Schistosoma mansoni: cercarial eicosanoid production and penetration response inhibited by esculetin and ibuprofen

Exp Parasitol. 1985 Aug;60(1):73-81. doi: 10.1016/s0014-4894(85)80024-2.


Cercariae of Schistosoma mansoni produce a wide variety of eicosanoids when stimulated by 3.3 mM linoleate. High-performance liquid chromatography indicated that 10(-5) M esculetin dramatically decreased eicosanoid production by cercariae. Ibuprofen (10(-4) M) also decreased eicosanoid production, but to a lesser extent. These results were confirmed by radioimmunoassay using time-dose curves for esculetin and time curves for ibuprofen. The results reported here indicated that, for cercariae, ibuprofen was neither a specific cyclo-oxygenase inhibitor, as has been reported for platelet and endothelial cells, nor was esculetin a specific inhibitor of lipoxygenase, as has been reported for platelets and mastocytoma cells. Rather, both drugs inhibited cyclo-oxygenase and lipoxygenase enzyme systems. Further, the data indicated that two forms of cyclo-oxygenase exist in cercariae (isozymes?), one initiating the conversion of gamma-dihomolinolenate into the 1-series prostaglandins and another acting on arachidonate forming the 2-series prostaglandins. The cyclo-oxygenase acting on arachidonate has a greater sensitivity to both ibuprofen and esculetin than the enzyme acting on gamma-dihomolinolenate. Cercarial lipoxygenases also varied greatly in their sensitivity to ibuprofen.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Arachidonate Lipoxygenases
  • Arachidonic Acids / metabolism*
  • Chromatography, High Pressure Liquid
  • Cyclooxygenase Inhibitors
  • Hydroxyeicosatetraenoic Acids / biosynthesis
  • Ibuprofen / pharmacology*
  • Larva / drug effects
  • Larva / metabolism
  • Larva / physiology
  • Leukotriene B4 / biosynthesis
  • Linoleic Acid
  • Linoleic Acids / metabolism
  • Lipoxygenase Inhibitors
  • Movement / drug effects
  • Prostaglandins E / biosynthesis
  • Radioimmunoassay
  • Schistosoma mansoni / drug effects
  • Schistosoma mansoni / metabolism*
  • Schistosoma mansoni / physiology
  • Umbelliferones / pharmacology*


  • Arachidonic Acids
  • Cyclooxygenase Inhibitors
  • Hydroxyeicosatetraenoic Acids
  • Linoleic Acids
  • Lipoxygenase Inhibitors
  • Prostaglandins E
  • Umbelliferones
  • Leukotriene B4
  • Linoleic Acid
  • Arachidonate Lipoxygenases
  • esculetin
  • Ibuprofen