Normal prions as a new target of cobalamin (vitamin B12) in rat central nervous system

The Role of Vitamin B12 in the Management and Optimization of Treatment in Patients With Degenerative Cervical Myelopathy

STUDY DESIGN

Narrative review.

OBJECTIVES

To discuss the relationship between degenerative cervical myelopathy (DCM) and vitamin B12 deficiency. Specifically, it is the aim to outline the rational for future research into assessment and therapeutic optimization of vitamin B12 in the treatment of DCM.

METHODS

Literature review.

RESULTS

DCM is the commonest cause of spinal cord impairment, with an average age of presentation in the sixth decade. Patients at this age have also been reported to have a high prevalence of vitamin B12 deficiency, with estimates of up to 20% in the elderly. Vitamin B12 deficiency can result in subacute combined degeneration of the spinal cord (SACD), and several case reports have pointed to patients with both DCM and SACD. Both SACD and reversible compressive injury due to DCM necessitate remyelination in the spinal cord, a process that requires adequate vitamin B12 levels. Basic science research on nerve crush injuries have shown that vitamin B12 levels are altered after nerve injury and that vitamin B12 along with dexamethasone or nonsteroidal anti-inflammatory drugs can reduce Wallerian degeneration. Furthermore, it has been suggested that a combination of B-vitamins can reduce glutamate-induced neurotoxicity.

CONCLUSIONS

Given the high prevalence of clinical and subclinical vitamin B12 deficiency in the elderly, the role of vitamin B12 in myelination, and vitamin B12 deficiency as a differential diagnosis of DCM, it is important to investigate what role vitamin B12 levels play in patients with DCM in terms of baseline neurological function and whether optimization of vitamin B12 levels can improve surgical outcome. Furthermore, the routine assessment of vitamin B12 levels in patients considered for DCM surgery should be considered.

DTI correlates of cognition in conventional MRI of normal-appearing brain in patients with clinical features of subacute combined degeneration and biochemically proven vitamin B(12) deficiency

BACKGROUND AND PURPOSE

Vitamin B12 deficiency may cause neural injury that results in cognitive deficits. The main purpose of our study was to evaluate morphometric and microstructural changes in the brain and relate them to cognition in subacute combined degeneration of the spinal cord and patients with biochemically deficient vitamin B12.

MATERIALS AND METHODS

Fifty-one patients were recruited and underwent nerve-conduction velocity tests and routine hematologic examinations. Serum vitamin B12 and homocystine levels were also measured. All patients and 46 age- and sex-matched controls underwent cervical spine and brain MR imaging along with cognition tests. MR imaging included conventional scans and DTI. Voxel-based morphometry was performed for determining the WM and GM volumes, based on T1-weighted images. DTI measures that included fractional anisotropy, ADC, radial diffusivity, and axial diffusivity were determined by using tract-based statistics.

RESULTS

None of the patients showed any abnormality on conventional MR imaging. No significant changes in GM and WM volumes were observed in patients compared with controls. Significant reductions in the fractional anisotropy and an increase in ADC and radial diffusivity values were observed in multiple brain regions in patients compared with controls. These changes were confirmed on the region-of-interest analysis. Neuropsychological scores were significantly different in patients compared with controls and showed significant correlation with fractional anisotropy and radial diffusivity in a few brain regions.

CONCLUSIONS

Microstructural changes are seen in WM regions on DTI in patients with vitamin B12 deficiency and correlate with cognition scores. DTI can be used for objective assessment of microstructural changes in the brain in vitamin B12 deficiency.

Brain immune interactions and air pollution: macrophage inhibitory factor (MIF), prion cellular protein (PrP(C)), Interleukin-6 (IL-6), interleukin 1 receptor antagonist (IL-1Ra), and interleukin-2 (IL-2) in cerebrospinal fluid and MIF in serum differentiate urban children exposed to severe vs. low air pollution

Mexico City Metropolitan Area children chronically exposed to high concentrations of air pollutants exhibit an early brain imbalance in genes involved in oxidative stress, inflammation, innate and adaptive immune responses along with accumulation of misfolded proteins observed in the early stages of Alzheimer and Parkinson's diseases. A complex modulation of serum cytokines and chemokines influences children's brain structural and gray/white matter volumetric responses to air pollution. The search for biomarkers associating systemic and CNS inflammation to brain growth and cognitive deficits in the short term and neurodegeneration in the long-term is our principal aim. We explored and compared a profile of cytokines, chemokines (Multiplexing LASER Bead Technology) and Cellular prion protein (PrP(C)) in normal cerebro-spinal-fluid (CSF) of urban children with high vs. low air pollution exposures. PrP(C) and macrophage inhibitory factor (MIF) were also measured in serum. Samples from 139 children ages 11.91 ± 4.2 years were measured. Highly exposed children exhibited significant increases in CSF MIF (p = 0.002), IL6 (p = 0.006), IL1ra (p = 0.014), IL-2 (p = 0.04), and PrP(C) (p = 0.039) vs. controls. MIF serum concentrations were higher in exposed children (p = 0.009). Our results suggest CSF as a MIF, IL6, IL1Ra, IL-2, and PrP(C) compartment that can possibly differentiate air pollution exposures in children. MIF, a key neuro-immune mediator, is a potential biomarker bridge to identify children with CNS inflammation. Fine tuning of immune-to-brain communication is crucial to neural networks appropriate functioning, thus the short and long term effects of systemic inflammation and dysregulated neural immune responses are of deep concern for millions of exposed children. Defining the linkage and the health consequences of the brain / immune system interactions in the developing brain chronically exposed to air pollutants ought to be of pressing importance for public health.