In:
Science Translational Medicine, American Association for the Advancement of Science (AAAS), Vol. 11, No. 513 ( 2019-10-09)
Abstract:
The impact of liver disease on whole-body glucose homeostasis is largely attributed to dysregulated release of secretory proteins in response to metabolic stress. The molecular cues linking liver to whole-body glucose metabolism remain elusive. We found that expression of G protein α-13 (Gα 13 ) was decreased in the liver of mice and humans with diabetes. Liver-specific deletion of the Gna13 gene in mice resulted in systemic glucose intolerance. Comparative secretome analysis identified inter-α-trypsin inhibitor heavy chain 1 (ITIH1) as a protein secreted by liver that was responsible for systemic insulin resistance in Gna13- deficient mice. Liver expression of ITIH1 positively correlated with surrogate markers for diabetes in patients with impaired glucose tolerance or overt diabetes. Mechanistically, a decrease in hepatic Gα 13 caused ITIH1 oversecretion by liver through induction of O -GlcNAc transferase expression, facilitating ITIH1 deposition on the hyaluronan surrounding mouse adipose tissue and skeletal muscle. Neutralization of secreted ITIH1 ameliorated glucose intolerance in obese mice. Our findings demonstrate systemic insulin resistance in mice resulting from liver-secreted ITIH1 downstream of Gα 13 and its reversal by ITIH1 neutralization.
Type of Medium:
Online Resource
ISSN:
1946-6234
,
1946-6242
DOI:
10.1126/scitranslmed.aan4735
Language:
English
Publisher:
American Association for the Advancement of Science (AAAS)
Publication Date:
2019
