Motoki Fujita

Serum Glial Fibrillary Acidic Protein Is a Highly Specific Biomarker for Traumatic Brain Injury in Humans Compared With S-100B and Neuron-Specific Enolase

BACKGROUND Serum glial fibrillary acidic protein (GFAP) is a specific predictor of brain damage and neurologic outcome in patients with traumatic brain injury (TBI). In this study, serum GFAP, S-100B, and neuron-specific enolase (NSE) were compared in the same samples from severe trauma patients to assess their ability to predict abnormalities detectable on head computed tomography (CT). METHODS This study was a retrospective analysis at a single university emergency center. Thirty-four trauma patients were included. Serum samples were collected from the patients for 3 days. Serum GFAP, S-100B, and NSE concentrations were measured with enzyme-linked immunosorbent assays and compared in patients with and without TBI, as evaluated by head CT. RESULTS Serum GFAP, S-100B, and NSE were significantly higher in the TBI patients than in the non-TBI patients (p < 0.05 for each protein). The receiver operating characteristic curves for TBI were compared for the three biomarkers for 3 days. Serum GFAP on day 1 had the largest area under the receiver operating characteristic curve (0.983), with 88.9% sensitivity and 100% specificity. CONCLUSIONS Serum GFAP has remarkable diagnostic value for TBI, defined by abnormal head CT findings, in prehospital-triaged patients with severe trauma.

Serum glial fibrillary acidic protein as a predictive biomarker of neurological outcome after cardiac arrest

AIM OF THE STUDY Serum glial fibrillary acidic protein (GFAP) has recently been identified as a specific predictor of brain damage and neurological outcome in patients with head trauma. In this study, serum GFAP was assessed as a predictor of neurological outcome in post-cardiac-arrest (PCA) patients. METHODS This study was a retrospective, single-medical-center analysis, conducted in the intensive care unit of a university hospital. Forty-four sequential PCA patients with cardiogenic or non-cardiogenic arrest were included. The patients were treated with or without therapeutic hypothermia (TH). Serum samples were collected from the patients at 12, 24, and 48h after the return of spontaneous circulation (ROSC). Serum GFAP concentrations were measured by enzyme-linked immunosorbent assay and compared in patients with good and poor neurological outcomes, evaluated over a period of 6 months using Glasgow Outcome Scale. RESULTS Serum GFAP was significantly higher in patients with a poor outcome at 12 and 24h without TH and at 48h with TH (P<0.05). GFAP (>0.1ngdL(-1)) was a specific predictor of poor neurological outcome at 6 months with or without TH treatment. CONCLUSIONS Although this study is preliminary, serum GFAP after ROSC reflected a poor neurological outcome in PCA patients.

Hyperglycemia enhances excessive superoxide anion radical generation, oxidative stress, early inflammation, and endothelial injury in forebrain ischemia/reperfusion rats

The aim of this study was to confirm the effect of acute hyperglycemia on the superoxide anion radical (O(2)(-)) generation, using a novel electrochemical O(2)(-) sensor in forebrain ischemia/reperfusion rats. Fourteen male Wistar rats were allocated to a normoglycemia group (n= 7) and a hyperglycemia group (n=7). Hyperglycemia was induced by intravenous infusion of glucose solution. Forebrain ischemia was induced by bilateral common carotid arteries occlusion with hemorrhagic hypotension for 10 min and then was reperfused. The generated O(2)(-) was measured as the current produced, which was integrated as a quantified partial value of electricity (Q), in the jugular vein using the O(2)(-) sensor. The reacted O(2)(-) current and the Q began to increase gradually during the forebrain ischemia in both groups. These values increased remarkably just after reperfusion in the normoglycemia group and were further increased significantly in the hyperglycemia group after the reperfusion. Concentrations of malondialdehyde (MDA) and high-mobility group box 1 (HMGB1) in the brain and plasma, and soluble intercellular adhesion molecule-1 (ICAM-1) in the plasma in the hyperglycemia group were significantly higher than those in the normoglycemia group. Brain and plasma MDA, HMGB1, and ICAM-1 were correlated with a sum of Q during ischemia and after reperfusion. In conclusion, acute transient hyperglycemia enhanced the O(2)(-) generation in blood and exacerbated oxidative stress, early inflammation, and endothelial injury after the forebrain ischemia/reperfusion in the rats.

Intensity- and Interval-Specific Repetitive Traumatic Brain Injury Can Evoke Both Axonal and Microvascular Damage

In the experimental setting several investigators have recently reported exacerbations of the burden of axonal damage and other neuropathological changes following repetitive traumatic brain injuries (TBI) that were sustained at intervals from hours to days following the initial insult. These same studies also revealed that prolonging the interval between the first and second insult led to a reduction in the burden of neuropathological changes and/or their complete elimination. Although demonstrating the capability of repetitive TBI to evoke increased axonal and other neuropathological changes, these studies did not address the potential for concomitant microvascular dysfunction or damage, although vascular dysfunction has been implicated in the second-impact syndrome. In this study we revisit the issue of repetitive injury in a well-controlled animal model in which the TBI intensity was bracketed from subthreshold to threshold insults, while the duration of the intervals between the injuries varied. Employing cranial windows to assess vascular reactivity and post-mortem amyloid precursor protein (APP) analysis to determine the burden of axonal change, we recognized that subthreshold injuries, even when administered in repeated fashion over a short time frame, evoked neither axonal nor vascular change. However, with an elevation of insult intensity, repetitive injuries administered within 3-h time frames caused dramatic axonal damage and significant vascular dysfunction bordering on a complete loss of vasoreactivity. If, however, the interval between the repetitive injury was extended to 5 h, the burden of axonal change was reduced, as was the overall magnitude of the ensuing vascular dysfunction. With the extension of the interval between injuries to 10 h, neither axonal nor vascular changes were found. Collectively, these studies reaffirm the existence of significant axonal damage following repetitive TBI administered within a relatively short time frame. Additionally, they also demonstrate that these axonal changes parallel changes in the cerebral microcirculation, which also may have adverse consequences for the injured brain.

Xanthine oxidase is one of the major sources of superoxide anion radicals in blood after reperfusion in rats with forebrain ischemia/reperfusion

We recently reported that excessive superoxide anion radical (O(2)(-)) was generated in the jugular vein during reperfusion in rats with forebrain ischemia/reperfusion using a novel electrochemical sensor and excessive O(2)(-) generation was associated with oxidative stress, early inflammation, and endothelial injury. However, the source of O(2)(-) was still unclear. Therefore, we used allopurinol, a potent inhibitor of xanthine oxidase (XO), to clarify the source of O(2)(-) generated in rats with forebrain ischemia/reperfusion. The increased O(2)(-) current and the quantified partial value of electricity (Q), which was calculated by the integration of the current, were significantly attenuated after reperfusion by pretreatment with allopurinol. Malondialdehyde (MDA) in the brain and plasma, high-mobility group box 1 (HMGB1) in plasma, and intercellular adhesion molecule-1 (ICAM-1) in the brain and plasma were significantly attenuated in rats pretreated with allopurinol with dose-dependency in comparison to those in control rats. There were significant correlations between total Q and MDA, HMGB, or ICAM-1 in the brain and plasma. Allopurinol pretreatment suppressed O(2)(-) generation in the brain-perfused blood in the jugular vein, and oxidative stress, early inflammation, and endothelial injury in the acute phase of forebrain ischemia/reperfusion. Thus, XO is one of the major sources of O(2)(-)- in blood after reperfusion in rats with forebrain ischemia/reperfusion.

Urinary trypsin inhibitor suppresses excessive superoxide anion radical generation in blood, oxidative stress, early inflammation, and endothelial injury in forebrain ischemia/reperfusion rats.

Abstract Objectives: To investigate the effects of ulinastatin, a urinary trypsin inhibitor (UTI), on jugular venous superoxide radical (O−2·) generation, oxidative stress, early inflammation, and endothelial activation in forebrain ischemia/reperfusion (FBI/R) rats.Methods: Fourteen Wistar rats were allocated to a control group (n = 7) and a UTI group (n = 7). Throughout the experiments, O−2· in the jugular vein was measured by the produced current using a novel electrochemical O−2· sensor. Forebrain ischemia was induced by occlusion of the bilateral common caroti darteries with hemorrhagic hypotension for 20 min, followed by reperfusion. In the UTI group, UTI (5 U/g) was administered intravenously immediately after reperfusion. At 60 min after reperfusion, plasma and brain were harvested, and malondialdehyde, high-mobility group box 1 (HMGB1) protein, and intercellular adhesion molecule-1 (ICAM-1) were measured. Results: O−2· current increased gradually during forebrain ischemia in both groups. The current increased markedly in the control group immediately after reperfusion but was significantly attenuated in the UTI group after reperfusion. Brain and plasma malondialdehyde, HMGB1, and ICAM-1 were significantly attenuated in the UTI group compared with those in the control group, except for brain HMGB1, which was associated with the amount of O−2· generated during FBI/R. Discussion: UTI suppressed jugular venous O−2· generation, oxidative stress, early inflammation, and endothelial activation in FBI/R rats. Therefore, UTI might be a useful agent for the therapy of the cerebral ischemia/reperfusion pathophysiology.

In vivo real-time measurement of superoxide anion radical with a novel electrochemical sensor

The dynamics of superoxide anion (O(2)(-)) in vivo remain to be clarified because no appropriate method exists to directly and continuously monitor and evaluate O(2)(-) in vivo. Here, we establish an in vivo method using a novel electrochemical O(2)(-) sensor. O(2)(-) generated is measured as a current and evaluated as a quantified partial value of electricity (Q(part)), which is calculated by integration of the difference between the baseline and the actual reacted current. The accuracy and efficacy of this method were confirmed by dose-dependent O(2)(-) generation in xanthine-xanthine oxidase in vitro in phosphate-buffered saline and human blood. It was then applied to endotoxemic rats in vivo. O(2)(-) current began to increase 1 h after lipopolysaccharide, and Q(part) increased significantly for 6 h in endotoxemic rats, in comparison to sham-treated rats. These values were attenuated by superoxide dismutase. The generation and attenuation of O(2)(-) were indirectly confirmed by plasma lipid peroxidation with malondialdehyde, endothelial injury with soluble intercellular adhesion molecule-1, and microcirculatory dysfunction. This is a novel method for measuring O(2)(-) in vivo and could be used to monitor and treat the pathophysiology caused by excessive O(2)(-) generation in animals and humans.

Early induction of moderate hypothermia suppresses systemic inflammatory cytokines and intracellular adhesion molecule-1 in rats with caerulein-induced pancreatitis and endotoxemia

Objectives: To evaluate the systemic effects of moderate hypothermia (MH) and the timing of induction on acute pancreatitis (AP) and endotoxemia in rats. Methods: The effects of MH were compared in 4 groups, that is, sham group (38°C), control group (38°C), early MH group (32°C on administration of lipopolysaccharide [LPS]), and delayed MH group (32°C 1 hour after LPS). AP and endotoxemia were induced by intramuscular injection of caerulein and intraperitoneal injection of LPS. Results: Serum interleukin 6 (IL-6) in both MH groups was significantly lower than that in the control group at 3 hours. Serum interleukin 10 (IL-10) in the early MH group was significantly higher than those in the other 3 groups at 1 hour. IL-10/IL-6 ratios in both MH groups were significantly higher than that in the control group at 3 hours. Serum soluble intercellular adhesion molecule (sICAM-1) in both MH groups was significantly lower than that in the control group at 3 hours. Serum sICAM-1 in the early MH group was significantly lower than that in the delayed MH group. The tendency of pancreatic ICAM-1 was similar to that of serum sICAM-1. Conclusions: Early induction of MH might be protective against pancreatic injury and systemic inflammation in AP and endotoxemia.

Prognostic value of biochemical markers of brain damage and oxidative stress in post-surgical aneurysmal subarachnoid hemorrhage patients

The aim of this study is to determine effective biochemical markers and optimal sampling timing for prediction of neurological prognosis in post-surgical aneurysmal subarachnoid hemorrhage (SAH) patients. Subjects were a sequential group of SAH patients admitted to our centre who underwent aneurysm clipping before Day 3 and who received a cerebrospinal fluid (CSF) drain. CSF samples from 32 patients were collected on Days 3, 7, and 14. Neurological outcome was assessed by neurosurgeons using the Glasgow outcome scale (GOS) at 6 months after onset. CSF levels of neuron-specific enolase (NSE), S100B, and glial fibrillary acidic protein (GFAP) were determined using enzyme-linked immunosorbent assay, and the CSF concentrations of malondialdehyde (MDA) were determined using spectrophotometric assay. In univariate analysis, S100B on Days 3 and 14, GFAP on Days 3 and 7, and MDA on Day 14 were significantly higher in the poor outcome group (GOS 1-4) than in the good outcome group (GOS 5). In multivariate analysis, only MDA on Day 14 was identified as a significant predictor of poor neurological outcome at 6 months after onset. The area under the receiver-operating characteristic (ROC) curve for MDA on Day 14 was 0.841. For a threshold of 0.3 microM, sensitivity and specificity were 0.875 and 0.750, respectively. Our findings suggest that these biochemical markers, especially MDA, show significant promise as predictors of neurological outcome in clinical practice.

Prediction of the neurological outcome with intrathecal high mobility group box 1 and S100B in cardiac arrest victims: A pilot study

OBJECTIVES To investigate whether high mobility group box 1 (HMGB1) and S100B in cerebrospinal fluid (CSF) and the serum predict the neurological outcome in patients resuscitated from out-of-hospital cardiac arrest (OHCA). MATERIALS AND METHODS This study was designed as a prospective observational study. Twenty-five patients, who received standard cardiopulmonary resuscitation and post-resuscitation intensive care, were enrolled in this study. The patients were divided into two groups according to Glasgow-Pittsburgh Cerebral Performance categories (CPCs) at 6 months after return of spontaneous circulation (ROSC), Group G (n = 7, CPC 1 or 2) and Group P (n = 18, CPC ≥ 3). Their blood samples were taken at 6, 24, and 48h after ROSC. The patients, whose CSF was sampled at 48h, were also divided into either sub-Group G (n = 6) or sub-Group P (n = 8) at 6 months after ROSC. RESULTS HMGB1 and S100B in CSF in sub-Group P were significantly higher than those in sub-Group G (HMGB1, <1.0 vs. 12.4 ng/ml, P = 0.009; S100B, 2.68 vs. 84.2 ng/ml, P = 0.007, respectively). HMGB1 in CSF was strongly correlated with S100B (σ = 0.81, P = 0.001). HMGB1 was elevated in serum at 6h and normalized within 48 h after ROSC without any significant differences between the two groups. Serum S100B in Group P was significantly higher than that in Group G at each time point. CONCLUSIONS The significant elevations of HMGB1 and S100B in CSF, and S100B in serum are associated with the neurologically poor outcome in OHCA patients.