title: Ginkgo biloba extract and aspirin synergistically attenuate activated platelet-induced ROS production and LOX-1 expression in human coronary artery endothelial cells.
abstract: OBJECTIVE
  In the present study, we investigated whether the therapeutic dosages of Ginkgo biloba extract (EGb) and Aspirin (ASP) might synergistically suppress oxidative stress through regulating the expressions of LOX-1 and phosphorylated p38MAPK (p-p38MAPK) in human coronary artery endothelial cells (HCAECs) ex vivo.
  
  
  METHODS
  HCAECs were stressed with activated platelets (2×10(8)/ml) and followed by ASP (1, 2 or 5 mmol/l), EGb (4, 40 or 400 μg/ml) and combinational (1 mmol/l ASP and 40μg/ml EGb) treatments in three groups for 12 h. Superoxide anion in HCAECs was measured with H2DCF-DA probe. The expressions of LOX-1 and p-p38MAPK were examined by Western blot.
  
  
  RESULTS
  After stimulation of activated platelets, intracellular superoxide anion was increased about 3-folds in HCAECs. Both ASP and EGb reduced superoxide anion in HCAECs in a dosage dependent manner. Combinational administration of ASP and EGb showed synergistic effect. By Western blot analysis, we were able to show that activated platelets markedly enhanced the expressions of LOX-1 and p-p38MAPK. Both ASP and EGb only inhibited LOX-1 expression in a concentration-dependent manner, but not p-p38MAPK. As expected, the combination of ASP and EGb markedly reduced not only the expression of LOX-1 but also the phosphorylation of p38MAPK.
  
  
  CONCLUSIONS
  Both EGb and ASP attenuate the oxidative stress of HCAECs stimulated by activated platelets ex vivo. It appears that the synergistic effect of EGb and ASP may correlate with the inhibition of ROS production, LOX-1 expression and p38MAPK phosphorylation.
authors.affiliation: Geriatrics Research Center, General Hospital of Air Force, PLA, Beijing 100142, China.
authors.forename: Xianguan
authors.initials: X
authors.lastname: Zhu
authors.forename: Zhongdong
authors.initials: Z
authors.lastname: Li
authors.forename: Cunxi
authors.initials: C
authors.lastname: Li
authors.forename: Jing
authors.initials: J
authors.lastname: Zhang
authors.forename: Zhikang
authors.initials: Z
authors.lastname: Zou
authors.forename: Jianchang
authors.initials: J
authors.lastname: Wang
mesh_terms: D001241:Aspirin / Q000494:pharmacology*; D002478:Cells, Cultured; D003331:Coronary Vessels / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004357:Drug Synergism; D042783:Endothelial Cells / Q000187:drug effects* / Q000378:metabolism; D004730:Endothelium, Vascular / Q000187:drug effects / Q000378:metabolism; D020441:Ginkgo biloba / Q000737:chemistry*; D006801:Humans; D018384:Oxidative Stress / Q000187:drug effects; D008517:Phytotherapy; D010936:Plant Extracts / Q000494:pharmacology*; D017382:Reactive Oxygen Species / Q000378:metabolism*; D051127:Scavenger Receptors, Class E / Q000378:metabolism*; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism
chemical_list: C495137:OLR1 protein, human; D010936:Plant Extracts; D017382:Reactive Oxygen Species; D051127:Scavenger Receptors, Class E; D048051:p38 Mitogen-Activated Protein Kinases; D001241:Aspirin