Stretch-induced activation of CASA in cyclically stretched human TM cells. (A) Primary cultures of human TM cells at passage 3 were grown on collagen-I coated Flexcell plates to confluency and subjected to cyclic mechanical stretch (20% elongation, 1 cycle/second) for 24 hours in the presence of vehicle, the autophagy activator rapamycin (1uM), or the autophagy inhibitor 3-MA (10mM) added in fresh culture media prior application of mechanical forces. Lipidation of LC3-I to LC3-II were evaluated by WB. (B) Primary cultures of human TM cells were transfected with siRNA against human BAG3 (siBAG3), Atg5 (siAtg5), or control (siNC) and subjected to cyclic mechanical stretch (20% elongation, 1 cycle/second, 24 hours) at 48 hours post-transfection. Protein levels of BAG3, Atg5, and LC3-II were evaluated by WB. Three different cell lines were used for these experiments. (C) Normalized relative protein levels calculated from densitometric analysis of the blots. Data are the means ± SD, n = 3, *p<0.05, ***p < 0.0001. C: Control; S: Stretched.