Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2008 Jan 29;105(4):1297-302.
doi: 10.1073/pnas.0707849104. Epub 2008 Jan 23.

Hepatic NF-kappa B essential modulator deficiency prevents obesity-induced insulin resistance but synergizes with high-fat feeding in tumorigenesis

F Thomas Wunderlich  1 , Tom Luedde, Stephan Singer, Marc Schmidt-Supprian, Julia Baumgartl, Peter Schirmacher, Manolis Pasparakis, Jens C Brüning
Affiliations

Hepatic NF-kappa B essential modulator deficiency prevents obesity-induced insulin resistance but synergizes with high-fat feeding in tumorigenesis

F Thomas Wunderlich et al. Proc Natl Acad Sci U S A. .

Abstract

Development of obesity-associated insulin resistance and diabetes mellitus type 2 has been linked to activation of proinflammatory pathways in the liver, leading to impaired insulin signal transduction. To further define the role of hepatic NF-kappaB activation in this process, we have analyzed glucose metabolism in mice with liver-specific inactivation of the NF-kappaB essential modulator gene (NEMO(L-KO) mice) exposed to a high-fat diet (HFD). These animals are protected from the development of obesity-associated insulin resistance, highlighting the importance of hepatic NF-kappaB activation in this context. However, hepatic NEMO deficiency synergizes with HFD in the development of liver steatosis as a consequence of decreased peroxisome proliferator-activated receptor (PPAR-alpha) and increased PPAR-gamma expression. Steatosis interacts with increased inflammation, causing elevated apoptosis in the livers of these mice under HFD. These changes result in liver tumorigenesis of NEMO(L-KO) mice under normal diet, a process that is largely aggravated when these mice are exposed to HFD. These data directly demonstrate the interaction of hepatic inflammation, dietary composition, and metabolism in the development of liver tumorigenesis.

PubMed Disclaimer

Conflict of interest statement

The authors declare no conflict of interest.

Figures

Fig. 1.
Fig. 1.
Metabolic phenotype of NEMOL-KO mice on NCD and HFD. (a) Body weights of WT mice on a NCD (open circles) and a HFD (open squares) were compared with NEMOL-KO mice on NCD (filled circles) and HFD (filled squares). The weight of nine mice was determined weekly for each genotype. (b) The epigonadal fat pad weight of WT (white bars) and NEMOL-KO (black bars) on NCD and on HFD was measured at week 19 (n = 9 per genotype). (c) Body compositions of WT (white bars) and NEMOL-KO (black bars) on NCD and on HFD were determined by using a Brucker minespec (n = 7 per genotype). (d) Glucose tolerance tests of WT mice on NCD (open circles), on HFD (open squares) and of NEMOL-KO mice on NCD (filled circles) and on HFD (filled squares) were performed at week 12 (n = 9 per genotype). (e) Insulin tolerance tests of mice with the indicated genotypes were performed at week 13 (n = 9 per genotype). (f) Serum insulin levels were determined by ELISA from sera of mice with the indicated genotypes at 8 and 16 weeks of age (n = 9 per genotype). (g) Fasted blood glucose was evaluated at week 13 (n = 9 per genotype). (h) Relative expression of gluconeogenic enzymes PEPCK and G6P were determined by real-time PCR from liver samples of the indicated genotypes (n = 8 per genotype) using TaqMan Assay. (i) Representative insulin signaling of mice with the indicated genotypes by using Western blot analysis with the indicated antibodies. Mice were injected into the vena cava with 125 μl of 40 units/ml insulin upon anesthetization. Values are mean ± SEM. *, P ≤ 0.05; **, P ≤ 0.001 vs. control.
Fig. 2.
Fig. 2.
Macrovesicular steatosis in livers of NEMOL-KO mice. (a) Representative Sudan staining from liver sections of control and NEMOL-KO mice on NCD and HFD at 5 months of age. Sections were counterstained with hematoxylin. (b) Percentage of macrovesicular lipid accumulations in lipid containing hepatocytes. (c) Relative expression of the indicated genes from the different genotypes was performed by real-time PCR by using TaqMan Assay (n = 8 per genotype). Values are mean ± SEM. *, P ≤ 0.05; **, P ≤ 0.001 vs. control. (d) Triglyceride and (e) cholesterol levels from sera of control and NEMOL-KO mice on NCD and HFD at week 16 were determined by a diagnostic laboratory using standard techniques (n = 16 per genotype).
Fig. 3.
Fig. 3.
Massive macrophage infiltration into livers of NEMOL-KO mice leads to up-regulation of proinflammatory cytokines, induction of cell death and compensatory proliferation. (a) Immunohistochemistry of liver cryostat sections of control and NEMOL-KO mice using F4/80 antibody to detect infiltrating macrophages. (b) Relative expression of MCP-1 and TNF-α in livers of control and NEMOL-KO mice on NCD and HFD was determined by real-time PCR using TaqMan Assay (n = 8 per genotype). (c) Evaluation of IL-6 levels was performed by ELISA from sera of control and NEMOL-KO mice on NCD and HFD at 16 weeks of age. (d) Representative Western blots of liver protein lysates from control and NEMOL-KO mice on NCD and HFD using the indicated antibodies (n = 3 per genotype). (e) Quantitation of P-STAT-3 intensities from Western blots shown in d by using Quantity one software. (f) Determination of apoptosis by TUNEL staining of livers of control and NEMOL-KO mice was expressed as percentage of total cells. TUNEL-stained liver sections were counterstained with DAPI and from five exemplary sections (see SI Fig. 7) for each value DAPI as well as TUNEL-positive cells were counted (n = 5 per genotype). Values are mean ± SEM. *, P ≤ 0.05; **, P ≤ 0.001 vs. control.
Fig. 4.
Fig. 4.
HFD drastically elevates spontaneous tumorigenesis in livers of NEMOL-KO mice. (a) Exemplary demonstration of ex situ isolated livers of control and NEMOL-KO mice on NCD and HFD. (b) Macroscopic quantitation of large (>2-mm) and small (≤2-mm) foci of NEMOL-KO mice on NCD and HFD (n = 5 per genotype) at week 19. (c) Representative paraffin sections of control and tumorigenic liver tissue from NEMOL-KO mice on NCD and HFD. (d) Determination of proliferating cells in livers of control and NEMOL-KO mice either on NCD or HFD was performed by immunohistochemistry using Ki-67 antibody. (e) Microscopic quantitation of foci in livers of NEMOL-KO mice on a NCD and a HFD (n = 5 per genotype). A value of 1 expresses one to three foci/lobule, whereas a value of 2 represents more than three foci/lobule. Values are mean ± SEM. *, P ≤ 0.05; **, P ≤ 0.001 vs. control.
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Hotamisligil GS, Shargill NS, Spiegelman BM. Science. 1993;259:87–91. - PubMed
    1. Xu H, Barnes GT, Yang Q, Tan G, Yang D, Chou CJ, Sole J, Nichols A, Ross JS, Tartaglia LA, Chen H. J Clin Invest. 2003;112:1821–1830. - PMC - PubMed
    1. Plomgaard P, Bouzakri K, Krogh-Madsen R, Mittendorfer B, Zierath JR, Pedersen BK. Diabetes. 2005;54:2939–2945. - PubMed
    1. Hotamisligil GS, Arner P, Caro JF, Atkinson RL, Spiegelman BM. J Clin Invest. 1995;95:2409–2415. - PMC - PubMed
    1. Hotamisligil GS, Peraldi P, Budavari A, Ellis R, White MF, Spiegelman BM. Science. 1996;271:665–668. - PubMed

Publication types

MeSH terms

-