title: Effects of dietary antioxidant supplementation before and after oral acetaminophen challenge in cats.
abstract: OBJECTIVE
  To determine effects of lipoic acid, vitamin E, and cysteine before and after oxidant challenge in cats.
  
  
  METHODS
  24 sexually intact adult cats.
  
  
  METHODS
  Cats were allocated into 4 equal groups. For 25 weeks, group A was fed a control dry diet and groups B, C, and D received this diet supplemented with vitamin E (2200 U/kg [dry matter basis {DMB}]) plus cysteine (9.5 g/kg [DMB]), lipoate (150 mg/kg [DMB]), or all 3 antioxidants together, respectively. Weights were measured every 3 days and venous blood obtained every 5 weeks for CBC; serum biochemical analyses; lymphocyte blastogenesis; thiobarbituric acid reactive substances concentration; and concentrations of plasma protein carbonyl, 8-OH d-guanosine, blood glutathione, plasma amino acid, lipoate, and dihydrolipoate. At 15 weeks, all cats received acetaminophen (9 mg/kg, PO, once), clinical effects were observed, and methemoglobin concentrations were measured.
  
  
  RESULTS
  Lymphocyte blastogenesis increased transiently in group C and D cats. After acetaminophen administration, all groups had transient increases in methemoglobin within 4 hours and mild, brief facial edema; group C had decreased glutathione concentration and increased 8-OH d-guanosine concentration versus controls; and protein carbonyl concentration increased least for group B. Plasma lipoate and dihydrolipoate concentrations peaked by week 10 for groups C and D. Conclusions and Clinical Relevance-Lipoate, vitamin E, and cysteine did not have synergistic effects. Lipoate supplementation (150 mg/kg [DMB]) did not act as an antioxidant but appeared to enhance oxidant effects of acetaminophen. Vitamin E plus cysteine had protective effects.
authors.affiliation: Department of Clinical Sciences, College of Veterinary Medicine, The Ohio State University, Columbus, OH 43210, USA.
authors.forename: Ana S
authors.initials: AS
authors.lastname: Hill
authors.forename: Quinton R
authors.initials: QR
authors.lastname: Rogers
authors.forename: Sharron L
authors.initials: SL
authors.lastname: O'Neill
authors.forename: Mary M
authors.initials: MM
authors.lastname: Christopher
mesh_terms: D000080242:8-Hydroxy-2'-Deoxyguanosine / Q000031:analogs & derivatives; D000082:Acetaminophen / Q000008:administration & dosage / Q000494:pharmacology*; D018712:Analgesics, Non-Narcotic / Q000008:administration & dosage / Q000494:pharmacology*; D000818:Animals; D000975:Antioxidants / Q000008:administration & dosage*; D015415:Biomarkers / Q000097:blood; D002415:Cats; D002851:Chromatography, High Pressure Liquid / Q000662:veterinary; D003545:Cysteine / Q000008:administration & dosage*; D019587:Dietary Supplements; D004359:Drug Therapy, Combination; D005260:Female; D005978:Glutathione / Q000097:blood / Q000187:drug effects; D006147:Guanine / Q000031:analogs & derivatives* / Q000097:blood; D008213:Lymphocyte Activation / Q000187:drug effects; D008214:Lymphocytes / Q000187:drug effects; D008297:Male; D008706:Methemoglobin / Q000032:analysis / Q000187:drug effects; D008063:Thioctic Acid / Q000008:administration & dosage* / Q000031:analogs & derivatives* / Q000097:blood; D014810:Vitamin E / Q000008:administration & dosage*
chemical_list: D018712:Analgesics, Non-Narcotic; D000975:Antioxidants; D015415:Biomarkers; D014810:Vitamin E; D000082:Acetaminophen; D006147:Guanine; C078307:8-oxo-7,8-dihydrodeoxyguanine; D008063:Thioctic Acid; C015144:dihydrolipoic acid; D000080242:8-Hydroxy-2'-Deoxyguanosine; D008706:Methemoglobin; D005978:Glutathione; D003545:Cysteine