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1.
Chembiochem ; 25(10): e202400184, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38573110

RESUMO

Genetic aberrations of the maternal UBE3A allele, which encodes the E3 ubiquitin ligase E6AP, are the cause of Angelman syndrome (AS), an imprinting disorder. In most cases, the maternal UBE3A allele is not expressed. Yet, approximately 10 percent of AS individuals harbor distinct point mutations in the maternal allele resulting in the expression of full-length E6AP variants that frequently display compromised ligase activity. In a high-throughput screen, we identified cyanocobalamin, a vitamin B12-derivative, and several alloxazine derivatives as activators of the AS-linked E6AP-F583S variant. Furthermore, we show by cross-linking coupled to mass spectrometry that cobalamins affect the structural dynamics of E6AP-F583S and apply limited proteolysis coupled to mass spectrometry to obtain information about the regions of E6AP that are involved in, or are affected by binding cobalamins and alloxazine derivatives. Our data suggest that dietary supplementation with vitamin B12 can be beneficial for AS individuals.


Assuntos
Síndrome de Angelman , Ubiquitina-Proteína Ligases , Vitamina B 12 , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/química , Ubiquitina-Proteína Ligases/genética , Síndrome de Angelman/genética , Síndrome de Angelman/tratamento farmacológico , Síndrome de Angelman/metabolismo , Humanos , Regulação Alostérica/efeitos dos fármacos , Vitamina B 12/metabolismo , Vitamina B 12/química , Vitamina B 12/farmacologia
2.
Nutrients ; 16(7)2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38613029

RESUMO

Methionine dependence is a characteristic of most cancer cells where they are unable to proliferate when the essential amino acid methionine is replaced with its precursor homocysteine in the growing media. Normal cells, on the other hand, thrive under these conditions and are referred to as methionine-independent. The reaction that adds a methyl group from 5-methyltetrahydrofolate to homocysteine to regenerate methionine is catalyzed by the enzyme methionine synthase with the cofactor cobalamin (vitamin B12). However, decades of research have shown that methionine dependence in cancer is not due to a defect in the activity of methionine synthase. Cobalamin metabolism has been tied to the dependent phenotype in rare cell lines. We have identified a human colorectal cancer cell line in which the cells regain the ability to proliferation in methionine-free, L-homocystine-supplemented media when cyanocobalamin is supplemented at a level of 1 µg/mL. In human SW48 cells, methionine replacement with L-homocystine does not induce any measurable increase in apoptosis or reactive oxygen species production in this cell line. Rather, proliferation is halted, then restored in the presence of cyanocobalamin. Our data show that supplementation with cyanocobalamin prevents the activation of the integrated stress response (ISR) in methionine-deprived media in this cell line. The ISR-associated cell cycle arrest, characteristic of methionine-dependence in cancer, is also prevented, leading to the continuation of proliferation in methionine-deprived SW48 cells with cobalamin. Our results highlight differences between cancer cell lines in the response to cobalamin supplementation in the context of methionine dependence.


Assuntos
Neoplasias Colorretais , Metionina , Humanos , Metionina/farmacologia , 5-Metiltetra-Hidrofolato-Homocisteína S-Metiltransferase , Vitamina B 12/farmacologia , Homocistina , Racemetionina , Linhagem Celular , Homocisteína , Neoplasias Colorretais/tratamento farmacológico
3.
BMJ Case Rep ; 17(4)2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38663893

RESUMO

Vitamin B12 is required for the formation of haematopoietic cells and the synthesis of myelin. Deficiency typically presents with fatigue and megaloblastic anaemia. Prolonged deficiency can cause neurological symptoms such as paresthesia, which can progress to subacute combined degeneration of the spinal cord. We describe an unusual presentation of B12 deficiency in a young man who was initially diagnosed and treated for cervical radiculopathy. This case highlights the challenges of diagnosing B12 deficiency in patients with neurologic but without haematologic, abnormalities. While the current incidence of B12 deficiency in developed countries is low, cases are likely to rise with the increased adoption of veganism. Clinicians should be aware of the variable presentations of B12 deficiency because delayed diagnosis and treatment increases morbidity and can cause irreversible neurological deficits.


Assuntos
Cervicalgia , Radiculopatia , Deficiência de Vitamina B 12 , Vitamina B 12 , Adulto , Humanos , Masculino , Vértebras Cervicais , Diagnóstico Diferencial , Cervicalgia/etiologia , Radiculopatia/etiologia , Radiculopatia/diagnóstico , Vitamina B 12/uso terapêutico , Deficiência de Vitamina B 12/complicações , Deficiência de Vitamina B 12/diagnóstico
4.
Am J Clin Nutr ; 119(3): 730-739, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38432714

RESUMO

BACKGROUND: Vitamin B-12 status in human milk (HM) has critical implications for infant growth and development. Few studies have separately evaluated the effects of prenatal and postnatal maternal high-dose vitamin B-12 supplementation on HM vitamin B-12 concentration. OBJECTIVES: This randomized controlled trial aimed to assess the effects of prenatal and postnatal vitamin B-12 supplementation on HM vitamin B-12 at 6 wk and 7 mo postpartum. METHODS: Pregnant women were enrolled in Dar es Salaam, Tanzania, between 2001 and 2004. From recruitment (12-27 weeks of gestation) through 6 wk postpartum, participants were randomly assigned to daily oral multiple micronutrient supplementation or placebo. From 6 wk to 18 mo postpartum, a subset of participants was randomly assigned to a postnatal supplement or placebo. The supplement included 50 µg/d of vitamin B-12 and various other vitamins. HM vitamin B-12 concentrations were analyzed at 6 wk and 7 mo postpartum for 412 participants. RESULTS: The prevalence of HM vitamin B-12 of <310 pmol/L was 73.3% and 68.4% at 6 wk and 7 mo postpartum, respectively. Prenatal supplementation increased HM vitamin B-12 concentration (percent difference: 34.4; 95% CI: 17.0, 54.5; P < 0.001) at 6 wk; this effect was not present at 7 mo. Postnatal supplementation increased HM vitamin B-12 concentration (percent difference: 15.9; 95% CI: 1.91, 31.9; P = 0.025) at 7 mo. Effect modification between prenatal and postnatal supplementation on HM vitamin B-12 status at 7 mo was found, with the effects of prenatal and postnatal supplements more pronounced among those receiving control during the other period; the prenatal supplement had a greater effect with postnatal control, and the postnatal supplement had a greater effect with prenatal control. CONCLUSIONS: Prenatal maternal vitamin B-12 supplementation has benefits on short-term HM status, and postnatal maternal vitamin B-12 supplementation has benefits on long-term HM status. This trial was registered at clinicaltrials.gov as NCT00197548. https://clinicaltrials.gov/ct2/show/NCT00197548.


Assuntos
Leite Humano , Vitamina B 12 , Gravidez , Lactente , Feminino , Humanos , Tanzânia , Vitaminas , Suplementos Nutricionais
5.
Am J Clin Nutr ; 119(3): 821-828, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38432716

RESUMO

BACKGROUND: The optimal dosage range for B-vitamin supplementation for stroke prevention has not received sufficient attention. OBJECTIVE: Our aim was to determine the optimal dosage range of a combination of folic acid, vitamin B12, and vitamin B6 supplementation in stroke prevention. METHODS: We searched PubMed, the Cochrane Central Register of Controlled Trials, and Embase database for randomized controlled trials published between January 1966 and April 2023, whose participants received B-vitamin supplementation and that reported the number of stroke cases. Relative risk (RR) was used to measure the effect of combined supplementation on risk of stroke using a fixed-effects model. Risk of bias was assessed with the Cochrane risk-of-bias algorithm. RESULTS: The search identified 14 randomized controlled trials of folic acid combined with vitamin B12 and vitamin B6 supplementation for stroke prevention that included 76,664 participants with 2720 stroke cases. In areas without and with partial folic acid fortification, combined B-vitamin supplementation significantly reduced the risk of stroke by 34% [RR: 0.66; 95% confidence interval (CI): 0.50, 0.86] and 11% (RR: 0.89; 95% CI: 0.79, 1.00), respectively. Further analysis showed that a dosage of folic acid ≤0.8 mg/d and vitamin B12 ≤0.4 mg/d was best for stroke prevention (RR: 0.65; 95% CI: 0.48, 0.86) in these areas. In contrast, no benefit of combined supplementation was found in fortified areas (RR: 1.04; 95% CI: 0.94, 1.16). CONCLUSIONS: Our meta-analysis found that the folic acid combined with vitamin B12 and vitamin B6 supplementation strategy significantly reduced the risk of stroke in areas without and with partial folic acid fortification. Combined dosages not exceeding 0.8 mg/d for folic acid and 0.4 mg/d for vitamin B12 supplementation may be more effective for populations within these areas. This trial was registered at PROSPERO asCRD42022355077.


Assuntos
Acidente Vascular Cerebral , Vitaminas , Humanos , Vitamina B 12/uso terapêutico , Ácido Fólico/uso terapêutico , Vitamina B 6/uso terapêutico , Acidente Vascular Cerebral/prevenção & controle , Suplementos Nutricionais
6.
Nutrients ; 16(5)2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38474861

RESUMO

BACKGROUND & AIMS: Low plasma B12 and folate levels or hyperhomocysteinemia are related to cognitive impairment. This study explores the relationships among diet pattern, blood folate-B12-homocysteine levels, and cognition measurement in Alzheimer's disease (AD) while exploring whether a gender effect may exist. METHODS: This cross-sectional study enrolled 592 AD patients (246 males, 346 females) and the demographic data, blood biochemical profiles, Mini-Mental State Examination (MMSE), and a Food Frequency Questionnaire (FFQ) for quantitative assessment of dietary frequency were collected. Structural Equation Modeling (SEM) was employed to explore the associations among dietary patterns, blood profiles, and cognition. A least absolute shrinkage and selection operator regression model, stratified by gender, was constructed to analyze the weighting of possible confounders. RESULTS: Higher MMSE scores were related to higher frequencies of coffee/tea and higher educational levels, body mass index, and younger age. The SEM model revealed a direct influence of dietary frequencies (skimmed milk, thin pork, coffee/tea) and blood profiles (homocysteine, B12, and folate) on cognitive outcomes. At the same time, the influence of dietary pattern on cognition was not mediated by folate-B12-homocysteine levels. In males, a direct influence on the MMSE is attributed to B12, while in females, homocysteine is considered a more critical factor. CONCLUSIONS: Dietary patterns and blood profiles are both associated with cognitive domains in AD, and there are gender differences in the associations of dietary patterns and the levels of B12 and homocysteine. To enhance the quality of dietary care and nutritional status for individuals with dementia, our study results still require future validations with multi-center and longitudinal studies.


Assuntos
Doença de Alzheimer , Ácido Fólico , Masculino , Feminino , Humanos , Doença de Alzheimer/psicologia , Estudos Transversais , Fatores Sexuais , Café , Vitamina B 12 , Dieta , Cognição , Chá , Homocisteína
7.
Clin Nutr ESPEN ; 60: 348-355, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38479934

RESUMO

BACKGROUND & AIMS: Patients receiving oncological esophagectomy or gastrectomy are known to be at high risk for vitamin and micronutrient deficiency before, during and after surgery. However, there are no clear guidelines for these cancer patients regarding postoperative vitamin supplementation. METHODS: We conducted a metanalysis consisting of 10 studies regarding vitamin and micronutrient deficiencies after oncological gastric or esophageal resection. 5 databases were searched. RESULTS: Data was sufficient regarding Vitamins B12 and 25-OH D3 as well as calcium. We were able to show deficiencies in 25-OH Vitamin D3 levels (p < 0.001) and lower levels of Vitamin B12 and calcium (bit p < 0.001) when compared to the healthy population. CONCLUSIONS: Patients from these groups are at risk for vitamin deficiencies. A guideline on postoperative supplementation is needed.


Assuntos
Deficiência de Vitaminas , Neoplasias Esofágicas , Desnutrição , Obesidade Mórbida , Neoplasias Gástricas , Humanos , Neoplasias Esofágicas/cirurgia , Neoplasias Gástricas/cirurgia , Cálcio , Obesidade Mórbida/cirurgia , Vitaminas , Desnutrição/complicações , Vitamina B 12
8.
BMC Pulm Med ; 24(1): 121, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38448889

RESUMO

BACKGROUND: Erlotinib is a first-generation, tyrosine kinase inhibitor of the epidermal growth factor receptor (EGFR-TKI) used for the treatment patients with NSCLC. Erlotinib is considered as a safe and effective treatment option, with generally good tolerance. Diarrhea and rash are the most common side effects, and more rare side effects appear in long-term real-world applications. Severe erlotinib related megaloblastic anemia is rare and remains unreported. This is the first case report of severe megaloblastic anemia in a patient with advanced lung adenocarcinoma with an EGFR L858R mutation treated with erlotinib. In this report, the clinical manifestations, diagnosis and treatment of erlotinib related severe megaloblastic anemia are described, and the possible pathogenesis and related treatment options are discussed. CASE DESCRIPTION: Herein, we present a 57- year-old non-smoking female diagnosed with metastatic lung adenocarcinoma harboring an EGFR L858R mutation, who had received erlotinib as the first-line therapy. After 44 weeks of treatment, the patient developed severe anemia. Anemia was manifested as megaloblastic anemia with elevated mean corpuscular volume and mean corpuscular hemoglobin. The total vitamin B12 level was below the detection limit of 50.00 pg /mL. Bone marrow smear suggested megaloblastic anemia. Her hematologic parameters were markedly recovered following the withdrawal of erlotinib and vitamin B12 supplement. As a result, the patient was diagnosed with erlotinib-associated megaloblastic anemia. CONCLUSIONS: This is the first case of severe megaloblastic anemia reported with erlotinib. Few of these hematologic adverse effects have been observed in studies on erlotinib, this case report highlights this possibility for long-term erlotinib administration. Close clinical and blood monitoring is recommended for patients receiving long-term TKI therapy.


Assuntos
Adenocarcinoma de Pulmão , Anemia Megaloblástica , Anemia , Neoplasias Pulmonares , Humanos , Feminino , Pessoa de Meia-Idade , Cloridrato de Erlotinib/efeitos adversos , Anemia Megaloblástica/induzido quimicamente , Adenocarcinoma de Pulmão/tratamento farmacológico , Receptores ErbB/genética , Neoplasias Pulmonares/tratamento farmacológico , Vitamina B 12
9.
Clin Nutr ; 43(4): 1025-1032, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38527394

RESUMO

BACKGROUND & AIMS: While vitamin B12 (B12) deficiency is considered as the hallmark of pernicious anemia (PA), iron deficiency (ID) is also prevalent. Indeed, this auto immune gastritis is responsible for parietal cell atrophy and increase in gastric pH, leading to impaired iron absorption. We compared PA patients' features according to their iron status at PA diagnosis, and we assessed the iron status recovery after oral or intravenous iron supplementation. METHODS: We prospectively included patients presenting with a newly diagnosed PA in a tertiary referral hospital between November 2018 and October 2020. Iron status was assessed at PA diagnosis then regularly during a standardized follow-up. In case of ID, the decision of treatment with oral and/or intravenous iron supplementation was left to the clinician convenience. RESULTS: We included 28 patients with newly diagnosed PA. ID was observed in 21/28 (75.0%) patients: from the PA diagnosis in 13 patients, or during the follow-up in 8 patients. Iron deficient PA patients had higher plasma B12 (p = 0.04) and lower homocysteine levels (p = 0.04). Also, ID was independently associated with the 'APCA (anti-parietal cell antibodies) alone' immunological status (absence of anti-intrinsic factor antibodies) after adjustment for age, gender and B12 level (aOR 12.1 [1.1-141.8], p = 0.04). High level of APCA was associated with lower ferritin level. After 3 months of supplementation, 3/11 PA patients normalized the iron status with oral iron supplementation, versus 7/8 with intravenous iron supplementation (p = 0.02). CONCLUSION: The high frequency of iron deficiency in PA highlights the interest of regular assessment of iron status in this condition. ID was associated with a profile including APCA alone and less pronounced B12 deficiency. Intravenous iron supplementation seemed to be more efficient than an oral supplementation in these preliminary data.


Assuntos
Anemia Perniciosa , Deficiências de Ferro , Deficiência de Vitamina B 12 , Humanos , Anemia Perniciosa/complicações , Anemia Perniciosa/tratamento farmacológico , Ferro , Deficiência de Vitamina B 12/complicações , Deficiência de Vitamina B 12/tratamento farmacológico , Dados Preliminares , Vitamina B 12/uso terapêutico , Autoanticorpos , Suplementos Nutricionais
10.
Gut Microbes ; 16(1): 2298697, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38303501

RESUMO

The early life gut microbiome affects the developing brain, and therefore may serve as a target to support neurodevelopment of children living in stressful and under-resourced environments, such as Black youth living on the South Side of Chicago, for whom we observe racial disparities in health. Microbiome compositions/functions key to multiple neurodevelopmental facets have not been studied in Black children, a vulnerable population due to racial disparities in health; thus, a subsample of Black infants living in urban, low-income neighborhoods whose mothers participated in a prenatal nutrition study were recruited for testing associations between composition and function of the gut microbiome (16S rRNA gene sequencing, shotgun metagenomics, and targeted metabolomics of fecal samples) and neurodevelopment (developmental testing, maternal report of temperament, and observed stress regulation). Two microbiome community types, defined by high Lachnospiraceae or Enterobacteriaceae abundance, were discovered in this cohort from 16S rRNA gene sequencing analysis; the Enterobacteriaceae-dominant community type was significantly negatively associated with cognition and language scores, specifically in male children. Vitamin B12 biosynthesis emerged as a key microbiome function from shotgun metagenomics sequencing analysis, showing positive associations with all measured developmental skills (i.e., cognition, language, motor, surgency, effortful control, and observed stress regulation). Blautia spp. also were identified as substantial contributors of important microbiome functions, including vitamin B12 biosynthesis and related vitamin B12-dependent microbiome functions, anti-inflammatory microbial surface antigens, competitive mechanisms against pathobionts, and production of antioxidants. The results are promising with respect to the potential for exploring therapeutic candidates, such as vitamin B12 nutritional or Blautia spp. probiotic supplementation, to support the neurodevelopment of infants at risk for experiencing racial disparities in health.


Assuntos
Microbioma Gastrointestinal , Vitamina B 12 , Lactente , Criança , Gravidez , Feminino , Adolescente , Humanos , Masculino , RNA Ribossômico 16S/genética , Microbioma Gastrointestinal/genética , Encéfalo , Vitaminas
11.
Trop Doct ; 54(3): 282-283, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38419508

RESUMO

Vitamin B12 and folate deficiency are reversible causes of megaloblastic anemia. Strict vegetarians are at risk of megaloblastic anemia due to low cobalamin in their diet. Knuckle hyperpigmentation in patients with megaloblastic anemia is due to excess melanin synthesis in skin. Here we present a case of a young vegetarian male with megaloblastic anemia with knuckle hyperpigmentation managed successfully with intravenous followed by oral vitamin b12 and folate supplementation.


Assuntos
Anemia Megaloblástica , Ácido Fólico , Hiperpigmentação , Deficiência de Vitamina B 12 , Vitamina B 12 , Humanos , Masculino , Deficiência de Vitamina B 12/diagnóstico , Deficiência de Vitamina B 12/tratamento farmacológico , Deficiência de Vitamina B 12/complicações , Hiperpigmentação/etiologia , Hiperpigmentação/diagnóstico , Vitamina B 12/uso terapêutico , Vitamina B 12/administração & dosagem , Anemia Megaloblástica/diagnóstico , Anemia Megaloblástica/tratamento farmacológico , Ácido Fólico/administração & dosagem , Ácido Fólico/uso terapêutico , Adulto , Suplementos Nutricionais , Dieta Vegetariana/efeitos adversos , Resultado do Tratamento
12.
Ir J Med Sci ; 193(4): 1827-1835, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38381379

RESUMO

Metformin is the most prescribed oral hypoglycemic drug and is considered by many health practitioners as the first-line treatment for non-insulin-dependent diabetes mellitus (T2DM). It is used either as a monotherapy or adjuvant to other anti-hyperglycemic agents. Most of its side effects are usually mild and self-limiting. However, several studies have shown an association between the use of metformin and low vitamin B12 levels in diabetic patients. The current review aimed to provide a literature review of the current published reports on the association, the possible mechanisms, and the related individualized risk factors that might lead to this incidence. The most accepted mechanism of the effect of metformin on vitamin B12 level is related to the absorption process where metformin antagonism of the calcium cation and interference with the calcium-dependent IF-vitamin B12 complex binding to the ileal cubilin receptor. In addition, many risk factors have been associated with the impact of metformin on vitamin B12 levels in diabetic patients such as dose and duration where longer durations showed a greater prevalence of developing vitamin B12 deficiency. Male patients showed lower levels of vitamin B12 compared to females. Black race showed a lower prevalence of vitamin B12 deficiency in metformin-treated patients. Moreover, chronic diseases including T2DM, hyperlipidemia, coronary artery disease, polycystic ovary disease (PCOD), obesity, and metformin therapy were significantly associated with increased risk of vitamin B12 deficiency.


Assuntos
Diabetes Mellitus Tipo 2 , Hipoglicemiantes , Metformina , Deficiência de Vitamina B 12 , Metformina/uso terapêutico , Metformina/efeitos adversos , Humanos , Deficiência de Vitamina B 12/induzido quimicamente , Deficiência de Vitamina B 12/epidemiologia , Hipoglicemiantes/uso terapêutico , Hipoglicemiantes/efeitos adversos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/complicações , Fatores de Risco , Masculino , Feminino , Vitamina B 12/uso terapêutico
13.
Appl Physiol Nutr Metab ; 49(6): 868-873, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38320263

RESUMO

There is concern that during a low-risk pregnancy, women are consuming more than recommended (400 µg/day) supplemental folic acid and may not meet recommendations for other nutrients. The objective of this study was to determine folic acid supplement use and dietary folate intakes in the second trimester (week 18) of pregnancy in women (n = 2996) in the Canadian CHILD cohort study. Vitamin B12 and choline intakes were also assessed because they are metabolically related to folate. The majority of participants (71.6%) were consuming a daily prenatal supplement. Twenty-eight percent of women (n = 847) reported consuming a folic acid supplement and of these women, 45.3% had daily supplemental folic acid intakes above the upper intake level (UL; 1000 µg/day). Daily dietary folate intakes were (mean (SD)) 575 (235) DFE µg/day. In contrast, only 24.8% of women met the dietary choline adequate intake (AI) recommendation (AI ≥ 450 mg/day) with a mean (SD) intake of 375 (151) mg/day. Further understanding of the impact of supplemental folic acid intake above the UL and low choline intake during pregnancy requires further investigation.


Assuntos
Colina , Suplementos Nutricionais , Ácido Fólico , Segundo Trimestre da Gravidez , Humanos , Feminino , Ácido Fólico/administração & dosagem , Colina/administração & dosagem , Gravidez , Canadá , Adulto , Estudos de Coortes , Recomendações Nutricionais , Vitamina B 12/administração & dosagem , Dieta , Fenômenos Fisiológicos da Nutrição Materna
14.
Nutrients ; 16(3)2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38337663

RESUMO

Cyanocobalamin (CNCbl) and aquo/hydroxocobalamin (HOCbl) are the forms of vitamin B12 that are most commonly used for supplementation. They are both converted to methylcobalamin (MeCbl) and 5'-deoxyadenosylcobalamin (AdoCbl), which metabolize homocysteine and methylmalonic acid, respectively. Here, we compare the kinetics of uptake and the intracellular transformations of radiolabeled CNCbl vs. HOCbl in HeLa cells. More HOCbl was accumulated over 4-48 h, but further extrapolation indicated similar uptake (>90%) for both vitamin forms. The initially synthesized coenzyme was MeCbl, which noticeably exceeded AdoCbl during 48 h. Yet, the synthesis of AdoCbl accelerated, and the predicted final levels of Cbls were MeCbl ≈ AdoCbl ≈ 40% and HOCbl ≈ 20%. The designed kinetic model revealed the same patterns of the uptake and turnover for CNCbl and HOCbl, apart from two steps. First, the "activating" intracellular processing of the internalized HOCbl was six-fold faster. Second, the detachment rates from the cell surface (when the "excessive" Cbl-molecules were refluxed into the external medium) related as 4:1 for CNCbl vs. HOCbl. This gave a two-fold faster cellular accumulation and processing of HOCbl vs. CNCbl. In medical terms, our data suggest (i) an earlier response to the treatment of Cbl-deficiency with HOCbl, and (ii) the manifestation of a successful treatment initially as a decrease in homocysteine.


Assuntos
Hidroxocobalamina , Vitamina B 12 , Humanos , Células HeLa , Vitamina B 12/metabolismo , Vitaminas , Homocisteína
15.
J Anim Sci ; 1022024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38407272

RESUMO

We hypothesized that restricted maternal nutrition and supplementation of one-carbon metabolites (OCM; methionine, folate, choline, and vitamin B12) would affect placental vascular development during early pregnancy. A total of 43 cows were bred, and 32 heifers successfully became pregnant with female calves, leading to the formation of four treatment groups: CON - OCM (n = 8), CON + OCM (n = 7), RES - OCM (n = 9), and RES + OCM (n = 8). The experimental design was a 2 × 2 factorial, with main factors of dietary intake affecting average daily gain: control (CON; 0.6 kg/d ADG) and restricted (RES; -0.23 kg/d ADG); and OCM supplementation (+OCM) in which the heifers were supplemented with rumen-protected methionine (7.4 g/d) and choline (44.4 g/d) and received weekly injections of 320 mg of folate and 20 mg of vitamin B12, or received no supplementation (-OCM; corn carrier and saline injections). Heifers were individually fed and randomly assigned to treatment at breeding (day 0). Placentomes were collected on day 63 of gestation (0.225 of gestation). Fluorescent staining with CD31 and CD34 combined with image analysis was used to determine the vascularity of the placenta. Images were analyzed for capillary area density (CAD) and capillary number density (CND). Areas evaluated included fetal placental cotyledon (COT), maternal placental caruncle (CAR), whole placentome (CAR + COT), intercotyledonary fetal membranes (ICOT, or chorioallantois), intercaruncular endometrium (ICAR), and endometrial glands (EG). Data were analyzed with the GLM procedure of SAS, with heifer as the experimental unit and significance at P ≤ 0.05 and a tendency at P > 0.05 and P < 0.10. Though no gain × OCM interactions existed (P ≥ 0.10), OCM supplementation increased (P = 0.01) CAD of EG, whereas nutrient restriction tended (P < 0.10) to increase CAD of ICOT and CND of COT. Additionally, there was a gain × OCM interaction (P < 0.05) for CAD within the placentome and ICAR, such that RES reduced and supplementation of RES with OCM restored CAD. These results indicate that maternal rate of gain and OCM supplementation affected placental vascularization (capillary area and number density), which could affect placental function and thus the efficiency of nutrient transfer to the fetus during early gestation.


In cow­calf production, periods of poor forage availability or quality can result in nutrient restriction during pregnancy. Previous studies have shown that even moderate maternal feed restriction during pregnancy, including very early in pregnancy, has profound effects on fetal and placental development, potentially having lasting impacts on calf growth and body composition later in life. One-carbon metabolites (OCM) in the diet are biomolecules required for methylation reactions and participate in the regulation of gene expression. Our objective was to evaluate the effects of nutrient restriction and OCM supplementation (specifically methionine, choline, folate, and vitamin B12) on placental vascular development during early pregnancy. Proper placental vascular development is necessary for healthy pregnancy outcomes, reflected by normal birth weight and healthy offspring. Our results indicated that maternal rate of gain and OCM supplementation affect placental vascularization, which could affect placental function and thereby fetal development throughout gestation. In the context of beef cattle production, our study sheds light on strategies that could enhance placental vascular development during early pregnancy. However, it is essential to recognize the nuances in our data, highlighting the need for further research to fully comprehend these intricate processes.


Assuntos
Complexo Ferro-Dextran , Placenta , Feminino , Gravidez , Animais , Bovinos , Melhoramento Vegetal , Metionina/farmacologia , Racemetionina , Carbono , Colina/farmacologia , Suplementos Nutricionais , Ácido Fólico/farmacologia , Vitamina B 12/farmacologia , Dieta/veterinária
16.
Br J Community Nurs ; 29(3): 137-146, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38421889

RESUMO

AIM: This study reviews research into the effects of the supplementation of B12 in the prevention and recovery of mental illness, and the potentiation of psychotropic medication. METHODOLOGY: This literature review follows a systematic approach to searching databases CINAHL, EMBASE, Medline, and PsycINFO where 287 non-duplicated articles results were received. Appropriate articles were identified through title and abstract screening and inclusion and exclusion criteria were applied. Five articles were chosen to address the research question following critical appraisal. Thematic analysis was then conducted. FINDINGS: This review identified five randomised controlled trials into the supplementation of various doses of B12 in conjunction with folic acid and B6. The supplement was measured against post-stroke depression prevention, the reduction of symptoms of depression in woman with cardiovascular disease, the effect on negative symptoms in schizophrenia, the reduction and prevention of depression in older adults, and the potentiation of psychotropic interventions. The papers reviewed showed inconclusive results, but evidence to support sub-groups and specific high-risk groups. Strong evidence showed supplementation of B12, folic acid and B6 has high rates of preventing post-stroke depression. CONCLUSION: The findings show that this area of research is still to be developed. The effects of B12 supplementation with other B vitamins on mental health have shown to be inconclusive. There is a case for its use to be considered within certain patient groups to aid recovery of mental health or in some high-risk patient groups. Recommendations are made for further research into high-risk groups of people that may have symptoms or symptoms that could be improved through the supplementation of B12.


Assuntos
Doenças Cardiovasculares , Vitamina B 12 , Feminino , Humanos , Idoso , Vitamina B 12/uso terapêutico , Ácido Fólico/uso terapêutico , Suplementos Nutricionais , Doenças Cardiovasculares/tratamento farmacológico , Avaliação de Resultados em Cuidados de Saúde
17.
PLoS One ; 19(2): e0290052, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38422016

RESUMO

Many commensal gut microbes are recognized for their potential to synthesize vitamin B12, offering a promising avenue to address deficiencies through probiotic supplementation. While bioinformatics tools aid in predicting B12 biosynthetic potential, empirical validation remains crucial to confirm production, identify cobalamin vitamers, and establish biosynthetic yields. This study investigates vitamin B12 production in three human colonic bacterial species: Anaerobutyricum hallii DSM 3353, Roseburia faecis DSM 16840, and Anaerostipes caccae DSM 14662, along with Propionibacterium freudenreichii DSM 4902 as a positive control. These strains were selected for their potential use as probiotics, based on speculated B12 production from prior bioinformatic analyses. Cultures were grown in M2GSC, chemically defined media (CDM), and Gorse extract medium (GEM). The composition of GEM was similar to CDM, except that the carbon and nitrogen sources were replaced with the protein-depleted liquid waste obtained after subjecting Gorse to a leaf protein extraction process. B12 yields were quantified using liquid chromatography with tandem mass spectrometry. The results suggested that the three butyrate-producing strains could indeed produce B12, although the yields were notably low and were detected only in the cell lysates. Furthermore, B12 production was higher in GEM compared to M2GSC medium. The positive control, P. freudenreichii DSM 4902 produced B12 at concentrations ranging from 7 ng mL-1 to 12 ng mL-1. Univariate-scaled Principal Component Analysis (PCA) of data from previous publications investigating B12 production in P. freudenreichii revealed that B12 yields diminished when the carbon source concentration was ≤30 g L-1. In conclusion, the protein-depleted wastes from the leaf protein extraction process from Gorse can be valorised as a viable substrate for culturing B12-producing colonic gut microbes. Furthermore, this is the first report attesting to the ability of A. hallii, R. faecis, and A. caccae to produce B12. However, these microbes seem unsuitable for industrial applications owing to low B12 yields.


Assuntos
Microbioma Gastrointestinal , Ulex , Humanos , Vitamina B 12 , Benzimidazóis , Carbono , Suplementos Nutricionais
18.
J Small Anim Pract ; 65(5): 317-328, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38354724

RESUMO

OBJECTIVES: Determine comparative tolerance of daily oral and weekly parenteral cobalamin supplementation, in hypocobalaminaemic dogs with chronic enteropathy. Determine whether oral is as effective as parenteral supplementation at achieving eucobalaminaemia, in hypocobalaminaemic dogs with protein-losing enteropathy, severe hypocobalaminaemia or high canine inflammatory bowel disease activity index at inclusion. MATERIALS AND METHODS: Thirty-seven client-owned dogs with hypocobalaminaemia and clinical signs of chronic enteropathy were prospectively enrolled in three UK referral centres. Dogs were randomly allocated to daily oral for 12 weeks or weekly parenteral cobalamin supplementation for 6 weeks and one additional dose 4 weeks later. Serum cobalamin, body condition score, canine inflammatory bowel disease activity index and bodyweight were assessed at inclusion, weeks 7 and 13. Serum methylmalonic acid concentration was evaluated at inclusion and at week 13. Owners completed treatment adherence, palatability, tolerance and satisfaction questionnaires at week 13. RESULTS: Nineteen dogs completed the study. All dogs orally supplemented achieved normal or increased cobalaminaemia at weeks 7 and 13. There was no statistical difference in cobalamin concentration at week 13 in dogs treated with oral or parenteral supplementation, regardless of presence of protein-losing enteropathy, severity of hypocobalaminaemia or canine inflammatory bowel disease activity index at inclusion. Serum methylmalonic acid concentration was not significantly different between oral and parenteral groups, neither were treatment adherence, satisfaction, and tolerance scores at week 13. CLINICAL SIGNIFICANCE: Oral is as effective and as well-tolerated as parenteral cobalamin supplementation in hypocobalaminaemic dogs with chronic enteropathy and severe clinical or biochemical phenotypes, and should be considered as a suitable treatment option regardless of disease severity.


Assuntos
Doenças do Cão , Deficiência de Vitamina B 12 , Vitamina B 12 , Animais , Cães , Feminino , Masculino , Administração Oral , Doença Crônica , Doenças do Cão/tratamento farmacológico , Doenças Inflamatórias Intestinais/veterinária , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/complicações , Estudos Prospectivos , Enteropatias Perdedoras de Proteínas/veterinária , Enteropatias Perdedoras de Proteínas/tratamento farmacológico , Resultado do Tratamento , Vitamina B 12/administração & dosagem , Vitamina B 12/uso terapêutico , Vitamina B 12/sangue , Deficiência de Vitamina B 12/veterinária , Deficiência de Vitamina B 12/tratamento farmacológico
19.
Am J Clin Nutr ; 119(3): 829-837, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38278366

RESUMO

BACKGROUND: Micronutrient deficiencies and anemia are widespread among children with stunting. OBJECTIVES: We assessed the effects of lipid-based nutrient supplements (LNS) containing milk protein (MP) and/or whey permeate (WP) on micronutrient status and hemoglobin (Hb) among children with stunting. METHODS: This was a secondary analysis of a randomized controlled trial. Children aged 12-59 mo with stunting were randomly assigned to LNS (100 g/d) with milk or soy protein and WP or maltodextrin for 12 wk, or no supplement. Hb, serum ferritin (S-FE), serum soluble transferrin receptor (S-TfR), plasma cobalamin (P-Cob), plasma methylmalonic acid (P-MMA), plasma folate (P-Fol), and serum retinol-binding protein (S-RBP) were measured at inclusion and at 12 wk. Data were analyzed using linear and logistic mixed-effects models. RESULTS: Among 750 children, with mean age ± SD of 32 ± 11.7 mo, 45% (n = 338) were female and 98% (n = 736) completed follow-up. LNS, compared with no supplementation, resulted in 43% [95% confidence interval (CI): 28, 60] greater increase in S-FE corrected for inflammation (S-FEci), 2.4 (95% CI: 1.2, 3.5) mg/L greater decline in S-TfR, 138 (95% CI: 111, 164) pmol/L greater increase in P-Cob, 33% (95% CI: 27, 39) reduction in P-MMA, and 8.5 (95% CI: 6.6, 10.3) nmol/L greater increase in P-Fol. There was no effect of LNS on S-RBP. Lactation modified the effect of LNS on markers of cobalamin status, reflecting improved status among nonbreastfed and no effects among breastfed children. LNS increased Hb by 3.8 (95% CI: 1.7, 6.0) g/L and reduced the odds of anemia by 55% (odds ratio: 0.45, 95% CI: 0.29, 0.70). MP compared with soy protein increased S-FEci by 14% (95% CI: 3, 26). CONCLUSIONS: LNS supplementation increases Hb and improves iron, cobalamin, and folate status, but not vitamin A status among children with stunting. LNS should be considered for children with stunting. This trial was registered at ISRCTN as 13093195.


Assuntos
Anemia , Oligoelementos , Criança , Humanos , Feminino , Lactente , Masculino , Micronutrientes/farmacologia , Proteínas de Soja , Uganda , Suplementos Nutricionais , Ácido Fólico/farmacologia , Anemia/tratamento farmacológico , Hemoglobinas/metabolismo , Transtornos do Crescimento , Lipídeos , Vitamina B 12
20.
BMC Nephrol ; 25(1): 13, 2024 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-38178022

RESUMO

BACKGROUND: Combined methylmalonic acidemia (MMA) and hyperhomocysteinemia, cobalamin C (cblC) type, also named cblC deficiency is a rare autosomal recessive genetic metabolic disease. It progressively causes neurological, hematologic, renal and other system dysfunction. The clinical manifestations are relatively different due to the onset time of disease. CASE PRESENTATION: This report describes a rare case of a 26 year old man with cblC deficiency who developed life-threatening aortic dissection and acute kidney injury (AKI) and showed neuropsychiatric symptoms with elevated serum homocysteine and methylmalonic aciduria. After emergent operation and intramuscular cobalamin supplementation therapy, the male recovered from aortic dissection, neurological disorder and AKI. Finally, two previously published compound heterozygous variants, c.482G > A (p.R161Q) and c.658_660del (p.K220del) in the MMACHC gene were detected in this patient and he was confirmed to have cblC deficiency. CONCLUSIONS: Poor cognizance of presenting symptoms and biochemical features of adult onset cblC disease may cause delayed diagnosis and management. This case is the first to depict a case of adult-onset cblC deficiency with aortic dissection. This clinical finding may contribute to the diagnosis of cblC deficiency.


Assuntos
Injúria Renal Aguda , Erros Inatos do Metabolismo dos Aminoácidos , Hiper-Homocisteinemia , Adulto , Masculino , Humanos , Hiper-Homocisteinemia/complicações , Hiper-Homocisteinemia/diagnóstico , Hiper-Homocisteinemia/genética , Vitamina B 12 , Erros Inatos do Metabolismo dos Aminoácidos/complicações , Erros Inatos do Metabolismo dos Aminoácidos/diagnóstico , Erros Inatos do Metabolismo dos Aminoácidos/genética , Injúria Renal Aguda/etiologia , Oxirredutases
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