Activation of signal transducer and activator of transcription 3 in rat liver after heat shock and reperfusion stress.
Changes in transcription factors (TFs) accompany many types of cell stresses. By using electrophoretic mobility assays we show that the DNA binding of signal transducer and activator of transcription 3 (STAT3) is activated in rat liver by heat shock and ischemia-reperfusion. Northern blot and Western blot analysis reveal an increase of the mRNA and protein level of this transcription factor. Under both conditions the phosphorylation of pre-existing STAT3 is prompt and precedes the increase in the STAT3 protein. The activation: (1) is functional, i.e. is followed by the transcription of the target gene alpha(1)-acid glycoprotein (2) is strongly inhibited by pretreatment with the interleukin-1 receptor antagonist before heat shock but only slightly by pretreatment before ischemia-reperfusion (3) might, at least in part, be mediated by a cytokine cascade involving also interleukin-6. These results are consistent with the hypothesis that different kinds of stress can activate a number of common TFs.
Tacchini
Lorenza
L
Istituto di Patologia Generale dell'Università degli Studi di Milano, Centro di Studio sulla Patologia Cellulare del CNR, via Mangiagalli 31, 20133 Milan, Italy.
Fusar-Poli
Daniela
D
Sironi
Marina
M
Mantovani
Alberto
A
Bernelli-Zazzera
Aldo
A
D000818:Animals; D015152:Blotting, Northern; D015153:Blotting, Western; D004268:DNA-Binding Proteins / Q000378:metabolism*; D003720:Densitometry; D006358:Hot Temperature; D015151:Immunoblotting; D015850:Interleukin-6 / Q000097:blood / Q000378:metabolism; D008099:Liver / Q000378:metabolism*; D008297:Male; D009841:Oligonucleotides / Q000737:chemistry; D018384:Oxidative Stress; D010766:Phosphorylation; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D015424:Reperfusion; D050796:STAT3 Transcription Factor; D013997:Time Factors; D015534:Trans-Activators / Q000378:metabolism*
D004268:DNA-Binding Proteins; D015850:Interleukin-6; D009841:Oligonucleotides; D012333:RNA, Messenger; D050796:STAT3 Transcription Factor; C494088:Stat3 protein, rat; D015534:Trans-Activators