Polygalacin D inhibits the growth of hepatocellular carcinoma cells through BNIP3L-mediated mitophagy and endogenous apoptosis pathways / 中国天然药物

Platycodon grandiflorum (Jacq.) A. DC. is a famous medicinal plant commonly used in East Asia. Triterpene saponins isolated from P. grandiflorum are the main biologically active compounds, among which polygalacin D (PGD) has been reported to be an anti-tumor agent. However, its anti-tumor mechanism against hepatocellular carcinoma is unknown. This study aimed to explore the inhibitory effect of PGD in hepatocellular carcinoma cells and related mechanisms of action. We found that PGD exerted significant inhibitory effect on hepatocellular carcinoma cells through apoptosis and autophagy. Analysis of the expression of apoptosis-related proteins and autophagy-related proteins revealed that this phenomenon was attributed to the mitochondrial apoptosis and mitophagy pathways. Subsequently, using specific inhibitors, we found that apoptosis and autophagy had mutually reinforcing effects. In addition, further analysis of autophagy showed that PGD induced mitophagy by increasing BCL2 interacting protein 3 like (BNIP3L) levels.In vivo experiments demonstrated that PGD significantly inhibited tumor growth and increased the levels of apoptosis and autophagy in tumors. Overall, our findings showed that PGD induced cell death of hepatocellular carcinoma cells primarily through mitochondrial apoptosis and mitophagy pathways. Therefore, PGD can be used as an apoptosis and autophagy agonist in the research and development of antitumor agents.

Prediction of the Th/B cell epitopes on HA of influenza virus(H1N1)and antigenicity analysis / 中国免疫学杂志

Objective:To predict Th/B cell epitopes in HA of influenza virus(H1N1)and analyze antigenicity of the candidate epitopes in order to develop epitope-bacterin by the way of bioinformatics.Methods:The HA amino acid sequences of infiuenza virus(H1N1),which the viral infection was prevalent recently,were downloaded from Genbank.The Th/B cell epitopes were predicted and analyzed by bioinformatics methods.Then,specificity and conservation of the candidate epitopes were estimated.Finally,antigenicity of the candidate epitopes was identified by influenza virus(H1N1)positiVe serum samples of mice.Results:Three Th/B cell epitopes containing HA_(73-87),HA_(125-139),HA_(188-205) were acquired Two of the candidate epitopes were in a relatively conserved domain of HA1,and a deal of 2006-2009 influenza virus(H1N1)isolates contained the sequences.Moreover,the candidate epitopes were showedin a distinct antibody combining reactivity with the influenza virus (H1N1)positive serum of mice,which inferred the predicted epitopes to be functional ones.Conclusion:The selected epitopes are able to be functional HA Th/B cell epitopes of influenza virus(H1N1).Our study also establish the foundations for the further research of influenza virus infectlon and immunity mechanism,the recognition of influenza virus(H1N1)functional epitope and the development of epitope vaccines.

Prediction of the Th/B cell epitopes on HA of influenza virus(H1N1) and antigenicity analysis / 中国免疫学杂志

Objective:To predict Th/B cell epitopes in HA of influenza virus(H1N1) and analyze antigenicity of the candidate epitopes in order to develop epitope-bacterin by the way of bioinformatics.Methods:The HA amino acid sequences of influenza virus (H1N1),which the viral infection was prevalent recently,were downloaded from Genbank.The Th/B cell epitopes were predicted and analyzed by bioinformatics methods.Then,specificity and conservation of the candidate epitopes were estimated.Finally,antigenicity of the candidate epitopes was identified by influenza virus (H1N1) positive serum samples of mice.Results:Three Th/B cell epitopes containing HA73-87,HA125-139,HA188-205 were acquired.Two of the candidate epitopes were in a relatively conserved domain of HA1,and a deal of 2006-2009 influenza virus (H1N1) isolates contained the sequences.Moreover,the candidate epitopes were showedin a distinct antibody combining reactivity with the influenza virus (H1N1) positive serum of mice,which inferred the predicted epitopes to be functional ones.Conclusion:The selected epitopes are able to be functional HA Th/B cell epitopes of influenza virus (H1N1).Our study also establish the foundations for the further research of influenza virus infection and immunity mechanism,the recognition of influenza virus (H1N1) functional epitope and the development of epitope vaccines.