Inhibitory Effect Of Ginkgo Biloba Extract (EGb761) On Hepatitis B Virus Secreting HBV Antigens In Vitro

Objective: To investigate the effect of Ginkgo biloba extracts (EGb761) on hepatitis B virus secreting the HBV antigens such as hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg)in vitro,and further research the value of traditional Chinese medicine in the course of hepatitis B virus.Methods: Part I: HepG2.2.15 cells were treated with different concentrations of EGb761. The toxicity of EGb761 on HepG2.2.15 cell was determined by MTT and the effect of EGb761 on inhibiting HepG2.2.15 cell secreting HBsAg and HBeAg was detected by time-resolved fluoroimmunoassay. Part II: HL-7702 cells and primary Tupaia hepatocytes were treated with different concentrations of EGb761 and human hepatitis B virus positive serum. Collected cell supernatant and DNA on 4d and 6d. HBsAg and HBeAg was detected by time-resolved fluoroimmunoassay. HBV DNA was detected by PCR.Results: Part I: After treating with different concentrations of EGb761,The result of MTT showed the absorbance A (OD) was not statistically significant by statistical analysis ( P> 0.05) in the two time periods (4d and 6d). The absorbance A of HBsAg and HBeAg in the culture supernatant of the cells treated with EGb761 were obviously lower than that of the untreated cells (P < 0.05). The level of HBsAg in the supernatant on 4d was less than that on 6d after treated with concentrations of EGb761 from 55μg/ml to 1750μg/ml,meanwhile inhibition ratio of HBsAg on 4d is greater than that on 6d. The absorbance A of HBeAg in the culture supernatant of the cells on 4d is more than that on 6d after treated with concentrations of EGb761 from 14μg/ml to 1750μg/ml,otherwise inhibition ratio of HBeAg on 4d is greater than that on 6d. Part II: HL-7702 cells and primary Tupaia hepatocytes were treated with human hepatitis B virus after different concentrations of EGb761 intervention,the HBsAg in supernatant is positive and the absorbance A (OD) was not statistically significant by statistical analysis(P>0.05). The results of PCR showed HBV DNA within the cells did not have definite trends.Conclusion: 1. EGb761 had no obvious toxicity to HepG2.2.15 cells in concentrations from 14μg/ml to 1750μg/ml. 2.The concentrations of EGb761 from 27μg/ml to 1750μg/ml have obvious inhibitory to HepG2.2.15 cell secreted HBsAg and the effect of inhibition was decrease accompanied with the dose lower and lower, otherwise the concentrations of EGb761 from 219μg/ml to 1750μg/ml have obvious inhibitory to HepG2.2.15 cell secreted HBeAg and the effect of inhibition was decrease accompanied with the dose lower and lower. 3. EGb761 at lower dose could inhibit HepG2.2.15 cell secreted HBsAg,however at high dose it could inhibit HepG2.2.15 cell secreted HBeAg. In addition there exist the tread,the inhibition on HBsAg is greater on HBeAg. 4. After treated with different concentrations of EGb761,there have the tread that the inhibition ratio of HBV antigens on 4d is greater than on 6d. 5. 27μg/ml of EGb761 is the lest dose to inhibit HepG2.2.15 cell secreting HBsAg to the culture supernatant and 219μg/ml of EGb761 is the lest dose to inhibit HepG2.2.15 cell secreting HBeAg to the culture supernatant. 6. HL-7702 cells can be infected by hepatitis B virus,but cannot use it as a HBV cell model at natural infect state. 7. Primary Tupaia hepatocytes can be infected by hepatitis B virus.