[Effect and mechanism of danshensu on hepatitis B virus reverse transcriptase and antigen expression].

MTT assay was used in this study to investigate the inhibitory effect of danshensu on the activity of 2.2.15 cells among human hepatoma cell line (HepG2); indirect fluorescence labeling method was used to measure the changes of reactive oxygen levels in the cells; ELISA method was used to determine hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) levels in cellular supernatants; HBV DNA level was measured with fluorogenic quantitative PCR method. The inhibitory effect of danshensu on HBV RT(hepatitis B virus reverse transcriptase) was studied by using enzyme inhibition dynamics, and the effect of danshensu on secondary structure of HBV reverse transcriptase was monitored by using circular dichroism. The results showed that danshensu had a good inhibitory effect on the growth of HepG2.2.15 cells, with a half inhibitory concentration (IC50) of (15.35±2.43) µmol•L⁻¹; danshensu could significantly inhibit HBsAg and HBeAg expressions, and showed an inhibitory effect on HBV DNA replication. In addition, danshensu was an effective inhibitor for HBV reverse transcriptase [IC50 (21.32±2.43) µmol•L⁻¹]. The fluorescence labeling results showed that the reactive oxygen levels in the cells were increased with the increase of danshensu concentration. Circular dichroism analysis showed that danshensu could induce partial change of conformation of HBV reverse transcriptase and gradually increased α-helical content. These results indicated that danshensu could make the structure of the enzyme become closer by binding to HBV reverse transcriptase, which was not conducive to the formation of the active center, so it could finally decrease the activity of HBV reverse transcriptase. Such decrease in enzyme activity would directly affect the HBV DNA replication, and combined with the decrease of the antigen levels, the effect of danshensu on HBV was increased.

[Effects of oxymatrine on serum cytokines and hepatic fibrotic indexes in patients with chronic hepatitis B].

OBJECTIVE: To study the effect of oxymatrine on serum cytokines and hepatic fibrotic indexes in patients with chronic hepatitis B (CHB). METHODS: Eighty-two CHB patients were randomly assigned to the control group treated with Western routine therapy and the treated group treated by Western routine therapy plus oxymatrine. The treatment course was 24 weeks. Another group with 20 healthy subjects was set as the normal control group. The serum levels of transforming growth factor-beta1 (TGF-beta1), interleukin-6 (IL-6), hyaline acid (HA), collagen type IV (C-IV) and laminin (LN) were measured by ELISA and RIA before and after treatment. RESULTS: The serum levels of TGF-beta1, IL-6, HA, C-IV and LN in CHB patients were significantly higher than those in the normal control group (P < 0.01). After 24-week treatment with oxymatrine, these abnormal indexes in the treated group were significantly lowered, as compared with those before treatment and in the control group, the differences were significant (all P < 0.01). CONCLUSION: Oxymatrine could lower the levels of cytokines, including TGF-beta1, IL-6, etc. in patients with CHB, which might be one of the mechanisms of its action in reversing liver fibrosis.