Endothelial cells from visceral adipose tissue disrupt adipocyte functions in a three-dimensional setting: partial rescue by angiopoietin-1

Diabetes. 2014 Feb;63(2):535-49. doi: 10.2337/db13-0537. Epub 2013 Oct 15.

Abstract

During obesity, chronic inflammation of human white adipose tissue (WAT) is associated with metabolic and vascular alterations. Endothelial cells from visceral WAT (VAT-ECs) exhibit a proinflammatory and senescent phenotype and could alter adipocyte functions. We aimed to determine the contribution of VAT-ECs to adipocyte dysfunction related to inflammation and to rescue these alterations by anti-inflammatory strategies. We developed an original three-dimensional setting allowing maintenance of unilocular adipocyte functions. Coculture experiments demonstrated that VAT-ECs provoked a decrease in the lipolytic activity, adipokine secretion, and insulin sensitivity of adipocytes from obese subjects, as well as an increased production of several inflammatory molecules. Interleukin (IL)-6 and IL-1β were identified as potential actors in these adipocyte alterations. The inflammatory burst was not observed in cocultured cells from lean subjects. Interestingly, pericytes, in functional interactions with ECs, exhibited a proinflammatory phenotype with diminished angiopoietin-1 (Ang-1) secretion in WAT from obese subjects. Using the anti-inflammatory Ang-1, we corrected some deleterious effects of WAT-ECs on adipocytes, improving lipolytic activity and insulin sensitivity and reducing the secretion of proinflammatory molecules. In conclusion, we identified a negative impact of VAT-ECs on adipocyte functions during human obesity. Therapeutic options targeting EC inflammation could prevent adipocyte alterations that contribute to obesity comorbidities.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adipocytes / physiology*
  • Adipose Tissue / cytology*
  • Angiopoietin-1 / pharmacology*
  • Animals
  • Cell Culture Techniques
  • Endothelial Cells / physiology*
  • Humans
  • Inflammation
  • Insulin
  • Lipolysis / physiology
  • Obesity / metabolism
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism

Substances

  • Angiopoietin-1
  • Insulin
  • RNA, Messenger