OBJECTIVE Vitamin B12 is involved in the production of adrenaline from noradrenaline. It is the cofactor involved in catecholamine degradation and plays a role in myelin synthesis. The current study aimed to investigate the association between vitamin B12 levels and postural orthostatic tachycardia syndrome (POTS) during adolescence when accelerated myelin synthesis increases the vitamin B12 ne...

Objective(s): Methamphetamine (METH) is a powerful stimulant drug that directly affects the brain and induces neurological deficits. B12 is a water-soluble vitamin (vit) that is reported to attenuate neuronal degeneration. The goal of the present study is to investigate the effect of vitamin B12 on METH’s neurodegenerative changes.Materials and Methods: Two groups of 6 animals received METH (10...

Abstract Objective: Diabetic peripheral neuropathy (DPN) is one of the most common complications of diabetes. Beside the known factors such as hyperglycemia in the pathogenesis of this complication, other etiologies may play role in the pathogenesis of this complication. The aim of this study was the evaluation of the role of serum vitamin D and vitamin B12 levels in this process. Material a...

OBJECTIVE To assess the prevalence and clinical features of B12 deficiency in hypothyroid patients and to evaluate clinical response in symptoms to B12 replacement therapy. METHODS One hundred and sixteen hypothyroid patients from our endocrine clinic were evaluated for signs and symptoms of vitamin B12 deficiency. Laboratory parameters including Haemoglobin (Hb), MCV, Vitamin B12 levels and ...

Background: Elevated plasma vitamin B12 concentrations were identified as predictors of mortality in patients with oncologic, hepatic and renal diseases, and in elderly and critically ill medical patients. The association between vitamin B12 concentrations and in-hospital mortality in adult patients at nutritional risk has not been assessed. Methods: In this five-year prospective study, we inve...

OBJECTIVES To study vitamin B12 concentrations in patients with type 2 diabetes with and without metformin use and to identify risk factors and consequences of low vitamin B12 concentrations. RESEARCH DESIGN AND METHODS This study had a cross-sectional design. During eight weeks all patients with type 2 diabetes visiting the diabetic outpatient clinic of the Isala Clinics in Zwolle were appro...

Oxidative stress is implicated in various human diseases and conditions, such as a neurodegeneration, which is the major symptom of vitamin B12 deficiency, although the underlying disease mechanisms associated with vitamin B12 deficiency are poorly understood. Vitamin B12 deficiency was found to significantly increase cellular H2O2 and NO content in Caenorhabditis elegans and significantly decr...

Vitamin B12, a co-factor in methyl-group transfer, is important in maintaining DNA (deoxycytidine) methylation. Using two independent assays we examined the effect of vitamin B12-deficiency (plasma vitamin B12<148 pmol/L) on DNA methylation in women of childbearing age. Coagulated blood clot DNA from vitamin B12-deficient women had significantly (p<0.001) lower percentage deoxycytidine methylat...

BACKGROUND Vitamin B12 deficiency may have deleterious effects on end stage renal disease (ESRD) patients on maintenance hemodialysis, and may increase erythropoietin stimulating agent (ESA) resistance, yet little is known about its prevalence in this population. METHODS Serum vitamin B12 and methylmalonic acid (MMA) levels were drawn from ESRD patients prior to hemodialysis. All patients wit...

The minimal daily requirement of dietary vitamin B12 is defined as that amount which must be ingested in the diet to prevent the occurrence of megaloblastosis, anemia, or other manifestations of vitamin B12 deficiency. An attempt has been made to define this requirement by studying hematological responses to varying amounts of the vitamin in five south Indian subjects with vitamin B12 deficienc...