Angiogenesis in an in vivo model of adipose tissue development.
Obesity is associated with an increased risk for cardiovascular disease and cancer. Angiogenesis is a critical component of these pathological processes, and expanding adipose tissue represents one of the few sites of active angiogenesis in the adult. Despite the potential importance of angiogenesis in obesity, little is known about underlying mechanisms. This problem is magnified by the absence of useful quantitative model systems. In this report, we examine the angiogenic process using the 3T3-F442A model of adipose tissue development. In this model, 3T3-F442A preadipocytes are implanted subcutaneously into athymic Balb/c nude mice. We show that these cells develop into highly vascularized fat pads over the next 14-21 days, and that these fat pads are morphologically similar to normal subcutaneous adipose tissue. Histological studies demonstrate that a new microvasculature is evident as early as 5 days after cell implantation, and real-time quantitative RT-PCR analyses show that the expression of endothelial cell markers and adipogenesis markers increase in parallel during fat pad development. Finally, these preliminary studies suggest that the neovasculature originates by sprouting from larger, host-derived blood vessels that run parallel to peripheral nerves and that endothelial progenitor cells play little, if any, role in this process.
Neels
Jaap G
JG
The Scripps Research Institute, Department of Cell Biology, Division of Vascular Biology, La Jolla, California 92037, USA.
Thinnes
Terri
T
Loskutoff
David J
DJ
D041721:3T3-L1 Cells; D017667:Adipocytes / Q000166:cytology / Q000637:transplantation; D000273:Adipose Tissue / Q000098:blood supply* / Q000166:cytology / Q000254:growth & development* / Q000378:metabolism; D000818:Animals; D018507:Gene Expression Regulation, Developmental; D051379:Mice; D008819:Mice, Nude; D023421:Models, Animal; D018919:Neovascularization, Physiologic / Q000235:genetics / Q000502:physiology*; D009765:Obesity / Q000473:pathology / Q000503:physiopathology; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D033581:Stem Cell Transplantation; D013234:Stem Cells / Q000166:cytology; D013997:Time Factors
D019408:Platelet Endothelial Cell Adhesion Molecule-1; D012333:RNA, Messenger