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1.
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
2.
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
3.
Am J Clin Nutr ; 119(3): 821-828, 2024 Mar.
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
4.
J Coll Physicians Surg Pak ; 34(3): 351-354, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38462874

RESUMO

OBJECTIVE: To assess the impact of vitamin B12 levels in the failure of the dapoxetine used in premature ejaculation (PE) treatment. STUDY DESIGN: Experimental study. Place and Duration of the Study: Andrology Clinic, between May and December 2020. METHODOLOGY: Patients with premature ejaculation complaints completed the Premature Ejaculation Diagnostic Tool (PEDT) questionnaire. Patients were also asked to fill in the Premature Ejaculation Profile (PEP) surveys. Intravaginal ejaculation latency time (IELT) were recorded based on the estimates of patients. Serum vitamin B12 levels were evaluated based on blood samples. All patients were advised to use dapoxetine 30 mg, 1-3 hours prior to intercourse. After four weeks, patients were asked to complete the PEP questionnaire again. IELT times were recorded. RESULTS: A total of 62 patients were included in the study. A total of 39 patients (62.90%) were satisfied with the treatment of the dapoxetine. In comparison to patients who benefited from dapoxetine treatment and those who did not, vitamin B12 levels of patients who did not benefit from dapoxetine were found to be significantly lower (p=0.005). CONCLUSION: Vitamin B12 deficiency can reduce the effectiveness of dapoxetine treatment in patients with PE. It is important to evaluate serum vitamin B12 levels for the evaluation of patients with PE. KEY WORDS: Premature ejaculation, Dapoxetine, Vitamin B12, Serotonin, Treatment.


Assuntos
Benzilaminas , Naftalenos , Ejaculação Precoce , Masculino , Humanos , Ejaculação Precoce/tratamento farmacológico , Resultado do Tratamento , Ejaculação , Vitamina B 12/uso terapêutico
5.
J Pediatr Endocrinol Metab ; 37(4): 380-386, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38436354

RESUMO

OBJECTIVES: Transcobalamin II (TC) promotes the cellular uptake of cobalamin (Cbl) through receptor-mediated endocytosis of the TC-cbl complex in peripheral tissues. TC deficiency is a rare disorder that causes intracellular Cbl depletion. It presents in early infancy with a failure to thrive, diarrhea, anemia, agammaglobulinemia, and pancytopenia. Data from five TC-deficient patients including clinical, biochemical, and molecular findings, as well as long-term outcomes, were collected. CASE PRESENTATION: Mutation analysis revealed one unreported pathogenic variant in the TCN2 gene. One patient had exocrine pancreatic insufficiency. We conducted a retrospective analysis of C3 and C3/C2 from dried blood samples, as this is implemented for newborn screening (NBS). We detected a marked increase in the C3/C2 ratio in two samples. Treatment was based on parenteral Cbl. Three patients treated before six months of age had an initial favorable outcome, whereas the two treated later or inadequately had neurological impairment. CONCLUSIONS: This is the first report of Argentinean patients with TC deficiency that detected a new variant in TCN2. NBS may be a tool for the early detection of TC deficiency. This data emphasizes that TC deficiency is a severe disorder that requires early detection and long-term, aggressive therapy. Accurate diagnosis is imperative, because early detection and treatment can be life-saving.


Assuntos
Erros Inatos do Metabolismo dos Aminoácidos , Anemia Macrocítica , Deficiência de Vitamina B 12 , Recém-Nascido , Humanos , Vitamina B 12/uso terapêutico , Transcobalaminas/genética , Estudos Retrospectivos , Deficiência de Vitamina B 12/diagnóstico , Deficiência de Vitamina B 12/tratamento farmacológico , Deficiência de Vitamina B 12/genética , Erros Inatos do Metabolismo dos Aminoácidos/tratamento farmacológico , Diagnóstico Precoce
7.
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
8.
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
9.
Rheumatol Int ; 44(4): 737-741, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38294542

RESUMO

Vitamin B12 (cobalamin) deficiency is common in patients with rheumatic diseases. Pernicious anemia is a well-known cause, but recent reports suggest that autoimmune-derived deficiency may not be limited to this cause alone. Symptoms of low vitamin B12 concentration are often deceptive, mimicking and overlapping with symptoms of other conditions. Neuropsychiatric manifestations, anemia, and fatigue are frequently attributed to a rheumatic disease without further evaluation. In this study, we present three cases of patients with neuropathic pain, depression, fatigue, and muscle weakness, initially attributed to a rheumatic disease, which almost completely resolved after implementing vitamin B12 supplementation. Furthermore, we provide an overview of current scientific reports regarding the potential use of cobalamin in rheumatology. Treatment of pain and neuropathy, often very challenging in long-lasting rheumatic diseases, can be more effective after a course of vitamin B12, even when no apparent deficiency is detected in laboratory tests. Considering recent research demonstrating vitamin B12's nerve-protecting properties, we recommend that physicians should assess vitamin B12 levels early in the diagnostic process of rheumatic diseases. In specific cases, physicians should consider cobalamin supplementation regardless of vitamin B12 serum concentration.


Assuntos
Doenças Reumáticas , Reumatologia , Deficiência de Vitamina B 12 , Humanos , Deficiência de Vitamina B 12/complicações , Deficiência de Vitamina B 12/diagnóstico , Deficiência de Vitamina B 12/tratamento farmacológico , Vitamina B 12/uso terapêutico , Doenças Reumáticas/complicações , Doenças Reumáticas/diagnóstico , Doenças Reumáticas/tratamento farmacológico
10.
Mymensingh Med J ; 33(1): 303-306, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38163808

RESUMO

Pernicious anemia is an autoimmune disease leading to impaired absorption of dietary cobalamin. Patients with pernicious anemia can present with multiple hematological, neurological and gastrointestinal complaints. Herein, we have a case of pernicious anemia presenting with alternating bowel habit. This was challenging and unique as the patient didn't have any usual condition responsible for alternating bowel habit and it is not reported in cases of pernicious anemia either. The case is a 46-year-old male who was admitted with alternating bowel habit, paresthesia and fever for the last 6 months. Patient was found to be severely anemic. After full workup, he was diagnosed with pernicious anemia. The patient was treated with IM Injections of Vitamin B12. After 3 months of discharge, the patient was free of all the symptoms. This case emphasizes the importance of investigating anemic patients with alternating bowel habit for pernicious anemia and also the need to exclude other causes of this symptom before labeling it as pernicious anemia only.


Assuntos
Anemia Perniciosa , Doenças Autoimunes , Masculino , Humanos , Pessoa de Meia-Idade , Anemia Perniciosa/complicações , Anemia Perniciosa/diagnóstico , Vitamina B 12/uso terapêutico , Parestesia
11.
Artigo em Inglês | MEDLINE | ID: mdl-38231988

RESUMO

Subacute combined degeneration (SCD) of the spinal cord is a disease involving the lateral and posterior columns of the spinal cord that can manifest in patients with vitamin B12 deficiency. Nitrous oxide (N2O)-induced SCD of the spinal cord is a result of N2O interfering with the metabolism of vitamin B12 and results in nervous system demyelination. This is an infrequent complication of N2O anesthesia; however, cases are rising with recreational N2O use. This case report describes a patient with SCD of the spinal cord induced by recreational N2O abuse. The patient presented to a spine surgery clinic with a 3-week history of progressive global weakness and paresthesias. After a detailed history and physical examination, the diagnosis was made and supported by various tests and imaging findings. Despite marked neurologic deficits, the patient's symptoms improved markedly with therapy and vitamin B12 supplementation. Spine surgery clinicians may be confronted with these cases and should be aware of this atypical presentation of SCD. As in our case, patients may present with neurologic deficits of unclear etiology. Neurologic dysfunction may be irreversible; therefore, accurate diagnosis, medical treatment, and complete neurologic evaluation are of the utmost importance to prevent additional progression.


Assuntos
Degeneração Combinada Subaguda , Transtornos Relacionados ao Uso de Substâncias , Deficiência de Vitamina B 12 , Humanos , Degeneração Combinada Subaguda/induzido quimicamente , Degeneração Combinada Subaguda/complicações , Óxido Nitroso/efeitos adversos , Deficiência de Vitamina B 12/induzido quimicamente , Deficiência de Vitamina B 12/tratamento farmacológico , Deficiência de Vitamina B 12/complicações , Vitamina B 12/uso terapêutico , Vitamina B 12/farmacologia , Transtornos Relacionados ao Uso de Substâncias/complicações
12.
R I Med J (2013) ; 107(2): 13-15, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38285744

RESUMO

Subacute combined degeneration (SCD) is an acquired neurologic complication from prolonged vitamin B12 deficiency. As a result of dorsal and lateral spinal cord column degeneration, patients present with a range of neurological symptoms, including paresthesias, ataxia, and muscle weakness. Without prompt treatment, irreversible nerve damage occurs. Here we present a young man who developed progressive ascending paresthesias and lower extremity weakness after escalated nitrous oxide use. This case highlights the importance of considering SCD from nitrous oxide toxicity when patients present with progressive ataxia, paresthesia, and lower extremity weakness.


Assuntos
Doenças da Medula Espinal , Degeneração Combinada Subaguda , Deficiência de Vitamina B 12 , Masculino , Humanos , Óxido Nitroso/efeitos adversos , Parestesia/induzido quimicamente , Parestesia/complicações , Vitamina B 12/uso terapêutico , Deficiência de Vitamina B 12/induzido quimicamente , Deficiência de Vitamina B 12/complicações , Deficiência de Vitamina B 12/diagnóstico , Degeneração Combinada Subaguda/complicações , Doenças da Medula Espinal/complicações , Ataxia/complicações
15.
J Immunother ; 47(4): 117-122, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37909180

RESUMO

Metabolic pathways may regulate responses to cancer immunotherapy (IO). Due to its immunomodulatory properties, we sought to examine the association between serum vitamin B12 (VitB12) and survival in individuals with cancer treated with immune checkpoint inhibitors, compared with biological and chemotherapy. We collected data on patients with advanced cancer initiating intravenous antineoplastic treatment and a concomitant VitB12 measurement (elevated: >820 ng/L), between January 2010 and January 2022. Patients on IO and other regimens (control) were compared using the Mann-Whitney test for continuous variables, χ 2 test or Fisher test for categorical variables, and multivariate Cox regression models assessed the effect of VitB12 on overall survival and progression-free survival, adjusting for confounders. Patient groups (control: n = 408; IO: n = 93) were balanced for the treatment line and VitB12 (elevated 29.9% vs 23.7%; mean 762.4 vs 687.6 ng/L). In multivariate analysis, overall survival in all patients was negatively associated with VitB12 [control: hazard ratio (HR): 1.4, 95% CI: 1.01-1.96, P = 0.04, false discovery rate (FDR): 0.069; IO: HR: 2.74 as sum of linear baseline and interaction effects, log scale], age (HR: 1.03, 95% CI: 1.02-1.04, P < 0.01), male sex (HR: 0.66, 95% CI: 0.50-0.88, P < 0.01), and neutrophil-to-lymphocyte ratio (HR: 1.05, 95% CI: 0.48-0.99, P = 0.01). However, VitB12 was significantly negatively associated with progression-free survival only in the IO group ( P < 0.001, FDR < 0.001, calculated HR: 8.34; biological treatment P = 0.08; FDR: 0.111; neutrophil-to-lymphocyte ratio, P = 0.07; FDR: 0.09). Taken together, elevated VitB12 was a negative predictor for outcomes on IO, independently of other known prognostic factors. Further research is needed to elucidate the immune-metabolic interplay and its interaction with the gut microbiome, as well as interventional strategies to enhance IO responses.


Assuntos
Antineoplásicos , Neoplasias , Humanos , Masculino , Neoplasias/tratamento farmacológico , Antineoplásicos/uso terapêutico , Intervalo Livre de Progressão , Imunoterapia , Vitamina B 12/uso terapêutico , Estudos Retrospectivos
16.
Chem Biol Interact ; 387: 110823, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38049026

RESUMO

Chronic hyperglycemia-induced neuropathological changes include neuronal apoptosis, astrogliosis, decrease in neurotrophic support, impaired synaptic plasticity, and impaired protein quality control (PQC) system. Vitamin B12 is indispensable for neuronal development and brain function. Several studies reported the neuroprotective effect of B12 supplementation in diabetic patients. However, the underlying molecular basis for the neuroprotective effect of B12 supplementation in diabetes needs to be thoroughly investigated. Two-month-old Sprague-Dawley rats were randomly assigned into three groups: Control (CN), diabetes (D; induced with streptozotocin; STZ), and diabetic rats supplemented with vitamin B12 (DBS; vitamin B12; 50 µg/kg) for four months. At the end of 4 months of experimentation, the brain was dissected to collect the cerebral cortex (CC). The morphology of CC was investigated with H&E and Nissl body staining. Neuronal apoptosis was determined with TUNEL assay. The components of neurotrophic support, astrogliosis, synaptic plasticity, and PQC processes were investigated by immunoblotting and immunostaining methods. H& E, Nissl body, and TUNEL staining revealed that diabetes-induced neuronal apoptosis and degeneration. However, B12 supplementation ameliorated the diabetes-induced neuronal apoptosis. Further, B12 supplementation restored the markers of neurotrophic support (BDNF, NGF, and GDNF), and synaptic plasticity (SYP, and PSD-95) in diabetic rats. Interestingly, B12 supplementation also attenuated astrogliosis, ER stress, and ameliorated autophagy-related proteins in diabetic rats. Overall, these findings suggest that B12 acts as a neuroprotective agent by inhibiting the neuropathological changes in STZ-induced type 1 diabetes. Thus, B12 supplementation could produce beneficial outcomes including neuroprotective effects in diabetic patients.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 1 , Fármacos Neuroprotetores , Ratos , Humanos , Animais , Lactente , Vitamina B 12/farmacologia , Vitamina B 12/uso terapêutico , Ratos Sprague-Dawley , Estreptozocina/farmacologia , Diabetes Mellitus Experimental/metabolismo , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Diabetes Mellitus Tipo 1/induzido quimicamente , Diabetes Mellitus Tipo 1/tratamento farmacológico , Gliose , Apoptose
17.
Nutr Clin Pract ; 39(2): 356-365, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38030578

RESUMO

High-dose vitamin B12 is a potential treatment for patients with vasodilatory shock that is refractory to other therapies. Vasodilatory shock is characterized by low blood pressure and low systemic vascular resistance. Nitric oxide and hydrogen sulfide, two potential targets of high-dose vitamin B12 given as hydroxocobalamin, facilitate this syndrome. This review explores the relationship between high-dose vitamin B12 and hemodynamic outcomes in adults with vasodilatory shock and provides an update on the literature since a 2019 review on this topic. A literature search of studies published in the past 5 years was conducted in the CINAHL, PubMed, Cochrane, and EMBASE databases in May 2023. After assessing for eligibility, eight studies met this review's inclusion criteria. Seven of the eight studies reported decreased vasopressor requirements for part or all of the study samples after receiving a hydroxocobalamin infusion. However, not all patients responded to hydroxocobalamin. These findings are limited by patient selection and differences in the timing of vasopressor requirement and blood pressure outcome assessments. The current evidence is promising as to whether vitamin B12 , given as a hydroxocobalamin infusion, may improve hemodynamic outcomes in vasodilatory shock, but the evidence is of low quality. The use of hydroxocobalamin to treat refractory, vasodilatory shock remains investigative. Larger randomized controlled trials are required to elucidate the role of vitamin B12 in treating refractory, vasodilatory shock, including in conjunction with other alternative therapies such as methylene blue and corticosteroids.


Assuntos
Choque , Vitamina B 12 , Adulto , Humanos , Vitamina B 12/uso terapêutico , Hidroxocobalamina/uso terapêutico , Choque/tratamento farmacológico , Vasoconstritores/uso terapêutico , Vitaminas/uso terapêutico
18.
Mol Pharm ; 21(1): 137-142, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37989273

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) remains one of the most dismal diagnoses that a patient can receive. PDAC is extremely difficult to treat, as drug delivery is challenging in part due to the lack of vascularization, high stromal content, and high collagen content of these tumors. We have previously demonstrated that attaching drugs to the cobalamin scaffold provides selectivity for tumors over benign cells due to a high vitamin demand in these rapidly growing cells and an overexpression of transcobalamin receptors in a variety of cancer types. Importantly, we have shown the ability to deliver cobalamin derivatives to orthotopic pancreas tumors. Tyrosine kinase inhibitors have shown promise in treating PDAC as well as other cancer types. However, some of these inhibitors suffer from drug resistance, and as such, their success has been diminished. With this in mind, we synthesized the tyrosine kinase inhibitors erlotinib (EGFR) and dasatinib (Src) that are attached to this cobalamin platform. Both of these cobalamin-drug conjugates cause visible light-induced apoptosis, and the cobalamin-erlotinib conjugate (2) causes X-ray-induced apoptosis in MIA PaCa-2 cells. Both visible light and X-rays provide spatial control of drug release; however, utilizing X-ray irradiation offers the advantage of deeper tissue penetration. Therefore, we explored the utilization of 2 as a synergistic therapy with radiation in athymic nude mice implanted with MIA PaCa-2 tumors. We discovered that the addition of 2 caused an enhanced reduction in tumor margins in comparison with radiation therapy alone. In addition, treatment with 2 in the absence of radiation caused no significant reduction in tumor size in comparison with the controls. The cobalamin technology presented here allows for the spatial release of drugs in conjunction with external beam radiation therapy, potentially allowing for more effective treatment of deep-seated tumors with less systemic side effects.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Camundongos , Animais , Humanos , Cloridrato de Erlotinib/farmacologia , Cloridrato de Erlotinib/uso terapêutico , Vitamina B 12/uso terapêutico , Camundongos Nus , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/radioterapia , Carcinoma Ductal Pancreático/patologia , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/radioterapia , Neoplasias Pancreáticas/patologia , Linhagem Celular Tumoral
20.
Mol Genet Genomic Med ; 12(1): e2282, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37800653

RESUMO

BACKGROUND: Transcobalamin II (TCN2) defect is a rare metabolic disorder associated with a range of neurological manifestations, including mild developmental delay, severe intellectual disability, ataxia, and, in some cases, seizures. Cobalamin, an essential nutrient, plays a crucial role in central nervous system myelination. CLINICAL PRESENTATION: We present a family with an index patient who exhibited progressive neurodevelopmental regression starting at 9 months of age, accompanied by myoclonic seizures, ataxia, and tremor. No significant hematological abnormalities were observed. Exome sequencing analysis identified a novel homozygous mutation, c.3G>A - P(Met1I), affecting the acceptor site of intron 4 of the TCN2 gene (chromosome 22: 31003321, NM_000355.4), leading to likely pathogenic variant potentially affecting translation. Following treatment with hydroxocobalamin, the patient demonstrated partial clinical improvement. He has a sibling with overt hematological abnormalities and subtle neurological abnormalities who is homozygous to the same mutation. Both parents are heterozygous for the same mutation. CONCLUSIONS: In infants presenting with unexplained non-specific neurological symptoms, irrespective of classical signs of vitamin B12 deficiency, evaluation for TCN2 defect should be considered. Early diagnosis and appropriate management can lead to favorable outcomes.


Assuntos
Ataxia Cerebelar , Epilepsia Generalizada , Epilepsia , Humanos , Lactente , Masculino , Ataxia/tratamento farmacológico , Ataxia/genética , Mutação , Convulsões/tratamento farmacológico , Convulsões/genética , Transcobalaminas/genética , Transcobalaminas/metabolismo , Vitamina B 12/uso terapêutico
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