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1.
Aging (Albany NY) ; 16(9): 7856-7869, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38700503

RESUMEN

Vitamin B12 and folic acid could reduce blood homocysteine levels, which was thought to slow down the progression of Alzheimer's disease (AD), but previous studies regarding the effect of vitamin B12 and folic acid in treatment of AD have not reached conclusive results. We searched PubMed and Embase until January 12, 2023. Only randomized control trials involving participants clearly diagnosed with AD and who received vitamin B12 and folic acid were enrolled. Five studies that met the criteria were selected for inclusion in the meta-analysis. Changes in cognitive function were measured based on either the Mini-Mental State Examination (MMSE) or the Alzheimer's Disease Assessment Scale-Cognitive Subscale (ADAS-Cog). Changes in daily life function and the level of blood homocysteine were also investigated. After a 6-month treatment, administration of vitamin B12 and folic acid improved the MMSE scores more than placebo did (SMD = 0.21, 95% CI = 0.01 to 0.32, p = 0.04) but did not significantly affect ADAS-Cog scores (SMD = 0.06, 95% CI = -0.22 to 0.33, p = 0.68) or measures of daily life function. Blood homocysteine levels were significantly decreased after vitamin B12 and folic acid treatment. Participants with AD who received 6 months of vitamin B12 and folic acid supplementation had better MMSE scores but had no difference in ADAS-Cog scores. Daily life function did not improve after treatment.


Asunto(s)
Enfermedad de Alzheimer , Ácido Fólico , Homocisteína , Ensayos Clínicos Controlados Aleatorios como Asunto , Vitamina B 12 , Humanos , Ácido Fólico/uso terapéutico , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/sangre , Vitamina B 12/uso terapéutico , Vitamina B 12/sangre , Homocisteína/sangre , Cognición/efectos de los fármacos
2.
BMJ Case Rep ; 17(4)2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38663893

RESUMEN

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.


Asunto(s)
Dolor de Cuello , Radiculopatía , Deficiencia de Vitamina B 12 , Vitamina B 12 , Adulto , Humanos , Masculino , Vértebras Cervicales , Diagnóstico Diferencial , Dolor de Cuello/etiología , Radiculopatía/etiología , Radiculopatía/diagnóstico , Vitamina B 12/uso terapéutico , Deficiencia de Vitamina B 12/complicaciones , Deficiencia de Vitamina B 12/diagnóstico
3.
J Pediatr Endocrinol Metab ; 37(4): 380-386, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38436354

RESUMEN

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.


Asunto(s)
Errores Innatos del Metabolismo de los Aminoácidos , Anemia Macrocítica , Deficiencia de Vitamina B 12 , Recién Nacido , Humanos , Vitamina B 12/uso terapéutico , Transcobalaminas/genética , Estudios Retrospectivos , Deficiencia de Vitamina B 12/diagnóstico , Deficiencia de Vitamina B 12/tratamiento farmacológico , Deficiencia de Vitamina B 12/genética , Errores Innatos del Metabolismo de los Aminoácidos/tratamiento farmacológico , Diagnóstico Precoz
4.
Clin Nutr ; 43(4): 1025-1032, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38527394

RESUMEN

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.


Asunto(s)
Anemia Perniciosa , Deficiencias de Hierro , Deficiencia de Vitamina B 12 , Humanos , Anemia Perniciosa/complicaciones , Anemia Perniciosa/tratamiento farmacológico , Hierro , Deficiencia de Vitamina B 12/complicaciones , Deficiencia de Vitamina B 12/tratamiento farmacológico , Datos Preliminares , Vitamina B 12/uso terapéutico , Autoanticuerpos , Suplementos Dietéticos
5.
J Coll Physicians Surg Pak ; 34(3): 351-354, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38462874

RESUMEN

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.


Asunto(s)
Bencilaminas , Naftalenos , Eyaculación Prematura , Masculino , Humanos , Eyaculación Prematura/tratamiento farmacológico , Resultado del Tratamiento , Eyaculación , Vitamina B 12/uso terapéutico
6.
Am J Clin Nutr ; 119(3): 821-828, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38432716

RESUMEN

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.


Asunto(s)
Accidente Cerebrovascular , Vitaminas , Humanos , Vitamina B 12/uso terapéutico , Ácido Fólico/uso terapéutico , Vitamina B 6/uso terapéutico , Accidente Cerebrovascular/prevención & control , Suplementos Dietéticos
7.
J Small Anim Pract ; 65(5): 317-328, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38354724

RESUMEN

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.


Asunto(s)
Enfermedades de los Perros , Deficiencia de Vitamina B 12 , Vitamina B 12 , Animales , Perros , Femenino , Masculino , Administración Oral , Enfermedad Crónica , Enfermedades de los Perros/tratamiento farmacológico , Enfermedades Inflamatorias del Intestino/veterinaria , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Enfermedades Inflamatorias del Intestino/complicaciones , Estudios Prospectivos , Enteropatías Perdedoras de Proteínas/veterinaria , Enteropatías Perdedoras de Proteínas/tratamiento farmacológico , Resultado del Tratamiento , Vitamina B 12/administración & dosificación , Vitamina B 12/uso terapéutico , Vitamina B 12/sangre , Deficiencia de Vitamina B 12/veterinaria , Deficiencia de Vitamina B 12/tratamiento farmacológico
9.
Br J Community Nurs ; 29(3): 137-146, 2024 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-38421889

RESUMEN

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.


Asunto(s)
Enfermedades Cardiovasculares , Vitamina B 12 , Femenino , Humanos , Anciano , Vitamina B 12/uso terapéutico , Ácido Fólico/uso terapéutico , Suplementos Dietéticos , Enfermedades Cardiovasculares/tratamiento farmacológico , Evaluación de Resultado en la Atención de Salud
10.
Rheumatol Int ; 44(4): 737-741, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38294542

RESUMEN

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.


Asunto(s)
Enfermedades Reumáticas , Reumatología , Deficiencia de Vitamina B 12 , Humanos , Deficiencia de Vitamina B 12/complicaciones , Deficiencia de Vitamina B 12/diagnóstico , Deficiencia de Vitamina B 12/tratamiento farmacológico , Vitamina B 12/uso terapéutico , Enfermedades Reumáticas/complicaciones , Enfermedades Reumáticas/diagnóstico , Enfermedades Reumáticas/tratamiento farmacológico
11.
Mymensingh Med J ; 33(1): 303-306, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38163808

RESUMEN

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.


Asunto(s)
Anemia Perniciosa , Enfermedades Autoinmunes , Masculino , Humanos , Persona de Mediana Edad , Anemia Perniciosa/complicaciones , Anemia Perniciosa/diagnóstico , Vitamina B 12/uso terapéutico , Parestesia
12.
R I Med J (2013) ; 107(2): 13-15, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38285744

RESUMEN

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.


Asunto(s)
Enfermedades de la Médula Espinal , Degeneración Combinada Subaguda , Deficiencia de Vitamina B 12 , Masculino , Humanos , Óxido Nitroso/efectos adversos , Parestesia/inducido químicamente , Parestesia/complicaciones , Vitamina B 12/uso terapéutico , Deficiencia de Vitamina B 12/inducido químicamente , Deficiencia de Vitamina B 12/complicaciones , Deficiencia de Vitamina B 12/diagnóstico , Degeneración Combinada Subaguda/complicaciones , Enfermedades de la Médula Espinal/complicaciones , Ataxia/complicaciones
13.
Artículo en Inglés | MEDLINE | ID: mdl-38231988

RESUMEN

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.


Asunto(s)
Degeneración Combinada Subaguda , Trastornos Relacionados con Sustancias , Deficiencia de Vitamina B 12 , Humanos , Degeneración Combinada Subaguda/inducido químicamente , Degeneración Combinada Subaguda/complicaciones , Óxido Nitroso/efectos adversos , Deficiencia de Vitamina B 12/inducido químicamente , Deficiencia de Vitamina B 12/tratamiento farmacológico , Deficiencia de Vitamina B 12/complicaciones , Vitamina B 12/uso terapéutico , Vitamina B 12/farmacología , Trastornos Relacionados con Sustancias/complicaciones
16.
J Immunother ; 47(4): 117-122, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-37909180

RESUMEN

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.


Asunto(s)
Antineoplásicos , Neoplasias , Humanos , Masculino , Neoplasias/tratamiento farmacológico , Antineoplásicos/uso terapéutico , Supervivencia sin Progresión , Inmunoterapia , Vitamina B 12/uso terapéutico , Estudios Retrospectivos
17.
Chem Biol Interact ; 387: 110823, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38049026

RESUMEN

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.


Asunto(s)
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 1 , Fármacos Neuroprotectores , Ratas , Humanos , Animales , Lactante , Vitamina B 12/farmacología , Vitamina B 12/uso terapéutico , Ratas Sprague-Dawley , Estreptozocina/farmacología , Diabetes Mellitus Experimental/metabolismo , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéutico , Diabetes Mellitus Tipo 1/inducido químicamente , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Gliosis , Apoptosis
18.
Nutr Clin Pract ; 39(2): 356-365, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38030578

RESUMEN

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.


Asunto(s)
Choque , Vitamina B 12 , Adulto , Humanos , Vitamina B 12/uso terapéutico , Hidroxocobalamina/uso terapéutico , Choque/tratamiento farmacológico , Vasoconstrictores/uso terapéutico , Vitaminas/uso terapéutico
19.
Mol Pharm ; 21(1): 137-142, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-37989273

RESUMEN

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.


Asunto(s)
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Ratones , Animales , Humanos , Clorhidrato de Erlotinib/farmacología , Clorhidrato de Erlotinib/uso terapéutico , Vitamina B 12/uso terapéutico , Ratones Desnudos , Carcinoma Ductal Pancreático/tratamiento farmacológico , Carcinoma Ductal Pancreático/radioterapia , Carcinoma Ductal Pancreático/patología , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/radioterapia , Neoplasias Pancreáticas/patología , Línea Celular Tumoral
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