TY  - JOUR
A1  - Schuhmann, Michael K.
A1  - Fluri, Felix
T1  - Effects of fullerenols on mouse brain microvascular endothelial cells
JF  - International Journal of Molecular Sciences
N2  - Fullerenols, water-soluble C60-fullerene derivatives, have been shown to exert neuroprotective effects in vitro and in vivo, most likely due to their capability to scavenge free radicals. However, little is known about the effects of fullerenols on the blood–brain barrier (BBB), especially on cerebral endothelial cells under inflammatory conditions. Here, we investigated whether the treatment of primary mouse brain microvascular endothelial cells with fullerenols impacts basal and inflammatory blood–brain barrier (BBB) properties in vitro. While fullerenols (1, 10, and 100 µg/mL) did not change transendothelial electrical resistance under basal and inflammatory conditions, 100 µg/mL of fullerenol significantly reduced erk1/2 activation and resulted in an activation of NFκB in an inflammatory milieu. Our findings suggest that fullerenols might counteract oxidative stress via the erk1/2 and NFκB pathways, and thus are able to protect microvascular endothelial cells under inflammatory conditions.
KW  - mouse brain microvascular endothelial cell cultur
KW  - adhesion molecules
KW  - fullerenes
KW  - blood-brain barrier
KW  - inflammation
KW  - tight junctions
Y1  - 2017
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-158072
SN  - 1422-0067
VL  - 18
IS  - 8
ER  - 
TY  - JOUR
A1  - Fehrholz, Markus
A1  - Seidenspinner, Silvia
A1  - Kunzmann, Steffen
T1  - Expression of surfactant protein B is dependent on cell density in H441 lung epithelial cells
JF  - PLoS ONE
N2  - Background
Expression of surfactant protein (SP)-B, which assures the structural stability of the pulmonary surfactant film, is influenced by various stimuli, including glucocorticoids; however, the role that cell-cell contact plays in SP-B transcription remains unknown. The aim of the current study was to investigate the impact of cell-cell contact on SP-B mRNA and mature SP-B expression in the lung epithelial cell line H441.

Methods
Different quantities of H441 cells per growth area were either left untreated or incubated with dexamethasone. The expression of SP-B, SP-B transcription factors, and tight junction proteins were determined by qPCR and immunoblotting. The influence of cell density on SP-B mRNA stability was investigated using the transcription inhibitor actinomycin D.

Results
SP-B mRNA and mature SP-B expression levels were significantly elevated in untreated and dexamethasone-treated H441 cells with increasing cell density. High cell density as a sole stimulus was found to barely have an impact on SP-B transcription factor and tight junction mRNA levels, while its stimulatory ability on SP-B mRNA expression could be mimicked using SP-B-negative cells. SP-B mRNA stability was significantly increased in high-density cells, but not by dexamethasone alone.

Conclusion
SP-B expression in H441 cells is dependent on cell-cell contact, which increases mRNA stability and thereby potentiates the glucocorticoid-mediated induction of transcription. Loss of cell integrity might contribute to reduced SP-B secretion in damaged lung cells via downregulation of SP-B transcription. Cell density-mediated effects should thus receive greater attention in future cell culture-based research.
KW  - messenger RNA
KW  - surfactants
KW  - epithelial cells
KW  - transcription factors
KW  - gene expression
KW  - tight junctions
KW  - adenocarcinoma of the lung
KW  - immunoblotting
Y1  - 2017
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-158291
VL  - 12
IS  - 9
ER  -