Elżbieta Miller

Oxidative modification of patient's plasma proteins and its role in pathogenesis of multiple sclerosis

BACKGROUND Oxidative stress plays an important role in multiple sclerosis (MS). OBJECTIVE AND METHODS The present study was designed to evaluate the modifications of plasma proteins by estimation markers of oxidative/nitrosative stress: carbonyl groups and 3-nitrotyrosines (3-NT) levels in relapsing-remitting (RR) (n=10) and secondary progressive (SP) (n=10) clinical course of multiple sclerosis. Moreover, we estimated the level of uric acid (UA) in plasma of MS patients. RESULTS Compared to controls (n=10), the levels of carbonyl groups in plasma proteins were elevated (P<0.0001) as well in RRMS as in SPMS. The highest concentration of 3-NT was observed in plasma proteins obtained from SPMS patients (P<0.0005). The level of uric acid in plasma was significantly lower in RRMS (P<0.0001) than SPMS. CONCLUSION This is the first report which presented differences between SPMS and RRMS patients in 3-NT and protein carbonyl groups in plasma proteins.

Melatonin Redox Activity. Its Potential Clinical Applications in Neurodegenerative Disorders

Neurodegeneration is the hallmark of many chronic progressive neurogical disorders characterized by specific clinical, morphological and biochemical features. Central nervous system is very sensitive to oxidative stress, which is considered as a key factor of neurodegenerative disorders. Therefore, many therapeutical strategies are focused on molecules with redox activity to re-establish the equilibrium between pro and antioxidants. Due to the fact that melatonin readily crosses the blood- brain-barrier, concomitant with its safety profile at the highest dosages makes this dietary supplement very useful in possible clinical application in neurodegeneration. Melatonin is currently marketed in several countries as a dietary supplement with no prescription. Clinical trials have shown different effectiveness of melatonin supplementation in several disorders, including neurodegenerative disorders. Melatonin has unique biochemical properties such as scavenging of hydroxyl, carbonate, alkoxyl, peroxyl and aryl cation radicals and stimulation of activities main antioxidative enzymes (glutathione peroxidase, superoxide dismutase etc.). Moreover, it can suppress nitric oxide synthase. The present paper highlighted the potential clinical role of melatonin in main neurodegenerative diseases including Alzheimer disease, Parkinson disease, amylotrophic lateral sclerosis and multiple sclerosis. Moreover, in this review the main molecular aspects of melatonin in brain cell protection and survival mechanisms were discussed. Therefore, melatonin is regarded as a potential therapeutical agent in clinical application in neurodegenerative disorders, but this findings needs to be confirmed by the larger, more well-designed clinical trials.

Isoprostanes and Neuroprostanes as Biomarkers of Oxidative Stress in Neurodegenerative Diseases

Accumulating data shows that oxidative stress plays a crucial role in neurodegenerative disorders. The literature data indicate that in vivo or postmortem cerebrospinal fluid and brain tissue levels of F2-isoprostanes (F2-IsoPs) especially F4-neuroprotanes (F4-NPs) are significantly increased in some neurodegenerative diseases: multiple sclerosis, Alzheimers disease, Huntingtons disease, and Creutzfeldt-Jakob disease. Central nervous system is the most metabolically active organ of the body characterized by high requirement for oxygen and relatively low antioxidative activity, what makes neurons and glia highly susceptible to destruction by reactive oxygen/nitrogen species and neurodegeneration. The discovery of F2-IsoPs and F4-NPs as markers of lipid peroxidation caused by the free radicals has opened up new areas of investigation regarding the role of oxidative stress in the pathogenesis of human neurodegenerative diseases. This review focuses on the relationship between F2-IsoPs and F4-NPs as biomarkers of oxidative stress and neurodegenerative diseases. We summarize the knowledge of these novel biomarkers of oxidative stress and the advantages of monitoring their formation to better define the involvement of oxidative stress in neurological diseases.

Melatonin reduces oxidative stress in the erythrocytes of multiple sclerosis patients with secondary progressive clinical course

Oxidative stress plays a major role in multiple sclerosis (MS). Melatonin is a potent neuroprotectant. The aims of this study were to determine the actions of melatonin in the reduction of oxidative stress in MS. Therefore, we estimated lipid peroxidation and activities of main antioxidative enzymes in the red blood cells (RBCs) from selective group of MS patients only with secondary progressive (SPMS) clinical form and verified results with functional state. The sixteen (n=16) SPMS patients were supplemented with melatonin (10 mg daily/30 days). Age matched healthy subjects were used as a control (n=13). We determined the level of lipid peroxidation by malondialdehyde (MDA) and activities of main antioxidative enzymes: superoxide dismutase (SOD), catalase (CAT) and glutathione peroxide (GPx) in RBCs of SPMS patients. Melatonin caused statistically significant increase of SOD, GPx (p<0.0001 and p=0.004065, respectively) and decrease of MDA in erythrocytes of SPMS patients (p=0.00019). Correlation analysis of Spearman showed positive correlation between SOD and (expanded disability status scale) EDSS scale both before (r=0.64, p=0.00756) and after (r=0.634, p=0.00834) melatonin treatment. These results demonstrate that supplementation with melatonin SPMS patients should be taken into account, especially in progressive form of MS.

Effects of whole-body cryotherapy on a total antioxidative status and activities of antioxidative enzymes in blood of depressive multiple sclerosis patients.

Abstract Objectives. Oxidative stress (OS) plays an important role in the pathogenesis of multiple sclerosis (MS). In MS patients depression is often observed. Cryotherapy might have an effect on OS. The aim of this study was to compare the effects of whole body cryotherapy (WBCT) on changes in total antioxidative status (TAS) of plasma and activities of antioxidative enzymes in erythrocytes from depressive and non depressive MS patients. Methods. Twenty-two MS patients with secondary progressive disease course (12 depressive and 10 non depressive) were treated with 10 exposures in a cryochamber. Before and after WBCT the plasma TAS and the activities of superoxide dismutase (SOD) and catalase (CAT) in the erythrocytes were measured. Results. The level of TAS in depressive MS group was significantly lower than in non depressive MS (P < 0.0003). WBCT increased the level of TAS in depressive (P < 0.002) more than in non depressive MS patients (P < 0.01). WBCT treatment of MS patients resulted in the significant increase of TAS level in plasma but had no effects on activities of SOD and CAT. Conclusions. Our results indicate that WBCT suppresses OS in MS patients, especially in depressive patients.

Poststroke Depression as a Factor Adversely Affecting the Level of Oxidative Damage to Plasma Proteins during a Brain Stroke

Poststroke depression, the second most serious psychosomatic complication after brain stroke, leads to delay of the rehabilitation process and is associated with an increased disability and cognitive impairment along with increase in term mortality. Research into the biochemical changes in depression is still insufficiently described. The aim of our study was therefore to evaluate the possible association between plasma protein oxidative/nitrative damages and the development of poststroke depression. We evaluated oxidative/nitrative modifications of specific proteins by measurement of 3-nitrotyrosine and carbonyl groups levels using ELISA test. Additionally, we checked differences in proteins thiol groups by spectrophotometric assay based on reaction between DTNB and thiols. We also evaluated catalase activity in erythrocytes measured as ability to decompose H2O2. Correlation analysis was performed using Spearmans rank. We observed significant (P < 0.001) differences in all oxidative/nitrative stress parameters in brain stroke patients compared to healthy group. Our research shows that oxidative damage of proteins is correlated with the degree of poststroke depression, while nitrative changes do not show any relationship. We demonstrate a positive correlation between the concentration of carbonyl groups and the Geriatric Depression Scale and a negative correlation between the degree of depression and the concentration of -SH groups or catalase activity.

Whole-body cryostimulation (cryotherapy) provides benefits for fatigue and functional status in multiple sclerosis patients. A case-control study.

To study the effects of whole‐body cryostimulation (WBC) on fatigue and functional status in multiple sclerosis (MS) patients with different levels of fatigue.

Long-term effects of whole body cryostimulation on uric acid concentration in plasma of secondary progressive multiple sclerosis patients.

Abstract Background. Uric acid (UA) has been suggested to be a marker of multiple sclerosis (MS) activity. Whole body cryostimulation (WBCT) is a new form of additional treatment and becoming popular in medicine. Objectives. The aims of this study were to determine the long-term effects of WBCT on the level of plasma UA in selected group of MS patients only with secondary progressive (SPMS) clinical form and verify results with functional state of patients assessed by expanded disability status scale (EDSS). Materials and methods. SPMS patients (n = 22) and healthy controls (n = 22) participated in 10 3-min-long exposures of WBCT (one exposure per day). Results were collected before the WBCT treatment and after completion the WBCT series as well as one and three months later. Results. WBCT increased UA concentration in plasma of SPMS patients not only directly after 10 exposures (p < 0.0001) but also one (p < 0.0001) and three (p < 0.005) months later. Furthermore, WBCT causes positive changes in EDSS scale both directly after WBCT (7% lower) and maintain this level 1month later as well as 3 month later (5% lower). Conclusions. WBCT may be used as adjuvant therapy via increase UA blood level; it improves functional status of SPMS patients.

Relationship between the Increased Haemostatic Properties of Blood Platelets and Oxidative Stress Level in Multiple Sclerosis Patients with the Secondary Progressive Stage.

Multiple sclerosis (MS) is the autoimmune disease of the central nervous system with complex pathogenesis, different clinical courses and recurrent neurological relapses and/or progression. Despite various scientific papers that focused on early stage of MS, our study targets selective group of late stage secondary progressive MS patients. The presented work is concerned with the reactivity of blood platelets in primary hemostasis in SP MS patients. 50 SP MS patients and 50 healthy volunteers (never diagnosed with MS or other chronic diseases) were examined to evaluate the biological activity of blood platelets (adhesion, aggregation), especially their response to the most important physiological agonists (thrombin, ADP, and collagen) and the effect of oxidative stress on platelet activity. We found that the blood platelets from SP MS patients were significantly more sensitive to all used agonists in comparison with control group. Moreover, the platelet hemostatic function was advanced in patients suffering from SP MS and positively correlated with increased production of O2 −∙ in these cells, as well as with Expanded Disability Status Scale. We postulate that the increased oxidative stress in blood platelets in SP MS may be primarily responsible for the altered haemostatic properties of blood platelets.

Flow cytometric analysis reveals the high levels of platelet activation parameters in circulation of multiple sclerosis patients

The epidemiological studies confirm an increased risk of cardiovascular disease in multiple sclerosis, especially prothrombotic events directly associated with abnormal platelet activity. The aim of our study was to investigate the level of blood platelet activation in the circulation of patients with chronic phase of multiple sclerosis (SP MS) and their reactivity in response to typical platelets’ physiological agonists. We examined 85 SP MS patients diagnosed according to the revised McDonald’s criteria and 50 healthy volunteers as a control group. The platelet activation and reactivity were assessed using flow cytometry analysis of the following: P-selectin expression (CD62P), activation of GP IIb/IIIa complex (PAC-1 binding), and formation of platelet microparticles (PMPs) and platelet aggregates (PA) in agonist-stimulated (ADP, collagen) and unstimulated whole blood samples. Furthermore, we measured the level of soluble P-selectin (sP-selectin) in plasma using ELISA method, to evaluate the in vivo level of platelet activation, both in healthy and SP MS subjects. We found a statistically significant increase in P-selectin expression, GP IIb/IIIa activation, and formation of PMPs and PA, as well as in unstimulated and agonist-stimulated (ADP, collagen) platelets in whole blood samples from patients with SP MS in comparison to the control group. We also determined the higher sP-selectin level in plasma of SP MS subjects than in the control group. Based on the obtained results, we might conclude that during the course of SP MS platelets are chronically activated and display hyperreactivity to physiological agonists, such as ADP or collagen.