Changes in concentration of cerebrospinal fluid components in patients with traumatic brain injury

Brain injury, like other central nervous system pathologies, causes changes in the composition of the cerebrospinal fluid (CSF). In this study, changes in the concentration of small molecules of the CSF, which are in the minimal micromolar concentration, were observed and monitored using high-resolution proton (NMR) spectroscopy. Twenty-two patients with isolated traumatic brain injuries (TBI) and 15 patients making up the control group were recruited for the study. CSF samples were collected by lumbar puncture from the lumbar subarachnoid space in the patients just before commencement of therapy and on the first, third, seventh and fourteenth days of therapy at the ICU. Forty-four signals of the NMR spectra and NO concentration of the CSF samples were analyzed. The analysis shows that the amino acid and organic acid concentrations change during the therapy and mostly are higher than in the control group. Significant differences in concentration of the analyzed CSF components between the TBI patients and the control group have been noted. The rate of the lactate to pyruvate conversion increased because the L/P ratio showed no significant differences between the TBI group and the control group, while the concentrations of both components were significantly higher in the TBI patients than in the control group. Citrulline, arginine and nitric oxide concentrations were the focus of the analysis. Citrulline concentration changes overlapped NO changes from 0 until 3rd day of therapy, while for the remaining days of observation the NO concentration stabilized at the control level, whereas citrulline concentration significantly decreased.     

急性颅脑损伤后脑脊液抑制性氨基酸的变化及意义

目的探讨脑脊液中抑制性氨基酸的水平与颅脑损伤严重程度的关系。方法将71例急性颅脑损伤患者按入院时GCS评分分为9~15分组（37例）和3~8分组（34例）,伤后1、3、7 d采集脑脊液标本;以28例正常脑脊液标本作对照组。采用柱前衍生反相高效液相色谱紫外吸收检测法定量分析脑脊液标本中γ-氨基丁酸（GABA）、牛磺酸（Tau）和丙氨酸（Ala）浓度。结果颅脑损伤后脑脊液GABA、Tau浓度均高于对照组,GCS 3~8分组Tau浓度均明显高于GCS 9~15分组（P〈0.05）。颅脑损伤后1、7d,GCS 3~8分组GABA浓度高于GCS 9~15分组（P〈0.05）,伤后3 d时两组浓度无显著性差异（P〉0.05）。颅脑损伤后Ala浓度较对照组明显下降（P〈0.05）。结论脑脊液GABA、Tau在颅脑损伤后反应性增高提示其可能与颅脑损伤的严重程度相关。脑脊液Ala浓度在颅脑损伤后下降提示颅脑损伤后部分脑保护机制受到损害。     

Caspase-3 activity is present in cerebrospinal fluid from patients with traumatic brain injury.

Loss of neurons after traumatic brain injury (TBI) might involve dysregulated apoptosis. Activation of caspase-3 is one hallmark of apoptosis. Therefore, caspase-3 activity (cleavage of DEVD-afc) was measured in cerebrospinal fluid (CSF) samples (n=113) from 27 patients with TBI at day 1 to 14 after trauma. Caspase-3 activity was detected in 31 (27.4%) CSF samples with highest values (> 5.5 microM/min) seen at day 2-5 after trauma. No caspase-3 activity was found in serum from patients or CSF from controls. The presence of activated caspase-3 in CSF suggests ongoing apoptotic processes during traumatic brain injury.     

重型颅脑损伤患者脑脊液SBDPs的水平变化

目的探讨重型颅脑损伤患者脑脊液中αⅡ血影蛋白裂解产物（SBDPs,包括SBDP140和SBDP120）浓度与颅脑损伤的程度和患者预后的关系。方法选择40例重型颅脑损伤（Gcs≤8分）患者（颅脑损伤组）,伤后6h、12h、24h、1d、2d、3d、4d、5d．6d．7d取脑脊液采用酶联免疫吸附法检测SBDP140和SBDP120浓度;选择24例脑积水患者作为对照组。结果不同时间点颅脑损伤组脑脊液SBDP145和SBDP120浓度均明显高于对照组（P〈0.05）,SBDP145在伤后6h就达最高峰,而SBDP120直到到伤后5d才达峰值。不同时间点伤后3个月死亡的颅脑损伤患者脑脊液的SBDP145和SBDP120浓度明显高于生存的患者（p〈0．05）。入院时GCS评分6—8分患者脑脊液离脊液SBDP145的浓度明显低于入院时GCS评分3-5的患者（P〈0．05）,而SBDP120的浓度两者之间无明显变化（P〉0．05）。结论颅脑损伤患者脑脊液SBDPs与颅脑损伤的严重性和患者预后有关。     

Interleukin-6 released in human cerebrospinal fluid following traumatic brain injury may trigger nerve growth factor production in astrocytes

Cytokines are involved in nerve regeneration by modulating the synthesis of neurotrophic factors. The role played by interleukin-6 (IL-6) in promoting nerve growth factor (NGF) after brain injury was investigated by monitoring the release of IL-6 and NGF in ventricular cerebrospinal fluid (CSF) of 22 patients with severe traumatic brain injuries. IL-6 was found in the CSF of all individuals and remained elevated for the whole study period. NGF appeared in the CSF if IL-6 levels reached high concentrations and was often detected simultaneously with or following an IL-6 peak. The amounts of NGF correlated with the severity of the injury, as indicated by the clinical outcome of the patients. The functional relationship of IL-6 and NGF was investigated utilizing cultured mouse astrocytes. The CSF of 8 patients containing IL-6 induced NGF production in astrocytes, whereas control CSF without IL-6 had no effect. The induction of NGF was inhibited up to 100% by adding anti-IL-6 antibodies. These results were corroborated when astrocytes were exposed to recombinant IL-6 at different concentrations resulting in NGF production. Thus, the production of IL-6 within the injured brain may likely contribute to the release of neurotrophic factors by astrocytes.     

Ventricular cerebrospinal fluid hypocretin-I inversely correlates with glucose levels in cerebrospinal fluid and serum from patients with neurological injuries

Introduction: Hypocretin-1 is a hypothalamic neuropeptide that may help regulate arousal and feeding behavior and is quantifiable in cerebrospinal fluid (CSF). In this retrospective pilot study, hypocretin-1 levels obtained from ventricular CSF of neurologically injured patients were correlated with clinical and laboratory results to test whether arousal or metabolic factors might be related to the level of hypocretin-1. Methods: CSF samples from a heterogeneous group of neurosurgical patients with externally draining intraventricular catheters were assayed in a standard manner for hypocretin-1 and other routine laboratories. Associations were sought between hypocretin-1 and clinical data such as body mass index (BMI), temperature, and Glasgow Coma Scale (GCS) score and between hypocretin-1 and laboratory data such as serum and CSF glucose, protein, and cell counts. Results: Lower levels of ventricular CSF hypocretin-1 were correlated with higher levels of serum (p=0.020) and ventricular CSF glucose (p=0.001). Clinical findings such as BMI, temperature, and GCS failed to correlate with hypocretin-1. Conclusions: In a group of neurologically injured patients, hypocretin-1 and glucose levels are inversely correlated. More studies are needed to investigate these associations, particularly in a homogenous patient sample.     

Enzyme activity in the cerebrospinal fluid in patients with brain gliomas

The spinal fluid activities of aspartate aminotransferase (AAT), alkaline phosphatase (AP), and gamma-gluthamyl transferase were studied in 32 patients with cerebral gliomas to clarify the diagnostic role of these enzymes. There were different changes in their activities in groups of patients with low-differential and differential gliomas. Its was ascertained that higher AAT activity was due to the fact that blood had entered spinal fluid; increased AP activity may be regarded to be an indicator of higher permeability of the blood-brain barrier.     

急性颅脑损伤患者血清及脑脊液中炎性因子的变化及临床意义

目的探讨炎症细胞因子IL-1β,IL-6与颅脑损伤程度的关系及临床意义。方法对近年来我院收治的780例急性颅脑损伤患者按损伤程度分组（轻、中、重及特重型组）,检测血清及脑脊液中IL-1β及IL-6水平,并对比了不同程度急性颅脑损伤患者上述因子水平的差异并分析其临床意义。结果轻型、中型、重型及特重型颅脑损伤患者血清及脑脊液IL-1β及IL-6水平均显著增加,而重型和特重型颅脑损伤患者两种因子水平要显著高于其他患者,死亡患者IL-1β及IL-6水平高于其他所有患者。结论血清及脑脊液中IL-1β及IL-6水平与颅脑损伤的程度密切相关,能够作为临床监测指标。     

颅脑损伤后脑脊液C-反应蛋白与颅内压相关性及临床意义

目的探讨颅脑损伤后脑脊液C-反应蛋白(CRP)与颅内压变化的关系。方法颅脑损伤患者65例,按GCS评分分为轻型组15例,中型组20例,重型组30例。腰椎穿刺检测脑脊液压力,同时采集其伤后1 d内至4 w的脑脊液,以免疫比浊法测定脑脊液中CRP的含量,将脑脊液中CRP的含量与颅内压变化进行比较。结果伤后轻、中、重型各组脑脊液CRP与颅内压变化存在组间差异(P0.01);CRP含量的变化与颅内压变化呈正相关。结论脑脊液中CRP的含量是反映颅脑损伤急性期脑组织损伤的敏感指标,能反映颅脑损伤后颅内压变化趋势。     

37例培养阳性结核性脑膜脑炎脑脊液细胞学动态分析

目的探讨脑脊液结核分枝杆菌培养阳性结核性脑膜炎脑脊液细胞学特点。方法运用玻片细胞沉淀(粟秀初教授研制)细胞学方法,对37例使用Bactec MGIT 960培养阳性结核性脑膜炎患者的脑脊液细胞学分类特点进行动态观察与分析。结果结核性脑膜脑炎患者脑脊液白细胞总数升高,但有4例患者脑脊液白细胞数小于50×106/L。多数确诊结核性脑膜炎患者脑脊液呈混合型细胞反应,有33例(89.2%)患者脑脊液中检测到中性粒细胞,25例(67.6%)患者脑脊液中检测到浆细胞。但多数患者脑脊液(60%)以淋巴细胞为主,少量(1/3)以中性粒细胞为主。且几乎所有患者脑脊液内均可以检测到浆细胞的存在。结论确诊结核性脑膜炎患者的脑脊液白细胞数明显增高,脑脊液细胞分类主要表现为淋巴细胞为主型,少部分为中性粒细胞为主型。     

Endogenous melatonin increases in cerebrospinal fluid of patients after severe traumatic brain injury and correlates with oxidative stress and metabolic disarray

Oxidative stress plays a significant role in secondary damage after severe traumatic brain injury (TBI); and melatonin exhibits both direct and indirect antioxidant effects. Melatonin deficiency is deleterious in TBI animal models, and its administration confers neuroprotection, reducing cerebral oedema, and improving neurobehavioural outcome. This study aimed to measure the endogenous cerebrospinal fluid (CSF) and serum melatonin levels post-TBI in humans and to identify relationships with markers of oxidative stress via 8-isoprostaglandin-F2alpha (isoprostane), brain metabolism and neurologic outcome. Cerebrospinal fluid and serum samples of 39 TBI patients were assessed for melatonin, isoprostane, and various metabolites. Cerebrospinal fluid but not serum melatonin levels were markedly elevated (7.28+/-0.92 versus 1.47+/-0.35 pg/mL, P<0.0005). Isoprostane levels also increased in both CSF (127.62+/-16.85 versus 18.28+/-4.88 pg/mL, P<0.0005) and serum (562.46+/-50.78 versus 126.15+/-40.08 pg/mL (P<0.0005). A strong correlation between CSF melatonin and CSF isoprostane on day 1 after injury (r=0.563, P=0.002) suggests that melatonin production increases in conjunction with lipid peroxidation in TBI. Relationships between CSF melatonin and pyruvate (r=0.369, P=0.049) and glutamate (r=0.373, P=0.046) indicate that melatonin production increases with metabolic disarray. In conclusion, endogenous CSF melatonin levels increase after TBI, whereas serum levels do not. This elevation is likely to represent a response to oxidative stress and metabolic disarray, although further studies are required to elucidate these relationships.     

Increased cerebrospinal fluid glutamate and taurine concentrations are associated with traumatic brain edema formation in rats

Glutamate-mediated excitotoxicity results in cell swelling and contributes to brain edema formation. Since increased extracellular taurine reflects glutamate-induced cell swelling in vitro, elevated CSF taurine could therefore unmask glutamate-mediated cytotoxic edema formation under in vivo conditions. For this, the temporal profile of brain edema and changes in cisternal CSF glutamate and taurine levels were determined in 28 rats following focal traumatic brain injury. Compared to six non-traumatized rats, CSF glutamate (4. 8+/-0.3 vs. 10+/-0.9 microM) and taurine levels (12+/-1.3 vs. 41+/-3 microM) were significantly increased at 8 h after trauma (P<0.001). Over time, CSF glutamate and taurine were significantly increased by 24 (glutamate: 38+/-4.4 microM) and 48 h (taurine: 51+/-4 microM), respectively. While CSF glutamate closely reflected changes in hemispheric water content, alterations in CSF taurine occurred diametrically to those seen for glutamate. Under the present study design, increased CSF taurine could reflect glutamate-induced cell swelling. In addition, neuronal release of taurine with its inhibitory and antiexcitotoxic functions could explain the observed diametric changes in CSF glutamate, CSF taurine, and hemispheric water content. Therefore, increasing taurine could be a therapeutic approach in attenuating post-traumatic glutamate-mediated cell damage.     

Somatostatin concentrations in cerebrospinal fluid and brain tissue of patients with refractory epilepsy

The somatostatin concentrations of cerebrospinal fluid (CSF) and brain tissue in 16 refractory epileptic patients were measured simultaneously by a radioimmunoassay (RIA) method. An increased level of somatostatin was found in the epileptic foci of cerebral cortex, determined by the cortical EEG. There were significant differences among the epileptic foci (75.58±6.58 pg/mg wet wt, ±SEM), nonfocal tissues (37.04±6.55 pg/mg), and normal tissues of control patients (47.69±10.12 pg/mg),p<0.001 andp<0.05, respectively. The somatostatin concentrations of CSF in 11 epileptic patients were determined before (257.78±19.11 pg/mL) and after (178.36±8.78 pg/mL) the removal of epileptic focal area, and a dramatic decrease of the CSF somatostatin concentration after operation was detected (p<0.01). We also found that the somatostatin level of cerebral scar induced by head injury in cases of posttraumatic epilepsy was highest (106.39±12.41 pg/mg). The results suggested that the surgical removal of the epileptic focal area in refractory epileptic patients may reduce the increased central somatostatin level, which could play an important part in the pathophysiological process of refractory epilepsy.     

Treatment of traumatic acute subdural hematoma in adult hydrocephalus patients with cerebrospinal fluid shunt

Objective

The presence of a cerebrospinal fluid (CSF) shunt is a predisposing factor for the development of subdural hematoma (SDH) in patients with hydrocephalus. However, few reports have addressed how patients with a CSF shunt should be treated in the event of traumatic acute SDH. The purpose of this study was to show how post-traumatic management of CSF shunt affects acute SDH in adult patients with hydrocephalus.

Methods

Twelve patients were studied retrospectively. Pressure settings of shunt valve prior to head injury (HI), severity of HI, treatment on admission, changes in SDH thickness and subsequent hydrocephalus were mainly analyzed.

Results

Ten patients experienced mild HI, with nine showing neurological deterioration until admission. Five patients needed surgical hematoma removal soon after admission. SDH recurred in four cases where shunt pressure levels were kept relatively low. Shunt ligation or raising the pressure level in the programmable valve proved effective for controlling postoperative SDH in such cases. Six of the remaining seven patients underwent only shunt ligation or readjustment of pressure level in the programmable valve on admission. SDH thickness was reduced as ventricles dilated without major neurological complications. Four patients showed delayed development of SDH even though shunts were kept ligated.

Conclusions

Hematoma removal alone may result in hematoma recurrence and require a second treatment comprising shunt management to effectively control hematoma. Using shunt management as the only initial treatment can reduce hematoma volume, but some patients may suffer delayed SDH development and require surgery.     

Aquaporin-4-containing astrocytes sustain a temperature- and mercury-insensitive swelling in vitro

In order to understand the molecular mechanism underlying astroglial swelling, we studied primary astrocyte cultures from newborn mouse and analyzed them for expression of functional water channels. Immunocytochemical analysis of mouse brain confirms the presence of AQP4 location in astrocytic endfeet with a polarized pattern, as found in rat. Using Southern blot PCR and Western blot analysis, we demonstrate that primary astrocyte cultures from mouse express the AQP4 water channel at both the RNA and protein levels. Two polypeptides, of 30 kDa and 32 kDa, were identified in the astrocytes. Densitometric analysis demonstrates that the 32-kDa form represents 25% of the total AQP4 protein. Moreover, immunofluorescence experiments show strong surface membrane expression of AQP4 protein in cultured cells, even though the polarity of the expression is not maintained. Furthermore, functional studies indicate that cultured astrocytes manifest rapid and temperature-independent volume changes in response to osmotic gradients, in agreement with a channel-mediated water transport. Water movement was found to be HgCl(2) insensitive, suggesting AQP4 and AQP7 as putative water channels. Using Western blot and PCR experiments, we exclude the presence of AQP7 in astrocytes, indicating that only AQP4 is responsible for the rapid water movement. Altogether, the results indicate that primary astrocyte cultures are a valid cell model for further investigation of the molecular mechanism of water movement in the brain and its physiological regulation.