Astrocytic expressions of phosphorylated Akt, GSK3beta and CREB following an excitotoxic lesion in the mouse hippocampus.
Glycogen synthase kinase 3beta (GSK3beta) is believed to play important roles in the regulation of synaptic plasticity, cell survival and circadian rhythms in the mature CNS. However, although several studies have been focused on the GSK3beta, little is known about GSK3beta changes in glial cells under neuropathological conditions. In this study, we evaluated the expressions of molecules associated with the GSK3beta signaling pathway, following the induction of an excitotoxic lesion in mouse brain by kainic acid (KA) injection, which caused pyramidal cell degeneration in the hippocampal CA3 region. In injured hippocampi, Ser47-Akt (protein kinase B, PKB) phosphorylation increased from 4 h until 1 day post-injection (PI). Ser9-GSK3beta and Ser133-cAMP responsive element-binding protein (CREB) phosphorylations showed similar spatiotemporal patterns in hippocampi at 1 day until 3 days PI. Double immunohistochemistry also showed that these phosphorylated forms of Akt, GSK3beta and CREB were expressed in astrocytes. For the first time, our data demonstrate the injury-induced astrocytic changes in the levels of phosphorylation of Akt, -GSK3beta and -CREB in vivo, which may reflect mechanisms of glial cells protection or adaptive response to damage.
Kim
Dong Woon
DW
Department of Anatomy, Chungnam National University College of Medicine, Daejeon 301-131, South Korea.
Lee
Jung Hoon
JH
Park
Sung Kyung
SK
Yang
Woo-Mi
WM
Jeon
Gye Sun
GS
Lee
Young Ho
YH
Chung
Chun Kee
CK
Cho
Sa Sun
SS
D000818:Animals; D001253:Astrocytes / Q000378:metabolism*; D015153:Blotting, Western; D017362:Cyclic AMP Response Element-Binding Protein / Q000096:biosynthesis*; D020869:Gene Expression Profiling; D038362:Glycogen Synthase Kinase 3 / Q000096:biosynthesis*; D000071679:Glycogen Synthase Kinase 3 beta; D006624:Hippocampus / Q000187:drug effects; D007608:Kainic Acid / Q000633:toxicity; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D010766:Phosphorylation; D051057:Proto-Oncogene Proteins c-akt / Q000096:biosynthesis*
D017362:Cyclic AMP Response Element-Binding Protein; D000071679:Glycogen Synthase Kinase 3 beta; C000605507:Gsk3b protein, mouse; D051057:Proto-Oncogene Proteins c-akt; D038362:Glycogen Synthase Kinase 3; D007608:Kainic Acid