title: Allicin prevents H₂O₂-induced apoptosis of HUVECs by inhibiting an oxidative stress pathway.
abstract: BACKGROUND
  Allicin, a primary ingredient of garlic, has been proposed to possess cardioprotective properties, which are commonly mediated by improved endothelial function.
  
  
  METHODS
  To investigate the effect and mechanism of allicin on the apoptosis of human umbilical vein endothelial cells (HUVECs), we used Propidium iodide (PI) staining and Annexin V/ PI staining assays to establish a model of oxidative stress apoptosis induced by H2O2. MTT, RT-PCR and western-blot assays were used to detect the effects and mechanism of allicin on the model.
  
  
  RESULTS
  PI staining, Annexin V/ PI staining assays and morphological assessment suggest that the cell death induced by 0.5 mM H2O2 is primarily apoptotic. Conversely, allicin reverses the effect of H2O2 on cell death, suggesting a role in protecting HUVECs from apoptosis. We demonstrated that H2O2 activates PARP cleavage, reduces pro-Caspase-3 levels and activates Bax expression; however, allicin inhibits each of these apoptotic signaling indicators. Allicin also reduces the levels of malondialdehyde and increases the levels of superoxide dismutase, nitric oxide release and endothelial nitric oxide synthase mRNA, but has no significant effect on inducible nitric oxide synthase mRNA levels.
  
  
  CONCLUSIONS
  These results demonstrate that allicin has powerful effects in protecting HUVECs from apoptosis and suggest that protection occurs via a mechanism involving the protection from H2O2-mediated oxidative stress.
authors.forename: Sisi
authors.initials: S
authors.lastname: Chen
authors.forename: Yuye
authors.initials: Y
authors.lastname: Tang
authors.forename: Ying
authors.initials: Y
authors.lastname: Qian
authors.forename: Ruyi
authors.initials: R
authors.lastname: Chen
authors.affiliation: College of Life Science, Zhejiang Chinese Medical University, Hangzhou 310053, China. daizimu3@hotmail.com.
authors.forename: Lin
authors.initials: L
authors.lastname: Zhang
authors.forename: Like
authors.initials: L
authors.lastname: Wo
authors.forename: Hui
authors.initials: H
authors.lastname: Chai
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D053148:Caspase 3 / Q000378:metabolism; D004220:Disulfides; D005737:Garlic / Q000737:chemistry*; D061307:Human Umbilical Vein Endothelial Cells / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D006861:Hydrogen Peroxide / Q000633:toxicity; D008315:Malondialdehyde / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism; D052247:Nitric Oxide Synthase Type II / Q000378:metabolism; D018384:Oxidative Stress / Q000187:drug effects*; D010936:Plant Extracts / Q000494:pharmacology*; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism; D020011:Protective Agents / Q000494:pharmacology*; D013441:Sulfinic Acids / Q000494:pharmacology*; D051028:bcl-2-Associated X Protein / Q000378:metabolism
chemical_list: D004220:Disulfides; D010936:Plant Extracts; D020011:Protective Agents; D013441:Sulfinic Acids; D051028:bcl-2-Associated X Protein; D009569:Nitric Oxide; C006452:allicin; D008315:Malondialdehyde; D006861:Hydrogen Peroxide; D052247:Nitric Oxide Synthase Type II; D011065:Poly(ADP-ribose) Polymerases; D053148:Caspase 3