Folic Acid: A member of the vitamin B family that stimulates the hematopoietic system. It is present in the liver and kidney and is found in mushrooms, spinach, yeast, green leaves, and grasses (POACEAE). Folic acid is used in the treatment and prevention of folate deficiencies and megaloblastic anemia.Folic Acid Deficiency: A nutritional condition produced by a deficiency of FOLIC ACID in the diet. Many plant and animal tissues contain folic acid, abundant in green leafy vegetables, yeast, liver, and mushrooms but destroyed by long-term cooking. Alcohol interferes with its intermediate metabolism and absorption. Folic acid deficiency may develop in long-term anticonvulsant therapy or with use of oral contraceptives. This deficiency causes anemia, macrocytic anemia, and megaloblastic anemia. It is indistinguishable from vitamin B 12 deficiency in peripheral blood and bone marrow findings, but the neurologic lesions seen in B 12 deficiency do not occur. (Merck Manual, 16th ed)Neural Tube Defects: Congenital malformations of the central nervous system and adjacent structures related to defective neural tube closure during the first trimester of pregnancy generally occurring between days 18-29 of gestation. Ectodermal and mesodermal malformations (mainly involving the skull and vertebrae) may occur as a result of defects of neural tube closure. (From Joynt, Clinical Neurology, 1992, Ch55, pp31-41)Tetrahydrofolates: Compounds based on 5,6,7,8-tetrahydrofolate.Homocysteine: A thiol-containing amino acid formed by a demethylation of METHIONINE.Food, Fortified: Any food that has been supplemented with essential nutrients either in quantities that are greater than those present normally, or which are not present in the food normally. Fortified food includes also food to which various nutrients have been added to compensate for those removed by refinement or processing. (From Segen, Dictionary of Modern Medicine, 1992)Dietary Supplements: Products in capsule, tablet or liquid form that provide dietary ingredients, and that are intended to be taken by mouth to increase the intake of nutrients. Dietary supplements can include macronutrients, such as proteins, carbohydrates, and fats; and/or MICRONUTRIENTS, such as VITAMINS; MINERALS; and PHYTOCHEMICALS.Vitamin B 12: A cobalt-containing coordination compound produced by intestinal micro-organisms and found also in soil and water. Higher plants do not concentrate vitamin B 12 from the soil and so are a poor source of the substance as compared with animal tissues. INTRINSIC FACTOR is important for the assimilation of vitamin B 12.Vitamin B Complex: A group of water-soluble vitamins, some of which are COENZYMES.Folic Acid Antagonists: Inhibitors of the enzyme, dihydrofolate reductase (TETRAHYDROFOLATE DEHYDROGENASE), which converts dihydrofolate (FH2) to tetrahydrofolate (FH4). They are frequently used in cancer chemotherapy. (From AMA, Drug Evaluations Annual, 1994, p2033)Preconception Care: An organized and comprehensive program of health care that identifies and reduces a woman's reproductive risks before conception through risk assessment, health promotion, and interventions. Preconception care programs may be designed to include the male partner in providing counseling and educational information in preparation for fatherhood, such as genetic counseling and testing, financial and family planning, etc. This concept is different from PRENATAL CARE, which occurs during pregnancy.Folate Receptors, GPI-Anchored: Cell surface receptors that bind to and transport FOLIC ACID, 5-methyltetrahydrofolate, and a variety of folic acid derivatives. The receptors are essential for normal NEURAL TUBE development and transport folic acid via receptor-mediated endocytosis.Hyperhomocysteinemia: Condition in which the plasma levels of homocysteine and related metabolites are elevated (>13.9 µmol/l). Hyperhomocysteinemia can be familial or acquired. Development of the acquired hyperhomocysteinemia is mostly associated with vitamins B and/or folate deficiency (e.g., PERNICIOUS ANEMIA, vitamin malabsorption). Familial hyperhomocysteinemia often results in a more severe elevation of total homocysteine and excretion into the urine, resulting in HOMOCYSTINURIA. Hyperhomocysteinemia is a risk factor for cardiovascular and neurodegenerative diseases, osteoporotic fractures and complications during pregnancy.Anemia, Macrocytic: Anemia characterized by larger than normal erythrocytes, increased mean corpuscular volume (MCV) and increased mean corpuscular hemoglobin (MCH).Hematinics: Agents which improve the quality of the blood, increasing the hemoglobin level and the number of erythrocytes. They are used in the treatment of anemias.Vitamin B 6: VITAMIN B 6 refers to several PICOLINES (especially PYRIDOXINE; PYRIDOXAL; & PYRIDOXAMINE) that are efficiently converted by the body to PYRIDOXAL PHOSPHATE which is a coenzyme for synthesis of amino acids, neurotransmitters (serotonin, norepinephrine), sphingolipids, and aminolevulinic acid. During transamination of amino acids, pyridoxal phosphate is transiently converted into PYRIDOXAMINE phosphate. Although pyridoxine and Vitamin B 6 are still frequently used as synonyms, especially by medical researchers, this practice is erroneous and sometimes misleading (EE Snell; Ann NY Acad Sci, vol 585 pg 1, 1990). Most of vitamin B6 is eventually degraded to PYRIDOXIC ACID and excreted in the urine.Pteroylpolyglutamic Acids: Derivatives of folic acid (pteroylglutamic acid). In gamma-glutamyl linkage they are found in many tissues. They are converted to folic acid by the action of pteroylpolyglutamate hydrolase or synthesized from folic acid by the action of folate polyglutamate synthetase. Synthetic pteroylpolyglutamic acids, which are in alpha-glutamyl linkage, are active in bacterial growth assays.Vitamin B 12 Deficiency: A nutritional condition produced by a deficiency of VITAMIN B 12 in the diet, characterized by megaloblastic anemia. Since vitamin B 12 is not present in plants, humans have obtained their supply from animal products, from multivitamin supplements in the form of pills, and as additives to food preparations. A wide variety of neuropsychiatric abnormalities is also seen in vitamin B 12 deficiency and appears to be due to an undefined defect involving myelin synthesis. (From Cecil Textbook of Medicine, 19th ed, p848)Folic Acid Transporters: Proteins involved in the transport of FOLIC ACID and folate derivatives across the CELLULAR MEMBRANE.Pregnancy: The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.Bread: Baked food product made of flour or meal that is moistened, kneaded, and sometimes fermented. A major food since prehistoric times, it has been made in various forms using a variety of ingredients and methods.Vitamins: Organic substances that are required in small amounts for maintenance and growth, but which cannot be manufactured by the human body.Prenatal Care: Care provided the pregnant woman in order to prevent complications, and decrease the incidence of maternal and prenatal mortality.Flour: Ground up seed of WHEAT.Folate Receptor 1: A subtype of GPI-anchored folate receptors that is expressed in tissues of epithelial origin. This protein is also identified as an ovarian-tumor-specific antigen.Methylenetetrahydrofolate Reductase (NADPH2): A flavoprotein amine oxidoreductase that catalyzes the reversible conversion of 5-methyltetrahydrofolate to 5,10-methylenetetrahydrofolate. This enzyme was formerly classified as EC 1.1.1.171.Prenatal Nutritional Physiological Phenomena: Nutrition of FEMALE during PREGNANCY.Formyltetrahydrofolates: Tetrahydrofolates which are substituted by a formyl group at either the nitrogen atom in the 5 position or the nitrogen atom in the 10 position. N(5)-Formyltetrahydrofolate is leukovorin (citrovorum factor) while N(10)-formyltetrahydrofolate is an active coenzyme which functions as a carrier of the formyl group in a number of enzymatic reactions.Spinal Dysraphism: Congenital defects of closure of one or more vertebral arches, which may be associated with malformations of the spinal cord, nerve roots, congenital fibrous bands, lipomas, and congenital cysts. These malformations range from mild (e.g., SPINA BIFIDA OCCULTA) to severe, including rachischisis where there is complete failure of neural tube and spinal cord fusion, resulting in exposure of the spinal cord at the surface. Spinal dysraphism includes all forms of spina bifida. The open form is called SPINA BIFIDA CYSTICA and the closed form is SPINA BIFIDA OCCULTA. (From Joynt, Clinical Neurology, 1992, Ch55, p34)Aminopterin: A folic acid derivative used as a rodenticide that has been shown to be teratogenic.Double-Blind Method: A method of studying a drug or procedure in which both the subjects and investigators are kept unaware of who is actually getting which specific treatment.Reduced Folate Carrier Protein: A ubiquitously expressed folic acid transporter that functions via an antiporter mechanism which is coupled to the transport of organic phosphates.Pterins: Compounds based on 2-amino-4-hydroxypteridine.FIGLU Test: A urine test for formiminoglutamic acid, an intermediate metabolite in L-histidine catabolism in the conversion of L-histidine to L-glutamic acid. It may be an indicator of vitamin B12 or folic acid deficiency or liver disease.Pyridoxine: The 4-methanol form of VITAMIN B 6 which is converted to PYRIDOXAL PHOSPHATE which is a coenzyme for synthesis of amino acids, neurotransmitters (serotonin, norepinephrine), sphingolipids, aminolevulinic acid. Although pyridoxine and Vitamin B 6 are still frequently used as synonyms, especially by medical researchers, this practice is erroneous and sometimes misleading (EE Snell; Ann NY Acad Sci, vol 585 pg 1, 1990).Cereals: Seeds from grasses (POACEAE) which are important in the diet.Micronutrients: Essential dietary elements or organic compounds that are required in only small quantities for normal physiologic processes to occur.Diet: Regular course of eating and drinking adopted by a person or animal.Methotrexate: An antineoplastic antimetabolite with immunosuppressant properties. It is an inhibitor of TETRAHYDROFOLATE DEHYDROGENASE and prevents the formation of tetrahydrofolate, necessary for synthesis of thymidylate, an essential component of DNA.Anencephaly: A malformation of the nervous system caused by failure of the anterior neuropore to close. Infants are born with intact spinal cords, cerebellums, and brainstems, but lack formation of neural structures above this level. The skull is only partially formed but the eyes are usually normal. This condition may be associated with folate deficiency. Affected infants are only capable of primitive (brain stem) reflexes and usually do not survive for more than two weeks. (From Menkes, Textbook of Child Neurology, 5th ed, p247)Nutritional Requirements: The amounts of various substances in food needed by an organism to sustain healthy life.HomocystineMethylmalonic Acid: A malonic acid derivative which is a vital intermediate in the metabolism of fat and protein. Abnormalities in methylmalonic acid metabolism lead to methylmalonic aciduria. This metabolic disease is attributed to a block in the enzymatic conversion of methylmalonyl CoA to succinyl CoA.Nutrition Policy: Guidelines and objectives pertaining to food supply and nutrition including recommendations for healthy diet.4-Aminobenzoic Acid: An aminobenzoic acid isomer that combines with pteridine and GLUTAMIC ACID to form FOLIC ACID. The fact that 4-aminobenzoic acid absorbs light throughout the UVB range has also resulted in its use as an ingredient in SUNSCREENS.Riboflavin: Nutritional factor found in milk, eggs, malted barley, liver, kidney, heart, and leafy vegetables. The richest natural source is yeast. It occurs in the free form only in the retina of the eye, in whey, and in urine; its principal forms in tissues and cells are as FLAVIN MONONUCLEOTIDE and FLAVIN-ADENINE DINUCLEOTIDE.Biological Availability: The extent to which the active ingredient of a drug dosage form becomes available at the site of drug action or in a biological medium believed to reflect accessibility to a site of action.Erythrocytes: Red blood cells. Mature erythrocytes are non-nucleated, biconcave disks containing HEMOGLOBIN whose function is to transport OXYGEN.Nutritional Status: State of the body in relation to the consumption and utilization of nutrients.Glutamates: Derivatives of GLUTAMIC ACID. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain the 2-aminopentanedioic acid structure.Maternal Nutritional Physiological Phenomena: Nutrition of a mother which affects the health of the FETUS and INFANT as well as herself.Cleft Palate: Congenital fissure of the soft and/or hard palate, due to faulty fusion.Anemia, Megaloblastic: A disorder characterized by the presence of ANEMIA, abnormally large red blood cells (megalocytes or macrocytes), and MEGALOBLASTS.Pregnancy Complications, Hematologic: The co-occurrence of pregnancy and a blood disease (HEMATOLOGIC DISEASES) which involves BLOOD CELLS or COAGULATION FACTORS. The hematologic disease may precede or follow FERTILIZATION and it may or may not have a deleterious effect on the pregnant woman or FETUS.Methionine: A sulfur-containing essential L-amino acid that is important in many body functions.Vitamin B Deficiency: A condition due to deficiency in any member of the VITAMIN B COMPLEX. These B vitamins are water-soluble and must be obtained from the diet because they are easily lost in the urine. Unlike the lipid-soluble vitamins, they cannot be stored in the body fat.Placebos: Any dummy medication or treatment. Although placebos originally were medicinal preparations having no specific pharmacological activity against a targeted condition, the concept has been extended to include treatments or procedures, especially those administered to control groups in clinical trials in order to provide baseline measurements for the experimental protocol.Iron: A metallic element with atomic symbol Fe, atomic number 26, and atomic weight 55.85. It is an essential constituent of HEMOGLOBINS; CYTOCHROMES; and IRON-BINDING PROTEINS. It plays a role in cellular redox reactions and in the transport of OXYGEN.Anemia, Iron-Deficiency: Anemia characterized by decreased or absent iron stores, low serum iron concentration, low transferrin saturation, and low hemoglobin concentration or hematocrit value. The erythrocytes are hypochromic and microcytic and the iron binding capacity is increased.Oxidoreductases Acting on CH-NH Group Donors: Enzymes catalyzing the dehydrogenation of secondary amines, introducing a C=N double bond as the primary reaction. In some cases this is later hydrolyzed.Anemia, Pernicious: A megaloblastic anemia occurring in children but more commonly in later life, characterized by histamine-fast achlorhydria, in which the laboratory and clinical manifestations are based on malabsorption of vitamin B 12 due to a failure of the gastric mucosa to secrete adequate and potent intrinsic factor. (Dorland, 27th ed)gamma-Glutamyl Hydrolase: Catalyzes the hydrolysis of pteroylpolyglutamic acids in gamma linkage to pterolylmonoglutamic acid and free glutamic acid. EC 3.4.19.9.Iron, Dietary: Iron or iron compounds used in foods or as food. Dietary iron is important in oxygen transport and the synthesis of the iron-porphyrin proteins hemoglobin, myoglobin, cytochromes, and cytochrome oxidase. Insufficient amounts of dietary iron can lead to iron-deficiency anemia.Cleft Lip: Congenital defect in the upper lip where the maxillary prominence fails to merge with the merged medial nasal prominences. It is thought to be caused by faulty migration of the mesoderm in the head region.Pregnancy Complications: Conditions or pathological processes associated with pregnancy. They can occur during or after pregnancy, and range from minor discomforts to serious diseases that require medical interventions. They include diseases in pregnant females, and pregnancies in females with diseases.Administration, Oral: The giving of drugs, chemicals, or other substances by mouth.Infant, Newborn: An infant during the first month after birth.KB Cells: This line KB is now known to be a subline of the ubiquitous KERATIN-forming tumor cell line HeLa. It was originally thought to be derived from an epidermal carcinoma of the mouth, but was subsequently found, based on isoenzyme analysis, HeLa marker chromosomes, and DNA fingerprinting, to have been established via contamination by HELA CELLS. The cells are positive for keratin by immunoperoxidase staining. KB cells have been reported to contain human papillomavirus18 (HPV-18) sequences.IrelandIntestinal Absorption: Uptake of substances through the lining of the INTESTINES.Trimetrexate: A nonclassical folic acid inhibitor through its inhibition of the enzyme dihydrofolate reductase. It is being tested for efficacy as an antineoplastic agent and as an antiparasitic agent against PNEUMOCYSTIS PNEUMONIA in AIDS patients. Myelosuppression is its dose-limiting toxic effect.Tetrahydrofolate Dehydrogenase: An enzyme of the oxidoreductase class that catalyzes the reaction 7,8-dihyrofolate and NADPH to yield 5,6,7,8-tetrahydrofolate and NADPH+, producing reduced folate for amino acid metabolism, purine ring synthesis, and the formation of deoxythymidine monophosphate. Methotrexate and other folic acid antagonists used as chemotherapeutic drugs act by inhibiting this enzyme. (Dorland, 27th ed) EC 1.5.1.3.Dose-Response Relationship, Drug: The relationship between the dose of an administered drug and the response of the organism to the drug.Lactobacillus casei: A rod-shaped bacterium isolated from milk and cheese, dairy products and dairy environments, sour dough, cow dung, silage, and human mouth, human intestinal contents and stools, and the human vagina.NepalMethylenetetrahydrofolate Dehydrogenase (NAD+)Leucovorin: The active metabolite of FOLIC ACID. Leucovorin is used principally as an antidote to FOLIC ACID ANTAGONISTS.Betaine: A naturally occurring compound that has been of interest for its role in osmoregulation. As a drug, betaine hydrochloride has been used as a source of hydrochloric acid in the treatment of hypochlorhydria. Betaine has also been used in the treatment of liver disorders, for hyperkalemia, for homocystinuria, and for gastrointestinal disturbances. (From Martindale, The Extra Pharmacopoeia, 30th ed, p1341)Congenital Abnormalities: Malformations of organs or body parts during development in utero.Mouth Abnormalities: Congenital absence of or defects in structures of the mouth.

Thiamine deficiency is prevalent in a selected group of urban Indonesian elderly people. (1/4015)

This cross-sectional study involved 204 elderly individuals (93 males and 111 females). Subjects were randomly recruited using a list on which all 60-75 y-old-people living in seven sub-villages in Jakarta were included. The usual food intake was estimated using semiquantitative food frequency questionnaires. Hemoglobin, plasma retinol, vitamin B-12, red blood cell folate and the percentage stimulation of erythrocyte transketolase (ETK), as an indicator of thiamine status, were analyzed. Median energy intake was below the assessed requirement. More than 75% of the subjects had iron and thiamine intakes of approximately 2/3 of the recommended daily intake, and 20.2% of the study population had folate intake of approximately 2/3 of the recommended daily intake. Intakes of vitamins A and B-12 were adequate. Biochemical assessments demonstrated that 36.6% of the subjects had low thiamine levels (ETK stimulation > 25%). The elderly men tended to have lower thiamine levels than the elderly women. The overall prevalence of anemia was 28.9%, and the elderly women were affected more than the elderly men. Low biochemical status of vitamins A, B-12 and RBC folate was found in 5.4%, 8.8 % and 2.9% of the subjects, respectively. Dietary intakes of thiamine and folate were associated with ETK stimulation and plasma vitamin B-12 concentration (r = 0.176, P = 0.012 and r = 0.77, P = 0.001), respectively. Results of this study suggest that anemia, thiamine and possibly vitamin B-12 deficiency are prevalent in the elderly living in Indonesia. Clearly, micronutrient supplementation may be beneficial for the Indonesian elderly population living in underprivileged areas.  (+info)

Plasma total homocysteine and cysteine in relation to glomerular filtration rate in diabetes mellitus. (2/4015)

BACKGROUND: The plasma concentrations of total homocysteine (tHcy) and total cysteine (tCys) are determined by intracellular metabolism and by renal plasma clearance, and we hypothesized that glomerular filtration is a major determinant of plasma tHcy and tCys. We studied the relationships between the glomerular filtration rate (GFR) and plasma tHcy and tCys in populations of diabetic patients with particularly wide ranges of GFR. METHODS: We measured GFR, urine albumin excretion rate (UAER), plasma tHcy, tCys, methionine, vitamin B12, folate, C-peptide, and routine parameters in 50 insulin-dependent diabetes mellitus (IDDM) and 30 non-insulin-dependent diabetes mellitus (NIDDM) patients. All patients underwent intensive insulin treatment and had a serum creatinine concentration below 115 micromol/liter. RESULTS: Mean plasma tHcy in diabetic patients (0.1 micromol/liter) was lower than in normal persons (11.1 micromol/liter, P = 0.0014). Mean plasma tCys in diabetic patients (266.1 micromol/liter) was also lower than in normal persons (281.9 micromol/liter, P = 0.0005). Seventy-three percent of the diabetic patients had relative hyperfiltration. Plasma tHcy and tCys were closely and independently associated with GFR, serum folate, and serum B12. However, plasma tHcy was not independently associated with any of the 22 other variables tested, including age, serum creatinine concentration, UAER, total daily insulin dose, and glycemic control. CONCLUSIONS: Glomerular filtration rate is an independent determinant of plasma tHcy and tCys concentrations, and GFR is rate limiting for renal clearance of both homocysteine and cysteine in diabetic patients without overt nephropathy. Declining GFR explains the age-related increase in plasma tHcy, and hyperfiltration explains the lower than normal mean plasma tHcy and tCys concentrations in populations of diabetic patients.  (+info)

Effect of MTHFR 677C>T on plasma total homocysteine levels in renal graft recipients. (3/4015)

BACKGROUND: Hyperhomocysteinemia is an established, independent risk factor for vascular disease morbidity and mortality. The 5,10-methylenetetrahydrofolate reductase (MTHFR) gene polymorphism C677T has been shown to result in increased total homocysteine concentrations on the basis of low folate levels caused by a decreased enzyme activity. The effect of this polymorphism on total homocysteine and folate plasma levels in renal transplant patients is unknown. METHODS: We screened 636 kidney graft recipients for the presence of the MTHFR C677T gene polymorphism. The major determinants of total homocysteine and folate plasma concentrations of 63 patients, who were identified to be homozygous for this gene polymorphism compared with heterozygotes (N = 63), and patients with wild-type alleles (N = 63), who were matched for sex, age, glomerular filtration rate (GFR), and body mass index, were identified by analysis of covariance. The variables included sex, age, GFR, body mass index, time since transplantation, folate and vitamin B12 levels, the use of azathioprine, and the MTHFR genotype. To investigate the impact of the kidney donor MTHFR genotype on total homocysteine and folate plasma concentrations, a similar model was applied in 111 kidney graft recipients with stable graft function, in whom the kidney donor C677T MTHFR gene polymorphism was determined. RESULTS: The allele frequency of the C677T polymorphism in the MTHFR gene was 0.313 in the whole study population [wild-type (CC), 301; heterozygous (CT), 272; and homozygous mutant (TT), 63 patients, respectively] and showed no difference in the patient subgroups with various renal diseases. The MTHFR C677T gene polymorphism significantly influenced total homocysteine and folate plasma concentrations in renal transplant recipients (P = 0.0009 and P = 0.0002, respectively). Furthermore, a significant influence of the GFR (P = 0.0001), folate levels (P = 0.0001), age (P = 0.0001), body mass index (P = 0.0001), gender (P = 0.0005), and vitamin B12 levels (P = 0.004) on total homocysteine concentrations was observed. The donor MTHFR gene polymorphism had no influence on total homocysteine and folate levels. Geometric mean total homocysteine levels in patients homozygous for the mutant MTHFR allele were 18.6 micromol/liter compared with 14.6 micromol/liter and 14.9 micromol/liter in patients heterozygous for the MTHFR gene polymorphism and those with wild-type alleles (P < 0.05 for TT vs. CT and CC). Geometric mean folate levels were lower in CT and TT patients (11.2 and 10.2 nmol/liter) compared with CC patients (13.6 nmol/liter, P < 0.05 vs. CT and TT). CONCLUSIONS: This study demonstrates that homozygosity for the C677T polymorphism in the MTHFR gene significantly increases total homocysteine concentrations and lowers folate levels in kidney graft recipients, even in patients with excellent renal function (GFR more than median). These findings have important implications for risk evaluation and vitamin intervention therapy in these patients who carry an increased risk for the development of cardiovascular disease.  (+info)

Endothelial dysfunction by acute hyperhomocyst(e)inaemia: restoration by folic acid. (4/4015)

Recent evidence demonstrates that hyperhomocyst(e)inaemia is a novel risk factor for cardiovascular diseases. In patients with chronic hyperhomocyst(e)inaemia, endothelial function is impaired. However, whether hyperhomocyst(e)inaemia per se is a cause or an epiphenomenon of endothelial dysfunction remains unknown. In this study, we examined the effects of methionine-induced acute hyperhomocyst(e)inaemia on human endothelial function. In healthy volunteers we administered methionine (0.1 g/kg body weight, per os), a substrate of homocyst(e)ine, with or without folic acid (20 mg, per os) and examined flow-mediated vasodilatation of the brachial artery by high-resolution ultrasonography as a non-invasive measure of endothelial function. We also measured plasma levels of homocyst(e)ine before and 3, 8 and 24 h after methionine loading. Methionine administration increased plasma levels of homocyst(e)ine by four times the basal level at 8 h (P<0.0001, ANOVA). The plasma levels returned to baseline at 24 h. Flow-mediated vasodilatation was significantly decreased to half of the baseline value at 8 h and returned to baseline at 24 h (P<0.0001, ANOVA), whereas endothelium-independent vasodilatation by glyceryl trinitrate was not affected by the methionine loading. Co-administration of folic acid did not attenuate methionine-induced hyperhomocyst(e)inaemia but completely prevented endothelial dysfunction. Our results suggest that in humans a methionine-rich diet may acutely impair endothelial function, which can be prevented by folic acid supplementation.  (+info)

Influence of haemodialysis on plasma total homocysteine concentration. (5/4015)

BACKGROUND: The high prevalence of hyperhomocysteinaemia in uraemic patients is of interest because of the cardiovascular risk associated with increased plasma total homocysteine (tHcy) concentration. Treatment with folic acid lowers tHcy in haemodialysis patients, however, in most patients not to normohomocysteinaemic levels. With possible tHcy-lowering modifications in mind, we studied the influence of standard haemodialysis on tHcy. METHODS: In 56 folate-loaded haemodialysis patients, tHcy and parameters of dialysis adequacy were measured. In six patients, interdialytic curves of tHcy and serum creatinine concentrations were obtained and in five patients, the amount of homocysteine (Hcy) in dialysate was determined. RESULTS: tHcy (21.8+/-14.4 micromol/l) correlated significantly with Kt/V (r=0.32, P<0.05), total Kt/V (r=0.29, P<0.05), nPCR (r=0.30, P<0.05) and serum concentrations of albumin (r=0.28, P<0.05) and cobalamines (r=-0.27, P<0.05). In a multiple linear regression analysis, only serum albumin concentrations significantly predicted tHcy (r=0.34, P < 0.05). During dialysis, tHcy decreased by 28% and remained constant for at least 8 h after treatment. The amount of Hcy recovered in dialysate was 63 micromol (12-158 micromol). There was no difference in tHcy between those who had residual renal function and those who had not. CONCLUSIONS: The direct relationship between tHcy and Kt/V seemed to be mediated by the serum albumin concentration. The shape of the interdialytic tHcy curve suggested facilitated Hcy removal for at least 8 h after dialysis possibly due to reduced levels of inhibitory activities against relevant enzyme(s). The dialysed amount of Hcy did not seem to contribute significantly to Hcy removal. Thus, modifications of standard dialytic regimens are not likely to be effective from a tHcy-lowering point of view whereas convective procedures such as haemofiltration or haemodiafiltration might be more effective.  (+info)

An estimation of the requirement for folic acid in gestating sows: the metabolic utilization of folates as a criterion of measurement. (6/4015)

Sows at their second parity were randomly distributed in five groups of seven animals each to determine the dietary concentration of folic acid that optimizes the metabolic utilization of the vitamin during gestation. The groups differed by dietary supplement of folic acid: 0, 5, 10, 15, or 20 ppm. Sows were fed 2.5 kg of diet each day. The response of serum folates and folate binding capacity to treatments and the excretion of urinary folates after an i.v. injection of folic acid were measured. The total daily excretion of urinary folates was corrected according to the response to one i.v. injection of saline on the day preceding the i.v. injection of folic acid. The decrease of total serum folates throughout gestation was less pronounced in the groups fed 15 and 20 ppm of dietary folic acid (supplement x period interaction, P<.06) than it was in the other three treatments. The proportion of i.v. folic acid not recovered in sow urine (injected - excreted) decreased as the amount of dietary folic acid increased to reach a minimum, which differed according to the period (supplement x period interaction, P<.02); it was 15 ppm during wk 1 of gestation and 10 ppm for the other periods studied. The unrecovered folates increased over a dietary concentration of 15 ppm. These minimum values correspond to the most appropriate feed concentration that covered the whole body utilization (tissue and cell metabolism, catabolism, and storage) of folates by the sows and could be interpreted as a reliable index of the requirement.  (+info)

MTHFR polymorphism, methyl-replete diets and the risk of colorectal carcinoma and adenoma among U.S. men and women: an example of gene-environment interactions in colorectal tumorigenesis. (7/4015)

Our studies on interactions of a folate-metabolizing gene polymorphism and dietary intake in colorectal tumorigenesis demonstrate the potential importance of studying interactions between genotype and environmental exposure in relation to cancer risk. We observed an inverse association of a polymorphism (667C --> T, ala --> val) in the methylenetetrahydrofolate reductase (MTHFR) gene with colorectal cancer but not with colorectal adenomas. The inverse association of methionine and adverse association of alcohol with colorectal cancer were stronger among val/val individuals. These interactions were not present in studies of colorectal adenomas. Our studies illustrate that studying gene-environment interactions in relation to cancer can be of importance in clarifying cancer etiology as well as pointing to preventive dietary modifications.  (+info)

Hyperhomocyst(e)inaemia in children with chronic renal failure. (8/4015)

BACKGROUND: Hyperhomocyst(e)inaemia has been identified as a significant risk factor for the occurrence of atherosclerosis in adults with chronic renal failure. Because of its presumed direct toxic effect on the vascular wall, long-standing hyperhomocyst(e)inaemia in children with chronic renal failure might have an important influence on their risk of future development of atherosclerosis. Hitherto no data on hyperhomocyst(e)inaemia in children with renal failure have been published. METHODS: We investigated 16 children with chronic renal failure on conservative management, 12 children on haemodialysis and 17 children with a renal transplant. Age-matched controls were used for comparison. Plasma homocyst(e)ine levels after an overnight fast were determined by HPLC. Glomerular filtration rate was estimated by the Schwartz formula. RESULTS: Mean plasma homocyst(e)ine levels were 12.6 +/- 5.2 micromol/l in the conservatively managed group, 22.2 +/- 13.5 micromol/l in the haemodialysed group, 14.2 +/- 2.1 micromol/l in transplanted children with an estimated GFR > 60 ml/min/1.73 m2 and 17.5 +/- 5.1 micromol/l in transplanted children with a lower estimated GFR. In all groups homocyst(e)ine levels were significantly elevated as compared to controls. Homocyst(e)ine levels were significantly correlated with age and negatively correlated with estimated GFR and serum folate levels. CONCLUSIONS: Hyperhomocyst(e)inaemia is a feature of chronic renal failure in children as well as in adults. Elevated homocyst(e)ine levels can already be demonstrated in children with renal failure before end-stage renal disease has developed and persist after renal transplantation. Whether treatment of hyperhomocyst(e)inaemia in children with renal failure decreases the risk for future atherosclerosis remains to be proven.  (+info)

  • Because a lot of important brain growth happens in the first weeks before women know they're pregnant, it's recommended that all women of childbearing age (15-45) take folic acid, even if they don't plan on becoming pregnant. (achn.net)
  • In 1991 the Medical Research Council Vitamin Study Group and in 1992 the Hungarian randomised clinical trial have shown conclusively that the risk of neural tube defects can be reduced substantially by taking folic acid during the peri-conceptional period. (clinicaltrials.gov)
  • At present there is enough evidence to support the hypothesis that folic acid supplementation can reduce the risk of all congenital malformations or of a specific and selected group of them, namely: neural tube defects, oral clefts, cardiac defects, urinary tract anomalies except hypospadias, limb reduction defects, omphalocele, anal atresia and trisomy 21. (clinicaltrials.gov)
  • The hypothesis that a higher intake of folic acid is related to an higher risk reduction of neural tube defects and of other congenital malformations is the main rationale for the present study. (clinicaltrials.gov)
  • It is actually very important for expectant mothers to take 400 micrograms of folic acid daily to ensure the fetus does not have any neural tube defects. (growingyourbaby.com)
  • The Food and Drug Administration mandated that by 1998, all enriched cereal grain products (ECGP) be fortified with folic acid in order to prevent the occurrence of neural tube defects. (cdc.gov)
  • A diet that's high in folic acid can prevent certain types of anemia, and reduce neural tube defects such as spina bifida. (womensview.com)
  • (in.gov)
  • Folic acid has been linked to the development of a protective covering called the neural tube in a fetus. (blogspot.com)
  • It's been well documented that folic acid prevents NTDs (neural tube defects). (kimmaravich.com)
  • Importance: Presently, 81 countries mandate the fortification of grain products with folic acid to lessen the risk of neural tube defects in the developing fetus. (centerforautismresearch.com)
  • Prevention of neural tube defects: a cross-sectional study of the uptake of folic acid supplementation in nearly half a million women. (qmul.ac.uk)
  • If you're pregnant or even planning to get pregnant, taking folic acid will help prevent serious birth defects in your baby. (achn.net)
  • This study was a bit different than most which have been completed on folic acid and birth defects, which have included primarily middle - higher income families. (drfionand.com)
  • Unfortunately, fresh, healthy produce is much more expensive than processed foods.As a result of the widespread addition of folic acid to processed foods, it follows that those who eat more of these foods may have more unmetabolized folic acid in their bloodstreams. (drfionand.com)
  • The present study is a randomized, double-blind, controlled trial evaluating whether supplementation with folic acid at high dose (4 mg/day) reduces the overall risk of major congenital malformations in the population more than the standard recommended dose (0.4 mg/day). (clinicaltrials.gov)
  • Both sets of women were assigned to receive a daily folic acid dose of 10 milligrams for four weeks. (preventdisease.com)
  • Hoch and her co-workers said that further study is necessary to determine the lowest optimal dose of folic acid for athletic amenorrhea which offers the maximum benefit. (preventdisease.com)
  • Therefore very low dose folic acid, say 1.25 mg or one-fourth of a 5 mg tablet alone should be taken to see if it causes allergic reaction. (ndtv.com)
  • The Atherosclerosis and Folic Acid Supplementation Trial (ASFAST) aimed to establish whether high-dose folic acid would slow the progression of atherosclerosis and reduce cardiovascular events in patients with chronic renal failure (CRF). (monash.edu)
  • A half cup of dry roasted soybeans contains 44% of the daily recommended value of folic acid, helping you reach your quota for the day while providing a healthy dose of antioxidants. (womensview.com)
  • Additionally, these specialists educate women on the importance of consuming a daily dose of folic acid while pregnant or planning to become pregnant, as it can prevent spinal and brain congenital disabilities. (achn.net)
  • when you are ttc, doctors advice u to start folic acid 3 months prior. (babycenter.in)
  • There are no known side effects linked with large doses of folic acid. (rochester.edu)
  • I have folic acid allergy , I get rashes all over the body whenever I consume B-Complex, Folic Acid or Iron-folic acid tablets. (ndtv.com)
  • Like the other B vitamins, folic acid plays an important role in energy production. (rochester.edu)
  • Nutrients such as folic acid and other vitamins are commonly added to products we buy at the store such as bread and cereal-a process referred to as fortification. (emersonecologics.com)
  • There is a significant difference between folic acid (synthetic) and natural folate (found in high quality vitamins in the form of L-5-MTHF, or in foods like leafy green raw vegetables and fruit. (drfionand.com)
  • People with MTHFR and other mutations in folate metabolism genes do not effectively metabolize the synthetic folic acid that is found in certain vitamins and processed foods. (drfionand.com)
  • In recent years, researchers have begun to investigate whether folic acid supplements may also have other beneficial effects on the development of the brain and spinal cord in the foetus. (medicalxpress.com)
  • To explore whether kids born to women exposed to folic acid-fortified food sources have lower cancer risk, researchers looked at the incidence of childhood cancers in kids up to four years old during the time period before food was fortified with folic acid and after 1996 when the US Food and Drug Administration required that all enriched grain products be fortified with folic acid. (emersonecologics.com)
  • A half cup of chopped broccoli gives you 52 micrograms of folic acid, or about 13% of what the average person should consume per day. (womensview.com)
  • This study was comprised of lower income families, who often don't consume as much fresh fruit and vegetables (which contain natural bioavailable folates) and tend to consume more packaged and processed foods (containing synthetic folic acid) on the whole. (drfionand.com)
  • This study demonstrates the need to fortify flour and other cereal grain with folic acid in all countries of the world. (qmul.ac.uk)
  • At this time, the AHA doesn't recommend the use of folic acid or vitamin B supplements to reduce the risk for heart disease. (rochester.edu)
  • It should also be ascertained whether folic acid is associated with a reduced risk of other brain disorders in children," says Surén. (medicalxpress.com)
  • Diets rich in folic acid may also reduce your lifetime risk of developing Alzheimer's disease and several types of cancer. (womensview.com)
  • Recent studies indicate that folic acid may also reduce the risk of heart and limb defects. (in.gov)
  • Folic Acid may reduce the risk of Heart Attack: In the case of High Blood pressure Folic acid can reduce the risk of the Heart Attack. (careinfo.in)
  • Well, with all of the good that folic acid seems to afford a pregnant woman, it is not without risk for some people. (kimmaravich.com)
  • Unmetabolized folate in the bloodstream increases when synthetic folic acid is taken by those with MTHFR mutations, as they are unable to use it effectively.As such, the autism risk in this study may be increased by having MTHFR itself, and serum folate may be raised due to having the mutation. (drfionand.com)
  • So, another question - is it the folic acid, or is it the processed food consumption, or another factor associated with consuming more processed food which is associated with this risk of autism? (drfionand.com)
  • mean [SD] age, 13.3 [2.years).Conclusions and Relevance: The results of this study suggest an association between gestational exposure to fortification of grain products with folic acid and altered cortical development and, in turn, with reduction in the risk of psychosis in youths. (centerforautismresearch.com)
  • In those new mums with both folic acid and B12 overdoses, the risk of autism in their babies increased 17.6 times. (beforemybaby.com)
  • Folic Acid is also found naturally as folates in foods like beans, peanuts, orange juice, lentils and green vegetables like spinach and broccoli. (growingyourbaby.com)
  • but I will still advice you to include foods which are very rich in folic acid. (babycenter.in)
  • Many foods contain plenty of folic acid, but which ones contain the most? (womensview.com)
  • So at that point, "folic acid" became used to denote the fully oxidized chemical compound, not present in natural foods . (kimmaravich.com)
  • It is not entirely known how fortification of foods with folic acid may help prevent childhood cancers. (emersonecologics.com)
  • While folic acid has been added to many foods, such as cereal, bread, pasta and rice, it's hard to get the recommended amount from food alone. (achn.net)
  • In addition to taking a prenatal vitamin with folic acid, women can also eat foods that naturally contain folate for an extra boost. (achn.net)
  • Secondly, consider that synthetic folic acid is added to many processed foods - meaning that those who eat processed foods are exposed to much more on a daily basis. (drfionand.com)
  • The addition of synthetic folic acid to processed foods, pasta and bakery products is also potentially involved here. (drfionand.com)