Inhibition of Tapeworm Thioredoxin and Glutathione Pathways by an Oxadiazole N-Oxide Leads to Reduced Mesocestoides vogae Infection Burden in Mice

Molecules

Vivian Pasquet¹  Hugo Bisio⁵  Gloria V. López³  Laura Romanelli-Cedrez⁵  Mariana Bonilla²  Jenny Salda༚⁴  Gustavo Salinas¹ 

[1] Cátedra de Inmunología, Instituto de Higiene, Facultad de Química, Universidad de la República, Avda, A. Navarro 3051, Montevideo 11400, Uruguay; E-Mail:;Redox Biology of Trypanosomes Laboratory, Institut Pasteur Montevideo, Mataojo 2020, Montevideo 11400, Uruguay; E-Mail:;Grupo de Química Medicinal, Laboratorio de Química Orgánica, Facultad de Química-Facultad de Ciencias, Universidad de la República, Iguá 4225, Montevideo 11400, Uruguay; E-Mail:;Laboratorio de Experimentación Animal, Depto de Ciencias Farmacéuticas, Facultad de Química, Universidad de la República, Avda. Gral. Flores 2124, Montevideo 11800, Uruguay; E-Mail:;Worm Biology Laboratory, Institut Pasteur Montevideo, Mataojo 2020, Montevideo 11400, Uruguay; E-Mails:

关键词: thioredoxin reductase;    glutathione reductase;    thioredoxin glutathione reductase;    oxadiazole N-oxide;    Mesocestoides;    tapeworms;   

DOI  :  10.3390/molecules200711793

来源: mdpi

【 摘 要 】

Parasitic flatworms cause serious infectious diseases that affect humans and livestock in vast regions of the world, yet there are few effective drugs to treat them. Thioredoxin glutathione reductase (TGR) is an essential enzyme for redox homeostasis in flatworm parasites and a promising pharmacological target. We purified to homogeneity and characterized the TGR from the tapeworm Mesocestoides vogae (syn. M. corti). This purification revealed absence of conventional TR and GR. The glutathione reductase activity of the purified TGR exhibits a hysteretic behavior typical of flatworm TGRs. Consistently, M. vogae genome analysis revealed the presence of a selenocysteine-containing TGR and absence of conventional TR and GR. M. vogae thioredoxin and glutathione reductase activities were inhibited by 3,4-bis(phenylsulfonyl)-1,2,5-oxadiazole N²-oxide (VL16E), an oxadiazole N-oxide previously identified as an inhibitor of fluke and tapeworm TGRs. Finally, we show that mice experimentally infected with M. vogae tetrathyridia and treated with either praziquantel, the reference drug for flatworm infections, or VL16E exhibited a 28% reduction of intraperitoneal larvae numbers compared to vehicle treated mice. Our results show that oxadiazole N-oxide is a promising chemotype in vivo and highlights the convenience of M. vogae as a model for rapid assessment of tapeworm infections in vivo.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.