Project description:Study question: Do short-term and long-term exposures to low dose folic acid supplementation alter DNA methylation in sperm? Summary answer: No alterations in sperm DNA methylation patterns were found following the administration of low dose folic acid supplements of 400 μg/day for 90 days (short-term exposure) or when pre-fortification of food with folic acid and post-fortification sperm samples (long-term exposure) were compared. What is known already: Excess dietary folate may be detrimental to health and DNA methylation profiles due to folate’s role in one carbon metabolism and the formation of S-adenosyl methionine, the universal methyl donor. DNA methylation patterns are established in developing male germ cells and have been suggested to be affected by high dose (5 mg/day) folic acid supplementation. Participants/materials, setting, methods: Blood and seminal plasma folate levels were measured in participants before and following the 90-day treatment with placebo or supplement. Sperm DNA methylation was assessed using the whole genome and genome-wide techniques, MassArray epityper, restriction landmark genomic scanning, methyl-CpG immunoprecipitation and Illumina HumanMethylation450 Bead Array. Main results and the role of chance: Following treatment, supplemented individuals had significantly higher levels of blood and seminal plasma folates compared to placebo. Initial first generation genome-wide analyses of sperm DNA methylation showed little evidence of changes when comparing pre- and post-treatment samples. With Illumina HumanMethylation450 BeadChip arrays, no significant changes were observed in individual probes following low-level supplementation; when compared with those of the post-fortification cohort, there were also few differences in methylation despite exposure to years of fortified foods. Limitations, reasons for caution: This study was limited to the number of participants available in each cohort, in particular those who were not exposed to early (pre-1998) fortification of food with folic acid. While genome-wide DNA methylation was assessed with several techniques that targeted genic and CpG rich regions, intergenic regions were less well interrogated. Wider implications of the findings: Overall, our findings provide evidence that short term exposure to low dose folic acid supplements of 400 μg/day, over a period of 3 months, a duration of time that might occur during infertility treatments, has no major impact on the sperm DNA methylome.

Project description:Vitamin B-6, folate and homocysteine may play a critical role in the colorectal cancer progression. This is a 4-y study and the specific aims are: 1) to compare vitamin B-6, folate and homocysteine status, oxidative stress, antioxidant activities and DNA methylation between subjects with colorectal polyps and colorectal cancer; 2) to study the effects of vitamin B-6, folate and homocysteine status on oxidative stress, antioxidant activities and DNA methylation in colorectal cancer patients; 3) to evaluate whether folic acid and/or pyridoxine supplementation had a beneficial effect on oxidative stress, antioxidant activities and DNA methylation in patients with colorectal; 4) to compare vitamin B-6, folate and homocysteine status, oxidative stress, antioxidant activities and DNA methylation between colorectal cancer patients and age-, sex-matched healthy subjects; 5) to evaluate the effect of vitamin B-6, folate and homocysteine status, oxidative stress, antioxidant activities and DNA methylation on the risk of colorectal cancer (odds ratio); 6) to follow the effects of vitamin B-6, folate and homocysteine status, oxidative stress, antioxidant activities and DNA methylation on the occurrence of colorectal cancer; 7) to follow the effects of pyridoxine and/or folic acid supplementation on the occurrence of colorectal cancer. This protocol is designed as a hospital-based cross-sectional, case-control, double blinded randomized placebo-controlled intervention and follow-up trial. Three hundred colorectal cancer patients and 300 age-, sex-matched controls who meet the inclusion criteria will be recruited from Taichung General Veterans Hospital. If cancer patients’ plasma pyridoxal 5’-phosphate (PLP) level less than 30 nmol/L will be asked to participate the intervention study and will be blinded and randomly assigned to either the 1) control (vitamin C, 100 mg/d); 2) 50 mg vitamin B-6; 3) 400 microgram/d folic acid; or 4) vitamin B-6 (50 mg/d) plus folic acid (400 microgram/d) for 1 year. Data on demography, anthropometry, medical history, food frequency questionnaire and 24-h diet recall will be collected. Cancer patients will have fasting blood drawn before surgery or receiving chemotherapy. Additionally, fasting blood samples will be obtained at month 0, 3, 6, 9 and 12 during intervention period and at month 6, 12, 18, 24, 30, 36, 42 and 48 during follow-up. Hematological, plasma and erythrocyte PLP, plasma pyridoxal and 4-pyridoxic acid, serum and erythrocyte folate, serum vitamin B-12, homocysteine, SAM, SAH, lipid peroxidation indicators (TBARS, oxidized LDL), glutathione, antioxidant enzymatic activities and DNA methylation and MTHFR 677C>T polymorphism will be measured.

Project description:Background: We tested the hypothesis that short-term supplementation with a physiological dose of folate can alter global gene expression in the colon of subjects with colorectal adenoma using a randomised double blind placebo controlled trial design. Materials and Methods: Fourteen subjects with histologically confirmed colorectal adenoma, randomised to receive folic acid (400M-BM-5g/d, n=6) or placebo (n=8) for 10 weeks, had blood samples and colonic tissue biopsies collected before and after the intervention. Blood samples were used to determine serum and red cell folate, plasma homocysteine, and genetic polymorphisms in methylenetetrahydrofolate reductase (MTHFR C677T) and methionine synthase (MS A2756G). RNA extracted from normal-appearing colonic tissue samples was used to determine global gene expression in the colon using AffymetrixM-oM-^CM-^R Microarray GeneChips. Microarray results were confirmed by quantitative real time RT-PCR. Two methods were used to analyse the microarray data: (1) differences between pre- and post-intervention gene expression values in the folic acid and placebo groups separately using paired-sample t tests; (2) differences between the folic acid and placebo groups in the ratio of post-intervention to pre-intervention gene expression values using independent sample t-tests. Results: (1) Following intervention, sixty seven genes were up-regulated and 13 genes were down-regulated in the folic acid group, while 21 genes were up-regulated and none were down-regulated in the placebo group (P<0.05, adjusted for multiple testing). (2) Thirty six genes were up-regulated and 18 genes were down-regulated in the folic acid group when compared with placebo, but none of these were statistically significant after adjustment for multiple testing. These genes are involved in multiple pathways, including cell cycle, signal transduction, cell differentiation, transport, cell division, cell motility, protein transport and immune response. There were no genes involved in 1-carbon metabolism that were altered in expression, although several genes involved in neoplasia were up-regulated. Conclusions: These results indicate that while folic acid can modify gene expression, it is difficult to separate its effects from the natural variability in gene expression in the colon. Fourteen patients with colorectal adenoma were treated with either folate supplementation (6 subjects) or a placebo (8 subjects) for 10 weeks in a randomised double-blind trial. Colonic biopsies of normal tissue were taken before and after the intervention, and analysed for gene expression.

Project description:Background: We tested the hypothesis that short-term supplementation with a physiological dose of folate can alter global gene expression in the colon of subjects with colorectal adenoma using a randomised double blind placebo controlled trial design. Materials and Methods: Fourteen subjects with histologically confirmed colorectal adenoma, randomised to receive folic acid (400µg/d, n=6) or placebo (n=8) for 10 weeks, had blood samples and colonic tissue biopsies collected before and after the intervention. Blood samples were used to determine serum and red cell folate, plasma homocysteine, and genetic polymorphisms in methylenetetrahydrofolate reductase (MTHFR C677T) and methionine synthase (MS A2756G). RNA extracted from normal-appearing colonic tissue samples was used to determine global gene expression in the colon using Affymetrix Microarray GeneChips. Microarray results were confirmed by quantitative real time RT-PCR. Two methods were used to analyse the microarray data: (1) differences between pre- and post-intervention gene expression values in the folic acid and placebo groups separately using paired-sample t tests; (2) differences between the folic acid and placebo groups in the ratio of post-intervention to pre-intervention gene expression values using independent sample t-tests. Results: (1) Following intervention, sixty seven genes were up-regulated and 13 genes were down-regulated in the folic acid group, while 21 genes were up-regulated and none were down-regulated in the placebo group (P<0.05, adjusted for multiple testing). (2) Thirty six genes were up-regulated and 18 genes were down-regulated in the folic acid group when compared with placebo, but none of these were statistically significant after adjustment for multiple testing. These genes are involved in multiple pathways, including cell cycle, signal transduction, cell differentiation, transport, cell division, cell motility, protein transport and immune response. There were no genes involved in 1-carbon metabolism that were altered in expression, although several genes involved in neoplasia were up-regulated. Conclusions: These results indicate that while folic acid can modify gene expression, it is difficult to separate its effects from the natural variability in gene expression in the colon.

Project description:The fertility of dairy cows is challenged during early lactation and better nutritional strategies need to be developed to address this issue. Combined supplementation of folic acid and vitamin B12 improves energy metabolism in the dairy cow during early lactation. Therefore, the present study was undertaken to explore the effects of this supplement on gene expression in granulosa cells from the dominant follicle during the postpartum period. Multiparous Holstein cows received weekly intramuscular injection of 320 mg folic acid and 10 mg vitamin B12 (treated group) beginning 24 (SD 4) d before calving until 56 d after calving, whereas the control group received saline. The urea plasma concentration was significantly decreased during the pre-calving period, and the concentration of both folate and vitamin B12 were increased in treated animals. Milk production and dry matter intake were not significantly different between the two groups. Plasma concentrations of folates and vitamin B12 were increased in vitamin-treated animals. Daily dry matter intake was not significantly different between the 2 groups before (13.5 kg SE 0.5) and after (23.6 kg SE 0.9) calving. Average energy-corrected milk tended to be greater in vitamin-treated cows, 39.7 (SE 1.4) and 38.1 (SE 1.3) kg/d for treated and control cows, respectively. After calving, average plasma concentration of BHBA tended to be lower in cows injected with the vitamin supplement, 0.47 (SE 0.04) vs. 0.55 (SE 0.03) for treated and control cows, respectively. The ovarian follicle ? 12 mm in diameter was collected by ovarian pick-up after estrus synchronization. Recovered follicular fluid volumes were greater in the vitamin-treated group. A microarray platform was used to investigate the impact of treatment on gene expression of granulosa cells. Lower expression of genes involved in the cell cycle and higher expression of genes associated with granulosa cell differentiation prior to ovulation were observed. Selected candidate genes were analyzed by reverse transcription quantitative polymerase chain reaction. Although the effects of intramuscular injections of folic acid and vitamin B12 on lactational performance and metabolic status of animals were limited, Ingenuity Pathway Analysis of gene expression in granulosa cells suggests a stimulation of cell differentiation in vitamin-treated cows, which may be the result of an increase in LH secretion. Two conditions experiment (Control and Treated). Granulosa cells from the 66h post second PGF2alpha injection. Biological replicates: 3 from each time point. Two technical replicates for each comparison (dye-swap).

Project description:The fertility of dairy cows is challenged during early lactation and better nutritional strategies need to be developed to address this issue. Combined supplementation of folic acid and vitamin B12 improves energy metabolism in the dairy cow during early lactation. Therefore, the present study was undertaken to explore the effects of this supplement on gene expression in granulosa cells from the dominant follicle during the postpartum period. Multiparous Holstein cows received weekly intramuscular injection of 320 mg folic acid and 10 mg vitamin B12 (treated group) beginning 24 (SD 4) d before calving until 56 d after calving, whereas the control group received saline. The urea plasma concentration was significantly decreased during the pre-calving period, and the concentration of both folate and vitamin B12 were increased in treated animals. Milk production and dry matter intake were not significantly different between the two groups. Plasma concentrations of folates and vitamin B12 were increased in vitamin-treated animals. Daily dry matter intake was not significantly different between the 2 groups before (13.5 kg SE 0.5) and after (23.6 kg SE 0.9) calving. Average energy-corrected milk tended to be greater in vitamin-treated cows, 39.7 (SE 1.4) and 38.1 (SE 1.3) kg/d for treated and control cows, respectively. After calving, average plasma concentration of BHBA tended to be lower in cows injected with the vitamin supplement, 0.47 (SE 0.04) vs. 0.55 (SE 0.03) for treated and control cows, respectively. The ovarian follicle ? 12 mm in diameter was collected by ovarian pick-up after estrus synchronization. Recovered follicular fluid volumes were greater in the vitamin-treated group. A microarray platform was used to investigate the impact of treatment on gene expression of granulosa cells. Lower expression of genes involved in the cell cycle and higher expression of genes associated with granulosa cell differentiation prior to ovulation were observed. Selected candidate genes were analyzed by reverse transcription quantitative polymerase chain reaction. Although the effects of intramuscular injections of folic acid and vitamin B12 on lactational performance and metabolic status of animals were limited, Ingenuity Pathway Analysis of gene expression in granulosa cells suggests a stimulation of cell differentiation in vitamin-treated cows, which may be the result of an increase in LH secretion.

Project description:This study has been designed to evaluate the possible therapeutic benefits of L-5-methyltetrahydrofolate (Metafolin), vitamin B12, creatine and betaine in children with Angelman Syndrome (AS). This study is based on the hypotheses 1) that dietary manipulation may increase global DNA methylation; 2) that increased methylation of the paternal chromosome in AS participants may increase expression of the Angelman gene causing clinical benefit; and 3) that dietary interventions with Metafolin in conjunction with creatine, betaine, and vitamin B12 would represent little risk, but some chance for benefit. The dietary regimen is felt to be quite benign and safe. The clinical response will be measured by recording: changes in seizure activity, changes in communication skills, changes in developmental skills and changes in behavioral patterns as indicated by formal developmental assessments and clinical evaluations. We will assess the progress of the participants by monitoring their changes from baseline throughout their participation in the study and measure their improvement in particular in the developmental parameters. As a secondary aim, we plan to measure the biochemical response to these compounds by obtaining levels of homocysteine, methionine, S-adenosyl-methionine (SAM), and S-adenosyl-homocysteine (SAH). The molecular response will be measured by global DNA methylation analysis. As an exploratory aim, we hope to use control data we have previously obtained from a double blind placebo-controlled trial done in the past using betaine and folic acid to compare the development of those children who have and those who have not received medications. More specifically, we wish to compare differences in the rate of development for those children who have never received study medications (from the first trial) with those who have received medications from the present trial. Developmental parameters used in the previous trial will be consistent with those used in the present trial in order to permit these comparisons. The previous trial was conducted at Baylor College of Medicine, Rady San Diego Children's Hospital and Boston Children's Hospital whereas a group of AS participants received folic acid and betaine or placebo in a randomized double-blind basis. All the participants for the study will include patients who have a documented molecular diagnosis of AS. The participants will be seen at Baylor College of Medicine, Rady Children's Hospital of San Diego, Boston Children's Hospital and the Greenwood Genetics Center at 0 months and at 12 months for follow-up. Clinical and relevant historical data will be collected during the clinical visit and examination and also by reviewing medical and laboratory records. This information will then be entered into a HIPAA compliant clinical research database.

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The effects of long-term daily folic acid and vitamin B12 supplementation on genome-wide DNA methylation in elderly subjects

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