Study On Mechnism Of Anti-HBV Dehydrocostus Lactone Derivatives And Cytotoxic Essential Oils

Viral hepatitis induced by the Hepatitis B virus(HBV)is a virus-induced infectious disease that poses a serious threat to human life and health.Anti-HBV infection and treatment of hepatitis B viral hepatitis are still pending challenges in the life science and medical field.Around 296 million people around the world currently have chronic HBV infection,which accounts for nearly 1 million complications-related deaths annually.Once infected with HBV,it can lead to the deterioration of hepatocellular carcinoma(HCC).HCC has a high mortality rate and low survival rate,and is the second leading cause of cancer death worldwide.The current clinical drugs used for anti-HBV treatment are limited to interferon and nucleoside(acid)analogues,which have side effects,drug resistance,low conversion rate,and cannot be completely cured.Once HBV deteriorates into liver cancer,there are no effective drugs for treatment except for conventional treatments such as surgery and chemotherapy.Natural products are effective tool molecules for researching viral and cancer therapeutic drug targets and their mechanisms of action,which greatly advance the discovery of new targets and new mechanisms of action.Therefore,this thesis aims to discover natural products with anti-HBV and anti-cancer activities through phenotypic screening,and use them as tool molecules to study their therapeutic targets and mechanisms of action for hepatitis B and liver cancer,providing reference for the treatment of viral hepatitis B and liver cancer,as well as providing new targets for the discovery of drugs for the treatment of viral hepatitis B and liver cancer.The first chapter of this thesis focuses on an overview of the progress of research on the anti-HBV mechanism of action and targets of natural small molecules and the anti-liver cancer mechanism of action of essential oils,to understand the latest trends in the fields related to this thesis research and provide ideas for research directions and strategies.The second chapter of this paper conducted a phenotypic screen of 100 Dehydrocostus Lactone(DHC)and their derivatives for anti-HBV activity used HepG2.2.15 cells,and studied the target proteins and their mechanisms of the most significant compound DHC and its derivative DHC-D1.Based on transcriptome analysis and Connectivity map(CMap)analysis,the results suggested that DHC could inhibit HBV pg-RNA and preS1 RNA expression to exert its anti-HBV activity.Integrating differential gene expression profile analysis with CMap analysis suggested that DHC mediated immune response to exert its anti-HBV activity,and speculated that DHC might be a human tissue proteinase inhibitor,with CTSL,EHNT2 and SUV39H1 as its target proteins.In addition,DHC-D1 could significantly reduce HBV DNA copy number but not affect HBV RNA expression;integrating differential gene expression profile analysis with CMap analysis suggested that DHC-D1 might target HSPA1A and KRT23,meanwhile acting as a DNA inhibitor to affect HBV DNA synthesis.Chapter 3 of this thesis carried out the study of the anti-cancer activity and mechanism of action of plant essential oils.Firstly,the activity of more than 300 plant essential oils to inhibit the growth of hepatocellular carcinoma cells was carried out using human hepatocellular carcinoma cell line HepG2 cells,and it was found that cinnamon essential oil and Lemon myrtle essential oil(LMEO),had significant antihepatocellular carcinoma activity in vitro.The target proteins and their mechanism of action of LMEO with significant anti-hepatocellular carcinoma activity were further investigated by molecular network pharmacology and other techniques,and the results showed that LMEO showed cytotoxicity against different cancer cell lines in vitro(HepG2:IC50 40.90±2.23,SH-SY5Y:58.60±6.76,HT-29:68.91±4.62,A549:57.57±7.61 μg/mL),with the most significant inhibitory effect on HepG2 cells.The pharmacological network and combined with experimental confirmation suggests that LMEO inhibits the migration of HepG2 cells,and affects the S-phase of the cell cycle and apoptosis through the regulation of the p53 protein and its mediated downstreamrelated proteins.In addition,the anti-cancer activity of cinnamon essential oil was systematically investigated,and it was found that all of them significantly inhibited the proliferation and migration of hepatocellular carcinoma cells and had a wide range of anti-cancer activity in vitro,among which the essential oil EO-1-2 showed the best activity in a variety of cancer cells.Also based on network pharmacology analysis their potential targets were CTSD,TRIM24,ADAM10,APEX1 and NR1I2.In this thesis,natural monomer molecules and complex components were investigated for their targets and their mechanisms of action mainly by the CMap(Connectivity map)analysis method and network pharmacology analysis method,respectively.Among the 100 natural monomers screened for anti-HBV activity,DHC and DHC-D1 were used as examples to explore their target proteins and mechanisms.It was shown that DHC may be a human histone protease inhibitor with target proteins CTSL and EHNT2,while DHC-D1 may affect the synthesis of HBV DNA as a DNA inhibitor.In addition,among 320 essential oils screened for anti-tumor activity,the target proteins and mechanisms of LMEO and cinnamon essential oil were explored as examples.It was shown that LMEO could exert anti-HCC activity by modulating p53 protein and mediating downstream related proteins,and the potential target was APEX1.For cinnamon essential oil,the potential targets were CTSD,TRIM24,ADAM10,APEX1 and NR1I2.The research has provided not only strategies and references for the study of target proteins and mechanisms of natural monomeric molecules and complex fractions,but also provided new targets against hepatitis B and hepatocellular carcinoma,meanwhile provided the molecular basis and theoretical foundation for the treatment of tumors by aromatherapy of essential oils.