RT Journal Article T1 Combined antiparasitic and anti‐inflammatory effects of the natural polyphenol curcumin on turbot scuticociliatosis A1 Mallo Seijas, Natalia A1 Felipe González, Ana Paula de A1 Folgueira López, Iria A1 Sueiro Benavides, Rosa Ana A1 Lamas Fernández, Jesús A1 Leiro Vidal, José Manuel K1 Philasterides dicentrarchi K1 Curcumin K1 Proteases K1 S-adenosyl-L-homocysteine hydrolase K1 Cathepsin L-like K1 Leishmanolysin AB The histiophagous scuticociliate Philasterides dicentrarchi is the aetiological agent of scuticociliatosis, a parasitic disease of farmed turbot. Curcumin, a polyphenol from Curcuma longa (turmeric), is known to have antioxidant and anti-inflammatory properties. We investigated the in vitro effects of curcumin on the growth of P. dicentrarchi and on the production of pro-inflammatory cytokines in turbot leucocytes activated by parasite cysteine proteases. At 100 μm, curcumin had a cytotoxic effect and completely inhibited the growth of the parasite. At 50 μm, curcumin inhibited the protease activity of the parasite and expression of genes encoding two virulence-associated proteases: leishmanolysin-like peptidase and cathepsin L-like. At concentrations between 25 and 50 μm, curcumin inhibited the expression of S-adenosyl-L-homocysteine hydrolase, an enzyme involved in the biosynthesis of the amino acids methionine and cysteine. At 100 μm, curcumin inhibited the expression of the cytokines tumour necrosis factor-alpha (TNF-α) and interleukin-1 beta (IL-1β) produced in turbot leucocytes activated by parasite proteases. Results show that curcumin has a dual effect on scuticociliatosis: an antiparasitic effect on the catabolism and anabolism of ciliate proteins, and an anti-inflammatory effect that inhibits the production of proinflammatory cytokines in the host. The present findings suggest the potential usefulness of this polyphenol in treating scuticociliatosis PB Wiley SN 1365-2761 YR 2017 FD 2017-01-04 LK http://hdl.handle.net/10347/18168 UL http://hdl.handle.net/10347/18168 LA eng NO Mallo, N. , DeFelipe, A. P., Folgueira, I. , Sueiro, R. A., Lamas, J. and Leiro, J. M. (2017), Combined antiparasitic and anti‐inflammatory effects of the natural polyphenol curcumin on turbot scuticociliatosis. J Fish Dis, 40: 205- 217. doi:10.1111/jfd.12503 NO This is the peer reviewed version of the following article: Mallo, N. , DeFelipe, A. P., Folgueira, I. , Sueiro, R. A., Lamas, J. and Leiro, J. M. (2017), Combined antiparasitic and anti‐inflammatory effects of the natural polyphenol curcumin on turbot scuticociliatosis. J Fish Dis, 40: 205217. doi:10.1111/jfd.12503, which has been published in final form at https://doi.org/10.1111/jfd.12503. This article may be used for noncommercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions NO This work was financially supported by the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 634429 (PARAFISHCONTROL) and by the Ministerio de Economía y Competitividad (Spain) under grant agreement AGL2014-57125-R DS Minerva RD 28 abr 2026