Search results for "Insulin receptor substrate"
showing 5 items of 15 documents
Genetic and environmental aspect of polycystic ovary syndrome.
2004
Polycystic ovary syndrome (PCOS) is a heterogeneous syndrome determined in most patients by the association of two main factors: hyperandrogenism and insulin resistance. These characters are probably independent of each other and seem to be inherited by several different mechanisms. In some patients homozygous gene alteration has been found but in most patients PCOS seems to be determined by the association of gene polymorphisms that are common in the general population but alone are unable to determine phenotypic consequences. Alteration of genes that regulate the initial steps of ovarian steroidogenesis is probably the main causal factor of hyperandrogenism. Insulin resistance may be the …
The estrogen receptor α:insulin receptor substrate 1 complex in breast cancer: structure–function relationships
2007
Background: Insulin receptor substrate 1 (IRS-1) is a signaling molecule that exerts a key role in mediating cross talk between estrogen receptor a (ERa) and insulin-like growth factor 1 (IGF-1) in breast cancer cells. Previously, we demonstrated that a fraction of IRS-1 binds ERa, translocates to the nucleus, and modulates ERa-dependent transcription at estrogen response elements (ERE). Here, we studied structure-function relationships of the ER-a:IRS-1 complex under IGF-1 and/or estradiol (E 2 ) stimulation. Materials and methods: ERa and IRS-1 deletion mutants were used to analyze structural and functional ERα/IRS-1 interactions. IRS-1 binding to ERE and IRS-1 role in ERa-dependent ERE t…
IRS-2 deficiency impairs NMDA receptor-dependent long-term potentiation
2011
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License.-- et al.
Role of insulin-like growth factors in autocrine growth of human retinoblastoma Y79 cells.
1996
In this study, we have demonstrated that human retinoblastoma Y79 cells produce insulin-like growth factors (IGFs) type I and type II and release them into the medium. We have also ascertained, by means of competitive studies and cross-linking procedure, that Y79 cells contain the type-I IGF receptor (IGF-IR). Furthermore, surface-bound IGF-I is internalised by the receptor, then degraded to amino acids. Insulin, IGF-I and IGF-II caused down-regulation of IGF-IR; the effect is concentration and time dependant. Scatchard analysis demonstrated that incubation with insulin markedly decreased the binding capacity measured for IGF-I while the apparent Kd value calculated for IGF-I binding was no…
Increased dosage of Ink4/Arf protects against glucose intolerance and insulin resistance associated with aging
2013
Recent genome-wide association studies have linked type-2 diabetes mellitus to a genomic region in chromosome 9p21 near the Ink4/Arf locus, which encodes tumor suppressors that are up-regulated in a variety of mammalian organs during aging. However, it is unclear whether the susceptibility to type-2 diabetes is associated with altered expression of the Ink4/Arf locus. In the present study, we investigated the role of Ink4/Arf in age-dependent alterations of insulin and glucose homeostasis using Super-Ink4/Arf mice which bear an extra copy of the entire Ink4/Arf locus. We find that, in contrast to age-matched wild-type controls, Super-Ink4/Arf mice do not develop glucose intolerance with agi…