TY  - JOUR
A1  - Albert-Weissenberger, Christiane
A1  - Stetter, Christian
A1  - Meuth, Sven G.
A1  - Göbel, Kerstin
A1  - Bader, Michael
A1  - Sirén, Anna-Leena
A1  - Kleinschnitz, Christoph
T1  - Blocking of Bradykinin Receptor B1 Protects from Focal Closed Head Injury in Mice by Reducing Axonal Damage and Astroglia Activation
JF  - Journal of Cerebral Blood Flow and Metabolism
N2  - The two bradykinin receptors B1R and B2R are central components of the kallikrein–kinin system with different expression kinetics and binding characteristics. Activation of these receptors by kinins triggers inflammatory responses in the target organ and in most situations enhances tissue damage. We could recently show that blocking of B1R, but not B2R, protects from cortical cryolesion by reducing inflammation and edema formation. In the present study, we investigated the role of B1R and B2R in a closed head model of focal traumatic brain injury (TBI; weight drop). Increased expression of B1R in the injured hemispheres of wild-type mice was restricted to the later stages after brain trauma, i.e. day 7 (P<0.05), whereas no significant induction could be observed for the B2R (P>0.05). Mice lacking the B1R, but not the B2R, showed less functional deficits on day 3 (P<0.001) and day 7 (P<0.001) compared with controls. Pharmacological blocking of B1R in wild-type mice had similar effects. Reduced axonal injury and astroglia activation could be identified as underlying mechanisms, while inhibition of B1R had only little influence on the local inflammatory response in this model. Inhibition of B1R may become a novel strategy to counteract trauma-induced neurodegeneration.
KW  - R-715
KW  - kinin receptors
KW  - closed head injury
KW  - β-APP
KW  - astrocytes
KW  - TNF-α
Y1  - 2012
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-125903
VL  - 32
IS  - 9
ER  - 
TY  - JOUR
A1  - Ahmad, Ruhel
A1  - Wolber, Wanja
A1  - Eckardt, Sigrid
A1  - Koch, Philipp
A1  - Schmitt, Jessica
A1  - Semechkin, Ruslan
A1  - Geis, Christian
A1  - Heckmann, Manfred
A1  - Brüstle, Oliver
A1  - McLaughlin, John K.
A1  - Sirén, Anna-Leena
A1  - Müller, Albrecht M.
T1  - Functional Neuronal Cells Generated by Human Parthenogenetic Stem Cells
JF  - PLoS One
N2  - Parent of origin imprints on the genome have been implicated in the regulation of neural cell type differentiation. The ability of human parthenogenetic (PG) embryonic stem cells (hpESCs) to undergo neural lineage and cell type-specific differentiation is undefined. We determined the potential of hpESCs to differentiate into various neural subtypes. Concurrently, we examined DNA methylation and expression status of imprinted genes. Under culture conditions promoting neural differentiation, hpESC-derived neural stem cells (hpNSCs) gave rise to glia and neuron-like cells that expressed subtype-specific markers and generated action potentials. Analysis of imprinting in hpESCs and in hpNSCs revealed that maternal-specific gene expression patterns and imprinting marks were generally maintained in PG cells upon differentiation. Our results demonstrate that despite the lack of a paternal genome, hpESCs generate proliferating NSCs that are capable of differentiation into physiologically functional neuron-like cells and maintain allele-specific expression of imprinted genes. Thus, hpESCs can serve as a model to study the role of maternal and paternal genomes in neural development and to better understand imprinting-associated brain diseases.
KW  - methylation
KW  - derivation
KW  - blastocysts
KW  - pluripotent
KW  - differentiation
KW  - lines
KW  - brain development
KW  - in-vitro
KW  - mice
KW  - specification
Y1  - 2012
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-130268
VL  - 7
IS  - 8
ER  -