Linked Life Data

1389231

Source:http://linkedlifedata.com/resource/pubmed/id/1389231

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1992-10-26
pubmed:abstractText
The role of growth hormone (GH) in the differentiation process of Ob1771 mouse preadipocyte cells has been studied under culture conditions that were serum-free and hormone-supplemented and which were previously shown to lead to terminal differentiation. In the absence of GH, a dramatic decrease in the adipogenic activity of the culture medium could be observed, as indicated 12 days after confluence by the low levels of glycerol-3-phosphate dehydrogenase activity and the sharp reduction of the number of triacylglycerol-containing cells. This decrease in adipogenic activity was accompanied by a parallel loss of the mitogenic potency of the culture medium. Determination of the half-maximal and maximal concentrations of GH required for the restoration of growth and differentiation were identical, 0.5 and 2 nM, respectively. Despite the presence of insulin-like growth factor-I (IGF-I) to substitute for supraphysiological concentrations of insulin and to saturate IGF-I receptor, GH was still required to induce terminal differentiation of a maximal number of cells. However, protein kinase C activators such as prostaglandin F2 alpha, phorbol esters and diacylglycerol were able to mimic GH in promoting a maximal mitogenic-adipogenic response, indicating that the ability of GH to induce diacylglycerol production (Doglio et al., 1989; Catalioto et al., 1990) plays a prominent role in this process. Furthermore, in agreement with the fact that the mitoses which precede terminal differentiation of Ob1771 preadipocytes are strictly controlled by cAMP and only modulated by protein kinase C, terminal differentiation of Ob1771 preadipocytes occurred in the absence of GH upon supplementation with high concentrations of carbaprostacyclin, added as a cAMP-elevating agent or with 8-Br-cAMP, added as a cAMP analogue. It is concluded that the control exerted by GH on terminal differentiation of mouse preadipocytes corresponds to a modulating mitogenic effect mediated through protein kinase C activation and leading to a potentiation of the cAMP and IGF-I mitogenic signalling pathways.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0897-7194
pubmed:author
pubmed:issnType
Print
pubmed:volume
6
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
255-64
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1992
pubmed:articleTitle
Terminal differentiation of mouse preadipocyte cells: the mitogenic-adipogenic role of growth hormone is mediated by the protein kinase C signalling pathway.
pubmed:affiliation
Centre de Biochimie du CNRS (UMR 134), U.F.R. Sciences, Laboratoire de Biologie du Développement du Tissu Adipeux, Université de Nice-Sophia Antipolis, France.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't