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1.
Biochemistry (Mosc) ; 89(3): 562-573, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38648773

RESUMO

The contents of homocysteine (HCy), cyanocobalamin (vitamin B12), folic acid (vitamin B9), and pyridoxine (vitamin B6) were analyzed and the genotypes of the main gene polymorphisms associated with folate metabolism (C677T and A1298C of the MTHFR gene, A2756G of the MTR gene and A66G of the MTRR gene) were determined in children at the onset of multiple sclerosis (MS) (with disease duration of no more than six months), healthy children under 18 years (control group), healthy adults without neurological pathology, adult patients with MS at the onset of disease, and adult patients with long-term MS. A significant increase in the HCy levels was found in children at the MS onset compared to healthy children of the corresponding age. It was established that the content of HCy in children has a high predictive value. At the same time, an increase in the HCy levels was not accompanied by the deficiency of vitamins B6, B9, and B12 in the blood. The lack of correlation between the laboratory signs of vitamin deficiency and HCy levels may be due to the polymorphic variants of folate cycle genes. An increased HCy level should be considered as a marker of functional disorders of folate metabolism accompanying the development of pathological process in pediatric MS. Our finding can be used to develop new approaches to the prevention of demyelination in children and treatment of pediatric MS.


Assuntos
5-Metiltetra-Hidrofolato-Homocisteína S-Metiltransferase , Ácido Fólico , Homocisteína , Metilenotetra-Hidrofolato Redutase (NADPH2) , Esclerose Múltipla , Humanos , Homocisteína/sangue , Homocisteína/metabolismo , Esclerose Múltipla/sangue , Esclerose Múltipla/genética , Esclerose Múltipla/metabolismo , Ácido Fólico/sangue , Ácido Fólico/metabolismo , Feminino , Masculino , Criança , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/deficiência , Metilenotetra-Hidrofolato Redutase (NADPH2)/metabolismo , 5-Metiltetra-Hidrofolato-Homocisteína S-Metiltransferase/genética , 5-Metiltetra-Hidrofolato-Homocisteína S-Metiltransferase/metabolismo , Adulto , Adolescente , Deficiência de Vitaminas do Complexo B/complicações , Deficiência de Vitaminas do Complexo B/metabolismo , Deficiência de Vitaminas do Complexo B/sangue , Ferredoxina-NADP Redutase/genética , Ferredoxina-NADP Redutase/metabolismo , Vitamina B 12/sangue , Vitamina B 12/metabolismo , Idade de Início
2.
Curr Opin Biotechnol ; 87: 103132, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38669731

RESUMO

In the post-Green Revolution era, disparities in dietary access, rising obesity rates, demographic shifts, adoption of plant-based diets, and the impact of climate change collectively contribute to a progressive decline in dietary nutritional value, exacerbating B vitamin deficiencies across both low- and high-income countries. While the prevailing focus of biofortification has been on three micronutrients - provitamin A, iron, and zinc - utilizing conventional breeding, it is imperative to diversify biofortification strategies to combat micronutrient malnutrition. Metabolic engineering, facilitated by biotechnological tools, presents a promising avenue, contingent upon advances in fundamental knowledge, technological innovation, regulatory updates, and sustained public funding. Recognizing the intricate metabolic interplay of B vitamins in plants and humans, a comprehensive 'from metabolism to metabolism' approach is crucial for designing effective biofortification strategies that target multiple vitamins. This holistic perspective also extends beyond individual crops to encompass the entire food chain, a complex socioeconomic ecosystem that necessitates a paradigm shift, prioritizing quality over quantity.


Assuntos
Biofortificação , Biofortificação/métodos , Humanos , Complexo Vitamínico B/metabolismo , Engenharia Metabólica/métodos , Deficiência de Vitaminas do Complexo B/metabolismo
3.
J Inorg Biochem ; 223: 111546, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34304092

RESUMO

Recent studies have shown a correlation between COVID-19, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, and the distinct, exaggerated immune response titled "cytokine storm". This immune response leads to excessive production and accumulation of reactive oxygen species (ROS) that cause clinical signs characteristic of COVID-19 such as decreased oxygen saturation, alteration of hemoglobin properties, decreased nitric oxide (NO) bioavailability, vasoconstriction, elevated cytokines, cardiac and/or renal injury, enhanced D-dimer, leukocytosis, and an increased neutrophil to lymphocyte ratio. Particularly, neutrophil myeloperoxidase (MPO) is thought to be especially abundant and, as a result, contributes substantially to oxidative stress and the pathophysiology of COVID-19. Conversely, melatonin, a potent MPO inhibitor, has been noted for its anti-inflammatory, anti-oxidative, anti-apoptotic, and neuroprotective actions. Melatonin has been proposed as a safe therapeutic agent for COVID-19 recently, having been given with a US Food and Drug Administration emergency authorized cocktail, REGEN-COV2, for management of COVID-19 progression. This review distinctly highlights both how the destructive interactions of HOCl with tetrapyrrole rings may contribute to oxygen deficiency and hypoxia, vitamin B12 deficiency, NO deficiency, increased oxidative stress, and sleep disturbance, as well as how melatonin acts to prevent these events, thereby improving COVID-19 prognosis.


Assuntos
Antioxidantes/farmacologia , Tratamento Farmacológico da COVID-19 , Melatonina/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Anti-Inflamatórios/farmacologia , Apoptose/efeitos dos fármacos , COVID-19/imunologia , COVID-19/metabolismo , Síndrome da Liberação de Citocina/imunologia , Citocinas/metabolismo , Hemeproteínas/metabolismo , Humanos , Ácido Hipocloroso/metabolismo , Óxido Nítrico/metabolismo , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Peroxidase/metabolismo , SARS-CoV-2 , Sono/efeitos dos fármacos , Deficiência de Vitaminas do Complexo B/metabolismo
4.
Artigo em Inglês | MEDLINE | ID: mdl-33428888

RESUMO

Despite the well-established roles of B-vitamins and their deficiencies in health and disease, there is growing evidence indicating a key role of those nutrients in functions of the central nervous system and in psychopathology. Clinical data indicate the substantial role of B-vitamins in various psychiatric disorders, including major depression, bipolar disorder, schizophrenia, autism, and dementia, including Alzheimer's and Parkinson's diseases. As enzymatic cofactors, B-vitamins are involved in many physiological processes such as the metabolism of glucose, fatty acids and amino acids, metabolism of tryptophan in the kynurenine pathway, homocysteine metabolism, synthesis and metabolism of various neurotransmitters and neurohormones including serotonin, dopamine, adrenaline, acetylcholine, GABA, glutamate, D-serine, glycine, histamine and melatonin. Those vitamins are highly involved in brain energetic metabolism and respiration at the cellular level. They have a broad range of anti-inflammatory, immunomodulatory, antioxidant and neuroprotective properties. Furthermore, some of those vitamins are involved in the regulation of permeability of the intestinal and blood-brain barriers. Despite the fact that a substantial amount of the above vitamins is acquired from various dietary sources, deficiencies are not uncommon, and it is estimated that micronutrient deficiencies affect about two billion people worldwide. The majority of gut-resident microbes and the broad range of bacteria available in fermented food, express genetic machinery enabling the synthesis and metabolism of B-vitamins and, consequently, intestinal microbiota and fermented food rich in probiotic bacteria are essential sources of B-vitamins for humans. All in all, there is growing evidence that intestinal bacteria-derived vitamins play a significant role in physiology and that dysregulation of the "microbiota-vitamins frontier" is related to various disorders. In this review, we will discuss the role of vitamins in mental health and explore the perspectives and potential of how gut microbiota-derived vitamins could contribute to mental health and psychiatric treatment.


Assuntos
Eixo Encéfalo-Intestino/fisiologia , Encéfalo/metabolismo , Microbioma Gastrointestinal/fisiologia , Nível de Saúde , Transtornos Mentais/metabolismo , Complexo Vitamínico B/metabolismo , Humanos , Transtornos Mentais/dietoterapia , Transtornos Mentais/psicologia , Neurotransmissores/metabolismo , Probióticos/administração & dosagem , Probióticos/metabolismo , Deficiência de Vitaminas do Complexo B/dietoterapia , Deficiência de Vitaminas do Complexo B/metabolismo , Deficiência de Vitaminas do Complexo B/psicologia
5.
J Neurochem ; 157(3): 656-665, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-32797675

RESUMO

Dopamine (DA) has important roles in learning, memory, and motivational processes and is highly susceptible to oxidation. In addition to dementia, Alzheimer's disease (AD) patients frequently exhibit decreased motivation, anhedonia, and sleep disorders, suggesting deficits in dopaminergic neurotransmission. Vitamin C (ascorbate, ASC) is a critical antioxidant in the brain and is often depleted in AD patients as a result of disease-related oxidative stress and dietary deficiencies. To probe the effects of ASC deficiency and AD pathology on the DAergic system, gulo-/- mice, which like humans depend on dietary ASC to maintain adequate tissue levels, were crossed with APP/PSEN1 mice and provided sufficient or depleted ASC supplementation from weaning until 12 months of age. Ex vivo fast-scan cyclic voltammetry showed that chronic ASC depletion and APP/PSEN1 genotype both independently decreased dopamine release in the nucleus accumbens, a hub for motivational behavior and reward, while DA clearance was similar across all groups. In striatal tissue containing nucleus accumbens, low ASC treatment led to decreased levels of DA and its metabolites 3,4-dihydroxyohenyl-acetic acid (DOPAC), 3-methoxytyramine (3-MT), and homovanillic acid (HVA). Decreased enzyme activity observed through lower pTH/TH ratio was driven by a cumulative effect of ASC depletion and APP/PSEN1 genotype. Together the data show that deficits in dopaminergic neurotransmission resulting from age and disease status are magnified in conditions of low ASC which decrease DA availability during synaptic transmission. Such deficits may contribute to the non-cognitive behavioral changes observed in AD including decreased motivation, anhedonia, and sleep disorders.


Assuntos
Precursor de Proteína beta-Amiloide/genética , Presenilina-1/genética , Deficiência de Vitaminas do Complexo B/metabolismo , Envelhecimento/metabolismo , Animais , Ácido Ascórbico/farmacologia , Dopamina/metabolismo , Genótipo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Motivação/efeitos dos fármacos , Núcleo Accumbens/efeitos dos fármacos , Núcleo Accumbens/metabolismo , Tirosina 3-Mono-Oxigenase/metabolismo
6.
Nutrients ; 12(1)2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31963141

RESUMO

Vitamins and minerals are essential to humans as they play essential roles in a variety of basic metabolic pathways that support fundamental cellular functions. In particular, their involvement in energy-yielding metabolism, DNA synthesis, oxygen transport, and neuronal functions makes them critical for brain and muscular function. These, in turn, translate into effects on cognitive and psychological processes, including mental and physical fatigue. This review is focused on B vitamins (B1, B2, B3, B5, B6, B8, B9 and B12), vitamin C, iron, magnesium and zinc, which have recognized roles in these outcomes. It summarizes the biochemical bases and actions of these micronutrients at both the molecular and cellular levels and connects them with cognitive and psychological symptoms, as well as manifestations of fatigue that may occur when status or supplies of these micronutrients are not adequate.


Assuntos
Transtornos Cognitivos/tratamento farmacológico , Cognição/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Fadiga/tratamento farmacológico , Minerais/administração & dosagem , Vitaminas/administração & dosagem , Afeto/efeitos dos fármacos , Animais , Ácido Ascórbico/administração & dosagem , Deficiência de Ácido Ascórbico/metabolismo , Deficiência de Ácido Ascórbico/fisiopatologia , Deficiência de Ácido Ascórbico/prevenção & controle , Deficiência de Ácido Ascórbico/psicologia , Transtornos Cognitivos/metabolismo , Transtornos Cognitivos/fisiopatologia , Transtornos Cognitivos/psicologia , Fadiga/metabolismo , Fadiga/fisiopatologia , Fadiga/psicologia , Humanos , Ferro/administração & dosagem , Magnésio/administração & dosagem , Minerais/efeitos adversos , Estado Nutricional , Complexo Vitamínico B/administração & dosagem , Deficiência de Vitaminas do Complexo B/metabolismo , Deficiência de Vitaminas do Complexo B/fisiopatologia , Deficiência de Vitaminas do Complexo B/prevenção & controle , Deficiência de Vitaminas do Complexo B/psicologia , Vitaminas/metabolismo , Zinco/administração & dosagem
8.
Curr Osteoporos Rep ; 16(5): 554-560, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30116976

RESUMO

PURPOSE OF REVIEW: Homocystinuria is a congenital metabolic disorder in which cystathionine ß-synthase deficiency results in a prominent increase in homocysteine (serum levels > 100 µM), causing mental retardation, atherosclerotic cerebral infarction, and osteoporosis accompanied by fragility fractures. Encountering a case with excessive homocysteinemia such as that seen in hereditary homocystinuria is unlikely during usual medical examinations. However, in individuals who have vitamin B or folate deficiency, serum homocysteine concentrations are known to increase. These individuals may also have a polymorphism in methylenetetrahydrofolate reductase, MTHFR (C677T: TT type), which regulates homocysteine metabolism. These changes in homocysteine levels may elicit symptoms resembling those of homocystinuria (e.g., Alzheimer's disease, atherosclerosis, osteoporosis). RECENT FINDINGS: High serum homocysteine has been shown to have detrimental effects on neural cells, vascular endothelial cells, osteoblasts, and osteoclasts. Homocysteine is also known to increase oxidative stress, disrupt cross-linking of collagen molecules, and increase levels of advanced glycation end products, which results in reduced bone strength through a mechanism that goes beyond low bone density and increased bone resorption. Therefore, high serum homocysteine may be regarded as a factor that can reduce both bone mass and impair bone quality. In this review, we outline the epidemiology and pathophysiology of osteoporosis associated with hyperhomocysteinemia.


Assuntos
Osso e Ossos/metabolismo , Homocisteína/metabolismo , Hiper-Homocisteinemia/metabolismo , Osteoporose/metabolismo , Colágeno/metabolismo , Deficiência de Ácido Fólico/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Homocistinúria/complicações , Homocistinúria/genética , Homocistinúria/metabolismo , Humanos , Hiper-Homocisteinemia/complicações , Metilenotetra-Hidrofolato Redutase (NADPH2)/deficiência , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/metabolismo , Espasticidade Muscular/complicações , Espasticidade Muscular/genética , Espasticidade Muscular/metabolismo , Osteoblastos/metabolismo , Osteoclastos/metabolismo , Osteoporose/etiologia , Polimorfismo Genético , Transtornos Psicóticos/complicações , Transtornos Psicóticos/genética , Transtornos Psicóticos/metabolismo , Deficiência de Vitaminas do Complexo B/metabolismo
9.
Nutrients ; 8(12)2016 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-27973419

RESUMO

Alzheimer's disease (AD) is the major cause of dementia and no preventive or effective treatment has been established to date. The etiology of AD is poorly understood, but genetic and environmental factors seem to play a role in its onset and progression. In particular, factors affecting the one-carbon metabolism (OCM) are thought to be important and elevated homocysteine (Hcy) levels, indicating impaired OCM, have been associated with AD. We aimed at evaluating the role of polymorphisms of key OCM enzymes in the etiology of AD, particularly when intakes of relevant B-vitamins are inadequate. Our review indicates that a range of compensatory mechanisms exist to maintain a metabolic balance. However, these become overwhelmed if the activity of more than one enzyme is reduced due to genetic factors or insufficient folate, riboflavin, vitamin B6 and/or vitamin B12 levels. Consequences include increased Hcy levels and reduced capacity to synthetize, methylate and repair DNA, and/or modulated neurotransmission. This seems to favor the development of hallmarks of AD particularly when combined with increased oxidative stress e.g., in apolipoprotein E (ApoE) ε4 carriers. However, as these effects can be compensated at least partially by adequate intakes of B-vitamins, achieving optimal B-vitamin status for the general population should be a public health priority.


Assuntos
Doença de Alzheimer/etiologia , Medicina Baseada em Evidências , Hiper-Homocisteinemia/fisiopatologia , Metionina/metabolismo , Modelos Biológicos , Polimorfismo Genético , Deficiência de Vitaminas do Complexo B/fisiopatologia , 5-Metiltetra-Hidrofolato-Homocisteína S-Metiltransferase/genética , 5-Metiltetra-Hidrofolato-Homocisteína S-Metiltransferase/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/prevenção & controle , Animais , Cistationina beta-Sintase/genética , Cistationina beta-Sintase/metabolismo , Ferredoxina-NADP Redutase/genética , Ferredoxina-NADP Redutase/metabolismo , Predisposição Genética para Doença , Glicina Hidroximetiltransferase/genética , Glicina Hidroximetiltransferase/metabolismo , Humanos , Hiper-Homocisteinemia/genética , Hiper-Homocisteinemia/metabolismo , Hiper-Homocisteinemia/prevenção & controle , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/metabolismo , Mutagênese Insercional , Nutrigenômica/métodos , Nutrigenômica/tendências , Estado Nutricional , Polimorfismo de Nucleotídeo Único , Sequências de Repetição em Tandem , Complexo Vitamínico B/metabolismo , Complexo Vitamínico B/uso terapêutico , Deficiência de Vitaminas do Complexo B/dietoterapia , Deficiência de Vitaminas do Complexo B/metabolismo , Deficiência de Vitaminas do Complexo B/prevenção & controle
10.
Adv Clin Exp Med ; 25(3): 561-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27629746

RESUMO

The importance of vitamins in the prevention of cancer has attracted the attention of consumers, nutritionists and scientists for decades. The mechanisms of carcinogenesis, extended in the context of the function of vitamins, i.e. regulation of and participation in metabolic processes in the cell, suggest a substantial impact of these compounds on the initial stages of carcinogenesis. One-carbon metabolism involving folic acid, vitamins B2, B6 and B12, and folate metabolism doesn't only generate methyl groups, thus determining epigenetic processes, modifications of the genome and carcinogenesis. It also provides the compounds involved in the DNA synthesis and repair processes, especially the synthesis of purines and pyrimidines and the conversion of dUMP (2-deoxyuridine monophosphate) to dTMP (2-deoxythymidine monophosphate). In light of these pathways, folate, together with vitamins B2, B6 and B12, became a subject of interest as compounds whose deficit or surplus can potentially have an impact on the processes of carcinogenesis. Literature reports, however, do not fully confirm that the influence on the synthesis of nucleotides is connected with the inhibition of carcinogenesis. The impact of individual vitamins involved in one-carbon metabolism on carcinogenesis and their role in the prevention of these conditions depend on the type of cancer and the dose administered. Nevertheless, the research conducted makes it possible to conclude a considerable and probably long-underestimated role of these compounds in the prevention of serious, difficult to treat or incurable diseases.


Assuntos
Neoplasias/metabolismo , Neoplasias/prevenção & controle , Complexo Vitamínico B/metabolismo , Complexo Vitamínico B/uso terapêutico , Quimioprevenção/métodos , Ácido Fólico/metabolismo , Ácido Fólico/uso terapêutico , Humanos , Neoplasias/patologia , Medição de Risco , Fatores de Risco , Deficiência de Vitaminas do Complexo B/metabolismo
11.
Mol Cell Endocrinol ; 435: 48-60, 2016 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-27267668

RESUMO

One carbon metabolism or methyl transfer, a crucial component of metabolism in all cells and tissues, supports the critical function of synthesis of purines, thymidylate and methylation via multiple methyl transferases driven by the ubiquitous methyl donor s-adenosylmethionine. Serine is the primary methyl donor to the one carbon pool. Intracellular folates and methionine metabolism are the critical components of one carbon transfer. Methionine metabolism requires vitamin B12, B6 as cofactors and is modulated by endocrine signals and is responsive to nutrient intake. Perturbations in one carbon transfer can have profound effects on cell proliferation, growth and function. Epidemiological studies in humans and experimental model have established a strong relationship between impaired fetal growth and the immediate and long term consequences to the health of the offspring. It is speculated that during development, maternal environmental and nutrient influences by their effects on one carbon transfer can impact the health of the mother, impair growth and reprogram metabolism of the fetus, and cause long term morbidity in the offspring. The potential for such effects is underscored by the unique responses in methionine metabolism in the human mother during pregnancy, the absence of transsulfuration activity in the fetus, ontogeny of methionine metabolism in the placenta and the unique metabolism of serine and glycine in the fetus. Dietary protein restriction in animals and marginal protein intake in humans causes characteristic changes in one carbon metabolism. The impact of perturbations in one carbon metabolism on the health of the mother during pregnancy, on fetal growth and the neonate are discussed and their possible mechanism explored.


Assuntos
Carbono/metabolismo , Feto/metabolismo , Metilação , Gravidez/metabolismo , Animais , Feminino , Desenvolvimento Fetal , Retardo do Crescimento Fetal/metabolismo , Nível de Saúde , Humanos , Fenômenos Fisiológicos da Nutrição Pré-Natal , Deficiência de Proteína/complicações , Deficiência de Proteína/metabolismo , Deficiência de Vitaminas do Complexo B/complicações , Deficiência de Vitaminas do Complexo B/metabolismo
12.
Biochimie ; 126: 115-23, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27086080

RESUMO

Homocysteine (HCY) is a degradation product of the methionine pathway. The B vitamins, in particular vitamin B12 and folate, are the primary nutritional determinant of HCY levels and therefore their deficiencies result in hyperhomocysteinaemia (HHCY). Prevalence of hyperhomocysteinemia (HHCY) and related dietary deficiencies in B vitamins and folate increase with age and have been related to osteoporosis and abnormal development of epiphyseal cartilage and bone in rodents. Here we provide a review of experimental and population studies. The negative effects of HHCY and/or B vitamins and folate deficiencies on bone formation and remodeling are documented by cell models, including primary osteoblasts, osteoclast and bone progenitor cells as well as by animal and human studies. However, underlying pathophysiological mechanisms are complex and remain poorly understood. Whether these associations are the direct consequences of impaired one carbon metabolism is not clarified and more studies are still needed to translate these findings to human population. To date, the evidence is limited and somewhat conflicting, however further trials in groups most vulnerable to impaired one carbon metabolism are required.


Assuntos
Remodelação Óssea , Osso e Ossos/metabolismo , Carbono/metabolismo , Ácido Fólico/metabolismo , Homeostase , Osteoblastos/metabolismo , Osteoclastos/metabolismo , Vitamina B 12/metabolismo , Animais , Osso e Ossos/patologia , Homocisteína/metabolismo , Humanos , Hiper-Homocisteinemia/metabolismo , Hiper-Homocisteinemia/patologia , Osteoblastos/patologia , Deficiência de Vitaminas do Complexo B/metabolismo , Deficiência de Vitaminas do Complexo B/patologia
13.
Nutr Rev ; 74(5): 281-300, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27034475

RESUMO

B vitamin deficiency is a leading cause of neurological impairment and disability throughout the world. Multiple B vitamin deficiencies often coexist, and thus an understanding of the complex relationships between the different biochemical pathways regulated in the brain by these vitamins may facilitate prompter diagnosis and improved treatment. Particular populations at risk for multiple B vitamin deficiencies include the elderly, people with alcoholism, patients with heart failure, patients with recent obesity surgery, and vegetarians/vegans. Recently, new clinical settings that predispose individuals to B vitamin deficiency have been highlighted. Moreover, other data indicate a possible pathogenetic role of subclinical chronic B vitamin deficiency in neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis. In light of these findings, this review examines the clinical manifestations of B vitamin deficiency and the effect of B vitamin deficiency on the adult nervous system. The interrelationships of multiple B vitamin deficiencies are emphasized, along with the clinical phenotypes related to B vitamin deficiencies. Recent advances in the clinical determinants and diagnostic clues of B vitamin deficiency, as well as the suggested therapies for B vitamin disorders, are described.


Assuntos
Sistema Nervoso Central/patologia , Doenças do Sistema Nervoso/etiologia , Complexo Vitamínico B/metabolismo , Deficiência de Vitaminas do Complexo B/complicações , Adulto , Doença de Alzheimer/etiologia , Doença de Alzheimer/metabolismo , Esclerose Lateral Amiotrófica/etiologia , Esclerose Lateral Amiotrófica/metabolismo , Sistema Nervoso Central/metabolismo , Humanos , Doenças do Sistema Nervoso/metabolismo , Doença de Parkinson/etiologia , Doença de Parkinson/metabolismo , Deficiência de Vitaminas do Complexo B/metabolismo
14.
Nutrients ; 8(2): 68, 2016 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-26828517

RESUMO

The B-vitamins comprise a group of eight water soluble vitamins that perform essential, closely inter-related roles in cellular functioning, acting as co-enzymes in a vast array of catabolic and anabolic enzymatic reactions. Their collective effects are particularly prevalent to numerous aspects of brain function, including energy production, DNA/RNA synthesis/repair, genomic and non-genomic methylation, and the synthesis of numerous neurochemicals and signaling molecules. However, human epidemiological and controlled trial investigations, and the resultant scientific commentary, have focused almost exclusively on the small sub-set of vitamins (B9/B12/B6) that are the most prominent (but not the exclusive) B-vitamins involved in homocysteine metabolism. Scant regard has been paid to the other B vitamins. This review describes the closely inter-related functions of the eight B-vitamins and marshals evidence suggesting that adequate levels of all members of this group of micronutrients are essential for optimal physiological and neurological functioning. Furthermore, evidence from human research clearly shows both that a significant proportion of the populations of developed countries suffer from deficiencies or insufficiencies in one or more of this group of vitamins, and that, in the absence of an optimal diet, administration of the entire B-vitamin group, rather than a small sub-set, at doses greatly in excess of the current governmental recommendations, would be a rational approach for preserving brain health.


Assuntos
Encéfalo/metabolismo , Complexo Vitamínico B/metabolismo , Encéfalo/efeitos dos fármacos , Humanos , Complexo Vitamínico B/farmacologia , Complexo Vitamínico B/uso terapêutico , Deficiência de Vitaminas do Complexo B/tratamento farmacológico , Deficiência de Vitaminas do Complexo B/metabolismo
15.
J Nutr Sci Vitaminol (Tokyo) ; 61 Suppl: S145-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26598832

RESUMO

Pyridine nucleotide coenzymes (PNCs) are involved in over 500 enzyme reactions. PNCs are biosynthesized from the amino acid L-tryptophan (L-Trp), as well as the vitamin niacin. Hence, "true" niacin-deficient animals cannot be "created" using nutritional techniques. We wanted to establish a truly niacin-deficient model animal using a protocol that did not involve manipulating dietary L-Trp. We generated mice that are missing the quinolinic acid phosphoribosyltransferase (QPRT) gene. QPRT activity was not detected in qprt(-/-)mice. The qprt(+/+), qprt(+/-) or qprt(-/-) mice (8 wk old) were fed a complete diet containing 30 mg nicotinic acid (NiA) and 2.3 g L-Trp/kg diet or an NiA-free diet containing 2.3 g L-Trp/kg diet for 23 d. When qprt(-/-)mice were fed a complete diet, food intake and body weight gain did not differ from those of the qprt(+/+) and the qprt(+/-) mice. On the other hand, in the qprt(-/-) mice fed the NiA-free diet, food intake and body weight were reduced to 60% (p<0.01) and 70% (p<0.05) of the corresponding values for the qprt(-/-) mice fed the complete diet at day 23, respectively. The nutritional levels of niacin such as blood and liver NAD concentrations were also lower in the qprt(-/-) mice than in the qprt(+/+) and the qprt(+/-) mice. Urinary excretion of quinolinic acid was greater in the qprt(-/-) mice than in the qprt(+/+) and the qprt(+/-) mice (p<0.01). These data suggest that we generated truly niacin-deficient mice.


Assuntos
Modelos Animais de Doenças , Mutação , Niacina/deficiência , Estado Nutricional , Pentosiltransferases/metabolismo , Ácido Quinolínico/metabolismo , Deficiência de Vitaminas do Complexo B/metabolismo , Animais , Camundongos Endogâmicos C57BL , Camundongos Knockout , NAD/metabolismo , Niacina/metabolismo , Pentosiltransferases/genética , Deficiência de Vitaminas do Complexo B/enzimologia
16.
Cell Rep ; 13(1): 122-131, 2015 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-26411688

RESUMO

Bioenergetic metabolism varies during cell differentiation, but details of B cell metabolism remain unclear. Here, we show the metabolic changes during B cell differentiation in the intestine, where B cells differentiate into IgA(+) plasma cells (PCs). Naive B cells in the Peyer's patches (PPs) and IgA(+) PCs in the intestinal lamina propria (iLP) both used the tricarboxylic acid (TCA) cycle, but only IgA(+) PCs underwent glycolysis. These metabolic differences reflected their dependencies on vitamin B1, an essential cofactor for the TCA cycle. Indeed, the diminished activity of the TCA cycle after dietary vitamin B1 depletion decreased the number of naive B cells in PPs without affecting IgA(+) PCs in the iLP. The maintenance of naive B cells by dietary vitamin B1 was required to induce-but not maintain-intestinal IgA responses against oral antigens. These findings reveal the diet-mediated maintenance of B cell immunometabolism in organized and diffuse intestinal tissues.


Assuntos
Linfócitos B/metabolismo , Imunidade nas Mucosas , Mucosa Intestinal/metabolismo , Plasmócitos/metabolismo , Tiamina/metabolismo , Deficiência de Vitaminas do Complexo B/metabolismo , Animais , Anticorpos/metabolismo , Linfócitos B/citologia , Linfócitos B/imunologia , Diferenciação Celular , Linhagem da Célula/imunologia , Ciclo do Ácido Cítrico/imunologia , Feminino , Glicólise/imunologia , Imunidade Humoral , Imunoglobulina A/biossíntese , Imunoglobulina M/biossíntese , Mucosa Intestinal/citologia , Mucosa Intestinal/imunologia , Linfonodos/citologia , Linfonodos/imunologia , Linfonodos/metabolismo , Ativação Linfocitária , Depleção Linfocítica , Camundongos , Camundongos Endogâmicos BALB C , Nódulos Linfáticos Agregados/citologia , Nódulos Linfáticos Agregados/imunologia , Nódulos Linfáticos Agregados/metabolismo , Plasmócitos/citologia , Plasmócitos/imunologia , Tiamina/imunologia , Deficiência de Vitaminas do Complexo B/imunologia , Deficiência de Vitaminas do Complexo B/patologia
17.
Expert Rev Neurother ; 15(7): 793-802, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26092490

RESUMO

Cerebral folate deficiency is defined as any neurological condition associated with low cerebrospinal fluid folate concentrations. It is becoming increasingly associated with several neurological diseases, either genetic or environmental. Treatment of cerebral folate deficiency by folate supplementation is generally effective, improving the neurological outcome of some patients. However, to treat cerebral folate deficiency, the proper choice of one of the available folate forms is essential. The distinct brain folate metabolism features compared with peripheral folate metabolic pathways strongly suggest the investigation of different folate forms, such as the biologically active folinic acid and 5-methyltetrahydrofolate, since they are efficiently transported to the brain. Regarding the oral doses of the different folate forms, despite the fact that there are some recommendations, there is no general consensus. Further investigation and designing clinical trials are advisable to elucidate these aspects.


Assuntos
Doenças Cerebelares/etiologia , Doenças Cerebelares/terapia , Ácido Fólico/metabolismo , Deficiência de Vitaminas do Complexo B/complicações , Humanos , Deficiência de Vitaminas do Complexo B/metabolismo
18.
Biosci Biotechnol Biochem ; 79(1): 103-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25253514

RESUMO

The conversion of tryptophan (Trp) → nicotinamide (Nam) is an important pathway for supplying vitamin niacin. We reported the following two phenomena: (1) severe food restriction led to an increase in the Trp → Nam conversion compared with free-access control group; (2) the conversion of Trp → Nam is also increased by vitamin B1 deficiency compared with free-access control group. The present study was done to clarify whether or not a true reason about an increase in the Trp → Nam conversion is a vitamin B1 deficiency or severe food restriction. The present results showed that vitamin B1 deficiency suppressed the increased conversion of Trp → Nam induced by severe food restriction, probably by suppressing 3-hydroxyanthranilic acid 3,4-dioxygenase protein synthesis in liver.


Assuntos
Privação de Alimentos , Fígado/metabolismo , Niacinamida/metabolismo , Tiamina/metabolismo , Triptofano/metabolismo , Deficiência de Vitaminas do Complexo B/metabolismo , 3-Hidroxiantranilato 3,4-Dioxigenase/biossíntese , Ácido 3-Hidroxiantranílico/metabolismo , Animais , Fígado/patologia , Masculino , Niacina/metabolismo , Biossíntese de Proteínas , Ratos , Ratos Wistar , Deficiência de Vitaminas do Complexo B/patologia
19.
Artigo em Inglês | MEDLINE | ID: mdl-23887111

RESUMO

One-carbon metabolism, or methyl transfer, is critical for metabolism in all cells, is involved in the synthesis of purines, pyrimidines, in the methylation of numerous substrates, proteins, DNA and RNA, and in the expression of a number of genes. Serine is the primary endogenous methyl donor to the one carbon pool. Perturbations in methyl transfer due to nutrient and hormonal changes can have profound effect on cell function, growth and proliferation. It is postulated that at critical stages in development, nutrient and environmental influences by their effect on methyl transfer can impair fetal growth, reprogram metabolism and cause long-term morbidity in the offspring. The potential for their effects is underscored by the unique gestation-related changes in methyl transfer in healthy women, the late expression of transsulfuration cascade in the fetus and the unique metabolism of glycine and serine in the fetus. Dietary protein restriction in animal models and protein malnutrition in humans causes remarkable changes in the methyl transfer in vivo. Although the specific consequences of perturbation in maternal and fetal methyl transfer remain to be determined, a profound influence is suggested by the demonstrated relationship between maternal folate and B12 insufficiency and metabolic programming.


Assuntos
Carbono/metabolismo , Desenvolvimento Fetal/fisiologia , Retardo do Crescimento Fetal/metabolismo , Feto/metabolismo , Fenômenos Fisiológicos da Nutrição Pré-Natal , Deficiência de Proteína/complicações , Deficiência de Vitaminas do Complexo B/complicações , Aminoácidos/metabolismo , Animais , Metilação de DNA , Proteínas Alimentares/administração & dosagem , Feminino , Retardo do Crescimento Fetal/etiologia , Humanos , Metilação , Estado Nutricional , Gravidez , Deficiência de Proteína/metabolismo , Deficiência de Vitaminas do Complexo B/metabolismo
20.
Nutrition ; 29(5): 796-801, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23510569

RESUMO

OBJECTIVE: Pantothenic acid (PaA) is a vitamin that is an integral part of coenzyme A (CoA). CoA is an essential coenzyme in fat metabolism. The aim of this study was to determine whether PaA deficiency causes the accumulation of tissue fats and, if so, can refeeding of PaA decrease such accumulated fat. METHODS: Weaning rats were fed the PaA-free diet for 30 d. Rats were then divided into two groups. One group was continuously fed the PaA-free diet, and the other was fed the PaA-containing diet for an additional 13 d. At the end of the experiment, liver fat and perinephric fat were weighed, and plasma triglyceride levels measured. An additional similar experiment was conducted in which rats consumed 15% ethanol instead of water. RESULTS: Fat that accumulated by consuming the PaA-free diet for 30 d was decreased by consuming the PaA-containing diet for an additional 13 d. Ethanol feeding elicited much greater accumulation of liver, perinephric, and plasma fats if rats were fed the PaA-free diet. In such cases, administration of PaA could decrease the accumulated fat. CONCLUSION: PaA deficiency causes fat accumulation, and readministration of PaA decreases the tissue fat in rats fed the pantothenic acid-free diet. Ethanol accelerated the accumulation of fat in rats fed the PaA-free diet. PaA could be beneficial for decreasing accumulated tissue fat.


Assuntos
Etanol/efeitos adversos , Rim/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Lipídeos/sangue , Fígado/efeitos dos fármacos , Ácido Pantotênico/uso terapêutico , Deficiência de Vitaminas do Complexo B/tratamento farmacológico , Animais , Coenzima A/metabolismo , Dieta , Fígado Gorduroso/etiologia , Fígado Gorduroso/metabolismo , Rim/metabolismo , Fígado/metabolismo , Masculino , Ácido Pantotênico/deficiência , Ratos , Ratos Wistar , Complexo Vitamínico B/administração & dosagem , Complexo Vitamínico B/uso terapêutico , Deficiência de Vitaminas do Complexo B/complicações , Deficiência de Vitaminas do Complexo B/metabolismo , Desmame
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