Eicosanoid biosynthesis in an advanced deuterostomate invertebrate, the sea squirt (Ciona intestinalis)

Biochim Biophys Acta. 1999 Jan 4;1436(3):467-78. doi: 10.1016/s0005-2760(98)00153-2.


The eicosanoid generating potential of tunic, branchial basket, intestine, ovary and tadpole larvae from the sea squirt, Ciona intestinalis, was examined using a combination of reverse phase high performance liquid chromatography, gas chromatography-mass spectrometry and enzyme immunoassay. All organs examined synthesized the lipoxygenase products 12-hydroxyeicosapentaenoic acid (12-HEPE) and 8-HEPE implying that both 8- and 12-lipoxygenase activity are widely distributed in this species. In addition, tunic and branchial basket generated significant amounts of 8,15-diHEPE and smaller amounts of 8,15-dihydroxyeicosatetraenoic acid (8,15-diHETE), while tunic alone generated small amounts of conjugated tetraene-containing material with a UV chromophore and mass ion characteristic of a lipoxin-like compound. The broad range lipoxygenase inhibitors, esculetin and nordihydroguaiaretic acid, both caused a significant dose dependent inhibition of 12-HEPE and 8,15-diHEPE biosynthesis in tunic, while the specific 5-lipoxygenase inhibitor, REV-5901, and the specific 5-lipoxygenase activating protein inhibitor, MK-866, had no observable effect on the lipoxygenase profile of this tissue. Tunic, branchial basket, intestine and ovary all generated significant amounts of prostaglandin (PG) E and PGF immunoreactive material and smaller amounts of thromboxane B immunoreactive material as measured by enzyme immunoassay. The non-specific cyclooxygenase (COX) inhibitor, indomethacin, the selective COX-1 inhibitors, resveratrol and valerylsalicylate, and the specific COX-2 inhibitors, NS-398, etolodac and DFU (5,5-dimethyl-3-(3-fluorophenyl)-4-(4-methylsulphonyl) phenyl-2(5H)-furanone) all caused a significant dose dependent inhibition of the biosynthesis of PGE immunoreactive material. However, the specific COX-2 inhibitors were most effective, perhaps implying that a COX-2-like enzyme may be present in this species.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Chromatography, High Pressure Liquid
  • Ciona intestinalis / drug effects
  • Ciona intestinalis / metabolism*
  • Cyclooxygenase Inhibitors / pharmacology
  • Eicosanoids / biosynthesis*
  • Eicosanoids / chemistry
  • Eicosanoids / isolation & purification
  • Eicosapentaenoic Acid / analogs & derivatives
  • Eicosapentaenoic Acid / biosynthesis
  • Female
  • Gas Chromatography-Mass Spectrometry
  • Leukotriene B4 / analogs & derivatives
  • Leukotriene B4 / biosynthesis
  • Lipoxygenase Inhibitors / pharmacology
  • Molecular Structure
  • Tissue Distribution


  • Cyclooxygenase Inhibitors
  • Eicosanoids
  • Lipoxygenase Inhibitors
  • Leukotriene B4
  • 12-hydroxy-5,8,10,14,17-eicospentaenoic acid
  • 8,15-leukotriene B4
  • Eicosapentaenoic Acid