Protein S-100B, neuron-specific enolase (NSE), myelin basic protein (MBP) and glial fibrillary acidic protein (GFAP) in cerebrospinal fluid (CSF) and blood of neurological patients

Fluid-Based Protein Biomarkers in Traumatic Brain Injury: The View from the Bedside

There has been an explosion of research into biofluid (blood, cerebrospinal fluid, CSF)-based protein biomarkers in traumatic brain injury (TBI) over the past decade. The availability of very large datasets, such as CENTRE-TBI and TRACK-TBI, allows for correlation of blood- and CSF-based molecular (protein), radiological (structural) and clinical (physiological) marker data to adverse clinical outcomes. The quality of a given biomarker has often been framed in relation to the predictive power on the outcome quantified from the area under the Receiver Operating Characteristic (ROC) curve. However, this does not in itself provide clinical utility but reflects a statistical association in any given population between one or more variables and clinical outcome. It is not currently established how to incorporate and integrate biofluid-based biomarker data into patient management because there is no standardized role for such data in clinical decision making. We review the current status of biomarker research and discuss how we can integrate existing markers into current clinical practice and what additional biomarkers do we need to improve diagnoses and to guide therapy and to assess treatment efficacy. Furthermore, we argue for employing machine learning (ML) capabilities to integrate the protein biomarker data with other established, routinely used clinical diagnostic tools, to provide the clinician with actionable information to guide medical intervention.

Extracellular proteins as potential biomarkers in Sepsis-related cerebral injury

Background

Sepsis can cause brain damage known as septic encephalopathy (SAE), which is linked to higher mortality and poorer outcomes. Objective clinical markers for SAE diagnosis and prognosis are lacking. This study aimed to identify biomarkers of SAE by investigating genes and extracellular proteins involved in sepsis-induced brain injury.

Methods

Extracellular protein differentially expressed genes (EP-DEGs) from sepsis patients' brain tissue (GSE135838) were obtained from Gene Expression Omnibus (GEO) and evaluated by protein annotation database. The function and pathways of EP-DEGs were examined using GO and KEGG. Protein-protein interaction (PPI) networks were built and crucial EP-DEGs were screened using STRING, Cytoscape, MCODE, and Cytohubba. The diagnostic and prognostic accuracy of key EP-DEGs was assessed in 31 sepsis patients' blood samples and a rat cecal ligation and puncture (CLP)-induced sepsis model. Cognitive and spatial memory impairment was evaluated 7-11 days post-CLP using behavioral tests. Blood and cerebrospinal fluid from 26 rats (SHAM n=14, CLP n=12) were collected 6 days after CLP to analyze key EP-DEGs.

Results

Thirty-one EP-DEGs from DEGs were examined. Bone marrow leukocytes, neutrophil movement, leukocyte migration, and reactions to molecules with bacterial origin were all enhanced in EP-DEGs. In comparison to the sham-operated group, sepsis rats had higher levels of MMP8 and S100A8 proteins in their venous blood (both p<0.05) and cerebrospinal fluid (p=0.0506, p<0.0001, respectively). Four important extracellular proteins, MMP8, CSF3, IL-6, and S100A8, were identified in clinical peripheral blood samples. MMP8 and S100A8 levels in the peripheral blood of sepsis patients were higher in SAE than in non-SAE. In comparison to MMP8, S100A8 had a higher area under the curve (AUC: 0.962, p<0.05) and a higher sensitivity and specificity (80% and 100%, respectively) than MMP8 (AUC: 0.790, p<0.05). High levels of S100A8 strongly correlated with 28-day mortality and the Glasgow Coma Scale (GCS) scores.

Conclusion

The extracellular proteins MMP8, CSF3, IL-6, and S100A8 may be crucial in the pathophysiology of SAE. S100A8 and MMP8 are possible biomarkers for SAE's onset and progression. This research may help to clarify the pathogenesis of SAE and improve the diagnosis and prognosis of the disease.

Senolytic therapy in mild Alzheimer's disease: a phase 1 feasibility trial

Cellular senescence contributes to Alzheimer's disease (AD) pathogenesis. An open-label, proof-of-concept, phase I clinical trial of orally delivered senolytic therapy, dasatinib (D) and quercetin (Q), was conducted in early-stage symptomatic patients with AD to assess central nervous system (CNS) penetrance, safety, feasibility and efficacy. Five participants (mean age = 76 + 5 years; 40% female) completed the 12-week pilot study. D and Q levels in blood increased in all participants (12.7-73.5 ng ml-1 for D and 3.29-26.3 ng ml-1 for Q). In cerebrospinal fluid (CSF), D levels were detected in four participants (80%) ranging from 0.281 to 0.536 ml-1 with a CSF to plasma ratio of 0.422-0.919%; Q was not detected. The treatment was well-tolerated, with no early discontinuation. Secondary cognitive and neuroimaging endpoints did not significantly differ from baseline to post-treatment further supporting a favorable safety profile. CSF levels of interleukin-6 (IL-6) and glial fibrillary acidic protein (GFAP) increased (t(4) = 3.913, P = 0.008 and t(4) = 3.354, P = 0.028, respectively) with trending decreases in senescence-related cytokines and chemokines, and a trend toward higher Aβ42 levels (t(4) = -2.338, P = 0.079). In summary, CNS penetrance of D was observed with outcomes supporting safety, tolerability and feasibility in patients with AD. Biomarker data provided mechanistic insights of senolytic effects that need to be confirmed in fully powered, placebo-controlled studies. ClinicalTrials.gov identifier: NCT04063124 .

Serum tau protein elevation in migraine: a cross-sectional case-control study

BACKGROUND

Migraine is a disorder associated with neuropeptide release, pain and inflammation. Tau protein has recently been linked to inflammatory diseases and can be influenced by neuropeptides such as CGRP, a key neurotransmitter in migraine. Here, we report serum concentrations of total-tau protein in migraine patients and healthy controls.

METHODS

In this cross-sectional study, interictal blood samples from n = 92 patients with episodic migraine (EM), n = 93 patients with chronic migraine (CM), and n = 42 healthy matched controls (HC) were studied. We assessed serum total-tau protein (t-tau) and for comparison neurofilament light chain protein (NfL), glial fibrillary acidic protein (GFAP), and ubiquitin carboxy-terminal hydrolase L (UCH-L1) concentrations using the Neurology 4-plex kit, on a single molecule array HD-X Analyzer (Quanterix Corp Lexington, MA). Matched serum/cerebrospinal fluid (CSF) samples were used for post-hoc evaluations of a central nervous system (CNS) source of relevant findings. We applied non-parametric tests to compare groups and assess correlations.

RESULTS

Serum t-tau concentrations were elevated in EM [0.320 (0.204 to 0.466) pg/mL] and CM [0.304 (0.158 to 0.406) pg/mL] patients compared to HC [0.200 (0.114 to 0.288) pg/mL] (p = 0.002 vs. EM; p = 0.025 vs. CM). EM with aura [0.291 (0.184 to 0.486 pg/mL); p = 0.013] and EM without aura [0.332 (0.234 to 0.449) pg/mL; p = 0.008] patients had higher t-tau levels than HC but did not differ between each other. Subgroup analysis of CM with/without preventive treatment revealed elevated t-tau levels compared to HC only in the non-prevention group [0.322 (0.181 to 0.463) pg/mL; p = 0.009]. T-tau was elevated in serum (p = 0.028) but not in cerebrospinal fluid (p = 0.760). In contrast to t-tau, all proteins associated with cell damage (NfL, GFAP, and UCH-L1), did not differ between groups.

DISCUSSION

Migraine is associated with t-tau elevation in serum but not in the CSF. Our clinical study identifies t-tau as a new target for migraine research.

Thyroid Hormone Transporters MCT8 and OATP1C1 Are Expressed in Pyramidal Neurons and Interneurons in the Adult Motor Cortex of Human and Macaque Brain

Monocarboxylate transporter 8 (MCT8) and organic anion transporter polypeptide 1C1 (OATP1C1) are thyroid hormone (TH) transmembrane transporters that play an important role in the availability of TH for neural cells, allowing their proper development and function. It is important to define which cortical cellular subpopulations express those transporters to explain why MCT8 and OATP1C1 deficiency in humans leads to dramatic alterations in the motor system. By means of immunohistochemistry and double/multiple labeling immunofluorescence in adult human and monkey motor cortices, we demonstrate the presence of both transporters in long-projection pyramidal neurons and in several types of short-projection GABAergic interneurons in both species, suggesting a critical position of these transporters for modulating the efferent motor system. MCT8 is present at the neurovascular unit, but OATP1C1 is only present in some of the large vessels. Both transporters are expressed in astrocytes. OATP1C1 was unexpectedly found, only in the human motor cortex, inside the Corpora amylacea complexes, aggregates linked to substance evacuation towards the subpial system. On the basis of our findings, we propose an etiopathogenic model that emphasizes these transporters' role in controlling excitatory/inhibitory motor cortex circuits in order to understand some of the severe motor disturbances observed in TH transporter deficiency syndromes.

Artemisinin upregulates neural cell adhesion molecule L1 to attenuate neurological deficits after intracerebral hemorrhage in mice

BACKGROUND AND PURPOSE

Intracerebral hemorrhage (ICH) is a subtype of stroke and results in neurological deficits in patients without any effective treatments. Artemisinin (ART), a well-known antimalarial Chinese medicine, exerts multiple essential roles in the central and peripheral nervous system due to its antioxidative and anti-inflammation properties. Neural cell adhesion molecule L1 (L1CAM, L1) is considered to be implicated in neural development, functional maintenance, and neuroprotection during disease. However, whether these two essential molecules are neuroprotective in ICH remains unclear.

METHODS

Therefore, the present study investigated the influence of ART on the recovery of neurological deficits in a mouse model of ICH induced by collagenase and the underlying mechanism.

RESULTS

It was revealed that ART is capable of upregulating L1 expression to alleviate brain edema, reduce oxidative stress, and inhibit inflammation to alleviate ICH-induced brain injury to improve the neurological outcome in mice suffering from ICH.

CONCLUSION

These results may lay the foundation for ART to be a novel candidate treatment for ICH.

Cerebrospinal fluid biomarkers and genetic factors associated with normal pressure hydrocephalus and Alzheimer’s disease: a narrative review

Background

Normal pressure hydrocephalus is a neurologic disease leading to enlargement of ventricles which is presented with gait and balance disturbance, cognitive decline, and urinary incontinence. Diagnosis of normal pressure hydrocephalus is challenging due to the late onset of signs and symptoms. In this review, we summarize the cerebrospinal fluid, plasma, pathology, and genetic biomarkers of normal pressure hydrocephalus and related disorders.

Body

Recently, cerebrospinal fluid and serum biomarkers analysis alongside gene analysis has received a lot of attention. Interpreting a set of serum and cerebrospinal fluid biomarkers along with genetic testing for candidate genes could differentiate NPH from other neurological diseases such as Alzheimer's disease, Parkinson's disease with dementia, and other types of dementia.

Conclusion

Better understanding the pathophysiology of normal pressure hydrocephalus through genetic studies can aid in evolving preventative measures and the early treatment of normal pressure hydrocephalus patients.

Potential Molecular Biomarkers of Central Nervous System Damage in Breast Cancer Survivors

Damage of the central nervous system (CNS), manifested by cognitive impairment, occurs in 80% of women with breast cancer (BC) as a complication of surgical treatment and radiochemotherapy. In this study, the levels of ICAM-1, PECAM-1, NSE, and anti-NR-2 antibodies which are associated with the damage of the CNS and the endothelium were measured in the blood by ELISA as potential biomarkers that might reflect pathogenetic mechanisms in these patients. A total of 102 patients enrolled in this single-center trial were divided into four groups: (1) 26 patients after breast cancer treatment, (2) 21 patients with chronic brain ischemia (CBI) and asymptomatic carotid stenosis (ICA stenosis) (CBI + ICA stenosis), (3) 35 patients with CBI but without asymptomatic carotid stenosis, and (4) 20 healthy female volunteers (control group). Intergroup analysis demonstrated that in the group of patients following BC treatment there was a significant increase of ICAM-1 (mean difference: −368.56, 95% CI −450.30 to −286.69, p < 0.001) and PECAM-1 (mean difference: −47.75, 95% CI −68.73 to −26.77, p < 0.001) molecules, as compared to the group of healthy volunteers. Additionally, a decrease of anti-NR-2 antibodies (mean difference: 0.89, 95% CI 0.41 to 1.48, p < 0.001) was detected. The intergroup comparison revealed comparable levels of ICAM-1 (mean difference: −33.58, 95% CI −58.10 to 125.26, p = 0.76), PECAM-1 (mean difference: −5.03, 95% CI −29.93 to 19.87, p = 0.95), as well as anti-NR-2 antibodies (mean difference: −0.05, 95% CI −0.26 to 0.16, p = 0.93) in patients after BC treatment and in patients with CBI + ICA stenosis. The NSE level in the group CBI + ICA stenosis was significantly higher than in women following BC treatment (mean difference: −43.64, 95% CI 3.31 to −83.99, p = 0.03). Comparable levels of ICAM-1 were also detected in patients after BC treatment and in the group of CBI (mean difference: −21.28, 95% CI −111.03 to 68.48, p = 0.92). The level of PECAM-1 molecules in patients after BC treatment was also comparable to group of CBI (mean difference: −13.68, 95% CI −35.51 to 8.15, p = 0.35). In conclusion, among other mechanisms, endothelial dysfunction might play a role in the damage of the CNS in breast cancer survivors.

Glial fibrillary acidic protein as blood biomarker for differential diagnosis and severity of major depressive disorder

Neuroinflammation has been connected to the pathophysiology of major depressive disorder (MDD) and neurochemical biomarkers of glial pathology could aid the diagnosis and might support patient stratification and monitoring in clinical trials. Our study aimed to determine the utility of glial fibrillary acidic protein (GFAP), a marker of astrocyte activation, for the differential diagnosis and monitoring of MDD. Employing Simoa technology we measured levels of GFAP in prospectively collected serum samples from 81 age-matched patients with MDD, schizophrenia (SZ), bipolar disorder (BP), and healthy controls (HC). Highest GFAP levels were determined for MDD. At a cut-off of 130 pg/ml, MDD could be discriminated with 87% sensitivity from SZ and BP (specificity 70%) and from HC (specificity 56%). GFAP levels increased with age (r = 0.5236, p = 0.0002) and with MDD severity quantified based on the Montgomery-Åsberg Depression Rating Scale (r = 0.4308, p = 0.0221). Neurofilament light chain serum levels were not different in the diagnostic groups and not associated with GFAP levels (r = 0.0911, p = 0.576) pointing to an independence of astrocyte activation on neurodegeneration. Our study provides first evidence that serum GFAP levels could improve the differential diagnosis of MDD and that depression severity could be objectively quantified using serum GFAP levels. Furthermore, serum GFAP might represent a marker to monitor astroglial pathology in the course of MDD.

YKL-40 and neuron-specific enolase in neurodegeneration and neuroinflammation

Neurodegenerative diseases comprise a large number of disorders with high impact on human health. Neurodegenerative processes are caused by various etiological factors and differ in their clinical presentation. Neuroinflammation is widely discussed as both a cause and a consequence in the manifestation of these disorders. The interplay between the two entities is considered as a major contributor to the ongoing disease progression. An attentive search and implementation of new and reliable markers specific for the processes of inflammation and degeneration is still needed. YKL-40 is a secreted glycoprotein produced by activated glial cells during neuroinflammation. Neuron-specific enolase (NSE), expressed mainly by neuronal cells, is a long-standing marker for neuronal damage. The aim of this review is to summarize, clarify, and evaluate the potential significance and relationship between YKL-40 and NSE as biomarkers in the monitoring and prognosis of a set of neurological diseases, such as Alzheimer's disease, Parkinson's disease, Huntington's disease, and multiple sclerosis. YKL-40 appears to be a more reliable biomarker in neurological diseases than NSE. The more prominent expression pattern of YKL-40 could be explained with the more obvious involvement of glial cells in pathological processes accompanying each neurodegenerative disease, whereas reduced NSE levels are likely related to low metabolic activity and increased death of neurons.

Serum glial fibrillary acidic protein and S100 calcium-binding protein B correlates cerebral vessel reactivity following carotid artery stenting

Using detection markers in serum has the advantages of simplicity, repeatability and the capability. This study combined the use of serum glial fibrillary acidic protein (GFAP) and S100B protein (S100B) with imaging tools to confirm the role of serum biomarkers in evaluating the cerebral vessel reactivity after carotid artery stenting (CAS). After CAS, the serum concentrations of GFAP and S100B increased to the peak at 24 h after operation, and then gradually decreased. The mean flow velocity (MFV) (pre-operation, post-operation, 30 days follow-up: 47.65 ± 17.24 cm/s, 62.37 ± 18.25 cm/s, 70.29 ± 16.89 cm/s; P < 0.05) and pulsatility index (PI) (pre-operation, post-operation, 30 days follow-up: 0.78 ± 0.21, 0.98 ± 0.19, 1.02 ± 0.20; P < 0.05) increased significantly in the ipsilateral middle cerebral artery after CAS. At the 30-day follow-up, the cerebrovascular reserve (CVR) (post-operation, 30 days follow-up: 27.47 ± 12.13 cm/s, 31.92 ± 10.94 cm/s; P < 0.05) improved significantly. In patients with different degrees of stenosis, the more severe the stenosis in the carotid artery, the more obvious the improvement of CVR at the 30 days of follow-up (CVR changes: 11.08 ± 7.95 cm/s, Kendall’s tau-b = 0.645, P < 0.001). And the serum concentrations of GFAP (r = − 0.629, P < 0.0001) and S100B (r = − 0.604, P < 0.0001) correlated negatively with CVR at 30 days after CAS. Therefore, we recommend using the biomarkers GFAP and S100B associated with imaging tools such as transcranial Doppler (TCD) and Magnetic resonance imaging (MRI) to evaluate the cerebral vessel reactivity following CAS.

Scalable Bio Marker Combinations for Early Stroke Diagnosis: A Systematic Review

Background: Acute stroke treatment is a time-critical process in which every minute counts. Laboratory biomarkers are needed to aid clinical decisions in the diagnosis. Although imaging is critical for this process, these biomarkers may provide additional information to distinguish actual stroke from its mimics and monitor patient condition and the effect of potential neuroprotective strategies. For such biomarkers to be effectively scalable to public health in any economic setting, these must be cost-effective and non-invasive. We hypothesized that blood-based combinations (panels) of proteins might be the key to this approach and explored this possibility through a systematic review. Methods: We followed the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) guidelines for systematic review. Initially, the broader search for biomarkers for early stroke diagnosis yielded 704 hits, and five were added manually. We then narrowed the search to combinations (panels) of the protein markers obtained from the blood. Results: Twelve articles dealing with blood-based panels of protein biomarkers for stroke were included in the systematic review. We observed that NR2 peptide (antibody against the NR2 fragment) and glial fibrillary acidic protein (GFAP) are brain-specific markers related to stroke. Von Willebrand factor (vWF), matrix metalloproteinase 9 (MMP-9), and S100β have been widely used as biomarkers, whereas others such as the ischemia-modified albumin (IMA) index, antithrombin III (AT-III), and fibrinogen have not been evaluated in combination. We herein propose the following new combination of biomarkers for future validation: panel 1 (NR2 + GFAP + MMP-9 + vWF + S100β), panel 2 (NR2 + GFAP + MMP-9 + vWF + IMA index), and panel 3 (NR2 + GFAP + AT-III + fibrinogen). Conclusions: More research is needed to validate, identify, and introduce these panels of biomarkers into medical practice for stroke recurrence and diagnosis in a scalable manner. The evidence indicates that the most promising approach is to combine different blood-based proteins to provide diagnostic precision for health interventions. Through our systematic review, we suggest three novel biomarker panels based on the results in the literature and an interpretation based on stroke pathophysiology.

Associations of Serum Cytokine Levels and Interleukin-6-572C/G Polymorphism with Myelin Damage in Chinese Children with Autism Spectrum Disorder

Increasing evidence suggests that immunological disturbances and abnormalities in axonal myelination are involved in the pathophysiology of autism spectrum disorder (ASD). The present study aimed to determine the role of cytokines in myelin damage in Chinese children with ASD and the role of cytokine dysregulation, myelin damage, and cytokine polymorphisms in ASD in Chinese children. The present case-control study included 98 ASD subjects and 252 typically developing (TD) controls; the levels of serum cytokines and myelin basic protein (MBP) were determined using enzyme-linked immunosorbent assay. Cytokine polymorphisms were genotyped using polymerase chain reaction-restriction fragment length polymorphism analysis. Autistic clinical manifestations were assessed by the Childhood Autism Rating Scale (CARS). The results showed that serum levels of interleukin (IL)-1β, IL-2R, IL-6, IL-8, and MBP were higher in children with ASD compared with those in TD children. In individuals with ASD, serum MBP level was significantly positively associated with the CARS total score, and serum levels of IL-1β, IL-2R, IL-6, and MBP demonstrated positive correlations. The data identified IL-6*MBP as a factor that influenced the risk of ASD, and IL-2R*MBP was identified as a factor that influenced symptom severity, which influenced auxiliary diagnosis of ASD. The presence of the interleukin-6-572CC genotype was associated with significantly higher serum levels of IL-6 and MBP but did not influence the risk and symptom severity of ASD. Therefore, the results suggested inflammatory responses and myelin damage in Chinese children with ASD. Cytokine dysregulation influenced myelin damage in ASD; moreover, the interactions of the cytokines and myelin damage influenced the risk and symptom severity of ASD. The IL-6-572C/G genotypes may be associated with myelin damage in ASD by influencing the circulating level of IL-6.

Cerebrospinal fluid findings and hypernatremia in COVID-19 patients with altered mental status

BACKGROUND

The objective of the study was to assess the cerebrospinal fluid (CSF) findings in COVID-19 patients.

AIMS

This was an observational retrospective cohort from electronic medical records of hospitalized patients (n = 2655) with confirmed COVID-19 between February 15, 2020, and April 15, 2020, in 182 hospitals from a large health system in the USA. The review of data yielded to a total of 79 patients in 20 hospitals who had CSF analysis.

METHODS

Outcomes during hospitalization, including hospital length of stay, disease severity, ventilator time, and in-hospital death were recorded. Independent variables collected included patient demographics, diagnoses, laboratory values, and procedures.

RESULTS

A total of 79 patients underwent CSF analysis. Of these, antigen testing was performed in 73 patients. Ten patients had CSF analysis for general markers such as total protein, cell count, glucose, clarity, and color. Seven of the 10 cases (70%) had normal total cell count and normal white blood cell count in CSF. Sixty-three percent (5/8) had elevated total protein. Two patients had normal levels of lactate dehydrogenase (LDH) and 1 patient had significantly elevated (fourfold) neuron-specific enolase (NSE) level in CSF.

CONCLUSION

Unlike bacterial infections, viral infections are less likely to cause remarkable changes in CSF glucose, cell count, or protein. Our observations showed no pleocytosis, but mild increase in protein in the CSF of the COVID-19 patients. The fourfold elevation of NSE may have diagnostic/prognostic value as a biomarker in CSF for COVID-19 patients who have altered mental status.

Detection and diagnostic value of serum NSE and S100B protein levels in patients with seizures associated with mild gastroenteritis: A retrospective observational study

Benign convulsions with mild gastroenteritis (CwG) and febrile seizures (FS) associated with mild gastroenteritis are 2 different diseases in the spectrum of seizures associated with mild gastroenteritis. However, specific and useful indicators for the identification of the 2 diseases are lacking. A retrospective analysis was performed to compare the serum neuronal-specific enolase (NSE) and S100B protein levels between patients with these 2 diseases to evaluate the value of NSE and S100B for differential diagnosis between these 2 diseases.The clinical data and NSE and S100B protein levels of 81 children with seizure-associated mild gastroenteritis were collected. According to the axillary temperature at the time of convulsions, all patients were classified into an afebrile seizure (AFS) group, hereafter called the CwG group (n = 46), and a febrile seizure group (FS group, n = 35).The serum NSE level was higher in the CwG group than in the FS group (14.046 (11.095, 19.266) pg/ml and 9.034 (7.158, 12.165) pg/ml, respectively, P < .001); however, the serum S100B protein levels in the CwG and the FS group were not significantly different (P > .05). Receiver operating characteristic (ROC) curve analysis showed that the area under the curve (AUC) for NSE was 0.806, P = .000, which was statistically significant. The Youden index was largest (0.605) for a serum NSE cut-off value of 10.460 pg/ml, which yielded a sensitivity and specificity of 89% and 71%, respectively, for prediction of a CwG diagnosis.NSE may contribute to the differential diagnosis of CwG and FS associated with mild gastroenteritis.

Can Neuron Specific Enolase Be a Diagnostic Biomarker for Neuronal Injury in COVID-19?

Neuron specific enolase (NSE) is a biomarker for neuronal injury. However, increased levels in cerebrospinal fluid (CSF) and serum is associated with the clinical outcome in patients with head injury, ischemic stroke, intracerebral hemorrhage, cardiac arrest, anoxic encephalopathy, encephalitis, brain metastasis, and status epilepticus.

Recently, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, which started in China, rapidly evolved into the coronavirus disease 2019 (COVID-19) pandemic. Patients with COVID-19 have a wide range of symptoms varying from mild upper respiratory symptoms to severe illness requiring mechanical ventilation. While coronaviruses primarily target the human respiratory system, neurological symptoms are also observed in some patients. These include symptoms such as loss of taste and olfaction and diseases like cerebrovascular disorders including ischemic stroke and hemorrhages, encephalopathies, Guillain‐Barré syndrome and acute disseminated encephalomyelitis.

Here we report an observation from a patient whose NSE levels increased approximately four-fold in CSF. This finding was accompanied by increased white blood cell count and elevated protein in CSF indicating neuroinflammation. Thus, we suggest that NSE may be used as a CSF biomarker in COVID-19 patients with encephalopathy.

Inflammation but not programmed cell death is activated in methamphetamine-dependent patients: Relevance to the brain function

Animal studies have shown that methamphetamine (MA) induces neurodegeneration through programmed cell death, however, the effects of MA on human brain and the extent of induced neural degeneration is not well understood. Given that the dose and duration of MA administration differ in animals and humans, we evaluated MA effects on active users considering brain damage mechanisms. Nineteen active MA-dependent patients and 18 healthy controls performed the color-word Stroop task, during fMRI and their blood samples were collected. Human enzyme-linked immunosorbent assays (ELISA) and quantitative PCR were applied to measure circulating proteins and miRNAs involved in various programmed cell death pathways (apoptosis, necroptosis, and autophagy), brain damage and neuroinflammation. Results showed the performance deficit in color-word Stroop task in MA abusers as well as higher activations of the right inferior and middle temporal gyri detected by fMRI. Structural MRI revealed increased white matter volume in MA-dependent patients in the superior and medial frontal gyri, and left/right middle temporal gyrus. Molecular analyses detected no significant differences in the plasma levels of the studied proteins and miRNAs of MA-dependent patients and controls except the higher levels of MBP, S100B, and TNFα in MA abusers. Results showed that MA induced physiological and structural changes accompanied by inflammation and release of damage-associated molecules in MA-dependent patients.

Platform for micro-invasive membrane-free biochemical sampling of brain interstitial fluid

Neurochemical dysregulation underlies many pathologies and can be monitored by measuring the composition of brain interstitial fluid (ISF). Existing in vivo tools for sampling ISF do not enable measuring large rare molecules, such as proteins and neuropeptides, and thus cannot generate a complete picture of the neurochemical connectome. Our micro-invasive platform, composed of a nanofluidic pump coupled to a membrane-free probe, enables sampling multiple neural biomarkers in parallel. This platform outperforms the state of the art in low-flow pumps by offering low volume control (single stroke volumes, <3 nl) and bidirectional fluid flow (<100 nl/min) with negligible dead volume (<30 nl) and has been validated in vitro, ex vivo, and in vivo in rodents. ISF samples (<1.5 μL) can be processed via liquid chromatography-tandem mass spectrometry. These label-free liquid biopsies of the brain could yield a deeper understanding of the onset, mechanism, and progression of diverse neural pathologies.

Effect of Polydatin on Neurological Function and the Nrf2 Pathway during Intracerebral Hemorrhage

This study investigates the effect of polydatin on the neurological function of cerebral hemorrhage rats and on the Nrf2 pathway of the endogenous antioxidant system in tissues around cerebral hematoma. Further, the study also aims to provide solid insights for clinical diagnosis and treatment. A total of 54 SPF grade male Wistar rats were divided into three groups: the sham group, model group, and polydatin group. Various parameters such as neurological deficit score, brain water content, pathological morphology, oxidative stress index content, Nrf2, NQO1, HO-1 mRNA expression, and the expression of HO-1, Nrf2, and kelch-like epichlorohydrin-1 (Keap1) protein were observed. Compared with the sham group, the mNSS score and brain water content of rats in the model group increased significantly after dosing (P < 0.05). When compared with the model group, the mNSS score and brain water content of rats in the polydatin group decreased significantly after dosing (P < 0.05). Compared with the other group, the serum NSE content of rats in the polydatin group decreased (P < 0.05). An increase was observed in the contents of NO, SOD, MDA, GSSG, and GSH in the brain tissue of rats in the model group when compared with the sham group. Compared with the model group, the contents of NO and MDA in the brain tissue of rats in the polydatin group decreased, while the contents of SOD, GSSG, and GSH increased (P < 0.05). The relative expressions of Nrf2, NQO1, and HO-1mRNA in the brain tissue of rats in the polydatin group was relatively high compared with both groups (P < 0.05). Polydatin can improve the neurological function of ICH rats and reduce the oxidative stress response by regulating the Nrf2-ARE pathway and downstream gene expression. This study preliminarily discussed the relevant mechanism of polydatin in the treatment of ICH rats, thus providing a theoretical reference to ICH treatment.

Temperature-sensitive bone mesenchymal stem cells combined with mild hypothermia reduces neurological deficit in rats of severe traumatic brain injury

BACKGROUND

To explore the combined influences of temperature-sensitive bone mesenchymal stem cells (tsBMSCs) and mild hypothermia (MH) on neurological function and glucose metabolism in rats with severe traumatic brain injury (TBI).

METHODS

SD rats were randomly divided into sham, TBI, TBI + MH, TBI + BMSCs and TBI + MH +tsBMSCs groups. Then, the brain water content, serum-specific proteins (S100β, NSE, LDH, and CK), and blood glucose at different time points were measured. Furthermore, GLUT-3 expression was detected by Western blotting, and apoptotic rate was determined by TUNEL staining.

RESULTS

After TBI rat establishment, the brain injury resulted in significant increases in mNSS scores and brain water content, and upregulations in serum levels of S100β, NSE, LDH and CK, and blood glucose, with the elevated cell apoptotic rate in the injured cortex. However, these changes were reversed by MH alone, BMSCs alone, or combination treatment of MH and tsBMSCs in varying degrees, and the combination treatment was superior to the treatment with BMSCs or MH alone.

CONCLUSION

Combination therapy of tsBMSCs and MH can reduce the neuronal apoptosis in severe TBI rats, with the suppression of serum biomarkers and hyperglycemia, contributing to the recovery of neurological functions.

ABBREVIATIONS

tsBMSCs: temperature-sensitive bone mesenchymal stem cells; MH: mild hypothermia; TBI: traumatic brain injury; mNSS: modified Neurological Severity Score.

Adaptive Immunity Regulation and Cerebral Ischemia

Stroke is a disease that occurs due to a sudden interruption of the blood supply to the brain. It is a leading cause of death and disability worldwide. It is well-known that the immune system drives brain injury following an episode of ischemic stroke. The innate system and the adaptive system play distinct but synergistic roles following ischemia. The innate system can be activated by damage-associated molecular patterns (DAMPs), which are released from cells in the ischemic region. Damaged cells also release various other mediators that serve to increase inflammation and compromise the integrity of the blood–brain barrier (BBB). Within 24 h of an ischemic insult, the adaptive immune system is activated. This involves T cell and B cell-mediated inflammatory and humoral effects. These cells also stimulate the release of various interleukins and cytokines, which can modulate the inflammatory response. The adaptive immune system has been shown to contribute to a state of immunodepression following an ischemic episode, and this can increase the risk of infections. However, this phenomenon is equally important in preventing autoimmunity of the body to brain antigens that are released into the peripheral system as a result of BBB compromise. In this review, we highlight the key components of the adaptive immune system that are activated following cerebral ischemia.

Neuron specific enolase as a marker of seizure related neuronal injury

BACKGROUND

and purpose: Neuron specific enolase (NSE) is an established biomarker of neuronal damage. It is not clear how much seizures contribute to the neuronal damage, morbidity or mortality in critically ill neurology patients. The aim of this study is to determine the impact of seizures on neuronal injury in critically ill neurology patients by using neuron specific enolase as a biomarker.

MATERIAL AND METHODS

Forty patients with clinical evidence of acute central nervous system disease associated with seizures were included as critically ill neurology patients with seizures [CINPS] (age in years 38.8 ± 17.54, mean ± SD; 22 males) and 43 age and sex-matched acute central nervous system disease without seizures were recruited as critically ill neurology patients [CINP] (age in years 37.84 ± 17.38 years mean ± SD; 24 males) The serum NSE assays were performed in CINPS (within 24 h of last seizure) and in CINP using an enzyme immunoassay kit.

RESULTS

The level of serum neuron specific enolase was significantly higher in CINP with seizures compared to those without seizures. The length of ICU stay was more prolonged in those with seizures. There was a close correlation between the NSE levels and frequency of seizures. There was no significant difference in the mortality between both the groups.

CONCLUSIONS

NSE a marker of neuronal injury was elevated in patients with acute central nervous system diseases. It is significantly higher in patients with seizures in comparison to those without seizures. This warrants further studies to document aggressive treatment of seizures in acute neurologically ill patients can reduce neuronal damage.

Using serum s100-β protein as a biomarker for comparing silent brain injury in carotid endarterectomy and carotid artery stenting

BACKGROUND

S100-β protein has been introduced as a sensitive biomarker of silent cerebral injury. This study compares its serum levels before, during, and 24 hours after carotid artery stenting (CAS) and carotid endarterectomy (CEA).

METHODS

We measured serum level of S100-β in arterial blood before (S100Ba), during (S100Bb), and 24 hours after (S100Bc) CAS and CEA. We assessed differences in S100-β levels using non-parametric tests. We analyzed the relationship between carotid plaque type (echolucency) and S100-β protein level. We also examined its relation to the oximetry results in the CEA group (ipsilateral and contralateral).

RESULTS

Thirty patients were enrolled, including 15 CAS and 15 CEA patients, with no significant differences in baseline atherosclerotic characteristics. There was no significant difference in S100Ba or S100Bb levels between CAS and CEA patients. However, a significant difference was found in S100Bc: 331.3 pg/mL (IQ range 56.4-583.5) for CAS vs. 76.3 pg/mL (IQ range 29.7-117.4) for CEA (P=0.01). Type I and II plaques were associated with the higher S100Bc levels in CAS (P=0.048). S100Bc was higher in CEA patients when the contralateral cerebral hemisphere had oximetry values less than 60% (P=0.043).

CONCLUSIONS

Our study suggests that CAS might produce silent brain injury. Moreover, vulnerable plaques might be associated with higher levels of S100-β protein, especially in CAS. This pilot study demonstrates that S100-β is a useful biomarker for silent brain injury in carotid revascularization. Large scale studies are still needed to confirm these findings.

Hyperacute changes in blood mRNA expression profiles of rats after middle cerebral artery occlusion: Towards a stroke time signature

Stroke evolution is a highly dynamic but variable disease which makes clinical decision making difficult. Biomarker discovery programs intended to aid clinical decision making have however largely ignored the rapidity of stroke evolution. We have used gene array technology to determine blood mRNA expression changes over the first day after stroke in rats. Blood samples were collected from 8 male spontaneously hypertensive rats at 0, 1, 2, 3, 6 and 24h post stroke induction by middle cerebral artery occlusion. RNA was extracted from whole blood stabilized in PAXgene tubes and mRNA expression was detected by oligonucleotide Affymetrix microarray. Using a pairwise comparison model, 1932 genes were identified to vary significantly over time (p≤0.5x10^-7) within 24h after stroke. Some of the top20 most changed genes are already known to be relevant to the ischemic stroke physiopathology (e.g. Il-1R, Nos2, Prok2). Cluster analysis showed multiple stereotyped and time dependent profiles of gene expression. Direction and rate of change of expression for some profiles varied dramatically during these 24h. Profiles with potential clinical utility including hyper acute or acute transient upregulation (with expression peaking from 2 to 6h after stroke and normalisation by 24h) were identified. We found that blood gene expression varies rapidly and stereotypically after stroke in rats. Previous researchers have often missed the optimum time for biomarker measurement. Temporally overlapping profiles have the potential to provide a biological “stroke clock” able to tell the clinician how far an individual stroke has evolved.

Effects of Kudiezi Injection on Serum Inflammatory Biomarkers in Patients with Acute Cerebral Infarction

BACKGROUND

Kudiezi injection is a traditional Chinese medicine for acute cerebral infarction, but the exact mechanisms are poorly understood.

OBJECTIVE

To investigate the mechanisms of Kudiezi injection on the inflammatory response in the treatment of acute cerebral infarction.

METHODS

This was a prospective study of patients with acute cerebral infarction within 48 h of onset and treated between July 2012 and July 2016 at three hospitals in China. The patients were randomized to routine treatments (control group) versus routine treatments and Kudiezi injection (Kudiezi group). The National Institutes of Health Stroke Score was assessed on days 1, 3, 5, 7, and 14. The patients were tested for serum levels of pro- and anti-inflammatory cytokines (S100 calcium-binding protein B, neuron-specific enolase, interleukin-6, interleukin-10, interleukin-18, and matrix metaloproteinase-9; by enzyme-linked immunosorbent assay) immediately after admission and on days 3, 5, and 14.

RESULTS

Stroke scores were improved in both groups from days 1 to 14. On days 5 and 7, stroke scores in the Kudiezi group were lower than in the control group (P < 0.05). Compared with controls, the Kudiezi group had lower serum S100 calcium-binding protein B on day 14; higher interleukin-6 and interleukin-10 on day 3; lower interleukin-6 and interleukin-18 on day 5; and lower interleukin-18 and matrix metaloproteinase-9 on day 14.

CONCLUSION

Kudiezi injection could lead to early reduction of interleukin-6, interleukin-18, matrix metaloproteinase-9, neuron-specific enolase, and S100 calcium-binding protein B levels and increases of interleukin-10 levels in patients with acute ischemic stroke. This trial is registered with ClinicalTrials.gov NCT01636154.

Post-mortem biochemistry of NSE and S100B: A supplemental tool for detecting a lethal traumatic brain injury?

PURPOSE

Traumatic brain injury (TBI) is a very common entity that leads to numerous fatalities all over the world. Therefore, forensic pathologists are in desperate need of supplemental methodological tools for the diagnosis of TBI in everyday practice besides the standard autopsy. The present study determined post-mortem neuron specific enolase (NSE) and S100 calcium-binding protein B (S100B) levels as biological markers of an underlying TBI in autopsy cases.

METHODS

Paired serum and CSF samples of 92 fatalities were collected throughout routine autopsies. Afterwards, the marker levels were assessed using commercially available immunoassays (ECLIA, Roche Diagnostics). For statistical analysis, we compared the TBI cases to three control groups (sudden natural death by acute myocardial infarction, traumatic death without impact on the head, cerebral hypoxia). Moreover, the TBI cases were subdivided according to their survival time of the trauma. Brain specimens have been collected and stained immunohistochemically against the aforementioned proteins to illustrate their typical cellular staining patterns with an underlying TBI compared to non-TBI fatalities.

PRINCIPAL RESULTS

CSF NSE and S100B levels were elevated after TBI compared to all control groups (p < 0.001). Although this finding can already be investigated among the TBI cases dying immediately subsequent to the trauma, the marker levels in CSF increase with longer survival times until a peak level within the first three days after trauma. There is a strong correlation between both marker levels in CSF (r = 0.67). The presence or absence of cerebral tissue contusion following the initial trauma does not seem to affect the CSF levels of both proteins (p > 0.05). Post-mortem serum levels of both proteins were not elevated in TBI cases compared to controls (p > 0.05). Former elaborated cut-off values in CSF were confirmed and were only exceeded when a TBI survival time of at least 30 min was reached.

MAJOR CONCLUSIONS

The present results report that post-mortem NSE and S100B CSF levels are significantly elevated subsequent to a fatal TBI.

Cerebrospinal fluid biomarkers profile of idiopathic normal pressure hydrocephalus

Idiopathic normal pressure hydrocephalus (iNPH) is a disabling neurological disorder whose potential treatability is significantly limited by diagnostic uncertainty. In fact, typical clinical presentation occurs at late phases of disease, when CSF shunting could be ineffective. In recent years, measurement of different CSF proteins, whose concentration directly reflects neuropathological changes of CNS, has significantly improved both diagnostic timing and accuracy of neurodegenerative disease. Unfortunately iNPH lacks neuropathological hallmarks allowing the identification of specific disease biomarkers. However, neuropathology of iNPH is so rich and heterogeneous that many processes can be tracked in CSF, including Alzheimer's disease core pathology, subcortical degeneration, neuroinflammation and vascular dysfunction. Indeed, a huge number of CSF biomarkers have been analyzed in iNPH patients, but a unifying profile has not been provided yet. In this brief survey, we thus attempted to summarize the main findings in the field of iNPH CSF biomarkers, aimed at outlining a synthetic model. Although defined cut-off values for biomarkers are not available, a better knowledge of CSF characteristics may definitely assist in diagnosing the disease.

Glial fibrillary acidic protein as a prognostic marker of acute ischemic stroke

Background:

We investigated the association between serum levels of glial fibrillary acidic protein (GFAP) and stroke functional outcomes in a cohort of 286 patients with acute ischemic stroke (AIS).

Methods:

We prospectively studied 286 patients with AIS who were admitted within 24 h after the onset of symptoms. Serum levels of GFAP and National Institutes of Health Stroke Scale (NIHSS) were measured at admission. The primary end point was stroke functional outcome among 1-year after stroke onset. We used logistic regression models to assess the relationship between GFAP levels and stroke outcomes.

Results:

The GFAP level was obtained with a median value of 0.18 (interquartile ranges (IQRs): 0.09–0.28) ng/ml. In multivariable models adjusted for age, gender, and other risk factors, GFAP levels were associated with an increased risk of a NIHSS>6 (odds ratio (OR) = 1.55; 95% confidence interval (CI): 1.16–1.89; p = 0.012). The poor outcome distribution across the GFAP quartiles ranged between 12.7% (first quartile) and 70.4% (fourth quartile). After adjusting for other established risk factors, in multivariate models comparing the Q3 and Q 4 quartiles against the Q1 of the GFAP, the levels of GFAP were associated with poor outcome, and the adjusted risk of poor outcome increased by 211% (3.11[1.80–5.05], p < 0.001) and 522% (6.22[2.98–11.83], p < 0.001), respectively. Interestingly, GFAP improved the ability of NIHSS score to diagnose poor outcomes (area under the curve [AUC] of the combined model 0.82; 95% CI: 0.77–0.88; p = 0.02).

Conclusion:

GFAP levels are a novel and complementary biomarker to predict functional outcome 1 year after AIS

Biomarkers of Cerebral Injury and Inflammation in Pediatric Tuberculous Meningitis

Background

Tuberculous meningitis (TBM) leads to death or disability in half the affected individuals. Tools to assess severity and predict outcome are lacking. Neurospecific biomarkers could serve as markers of the severity and evolution of brain injury, but have not been widely explored in TBM. We examined biomarkers of neurological injury (neuromarkers) and inflammation in pediatric TBM and their association with outcome.

Methods

Blood and cerebrospinal fluid (CSF) of children with TBM and hydrocephalus taken on admission and over 3 weeks were analyzed for the neuromarkers S100B, neuron-specific enolase (NSE), and glial fibrillary acidic protein (GFAP), in addition to multiple inflammatory markers. Results were compared with 2 control groups: patients with (1) a fatty filum (abnormal filum terminale of the spinal cord); and (2) pulmonary tuberculosis (PTB). Imaging was conducted on admission and at 3 weeks. Outcome was assessed at 6 months.

Results

Data were collected from 44 patients with TBM (cases; median age, 3.3 [min-max 0.3-13.1] years), 11 fatty filum controls (median age, 2.8 [min-max 0.8-8] years) and 9 PTB controls (median age, 3.7 [min-max 1.3-11.8] years). Seven cases (16%) died and 16 (36%) had disabilities. Neuromarkers and inflammatory markers were elevated in CSF on admission and for up to 3 weeks, but not in serum. Initial and highest concentrations in week 1 of S100B and NSE were associated with poor outcome, as were highest concentration overall and an increasing profile over time in S100B, NSE, and GFAP. Combined neuromarker concentrations increased over time in patients who died, whereas inflammatory markers decreased. Cerebral infarcts were associated with highest overall neuromarker concentrations and an increasing profile over time. Tuberculomas were associated with elevated interleukin (IL) 12p40, interferon-inducible protein 10, and monocyte chemoattractant protein 1 concentrations, whereas infarcts were associated with elevated tumor necrosis factor α, macrophage inflammatory protein 1α, IL-6, and IL-8.

Conclusions

CSF neuromarkers are promising biomarkers of injury severity and are predictive of mortality. An increasing trend suggested ongoing brain injury, even though markers of inflammation declined with treatment. These findings could offer novel insight into the pathophysiology of TBM.

Electroacupuncture improves neurobehavioral function and brain injury in rat model of intracerebral hemorrhage

Acupuncture has been widely used as a treatment for stroke in China for a long time. Recently, studies have demonstrated that electroacupuncture (EA) can accelerate intracerebral hemorrhage (ICH)-induced angiogenesis in rats. In the present study, we investigated the effect of EA on neurobehavioral function and brain injury in ICH rats. ICH was induced by stereotactic injection of collagenase type I and heparin into the right caudate putamen. Adult ICH rats were randomly divided into the following three groups: model control group (MC), EA at non-acupoint points group (non-acupoint EA) and EA at Baihui and Dazhui acupoints group (EA). The neurobehavioral deficits of ICH rats were assessed by modified neurological severity score (mNSS) and gait analysis. The hemorrhage volume and glucose metabolism of hemorrhagic foci were detected by PET/CT. The expression levels of MBP, NSE and S100-B proteins in serum were tested by ELISA. The histopathological features were examined by haematoxylin-eosin (H&E) staining. Apoptosis-associated proteins in the perihematomal region were observed by immunohistochemistry. EA treatment significantly promoted the recovery of neurobehavioral function in ICH rats. Hemorrhage volume reduced in EA group at day 14 when compared with MC and non-acupoint EA groups. ELISA showed that the levels of MBP, NSE and S100-B in serum were all down-regulated by EA treatment. The brain tissue of ICH rat in the EA group was more intact and compact than that in the MC and non-acupoint groups. In the perihematomal regions, the expression of Bcl-2 protein increased and expressions of Caspase-3 and Bax proteins decreased in the EA group vs MC and non-acupoint EA groups. Our data suggest that EA treatment can improve neurobehavioral function and brain injury, which were likely connected with the absorption of hematoma and regulation of apoptosis-related proteins.

The role of magnesium sulfate in the intensive care unit

Magnesium (Mg) has been developed as a drug with various clinical uses. Mg is a key cation in physiological processes, and the homeostasis of this cation is crucial for the normal function of body organs. Magnesium sulfate (MgSO4) is a mineral pharmaceutical preparation of magnesium that is used as a neuroprotective agent. One rationale for the frequent use of MgSO4 in critical care is the high incidence of hypomagnesaemia in intensive care unit (ICU) patients. Correction of hypomagnesaemia along with the neuroprotective properties of MgSO4 has generated a wide application for MgSO4 in ICU.

Capacity of Human Dental Follicle Cells to Differentiate into Neural Cells In Vitro

The dental follicle is an ectomesenchymal tissue surrounding the developing tooth germ. Human dental follicle cells (hDFCs) have the capacity to commit to differentiation into multiple cell types. Here we investigated the capacity of hDFCs to differentiate into neural cells and the efficiency of a two-step strategy involving floating neurosphere-like bodies for neural differentiation. Undifferentiated hDFCs showed a spindle-like morphology and were positive for neural markers such as nestin, β-III-tubulin, and S100β. The cellular morphology of several cells was neuronal-like including branched dendrite-like processes and neurites. Next, hDFCs were used for neurosphere formation in serum-free medium containing basic fibroblast growth factor, epidermal growth factor, and B27 supplement. The number of cells with neuronal-like morphology and that were strongly positive for neural markers increased with sphere formation. Gene expression of neural markers also increased in hDFCs with sphere formation. Next, gene expression of neural markers was examined in hDFCs during neuronal differentiation after sphere formation. Expression of Musashi-1 and Musashi-2, MAP2, GFAP, MBP, and SOX10 was upregulated in hDFCs undergoing neuronal differentiation via neurospheres, whereas expression of nestin and β-III-tubulin was downregulated. In conclusion, hDFCs may be another optimal source of neural/glial cells for cell-based therapies to treat neurological diseases.

[Value of serum S100B protein and neuron-specific enolase levels in predicting the severity of hand, foot and mouth disease]

OBJECTIVE

To study the value of serum S100B protein and neuron-specific enolase (NSE) levels in predicting the severity of hand, foot and mouth disease (HFMD).

METHODS

Ninety children with HFMD were classified into three groups: common type, severe type, and critical type (n=30 each). Thirty healthy children were randomly selected as the control group. ELISA was used to measure serum levels of S100B protein and NSE before and at 7 days after treatment. The receiver operating characteristic (ROC) curve was used to evaluate the prediction efficiency of S100B protein and NSE for the severity of HFMD.

RESULTS

The critical type group had significant increases in the serum levels of S100B protein and NSE compared with the other three groups (P<0.01). The severe type group had significant increases in serum levels of S100B protein and NSE compared with the common type and control groups (P<0.01). The critical type and severe type groups had significant reductions in serum levels of S100B protein and NSE after treatment (P<0.05). Serum S100B protein had the highest Youden value of 0.611 at the cut-off value of 0.445 μg/L, with a sensitivity of 61% and a specificity of 100%, in the prediction of serious HFMD (including severe type and critical type HFMD). Serum NSE had the highest Youden value of 0.533 at the cut-off value of 5.905 μg/L, with a sensitivity of 80% and a specificity of 73%, in the prediction of serious HFMD. Combined measurements of these two parameters had a sensitivity of 86% and a specificity of 73% and had the highest predictive value for serious HFMD.

CONCLUSIONS

The serum levels of S100B protein and NSE help to predict the severity and treatment outcomes of HFMD. Combined measurements of these two parameters has a higher predictive value for serious HFMD.

Selected CSF biomarkers indicate no evidence of early neuroinflammation in Huntington disease

Objective:

To investigate CSF biomarkers of neuroinflammation and neurodegeneration in Huntington disease (HD) gene-expansion carriers compared to controls and to investigate these biomarkers in association with clinical HD rating scales and disease burden score.

Methods:

We collected CSF from 32 premanifest and 48 manifest HD gene-expansion carriers and 24 gene-expansion negative at-risk controls. We examined biomarkers of neuroinflammation (matrix metalloproteinase 9, C-X-C motif chemokine 13, terminal complement complex, chitinase-3-like-protein 1 [CHI3L1], and osteopontin [OPN]) and neurodegeneration (microtubule-associated protein tau, neurofilament light polypeptide [NFL], and myelin basic protein [MBP]). The study was approved by the Ethics Committee of the Capital Region of Denmark (H2-2011-085) and written informed consent was obtained from each participant before enrollment.

Results:

NFL was the only biomarker that increased in premanifest stages and no evidence of early involvement of neuroinflammation in HD was found. However, we found that the biomarkers for neurodegeneration, MBP and tau, increased during the disease course in manifest HD gene-expansion carriers and were associated with an increase of the neuroinflammation biomarkers CHI3L1 and OPN. Tau was also increased in all gene-expansion carriers with psychiatric symptoms compared to gene-expansion carriers without psychiatric symptoms.

Conclusions:

Neuroinflammation, which seems not to be an early event in our cohort, may be secondary to neurodegeneration in late HD. NFL is a possible disease burden correlate in HD, reflecting neuronal loss even before motor symptom onset, and may be useful as a dynamic biomarker in intervention studies.

Peripheral biomarkers of stroke: Focus on circulatory microRNAs

Stroke is the second leading cause of death in the world. Stroke occurs when blood flow stops, and that stoppage results in reduced oxygen supply to neurons in the brain. The occurrence of stroke increases with age, but anyone at any age can suffer from stroke. Recent research has implicated multiple cellular changes in stroke patients, including oxidative stress and mitochondrial dysfunction, inflammatory responses, and changes in mRNA and proteins. Recent research has also revealed that stroke is associated with modifiable and non-modifiable risk factors. Stroke can be controlled by modifiable risk factors, including diet, cardiovascular, hypertension, smoking, diabetes, obesity, metabolic syndrome, depression and traumatic brain injury. Stroke is the major risk factor for vascular dementia (VaD) and Alzheimer's disease (AD). The purpose of this article is to review the latest developments in research efforts directed at identifying 1) latest developments in identifying biomarkers in peripheral and central nervous system tissues, 2) changes in microRNAs (miRNAs) in patients with stroke, 3) miRNA profile and function in animal brain, and 4) protein biomarkers in ischemic stroke. This article also reviews research investigating circulatory miRNAs as peripheral biomarkers of stroke.

Oxidative stress, protein modification and Alzheimer disease

Alzheimer disease (AD) is a progressive neurodegenerative disease that affects the elderly population with complex etiology. Many hypotheses have been proposed to explain different causes of AD, but the exact mechanisms remain unclear. In this review, we focus attention on the oxidative-stress hypothesis of neurodegeneration and we discuss redox proteomics approaches to analyze post-mortem human brain from AD brain. Collectively, these studies have provided valuable insights into the molecular mechanisms involved both in the pathogenesis and progression of AD, demonstrating the impairment of numerous cellular processes such as energy production, cellular structure, signal transduction, synaptic function, mitochondrial function, cell cycle progression, and degradative systems. Each of these cellular functions normally contributes to maintain healthy neuronal homeostasis, so the deregulation of one or more of these functions could contribute to the pathology and clinical presentation of AD. In particular, we discuss the evidence demonstrating the oxidation/dysfunction of a number of enzymes specifically involved in energy metabolism that support the view that reduced glucose metabolism and loss of ATP are crucial events triggering neurodegeneration and progression of AD.

Effect of Tempol on Cerebral Resuscitation Caused by Asphyxia-Induced Cardiac Arrest

BACKGROUND

This study was conducted to investigate the effect and mechanism of the nitrogen oxide 4-hydroxy- 2,2,6,6-tetramethylpiperidine (Tempol) on cerebral resuscitation caused by asphyxia-induced cardiac arrest.

METHODS

Airway occlusion-induced asphyxia at the end of expiration was used to establish the rat cerebral ischaemia-hypoxia injury model. A total of 90 adult male Sprague-Dawley rats were randomly divided into the three groups. The Tempol and conventional cardiopulmonary resuscitation (CPR) groups were further divided into four subgroups according to different time points.

RESULTS

After cerebral ischaemia, independent heart rate following asphyxia appeared earlier, and the success rate of primary recovery and the neurological function score of rats were higher in the Tempol group than in the conventional CPR group. The serum neuron-specific enolase (NSE) levels in the Tempol and conventional CPR groups were significantly higher within 6 to 48 h than that in the blank control group. The serum NSE level was significantly lower in the Tempol group than the conventional CPR group.

CONCLUSIONS

After global cerebral ischaemia-hypoxia, the antioxidant Tempol improved cerebral resuscitation by reducing oxidative stress injuries and post-CPR cerebral damage. The NSE level can be used as an early detection index in the diagnosis of global cerebral ischaemia-hypoxia injuries.

KEY WORDS

Cerebral ischemia; Neuron-specific enolase; Rats; Tempol.

Neuron-specific enolase levels in drug-naïve young adults with major depressive disorder

The aim of this study is to assess neuron-specific enolase (NSE) levels and clinical features in subjects with major depressive disorder (MDD). This is a cross-sectional study with drug-naïve young adults with MDD (aged 18-29 years). Serum levels of NSE were assessed using the electrochemiluminescence method. MDD diagnosis, suicidal ideation, and time of disease were assessed using the Structured Clinical Interview for DSM-IV (SCID). The Hamilton Depression Rating Scale (HDRS) and Hamilton Anxiety Rating Scale (HARS) were used to assess depressive and anxiety symptoms. No relationship was observed between NSE levels and severity of depressive and anxiety symptoms, time of disease, and suicidal ideation. These results suggest that NSE serum levels were not associated with clinical features of MDD among drug-naïve young adults.

The neonatal levels of TSB, NSE and CK-BB in autism spectrum disorder from Southern China

Background" Autism spectrum disorder (ASD) is a serious neurodevelopmental disorder that impairs a child's ability to communicate with others. It also includes restricted repetitive behaviors, interests and activities. Symptoms manifest before the age of 3. In the previous studies, we found structural abnormalities of the temporal lobe cortex. High spine densities were most commonly found in ASD subjects with lower levels of cognitive functioning. In the present study, we retrospectively analyzed medical records in relation to the neonatal levels of total serum bilirubin (TSB), neuron-specific enolase (NSE), creatine kinase brain band isoenzyme (CK-BB), and neonatal behavior in ASD patients from Southern China.

METHODS

A total of 80 patients with ASD (ASD group) were screened for this retrospective study. Among them, 34 were low-functioning ASD (L-ASD group) and 46 were high-functioning ASD (H-ASD group). Identification of the ASD cases was confirmed with a Revised Autism Diagnostic Inventory. For comparison with ASD cases, 80 normal neonates (control group) were selected from the same period. Biochemical parameters, including TSB, NSE and CK-BB in the neonatal period and medical records on neonatal behavior were collected.

RESULTS

The levels of serum TSB, NSE and CK-BB in the ASD group were significantly higher when compared with those from the control group (P < 0.01, or P < 0.05). The amounts of serum TSB, NSE and CK-BB in the L-ASD group were significantly higher when compared with those in the H-ASD group (P < 0.01, or P < 0.05). The Neonatal Behavioral Assessment Scale (NBAS) scores in the ASD group were significantly lower than that in the control group (P < 0.05). Likewise, the NBAS scores in the L-ASD group were significantly lower than that in the H-ASD group (P < 0.05). There was no association between serum TSB, NSE, CK-BB and NBAS scores (P > 0.05) in the ASD group.

CONCLUSIONS

The neonatal levels of TSB, NSE and CK-BB in ASD from Southern China were significantly higher than those of healthy controls. These findings need to be investigated thoroughly by future studies with large sample.

Current status of fluid biomarkers in mild traumatic brain injury

Mild traumatic brain injury (mTBI) affects millions of people annually and is difficult to diagnose. Mild injury is insensitive to conventional imaging techniques and diagnoses are often made using subjective criteria such as self-reported symptoms. Many people who sustain a mTBI develop persistent post-concussive symptoms. Athletes and military personnel are at great risk for repeat injury which can result in second impact syndrome or chronic traumatic encephalopathy. An objective and quantifiable measure, such as a serum biomarker, is needed to aid in mTBI diagnosis, prognosis, return to play/duty assessments, and would further elucidate mTBI pathophysiology. The majority of TBI biomarker research focuses on severe TBI with few studies specific to mild injury. Most studies use a hypothesis-driven approach, screening biofluids for markers known to be associated with TBI pathophysiology. This approach has yielded limited success in identifying markers that can be used clinically, additional candidate biomarkers are needed. Innovative and unbiased methods such as proteomics, microRNA arrays, urinary screens, autoantibody identification and phage display would complement more traditional approaches to aid in the discovery of novel mTBI biomarkers.

Myelin basic protein and ischemia modified albumin levels in acute ischemic stroke cases

Objective:

To investigate early diagnostic effects of serum myelin basic protein (MBP) and ischemic modified albumin (IMA) levels in patients with ischemic stroke.

Methods:

Fifty patients who presented to an emergency service with acute ischemic stroke between June 2013 to March 2014 were evaluated with the National Institute of Health Stroke Scale (NIHSS) and diffusion-weighted magnetic resonance imaging (MRI). Thirty four healthy cases were included as control group. All patients’ serum IMA and MBP level were assessed.

Results:

Mean IMA value was 0.52±0.25 cases with acute ischemic stroke and serum IMA levels were significantly higher than the control group (p<0.01). No statistical significance was observed between acute ischemic stroke group and control group related to the MBP serum levels (P>0.05). Statistically significant correlation was detected between the volumes of diffusion restriction on MRI and NIHSS score (P=0.002, r=0.43) and IMA (P=0.015, r=0.344) levels.

Conclusions:

We have found that serum IMA levels are elevated in acute ischemic stroke cases and these levels are correlated with the ischemic tissue volume. MBP levels do not increase in early period of stroke cases.

Neonatal chlorpyrifos exposure induces loss of dopaminergic neurons in young adult rats

Increasing epidemiological and toxicological evidence suggests that pesticides and other environmental exposures may be associated with the development of Parkinson's disease (PD). Chlorpyrifos (CPF) is a widely used organophosphorous pesticide with developmental neurotoxicity. Its neurotoxicity, notably on the monoamine system, suggests that exposure of CPF may induce dopaminergic neuronal injury. We investigated whether neonatal exposure to CPF contributes to initiation and progression of dopaminergic neurotoxicity and explored the possible underlying mechanisms. The newborn rats were administrated 5 mg/kg CPF subcutaneously from postnatal day (PND) 11 to PND 14 daily. The effect of CPF on dopaminergic neurons, microglia, astrocyte, nuclear factor-κB (NF-κB) p. 65 and p. 38 mitogen-activated protein kinase (MAPK) signaling pathways was analyzed in the substantia nigra of rats at 12h, 24h, 72 h, 16d and 46 d after exposure. CPF-treated rats exhibited significant reduction of dopaminergic neurons at 16d and 46 d after exposure, and a significant increase in the expression of microglia and astrocytes in the substantia nigra after CPF exposure. Intense activation of NF-κB p. 65 and p. 38 MAPK inflammatory signaling pathways was observed. Our findings indicate that neonatal exposure to CPF may induce long-term dopaminergic neuronal damage in the substantia nigra mediated by the activation of inflammatory response via NF-κB p. 65 and p. 38 MAPK pathways in the nigrostriatal system.

Prognostic value of cerebrospinal fluid free fatty acid levels in patients with acute ischemic stroke

In this study, prognostic value of cerebrospinal fluid (CSF) free fatty acid (FFA) levels in patients confirmed with acute ischemic stroke (AIS) was evaluated in a Chinese population. A prospective cohort designed study was conducted at our hospital of the Emergency department from November, 2012 to September, 2014. The National Institutes of Health Stroke Scale (NIHSS) score on admission was applied to assess CSF levels of FFA and specific severity degree of stroke. Evaluation of the prognostic outcomes of those stroke patients used the modified Rankin scale scores at 90-days. Logistic regression analysis analyzed the prognostic value of FFA. NIHSS score results suggested a positive relationship between levels of CSF FFA levels and severity of stroke. There was an obviously higher trend of CSF FFA levels in patients with CE stroke than those of the non-CE stroke patients, with statistically difference (P < 0.05). Further, CSF FFA levels were evidently lower in those 73 patients with favorable outcome when compared to those with unfavorable outcomes [0.21(IQR, 0.11-0.28) mmol/L vs. 0.36 (IQR, 0.27-0.50) mmol/L, P < 0.0001, P < 0.0001]. Multivariate analysis results after possible confounders adjustment indicated that there was an increased risk of unfavorable outcome associated with CSF FFA levels ≥0.29 mmol/L (OR 5.12, 95%CI: 2.35-10.28; P < 0.0001). Collectively, CSF level of FFA at admission was suggested to be a useful, independent short-term prognostic marker in Chinese patient with AIS.

Effect of magnesium on functional outcome and paraclinical parameters of patients undergoing supratentorial craniotomy for brain tumors: a randomized controlled trial

BACKGROUND

Several studies have demonstrated that magnesium (Mg) plays an important role in the prevention and treatment of central nervous system (CNS) insults. In this study, we tested the effect of intravenous magnesium sulfate (MgSO4) on the outcome of patients with brain tumors who underwent craniotomy. The outcome was defined clinically as the Barthel index score and paraclinically as blood levels of NSE (neuron-specific enloase) and S100Β protein.

METHODS

Sixty patients were randomly divided into two groups of 30 patients: the treatment and control groups. In the treatment group, 5 g of MgSO4 in normal saline was infused in 6 h 2 days before surgery, and the same dosage was repeated the day before and during surgery. The control group received placebo. Serum S100Β and NSE concentrations were measured at baseline before administration of magnesium, before surgery, and on the 2nd postoperative day. The Barthel index score was evaluated and registered before surgery, 3, and 6 months after the operation.

RESULTS

The study results showed a significant change in S100Β protein levels before and after surgery (p < 0.05), but we could not find similar results for NSE protein and the Barthel index score. There was a correlation between NSE protein and the Barthel index.

CONCLUSIONS

The results of this study revealed that administration of intravenous MgSO4 before and during surgery is safe and effective in reducing S100B protein levels in patients undergoing supratentorial craniotomy for brain tumors. Further studies to elucidate the pathophysiology of brain injuries and role of magnesium are warranted.

Increased sleep need and daytime sleepiness 6 months after traumatic brain injury: a prospective controlled clinical trial

Post-traumatic sleep-wake disturbances are common after acute traumatic brain injury. Increased sleep need per 24 h and excessive daytime sleepiness are among the most prevalent post-traumatic sleep disorders and impair quality of life of trauma patients. Nevertheless, the relation between traumatic brain injury and sleep outcome, but also the link between post-traumatic sleep problems and clinical measures in the acute phase after traumatic brain injury has so far not been addressed in a controlled and prospective approach. We therefore performed a prospective controlled clinical study to examine (i) sleep-wake outcome after traumatic brain injury; and (ii) to screen for clinical and laboratory predictors of poor sleep-wake outcome after acute traumatic brain injury. Forty-two of 60 included patients with first-ever traumatic brain injury were available for follow-up examinations. Six months after trauma, the average sleep need per 24 h as assessed by actigraphy was markedly increased in patients as compared to controls (8.3 ± 1.1 h versus 7.1 ± 0.8 h, P < 0.0001). Objective daytime sleepiness was found in 57% of trauma patients and 19% of healthy subjects, and the average sleep latency in patients was reduced to 8.7 ± 4.6 min (12.1 ± 4.7 min in controls, P = 0.0009). Patients, but not controls, markedly underestimated both excessive sleep need and excessive daytime sleepiness when assessed only by subjective means, emphasizing the unreliability of self-assessment of increased sleep propensity in traumatic brain injury patients. At polysomnography, slow wave sleep after traumatic brain injury was more consolidated. The most important risk factor for developing increased sleep need after traumatic brain injury was the presence of an intracranial haemorrhage. In conclusion, we provide controlled and objective evidence for a direct relation between sleep-wake disturbances and traumatic brain injury, and for clinically significant underestimation of post-traumatic sleep-wake disturbances by trauma patients.

Circulating biomarkers in malignant melanoma

Melanoma is an aggressive tumor with increasing incidence worldwide. Biomarkers are valuable tools to minimize the cost and improve efficacy of treatment of this deadly disease. Serological markers have not widely been introduced in routine clinical practice due to their insufficient diagnostic sensitivity and specificity. It is likely that the lack of objective responses with traditional treatment hinder biomarker research and development in melanoma. Recently, new drugs and therapies have, however, emerged in advanced melanoma with noticeable objective response ratio and survival. In this new scenario, serological tumor markers should be revisited. In addition, other potential circulating biomarkers such as cell-free DNA, exosomes, microRNA, and circulating tumor cells have also been identified. In this review, we summarize classical and emerging tumor markers and discuss their possible roles in emerging therapeutics.