Cited by 349Metabolism, Diabetes, and CancerAdipokines, Inflammation, and Metabolic DiseasesEstrogen and related hormone effects

Modulation of insulin receptor, insulin receptor substrate-1, and phosphatidylinositol 3-kinase in liver and muscle of dexamethasone-treated rats.

Open access
Saad, M J, Folli, F, Kahn, J A, Kahn, C R·1993·Journal of Clinical Investigation

Abstract

Insulin rapidly stimulates tyrosine kinase activity of its receptor resulting in phosphorylation of its cytosolic substrate, insulin receptor substrate-1 (IRS-1), which in turn associates with phosphatidylinositol 3-kinase (PI 3-kinase), thus activating the enzyme. Glucocorticoid treatment is known to produce insulin resistance, but the exact molecular mechanism is unknown. In the present study we have examined the levels and phosphorylation state of the insulin receptor and IRS-1, as well as the association/activation between IRS-1 and PI 3-kinase in the liver and muscle of rats treated with dexamethasone. After dexamethasone treatment (1 mg/kg per d for 5 d), there was no change in insulin receptor concentration in liver of rats as determined by immunoblotting with antibody to the COOH-terminus of the receptor. However, insulin stimulation of receptor autophosphorylation determined by immunoblotting with antiphosphotyrosine antibody was reduced by 46.7 +/- 9.1%. IRS-1 and PI 3-kinase protein levels increased in liver of dexamethasone-treated animals by 73 and 25%, respectively (P < 0.05). By contrast, IRS-1 phosphorylation was decreased by 31.3 +/- 10.9% (P < 0.05), and insulin stimulated PI 3-kinase activity in anti-IRS-1 immunoprecipitates was decreased by 79.5 +/- 11.2% (P < 0.02). In muscle, the changes were less dramatic, and often in opposite direction of those observed in liver. Thus, there was no significant change in insulin receptor level or phosphorylation after dexamethasone treatment. IRS-1 and PI 3-kinase levels were decreased to 38.6 and 65.6%, respectively (P < 0.01 and P < 0.05). IRS-1 phosphorylation showed no significant change in muscle, but insulin-stimulated IRS-1 associated PI 3-kinase was decreased by 41%. Thus, dexamethasone has differential effects on the proteins involved in the early steps in insulin action in liver and muscle. In both tissues, dexamethasone treatment results in a reduction in insulin-stimulated IRS-1-associated P I3-kinase, which may play a role in the pathogenesis of insulin resistance at the cellular level in these animals.

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Integrity signals

Registry

Crossref · 10.1172/jci116803

Cites

46 of 46 references verified0 citation errors · 0 not checkable

Statistics

Claims the paper makes

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

The self-check needs the paper’s full text.

Cites

Flagged first, then by citations

Cited by

Sorted by citations

Authors
Saad, M. J., Folli, F., Kahn, J. A., & Kahn, C. R.
Affiliations
  • Joslin Diabetes Center (US)
  • Brigham and Women's Hospital (US)
Venue
Journal of Clinical Investigation
Published
1993-10-01
Volume
92
Issue
4
Pages
2065-2072
ISSN
0021-9738 (ISSN-L)
OpenAlex
W1986519087
Cited by
349
References
42
Citations by year
2026: 3 · 2025: 3 · 2024: 5 · 2023: 8 · 2022: 10 · 2021: 9 · 2020: 14 · 2019: 2 · 2018: 11 · 2017: 10 · 2016: 14 · 2015: 9 · 2014: 15 · 2013: 12 · 2012: 12
FWCI
2.57
Type
journal article
Language
en
Open access
Locations
  • Journal of Clinical Investigation (publishedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
  • Archivio Istituzionale della Ricerca (Universita Degli Studi Di Milano) (submittedVersion, other-oa)
Funders
  • Joslin Diabetes Center
  • Conselho Nacional de Desenvolvimento Científico e Tecnológico
  • National Institutes of Health (DK 36836)
  • National Institute of Diabetes and Digestive and Kidney Diseases (DK 33201, DK36836, R01DK033201, P30DK036836)
Topics
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Metabolism, Diabetes, and Cancer
  • Health Sciences › Medicine › Epidemiology › Adipokines, Inflammation, and Metabolic Diseases
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Genetics › Estrogen and related hormone effects
Keywords
insulin resistance, glucocorticoids, dexamethasone, insulin receptor, IRS-1, phosphatidylinositol 3-kinase, insulin receptor autophosphorylation, IRS-1 phosphorylation, liver, skeletal muscle, insulin signaling, insulin receptor tyrosine kinase, tissue-specific effects, rats, enzyme activity
MeSH terms
Amino Acid Sequence, Animals, Antibodies, Dexamethasone, Insulin, Kinetics, Liver, Male, Molecular Sequence Data, Muscles, Peptides, Phosphoproteins, Phosphorylation, Receptor, Insulin, Tyrosine, Immunoblotting, Phosphotransferases (Alcohol Group Acceptor), Phosphotyrosine, Phosphatidylinositol 3-Kinases, Rats, Insulin Receptor Substrate Proteins

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

Are you an author, or do you see a problem with this page? Request a review