Strain-specific effects of riboflavin supplementation on zymosan-induced peritonitis in C57BL/6J, BALB/c and CBA mice.
OBJECTIVE
We investigated the effects of riboflavin (vitamin B2) on the kinetics of zymosan-induced peritonitis in three strains of mice.


METHODS
Peritonitis was induced in males of C57BL/6J, BALB/c and CBA mice by intraperitoneal injection of zymosan (40 mg/kg) or zymosan supplemented with riboflavin (50mg/kg). During the first 45 min of inflammation the pain symptoms were scored. At the selected time points (4, 6, 8, 10, 24, and 30 h) the mice were sacrificed and peritoneal exudates were retrieved. Leukocytes, among them polymorphonuclear cells (PMNs) and macrophages (Mac3(+) cells) were counted. Levels of inducible nitric oxide synthase (iNOS) were measured in cell pellets while supernatants were used for measurements of nitric oxide, cytokine/chemokines (IL-6, IL-10, MCP-1, IFNγ, TNF-α, and IL-12p70), and matrix metalloproteinase-9 (MMP-9).


RESULTS
A riboflavin ip injection induced pain symptoms itself, but reduced zymosan-induced pain in C57BL/6J and CBA strains of mice when coinjected with zymosan. In comparison with the mice injected with zymosan only, riboflavin coinjection prolonged inflammation in C57BL/6J mice due to prolonged macrophage accumulation; inhibited peritoneal leukocytes (PTL) accumulation in BALB/c due to inhibited influx of macrophages and PMNs; and inhibited PTL accumulation in CBA mice due to delayed PMN influx. These effects corresponded with the delayed (C57BL/6J) or inhibited (BALB/c and CBA) expression of iNOS in PTL lysates, and with the prolonged (C57BL/6) or inhibited (BALB/c) intraperitoneal accumulation of MMP-9. Moreover, cytokine accumulation was affected in a strain-specific way.


CONCLUSIONS
Riboflavin is antinociceptive during yeast-induced peritonitis, but its anti-inflammatory effects are strain-specific.
Department of Evolutionary Immunobiology, Institute of Zoology, Jagiellonian University, R. Ingardena 6, 30-060 Krakow, Poland. agnieszka.mazur@uj.edu.pl
Agnieszka Irena
AI
Mazur-Bialy
Anna
A
Majka
Lucja
L
Wojtas
Elzbieta
E
Kolaczkowska
Barbara
B
Plytycz
D000700:Analgesics / Q000494:pharmacology*; D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology*; D005786:Gene Expression Regulation / Q000187:drug effects; D007274:Injections, Intraperitoneal; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D010538:Peritonitis / Q000139:chemically induced* / Q000188:drug therapy; D012256:Riboflavin / Q000494:pharmacology*; D013045:Species Specificity; D015054:Zymosan
D000700:Analgesics; D000893:Anti-Inflammatory Agents; D015054:Zymosan; D012256:Riboflavin