Browsing by Author "Stojković, Marija Mostarica (6701741422)"

Dimethyl fumarate (DMF), a new drug for multiple sclerosis (MS) treatment, acts against neuroinflammation via mechanisms that are triggered by adduct formation with thiol redox switches. Ethyl pyruvate (EP), an off-the-shelf agent, appears to be a redox analog of DMF, but its immunomodulatory properties have not been put into the context of MS therapy. In this article, we examined and compared the effects of EP and DMF on MS-relevant activity/functions of T cells, macrophages, microglia, and astrocytes. EP efficiently suppressed the release of MS signature cytokines, IFN-γ and IL-17, from human PBMCs. Furthermore, the production of these cytokines was notably decreased in encephalitogenic T cells after in vivo application of EP to rats. Production of two other proinflammatory cytokines, IL-6 and TNF, and NO was suppressed by EP in macrophages and microglia. Reactive oxygen species production in macrophages, microglia activation, and the development of Ag-presenting phenotype in microglia and macrophages were constrained by EP. The release of IL-6 was reduced in astrocytes. Finally, EP inhibited the activation of transcription factor NF-κB in microglia and astrocytes. Most of these effects were also found for DMF, implying that EP and DMF share common targets and mechanisms of action. Importantly, EP had in vivo impact on experimental autoimmune encephalomyelitis, an animal model of MS. Treatment with EP resulted in delay and shortening of the first relapse, and lower clinical scores, whereas the second attack was annihilated. Further studies on the possibility to use EP as an MS therapeutic are warranted. Copyright © 2015 by The American Association of Immunologists, Inc.

Dimethyl fumarate (DMF), a new drug for multiple sclerosis (MS) treatment, acts against neuroinflammation via mechanisms that are triggered by adduct formation with thiol redox switches. Ethyl pyruvate (EP), an off-the-shelf agent, appears to be a redox analog of DMF, but its immunomodulatory properties have not been put into the context of MS therapy. In this article, we examined and compared the effects of EP and DMF on MS-relevant activity/functions of T cells, macrophages, microglia, and astrocytes. EP efficiently suppressed the release of MS signature cytokines, IFN-γ and IL-17, from human PBMCs. Furthermore, the production of these cytokines was notably decreased in encephalitogenic T cells after in vivo application of EP to rats. Production of two other proinflammatory cytokines, IL-6 and TNF, and NO was suppressed by EP in macrophages and microglia. Reactive oxygen species production in macrophages, microglia activation, and the development of Ag-presenting phenotype in microglia and macrophages were constrained by EP. The release of IL-6 was reduced in astrocytes. Finally, EP inhibited the activation of transcription factor NF-κB in microglia and astrocytes. Most of these effects were also found for DMF, implying that EP and DMF share common targets and mechanisms of action. Importantly, EP had in vivo impact on experimental autoimmune encephalomyelitis, an animal model of MS. Treatment with EP resulted in delay and shortening of the first relapse, and lower clinical scores, whereas the second attack was annihilated. Further studies on the possibility to use EP as an MS therapeutic are warranted. Copyright © 2015 by The American Association of Immunologists, Inc.

We have shown recently that xanthine derivative pentoxifylline (PTX) downregulates an inflammatory autoimmune process triggered in genetically susceptible Dark Agouti rats by multiple low doses of streptozotocin (MLD-SZ, 20 mg/kg/day ip for 5 days). We studied the cellular and molecular consequences of PTX treatment during MLD-SZ-induced diabetes with special emphasis on local vs. systemic production of inflammatory mediators. Administration of PTX (200 mg/kg/day for 10 days) during induction of the disease reduced clinical signs of diabetes and protected rats from development of destructive intrainsulitis. Pentoxifylline did not affect diabetogenic effect of single high dose of SZ (100 mg/kg SZ). Ex vivo analysis of the islets of Langerhans performed in early disease development revealed that PTX downregulates production of proinflammatory cytokines IFN-γ and TNF, as well as inducible nitric oxide synthase (iNOS) expression and NO production. In addition, PTX treatment suppressed splenocyte autoreactivity, as well as the frequency of cells expressing IL-2R and MHC class II antigens. There was no evidence of any changes in proportion of ICAM-1 and LFA-1 expressing splenocytes in comparison to control MLD-SZ-treated animals. In contrast to suppressed intraislet production, high peripheral expression of both inos mRNA and NO was found in MLD-SZ rats treated with PTX. Taken together, the data indicate that the effect on both systemic and intra-islet production of NO, suppression of autoreactive cell activation and of local type 1 cytokine release may contribute to the therapeutic benefit achieved by PTX in the rat. © 2001 Academic Press.

We have shown recently that xanthine derivative pentoxifylline (PTX) downregulates an inflammatory autoimmune process triggered in genetically susceptible Dark Agouti rats by multiple low doses of streptozotocin (MLD-SZ, 20 mg/kg/day ip for 5 days). We studied the cellular and molecular consequences of PTX treatment during MLD-SZ-induced diabetes with special emphasis on local vs. systemic production of inflammatory mediators. Administration of PTX (200 mg/kg/day for 10 days) during induction of the disease reduced clinical signs of diabetes and protected rats from development of destructive intrainsulitis. Pentoxifylline did not affect diabetogenic effect of single high dose of SZ (100 mg/kg SZ). Ex vivo analysis of the islets of Langerhans performed in early disease development revealed that PTX downregulates production of proinflammatory cytokines IFN-γ and TNF, as well as inducible nitric oxide synthase (iNOS) expression and NO production. In addition, PTX treatment suppressed splenocyte autoreactivity, as well as the frequency of cells expressing IL-2R and MHC class II antigens. There was no evidence of any changes in proportion of ICAM-1 and LFA-1 expressing splenocytes in comparison to control MLD-SZ-treated animals. In contrast to suppressed intraislet production, high peripheral expression of both inos mRNA and NO was found in MLD-SZ rats treated with PTX. Taken together, the data indicate that the effect on both systemic and intra-islet production of NO, suppression of autoreactive cell activation and of local type 1 cytokine release may contribute to the therapeutic benefit achieved by PTX in the rat. © 2001 Academic Press.

Tumor necrosis factor (TNF) α has been considered the prototypic cytopathogenic cytokine in multiple sclerosis (MS), but recently this cytokine has been shown to possess significant anti-inflammatory and neuroprotective effects in demyelinating diseases. It has been reported that the TNFα-308 polymorphism influences levels of TNFα production, and that the rare allele, TNF2, is associated with high TNFα production. We investigated the TNFα-308 polymorphism in 143 unrelated Serbian patients with MS and 123 ethnically matched, healthy individuals using the allele-specific restriction fragment length polymorphism polymerase chain reaction technique. The frequency of the TNF2 allele was significantly decreased in MS patients (14%) in comparison with controls (24%; p = 0.044). The TNF2 allele had no influence on disease behavior, since it was not associated with the course and severity of MS in this group of patients. The result suggests that in the Serbian population polymorphism at position -308 of TNFα or at an adjacent locus might have a role in MS susceptibility. Copyright © 2003 S. Karger AG, Basel.

Tumor necrosis factor (TNF) α has been considered the prototypic cytopathogenic cytokine in multiple sclerosis (MS), but recently this cytokine has been shown to possess significant anti-inflammatory and neuroprotective effects in demyelinating diseases. It has been reported that the TNFα-308 polymorphism influences levels of TNFα production, and that the rare allele, TNF2, is associated with high TNFα production. We investigated the TNFα-308 polymorphism in 143 unrelated Serbian patients with MS and 123 ethnically matched, healthy individuals using the allele-specific restriction fragment length polymorphism polymerase chain reaction technique. The frequency of the TNF2 allele was significantly decreased in MS patients (14%) in comparison with controls (24%; p = 0.044). The TNF2 allele had no influence on disease behavior, since it was not associated with the course and severity of MS in this group of patients. The result suggests that in the Serbian population polymorphism at position -308 of TNFα or at an adjacent locus might have a role in MS susceptibility. Copyright © 2003 S. Karger AG, Basel.

Background: There is an apparently increased tendency toward infections in patients with Gaucher disease, possibly due to defective neutrophil function rather than a decreased neutrophil count. Since macrophages are the main cell type affected in Gaucher disease, our aim was to determine the contribution of these cells to the susceptibility of Gaucher patients to infection by studying the respiratory burst capacity of peripheral blood monocytes. Methods: The study was performed in eleven Gaucher type 1 patients and eleven sex and age matched control subjects by measuring peripheral blood monocytes' respiratory burst capacity using flow cytometry. The respiratory burst capacity was measured as dihydrorhodamine-123 median fluorescence in patients and respective controls. Results: There was no statistical difference in the median fluorescence among the patients and respective controls (p>0.05) after phorbol 12-myristate 13-acetate stimulation. Also, statistical difference was not reached among patients treated with enzyme replacement therapy at the time and those untreated. Conclusions: Flow cytometry might represent a more accurate and more reliable measure of respiratory burst compared to the methods of other researchers. Respiratory burst disturbance in monocytes does not seem to contribute to increased susceptibility to infection in Gaucher patients.

Background: There is an apparently increased tendency toward infections in patients with Gaucher disease, possibly due to defective neutrophil function rather than a decreased neutrophil count. Since macrophages are the main cell type affected in Gaucher disease, our aim was to determine the contribution of these cells to the susceptibility of Gaucher patients to infection by studying the respiratory burst capacity of peripheral blood monocytes. Methods: The study was performed in eleven Gaucher type 1 patients and eleven sex and age matched control subjects by measuring peripheral blood monocytes' respiratory burst capacity using flow cytometry. The respiratory burst capacity was measured as dihydrorhodamine-123 median fluorescence in patients and respective controls. Results: There was no statistical difference in the median fluorescence among the patients and respective controls (p>0.05) after phorbol 12-myristate 13-acetate stimulation. Also, statistical difference was not reached among patients treated with enzyme replacement therapy at the time and those untreated. Conclusions: Flow cytometry might represent a more accurate and more reliable measure of respiratory burst compared to the methods of other researchers. Respiratory burst disturbance in monocytes does not seem to contribute to increased susceptibility to infection in Gaucher patients.

The anticancer activity of platinum complexes has been known since the discovery of classical Pt(II)-based drug cisplatin. However, Pt(IV) complexes have greater inertness than corresponding Pt(II) complexes, thus allowing the oral administration and reducing the toxicity associated with platinum-based chemotherapy. Here, we describe the in vitro antitumor activity of some novel Pt(IV)-based agents against mouse fibrosarcoma L929 cells and human astrocytoma U251 cells. The cytotoxicity of 2 Pt(IV) complexes with bidentate ethylenediamine-N,N′-di-3-propanoato esters was found to be markedly higher than that of their Pt(II) counterparts and comparable to the antitumor action of cisplatin. In contrast to cisplatin, which caused oxidative stress-independent apoptotic cell death of tumor cells, these Pt(IV) complexes induced oxygen radical-mediated tumor cell necrosis. Importantly, the cytotoxic action of novel Pt(IV) complexes was markedly more rapid than that of cisplatin, indicating their potential usefulness in anticancer therapy. © 2005 Wiley-Liss, Inc.

The anticancer activity of platinum complexes has been known since the discovery of classical Pt(II)-based drug cisplatin. However, Pt(IV) complexes have greater inertness than corresponding Pt(II) complexes, thus allowing the oral administration and reducing the toxicity associated with platinum-based chemotherapy. Here, we describe the in vitro antitumor activity of some novel Pt(IV)-based agents against mouse fibrosarcoma L929 cells and human astrocytoma U251 cells. The cytotoxicity of 2 Pt(IV) complexes with bidentate ethylenediamine-N,N′-di-3-propanoato esters was found to be markedly higher than that of their Pt(II) counterparts and comparable to the antitumor action of cisplatin. In contrast to cisplatin, which caused oxidative stress-independent apoptotic cell death of tumor cells, these Pt(IV) complexes induced oxygen radical-mediated tumor cell necrosis. Importantly, the cytotoxic action of novel Pt(IV) complexes was markedly more rapid than that of cisplatin, indicating their potential usefulness in anticancer therapy. © 2005 Wiley-Liss, Inc.

It has been increasingly appreciated that tumor necrosis factor (TNF) performs various protective and anti-inflammatory functions in multiple sclerosis (MS) and its animal model experimental autoimmune encephalomyelitis (EAE). Recently, CXCL12 has been identified as a key inhibitor of leukocyte entry into the central nervous system (CNS) and as a regulator of inflammation resulting from the invasion. Here, a positive correlation between expression of TNF and CXCL12 in the CNS samples of EAE rats is presented. Also, it is shown that TNF potentiates CXCL12 expression in astrocytes. These results contribute to a view that TNF produced within the CNS plays a protective role in neuroinflammation. © 2015 Elsevier GmbH.

It has been increasingly appreciated that tumor necrosis factor (TNF) performs various protective and anti-inflammatory functions in multiple sclerosis (MS) and its animal model experimental autoimmune encephalomyelitis (EAE). Recently, CXCL12 has been identified as a key inhibitor of leukocyte entry into the central nervous system (CNS) and as a regulator of inflammation resulting from the invasion. Here, a positive correlation between expression of TNF and CXCL12 in the CNS samples of EAE rats is presented. Also, it is shown that TNF potentiates CXCL12 expression in astrocytes. These results contribute to a view that TNF produced within the CNS plays a protective role in neuroinflammation. © 2015 Elsevier GmbH.

The levels of uric acid (UA), a natural peroxynitrite scavenger, were measured in sera from 240 patients with multiple sclerosis (MS) and 104 sex- and age-matched control patients with other neurological diseases (OND). The mean serum UA concentration was lower in the MS than in the OND group, but the difference did not reach the level of statistical significance (P=0.068). However, the mean serum UA level from patients with active MS (202.6+67.1 μmol/l) was significantly lower than that in inactive MS patients (226.5+78.6 μmol/l; P=0.046) and OND controls (P=0.007). We found a significant inverse correlation of serum UA concentration with female gender (P=0.0001), disease activity (P=0.012) and duration (P=0.017), and a trend towards an inverse correlation with disability as assessed by EDSS score, which did not reach statistical significance (P=0.067). Finally, multivariate linear regression analyses showed that UA concentration was independently correlated with gender (P=0.0001), disease activity (P=0.014) and duration of the disease (P=0.043) in MS patients. These findings suggest that serum UA might serve as a possible marker of disease activity in MS. They also provide support to the potential beneficial therapeutic effect of radical-scavenging substances in MS.

The levels of uric acid (UA), a natural peroxynitrite scavenger, were measured in sera from 240 patients with multiple sclerosis (MS) and 104 sex- and age-matched control patients with other neurological diseases (OND). The mean serum UA concentration was lower in the MS than in the OND group, but the difference did not reach the level of statistical significance (P=0.068). However, the mean serum UA level from patients with active MS (202.6+67.1 μmol/l) was significantly lower than that in inactive MS patients (226.5+78.6 μmol/l; P=0.046) and OND controls (P=0.007). We found a significant inverse correlation of serum UA concentration with female gender (P=0.0001), disease activity (P=0.012) and duration (P=0.017), and a trend towards an inverse correlation with disability as assessed by EDSS score, which did not reach statistical significance (P=0.067). Finally, multivariate linear regression analyses showed that UA concentration was independently correlated with gender (P=0.0001), disease activity (P=0.014) and duration of the disease (P=0.043) in MS patients. These findings suggest that serum UA might serve as a possible marker of disease activity in MS. They also provide support to the potential beneficial therapeutic effect of radical-scavenging substances in MS.