in the posterior pole, as well as pale superior papillomacular bundle were observed. Fundus fluorescein angiography (FFA) confirmed the delayed flow of contrast through the cilioretinal artery in the LE. The clinical picture suggested left central retinal vein (CRVO) with cilioretinal artery occlusion (CLRAO). All laboratory and imaging tests were normal except for homozygous methylenetetrahydrofolate reductase (MTHFR) gene mutation (A1298C genotypes). However, serum homocysteine (Hcy) level was normal. Low molecular weight heparin (LMWH) treatment was administered. Retinal lesions, as well as BCVA improved, but central scotoma remained. Abbreviations: aPTT = activated partial thromboplastin time, BCVA = best-corrected visual acuity, CBC = complete blood count, CLRAO = cilioretinal artery occlusion, COC = combined oral contraceptive, CRA = central retinal artery, CRP = serum C-reactive protein, CRVO = central retinal vein occlusion, CT = computed tomography, CTA = computed tomography angiography, ECG = electrocardiography, ESR = erythrocyte sedimentation rate, FERG = flash electroretinogram, FFA = fundus fluorescein angiography, GCA = ganglion cell analysis, GCL = ganglion cell layer, Hcy = homocysteine, ICGA = indocyanine green angiography, INR = international normalized ratio, IOP = intraocular pressure, IPL = inner plexiform layer, LE = left eye, LMWH = low molecular weight heparin, mfERG = multifocal electroretinogram, MTHFR = methylenetetrahydrofolate reductase, OCT = optical coherence tomography, RE = right eye, VF = visual field
Collapse
Affiliation(s)
- Lech Sedlak
- Department of Ophthalmology, Faculty of Medical Sciences in Katowice, Medical University of Silesia, Katowice, Poland
- Department of Ophthalmology, Kornel Gibiński University Clinical Center, Medical University of Silesia, Katowice, Poland
| | - Marta Świerczyńska
- Department of Ophthalmology, Faculty of Medical Sciences in Katowice, Medical University of Silesia, Katowice, Poland
- Department of Ophthalmology, Kornel Gibiński University Clinical Center, Medical University of Silesia, Katowice, Poland
| | - Dorota Pojda-Wilczek
- Department of Ophthalmology, Faculty of Medical Sciences in Katowice, Medical University of Silesia, Katowice, Poland
- Department of Ophthalmology, Kornel Gibiński University Clinical Center, Medical University of Silesia, Katowice, Poland
| |
Collapse
|
5
|
De Martinis M, Sirufo MM, Nocelli C, Fontanella L, Ginaldi L. Hyperhomocysteinemia is Associated with Inflammation, Bone Resorption, Vitamin B12 and Folate Deficiency and MTHFR C677T Polymorphism in Postmenopausal Women with Decreased Bone Mineral Density. Int J Environ Res Public Health 2020; 17:E4260. [PMID: 32549258 PMCID: PMC7345373 DOI: 10.3390/ijerph17124260] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 06/10/2020] [Accepted: 06/12/2020] [Indexed: 12/15/2022]
Abstract
Osteoporosis is an age-related bone disease, affecting mainly postmenopausal women, characterized by decreased bone mineral density (BMD) and consequent risk of fractures. Homocysteine (Hcy), a sulfur-aminoacid whose serum level is regulated by methylenetrahydrofolate reductase (MTHFR) activity and vitamin B12 and folate as cofactors, is a risk factor for inflammatory diseases. Literature data concerning the link between Hcy and osteoporosis are still debated. The aim of our study was to assess the relationship among Hcy and BMD, inflammation, vitamin status and bone turnover in postmenopausal osteoporosis. In 252 postmenopausal women, BMD was measured by dual-energy X-ray absorptiometry (DXA). In addition to serum Hcy, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and bone turnover markers (bone alkaline phosphatase-BAP, osteocalcin-OC, C-terminal telopeptide of type I collagen (CTX), vitamin deficiencies and MTHFR-C677T polymorphism were evaluated. Hcy, inflammation, bone resorption markers and prevalence of C677T polymorphism were higher, whereas vitamin D, B12, folate, and bone formation markers were lower in women with decreased BMD compared to those with normal BMD. Our results suggest a significant association between Hcy, BMD and inflammation in postmenopausal osteoporosis. The regulation of Hcy overproduction and the modulation of the inflammatory substrate could represent additional therapeutic approaches for osteoporosis prevention.
Collapse
Affiliation(s)
- Massimo De Martinis
- Department of Life, Health and Environmental Sciences, University of L’Aquila, 67100 L’Aquila, Italy; (M.M.S.); (L.G.)
- Allergy and Clinical Immunology Unit, Center for the diagnosis and treatment of Osteoporosis, AUSL 04, 64100 Teramo, Italy
| | - Maria Maddalena Sirufo
- Department of Life, Health and Environmental Sciences, University of L’Aquila, 67100 L’Aquila, Italy; (M.M.S.); (L.G.)
- Allergy and Clinical Immunology Unit, Center for the diagnosis and treatment of Osteoporosis, AUSL 04, 64100 Teramo, Italy
| | | | - Lara Fontanella
- Department of Legal and Social Sciences, University of Chieti-Pescara, 65127 Pescara, Italy;
| | - Lia Ginaldi
- Department of Life, Health and Environmental Sciences, University of L’Aquila, 67100 L’Aquila, Italy; (M.M.S.); (L.G.)
- Allergy and Clinical Immunology Unit, Center for the diagnosis and treatment of Osteoporosis, AUSL 04, 64100 Teramo, Italy
| |
Collapse
|
6
|
Stoccoro A, Tannorella P, Migliore L, Coppedè F. Polymorphisms of genes required for methionine synthesis and DNA methylation influence mitochondrial DNA methylation. Epigenomics 2020; 12:1003-1012. [PMID: 32393056 DOI: 10.2217/epi-2020-0041] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Aim: Impaired methylation of the mitochondrial DNA and particularly in the regulatory displacement loop (D-loop) region, is increasingly observed in patients with neurodegenerative disorders. The present study aims to investigate if common polymorphisms of genes required for one-carbon metabolism (MTHFR, MTRR, MTR and RFC-1) and DNA methylation reactions (DNMT1, DNMT3A and DNMT3B) influence D-loop methylation levels. Materials & methods: D-loop methylation data were available from 133 late-onset Alzheimer's disease patients and 130 matched controls. Genotyping was performed with PCR-RFLP or high resolution melting techniques. Results: Both MTRR 66A > G and DNMT3A -448A > G polymorphisms were significantly associated with D-loop methylation levels. Conclusion: This exploratory study suggests that MTRR and DNMT3A polymorphisms influence mitochondrial DNA methylation; further research is required to better address this issue.
Collapse
Affiliation(s)
- Andrea Stoccoro
- Department of Translational Research & of New Surgical & Medical Technologies, University of Pisa, Via Roma 55, 56126, Pisa, Italy
| | - Pierpaola Tannorella
- Department of Translational Research & of New Surgical & Medical Technologies, University of Pisa, Via Roma 55, 56126, Pisa, Italy
- Current address: Unit of Genetics of Neurodegenerative & Metabolic Diseases, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Lucia Migliore
- Department of Translational Research & of New Surgical & Medical Technologies, University of Pisa, Via Roma 55, 56126, Pisa, Italy
| | - Fabio Coppedè
- Department of Translational Research & of New Surgical & Medical Technologies, University of Pisa, Via Roma 55, 56126, Pisa, Italy
| |
Collapse
|
7
|
Qiao K, Zhang S, Trieu C, Dai Q, Huo Z, Du Y, Lu W, Hou W. Genetic Polymorphism of MTHFR C677T Influences Susceptibility to HBV-Related Hepatocellular Carcinoma in a Chinese Population: a Case-Control Study. Clin Lab 2017; 63:787-795. [PMID: 28397480 DOI: 10.7754/clin.lab.2016.161003] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
BACKGROUND Methylene tetrahydrofolate reductase (MTHFR) is the key enzyme of folic acid metabolism and the C677T mutation is associated with decreased enzyme activity. Several studies have shown its regulatory role in carcinogenesis and tumor growth. HBV (hepatitis B virus)-related HCC (hepatocellular carcinoma) is one of the most common liver cancers worldwide. Therefore, the present case-control study aimed to investigate the role of genetic polymorphism of MTHFR C677T in the development and progression of HBV-related HCC in a Chinese population. METHODS Subjects enrolled included 204 HBV-related HCC patients and 211 HBV infected patients without HCC. MTHFR C677T polymorphism was genotyped via a DNA microarray-based assay. The relationship between the MTHFR C677T polymorphism and HBV-related HCC was analyzed. RESULTS The genotype frequencies of MTHFR C677T were statistically different between the HCC and control groups (p = 0.025). The TT genotype was associated with elevated risk of HBV-related HCC in a Chinese population under different genetic models after an adjustment for age, gender, HBV infection duration, and HCC family history (T vs. C, OR = 1.462, 95% CI: 1.090 - 1.962, p = 0.011; TT vs. CC, OR = 2.151, 95% CI: 1.143 - 4.049, p = 0.018; TT vs. CC+CT, OR = 1.918, 95% CI: 1.215 - 3.026, p = 0.005). When stratified with the known duration of HBV infection, subjects with HBV infection duration of more than 20 years and carrying the homozygous TT genotype had a higher susceptibility to HCC than those with the C allele (CC/CT) (OR = 2.568, 95% CI: 1.244 - 5.303; p = 0.011). There was no significant association between MTHFR C677T genotypes and HCC stages based on BCLC staging system. CONCLUSIONS MTHFR C677T polymorphism with TT genotype could be a factor that increases the risk of HBVrelated HCC in a Chinese population, especially those with HBV infection duration of more than 20 years.
Collapse
|
8
|
Li WX, Cheng F, Zhang AJ, Dai SX, Li GH, Lv WW, Zhou T, Zhang Q, Zhang H, Zhang T, Liu F, Liu D, Huang JF. Folate Deficiency and Gene Polymorphisms of MTHFR, MTR and MTRR Elevate the Hyperhomocysteinemia Risk. Clin Lab 2017; 63:523-533. [PMID: 28271696 DOI: 10.7754/clin.lab.2016.160917] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
BACKGROUND Hyperhomocysteinemia (HHcy) is an independent risk factor for cardiovascular diseases (CVDs). We aimed to investigate the joint effect of homocysteine metabolism gene polymorphisms, as well as the folate deficiency on the risk of HHcy in a Chinese hypertensive population. METHODS This study enrolled 480 hypertensive patients aged 28 - 75 from six hospitals in different Chinese regions from 9/2005 - 12/2005. Known genotypes of methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C, methionine synthase (MTR) A2756G, and methionine synthase reductase (MTRR) A66G were detected by PCRRFLP methods. Serum Hcy was measured by high-performance liquid chromatography and serum folate was measured by chemiluminescent immunoassay. RESULTS MTHFR C677T and MTR A2756G can independently elevate the risk of HHcy (TT vs. CC + CT, p < 0.001 and AG + GG vs. AA, p = 0.026, respectively), whereas MTHFR A1298C decreased HHcy risk (AC + CC vs. AA, p < 0.001) and showed a protective effect against HHcy risk. Importantly, the joint effect of these risk genotypes showed significantly higher odds of HHcy than non-risk genotypes, especially the patients with four risk genotypes. It is noteworthy that this deleterious effect was aggravated by folate deficiency. These findings were verified by generalized multifactor dimensionality reduction model (p = 0.001) and a cumulative effects model (p < 0.001). CONCLUSIONS We have first demonstrated that the joint effect of homocysteine metabolism gene polymorphisms and folate deficiency lead to dramatic elevations in the HHcy risk.
Collapse
|
9
|
Lall N, Kumar V, Meyer D, Gasa N, Hamilton C, Matsabisa M, Oosthuizen C. In vitro and In vivo antimycobacterial, hepatoprotective and immunomodulatory activity of Euclea natalensis and its mode of action. J Ethnopharmacol 2016; 194:740-748. [PMID: 27773800 DOI: 10.1016/j.jep.2016.10.060] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Revised: 10/11/2016] [Accepted: 10/19/2016] [Indexed: 06/06/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE The Natal gwarri or Natal ebony (Euclea natalensis A.DC.) is a deciduous tree found widespread throughout southern Africa, especially in Kwazulu-Natal and the southern cost. It has been widely used by indigenous communities such as the Zulus, Tsongas and Vendas for symptoms related to tuberculosis (TB). The decoctions made from the plant parts are administered for chest diseases to treat complications such as chest pains, bronchitis, pleurisy and asthma. TB is prevalent in immune-compromised patients and it is evident that TB-drugs cause hepatotoxicity. The objective of the present study was therefore to evaluate the antimycobacterial activity of the ethanolic extract of E. natalensis against TB and its hepatoprotective and immunomodulatory activities. MATERIALS AND METHODS The antimycobacterial, antioxidant, hepatoprotective, immunomodulatory activity and cytotoxicity of the ethanolic extract of the shoots of E. natalensis were determined in vitro. The mechanism of action of the antituberculosis activity was determined by investigating the inhibitory effect on mycothiol disulfide reductase enzyme. Furthermore, the acute, sub-acute toxicity (50-2000mg/kg) and antimycobacterial effect (300mg/kg) of E. natalensis shoot extract were investigated in Balb/c mice. Hepatoprotective activity of the extract (50-150mg/kg) was evaluated on isoniazid and rifampicin (50mg/kg; i.p.) induced hepatic damage in a rat model. RESULTS The minimum inhibitory concentration of the extract was found to be 125µg/ml against Mycobacterium tuberculosis. The extracts 50% inhibitory concentration (IC50) against 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical was found to be 22.55µg/ml. The plant showed a hepatoprotective effect (50% at 12.5µg/ml) and the ability to increase T-helper 1 cell cytokines; Interleukin 12, Interleukin 2 and Interferon α by up to 12 fold and the ability to decrease the T-helper 2 cell cytokine Interleukin 10 4 fold when compared to baseline cytokine production. No cellular toxicity was observed in primary peripheral blood mononuclear cells (PBMC's) and two secondary cell lines; U937 monocytes and Chang liver cells (a derivative of the HepG2 cell line). During mechanistic studies, the extract showed a 50% inhibition of mycothiol reductase activity at 38.62µg/ml. During the acute and sub-acute studies, E. natalensis exhibited no toxic effect and the 50% lethal dose (LD50) was established to be above 2000mg/kg. The extract was able to reduce the mycobacterial load (1.5-fold reduction) in infected mice. Isoniazid and rifampicin caused significant hepatic damage in rats, and the extract was able to reduce the toxicity by 15% and 40% at 50 and 150mg/kg respectively. CONCLUSION The present study supports the traditional usage of the plant against tuberculosis symptoms. The study showed the ability of E. natalensis shoot extract to inhibit mycobacterial growth, stimulate an appropriate immune response and have a hepatic protective effect. Due to the extract's significant results for hepatoprotective, immunomodulatory effects and antimycobacterial activity, it may prove to be effective to serve as an adjuvant for TB-patients.
Collapse
Affiliation(s)
- Namrita Lall
- Department of Plant and Soil Sciences, University of Pretoria, South Africa.
| | - Vivek Kumar
- Department of Plant and Soil Sciences, University of Pretoria, South Africa.
| | - Debra Meyer
- Department of Plant and Soil Sciences, University of Pretoria, South Africa; Faculty of Science, University of Johannesburg, South Africa.
| | - Nomasomi Gasa
- Department of Plant and Soil Sciences, University of Pretoria, South Africa.
| | - Chris Hamilton
- Department of Plant and Soil Sciences, University of Pretoria, South Africa; Department of Pharmacy, University of East Anglia, Norwich, United kingdom.
| | | | - Carel Oosthuizen
- Department of Plant and Soil Sciences, University of Pretoria, South Africa.
| |
Collapse
|
10
|
Türedi Yildirim A, Sütçü R, Köroğlu M, Delibaş N, Kişioğlu N, Akar N, Ergürhan İlha I. The role of prothrombotic factors in children with hemiplegic cerebral palsy. Minerva Pediatr 2015; 67:279-284. [PMID: 25034217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
AIM Hemiplegic cerebral palsy (HCP) is a condition occurring as a consequence of a non-progressive damage of the brain with incomplete anatomical and physical development during the early period of life. Its etiology is multifactorial, with the cause remaining unexplained in the majority of cases. This study aims to investigate whether thrombophilic factors correlates with the etiology in children with HCP. METHODS We included 36 children with HCP in the patient group, and 41 healthy children with no neurologic disorders in the control group. No significant difference was found between the two groups in terms of factor V leiden, methylenetetrahydrofolate reductase and prothrombin 20210A mutation frequency and protein C, protein S and antithrombin III levels. RESULTS Homocysteine levels were significantly higher in the group of patients with HCP as compared to the control group (P=0.012). Because we could not identify the origin of hyperhomocysteinemia as congenital or acquired, the impact of hyperhomocysteinemia on HCP was considered insignificant. Each thrombophilic disorder was assessed in terms of relatedness to atrophy, periventricular leukomalacia, infarct, congenital anomaly and porencephalic cyst, respectively. No significant correlation was detected between thrombophilic disorders and cranial imaging findings. CONCLUSION Our study has shown that thrombophilic factors are not involved in the etiology of HCP.
Collapse
Affiliation(s)
- A Türedi Yildirim
- Department of Pediatric Hematology, School of Medicine, Celal Bayar University, Manisa, Turkey -
| | | | | | | | | | | | | |
Collapse
|
11
|
Xiao WL, Shi B, Wang Y, Zheng Q, Huang L. [Gene expression of methylene tetrahydrofolate reductase and its silencing effect in primary culture mouse embryo palatal mesenchymal cell]. Hua Xi Kou Qiang Yi Xue Za Zhi 2009; 27:244-247. [PMID: 19637468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
OBJECTIVE To construct a small interfering RNA (siRNA) eukaryotic expression vector specific for methylene tetrahydrofolate reductase (MTHFR) gene and to observe its silencing effect on MTHFR gene. METHODS The expression vectors of PsiRNA-MTHFR were constructed by gene recombination and then were nucleofected into the primary cultured MEPM cell. At 48 h and 5 d after nucleofection, the expression of MTHFR in the levels of mRNA and protein was detected by real-time quantitative polymerase chain reaction (Real-Time PCR) and Western blot. RESULTS The eukaryotic expression vector of PsiRNA-MTHFR, which significantly down-regulated mRNA and protein of MTHFR at 48 h and 5 d after nucleofection, were successfully constructed. CONCLUSION Eukaryotic expression vector of siRNA specific for MTHFR is successfully contructed, which lays the basis for its application in the mechanism research of MTHFR gene regulating embryo palate shelves fusion.
Collapse
Affiliation(s)
- Wen-Lin Xiao
- Dept. of Oral and Maxillofacial Surgery, The Medical School Hospital of Qingdao University, Qingdao 266003, China
| | | | | | | | | |
Collapse
|
12
|
Pejchal R, Campbell E, Guenther BD, Lennon BW, Matthews RG, Ludwig ML. Structural perturbations in the Ala --> Val polymorphism of methylenetetrahydrofolate reductase: how binding of folates may protect against inactivation. Biochemistry 2006; 45:4808-18. [PMID: 16605249 PMCID: PMC1868400 DOI: 10.1021/bi052294c] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In human methylenetetrahydrofolate reductase (MTHFR) the Ala222Val (677C-->T) polymorphism encodes a heat-labile gene product that is associated with elevated levels of homocysteine and possibly with risk for cardiovascular disease. Generation of the equivalent Ala to Val mutation in Escherichia coli MTHFR, which is 30% identical to the catalytic domain of the human enzyme, creates a protein with enhanced thermolability. In both human and E. coli MTHFR, the A --> V mutation increases the rate of dissociation of FAD, and in both enzymes, loss of FAD is linked to changes in quaternary structure [Yamada, K., Chen, Z., Rozen, R., and Matthews, R. G. (2001) Proc. Natl. Acad. Sci. U.S.A. 98, 14853-14858; Guenther, B. D., Sheppard, C. A., Tran, P., Rozen, R., Matthews, R. G., and Ludwig, M. L. (1999) Nat. Struct. Biol. 6, 359-365]. Folates have been shown to protect both human and bacterial enzymes from loss of FAD. Despite its effect on affinity for FAD, the A --> V mutation is located at the bottom of the (betaalpha)(8) barrel of the catalytic domain in a position that does not contact the bound FAD prosthetic group. Here we report the structures of the Ala177Val mutant of E. coli MTHFR and of its complex with the 5,10-dideazafolate analogue, LY309887, and suggest mechanisms by which the mutation may perturb FAD binding. Helix alpha5, which immediately precedes the loop bearing the mutation, carries several residues that interact with FAD, including Asn168, Arg171, and Lys172. In the structures of the mutant enzyme this helix is displaced, perturbing protein-FAD interactions. In the complex with LY309887, the pterin-like ring of the analogue stacks against the si face of the flavin and is secured by hydrogen bonds to residues Gln183 and Asp120 that adjoin this face. The direct interactions of bound folate with the cofactor provide one mechanism for linkage between binding of FAD and folate binding that could account in part for the protective action of folates. Conformation changes induced by folate binding may also suppress dissociation of FAD.
Collapse
Affiliation(s)
- Robert Pejchal
- Department of Biological Chemistry, the Biophysics Research Division, and the Life Sciences Institute, The University of Michigan, Ann Arbor, Michigan 48109
| | | | | | | | - Rowena G. Matthews
- Department of Biological Chemistry, the Biophysics Research Division, and the Life Sciences Institute, The University of Michigan, Ann Arbor, Michigan 48109
| | - Martha L. Ludwig
- Department of Biological Chemistry, the Biophysics Research Division, and the Life Sciences Institute, The University of Michigan, Ann Arbor, Michigan 48109
| |
Collapse
|
13
|
Shimasaki N, Mori T, Samejima H, Sato R, Shimada H, Yahagi N, Torii C, Yoshihara H, Tanigawara Y, Takahashi T, Kosaki K. Effects of methylenetetrahydrofolate reductase and reduced folate carrier 1 polymorphisms on high-dose methotrexate-induced toxicities in children with acute lymphoblastic leukemia or lymphoma. J Pediatr Hematol Oncol 2006; 28:64-8. [PMID: 16462575 DOI: 10.1097/01.mph.0000198269.61948.90] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The authors investigated whether high-dose methotrexate-induced toxicity differed according to the presence of methylenetetrahydrofolate reductase (MTHFR) or reduced folate carrier 1 (RFC1) genetic polymorphism. The authors studied 15 children with acute lymphoblastic leukemia or lymphoblastic lymphoma who were treated using protocols that included high-dose methotrexate (3.0 g/m), for an overall total of 43 courses. Methotrexate-induced toxicities and the plasma methotrexate concentrations were evaluated retrospectively. Hematologic toxicity was the most frequently observed toxicity, appearing in 87% of the patients. In a subset of patients (47%), elevation of liver transaminase levels showed a repeated tendency to develop. High plasma methotrexate concentrations at 48 hours after the methotrexate infusion were not significantly related to methotrexate-induced toxicities except for mucositis. A generalized estimating equation analysis revealed that vomiting during the high-dose methotrexate treatment was more pronounced in patients who had a larger number of G alleles at the RFC1 80G>A polymorphism. No significant differences in the development of other toxicities or in the plasma methotrexate concentrations were observed for the different MTHFR 677C>T or RFC1 80G>A polymorphisms. This study suggests but does not prove that the RFC1 80G>A polymorphism may contribute to interindividual variability in responses to high-dose methotrexate.
Collapse
Affiliation(s)
- Noriko Shimasaki
- Department of Pediatrics, Keio University School of Medicine, Tokyo, Japan
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
14
|
Park BH, Kim YJ, Park JS, Lee HY, Ha EH, Min JW, Park HS. [Folate and homocysteine levels during pregnancy affect DNA methylation in human placenta]. J Prev Med Public Health 2005; 38:437-42. [PMID: 16358830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/05/2023] Open
Abstract
OBJECTIVES DNA methylation is one of the best characterized epigenetic mechanisms that play a regulatory role in genome programming and imprinting during embryogenesis. In this present study, we investigated the association between DNA methylation in the human placenta and the maternal folate and homocysteine concentrations on the Methylenetetrahydrofolatereductase (MTHFR) genetic polymorphism during pregnancy. METHODS We investigated 107 pregnant women who visited Ewha Woman's University Hospital for prenatal care during their 24-28 weeks-period of gestation. During the second trimester, we measured the serum homocysteine and folate concentrations. The MTHFR 677 genetic polymorphism was determine by performing PCR-RFLP assay. The expression of DNA methylation in the human placentas was estimated by using immunohistochemistry method. RESULTS Serum folate was negatively correlated with the serum homocysteine concentration for all the MTHFR genotypes. We found positive correlation between the folate concentrations and the DNA methylation in the human placenta (p<0.05). An increasing concentration of homocysteine was associated with reduced DNA methylation in the human placenta. The coefficient value was -2.03 (-3.77, -0.29) on the regression model (p<0.05). CONCLUSION These findings suggest that the maternal folate and homocysteine levels along with the MTHFR 677 genetic polymorphism during pregnancy affect the DNA methylation in the human placenta.
Collapse
Affiliation(s)
- Bo-hyun Park
- Department of Preventive Medicine, Ewha Womans University.
| | | | | | | | | | | | | |
Collapse
|
15
|
Pei LJ, Ren AG, Zhu HP, Hao L, Zhao WR, Li Z, Hou GW, Zhang BL, Jiang YY, Wu LM, Pan YJ, Zhang ML. [Study on reduced folate carrier gene (RFC1) polymorphism in the southern and northern Chinese population]. Zhonghua Liu Xing Bing Xue Za Zhi 2004; 25:499-502. [PMID: 15231126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/30/2023]
Abstract
OBJECTIVE To describe the distribution of reduced folate carrier gene (RFC1)genotype and allele frequency between southern and northern, female and male Chinese population. METHOD RFC1 (A80G) genotype was detected, using polymerase chain reaction-restriction fragment length polymorphism (RFLP-PCR) on 720 blood spot DNA from the normal subjects. RESULTS The frequencies of the northern population with AA, GG and GA genotypes were 22.28%, 31.09% and 46.63%, and the frequencies of the southern population were 18.56%, 22.75% and 58.68%, respectively. Findings showed that there were significant differences between southerners and northerners in RFC1 (A80G) genotype (P < 0.01). There was no significant difference between G allele frequency of the northern (52.10%) and southern population (54.40%). The frequencies of male with RFC1 (A80G) AA, GG and GA genotype were 24.88%, 25.85% and 49.27%, and among female were 18.83%, 27.77% and 53.40%, respectively. There were no significant differences between male and female in RFC1 genotype (P > 0.05), or between G allele frequency in female (50.49%) and that in male (54.47%). CONCLUSIONS The distribution of RFC1 genotype seemed to be consistent with neural tube defects (NTDs) while its prevalence among the northerners was higher than that of southerners, with female having a higher NTDs prevalence. This study provided genetic epidemiological data for etiological hypothesis between RFC1 and diseases relative to folate metabolism.
Collapse
Affiliation(s)
- Li-Jun Pei
- Institute of Reproductive and Child Health, National Reference Laboratory on Reproductive Health Research Ministry of Health, Peking University, Beijing 100083, China
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
16
|
Pathare A, al Kindi S, al Belushi T, Bayoumi R, Dennison D, Murlitharan S. Heterozygous methylene tetrahydrofolate reductase mutation with mild hyperhomocysteinemia associated with deep vein thrombosis. Haematologia (Budap) 2003; 32:551-6. [PMID: 12803132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/03/2023]
Abstract
Hyperhomocysteinemia is known to be associated with arterial occlusive vascular disease and venous thrombosis. Here we report a young ethnic Omani patient with recurrent venous thrombosis who was found to be heterozygous for the C677T mutation in the enzyme methyltetrahydrofolate reductase (MTHFR). Moderate hyperhomocysteinemia was also documented in the presence of normal red cell folate and serum B12 levels. No other marker usually associated with hereditary thrombophilia could be demonstrated in the patient, despite extensive investigations on multiple occasions.
Collapse
Affiliation(s)
- Anil Pathare
- Department of Haematology, College of Medicine, Sultan Qaboos University Hospital, Al Khod, P.O. Box 35, Muscat 123, Oman.
| | | | | | | | | | | |
Collapse
|
17
|
Religa D, Styczynska M, Peplonska B, Gabryelewicz T, Pfeffer A, Chodakowska M, Luczywek E, Wasiak B, Stepien K, Golebiowski M, Winblad B, Barcikowska M. Homocysteine, apolipoproteine E and methylenetetrahydrofolate reductase in Alzheimer's disease and mild cognitive impairment. Dement Geriatr Cogn Disord 2003; 16:64-70. [PMID: 12784029 DOI: 10.1159/000070677] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/17/2002] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Alzheimer's disease (AD) is the most common dementia disorder in elderly people. Currently, the only known genetic factor associated with the development of sporadic AD is the apolipoprotein E (ApoE) 4 allele. There is a need to identify other environmental and genetic risk factors that could modulate the risk of developing sporadic AD. OBJECTIVE To analyse the correlation between the ApoE and methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism and plasma homocysteine levels and vitamins (B(12) and folic acid) concentrations in serum from patients with AD and mild cognitive impairment (MCI) as compared with control group. METHODS The study was carried out in 99 AD patients, 98 subjects with MCI and 100 healthy subjects. Diagnosis of probable AD was made according to the NINCDS-ADRDA and DSM-IV criteria. The following factors were analysed: age, gender, duration of disease, concentration of plasma total homocysteine, folic acid and vitamin B(12) in the serum and the polymorphism of MTHRF and ApoE genes. The results obtained were analysed by multivariate analysis of regression. RESULTS We found that plasma total homocysteine is increased in AD patients (p < 0.0001) and depended on the MTHFR T/T genotype in the presence of low folate levels (p < 0.05). The increased frequency of ApoE4 allele in the AD population was independent of homocysteine, folic acid and vitamin B(12) levels and MTHFR status. CONCLUSIONS We conclude that the concentration of plasma total homocysteine is increased in AD patients. This may be associated with the T/T genotype in the MTHFR gene; however, the distribution of the MTHRF C677T polymorphism in the Polish population does not differ in AD and controls.
Collapse
Affiliation(s)
- D Religa
- Department of Neurodegenerative Disorders, Medical Research Centre, Polish Academy of Sciences, Warsaw, Poland.
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
18
|
Kaufman JL. Nitrous oxide and 5,10-methylenetetrahydrofolate reductase. N Engl J Med 2003; 349:1479-80; author reply 1479-80. [PMID: 14535263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 03/16/2023]
|
19
|
|
20
|
Pauer HU, Voigt-Tschirschwitz T, Hinney B, Burfeind P, Wolf C, Emons G, Neesen J. Analyzes of three common thrombophilic gene mutations in German women with recurrent abortions. Acta Obstet Gynecol Scand 2003; 82:942-7. [PMID: 12956845 DOI: 10.1034/j.1600-0412.2003.00293.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
BACKGROUND Several etiological factors have been proposed as a cause for recurrent fetal abortions. Changes in blood coagulation during pregnancy may play an important role in the occurrence of recurrent abortions (RA). METHODS The aim of this study was to investigate the prevalence of factor V Leiden, factor II prothrombin, and methylenetetrahydrofolate reductase (MTHFR) mutations in women with recurrent abortions (> or =2 abortions) in the German population. The mean number of abortions was 3 (range 2-8). RESULTS Frequencies of the factor V Leiden mutation and the prothrombin G20210A mutation were equally high in the patient group compared with our control group (for factor V Leiden: 11/101 vs. 9/122; p-value: 0.348; for prothrombin G20210A: 2/101 vs. 3/122; p-value: 0.81). Moreover, in both the patient and control groups, 15 of the women were homozygous for the MTHFR C677T allele (15/101 vs. 15/122; p-value: 0.635). The occurrence of FV Leiden, FII and MTHFR mutations was not significantly increased in the patient group compared with our control group. CONCLUSION The results of the present study reveal no relationship between these common three thrombophilic mutations and recurrent abortions for the German population, and further studies are essentially recommended on whether a thrombophilia evaluation should be performed in patients with recurrent abortions.
Collapse
Affiliation(s)
- Hans-Ulrich Pauer
- Department of Gynecology and Obstetrics, University of Goettingen, Goettingen, Germany.
| | | | | | | | | | | | | |
Collapse
|
21
|
Abu-Amero KK, Wyngaard CA, Dzimiri N. Prevalence and Role of Methylenetetrahydrofolate Reductase 677 C→T and 1298 A→C Polymorphisms in Coronary Artery Disease in Arabs. Arch Pathol Lab Med 2003; 127:1349-52. [PMID: 14521457 DOI: 10.5858/2003-127-1349-paromr] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Abstract
Context.—Previous studies reported an association of 677 C→T and 1298 A→C methylenetetrahydrofolate reductase (MTHFR) variants with coronary artery disease (CAD). No previous studies concerning the prevalence of these 2 MTHFR variants or their possible association with CAD in Arabs are currently available in the literature.
Objective.—To determine the prevalence of MTHFR variants and their potential relevance to CAD among Arabs.
Design.—We used polymerase chain reaction and restriction enzyme digestion to determine the prevalence of these 2 MTHFR polymorphisms in 625 healthy blood donors (BDs) and 545 angiographically confirmed CAD patients of Arab origin.
Results.—For the 677 C→T variant within the CAD group, 64.2% were homozygous wild-type C/C, 32.1% were heterozygous C/T, and 3.7% were homozygous T/T genotype. Within the BD group tested for the 677 C→T variant, 72.2% were homozygous wild-type C/C, 25.8% were heterozygous C/T, and 2% were homozygous T/T genotype. Within the CAD group tested for the 1298 A→C variant (n = 540), 45.7% were homozygous wild-type A/A, 46.9% were heterozygous A/C, and 7.4% were homozygous C/C genotype. Within the BD group tested for the 1298 A→C variant (n = 625), 39.4% were homozygous wild-type A/A, 51.5% were heterozygous A/C, and 9.1% were homozygous C/C genotype. The distribution and allele frequency of these 2 MTHFR variants followed the Hardy-Weinberg equilibrium and were similar in the CAD and BD study groups. The prevalence of the 677 C→T and 1298 A→C compound heterozygosity was 9.6% for the BD group and 12.3% for the CAD group.
Conclusion.—The 2 MTHFR variants tested in this study, individually or compound, are not associated with CAD. Therefore, neither of these 2 variants can be considered an independent risk factor or a predictor for CAD in this population.
Collapse
Affiliation(s)
- Khaled K Abu-Amero
- Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia.
| | | | | |
Collapse
|
22
|
Pietrzyk JJ, Bik-Multanowski M, Sanak M, Twardowska M. Polymorphisms of the 5,10-methylenetetrahydrofolate and the methionine synthase reductase genes as independent risk factors for spina bifida. J Appl Genet 2003; 44:111-3. [PMID: 12590188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
We analyzed the role of the C677T polymorphism of the 5,10-methylenetetrahydrofolate and the A66G polymorphism of the methionine synthase reductase genes as risk factors for occurrence of spina bifida. The studied population included 106 mothers and 104 children from affected families, and a control group of 100 adults. We found statistically significant differences between the occurrence of the homozygosity in these polymorphisms in the groups of mothers and children with thoracolumbal defects (C677T polymorphism) and lumbosacral defects (A66G polymorphism). We postulate that these polymorphisms should be regarded as independent risk factors for spina bifida.
Collapse
Affiliation(s)
- Jacek J Pietrzyk
- Chair and Department of Pediatrics, Polish-American Children's Hospital, Jagiellonian University, ul. Wielicka 265, 30-663 Kraków, Poland
| | | | | | | |
Collapse
|
23
|
Strauss E, Waliszewski K, Gabriel M, Zapalski S, Pawlak AL. Increased risk of the abdominal aortic aneurysm in carriers of the MTHFR 677T allele. J Appl Genet 2003; 44:85-93. [PMID: 12590185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
Abdominal aortic aneurysm (AAA) presents itself as a progressive dilation of the abdominal aorta, leading--if untreated--to rupture. It is a common disease of the elderly, with a complex etiology. Several genetic, biochemical and environmental factors are recognized as relevant for the pathogenesis of AAA. We determined the polymorphism of the MTHFR (methylenetetrahydrofolate reductase) gene within the fourth exon (C677T) in 63 patients with AAA and compared it to that in 75 subjects of the population sample. The frequencies of the C/C, C/T and T/T genotypes were 65%, 27%, and 8% in the population sample and 33%, 60%, and 6% in the patients. This corresponds to a 4.4-fold greater risk of AAA in subjects who have the 677C/T variant of MTHFR, as compared with those who are 677C/C (p < 0.0001; 95% CI=2.11-9.34). The frequency of allele MTHFR 677T in patients (0.37) was higher than in the population sample (0.21; p < 0.007). This association between the common allele of the MTHFR gene--MTHFR 677T--and the development of AAA suggests that elevated homocysteine (Hcy) may disturb the function of the aortic wall. The disturbance may involve enhancement of elastin degradation, the process enhanced by mild hyperhomocysteinemia in minipigs. The magnitude of this effect, which refers to the AAA patients unselected for familial occurrence, indicates that the disturbance of aortic wall physiology caused by the presence of the MTHFR 677T allele is greater than the effect of the earlier described allele disequilibrium at the polymorphic alleles of the PAI1 (plasminogen activator inhibitor 1) gene seen only in familial cases of AAA.
Collapse
Affiliation(s)
- Ewa Strauss
- Institute of Human Genetics, Polish Academy of Sciences, ul. Strzeszyńska 32, 60-479 Poznań, Poland.
| | | | | | | | | |
Collapse
|
24
|
Li Z, Sun L, Zhang H, Liao Y, Wang D, Zhao B, Zhu Z, Zhao J, Ma A, Han Y, Wang Y, Shi Y, Ye J, Hui R. Elevated plasma homocysteine was associated with hemorrhagic and ischemic stroke, but methylenetetrahydrofolate reductase gene C677T polymorphism was a risk factor for thrombotic stroke: a Multicenter Case-Control Study in China. Stroke 2003; 34:2085-90. [PMID: 12907815 DOI: 10.1161/01.str.0000086753.00555.0d] [Citation(s) in RCA: 149] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE It is still controversial whether elevated plasma homocysteine and the C677T polymorphism of methylenetetrahydrofolate reductase (MTHFR) gene are risk factors for stroke. The aim of the present study was to investigate the association between the 2 factors and stroke in Chinese in a large case-control study. METHODS We recruited 1823 stroke patients (807 cerebral thrombosis, 513 lacunar infarction, 503 intracerebral hemorrhage) and 1832 controls. Total plasma homocysteine was determined by high-performance liquid chromatography. C677T polymorphism was genotyped by polymerase chain reaction and HinfI digestion. RESULTS Total plasma homocysteine levels were significantly higher in cases than controls (median, 14.7 versus 12.8 micromol/L; P<0.001) and associated with an increased risk of 1.87-fold (95% confidence interval [CI], 1.58 to 2.22) for overall stroke, 1.72-fold (95% CI, 1.39 to 2.12) for cerebral thrombosis, 1.89-fold (95% CI, 1.50 to 2.40) for lacunar infarction, and 1.94-fold (95% CI, 1.48 to 2.55) for intracerebral hemorrhage. The C677T mutation of the MTHFR gene was positively correlated with plasma homocysteine levels in both controls (beta=0.250, P<0.001) and cases (beta=0.272, P<0.001) and more frequently in cases than in controls (47.0% versus 44.2%, P=0.017). The TT genotype was associated with an increased risk for overall stroke (odds ratio, 1.27; 95% CI, 1.04 to 1.56) and thrombotic stroke (odds ratio, 1.37; 95% CI, 1.06 to 1.78). CONCLUSIONS The C677T polymorphism of the MTHFR gene was associated with increased risk of cerebral thrombotic stroke in Chinese. Total plasma homocysteine was correlated with both ischemic and hemorrhagic stroke, suggesting potential initiation of homocysteine-lowering therapy in this population.
Collapse
Affiliation(s)
- Zhaohui Li
- Sino-German Laboratory for Molecular Medicine and Center for Molecular Cardiology, Fuwai Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, 167 Beilishilu, Beijing 100037, China
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
25
|
Stöllberger C, Finsterer J. Search for coagulopathy does not obviate search for venous thrombosis in suspected paradoxical embolism. Stroke 2003; 34:e146-7; author reply e146-7. [PMID: 12920257 DOI: 10.1161/01.str.0000087101.18414.d8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
26
|
Abstract
BACKGROUND Moderate hyperhomocysteinemia is considered a risk factor for thrombosis and atherosclerosis. We hypothesized that higher maternal and newborn homocysteine concentrations in plasma would increase the risk of intrauterine growth restriction through placental thrombosis. METHODS We carried out a case-control study that included all cases born at our institution over a 2-year period whose birthweight was below the 10th percentiles for gestational age and sex according to Canadian norms; controls were born at the same period and institution at or above the 10th percentiles and were matched on gestational age, race, and sex. Homocysteine was measured in cord and maternal blood. The analysis included 483 case and 468 control mothers and 409 case and 438 control newborns. RESULTS Homocysteine values were largely <15 micromol/L. Contrary to expectation, within that range of values, increased plasma homocysteine, particularly in the mother, was protective against intrauterine growth restriction. With the case/control status as the outcome, the estimated odds ratio was 0.37 (95% confidence interval, 0.24-0.58) for a 5 micromol/L unit difference on the maternal homocysteine scale. With birthweight as the outcome, the estimated increase was 178.1 g (95% confidence interval, 92.5-263.7 g) for every 5 micromol/L unit increase in maternal homocysteine. Results were similar using newborn homocysteine concentrations. CONCLUSIONS The data suggest that, in contrast to the proposed hypothesis, mothers with small babies have lower homocysteine concentrations than those giving birth to larger ones.
Collapse
Affiliation(s)
- Claire Infante-Rivard
- Department of Epidemiology, Biostatistics, and Occupational Health, Faculty of Medicine, McGill University, Montréal, Province of Québec, H3A 1A3 Canada.
| | | | | | | |
Collapse
|
27
|
|
28
|
Gerhard DS, Nguyen LT, Zhang ZY, Borecki IB, Coleman BI, Rader JS. A relationship between methylenetetrahydrofolate reductase variants and the development of invasive cervical cancer. Gynecol Oncol 2003; 90:560-5. [PMID: 13678724 DOI: 10.1016/s0090-8258(03)00368-8] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
OBJECTIVE Low red blood cell folate levels have been associated with hypomethylation of DNA in dysplastic tissue and an increased risk for cervical intraepithelial neoplasia in human papillomavirus (HPV)-infected women. Methylenetetrahydrofolate reductase (MTHFR) is a critical enzyme regulating the metabolism of folate and methionine, the important components of DNA synthesis and methylation. Two common genetic polymorphisms, causing reduced MTHFR activity, have been identified. Therefore, the goal of this study was to evaluate these MTHFR variations as risk factors for invasive cervical cancer. METHODS To overcome the failure to properly match cases and controls that can cause false-positive inferences due to population stratification and unrecognized variables in a traditional case-control study, a family-based transmission/disequilibrium test (TDT) was used. We obtained samples from nuclear families of 102 women with invasive cervical cancer (ICC). One polymorphism was typed by a PCR-RFLP method, while a template-directed dye-terminator assay was developed for the other. RESULTS AND CONCLUSIONS We were unable to confirm a strong association of MTHFR polymorphisms and ICC using family-based controls and a transmission/disequilibrium test. The overall results of the TDT showed chi(2) (1 df) of 0.28 (P = 0.60) for exon 4, chi(2) (1 df) of 0.81(P = 0.37) for exon 7, and chi(2) (3 df) of 2.56 (P = 0.46) for the haplotype, meaning that there was no transmission of those alleles significantly in excess of Mendelian expectations to affected women. In addition, there was no effect of these variants with increased parity or infection with high-risk-type human papillomavirus.
Collapse
Affiliation(s)
- D S Gerhard
- Department of Genetics, Washington University School of Medicine, St. Louis, MO 63110, USA.
| | | | | | | | | | | |
Collapse
|
29
|
Lathrop Stern L, Shane B, Bagley PJ, Nadeau M, Shih V, Selhub J. Combined marginal folate and riboflavin status affect homocysteine methylation in cultured immortalized lymphocytes from persons homozygous for the MTHFR C677T mutation. J Nutr 2003; 133:2716-20. [PMID: 12949355 DOI: 10.1093/jn/133.9.2716] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Methylenetetrahydrofolate reductase (MTHFR) catalyzes the reduction of 5,10-methylenetetrahydrofolate to 5-methyltetrahydrofolate, the methyl donor for the synthesis of methionine from homocysteine. A common C677T mutation in the MTHFR gene renders the enzyme approximately 50% less active than the wild-type enzyme as shown in in vitro studies using cell extracts. We developed an immortalized cell culture model to determine whether the lower in vitro activity imparted by the homozygous (T/T) genotype is demonstrated in situ when exposed to adequate and marginal physiologic concentrations of folate and riboflavin. T/T MTHFR activity was compared with that of C/C genotype cell extracts by an in vitro assay and in intact cells by measuring the distribution of folate forms, the accumulation of homocysteine in the medium and the synthesis of methionine from formate and homocysteine. Under adequate nutrient conditions, the in vitro activity of the T/T MTHFR enzyme was approximately half that of the C/C genotype. Similarly, the proportion of 5-methyltetrahydrofolate in cells with the T/T genotype was approximately half that of the cells with wild-type MTHFR. In contrast, homocysteine accumulation in the culture medium was low and not different between genotypes, nor was there a difference in methionine synthetic capacity. Significant differences were observed between genotypes only when the supply of both folate and riboflavin was limited in the medium, which resulted in increased homocysteine accumulation and decreased methionine production in the T/T genotype. These data are consistent with the current understanding of the molecular interaction of the MTHFR mutant with folate substrates and the FAD prosthetic group.
Collapse
Affiliation(s)
- Lori Lathrop Stern
- Vitamin Metabolism and Aging Laboratory, Jean Mayer US Department of Agriculture Human Nutrition Research Center on Aging at Tufts University, Boston, MA 02111, USA
| | | | | | | | | | | |
Collapse
|
30
|
Toffoli G, Cecchin E. Pharmacogenetics of stomach cancer. Suppl Tumori 2003; 2:S19-22. [PMID: 12914384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/04/2023]
Abstract
Conventionally adjustments of the dose of chemotherapeutic treatment could be uneffective in preventing toxicity and response variability. New strategies for individualization of treatment in cancer patients are becoming an emerging issue in the clinical practice. Pharmacogenetics is undoubtedly an important source of information in this respect deepening the complex correlation existing between individual genetic profile and the response to therapy in terms of toxicity and activity. Several polymorphisms, i.e. genetic mutations with a frequency > 1% in a given population, have been described for genes encoding proteins involved in the metabolism of the drugs employed in the treatment of gastric cancer. TS (thymidilate synthase) and DPD (dihydropyrimidine dehydrogenase) polymorphisms are implicated in the development of toxicity and in the efficacy of 5-fluorouracil (5FU). XRCC1 (X-ray cross-complementing group 1), ERCC1 (excision cross-complementing gene) and GSTP1 (glutathione S-transferase) have a role in the development of pharmacoresistance to platinum derivatives. MTHFR (5, 10 methylenetetrahydrofolate reductase) C677T polymorphism is important in methotrexate (MTX) metabolism. UGT1A1 (uridine diphoshate-glucuronosyltransferase 1A1) is involved on irinotecan metabolism. MRP2 (multi-drug resistance associated protein) and MDR1 (multi-drug resistance gene) are involved in irinotecan as well as anthracyclines transport. In conclusion, the clinical applications of pharmacogenetics could represent a new insight to accurately determine the proper drug and dose to be used in each individual patient.
Collapse
Affiliation(s)
- Giuseppe Toffoli
- Experimental and Clinical Pharmacology Unit, Centro di Riferimento Oncologico (CRO), National Cancer Institute, Via Pedemontana Occidentale 12, Aviano, PN
| | | |
Collapse
|
31
|
Visscher PM, Tynan M, Whiteman MC, Pattie A, White I, Hayward C, Wright AF, Starr JM, Whalley LJ, Deary IJ. Lack of association between polymorphisms in angiotensin-converting-enzyme and methylenetetrahydrofolate reductase genes and normal cognitive ageing in humans. Neurosci Lett 2003; 347:175-8. [PMID: 12875914 DOI: 10.1016/s0304-3940(03)00691-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The hypothesis that polymorphisms at two candidate genes that code for angiotensin-converting-enzyme (ACE) and methylenetetrahydrofolate reductase (MTHFR) are associated with normal cognitive ageing was tested using a sample (n=536) of healthy 80-year-old people who were born in 1921 and whose cognitive ability at age 11 was measured in the Scottish Mental Survey 1932. Cognitive ability at age 11 and age 80 was assessed using the Moray House Test. Cognitive ageing was defined as the change in IQ from age 11 to 80. There was no significant association between the tested ACE and MTHFR polymorphisms and IQ score at age 11, IQ at age 80, and IQ change (all P>0.05). The ACE genotypes deviated significantly from Hardy-Weinberg equilibrium proportions (P=0.02), which could indicate that this gene is under selection. Polymorphisms at the two studied genes are unlikely to be risk factors for normal cognitive ageing.
Collapse
Affiliation(s)
- Peter M Visscher
- Institute of Cell, Animal and Population Biology, University of Edinburgh, Edinburgh, UK
| | | | | | | | | | | | | | | | | | | |
Collapse
|
32
|
Abstract
High plasma levels of total homocysteine (tHcy) are a risk factor for deep vein thrombosis. Because no information on the relationship between cerebral vein thrombosis and hyperhomocysteinemia is available, a case-control study of 121 patients with a first episode of cerebral vein thrombosis and 242 healthy control subjects was carried out. Fasting plasma levels of tHcy and their postmethionine load (PML) increments, together with other laboratory markers of thrombophilia, were measured in plasma or DNA. Hyperhomocysteinemia (high fasting tHcy and/or PML increments) was diagnosed in 33 patients (27%) and 20 control subjects (8%) (odds ratio, 4.2; 95% confidence interval [CI], 2.3-7.6). Low levels of serum folate and the 677TT methylene tetrahydrofolate reductase were associated with hyperhomocysteinemia, but in a multivariate model hyperhomocysteinemia only was associated with an increased risk of cerebral vein thrombosis. Oral contraceptive intake was associated with the disease with an odds ratio of 6.1 (95% CI, 3.3-11.0). The combined presence of the latter and hyperhomocysteinemia increased the risk of the disease with an odds ratio of 19.5 (95% CI, 5.7-67.3). In conclusion, hyperhomocysteinemia is associated with a 4-fold increased risk of cerebral vein thrombosis; whether or not its correction with vitamins reduces the risk of the disease remains to be demonstrated.
Collapse
Affiliation(s)
- Ida Martinelli
- Angelo Bianchi Bonomi Hemophilia and Thrombosis Center, Department of Internal Medicine, Istituto di Ricovero e Cura a Carattere Scientifico, Ospedale Maggiore, University of Milan, Italy.
| | | | | | | | | |
Collapse
|
33
|
Kishi S, Griener J, Cheng C, Das S, Cook EH, Pei D, Hudson M, Rubnitz J, Sandlund JT, Pui CH, Relling MV. Homocysteine, pharmacogenetics, and neurotoxicity in children with leukemia. J Clin Oncol 2003; 21:3084-91. [PMID: 12915598 DOI: 10.1200/jco.2003.07.056] [Citation(s) in RCA: 153] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
PURPOSE Despite its clinical success, methotrexate (MTX) therapy is associated with toxicities such as seizures, the pathogenesis of which remains unclear. It has been suggested that hyperhomocysteinemia is caused by MTX and is responsible for its neurotoxic effects. The purposes of this study were to explore whether hyperhomocysteinemia was related to MTX administration and toxicity and whether homocysteine or MTX toxicity differed by methylenetetrahydrofolate reductase (MTHFR) or reduced folate carrier (RFC) genetic polymorphisms. PATIENTS AND METHODS We studied 53 children with newly diagnosed acute lymphoblastic leukemia who were consecutively treated on a single clinical protocol that included two courses of high-dose MTX (high-dose methotrexate [HDMTX]; 2.5 or 5.0 g/m2 per day) as consolidation therapy. RESULTS The study participants' median plasma homocysteine concentrations at 23 and 44 hours after HDMTX (9.00 micromol/L and 10.12 micromol/L, respectively) were greater than the concentrations immediately before HDMTX (5.77 micromol/L, P <.0001 for both comparisons). Seven days after HDMTX treatment, their plasma concentration returned to baseline. Nine patients experienced seizures, and five patients experienced thrombosis during the first 15 months of therapy, with a tendency for there to be higher plasma homocysteine in patients with seizures across all time points (P =.063) but not in patients with thrombosis (P =.59). We observed no significant differences in plasma or cerebrospinal fluid homocysteine levels or in toxicity based on the MTHFR 677C/T or RFC 80G/A genotypes. CONCLUSION We conclude that homocysteine was transiently elevated after HDMTX and may be related to seizure risk in children with leukemia.
Collapse
Affiliation(s)
- Shinji Kishi
- Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, 332 North Lauderdale, Memphis, TN 38105, USA
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
34
|
Dodson PM, Haynes J, Starczynski J, Farmer J, Shigdar S, Fegan G, Johnson RJ, Fegan C. The platelet glycoprotein Ia/IIa gene polymorphism C807T/G873A: a novel risk factor for retinal vein occlusion. Eye (Lond) 2003; 17:772-7. [PMID: 12928694 DOI: 10.1038/sj.eye.6700452] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Retinal vein occlusion (RVO) is associated with hyperhomocysteinaemia and the antiphospholipid syndrome-disorders known to contribute to both arterial and venous thrombosis. In both of these conditions and RVO, platelet activation occurs. Aspirin, not warfarin, is the most effective antithrombotic agent in RVO and, taken together, these observations suggest an important role for platelets in this common ocular thrombotic condition. Platelet glycoprotein Ia/IIa (GpIa/IIa) is an adhesion molecule mediating platelet-collagen interactions and is key to the initiation of thrombosis. Recently, the cellular density of this molecule was shown to be determined by two silent, linked polymorphisms (C807T/G873A) within the GpIa/IIa gene. There is evidence that some of the resulting genotypes are associated with thrombo-embolic disease. This study therefore aimed to establish the prevalence of the GpIa/IIa polymorphisms and the three commonest hereditary thrombophilic disorders (prothrombin gene G20210A (PT) mutation, Factor V Leiden (FVL), and the thermolabile methylene tetrahydrofolate reductase C677T (MTHFR) mutation) in patients with RVO and normal controls. The GpIa/IIa polymorphisms and thrombophilic abnormalities were all identified using the polymerase chain reaction.Our results show that the frequency of the GpIa/IIa polymorphisms was similar in our normal control population to previously published series. Patients with RVO, however, had only a 10% (4/40) frequency of the lowest risk subtype (CC/GG) compared to 37.5% (15/40) in the control group-P 0.0039. The incidence of the PT, FVL, and MTHFR thrombophilic mutations was not different between the two groups, but interestingly none of the 7/40 RVO cases with a PT, FVL, or MTHFR mutation had the low-risk GpIa/IIa genotype while all but one of the controls did-P<0.05. Thus, 17.5% of RVO patients harboured more than one prothrombotic abnormality. The principal difference between the RVO and control group was the very high incidence of the intermediate-risk GpIa/IIa subtype (CT/GA)-82.5 vs 50%, P&<0.05. These results suggest a major role for GpIa/IIa polymorphisms in the pathogenesis of RVO.
Collapse
Affiliation(s)
- P M Dodson
- Department of Medical Ophthalmology Heartlands Hospital Bordesley Green East Birmingham B9 5SS, UK
| | | | | | | | | | | | | | | |
Collapse
|
35
|
Abstract
Methlenetetrahydrofolate (CH2-H4folate) is required for the conversion of homocysteine to methionine and of dUMP to dTMP in support of DNA synthesis, and also serves as a major source of one carbon unit for purine biosynthesis. This review presents biochemical studies of a human polymorphism in methylenetetrahydrofolate reductase, which catalyzes the reaction shown below. The mutation decreases the flux of CH2-H4folate into CH3-H4folate, and is associated with both beneficial and deleterious effects that can be traced to the molecular effect of the substitution of alanine 222 by valine.
Collapse
Affiliation(s)
- Rowena G Matthews
- Biophysics Research Division, The University of Michigan, 930 N. University Avenue, Ann Arbor, Michigan 48109-1055, USA.
| |
Collapse
|
36
|
Abstract
Common single nucleotide polymorphisms (SNPs; 677C>T and 1298A>C) in the methylenetetrahydrofolate reductase gene ( MTHFR) decrease the activity of the enzyme, leading to hyperhomocysteinemia, particularly in folate-deficient states. We calculate herein the haplotype frequencies of the MTHFR 677 and 1298 polymorphisms in pooled general populations derived from published data. We selected 16 articles that provided reliable data on combined MTHFR genotypes in general populations ( n = 5389). The combined data comprised the following totals for each genotype at nucleotide positions 677 and 1298: 838 CC/AA (i.e., 677CC/1298AA), 1225 CC/AC, 489 CC/CC, 1120 CT/AA, 1093 CT/AC, 8 CT/CC, 606 TT/AA, 10 TT/AC, and 0 TT/CC. The estimated haplotype frequencies, and the fractional contribution of each, were 677C/1298A, 0.37; 677C/1298C, 0.31; 677T/1298A, 0.32; and 677T/1298C, 0.0023 to 0.0034. Thus, a vast majority of 677T alleles and 1298C alleles are associated with 1298A alleles and 677C alleles, respectively. There may be an increased frequency of the very rare cis 677T/1298C haplotype in some parts of the United Kingdom and Canada, possibly due to a founder effect. Further studies on both SNPs are needed to determine their exact role in various clinical settings.
Collapse
Affiliation(s)
- Shuji Ogino
- Department of Pathology, Brigham and Women's Hospital, 75 Francis St., Amory 3rd floor, Boston, MA 02115, USA.
| | | |
Collapse
|
37
|
Guéant-Rodriguez RM, Rendeli C, Namour B, Venuti L, Romano A, Anello G, Bosco P, Debard R, Gérard P, Viola M, Salvaggio E, Guéant JL. Transcobalamin and methionine synthase reductase mutated polymorphisms aggravate the risk of neural tube defects in humans. Neurosci Lett 2003; 344:189-92. [PMID: 12812837 DOI: 10.1016/s0304-3940(03)00468-3] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The pathogenic mechanism of neural tube defects may involve genetic polymorphisms and nutritional factors related to homocysteine metabolism. We evaluated the association of polymorphisms of three genes affecting vitamin B12-dependent remethylation of homocysteine, transcobalamin (TC), methionine synthase (MTR) and MTR reductase (MTRR), combined or not with methylenetetrahydrofolate reductase (MTHFR), with the risk of having neural tube defect in 40 children with spina bifida and 58 matched controls from South Italy. MTR 2756 AG/GG, TC 777 CG/GG /MTHFR 677 CC and MTRR 66 GG /MTHFR 677 CC genotypes increased the risk with odds ratios of 2.6 (P=0.046), 2.4 (P=0.028) and 4.5 (P=0.023), respectively. In contrast, MTHFR 677 TT was protective (odds ratio=0.11, P=0.009). In conclusion, genetic determinants affecting the cellular availability or MTRR-dependent reduction of B12 may increase the risk of spina bifida.
Collapse
Affiliation(s)
- R M Guéant-Rodriguez
- Cellular and Molecular Pathology in Nutrition, EMI - INSERM 0014 - URM IFREMER 20, Faculty of Medicine BP 184, 54500, Vandoeuvre lès Nancy, France
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
38
|
Affiliation(s)
- Rebecca R Selzer
- Department of Anesthesiology, University of Wisconsin Medical School, Madison, USA
| | | | | | | |
Collapse
|
39
|
Affiliation(s)
- Richard W Erbe
- Department of Pediatrics, School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA
| | | |
Collapse
|
40
|
Abstract
Despite recent efforts to identify susceptibility genes of preeclampsia, the genetic determinants of the condition remain ill-defined, as is the situation for most disorders of complex inheritance patterns. The angiotensinogen, factor V, and methylenetetrahydrofolate reductase genes have been investigated in different populations, as have other genes involved in blood pressure, vascular volume control, thrombophilia, lipid metabolism, oxidative stress, and endothelial dysfunction. The study of the genetics of complex traits is faced with both methodological and genetic issues; these include adequate sample size to allow for the identification of modest genetic effects, of gene-gene and gene-environment interactions, the study of adequate quantitative traits and extreme phenotypes, haplotype analyses, statistical genetics, genome-wide (hypothesis-free) versus candidate-gene (hypothesis-driven) approaches, and the validation of positive associations. The use of genetically well-characterized populations showing a founder effect, such as the French-Canadian population of Quebec, in genetic association studies, may help to unravel the susceptibility genes of disorders showing complex inheritance, such as preeclampsia. It is necessary to better evaluate the role of the fetal genome in the resulting predisposition to preeclampsia and its complications. Eventually, we may be able to integrate genetic information to better identify the women at risk of developing preeclampsia, and to improve the management of those suffering from this condition.
Collapse
Affiliation(s)
- Nathalie Bernard
- Unité de recherche en périnatalogie, Centre de recherche, Hôpital Saint-François d'Assise, Centre hospitalier universitaire de Québec, Québec, QC, Canada
| | | |
Collapse
|
41
|
Inamoto N, Katsuya T, Kokubo Y, Mannami T, Asai T, Baba S, Ogata J, Tomoike H, Ogihara T. Association of methylenetetrahydrofolate reductase gene polymorphism with carotid atherosclerosis depending on smoking status in a Japanese general population. Stroke 2003; 34:1628-33. [PMID: 12775885 DOI: 10.1161/01.str.0000075769.09092.82] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE The association of the methylenetetrahydrofolate reductase gene (MTHFR) with carotid atherosclerosis remains inconsistent. This may be due to small sample size and inappropriate analysis. We investigated the association of C677T/MTHFR with blood pressure and carotid atherosclerosis in a Japanese general population. METHODS Subjects (30 to 89 years of age; 1693 women, 1554 men) who gave informed consent were randomly selected from a general population in Suita, Japan. MTHFR genotypes were determined by TaqMan polymerase chain reaction. Carotid atherosclerosis was evaluated by high-resolution ultrasonography with atherosclerotic indexes of intimal-medial thickness (IMT), maximum IMT in the common carotid artery (CCA), plaque score, and stenosis (>50%). RESULTS Age-adjusted diastolic blood pressure was significantly higher in women with the TT genotype than in those with the CC genotype. In a recessive model (CC+CT versus TT), all adjusted odds ratios for hypertension and >50% stenosis in women were 1.42 and 3.42 (95% confidence intervals, 1.01 to 1.99 and 1.23 to 9.53), respectively. In women, maximum IMT in CCA for smokers with the TT genotype was significantly higher than for smokers with the CC genotype and nonsmokers with the TT genotype (P<0.05). CONCLUSIONS Our study suggests that the MTHFR TT genotype is a risk factor for hypertension and carotid stenosis in women. Significant interactions between C677T/MTHFR and smoking on maximum IMT in CCA were observed in women but not in men. Smoking cessation for subjects with the TT genotype is important in the prevention of cerebrovascular disease.
Collapse
Affiliation(s)
- Nozomu Inamoto
- Department of Geriatric Medicine, National Cardiovascular Center, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
| | | | | | | | | | | | | | | | | |
Collapse
|
42
|
Vaughn CP, Elenitoba-Johnson KSJ. Hybridization-induced dequenching of fluorescein-labeled oligonucleotides: a novel strategy for PCR detection and genotyping. Am J Pathol 2003; 163:29-35. [PMID: 12819008 PMCID: PMC1868185 DOI: 10.1016/s0002-9440(10)63627-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Fluorescence-based detection methods are being increasingly utilized in molecular analyses. Sequence-specific fluorescently-labeled probes are favored because they provide specific product identification. The most established fluorescence-based detection systems employ a resonance energy transfer mechanism effected through the interaction of two or more fluorophores or functional groups conjugated to oligonucleotide probes. The design, synthesis and purification of such multiple fluorophore-labeled probes can be technically challenging and expensive. By comparison, single fluorophore-labeled probes are easier to design and synthesize, and are straightforward to implement in molecular assays. We describe herein a novel fluorescent strategy for specific nucleic acid detection and genotyping. The format utilizes an internally quenched fluorescein-oligonucleotide conjugate that is subsequently dequenched following hybridization to the target with an attendant increase in fluorescence. Reversibility of the process with strand dissociation permits Tm-based assessment of bp complementarity and mismatches. Using this approach, we demonstrated specific detection, and discrimination of base substitutions of a variety of synthetic nucleic acid targets including Factor V Leiden and methylenetetrahydrofolate reductase. We further demonstrated compatibility of the novel chemistry with polymerase chain reaction by amplification and genotyping of the above listed loci and the human hemoglobin beta chain locus. In total, we analyzed 172 clinical samples, comprising wild-type, heterozygous and homozygous mutants of all three loci, with 100% accuracy as confirmed by DNA sequencing, established dual hybridization probe or high performance liquid chromatography-based methods. Our results indicate that the dequenching-based single fluorophore format is a feasible strategy for the specific detection of nucleic acids in solution, and that assays using this strategy can provide accurate genotyping results.
Collapse
Affiliation(s)
- Cecily P Vaughn
- ARUP Institute for Clinical and Experimental Pathology, Salt Lake City, Utah, USA
| | | |
Collapse
|
43
|
Martinelli I, Taioli E, Ragni G, Levi-Setti P, Passamonti SM, Battaglioli T, Lodigiani C, Mannucci PM. Embryo implantation after assisted reproductive procedures and maternal thrombophilia. Haematologica 2003; 88:789-93. [PMID: 12857558] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/03/2023] Open
Abstract
BACKGROUND AND OBJECTIVES Women undergoing assisted reproductive procedures, such as in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI), fail to achieve pregnancy in approximately 70% of cases. Postulating that among the possible causes of failure of embryo implantation might be an impairment of the uteroplacental circulation due to hypercoagulability in the mother, we investigated the association between thrombophilia and failure to achieve pregnancy after IVF or ICSI. DESIGN AND METHODS A case-control study was carried out in 234 women undergoing IVF or ICSI and in 234 women who, in the same period, conceived naturally. Thrombophilia due to mutations in genes encoding coagulation factor V (G1691A), prothrombin (G20210A), methylene-tetrahydrofolate reductase (C677T) and the presence of antiphospholipid antibodies was searched for. RESULTS The prevalence of factor V, prothrombin and methylene-tetrahydrofolate reductase mutations was similar in the 162 women who failed to achieve pregnancy after IVF or ICSI and in control women (5% and 2% for factor V G1691A, odd ratio 2.4, 95% CI 0.8-7.4; 3% and 6% for prothrombin G20210A, odds ratio 0.5, 95% CI 0.2-1.5; 19% and 20% for homozygous methylene-tetrahydrofolate reductase C677T, odds ratio 1.0, 95% CI 0.6-1.6). Nor was any association found when women who failed to achieve pregnancy were divided according to the total number of assisted reproductive procedures, age, type of procedure and cause of infertility. Antiphospholipid antibodies were not detected in any of the women. INTERPRETATION AND CONCLUSIONS This study provides no evidence for an association between maternal thrombophilia and failure to achieve pregnancy after assisted reproductive procedures. Routine anticoagulant treatment in women undergoing assisted reproductive procedures is not warranted.
Collapse
Affiliation(s)
- Ida Martinelli
- A. Bianchi Bonomi Hemophilia and Thrombosis Center, IRCCS Maggiore Hospital, University of Milano, Via Pace, 9, 20122 Milano, Italy.
| | | | | | | | | | | | | | | |
Collapse
|
44
|
Brown AT, Smith TP, Cruz CP, Poirier LA, Simmons D, Williams DK, Wang Y, Eidt JF, Moursi MM. Intimal hyperplasia following carotid endarterectomy in an insulin-resistant rat model. Metabolism 2003; 52:834-9. [PMID: 12870157 DOI: 10.1016/s0026-0495(03)00097-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Hyperhomocysteinemia, a known risk factor for cardiovascular disease, results in an elevation of intimal hyperplasia (IH) following a carotid endarterectomy (CEA) in a rat model. An exaggerated IH response following CEA has been observed in rats with dietary induced hyperhomocysteinemia. Type 2 diabetics often present with hyperhomocysteinemia and are at higher risk for developing vascular blockage following surgical procedures. To determine if insulin resistance increases IH risks following endarterectomy, the 3 goals of this study were: (1) to establish plasma homocysteine concentrations in dietary induced insulin-resistant rats and their controls, (2) to investigate whether a positive correlation of IH and plasma homocysteine response occurs following CEA in the insulin-resistant rat model, and (3) if so, to attempt to decrease IH by supplementation with folic acid, a known enzymatic cofactor in the homocysteine metabolic pathway. To achieve these aims, male rats (275 to 300 g) were fed 1 of 4 diets for a 4-month period: (1) high-fat sucrose (HFS), (2) low-fat complex carbohydrate (LFCC), (3) HFS + 25 mg/kg folic acid (HFS+F), or (4) LFCC + 25 mg/kg folic acid (LFCC+F). At the end of the 4-month period the rats underwent an open (non-balloon) unilateral CEA. Two weeks post-endarterectomy, blood, liver and carotid tissue were removed to measure plasma insulin, folic acid, and homocysteine, 2 key enzymes of homocysteine metabolism-methylenetetrahydrofolate reductase (MTHFR) and cystathionine beta-synthase (CBS)-and percent lumenal stenosis (IH%). Computer-assisted morphometric analysis was used to measure the percentage of IH in the carotid artery. Plasma homocysteine was significantly higher in the HFS group when compared with the LFCC group (11.3+/-1.3 micromol/L v 7.4+/-0.6 mircomol/L, P=.008) as was post-endarterectomy IH producing lumenal stenosis (30.7%+/-4.2% v 14.0%+/-4.3%, P=.008). Plasma insulin in the HFS group was higher than the LFCC (control) group and was significant (36.3+/-3.0 microU/mL v 21.1+/-0.8 microU/mL, P=.0004). Folic acid supplementation in the HFS group resulted in reductions of plasma homocysteine (HFS v HFS+F, 11.3+/-1.3 micromol/L v 7.95+/-1.0 micromol/L, P=.02) and post-endarterectomy IH (HFS v HFS+F, 30.7%+/-4.2 % v 10.4%+/-1.6%, P=.0001). The control or LFCC group was not statistically different from the HFS+F group in homocysteine or IH. Folate supplementation did not decrease insulin concentrations in the HFS+F group compared to the LFCC group. We conclude that the HFS diet produced an insulin-resistant state with an elevated plasma homocysteine and an exaggerated IH response following carotid endarterectomy in this rat model. Dietary folate supplementation reduced plasma homocysteine concentrations in the HFS diet, which implicates hyperhomocysteinemia as an etiologic factor in the development of post-CEA IH in this insulin-resistant rat model.
Collapse
Affiliation(s)
- Aliza T Brown
- Department of Surgery, Division of Vascular Surgery, Central Arkansas Veterans Healthcare System, Little Rock, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
45
|
Balta G, Yuksek N, Ozyurek E, Ertem U, Hicsonmez G, Altay C, Gurgey A. Characterization of MTHFR, GSTM1, GSTT1, GSTP1, and CYP1A1 genotypes in childhood acute leukemia. Am J Hematol 2003; 73:154-60. [PMID: 12827651 DOI: 10.1002/ajh.10339] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The role of methylenetetrahydrofolate reductase (MTHFR C677T), glutathione S-transferases (GSTM1 and GSTT1 null, GSTP1 Ile105Val), and cytochromes p450 (CYP1A1*2A) genotypes in the etiology of childhood leukemia was simultaneously investigated. 144 Turkish children with acute lymphoblastic leukemia (ALL) and 33 with acute nonlymphoblastic leukemia (ANLL) were studied and compared with 185 healthy pediatric controls. The frequency of MTHFR genotype was insignificantly higher in ALL (7.7%) and ANLL (6.3%) than in controls (4.4%). Equal distribution of the GSTM1 null genotype was detected between ALL patients and controls (55%), while its incidence was slightly higher in ANLL patients (61.3%). Although GSTT1 null genotype was insignificantly lower in ALL patients (20.9%) than controls (22.7%), it was significantly underrepresented in ANLL patients (6.5%) (P = 0.05, OR 0.24, 95% CI 0.05-1.03). The homozygous frequency of GSTP1 genotype did not differ significantly between groups of ALL (3.7%), ANLL patients (9.1%) and controls (4.9%). Homozygous CYP1A1*2A genotype was underrepresented in ALL patients (1%) as compared to control (4.8%) but the differences did not reach to statistical significance (OR 0.21; 95% CI 0.03-1.72). Homozygosity for this genotype was not detected in ANLL patients. No particular association was noted between different combinations of combined genotypes and risk of development of childhood ALL and ANLL. These results suggested that there are no significant associations between the studied genotypes and the risk of developing either form of acute leukemia except GSTT1 null and homozygosity for CYP1A1 genotypes that may play protective roles in the development of ANLL in Turkish children.
Collapse
Affiliation(s)
- Gunay Balta
- Hacettepe University, Faculty of Medicine, Department of Pediatrics, Institute of Child Health and Section of Pediatric Hematology, Ankara, Turkey.
| | | | | | | | | | | | | |
Collapse
|
46
|
Jugessur A, Wilcox AJ, Lie RT, Murray JC, Taylor JA, Ulvik A, Drevon CA, Vindenes HA, Abyholm FE. Exploring the effects of methylenetetrahydrofolate reductase gene variants C677T and A1298C on the risk of orofacial clefts in 261 Norwegian case-parent triads. Am J Epidemiol 2003; 157:1083-91. [PMID: 12796044 DOI: 10.1093/aje/kwg097] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Folic acid and the methylenetetrahydrofolate reductase (MTHFR) gene have both been implicated in the etiology of orofacial clefts. The authors selected 261 case-parent triads (173 cases with cleft lip with or without cleft palate (CL/P) and 88 cases with cleft palate only (CPO)) from a Norwegian population-based study of orofacial clefts (May 1996-1998). A case-parent triad design was used to examine whether MTHFR variants C677T and A1298C, and their haplotypes, are risk factors for orofacial clefts. Among CL/P cases, the child's genotype at C677T or A1298C did not influence the risk. However, children of mothers carrying the C677T variant allele had a lower risk of CL/P. For CPO, children carrying the C677T variant allele had about a twofold increased risk, whereas the mother's genotypes did not contribute to the risk. The haplotype-based transmission/disequilibrium test showed that except for 677T/1298A (p = 0.06), none of the other haplotypes showed evidence of excess transmission to the offspring. The authors also explored interaction of C677T with maternal use of folic acid among children with CPO. Surprisingly, the risk associated with the child's carrying either CT or TT was higher (fourfold) when the mother used folic acid. These findings suggest a possible role of MTHFR and folic acid in the causation of orofacial clefts, but the strength and direction of these effects remain to be clarified.
Collapse
Affiliation(s)
- Astanand Jugessur
- Center for Medical Genetics and Molecular Medicine, Haukeland University Hospital, Bergen, Norway.
| | | | | | | | | | | | | | | | | |
Collapse
|
47
|
Ling KH, Rosli R, Duraisamy G, Nasir MT. The prevalence of MTHFR 677C-->T missense mutation, total plasma homocysteine levels and associated risk factors in Malay subjects. Med J Malaysia 2003; 58:243-54. [PMID: 14569745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/27/2023]
Abstract
The missense mutation of the methylenetetrahydrofolate reductase (MTHFR) gene 677C-->T is associated with modest elevation of homocysteine levels. The bio-ecogenetics factors of total homocysteine levels (tHcy) were investigated in a cross sectional study involving 53 randomly selected healthy Malay subjects. Results indicated that the prevalence of the homozygous 677T/T was 3.8% and heterozygous 677C/T was 17.0%. The levels of tHcy was higher in subjects aged more than 50 years (n = 7, 11.53 +/- 4.45 mumol/l) and in males (10.99 +/- 3.77 mumol/l) especially smoking males (12.19 +/- 3.62 mumol/l). THcy levels were low in the 3 pregnant subjects (4.44 mumol/l, p = 0.036) who were under folate supplementation.
Collapse
Affiliation(s)
- K H Ling
- Department of Human Growth and Development, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor Darul Ehsan
| | | | | | | |
Collapse
|
48
|
Kelly PJ, Shih VE, Kistler JP, Barron M, Lee H, Mandell R, Furie KL. Low vitamin B6 but not homocyst(e)ine is associated with increased risk of stroke and transient ischemic attack in the era of folic acid grain fortification. Stroke 2003; 34:e51-4. [PMID: 12738890 DOI: 10.1161/01.str.0000071109.23410.ab] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE The introduction of cereal grain folic acid fortification in 1998 has reduced homocyst(e)ine (tHcy) concentrations in the US population. We performed a case-control study to determine the risk of stroke and transient ischemic attack (TIA) associated with tHcy and low vitamin status in a postfortification US sample. METHODS Consecutive cases with new ischemic stroke/TIA were compared with matched controls. Fasting tHcy, folate, pyridoxal 5'-phosphate (PLP), B12, and MTHFR 677C-->T genotype were measured. RESULTS Mean PLP was significantly lower in cases than controls (39.97 versus 84.1 nmol/L, P<0.0001). After stroke risk factors were controlled for, a strong independent association was present between stroke/TIA and low PLP (adjusted odds ratio [OR], 4.6; 95% CI, 1.4 to 15.1; P<0.001) but not elevated tHcy (OR, 0.92; 95% CI, 0.4 to 2.1). CONCLUSIONS Low B6 but not tHcy was strongly associated with cerebrovascular disease in this postfortification, folate-replete sample.
Collapse
Affiliation(s)
- Peter J Kelly
- Stroke Service, Department of Neurology, VBK 802, Massachusetts General Hospital, Fruit St, Boston, MA 02114, USA.
| | | | | | | | | | | | | |
Collapse
|
49
|
Zijno A, Andreoli C, Leopardi P, Marcon F, Rossi S, Caiola S, Verdina A, Galati R, Cafolla A, Crebelli R. Folate status, metabolic genotype, and biomarkers of genotoxicity in healthy subjects. Carcinogenesis 2003; 24:1097-103. [PMID: 12807760 DOI: 10.1093/carcin/bgg064] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Gene-environment interactions play an important role in folate metabolism, with a potential impact on human health. Deficiencies in the uptake of key micronutrients and variant genotypes can affect the folic acid cycle, modulating methyl group transfer in key processes and leading to increased cancer risk and Down syndrome incidence. So far, the significance of folate status and metabolic genotypes on baseline levels of DNA damage in normal individuals has not been fully elucidated. In this study, the possible modulation of SCE, micronuclei and tail moment values in peripheral lymphocytes by plasma levels of folic acid, homocysteine and vitamin B12, and by the methylenetetrahydrofolate reductase (MTHFR) C677T and methionine synthase reductase (MTRR) A66G polymorphisms was investigated in 191 healthy subjects. The results obtained show a highly significant (P = 0.001) positive association between plasma levels of vitamin B12 and frequencies of both SCE and high frequency cells (HFC, above 90 degrees percentile) in smokers. No significant effect was observed in non-smokers. Moreover, after correction for age, gender and GSTM1 genotype, a significant association (P = 0.026) between the MTRR 66GG variant genotype and higher micronucleus rates was observed. Tail moment values were not affected by any of the independent variables considered. Overall, the results obtained suggest that both folate status and relevant metabolic genotype can influence background levels of DNA damage in normal subjects. The significant association observed in smokers between plasma vitamin B12 and SCE frequencies may highlight the effect of methylation status on DNA damage and repair, although the role of other, unidentified dietary factors cannot be ruled out. At the same time, micronucleus data indicate that the MTRR 66GG variant may represent another individual trait of relative genomic instability, thus supporting epidemiological data on increased risk of Down syndrome conception in MTRR 66GG subjects.
Collapse
Affiliation(s)
- A Zijno
- Laboratory of Comparative Toxicology and Ecotoxicology, Istituto Superiore di Sanità, Viale Regina Elena 299, I-00161, Rome, Italy
| | | | | | | | | | | | | | | | | | | |
Collapse
|
50
|
Brilakis ES, Berger PB, Ballman KV, Rozen R. Methylenetetrahydrofolate reductase (MTHFR) 677C>T and methionine synthase reductase (MTRR) 66A>G polymorphisms: association with serum homocysteine and angiographic coronary artery disease in the era of flour products fortified with folic acid. Atherosclerosis 2003; 168:315-22. [PMID: 12801615 DOI: 10.1016/s0021-9150(03)00098-4] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
We analyzed the association between the methylenetetrahydrofolate reductase (MTHFR) 677C>T and methionine synthase reductase (MTRR) 66A>G polymorphisms with serum homocysteine and with coronary artery disease (CAD) in 504 patients undergoing clinically-indicated angiography between July 1998 and January 1999. Significant CAD (>/=50% stenosis in >/=one artery, blinded to risk factors) was present in 271 patients (54%). Median homocysteine (micromol/l) was 8.8 (interquartile range: 7.5-10.7). The prevalence of the MTHFR TT, CT, and CC genotypes was 11, 44 and 45%, respectively. Median tHcy (with interquartile ranges) for the entire population was 8.8 (7.5-10.7), and for the TT, CT, and CC genotypes was 9.7 (8.2-11.4), 8.8 (7.5-10.7), and 8.6 (7.3-10.6) micromol/l, respectively (P=0.04). On multiple logistic regression analysis, the MTHFR TT genotype was associated with hyperhomocysteinemia (adjusted OR=3.57; 95% CI, 1.47-8.70), but not with significant CAD. The prevalence of the MTRR AA, AG, GG genotypes was 19, 50 and 31%, respectively. There were no differences in mean homocysteine, prevalence of hyperhomocysteinemia and significant CAD between the three genotypes. On multivariate analysis, the MTRR genotypes were not associated with serum homocysteine or with significant CAD.
Collapse
Affiliation(s)
- Emmanouil S Brilakis
- Division of Cardiovascular Diseases, Department of Internal Medicine, W16 Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
| | | | | | | |
Collapse
|