@article{SalvadorBurekFoerster2015, author = {Salvador, Ellaine and Burek, Malgorzata and F{\"o}rster, Carola Y.}, title = {Stretch and/or oxygen glucose deprivation (OGD) in an in vitro traumatic brain injury (TBI) model induces calcium alteration and inflammatory cascade}, series = {Frontiers in Cellular Neuroscience}, volume = {9}, journal = {Frontiers in Cellular Neuroscience}, number = {323}, doi = {10.3389/fncel.2015.00323}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-148255}, year = {2015}, abstract = {The blood-brain barrier (BBB), made up of endothelial cells of capillaries in the brain, maintains the microenvironment of the central nervous system. During ischemia and traumatic brain injury (TBI), cellular disruption leading to mechanical insult results to the BBB being compromised. Oxygen glucose deprivation (OGD) is the most commonly used in vitro model for ischemia. On the other hand, stretch injury is currently being used to model TBI in vitro. In this paper, the two methods are used alone or in combination, to assess their effects on cerebrovascular endothelial cells cEND in the presence or absence of astrocytic factors. Applying severe stretch and/or OGD to cEND cells in our experiments resulted to cell swelling and distortion. Damage to the cells induced release of lactate dehydrogenase enzyme (LDH) and nitric oxide (NO) into the cell culture medium. In addition, mRNA expression of inflammatory markers interleukin (I L)-6, IL-1\(\alpha\) chemokine (C-C motif) ligand 2 (CCL2) and tumor necrosis factor (TNF)-\(\alpha\) also increased. These events could lead to the opening of calcium ion channels resulting to excitotoxicity. This could be demonstrated by increased calcium level in OGD-subjected cEND cells incubated with astrocyte-conditioned medium. Furthermore, reduction of cell membrane integrity decreased tight junction proteins claudin-5 and occludin expression. In addition, permeability of the endothelial cell monolayer increased. Also, since cell damage requires an increased uptake of glucose, expression of glucose transporter glut1 was found to increase at the mRNA level after OGD. Overall, the effects of OGD on cEND cells appear to be more prominent than that of stretch with regards to TJ proteins, NO, glutl expression, and calcium level. Astrocytes potentiate these effects on calcium level in cEND cells. Combining both methods to model TBI in vitro shows a promising improvement to currently available models.}, language = {en} } @article{BurekBurmesterSalvadoretal.2020, author = {Burek, Malgorzata and Burmester, Sandra and Salvador, Ellaine and M{\"o}ller-Ehrlich, Kerstin and Schneider, Reinhard and Roewer, Norbert and Nagai, Michiaki and F{\"o}rster, Carola Y.}, title = {Kidney Ischemia/Reperfusion Injury Induces Changes in the Drug Transporter Expression at the Blood-Brain Barrier in vivo and in vitro}, series = {Frontiers in Physiology}, volume = {11}, journal = {Frontiers in Physiology}, issn = {1664-042X}, doi = {10.3389/fphys.2020.569881}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-216413}, year = {2020}, abstract = {Ischemia/reperfusion injury is a major cause of acute kidney injury (AKI). AKI is characterized by a sudden decrease in kidney function, systemic inflammation, oxidative stress, and dysregulation of the sodium, potassium, and water channels. While AKI leads to uremic encephalopathy, epidemiological studies have shown that AKI is associated with a subsequent risk for developing stroke and dementia. To get more insights into kidney-brain crosstalk, we have created an in vitro co-culture model based on human kidney cells of the proximal tubule (HK-2) and brain microvascular endothelial cells (BMEC). The HK-2 cell line was grown to confluence on 6-well plates and exposed to oxygen/glucose deprivation (OGD) for 4 h. Control HK-2 cells were grown under normal conditions. The BMEC cell line cerebED was grown to confluence on transwells with 0.4 μm pores. The transwell filters seeded and grown to confluence with cereEND were inserted into the plates with HK-2 cells with or without OGD treatment. In addition, cerebEND were left untreated or treated with uremic toxins, indole-3-acetic acid (IAA) and indoxyl sulfate (IS). The protein and mRNA expression of selected BBB-typical influx transporters, efflux transporters, cellular receptors, and tight junction proteins was measured in BMECs. To validate this in vitro model of kidney-brain interaction, we isolated brain capillaries from mice exposed to bilateral renal ischemia (30 min)/reperfusion injury (24 h) and measured mRNA and protein expression as described above. Both in vitro and in vivo systems showed similar changes in the expression of drug transporters, cellular receptors, and tight junction proteins. Efflux pumps, in particular Abcb1b, Abcc1, and Abcg2, have shown increased expression in our model. Thus, our in vitro co-culture system can be used to study the cellular mechanism of kidney and brain crosstalk in renal ischemia/reperfusion injury.}, language = {en} }