The influence of methylenetetrahydrofolate reductase C677T genotype and folate status on deoxyribonucleic acid methylation and uracil misincorporation in the colon of healthy volunteers
Ontology highlight
ABSTRACT:
DISEASE(S): Colorectal Cancer
PROVIDER: 2417579 | ecrin-mdr-crc |
REPOSITORIES: ECRIN MDR
Similar Datasets
Project description:Previous studies in our laboratory have shown that low folate diet (control diet with 2mg folate/kg, low folate diet with 0.3mg folate/kg) can induce intestinal tumors in BALB/c mice. We used microarrays to compare MTHFR+/+ BALB/c mice fed control diet and MTHFR+/- BALB/c mice fed low folate diet. After weaning, 4 BALB/c Mthfr +/+ mice were fed with a control diet (CD, 2mg folate/kg) and 4 BALB/c Mthfr +/- mice were fed a low folate diet (FD, 0.3mg folate/kg) for 1 year. Both diets contain succinylsulfanthiozole (1%) to prevent folate synthesis by intestine microbial biota.
2013-12-03 | E-GEOD-34011 | biostudies-arrayexpress
Project description:Previous studies in our laboratory have shown that low folate diet (control diet with 2mg folate/kg, low folate diet with 0.3mg folate/kg) can induce intestinal tumors in BALB/c mice. We used microarrays to compare MTHFR+/+ BALB/c mice fed control diet and MTHFR+/- BALB/c mice fed low folate diet.
2013-12-03 | GSE34011 | GEO
Project description:5, 10-Methylenetetrahydrofolate reductase (MTHFR) is a crucial enzyme in the folate metabolic pathway with a key role in generating methyl groups. As MTHFR deficiency impacts male fertility and sperm DNA methylation, there is the potential for epimutations to be passed to the next generation. Here, we assessed whether the impact of MTHFR deficiency on testis morphology and sperm DNA methylation is exacerbated across generations. While MTHFR deficiency in F1 fathers has only minor effects on sperm counts and testis weights and histology, F2 generation sons show further deterioration in reproductive parameters. Extensive loss of DNA methylation is observed in both F1 and F2 sperm, with >80% of sites shared between generations, suggestive of regions consistently susceptible to MTHFR deficiency. These regions are generally methylated during late prenatal germ cell development and are enriched in young retrotransposons. As retrotransposons are resistant to reprogramming of DNA methylation in prenatal germ cells, their hypomethylated state in the sperm of F1 males could contribute to the worsening reproductive phenotype observed in F2 MTHFR- deficient males, findings compatible with the intergenerational passage of epimutations.
2021-06-28 | GSE166586 | GEO
Project description:5,10-Methylenetetrahydrofolate reductase (MTHFR) is an enzyme that plays a key role in providing methyl groups for DNA methylation, including during spermatogenesis. A common genetic variant in humans (MTHFR 677C>T), results in reduced enzyme activity and has been linked to various disorders, including male infertility. A new animal model has been created by reproducing the human equivalent of the polymorphism in mice using CRISPR/Cas9. Biochemical parameters in the Mthfr 677TT mice recapitulate alterations found in MTHFR 677TT men. Our aims were to: 1) characterize the sperm DNA methylome of the Mthfr 677CC and TT mice on a control diet (2mg folic acid/kg diet) and 2) assess the effects of folic acid deficiency (0.3mg/kg diet) and supplementation (10 mg/kg diet) on the sperm DNA methylome. Body and reproductive organ weights, testicular sperm counts, and histology were examined. DNA methylation in sperm was assessed using bisulfite pyrosequencing, Illumina Mouse Methylation Array and whole genome bisulfite sequencing. Reproductive parameters and imprinted gene methylation were unaffected by genotype or diets. The largest effect was due to genotype, with sperm from 677TT mice showing more hypo- than hypermethylation. Folate-deficient diets resulted in sperm hyper- and hypomethylation in CC and TT mice. Folic acid supplementation caused mostly hypermethylation in sperm of males of both genotypes and was found to partially correct the DNA methylation alterations in sperm associated with the TT genotype. The new mouse model will be useful in understanding the role of MTHFR deficiency in male fertility and in designing folate supplementation regimens for the clinic.
2024-04-17 | GSE240712 | GEO
Project description:Dietary folate is a major source of methyl groups required for DNA methylation, an epigenetic modification that is actively maintained and remodelled during spermatogenesis. While high dose folic acid supplementation (up to ten times the daily recommended dose) has been shown to improve sperm parameters in infertile men, the effects of supplementation on the sperm epigenome are unknown. To assess the impact of six months of high dose folic acid supplementation on the sperm epigenome, we studied 30 men with idiopathic infertility. Blood folate concentrations increased significantly after supplementation with no significant improvements in sperm parameters. Methylation levels of the differentially methylated regions of several imprinted loci (H19, DLK1/GTL2, MEST, SNRPN, PLAGL1, KCNQ1OT1) were normal both before and after supplementation. Reduced representation bisulfite sequencing (RRBS) revealed a significant global loss of methylation across different regions of the sperm genome. The most marked loss of DNA methylation was found in sperm from patients homozygous for the methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism, a common polymorphism in a key enzyme required for folate metabolism. RRBS analysis also showed that most of the differentially methylated tiles were located in DNA repeats, low CpG density and intergenic regions. Ingenuity Pathway Analysis revealed that methylation of promoter regions was altered in several genes involved in cancer and neurobehavioral disorders including CBFA2T3, PTPN6, COL18A1, ALDH2, UBE4B, ERBB2, GABRB3, CNTNAP4 and NIPA1. Our data reveal alterations of the human sperm epigenome associated with high dose folic acid supplementation, effects that were exacerbated by a common polymorphism in MTHFR. Reduced representation bisulfite sequencing of 28 human sperm samples before and after 6 month of high dose folic acid supplementation.
2015-09-10 | E-GEOD-72606 | biostudies-arrayexpress
Project description:Supplementation with high doses of folic acid, an important mediator of one-carbon transfers for DNA methylation, is used clinically to improve sperm parameters in infertile men. We recently detected an unexpected loss of DNA methylation in the sperm of idiopathic infertile men after 6 months of daily supplementation with 5mg folic acid (>10× the daily recommended intake-DRI), exacerbated in men homozygous for a common variant in the gene encoding an important enzyme in folate metabolism, methylenetetrahydrofolate reductase (MTHFR 677C>T). To investigate the epigenomic impact and mechanism underlying effects of folic acid on male germ cells, wildtype and heterozygote mice for a targeted inactivation of the Mthfr gene were fed high-dose folic acid (10× the DRI) or control diets for six months. No changes were detected in general health, sperm counts or methylation of imprinted genes. Reduced representation bisulfite sequencing revealed sperm DNA hypomethylation in Mthfr+/- mice on the 10× diets. Wildtype mice demonstrated sperm hypomethylation only with a very high dose (20×) of folic acid for 12 months. Testicular MTHFR protein levels decreased significantly in wildtype mice on the 20× diet but not in those on the 10× diet, suggesting a possible role for MTHFR deficiency in sperm DNA hypomethylation. In-depth analysis of the folic acid-exposed sperm DNA methylome suggested mouse/human susceptibility of sequences with potential importance to germ cell and embryo development. Our data provide evidence for a similar cross-species response to high dose folic acid supplementation, of sperm DNA hypomethylation, and implicate MTHFR downregulation as a possible mechanism.
2018-01-23 | GSE100849 | GEO
Project description:Dietary folate is a major source of methyl groups required for DNA methylation, an epigenetic modification that is actively maintained and remodelled during spermatogenesis. While high dose folic acid supplementation (up to ten times the daily recommended dose) has been shown to improve sperm parameters in infertile men, the effects of supplementation on the sperm epigenome are unknown. To assess the impact of six months of high dose folic acid supplementation on the sperm epigenome, we studied 30 men with idiopathic infertility. Blood folate concentrations increased significantly after supplementation with no significant improvements in sperm parameters. Methylation levels of the differentially methylated regions of several imprinted loci (H19, DLK1/GTL2, MEST, SNRPN, PLAGL1, KCNQ1OT1) were normal both before and after supplementation. Reduced representation bisulfite sequencing (RRBS) revealed a significant global loss of methylation across different regions of the sperm genome. The most marked loss of DNA methylation was found in sperm from patients homozygous for the methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism, a common polymorphism in a key enzyme required for folate metabolism. RRBS analysis also showed that most of the differentially methylated tiles were located in DNA repeats, low CpG density and intergenic regions. Ingenuity Pathway Analysis revealed that methylation of promoter regions was altered in several genes involved in cancer and neurobehavioral disorders including CBFA2T3, PTPN6, COL18A1, ALDH2, UBE4B, ERBB2, GABRB3, CNTNAP4 and NIPA1. Our data reveal alterations of the human sperm epigenome associated with high dose folic acid supplementation, effects that were exacerbated by a common polymorphism in MTHFR.
2015-09-10 | GSE72606 | GEO
Project description:Periconceptual supplementation of women with folate is considered a great success for public health. Higher folate status, either by supplementation, or via the mandatory fortification of grain products in the United States, has lead to significant reduction in the incidence of neural tube defects. Besides birth defects, folate deficiency has been linked to a variety of morbidities, most notably to increased risk for cancer. However, recent evidence suggests that excess folate may be detrimental - for birth defect incidence or in the progression of cancer. How folate mediates beneficial or detrimental effects is not well understood. It is also unknown what molecular responses are elicited in women taking folate supplements, and thus experience a bolus of folate on top of the status achieved by fortification. To characterize this response, we performed gene expression profiling experiments on uterus tissue of pregnant mice after a preconceptional regimen of supplementation with folinic acid. We suggest that folinic acid supplementation affects expression of genes that contribute to protein synthesis and localization, genes that play a role for mitochondrial biology and oxidative phosphorylation, and genes encoding nucleotide-binding proteins, including protein kinases and GTP-binding intracellular signaling factors. The extent of such a response is strongly modulated by the genetic background. Finally, we suggest that folinic acid supplementation in this paradigm may affect histone methylation status, a potential avenue to mechanisms of gene regulation.
2013-03-31 | GSE36974 | GEO
Project description:Periconceptual supplementation of women with folate is considered a great success for public health. Higher folate status, either by supplementation, or via the mandatory fortification of grain products in the United States, has lead to significant reduction in the incidence of neural tube defects. Besides birth defects, folate deficiency has been linked to a variety of morbidities, most notably to increased risk for cancer. However, recent evidence suggests that excess folate may be detrimental - for birth defect incidence or in the progression of cancer. How folate mediates beneficial or detrimental effects is not well understood. It is also unknown what molecular responses are elicited in women taking folate supplements, and thus experience a bolus of folate on top of the status achieved by fortification. To characterize this response, we performed gene expression profiling experiments on uterus tissue of pregnant mice after a preconceptional regimen of supplementation with folinic acid. We suggest that folinic acid supplementation affects expression of genes that contribute to protein synthesis and localization, genes that play a role for mitochondrial biology and oxidative phosphorylation, and genes encoding nucleotide-binding proteins, including protein kinases and GTP-binding intracellular signaling factors. The extent of such a response is strongly modulated by the genetic background. Finally, we suggest that folinic acid supplementation in this paradigm may affect histone methylation status, a potential avenue to mechanisms of gene regulation. Gene expression profiles were generated from uterus tissue. Female mice were either C57BL/6 wildtype, or homozygous for a Folr4 mutation, and received injections of either saline of folininc acid, respectively.
2013-03-31 | E-GEOD-36974 | biostudies-arrayexpress
Project description:Deciphering the impact of metabolic intervention on response to anticancer therapy represents a path toward improved clinical responses. Here, we identify amino acid-related pathways connected to the folate cycle whose activation predicts sensitivity to MYC-targeting therapies in acute myeloid leukemia (AML). We establish that folate restriction and deficiency of the rate-limiting folate-cycle enzyme, MTHFR ― which exhibits reduced-function polymorphisms in about 10% of Caucasians ― enhance resistance to MYC targeting by BET and CDK7 inhibitors in cell lines, primary patient samples and syngeneic mouse models of AML. Further, this effect is abrogated by supplementation with the MTHFR enzymatic product, CH3-THF. Mechanistically, folate cycle disturbance reduces H3K27/K9 histone methylation, and activates a SPI1 transcriptional program counteracting the effect of BET inhibition. Our data provide a rationale for screening MTHFR polymorphisms and the folate cycle status to exclude patients least likely and nominate those most likely to benefit from MYC-targeting therapies.
2020-10-12 | GSE152441 | GEO