Figure 1.

Carbon nanotubes (CNT)-induced autophagy. Schematic representation of the proposed mechanism for HTT2800. During autophagy, a double-layered, membrane-bound autophagosome is formed that surrounds the proteins and damaged organelles identified for degradation. When autophagy is blocked by 3-MA, caspase-3 activation is induced. Autophagy inhibition accelerates apoptosis in cells. Furthermore, HTT2800-induced autophagic cell death occurred in the absence of caspase activation, via an ROS-independent pathway. These results suggest that HTT2800 predominantly causes autophagy rather than apoptotic cell death in BEAS-2B cells.