Porcine circovirus type 2 induces CHOP-ERO1α-ROS-mediated apoptosis in PK-15 cells

Porcine circovirus type 2 (PCV2) Infection induces endoplasmic reticulum (ER) stress and oxidative stress. These cellular responses could be connected with Apoptosis. However, the mechanisms that link ER stress and oxidative stress in PCV2-induced Apoptosis are poorly characterized. Here, we demonstrate that PCV2 Infection increased expression of proapoptotic protein C/EBP homologous protein (CHOP) and ER oxidoreductase 1 alpha (ERO1α). Inhibition of CHOP by RNA silencing or inhibition of ERO1α by short hairpin RNA or EN460 repressed PCV2-induced Reactive Oxygen Species (ROS) generation, cytosolic calcium level, and apoptotic rate in PK-15 cells. Overexpression of ERO1α enhanced PCV2-induced oxidative stress, Caspase-3 cleavage, and Apoptosis rate. Treatment of PCV2-infected cells with ROS scavenger N-acetyl-L-cysteine downregulated PCV2-induced ROS production, cytosolic calcium level, and Apoptosis rate, but intriguingly decreased expression of CHOP and ERO1α. Thus, we propose that PCV2 induces Apoptosis through ER Stress via CHOP-ERO1α-ROS signaling in host cells.