Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-2
pubmed:dateCreated
2002-9-30
pubmed:abstractText
Protein tyrosine phosphatase 1B (PTP1B) has recently been implicated in the regulation of body weight. A surprising phenotype of PTP1B-deficient mice is their resistance to diet-induced obesity. Since leptin is one of the primary hormones involved in the regulation of body weight and energy homeostasis, we investigated whether PTP1B affects leptin receptor (lepR) signaling directly. A mouse hypothalamic cell line, GT1-7, was established as a suitable cell model for the study of leptin signaling. Stimulation of GT1-7 cells by leptin caused tyrosine phosphorylation of endogenous STAT3 and activation of a STAT-dependent luciferase reporter gene. Over-expression of PTP1B in GT1-7 cells resulted in a dose-dependent decrease in endogenous JAK2 and STAT3 tyrosine phosphorylation compared with cells transfected with lepR alone. Consistent with inhibition of JAK-STAT signaling, PTP1B over-expression caused a dose-dependent decrease in leptin-induced, STAT-dependent luciferase reporter gene activation in GT1-7 cells. Furthermore, over-expression of PTP1B led to a decrease in mRNA accumulation of suppressor-of-cytokine-signalling-3 (SOCS3) and c-fos, genes that are acutely induced by leptin. Using gene microarray analysis, we confirmed that PTP1B reduces the level of gene expression of SOCS3 and showed that the expression level of other leptin-regulated genes was affected. Genes up-regulated by leptin were decreased in cells over-expressing PTP1B. Conversely, the expression of genes down-regulated by leptin was enhanced by PTP1B over-expression in GT1-7 cells. Our findings indicate that PTP1B is a negative regulator of leptin signaling and suggest that PTP1B inhibitors might be efficacious in the treatment of obesity by increasing leptin sensitivity.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/DNA-Binding Proteins, http://linkedlifedata.com/resource/pubmed/chemical/JAK2 protein, human, http://linkedlifedata.com/resource/pubmed/chemical/Jak2 protein, mouse, http://linkedlifedata.com/resource/pubmed/chemical/Janus Kinase 2, http://linkedlifedata.com/resource/pubmed/chemical/Leptin, http://linkedlifedata.com/resource/pubmed/chemical/PTPN1 protein, human, http://linkedlifedata.com/resource/pubmed/chemical/Protein Tyrosine Phosphatase..., http://linkedlifedata.com/resource/pubmed/chemical/Protein Tyrosine Phosphatases, http://linkedlifedata.com/resource/pubmed/chemical/Protein-Tyrosine Kinases, http://linkedlifedata.com/resource/pubmed/chemical/Proto-Oncogene Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Ptpn1 protein, mouse, http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Cell Surface, http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Leptin, http://linkedlifedata.com/resource/pubmed/chemical/STAT3 Transcription Factor, http://linkedlifedata.com/resource/pubmed/chemical/STAT3 protein, human, http://linkedlifedata.com/resource/pubmed/chemical/Stat3 protein, mouse, http://linkedlifedata.com/resource/pubmed/chemical/Trans-Activators, http://linkedlifedata.com/resource/pubmed/chemical/leptin receptor, human, http://linkedlifedata.com/resource/pubmed/chemical/leptin receptor, mouse
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0303-7207
pubmed:author
pubmed:issnType
Print
pubmed:day
30
pubmed:volume
195
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
109-18
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed-meshheading:12354677-Animals, pubmed-meshheading:12354677-Cell Line, pubmed-meshheading:12354677-DNA-Binding Proteins, pubmed-meshheading:12354677-Gene Expression Profiling, pubmed-meshheading:12354677-Gene Expression Regulation, pubmed-meshheading:12354677-Humans, pubmed-meshheading:12354677-Hypothalamus, pubmed-meshheading:12354677-Janus Kinase 2, pubmed-meshheading:12354677-Leptin, pubmed-meshheading:12354677-Mice, pubmed-meshheading:12354677-Phosphorylation, pubmed-meshheading:12354677-Protein Tyrosine Phosphatase, Non-Receptor Type 1, pubmed-meshheading:12354677-Protein Tyrosine Phosphatases, pubmed-meshheading:12354677-Protein-Tyrosine Kinases, pubmed-meshheading:12354677-Proto-Oncogene Proteins, pubmed-meshheading:12354677-Receptors, Cell Surface, pubmed-meshheading:12354677-Receptors, Leptin, pubmed-meshheading:12354677-STAT3 Transcription Factor, pubmed-meshheading:12354677-Signal Transduction, pubmed-meshheading:12354677-Trans-Activators, pubmed-meshheading:12354677-Transcriptional Activation, pubmed-meshheading:12354677-Transfection
pubmed:year
2002
pubmed:articleTitle
Protein tyrosine phosphatase 1B negatively regulates leptin signaling in a hypothalamic cell line.
pubmed:affiliation
Metabolic Disease Research, Global Pharmaceutical Products Division, Department 47R, Bldg AP10, 100 Abbott Park Road, Abott Park, IL 60064-6099, USA. wiweka.kaszubska@abbott.com
pubmed:publicationType
Journal Article