Browsing by Author "Tasic, Jelena (57816681400)"

We examined the role of endoplasmic reticulum (ER) stress and the ensuing unfolded protein response (UPR) in the development of the central nervous system (CNS)-directed immune response in the rat model of experimental autoimmune encephalomyelitis (EAE). The induction of EAE with syngeneic spinal cord homogenate in complete Freund's adjuvant (CFA) caused a time-dependent increase in the expression of ER stress/UPR markers glucose-regulated protein 78 (GRP78), X-box-binding protein 1 (XBP1), C/EBP homologous protein (CHOP), and phosphorylated eukaryotic initiation factor 2α (eIF2α) in the draining lymph nodes of both EAE-susceptible Dark Agouti (DA) and EAE-resistant Albino Oxford (AO) rats. However, the increase in ER stress markers was more pronounced in AO rats. CFA alone also induced ER stress, but the effect was weaker and less sustained compared to full immunization. The ultrastructural analysis of DA lymph node tissue by electron microscopy revealed ER dilatation in lymphocytes, macrophages, and plasma cells, while immunoblot analysis of CD3-sorted lymph node cells demonstrated the increase in ER stress/UPR markers in both CD3+ (T cell) and CD3− (non-T) cell compartments. A positive correlation was observed between the levels of ER stress/UPR markers in the CNS-infiltrated mononuclear cells and the clinical activity of the disease. Finally, the reduction of EAE clinical signs by ER stress inhibitor ursodeoxycholic acid was associated with the decrease in the expression of mRNA encoding pro-inflammatory cytokines TNF and IL-1β, and encephalitogenic T cell cytokines IFN-γ and IL-17. Collectively, our data indicate that ER stress response in immune cells might be an important pathogenetic factor and a valid therapeutic target in the inflammatory damage of the CNS. © 2024 European Federation of Immunological Societies

We examined the role of endoplasmic reticulum (ER) stress and the ensuing unfolded protein response (UPR) in the development of the central nervous system (CNS)-directed immune response in the rat model of experimental autoimmune encephalomyelitis (EAE). The induction of EAE with syngeneic spinal cord homogenate in complete Freund's adjuvant (CFA) caused a time-dependent increase in the expression of ER stress/UPR markers glucose-regulated protein 78 (GRP78), X-box-binding protein 1 (XBP1), C/EBP homologous protein (CHOP), and phosphorylated eukaryotic initiation factor 2α (eIF2α) in the draining lymph nodes of both EAE-susceptible Dark Agouti (DA) and EAE-resistant Albino Oxford (AO) rats. However, the increase in ER stress markers was more pronounced in AO rats. CFA alone also induced ER stress, but the effect was weaker and less sustained compared to full immunization. The ultrastructural analysis of DA lymph node tissue by electron microscopy revealed ER dilatation in lymphocytes, macrophages, and plasma cells, while immunoblot analysis of CD3-sorted lymph node cells demonstrated the increase in ER stress/UPR markers in both CD3+ (T cell) and CD3− (non-T) cell compartments. A positive correlation was observed between the levels of ER stress/UPR markers in the CNS-infiltrated mononuclear cells and the clinical activity of the disease. Finally, the reduction of EAE clinical signs by ER stress inhibitor ursodeoxycholic acid was associated with the decrease in the expression of mRNA encoding pro-inflammatory cytokines TNF and IL-1β, and encephalitogenic T cell cytokines IFN-γ and IL-17. Collectively, our data indicate that ER stress response in immune cells might be an important pathogenetic factor and a valid therapeutic target in the inflammatory damage of the CNS. © 2024 European Federation of Immunological Societies

Glioblastomas are aggressive and usually incurable high-grade gliomas without adequate treatment. In this study, we aimed to investigate the potential of desloratadine to induce apoptosis/autophagy as genetically regulated processes that can seal cancer cell fates. All experiments were performed on U251 human glioblastoma cell line and primary human glioblastoma cell culture. Cytotoxic effect of desloratadine was investigated using MTT and CV assays, while oxidative stress, apoptosis, and autophagy were detected by flow cytometry and immunoblot. Desloratadine treatment decreased cell viability of U251 human glioblastoma cell line and primary human glioblastoma cell culture (IC50 value 50 µM) by an increase of intracellular reactive oxygen species and caspase activity. Also, desloratadine decreased the expression of main autophagy repressor mTOR and its upstream activator Akt and increased the expression of AMPK. Desloratadine exerted dual cytotoxic effect inducing both apoptosis- and mTOR/AMPK-dependent cytotoxic autophagy in glioblastoma cells and primary glioblastoma cell culture. © 2023, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.

Glioblastomas are aggressive and usually incurable high-grade gliomas without adequate treatment. In this study, we aimed to investigate the potential of desloratadine to induce apoptosis/autophagy as genetically regulated processes that can seal cancer cell fates. All experiments were performed on U251 human glioblastoma cell line and primary human glioblastoma cell culture. Cytotoxic effect of desloratadine was investigated using MTT and CV assays, while oxidative stress, apoptosis, and autophagy were detected by flow cytometry and immunoblot. Desloratadine treatment decreased cell viability of U251 human glioblastoma cell line and primary human glioblastoma cell culture (IC50 value 50 µM) by an increase of intracellular reactive oxygen species and caspase activity. Also, desloratadine decreased the expression of main autophagy repressor mTOR and its upstream activator Akt and increased the expression of AMPK. Desloratadine exerted dual cytotoxic effect inducing both apoptosis- and mTOR/AMPK-dependent cytotoxic autophagy in glioblastoma cells and primary glioblastoma cell culture. © 2023, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.

Mott cells are plasma cells that have multiple spherical Russell bodies packed in their cytoplasm. Russell bodies are dilated endoplasmic reticulum cisternae filled with aggregates of immunoglobulins that are neither secreted nor degraded. Mott cells were observed in our study by light and electron microscope in the lymph nodes of rats with experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis. Mott cells were detected on hematoxylin and eosin (HE)-stained lymph node sections as vacuolated cells with eccentrically positioned nuclei and large number of faint blue spherical inclusions in the cytoplasm. Electron microscopic investigation revealed the presence of Russell bodies of the “medusa” form inside Mott cells in lymph node ultra-thin sections of EAE animals. Mott cells expressed the plasma cell marker CD138 and either kappa or lambda immunoglobulin light chains, indicating their origin from polyclonally activated B cells. Finally, Mott cells were associated with active EAE, as they were not found in the lymph nodes of EAE-resistant Albino Oxford rats. The presence of Russell bodies implies an excessive production of immunoglobulins in EAE, thus further emphasizing the role of B cells, and among them Mott cells, in the pathogenesis of this animal model of multiple sclerosis. © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2023.

Mott cells are plasma cells that have multiple spherical Russell bodies packed in their cytoplasm. Russell bodies are dilated endoplasmic reticulum cisternae filled with aggregates of immunoglobulins that are neither secreted nor degraded. Mott cells were observed in our study by light and electron microscope in the lymph nodes of rats with experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis. Mott cells were detected on hematoxylin and eosin (HE)-stained lymph node sections as vacuolated cells with eccentrically positioned nuclei and large number of faint blue spherical inclusions in the cytoplasm. Electron microscopic investigation revealed the presence of Russell bodies of the “medusa” form inside Mott cells in lymph node ultra-thin sections of EAE animals. Mott cells expressed the plasma cell marker CD138 and either kappa or lambda immunoglobulin light chains, indicating their origin from polyclonally activated B cells. Finally, Mott cells were associated with active EAE, as they were not found in the lymph nodes of EAE-resistant Albino Oxford rats. The presence of Russell bodies implies an excessive production of immunoglobulins in EAE, thus further emphasizing the role of B cells, and among them Mott cells, in the pathogenesis of this animal model of multiple sclerosis. © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2023.