Serum and urine nitrate and nitrite are not reliable indicators of intrathecal nitric oxide production in acute brain injury

This study examined the correlation between nitric oxide (NO) metabolites in the three major body fluid compartments and assessed performance of newly described vanadium-based assay for simultaneous detection of nitrite and nitrate (NO(x)) in human samples. Vanadium reduces nitrate to nitrite, which can be measured after a colorimetric reaction with Griess reagents.Cisternal cerebro spinal fluid (CSF), serum and urine samples from 10 patients with acute brain injury (ABI) were compared to control subjects. Significantly higher CSF NO(x) levels were found in brain injury patients compared to control patients (19.7+/-13.7 vs. 6.5+/-2.3 microM; p=0.01), which persisted for 10-day period of observation. The serum and urine levels of NO(x) on admission were not statistically different (42.8+/-28.2 microM; 584.1+/-337.8 micromol/g Cr, respectively) from controls (36.8+/-14.8 microM; 819.7+/-356.0 micromol/g Cr), but tended to decrease during the disease course reaching the lowest level on day 6 (serum: 19.3+/-8.4 microM, urine: 300.4+/-111.9 micromol/g Cr). CSF levels of NO(x) correlated moderately with those in serum (p=0.001, R=0.5). Serum NO(x) concentrations correlated weakly with urine levels (p=0.04, R=0.3). There was no significant correlation between CSF NO(x) and urine NO(x) levels.In conclusion, patients suffering brain injury had increased NO(x) concentrations in CSF, which remained independent from other body fluid compartments. Serum and urinary NO(x) levels cannot be used as a reliable index to assess intrathecal NO production.     

Rho激酶、氧合血红蛋白与蛛网膜下腔出血后脑血管痉挛的关系

目的探讨Rho激酶、氧合血红蛋白在蛛网膜下腔出血后患者脑脊液中的表达与浓度及其在脑血管痉挛的调控作用。方法采集62例蛛网膜下腔出血患者入院后第1、3、7、10、14 d脑脊液标本,RT-PCR方法检测Rho激酶mRNA的表达,采用比色法测定脑脊液中氧合血红蛋白的浓度,采用TCD检测颅内主要动脉血流速度。结果出血后第3 d脑脊液中Rho激酶表达及氧合血红蛋白浓度增高,在出血后第7 d达到高峰,而后逐渐下降。结论蛛网膜下腔出血患者脑脊液中Rho激酶的表达与氧合血红蛋白浓度有关,参与蛛网膜下腔出血后脑血管痉挛的发生,其含量与脑血管痉挛程度相关。     

Cerebrospinal fluid sampling by lumbar puncture in rats - repeated measurements of nitric oxide metabolites

The ability to measure nitric oxide (NO) metabolites (NO2- plus NO3-: NOx) in cerebrospinal fluid (CSF) will facilitate understanding the involvement of NO in neurogenic or inflammatory diseases. The purposes of this study were to develop a reliable method for CSF sampling from the lumbar region, and to repeatedly measure NOx in naive rats. NOx in CSF were measured using the Griess method. Twelve young (13-week-old) and seven middle-aged (40-week-old) male Wistar rats were used. CSF (50-70 microl) was collected four times at 1-week intervals. The success rate of CSF collection was 96% and average surgery time was 21 min. The blood contamination rate was 11% on macroscopic inspection. NOx in the CSF ranged from 3.8 to 10.6 microM. The NOx in clear CSF were not significantly different from those with blood contamination on macroscopic inspection. There was, however, a linear correlation between the increase in NOx and the volume of venous blood added experimentally. NOx levels were significantly higher (P < 0.05) in young rats (6.5+/-0.2 microM) than in middle-aged rats (5.6+/-0.3 microM). There was no significant difference in CSF NOx among the four samples collected at 1-week intervals in 13-week-old rats. These results indicate that our CSF sampling technique can be used to reliably obtain a small amount of CSF for NOx measurement. This technique will facilitate further experimental studies of the involvement of CSF NO in neurogenic or inflammatory diseases.     

Cerebrospinal fluid superoxide dismutase and serum malondialdehyde levels in patients with aneurysmal subarachnoid hemorrhage: preliminary results

OBJECTIVES: Experimental studies provide evidence that oxidative damage plays a role in the development of vasospasm after aneurysmal subarachnoid hemorrhage (SAH) but data from human studies is still limited. The purpose of this study was to investigate the time course of cerebrospinal fluid (CSF) superoxide dismutase (SOD) and serum malondialdehyde (MDA) changes in patients with aneurysmal SAH. METHODS: SOD in CSF and MDA in the serum were detected on days 1-3, 5 and 7 after aneurysmal SAH in 21 patients, and the results were compared with 15 patients with hydrocephalus. The results were also compared with those of clinical parameters including the patient's outcome at 6 months. RESULTS: The mean CSF SOD levels were lower and serum MDA levels were higher than the controls. Patients with a high amount of blood within the cisterns had a trend to decreased SOD while increasing MDA levels. CONCLUSION: These preliminary results suggest that the levels of antioxidants are decreased after the onset of SAH in the early period, possibly because of increased oxidative stress. Reactive oxygen-mediated oxidative damage may play an important role in inflammation after SAH.     

Vasopressin and oxytocin in CSF and plasma of patients with aneurysmal subarachnoid haemorrhage

Objective

Clinicopathological studies on patients succumbing to subarachnoid haemorrhage (SAH) demonstrated hypothalamic lesions. The implication of the hypothalamic neuropeptides arginine-vasopressin (AVP) and oxytocin (OXT) has not been linked to aneurysmal SAH yet. This study investigates AVP and OXT in CSF and plasma of patients with spontaneous aneurysmal SAH and their association with outcome.

Methods

CSF and plasma samples of 12 patients with aneurysmal SAH were prospectively studied for 2 weeks. AVP and OXT were measured by radioimmunoassay. Outcome was assessed on Glasgow-Outcome-Scale. Twenty-nine patients without neuropsychiatric disturbances served as controls. Differences in neuropeptide concentration time courses were assessed by regression models. Group comparisons were performed by Kruskal–Wallis and correlations by Spearman tests.

Results

Regression of CSF levels between patients with poor and good outcome revealed significantly lower levels of AVP in patients with poor outcome (p = 0.012) while OXT showed a trend towards lower levels (p = 0.063). In plasma, no significant differences between outcome groups were found. Group comparisons between poor outcome patients and controls revealed significant differences in CSF for AVP (p = 0.001) and OXT (p = 0.015). In plasma, AVP yielded significantly different results while OXT did not. No differences were found between the good outcome group and controls. Plasma and CSF concentrations showed no significant correlation.

Conclusion

Patients with poor outcome after aneurysmal SAH have lower AVP and OXT levels in CSF than patients with good outcome while neuropeptide levels in plasma failed to reflect differences in outcome. The data indicate hypothalamic damage as an aetiologic factor for outcome after aneurysmal SAH.     

Astrocytic activation in relation to inflammatory markers during clinical exacerbation of relapsing-remitting multiple sclerosis

Summary The study aimed to assay the cerebrospinal fluid (CSF) levels of protein S100B, a biomarker of astrocyte activation in relation to kynurenic acid (KYNA) and nitric oxide (NO) metabolites, nitrate/nitrite (NOx) concentrations in acute relapse multiple sclerosis (MS) patients. Twenty relapsing-remitting MS (RR-MS) patients and 10 controls were enrolled. RR-MS patients were assessed on the expanded disability status scale (EDSS) and underwent lumbar puncture. The CSF KYNA, NOx and S100B levels were significantly higher in RR-MS group compared to controls (p = 0.01, 0.001, 0.04, respectively). There was a significant correlation between CSF S100B and KYNA (p = 0.01) but not NOx (p > 0.05) in RR-MS. CSF KYNA, NOx or S100B concentrations did not correlate with disease characteristics of MS patients. Our study suggests the activation of the kynurenine pathway leading to the increase of neuroprotective KYNA in the CSF of MS patients during acute relapse what contrasts with chronic phases of the disease.     

Acute decrease in cerebral nitric oxide levels after subarachnoid hemorrhage.

Disturbances in the nitric oxide (NO) vasodilatory pathway have been implicated in acute vasoconstriction and ischemia after subarachnoid hemorrhage (SAH). The authors hypothesize that blood released during SAH leads to vasoconstriction by scavenging NO and limiting its availability. This was tested by measuring the major NO metabolites nitrite and nitrate in five different brain regions before and after experimental SAH. The basal NO metabolites levels were as follows (mean +/- SD, micromol/mg wet weight): brain stem, 0.14 +/- 0.07; cerebellum, 0.12 +/- 0.08; ventral convexity cortex, 0.22 +/- 0.15; dorsal convexity cortex, 0.16 +/- 0.11; and hippocampus, 0.26 +/- 0.17. In sham-operated animals, no effect of the nitric oxide synthase (NOS) inhibitor L(G)-nitro-L-arginine-methyl-ester (30 mg/kg) was found on NO metabolites 40 minutes after administration, but a significant decrease was seen after 120 minutes. The NO metabolites decreased significantly 10 minutes after SAH in all brain regions except for hippocampus, and recovered to control levels in cerebellum at 60 minutes and in brain stem and dorsal cerebral cortex 180 minutes after SAH, while remaining low in ventral convexity cortex. Nitrite recovered completely in all brain regions at 180 minutes after SAH, whereas nitrate remained decreased in brain stem and ventral convexity cortex. Our results indicate that SAH causes acute decreases in cerebral NO levels by a mechanism other than NOS inhibition and provide further support for the hypothesis that alterations in the NO vasodilatory pathway contribute directly to the ischemic insult after SAH.     

Raised cerebrospinal fluid nitrite and nitrate levels in patients with multiple sclerosis: no correlation with disease activity

A growing body of evidence implicates excessive generation of nitric oxide (NO) within the central nervous system (CNS) in multiple sclerosis (MS). The aim of our study is to analyse nitrite and nitrate as end products of NO in the cerebrospinal fluid (CSF) from MS patients and correlate the concentrations with clinicol characteristics of the disease. CSF nitrite and nitrate concentrations were measured after reduction of nitrate, by Griess reaction, in 105 MS potients, 27 patients with non-inflammatory neurological disorders (NIND) and 13 individuals without neurological disorder (Co). Mean CSF nitrite and nitrate concentrations were significantly higher in patients with MS and NIND compared with the Co patients (9.44 and 8.68, respectively, versus 6.85 microM; P=0.0001 and P=0.031, respectively). There was no significant correlation between CSF nitrite and nitrate concentrations and activity, phase, severity and duration of MS. Our data are in agreement with the results of previous studies which have demonstrated raised concentrations of CSF NO metabolites in MS patients, providing further evidence for NO involvement in MS. The lack of correlation between NO metabolites and disease activity speaks in favour of the possible dual role of NO, as both immunoregulatory and pro-inflammatory molecule, in the pathogenesis of MS.     

Increased cerebrospinal fluid concentrations of asymmetric dimethylarginine correlate with adverse clinical outcome in subarachnoid hemorrhage patients

Elevated cerebrospinal fluid (CSF) concentrations of asymmetric dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide synthase, have been found in patients with subarachnoid hemorrhage (SAH). In addition, CSF levels of ADMA are associated with the severity of vasospasm. However, the relation between CSF ADMA levels and the clinical outcome of SAH patients is still unclear. We hypothesized that elevated ADMA levels in CSF might be related to the clinical outcome of SAH patients. CSF ADMA levels were measured in 20 SAH patients at days 3–5, days 7–9 and days 12–14 after SAH onset using high-performance liquid chromatography. Cerebral vasospasm was assessed by transcranial Doppler ultra sonography. Clinical outcome at 2 year follow-up was evaluated using the Karnofsky Performance Status scale (KPS). CSF ADMA concentrations in all SAH patients were significantly increased at days 3–5 (p = 0.002) after SAH, peaked on days 7–9 (p < 0.001) and remained elevated until days 12–14 (p < 0.001). In subgroup analysis, significant increases of CSF ADMA levels were found in patients both with and without vasospasm. The KPS scores significantly correlated with CSF levels of ADMA at days 7–9 (correlation coefficient = −0.55, p = 0.012; 95% confidence interval −0.80 to −0.14). Binary logistic regression analysis indicated that higher ADMA level at days 7–9 predicted a poor clinical outcome at 2 year follow-up after SAH (odds ratio = 1.722, p = 0.039, 95% confidence interval 1.029 to 2.882). ADMA may be directly involved in the pathological process and future adverse prognosis of SAH.     

Lower initial red blood cell count in cerebrospinal fluid predicts good functional outcome in patients with spontaneous subarachnoid haemorrhage

Background and purpose

Red blood cell (RBC) degradation after subarachnoid haemorrhage (SAH) negatively affects functional outcome. Although the detection of RBCs in the cerebrospinal fluid (CSF) is a widely available part of neurological routine diagnostics, the prognostic value as a biomarker remains unclear. This study was undertaken to investigate whether CSF RBC count correlates with established radiological markers of SAH volume and whether the CSF RBC count can predict functional outcome in SAH patients.

Methods

A total of 121 consecutive spontaneous SAH patients were retrospectively analyzed. CSF was collected from external ventricular drain as part of routine diagnostic procedures. We used multivariable binary logistic regression to investigate associations between CSF RBC counts and functional outcome 3 months after SAH or hospital survival. Good functional outcome was defined as modified Rankin Scale ≤ 2.

Results

Patients' age was 60 ± 14 years, and the median admission Hunt & Hess grade (H&H) was 4. CSF samples were collected 2 days after intensive care unit admission. High CSF RBC counts positively correlated with radiological measurements for SAH volume, for example, modified Fisher score (p = 0.002) and Hijdra ventricle score (p = 0.016). Multivariable regression analysis adjusted for age, H&H grade, modified Fisher and Hijdra scores showed that low CSF RBC counts predicted hospital survival (per 100,000 CSF RBCs: adjusted odds ratio [adjOR] = 0.74, 95% confidence interval [CI] = 0.61–0.89, p = 0.001) and good functional outcome after 3 months (per 100,000 CSF RBC: adjOR = 0.76, 95% CI = 0.60–0.96, p = 0.020).

Conclusions

CSF RBC counts correlate with radiographic scores quantifying SAH volume and may serve as an early independent biomarker for hospital survival and good functional 3-month outcome in patients requiring ventriculostomy after SAH.     

Impact of hyperglycemia on neurological deficits and extracellular glucose levels in aneurysmal subarachnoid hemorrhage patients

OBJECTIVE: Hyperglycemia after aneurysmal subarachnoid hemorrhage (SAH) is associated with serious complications. Blood glucose may indicate a target for therapy to prevent delayed ischemic neurological deficits (DIND) and improve outcome. The objective of this study was to investigate energy metabolism in the extracellular/cerebrospinal fluid and blood in relation to outcome. METHODS: Prospective non-randomized study was carried out in the intensive care unit (ICU) of university hospital (n = 170 aneurysmal SAH patients, age: 51.0 +/- 12.6 years old). Following approval by the ethics committee, a microdialysis catheter was inserted into the vascular territory of the aneurysm after clipping. Patients were studied for 165 +/- 84 hours and classified according to the presence of neurological symptoms as asymptomatic (n = 66) and symptomatic (n = 104): acute focal neurological deficits (AFND, n = 61) and delayed ischemic neurological deficits (DIND, n = 43). The microdialysates were analysed hourly for energy metabolites. Daily morning blood glucose and cerebrospinal fluid (CSF) levels (glucose and lactate) were determined. Six-month Glasgow outcome scale (GOS) was assessed. RESULTS: Hyperglycemia on admission and high blood glucose levels on the following days were significantly related to the presence of symptoms, most pronounced in patients with poor outcome (p<0.05). In symptomatic patients (high blood glucose), the lowest extracellular fluid (ECF) glucose concentrations were found, most pronounced in the AFND group (1.0 +/- 1.2 mmol/l). The anaerobic metabolites lactate, lactate/pyruvate ratio (LPR) and lactate/glucose ratio (LGR) were higher in symptomatic patients (p<0.001) indicating cerebral metabolic distress. CSF concentrations of glucose and lactate were of no specific value. CONCLUSION: This study confirms the relevance of hyperglycemia to neurological outcome in SAH patients. Cerebral glucose was significantly lower in AFND patients despite hyperglycemic blood levels. More detailed works are necessary to select risk patients for optimized targeted therapy to avoid insulin-induced cerebral metabolic crisis.     

Transforming growth factor-beta1 in the cerebrospinal fluid of patients with subarachnoid hemorrhage: titers derived from exogenous and endogenous sources.

Transforming growth factor-beta1 (TGF-beta1) is a fibrogenic cytokine that is involved in postinjury repair and is implicated in the etiology of postsubarachnoid hemorrhage (SAH) chronic communicating hydrocephalus. TGF-beta1 was measured by enzyme-linked immunosorbant assay (ELISA) in sequential samples of cerebrospinal fluid (CSF) in 11 patients with hydrocephalus after SAH; levels were seen to be biphasically elevated and sources were investigated. TGF-beta1 levels were compared with albumin levels that estimated CSF blood content. Control samples from nonhemorrhagic hydrocephalics were tested similarly. Mean total TGF-beta1 levels were elevated to 4400+/-3435 (+/-SD) pg/mL greater than control levels of 97+/-42 at 1 to 2 days posthemorrhage. Thereafter, levels fell to 714+/-401 by 5 to 6 days posthemorrhage, then rose to a second peak of 1667+/-774 at 9 to 10 days posthemorrhage, remaining significantly increased until 19 days posthemorrhage (P = 0.007). The first peak probably derived from extravasated platelets and correlated with increased albumin levels in the CSF. The second TGF-beta1 peak rose greater than CSF albumin levels that had stabilized at this time, and thus was attributed to a tissue-specific response rather than a re-bleed. TGF-beta1 was detected in the choroid secretory epithelium from controls, but levels were greater in SAH patients at 10 to 12 days posthemorrhage. The authors conclude that the elevated levels of TGF-beta1 in CSF after SAH are derived initially from blood and later from endogenous sources such as the choroid plexus.     

Cerebrospinal fluid creatine kinase-BB isoenzyme activity and outcome after subarachnoid hemorrhage.

BACKGROUND: The brain is rich in creatine kinase-BB isoenzyme activity (CK-BB), which is not normally present in cerebrospinal fluid (CSF). Results of previous studies have shown that CK-BB can be detected in the CSF of patients with aneurysmal subarachnoid hemorrhage (SAH), but whether CK-BB levels correlate with patients' neurologic outcomes is unknown. OBJECTIVE: To evaluate the relationship between CSF CK-BB level and outcome after SAH. DESIGN: Prospective observational cohort. SETTING: University-affiliated tertiary care center. PATIENTS: Convenience sample of 30 patients seen for cerebral aneurysm clipping. INTERVENTIONS: We sampled and assayed CSF for CK isoenzymes a median of 3 days after SAH in 27 patients, and at the time of unruptured aneurysm clipping in 3 patients. MAIN OUTCOME MEASURES: Without knowledge of CK results, we assigned the Glasgow Outcome Scale score early (approximately 1 week) and late (approximately 2 months) after surgery. RESULTS: Higher CSF CK-BB levels were associated with higher Hunt and Hess grades at hospital admission (Spearman rank correlation, p = 0.69; P<.001), lower Glasgow Coma Scale scores at hospital admission (p = -0.72; P<.001), and worse early outcomes on the Glasgow Outcome Scale (p = -0.64; P<.001). For patients with a favorable early outcome (Glasgow Outcome Scale score, 3-5), all CK-BB levels were less than 40 U/L. With a cutoff value of 40 U/L, CK-BB had a sensitivity of 70% and a specificity of 100% for predicting unfavorable early outcome (Glasgow Outcome Scale score, 1-2). Having a CK-BB level greater than 40 U/L increased the chance of an unfavorable early outcome, from 33% (previous probability) to 100%, whereas a CK-BB level of 40 U/L or less decreased it to 13%. Similar findings were obtained when considering late outcomes. CONCLUSION: The level of CSF CK-BB may help predict neurologic outcome after SAH.     

Oxyhemoglobin produces apoptosis and necrosis in cultured smooth muscle cells

Confluent rat aortic smooth muscle cells were treated with OxyHb in a concentration- and time-dependent manner. A high concentration of OxyHb (100 microM) within 24 h decreased cell density. DNA analysis showed a smear pattern characteristic of cell necrosis. Transmission electron microscopy demonstrated disintegration of the cell membrane and destruction of cell organelles. Western blotting using PARP antibody revealed that 116 kDa PARP was not cleaved to 85 kDa, an apoptosis-related fragment. On the contrary, a low concentration of OxyHb (10 microM) produced apoptotic cell death at 72 h that was supported by DNA analysis and TUNEL staining. These results demonstrated that a high level of OxyHb induced necrosis within 24 h and a low concentration of OxyHb produced apoptosis after 72 h in cultured smooth muscle cells. Morphological alterations induced by OxyHb might contribute to the vascular wall changes in the cerebral arteries following subarachnoid hemorrhage (SAH).     

Determination of cerebrospinal fluid concentrations of arginine and dimethylarginines in patients with subarachnoid haemorrhage

Elevated cerebrospinal fluid (CSF) concentrations of asymmetric dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide synthase (NOS), are assumed to be related to delayed vasospasm after subarachnoid haemorrhage (SAH). However, data on CSF concentrations of L-arginine, ADMA and its structural isomer symmetric dimethylarginine (SDMA) are very sparse in humans. We here present a new hydrophilic interaction chromatography-tandem mass spectrometry (HILIC-MS-MS) method for the precise determination of these substances in CSF. The method requires only minimal sample preparation and features isotope labeled internal standards. First data of patients with SAH showed that on the day of admission CSF concentration values of L-arginine and ADMA were not significantly different from controls, but increased markedly during the course of the hospital stay. The decrease of the L-arginine to ADMA ratio points to a progressive impairment of the NO production rate in the brain after SAH which is confirmed by a simultaneous decrease in nitrate and nitrite concentrations in CSF.     

CSF lipocalin-2 increases early in subarachnoid hemorrhage are associated with neuroinflammation and unfavorable outcome

Lipocalin-2 mediates neuro-inflammation and iron homeostasis in vascular injuries of the central nervous system (CNS) and is upregulated in extra-CNS systemic inflammation. We postulate that cerebrospinal fluid (CSF) and blood lipocalin-2 levels are associated with markers of inflammation and functional outcome in subarachnoid hemorrhage (SAH). We prospectively enrolled 67 SAH subjects, serially measured CSF and plasma lipocalin-2, matrix metallopeptidase 9 (MMP-9), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) on post-SAH days 1-5 and assessed outcome by modified Rankin Scale (mRS) every 3 months. Unfavorable outcome is defined as mRS > 2. Twenty non-SAH patients undergoing lumbar drain trial were enrolled as controls. Lipocalin-2 was detectable in the CSF and significantly higher in SAH compared to controls (p < 0.0001). Higher CSF LCN2 throughout post-SAH days 1-5 was associated with unfavorable outcome at 3 (p = 0.0031) and 6 months (p = 0.014). Specifically, higher CSF lipocalin-2 on post-SAH days 3 (p = 0.036) and 5 (p = 0.016) were associated with unfavorable 3-month outcome. CSF lipocalin-2 levels positively correlated with CSF IL-6, TNF-α and MMP-9 levels. Higher plasma lipocalin-2 levels over time were associated with worse 6-month outcome. Additional studies are required to understand the role of lipocalin-2 in SAH and to validate CSF lipocalin-2 as a potential biomarker for SAH outcome.     

Cerebrospinal fluid superoxide dismutase and serum malondialdehyde levels in patients with aneurysmal subarachnoid hemorrhage: preliminary results

Abstract

Objectives: Experimental studies provide evidence that oxidative damage plays a role in the development of vasospasm after aneurysmal subarachnoid hemorrhage (SAH) but data from human studies is still limited. The purpose of this study was to investigate the time course of cerebrospinal fluid (CSF) superoxide dismutase (SOD) and serum malondialdehyde (MDA) changes in patients with aneurysmal SAH.

Methods: SOD in CSF and MDA in the serum were detected on days 1–3, 5 and 7 after aneurysmal SAH in 21 patients, and the results were compared with 15 patients with hydrocephalus. The results were also compared with those of clinical parameters including the patient's outcome at 6 months.

Results: The mean CSF SOD levels were lower and serum MDA levels were higher than the controls. Patients with a high amount of blood within the cisterns had a trend to decreased SOD while increasing MDA levels.

Conclusion: These preliminary results suggest that the levels of antioxidants are decreased after the onset of SAH in the early period, possibly because of increased oxidative stress. Reactive oxygen-mediated oxidative damage may play an important role in inflammation after SAH.     

The effect of ecdysterone on cerebral vasospasm following experimental subarachnoid hemorrhage in vitro and in vivo

OBJECTIVES: Cerebral vasospasm has been the dreaded complication of ruptured intracranial aneurysms. Worldwide effort has led to many promising experimental treatments but none was confirmed to be effective in clinical trials. Ecdysterone is an insect steroid hormone. Our previous study showed that ecdysterone might prevent cerebral vasospasm in vitro. Even after all these works, rare attempts have been made to test the effect of ecdysterone on vascular adventitial fibroblast (VAF) proliferation, a process known to play an important role in various pathogenic vascular conditions. Thus, we tested the hypothesis that ecdysterone could affect VAF characteristics and have an effect on SAH induced cerebral vasospasm. METHODS: OxyHb of 100 microM was used in the in vitro study to mimic the clinical situation. The effect of OxyHb on the cell proliferation and migration of cultured aortic smooth muscle cells was investigated. In the in vivo study, 20 rabbits were equally divided into four groups: control group, SAH group, SAH/nimodipine group and SAH/ecdysterone group. Changes in neurological function and cerebral angiograms were observed after SAH. RESULTS: OxyHb increased the proliferation of vascular adventitial fibroblasts at 24 hours. Ecdysterone co-treatment was apparently similar to the suppression of proliferation. Cell cycle analysis indicated that ecdysterone inhibited the progression of vascular adventitial fibroblasts from G1 to S. The results of the migration assay showed that 100 microM OxyHb obviously prompted vascular adventitial fibroblast migration and that ecdysterone would attenuate this effect. In the SAH/nimodipine and SAH/ecdysterone groups, neurological deficit, cerebral vasospasm and structural changes in basilar artery were alleviated with nimodipine or ecdysterone treatment. CONCLUSION: Ecdysterone could affect vascular adventitial fibroblast characteristics and attenuate vasospasm after SAH.     

Elevated Cerebrospinal Fluid Protein Is Associated with Unfavorable Functional Outcome in Spontaneous Subarachnoid Hemorrhage

Background/objective: Subarachnoid hemorrhage (SAH) is a devastating neurologic event for which markers to assess poor outcome are needed. Elevated cerebrospinal fluid (CSF) protein may result from inflammation and blood-brain barrier (BBB) disruption that occurs during SAH. We sought to determine if CSF protein level is associated with functional outcome after SAH. Methods: We prospectively collected single-center demographic and clinical data for consecutive patients admitted with spontaneous SAH. Inclusion required an external ventricular drain and daily CSF protein and cellular counts starting within 48 hours of symptom onset and extending through 7 days after onset. Seven-day average CSF protein was determined from daily measured values after correcting for contemporaneous CSF red blood cell (RBC) count. Three-month functional outcome was assessed by telephone interview with good outcome defined as modified Rankin score 0-3. Variables univariately associated with outcome at P less than .25 and measures of hemorrhage volume were included for binary logistic regression model development. Results: The study included 130 patients (88% aneurysmal SAH, 69% female, 54.8 ± 14.8 years, Glasgow Coma Scale [GCS] 14 [7-15]). Three-month outcome assessment was complete in 112 (86%) patients with good functional outcome in 74 (66%). CSF protein was lower in good outcome (35.3 [20.4-49.7] versus 80.5 [40.5-115.5] mg/dL; P < .001). CSF protein was not associated with cerebral vasospasm, but delayed radiographic infarction on 3 to 12-month neuroimaging was associated with higher CSF protein (46.3 [32.0-75.0] versus 30.2 [20.4-47.8] mg/dL; P = .023). Good 3-month outcome was independently associated with lower CSF protein (odds ratios [OR] .39 [.23-.70] for 75th versus 25th percentile of protein; P = .001) and higher admission GCS (OR 1.23 [1.10-1.37] for good outcome per GCS point increase; P < .001). Parenchymal hematoma predicted worse outcome (OR 6.31 [1.58-25.25]; P = .009). Results were similar after excluding nonaneurysmal SAH and after including CSF RBC count, CT score, and intraventricular hemorrhage volume in models. Conclusions: Elevated average CSF protein is associated with poor outcome after spontaneous SAH. Further research should investigate if elevated CSF protein identifies patients in whom mechanisms such as BBB disruption contribute to poor outcome.