Relationship between adipocyte size and adipokine expression and secretion

J Clin Endocrinol Metab. 2007 Mar;92(3):1023-33. doi: 10.1210/jc.2006-1055. Epub 2006 Dec 12.


Context: Adipocytes are known to release a variety of factors that may contribute to the proinflammatory state characteristic for obesity. This secretory function is considered to provide the basis for obesity-related complications such as type 2 diabetes and atherosclerosis.

Objective: To get a better insight into possible underlying mechanisms, we investigated the effect of adipocyte size on adipokine production and secretion.

Design, patients, and main outcome measures: Protein secretion and mRNA expression in cultured adipocytes separated according to cell size from 30 individuals undergoing elective plastic surgery were investigated.

Results: The mean adipocyte volume of the four fractions ranged from 205 +/- 146 to 1.077 +/- 471 pl. There were strong linear correlations for the secretion of adipokines over time. Secretion of leptin, IL-6, IL-8, TNF-alpha, monocyte chemoattractant protein-1, interferon-gamma-inducible protein 10, macrophage inflammatory protein-1beta, granulocyte colony stimulating factor, IL-1ra, and adiponectin was positively correlated with cell size. After correction for cell surface, there was still a significant difference between fraction IV (very large) and fraction I (small cells), for leptin, IL-6, IL-8, monocyte chemoattractant protein-1, and granulocyte colony-stimulating factor. In contrast, antiinflammatory factors such as IL-1ra and adiponectin lost their association after correction for cell surface area comparing fraction I and IV. In addition, there was a decrease of IL-10 secretion with increasing cell size.

Conclusions: The results clearly suggest that adipocyte size is an important determinant of adipokine secretion. There seems to be a differential expression of pro- and antiinflammatory factors with increasing adipocyte size resulting in a shift toward dominance of proinflammatory adipokines largely as a result of a dysregulation of hypertrophic, very large cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adipocytes / cytology*
  • Adipocytes / metabolism
  • Adiponectin / genetics*
  • Adiponectin / metabolism*
  • Adult
  • Cell Separation
  • Cell Size
  • Cells, Cultured
  • Female
  • Humans
  • Interleukins / blood
  • Interleukins / genetics*
  • Interleukins / metabolism*
  • Leptin / genetics*
  • Leptin / metabolism*
  • Male
  • Middle Aged
  • RNA, Messenger / analysis
  • Time Factors


  • Adiponectin
  • Interleukins
  • Leptin
  • RNA, Messenger