Cited by 972Liver Disease Diagnosis and TreatmentDiabetes, Cardiovascular Risks, and LipoproteinsAdipokines, Inflammation, and Metabolic Diseases

The DOI matches its Crossref record; 55 of the 55 references it cites were found in a registry or an index; none of the 29 sources its claims cite is checked for support yet.

Intrahepatic fat, not visceral fat, is linked with metabolic complications of obesity

Open access

Abstract

Visceral adipose tissue (VAT) is an important risk factor for obesity-related metabolic disorders. Therefore, a reduction in VAT has become a key goal in obesity management. However, VAT is correlated with intrahepatic triglyceride (IHTG) content, so it is possible that IHTG, not VAT, is a better marker of metabolic disease. We determined the independent association of IHTG and VAT to metabolic function, by evaluating groups of obese subjects, who differed in IHTG content (high or normal) but matched on VAT volume or differed in VAT volume (high or low) but matched on IHTG content. Stable isotope tracer techniques and the euglycemic–hyperinsulinemic clamp procedure were used to assess insulin sensitivity and very-low-density lipoprotein–triglyceride (VLDL-TG) secretion rate. Tissue biopsies were obtained to evaluate cellular factors involved in ectopic triglyceride accumulation. Hepatic, adipose tissue and muscle insulin sensitivity were 41, 13, and 36% lower ( P < 0.01), whereas VLDL-triglyceride secretion rate was almost double ( P < 0.001), in subjects with higher than normal IHTG content, matched on VAT. No differences in insulin sensitivity or VLDL-TG secretion were observed between subjects with different VAT volumes, matched on IHTG content. Adipose tissue CD36 expression was lower ( P < 0.05), whereas skeletal muscle CD36 expression was higher ( P < 0.05), in subjects with higher than normal IHTG. These data demonstrate that IHTG, not VAT, is a better marker of the metabolic derangements associated with obesity. Furthermore, alterations in tissue fatty acid transport could be involved in the pathogenesis of ectopic triglyceride accumulation by redirecting plasma fatty acid uptake from adipose tissue toward other tissues.

Overview

AI snapshot

Written from the paper’s full text.

TL;DR

In obese nondiabetic adults, intrahepatic triglyceride (IHTG) content, rather than visceral adipose tissue (VAT) volume, was independently linked to multiorgan insulin resistance and increased hepatic VLDL-triglyceride secretion. The authors conclude that VAT’s association with metabolic disease may reflect its correlation with IHTG.

Key findings

  • When subjects were matched on VAT volume, those with high IHTG had 41%, 13%, and 36% lower hepatic, adipose tissue, and skeletal muscle insulin sensitivity, respectively (P < 0.01), and nearly double the VLDL-TG secretion rate (23 ± 2 vs. 12 ± 1 µmol/min; P < 0.001).
  • When subjects were matched on IHTG content, no differences in insulin sensitivity or VLDL-TG secretion were observed between low- and high-VAT groups.
  • In multivariate regression including age, sex, BMI, body fat percentage, IHTG, VAT, and subcutaneous abdominal adipose tissue, IHTG was the best predictor of insulin action in liver, skeletal muscle, and adipose tissue and of VLDL-TG secretion, accounting for 21%, 45%, 38%, and 21% of variability, respectively (P ≤ 0.01); VAT was not a predictor of any dependent variable.
  • Skeletal muscle CD36 gene expression was almost 3-fold greater with high IHTG (0.82 ± 0.16 vs. 0.34 ± 0.05 AU; P < 0.05), while adipose tissue CD36 gene expression was 35% lower and adipose CD36 protein was 43% lower in the high-IHTG group.

Methods

  • A total of 42 obese men and women were screened; 31 participated (mean BMI 35.7 ± 0.8 kg/m²), with 9 subjects assigned to more than one group. Subjects were nondiabetic and had no liver disease other than NAFLD.
  • Groups were matched either on VAT volume with normal vs. high IHTG, or on IHTG content with low vs. high VAT. Body composition was assessed by DXA, MRI, and proton magnetic resonance spectroscopy.
  • Metabolic function was assessed with stable isotope tracer techniques and a two-stage euglycemic-hyperinsulinemic clamp; VLDL-TG kinetics were measured with glycerol and palmitate tracers. Adipose and muscle biopsies were used for CD36 gene expression and protein analysis. Comparisons used t tests and stepwise linear regression.

Limitations

  • The paper states that the data cannot determine whether the IHTG–metabolic dysfunction association is cause-and-effect, and that insulin resistance could be a cause rather than a consequence of IHTG accumulation; other mechanisms for insulin resistance are also noted.
  • The authors state they did not measure CD36 gene expression or protein content in the liver, and instead infer likely hepatic CD36 changes from other studies.
  • Evident from the text: the sample was small (31 participants, generally 10 per group), and 9 subjects were assigned to more than one group to achieve matching, which may limit generalizability and independence of group comparisons.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1073/pnas.0904944106

Cites

55 of 55 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Verification

Claims the paper makes

37 Own result · 16 Not checked yet · 13 Own interpretation · 9 Own method

Verify all 29 references — free account

Show all 50 claims

  • It may state two separate claims as one. 10
  • Probably not a substantial claim. 9
  • The quote only partly states this claim. 7
25 of 25
  • The paper relies on this without support.

    A causal link between VAT and metabolic dysfunction has not been demonstrated in humans.

    “Although VAT is associated with metabolic disease, a causal link between VAT and metabolic dysfunction has not been demonstrated in humans.”
  • The paper relies on this without support.

    The mechanism(s) responsible for the interrelationship among IHTG content, insulin resistance, and hypertriglyceridemia is not known.

    “The mechanism(s) responsible for the interrelationship among IHTG content, insulin resistance, and hypertriglyceridemia is not known, but could involve redirecting plasma FFA uptake and intracellular triglyceride production from adipose tissue depots to other tissues, such as liver and skeletal muscle, which can impair insulin signaling (13,14) and stimulate VLDL-TG secretion (11).”
  • The paper relies on this without support.

    The mechanism responsible for excessive triglyceride accumulation in nonadipose tissues (i.e., ectopic fat) is not known.

    “The mechanism responsible for excessive triglyceride accumulation in nonadipose tissues (i.e., ectopic fat) is not known.”
  • The paper relies on this without support.

    The mechanism responsible for differences in tissue CD36 content is not known.

    “The mechanism responsible for differences in tissue CD36 content is not known, but could be related to circulating insulin, because plasma insulin concentration was inversely correlated with adipose tissue CD36 expression and directly correlated with muscle insoluble CD36 content in our subjects.”
  • The paper relies on this without support.

    It is not known whether IHTG or VAT is independently associated with metabolic risk.

    “However, it is not known whether IHTG or VAT is independently associated with metabolic risk because both are strongly correlated with each other (8-10).”
  • The authors state this as an assumption.

    Glucose rate of disappearance from plasma was equal to glucose rate of appearance during basal conditions.

    “It was assumed that glucose rate of disappearance (Rd) from plasma was equal to glucose rate of appearance (Ra) during basal conditions”
  • The authors state this as an assumption.

    During the clamp procedure, glucose rate of disappearance was equal to the sum of endogenous glucose rate of appearance and the rate of infused glucose.

    “during the clamp procedure glucose Rd was assumed to be equal to the sum of endogenous glucose Ra and the rate of infused glucose.”
7 of 7

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?

Citations

Cites

Show all 55 references

Cited by

Sorted by citations

Items 501–600 of 969

Metadata

Authors
Fabbrini, E., Magkos, F., Mohammed, B. S., Pietka, T., Abumrad, N. A., Patterson, B. W., Okunade, A., & Klein, S.
Affiliations
Washington University in St. Louis (US)
Corresponding author
Klein, Samuel
Venue
Proceedings of the National Academy of Sciences
Published
2009-09-08
Volume
106
Issue
36
Pages
15430-15435
ISSN
  • 0027-8424 (ISSN-L)
  • 1091-6490
OpenAlex
W2077963393
Cited by
972
References
55
Citations by year
2026: 17 · 2025: 27 · 2024: 34 · 2023: 47 · 2022: 50 · 2021: 45 · 2020: 54 · 2019: 55 · 2018: 56 · 2017: 56 · 2016: 60 · 2015: 76 · 2014: 87 · 2013: 89 · 2012: 77
FWCI
49.01
Type
journal article
Language
en
Open access
Locations
  • Proceedings of the National Academy of Sciences (publishedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
  • Digital Commons@Becker (Washington University School of Medicine) (submittedVersion)
Funders
  • National Institutes of Health (5r01dk060022-19, 5p41rr000954-34, UL1TR000448)
  • National Institute of Diabetes and Digestive and Kidney Diseases (R01DK033301, DK33301, DK37948, DK56341, R01DK037948, DK-60022, R01-DK-060022, P30DK056341)
  • National Center for Research Resources (P41-RR000954, RR 00954, UL1RR024992)
  • National Center for Advancing Translational Sciences
Topics
  • Health Sciences › Medicine › Hepatology › Liver Disease Diagnosis and Treatment
  • Health Sciences › Medicine › Endocrinology, Diabetes and Metabolism › Diabetes, Cardiovascular Risks, and Lipoproteins
  • Health Sciences › Medicine › Endocrinology, Diabetes and Metabolism › Adipokines, Inflammation, and Metabolic Diseases
Keywords
intrahepatic triglyceride, visceral adipose tissue, obesity, insulin sensitivity, VLDL triglyceride secretion, CD36, fatty acid uptake, hepatic insulin resistance, skeletal muscle insulin sensitivity, adipose tissue insulin sensitivity, metabolic complications of obesity
MeSH terms
Body Composition, Female, Glucose, Humans, Lipoproteins, VLDL, Liver, Male, Metabolic Diseases, Obesity, Palmitates, Triglycerides, Glucose Clamp Technique, DNA Primers, CD36 Antigens, Reverse Transcriptase Polymerase Chain Reaction, Intra-Abdominal Fat

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.

A language model drew the claims from the paper on 2026-10-09, under version 3 of the claim definition (model deepseek-v4.1-flash, prompt extract-v3).

A second model labelled each claim on 2026-10-09 (model jev-1.13-20260917, definition revision gold-guideline-v0.2).

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