title: Aspirin Action in Endothelial Cells: Different Patterns of Response Between Chemokine CX3CL1/CX3CR1 and TNF-α/TNFR1 Signaling Pathways.
abstract: OBJECTIVE
  TNF-α induces fractalkine (CX3CL1) and its receptor CX3CR1 in endothelial cells through NF-қB activation. NF-қB inhibitors may reduce the expression of CX3CL1, and modulation of the CX3CL1/CX3CR1 signaling was proposed as a new target for aspirin. We examined the effects of aspirin on CX3CL1 and TNF-α production, as well as CX3CR1 and TNFR1 expression.
  
  
  METHODS
  HUVECs isolated after term pregnancies (N = 28) were cultured in vitro. Lipopolysaccharide (1 μg/ml) was used as CX3CL1 inducer. HUVECs were exposed to six different concentrations of aspirin (between 1.0 and 6.0 mM) during 7 days. The levels of CX3CL1 and TNF-α in the culture media were measured using ELISA. After termination of the cultures, mean expressions of CX3CR1 and TNFR1 were examined in the immunostained paraffin sections using quantitative immunohistochemistry.
  
  
  RESULTS
  Aspirin significantly (p <  .05) decreased CX3CL1 production, and the mean decrease in CX3CL1 production was inversely proportional to increased (p < 0.05) expression of CX3CR1. The combined mean CX3CL1 concentrations, including all time points, equaled 782.18 ± 74.4 pg/ml in aspirin treated HUVECs compared to a total concentration of 2467.53 ± 127.5 pg/ml combined from the respective time points in the controls. An inhibition of TNF-α production in HUVECs after pretreatment with aspirin was observed. Unlike in the case of CX3CR1 expression, there were no signs of TNFR1 upregulation.
  
  
  CONCLUSIONS
  Autoregulation between CX3CL1 and CX3CR1 may explain overexpression of CX3CR1 as the compensatory effect in aspirin-treated HUVECs. Inhibition of CX3CR1 could prevent thrombotic complications in the early period after discontinuation of aspirin.
authors.affiliation: Department of General & Experimental Pathology with Centre for Preclinical Research and Technology (CEPT), Medical University of Warsaw, ul. Pawinskiego 3C, 02-106, Warsaw, Poland, Dszukiewicz@hotmail.com.
authors.forename: Dariusz
authors.initials: D
authors.lastname: Szukiewicz
authors.forename: Malgorzata
authors.initials: M
authors.lastname: Wojciechowska
authors.forename: Anna
authors.initials: A
authors.lastname: Bilska
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Stangret
authors.forename: Grzegorz
authors.initials: G
authors.lastname: Szewczyk
authors.forename: Tarun Kumar
authors.initials: TK
authors.lastname: Mittal
authors.forename: Mateusz
authors.initials: M
authors.lastname: Watroba
authors.forename: Jan
authors.initials: J
authors.lastname: Kochanowski
mesh_terms: D001241:Aspirin / Q000494:pharmacology*; D000073883:CX3C Chemokine Receptor 1; D002478:Cells, Cultured; D054428:Chemokine CX3CL1 / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D042783:Endothelial Cells / Q000187:drug effects*; D006801:Humans; D019707:Receptors, Chemokine / Q000378:metabolism*; D047888:Receptors, Tumor Necrosis Factor, Type I / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects*; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism*; D015854:Up-Regulation / Q000187:drug effects
chemical_list: D000073883:CX3C Chemokine Receptor 1; C515538:CX3CL1 protein, human; C095235:CX3CR1 protein, human; D054428:Chemokine CX3CL1; D019707:Receptors, Chemokine; D047888:Receptors, Tumor Necrosis Factor, Type I; D014409:Tumor Necrosis Factor-alpha; D001241:Aspirin