Antisecretory factor suppresses intestinal inflammation andhypersecretion

Background—Antisecretory factor (AF) is a recentlyidentified regulatory protein which inhibits the intestinal fluidsecretion induced by cholera toxin.
Aims—To test the effect of AF on: (a)inflammation and hypersecretion induced by toxin A fromClostridium difficile; and (b) morphologicalchanges and hypersecretion induced by okadaic acid (the blue musseltoxin) in rat intestinal mucosa.
Methods—Morphological changes and fluidaccumulation were observed in intestinal loops challenged with 1 µgof toxin A or 3 µg of okadaic acid administered beforeor after injection of 0.1 µg of recombinant AF (rAF).
Results—The cytotoxic and inflammatory reactioncaused by toxin A was abolished after treatment with rAF given eitherintraveneously or intraluminally prior to the toxin or one hour afterthe toxin. The intestinal fluid response induced by toxin A and okadaicacid was reduced 55-80% by rAF. However, the characteristic increase in goblet cells at the tips of villi in the okadaic acid treated mucosawas not inhibited by rAF.
Conclusion—Results suggest that AF might beinvolved in protection against inflammation and in counteractingdehydration caused by enterotoxins. Both effects are probably mediatedvia the enteric nervous system.

Keywords:okadaic acid; Clostridiumdifficile toxin A; diarrhoea; neuropeptide; S5a; rat