TY - JOUR
T1 - The immunoproteasome β5i subunit is a key contributor to ictogenesis in a rat model of chronic epilepsy
AU - Mishto, Michele
AU - Raza, Muhammad L.
AU - de Biase, Dario
AU - Ravizza, Teresa
AU - Vasuri, Francesco
AU - Martucci, Morena
AU - Keller, Christin
AU - Bellavista, Elena
AU - Buchholz, Tonia J.
AU - Kloetzel, Peter M.
AU - Pession, Annalisa
AU - Vezzani, Annamaria
AU - Heinemann, Uwe
PY - 2015/10/1
Y1 - 2015/10/1
N2 - The proteasome is the core of the ubiquitin-proteasome system and is involved in synaptic protein metabolism. The incorporation of three inducible immuno-subunits into the proteasome results in the generation of the so-called immunoproteasome, which is endowed of pathophysiological functions related to immunity and inflammation. In healthy human brain, the expression of the key catalytic β5i subunit of the immunoproteasome is almost absent, while it is induced in the epileptogenic foci surgically resected from patients with pharmaco-resistant seizures, including temporal lobe epilepsy.We show here that the β5i immuno-subunit is induced in experimental epilepsy, and its selective pharmacological inhibition significantly prevents, or delays, 4-aminopyridine-induced seizure-like events in acute rat hippocampal/entorhinal cortex slices. These effects are stronger in slices from epileptic vs normal rats, likely due to the more prominent β5i subunit expression in neurons and glia cells of diseased tissue. β5i subunit is transcriptionally induced in epileptogenic tissue likely by Toll-like receptor 4 signaling activation, and independently on promoter methylation.The recent availability of selective β5i subunit inhibitors opens up novel therapeutic opportunities for seizure inhibition in drug-resistant epilepsies.
AB - The proteasome is the core of the ubiquitin-proteasome system and is involved in synaptic protein metabolism. The incorporation of three inducible immuno-subunits into the proteasome results in the generation of the so-called immunoproteasome, which is endowed of pathophysiological functions related to immunity and inflammation. In healthy human brain, the expression of the key catalytic β5i subunit of the immunoproteasome is almost absent, while it is induced in the epileptogenic foci surgically resected from patients with pharmaco-resistant seizures, including temporal lobe epilepsy.We show here that the β5i immuno-subunit is induced in experimental epilepsy, and its selective pharmacological inhibition significantly prevents, or delays, 4-aminopyridine-induced seizure-like events in acute rat hippocampal/entorhinal cortex slices. These effects are stronger in slices from epileptic vs normal rats, likely due to the more prominent β5i subunit expression in neurons and glia cells of diseased tissue. β5i subunit is transcriptionally induced in epileptogenic tissue likely by Toll-like receptor 4 signaling activation, and independently on promoter methylation.The recent availability of selective β5i subunit inhibitors opens up novel therapeutic opportunities for seizure inhibition in drug-resistant epilepsies.
KW - Neuroinflammation
KW - Pharmaco-resistant seizures
KW - Pilocarpine
KW - Proteasome inhibitors
UR - http://www.scopus.com/inward/record.url?scp=84940606835&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84940606835&partnerID=8YFLogxK
U2 - 10.1016/j.bbi.2015.05.007
DO - 10.1016/j.bbi.2015.05.007
M3 - Article
C2 - 26044087
AN - SCOPUS:84940606835
VL - 49
SP - 188
EP - 196
JO - Brain, Behavior, and Immunity
JF - Brain, Behavior, and Immunity
SN - 0889-1591
ER -