TY - JOUR
T1 - Intrinsic activation of PI3K/Akt signaling pathway and its neuroprotective effect against retinal injury
AU - Nakazawa, Toru
AU - Shimura, Masahiko
AU - Tomita, Hiroshi
AU - Akiyama, Hiroshi
AU - Yoshioka, Yuki
AU - Kudou, Hideyo
AU - Tamai, Makoto
N1 - Funding Information:
This work is supported in part by grant-in-aid for Developmental Scientific Research (B) for MT (No. 10307041) and for HT (No. 1177103) of Ministry of Education, Science and Culture of Japan. The authors would like to thank Dr. Duco I. Hamasaki of the Bascom Palmer Eye Institute, University of Miami for editing the manuscript, and Fukuda Y, Sawai H, Inoue T (Osaka University, Osaka, Japan), and Watanabe M (Aichi, Japan) for technical support of counting fluoro-gold labeled RGCs.
PY - 2003/1
Y1 - 2003/1
N2 - Purpose. The aim of this study was to determine whether the phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway can function as a neuroprotective pathway following induced retinal injury. Methods. The activation of Akt was assessed by immunoblot analysis, and the role of PI3K/Akt pathway was evaluated by TUNEL staining and counting the number of retrogradely-labeled retinal ganglion cells (RGCs) in the whole retina at 168 h after injury with or without PI3K specific inhibitor, LY294002. Results. Akt was induced within one hr and reached a maximum 6hrs after optic nerve clamping. The activation was observed in the RGC layer including RGCs, the inner plexiform layer, inner nuclear layer, and in the photoreceptor outer segments. The number of surviving RGCs was decreased significantly 168 hrs after injury. LY294002 partially inhibited the activation of Akt, and significantly decreased the number of surviving RGCs as compared with that of injury alone. Conclusions. These results indicate that the PI3K/Akt signaling pathway is activated intrinsically and has a neuroprotective effect on injured RGCs.
AB - Purpose. The aim of this study was to determine whether the phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway can function as a neuroprotective pathway following induced retinal injury. Methods. The activation of Akt was assessed by immunoblot analysis, and the role of PI3K/Akt pathway was evaluated by TUNEL staining and counting the number of retrogradely-labeled retinal ganglion cells (RGCs) in the whole retina at 168 h after injury with or without PI3K specific inhibitor, LY294002. Results. Akt was induced within one hr and reached a maximum 6hrs after optic nerve clamping. The activation was observed in the RGC layer including RGCs, the inner plexiform layer, inner nuclear layer, and in the photoreceptor outer segments. The number of surviving RGCs was decreased significantly 168 hrs after injury. LY294002 partially inhibited the activation of Akt, and significantly decreased the number of surviving RGCs as compared with that of injury alone. Conclusions. These results indicate that the PI3K/Akt signaling pathway is activated intrinsically and has a neuroprotective effect on injured RGCs.
KW - Damage
KW - Phosphorylation
KW - Retinal ganglion cell
KW - Signal transduction
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U2 - 10.1076/ceyr.26.1.55.14254
DO - 10.1076/ceyr.26.1.55.14254
M3 - Article
C2 - 12789537
AN - SCOPUS:0042266463
VL - 26
SP - 55
EP - 63
JO - Current Eye Research
JF - Current Eye Research
SN - 0271-3683
IS - 1
ER -