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Keywords = 5-methyltetrahydrofolate

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12 pages, 1252 KiB  
Article
Low Dietary Folate Increases Developmental Delays in the Litters of Mthfr677TT Mice
by Karen E. Christensen, Marie-Lou Faquette, Vafa Keser, Alaina M. Reagan, Aaron T. Gebert, Teodoro Bottiglieri, Gareth R. Howell and Rima Rozen
Nutrients 2025, 17(15), 2536; https://doi.org/10.3390/nu17152536 - 1 Aug 2025
Viewed by 194
Abstract
Background/Objectives: Low folate intake before and during pregnancy increases the risk of neural tube defects and other adverse outcomes. Gene variants such as MTHFR 677C>T (rs1801133) may increase risks associated with suboptimal folate intake. Our objective was to use BALB/cJ Mthfr677C>T [...] Read more.
Background/Objectives: Low folate intake before and during pregnancy increases the risk of neural tube defects and other adverse outcomes. Gene variants such as MTHFR 677C>T (rs1801133) may increase risks associated with suboptimal folate intake. Our objective was to use BALB/cJ Mthfr677C>T mice to evaluate the effects of the TT genotype and low folate diets on embryonic development and MTHFR protein expression in pregnant mice. Methods: Female 677CC (mCC) and 677TT (mTT) mice were fed control (2 mg folic acid/kg (2D)), 1 mg folic acid/kg (1D) and 0.3 mg folic acid/kg (0.3D) diets before and during pregnancy. Embryos and maternal tissues were collected at embryonic day 10.5. Embryos were examined for developmental delays and defects. Methyltetrahydrofolate (methylTHF) and total homocysteine (tHcy) were measured in maternal plasma, and MTHFR protein expression was evaluated in maternal liver. Results: MethylTHF decreased due to the experimental diets and mTT genotype. tHcy increased due to 0.3D and mTT genotype; mTT 0.3D mice had significantly higher tHcy than the other groups. MTHFR expression was lower in mTT liver than mCC. MTHFR protein expression increased due to low folate diets in mCC mice, whereas in mTT mice, MTHFR expression increased only due to 1D. Developmental delays were increased in the litters of mTT mice fed 1D and 0.3D. Conclusions: The Mthfr677C>T mouse models the effects of the MTHFR 677TT genotype in humans and provides a folate-responsive model for examination of the effects of folate intake and the MTHFR 677C>T variant during gestation. Full article
(This article belongs to the Section Micronutrients and Human Health)
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10 pages, 290 KiB  
Article
The Associations of Serum Folate Forms with Metabolic Dysfunction-Associated Fatty Liver Disease and Liver Fibrosis: A Nationwide Cross-Sectional Study
by Hai Zhao, Wei Fan, Yan Yan, Yuxing Liu and Xuejun Kang
Metabolites 2025, 15(6), 370; https://doi.org/10.3390/metabo15060370 - 5 Jun 2025
Viewed by 627
Abstract
Background: Accumulating evidence indicates a link between folate and metabolic dysfunction-associated fatty liver disease (MAFLD). Objectives: The aim of this study was to ascertain whether different serum folate forms are associated with newly defined MAFLD as well as liver fibrosis in [...] Read more.
Background: Accumulating evidence indicates a link between folate and metabolic dysfunction-associated fatty liver disease (MAFLD). Objectives: The aim of this study was to ascertain whether different serum folate forms are associated with newly defined MAFLD as well as liver fibrosis in the US general population. Methods: This cross-sectional study used data from the 2017–2020 (March) cycle and 2017–2018 cycle of the National Health and Nutrition Examination Survey (NHANES) in the US. Hepatic steatosis and fibrosis were evaluated by transient elastography, which employed controlled attenuation parameters and liver stiffness measurements as assessment indicators. Results: 7447 eligible individuals were included. The estimated prevalence of MAFLD and liver fibrosis was 51.6% (95% confidence interval [CI]: 50.4–52.7%) and 10.0% (95% CI: 9.3–10.7%). After adjusting for confounding factors, for every 1 nmol/L increase in serum 5-methyltetrahydrofolate (5-mTHF), the risk of developing liver fibrosis decreased by 1% (95% CI: 1–2%, p < 0.001), and the risk of developing MAFLD decreased by 1% (95% CI: 0–2%, p = 0.005). There were also significant differences in indicators such as alanine aminotransferase (ALT), gamma-glutamyl transaminase (GGT), and C-reactive protein (CRP) between the MAFLD group and the non-MAFLD group (all p values < 0.001). Conclusions: This study suggests the prevalence of MAFLD and liver fibrosis decreased significantly with the increase in serum 5-mTHF concentration. Full article
(This article belongs to the Section Endocrinology and Clinical Metabolic Research)
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19 pages, 15652 KiB  
Article
Molecular Dynamics Simulations of Plasma–Antifolate Drug Synergy in Cancer Therapy
by Yanxiong Niu, Tong Zhao, Xiaolong Wang, Ying Sun and Yuantao Zhang
Biomolecules 2025, 15(6), 773; https://doi.org/10.3390/biom15060773 - 27 May 2025
Viewed by 504
Abstract
Reactive oxygen species (ROS) generated by cold atmospheric plasma (CAP) cause irreversible damage to cancer cell DNA, RNA, mitochondria, and antioxidant defense systems, leading to apoptosis. Plasma-induced disruption of the antioxidant defense system of cancer cells by cystine uptake via xC antiporter [...] Read more.
Reactive oxygen species (ROS) generated by cold atmospheric plasma (CAP) cause irreversible damage to cancer cell DNA, RNA, mitochondria, and antioxidant defense systems, leading to apoptosis. Plasma-induced disruption of the antioxidant defense system of cancer cells by cystine uptake via xC antiporter has been widely studied, while folate uptake by cancer cells via high expression of hSLC19A1, which generates Nicotinamide Adenine Dinucleotide Phosphate (NADPH) via one-carbon metabolism, is also an important component of the antioxidant defense mechanism of cancer cells. Disrupting folate transport in cancer cells is an important potential pathway for synergizing with pemetrexed (PMX) to induce apoptosis in cancer cells, which is of great research value. In this paper, classical molecular dynamics simulations were employed to study the effect of plasma oxidation of hSLC19A1 on the uptake of 5-Methyltetrahydrofolate (5-MTHF), which is the predominant dietary and circulatory folate, and the antifolate chemotherapeutic agent PMX by cancer cells. The results showed that the channel radius of hSLC19A1 for transporting 5MTHF after oxidation became narrower and the conformation tended to be closed, which was unfavorable for the transport of 5-MTHF; hydrogen bonding and hydrophobic interactions between hSLC19A1 and 5-MTHF decreased, the predicted docking affinity decreased, and the binding energy decreased from −28.023 kcal/mol to −16.866 kcal/mol, while that with PMX was stable around −28 kcal/mol, suggesting that the oxidative modification reduced the binding capacity of hSLC19A1 and 5-MTHF while barely affecting the transport of PMX, which contributed to weakening the antioxidant defense system of cancer cells and synergizing with PMX to induce apoptosis in cancer cells. Our simulations provide theoretical insights for CAP-induced apoptosis in cancer cells at the microscopic level and help promote the further development of cold atmospheric plasma in the field of cancer therapy. Full article
(This article belongs to the Special Issue Advances in Plasma Bioscience and Medicine: 2nd Edition)
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24 pages, 4582 KiB  
Article
Multiple Hits on Cerebral Folate, Tetrahydrobiopterin and Dopamine Metabolism in the Pathophysiology of Parkinson’s Disorder: A Limited Study of Post-Mortem Human Brain Tissues
by Dhruti Balakrishna Doddaballapur, Derren J. Heyes and Jaleel A. Miyan
Metabolites 2025, 15(5), 307; https://doi.org/10.3390/metabo15050307 - 5 May 2025
Viewed by 1052
Abstract
Background: Parkinson’s disorder (PD) affects around 1:500 individuals and is associated with enlarged ventricles and symptoms of normal pressure hydrocephalus (NPH). These features suggest disrupted cerebrospinal fluid (CSF) dynamics and folate metabolism. With L-DOPA treatment showing diminishing benefits over time, there is [...] Read more.
Background: Parkinson’s disorder (PD) affects around 1:500 individuals and is associated with enlarged ventricles and symptoms of normal pressure hydrocephalus (NPH). These features suggest disrupted cerebrospinal fluid (CSF) dynamics and folate metabolism. With L-DOPA treatment showing diminishing benefits over time, there is an urgent need to investigate upstream metabolic disruptions, including folate and tetrahydrobiopterin (BH4) pathways, in post-mortem CSF and brain tissue to understand their roles in PD pathogenesis. Methods: CSF and brain tissue from 20 PD patients (mean age 84 years; 55% male; disease duration 10–30 years) and 20 controls (mean age 82 years; 50% male) were analysed. Western and Dot Blots measured proteins and metabolites, spectroscopic assays assessed enzyme activities, BH4 and Neopterin levels were measured using ELISA, and levels of hydrogen peroxide, used as a proxy for reactive oxygen species, and calcium were quantified using horseradish peroxidase and flame photometry assays, respectively. ClinVar genetic data were analysed for variants in genes encoding key enzymes. Statistical significance was assessed using unpaired t-tests (p < 0.05). Results: All enzymes were significantly reduced in PD compared to controls (p < 0.01) except for methyltetrahydrofolate reductase (MTHFR), which was elevated (p < 0.0001). Enzymes were functional in control but undetectable in PD CSF except tyrosine hydroxylase (TH). BH4 and Neopterin were elevated in PD CSF (p < 0.0001, p < 0.001) but significantly reduced (p < 0.001) or unchanged in tissue. Peroxide was increased in both PD CSF (p < 0.001) and tissue (p < 0.0001) selectively inhibiting TH. Calcium was 40% higher in PD than controls (p < 0.05). No pathogenic variants in enzyme genes were found in ClinVar data searches, suggesting the observed deficiencies are physiological. Conclusions: We identified significant disruptions in folate and BH4 pathways in PD, with enzyme deficiencies, oxidative stress and calcium dysregulation pointing to choroid plexus dysfunction. These findings highlight the choroid plexus and CSF as key players in cerebral metabolism and promote further exploration of these as therapeutic targets to address dopaminergic dysfunction and ventricular enlargement in PD. Full article
(This article belongs to the Special Issue Metabolomics in Neurodegenerative Diseases, 2nd Edition)
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16 pages, 1011 KiB  
Article
Glyphosate Exposure, Oxidative Stress, Mitochondrial Dysfunction, and Mortality Risk in US Adults: Insights from the National Health and Nutrition Examination Survey
by Yu-Wei Fang, Hsuan-Cheng Lin, Chikang Wang and Chien-Yu Lin
Toxics 2025, 13(5), 373; https://doi.org/10.3390/toxics13050373 - 4 May 2025
Viewed by 684
Abstract
Purpose: Glyphosate and glyphosate-based herbicides (GBHs) are widely used across the globe. Experimental research indicates that these herbicides may elevate oxidative stress and impair mitochondrial function. However, the relationship between glyphosate exposure, oxidative stress, and mitochondrial function remains poorly characterized in epidemiological studies. [...] Read more.
Purpose: Glyphosate and glyphosate-based herbicides (GBHs) are widely used across the globe. Experimental research indicates that these herbicides may elevate oxidative stress and impair mitochondrial function. However, the relationship between glyphosate exposure, oxidative stress, and mitochondrial function remains poorly characterized in epidemiological studies. In particular, the role of oxidative stress and mitochondrial function biomarkers in mediating the mortality risk associated with glyphosate exposure in nationally representative populations is not well understood. Approach and Results: In this study, we utilized data from the 2013–2014 National Health and Nutrition Examination Survey (NHANES), encompassing 1464 participants aged 18 years and older. This dataset was linked to mortality records from the National Center for Health Statistics (NCHS), with follow-up data extending through 2019. The primary objective was to examine the associations between urinary glyphosate levels and biomarkers of oxidative stress and mitochondrial function—specifically pyrazino-s-triazine derivative of 4-α-hydroxy-5-methyl-tetrahydrofolate (MeFox) and methylmalonic acid (MMA)—and to evaluate the role of these biomarkers in influencing glyphosate-related mortality outcomes. Results: Urinary glyphosate levels were positively associated with serum MMA and MeFox in weighted multiple linear regression models. For MMA, glyphosate showed significant positive associations in both adjusted models (Model 2: β = 0.061, p = 0.001). Similarly, urinary glyphosate was strongly associated with MeFox in all models (Model 2: β = 0.215, p < 0.001). During a median follow-up of 69.57 months, 116 deaths occurred, including 44 from cardiovascular causes. Glyphosate was not significantly associated with all-cause or cardiovascular mortality in the overall population. However, subgroup analysis revealed significant associations in individuals with higher MeFox levels (≥50th percentile) for all-cause mortality (HR = 1.395, p = 0.027) and borderline associations for cardiovascular mortality (HR = 1.367, p = 0.051). When adjusted for MMA, glyphosate was significantly associated with increased all-cause mortality in participants with MMA levels below the 50th percentile (HR = 2.679, p = 0.001), with a significant interaction between glyphosate and MMA for all-cause (p = 0.002) and cardiovascular mortality (p = 0.038). Conclusions: In this comprehensive analysis of NHANES data, urinary glyphosate levels were associated with biomarkers of oxidative stress and mitochondrial function. While no overall mortality associations were observed, glyphosate exposure was linked to increased all-cause mortality in subgroups with lower MMA or higher MeFox levels. These findings highlight the role of oxidative stress and mitochondrial function in glyphosate-related health risks and the need for further research to identify vulnerable populations. Full article
(This article belongs to the Section Emerging Contaminants)
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27 pages, 2084 KiB  
Review
MTHFR Gene Polymorphisms: A Single Gene with Wide-Ranging Clinical Implications—A Review
by Antoni F. Araszkiewicz, Krzysztof Jańczak, Paweł Wójcik, Bartłomiej Białecki, Szymon Kubiak, Michał Szczechowski and Danuta Januszkiewicz-Lewandowska
Genes 2025, 16(4), 441; https://doi.org/10.3390/genes16040441 - 8 Apr 2025
Cited by 1 | Viewed by 5389
Abstract
The enzyme 5,10-methylenetetrahydrofolate reductase (MTHFR) catalyzes the conversion of 5,10-methylenetetrahydrofolate to 5-methyltetrahydrofolate, a process essential for the methylation of homocysteine to methionine. Polymorphisms in the MTHFR gene can reduce enzyme activity, disrupting the folate cycle and leading to hyperhomocysteinemia. The two most common [...] Read more.
The enzyme 5,10-methylenetetrahydrofolate reductase (MTHFR) catalyzes the conversion of 5,10-methylenetetrahydrofolate to 5-methyltetrahydrofolate, a process essential for the methylation of homocysteine to methionine. Polymorphisms in the MTHFR gene can reduce enzyme activity, disrupting the folate cycle and leading to hyperhomocysteinemia. The two most common polymorphisms associated with this gene are 667C>T (rs1801133) and 1298A>C (rs1801131). Background: This review provides a comprehensive summary of the current knowledge regarding MTHFR polymorphisms, with a particular focus on their potential impact on disease susceptibility. We hope this review will serve as a valuable resource for understanding the significance of MTHFR polymorphisms and their complex relationships with various diseases. Methods: For this review, we prioritized recent evidence, focusing on reviews and meta-analyses published between 2015 and 2025, sourced from PubMed and Google Scholar. Results: We explore the connection between these polymorphisms and a broad spectrum of medical conditions, including cardiovascular diseases and oxidative stress pathology; neurological and psychiatric disorders, such as Autism Spectrum Disorder, Alzheimer’s disease, Schizophrenia, and Major Depressive Disorder; fertility, pregnancy, and neonatal complications, including recurrent pregnancy loss, pre-eclampsia, preterm birth, low birth weight, and neural tube defects; metabolic disorders, such as diabetes mellitus, inflammatory bowel disease, and non-alcoholic fatty liver disease; and oncological conditions, including breast, prostate, and ovarian cancers; as well as leukemia, and autoimmune diseases, particularly rheumatoid arthritis. Conclusions: While some diseases have a well-established association with MTHFR polymorphisms, others require further investigation. Our analysis highlights the crucial role of environmental factors, such as ethnic background and dietary folate intake, in influencing study outcomes. Full article
(This article belongs to the Section Molecular Genetics and Genomics)
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10 pages, 370 KiB  
Article
A Clinical and Genetic Evaluation of Cases with Folate Receptor α Gene Mutation: A Case Series from Türkiye
by Abdurrahman Akgun and Ibrahim Tas
Diagnostics 2025, 15(7), 892; https://doi.org/10.3390/diagnostics15070892 - 1 Apr 2025
Viewed by 794
Abstract
Background/Objectives: Cerebral folate transporter deficiency is characterized by pauses and regression in general development stages, with ataxia, choreoathetoid movements, and myoclonic epilepsy generally resistant to treatment. The aim of this study was to comprehensively evaluate cases followed up in two centres in [...] Read more.
Background/Objectives: Cerebral folate transporter deficiency is characterized by pauses and regression in general development stages, with ataxia, choreoathetoid movements, and myoclonic epilepsy generally resistant to treatment. The aim of this study was to comprehensively evaluate cases followed up in two centres in Türkiye for a diagnosis of folate receptor-α deficiency. Methods: The study included nine cases from six different families. Results: The patients comprised 22.2% males and there was parental consanguinity in 88.9% of cases. The mean age at which complaints were first noticed was 3.7 years, and the age of definitive diagnosis was 10.4 years. The most frequently seen first complaints were febrile convulsions and attention deficit-hyperactivity-learning difficulties. The diagnosis most commonly made before the definitive diagnosis was epilepsy, and the first seizure occurred at a mean of 5.2 years. On cranial imaging, white matter involvement, cerebellar atrophy and cerebral atrophy were determined most often. Definitive diagnosis was established solely through clinical findings and genetic analysis. Three different variants in the FOLR1 gene were determined. Treatment with folinic acid at a dose of 5.2 mg/kg/day of PO was started at the age of 9.8 years on average, and intravenous folinate was started at different doses. Conclusions: This study stands out as one of the largest case series in the literature and identifies a previously unreported novel variant. Our study suggests that FOLR1-related CFD should be considered in cases with febrile convulsions, developmental delay, ataxia, autism spectrum disorder, acquired microcephaly, and MRI findings of white matter involvement and cerebellar atrophy. Due to an asymptomatic early period, CFD diagnosis may be delayed, and treatment after symptom onset may be less effective. Incorporating FOLR1 gene analysis into newborn screening programmes could facilitate early diagnosis and treatment. It is thought that the application of vagus nerve stimulation, in addition to folinic acid and anticonvulsant drug treatment, could be effective in seizure control. Full article
(This article belongs to the Section Pathology and Molecular Diagnostics)
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15 pages, 4537 KiB  
Article
Construction of a Cofactor Self-Sufficient Enzyme Cascade System Coupled with Microenvironmental Engineering for Efficient Biosynthesis of Tetrahydrofolate and Its Derivative of L-5-Methyltetrahydrofolate
by Ziting Yan, Lisha Qin, Ruirui Qin, Xin Wang and Kequan Chen
Catalysts 2025, 15(3), 235; https://doi.org/10.3390/catal15030235 - 28 Feb 2025
Viewed by 1014
Abstract
Tetrahydrofolate (THF), the biologically active form of folate, serves as a crucial carrier of one-carbon units essential for synthesizing cellular components such as amino acids and purine nucleotides in vivo. It also acts as an important precursor for the production of pharmaceuticals, including [...] Read more.
Tetrahydrofolate (THF), the biologically active form of folate, serves as a crucial carrier of one-carbon units essential for synthesizing cellular components such as amino acids and purine nucleotides in vivo. It also acts as an important precursor for the production of pharmaceuticals, including folinate and L-5-methyltetrahydrofolate (L-5-MTHF). In this study, we developed an efficient enzyme cascade system for the production tetrahydrofolate from folate, incorporating NADPH recycling, and explored its application in the synthesis of L-5-MTHF, a derivative of tetrahydrofolate. To achieve this, we first screened dihydrofolate reductases (DHFRs) from various organisms, identifying SmDHFR from Serratia marcescens as the enzyme with the highest catalytic activity. We then conducted a comparative analysis of formate dehydrogenases (FDHs) from different sources, successfully establishing an NADPH recycling system. To further enhance biocatalytic efficiency, we optimized key reaction parameters, including temperature, pH, enzyme ratio, and substrate concentration. To address the challenge of pH mismatch in dual-enzyme reactions, we employed an enzymatic microenvironment regulation strategy. This involved covalently conjugating SmDHFR with a superfolder green fluorescent protein mutant carrying 30 surface negative charges (−30sfGFP), using the SpyCatcher/SpyTag system. This modification resulted in a 2.16-fold increase in tetrahydrofolate production, achieving a final yield of 4223.4 µM. Finally, we extended the application of this tetrahydrofolate synthesis system to establish an enzyme cascade for L-5-MTHF production with NADH recycling. By incorporating methylenetetrahydrofolate reductase (MTHFR), we successfully produced 389.8 μM of L-5-MTHF from folate and formaldehyde. This work provides a novel and efficient pathway for the biosynthesis of L-5-MTHF and highlights the potential of enzyme cascade systems in the production of tetrahydrofolate-derived compounds. Full article
(This article belongs to the Special Issue Enzyme Engineering—the Core of Biocatalysis)
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12 pages, 906 KiB  
Article
Different Chemical Forms of Thiamine, Riboflavin, and Folate in Human Milk as a Function of Lactation Stages—A Cohort Study on Breastfeeding Women from Beijing
by Ye Wang, Xinxin Xing, Xiangnan Ren, Shan Jiang, Zhenyu Yang and Jianqiang Lai
Nutrients 2025, 17(4), 624; https://doi.org/10.3390/nu17040624 - 9 Feb 2025
Viewed by 1177
Abstract
Background: The function and bioavailability of water-soluble vitamins in human milk (HM) is contingent upon their specific molecular configurations. This study aims to investigate the concentrations of different forms of thiamine, riboflavin, and folate in HM and to elucidate the temporal variations of [...] Read more.
Background: The function and bioavailability of water-soluble vitamins in human milk (HM) is contingent upon their specific molecular configurations. This study aims to investigate the concentrations of different forms of thiamine, riboflavin, and folate in HM and to elucidate the temporal variations of these nutrients across different stages of lactation. Methods: A cohort of 35 healthy mother–infant pairs from Beijing was recruited, and 214 HM samples were collected. The concentrations of water-soluble vitamins in these samples were analyzed using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). A mixed linear regression model was employed to examine the relationship between HM vitamin levels and lactation stages. Results: This study analyzed the concentrations of free thiamine, thiamine monophosphate (TMP), thiamine pyrophosphate (TPP), free riboflavin, flavin adenine dinucleotide (FAD), flavin mononucleotide (FMN), 5-methyl-tetrahydrofolate (5-MTHF), tetrahydrofolate (THF), 5-formyl-tetrahydrofolate (5-fTHF), 5,10-methenyl-tetrahydrofolate (5,10-MTHF), and unmetabolized folic acid (UMFA) at various lactation stages (0–7 days, 15 days, 30 days, 60 days, 90 days, 120 days, 150 days, and 180 days). Free thiamine concentrations increased from colostrum to 180 days, while total thiamine rose during the first month and then stabilized. Free and total riboflavin levels remained relatively constant throughout lactation. Free and total folate concentrations peaked at 90 days and subsequently declined. Significant correlations were observed between follow-up time and changes in free thiamine, free folate, and total folate concentrations over 180 days. Conclusions: This study provides detailed data on the concentrations and trends of free and total thiamine, riboflavin, and folate in HM from 0 to 180 days postpartum, highlighting the dynamic nature of vitamin concentrations in HM. No deficiencies in these HM vitamins were detected in the surveyed population. Future further research will be conducted to reveal the correlation between different forms of water-soluble vitamins in HM and dietary factors. Full article
(This article belongs to the Section Pediatric Nutrition)
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40 pages, 8055 KiB  
Article
Exertional Exhaustion (Post-Exertional Malaise, PEM) Evaluated by the Effects of Exercise on Cerebrospinal Fluid Metabolomics–Lipidomics and Serine Pathway in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome
by James N. Baraniuk
Int. J. Mol. Sci. 2025, 26(3), 1282; https://doi.org/10.3390/ijms26031282 - 1 Feb 2025
Cited by 2 | Viewed by 23440
Abstract
Post-exertional malaise (PEM) is a defining condition of myalgic encephalomyelitis (ME/CFS). The concept requires that a provocation causes disabling limitation of cognitive and functional effort (“fatigue”) that does not respond to rest. Cerebrospinal fluid was examined as a proxy for brain metabolite and [...] Read more.
Post-exertional malaise (PEM) is a defining condition of myalgic encephalomyelitis (ME/CFS). The concept requires that a provocation causes disabling limitation of cognitive and functional effort (“fatigue”) that does not respond to rest. Cerebrospinal fluid was examined as a proxy for brain metabolite and lipid flux and to provide objective evidence of pathophysiological dysfunction. Two cohorts of ME/CFS and sedentary control subjects had lumbar punctures at baseline (non-exercise) or after submaximal exercise (post-exercise). Cerebrospinal fluid metabolites and lipids were quantified by targeted Biocrates mass spectrometry methods. Significant differences between ME/CFS and control, non-exercise vs. post-exercise, and by gender were examined by multivariate general linear regression and Bayesian regression methods. Differences were found at baseline between ME/CFS and control groups indicating disease-related pathologies, and between non-exercise and post-exercise groups implicating PEM-related pathologies. A new, novel finding was elevated serine and its derivatives sarcosine and phospholipids with a decrease in 5-methyltetrahydrofolate (5MTHF), which suggests general dysfunction of folate and one-carbon metabolism in ME/CFS. Exercise led to consumption of lipids in ME/CFS and controls while metabolites were consumed in ME/CFS but generated in controls. In general, the frequentist and Bayesian analyses generated complementary but not identical sets of analytes that matched the metabolic modules and pathway analysis. Cerebrospinal fluid is unique because it samples the choroid plexus, brain interstitial fluid, and cells of the brain parenchyma. The quantitative outcomes were placed into the context of the cell danger response hypothesis to explain shifts in serine and phospholipid synthesis; folate and one-carbon metabolism that affect sarcosine, creatine, purines, and thymidylate; aromatic and anaplerotic amino acids; glucose, TCA cycle, trans-aconitate, and coenzyme A in energy metabolism; and vitamin activities that may be altered by exertion. The metabolic and phospholipid profiles suggest the additional hypothesis that white matter dysfunction may contribute to the cognitive dysfunction in ME/CFS. Full article
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15 pages, 3173 KiB  
Article
Folic Acid and Methyltetrahydrofolate Supplementation in the Mthfr677C>T Mouse Model with Hepatic Steatosis
by Karen E. Christensen, Marie-Lou Faquette, Daniel Leclerc, Vafa Keser, Yan Luan, Jeanna L. Bennett-Firmin, Olga V. Malysheva, Alaina M. Reagan, Gareth R. Howell, Marie A. Caudill, Teodoro Bottiglieri and Rima Rozen
Nutrients 2025, 17(1), 82; https://doi.org/10.3390/nu17010082 - 28 Dec 2024
Cited by 2 | Viewed by 1775
Abstract
Background/Objectives: The MTHFR677C>T gene variant results in a thermolabile MTHFR enzyme associated with elevated plasma homocysteine in TT individuals. Health risks associated with the TT genotype may be modified by dietary and supplemental folate intake. Supplementation with methyltetrahydrofolate (methylTHF) may be preferable [...] Read more.
Background/Objectives: The MTHFR677C>T gene variant results in a thermolabile MTHFR enzyme associated with elevated plasma homocysteine in TT individuals. Health risks associated with the TT genotype may be modified by dietary and supplemental folate intake. Supplementation with methyltetrahydrofolate (methylTHF) may be preferable to folic acid because it is the MTHFR product, and does not require reduction by DHFR to enter one-carbon folate metabolism. In the Mthfr677C>T mouse model for this variant, female 677TT (TT) mice have an increased incidence of hepatic steatosis. The objective of this study was to compare the effects of methylTHF and folic acid supplementation on hepatic steatosis and one-carbon metabolism in this model. Methods: Male and female C57BL/6J 677CC (CC) and TT mice were fed control (CD), 5xmethylTHF-supplemented (MFSD), or 5xfolic-acid-supplemented (FASD) diets for 4 months. Liver sections were assessed for steatosis by Oil Red O staining. One-carbon metabolites were measured in the liver and plasma. MTHFR protein expression was evaluated in the liver. Results: MFSD had no significant effect on plasma homocysteine, liver SAM/SAH ratios, or hepatic steatosis in males or females as compared to CD. MTHFR protein increased in MFSD TT female liver, but remained <50% of the CC. FASD had no effect on plasma homocysteine but it decreased the liver MTHFR protein and SAM/SAH ratios, and increased hepatic steatosis in CC females. Conclusions: MethylTHF and folic acid supplementation had limited benefits for TT mice, while folic acid supplementation had negative effects on CC females. Further investigation is required to determine if these effects are relevant in humans. Full article
(This article belongs to the Section Micronutrients and Human Health)
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19 pages, 4317 KiB  
Article
Comparison of Interactions Between Soy Protein Isolate and Three Folate Molecules: Effect on the Stabilization, Degradation, and Oxidization of Folates and Protein
by Linlin He, Yuqian Yan, Dandan Song, Shuangfeng Li, Yanna Zhao, Zhuang Ding and Zhengping Wang
Foods 2024, 13(24), 4033; https://doi.org/10.3390/foods13244033 - 13 Dec 2024
Viewed by 1380
Abstract
This study selected three approved folate sources—folic acid (FA), L-5-methyltetrahydrofolate (MTFA), and calcium 5-methyltetrahydrofolate (CMTFA)—to explore their interaction mechanisms with soy protein isolate (SPI) through spectrofluorometric analysis and molecular docking simulations. We investigated how these interactions influence the structural and physicochemical stability of [...] Read more.
This study selected three approved folate sources—folic acid (FA), L-5-methyltetrahydrofolate (MTFA), and calcium 5-methyltetrahydrofolate (CMTFA)—to explore their interaction mechanisms with soy protein isolate (SPI) through spectrofluorometric analysis and molecular docking simulations. We investigated how these interactions influence the structural and physicochemical stability of folates and SPI. Three folates spontaneously bound to SPI, forming complexes, resulting in a decrease of approximately 30 kJ·mol−1 in Gibbs free energy and an association constant (Ka) of 105 L·mol−1. The thermodynamic parameters and molecular docking study revealed the unique binding mechanisms of FA and MTFA with SPI. FA’s planar pteridine ring and conjugated double bonds facilitate hydrophobic interactions, whereas MTFA’s reduced ring structure and additional polar groups strengthen hydrogen bonding. Although the formation of SPI–folate complexes did not result in substantial alterations to the SPI structure, their binding has the potential to enhance both the physical and thermal stability of the protein by stabilizing its conformation. Notably, compared with free FA, the FA-SPI complexes significantly enhanced FA’s stability, exhibiting 71.1 ± 1.2% stability under light conditions after 9 days and 63.2 ± 2.6% stability in the dark after 60 days. In contrast, no similar effect was observed for MTFA. This discrepancy can be ascribed to the distinct degradation pathways of the Fa and MTFA molecules. This study offers both theoretical and experimental insights into the development of folate-loaded delivery systems utilizing SPI as a matrix. Full article
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20 pages, 529 KiB  
Article
Comparative Study on the Nutritional Quality of Peanut in Saline and Non-Saline Land
by Yimin Zhang, Yanmi Li, Xiao Ren, Jieying Gao, Yuchen Wang and Dazhou Zhu
Foods 2024, 13(23), 3751; https://doi.org/10.3390/foods13233751 - 23 Nov 2024
Cited by 2 | Viewed by 1193
Abstract
Saline soils, as a special class of soil types, have unique physicochemical properties that have far-reaching effects on crop growth and quality characteristics. In order to better develop saline soils as a reserve resource, it is particularly important to exploit the potential of [...] Read more.
Saline soils, as a special class of soil types, have unique physicochemical properties that have far-reaching effects on crop growth and quality characteristics. In order to better develop saline soils as a reserve resource, it is particularly important to exploit the potential of saline crops. Peanut, as one of the important crops in saline soils, can have different quality characteristics depending on the differences in soil salinity and alkalinity, as well as growing conditions. In this study, we compared the nutritional quality and functional composition of five peanut varieties grown in coastal saline soils, with the same varieties grown in non-saline soils in similar areas. The results showed significant differences (p<0.05) between saline and non-saline peanuts in the contents of ash, zinc, phosphorus, β-VE, Cis-11-eicosatetraenoic acid, palmitoleic acid, linolenic acid, and total antioxidant removal capacity, whereby the former was higher than the latter by 0.12 g/100 g, 4.1 mg/kg, 321 mg/kg, 8.98 μg/g, 0.36%, 0.01%, and 0.01%, respectively, and the total antioxidant capacity was lower than that of the latter by 9.18 μg Trolxo/g of fresh weight. Sodium element and superoxide dismutase (SOD) activity contents were extremely significantly (p<0.01) different in peanuts grown in both land types, where the former was higher than the latter by 261.9 mg/kg and 285 U/g, respectively. Water, fat, protein, calcium, copper, iron, potassium, magnesium, manganese, Vc, α-VE, total VE, VB3, 5-methyl-tetrahydrofolate, 5-formyl-tetrahydrofolate, total phenols, total flavonoids, ABTS free radical scavenging capacity, DPPH free radical scavenging capacity, fatty acids (except for Cis-11-eicosapentaenoic acid, palmitoleic acid, and linolenic acid), phytosterols, and guanines showed no significant differences (p<0.01). To sum up, the origin and soil environment have an effect on the quality of peanuts. These results also provide a scientific basis for the quality assessment of peanuts in saline soil. Full article
(This article belongs to the Section Food Quality and Safety)
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17 pages, 1198 KiB  
Review
Supplementation with Folic Acid or 5-Methyltetrahydrofolate and Prevention of Neural Tube Defects: An Evidence-Based Narrative Review
by María de Lourdes Samaniego-Vaesken, Carmen Morais-Moreno, Alejandra Carretero-Krug, Ana María Puga, Ana María Montero-Bravo, Teresa Partearroyo and Varela-Moreiras Gregorio
Nutrients 2024, 16(18), 3154; https://doi.org/10.3390/nu16183154 - 18 Sep 2024
Cited by 3 | Viewed by 11593
Abstract
Background: Folic acid (FA), which in its chemical form is pteroylglutamic acid, is the fully oxidised, water-soluble, monoglutamic form of vitamin B9. This compound is part of the folate group but with higher bioavailability, and it is found in vitamin supplements and fortified [...] Read more.
Background: Folic acid (FA), which in its chemical form is pteroylglutamic acid, is the fully oxidised, water-soluble, monoglutamic form of vitamin B9. This compound is part of the folate group but with higher bioavailability, and it is found in vitamin supplements and fortified foods and drugs. Folate metabolism is complex and associated with various metabolic pathways, all of which confer protection on the cell and allow its survival. Methods: We conducted a non-systematic search of articles published in English and Spanish including controlled trials, cohort studies, systematic re-views, and meta-analyses were included, as well as key studies in animal models related to pharmacokinetic studies. Search terms encompassed: “folic acid”, “folates”, “5-metyltetrahydrofolate”, “5-MTHF”, “neural tube defects”, “supplementation”, “fortification”, AND “homocysteine” Results: A crucial role demonstrated for FA is to help prevent neural tube defects (NTDs). However, more studies are definitely still needed to establish 5-MTHF as a safe and effective therapeutic approach comparable with FA. Moreover, there is a lack of clinical studies that evaluate the efficacy of 5-MTHF supplementation in the prevention of NTDs. The present evidence-based narrative review discusses differences between FA and 5-MTHF in terms of structure, metabolism, bioavailability, clinical efficacy, and safety. Conclusions: Despite the potential value of 5-MTHF as an alternative to FA, clinical studies would be urgently needed to support the efficacy, dosage, timing, and/or safety of its use as a supplement. Full article
(This article belongs to the Section Nutrition in Women)
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18 pages, 2851 KiB  
Article
Non-Covalent Interaction of Folic Acid and 5-Methyltetrahydrofolate with Caseinates Improves the Folates Stability Studied by Multi-Spectroscopic Analysis and Molecular Docking
by Linlin He, Yuqian Yan, Gang Zhang, Yanna Zhao, Fa Zhao, Zhuang Ding and Zhengping Wang
Foods 2024, 13(17), 2756; https://doi.org/10.3390/foods13172756 - 29 Aug 2024
Cited by 1 | Viewed by 1291
Abstract
Folates, a crucial B-group vitamin, serve as a significant functional food supplement. Nevertheless, considerable obstacles persist in improving folates stability in liquid products. In this study, folic acid (FA) and 5-methyltetrahydrofolate (MTFA), two approved sources of folates, were encapsulated with sodium caseinate (NaCas) [...] Read more.
Folates, a crucial B-group vitamin, serve as a significant functional food supplement. Nevertheless, considerable obstacles persist in improving folates stability in liquid products. In this study, folic acid (FA) and 5-methyltetrahydrofolate (MTFA), two approved sources of folates, were encapsulated with sodium caseinate (NaCas) to enhance their stability. The protective effect of NaCas on folate molecules was investigated using experimental and computational methods. Meanwhile, the influence of divalent calcium ion (Ca2+) on the properties of the NaCas-MTFA complex was examined to evaluate the potential application of calcium 5-methyltetrahydrofolate (CaMTFA). Fluorescence tests showed both folates had static quenching behavior and bound to NaCas with a binding constant of 104–105 M−1. Hydrophobic interactions were crucial in NaCas-FA complex formation, while hydrogen bonding drove NaCas-MTFA binding. The encapsulation of caseinate notably slowed down the degradation of folates under both light and dark conditions. Moreover, the addition of a low concentration of Ca2+ did not adversely impact the binding mechanism of the NaCas-MTFA complex or the degradation curve of MTFA. The results of this study could serve as a valuable resource for the utilization of caseinates in incorporating folates, specifically MTFA, in the creation of natural liquid dietary supplements. Full article
(This article belongs to the Section Food Engineering and Technology)
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