title: Acid sphingomyelinase inhibition protects mice from lung edema and lethal Staphylococcus aureus sepsis.
abstract: Pulmonary edema associated with increased vascular permeability is a severe complication of Staphylococcus aureus-induced sepsis and an important cause of human pathology and death. We investigated the role of the mammalian acid sphingomyelinase (Asm)/ceramide system in the development of lung edema caused by S. aureus. Our findings demonstrate that genetic deficiency or pharmacologic inhibition of Asm reduced lung edema in mice infected with S. aureus. The Asm/ceramide system triggered the formation of superoxide, resulting in degradation of tight junction proteins followed by lung edema. Treatment of infected mice with amitriptyline, a potent inhibitor of Asm, protected mice from lung edema caused by S. aureus, but did not reduce systemic bacterial numbers. In turn, treatment with antibiotics reduced bacterial numbers but did not protect mice from lung edema. In contrast, only the combination of antibiotics and amitriptyline inhibited both pulmonary edema and bacteremia protecting mice from lethal sepsis and lung dysfunction suggesting the combination of both drugs as novel treatment option for sepsis.
  
  
  CONCLUSIONS
  Antibiotics are often insufficient to cure S. aureus-induced sepsis. S. aureus induces lung edema via the Asm/ceramide system. Genetic deficiency of Asm inhibits lung dysfunction upon infection with S. aureus. Pharmacologic inhibition of Asm reduces lung edema induced by S. aureus. Antibiotics plus amitriptyline protect mice from lung edema and lethal S. aureus sepsis.
authors.affiliation: Department of Molecular Biology, University of Duisburg-Essen, Hufelandstrasse 55, 45122, Essen, Germany.
authors.forename: Huiming
authors.initials: H
authors.lastname: Peng
authors.forename: Cao
authors.initials: C
authors.lastname: Li
authors.forename: Stephanie
authors.initials: S
authors.lastname: Kadow
authors.forename: Brian D
authors.initials: BD
authors.lastname: Henry
authors.forename: Jörg
authors.initials: J
authors.lastname: Steinmann
authors.forename: Katrin Anne
authors.initials: KA
authors.lastname: Becker
authors.forename: Andrea
authors.initials: A
authors.lastname: Riehle
authors.forename: Natalie
authors.initials: N
authors.lastname: Beckmann
authors.forename: Barbara
authors.initials: B
authors.lastname: Wilker
authors.forename: Pin-Lan
authors.initials: PL
authors.lastname: Li
authors.forename: Timothy
authors.initials: T
authors.lastname: Pritts
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Edwards
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhang
authors.forename: Erich
authors.initials: E
authors.lastname: Gulbins
authors.forename: Heike
authors.initials: H
authors.lastname: Grassmé
mesh_terms: D000639:Amitriptyline / Q000627:therapeutic use; D000818:Animals; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D002518:Ceramides / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000627:therapeutic use; D055786:Gene Knockout Techniques; D008168:Lung / Q000187:drug effects* / Q000378:metabolism / Q000382:microbiology / Q000473:pathology; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D011654:Pulmonary Edema / Q000235:genetics / Q000382:microbiology / Q000473:pathology / Q000628:therapy*; D018805:Sepsis / Q000235:genetics / Q000382:microbiology / Q000473:pathology / Q000628:therapy*; D013108:Sphingomyelin Phosphodiesterase / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D013203:Staphylococcal Infections / Q000150:complications / Q000235:genetics / Q000473:pathology / Q000628:therapy*; D013211:Staphylococcus aureus / Q000187:drug effects*; D013481:Superoxides / Q000037:antagonists & inhibitors / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D002518:Ceramides; D004791:Enzyme Inhibitors; D013481:Superoxides; D000639:Amitriptyline; C112980:acid sphingomyelinase-1; D013108:Sphingomyelin Phosphodiesterase