title: [Inhibition of HIV-1 mediated cell-cell fusion by saponin fraction from Psidium guajava leaf].
abstract: OBJECTIVE
  To investigate the effects of the total saponin of Psidium guajava leaf (TSGL) on HIV-1 envelop proteins (env) mediated virus entry into target cells.
  
  
  METHODS
  The TSGL was purified and concentrated using SA-1 macropore resin. The effect of TSGL on HIV-1 entry into target cells was tested using a cell-cell fusion assay by mixing CHO-WT and MT-2 cells. The cytotoxicity of TSGL was measured by MTT assay. The activity of TSGL on blocking the HIV-1 gp41 six helical bundle (6-HB) formation was analyzed by ELISA and Native-PAGE (N-PAGE).
  
  
  RESULTS
  The TSGL could inhibit HIV env mediated cell-cell fusion with an IC50 of (7.33 +/- 0.40) microg/mL, and displayed little cytotoxicity at that concentration. ELISA assay showed that the TSGL could prevent gp41 6-HB formation with inhibitory activity of 95.93% at 25 microg/mL. N-PAGE study confirmed the inhibitory effect of TSGL on gp41 6-HB formation.
  
  
  CONCLUSIONS
  The TSGL can inhibit HIV entry target cells by interfering the envelop subunit gp41 form the critical 6-HB structure.
authors: School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China. emao-2005@163.com
authors: Qin-Chao
authors: QC
authors: Mao
authors: Ying-Chun
authors: YC
authors: Zhou
authors: Run-Ming
authors: RM
authors: Li
authors: Yi-Ping
authors: YP
authors: Hu
authors: Shu-Wen
authors: SW
authors: Liu
authors: Xiao-Juan
authors: XJ
authors: Li
mesh_terms: D002459:Cell Fusion; D002460:Cell Line; D004305:Dose-Response Relationship, Drug; D004797:Enzyme-Linked Immunosorbent Assay; D015700:HIV Envelope Protein gp41 / Q000737:chemistry / Q000187:drug effects* / Q000378:metabolism; D023581:HIV Fusion Inhibitors / Q000008:administration & dosage / Q000494:pharmacology*; D015497:HIV-1 / Q000187:drug effects* / Q000502:physiology; D006801:Humans; D008826:Microbial Sensitivity Tests; D018515:Plant Leaves / Q000737:chemistry; D031647:Psidium / Q000737:chemistry*; D012503:Saponins / Q000008:administration & dosage / Q000494:pharmacology*; D053586:Virus Internalization / Q000187:drug effects
chemical_list: D015700:HIV Envelope Protein gp41; D023581:HIV Fusion Inhibitors; D012503:Saponins