Event:264

From AOP-Wiki
Jump to: navigation, search



Event Title

SREBP-1c, Activation
Short name: SREBP-1c, Activation

Key Event Overview

Please follow link to widget page to edit this section.

If you manually enter text in this section, it will get automatically altered or deleted in subsequent edits using the widgets.

AOPs Including This Key Event

AOP Name Event Type Essentiality
LXR activation leading to hepatic steatosis KE

Taxonomic Applicability

Name Scientific Name Evidence Links

Level of Biological Organization

Biological Organization

How this Key Event works

An increase on the mRNA of the SREBP-1c is responsible for an increase of the mRNA of lipogenic enzymes like acetyl-CoA carboxylase (ACC) and fatty acid synthase (FAS) (Foretz et al. 1999, Foretz et al. 2000). This finding is demonstrated from the absence of triglyceride accumulation on SREBP-1c (-/-) mice [1], [2], [3], [4].

However there is evidence that this effect is not induced in the embryonic state indicating a different role of the SREBP-1c between embryonic and adult life [5]. It is also suggested that for lipogenic genes, SREBP-1c acts together with ChREBP [6]. In addition, in STZ diabetic mice, adenovirus-mediated over-expression of SREBP-1c in the liver resulted in an increase of lipogenic enzyme expression with an increase of the triglyceride hepatic content and a marked decrease in the hyperglycaemia of diabetic mice mimicking perfectly the effect of an insulin injection [7].

Finally there are a number of studies that demonstrated that SREBP-1c is essential for glucokinase (GK) expression and that it is a mediator of insulin action [8], [9].

How it is Measured or Detected

Methods that have been previously reviewed and approved by a recognized authority should be included in the Overview section above. All other methods, including those well established in the published literature, should be described here. Consider the following criteria when describing each method: 1. Is the assay fit for purpose? 2. Is the assay directly or indirectly (i.e. a surrogate) related to a key event relevant to the final adverse effect in question? 3. Is the assay repeatable? 4. Is the assay reproducible?

Evidence Supporting Taxonomic Applicability

References

  1. Liang et al. 2002
  2. Schultz et al. 2000
  3. Horton et al. 2002
  4. Shimano et al. 1999
  5. Liang et al. 2002
  6. Ishii et al. 2004
  7. Bécard et al. 2001
  8. Ferre 2007
  9. Fleischmann 1999