RESUMEN
BACKGROUND: Folates are a family of B9 vitamins essential for normal growth and development in the central nervous system (CNS). Transport of folates is mediated by three major transport proteins: folate receptor alpha (FRα), proton-coupled folate transporter (PCFT), and reduced folate carrier (RFC). Brain folate uptake occurs at the choroid plexus (CP) epithelium through coordinated actions of FRα and PCFT, or directly into brain parenchyma at the vascular blood-brain barrier (BBB), mediated by RFC. Impaired folate transport can occur due to loss of function mutations in FRα or PCFT, resulting in suboptimal CSF folate levels. Our previous reports have demonstrated RFC upregulation by nuclear respiratory factor-1 (NRF-1) once activated by the natural compound pyrroloquinoline quinone (PQQ). More recently, we have identified folate transporter localization at the arachnoid barrier (AB). The purpose of the present study was to further characterize folate transporters localization and function in AB cells, as well as their regulation by NRF-1/PGC-1α signaling and folate deficiency. METHODS: In immortalized mouse AB cells, polarized localization of RFC and PCFT was assessed by immunocytochemical analysis, with RFC and PCFT functionality examined with transport assays. The effects of PQQ treatment on changes in RFC functional expression were also investigated. Mouse AB cells grown in folate-deficient conditions were assessed for changes in gene expression of the folate transporters, and other key transporters and tight junction proteins. RESULTS: Immunocytochemical analysis revealed apical localization of RFC at the mouse AB epithelium, with PCFT localized on the basolateral side and within intracellular compartments. PQQ led to significant increases in RFC functional expression, mediated by activation of the NRF-1/PGC-1α signalling cascade. Folate deficiency led to significant increases in expression of RFC, MRP3, P-gp, GLUT1 and the tight junction protein claudin-5. CONCLUSION: These results uncover the polarized expression of RFC and PCFT at the AB, with induction of RFC functional expression by activation of the NRF-1/PGC-1α signalling pathway and folate deficiency. These results suggest that the AB may contribute to the flow of folates into the CSF, representing an additional pathway when folate transport at the CP is impaired.
Asunto(s)
Ácido Fólico , Transportador de Folato Acoplado a Protón , Animales , Ácido Fólico/metabolismo , Ratones , Transportador de Folato Acoplado a Protón/metabolismo , Transportador de Folato Acoplado a Protón/genética , Receptor 1 de Folato/metabolismo , Receptor 1 de Folato/genética , Transporte Biológico/fisiología , Proteína Portadora de Folato Reducido/metabolismo , Proteína Portadora de Folato Reducido/genética , Deficiencia de Ácido Fólico/metabolismo , Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/efectos de los fármacos , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Plexo Coroideo/metabolismoRESUMEN
Folate is a vitamin required for cell growth and is present in fortified foods in the form of folic acid to prevent congenital abnormalities. The impact of low-folate status on life-long health is poorly understood. We found that limiting folate levels with the folate antagonist methotrexate increased the lifespan of yeast and worms. We then restricted folate intake in aged mice and measured various health metrics, metabolites, and gene expression signatures. Limiting folate intake decreased anabolic biosynthetic processes in mice and enhanced metabolic plasticity. Despite reduced serum folate levels in mice with limited folic acid intake, these animals maintained their weight and adiposity late in life, and we did not observe adverse health outcomes. These results argue that the effectiveness of folate dietary interventions may vary depending on an individual's age and sex. A higher folate intake is advantageous during the early stages of life to support cell divisions needed for proper development. However, a lower folate intake later in life may result in healthier aging.
Asunto(s)
Ácido Fólico , Longevidad , Animales , Ácido Fólico/administración & dosificación , Ácido Fólico/metabolismo , Ratones , Masculino , Femenino , Envejecimiento/metabolismo , Dieta/métodos , Ratones Endogámicos C57BL , Metotrexato/farmacología , Deficiencia de Ácido Fólico/metabolismo , Caenorhabditis elegans , Saccharomyces cerevisiae/metabolismoRESUMEN
BACKGROUND: Metabolic associated fatty liver disease (MAFLD), a prevalent liver disorder affecting one-third of the global population, encompasses a spectrum ranging from fatty liver to severe hepatic steatosis. Both genetic and lifestyle factors, particularly diet and nutrition, contribute to its etiology. Folate deficiency, a frequently encountered type of malnutrition, has been associated with the pathogenesis of MAFLD and shown to impact lipid deposition. However, the underlying mechanisms of this relationship remain incompletely understood. We investigated the impact of disturbed folate-mediated one-carbon metabolism (OCM) on hepatic lipid metabolism both in vitro using human hepatoma cells and in vivo using transgenic fluorescent zebrafish displaying extent-, stage-, and duration-controllable folate deficiency upon induction. RESULTS: Disturbed folate-mediated one-carbon metabolism, either by inducing folate deficiency or adding anti-folate drug, compromises autophagy and causes lipid accumulation in liver cells. Disturbed folate status down-regulates cathepsin L, a key enzyme involved in autophagy, through inhibiting mTOR signaling. Interfered mitochondrial biology, including mitochondria relocation and increased fusion-fission dynamics, also occurs in folate-deficient hepatocytes. Folate supplementation effectively mitigated the impaired autophagy and lipid accumulation caused by the inhibition of cathepsin L activity, even when the inhibition was not directly related to folate deficiency. CONCLUSIONS: Disruption of folate-mediated OCM diminishes cathepsin L expression and impedes autophagy via mTOR signaling, leading to lipid accumulation within hepatocytes. These findings underscore the crucial role of folate in modulating autophagic processes and regulating lipid metabolism in the liver.
Asunto(s)
Autofagia , Ácido Fólico , Hepatocitos , Homeostasis , Metabolismo de los Lípidos , Pez Cebra , Autofagia/fisiología , Ácido Fólico/metabolismo , Humanos , Hepatocitos/metabolismo , Animales , Deficiencia de Ácido Fólico/metabolismoRESUMEN
Folate is a micronutrient essential for DNA synthesis, cell division, fetal growth and development. Folate deficiency leads to genomic instability. Inadequate intake of folate during conception may lead to neural tube defects (NTDs) in the offspring. Folate influences the DNA methylation, histone methylation and homocysteine mediated gene methylation. DNA methylation influences the expression of microRNAs (miRNAs). Folate deficiency may be associated with miRNAs misregulation leading to NTDs. Mitochondrial epigenetics and folate metabolism has proved to be involved in embryogenesis and neural tube development. Folate related genetic variants also cause the occurrence of NTDs. Unmetabolized excessive folate may affect health adversely. Hence estimation of folate levels in the blood plays an important role in high-risk cases.
Asunto(s)
Deficiencia de Ácido Fólico , MicroARNs , Defectos del Tubo Neural , Humanos , Ácido Fólico , Defectos del Tubo Neural/genética , Defectos del Tubo Neural/metabolismo , Deficiencia de Ácido Fólico/complicaciones , Deficiencia de Ácido Fólico/genética , Deficiencia de Ácido Fólico/metabolismo , Epigénesis Genética , Metilación de ADN , MicroARNs/genética , Tubo Neural/metabolismoRESUMEN
SCOPE: Disturbances in one-carbon metabolism contribute to nonalcoholic fatty liver disease (NAFLD) which encompasses steatosis, steatohepatitis, fibrosis, and cirrhosis. The goal is to examine impact of folate deficiency and the Mthfr677C >T variant on NAFLD. METHODS AND RESULTS: This study uses the new Mthfr677C >T mouse model for the human MTHFR677C >T variant. Mthfr677CC and Mthfr677TT mice were fed control diet (CD) or folate-deficient (FD) diets for 4 months. FD and Mthfr677TT alter choline/methyl metabolites in liver and/or plasma (decreased S-adenosylmethionine (SAM):S-adenosylhomocysteine (SAH) ratio, methyltetrahydrofolate, and betaine; increased homocysteine [Hcy]). FD, with contribution from Mthfr677TT, provokes fibrosis in males. Studies of normal livers reveal alterations in plasma markers and gene expression that suggest an underlying predisposition to fibrosis induced by FD and/or Mthfr677TT in males. These changes are absent or reverse in females, consistent with the sex disparity of fibrosis. Sex-based differences in methylation potential, betaine, sphingomyelin, and trimethylamine-N-oxide (TMAO) levels may prevent fibrogenesis in females. In contrast, Mthfr677TT alters choline metabolism, dysregulates expression of lipid metabolism genes, and promotes steatosis in females. CONCLUSION: This study suggests that folate deficiency predisposes males to fibrosis, which is exacerbated by Mthfr677TT, whereas Mthfr677TT predisposes females to steatosis, and reveal novel contributory mechanisms for these NAFLD-related disorders.
Asunto(s)
Deficiencia de Ácido Fólico , Metilenotetrahidrofolato Reductasa (NADPH2) , Enfermedad del Hígado Graso no Alcohólico , Animales , Femenino , Humanos , Masculino , Ratones , Betaína , Colina/metabolismo , Ácido Fólico , Deficiencia de Ácido Fólico/metabolismo , Genotipo , Homocisteína , Cirrosis Hepática/etiología , Enfermedad del Hígado Graso no Alcohólico/etiología , S-AdenosilmetioninaRESUMEN
Folate is essential for the normal growth and development of the fetus. Folic acid supplementation during the fetal period affects postnatal brain development and reduces the incidence of mental disorders in animal and human studies. However, the association between folate deficiency (FD) during pregnancy and developmental disorders in children remains poorly understood. In this study, we investigated whether prenatal FD is associated with neurodevelopmental disorders in offspring. ICR mice were fed a control diet (2 mg folic acid/kg diet) or a folate-deficient diet (0.3 mg folic acid/kg diet) from embryonic day 1 until parturition. We evaluated locomotor activity, anxiety, grooming, sociability and learning memory in male offspring at 7-10 weeks of age. No differences were found in locomotor activity or anxiety in the open field test, nor in grooming time in the self-grooming test. However, sociability, spatial memory, and novel object recognition were impaired in the FD mice compared with control offspring. Furthermore, we measured protein expression levels of the NMDA and AMPA receptors, as well as PSD-95 and the GABA-synthesizing enzymes GAD65/67 in the frontal cortex and hippocampus. In FD mice, expression levels of AMPA receptor 1 and PSD-95 in both regions were reduced compared with control mice. Moreover, NMDA receptor subunit 2B and GAD65/67 were significantly downregulated in the frontal cortex of prenatal FD mice compared with the controls. Collectively, these findings suggest that prenatal FD causes behavioral deficits together with a reduction in synaptic protein levels in the frontal cortex and hippocampus.
Asunto(s)
Deficiencia de Ácido Fólico , Efectos Tardíos de la Exposición Prenatal , Humanos , Embarazo , Femenino , Niño , Animales , Masculino , Ratones , Ácido Fólico/metabolismo , Ratones Endogámicos ICR , Deficiencia de Ácido Fólico/complicaciones , Deficiencia de Ácido Fólico/metabolismo , Dieta , Encéfalo/metabolismo , Efectos Tardíos de la Exposición Prenatal/metabolismoRESUMEN
Folate deficiency contribute to neural tube defects (NTDs) which could be rescued by folate supplementation. However, the underlying mechanisms are still not fully understood. Besides, there is considerable controversy concerning the forms of folate used for supplementation. To address this controversy, we prepared culture medium with different forms of folate, folic acid (FA), and 5-methyltetrahydrofolate (5mTHF), at concentrations of 5 µM, 500 nM, 50 nM, and folate free, respectively. Mouse embryonic fibroblasts (MEFs) were treated with different folates continuously for three passages, and cell proliferation and F-actin were monitored. We determined that compared to 5mTHF, FA showed stronger effects on promoting cell proliferation and F-actin formation. We also found that FOLR1 protein level was positively regulated by folate concentration and the non-canonical Wnt/planar cell polarity (PCP) pathway signaling was significantly enriched among different folate conditions in RNA-sequencing analyses. We demonstrated for the first time that FOLR1 could promote the transcription of Vangl2, one of PCP core genes. The transcription of Vangl2 was down-regulated under folate-deficient condition, which resulted in a decrease in PCP activity and F-actin formation. In summary, we identified a distinct advantage of FA in cell proliferation and F-actin formation over 5mTHF, as well as demonstrating that FOLR1 could promote transcription of Vangl2 and provide a new mechanism by which folate deficiency can contribute to the etiology of NTDs.
Asunto(s)
Deficiencia de Ácido Fólico , Defectos del Tubo Neural , Animales , Ratones , Ácido Fólico/metabolismo , Actinas/metabolismo , Receptor 1 de Folato/genética , Receptor 1 de Folato/metabolismo , Polaridad Celular/genética , Fibroblastos/metabolismo , Vía de Señalización Wnt , Defectos del Tubo Neural/genética , Defectos del Tubo Neural/metabolismo , Deficiencia de Ácido Fólico/metabolismoRESUMEN
Research demonstrated that folate deficiency in either the mother or father could impact the biological functions of the offspring's of neural cells. Folate deficiency can also impair the methionine cycle, thus contributing to the conversion of S-adenosylmethionine (SAM) to S-adenosylhomocysteine (SAH), which could potentially cause damage to the central nervous system. The study focused on the effect of parental folate deficiency on neural cell apoptosis in offspring neonatal rats and whether it is mediated by the levels of SAM and SAH in brains. The experimental design was conducted by feeding female and male Sprague Dawley (SD) rats with either folate-deficient or folate-normal diets, sacrificing the offspring within 24 h and isolating their brain tissue. Rats were divided into four groups: the maternal-folate-deficient and paternal-folate-deficient (D-D) group; the maternal-folate-deficient and paternal-folate-normal (D-N) group; the maternal-folate-normal and paternal-folate-deficient (N-D) group; and the maternal-folate-normal and paternal-folate-normal (N-N) group. There was down-regulation of B-cell lymphoma 2 (Bcl-2) expression, up-regulation of Bcl-2-associated X protein (Bax) and Caspase-3 expression of neural cells, and pathological changes in the brain ultrastructure, as well as decreased SAM levels, increased SAH levels, and a decreased SAM/SAH ratio in the rat fetal brain via parental folate deficiency. In conclusion, parental folate deficiency could induce the apoptosis of neural cells in neonatal offspring rats, while biparental folate deficiency had the greatest effect on offspring, and the unilateral effect was greater in mothers than in fathers. This process may be mediated by the levels of SAM and SAH in the rat fetal brain.
Asunto(s)
Deficiencia de Ácido Fólico , Ratas , Animales , Masculino , Femenino , Animales Recién Nacidos , Proteína X Asociada a bcl-2/genética , Caspasa 3 , Ratas Sprague-Dawley , Deficiencia de Ácido Fólico/metabolismo , Ácido Fólico , Apoptosis/fisiología , S-Adenosilmetionina/metabolismoRESUMEN
Folate, as the initial substrate in one-carbon metabolism, is involved in the synthesis of important substances such as DNA, RNA, and protein. Folate deficiency (FD) is associated with male subfertility and impaired spermatogenesis, yet the underlying mechanisms are poorly understood. In the present study, we established an animal model of FD to investigate the effect of FD on spermatogenesis. GC-1 spermatogonia were used as a model to investigate the effect of FD on proliferation, viability, and chromosomal instability (CIN). Furthermore, we explored the expression of core genes and proteins of spindle assembly checkpoint (SAC), a signaling cascade ensuring accurate chromosome segregation and preventing CIN during mitosis. Cells were maintained in medium containing 0, 20, 200, or 2000 nM folate for 14 days. CIN was measured by using a cytokinesis-blocked micronucleus cytome assay. We found that sperm counts decreased significantly (p < 0.001) and the rate of sperm with defects in the head increased significantly (p < 0.05) in FD diet mice. We also found, relative to the folate-sufficient conditions (2000 nM), cells cultured with 0, 20, or 200 nM folate exhibited delayed growth and increased apoptosis in an inverse dose-dependent manner. FD (0, 20, or 200 nM) significantly induced CIN (p < 0.001, p < 0.001, and p < 0.05, respectively). Moreover, FD significantly and inverse dose dependently increased the mRNA and protein expression of several key SAC-related genes. The results indicate that FD impairs SAC activity, which contributes to mitotic aberrations and CIN. These findings establish a novel association between FD and SAC dysfunction. Thus, FD-impaired spermatogenesis may be partly due to genomic instability and proliferation inhibition of spermatogonia.
Asunto(s)
Deficiencia de Ácido Fólico , Puntos de Control de la Fase M del Ciclo Celular , Masculino , Animales , Ratones , Espermatogonias/metabolismo , Semen/metabolismo , Deficiencia de Ácido Fólico/genética , Deficiencia de Ácido Fólico/metabolismo , Inestabilidad Cromosómica , Ácido Fólico/farmacología , Ácido Fólico/metabolismo , Espermatogénesis/genética , DietaRESUMEN
Sustainable TGF-ß1 signaling drives organ fibrogenesis. However, the cellular adaptation to maintain TGF-ß1 signaling remains unclear. In this study, we revealed that dietary folate restriction promoted the resolution of liver fibrosis in mice with nonalcoholic steatohepatitis. In activated hepatic stellate cells, folate shifted toward mitochondrial metabolism to sustain TGF-ß1 signaling. Mechanistically, nontargeted metabolomics screening identified that α-linolenic acid (ALA) is exhausted by mitochondrial folate metabolism in activated hepatic stellate cells. Knocking down serine hydroxymethyltransferase 2 increases the bioconversion of ALA to docosahexaenoic acid, which inhibits TGF-ß1 signaling. Finally, blocking mitochondrial folate metabolism promoted liver fibrosis resolution in nonalcoholic steatohepatitis mice. In conclusion, mitochondrial folate metabolism/ALA exhaustion/TGF-ßR1 reproduction is a feedforward signaling to sustain profibrotic TGF-ß1 signaling, and targeting mitochondrial folate metabolism is a promising strategy to enforce liver fibrosis resolution.
Asunto(s)
Ácido Fólico , Cirrosis Hepática , Mitocondrias , Ácido alfa-Linolénico , Animales , Ratones , Ácido alfa-Linolénico/deficiencia , Ácido alfa-Linolénico/metabolismo , Células Estrelladas Hepáticas/metabolismo , Hígado/citología , Hígado/metabolismo , Hígado/patología , Cirrosis Hepática/complicaciones , Cirrosis Hepática/metabolismo , Cirrosis Hepática/patología , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Ácido Fólico/metabolismo , Mitocondrias/metabolismo , Deficiencia de Ácido Fólico/complicaciones , Deficiencia de Ácido Fólico/metabolismo , Transducción de Señal , Retroalimentación FisiológicaRESUMEN
AIM: To demonstrate the role of IL-6 and pSTAT3 in the inflammatory response to cerebral ischemia/reperfusion following folic acid deficiency (FD). METHODS: The middle cerebral artery occlusion/reperfusion (MCAO/R) model was established in adult male Sprague-Dawley rats in vivo, and cultured primary astrocytes were exposed to oxygen-glucose deprivation/reoxygenation (OGD/R) to emulate ischemia/reperfusion injury in vitro. RESULTS: Glial fibrillary acidic protein (GFAP) expression significantly increased in astrocytes of the brain cortex in the MCAO group compared to the SHAM group. Nevertheless, FD did not further promote GFAP expression in astrocytes of rat brain tissue after MCAO. This result was further confirmed in the OGD/R cellular model. In addition, FD did not promote the expressions of TNF-α and IL-1ß but raised IL-6 (Peak at 12 h after MCAO) and pSTAT3 (Peak at 24 h after MCAO) levels in the affected cortices of MCAO rats. In the in vitro model, the levels of IL-6 and pSTAT3 in astrocytes were significantly reduced by treatment with Filgotinib (JAK-1 inhibitor) but not AG490 (JAK-2 inhibitor). Moreover, the suppression of IL-6 expression reduced FD-induced increases in pSTAT3 and pJAK-1. In turn, inhibited pSTAT3 expression also depressed the FD-mediated increase in IL-6 expression. CONCLUSIONS: FD led to the overproduction of IL-6 and subsequently increased pSTAT3 levels via JAK-1 but not JAK-2, which further promoted increased IL-6 expression, thereby exacerbating the inflammatory response of primary astrocytes.
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Isquemia Encefálica , Deficiencia de Ácido Fólico , Daño por Reperfusión , Animales , Masculino , Ratas , Astrocitos/metabolismo , Isquemia Encefálica/metabolismo , Deficiencia de Ácido Fólico/metabolismo , Infarto de la Arteria Cerebral Media/metabolismo , Interleucina-6/metabolismo , Ratas Sprague-Dawley , Reperfusión , Daño por Reperfusión/metabolismoRESUMEN
Neural tube defects (NTDs) are complex congenital malformations resulting from failure of neural tube closure during embryogenesis, which is affected by the interaction of genetic and environmental factors. It is well known that folate deficiency increases the incidence of NTDs; however, the underlying mechanism remains unclear. Folate deficiency not only causes DNA hypomethylation, but also blocks the synthesis of 2'-deoxythymidine-5'-monophosphate (dTMP) and increases uracil misincorporation, resulting in genomic instabilities such as base mismatch, DNA breakage, and even chromosome aberration. DNA repair pathways are essential for ensuring normal DNA synthesis, genomic stability and integrity during embryonic neural development. Genomic instability or lack of DNA repair has been implicated in risk of development of NTDs. Here, we reviewed the relationship between folate deficiency, DNA repair pathways and NTDs so as to reveal the role and significance of DNA repair system in the pathogenesis of NTDs and better understand the pathogenesis of NTDs.
Asunto(s)
Deficiencia de Ácido Fólico , Defectos del Tubo Neural , Humanos , Ácido Fólico/metabolismo , Defectos del Tubo Neural/genética , Deficiencia de Ácido Fólico/metabolismo , Reparación del ADN/genética , ADN , Inestabilidad GenómicaRESUMEN
BACKGROUND: DNA methylation (DNAme) erasure and reacquisition occur during prenatal male germ cell development; some further remodeling takes place after birth during spermatogenesis. Environmental insults during germline epigenetic reprogramming may affect DNAme, presenting a potential mechanism for transmission of environmental exposures across multiple generations. OBJECTIVES: We investigated how germ cell DNAme is impacted by lifetime exposures to diets containing either low or high, clinically relevant, levels of the methyl donor folic acid and whether resulting DNAme alterations were inherited in germ cells of male offspring of subsequent generations. MATERIALS AND METHODS: Female mice were placed on a control (FCD), 7-fold folic acid deficient (7FD) or 10- to 20-fold supplemented (10FS and 20FS) diet before and during pregnancy. Resulting F1 litters were weaned on the respective diets. F2 and F3 males received control diets. Genome-wide DNAme at cytosines (within CpG sites) was assessed in F1 spermatogonia, and in F1, F2 and F3 sperm. RESULTS: In F1 germ cells, a greater number of differentially methylated cytosines (DMCs) were observed in spermatogonia as compared with F1 sperm for all folic acid diets. DMCs were lower in number in F2 versus F1 sperm, while an unexpected increase was found in F3 sperm. DMCs were predominantly hypomethylated, with genes in neurodevelopmental pathways commonly affected in F1, F2 and F3 male germ cells. While no DMCs were found to be significantly inherited inter- or transgenerationally, we observed over-representation of repetitive elements, particularly young long interspersed nuclear elements (LINEs). DISCUSSION AND CONCLUSION: These results suggest that the prenatal window is the time most susceptible to folate-induced alterations in sperm DNAme in male germ cells. Altered methylation of specific sites in F1 germ cells was not present in later generations. However, the presence of DNAme perturbations in the sperm of males of the F2 and F3 generations suggests that epigenetic inheritance mechanisms other than DNAme may have been impacted by the folate diet exposure of F1 germ cells.
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Metilación de ADN , Deficiencia de Ácido Fólico , Embarazo , Masculino , Femenino , Ratones , Animales , Deficiencia de Ácido Fólico/genética , Deficiencia de Ácido Fólico/metabolismo , Semen/metabolismo , Epigénesis Genética , Espermatozoides/metabolismo , Ácido Fólico/metabolismo , Suplementos Dietéticos , Espermatogonias/metabolismo , ADN/metabolismoRESUMEN
Cerebral folate deficiency syndrome (CFDS) is defined as any neuropsychiatric or developmental disorder characterized by decreased CSF folate levels in the presence of normal folate status outside the nervous system. The specific clinical profile appears to be largely determined by the presence or absence of intrauterine folate deficiency as well as postnatal age at which cerebral folate deficiency occurs. The primary cause of CFDS is identified as the presence of serum folate receptor-alpha (FRα) autoantibodies impairing folate transport across the choroid plexus to the brain whereas, in a minority of cases, mitochondrial disorders, inborn errors of metabolism and loss of function mutations of the FRα (FOLR1) gene are identified. Early recognition and diagnosis of CFDS and prompt intervention is important to improve prognosis with successful outcomes. In this article we focus on FRα autoimmunity and its different age-dependent clinical syndromes, the diagnostic criteria, and treatments to be considered, including prevention strategies in this at-risk population.
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Deficiencia de Ácido Fólico , Ácido Fólico , Diagnóstico Precoz , Receptor 1 de Folato/deficiencia , Receptor 1 de Folato/genética , Receptor 1 de Folato/uso terapéutico , Ácido Fólico/uso terapéutico , Deficiencia de Ácido Fólico/metabolismo , Humanos , Distrofias Neuroaxonales , SíndromeRESUMEN
Early life stage folate status may influence neurodevelopment in offspring. The developmental origin of health and disease highlights the importance of the period of the first 1000 days (from conception to 2 years) of life. This study aimed to evaluate the effect of early life stage folic acid deficiency on de novo telomere synthesis, neurobehavioral development, and the cognitive function of offspring rats. The rats were divided into three diet treatment groups: folate-deficient, folate-normal, and folate-supplemented. They were fed the corresponding diet from 5 weeks of age to the end of the lactation period. After weaning, the offspring rats were still fed with the corresponding diet for up to 100 days. Neurobehavioral tests, folic acid and homocysteine (Hcy) levels, relative telomere length in brain tissue, and uracil incorporation in telomere in offspring were measured at different time points. The results showed that folic acid deficiency decreased the level of folic acid, increased the level of Hcy of brain tissue in offspring, increased the wrong incorporation of uracil into telomeres, and hindered de novo telomere synthesis. However, folic acid supplementation increased the level of folic acid, reduced the level of Hcy of brain tissue in offspring, reduced the wrong incorporation of uracil into telomeres, and protected de novo telomere synthesis of offspring, which was beneficial to the development of early sensory-motor function, spatial learning, and memory in adolescence and adulthood. In conclusion, early life stage folic acid deficiency had long-term inhibiting effects on neurodevelopment and cognitive function in offspring.
Asunto(s)
Deficiencia de Ácido Fólico , Animales , Cognición , Suplementos Dietéticos , Femenino , Ácido Fólico/metabolismo , Deficiencia de Ácido Fólico/complicaciones , Deficiencia de Ácido Fólico/metabolismo , Ratas , Telómero/metabolismo , UraciloRESUMEN
Proton coupled folate transporter (PCFT) is an integral membrane protein with 12 transmembrane segments localized to the plasma membrane. PCFT is the main route by which folate, vitamin B9, from dietary sources enters mammalian cells in the small intestine. Loss-of-function mutations in this membrane transport protein cause hereditary folate malabsorption, and upregulation of PCFT has been reported in cancer cells. Currently, a complete translocation mechanism of folate via PCFT is still missing. To reveal this mechanism via studies of structural architecture and structure-function relationships, soluble and stable PCFT in a phospholipid bilayer environment is needed. We therefore develop an approach to screen lipid environments in which PCFT is most soluble. Traditional in vitro expression and reconstitution into lipid bilayers of integral membrane proteins requires separate steps, which are costly and time-consuming. In this chapter, we describe a protocol for in vitro translation of PCFT into preformed lipid nanodiscs using a cell-free expression system, which helps to accelerate and reduce the cost of the sample preparation.
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Deficiencia de Ácido Fólico , Transportador de Folato Acoplado a Protón , Animales , Ácido Fólico/metabolismo , Deficiencia de Ácido Fólico/metabolismo , Lípidos , Mamíferos/metabolismo , Mutación , Transportador de Folato Acoplado a Protón/química , Transportador de Folato Acoplado a Protón/genética , Transportador de Folato Acoplado a Protón/metabolismoRESUMEN
Sperm DNA injury is one of the common causes of male infertility. Folic acid deficiency would increase the methylation level of the important genes, including those involved in DNA double-strand break (DSB) repair pathway. In the early stages, we analysed the correlation between seminal plasma folic acid concentration and semen parameters in 157 infertility patients and 91 sperm donor volunteers, and found that there was a significant negative correlation between seminal folic acid concentration and sperm DNA Fragmentation Index (DFI; r = -0.495, p < 0.01). Then through reduced representation bisulphite sequencing, global DNA methylation of sperm of patients in the low folic acid group and the high folic acid group was analysed, it was found that the methylation level in Rad54 promoter region increased in the folic acid deficiency group compared with the normal folic acid group. Meanwhile, the results of animal model and spermatocyte line (GC-2) also found that folic acid deficiency can increase the methylation level in Rad54 promoter region, increased sperm DFI in mice, increased the expression of γ-H2AX, that is, DNA injury marker protein, and increased sensitivity of GC-2 to external damage and stimulation. The study indicates that the expression of Rad54 is downregulated by folic acid deficiency via DNA methylation. This may be one of the mechanisms of sperm DNA damage caused by folate deficiency.
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Deficiencia de Ácido Fólico , Infertilidad Masculina , Animales , Daño del ADN , Fragmentación del ADN , Ácido Fólico/metabolismo , Deficiencia de Ácido Fólico/complicaciones , Deficiencia de Ácido Fólico/genética , Deficiencia de Ácido Fólico/metabolismo , Humanos , Infertilidad Masculina/genética , Infertilidad Masculina/metabolismo , Masculino , Ratones , Semen/química , Semen/metabolismo , Recuento de Espermatozoides , Espermatozoides/metabolismoRESUMEN
Hereditary spastic paraplegias are heterogeneous neurodegenerative disorders. Understanding of their pathogenic mechanisms remains sparse, and therapeutic options are lacking. We characterized a mouse model lacking the Cyp2u1 gene, loss of which is known to be involved in a complex form of these diseases in humans. We showed that this model partially recapitulated the clinical and biochemical phenotypes of patients. Using electron microscopy, lipidomic, and proteomic studies, we identified vitamin B2 as a substrate of the CYP2U1 enzyme, as well as coenzyme Q, neopterin, and IFN-α levels as putative biomarkers in mice and fluids obtained from the largest series of CYP2U1-mutated patients reported so far. We also confirmed brain calcifications as a potential biomarker in patients. Our results suggest that CYP2U1 deficiency disrupts mitochondrial function and impacts proper neurodevelopment, which could be prevented by folate supplementation in our mouse model, followed by a neurodegenerative process altering multiple neuronal and extraneuronal tissues.
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Familia 2 del Citocromo P450/genética , Familia 2 del Citocromo P450/metabolismo , Deficiencia de Ácido Fólico/genética , Deficiencia de Ácido Fólico/metabolismo , Ácido Fólico/farmacología , Animales , Biomarcadores/metabolismo , Encéfalo/metabolismo , Modelos Animales de Enfermedad , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Mitocondrias/genética , Mitocondrias/metabolismo , Mutación/genética , Fenotipo , Proteómica/métodosRESUMEN
Vitamin B12, folate, iron deficiency (IDA), chronic kidney disease (CKD), and anemia of inflammation (AI) are among the main causes of anemia in the elderly. WHO criteria of nutritional deficiencies neglect aging-related changes in absorption, metabolism, and utilization of nutrients. Age-specific criteria for the diagnosis of functional nutritional deficiency related to anemia are necessary. We examined the nationally representative sample of Polish seniors. Complete blood count, serum iron, ferritin, vitamin B12, folate, and renal parameters were assessed in 3452 (1632 women, 1820 men) participants aged above 64. Cut-off points for nutritional deficiencies were determined based on the WHO criteria (method-A), lower 2.5 percentile of the studied population (method-B), and receiver operating characteristic (ROC) analysis (method-C). Method-A leads to an overestimation of the prevalence of vitamin B12 and folate deficiency, while method-B to their underestimation with over 50% of unexplained anemia. Based on method-C, anemia was classified as nutritional in 55.9%. In 22.3% of cases, reasons for anemia remained unexplained, the other 21.8% were related to CKD or AI. Mild cases were less common in IDA, and more common in non-deficiency anemia. Serum folate had an insignificant impact on anemia. It is necessary to adopt the age-specific criteria for nutrient deficiency in an old population.
Asunto(s)
Anemia/etiología , Anemia/metabolismo , Anemia Ferropénica/complicaciones , Anemia Ferropénica/metabolismo , Femenino , Deficiencia de Ácido Fólico/complicaciones , Deficiencia de Ácido Fólico/metabolismo , Humanos , Inflamación/complicaciones , Inflamación/metabolismo , Masculino , Polonia , Deficiencia de Vitamina B 12/complicaciones , Deficiencia de Vitamina B 12/metabolismoRESUMEN
Folates have a pterine core structure and high metabolic activity due to their ability to accept electrons and react with O-, S-, N-, C-bounds. Folates play a role as cofactors in essential one-carbon pathways donating methyl-groups to choline phospholipids, creatine, epinephrine, DNA. Compounds similar to folates are ubiquitous and have been found in different animals, plants, and microorganisms. Folates enter the body from the diet and are also synthesized by intestinal bacteria with consequent adsorption from the colon. Three types of folate and antifolate cellular transporters have been found, differing in tissue localization, substrate affinity, type of transferring, and optimal pH for function. Laboratory criteria of folate deficiency are accepted by WHO. Severe folate deficiencies, manifesting in early life, are seen in hereditary folate malabsorption and cerebral folate deficiency. Acquired folate deficiency is quite common and is associated with poor diet and malabsorption, alcohol consumption, obesity, and kidney failure. Given the observational data that folates have a protective effect against neural tube defects, ischemic events, and cancer, food folic acid fortification was introduced in many countries. However, high physiological folate concentrations and folate overload may increase the risk of impaired brain development in embryogenesis and possess a growth advantage for precancerous altered cells.