In vitro activity of the nonsteroidal anti-inflammatory drug indomethacin on a scuticociliate parasite of farmed turbot.
The scuticociliatosis produced by the endoparasite Philasterides dicentarchi is a severe parasitic infection of farmed turbot (Scophthalmus maximus) characterized by several histopathological effects including extensive inflammation. Indomethacin is a nonsteroidal anti-inflammatory drug that specifically inhibits synthesis of the proinflammatory mediator prostaglandins. The effect of indomethacin on the in vitro growth of P. dicentrarchi was investigated. In vitro growth of the scuticociliate was significantly inhibited by treatment with 100 microM indomethacin for 48 h. Higher concentrations of indomethacin (mM levels) did not affect the gelatinolytic activity of the cysteine proteinases of P. dicentrarchi. In vitro treatment with 25, 50 or 100 microM indomethacin for 3 days did not significantly affect the enzymatic activity of cysteine proteinases, as assayed with p-nitroanilide as substrate. Immunoblot analysis with anti-cysteine proteinase antibodies revealed an increase in proteinase expression (molecular weights of 80, 32 and 40-45 kDa) in parasite lysates originating from in vitro cultures incubated with 25 microM indomethacin for 72 h. Degradation of genomic DNA of the ciliates was observed in cultures incubated with 100 microM indomethacin for 1, 3 and 7 days. The results suggest that indomethacin is capable of inhibiting in vitro growth of the scuticociliate P. dicentrarchi by a mechanism related to the induction of programmed cell death, without affecting the enzymatic activation of parasite proteinases, which demonstrates the potential therapeutic use of this drug in the control of turbot scuticociliatosis.
Paramá
Anabel
A
Departamento de Microbiología y Parasitología, Laboratorio de Parasitología, Instituto de Investigación y Análisis Alimentarios, Universidad de Santiago de Compostela, 15782 Santiago de Compostela, Spain.
Piazzon
María C
MC
Lamas
Jesús
J
Sanmartín
Manuel L
ML
Leiro
José
J
D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology*; D000913:Antibodies, Protozoan / Q000378:metabolism; D016770:Ciliophora Infections / Q000469:parasitology / Q000662:veterinary*; D003546:Cysteine Endopeptidases / Q000378:metabolism; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology; D053938:DNA Fragmentation / Q000187:drug effects; D016054:DNA, Protozoan / Q000032:analysis; D005393:Fish Diseases / Q000469:parasitology*; D005398:Fisheries; D005412:Flatfishes / Q000469:parasitology*; D006868:Hydrolysis / Q000187:drug effects; D007213:Indomethacin / Q000494:pharmacology*; D007930:Leucine / Q000031:analogs & derivatives / Q000494:pharmacology; D016802:Oligohymenophorea / Q000187:drug effects* / Q000201:enzymology / Q000254:growth & development
D000894:Anti-Inflammatory Agents, Non-Steroidal; D000913:Antibodies, Protozoan; D015853:Cysteine Proteinase Inhibitors; D016054:DNA, Protozoan; D003546:Cysteine Endopeptidases; D007930:Leucine; C024974:E 64; D007213:Indomethacin