Regulation of IGFBP-4 levels in human intestinal muscle by an IGF-I-activated, confluence-dependent protease.

@article{Kuemmerle2000RegulationOI,
  title={Regulation of IGFBP-4 levels in human intestinal muscle by an IGF-I-activated, confluence-dependent protease.},
  author={John F Kuemmerle and B Q Teng},
  journal={American journal of physiology. Gastrointestinal and liver physiology},
  year={2000},
  volume={279 5},
  pages={
          G975-82
        }
}
  • J. Kuemmerle, B. Teng
  • Published 1 November 2000
  • Biology, Medicine
  • American journal of physiology. Gastrointestinal and liver physiology
Human intestinal smooth muscle cells in culture produce insulin-like growth factor-I (IGF-I), IGF binding protein-3 (IGFBP-3), IGFBP-4, and IGFBP-5, which can modulate the effects of IGF-I on growth. This study examined the role of IGFBP-4 on IGF-I-induced growth and the mechanisms regulating IGFBP-4 levels. IGFBP-4 inhibited IGF-I-induced [(3)H]thymidine incorporation. IGFBP-4 mRNA levels were not altered by IGF-I. IGF-I caused a concentration-dependent activation of an endogenous IGFBP-4… 
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TLDR
It is concluded that endogenous IGFBP-3 directly inhibits proliferation of human intestinal smooth muscle cells by activation of TGF-betaRI and Smad2, an effect that is independent of its effect on IGF-I-stimulated growth.
Functional analysis of insulin-like growth factor binding protein -4 and -6 in transgenic mice
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It is revealed that overexpression of IGFBP-4 had no significant effect on the postnatal body and organ growth, except that the weight and volume of thymus in 8- and 12-week-old transgenic mice were significantly reduced compared to the controls.
Endogenous IGF-I protects human intestinal smooth muscle cells from apoptosis by regulation of GSK-3 beta activity.
  • J. Kuemmerle
  • Biology, Medicine
    American journal of physiology. Gastrointestinal and liver physiology
  • 2005
TLDR
It is concluded that endogenous IGF-I exerts two distinct but complementary effects on intestinal smooth muscle cell growth: it stimulates proliferation and inhibits apoptosis.
Insulin-like growth factor binding protein-4 expression is dependent on the carbohydrate in the media in HT-29 cells.
The role of the insulin-like growth factor system in colorectal cancer: review of current knowledge
TLDR
The current knowledge about the link between IGFs and colon cancer is mainly based on in vitro investigations, and further in vivo study is needed to understand the exact role of the IGF system, especially its binding proteins, so that they can be manipulated for the prevention and treatment of colorectal cancer.
IGF-binding protein-4: biochemical characteristics and functional consequences.
TLDR
The available data regarding the following aspects of IGFBP-4 are summarized: genomic organization, protein structure-function relationship, expression and its regulation, as well as IGF-dependent and -independent actions.
IGF-I elicits growth of human intestinal smooth muscle cells by activation of PI3K, PDK-1, and p70S6 kinase.
  • J. Kuemmerle
  • Biology, Computer Science
    American journal of physiology. Gastrointestinal and liver physiology
  • 2003
TLDR
Transfection of muscle cells with kinase-inactive Akt1(K179M) showed that these events were not required for IGF-I to activate p70S6 kinase and stimulate proliferation of human intestinal muscle cells.
Blunted satellite cell response is associated with dysregulated IGF-1 expression after exercise with age
TLDR
The greater muscle-specific expression of IGF-1 family members with a blunted post-exercise SC expression may be a compensatory attempt to rescue age-related anabolic resistance.
Insulin-like growth factors in the gastrointestinal tract and liver.
  • J. Kuemmerle
  • Medicine, Biology
    Endocrinology and metabolism clinics of North America
  • 2012
The insulin-like growth factor system and colorectal cancer: clinical and experimental evidence
ObjectiveThe aim of this review is to clarify the involvement of the insulinlike growth factor (IGF) system in the development of colorectal malignancy.Materials and methodsMedline searches were used…
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References

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  • J. Kuemmerle
  • Biology, Medicine
    American journal of physiology. Gastrointestinal and liver physiology
  • 2000
TLDR
Ex vivo regulation of IGFBP production by endogenous IGF-I is mediated by activation of distinct MAP kinase and PI 3-kinase pathways, the same pathways through which IGF- I stimulates growth.
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TLDR
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TLDR
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TLDR
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TLDR
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