ALR inhibits HBV replication and autophagosome formation by ameliorating HBV-induced ROS production in hepatic cells.

Abstract

HBV has a small genome and thrives in the infected hepatocytes by hijacking the cellular machinery and cellular pathways. HBV induces incomplete autophagy for its replication and survival. This study showed that HBV replication induces Reactive oxygen species (ROS) production, which in turn augments the formation of autophagosomes. Augmenter of liver regeneration (ALR) is a sufhydryl oxidase and has an anti-oxidative property. We sought to determine the interplay between HBV and antioxidant protein ALR. We showed that HBV downregulated ALR expression in hepatic cells. There was increased ROS production in HBV-infected cells while ALR downregulated ROS levels and expression of NADPH oxidase NOX4. N-acetyl cysteine, a ROS scavenger, downregulated ROS level and autophagosome formation in HBV-expressing cells. ALR overexpression in HBV-expressing cells downregulated the expression of autophagy marker proteins while upregulated the expression of p-MTOR. ALR overexpression decreased the expression of HBx, HBsAg, and total HBV load. This study showed that HBx relieved ALR-mediated inhibition by upregulating the miR-181a expression in HBV-infected cells, which in turn downregulated ALR expression.