miR-21, miR-93, miR-191, miR-let-7b, and miR-499 Expression Level in Plasma and Cerebrospinal Fluid in Patients with Prolonged Disorders of Consciousness

In recent decades, significant progress has been achieved in understanding the mechanisms of disturbance and restoration of consciousness in patients after severe brain damage resulting in prolonged disorders of consciousness (pDOC). MicroRNAs (miRs) may be potential candidates as possible biomarkers for the classification of disease subtypes, and prognosis in patients with pDOC. The aim of the study was to analyze miRs expression levels (hsa-miR-21-5p, hsa-miR-93-5p, hsa-miR-191-5p, mmu-miR-499-5p, hsa-let-7b-5p) by a real-time polymerase chain reaction in plasma and cerebrospinal fluid (CSF) from patients with pDOC and to identify a potential biomarker for dividing patients into groups according to disease severity. We analyzed the levels of investigated miRs in pDOC patients, divided by etiology, CRSI, and the total group compared with controls. Our results showed that dividing patients with pDOC into groups according to the etiology of the disease resulted in the most significant differences in the levels of miR-93, -21, and -191 in CSF and plasma samples between groups of patients. Among the analyzed miRs, we did not find a marker that would help to distinguish VS/UWS patient groups from MCS. Examining of miRs as possible prognostic markers in patients with pDOC, the starting point seems to be the cause that led to the development of the disease.

[Magnetic resonance spectroscopy data in the prognosis of consciousness recovery in patients with vegetative state]

AIM

To study the prognostic value of magnetic resonance spectroscopy (MRS) in patients with vegetative state/unresponsive wakefulness syndrome (VS/UWS).

MATERIAL AND METHODS

Thirty-four patients with VS/UWS underwent multi-voxel MRS (thalamus, globus pallidus, putamen, internal capsules, fornix, brainstem, temporal and frontal cortex). Subjects were grouped according to etiology: 22 patients with traumatic brain injury (TBI) (group 1) and 12 patients with a hypoxia (group 2). The groups were matched by age and duration of UWS (mean 2, 3 months). The CRS-R was used to identify the first signs of consciousness during hospitalization and 6-12 months later. Outcomes of the patients with TBI were as follows: chronic VS/UWS (n=6), minimally conscious state (MCS) plus (n=9), emergence from MCS (EMCS) (n=7). Outcomes of the patients with hypoxia were: chronic vegetative state (n=10), minimally conscious state (MCS) (n=2).

RESULTS

The decrease in the NAA/Cr ratio in thalamus, capsula interna, temporal cortex are correlated with poor outcome in both groups. Higher rates of NAA/Cr in these structures are correlated with further recovery of consciousness. The decrease in the ratio of NAA Cr and NAA/NAA+Cho+Cr in the midbrain is correlated with poor outcome only in UWS with hypoxia.

CONCLUSION

The results suggest that the MRS allows to more accurately predicting the outcome in VS/UWS patients with hypoxic brain damage, as well as in UWS patients with TBI, who have recovered consciousness to the level of EMCS.

[Vegetative State: Difficulty in Identifying Consciousness and Predicting Outcome]

Article consists of literature review, authors experience of the application of neurovisualization and neurophysiological research methods to predict the recovery of consciousness in patients in vegetative state (VS). According to the literature data PET with FDG has higher sensitivity in the detection of signs of consciousness, then functional MRI (fMRI). The method fMRI allows assessing the functional activity of the brain in a state of rest and in response to stimulation with different modalities ― visual, auditory, etc (with the application of active and passive paradigm). A higher specificity in the detection of signs of consciousness have the methodology of fMRI with the active paradigm, at the same time, the absence of signs of consciousness according to the fMRI can not be charged as a basis for the conclusion of a poor prognosis in a particular patient. Neurophysiological tests (EEG, TMS, EP, etc) are more readily available and quite effective. Based on the literature analysis, the authors comes to the conclusion that neurovisualization and neurophysiological tests used in the prediction of the outcome of VS reflects the residual functional activity of different brain areas, in a context of diffuse brain damage, and the recovery of consciousness is usually combined with the restoring of the functional activity off the thalamocortical tracts, which activity, indirectly, is evaluated using these methods. In the authors' opinions, the main disadvantage in the interpretation of the is the lack of a common pathophysiological concept of the organization of brain functions in VS patients. The authors offer for the discussion their concept of stable pathological states of the brain, which is based on the works of Russian pathophysiologists.

Sporadic ALS associated with the D90A Cu,Zn superoxide dismutase mutation in Russia

Twenty blood samples from Russian patients (Moscow) with idiopathic motor neurone disease were analysed for mutations in the Cu,Zn superoxide dismutase (Cu,Zn SOD) gene. Two patients (10%) with the amyotrophic lateral sclerosis (ALS) form of the disease were found to have a disease-related mutation. One patient appears to have autosomal recessive adult-onset ALS associated with homozygosity for D90A and presents the characteristic phenotype of very slowly ascending paresis with both lower and upper motor neurone signs. Another patient, heterozygous for D90A, presents ALS with lumbar onset and rapid progression. This is the first report of a Cu,Zn SOD mutation in ALS in Russia.