ApoE and the role of very low density lipoproteins in adipose tissue inflammation

Atherosclerosis. 2012 Aug;223(2):342-9. doi: 10.1016/j.atherosclerosis.2012.06.003. Epub 2012 Jun 19.


Objective: To identify the role of triglyceride-rich lipoproteins (TGRLs) and apoE, a major apolipoprotein in TGRLs, in adipose tissue inflammation with high-fat diet (HFD)-induced obesity.

Methods: Male apoE(-/-) and C57BL/6J wild-type (WT) mice fed HFD for 12 weeks were assessed for metabolic and inflammatory parameters. ApoE(-/-) and WT mice were orally gavaged with [(3)H]palmitic acid to examine the role of apoE in fat delivery to adipose tissue. VLDL from obese apoE(-/-) mice were intravenously injected into lean WT or apoE(-/-) mice to test potential contribution of TGRLs-derived fat delivery to inflammation in adipose tissue and the role of apoE.

Results: ApoE(-/-) mice gained less body weight, and had less fat mass and lower triglyceride levels in skeletal muscle than WT. ApoE(-/-) mice on HFD had better insulin sensitivity than WT even when comparing body weight-matched mice. Compared to WT mice, apoE(-/-) mice on HFD had lower levels of inflammatory cytokines/chemokines and CD11c in adipose tissue, and lower levels of inflammatory markers in skeletal muscle. At 6 h after oral gavage with [(3)H]palmitic acid, incorporation of [(3)H]palmitic acid into adipose tissue and skeletal muscle was lower in apoE(-/-) mice. After repeated daily injection for 3 days, VLDL from obese apoE(-/-) mice induced inflammation in adipose tissue of recipient WT but not apoE(-/-) mice.

Conclusion: In HFD-induced obesity, apoE plays an important role in inflammation in adipose tissue and skeletal muscle, likely by mediating TGRL-derived fat delivery to these tissues.

Publication types

  • Research Support, N.I.H., Intramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adipose Tissue / immunology
  • Adipose Tissue / metabolism*
  • Adiposity
  • Animals
  • Apolipoproteins E / deficiency
  • Apolipoproteins E / genetics
  • Apolipoproteins E / metabolism*
  • Blood Glucose / metabolism
  • Cytokines / metabolism
  • Diet, High-Fat
  • Disease Models, Animal
  • Inflammation Mediators / metabolism
  • Injections, Intravenous
  • Insulin / blood
  • Lipoproteins, VLDL / administration & dosage
  • Lipoproteins, VLDL / metabolism*
  • Liver / metabolism
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Muscle, Skeletal / metabolism
  • Obesity / etiology
  • Obesity / genetics
  • Obesity / immunology
  • Obesity / metabolism*
  • Oxidative Stress
  • Palmitic Acid / administration & dosage
  • Palmitic Acid / metabolism
  • Panniculitis / etiology
  • Panniculitis / genetics
  • Panniculitis / immunology
  • Panniculitis / metabolism*
  • Panniculitis / prevention & control
  • Time Factors
  • Triglycerides / administration & dosage
  • Triglycerides / metabolism*
  • Weight Gain


  • Apolipoproteins E
  • Blood Glucose
  • Cytokines
  • Inflammation Mediators
  • Insulin
  • Lipoproteins, VLDL
  • Triglycerides
  • very low density lipoprotein triglyceride
  • Palmitic Acid