Inflammatory stress and altered angiogenesis evoked by very high-fat diets in mouse liver

Endocrinol Diabetes Nutr (Engl Ed). 2019 Aug-Sep;66(7):434-442. doi: 10.1016/j.endinu.2018.12.009. Epub 2019 Mar 1.
[Article in English, Spanish]

Abstract

Background: Non-alcoholic fatty liver disease (NAFLD), a condition that leads to fibrosis, is caused by intake of very high-fat diets (HFDs). However, while the negative impact on the liver of these diets has been an issue of interest, systematic research on the effect of HFDs are lacking.

Objective: To characterize the overall impact of HFDs on both molecular and morphological signs of liver remodeling.

Methods: A study was conducted on male C57BL/6J mice to assess the effect of 4- and 8-week HFDs (60% kcal from fat) on (i) liver steatosis and fibrosis, and (ii) expression of factors involved in inflammation and angiogenesis.

Results: After an 8-week HFD, vascular endothelial growth factor type-2 receptor (VEGF-R2) and fatty acid translocase/trombospondin-1 receptor (CD36) were overexpressed in liver tissue of mice given HFDs. These changes suggest impaired liver angiogenesis and occurred together with (i) increased GPR78-BiP and EIF2α phosphorylation, suggesting endoplasmic reticulum stress, (ii) induction of Col1a1 gene expression, a marker of fibrosis, and (iii) increased CD31 immunolabeling, consistent with active angiogenesis and fibrosis.

Conclusion: Our data show that very HFDs promote a rapid inflammatory response, as well as deregulation of angiogenesis, both consistent with development of liver fibrosis.

Keywords: CD36; Endoplasmic reticulum stress; Estrés del retículo endoplásmico; FCVE; Fibrosis hepática; Liver fibrosis; Obesidad; Obesity; VEGF.

MeSH terms

  • Adiposity
  • Animals
  • Body Weight
  • Diet, High-Fat / adverse effects*
  • Disease Models, Animal
  • Endoplasmic Reticulum Chaperone BiP
  • Endoplasmic Reticulum Stress
  • Gene Expression Regulation
  • Hepatitis, Animal / etiology*
  • Hepatitis, Animal / metabolism
  • Hepatitis, Animal / physiopathology
  • Inflammation Mediators / metabolism
  • Insulin / blood
  • Leptin / blood
  • Lipase / metabolism
  • Lipid Metabolism
  • Lipids / blood
  • Liver Cirrhosis / etiology
  • Liver Cirrhosis / metabolism
  • Liver Cirrhosis / physiopathology
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Neovascularization, Pathologic / etiology*
  • Non-alcoholic Fatty Liver Disease / etiology
  • Non-alcoholic Fatty Liver Disease / metabolism
  • Non-alcoholic Fatty Liver Disease / physiopathology

Substances

  • Endoplasmic Reticulum Chaperone BiP
  • Hspa5 protein, mouse
  • Inflammation Mediators
  • Insulin
  • Leptin
  • Lipids
  • Lipase