Hepatitis B Virus Disrupts Mitochondrial Dynamics: Induces Fission and Mitophagy to Attenuate Apoptosis
Figure 5
Attenuation of mitochondrial apoptosis by HBV.
(A–C) Parkin silencing accelerates HBV-induced mitochondrial apoptotic signaling. HepG2 and HepAD38 cells grown in the absence or presence of tetracycline were transfected with non-targeting (NT) and Parkin siRNA, respectively, for 72 h. Cells were used for Western blot analysis using antibodies specific to the indicated proteins (A), caspase-3/7 activity assay (B), and TUNEL assay (C). (D) A model elucidating HBV-induced aberrant mitochondrial dynamics in mitochondrial apoptosis. HBV induces immoderate stimulation in mitochondrial fission and mitophagy through mitochondrial translocation of Drp1 and Parkin, respectively, eventually causing disruption in mitochondrial dynamics. Inhibition of mitophagy by Parkin silencing can lead to apoptotic cell death in HBV-infected host cells via accumulation of apoptotic signal (red).