Growth hormone and outcome in patients with intracerebral hemorrhage: a pilot study.

BACKGROUND: Endocrine alterations of the hypothalamic-pituitary-axis are one of the first measurable physiological changes in cerebral insults. During acute stress, human growth hormone (GH) is stimulated and has shown to have a prognostic value in various diseases. Within this pilot study, we evaluated the prognostic value of GH in patients with acute intracerebral hemorrhage (ICH). METHODS: In a prospective observational study in 40 consecutive patients with ICH, GH was measured on admission. The prognostic value of GH to predict 30-day mortality and 90-day functional outcome was assessed. Favorable functional outcome was defined as Barthel Index score >85 points and Modified Rankin Scale <3 points. RESULTS: GH levels were increased in patients who died within 30 days as compared to survivors (0.45 (IQR 0.20-1.51) vs. 1.51 (IQR 0.91-4.08) p = 0.03), and in patients with an unfavorable functional outcome as compared to patients with a favorable functional outcome after 90 days 0.28 (IQR 0.16-0.61) vs. 0.78 (IQR 0.31-1.99) p = 0.03). For mortality prediction, receiver-operating-characteristics revealed an area under the curve (AUC) on admission for GH of 0.78 (95% CI 0.60-0.96), which was in the range of the Glasgow Coma Score (GCS) (AUC 0.82 (95% CI 0.59-1.00) p = 0.80). For functional outcome prediction, GH had an AUC of 0.71 (95% CI 0.54-0.87), which was statistically not different from the GCS (AUC 0.81 (95% CI 0.68-0.94) p = 0.36). CONCLUSIONS: In our small cohort of patients with acute ICH, elevated GH level were associated with increased mortality and worse outcome. If confirmed in a larger study, GH levels may be used as an additional prognostic factor in ICH patients. (ClincalTrials.gov number NCT00390962).

Antihypertensive therapy is associated with reduced rate of conversion to Alzheimer's disease in midregional proatrial natriuretic peptide stratified subjects with mild cognitive impairment.

BACKGROUND: Hypertension is a major risk factor of Alzheimer's disease (AD); however, controlled studies on the effect of antihypertensive treatment on the risk of dementia are inconclusive. Therefore, a biological marker that predicts individual response to antihypertensive treatment would be of high clinical relevance. Midregional proatrial natriuretic peptide (MR-proANP), an inactive surrogate molecule of the mature atrial natriuretic peptide, is related to circulatory function and hypertension. METHODS: A sample population of 134 subjects with mild cognitive impairment (MCI) was followed for up to 6 years. Multivariable Cox regression analysis was conducted to predict conversion to AD based on all relevant variables. RESULTS: Baseline MR-proANP was significantly increased in the AD converter group (p < .0001). The conversion rate of patients treated with antihypertensive drugs was significantly reduced only in patients with elevated MR-proANP at baseline (p = .046). Using an optimized MR-proANP cutoff of 74 pmol/L, representing a value in the upper normal range, treatment with antihypertensive drugs reduced the conversion rate to AD by 36% (p = .035) for patients with levels >74 pmol/L. Further subgrouping by age (>/≤ 72 years at baseline) increased the positive correlation of antihypertensive treatment and MCI outcome for patients below the age of 72 years (conversion rate reduced by 74%, p = .016). CONCLUSIONS: These data seem to support the notion of a potential impact of circulatory function for the prognosis of AD at a prodromal stage. The MR-proANP levels may be useful to predict the effect of antihypertensive treatment on conversion rates to AD in subjects with MCI.

Prediction of Alzheimer's disease using midregional proadrenomedullin and midregional proatrial natriuretic peptide: a retrospective analysis of 134 patients with mild cognitive impairment.

OBJECTIVE: Development of biomarkers for early detection of Alzheimer's disease (AD) is a major clinical research goal. On the basis of the hypothesis that cardiovascular risk factors contribute to the pathogenesis of AD, we investigated whether the cardiovascular risk markers midregional proadrenomedullin (MR-proADM) and midregional proatrial natriuretic peptide (MR-proANP) predict a major clinical milestone, ie, conversion from predementia mild cognitive impairment (MCI) to manifest AD. METHOD: A group of 134 MCI patients, among 137 originally prospectively recruited at the memory disorder clinic at Malmö University Hospital, Malmö, Sweden, between July 1998 and June 2001, was clinically followed for 4-6 years. We determined whether plasma concentrations of MR-proADM and MR-proANP at baseline predicted time to conversion from MCI to clinically diagnosed AD (DSM-III-R). MCI was diagnosed according to Petersen criteria. RESULTS: During follow-up, 41.8% of MCI patients remained cognitively stable, 42.5% converted to possible and probable AD, and 15.7% converted to other forms of dementia (MCI-other). MCI converters and MCI-other patients showed increased concentrations of MR-proANP and MR-proADM compared to the stable MCI patients (P = .0001). At a cutoff of 87 pmol/L, MR-proANP yielded a sensitivity of 73.7% and a specificity of 64.3% for predicting conversion to AD. The survival analysis showed that higher values of MR-proANP and MR-proADM were associated with progression to AD. In a multivariate Cox regression model including known risk factors, MR-proANP and MR-proADM remained independent risk factors for conversion to AD for patients below the age of 72 years. CONCLUSIONS: Our study shows that plasma concentrations of MR-proANP and MR-proADM have predictive value in the progression from predementia MCI to clinical AD. Sensitivity was particularly high, which may recommend this test for first-stage screening in patients at risk for AD.

Midregional Proenkephalin A and N-terminal Protachykinin A are decreased in the cerebrospinal fluid of patients with dementia disorders and acute neuroinflammation.

Midregional Proenkephalin A (MR-PENK A) and N-terminal Protachykinin A (NT-PTA) are stable fragments of the precursor peptides for enkephalins and substance P, respectively. We measured MR-PENK A and NT-PTA concentrations by sensitive chemiluminescence immunoassays in cerebrospinal fluid (CSF) of 19 neurologically healthy controls (NHC), 28 patients with other neurologic disorders (OND), 70 patients with dementia disorders (38 Alzheimer's disease [AD], 8 dementia with Lewy bodies [DLB], 12 frontotemporal dementia [FTD], and 12 patients with vascular dementia [VD]), and 16 patients with acute neuroinflammation (AN). Median concentrations of NT-PTA were decreased in all patient groups compared to NHC showing significant differences between patients with NHC and AN (p<0.001), OND and AN (p<0.001), FTD and AN (p<0.01) and pAD and AN (p<0.05). Median MR-PENK A levels were lower in patients with OND, dementia disorders (including AD, FTD, DLB and VD) and AN compared to NHC subjects, although this differences did not reach statistical significance (p>0.05). A maximum difference of both proneuropeptide fragments was found between NHC subjects and patients with AN, with a more than 2fold decrease in median NT-PTA and a 1.5fold decrease in median MR-PENK A levels. Concentrations of both proneuropeptide fragments were positively correlated in all patients (r=0.77, p<0.001). Our results indicate alterations of the cerebral PENK A- and PTA-system in both, dementia and acute neuroinflammatory disorders. These neuropeptide systems seem to be highly correlated in healthy and pathological status.

Cisterna chyli in patients with malignancy--is there a correlation between changes in cisterna volume and progression or regression of the tumor?

UNLABELLED: The purpose of this study was to investigate the potential correlation between the size of the cisterna chyli (CC) and the tumor size in patients with malignancies on computed tomography (CT). MATERIALS AND METHODS: Out of a 3000 patient cohort 138 patients with histologically confirmed malignant disease, a detectable CC on CT and at least two CT scans within a 6 month period were included in this retrospective study. Out of 525 scans a total of 711 lesion intervals were evaluated. The volume of the CC and all target lesions (up to three per scan) were recorded. The Pearson correlation coefficient for the two parameters of changes in lesion size and CC size was calculated for the whole cohort and for a 33 patient subgroup that included only patients with tumors that showed the closest association with large CC in a previous study. RESULTS: The mean difference in lesion size for all 711 intervals was -1165µl. The mean difference in CC size for all 711 intervals was -46.6µl. The respective Pearson correlation coefficient was .05 with a non-significant p-value of .1823 (subgroup: r=.04, p=.6358). CONCLUSION: No significant correlation between the progression or regression of malignant disease and the size of the cisterna chyli could be found.

Pitfalls in abdominal diffusion-weighted imaging: how predictive is restricted water diffusion for malignancy.

OBJECTIVE: As diffusion-weighted imaging is increasingly implemented into routine protocols of abdominal MRI, abnormal findings in expected and unexpected locations become more common. The aim of our retrospective study was to investigate the specificity of restricted diffusion in differentiation of benign from malignant abdominal disease. MATERIALS AND METHODS: Two hundred thirty consecutively registered patients underwent abdominal MRI including diffusion-weighted imaging (single-shot spin-echo echo-planar sequence) with b values of 0, 150, 500, and 1,000 s/mm(2). Lesions were detected by two blinded readers using only the images with a b value of 1,000 s/mm(2), and representative apparent diffusion coefficients were measured. Lymph nodes were not documented. RESULTS: Fifty-two of the 230 patients had a total of 55 lesions with restricted diffusion (23.9%). The mean apparent diffusion coefficient was 809 mm(2)/s. Forty-three lesions (78.2%) were malignant. The 12 benign lesions were liver hemangioma, liver adenoma, autoimmune pancreatitis, pancreatic teratoma, two abscesses, three cases of inflammatory bowel wall thickening due to Crohn's disease, Bartholin cyst, hemorrhagic ovarian cyst, and renal Rosai-Dorfman disease. CONCLUSION: Restricted diffusion is generally considered to be associated with malignant tumors because of the high cellularity of these tumors. However, in interpretation of diffusion-weighted images, it should be kept in mind that a number of benign lesions, as many as 22% in our cohort, can exhibit restricted diffusion on images with high b values, thus mimicking malignant lesions.

Blood-based microcirculation markers in Alzheimer's disease-diagnostic value of midregional pro-atrial natriuretic peptide/C-terminal endothelin-1 precursor fragment ratio.

BACKGROUND: There is evidence that vascular factors contribute substantially to Alzheimer's disease (AD). We have developed assays to reliably detect the circulation and microcirculation regulating factors C-terminal endothelin-1 precursor fragment (CT-proET-1), midregional pro-adrenomedullin (MR-proADM), and midregional pro-atrial natriuretic peptide (MR-proANP). We hypothesized that this set of blood-based (micro)circulation parameters is altered in AD. METHODS: Prospectively recruited volunteer cohort (94 patients with probable AD, 53 healthy control subjects [HC]). In plasma, CT-proET-1, MR-proADM, and MR-proANP were analyzed using sandwich luminescence immunoassays. Concentrations of plasma markers and their ratios (MR-proANP/CT-proET-1 and MR-proADM/CT-proET-1) were compared between groups. Diagnostic accuracy of the vasodilator/vasoconstrictor ratios were calculated in the training set (half of AD and HC groups, respectively) and the optimal cutoff was then applied to the test set (remaining half of the study population). RESULTS: In AD patients, concentrations of MR-proADM and MR-proANP were significantly increased and levels of CT-proET-1 were significantly decreased compared with HC subjects. The ratios MR-proANP/CT-proET-1 and MR-proADM/CT-proET-1 improved group separation compared with the single markers. In a logistic regression analysis, the ratios of vasodilator/vasoconstrictor significantly contributed to group separation. The highest diagnostic accuracy was found for the MR-proANP/CT-proET-1 ratio. When applied to the training (test) set, specificity was 82% (80) and sensitivity was 81% (72). CONCLUSIONS: This indicates altered expression of microcirculation parameters and supports the hypothesis of a disturbed microvascular homeostasis in AD. We generated the hypothesis that the vasodilator/vasoconstrictor ratios hold promise as a diagnostic marker of AD. The best diagnostic accuracy was achieved for the MR-proANP/CT-proET-1 ratio.

High-sensitivity chemiluminescence immunoassays for detection of growth hormone doping in sports.

BACKGROUND: Recombinant human growth hormone (rhGH) is abused in sports, but adequate routine doping tests are lacking. Analysis of serum hGH isoform composition has been shown to be effective in detecting rhGH doping. We developed and validated selective immunoassays for isoform analysis with potential utility for screening and confirmation in doping tests. METHODS: Monoclonal antibodies with preference for pituitary hGH (phGH) or rhGH were used to establish 2 pairs of sandwich-type chemiluminescence assays with differential recognition of rhGH (recA and recB) and phGH (pitA and pitB). We analyzed specimens from volunteers before and after administration of rhGH and calculated ratios between the respective rec- and pit-assay results. RESULTS: Functional sensitivities were <0.05 microg/L, with intra- and interassay imprecision < or =8.4% and < or =13.7%, respectively. In 2 independent cohorts of healthy subjects, rec/pit ratios (median range) were 0.84 (0.09-1.32)/0.81 (0.27-1.21) (recA/pitA) and 0.68 (0.08-1.20)/0.80 (0.25-1.36) (recB/pitB), with no sex difference. In 20 recreational athletes, ratios (median SD) increased after a single injection of rhGH, reaching 350% (73%) (recA/pitA) and 400% (93%) (recB/pitB) of baseline ratios. At a moderate dose (0.033 mg/kg), mean recA/pitA and recB/pitB ratios remained significantly increased for 18 h (men) and 26 h (women). After high-dose rhGH (0.083 mg/kg), mean rec/pit ratios remained increased for 32 h (recA/pitA) and 34 h (recB/pitB) in men and were still increased after 36 h in women. CONCLUSIONS: Using sensitive chemiluminescence assays with preferential recognition of phGH or rhGH, detection of a single injection of rhGH was possible for up to 36 h.

Electronic colon-cleansing for CT colonography: diagnostic performance.

BACKGROUND: The purpose of this study was to evaluate whether an electronic-colonic-cleansing (ECC) algorithm is beneficial for the diagnostic performance compared to a CT colonography (CTC) evaluation without electronic cleansing in tagged datasets. METHODS: Two blinded readers evaluated CTC datasets from 79 patients with 153 colorectal polyps confirmed by optical colonoscopy. Cases were read in a randomized order with and without the use of electronic colon-cleansing software. Per-polyp sensitivity, per-polyp/per-patient specificity and reading times (with and without ECC) have been calculated and reported. RESULTS: Per-polyp sensitivity for polyps >6 mm without using ECC was 60.4% (Reader 1: 59.7%, Reader 2: 61.1%), while polyps >10 mm were detected with a sensitivity of 58.3% (Reader 1: 66.7%, Reader 2: 50%). On electronically cleansed datasets, the sensitivity was 73.6% (Reader 1: 76.4%; Reader 2: 70.8%) for polyps >6 mm and 83.3% (Reader 1: 83.3%; Reader 2: 83.3%), respectively. Per-patient specificity was 75% without using cleansing (Reader 1: 68%, Reader 2: 82%) and 81.5% using ECC (Reader 1: 86%, Reader 2: 77%). CONCLUSION: Reading CTC cases using ECC software improves sensitivity in detecting clinically relevant colorectal polyps.

Detection of stable N-terminal protachykinin A immunoreactivity in human plasma and cerebrospinal fluid.

Substance P (SP) is a neuropeptide that is released from sensory nerves and several types of immune cells. It is involved in the transmission of pain and has a number of pro-inflammatory effects. Like other neuropeptides, SP is derived from a large precursor peptide, protachykinin A (PTA). Alternative splicing results in the production of four distinct PTA molecules that all contain the sequence of SP and a common N-terminal region consisting of 37 amino acids. We have developed a sandwich immunoassay using antibodies against the N-terminal part of PTA. Here we demonstrate that N-terminal PTA immunoreactivity is present in human circulation and cerebrospinal fluid (CSF). The concentration was about 90 times higher in CSF than in EDTA-plasma. Analytical reversed phase HPLC revealed that NT-PTA 1-37 is the main immunoreactivity in human circulation and CSF. Moreover, compared to the low in vitro stability of SP of less than 12 min, NT-PTA immunoreactivity is absolutely stable in EDTA-plasma and CSF for more than 48 h. As NT-PTA 1-37 is produced in stoichiometric amounts and is theoretically co-released with SP, we suggest the measurement of NT-PTA immunoreactivity as surrogate molecule for the release of bioactive SP.

Computer-aided detection in computer tomography colonography: a review.

BACKGROUND: Colorectal cancer is one of the most common causes of death from cancer. Computer tomography colonography (CTC) - also known as 'virtual colonoscopy' - is a minimally invasive, CT-based procedure that can simulate conventional colonoscopy using three-dimensional computerized reconstructions. In an attempt to improve the method further, a lot of research emphasis has been put on computer-aided detection (CAD) to overcome potential limitations of this examination. OBJECTIVE: This review recapitulates basic principles of CTC and CAD and highlights the importance of this method as a tool for screening for colorectal cancer. METHODS: This article reviews the current literature on CAD used with CT colonography. RESULTS/CONCLUSION: CAD potentially helps to improve the detection rate for adenomas, decrease interobserver variability and data set interpretation time.

Monitoring gastric filling, satiety and gastric emptying in a patient with gastric balloon using functional magnetic resonance imaging-a feasibility report.

BACKGROUND: Intragastric balloons are used for short term weight loss therapy in obese. It is possible to monitor the ballon with sonography, however this method is sometimes insufficient in obese patients. Therefore MRI seems to be a potential therapy-monitoring option. PURPOSE: In this feasibility report we want to demonstrate the potential use of functional MRI in monitoring gastric filling, patient satiation and gastric emptying in a obese patient who previously received intragastric balloon placement. MATERIAL AND METHODS: We selected one patient (male, 178 cm, 127 kg, BMI = 40,5 kg/m(2)) who recently received a gastric balloon and visualized gastric motility in presence of the gastric balloon before and after food intake. Fast cross-sectional images in one breathhold spin echo or gradient echo sequences were aquired. Real-time gastric motion was performed with cine mode. RESULTS: MRI offers perfect visualisation of gastric balloons in obese patients. Gastric filling and emptying can be monitored in correlation to patient satiety sensation. MRI can visualize the gastric balloon with degree of filling and possible leakages. Cine mode sequences demonstrate gastric motility and gastric wall peristalsis. CONCLUSION: MR is a valuable imaging alternative for patients with intragastric balloons.

CT colonography: an update.

Computed tomographic (CT) colonography (CTC)--also known as "virtual colonoscopy"--was first described more than a decade ago. As advancements in scanner technology and three-dimensional (3D) postprocessing helped develop this method to mature into a potential option in screening for colorectal cancer, the fundamentals of the examination remained the same. It is a minimally invasive, CT-based procedure that simulates conventional colonoscopy using 2D and 3D computerized reconstructions. The primary aim of CTC is the detection of colorectal polyps and carcinomas. However, studies reveal a wide performance variety in regard to polyp detection, especially for smaller polyps. This article reviews the available literature, discusses established indications as well as open issues and highlights potential future developments of CTC.

Procalcitonin is elevated in the cerebrospinal fluid of patients with dementia and acute neuroinflammation.

Procalcitonin (PCT) is an established marker for severe systemic bacterial infection and sepsis in blood. Here we measured PCT by immunoassay in CSF and matched serum/plasma samples of controls and patients with different primary dementia disorders and acute neuroinflammation. PCT in CSF was significantly increased in patients with probable Alzheimer's disease, vascular dementia, dementia with Lewy bodies, frontotemporal dementia and acute neuroinflammation (encephalitis, meningitis) compared to non-demented controls. In contrast, PCT levels in matched plasma samples were normal in dementia groups, but elevated in meningitis/encephalitis. Our results indicate a central production of PCT and suggest PCT as a valuable marker candidate for the monitoring of dementia and acute neuroinflammation.

Midregional proadrenomedullin reflects cardiac dysfunction in haemodialysis patients with cardiovascular disease.

BACKGROUND: Although adrenomedullin is an indicator of cardiac dysfunction in haemodialysis patients, the clinical significance of midregional proadrenomedullin has not been elucidated. Objectives. We evaluated whether midregional proadrenomedullin reflects cardiac dysfunction, systemic inflammation or blood volume in haemodialysis patients. METHODS: Plasma midregional proadrenomedullin, C-reactive protein and delta body weight (indicating excessive blood volume), and two-dimensional as well as Doppler echocardiographic variables were measured just before haemodialysis in 70 patients with cardiovascular disease. RESULTS: The median value of midregional proadrenomedullin was 1.93 nmol/l before haemodialysis, and these levels were significantly reduced following haemodialysis. Log [midregional proadrenomedullin] was positively correlated with left ventricular end-systolic volume index, diameter of inferior vena cava, C-reactive protein and delta body weight (r = 0.328, r = 0.421, r = 0.356, r = 0.364), and negatively with blood pressure, deceleration time of an early diastolic filling wave, pulmonary venous flow velocity ratio and left ventricular ejection fraction (r = -0.330, r = -0.324, r = -0.479, r = -0.373). Multivariate regression analysis revealed that pulmonary venous flow velocity ratio, diameter of inferior vena cava and C-reactive protein were independently related factors for midregional proadrenomedullin concentration. CONCLUSION: Plasma midregional proadrenomedullin levels increase in association with cardiac dysfunction, systemic inflammatory status and systemic blood volume in haemodialysis patients with concomitant cardiovascular disease.

Effect of gastric bypass and gastric banding on proneurotensin levels in morbidly obese patients.

CONTEXT: Neurotensin is produced mainly in the N cells of the ileum and has a role in appetite regulation; levels are decreased in obese subjects and increase after bariatric surgery. Mature neurotensin is very unstable, with a short half-life. OBJECTIVE: The objective of this study was to compare baseline and postoperative levels of the more stable neurotensin precursor, proneurotensin/neuromedin (pro-NT/NMN), in patients after gastric banding, gastric bypass, and nonoperated controls, respectively, during long-term follow-up. DESIGN AND SETTING: This was a prospective observational study in a university hospital. PARTICIPANTS AND MAIN OUTCOME MEASURES: Overnight fasting plasma pro-NT/NMN concentrations were measured with a new sandwich immunoassay in morbidly obese subjects at baseline and 6, 12, and 24 months after gastric banding (n = 8), Roux-en-Y gastric bypass (n = 5), and in nonoperated controls (n = 7). RESULTS: After gastric bypass and banding, body weight decreased by (mean +/- sd) 29.5 +/- 5.5 and 22.8 +/- 5.9 kg, respectively. The decrease after 3 and 6 months was more pronounced after gastric bypass compared with gastric banding (P < 0.05). Plasma pro-NT/NMN levels in patients after gastric bypass increased from 246.3 +/- 174.3 pmol/liter on admission to 748.3 +/- 429.6 pmol/liter after 24 months (P < 0.01). In contrast, in patients with gastric banding, pro-NT/NMN concentrations remained stable (207.3 +/- 60.5 pmol/liter at admission, 226.6 +/- 116.8 pmol/liter after 24 months). Neither body weight nor plasma pro-NT/NMN levels changed in nonoperated controls. CONCLUSION: Plasma pro-NT/NMN levels show a more pronounced increase after gastric bypass compared with gastric banding, suggesting that specific bariatric surgical procedures result in distinct alterations of gastrointestinal hormone metabolism. The more stable precursor pro-NT/NMN provides a new tool to quantify neurotensin levels in clinical practice.

Protein oxidation and the degradation of oxidized proteins in the rat oligodendrocyte cell line OLN 93-antioxidative effect of the intracellular spin trapping agent PBN.

Oligodendrocytes are the myelin-producing cells in the central nervous system. It was proposed that these cells are much more prone to oxidative damage than to other cells of the central nervous system. This fact seems to be due to their high iron store and low antioxidative defense mechanisms. Consequently, free radical induced damage should lead to an enhanced damage of oligodendrocytes. Thus, we chose the oligodendrocyte cell line OLN 93 to measure the stability of the protein pool after oxidation and the possibilities of protecting proteins by alpha-phenyl-N-tert-butylnitrone (PBN). We were able to demonstrate for the first time that OLN 93 cells are able to respond with an increase in overall proteolysis when exposed to various oxidants. This increase was the consequence of an enhanced protein oxidation. The activity of the 20S proteasome, which is thought to be involved in the removal of oxidized proteins, was not effected by moderate concentrations of the oxidants. The spin-trap PBN was used as an antioxidant and was able to prevent protein oxidation in OLN 93 cells effectively. Consequently, we proved that PBN is also able to prevent the increase in overall protein oxidation. We were able to demonstrate that OLN 93 oligodendrocytes react to oxidative stress with an increase in the protein turnover directed towards the removal of oxidized proteins. The intracellular spin-trap PBN is able to prevent protein oxidation in OLN 93 cells.

Antioxidants effectively prevent oxidation-induced protein damage in OLN 93 cells.

Oxidative stress is supposed to play an important role in demyelinating diseases. Oligodendrocytes are the myelin-forming cells in the brain and are highly susceptible to oxidative stress due to their low antioxidative defense systems and high metabolic rate. In the present work, we tested the response of the oligodendrocyte cell line OLN 93 to oxidative stress. OLN 93 cell cultures are characterized by a loss of cell viability after oxidation. This loss of cell viability is accompanied by an increase in protein oxidation and consequently an elevated overall proteolysis. To minimize the oxidative damage, we tested the effects of the antioxidants alpha-lipoic acid and coenzyme Q(10). Both compounds were able to elevate cell viability and to decrease intracellular protein turnover and oxidant induced protein oxidation. Therefore, we concluded that the excessive oxidative damage of oligodendrocytes and their protein pool can be prevented by the usage of antioxidants.