Slobodan Vojinovic

The glutathione S-transferase T1 deletion is associated with susceptibility to multiple sclerosis

BACKGROUND Multiple sclerosis (MS) occurs as a result of interaction between genetic and environmental factors. Recent data support the view that oxidative damage is one of an early event in MS tissue injury. The safe elimination of reactive oxygen species and toxins via glutathione S-transferase (GST) pathways is required in order to protect cells against reactive oxygen-induced damage. The aim of our study was to analyze the possible association of GSTM1 and GSTT1 gene polymorphisms with the susceptibility and clinical parameters of MS, in 455 consecutive patients and 366 controls. METHODS A multiplex polymerase chain reaction (PCR) was used to detect the deletions in GSTM1 and GSTT1 genes. RESULTS Patients with MS had significantly higher frequency of GSTT1 null genotype compared to controls (37.36% vs. 21.86%, respectively, p<0.0001, adjusted OR 2.13 (1.56-2.90)), as well as double deletions (15.38% vs. 10.38%, respectively, p<0.05). The carriers of GSTM1 deletion had significantly earlier onset of MS compared to the wild-type carriers (28.31 ± 8.45 vs. 30.64 ± 9.30 years, respectively, p = 0.03). CONCLUSION This study suggests the potential pathogenic role of GSTT1 deletion on MS susceptibility. There are no similar data published so far, yet this study should be replicated in other populations.

INF-β1b therapy modulates L-arginine and nitric oxide metabolism in patients with relapse remittent multiple sclerosis.

OBJECTIVE The scope of this study is the examination of NO(2)+NO(3), 3-nitrotyrosine (3-NT), S-nitrosothiols (RSNO), arginase activity and asymmetric (ADMA) and symmetric (SDMA) dimethyl-L-arginine concentrations in plasma of MS patients during interferon-β1b therapy. METHODS The study population included 15 (12 women, 3 men) untreated MS patients and 12 (10 women, 2 men) interferon-β1b treated MS patients with clinically definite relapsing MS (McDonalds criteria) for at least 1 year and a baseline EDSS score of 1.0 to 3.5 inclusive. Patients were treated with 250 μg IU interferon-β1b s.c. every second day during 30 months. The disease course was evaluated using correlations between baseline EDSS score and relapse rates in both groups. RESULTS During interferon-β1b treatment, EDSS scores in treated patients were decreased compared to untreated ones - after 18 and 30 months (p<0.05). In interferon-β1b treated MS patients, NO(2)+NO(3), 3-NT and RSNO plasma concentrations were significantly lower (p<0.05), while arginase activity, ADMA and SDMA levels were significantly increased (p<0.05) during the therapy, compared to the baseline levels in treated patients. CONCLUSION The investigated parameters may be the new biomarkers, providing information for the therapeutic approach and valuable in clinical monitoring.

The Prevalence of Pain in Adults with Multiple Sclerosis: A Multicenter Cross-Sectional Survey

OBJECTIVE Examination of prevalence, intensity and associations of pain in persons with multiple sclerosis (MS). DESIGN Multicenter, international cross-sectional survey. SETTING Patients were recruited from seven MS centers: in Serbia (Clinic of Neurology, Clinical Center of Serbia, Belgrade; Clinic of Neurology, Military Medical Academy, Belgrade; Clinic of Neurology, Clinical Center Kragujevac; Clinic of Neurology, Clinical Center Nis; Department of Neurology, General Hospital-Uzice), in Republic of Srpska-Bosnia and Herzegovina (Clinic of Neurology, Clinical Center Banja Luka) and in Croatia (University Department of Neurology, Sestre Milosrdnice University Hospital Center, Zagreb). SUBJECTS Six hundred and fifty consecutive MS patients diagnosed according to the Revised McDonald criteria (2005), from the aforementioned centers, over the period of 6 months. METHODS A semistructured questionnaire was administered during a face-to-face interview with neurologists who also performed Expanded Disability Status Scale (EDSS), the Hamilton Rating Scale for Depression (HDRS) and Hamilton Rating Scale for Anxiety (HARS). To recognize predictive factors for the presence of pain, the linear regression analysis was used. RESULTS Lifetime prevalence of pain was 66.5% (point prevalence = 44.3%). The prevalence of the comorbidity of pain and depression was 29.1%. Older age (P < 0.001), primary-progressive MS (P = 0.034), higher EDSS score (P = 0.008), higher scores of HDRS (P < 0.001), and HARS (P < 0.001) were significantly associated with pain. Finally, in our multivariate linear regression analysis, anxiety (P < 0.001) was the independent predictor of pain. CONCLUSIONS We confirmed high prevalence of pain, affecting approximately more than half of patients during the course of MS. Pain in MS is associated with disability, depression and, especially with anxiety, which has significant implications for treatment.

Association of serum bilirubin and uric acid levels changes during neuroinflammation in patients with initial and relapsed demyelination attacks

In order to examine the endogenous antioxidants values in the earliest phase of demyelination, we have determined bilirubin and uric acid (UA) serum values in the patients with clinically isolated syndrome (CIS) and relapsing remitting multiple sclerosis (RRMS), regarding their clinical disability, measured by Extended Disability Status Scale (EDSS), Magnetic Resonance Imaging (MRI), disease duration, gender and other parameters. The bilirubin and UA levels were lower in CIS and RRMS patients than in control group, whether male or female (p < 0.05). The bilirubin and UA levels were decreased in RRMS compared to CIS patients (p < 0.05). Regarding EDSS, MRI and disease duration, obtained values of bilirubin and UA were higher in both study groups in patients with lower EDSS, lower MRI lesion number and shorter disease duration (p < 0.05). The greatest significance in decreased bilirubin and UA levels was observed in female compared to male patients, in both study groups (p < 0.05). The results suggest negative linear correlation between bilirubin and UA levels and disease duration, EDSS and MRI in CIS (p < 0.01), with the same correlation between bilirubin and UA levels and disease duration in RRMS patients (p < 0.01). There was also significant correlation between bilirubin level and MRI findings and UA levels and EDSS in RRMS patients (p < 0.01). The obtained results point to the importance of endogenous antioxidants in the outbreak and course of neuroinflammation. This could be favorable for the new pathogenetically conditioned neuroinflammatory therapy concepts which do not initially rely only on immunomodulatory, but also on the antioxidative effects.

The Role of Matrix Metalloproteinase 3 and 9 in the Pathogenesis of Acute Neuroinflammation. Implications for Disease Modifying Therapy.

Matrix metalloproteinases (MMPs) are proteolytic enzymes that are involved in a variety of physiological and pathological processes, including those in CNS. In this study, plasma values of MMP-3 and MMP-9 have been compared in clinically isolated syndrome (CIS) and relapsing-remitting multiple sclerosis (RRMS) patients during their acute attacks, in relation to the biological activity of disease. Therefore, we compared the MMPs plasma values regarding Expanded Disability Status Scale (EDSS), progression index of disease (PID), acute brain lesion volume seen on magnetic resonance imaging (MRI) and index of blood-brain barrier (BBB) permeability destruction. The obtained results demonstrated higher plasma values of MMPs in both study groups than control values (p < 0.05). No statistical significances have been detected comparing the obtained values of both enzymes between CIS and RRMS group (p > 0.05). In both CIS and RRMS groups, the patients with higher EDSS showed higher MMPs plasma values (p < 0.05). The MMPs values were also significantly higher in both study patients with higher total number comparing to those with lower number of MRI brain lesion (p < 0.05) (beyond MMP-3 in RRMS). All obtained correlations, between MMPs and EDSS, PID, volume of MRI Gd-enhancement brain lesions, and index of BBB permeability, were positive (p < 0.05.) This study demonstrates alterations of both tested MMPs with closed correlation with the disease biological activity. Although MMPs are being implicated in the pathogenesis of acute neuroinflammation, the MMPs modulation might be useful in the future design of disease modifying therapy with the specific target profile.

NITRIC OXIDE - MEDIATED SIGNALIZATION AND NITROSATIVE STRESS IN NEUROPATHOLOGY AZOT OKSID - POSREDOVANA SIGNALIZACIJA I NITROZATIVNI STRES U NEUROPATOLOGIJI

Summary Nitric oxide (NO) is an important signalling molecule in a variety of physiological processes. NO, a gas, is produced from L-arginine by different isoforms of the nitric oxide synthase and serves as mediator in important physiological functions, such as promoting vasodilation of blood vessels and mediating communication between nervous system cells. Contradictory to its physiologic actions, free radical activity of NO can cause cellular damage by the induction of nitrosative stress with significant implications on nervous system diseases. Although the mechanism of NOmediated neurodegeneration still remains unclear, numerous studies suggest its crucial role in modification of protein functions by nitrosylation and nitro-tyrosination. NO contributes to glutamate excitotoxicity, participates in organelle fragmentation, inhibits mitochondrial respiratory complexes and mobilizes zinc from the internal stores. Recently, NO has been emerged as a mediator of epigenetic gene expression and chromatin changes. Besides, NO is a key mediator in the regulation of inflammatory and immune response of the central nervous system. It is involved in down regulation of several aspects of CNS inflammation, but also has a dual role in that it is required for inflammation in some situations. Kratak sadržaj Azot monoksid je va`an signalni molekul u brojnim fiziolo{kim procesima. Ovaj gas se stvara iz L-argi - nina dejstvom tri izoforme azot monoksid sintaze i medijator je va`nih fiziolo{kih funkcija, kao {to su posredovanje u re - gulaciji tonusa krvnih sudova i komunikaciji }elija nervnog sistema. Nasuprot ovim ulogama, kao slobodni radikal, NO mo`e izazvati }elijsko o{te}enje indukcijom nitrozativnog stresa, {to ima zna~ajne implikacije u bolestima nervnog sistema. Mada je mehanizam neurodegeneracije posredovane azot monoksidom jo{ uvek nerazja{njen, brojne studije uka - zu ju na njegovu klju~nu ulogu u modifikaciji funkcije protei - na kroz procese S-nitrozilacije i nitrovanja tirozina. On doprinosi glutamatnoj ekscitotoksi~nosti, u~estvuje u fragmentaciji organela, inhibi{e mitohondrijalne respiratorne komplekse i mobili{e cink iz unutra{njih depoa. Nedavno je ukazano da mo`e biti medijator epigenetske genske ekspresije i promena hromatina. Pored toga, NO je klju~ni posrednik u regulaciji inflamatornog i imunog odgovora CNS. On u~estvuje u nishodnoj regulaciji nekoliko aspekata inflamacije CNS, ali tako|e ispoljava dualisti~ke efekte u uslovima inflamacije.