Post-GWAS multiomic functional investigation of the TNIP1 locus in Alzheimer's disease highlights a potential role for GPX3.

INTRODUCTION: Recent genome-wide association studies (GWAS) have reported a genetic association with Alzheimer's disease (AD) at the TNIP1/GPX3 locus, but the mechanism is unclear. METHODS: We used cerebrospinal fluid (CSF) proteomics data to test (n = 137) and replicate (n = 446) the association of glutathione peroxidase 3 (GPX3) with CSF biomarkers (including amyloid and tau) and the GWAS-implicated variants (rs34294852 and rs871269). RESULTS: CSF GPX3 levels decreased with amyloid and tau positivity (analysis of variance P = 1.5 × 10-5) and higher CSF phosphorylated tau (p-tau) levels (P = 9.28 × 10-7). The rs34294852 minor allele was associated with decreased GPX3 (P = 0.041). The replication cohort found associations of GPX3 with amyloid and tau positivity (P = 2.56 × 10-6) and CSF p-tau levels (P = 4.38 × 10-9). DISCUSSION: These results suggest variants in the TNIP1 locus may affect the oxidative stress response in AD via altered GPX3 levels. HIGHLIGHTS: Cerebrospinal fluid (CSF) glutathione peroxidase 3 (GPX3) levels decreased with amyloid and tau positivity and higher CSF phosphorylated tau. The minor allele of rs34294852 was associated with lower CSF GPX3. levels when also controlling for amyloid and tau category. GPX3 transcript levels in the prefrontal cortex were lower in Alzheimer's disease than controls. rs34294852 is an expression quantitative trait locus for GPX3 in blood, neutrophils, and microglia.

Does the Cerebrospinal Fluid Reflect Altered Redox State But Not Neurotrophic Support Loss in Parkinson's Disease?

Alteration in neurotrophic factors support and antioxidant defenses in the central nervous system (CNS) along with deficit of ferritin have been associated with idiopathic Parkinson's disease (PD). The objectives were to analyze in the cerebrospinal fluid (CSF) of patients with PD and controls the following: (i) the levels of the neuroprotectant factors glial cell line-derived neurotrophic factor, persephin, neurturin, and brain-derived neurotrophic factor, (ii) the levels of transforming growth factor-ß1 (TGFß1) and transforming growth factor-ß2 (TGFß2), proinflammatory factors, (iii) the activity of the antioxidant enzymes glutathione peroxidase (GPx), glutathione reductase (GR), glutathione-S-transferase (GST), catalase, superoxide dismutases (SODs), and peroxiredoxins (PRDxs), and (iv) ferritin levels. The study revealed that, among neurotrophic factors, only TGFß1 levels were found to be enhanced in patients with PD (early, p < 0.05; advanced, p < 0.02). Regarding antioxidant enzymes, the activity of GPx, catalase, and PRDxs, all hydrogen peroxide scavengers, was found to be significantly reduced in patients (GPx, p < 0.001; catalase, p < 0.01; PRDxs, p < 0.01, one-way analysis of variance). Finally, ferritin content in CSF was significantly diminished over time in patients (early, p < 0.01, -49%; advanced, p < 0.001, -80.7%). Our observations lead to the hypothesis that parkinsonian patients suffer from a serious disturbance of redox state in the CNS, as evaluated through the CSF, characterized by reduced hydrogen peroxide scavenging and iron storage.

Psychiatric patient stratification using biosignatures based on cerebrospinal fluid protein expression clusters.

Psychiatric disorders are caused by perturbed molecular pathways that affect brain circuitries. The identification of specific biosignatures that are the result of altered pathway activities in major depression, bipolar disorder and schizophrenia can contribute to a better understanding of disease etiology and aid in the implementation of diagnostic assays. In the present study we identified disease-specific protein biosignatures in cerebrospinal fluid of depressed (n: 36), bipolar (n: 27) and schizophrenic (n: 35) patients using the Reverse Phase Protein Microarray technology. These biosignatures were able to stratify patient groups in an objective manner according to cerebrospinal fluid protein expression patterns. Correct classification rates were over 90%. At the same time several protein sets that play a role in neuronal growth, proliferation and differentiation (NEGR1, NPDC1), neurotransmission (SEZ6) and protection from oxidative damage (GPX3) were able to distinguish diseased from healthy individuals (n: 35) indicating a molecular signature overlap for the different psychiatric phenotypes. Our study is a first step toward implementing a psychiatric patient stratification system based on molecular biosignatures. Protein signatures may eventually be of use as specific and sensitive biomarkers in clinical trials not only for patient diagnostic and subgroup stratification but also to follow treatment response.

Selenium speciation in paired serum and cerebrospinal fluid samples.

Se speciation was performed in 24 individual paired serum and cerebrospinal fluid (CSF) samples from neurologically healthy persons. Strong anion exchange (SAX) separation, coupled to inductively coupled plasma-dynamic reaction cell-mass spectrometry (ICP-DRC-MS), was employed. Species identification was done by standard matched retention time, standard addition and by size exclusion chromatography followed from SAX (2-D SEC-SAX-ICP-DRC-MS) and by SAX followed from CE-ICP-DRC-MS (2-D SAX-CE-ICP-DRC-MS). Limit of detection (LoD, 3×standard deviation (SD) of noise) was in the range of 0.026-0.031 µg/L for all investigated species and thus was set uniformly to 0.032 µg/L. Quality control for total Se determination was performed by analysing control materials "human serum" and "urine", where determined values met target values. Several Se species were found in both sample types having following median values (sequence: serum/CSF, each in µg Se/L): total Se, 58.39/0.86; selenoprotein P (SePP), 5.19/0.47; Se-methionine (SeM), 0.23/ 65 µg/L; however, SePP(-CSF) appeared independent of SePP(-serum). For Se-HSA(-serum) versus (vs.) Se-HSA(-CSF), a weak linear relationship was found (r(2)=0.1722). On the contrary, for anti-oxidative Se-enzymes, higher r (2) values were calculated: GPx(-serum) vs. GPx(-CSF), r(2)=0.3837; TrxR(-serum) vs. TrxR(-CSF), r(2)=0.6293. Q(-Se-species) values (= ratios of CSF(-Se-species)/serum(-Se-species)) were compared with the Q (-Alb) value (HSA(-CSF)/HSA(-serum)=clinical index of NB integrity) for deeper information about NB passage of Se species. The Q (-Se-HSA) value (3.8×10(-3)) was in accordance to the molecular mass dependent restriction at NB (Q(-Alb) at 5.25×10(-3)). Increased Q values were seen for TrxR (21.3×10(-3)) and GPx (8.3×10(-3)) which are not (completely) explained by molecular size. For these two anti-oxidative Se-enzymes (GPx, TrxR), we hypothesize that there might be either a facilitated diffusion across NB or they might be additionally synthesized in the brain.

The role of oxidative stress in perinatal hypoxic-ischemic brain injury.

INTRODUCTION: The pathogenesis of perinatal hypoxic-ischemic brain damage is highly complex. OBJECTIVE: The aim of this study was to assess the role of oxidative stress in hypoxic-ischemic brain injury and subsequent abnormal neurological outcome in infants with perinatal hypoxic-ischemic encephalopathy (HIE). We estimated perinatal oxidative brain damage measuring activity of glutathione peroxidase (GPX) in cerebrospinal fluid (CSF) as an indirect biomarker of free radical production during cerebral hypoxia-ischemia in correlation with the level of intracellular enzyme neuron specific enolase (NSE) in CSF as a biomarker of extend of brain injury. METHODS: Ninety neonates (>32 GA) with perinatal HIE were enrolled prospectively. HIE was categorized into three stages according Sarnat and Sarnat clinical scoring system and changes seen on amplitude integrated EEG. CSF for GPX analysis and NSE analysis was taken in the first 72 hours of life. Neurodevelopment outcome was assessed at 12 months of corrected gestational age. RESULTS: GPX activity in CSF was in good relation with clinical stage of HIE (p < 0.0001) and GA (p < 0.0001) and significantly corresponded with subsequent neurodevelopment outcome (p < 0.001). GPX activity in CSF showed a strong correlation with NSE levels in CSF (p < 0.001) as the biomarker of extent of brain injury. CONCLUSION: Our results suggest that oxidative stress might be important contributing factor in perinatal hypoxic-ischemic brain damage, particularly in preterm neonates.

Antioxidative enzymes activity and malondialdehyde concentration during mitoxantrone therapy in multiple sclerosis patients.

Mitoxantrone (MX) is approved for the treatment of aggressive relapsing-remitting, secondary-progressive and progressive-relapsing form of multiple sclerosis (MS). The mechanism of its action is multiaxial, however, it is not free from side effects. The causes of the side effects are still unknown and require further investigation. The aim of this study was to investigate the influence of MX therapy on enzymatic parameters of endogenous antioxidative status: manganese and copper/zinc superoxide dismutase (MnSOD, Cu/ZnSOD), catalase (CAT), glutathione peroxidase (GSH-Px) and lipid peroxidation marker--malondialdehyde (MDA) in blood serum and cerebrospinal fluid (CSF) in patients suffering from MS. After the MX therapy serum and the CSF MDA concentrations increased significantly. We reported that MnSOD activities decrease in serum and the CSF, while, surprisingly, the serum Cu/ZnSOD activity increases after the MX therapy. We also noted a marked decrease in CSF CAT and GSH-Px activity after the MX treatment. Our results strongly suggest the influence of MX therapy on oxidation/antioxidation status of serum and the CSF. These findings open up new opportunities for a better understanding of underlying physiopathological events in MS and provide a new insight into MX's mechanisms of action, especially its potent side effects.

New insights into the pathogenesis of perinatal hypoxic-ischemic brain injury.

BACKGROUND: Pathogenesis of perinatal hypoxic-ischemic brain injury (HIE) is complex. In this study, we examined the role of neuroinflammation, oxidative stress and growth factors in perinatal hypoxic-ischemic brain damage. METHODS: Ninety neonates (>32 weeks' gestation) with perinatal HIE were enrolled prospectively. Perinatal HIE was categorized into three stages according to the Sarnat and Sarnat clinical scoring system and changes seen on amplitude integrated electroencephalography. Cerebrospinal fluid (CSF) for interleukin-6 (IL-6) and glutathione peroxidase analysis was taken in the first 48 h of life and subsequent CSF for neuron-specific enolase (NSE) and vascular endothelial growth factor (VEGF) analysis 72 h after birth. Neurodevelopmental outcome was assessed at 12 months of corrected gestational age using the Denver Developmental Screening Test. RESULTS: Concentrations of NSE in CSF correlated with severity of HIE (P < 0.0001) and corresponded well with subsequent neurodevelopmental outcome. Concentrations of IL-6 in CSF were markedly increased in neonates with severe HIE (P < 0.0001) and those with subsequent neurological sequels, but were normal in the majority of neonates with mild and moderate HIE. Glutathione peroxidase activity in CSF was significant with the stage of HIE (P < 0.0001) and gestational age (P < 0.0001) and corresponded well with subsequent neurodevelopmental outcome. Advanced stage of HIE was associated with increased concentrations of VEGF in CSF (P < 0.0001). Neurological outcomes at 12 months of age correlated best with CSF level of NSE (P < 0.001) and IL-6 (P < 0.001). CONCLUSION: Our results suggest that neuroinflammation plays a principal role in perinatal hypoxic-ischemic brain damage and we postulate that oxidative stress and upregulation of VEGF might be important contributing factors in the pathogenesis of hypoxic-ischemic brain injury, particularly in preterm neonates.

Effect of high-dose phenobarbital on oxidative stress in perinatal asphyxia: an open label randomized controlled trial.

OBJECTIVE: To evaluate the effect of high dose phenobarbital on lipid peroxidation and antioxidant enzymes in perinatal asphyxia. DESIGN: Open label, Randomized controlled trial. SETTING: Neonatal intensive care unit of a tertiary care teaching hospital. PARTICIPANTS: 72 full term inborn neonates with severe birth asphyxia. METHODS: Neonates were randomized to Study (phenobarbital) group and Control group. The infants in the study group received phenobarbital infusion (40 mg/kg) within first two hours of life while babies in the control group did not receive any phenobarbital. Rest of the management in both the groups was as per the unit protocol for the management of hypoxic ischemic encephalopathy. A cerebrospinal fluid examination was done at 12 ± 2 hours of life to determine the levels of superoxide dismutase, glutathione peroxidise and malonyldialdehyde. 60 neonates were followed up at 1 month of age when a detailed neurological examination was done. RESULTS: Four neonates in the study group and six neonates in the control group died during the study. Two neonates in the study group were lost to follow up. The cerebrospinal fluid lipid peroxides and antioxidant enzymes were significantly lower in the phenobarbital group as compared to the control group. The neurological outcome at one month follow up was found to be comparable between the two groups. CONCLUSION: Phenobarbital (40 mg/kg) given in the first two hours of life in term neonates with perinatal asphyxia led to a decrease in CSF levels of lipid peroxides and antioxidant enzymes at 12 ± 2 hours of life.

Oxidative stress in mice infected with Angiostrongylus cantonensis coincides with enhanced glutathione-dependent enzymes activity.

This study aimed to estimate reactive oxygen species (ROS) production, antioxidants activity, and biomarkers level of oxidative damage to protein and DNA in the cerebrospinal fluid (CSF) of C57BL/6 mice infected with Angiostrongylus cantonensis. The mean ROS concentration in the CSF of infected mice increased gradually, and the increase in ROS in CSF became statistical significance at days 12-30 post-infection compared to that before infection (P<0.001), and then ROS returned to normal level at day 45 after infection. In parallel with the increase in ROS in the CSF, infected mice showed similar of changes in reduced glutathione (GSH), glutathione reductase (GR), glutathione peroxidase (GPx), and glutathione S-transferase (GST) as that in ROS in the CSF. GSH, GR, GPx, and GST in the CSF of infected mice were all significantly higher than they were before infection during days 12-30 post-infection. However, protein carbonyl content and 8-hydroxy-2'-deoxyguanosine, biomarkers of oxidative damage to protein and DNA, respectively, were also significantly higher in the CSF of infected mice during this period. These results suggest that oxidative stress occur in the cells of central nervous system of mice infected with A. cantonensis during days 12-30 after infection due to ROS overproduction in CSF despite the increase in antioxidants during this period.

Glutathione peroxidase and subarachnoid hemorrhage: implications for the role of oxidative stress in cerebral vasospasm.

OBJECTIVE: Worldwide, cerebral vasospasm after subarachnoid hemorrhage (SAH) has an estimated morbidity and mortality of 1.2 million annually. While it has long been suspected that reactive oxygen species play a major role in the etiology of cerebral vasospasm after SAH, promising results in animal work were not borne out in human clinical trials, despite intensive research effort. The purpose of this study is to investigate the role of glutathione peroxidase in the SAH cerebrospinal fluid milieu. METHODS: We utilized commercially available kits for the quantitation of glutathione peroxidase 1 (glutathione peroxidase) activity and oxygen radical capacity and sodium dodecyl sulfate polyacrylamide gel electrophoresis with Western blotting with specific antibodies to human glutathione peroxidase to determine the enzyme content of the cerebrospinal fluid samples. Human cerebrospinal fluid was obtained in an Institutional Review Board-exempt manner for this study in the following groups: control (no SAH), CSF(C) (SAH but no vasospasm on angiography) and CSF(V) (SAH with clinical and angiographic vasospasm). RESULTS: We found that glutathione peroxidase activity is significantly higher in CSF(V) compared with CSF(C), and this is reflected in a higher total oxidative capacity in CSF(V). Despite similar levels of glutathione peroxidase protein, CSF(V) had significantly greater activity than CSF(C). DISCUSSION: These results further elucidate previous research from this laboratory, showing increased oxidative stress in CSF(V) compared with CSF(C). In conclusion, there appears to be increased glutathione peroxidase activity in CSF(V), despite there being increased levels of oxidative stress markers, suggesting overwhelming oxidative stress may play a role in cerebral vasospasm after SAH.

Antioxidant enzyme dysfunction in monocytes and CSF of Hispanic women with HIV-associated cognitive impairment.

HIV-associated cognitive neurological disorders (HAND) prevail in the antiretroviral therapy era. Proteomics analysis of CSF revealed expression of Cu/Zn superoxide dismutase (Cu/Zn SOD) in Hispanic women with cognitive impairment (CI). We tested the hypothesis that there is reduced capacity of antioxidant enzymes in CI by measures of expression and activity of Cu/Zn SOD, catalase, and Se-glutathione peroxidase in HAND. Our results showed that the function of these antioxidants was decreased in the CSF and monocytes of women with CI. These findings have important implications regarding their possible contribution to oxidative stress and in the diagnosis and therapy for HAND.

Aging and oxidative stress in progressive supranuclear palsy.

Progressive supranuclear palsy (PSP) is a neurodegenerative disorder, which may possibly be induced by oxidative stress. However, the age-related alteration of the endogenous antioxidant system is not well understood. To better understand this, we measured Cu/Zn-superoxide dismutase (SOD), glutathione peroxidase (GPx), and 4-hydroxynonenal (HNE)-conjugated GPx in cerebrospinal fluid of PSP patients by enzyme linked immunosorbent assay. A significant increase in the Cu/Zn-SOD level was detected in PSP group compared with controls. The levels of Cu/Zn-SOD and GPx in PSP group showed positive correlations with age. Two-thirds of total GPx was present as the HNE-conjugated form with positive correlation in PSP group. In conclusion, the endogenous antioxidant system of PSP patients appears to be activated with aging, however, it might be unable to function effectively because of conjugation with HNE.

A comparative study of nitric oxide, glutathione, and glutathione peroxidase activities in cerebrospinal fluid from children with convulsive diseases/children with aseptic meningitis.

It has been reported that active oxygen and/or free radicals are produced in the central nervous system (CNS) compartment in patients with bacterial meningitis, so it is supposed that the levels of endogenous antioxidative scavengers in the cerebrospinal fluid (CSF) are elevated as an adaptive reaction to bacterial meningitis, which exerts severe stress on the human body. We assumed that they are also elevated in patients with convulsive diseases. Nitric oxide (NO) and endogenous antioxidative scavengers (glutathione (GSH), glutathione peroxidase (GPX), (total) superoxide dismutase (T-SOD), manganese superoxide dismutase (Mn-SOD), and catalase) were measured in CSF from a group of child patients with various neurological diseases and a control group. NO, GSH, and GPX activities in CSF from the patients with convulsive diseases were significantly higher than in those with aseptic meningitis or in the controls. Furthermore, all parameters in CSF from patients with bacterial meningitis were significantly higher than in any other group. The present study suggests that oxidative stress may be associated with the pathophysiology of convulsion and that its clinical attenuation will lead to improvement in the prognosis for convulsive diseases.

Alterations in antioxidant enzyme activities in cerebrospinal fluid related with severity of hypoxic ischemic encephalopathy in newborns.

BACKGROUND: The antioxidant status of the tissue affected by ischemia-reperfusion is of great importance for the primary endogenous defense against the free-radical-induced injury. OBJECTIVE: In this study, we aimed to evaluate the relationship between the activities of antioxidant enzymes [superoxide dismutase (SOD), glutathione peroxidase (GPX), and catalase (CAT)] in cerebrospinal fluid (CSF) and severity of hypoxic-ischemic encephalopathy (HIE) in newborns. METHODS: Thirty full-term asphyxiated infants (gestational age >37 weeks) and 11 full-term infants (none of whom showed any signs of asphyxia) were included in this study. Activities of SOD, GPX, and CAT in CSF were measured within the first 72 h of life in infants with HIE and controls. RESULTS: Activity of SOD in CSF was significantly higher in infants with HIE compared with controls (p<0.05). GPX and CAT activities were higher in infants with HIE than they were in controls; however, the differences were not statistically significant (p > 0.05). The activities of GPX and CAT were significantly increased in severe HIE as compared with mild HIE and controls (p < 0.05). CONCLUSION: Both the duration of the hypoxic-ischemic insult and the severity of HIE modulate elevations of enzymatic activity as an adaptive response to excessive free radical production in CSF in newborn infants with HIE. The activities of antioxidant enzyme alterations in CSF correspond highly to the severity of HIE, and these patterns may be useful for diagnostic and prognostic purposes.

Effect of phenobarbital on free radicals in neonates with hypoxic ischemic encephalopathy--a randomized controlled trial.

BACKGROUND: Phenobarbital is one of the oldest, cheapest and easily available cerebroprotective drugs for the hypoxic brain. However, its potential and various actions have not been fully explored. AIM: To evaluate the effects of Phenobarbital on levels of oxidants and anti-oxidants in term and near term neonates with hypoxic ischemic encephalopathy. METHODS: Design--randomized controlled trial. Setting--tertiary care referral perinatal centre. Procedure--asphyxiated neonates (gestation > or = 34 weeks) with HIE were randomized to receive Phenobarbital 20 mg/kg i.v. within first six hours of life or to control group. CSF levels of malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GPx) and blood levels of vitamins A and E were estimated at 10-12 hours of age. RESULTS: CSF levels of MDA, SOD, GPx and blood levels of vitamins A and E were significantly lower in the Phenobarbital group (p<0.001). There was a trend towards lower levels of CSF MDA, SOD, GPx and blood vitamins A and E in babies with normal outcome as compared to babies with adverse outcome (death or neurologically abnormal at discharge). CONCLUSION: Phenobarbital in the dose of 20 mg/kg i.v. given within 6 hours of life in term and near-term neonates with HIE, was associated with a decrease in lipid peroxides, anti-oxidant enzymes and anti-oxidant vitamins.

[Decreased antioxidant-defence mechanisms in cerebrospinal fluid (CSF) in patients with tick-borne encephalitis (TBE)]. / Obnizenie mechanizmów obrony antyoksydacyjnej w plynie mózgowo-rdzeniowym u chorych z kleszczowym zapaleniem mózgu.

14 patients with Tick-borne Encephalitis (TBE) aged 21-64 (mean = 42.3) were analysed. The activity of superoxide dismutase (SOD), glutathione reductase (GSSG-R), glutathione peroxidase (GSH-Px), concentrations of malondialdehyde (MDA) and total sulphydryl groups (-SH) were measured in cerebrospinal fluid (CSF). Control group consisted of 10 patients whose CSF parameters remained in normal range. The CSF examination was performed twice: before and 3 weeks after treatment. The analysed activity of SOD, GSH-Px, GSSG-R, MDA and total sulphydryl groups (-SH) during the acute stage of the disease was significantly lower comparing to the control group. Despite the treatment, GSSG-R activity, MDA concentration and total sulphydryl groups--SH further lowered significantly. Although the SOD activity in CSF was higher in the second examination, it remained significantly lower comparing to the control group. We showed that the GSH-Px and GSSG-R activity in CSF after the acute stage of the TBE remained significantly lower than in the control group. Our examinations prove that during the TBE an increased generation of oxygen-derived free radicals occurs what shows decreased activity of the antioxidant parameters (SOD, GSH-Px, GSSG-R) and decreased concentration of total sulphydryl groups--SH in CSF. Our results suggest that during TBE, molecular structures injury of enzymes and antioxidative reactive cofactors may occur.

[Evaluation of oxidoreductive potential of patients with neuroborreliosis]. / Ocena potencjalu oksydoredukcyjnego u chorych z neuroborelioza.

AIM: The purpose of the study was to evaluate parameters of oxidoreductive system in serum and cerebrospinal fluid (CSF) of patients with neuroborreliosis. MATERIAL AND METHODS: The cases were 25 patients aged 21 to 64 (x = 42.3) hospitalized with diagnosis of neuroborreliosis. Activity of superoxide dismutase (Cu, Zn-SOD), glutathione reductase (GSSG-R), glutathione peroxidase (GSH-Px) and concentration of sulphydryl groups (-SH) and malondialdehyde (MDA) in serum and CSF were tested. The control group consisted of 10 patients with diagnosis of discopathy. An examination was performed twice: before and after treatment. RESULTS: Results of the study showed lack of stability in an oxidoreductive system during neuroborreliosis both in serum and in CSF. In CSF activity of SOD was increased while activity of GSH-Px and GSSG-R were decreased. Also concentration of -SH and lipid peroxidation products measured as MDA were increased. The increase of SOD, GSH-Px, GSSG-R activity and concentration of -SH and MDA in serum were detected. CONCLUSIONS: Disorders of an oxidoreductive system in CSF and serum during neuroborreliosis were observed. These changes persisted despite treatment and normalization of inflammatory CSF markers.

Free oxygen radicals--predictors of neonatal outcome following perinatal asphyxia.

The study was undertaken to evaluate the role of free oxygen radicals in asphyxiated neonates. Thirty term neonates appropriate for gestational age and with severe birth asphyxia (Apgar score of 3 or less at 1 minute of life) formed the study subjects. The levels of superoxide dismutase (SOD), glutathione peroxidase (GPx), creatine phosphokinase (CPK) and lipid peroxidase (LPO) in the CSF of these neonates were estimated between 12 and 48 hrs of life. Enzyme estimation was performed by standard methods and the results were analysed statistically using Multivariate Logistic Regression analysis and non parametric tests namely Kruskal Wallis test and Wilcoxon's rank sum test. Out of the thirty babies, 14 were observed to be neurologically normal, 9 had significant morbidity and 7 died. The SOD levels ranged from 12.4 to 140 units/ml, GPx from 128 to 1933 nmol/min/dl, CPK from 2 to 2098 IU/dl and LPO from 5.4 to 30.8 umol/hr/dl. The SOD and GPx levels had an inverse relationship whereas rise in LPO and CPK levels were directly proportional to the extent of neurological damage and ultimate clinical outcome. CPK levels higher than 140 IU/ml were lethal and associated with 100% mortality whereas all normal neonates had CPK below 37 IU/ml. The levels of antioxidant enzymes can reliably and significantly predict mortality and morbidity whereas level of an enzyme cannot confidently confer normalcy. Hence antioxidant enzyme levels with a cut off value can be a useful marker and serve as a prognostic indicator in times to come.

Malondialdehyde, glutathione peroxidase, and superoxide dismutase in cerebrospinal fluid during cerebral vasospasm in monkeys.

Cerebral vasospasm may result from lipid peroxidation induced by oxyhemoglobin in the subarachnoid space after subarachnoid hemorrhage. To test this theory, vasospasm was induced in monkeys by intrathecal injections of oxyhemoglobin or supernatant fluid from autologous blood incubated in vitro. Concentration of malondialdehyde (MDA), a product of lipid peroxidation, was elevated in cerebrospinal fluid (CSF) in association with vasospasm caused by oxyhemoglobin and supernatant fluid. Intrathecal injections of methemoglobin or bilirubin did not cause vasospasm or increased CSF MDA. Activity of glutathione peroxidase in CSF increased significantly after injection of oxyhemoglobin and methemoglobin. There were no significant changes in CSF superoxide dismutase activity although there was a trend towards higher activities in animals treated with oxyhemoglobin, methemoglobin, bilirubin, and supernatant fluid. These results show oxyhemoglobin-induced vasospasm is associated with MDA and lipid peroxidation in the subarachnoid space. Furthermore, detection of peroxidation products after injection of oxyhemoglobin in the absence of erythrocyte membranes indicates that oxyhemoglobin may directly damage cerebral arteries and brain by inducing lipid peroxidation in these structures. Depletion of free-radical scavenging enzymes in CSF did not seem necessary for development of vasospasm. In fact, there was a tendency for vasospasm to elevate enzyme activities, as if production of scavengers was induced by excess free radicals in the subarachnoid space.