A short half-life of cccDNA offer or ignite hope for hepatitis B cure under nucleos(t)ide analogues treatment / 中华肝脏病杂志

Covalently closed circular DNA (cccDNA) of hepatitis B virus (HBV) is the template for HBV replication. Currently, there is a lack of therapeutic drugs that directly target cccDNA. Therefore, blocking cccDNA supplements as fast as possible and reducing the existing cccDNA is the key to achieving a complete cure of chronic hepatitis B. Previous studies have suggested that cccDNA had a long half-life, but a recent study showed that it only took a few months to update cycle of cccDNA pool, and its number was much less than previously predicted. In the future, with the advent of new antiviral drugs that can completely inhibit HBV replication, it is expected that the cccDNA pool will be completely cleared due to its supplement complete blockade, so as to achieve virological cure of chronic hepatitis B.

Exploring the mechanism of liver enzyme abnormalities in patients with novel coronavirus-infected pneumonia / 中华肝脏病杂志

To explore and analyze the possible mechanism of liver injury in patients with coronavirus disease 2019 (novel coronavirus pneumonia, NCP). The correlation between ALT, AST and other liver enzyme changes condition and NCP patients' disease status reported in the literature was comprehensively analyzed. ACE2 expression in liver tissue for novel coronavirus was analyzed based on single cell sequencing (GSE115469) data. RNA-Seq method was used to analyze Ace2 expression and transcription factors related to its expression in liver tissues at various time-points after hepatectomy in mouse model of acute liver injury with partial hepatectomy. -test or Spearman rank correlation analysis was used for statistical analysis. ALT and AST were abnormally elevated in some patients with novel coronavirus infection, and the rate and extent of ALT and AST elevation in severe NCP patients were higher than those in non-severe patients. Liver tissue results of single cell sequencing and immunohistochemistry showed that ACE2 was only expressed in bile duct epithelial cells of normal liver tissues, and very low in hepatocytes. In a mouse model of acute liver injury with partial hepatectomy, Ace2 expression was down-regulated on the first day, but it was elevated up to twice of the normal level on the third day, and returned to normal level on seventh day when the liver recovered and hepatocyte proliferation stopped. Whether this phenomenon suggests that the bile duct epithelial cells with positive expression of Ace2 participate in the process of liver regeneration after partial hepatectomy deserves further study. In RNA-Seq data, 77 transcription factors were positively correlated with the expression of ACE2 (r > 0.2, FDR < 0.05), which were mainly enriched in the development, differentiation, morphogenesis and cell proliferation of glandular epithelial cells. We assumed that in addition to the over activated inflammatory response in patients with NCP, the up-regulation of ACE2 expression in liver tissue caused by compensatory proliferation of hepatocytes derived from bile duct epithelial cells may also be the possible mechanism of liver tissue injury caused by 2019 novel coronavirus infection.