Involvement of tumour necrosis factor-alpha in Clostridium perfringens beta-toxin-induced plasma extravasation in mice.
OBJECTIVE
Clostridium perfringens beta-toxin, an important agent of necrotic enteritis, causes plasma extravasation due to the release of a tachykinin NK(1) receptor agonist in mouse skin. In this study, we investigated the role of cytokines in beta-toxin-induced plasma extravasation.


METHODS
Male Balb/c, C3H/HeN and C3H/HeJ mice were anaesthetized with pentobarbitone and beta-toxin was injected i.d. into shaved dorsal skin. SR140333, capsaicin, chlorpromazine and pentoxifylline were given as pretreatment when required before the injection of the toxin. Cytokines in the dorsal skin were measured by ELISA.


RESULTS
Injection (i.d.) of beta-toxin induced a dose-dependent increase in dermal TNF-alpha and interleukin (IL)-1beta levels with a concomitant increase in plasma extravasation, but not the release of IL-6. SR140333 and capsaicin significantly inhibited the toxin-induced release of TNF-alpha and IL-1beta. The plasma extravasation and the release of TNF-alpha induced by beta-toxin were significantly inhibited by chlorpromazine and pentoxifylline which inhibit the release of TNF-alpha. The toxin-induced plasma extravasation in mouse skin was attenuated by pretreatment with a monoclonal antibody against TNF-alpha, but not anti-IL-1beta. Furthermore, the toxin caused an increase in plasma extravasation in both C3H/HeN (TLR4-intact) and C3H/HeJ (TLR4-deficient) mice. In C3H/HeN mice, the toxin-induced leakage was not inhibited by pretreatment with anti-TLR4/MD-2 antibody.


CONCLUSIONS
These observations show that beta-toxin-induced plasma extravasation in mouse skin is related to the release of TNF-alpha via the mechanism involving tachykinin NK(1) receptors, but not via TLR4.
Nagahama
M
M
Department of Microbiology, Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Tokushima, Japan.
Kihara
A
A
Kintoh
H
H
Oda
M
M
Sakurai
J
J
D000818:Animals; D001427:Bacterial Toxins / Q000008:administration & dosage / Q000494:pharmacology / Q000633:toxicity*; D004305:Dose-Response Relationship, Drug; D004797:Enzyme-Linked Immunosorbent Assay; D053583:Interleukin-1beta / Q000187:drug effects / Q000378:metabolism; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008809:Mice, Inbred C3H; D010949:Plasma / Q000187:drug effects* / Q000378:metabolism; D018040:Receptors, Neurokinin-1 / Q000187:drug effects / Q000378:metabolism; D012867:Skin / Q000187:drug effects / Q000378:metabolism; D051197:Toll-Like Receptor 4 / Q000187:drug effects / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000187:drug effects* / Q000378:metabolism
D001427:Bacterial Toxins; C031884:CPB protein, Clostridium perfringens; D053583:Interleukin-1beta; D018040:Receptors, Neurokinin-1; D051197:Toll-Like Receptor 4; D014409:Tumor Necrosis Factor-alpha