Linked Life Data

15982852

Source:http://linkedlifedata.com/resource/pubmed/id/15982852

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2005-10-31
pubmed:abstractText
Hematopoietic cytokines, including interleukin (IL)-3 and erythropoietin (Epo), regulate hematopoiesis by stimulating their receptors coupled with the Jak2 tyrosine kinase to induce receptor tyrosine phosphorylation and activate mainly the STAT5, PI3K/Akt, and Ras/MEK/ERK signaling pathways. Here we demonstrate that IL-3 or Epo induces a rapid and transient (peaking at 30 min) as well as late progressive increase in reactive oxygen species (ROS) in a hematopoietic progenitor model cell line, 32Dcl3, and its subclone expressing the Epo receptor (EpoR), 32D/EpoR-Wt. The cytokine-induced ROS generation was not affected in 32Dcl3 cells depleted of mitochondrial DNA. The antioxidant N-acetyl-L-cysteine (NAC) inhibited IL-3-induced tyrosine phosphorylation of Jak2, IL-3 receptor betac subunit (IL-3Rbetac), and STAT5 as well as activation-specific phosphorylation of Akt, MEK, and ERK, while treatment of cells with H2O2 activated these signaling events. NAC also inhibited the EpoR-induced transphosphorylation of IL-3Rbetac. Moreover, NAC treatment reduced the expression levels of c-Myc, Cyclin D2, and Cyclin E, and induced expression of p27, thus inhibiting the G1 to S phase transition of cells cultured with IL-3. Further studies have shown that the degradation of c-Myc was facilitated or inhibited by treatment of cells with NAC or H2O2, respectively. These data indicate that the rapid generation of ROS by cytokine stimulation, which is at least partly independent of mitochondria, may play a role in activation of Jak2 and the STAT5, PI3K/Akt, and Ras/MEK/ERK signaling pathways as well as in transactivation of cytokine receptors. The cytokine-induced ROS generation was also implicated in G1 to S progression, possibly through stabilization of c-Myc and induction of G1 phase Cyclin expression leading to suppression of p27.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0898-6568
pubmed:author
pubmed:issnType
Print
pubmed:volume
18
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
174-82
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
Reactive oxygen species generated by hematopoietic cytokines play roles in activation of receptor-mediated signaling and in cell cycle progression.
pubmed:affiliation
Department of Hematology, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't