Hepatitis B virus (HBV) infection is a major risk factor for cirrhosis and liver cancer, and its treatment continues to be difficult. 

Previous studies demonstrated that a dopamine analog inhibited the packaging of pregenomic RNA into capsids. The present study. published in the Journal of Clinical and Translational Hepatology, aimed to determine the effect of dopamine on the expressions of hepatitis B virus surface and e antigens (HBsAg and HBeAg, respectively) and to elucidate the underlying mechanism.

Hepatitis_B_virus_01

Source: CDC/Dr. Erskine Palmer (PHIL #270), 1981

TEM micrograph of hepatitis B virions, also known as Dane particles.

The authors used dopamine-treated HBV-infected HepG2.2.15 and NTCP-G2 cells to monitor HBsAg and HBeAg expression levels. They analyzed interferon-stimulated gene 15 (ISG15) expression in dopamine-treated cells. Then they knocked down ISG15 and monitored HBsAg and HBeAg expression levels.

Methods used

The team analyzed the expression of Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathway factors in dopamine-treated cells. They used dopamine hydrochloride-treated adeno-associated virus/HBV-infected mouse model to evaluate HBV DNA, HBsAg, and HBeAg expression. HBV virus was collected from HepAD38.7 cell culture medium.

The authors found that dopamine inhibited HBsAg and HBeAg expression and upregulated ISG15 expression in HepG2.2.15 and HepG2-NTCP cell lines. ISG15 knockdown increased HBsAg and HBeAg expression in HepG2.2.15 cells. Dopamine-treated cells activated the JAK/STAT pathway, which upregulated ISG15 expression. In the adeno-associated virus-HBV murine infection model, dopamine downregulated HBsAg and HBeAg expression and activated the JAK-STAT/ISG15 axis.

They conclude that dopamine inhibits the expression of HBsAg and HBeAg by activating the JAK/STAT pathway and upregulating ISG15 expression.

Topics