Nuclear translocation of the transcription factor STAT5 in the rat brain after systemic leptin administration.
Leptin binding to its functional receptor stimulates JAK-STAT-signaling pathway, which finally results in activation and nuclear translocation of transcription factors of the signal transducer and activator of transcription (STAT) family, namely of STAT3. Here we report for the first time that systemic treatment with leptin (5 mg/kg; intraperitoneal injection) also increased the number of nuclear STAT5 signals in the hypothalamus. In particular, the entire arcuate nucleus (ARC), the ventral premammilary nucleus (PMV), and the supraoptic nucleus (SO) showed an enhanced nuclear STAT5 translocation in response to leptin when compared to saline, 120 min after the respective injection. Co-localization studies revealed that a high percentage of those STAT5-responsive cells proved to be neurons. In addition, some astrocytes within the ARC showed nuclear STAT5 signals. The functional relevance of leptin-induced nuclear STAT5 activation in hypothalamic cells still has to be determined.
Mütze
Jörg
J
Department of Veterinary-Physiology, Justus-Liebig-University Giessen, Frankfurter Strasse 100, D-35392 Giessen, Germany.
Roth
Joachim
J
Gerstberger
Rüdiger
R
Hübschle
Thomas
T
D021581:Active Transport, Cell Nucleus / Q000187:drug effects / Q000502:physiology; D000818:Animals; D001069:Appetite Regulation / Q000187:drug effects / Q000502:physiology; D001111:Arcuate Nucleus of Hypothalamus / Q000187:drug effects / Q000378:metabolism; D001253:Astrocytes / Q000187:drug effects / Q000378:metabolism; D001835:Body Weight / Q000187:drug effects / Q000502:physiology; D002467:Cell Nucleus / Q000187:drug effects / Q000378:metabolism*; D007031:Hypothalamus / Q000033:anatomy & histology / Q000187:drug effects / Q000378:metabolism*; D007274:Injections, Intraperitoneal; D020738:Leptin / Q000378:metabolism* / Q000494:pharmacology; D008297:Male; D009474:Neurons / Q000187:drug effects / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D050799:STAT5 Transcription Factor / Q000187:drug effects / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology; D013495:Supraoptic Nucleus / Q000187:drug effects / Q000378:metabolism
D020738:Leptin; D050799:STAT5 Transcription Factor