, 2007), thereby permitting serum albumin entry into the brain (van Vliet et al., 2007), followed by astrocytic albumin uptake (Ivens et al., 2007); and activation of endothelial and leukocytes interactions (Fabene et al., 2008; Kleen & Holmes, 2008; Ransohoff, 2009).
Bleomycin mouse However, despite this wealth of data, the mechanisms underlying enduring immune and inflammatory responses in temporal lobe epilepsy (TLE) remain largely elusive. As described in the current issue of EJN, Aronica et al. (2010) took an important step toward resolving this issue. They demonstrated the selective up-regulation of a proinflammatory signalling-associated microRNA (miRNA) in a rat model of TLE as well as in human TLE. MicroRNAs are genomically encoded small non-coding RNAs that influence the translation and stability of mRNAs (Zhao & Srivastava, 2007). Aronica et al. (2010) focused on miR-146a, a microRNA that is induced by pro-inflammatory stimuli, modulating innate immunity through regulation of Toll-like receptor signaling and cytokine responses (Taganov et al., 2006). miR-146a is also known to play a functional role in T lymphocyte-mediated immune responses (Curtale et al., 2010). In order to understand the regulation and function of miR-146a in epilepsy, Aronica
et al. (2010) investigated the dynamics of miR-146a expression during epileptogenesis in a rat model of TLE. Furthermore, they studied Trichostatin A cost the expression and cellular distribution of this microRNA in hippocampal tissue obtained from TLE patients with hippocampal sclerosis. The authors report an increase of miR-146a expression in the CA3 region of rats during latent and chronic phases of experimental epilepsy, as well as in the human tissue. It is important to note that miR-146a expression was evident not only in neurons, but most prominently in GFAP-positive reactive astrocytes, underscoring their key role for orchestrating inflammatory responses in epilepsy. The results of this study PI-1840 suggest new avenues toward the identification of cellular mechanisms underlying epileptogenesis and persistent functional alterations in chronic epilepsy.
Furthermore, these results indicate that miRNAs, linking astrocytes with inflammatory mechanisms, are potentially promising new cellular targets for the development of antiepileptic drugs. “
“Cell therapy for spinal cord injury (SCI) is a promising strategy for clinical application. Both bone marrow mesenchymal stromal cells (MSCs; also known as bone marrow-derived ‘mesenchymal stem cells’) and olfactory ensheathing cells (OECs) have demonstrated beneficial effects following transplantation in animal models of SCI. However, due to the large number of affecting parameters that determine the therapy success and the lack of methodological consensus, the comparison of different works is difficult. Therefore, we compared the effects of MSC and OEC transplants at early or delayed time after a spinal cord contusion injury in the rat.