Figure 6.

Oil red O staining for day 21 for (a). Control (0 g) and vibrated groups ((b) 0.3 g, (c) 3 g, and (d) 6 g). Blue arrows indicate Oil red O-positive red-colored lipid droplets. Due to the 3D nature of the microspheres, the lipid droplets appear as spherical stains distinct and separate from cells (inset). There were only a total of seven microspheres (an average of 2.3 ± 0.7) with positive Oil red O stain counted in all the samples, with all seven from the control non-vibrated group. These droplets did not appear until day 21. Images were adjusted for brightness and contrast. Scale bars are 100 µm.