TY - JOUR A1 - Reschke, Moritz A1 - Salvador, Ellaine A1 - Schlegel, Nicolas A1 - Burek, Malgorzata A1 - Karnati, Srikanth A1 - Wunder, Christian A1 - Förster, Carola Y. T1 - Isosteviol sodium (STVNA) reduces pro-inflammatory cytokine IL-6 and GM-CSF in an in vitro murine stroke model of the blood–brain barrier (BBB) JF - Pharmaceutics N2 - Early treatment with glucocorticoids could help reduce both cytotoxic and vasogenic edema, leading to improved clinical outcome after stroke. In our previous study, isosteviol sodium (STVNA) demonstrated neuroprotective effects in an in vitro stroke model, which utilizes oxygen-glucose deprivation (OGD). Herein, we tested the hypothesis that STVNA can activate glucocorticoid receptor (GR) transcriptional activity in brain microvascular endothelial cells (BMECs) as previously published for T cells. STVNA exhibited no effects on transcriptional activation of the glucocorticoid receptor, contrary to previous reports in Jurkat cells. However, similar to dexamethasone, STVNA inhibited inflammatory marker IL-6 as well as granulocyte-macrophage colony-stimulating factor (GM-CSF) secretion. Based on these results, STVNA proves to be beneficial as a possible prevention and treatment modality for brain ischemia-reperfusion injury-induced blood–brain barrier (BBB) dysfunction. KW - IL-6 KW - ischemia KW - isosteviol sodium (STVNA) KW - dexamethasone KW - glucocorticoid receptor KW - cerebEND Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-286275 SN - 1999-4923 VL - 14 IS - 9 ER - TY - JOUR A1 - Salvador, Ellaine A1 - Kessler, Almuth F. A1 - Domröse, Dominik A1 - Hörmann, Julia A1 - Schaeffer, Clara A1 - Giniunaite, Aiste A1 - Burek, Malgorzata A1 - Tempel-Brami, Catherine A1 - Voloshin, Tali A1 - Volodin, Alexandra A1 - Zeidan, Adel A1 - Giladi, Moshe A1 - Ernestus, Ralf-Ingo A1 - Löhr, Mario A1 - Förster, Carola Y. A1 - Hagemann, Carsten T1 - Tumor Treating Fields (TTFields) reversibly permeabilize the blood–brain barrier in vitro and in vivo JF - Biomolecules N2 - Despite the availability of numerous therapeutic substances that could potentially target CNS disorders, an inability of these agents to cross the restrictive blood–brain barrier (BBB) limits their clinical utility. Novel strategies to overcome the BBB are therefore needed to improve drug delivery. We report, for the first time, how Tumor Treating Fields (TTFields), approved for glioblastoma (GBM), affect the BBB’s integrity and permeability. Here, we treated murine microvascular cerebellar endothelial cells (cerebEND) with 100–300 kHz TTFields for up to 72 h and analyzed the expression of barrier proteins by immunofluorescence staining and Western blot. In vivo, compounds normally unable to cross the BBB were traced in healthy rat brain following TTFields administration at 100 kHz. The effects were analyzed via MRI and immunohistochemical staining of tight-junction proteins. Furthermore, GBM tumor-bearing rats were treated with paclitaxel (PTX), a chemotherapeutic normally restricted by the BBB combined with TTFields at 100 kHz. The tumor volume was reduced with TTFields plus PTX, relative to either treatment alone. In vitro, we demonstrate that TTFields transiently disrupted BBB function at 100 kHz through a Rho kinase-mediated tight junction claudin-5 phosphorylation pathway. Altogether, if translated into clinical use, TTFields could represent a novel CNS drug delivery strategy. KW - blood–brain barrier KW - TTFields KW - CNS disorders Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-288057 SN - 2218-273X VL - 12 IS - 10 ER - TY - JOUR A1 - Reinhold, Ann Kristin A1 - Krug, Susanne M. A1 - Salvador, Ellaine A1 - Sauer, Reine S. A1 - Karl-Schöller, Franziska A1 - Malcangio, Marzia A1 - Sommer, Claudia A1 - Rittner, Heike L. T1 - MicroRNA-21-5p functions via RECK/MMP9 as a proalgesic regulator of the blood nerve barrier in nerve injury JF - Annals of the New York Academy of Sciences N2 - Both nerve injury and complex regional pain syndrome (CRPS) can result in chronic pain. In traumatic neuropathy, the blood nerve barrier (BNB) shielding the nerve is impaired—partly due to dysregulated microRNAs (miRNAs). Upregulation of microRNA-21-5p (miR-21) has previously been documented in neuropathic pain, predominantly due to its proinflammatory features. However, little is known about other functions. Here, we characterized miR-21 in neuropathic pain and its impact on the BNB in a human-murine back translational approach. MiR-21 expression was elevated in plasma of patients with CRPS as well as in nerves of mice after transient and persistent nerve injury. Mice presented with BNB leakage, as well as loss of claudin-1 in both injured and spared nerves. Moreover, the putative miR-21 target RECK was decreased and downstream Mmp9 upregulated, as was Tgfb. In vitro experiments in human epithelial cells confirmed a downregulation of CLDN1 by miR-21 mimics via inhibition of the RECK/MMP9 pathway but not TGFB. Perineurial miR-21 mimic application in mice elicited mechanical hypersensitivity, while local inhibition of miR-21 after nerve injury reversed it. In summary, the data support a novel role for miR-21, independent of prior inflammation, in elicitation of pain and impairment of the BNB via RECK/MMP9. KW - claudin-1 KW - RECK KW - MMP9 KW - CRPS KW - microRNA KW - neuropathic pain KW - blood nerve barrier Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-318226 VL - 1515 IS - 1 SP - 184 EP - 195 ER - TY - JOUR A1 - Nickl, Vera A1 - Schulz, Ellina A1 - Salvador, Ellaine A1 - Trautmann, Laureen A1 - Diener, Leopold A1 - Kessler, Almuth F. A1 - Monoranu, Camelia M. A1 - Dehghani, Faramarz A1 - Ernestus, Ralf-Ingo A1 - Löhr, Mario A1 - Hagemann, Carsten T1 - Glioblastoma-derived three-dimensional ex vivo models to evaluate effects and efficacy of Tumor Treating Fields (TTFields) JF - Cancers N2 - Simple Summary In glioblastoma, tumor recurrence is inevitable and the prognosis of patients is poor, despite multidisciplinary treatment approaches involving surgical resection, radiotherapy and chemotherapy. Recently, Tumor Treating Fields (TTFields) have been added to the therapeutic set-up. These alternating electric fields are applied to glioblastoma at 200 kHz frequency via arrays placed on the shaved scalp of patients. Patients show varying response to this therapy. Molecular effects of TTFields have been investigated largely in cell cultures and animal models, but not in patient tissue samples. Acquisition of matched treatment-naïve and recurrent patient tissues is a challenge. Therefore, we suggest three reliable patient-derived three-dimensional ex vivo models (primary cells grown as microtumors on murine organotypic hippocampal slices, organoids and tumor slice cultures) which may facilitate prediction of patients’ treatment responses and provide important insights into clinically relevant cellular and molecular alterations under TTFields. Abstract Glioblastoma (GBM) displays a wide range of inter- and intra-tumoral heterogeneity contributing to therapeutic resistance and relapse. Although Tumor Treating Fields (TTFields) are effective for the treatment of GBM, there is a lack of ex vivo models to evaluate effects on patients’ tumor biology or to screen patients for treatment efficacy. Thus, we adapted patient-derived three-dimensional tissue culture models to be compatible with TTFields application to tissue culture. Patient-derived primary cells (PDPC) were seeded onto murine organotypic hippocampal slice cultures (OHSC), and microtumor development with and without TTFields at 200 kHz was observed. In addition, organoids were generated from acute material cultured on OHSC and treated with TTFields. Lastly, the effect of TTFields on expression of the Ki67 proliferation marker was evaluated on cultured GBM slices. Microtumors exhibited increased sensitivity towards TTFields compared to monolayer cell cultures. TTFields affected tumor growth and viability, as the size of microtumors and the percentage of Ki67-positive cells decreased after treatment. Nevertheless, variability in the extent of the response was preserved between different patient samples. Therefore, these pre-clinical GBM models could provide snapshots of the tumor to simulate patient treatment response and to investigate molecular mechanisms of response and resistance. KW - glioblastoma KW - Tumor Treating Fields (TTFields) KW - organotypic hippocampal slice cultures (OHSC) KW - organoids KW - tumor slice cultures KW - 3D ex vivo models Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-290340 SN - 2072-6694 VL - 14 IS - 21 ER -