TY  - JOUR
A1  - Neuhaus, Winfried
A1  - Gaiser, Fabian
A1  - Mahringer, Anne
A1  - Franz, Jonas
A1  - Riethmüller, Christoph
A1  - Förster, Carola
T1  - The pivotal role of astrocytes in an in vitro stroke model of the blood-brain barrier
JF  - Frontiers in Cellular Neuroscience
N2  - Stabilization of the blood-brain barrier during and after stroke can lead to less adverse outcome. For elucidation of underlying mechanisms and development of novel therapeutic strategies validated in vitro disease models of the blood-brain barrier could be very helpful. To mimic in vitro stroke conditions we have established a blood-brain barrier in vitro model based on mouse cell line cerebEND and applied oxygen/glucose deprivation (OGD). The role of astrocytes in this disease model was investigated by using cell line C6. Transwell studies pointed out that addition of astrocytes during OGD increased the barrier damage significantly in comparison to the endothelial monoculture shown by changes of transendothelial electrical resistance as well as fluorescein permeability data. Analysis on mRNA and protein levels by qPCR, western blotting and immunofluorescence microscopy of tight junction molecules claudin-3,-5,-12, occludin and ZO-1 revealed that their regulation and localisation is associated with the functional barrier breakdown. Furthermore, soluble factors of astrocytes, OGD and their combination were able to induce changes of functionality and expression of ABC-transporters Abcb1a (P-gp), Abcg2 (bcrp), and Abcc4 (mrp4). Moreover, the expression of proteases (matrixmetalloproteinases MMP-2, MMP-3, MMP-9, and t-PA) as well as of their endogenous inhibitors (TIMP-1, TIMP-3, PAI-1) was altered by astrocyte factors and OGD which resulted in significant changes of total MMP and t-PA activity. Morphological rearrangements induced by OGD and treatment with astrocyte factors were confirmed at a nanometer scale using atomic force microscopy. In conclusion, astrocytes play a major role in blood-brain barrier breakdown during OGD in vitro.
KW  - oxygen/glucose deprivation
KW  - ischemia
KW  - traumatic brain injury
KW  - cerebEND
KW  - C6
KW  - stroke
KW  - in vitro
KW  - blood-brain barrier
Y1  - 2014
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-118297
SN  - 1662-5102
VL  - 8
ER  - 
TY  - THES
A1  - Gaiser, Fabian
T1  - Der Einfluss von NMDA-Rezeptor-Modulatoren auf die Blut-Hirn Schranke unter ischämischen Bedingungen
T1  - The influence of NMDA receptor modulators on the blood-brain barrier under ischemic conditions
N2  - Im Rahmen dieser Arbeit wurde das Motilitätsverhalten von Blut-Hirn Schranken-Endothelzellen unter ischämischen Bedingungen an Hand der cerebEND-Zelllinie untersucht. Da es bisher noch kein Modell für diese Fragestellung gab, wurde zunächst ein solches mit Hilfe des kommerziellen Motilitätsassay der Firma ibidi® etabliert. Danach konnte der Einfluss von ischämischen Bedingungen, von Astrozyten konditioniertem Medium (C6-Zelllinie) und letztendlich der therapeutische Ansatz durch Modulation des NMDA-Rezeptors untersucht werden. Dabei zeigte sich durch das C6-konditionierte Medium eine deutliche Zunahme der Motilität. Diese verstärkte Motilität konnte durch den NMDA-Rezeptor-Antagonisten MK801 verhindert werden. Trotz Analyse einiger an der Proliferation und Migration beteiligter Botenstoffe wie VEGF und MMPs konnte keine Regulation dieser durch MK801 nachgewiesen werden.
N2  - In this work, the motility behavior of blood-brain barrier endothelial cells under ischemic conditions was investigated using the cerebEND cell line. As there was no model for this question available until now, a model was first established using the commercial motility assay of the company ibidi®. Subsequently, the influence of ischemic conditions, astrocyte conditioned medium (C6-cell line) and finally the therapeutic approach by modulation of the NMDA receptor could be investigated. The C6-conditioned medium showed a significant increase in motility. This increased motility could be prevented by the NMDA receptor antagonist MK801. Despite analysis of some messenger substances involved in the proliferation and migration such as VEGF and MMPs, no regulation of these substances by MK801 could be detected.
KW  - NMDA-Rezeptor
KW  - Blut-Hirn-Schranke
KW  - Ischämie
KW  - NMDA-Antagonist
KW  - Hirnschädigung
KW  - MK801
Y1  - 2020
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-202365
ER  -