title: Digoxin Inhibits Induction of Experimental Autoimmune Uveitis in Mice, but Causes Severe Retinal Degeneration.
abstract: OBJECTIVE
  Digoxin, a major medication for heart disease, was recently reported to have immunosuppressive capacity. Here, we determined the immunosuppressive capacity of digoxin on the development of experimental autoimmune uveitis (EAU) and on related immune responses.
  
  
  METHODS
  The B10.A mice were immunized with interphotoreceptor retinoid-binding protein (IRBP) and were treated daily with digoxin or vehicle control. On postimmunization day 14, the mouse eyes were examined histologically, while spleen cells were tested for cytokine production in response to IRBP and purified protein derivative. The immunosuppressive activity of digoxin was also tested in vitro, by its capacity to inhibit development of Th1 or Th17 cells. To investigate the degenerative effect of digoxin on the retina, naïve (FVB/N × B10.BR)F1 mice were similarly treated with digoxin and tested histologically and by ERG.
  
  
  RESULTS
  Treatment with digoxin inhibited the development of EAU, as well as the cellular response to IRBP. Unexpectedly, treatment with digoxin suppressed the production of interferon-γ to a larger extent than the production of interleukin 17. Importantly, digoxin treatment induced severe retinal degeneration, determined by histologic analysis with thinning across all layers of the retina. Digoxin treatment also induced dose-dependent vision loss monitored by ERG on naïve mice without induction of EAU.
  
  
  CONCLUSIONS
  Treatment of mice with digoxin inhibited the development of EAU and cellular immune response to IRBP. However, the treatment induced severe damage to the retina. Thus, the use of digoxin in humans should be avoided due to its toxicity to the retina.
authors.affiliation: Laboratory of Immunology National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States.
authors.forename: Samuel J H
authors.initials: SJ
authors.lastname: Hinshaw
authors.affiliation: Laboratory of Immunology National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States.
authors.forename: Osato
authors.initials: O
authors.lastname: Ogbeifun
authors.affiliation: Laboratory of Immunology National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States.
authors.forename: Wambui S
authors.initials: WS
authors.lastname: Wandu
authors.affiliation: Laboratory of Immunology National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States.
authors.forename: Cancan
authors.initials: C
authors.lastname: Lyu
authors.affiliation: Laboratory of Immunology National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States.
authors.forename: Guangpu
authors.initials: G
authors.lastname: Shi
authors.affiliation: Visual Function Core, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States.
authors.forename: Yichao
authors.initials: Y
authors.lastname: Li
authors.affiliation: Visual Function Core, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States.
authors.forename: Haohua
authors.initials: H
authors.lastname: Qian
authors.affiliation: Laboratory of Immunology National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States.
authors.forename: Igal
authors.initials: I
authors.lastname: Gery
mesh_terms: D000818:Animals; D003922:Diabetes Mellitus, Type 1; D004077:Digoxin / Q000494:pharmacology*; D004195:Disease Models, Animal; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005260:Female; D007111:Immunity, Cellular / Q000187:drug effects*; D051379:Mice; D012162:Retinal Degeneration / Q000209:etiology / Q000276:immunology / Q000517:prevention & control*; D012720:Severity of Illness Index; D014605:Uveitis / Q000150:complications / Q000188:drug therapy* / Q000276:immunology
chemical_list: D004791:Enzyme Inhibitors; D004077:Digoxin