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Cyclic strain affects the orientation of endothelial tubulogenesis in a frequency‐dependent manner
Author(s) -
Iwamoto Matthew Nobuo,
Joung InSuk,
Jensen Jake,
Chernyshev Vasiliy,
Shiu YanTing
Publication year - 2006
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.20.4.a716-a
Subject(s) - angiogenesis , strain (injury) , biophysics , mechanotransduction , chemistry , fibroblast , in vitro , biomedical engineering , anatomy , microbiology and biotechnology , materials science , biology , medicine , biochemistry
Angiogenesis occurs in a dynamic mechanical environment due to blood flow, but the role of hemodynamic forces in angiogenesis remains poorly understood. We recently developed a unique three‐dimensional in vitro system for studying the tubulogenesis of vascular endothelial cells (EC) under well‐defined cyclic strain (which mimics blood pressure‐induced stretch). The objective of this study was to investigate how the frequency of cyclic strain affects EC tubulogenesis. Briefly, ECs were cultured to confluence on the top of a collagen gel. The EC monolayer was then stimulated for 1 day with basic fibroblast growth factor to induce tubulogenesis. Next, these cells were kept as controls or stretched at a 10% elongational strain for two days at two different frequencies: 1/12 or 1 Hz. Cord‐like EC structures in the gel were monitored and analyzed with video microscopy and a commercial imaging software. We found that cyclic strain did not affect the number, depth, or length of the EC cords. However, cyclic strain induced the alignment of EC cords perpendicular to the principal axis of stretch; such an inductive effect was greater at a higher frequency. This in vitro system, along with the novel findings of strain‐modulated endothelial tube morphology, enables the formation of an experimental basis for understanding the role of cyclic strain in the regulation of angiogenesis. (A part of this data has been accepted for publication in Microvascular Research. This project is supported by a research grant from the Whitaker Foundation to YTS.)