title: Modulation of zymosan-induced peritonitis by riboflavin co-injection, pre-injection or post-injection in male Swiss mice.
abstract: OBJECTIVE
  We compared the effects of riboflavin pre-injection, co-injection and post-injection on several symptoms of zymosan-induced peritonitis in male Swiss mice. Additionally, the effects of i.p. injection of riboflavin itself were elucidated.
  
  
  METHODS
  Peritonitis was induced in Swiss mice (50 animals) by i.p. zymosan (Z; 40mg/kg) injection. Riboflavin (R; 0, 20, 50, or 100mg/kg) was applied either alone or in combination with zymosan. In the latter case riboflavin was administered either together with zymosan (R group), or 30min before zymosan (R-Z group), or 1h later (Z-R group). The nociceptive response was evaluated by counting body writhes. The peritoneal exudates retrieved 4h after the R or Z injection were analyzed for the numbers and apoptosis of polymorphonuclear leukocytes (PMNs), and levels of metalloproteinase 9 (MMP-9), nitric oxide, and inflammatory cytokines, IL-12p70, TNFα, MCP-1, IL-6, IL-10, IFNγ.
  
  
  RESULTS
  Riboflavin itself induced nociceptive-related body writhes and a moderate inflammatory response manifested by PMN influx and the release of some cytokines and MMP-9. In contrast, antinociceptive properties of riboflavin were significant in the ZR group co-injected with the lowest dose of riboflavin (ZR20). At the 4th hour of zymosan-induced peritonitis an intraperitoneal accumulation of PMNs was decreased in the riboflavin-treated groups and cytokine profiles were modified according to riboflavin dose and the time of injection.
  
  
  CONCLUSIONS
  Riboflavin itself induces low-grade nociception and inflammation while its effects on zymosan-induced inflammation are dependent on the dose and time of its application: either before or during inflammation.
authors.affiliation: Department of Ergonomics and Exercise Physiology, Faculty of Health Science, Jagiellonian University Medical College, Grzegorzecka 20, 31-531 Krakow, Poland. agnieszka.mazur@uj.edu.pl
authors.forename: Agnieszka Irena
authors.initials: AI
authors.lastname: Mazur-Bialy
authors.forename: Elzbieta
authors.initials: E
authors.lastname: Kolaczkowska
authors.forename: Barbara
authors.initials: B
authors.lastname: Plytycz
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D016207:Cytokines / Q000378:metabolism; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D007249:Inflammation / Q000188:drug therapy* / Q000503:physiopathology; D018836:Inflammation Mediators / Q000378:metabolism; D007274:Injections, Intraperitoneal; D008297:Male; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism; D051379:Mice; D009504:Neutrophils / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism; D059225:Nociception / Q000187:drug effects*; D010538:Peritonitis / Q000188:drug therapy* / Q000503:physiopathology; D012256:Riboflavin / Q000008:administration & dosage / Q000494:pharmacology*; D013997:Time Factors; D015054:Zymosan / Q000633:toxicity
chemical_list: D016207:Cytokines; D018836:Inflammation Mediators; D009569:Nitric Oxide; D015054:Zymosan; D020780:Matrix Metalloproteinase 9; D012256:Riboflavin