title: Oxidant-induced damage to equine erythrocytes from exposure to Pistacia atlantica, Pistacia terebinthus, and Pistacia chinensis.
abstract: Two horses were referred for methemoglobinemia and hemolytic anemia following 5 acute deaths in their herd from an unidentified toxin source. Horses have a greater risk than other mammalian species of developing methemoglobinemia and hemolytic anemia following ingestion of oxidizing toxins, due to deficiencies in the mechanisms that protect against oxidative damage in erythrocytes. Their susceptibility to oxidative erythrocyte damage is evident in the numerous cases of red maple (Acer rubrum) toxicosis. The suspected toxins causing A. rubrum toxicosis are tannic acid, gallic acid, and a metabolite of gallic acid, pyrogallol. These compounds can be found in a variety of plants, posing a risk to equine health. In order to quickly identify toxin sources, 2 rapid in vitro assays were developed to screen plant extracts for the ability to induce methemoglobin formation or cause hemolysis in healthy equine donor erythrocytes. The plant extract screening focused on 3 species of the genus Pistacia: P. atlantica, P. terebinthus, and P. chinensis, which were located in the horse pasture. Extracts of the seeds and leaves of each species induced methemoglobin formation and resulted in hemolysis, with seed extracts having greater potency. The in vitro assays used in the current study provide a useful diagnostic method for the rapid identification of oxidizing agents from unidentified sources. There is no effective treatment for oxidative erythrocyte damage in horses, making rapid identification and removal of the source essential for the prevention of poisoning.
authors.affiliation: Department of Molecular Biosciences (Walter, Moore, Puschner), School of Veterinary Medicine, University of California, Davis, CAVeterinary Medical Teaching Hospital (Bozorgmanesh), School of Veterinary Medicine, University of California, Davis, CADepartment of Medicine and Epidemiology (Magdesian), School of Veterinary Medicine, University of California, Davis, CACalifornia Animal Health and Food Safety Laboratory System (Puschner, Woods), School of Veterinary Medicine, University of California, Davis, CA.
authors.forename: Kyla M
authors.initials: KM
authors.lastname: Walter
authors.affiliation: Department of Molecular Biosciences (Walter, Moore, Puschner), School of Veterinary Medicine, University of California, Davis, CAVeterinary Medical Teaching Hospital (Bozorgmanesh), School of Veterinary Medicine, University of California, Davis, CADepartment of Medicine and Epidemiology (Magdesian), School of Veterinary Medicine, University of California, Davis, CACalifornia Animal Health and Food Safety Laboratory System (Puschner, Woods), School of Veterinary Medicine, University of California, Davis, CA.
authors.forename: Caroline E
authors.initials: CE
authors.lastname: Moore
authors.affiliation: Department of Molecular Biosciences (Walter, Moore, Puschner), School of Veterinary Medicine, University of California, Davis, CAVeterinary Medical Teaching Hospital (Bozorgmanesh), School of Veterinary Medicine, University of California, Davis, CADepartment of Medicine and Epidemiology (Magdesian), School of Veterinary Medicine, University of California, Davis, CACalifornia Animal Health and Food Safety Laboratory System (Puschner, Woods), School of Veterinary Medicine, University of California, Davis, CA.
authors.forename: Rana
authors.initials: R
authors.lastname: Bozorgmanesh
authors.affiliation: Department of Molecular Biosciences (Walter, Moore, Puschner), School of Veterinary Medicine, University of California, Davis, CAVeterinary Medical Teaching Hospital (Bozorgmanesh), School of Veterinary Medicine, University of California, Davis, CADepartment of Medicine and Epidemiology (Magdesian), School of Veterinary Medicine, University of California, Davis, CACalifornia Animal Health and Food Safety Laboratory System (Puschner, Woods), School of Veterinary Medicine, University of California, Davis, CA.
authors.forename: K Gary
authors.initials: KG
authors.lastname: Magdesian
authors.affiliation: Department of Molecular Biosciences (Walter, Moore, Puschner), School of Veterinary Medicine, University of California, Davis, CAVeterinary Medical Teaching Hospital (Bozorgmanesh), School of Veterinary Medicine, University of California, Davis, CADepartment of Medicine and Epidemiology (Magdesian), School of Veterinary Medicine, University of California, Davis, CACalifornia Animal Health and Food Safety Laboratory System (Puschner, Woods), School of Veterinary Medicine, University of California, Davis, CA.
authors.forename: Leslie W
authors.initials: LW
authors.lastname: Woods
authors.affiliation: Department of Molecular Biosciences (Walter, Moore, Puschner), School of Veterinary Medicine, University of California, Davis, CAVeterinary Medical Teaching Hospital (Bozorgmanesh), School of Veterinary Medicine, University of California, Davis, CADepartment of Medicine and Epidemiology (Magdesian), School of Veterinary Medicine, University of California, Davis, CACalifornia Animal Health and Food Safety Laboratory System (Puschner, Woods), School of Veterinary Medicine, University of California, Davis, CA bpuschner@ucdavis.edu.
authors.forename: Birgit
authors.initials: B
authors.lastname: Puschner
mesh_terms: D000743:Anemia, Hemolytic / Q000139:chemically induced / Q000175:diagnosis / Q000662:veterinary*; D000818:Animals; D004912:Erythrocytes / Q000187:drug effects*; D006734:Horse Diseases / Q000139:chemically induced / Q000175:diagnosis*; D006736:Horses; D008708:Methemoglobinemia / Q000139:chemically induced / Q000175:diagnosis / Q000662:veterinary*; D027927:Pistacia / Q000737:chemistry / Q000506:poisoning*; D010936:Plant Extracts / Q000032:analysis / Q000506:poisoning / Q000633:toxicity; D018515:Plant Leaves / Q000737:chemistry / Q000506:poisoning; D012639:Seeds / Q000737:chemistry / Q000506:poisoning; D013045:Species Specificity
chemical_list: D010936:Plant Extracts
keywords:  Pistacia spp.; Equine; hemolysis; methemoglobin; oxidants; poisoning