Effects of wortmannin on phosphorylation of PDK1, GSK3-beta, PTEN and expression of Skp2 mRNA after ischemia/reperfusion injury in the mouse kidney.
OBJECTIVE
The aim of this study was to investigate the role of 3-phosphoinositide-dependent protein kinase-1 (PDK1), glycogen synthase kinase-3beta (GSK3-beta) and phosphatase and tensin homologue deleted on chromosome 10 (PTEN), which are the components of the phosphoinositide 3-kinase (PI3K)/Akt pathway, and expression of S-phase kinase-associated protein 2 (Skp2) messenger RNA (mRNA) in renal ischemia/reperfusion.


METHODS
Three experimental groups, sham-operative mice, vehicle-delivered mice and wortmannin-treated ischemia/reperfusion injury (IRI) mice were designed to examine PDK1, GSK3-beta and PTEN phosphorylation status, as well as expression of Skp2 mRNA at 30 min, 90 min, 24 h and 48 h of reperfusion after ischemia treatment. Wortmannin or its vehicle was given intraperitoneally 4 h before surgery. Expression of Skp2 mRNA was examined by semiquantitative reverse-transcription PCR, and the components of the PI3K/Akt pathway were detected by western blotting in the IRI kidney.


RESULTS
Phosphorylation of PDK1(Ser241), GSK3-beta(Ser9) and PTEN(Ser380) was increased after ischemia/reperfusion in the mouse kidney, and phosphorylation of PDK1 was reduced by wortmannin administration. The renal Skp2 mRNA increased after IRI in mouse, which could be inhibited by wortmannin.


CONCLUSIONS
Our primary study suggests that the PI3K/Akt signaling pathway plays an important role in regulating the repair following renal IRI. The Skp2 mRNA increased in the IRI kidney and may be regulated by the PI3K/Akt pathway.
Zheng
Xiangyi
X
Department of Urology, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310003, Zhejiang, China.
Xie
Liping
L
Qin
Jie
J
Shen
Huafeng
H
Chen
Zhaodian
Z
Jin
Yongfeng
Y
D019870:1-Phosphatidylinositol 4-Kinase / Q000378:metabolism; D064413:3-Phosphoinositide-Dependent Protein Kinases; D000730:Androstadienes / Q000494:pharmacology*; D000818:Animals; D004195:Disease Models, Animal; D015870:Gene Expression / Q000187:drug effects; D038362:Glycogen Synthase Kinase 3 / Q000378:metabolism; D000071679:Glycogen Synthase Kinase 3 beta; D007668:Kidney / Q000098:blood supply*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D051059:PTEN Phosphohydrolase / Q000378:metabolism; D010726:Phosphodiesterase Inhibitors / Q000494:pharmacology*; D010766:Phosphorylation / Q000187:drug effects; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D011897:Random Allocation; D015427:Reperfusion Injury / Q000378:metabolism*; D044786:S-Phase Kinase-Associated Proteins / Q000235:genetics / Q000378:metabolism; D013997:Time Factors; D016896:Treatment Outcome; D000077191:Wortmannin
D000730:Androstadienes; D010726:Phosphodiesterase Inhibitors; D012333:RNA, Messenger; D044786:S-Phase Kinase-Associated Proteins; D019870:1-Phosphatidylinositol 4-Kinase; D064413:3-Phosphoinositide-Dependent Protein Kinases; D000071679:Glycogen Synthase Kinase 3 beta; C000605507:Gsk3b protein, mouse; C578564:Pdpk1 protein, mouse; D017346:Protein Serine-Threonine Kinases; D038362:Glycogen Synthase Kinase 3; D051059:PTEN Phosphohydrolase; D000077191:Wortmannin