title: Evaluation of the in vitro effects of aqueous black walnut extract on equine mononuclear cells.
abstract: OBJECTIVE
  To evaluate effects of black walnut extract (BWE) on equine mononuclear cells and determine whether BWE has direct proinflammatory effects.
  
  
  METHODS
  Mononuclear cells separated from blood samples from 8 horses.
  
  
  METHODS
  Aqueous BWE was prepared and processed to eliminate contamination with particulates and microbes. A Limulus amoebocyte lysate assay was used to detect lipopolysaccharide (LPS) contamination in the BWE. Mononuclear cells were incubated in minimal essential medium with or without the addition of 0.6% to 10% (vol/vol) BWE. These mononuclear cells were assessed for viability, activities of caspases 3 and 7, nitric oxide production, procoagulant activity, and tumor necrosis factor-α production. The effect of LPS on cellular responses induced by BWE was assessed by coincubation with 13 U of polymyxin B/mL; mononuclear cells incubated with LPS were used as a reference.
  
  
  RESULTS
  BWE did not cause loss of cell membrane integrity in mononuclear cells but did induce a dose-dependent increase in activities of caspases 3 and 7. Neither BWE nor LPS significantly induced production of nitric oxide. Both BWE and LPS induced comparable amounts of procoagulant activity and tumor necrosis factor-α production; coincubation with polymyxin B reduced the activity for BWE and LPS by 50% and approximately 100%, respectively.
  
  
  CONCLUSIONS
  Addition of BWE induced inflammatory activation of equine mononuclear cells, a portion of which was independent of the effects of LPS. Furthermore, BWE and LPS may work in concert to induce systemic inflammatory responses that contribute to the development of acute laminitis in horses.
authors.affiliation: Department of Population Health, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA. djhurley@uga.edu
authors.forename: David J
authors.initials: DJ
authors.lastname: Hurley
authors.forename: Londa J
authors.initials: LJ
authors.lastname: Berghaus
authors.forename: Katherine A E
authors.initials: KA
authors.lastname: Hurley
authors.forename: James N
authors.initials: JN
authors.lastname: Moore
mesh_terms: D000818:Animals; D001779:Blood Coagulation Factors / Q000378:metabolism; D053148:Caspase 3 / Q000378:metabolism; D053179:Caspase 7 / Q000378:metabolism; D005534:Foot Diseases / Q000139:chemically induced / Q000276:immunology / Q000662:veterinary*; D006734:Horse Diseases / Q000139:chemically induced / Q000209:etiology* / Q000276:immunology; D006736:Horses; D006799:Housing, Animal; D031324:Juglans / Q000737:chemistry*; D007963:Leukocytes, Mononuclear / Q000187:drug effects / Q000201:enzymology / Q000276:immunology*; D008070:Lipopolysaccharides / Q000276:immunology; D009569:Nitric Oxide / Q000378:metabolism; D010936:Plant Extracts / Q000737:chemistry*; D011112:Polymyxin B / Q000276:immunology / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis
chemical_list: D001779:Blood Coagulation Factors; D008070:Lipopolysaccharides; D010936:Plant Extracts; D014409:Tumor Necrosis Factor-alpha; C045071:leukocyte procoagulant activity; D009569:Nitric Oxide; D053148:Caspase 3; D053179:Caspase 7; D011112:Polymyxin B