Marker Of Neural Injury Research Articles

Serum neurofilament light release levels as marker of neurotoxicity in general anesthesia versus hypnosis: A prospective non-randomized trial

Background: Whether general anesthetics induce neurotoxicity is unclear. Objectives: We hypothesized that serum neurofilament light (NfL) release, a marker of neural injury, would not be different in patients receiving general anesthesia (GA) compared to hypnosis. Design: Prospective, non-randomized. Setting: Tertiary university hospital. Methods: Patients undergoing breast cancer or thyroid/parathyroid surgery were enrolled. Propofol and remifentanil were used for GA. For hypnosis, only low dose remifentanil was allowed. Main outcome measures: NfL was measured at baseline, at day 1 and at postoperative visit. At preoperative and postoperative visit, patients performed a Montreal Cognitive Assessment (MoCA) test. Primary outcome was absolute change in NfL at day 1 between groups. Results: Among 100 included patients, 51 were in GA and 49 in hypnosis group. There were 26/49 (53%) breast cancer patients in hypnosis group and 13/51 (26%) in GA arm, p = 0.005. Baseline NfL was higher in the hypnosis group (p = 0.050). We subtracted log-transformed baseline NfL from postoperative NfL to analyze normalized values as absolute change. The mean normalized value at day 1 (primary endpoint) was 0.02 (± 0.11) in the GA and 0.03 (± 0.20) in the hypnosis group; p = 0.979 [d = 0.16, 95% CI: -0.40 to 0.39]. In a linear mixed-effects model including variables that influenced baseline NfL (advanced age, higher creatinine values, breast cancer), mean difference (95 % CI) in absolute change of log NfL at day 1 between both groups was 0.007 (- 0.04 to 0.06); p = 0.791. A change in MoCA as compared to baseline was not different between groups (p = 0.761). Conclusions: Our results show that there was no statistical or clinical difference in postoperative NfL release between GA and hypnosis. GA with propofol was not associated with a different risk of neural injury compared to hypnosis. Trial registration: NCT04500236.

Adrenergic receptors blockade alleviates dexamethasone-induced neurotoxicity in adult male Wistar rats: Distinct effects on β-arrestin2 expression and molecular markers of neural injury

BackgroundDexamethasone-induced neurotoxicity has been previously reported. However, the molecular mechanisms are still not completely understood.ObjectivesThe current work aimed to investigate the modulatory effects of α- and β-adrenergic receptors on dexamethasone-induced neurotoxicity in rats focused on changes in β-arrestin2 and molecular markers of neural injury in cerebral cortex.MethodsMale Wistar rats were subcutaneously injected with dexamethasone (10 mg/kg/day) for 7 days to induce neural injury in the cerebral cortex. The experiment involved 5 groups: control, dexamethasone, carvedilol, propranolol, and doxazosin. In the last 3 groups, drugs were given 2 hours before dexamethasone injection. At the end of experiment, brain samples were collected for measurement of brain derived neurotrophic factor (BDNF), glial fibrillary acidic protein (GFAP), kinase activity of protein kinase B (Akt), diacylglycerol (DAG), α-smooth muscle actin (α-SMA), Smad3, β-amyloid and phospho-tau protein levels in addition to histopathological examination of brain tissue using hematoxylin-eosin, Nissl, and Sirius red stains. Moreover, β-arrestin2 levels in the cerebral cortex were measured using immunohistochemical examination.ResultsDexamethasone slightly reduced brain weight and significantly decreased BDNF, Akt kinase activity and β-arrestin2 but markedly induced degeneration of cortical neurons and significantly increased GFAP, DAG, α-SMA, Smad3, β-amyloid and phospho-tau protein levels compared to controls. Carvedilol, propranolol, and doxazosin reversed all dexamethasone-induced molecular changes and slightly ameliorated the histopathological changes. Carvedilol significantly increased brain weight and β-arrestin2 levels compared to dexamethasone, propranolol, and doxazosin groups.Conclusionblocking α- and/or β-adrenergic receptors alleviate dexamethasone-induced neurotoxicity despite their distinct effects on β-arrestin2 levels in the cerebral cortex.Graphical abstract

Abstract 13579: Serum Neural Biomarkers and Neuroimaging Markers in Neonates With Congenital Heart Disease Undergoing Cardiac Surgery

Introduction: Congenital heart disease (CHD) patients requiring neonatal cardiopulmonary bypass (CPB) surgery often experience abnormal neurodevelopment. Open heart surgery and anesthesia induce changes in the developing brain concomitant with an increase in the level of neuromarkers. The aim of this study is to assess the relationship between neuromarkers, brain dysplasia and neurodevelopmental outcomes for CHD patients undergoing neonatal CPB. Hypothesis: Neuromarkers and neuroimaging brain dysplasia can predict the neurodevelopmental outcomes for CHD patients undergoing neonatal CPB. Methods: 42 neonates with CHD requiring CPB were included in this prospective, observational study. Using the Neurology 4-Plex A Assay, serum levels of glial fibrillary acidic protein (GFAP), ubiquitin carboxyl-terminal hydrolase L1 (UCH-L1), neurofilament light (NF-L), and Tau protein were measured pre-operatively and at 0 hours, 24 hours, and 48 hours post-operatively. Brain MRIs were obtained in 24 neonates. Neurodevelopment testing was completed at 6 months to 36 months of age using the Bayley-III Scales of infant. Findings of brain MRI were scored using an internally developed scoring system which evaluates the brains structures individually on degrees of dysplasia, hypoplasia, and abnormalities, as well as providing a comprehensive assessment of overall brain development combining the individual structural abnormalities into a composite total brain dysplasia score (TBDS). Results: Bayley-III scales were negatively correlated with NF-L and Tau. For UCH-L1, a positive correlation was seen at immediate postop. Hemorrhage is associated with low language score (P=0.009) and elevated UCH-L1 levels at 24 hours and 48 hours. Infraction (P=0.0375) and lower maturation (P=0.03) are associated with low fine motor scores. Lower maturation is related to more domains below average (P=0.01). Infarction is associated with high postoperative Tau level (P=0.04).TBDS is associated with high levels of GFAP, NFL-1, and decreased language development. Conclusion: A negative correlation of Tau and NF-L to Bayley-III scales was consistent with their known roles as markers of neural injury. High NF-L and GFAP are associated with brain dysplasia.

NCMP-24. PRE-INFUSION NEUROFILAMENT LIGHT CHAIN (NFL) LEVELS PREDICT THE DEVELOPMENT OF IMMUNE EFFECTOR CELL-ASSOCIATED NEUROTOXICITY SYNDROME (ICANS)

Abstract Neurological side effects after chimeric antigen receptor-modified (CAR) T cell therapy are common and potentially devastating. Termed immune effector cell-associated neurotoxicity syndrome (ICANS), symptoms range from mild encephalopathy to diffuse cerebral edema. No predictive biomarkers exist to identify individuals at risk for developing ICANS. Serum neurofilament light chain (NfL) is a well-established marker of neural injury known to dynamically change in neuro-inflammatory disorders (e.g. multiple sclerosis). We hypothesized individuals undergoing CAR T cell therapy who ultimately developed ICANS would have early and sustained elevations in serum NfL. We performed a retrospective analysis of serum samples from 11 individuals treated with tisagenlecleucel or axicabtagene ciloleucel (mean age 61.3, 18% female, 27% ICANS, all with peak severity score 3). Most individuals had a longitudinal sampling at baseline, pre-infusion, post-transfusion day (PTD) 1, PTD 3, PTD 7, PTD 14, and PTD 30. Serum NfL were assayed using a Simoa HD-1/HD-X kit (QuanterixTM). We found that individuals who developed ICANS had early and sustained elevations in serum NfL levels at baseline (p = 0.0075), pre-infusion (p = 0.0172), and PTD 3 (p = 0.0026) and PTD 30 (p = 0.0066). All group comparisons survived multiple comparison testing using false-discovery rate (FDR). Receiver operating characteristic (ROC) curve classification by logistic regression of serum NfL revealed an area under the curve (AUC) of 1.0 with a cut-off of 44 pg/mL. No correlation was observed between NfL levels and age, sex, or history of central nervous system involvement of the underlying malignancy. In summary, we found serum NfL levels are a robust, early marker for the development of ICANS. Our findings suggest the risk of developing ICANS reflects pre-transfusion host-factors, permitting the screening well in advance of drug administration.

Association between cerebrospinal fluid biomarkers of neuronal injury or amyloidosis and cognitive decline after major surgery

BackgroundPostoperative neurocognitive decline is a frequent complication in adult patients undergoing major surgery with increased risk for morbidity and mortality. The mechanisms behind cognitive decline after anaesthesia and surgery are not known. We studied the association between CSF and blood biomarkers of neuronal injury or brain amyloidosis and long-term changes in neurocognitive function. MethodsIn patients undergoing major orthopaedic surgery (knee or hip replacement), blood and CSF samples were obtained before surgery and then at 4, 8, 24, 32, and 48 h after skin incision through an indwelling spinal catheter. CSF and blood concentrations of total tau (T-tau), neurofilament light, neurone-specific enolase and amyloid β (Aβ1-42) were measured. Neurocognitive function was assessed using the International Study of Postoperative Cognitive Dysfunction (ISPOCD) test battery 1–2 weeks before surgery, at discharge from the hospital (2–5 days after surgery), and at 3 months after surgery. ResultsCSF and blood concentrations of T-tau, neurone-specific enolase, and Aβ1-42 increased after surgery. A similar increase in serum neurofilament light was seen with no overall changes in CSF concentrations. There were no differences between patients having a poor or good late postoperative neurocognitive outcome with respect to these biomarkers of neuronal injury and Aβ1-42. ConclusionsThe findings of the present explorative study showed that major orthopaedic surgery causes a release of CSF markers of neural injury and brain amyloidosis, suggesting neuronal damage or stress. We were unable to detect an association between the magnitude of biomarker changes and long-term postoperative neurocognitive dysfunction.

Nav1.6 promotes inflammation and neuronal degeneration in a mouse model of multiple sclerosis

BackgroundIn multiple sclerosis (MS) and in the experimental autoimmune encephalomyelitis (EAE) model of MS, the Nav1.6 voltage-gated sodium (Nav) channel isoform has been implicated as a primary contributor to axonal degeneration. Following demyelination Nav1.6, which is normally co-localized with the Na+/Ca2+ exchanger (NCX) at the nodes of Ranvier, associates with β-APP, a marker of neural injury. The persistent influx of sodium through Nav1.6 is believed to reverse the function of NCX, resulting in an increased influx of damaging Ca2+ ions. However, direct evidence for the role of Nav1.6 in axonal degeneration is lacking.MethodsIn mice floxed for Scn8a, the gene that encodes the α subunit of Nav1.6, subjected to EAE we examined the effect of eliminating Nav1.6 from retinal ganglion cells (RGC) in one eye using an AAV vector harboring Cre and GFP, while using the contralateral either injected with AAV vector harboring GFP alone or non-targeted eye as control.ResultsIn retinas, the expression of Rbpms, a marker for retinal ganglion cells, was found to be inversely correlated to the expression of Scn8a. Furthermore, the gene expression of the pro-inflammatory cytokines Il6 (IL-6) and Ifng (IFN-γ), and of the reactive gliosis marker Gfap (GFAP) were found to be reduced in targeted retinas. Optic nerves from targeted eyes were shown to have reduced macrophage infiltration and improved axonal health.ConclusionTaken together, our results are consistent with Nav1.6 promoting inflammation and contributing to axonal degeneration following demyelination.

Western diet‐induced insulin resistance impairs recovery after experimental spinal cord injury

The cardinal signs of systemic metabolic dysfunction, including insulin resistance, hypertension and a systemic pro‐inflammatory state are risk factors for the development of cardiovascular disease, type 2 diabetes, and neurodegenerative conditions, but there is limited information regarding the impact on recovery after spinal cord injury (SCI). To address this gap, we investigated the impact of systemic insulin resistance generated by consumption of a diet high in fat and sucrose, often referred to as a Western Diet, on neuropathophysiological outcomes in a murine compression model of incomplete SCI. Ten‐week‐old female C57BL6 mice were provided a regular diet (RD) or a diet high in fat and sucrose (HFHS) for 7 weeks prior to experimental compression SCI.Mice consuming a Western Diet showed signs of systemic insulin resistance such as evaluated blood glucose. In addition, signs of insulin resistance within the substance of the spinal cord were also observed, including reductions in the abundance of insulin‐like growth factor 1 receptor (IGF‐1R). Impairments in motor recovery evaluated by BMS score and subscore were present in mice consuming HFHS at 14 and 30 days post injury (dpi). Consumption of a diet rich in fat and sucrose also impaired the mean maximal angle achieved on the inclined plane test and resulted in significant impairments in bladder release. Immunochemical analysis of the spinal cord revealed a number of differences in markers of neural injury between the two groups. First, mice consuming HFHS exhibited significant increases in astrogliosis measured by glial fibrillary acidic protein (GFAP) prior to injury, compared to mice consuming a RD. In fact, the prominent increases in GFAP observed in the intact spinal cord of mice consuming HFHS were equivalent to those observed after SCI in mice consuming a regular chow. In the subacute period, markers of microglial/monocyte activation were elevated in all mice with SCI; however, the increase was substantially greater in the spinal cords of mice consuming HFHS. The spinal cord white matter of mice consuming HFHS also showed reductions in the number of oligodendrocyte progenitor and mature myelinating cells prior to SCI and HFHS‐associated reductions in myelin producing cells persisted at 14 and 30 dpi. In addition, loss of serotonergic axons in the spinal cord after SCI was exacerbated in mice consuming HFHS. Growth associated protein 43 (GAP43), a marker of axonal growth cones was elevated after SCI in the spinal cords of mice consuming a RD or a HFHS diet; however, the magnitude of the increase in growth cones was severely impaired in mice consuming HFHS.These findings suggest that consumption of a Western Diet increases the risk of insulin resistance within the central nervous system and impairs neurobehavioral recovery after SCI. These studies highlight insulin resistance as a new mechanism that limits nervous system repair after SCI and as a potential target for intervention to improve functional outcomes.Support or Funding InformationNIH R01 NS052741 and The Minnesota State SCI and TBI Research Grant Program.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Every hit matters: White matter diffusivity changes in high school football athletes are correlated with repetitive head acceleration event exposure.

Recent evidence of short-term alterations in brain physiology associated with repeated exposure to moderate intensity subconcussive head acceleration events (HAEs), prompts the question whether these alterations represent an underlying neural injury. A retrospective analysis combining counts of experienced HAEs and longitudinal diffusion-weighted imaging explored whether greater exposure to incident mechanical forces was associated with traditional diffusion-based measures of neural injury—reduced fractional anisotropy (FA) and increased mean diffusivity (MD). Brains of high school athletes (N = 61) participating in American football exhibited greater spatial extents (or volumes) experiencing substantial changes (increases and decreases) in both FA and MD than brains of peers who do not participate in collision-based sports (N = 15). Further, the spatial extents of the football athlete brain exhibiting traditional diffusion-based markers of neural injury were found to be significantly correlated with the cumulative exposure to HAEs having peak translational acceleration exceeding 20 g. This finding demonstrates that subconcussive HAEs induce low-level neurotrauma, with prolonged exposure producing greater accumulation of neural damage. The duration and extent of recovery associated with periods in which athletes do not experience subconcussive HAEs now represents a priority for future study, such that appropriate participation and training schedules may be developed to minimize the risk of long-term neurological dysfunction.

Integration of Biomarkers Into a Signature Profile of Persistent Traumatic Brain Injury Involving Autoimmune Processes Following Water Hammer Injury From Repetitive Head Impacts.

Objectives:To assemble an algorithm that will describe a “Signature” predictive of an individual’s vulnerability to persistent traumatic brain injury (TBI)Subjects and Methods:Studies of athletes and warriors who are subjected to repeated head impacts with rapid acceleration/deceleration forces are used to assist in the diagnosis and management of TBI-affected individuals. Data from multiple areas, including clinical, anatomical, magnetic resonance imaging, cognitive function, and biochemical analyses, are integrated to provide a Signature of persistent TBI.Results:Studies to date indicate that susceptibility to TBI results from an interaction between host genetic and structural vulnerability factors and force and torque of impact on the head and torso. The host factors include molecular markers affecting immune and inflammatory responses to stress/insult as well as anatomical features such as the degree of transcortical fiber projections and vascular malformations. The host response to forceful impact includes the release of intracellular neural proteins and nucleic acids into the cerebrospinal fluid and vascular compartment as well as mobilization of cytokines and macrophages into the central nervous system with subsequent activation of microglia and inflammatory responses including autoimmune processes. Maximum impact to the base of the sulci via a “water hammer effect” is consistent with the localization of microvascular and inflammatory responses in the affected brain region.Conclusions:An assessment of an individuals’ predisposition to persistent TBI with delayed cognitive deficits and behavioral changes requires an understanding of host vulnerability (genetic factors and brain structure) and external stressors (force and torque of impact as well as repetitive head injury and time interval between impacts). An algorithm that has utility in predicting vulnerability to TBI will include qualitative and quantitative measures of the host factors weighted against post impact markers of neural injury. Implementation of the resulting “Signature” of vulnerability at early stages of injury will help inform athletes and warriors, along with commanders and management, of the risk/benefit approaches that will markedly diminish health care costs to the nation and suffering to this population. This report attempts to define a strategy to create such an algorithm.

Nerve and skin damage in leprosy is associated with increased intralesional heat shock protein.

Leprosy is frequently complicated by the development of reversal reactions in which peripheral nerve and skin lesions become inflamed and irreversible nerve damage may ensue. Increased expression of proteins belonging to the 70-kD heat shock family (hsp 70) occurs in cells of the central nervous system exposed to hyperthermia, physical damage or drug-induced trauma. In the present study we have used immunocytochemical staining to monitor hsp70 levels in peripheral nerves infected by Mycobacterium leprae. Hsp70 was detected in skin and nerve lesions from all leprosy patients, but was particularly prominent in lesions from patients undergoing reversal reactions. Hsp70 immunocytochemistry can thus be used as a marker of neural injury in the peripheral as well as in the central nervous system. The cellular dynamics of nerve damage in leprosy are currently poorly understood, and we postulate that the immunopathology of leprosy may be partly due to an autoimmune response to heat shock proteins.

MAP2 provides reliable early assessment of neural injury in the newborn piglet model of birth asphyxia

Reduction in microtubule-associated-protein-2 (MAP2) immunoreactivity is a sensitive and quantifiable early marker of neural injury in rats. This study assessed the reliability of MAP2 as an early marker of neural injury following hypoxia/ischaemia in neonatal piglets, and compared the effects of perfusion and immersion fixation on MAP2 immunoreactivity. Hypoxia was induced in newborn piglets ( n = 23) by reducing the FiO 2 to 4% for 0, 25, 35 or 50 min. Six hours after the end of hypoxia piglets were killed, and the brain removed and immunolabelled for MAP2. Significant reductions in MAP2 immunoreactivity were seen in cortex, hippocampus, basal ganglia and thalamus. Reductions correlated with duration of hypoxia, pH at the end of hypoxia, cerebral function monitor amplitude and cerebral impedance 6 h after hypoxia, and with early histological evidence of ischaemic changes. Regions with reduced immunoreactivity correlated with areas where damage is present in later histological examination in this model. Immersion fixation with postmortem delays up to 30 min did not affect MAP2 immunoreactivity compared to perfusion-fixed tissue. Results indicate that MAP2 immunoreactivity 6 h after hypoxia/ischaemia is a reliable marker of neural injury in the neonatal piglet.

Normalisation of cerebrospinal fluid biomarkers parallels improvement of neurological symptoms following HAART in HIV dementia – case report

BackgroundSince the introduction of HAART the incidence of HIV dementia has declined and HAART seems to improve neurocognitive function in patients with HIV dementia. Currently, HIV dementia develops mainly in patients without effective treatment, though it has also been described in patients on HAART and milder HIV-associated neuropsychological impairment is still frequent among HIV-1 infected patients regardless of HAART. Elevated cerebrospinal fluid (CSF) levels of markers of neural injury and immune activation have been found in HIV dementia, but neither of those, nor CSF HIV-1 RNA levels have been proven useful as diagnostic or prognostic pseudomarkers in HIV dementia.Case presentationWe report a case of HIV dementia (MSK stage 3) in a 57 year old antiretroviral naïve man who was introduced on zidovudine, lamivudine and ritonavir boosted indinavir, and followed with consecutive lumbar punctures before and after two and 15 months after initiation of HAART. Improvement of neurocognitive function was paralleled by normalisation of CSF neural markers (NFL, Tau and GFAP) levels and a decline in CSF and serum neopterin and CSF and plasma HIV-1 RNA levels.ConclusionThe value of these CSF markers as prognostic pseudomarkers of the effect of HAART on neurocognitive impairment in HIV dementia ought to be evaluated in longitudinal studies.

Cortical and subcortical neurodegeneration is associated with HIV neurocognitive impairment

To determine the association of markers of regional neurodegeneration (ND) at autopsy to degree of neurocognitive impairment in persons with HIV. In a prospectively followed cohort of HIV-infected individuals we examined the relationship between antemortem neuropsychological (NP) abilities and postmortem neuropathological data. Twenty-seven HIV-infected individuals with both neuropsychological and neuropathological data were identified. Laser confocal scanning microscopy was used to determine the degree of ND based on: (1) microtubule-associated protein (MAP2; reflecting neuronal cell bodies and dendrites) and (2) synaptophysin (SYN; a measure of presynaptic terminals). A regional combined score, based on the distribution of percentage neuropil occupied by MAP2 and SYN and emphasizing severity of ND, was created for each brain region: midfrontal cortex, hippocampus, and putamen. The regional combined scores from each brain region studied were better correlated with level of global NP impairment than measures of SYN and MAP2 individually. In a regression, hippocampal and putamen regional combined scores were independent predictors of degree of antemortem NP impairment (F(3,23) = 6.17; P < 0.01; R2 = 0.45). The correlations among regional ND measures demonstrated that ND is unevenly distributed across multiple brain regions. As the anatomic distribution and temporal progression of neuropathologic changes appears to differ across individuals, it is important to consider both cortical and subcortical brain regions in studies of neuropathogenesis and treatment of HIV-related brain disease. Furthermore, combining information from several markers of neural injury provided the strongest association with degree of neurocognitive impairment during life.

Serum S100B in pregnancy-related hypertensive disorders: a case-control study.

Eclampsia is defined as the occurrence of seizures and/or coma resulting from hypertensive encephalopathy on a background of preeclampsia (1). Eclampsia appears to be caused by a failure of the brain’s autoregulatory response to increases in blood pressure, leading to an increase in cerebral perfusion pressure with overperfusion injury similar to that observed in hypertensive encephalopathy (2)(3). Brain edema and hemorrhage ensue, as observed in imaging studies (4)(5), and there is evidence to suggest that these alterations can cause ischemia to brain cells. These events lead to neurologic symptoms (6), including seizures as well as cortical blindness, aphasia, limb weakness, psychosis, coma, and cerebrovascular accidents. Studies have analyzed various diagnostic methods, such as transcranial Doppler measurements, as a way to evaluate neurologic involvement in preeclampsia (3)(7). To date, however, there is no reliable laboratory marker to identify patients at risk for eclampsia or its related complications. S100B is a 21-kDa protein physiologically produced and released primarily by astrocytes in the central nervous system (CNS), where it exerts neurotrophic and gliotrophic actions (8). Because ∼95% of S100B is located in the CNS, the results of several studies have suggested that an increase in S100B in blood and cerebrospinal fluid could be a potential marker of neural injury, indicating reactive gliosis, astrocytic death, and/or blood–brain barrier dysfunction. Accordingly, increased S100B concentrations in cerebrospinal fluid and/or blood have been reported in several pathologic conditions causing acute and chronic brain injury, such as head trauma (9), stroke (10), schizophrenia (11), and human T-lymphotropic virus type 1-associated myelopathy (12). Some studies have also evaluated S100B as a marker of recent seizures. Although S100B has been shown to be increased in both cerebrospinal fluid and brain tissue of patients with temporal lobe epilepsy (13)(14), studies in which …

The Serum S100B Concentration Is Age Dependent

S100B is a 21-kDa calcium-binding protein produced and released primarily by astrocytes in the central nervous system (CNS), where it exerts neurotropic and gliotropic actions (1). Several studies have investigated the potential role of S100B as a peripheral biochemical marker of neural injury, including reactive gliosis, astrocytic death, and/or blood-brain barrier dysfunction (2). Increased cerebrospinal fluid (CSF) and/or serum S100B has been reported in several acute and chronic injuries, including traumatic brain injury (3), stroke (4), Alzheimer disease (5), schizophrenia (6), HTLV-I-associated myelopathy (7), and systemic lupus erythematosus (8). Previous neurodevelopmental studies have demonstrated age-related changes in S100B tissue expression and distribution in the CNS in mammals, which may be related to the different roles of this protein in distinct brain regions during the fetal period, adulthood, and aging (1)(9). Furthermore, S100B concentrations in CSF have been noted to increase with age in healthy individuals (10). Because these increases are more evident in men than women (11), S100B concentrations in CSF may be sex and age dependent, suggesting that age- and sex-matched controls may be necessary for studies of S100B in CSF. To determine the usual concentrations for plasma S100B in adults, Wiesmann et al. (12) measured the protein in healthy blood donors and found no differences with sex and age in individuals 18–65 years of age, in agreement with our findings in previous studies in adults (6)(7)(8). To our knowledge, however, S100B concentrations in blood in childhood and adolescence were not established until recently. The present study was performed to verify S100B serum concentrations in healthy individuals of different ages, ranging from neonates to adults. We collected blood samples from 19 healthy term neonates (<48 h of age) and from 25 healthy children 4–16 years of age undergoing routine clinical and …

Laminin-like and laminin-binding protein-like immunoreactive astrocytes in rat hippocampus after transient ischemia. Antibody to laminin-binding protein is a sensitive marker of neural injury and degeneration.

Laminin-like and laminin-binding protein-like immunoreactive astrocytes in rat hippocampus after transient ischemia. Antibody to laminin-binding protein is a sensitive marker of neural injury and degeneration.

Heat shock proteins as markers of neural injury

Systemic or intracerebral injections of kainic acid induced immunoreactivity for the 72 kDa heat shock protein (HSP72) in individual neurons of the rat brain in patterns matching the known histopathology of the particular injury. HSP72 immunostaining was also induced in and around areas of infarction following experimental strokes. These results suggest that HSP72 immunocytochemistry may be used as a marker of cellular injury in the mammalian brain.