Changes in levels of oxidative stress markers and some neuronal enzyme activities in cerebrospinal fluid of multiple sclerosis patients.

OBJECTIVES: The aim of the present study was to assess cerebrospinal fluid (CSF) levels of malondialdehyde (MDA), F2 isoprostanes (8-iso-PGF2α) and total antioxidant status (TAS) in relapsing-remitting (RR) and secondary progressive (SP) course of MS and neurological controls. These parameters were correlated with brain tissue damage parameters - neuron-specific enolase and 3´,5´-cAMP-phosphodiesterase (PDE) in CSF. METHODS: CSF samples were obtained from MS patients divided into two groups according to the disease severity (EDSS) - RR and SP course of MS. Control group composed of neurological diagnoses without demyelination and neurodegeneration. 8-iso-PGF2α and NSE levels in the CSF samples were determined using specific immunochemistry assays. MDA levels in the CSF were measured by HPLC method after reaction with thiobarbituric acid in acidic conditions. TAS and total PDE activity of CSF was determined spectrophotometrically. RESULTS: There were significant differences in CSF MDA levels between MS group and controls and also between RR and SP disease course. By contrast, CSF levels of 8-iso-PGF2α in MS group and both forms of MS were comparable to control values. In addition, the results show increased CSF levels of PDE in MS group and no changes of NSE in CSF between MS and control group. CONCLUSION: These findings point to a possibility of using the parameters of different specificity to lipid peroxidation for monitoring different stages (acute/progressive) of MS. This study support the idea, that combination of CSF markers is important for monitoring overall brain tissue pathology in MS.

Lipid peroxidation in the pathogenesis of neuroborreliosis.

This study analyzed the onset of lipid peroxidation (LPO) in neuroborreliosis and the effects of ceftriaxone therapy on LPO. Twenty-two patients with early neuroborreliosis and 22 healthy subjects were studied. LPO in the cerebrospinal fluid (CSF), as well as the plasma and urine was estimated by the levels of reactive aldehydes: 4-hydroxynonenal (4-HNE), 4-hydroxyhexenal, malondialdehyde, and 4-oxononenal, F2-isoprostanes and A4/J4-neuroprostanes (NPs). The plasma level of 4-HNE-protein adducts arachidonic acid (AA), docosahexaenoic acid (DHA) and vitamin E was determined. Additionally, enzymatic activities of phospholipase A2 (PLA2), platelet-activating factor acetylhydrolase (PAF-AH) and glutathione peroxidase (GSH-Px) were determined. A decrease of AA, DHA levels and GSH-Px activity in plasma was associated with a significant increase of aldehydes in the CSF, plasma and urine. Similarly, the increase of F2-isoprostanes and NPs in the CSF and plasma was associated with the decreased activity of PLA2 and PAF-AH. Ceftriaxone therapy cured patients and reduced the levels of F2-isoprostanes, NPs and reactive aldehydes. However, the activities of PLA2 and PAF-AH increased. Pathophysiological association of neuroborreliosis with systemic LPO was revealed. Effective antibiotic therapy attenuated LPO. Biomarkers of LPO could be useful to monitor the onset of neuroborreliosis and show the effectiveness of pharmacotherapy.

Novel relationships between B12, folate and markers of inflammation, oxidative stress and NAD(H) levels, systemically and in the CNS of a healthy human cohort.

OBJECTIVE: To evaluate the relationship between folate, cobalamin (Cbl), and homocysteine (Hcy), and markers of inflammation and oxidative stress within the periphery and central nervous system (CNS) of a healthy human cohort. METHODS: Thirty-five matched cerebrospinal fluid (CSF) and plasma samples were collected from consenting participants who required a spinal tap for the administration of anaesthetic. Plasma concentrations of Hcy and both plasma and CSF levels of folate, Cbl, nicotinamide adenine dinucleotide (NAD(H)) and markers of inflammation (interleukin-6, IL-6), and oxidative stress (F2-isoprostanes, 8-hydroxy-2'-deoxyguanosine (8-OHdG), and total antioxidant capacity (TAC)) were quantified. RESULTS: In the peripheral circulation, positive associations were observed between plasma folate and Cbl, and plasma TAC (P ≤ 0.01; P ≤ 0.01) and plasma NAD(H) (P ≤ 0.05; P ≤ 0.05) levels, respectively. Plasma folate was inversely associated with plasma Hcy concentrations (P ≤ 0.05); however, no statistically significant relationships were observed between plasma Hcy and plasma markers of inflammation, oxidative stress, or [NAD(H)]. Within the CNS plasma Hcy correlated positively with CSF IL-6 (P ≤ 0.01) and negatively with CSF NAD(H) (P ≤ 0.05) concentrations. An inverse association was observed between CSF folate and CSF levels of IL-6 (P ≤ 0.05). Unexpectedly, a positive association between CSF Cbl and CSF 8-OHdG levels was also found (P ≤ 0.01). DISCUSSION: These results indicate that folate and Cbl concentrations may influence the levels of oxidative damage, inflammation, and NAD(H), both systemically and within the CNS.

Cerebrospinal fluid biomarkers for neuropsychological symptoms in early stage of late-onset Alzheimer's disease.

PURPOSE: In addition to testing blood, cerebrospinal fluid (CSF) has been analyzed in the search for biomarkers. The aim of this study was to identify biomarkers in CSF for neuropsychological symptoms in early-stage late-onset Alzheimer's disease (LOAD). METHODS: CSF levels of beta-amyloid 1-42 (Aß42), F2-isoprostanes (F2-IsoPs) and F4-neuroprostanes (F4-NPs) were assayed in nine patients with mild Alzheimer's disease (AD), nine patients with amnestic mild cognitive impairment (a-MCI) and nine individuals with normal mental function. The three groups underwent neuropsychological testing. RESULTS: CSF levels of F2-IsoPs and F4-NPs did not significantly differ among the three groups. Aß42 in CSF was significantly higher in the control group compared with the mild AD group (p < 0.001) and a-MCI group (p = 0.03). There was a significant positive correlation between the level of F2-IsoPs and Aß42 in the a-MCI group and between the level of F2-IsoPs and F4-NPs in the mild AD group. In comparisons between the mild AD group and a-MCI group combined, the cognitive impairment (CI) group, with the control group, the median levels of F2-IsoPs and F4-NPs were significantly higher in the CI group and median level of Aß42 was significantly lower in the CI group. Both the levels of F2-IsoPs and Aß42 were significantly negatively correlated with paranoid and delusional ideation and total score for the Behavioral Pathology in Alzheimer's Disease Scale (BEHAVE-AD). CONCLUSIONS: The findings suggest CSF levels of Aß42 and F2-IsoPs are associated with the severity of neuropsychological symptoms.

History of cigarette smoking in cognitively-normal elders is associated with elevated cerebrospinal fluid biomarkers of oxidative stress.

BACKGROUND: Cigarette smoking in adults is associated with abnormalities in brain neurobiology. Smoking-induced central nervous system oxidative stress (OxS) is a potential mechanism associated with these abnormalities. The goal of this study was to compare cognitively-normal elders on cerebrospinal fluid (CSF) levels of F2-isoprostane biomarkers of OxS. METHODS: Elders with a lifetime history of smoking (smokers; n=50; 75±5 years of age; 34±28 pack-years; approximately 12% were actively smoking at the time of study) were compared to never-smokers (n=61; 76±6 years of age) on CSF iPF2α-III and 8,12, iso-iPF2α-VI F2-isoprostanes levels. F2-isoprostanes levels were quantitated with HPLC-atmospheric pressure chemical ionization-tandem mass spectrometry. Associations between F2-isoprostanes levels, hippocampal volumes, and cigarette exposure measures were also evaluated. RESULTS: Smokers showed higher iPF2α-III level than never-smokers. An age×smoking status interaction was observed for 8,12, iso-iPF2α-VI, where smokers demonstrate a significantly greater concentration with increasing age than never-smokers. In smokers only, higher 8,12, iso-iPF2α-VI concentration was associated with smaller hippocampal volume, and greater iPF2α-III level was related to greater pack years. CONCLUSIONS: This is the first study to demonstrate that a history of cigarette smoking in cognitively-normal elders was associated with significantly elevated CSF F2-isoprostane levels and greater age-related increases in F2-isoprostanes, and that higher F2-isoprostane levels in smokers were related to smaller hippocampal volume. These findings provide additional novel evidence that a history of chronic smoking during adulthood is associated with adverse effects on the human brain that are potentially enduring even with extended smoking cessation.

Influence of lifestyle modifications on age-related free radical injury to brain.

IMPORTANCE: The Healthy Brain Initiative 2013-2018 seeks to optimize brain health as we age. Free radical injury is an important effector of molecular and cellular stress in the aging brain that derives from multiple sources. OBJECTIVE: To identify potentially modifiable risk factors associated with increased markers of brain oxidative stress. DESIGN, SETTING, AND PARTICIPANTS: This cross-sectional, academic multicenter study consisted of 320 research volunteers (172 women) aged 21 to 100 years who were medically healthy and cognitively normal. MAIN OUTCOMES AND MEASURES: Free radical injury to the brain was assessed using cerebrospinal fluid (CSF) F2-isoprostane (F2-IsoP) concentrations correlated with age, sex, race, cigarette smoking, body mass index, inheritance of the ε4 allele of the apolipoprotein E gene (APOE), and CSF biomarkers of Alzheimer disease. RESULTS: The concentration of CSF F2-IsoP increased with age by approximately 3 pg/mL (approximately 10%) from age 45 to 71 years in medically healthy, cognitively normal adults (P < .001). The CSF F2-IsoP concentration increased by approximately more than 10% for every 5-U increase in body mass index (P < .001). Current smoking had an approximately 3-fold greater effect on CSF F2-IsoPs compared with age (P < .001). Women had greater mean CSF F2-IsoP concentrations than men at all ages after adjusting for other factors (P = .02). Neither the concentration of CSF Alzheimer disease biomarkers nor inheritance of the APOE ε4 allele was associated with the CSF F2-IsoP concentration in this group of medically healthy, cognitively normal adults (P > .05). The association between CSF F2-IsoP concentrations and race was not significant after controlling for the effect of current smoking status (P = .45). CONCLUSIONS AND RELEVANCE: Our results are consistent with an age-related increase in free radical injury in the human brain and uniquely suggest that this form of injury may be greater in women than in men. Our results also highlighted 2 lifestyle modifications (ie, body mass index and smoking) that would have an even greater effect on suppressing free radical injury to the brain than would suppressing the processes of aging. These results inform efforts to achieve success in the Healthy Brain Initiative 2013-2018.

Cerebrospinal fluid levels of inflammation, oxidative stress and NAD+ are linked to differences in plasma carotenoid concentrations.

BACKGROUND: The consumption of foods rich in carotenoids that possess significant antioxidant and inflammatory modulating properties has been linked to reduced risk of neuropathology. The objective of this study was to evaluate the relationship between plasma carotenoid concentrations and plasma and cerebrospinal fluid (CSF) markers of inflammation, oxidative stress and nicotinamide adenine dinucleotide (NAD+) in an essentially healthy human cohort. METHODS: Thirty-eight matched CSF and plasma samples were collected from consenting participants who required a spinal tap for the administration of anaesthetic. Plasma concentrations of carotenoids and both plasma and cerebrospinal fluid (CSF) levels of NAD(H) and markers of inflammation (IL-6, TNF-α) and oxidative stress (F2-isoprostanes, 8-OHdG and total antioxidant capacity) were quantified. RESULTS: The average age of participants was 53 years (SD=20, interquartile range=38). Both α-carotene (P=0.01) and ß-carotene (P<0.001) correlated positively with plasma total antioxidant capacity. A positive correlation was observed between α-carotene and CSF TNF-α levels (P=0.02). ß-cryptoxanthin (P=0.04) and lycopene (P=0.02) inversely correlated with CSF and plasma IL-6 respectively. A positive correlation was also observed between lycopene and both plasma (P<0.001) and CSF (P<0.01) [NAD(H)]. Surprisingly no statistically significant associations were found between the most abundant carotenoids, lutein and zeaxanthin and either plasma or CSF markers of oxidative stress. CONCLUSION: Together these findings suggest that consumption of carotenoids may modulate inflammation and enhance antioxidant defences within both the central nervous system (CNS) and systemic circulation. Increased levels of lycopene also appear to moderate decline in the essential pyridine nucleotide [NAD(H)] in both the plasma and the CSF.

F2-isoprostanes: a measure of oxidative stress in children receiving treatment for leukemia.

Acute lymphoblastic leukemia (ALL) is the most prevalent and curable cancer among children and adolescents less than 15 years of age in the United States. Essential for cure of childhood ALL is prophylactic treatment of the central nervous system (CNS), with methotrexate (MTX) being the most widely used drug in this treatment. While CNS treatment has contributed to long-term disease-free survival, resulting declines in academic abilities have been reported. There is growing evidence that CNS treatment with MTX increases oxidative stress, a potential mechanism of CNS injury. This article reports changes in oxidative stress, measured by the biomarker F2-isoprostane (F2-IsoP), in the cerebrospinal fluid (CSF) in 47 children with ALL during the first 18 months of treatment. The number of CSF samples ranged from 5 to 14 during postinduction and from 1 to 9 during continuation. Total doses of intrathecal MTX during postinduction were significantly correlated with the mean and highest concentrations of F2-IsoP during postinduction and the mean concentration of F2-IsoP during continuation. F2-IsoP concentrations during postinduction and continuation were higher in children who received more than six doses of intrathecal MTX. New therapies for a highly curable disease such as childhood leukemia have the potential to be individualized in the future, requiring reliable molecular and biochemical markers, such as oxidative stress indicators. Innovative use of biomarkers has the potential to increase our understanding of treatment-related toxicities and associated symptoms and to inform future therapeutic approaches for optimizing cure and quality of life among children with leukemia.

Analytical variables affecting analysis of F2-isoprostanes and F4-neuroprostanes in human cerebrospinal fluid by gas chromatography/mass spectrometry.

F2-isoprostanes (F2-IsoPs) are a gold marker of lipid peroxidation in vivo, whereas F4-neuroprostanes (F4-NPs) measured in cerebrospinal fluid (CSF) or brain tissue selectively indicate neuronal oxidative damage. Gas chromatography/negative-ion chemical-ionization mass spectrometry (GC/NICI-MS) is the most sensitive and robust method for quantifying these compounds, which is essential for CSF samples because abundance of these compounds in CSF is very low. The present study revealed potential interferences on the analysis of F2-IsoPs and F4-NPs in CSF by GC/NICI-MS due to the use of improper analytical methods that have been employed in the literature. First, simultaneous quantification of F2-IsoPs and F4-NPs in CSF samples processed for F4-NPs analysis could cause poor chromatographic separation and falsely higher F2-IsoPs values for CSF samples with high levels of F2-IsoPs and F4-NPs. Second, retention of unknown substances in GC columns from CSF samples during F4-NPs analysis and from plasma samples during F2-IsoPs analysis might interfere with F4-NPs analysis of subsequent runs, which could be solved by holding columns at a high temperature for a period of time after data acquisition. Therefore, these special issues should be taken into consideration when performing analysis of F2-IsoPs and F4-NPs in CSF to avoid misleading results.

Increase in cerebrospinal fluid F2-isoprostanes is related to cognitive decline in APOE ε4 carriers.

In this longitudinal study we investigated the effect of apolipoprotein E (APOE) genotype on the relation between cognitive decline and cerebrospinal fluid (CSF) F2-isoprostanes, the reference marker for oxidative stress. Twenty non-demented subjects, 58 mild cognitive impairment (MCI) patients, and 63 Alzheimer's disease (AD) patients with measurements of CSF F2-isoprostanes at two time points (with a mean interval of 2.0 ± 1.1 years) and known APOE genotype were included. Mean clinical follow-up time was 3.9 ± 2.4 years. For change in F2-isoprostanes over time and associations with Mini-Mental State Examination scores, age- and gender-adjusted linear mixed models were used. Analyses were done for APOE ε4 carriers and non-carriers separately. In APOE ε4 carriers, annual change in F2-isoprostane levels appeared larger than in APOE ε4 non-carriers (ß[SE] 2.5[0.5], p < 0.001 versus 1.8[0.5], p < 0.01). In addition, increase in F2-isoprostanes was associated with further cognitive decline in APOE ε4 carriers (p < 0.05), but not in non-carriers (p = 0.28). Our results reiterate the importance of oxidative stress in neurodegeneration, especially in APOE ε4 carrying patients. Future studies should focus on the possibility of increased vulnerability to oxidative damage in APOE ε4 carriers.

Lower CSF amyloid beta peptides and higher F2-isoprostanes in cognitively intact elderly individuals with major depressive disorder.

OBJECTIVE: Major depressive disorder is common in the elderly, and symptoms are often not responsive to conventional antidepressant treatment, especially in the long term. Soluble oligomeric and aggregated forms of amyloid beta peptides, especially amyloid beta 42, impair neuronal and synaptic function. Amyloid beta 42 is the main component of plaques and is implicated in Alzheimer's disease. Amyloid beta peptides also induce a depressive state in rodents and disrupt major neurotransmitter systems linked to depression. The authors assessed whether major depression was associated with CSF levels of amyloid beta, tau protein, and F2-isoprostanes in elderly individuals with major depressive disorder and age-matched nondepressed comparison subjects. METHOD: CSF was obtained from 47 cognitively intact volunteers (major depression group, N=28; comparison group, N=19) and analyzed for levels of soluble amyloid beta, total and phosphorylated tau proteins, and isoprostanes. RESULTS: Amyloid beta 42 levels were significantly lower in the major depression group relative to the comparison group, and amyloid beta 40 levels were lower but only approaching statistical significance. In contrast, isoprostane levels were higher in the major depression group. No differences were observed in total and phosphorylated tau proteins across conditions. Antidepressant use was not associated with differences in amyloid beta 42 levels. CONCLUSIONS: Reduction in CSF levels of amyloid beta 42 may be related to increased brain amyloid beta plaques or decreased soluble amyloid beta production in elderly individuals with major depression relative to nondepressed comparison subjects. These results may have implications for our understanding of the pathophysiology of major depression and for the development of treatment strategies.

Antioxidants for Alzheimer disease: a randomized clinical trial with cerebrospinal fluid biomarker measures.

OBJECTIVE: To evaluate whether antioxidant supplements presumed to target specific cellular compartments affected cerebrospinal fluid (CSF) biomarkers. DESIGN: Double-blind, placebo-controlled clinical trial. SETTING: Academic medical centers. PARTICIPANTS: Subjects with mild to moderate Alzheimer disease. INTERVENTION: Random assignment to treatment for 16 weeks with 800 IU/d of vitamin E (α-tocopherol) plus 500 mg/d of vitamin C plus 900 mg/d of α-lipoic acid (E/C/ALA); 400 mg of coenzyme Q 3 times/d; or placebo. MAIN OUTCOME MEASURES: Changes from baseline to 16 weeks in CSF biomarkers related to Alzheimer disease and oxidative stress, cognition (Mini-Mental State Examination), and function (Alzheimer's Disease Cooperative Study Activities of Daily Living Scale). RESULTS: Seventy-eight subjects were randomized; 66 provided serial CSF specimens adequate for biochemical analyses. Study drugs were well tolerated, but accelerated decline in Mini-Mental State Examination scores occurred in the E/C/ALA group, a potential safety concern. Changes in CSF Aß42, tau, and P-tau(181) levels did not differ between the 3 groups. Cerebrospinal fluid F2-isoprostane levels, an oxidative stress biomarker, decreased on average by 19% from baseline to week 16 in the E/C/ALA group but were unchanged in the other groups. CONCLUSIONS: Antioxidants did not influence CSF biomarkers related to amyloid or tau pathology. Lowering of CSF F2-isoprostane levels in the E/C/ALA group suggests reduction of oxidative stress in the brain. However, this treatment raised the caution of faster cognitive decline, which would need careful assessment if longer-term clinical trials are conducted. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00117403.

Increased cerebrospinal fluid F2-isoprostanes are associated with aging and latent Alzheimer's disease as identified by biomarkers.

Alzheimer's disease (AD) is a common age-related chronic illness with latent, prodrome, and fully symptomatic dementia stages. Increased free radical injury to regions of brain is one feature of prodrome and dementia stages of AD; however, it also is associated with advancing age. This raises the possibility that age-related free radical injury to brain might be caused in part or in full by latent AD. We quantified free radical injury in the central nervous system with cerebrospinal fluid (CSF) F(2)-isoprostanes (IsoPs) in 421 clinically normal individuals and observed a significant increase over the adult human lifespan (P < 0.001). Using CSF amyloid (A) ß(42) and tau, we defined normality using results from 28 clinically normal individuals <50 years old, and then stratified 74 clinically normal subjects ≥60 years into those with CSF that had normal CSF Aß(42) and tau (n = 37); abnormal CSF Aß(42) and tau, the biomarker signature of AD (n = 24); decreased Aß(42) only (n = 4); or increased tau only (n = 9). Increased CSF F(2)-IsoPs were present in clinically normal subjects with the biomarker signature of AD (P < 0.05) and those subjects with increased CSF tau (P < 0.001). Finally, we analyzed the relationship between age and CSF F(2)-IsoPs for those clinically normal adults with normal CSF (n = 37) and those with abnormal CSF Aß(42) and/or tau (n = 37); only those with normal CSF demonstrated a significant increase with age (P < 0.01). These results show that CSF F(2)-IsoPs increased across the human lifespan and that this age-related increase in free radical injury to brain persisted after culling those with laboratory evidence of latent AD.

Oxidative stress and amyloid-beta pathology in normal individuals with a maternal history of Alzheimer's.

BACKGROUND: Epidemiology and imaging studies showed that cognitively normal (NL) individuals with a maternal history (MH) of late-onset Alzheimer's disease (LOAD) might be at increased risk for Alzheimer's disease (AD) compared with NL with a paternal history (PH) and NL with a negative family history of LOAD (NH). With a panel of cerebrospinal fluid (CSF) markers, this study examined whether NL MH showed evidence for AD pathology compared with PH and NH. METHODS: Fifty-nine 40-80-year-old NL subjects were examined, including 23 MH and 14 PH whose parents had a clinician-certified diagnosis of LOAD and 22 NH. All subjects completed clinical neuropsychological examinations and a lumbar puncture to measure CSF levels of amyloid-beta (Aß(40), Aß(42), Aß(42/40)), total and hyperphosphorylated tau (T-Tau and P-Tau(231); markers of axonal degeneration and neurofibrillary tangles, respectively), and F2-isoprostanes (IsoP) (a marker of oxidative stress). RESULTS: Groups were comparable for demographic and neuropsychological measures. The MH subjects showed higher IsoP and reduced Aß(42/40) CSF levels compared with NH and with PH (p values ≤ .05), whereas no differences were found between NH and PH. No group differences were found for P-Tau(231) and T-Tau. The IsoP and Aß(42/40) levels were correlated only within the MH group (R² = .32, p = .005) and discriminated MH from the other subjects with 70% accuracy (relative risk = 3.7%, 95% confidence interval = 1.6-9.7, p < .001). Results remained significant controlling for age, gender, education, and apolipoprotein E genotype. CONCLUSIONS: Adult children of LOAD-affected mothers express a pathobiological phenotype characterized by Aß-associated oxidative stress consistent with AD, which might reflect increased risk for developing the disease.

[Influence of acupuncture on isoprostane in patients with Alzheimer's disease].

OBJECTIVE: To explore the clinical therapeutic effect of acupuncture on Alzheimer's disease (AD) and its mechanism. METHODS: Twenty patients with Alzheimer's disease were treated by acupuncture with reinforcing kidney and activating blood method for 12 weeks and Baihui (GV 20), Shenshu (BL 23), Xuehai (SP 10) and Geshu (BL 17) were selected. The clinical therapeutic effect were assessed by comparing the scores of Alzheimer's Disease Assessment Scale-Cognitive Section (ADAS-Cog) and 8-IPF2alpha concentration in cerebrospinal fluid, blood and urine before and after treatment were detected by using enzyme linked immunosorbent assay. RESULTS: After treatment, the effective rate was 90.0%. The score of ADAS-Cog was 35. 70 +/- 14. 70 before treatment and 31. 45 +/- 4. 08 after treatment, with a significant difference (P<0. 001). The concentration of 8-IPF2alpha in cerebrospinal fluid, blood and urine were all significantly decreased after treatment (all P<0.001). CONCLUSION: Acupuncture can improve the cognitive ability of AD patients and its possible mechanism may be relative to the decrease in lipid peroxidation in AD patients' brain.

Correlation of F4-neuroprostanes levels in cerebrospinal fluid with outcome of aneurysmal subarachnoid hemorrhage in humans.

Aneurysmal subarachnoid hemorrhage (aSAH) is one type of hemorrhagic stroke in humans. F(2)-isoprostanes (F(2)-IsoPs) and F(4)-neuroprostanes (F(4)-NPs), derived from arachidonic acid and docosahexaenoic acid (DHA), respectively, are specific markers of lipid peroxidation. We previously demonstrated that F(2)-IsoPs levels in cerebrospinal fluid (CSF) of aSAH patients positively correlated with poor clinical conditions. In this work, we refined F(4)-NPs analysis and investigated the role of potential oxidative damage to neurons in aSAH patients by detecting F(4)-NPs in CSF. [(2)H(4)]-15-F(2t)-IsoP, rather than [(18)O(2)]-17-F(4c)-NP or [(2)H(4)]-PGF(2 alpha), was used as the internal standard for F(4)-NPs analysis. One problem of the use of [(18)O(2)]-17-F(4c)-NP was the potential interference resulting from F(2)-dihomo-IsoPs in CSF. CSF specimens of 15 aSAH patients for up to 10 days and those of 12 non-aSAH controls were analyzed. First day, mean, and peak levels of F(4)-NPs were all significantly higher in aSAH patients than in controls and correlated with the Fisher Scale and 3-month Glasgow Outcome Scale, but only mean levels of F(4)-NPs correlated with Hunt and Hess Grade. The results first demonstrate oxidative damage to DHA in brain tissue following aSAH and suggest that F(4)-NPs in CSF could be a better predictor for outcome of aSAH than F(2)-IsoPs at early time points.

Elevated cerebrospinal fluid F2-isoprostane levels indicating oxidative stress in healthy siblings of multiple sclerosis patients.

Lipid peroxidation has been implicated in the pathogenesis of multiple sclerosis (MS). Isoprostanes, isomers of prostaglandins, are produced by free radical-mediated peroxidation of fatty acids in vivo and can be quantified in biological fluids. This study examines the levels of cerebrospinal fluid (CSF) F2-isoprostanes (F2-iPs) in MS patients (n=46), their healthy siblings (n=46) and unrelated controls (n=50). The median CSF F2-iP concentration (range) was significantly higher in siblings of MS patients, as compared to healthy controls (40.0 [7.1-68.7] and 29.1 [6.4-60.3] pg/mL, respectively, p=0.031). MS patients demonstrated F2-iP levels intermediate between siblings and controls. F2-iP levels in MS patients and siblings correlated significantly (R=0.360, p=0.012). These results suggest that siblings of MS patients have an increased oxidative stress response to environmental and/or genetic factors that may be involved in MS pathogenesis.

Effect of statins on Alzheimer's disease biomarkers in cerebrospinal fluid.

BACKGROUND: Treatment with HMG-CoA reductase inhibitors ("statins") has been variably associated with a reduced risk of Alzheimer's disease (AD) in epidemiologic studies and reduced amyloid-beta (Abeta) deposition in animal models of AD. Putative neuroprotective effects of statins may vary in relation to their ability to penetrate into the central nervous system (CNS). METHODS: We measured levels of cerebrospinal fluid (CSF) AD biomarkers following 14 weeks of treatment with simvastatin (a CNS permeant statin; n=10) at 40 mg/day or pravastatin (a CNS impermeant statin; n=13) at 80 mg/day in hypercholesterolemic subjects without dementia. RESULTS: Simvastatin, but not pravastatin, reduced CSF levels of phospho-tau-181 (p-tau181) in all subjects. There were no differences in CSF levels of total tau, Abeta42, Abeta40, soluble amyloid beta protein precursor (sAbetaPP) alpha or beta, or F2-isoprostanes. CONCLUSIONS: Statins may modulate the phosphorylation of tau in humans and this effect may depend on the CNS availability of the statin. These results suggest another mechanism by which statins may act to reduce the risk of AD.

Porous graphitic carbon chromatography-tandem mass spectrometry for the study of isoprostanes in human cerebrospinal fluid.

F2-isoprostanes are produced by the non-enzymatic peroxidation of arachidonic acid in membrane phospholipids. This paper describes a new method for the determination of all four classes of F2-isoprostanes in human cerebrospinal fluid (CSF) involving separation on a 1 mm x 150 mm porous graphitic carbon (PGC) column and detection by triple quadrupole mass spectrometry in negative-ion electrospray mode. The sample pre-treatment consisted of an ultrafiltration step, following which 300 microl of CSF sample could be injected directly onto a 1 mm x 10 mm PGC guard column functioning as a trap for the analytes. The loading solvent was Milli-Q water at 125 microl/min. After 3 min, the sample was switched into the separation column. The F2-isoprostanes were separated in 20 min using a linear solvent gradient comprising water, methanol, acetonitrile and ammonium hydroxide at a pH of 9.5 and a flow of 50 microl/min The limit of detection (calculated as 3S/N) was approximately 40 pM (14 pg/ml). The assay was linear within the examined range (18-450 pg/ml), using CSF spiked with iPF2alpha-III standard (r(2)>0.995). Repeatability data were calculated for CSF spiked to 90 pg/ml and the relative standard deviation (RSD) obtained was 3% (n=6).

Hyperinsulinemia provokes synchronous increases in central inflammation and beta-amyloid in normal adults.

BACKGROUND: Inflammation has been implicated as a pathogenetic factor in Alzheimer disease, possibly via effects on beta-amyloid (Abeta). Hyperinsulinemia induces inflammation and is a risk factor for Alzheimer disease. Thus, insulin abnormalities may contribute to Alzheimer disease pathophysiology through effects on the inflammatory network. OBJECTIVES: To determine the effects of induced hyperinsulinemia with euglycemia on Abeta, transthyretin, and inflammatory markers and modulators in plasma and cerebrospinal fluid (CSF). DESIGN: Randomized crossover trial. SETTING: Veterans Affairs hospital clinical research unit. PARTICIPANTS: Sixteen healthy adults ranging from 55 to 81 years of age (mean age, 68.2 years). INTERVENTIONS: On separate mornings, fasting participants received randomized infusions of saline or insulin (1.0 mU.kg(-1).min(-1)) with variable dextrose levels to maintain euglycemia, achieving plasma insulin levels typical of insulin resistance. Plasma and CSF were collected after an approximately 105-minute infusion. MAIN OUTCOME MEASURES: Plasma and CSF levels of interleukin 1alpha, interleukin 1beta, interleukin 6, tumor necrosis factor alpha, F2-isoprostane (CSF only), Abeta, norepinephrine, transthyretin, and apolipoprotein E. RESULTS: Insulin increased CSF levels of F2-isoprostane and cytokines (both P<.01), as well as plasma and CSF levels of Abeta42 (both P<.05). The changes in CSF levels of Abeta42 were predicted by increased F2-isoprostane and cytokine levels (both P<.01) and reduced transthyretin levels (P = .02). Increased inflammation was modulated by insulin-induced changes in CSF levels of norepinephrine and apolipoprotein E (both P<.05). CONCLUSION: Moderate hyperinsulinemia can elevate inflammatory markers and Abeta42 in the periphery and the brain, thereby potentially increasing the risk of Alzheimer disease.