Enhanced antiviral and antifibrotic effects of short hairpin RNAs targeting HBV and TGF-β in HBV-persistent mice

Abstract

The hepatitis B virus (HBV) causes acute and chronic liver infection, which may lead to liver cirrhosis and hepatocellular carcinoma. Current treatments including interferons and nucleotide analogs, have limited therapeutic effects, underscoring the need to identify effective therapeutic options to inhibit HBV replication and prevent complications. Previous animal models mimicking chronic HBV infection do not faithfully reflect disease progression in humans. Here, we used our established HBV-persistent mouse line with liver fibrosis to evaluate the efficacy of novel therapies. The combination of two short hairpin RNAs (dual-shRNA) against different coding regions of HBV delivered by a self-complementary AAV vector showed better antiviral effects than single shRNA both in vitro and in HBV-persistent mice. The dual-shRNA also exhibited stronger antifibrotic activity in vivo. Vector carrying shRNA against TGF-β, though did not inhibit HBV replication alone, enhanced the antiviral and antifibrotic activities of single and dual HBV shRNAs. Co-administration of TGF-β shRNA and HBV dual-shRNA decreased HBV DNA, HBV RNA, HBsAg, HBeAg, and liver fibrosis markers in serum and tissues, and improved liver morphology more effectively than single treatments. Our results suggest that the combination of shRNAs against HBV and TGF-β could be developed into a viable treatment for human HBV infection.

Short hairpin RNA attenuates liver fibrosis by regulating the peroxisome proliferator-activated receptor-γ and nuclear factor-κB pathways in hepatitis B virus-induced liver fibrosis in mice

“…These results suggested that AAVshRNA treatment inhibited lipogenesis and improved lipid metabolism. Hepatocyte steatosis was observed in HBV(+) mice, consistent with our previous study [77], and was alleviated after AAVshRNA treatment [44]. These findings suggested that AAVshRNA alleviated hepatocyte steatosis and liver fibrosis by decreasing hepatocyte fatty acid uptake and de novo lipogenesis via attenuation of FABP1 and ME1 expression.…”

“…Thus, it is necessary to elucidate the mechanisms of hepatic fibrosis and develop new medicines for blocking and reversing hepatic fibrosis. Our previous study showed that AAVshRNA had anti-hepatic fibrosis effects in HBV-replicated mice with liver fibrosis [44]. Moreover, fibrotic markers, including α-SMA, collagen I, and collagen III, were significantly reduced.…”

“…Removal of the causative agent (HBV) by RNA interference (RNAi) is an effective strategy for treating HBV-induced liver fibrosis, whereas inhibition of the TGF-β pathway alone is not effective. Our study showed the advantages of the combinatorial use of shRNAs against both HBV and TGF-β in alleviating liver fibrosis [44,45]. The mechanisms through which RNAi protects against HBV are unclear, and the inhibiting or activating responses of host factors remains elusive.…”

“…Our previous study demonstrated that co-administration of shRNAs targeting TGF-β and HBV decreased HBV antigens, HBV DNA, and liver fibrosis markers in the serum and livers of HBVreplicated mice [44]. In order to explore the mechanisms underlying the antiviral and antifibrotic effects, AAVdual-shRNA and AAVshRNA-TGF-β co-injection was evaluated.…”

“…However, no highly effective antifibrotic therapies are currently available. In our previous study, we found that adenoassociated virus (AAV) short hairpin RNAs (shRNAs) targeting HBV and TGF-β inhibited HBV replication and liver fibrosis in an HBV-induced liver fibrosis mouse model [44]. Removal of the causative agent (HBV) by RNA interference (RNAi) is an effective strategy for treating HBV-induced liver fibrosis, whereas inhibition of the TGF-β pathway alone is not effective.…”