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Journal of Biomedicine and Biotechnology
Volume 2010 (2010), Article ID 591079, 10 pages
Research Article

Progesterone Induces Scolex Evagination of the Human Parasite Taenia solium: Evolutionary Implications to the Host-Parasite Relationship

1Departamento de Biología, Facultad de Química, Universidad Nacional Autónoma de México, AP 70228, 04510 México, DF, Mexico
2Departamento de Inmunología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, AP 70228, 04510 México, DF, Mexico
3Instituto de Biología, Universidad Nacional Autónoma de México, 04510 México, DF, Mexico

Received 30 July 2009; Accepted 14 September 2009

Academic Editor: Luis I. Terrazas

Copyright © 2010 Galileo Escobedo et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Taenia solium cysticercosis is a health problem in underdeveloped and developed countries. Sex hormones are involved in cysticercosis prevalence in female and male pigs. Here, we evaluated the effects of progesterone and its antagonist RU486 on scolex evagination, which is the initial step in the development of the adult worm. Interestingly, progesterone increased T. solium scolex evagination and worm growth, in a concentration-independent pattern. Progesterone effects could be mediated by a novel T. solium progesterone receptor (TsPR), since RU486 inhibits both scolex evagination and worm development induced by progesterone. Using RT-PCR and western blot, sequences related to progesterone receptor were detected in the parasite. A phylogenetic analysis reveals that TsPR is highly related to fish and amphibian progesterone receptors, whereas it has a distant relation with birds and mammals. Conclusively, progesterone directly acts upon T. solium cysticerci, possibly through its binding to a progesterone receptor synthesized by the parasite.