Abstract 538: Effects of Mechanical and Biological Factors on Responses of Vascular Smooth Muscle Cells
Biomechanical factors, including stretch, play a very important role in normal vascular function and in the early development of vascular diseases such as atherosclerosis. Although the cause(s) for vascular diseases have yet to be determined, we believe that effects of combined biological and biomechanical factors on smooth muscle cell (SMC) responses may play an important role in the maintenance of normal vascular functions and the disease development. Thus the main objective of this research is to investigate the responses of HASMCs (Human aortic smooth muscle cells) towards stretch and growth factors using the novel microarray stretch system developed in our group. HASMCs seeded on plasma-treated, fibronectin-coated PDMS microwells were exposed to either with or without various growth factors (i.e. EGF, FGF, VEGF, and TGFbeta) while stretching for a period of 72 hours. These cells were then observed under the microscope to evaluate the alignment and were analyzed for cell responses, including cell growth using the PicoGreen DNA assays. Static cells exposed with growth factors were also studied for comparison. We observed that HASMCs responded extensively to stretch as the cells aligned in the direction perpendicular to the direction of stretch, unlike the static conditions that showed random alignment. The addition of growth factors (10ng/ml) didn’t alter this cell alignment. Physiological level of stretch (10% strain) inhibited the cell proliferation induced by all of the studied growth factors with the highest inhibition observed in cells exposed to stretch and FGF. Our results indicate that we can apply our novel microarray stretch system to evaluate cell responses to stretch and various biological factors and that stretch and growth factors did alter cell behaviors. These results will also help us to better understand SMC responses to physical and biological changes and the involved mechanisms.
- © 2013 by American Heart Association, Inc.