Characterization of In Vitro Engineered Human Adipose Tissues: Relevant Adipokine Secretion and Impact of TNF-α

PLoS One. 2015 Sep 14;10(9):e0137612. doi: 10.1371/journal.pone.0137612. eCollection 2015.

Abstract

Representative modelling of human adipose tissue functions is central to metabolic research. Tridimensional models able to recreate human adipogenesis in a physiological tissue-like context in vitro are still scarce. We describe the engineering of white adipose tissues reconstructed from their cultured adipose-derived stromal precursor cells. We hypothesize that these reconstructed tissues can recapitulate key functions of AT under basal and pro-inflammatory conditions. These tissues, featuring human adipocytes surrounded by stroma, were stable and metabolically active in long-term cultures (at least 11 weeks). Secretion of major adipokines and growth factors by the reconstructed tissues was determined and compared to media conditioned by human native fat explants. Interestingly, the secretory profiles of the reconstructed adipose tissues indicated an abundant production of leptin, PAI-1 and angiopoietin-1 proteins, while higher HGF levels were detected for the human fat explants. We next demonstrated the responsiveness of the tissues to the pro-inflammatory stimulus TNF-α, as reflected by modulation of MCP-1, NGF and HGF secretion, while VEGF and leptin protein expression did not vary. TNF-α exposure induced changes in gene expression for adipocyte metabolism-associated mRNAs such as SLC2A4, FASN and LIPE, as well as for genes implicated in NF-κB activation. Finally, this model was customized to feature adipocytes representative of progressive stages of differentiation, thereby allowing investigations using newly differentiated or more mature adipocytes. In conclusion, we produced tridimensional tissues engineered in vitro that are able to recapitulate key characteristics of subcutaneous white adipose tissue. These tissues are produced from human cells and their neo-synthesized matrix elements without exogenous or synthetic biomaterials. Therefore, they represent unique tools to investigate the effects of pharmacologically active products on human stromal cells, extracellular matrix and differentiated adipocytes, in addition to compounds modulating adipogenesis from precursor cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adipokines / metabolism*
  • Adipose Tissue / drug effects
  • Adipose Tissue / metabolism*
  • Chemokine CCL2 / metabolism
  • Enzyme-Linked Immunosorbent Assay
  • Fatty Acid Synthase, Type I / genetics
  • Fatty Acid Synthase, Type I / metabolism
  • Gene Expression Regulation
  • Glucose Transporter Type 4 / genetics
  • Glucose Transporter Type 4 / metabolism
  • Hepatocyte Growth Factor / metabolism
  • Humans
  • NF-kappa B / metabolism
  • Nerve Growth Factor / metabolism
  • RNA, Messenger / metabolism
  • Tissue Engineering*
  • Tumor Necrosis Factor-alpha / pharmacology*
  • Vascular Endothelial Growth Factor A / metabolism

Substances

  • Adipokines
  • CCL2 protein, human
  • Chemokine CCL2
  • Glucose Transporter Type 4
  • HGF protein, human
  • NF-kappa B
  • NGF protein, human
  • RNA, Messenger
  • SLC2A4 protein, human
  • Tumor Necrosis Factor-alpha
  • VEGFA protein, human
  • Vascular Endothelial Growth Factor A
  • Hepatocyte Growth Factor
  • Nerve Growth Factor
  • FASN protein, human
  • Fatty Acid Synthase, Type I

Grants and funding

This work was supported by the National Science and Engineering Research Council (NSERC, grant #326987) and in part by the Canadian Institutes of Health Research (CIHR, grant #111233, Figs 3 and 4) awarded to JF. We acknowledge the support of the Centre de recherche du CHU de Québec du Fonds de recherche du Québec-Santé (FRQ-S) and of the Réseau ThéCell du FRQ-S. The confocal imaging system was obtained through the Fonds des leaders program from Canada Foundation for Innovation (CFI) to JF. KA received a studentship from Fonds de recherche du Québec—Nature et technologies (FRQ-NT). MS received studentships from CIHR and Laval University Faculty of Medicine. MP received studentships from NSERC, FRQ-S and the Canadian Federation of University Women (CFUW). JF is a FRQ-S career award scholar. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.