1 853 117 CHOLINE, OTHER METHYL-DONORS AND EPIGENETICS. CHOLINE DIETARY INTAKE VARIES SUCH THAT MANY PEOPLE DO NOT ACHIEVE ADEQUATE INTAKES. DIET INTAKE OF CHOLINE CAN MODULATE METHYLATION BECAUSE, VIA BETAINE HOMOCYSTEINE METHYLTRANSFERASE (BHMT), THIS NUTRIENT (AND ITS METABOLITE, BETAINE) REGULATE THE CONCENTRATIONS OF S-ADENOSYLHOMOCYSTEINE AND S-ADENOSYLMETHIONINE. SOME OF THE EPIGENETIC MECHANISMS THAT MODIFY GENE EXPRESSION WITHOUT MODIFYING THE GENETIC CODE DEPEND ON THE METHYLATION OF DNA OR OF HISTONES; AND DIET AVAILABILITY OF CHOLINE AND OTHER METHYL-GROUP DONORS INFLUENCES BOTH OF THESE METHYLATIONS. EXAMPLES OF METHYL-DONOR MEDIATED EPIGENETIC EFFECTS INCLUDE THE CHANGES IN COAT COLOR AND BODY WEIGHT IN OFFSPRING WHEN PREGNANT AGOUTI MICE ARE FED HIGH CHOLINE, HIGH METHYL DIETS; THE CHANGES IN TAIL KINKING IN OFFSPRING WHEN PREGNANT AXIN(FU) MICE ARE FED HIGH CHOLINE, HIGH METHYL DIETS; THE CHANGES IN CDKN3 METHYLATION AND ALTERED BRAIN DEVELOPMENT THAT OCCURS IN OFFSPRING WHEN PREGNANT RODENTS ARE FED LOW CHOLINE DIETS. WHEN CHOLINE METABOLISM IS DISRUPTED BY DELETING THE GENE BHMT, DNA METHYLATION IS AFFECTED (ESPECIALLY IN A REGION OF CHROMOSOME 13), EXPRESSION OF SPECIFIC GENES IS SUPPRESSED, AND LIVER CANCERS DEVELOP. BETTER UNDERSTANDING OF HOW NUTRIENTS SUCH AS CHOLINE AND METHYL-DONORS INFLUENCE EPIGENETIC PROGRAMS HAS IMPORTANCE FOR OUR UNDERSTANDING OF NOT ONLY DEVELOPMENTAL ABNORMALITIES BUT ALSO FOR UNDERSTANDING THE ORIGINS OF CHRONIC DISEASES. 2017 2 4086 37 MATERNAL OBESITY DISRUPTS THE METHIONINE CYCLE IN BABOON PREGNANCY. MATERNAL INTAKE OF DIETARY METHYL-MICRONUTRIENTS (E.G. FOLATE, CHOLINE, BETAINE AND VITAMIN B-12) DURING PREGNANCY IS ESSENTIAL FOR NORMAL MATERNAL AND FETAL METHIONINE METABOLISM, AND IS CRITICAL FOR IMPORTANT METABOLIC PROCESSES INCLUDING THOSE INVOLVED IN DEVELOPMENTAL PROGRAMMING. MATERNAL OBESITY AND NUTRIENT EXCESS DURING PREGNANCY INFLUENCE DEVELOPMENTAL PROGRAMMING POTENTIALLY PREDISPOSING ADULT OFFSPRING TO A VARIETY OF CHRONIC HEALTH PROBLEMS. IN THE PRESENT STUDY, WE HYPOTHESIZED THAT MATERNAL OBESITY WOULD DYSREGULATE THE MATERNAL AND FETAL METHIONINE CYCLE. TO TEST THIS HYPOTHESIS, WE DEVELOPED A NULLIPAROUS BABOON OBESITY MODEL FED A HIGH FAT, HIGH ENERGY DIET (HF-HED) PRIOR TO AND DURING GESTATION, AND EXAMINED METHIONINE CYCLE BIOMARKERS (E.G., CIRCULATING CONCENTRATIONS OF HOMOCYSTEINE, METHIONINE, CHOLINE, BETAINE, KEY AMINO ACIDS, FOLATE, AND VITAMIN B-12). ANIMALS WERE GROUP HOUSED ALLOWING FULL PHYSICAL ACTIVITY AND SOCIAL INTERACTION. MATERNAL PREPREGNANCY PERCENT BODY FAT WAS 5% IN CONTROLS AND 19% IN HF-HED MOTHERS, WHILE FETAL WEIGHT WAS 16% LOWER IN OFFSPRING OF HF-HED MOTHERS AT TERM. MATERNAL AND FETAL HOMOCYSTEINE WERE HIGHER, WHILE MATERNAL AND FETAL VITAMIN B-12 AND BETAINE WERE LOWER IN THE HF-HED GROUP. ELEVATIONS IN CIRCULATING MATERNAL FOLATE WERE EVIDENT IN THE HF-HED GROUP INDICATING IMPAIRED FOLATE METABOLISM (METHYL-TRAP) AS A CONSEQUENCE OF MATERNAL VITAMIN B-12 DEPLETION. FINALLY, FETAL METHIONINE, GLYCINE, SERINE, AND TAURINE WERE LOWER IN THE HF-HED FETUSES. THESE DATA SHOW THAT MATERNAL OBESITY DISTURBS THE METHIONINE CYCLE IN PRIMATE PREGNANCY, PROVIDING A MECHANISM FOR THE EPIGENETIC CHANGES OBSERVED AMONG OBESE PREGNANT WOMEN AND SUGGESTING DIAGNOSTIC AND THERAPEUTIC OPPORTUNITIES IN HUMAN PREGNANCIES COMPLICATED BY OBESITY. 2015 3 1855 29 ELEVATION IN S-ADENOSYLHOMOCYSTEINE AND DNA HYPOMETHYLATION: POTENTIAL EPIGENETIC MECHANISM FOR HOMOCYSTEINE-RELATED PATHOLOGY. CHRONIC NUTRITIONAL DEFICIENCIES IN FOLATE, CHOLINE, METHIONINE, VITAMIN B-6 AND/OR VITAMIN B-12 CAN PERTURB THE COMPLEX REGULATORY NETWORK THAT MAINTAINS NORMAL ONE-CARBON METABOLISM AND HOMOCYSTEINE HOMEOSTASIS. GENETIC POLYMORPHISMS IN THESE PATHWAYS CAN ACT SYNERGISTICALLY WITH NUTRITIONAL DEFICIENCIES TO ACCELERATE METABOLIC PATHOLOGY ASSOCIATED WITH OCCLUSIVE HEART DISEASE, BIRTH DEFECTS AND DEMENTIA. A MAJOR UNANSWERED QUESTION IS WHETHER HOMOCYSTEINE IS CAUSALLY INVOLVED IN DISEASE PATHOGENESIS OR WHETHER HOMOCYSTEINEMIA IS SIMPLY A PASSIVE AND INDIRECT INDICATOR OF A MORE COMPLEX MECHANISM. S-ADENOSYLMETHIONINE AND S-ADENOSYLHOMOCYSTEINE (SAH), AS THE SUBSTRATE AND PRODUCT OF METHYLTRANSFERASE REACTIONS, ARE IMPORTANT METABOLIC INDICATORS OF CELLULAR METHYLATION STATUS. CHRONIC ELEVATION IN HOMOCYSTEINE LEVELS RESULTS IN PARALLEL INCREASES IN INTRACELLULAR SAH AND POTENT PRODUCT INHIBITION OF DNA METHYLTRANSFERASES. SAH-MEDIATED DNA HYPOMETHYLATION AND ASSOCIATED ALTERATIONS IN GENE EXPRESSION AND CHROMATIN STRUCTURE MAY PROVIDE NEW HYPOTHESES FOR PATHOGENESIS OF DISEASES RELATED TO HOMOCYSTEINEMIA. 2002 4 48 32 A CRUCIAL ROLE FOR MATERNAL DIETARY METHYL DONOR INTAKE IN EPIGENETIC PROGRAMMING AND FETAL GROWTH OUTCOMES. THE FETAL ORIGINS OF HEALTH AND DISEASE FRAMEWORK HAS IDENTIFIED EXTREMES IN FETAL GROWTH AND BIRTH WEIGHT AS FACTORS ASSOCIATED WITH THE LIFELONG GENERATION OF CHRONIC DISEASES SUCH AS OBESITY, DIABETES, CARDIOVASCULAR DISEASE, AND HYPERTENSION. MATERNAL NUTRITION PLAYS A CRITICAL ROLE IN FETAL AND PLACENTAL DEVELOPMENT, IN PART BY PROVIDING THE METHYL GROUPS REQUIRED TO ESTABLISH THE FETUS'S GENOME STRUCTURE AND FUNCTION, NOTABLY THROUGH DNA METHYLATION. THE GOAL OF THIS NARRATIVE REVIEW IS TO DESCRIBE THE ROLE OF MATERNAL DIETARY METHYL DONOR (METHIONINE, FOLATE, AND CHOLINE) AND COFACTOR (ZINC AND VITAMINS B2, B6, AND B12) INTAKE IN ONE-CARBON METABOLISM AND DNA METHYLATION IN THE FETUS AND PLACENTA, AS WELL AS THEIR IMPACTS ON FETAL GROWTH AND LIFELONG HEALTH OUTCOMES, WITH SPECIFIC EXAMPLES IN ANIMALS AND HUMANS. BASED ON THE AVAILABLE EVIDENCE, IT IS CONCLUDED THAT INTAKE OF DIFFERENT AMOUNTS OF DIETARY METHYL DONORS AND COFACTORS DURING PREGNANCY MAY ALTER FETAL GROWTH AND DEVELOPMENT, THUS ESTABLISHING A MAJOR LINK BETWEEN EARLY ENVIRONMENTAL EXPOSURE AND DISEASE DEVELOPMENT IN THE OFFSPRING LATER IN LIFE. 2018 5 4406 25 MOLECULAR ALTERATIONS IN HEPATOCARCINOGENESIS INDUCED BY DIETARY METHYL DEFICIENCY. A CHRONIC DEFICIENCY OF MAJOR DIETARY METHYL GROUP DONORS--METHIONINE, CHOLINE, FOLIC ACID, AND VITAMIN B12--CAN INDUCE THE DEVELOPMENT OF LIVER CANCER IN RODENTS. FEEDING METHYL-DEFICIENT DIETS CAUSES SEVERAL MOLECULAR ALTERATIONS, INCLUDING ALTERED LIPID METABOLISM, OXIDATIVE STRESS, DEREGULATED ONE-CARBON METABOLISM, AND A NUMBER OF EPIGENETIC ABNORMALITIES THAT RESULT IN PROGRESSIVE LIVER INJURY CULMINATING IN THE DEVELOPMENT OF PRIMARY LIVER TUMORS. IMPORTANTLY, THIS METHYL-DEFICIENT MODEL OF ENDOGENOUS HEPATOCARCINOGENESIS IS ONE OF THE MOST RELEVANT MODELS OF HUMAN LIVER CARCINOGENESIS THAT ALLOWS STUDYING LIVER CANCER PATHOGENESIS BY SUBSTANTIALLY COMPLEMENTING MANY SHORTCOMINGS OF HUMANS-ONLY STUDIES. IN THIS REVIEW, WE DESCRIBE MOLECULAR CHANGES AND THEIR ROLE IN PATHOGENESIS OF LIVER CARCINOGENESIS INDUCED BY METHYL DEFICIENCY. 2012 6 6094 38 THE EFFECTS OF MATERNAL AND POSTNATAL DIETARY METHYL NUTRIENTS ON EPIGENETIC CHANGES THAT LEAD TO NON-COMMUNICABLE DISEASES IN ADULTHOOD. THE RISK FOR NON-COMMUNICABLE DISEASES IN ADULTHOOD CAN BE PROGRAMMED BY EARLY NUTRITION. THIS PROGRAMMING IS MEDIATED BY CHANGES IN EXPRESSION OF KEY GENES IN VARIOUS METABOLIC PATHWAYS DURING DEVELOPMENT, WHICH PERSIST INTO ADULTHOOD. THESE DEVELOPMENTAL MODIFICATIONS OF GENES ARE DUE TO EPIGENETIC ALTERATIONS IN DNA METHYLATION PATTERNS. RECENT STUDIES HAVE DEMONSTRATED THAT DNA METHYLATION CAN BE AFFECTED BY MATERNAL OR EARLY POSTNATAL DIETS. BECAUSE METHYL GROUPS FOR METHYLATION REACTIONS COME FROM METHIONINE CYCLE NUTRIENTS (I.E., METHIONINE, CHOLINE, BETAINE, FOLATE), DEFICIENCY OR SUPPLEMENTATION OF THESE METHYL NUTRIENTS CAN DIRECTLY CHANGE EPIGENETIC REGULATION OF GENES PERMANENTLY. ALTHOUGH MANY STUDIES HAVE DESCRIBED THE EARLY PROGRAMMING OF ADULT DISEASES BY MATERNAL AND INFANT NUTRITION, THIS REVIEW DISCUSSES STUDIES THAT HAVE ASSOCIATED EARLY DIETARY METHYL NUTRIENT MANIPULATION WITH DIRECT EFFECTS ON EPIGENETIC PATTERNS THAT COULD LEAD TO CHRONIC DISEASES IN ADULTHOOD. THE MATERNAL SUPPLY OF METHYL NUTRIENTS DURING GESTATION AND LACTATION CAN ALTER EPIGENETICS, BUT PROGRAMMING EFFECTS VARY DEPENDING ON THE TIMING OF DIETARY INTERVENTION, THE TYPE OF METHYL NUTRIENT MANIPULATED, AND THE TISSUE RESPONSIBLE FOR THE PHENOTYPE. MOREOVER, THE POSTNATAL MANIPULATION OF METHYL NUTRIENTS CAN PROGRAM EPIGENETICS, BUT MORE RESEARCH IS NEEDED ON WHETHER THIS APPROACH CAN RESCUE MATERNALLY PROGRAMMED OFFSPRING. 2020 7 558 31 B-VITAMIN DEPENDENT METHIONINE METABOLISM AND ALCOHOLIC LIVER DISEASE. CONVINCING EVIDENCE LINKS ABERRANT B-VITAMIN DEPENDENT HEPATIC METHIONINE METABOLISM TO THE PATHOGENESIS OF ALCOHOLIC LIVER DISEASE (ALD). THIS REVIEW FOCUSES ON THE ESSENTIAL ROLES OF FOLATE AND VITAMINS B6 AND B12 IN HEPATIC METHIONINE METABOLISM, THE CAUSES OF THEIR DEFICIENCIES AMONG CHRONIC ALCOHOLIC PERSONS, AND HOW THEIR DEFICIENCIES TOGETHER WITH CHRONIC ALCOHOL EXPOSURE IMPACT ON ABERRANT METHIONINE METABOLISM IN THE PATHOGENESIS OF ALD. FOLATE IS THE DIETARY TRANSMETHYLATION DONOR FOR THE PRODUCTION OF S-ADENOSYLMETHIONINE (SAM), WHICH IS THE SUBSTRATE FOR ALL METHYLTRANSFERASES THAT REGULATE GENE EXPRESSIONS IN PATHWAYS OF LIVER INJURY, AS WELL AS A REGULATOR OF THE TRANSSULFURATION PATHWAY THAT IS ESSENTIAL FOR PRODUCTION OF GLUTATHIONE (GSH), THE PRINCIPAL ANTIOXIDANT FOR DEFENSE AGAINST OXIDATIVE LIVER INJURY. VITAMIN B12 REGULATES TRANSMETHYLATION REACTIONS FOR SAM PRODUCTION AND VITAMIN B6 REGULATES TRANSSULFURATION REACTIONS FOR GSH PRODUCTION. FOLATE DEFICIENCY ACCELERATES THE EXPERIMENTAL DEVELOPMENT OF ALD IN ETHANOL-FED ANIMALS WHILE REDUCING LIVER SAM LEVELS WITH RESULTANT ABNORMAL GENE EXPRESSION AND DECREASED PRODUCTION OF ANTIOXIDANT GSH. THROUGH ITS EFFECTS ON FOLATE METABOLISM, REDUCED SAM ALSO IMPAIRS NUCLEOTIDE BALANCE WITH RESULTANT INCREASED DNA STRAND BREAKS, OXIDATION, HEPATOCELLULAR APOPTOSIS, AND RISK OF CARCINOGENESIS. THE REVIEW ENCOMPASSES REFERENCED STUDIES ON MECHANISMS FOR PERTURBATIONS OF METHIONINE METABOLISM IN ALD, EVIDENCE FOR ALTERED GENE EXPRESSIONS AND THEIR EPIGENETIC REGULATION IN THE PATHOGENESIS OF ALD, AND CLINICAL STUDIES ON POTENTIAL PREVENTION AND TREATMENT OF ALD BY CORRECTION OF METHIONINE METABOLISM WITH SAM. 2013 8 2158 50 EPIGENETIC MECHANISMS FOR NUTRITION DETERMINANTS OF LATER HEALTH OUTCOMES. EPIGENETIC MARKING ON GENES CAN DETERMINE WHETHER OR NOT GENES ARE EXPRESSED. EPIGENETIC REGULATION IS MEDIATED BY THE ADDITION OF METHYL GROUPS TO DNA CYTOSINE BASES, OF METHYL AND ACETYL GROUPS TO PROTEINS (HISTONES) AROUND WHICH DNA IS WRAPPED, AND BY SMALL INTERFERING RNA MOLECULES. SOME COMPONENTS OF EPIGENETIC REGULATION HAVE EVOLVED TO PERMIT CONTROL OF WHETHER MATERNAL OR PATERNAL GENES ARE EXPRESSED. THE EPIGENETIC IMPRINTING OF IGF2 EXPRESSION IS AN EXAMPLE OF MATERNAL AND PATERNAL EPIGENETIC MARKING THAT MODULATES FETAL GROWTH AND FETAL SIZE. HOWEVER, EPIGENETIC REGULATION ALSO PERMITS THE FETUS AND THE INFANT TO ADAPT GENE EXPRESSION TO THE ENVIRONMENT IN WHICH IT IS GROWING; SOMETIMES WHEN THIS ADJUSTMENT GOES AWRY, THE RISK OF CHRONIC DISEASE IS INCREASED. RECENT PROGRESS IN THE UNDERSTANDING OF NUTRITIONAL INFLUENCES ON EPIGENETICS SUGGESTS THAT NUTRIENTS THAT ARE PART OF METHYL-GROUP METABOLISM CAN SIGNIFICANTLY INFLUENCE EPIGENETICS. DURING CRITICAL PERIODS IN DEVELOPMENT, DIETARY METHYL-GROUP INTAKE (CHOLINE, METHIONINE, AND FOLATE) CAN ALTER DNA AND HISTONE METHYLATION, WHICH RESULTS IN LIFELONG CHANGES IN GENE EXPRESSION. IN RODENT MODELS, PREGNANT DAMS THAT WERE FED DIETS HIGH IN METHIONINE, FOLIC ACID, AND CHOLINE PRODUCED OFFSPRING WITH DIFFERENT COAT COLORS OR WITH KINKED TAILS. A NUMBER OF SYNDROMES IN HUMANS CAN BE CAUSED BY DEFECTIVE EPIGENETIC REGULATION, INCLUDING RETT SYNDROME. THERE ARE INTERESTING EXAMPLES OF THE EFFECTS OF NUTRITION IN EARLY LIFE THAT RESULT IN ALTERED HEALTH IN ADULTS, AND SOME OF THESE COULD BE THE RESULT OF ALTERED EPIGENETIC REGULATION OF GENE EXPRESSION. 2009 9 3852 41 IS MATERNAL MICROBIAL METABOLISM AN EARLY-LIFE DETERMINANT OF HEALTH? MOUNTING EVIDENCE SUGGESTS THAT ENVIRONMENTAL STRESS EXPERIENCED IN UTERO (FOR EXAMPLE, MATERNAL NUTRITIONAL DEFICITS) ESTABLISHES A PREDISPOSITION IN THE NEWBORN TO THE DEVELOPMENT OF CHRONIC DISEASES LATER IN LIFE. THIS CONCEPT IS OFTEN REFERRED TO AS THE "FETAL ORIGINS HYPOTHESIS" OR "DEVELOPMENTAL ORIGINS OF HEALTH AND DISEASE". SINCE ITS FIRST PROPOSAL, EPIGENETICS HAS EMERGED AS AN UNDERLYING MECHANISM EXPLAINING HOW ENVIRONMENTAL CUES BECOME GESTATIONALLY "ENCODED". MANY OF THE ENZYMES THAT IMPART AND MAINTAIN EPIGENETIC MODIFICATIONS ARE HIGHLY SENSITIVE TO NUTRIENT AVAILABILITY, WHICH CAN BE INFLUENCED BY THE METABOLIC ACTIVITIES OF THE INTESTINAL MICROBIOTA. THEREFORE, THE MATERNAL MICROBIOME HAS THE POTENTIAL TO INFLUENCE EPIGENETICS IN UTERO AND MODULATE OFFSPRING'S LONG-TERM HEALTH TRAJECTORIES. HERE WE SUMMARIZE THE CURRENT UNDERSTANDING OF THE INTERACTIONS THAT OCCUR BETWEEN THE MATERNAL GUT MICROBIOME AND THE ESSENTIAL NUTRIENT CHOLINE, THAT IS NOT ONLY REQUIRED FOR FETAL DEVELOPMENT AND EPIGENETIC REGULATION BUT IS ALSO A GROWTH SUBSTRATE FOR SOME MICROBES. BACTERIA ABLE TO METABOLIZE CHOLINE BENEFIT FROM THE PRESENCE OF THIS NUTRIENT AND COMPETE WITH THE HOST FOR ITS ACCESS, WHICH UNDER EXTREME CONDITIONS MAY ELICIT SIGNATURES OF CHOLINE DEFICIENCY. ANOTHER CONSEQUENCE OF BACTERIAL CHOLINE METABOLISM IS THE ACCUMULATION OF THE PRO-INFLAMMATORY, PRO-THROMBOTIC METABOLITE TRIMETHYLAMINE-N-OXIDE (TMAO). FINALLY, WE DISCUSS HOW THESE DIFFERENT FACETS OF MICROBIAL CHOLINE METABOLISM MAY INFLUENCE INFANT DEVELOPMENT AND HEALTH TRAJECTORIES VIA EPIGENETIC MECHANISMS AND MORE BROADLY PLACE A CALL TO ACTION TO BETTER UNDERSTAND HOW MATERNAL MICROBIAL METABOLISM CAN SHAPE THEIR OFFSPRING'S PROPENSITY TO CHRONIC DISEASE DEVELOPMENT LATER IN LIFE. 2018 10 6717 35 VITAMIN B SUPPLEMENTATION AND NUTRITIONAL INTAKE OF METHYL DONORS IN PATIENTS WITH CHRONIC KIDNEY DISEASE: A CRITICAL REVIEW OF THE IMPACT ON EPIGENETIC MACHINERY. CARDIOVASCULAR MORBIDITY AND MORTALITY ARE SEVERAL-FOLD HIGHER IN PATIENTS WITH ADVANCED CHRONIC KIDNEY DISEASE (CKD) AND END-STAGE RENAL DISEASE (ESRD) THAN IN THE GENERAL POPULATION. HYPERHOMOCYSTEINEMIA HAS UNDOUBTEDLY A CENTRAL ROLE IN SUCH A PROMINENT CARDIOVASCULAR BURDEN. THE LEVELS OF HOMOCYSTEINE ARE REGULATED BY METHYL DONORS (FOLATE, METHIONINE, CHOLINE, BETAINE), AND COFACTORS (VITAMIN B6, VITAMIN B12,). UREMIA-INDUCED HYPERHOMOCYSTEINEMIA HAS AS ITS MAIN TARGETS DNA METHYLTRANSFERASES, AND THIS LEADS TO AN ALTERED EPIGENETIC CONTROL OF GENES REGULATED THROUGH METHYLATION. IN RENAL PATIENTS, THE EPIGENETIC LANDSCAPE IS STRICTLY CORRELATED WITH THE UREMIC PHENOTYPE AND DEPENDENT ON DIETARY INTAKE OF MICRONUTRIENTS, INFLAMMATION, GUT MICROBIOME, INFLAMMATORY STATUS, OXIDATIVE STRESS, AND LIFESTYLE HABITS. ALL THESE FACTORS ARE KEY CONTRIBUTORS IN METHYLOME MAINTENANCE AND IN THE MODULATION OF GENE TRANSCRIPTION THROUGH DNA HYPO- OR HYPERMETHYLATION IN CKD. THIS IS AN OVERVIEW OF THE EPIGENETIC CHANGES RELATED TO DNA METHYLATION IN PATIENTS WITH ADVANCED CKD AND ESRD. WE EXPLORED THE CURRENTLY AVAILABLE DATA ON THE MOLECULAR DYSREGULATIONS RESULTING FROM ALTERED GENE EXPRESSION IN UREMIA. SPECIAL ATTENTION WAS PAID TO THE EFFICACY OF B-VITAMINS SUPPLEMENTATION AND DIETARY INTAKE OF METHYL DONORS ON HOMOCYSTEINE LOWERING AND CARDIOVASCULAR PROTECTION. 2020 11 1836 19 EFFECTS OF NUTRIENT AND BIOACTIVE FOOD COMPONENTS ON ALZHEIMER'S DISEASE AND EPIGENETIC. ALZHEIMER'S DISEASE (AD) IS THE MOST COMMON FORM OF DEMENTIA IN THE ELDERLY AND IS A CHRONIC NEURODEGENERATIVE DISEASE THAT IS BECOMING WIDESPREAD. FOR THIS REASON, IN RECENT YEARS FACTORS AFFECTING THE DEVELOPMENT, PROGRESSION AND COGNITIVE FUNCTION OF THE AD HAVE BEEN EMPHASIZED. NUTRIENTS AND OTHER BIOACTIVE NUTRIENTS ARE AMONG THE FACTORS THAT ARE EFFECTIVE IN AD. IN PARTICULAR, VITAMINS A, C AND E, VITAMINS B(1), B(6) AND B(12), FOLATE, MAGNESIUM, CHOLINE, INOSITOL, ANTHOCYANINS, ISOFLAVONES ETC. NUTRIENTS AND BIOACTIVE NUTRIENTS ARE KNOWN TO BE EFFECTIVE IN THE DEVELOPMENT OF AD. NUTRIENTS AND NUTRIENT COMPONENTS MAY ALSO HAVE AN EPIGENETIC EFFECT ON AD. AT THE SAME TIME, NUTRIENTS AND BIOACTIVE FOOD COMPONENTS SLOW DOWN THE PROGRESSION OF THE DISEASE. FOR THIS REASON, THE EFFECT OF NUTRIENTS AND FOOD COMPONENTS ON AD WAS EXAMINED IN THIS REVIEW. 2019 12 1939 24 EPIDEMIOLOGY AND (PATHO)PHYSIOLOGY OF FOLIC ACID SUPPLEMENT USE IN OBESE WOMEN BEFORE AND DURING PREGNANCY. PRECONCEPTION FOLIC ACID SUPPLEMENT USE IS A WELL-KNOWN METHOD OF PRIMARY PREVENTION OF NEURAL TUBE DEFECTS (NTDS). OBESE WOMEN ARE AT A HIGHER RISK FOR HAVING A CHILD WITH A NTD. AS DIFFERENT INTERNATIONAL RECOMMENDATIONS ON FOLIC ACID SUPPLEMENT USE FOR OBESE WOMEN BEFORE AND DURING PREGNANCY EXIST, THIS NARRATIVE REVIEW PROVIDES AN OVERVIEW OF EPIDEMIOLOGY OF FOLATE DEFICIENCY IN OBESE (PRE)PREGNANT WOMEN, ELABORATES ON POTENTIAL MECHANISMS UNDERLYING FOLATE DEFICIENCY, AND DISCUSSES CONSIDERATIONS FOR THE USAGE OF HIGHER DOSES OF FOLIC ACID SUPPLEMENTS. WOMEN WITH OBESITY MORE OFTEN SUFFER FROM AN ABSOLUTE FOLATE DEFICIENCY, AS THEY ARE LESS COMPLIANT TO PERICONCEPTIONAL FOLIC ACID SUPPLEMENT USE RECOMMENDATIONS. IN ADDITION, THEIR DIETARY FOLATE INTAKE IS LIMITED DUE TO AN UNBALANCED DIET (RELATIVE MALNUTRITION). THE ASSOCIATION OF OBESITY AND NTDS ALSO SEEMS TO BE INDEPENDENT OF FOLATE INTAKE, WITH STUDIES SUGGESTING AN INCREASED NEED OF FOLATE (RELATIVE DEFICIENCY) DUE TO DERANGEMENTS INVOLVED IN OTHER PATHWAYS. THE RELATIVE FOLATE DEFICIENCY, AS A RESULT OF AN INCREASED METABOLIC NEED FOR FOLATE IN OBESE WOMEN, CAN BE DUE TO: (1) LOW-GRADE CHRONIC INFLAMMATION (2) INSULIN RESISTANCE, (3) INOSITOL, AND (4) DYSBIOTIC GUT MICROBIOME, WHICH PLAYS A ROLE IN FOLATE PRODUCTION AND UPTAKE. IN ALL THESE PATHWAYS, THE FOLATE-DEPENDENT ONE-CARBON METABOLISM IS INVOLVED. IN CONCLUSION, SCIENTIFIC EVIDENCE OF THE INVOLVEMENT OF SEVERAL FOLATE-RELATED PATHWAYS IMPLIES TO INCREASE THE RECOMMENDED FOLIC ACID SUPPLEMENTATION IN OBESE WOMEN. HOWEVER, THE PHYSIOLOGICAL UPTAKE OF SYNTHETIC FOLIC ACID IS LIMITED AND SIDE-EFFECTS OF UNMETABOLIZED FOLIC ACID IN MOTHERS AND OFFSPRING, IN PARTICULAR VARIATIONS IN EPIGENETIC (RE)PROGRAMMING WITH LONG-TERM HEALTH EFFECTS, CANNOT BE EXCLUDED. THEREFORE, WE EMPHASIZE ON THE URGENT NEED FOR FURTHER RESEARCH AND PRECONCEPTION PERSONALIZED COUNSELING ON FOLATE STATUS, LIFESTYLE, AND MEDICAL CONDITIONS. 2021 13 4398 31 MODULATION OF DNA METHYLTRANSFERASE PROFILE BY METHYL DONOR STARVATION FOLLOWED BY GAMMA IRRADIATION. DNA METHYLATION IS AN IMPORTANT EPIGENETIC MECHANISM OF TRANSCRIPTIONAL CONTROL, WHICH PLAYS AN ESSENTIAL ROLE IN MAINTAINING CELLULAR FUNCTION. ROLE OF ONE-CARBON TRANSFER AGENTS/METHYL DONORS NAMELY FOLATE, CHOLINE AND METHIONINE IN DNA METHYLATION HAS BEEN THE SUBJECT OF EXTENSIVE INVESTIGATION. THE METHYLATION PATTERN OF DNA IS ESTABLISHED DURING EMBRYOGENESIS BY DNA METHYLTRANSFERASE 3 (DNMT3) AND IS SUBSEQUENTLY MAINTAINED BY MAINTENANCE METHYLATION ACTIVITY OF THE ENZYME DNA METHYLTRANSFERASE 1 (DNMT1). IONIZING RADIATION IS KNOWN TO EXTENSIVELY DAMAGE THE DNA. SUFFICIENT DIETARY AVAILABILITY OF METHYL DONORS IS KNOWN TO CONTRIBUTE TOWARDS ONE-CARBON TRANSFER MEDIATED REPAIR OF DAMAGED DNA WHERE FOLATE IS INVOLVED IN NUCLEOTIDE BASE SYNTHESIS. IN THE PRESENT STUDY, MODIFICATION IN ACTIVITIES OF DNMT1 AND DNMT3 BY METHYL DONOR STARVATION FOLLOWED BY GAMMA-IRRADIATION WAS OBSERVED. ASSAYS WERE BASED ON THE CATALYTIC TRANSFER OF (3)H-METHYL GROUPS FROM S-ADENOSYL-L: -METHIONINE TO A DNA SUBSTRATE. EXPERIMENTS SHOWED A DOSE AND METHYL DONORS STARVATION DEPENDENT ATTENUATION IN DNMT1 ACTIVITY. ATTENUATION OF DNMT1 ACTIVITY WAS MOST SIGNIFICANT FOR DIET DEPRIVED OF ALL THE THREE-METHYL DONORS. NO SIGNIFICANT CHANGE IN NUCLEAR OR CYTOPLASMIC DNMT3 ACTIVITY WAS OBSERVED WHEN EITHER OR ALL THE THREE POSSIBLE SOURCE OF DIETARY METHYL GROUP SUPPLY WERE REMOVED. IONIZING RADIATION AND METHYL DONOR DEFICIENCY WERE OBSERVED TO ACT SYNERGISTICALLY TOWARDS INHIBITING DNMT1 ACTIVITY. PRESENT RESULTS SUGGESTED POSSIBILITY OF INTERACTION AMONG FOLATE, METHIONINE AND CHOLINE DEFICIENCY TO POTENTIATE SYMPTOMS OF IONIZING RADIATION STRESS. THESE ENZYMATIC MODIFICATIONS MIGHT CONTRIBUTE TO ALTERED DNA METHYLATION AFTER CHRONIC FEEDING OF METHYL DONOR FREE DIETS FOLLOWED BY GAMMA IRRADIATION. THESE RESULTS SUGGESTED THAT DIETARY AVAILABILITY OF METHYL DONORS AND GAMMA-RADIATION STRESS MIGHT SIGNIFICANTLY ALTER THE DNMT1 PROFILE. 2007 14 4219 38 METHYL-DONOR DEFICIENCY IN ADOLESCENCE AFFECTS MEMORY AND EPIGENETIC STATUS IN THE MOUSE HIPPOCAMPUS. DNA METHYLATION IS ONE OF THE ESSENTIAL FACTORS IN THE CONTROL OF GENE EXPRESSION. ALTERATION OF THE DNA METHYLATION PATTERN HAS BEEN LINKED TO VARIOUS NEUROLOGICAL, BEHAVIORAL AND NEUROCOGNITIVE DYSFUNCTIONS. RECENT STUDIES HAVE POINTED OUT THE IMPORTANCE OF EPIGENETICS IN BRAIN DEVELOPMENT AND FUNCTIONS INCLUDING LEARNING AND MEMORY. NUTRIENTS RELATED TO ONE-CARBON METABOLISM ARE KNOWN TO PLAY IMPORTANT ROLES IN THE MAINTENANCE OF GENOMIC DNA METHYLATION. PREVIOUS STUDIES HAVE SHOWN THAT THE LONG-TERM ADMINISTRATION OF A DIET LACKING ESSENTIAL ONE-CARBON NUTRIENTS SUCH AS METHIONINE, CHOLINE AND FOLIC ACID (METHYL DONORS) CAUSED GLOBAL DNA HYPERMETHYLATION IN THE BRAIN. THEREFORE, THE LONG-TERM FEEDING OF A METHYL-DONOR-DEFICIENT DIET MAY CAUSE ABNORMAL BRAIN DEVELOPMENT INCLUDING LEARNING AND MEMORY. TO CONFIRM THIS HYPOTHESIS, 3-WEEK-OLD MICE WERE MAINTAINED ON A FOLATE-, METHIONINE- AND CHOLINE-DEFICIENT (FMCD) OR CONTROL (CON) DIET FOR 3 WEEKS. WE FOUND THAT THE METHYL-DONOR DEFICIENCY IMPAIRED BOTH NOVEL OBJECT RECOGNITION AND FEAR EXTINCTION AFTER 3 WEEKS OF TREATMENT. THE FMCD GROUP SHOWED SPONTANEOUS RECOVERY OF FEAR THAT DIFFERED FROM THAT IN CON. IN ADDITION, WE FOUND DECREASED GRIA1 GENE EXPRESSION AND SPECIFIC CPG HYPERMETHYLATION OF THE GRIA1 PROMOTER REGION IN THE FMCD HIPPOCAMPUS. OUR DATA SUGGEST THAT A CHRONIC DIETARY LACK OF METHYL DONORS IN THE DEVELOPMENTAL PERIOD AFFECTS LEARNING, MEMORY AND GENE EXPRESSIONS IN THE HIPPOCAMPUS. 2015 15 4214 43 METHIONINE METABOLISM IN YUCATAN MINIATURE SWINE. METHIONINE IS AN ESSENTIAL AMINO ACID WHICH WHEN NOT INCORPORATED INTO PROTEIN, CAN BE CONVERTED TO S-ADENOSYLMETHIONINE, THE UNIVERSAL METHYL DONOR IN OVER 200 TRANSMETHYLATION REACTIONS, WHICH INCLUDE CREATINE AND PHOSPHATIDYLCHOLINE (PC) SYNTHESIS, AS WELL AS DEOXYRIBONUCLEIC ACID (DNA) METHYLATION. FOLLOWING TRANSMETHYLATION, HOMOCYSTEINE IS FORMED, WHICH CAN BE CONVERTED TO CYSTEINE VIA TRANSSULFURATION OR REMETHYLATED TO METHIONINE BY RECEIVING A METHYL GROUP FROM FOLATE OR BETAINE. CHANGES TO METHYL GROUP AVAILABILITY IN UTERO CAN LEAD TO PERMANENT CHANGES IN EPIGENETIC PATTERNS OF DNA METHYLATION, WHICH HAS BEEN IMPLICATED IN "FETAL PROGRAMMING", A PHENOMENON ASSOCIATED WITH POOR NUTRITION DURING FETAL DEVELOPMENT THAT RESULTS IN LOW BIRTH WEIGHT AND DISEASE IN LATER LIFE. IT HAS BEEN SHOWN THAT PROGRAMMING CAN ALSO OCCUR IN THE NEONATE. OUR GLOBAL OBJECTIVE WAS TO UNDERSTAND HOW THE VARIABILITY OF NUTRIENTS INVOLVED IN METHIONINE METABOLISM CAN AFFECT METHIONINE AND METHYL GROUP AVAILABILITY. WE HYPOTHESIZE THAT NUTRIENTS THAT CONVERGE ON METHIONINE METABOLISM CAN AFFECT METHIONINE AVAILABILITY FOR ITS VARIOUS FUNCTIONS. IN THIS THESIS, WE USED INTRAUTERINE GROWTH RESTRICTED (IUGR) PIGLETS TO INVESTIGATE WHETHER A GLOBAL NUTRITIONAL INSULT IN UTERO CAN LEAD TO A PERTURBED METHIONINE METABOLISM. OUR RESULTS DEMONSTRATE THAT IUGR PIGLETS HAVE A LOWER CAPACITY TO DISPOSE OF HOMOCYSTEINE VIA BOTH TRANSSULFURATION AND REMETHYLATION PATHWAYS, AS WELL AS A LOWER INCORPORATION OF METHYL GROUPS INTO PC. THE SECOND OBJECTIVE OF THIS THESIS WAS TO DETERMINE WHETHER VARIATION IN METHIONINE SUPPLY AND DEMAND CAN AFFECT METHIONINE AVAILABILITY. WE DEMONSTRATED THAT STIMULATING EITHER ACUTE OR CHRONIC CREATINE SYNTHESIS LEADS TO LOWER METHYL INCORPORATION INTO PROTEIN AND PC IN PIGS. FURTHERMORE, WHEN METHIONINE IS LIMITING, SUPPLEMENTATION WITH EITHER FOLATE OR BETAINE LEADS TO HIGHER METHIONINE AVAILABILITY FOR PROTEIN SYNTHESIS. FINALLY, BECAUSE CREATINE IS INCREASINGLY BEING UTILIZED AS AN ERGOGENIC AND NEUROPROTECTIVE SUPPLEMENT, WE WANTED TO DETERMINE WHETHER PROVISION OF THE CREATINE PRECURSOR, GUANIDINOACETATE (GAA), COULD EFFECTIVELY INCREASE TISSUE CREATINE STORES. WE SHOWED THAT 2.5 WEEKS OF SUPPLEMENTATION WITH GAA IS MORE EFFECTIVE THAN CREATINE AT INCREASING HEPATIC AND MUSCLE CREATINE STORES. THE RESULTS OF THIS THESIS DEMONSTRATE THAT THE PRESENCE OF IUGR, AN INCREASED DEMAND FOR CREATINE SYNTHESIS, OR THE SUPPLEMENTATION WITH REMETHYLATION NUTRIENTS CAN EACH AFFECT METHIONINE AVAILABILITY; ALL ARE IMPORTANT WHEN CONSIDERING NEONATAL NUTRIENT REQUIREMENTS. FURTHERMORE, ALTHOUGH GAA IS EFFECTIVE AT INCREASING LEVELS OF TISSUE CREATINE, HIGHER GAA METHYLATION CAN LIMIT METHIONINE AVAILABILITY FOR GROWTH AND SYNTHESIS OF PC. 2016 16 4925 31 PARENTAL MICRONUTRIENT DEFICIENCY DISTORTS LIVER DNA METHYLATION AND EXPRESSION OF LIPID GENES ASSOCIATED WITH A FATTY-LIVER-LIKE PHENOTYPE IN OFFSPRING. MICRONUTRIENT STATUS OF PARENTS CAN AFFECT LONG TERM HEALTH OF THEIR PROGENY. AROUND 2 BILLION HUMANS ARE AFFECTED BY CHRONIC MICRONUTRIENT DEFICIENCY. IN THIS STUDY WE USE ZEBRAFISH AS A MODEL SYSTEM TO EXAMINE MORPHOLOGICAL, MOLECULAR AND EPIGENETIC CHANGES IN MATURE OFFSPRING OF PARENTS THAT EXPERIENCED A ONE-CARBON (1-C) MICRONUTRIENT DEFICIENCY. ZEBRAFISH WERE FED A DIET SUFFICIENT, OR MARGINALLY DEFICIENT IN 1-C NUTRIENTS (FOLATE, VITAMIN B12, VITAMIN B6, METHIONINE, CHOLINE), AND THEN MATED. OFFSPRING LIVERS UNDERWENT HISTOLOGICAL EXAMINATION, RNA SEQUENCING AND GENOME-WIDE DNA METHYLATION ANALYSIS. PARENTAL 1-C MICRONUTRIENT DEFICIENCY RESULTED IN INCREASED LIPID INCLUSION AND WE IDENTIFIED 686 DIFFERENTIALLY EXPRESSED GENES IN OFFSPRING LIVER, THE MAJORITY OF WHICH WERE DOWNREGULATED. DOWNREGULATED GENES WERE ENRICHED FOR FUNCTIONAL CATEGORIES RELATED TO STEROL, STEROID AND LIPID BIOSYNTHESIS, AS WELL AS MITOCHONDRIAL PROTEIN SYNTHESIS. DIFFERENTIAL DNA METHYLATION WAS FOUND AT 2869 CPG SITES, ENRICHED IN PROMOTER REGIONS AND PERMUTATION ANALYSES CONFIRMED THE ASSOCIATION WITH PARENTAL FEED. OUR DATA INDICATE THAT PARENTAL 1-C NUTRIENT STATUS CAN PERSIST AS LOCUS SPECIFIC DNA METHYLATION MARKS IN DESCENDANTS AND SUGGEST AN EFFECT ON LIPID UTILIZATION AND MITOCHONDRIAL PROTEIN TRANSLATION IN F(1) LIVERS. THIS POINTS TOWARD PARENTAL MICRONUTRIENTS STATUS AS AN IMPORTANT FACTOR FOR OFFSPRING HEALTH AND WELFARE. 2018 17 3649 30 INCREASED STRESS AND ALTERED EXPRESSION OF HISTONE MODIFYING ENZYMES IN BRAIN ARE ASSOCIATED WITH ABERRANT BEHAVIOUR IN VITAMIN B12 DEFICIENT FEMALE MICE. A SUB-OPTIMAL NUTRITIONAL ENVIRONMENT FROM EARLY LIFE CAN BE ENVISAGED AS A STRESSOR THAT TRANSLATES INTO MENTAL HEALTH PROBLEMS IN ADULTHOOD. AFTER CONSIDERING (A) THE WIDESPREAD PREVALENCE OF VITAMIN B12 DEFICIENCY ESPECIALLY AMONGST WOMEN IN DEVELOPING COUNTRIES AND (B) THE IMPORTANCE OF VITAMIN B12 IN NORMAL BRAIN FUNCTION, IN THIS STUDY WE HAVE ELUCIDATED THE BEHAVIOURAL CORRELATES OF CHRONIC SEVERE AND MODERATE VITAMIN B12 DEFICIENCY IN C57BL/6 MICE. FEMALE WEANLING MICE WERE ASSIGNED TO THREE DIETARY GROUPS: (A) CONTROL AIN-76A DIET WITH CELLULOSE AS DIETARY FIBRE (B) VITAMIN B12 RESTRICTED AIN-76A DIET WITH PECTIN AS DIETARY FIBRE (SEVERE DEFICIENCY GROUP) AND (C) VITAMIN B12 RESTRICTED AIN-76A DIET WITH CELLULOSE AS DIETARY FIBRE (MODERATE DEFICIENCY GROUP). THE MICE RECEIVED THESE DIETS THROUGHOUT PREGNANCY, LACTATION AND THEREAFTER. NEST-BUILDING, MATERNAL CARE, ANXIETY AND DEPRESSIVE BEHAVIOURS WERE EVALUATED. OXIDATIVE STRESS, ACTIVITIES OF ANTIOXIDANT ENZYMES AND EXPRESSION OF VARIOUS HISTONE MODIFYING ENZYMES IN BRAIN WERE INVESTIGATED TO UNRAVEL THE PROBABLE UNDERLYING MECHANISMS. OUR DATA SUGGESTS THAT BOTH SEVERE AND MODERATE VITAMIN B12 DEFICIENCY INDUCED ANXIETY AND IMPAIRED MATERNAL CARE. HOWEVER, ONLY SEVERE VITAMIN B12 DEFICIENCY INDUCED DEPRESSION. OXIDATIVE STRESS AND POOR ANTIOXIDANT DEFENSE UNDERLIE THE DELETERIOUS EFFECTS OF BOTH SEVERE AND MODERATE VITAMIN B12 DEFICIENCY. ALTERED EXPRESSION OF HISTONE MODIFYING ENZYMES IN THE BRAIN OF SEVERELY DEFICIENT MICE IS SUGGESTIVE OF EPIGENETIC REPROGRAMMING. THIS STUDY SUGGESTS THAT CHRONIC VITAMIN B12 DEFICIENCY LEADS TO BEHAVIOURAL ANOMALIES IN FEMALE C57BL/6 MICE AND THE SEVERITY OF THESE OUTCOMES CAN BE CORRELATED TO THE LEVEL OF DEFICIENCY. 2020 18 6726 25 VITAMIN-DEPENDENT METHIONINE METABOLISM AND ALCOHOLIC LIVER DISEASE. EMERGING EVIDENCE INDICATES THAT ETHANOL-INDUCED ALTERATIONS IN HEPATIC METHIONINE METABOLISM PLAY A CENTRAL ROLE IN THE PATHOGENESIS OF ALCOHOLIC LIVER DISEASE (ALD). BECAUSE MALNUTRITION IS A UNIVERSAL CLINICAL FINDING IN THIS DISEASE AND HEPATIC METHIONINE METABOLISM IS DEPENDENT UPON DIETARY FOLATE AND VITAMINS B-6 AND B-12, ALD CAN BE CONSIDERED AN INDUCED NUTRITIONAL DISORDER THAT IS CONDITIONED BY ALCOHOL ABUSE. THE PRESENT REVIEW DESCRIBES THE ETIOLOGIES OF THESE 3 VITAMIN DEFICIENCIES IN ALD AND HOW THEY INTERACT WITH CHRONIC ETHANOL EXPOSURE TO ALTER HEPATIC METHIONINE METABOLISM. SUBSEQUENT SECTIONS FOCUS ON MOLECULAR MECHANISMS FOR THE INTERACTIONS OF ABERRANT METHIONINE METABOLISM WITH ETHANOL IN THE PATHOGENESIS OF ALD, IN PARTICULAR THE ROLE OF S-ADENOSYLMETHIONINE (SAM) IN REGULATING THE EPIGENETIC EXPRESSIONS OF GENES RELEVANT TO PATHWAYS OF LIVER INJURY. THE REVIEW WILL CONCLUDE WITH DESCRIPTIONS OF STUDIES ON THE EFFICACY OF SAM IN THE TREATMENT OF ALD AND WITH DISCUSSION OF POTENTIALLY FRUITFUL FUTURE AVENUES OF RESEARCH. 2011 19 4683 42 NEW PERSPECTIVES ON FOLATE TRANSPORT IN RELATION TO ALCOHOLISM-INDUCED FOLATE MALABSORPTION--ASSOCIATION WITH EPIGENOME STABILITY AND CANCER DEVELOPMENT. FOLATES ARE MEMBERS OF THE B-CLASS OF VITAMINS, WHICH ARE REQUIRED FOR THE SYNTHESIS OF PURINES AND PYRIMIDINES, AND FOR THE METHYLATION OF ESSENTIAL BIOLOGICAL SUBSTANCES, INCLUDING PHOSPHOLIPIDS, DNA, AND NEUROTRANSMITTERS. FOLATES CANNOT BE SYNTHESIZED DE NOVO BY MAMMALS; HENCE, AN EFFICIENT INTESTINAL ABSORPTION PROCESS IS REQUIRED. INTESTINAL FOLATE TRANSPORT IS CARRIER-MEDIATED, PH-DEPENDENT AND ELECTRONEUTRAL, WITH SIMILAR AFFINITY FOR OXIDIZED AND REDUCED FOLIC ACID DERIVATIVES. THE VARIOUS TRANSPORTERS, I.E. REDUCED FOLATE CARRIER, PROTON-COUPLED FOLATE TRANSPORTER, FOLATE-BINDING PROTEIN, AND ORGANIC ANION TRANSPORTERS, ARE INVOLVED IN THE FOLATE TRANSPORT PROCESS IN VARIOUS TISSUES. ANY IMPAIRMENT IN UPTAKE OF FOLATE CAN LEAD TO A STATE OF FOLATE DEFICIENCY, THE MOST PREVALENT VITAMIN DEFICIENCY IN WORLD, AFFECTING 10% OF THE POPULATION IN THE USA. SUCH IMPAIRMENTS IN FOLATE TRANSPORT OCCUR IN A VARIETY OF CONDITIONS, INCLUDING CHRONIC USE OF ETHANOL, SOME INBORN HEREDITARY DISORDERS, AND CERTAIN DISEASES. AMONG THESE, ETHANOL INGESTION HAS BEEN THE MAJOR CONTRIBUTOR TO FOLATE DEFICIENCY. ETHANOL-ASSOCIATED FOLATE DEFICIENCY CAN DEVELOP BECAUSE OF DIETARY INADEQUACY, INTESTINAL MALABSORPTION, ALTERED HEPATOBILIARY METABOLISM, ENHANCED COLONIC METABOLISM, AND INCREASED RENAL EXCRETION. ETHANOL REDUCES THE INTESTINAL AND RENAL UPTAKE OF FOLATE BY ALTERING THE BINDING AND TRANSPORT KINETICS OF FOLATE TRANSPORT SYSTEMS. ALSO, ETHANOL REDUCES THE EXPRESSION OF FOLATE TRANSPORTERS IN BOTH INTESTINE AND KIDNEY, AND THIS MIGHT BE A CONTRIBUTING FACTOR FOR FOLATE MALABSORPTION, LEADING TO FOLATE DEFICIENCY. THE MAINTENANCE OF INTRACELLULAR FOLATE HOMEOSTASIS IS ESSENTIAL FOR THE ONE-CARBON TRANSFER REACTIONS NECESSARY FOR DNA SYNTHESIS AND BIOLOGICAL METHYLATION REACTIONS. DNA METHYLATION IS AN IMPORTANT EPIGENETIC DETERMINANT IN GENE EXPRESSION, IN THE MAINTENANCE OF DNA INTEGRITY AND STABILITY, IN CHROMOSOMAL MODIFICATIONS, AND IN THE DEVELOPMENT OF MUTATIONS. ETHANOL, A TOXIN THAT IS CONSUMED REGULARLY, HAS BEEN FOUND TO AFFECT THE METHYLATION OF DNA. IN ADDITION TO ITS EFFECT ON DNA METHYLATION DUE TO FOLATE DEFICIENCY, ETHANOL COULD DIRECTLY EXERT ITS EFFECT THROUGH ITS INTERACTION WITH ONE-CARBON METABOLISM, IMPAIRMENT OF METHYL GROUP SYNTHESIS, AND AFFECTING THE ENZYMES REGULATING THE SYNTHESIS OF S-ADENOSYLMETHIONINE, THE PRIMARY METHYL GROUP DONOR FOR MOST BIOLOGICAL METHYLATION REACTIONS. THUS, ETHANOL PLAYS AN IMPORTANT ROLE IN THE PATHOGENESIS OF SEVERAL DISEASES THROUGH ITS POTENTIAL ABILITY TO MODULATE THE METHYLATION OF BIOLOGICAL MOLECULES. THIS REVIEW DISCUSSES THE UNDERLYING MECHANISM OF FOLATE MALABSORPTION IN ALCOHOLISM, THE MECHANISM OF METHYLATION-ASSOCIATED SILENCING OF GENES, AND HOW THE INTERACTION BETWEEN ETHANOL AND FOLATE DEFICIENCY AFFECTS THE METHYLATION OF GENES, THEREBY MODULATING EPIGENOME STABILITY AND THE RISK OF CANCER. 2009 20 6305 40 THE QUESTION IS WHETHER INTAKE OF FOLIC ACID FROM DIET ALONE DURING PREGNANCY IS SUFFICIENT. PREGNANCY AND FOLIC ACID: PREGNANCY IS THE MOST IMPORTANT PERIOD IN LIFE OF EVERY WOMAN, PARTIALLY FOR THE NUMBER OF PHYSIOLOGICAL ADAPTATIONS SHE IS GOING THROUGH, PARTIALLY FOR THE EXPECTANCE OF NEW LIFE. IN ADDITION, PREGNANCY IS THE "CRITICAL WINDOW" FOR DEVELOPMENT LATER IN CHILDHOOD, AS A PERIOD OF FOETAL PROGRAMMING DURING WHICH NUTRITION PLAYS ONE OF CRUCIAL ROLES. DESPITE THE GENERAL BELIEF THAT NUTRITION THROUGH PREGNANCY IS ADEQUATE AND CHARACTERIZED BY BETTER NUTRITIONAL HABITS, A NUMBER OF STUDIES DO NOT CORROBORATE THIS BELIEF. ROLE OF FOLIC ACID: AN ADEQUATE FOLATE BLOOD LEVEL IS NECESSARY FOR NORMAL CELL GROWTH, SYNTHESIS OF SEVERAL COMPOUNDS INCLUDING DEOXYRIBONUCLEIC ACID AND RIBONUCLEIC ACID, PROPER BRAIN AND NEUROLOGIC FUNCTIONS; IT IS INCLUDED IN THE REGULATION OF HOMOCYSTEINE LEVEL, AND CLOSELY RELATED TO THE VITAMIN B12 METABOLISM. FOLATE DEFICIENCY IN PREGNANCY IS RELATED TO NEURAL TUBE DEFECTS, OTHER NEUROLOGICAL DISORDERS, PRETERM DELIVERY AND LOW BIRTH WEIGHT. FOOD SOURCES: A CORRELATION BETWEEN FOLATE AND THE PREVENTION OF BROAD SPECTRUM OF CHRONIC DISEASES HAS BEEN CONFIRMED. EMERGING EVIDENCE FROM THE EPIGENETIC STUDIES IS NOW BRINGING EVEN MORE LIGHT ON THE LEVEL OF SIGNIFICANCE OF FOLIC ACID. A WIDE RANGE OF PLANT AND ANIMAL FOODS ARE THE NATURAL SOURCES OF FOLATE; LIVER, YEAST, MUSHROOMS, AND GREEN LEAFY VEGETABLES BEING THE MOST SIGNIFICANT. DIFFERENT WAYS OF FOOD PREPARATION INFLUENCE THE FOLATE STABILITY AND ITS BIOAVAILABILITY VARIES FROM 25 TO 50% FROM FOODS, 85% FROM ENRICHED FOODS OR 100% FROM SUPPLEMENTS. CONCLUSION: A GREAT AMOUNT OF SCIENTIFIC RESULTS HAS LED TO OFFICIAL RECOMMENDATIONS FOR FOLIC ACID SUPPLEMENTATION IN PREGNANT WOMEN AS WELL AS IN A NUMBER OF OBLIGATORY OR VOLUNTARY FORTIFICATION PROGRAMMES IN ORDER TO PREVENT THE FOLATE DEFICIENCY ON THE LEVEL OF DIFFERENT POPULATION GROUPS. NEVERTHELESS, THERE MUST BE A CERTAIN LEVEL OF PRECAUTION FOR ELDERLY BECAUSE FOLATE CAN MASK THE VITAMIN B12 DEFICIENCY WITH POSSIBLE FATAL OUTCOMES. 2014