title: Toxoplasma gondii infection enhances testicular steroidogenesis in rats.
abstract: The protozoan parasite Toxoplasma gondii enhances the sexual attractiveness of infected male rats and attenuates the innate fear of cat odour in infected individuals. These behavioural changes plausibly lead to greater transmission of parasites through sexual and trophic routes, respectively. Testosterone, a testicular steroid, is known to reduce fear and enhance sexual attractiveness in males. Here, we show that Toxoplasma gondii infection enhances expression of genes involved in facilitating synthesis of testosterone, resulting in greater testicular testosterone production in male rats. In several species, testosterone mediates trade-offs between sexually selected traits and life history decisions. Augmentation of testosterone synthesis by Toxoplasma gondii suggests that parasites may manipulate these trade-offs in rats.
authors.affiliation: School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore, 637551, Singapore.
authors.forename: Audrey
authors.initials: A
authors.lastname: Lim
authors.forename: Vineet
authors.initials: V
authors.lastname: Kumar
authors.forename: Shantala A
authors.initials: SA
authors.lastname: Hari Dass
authors.forename: Ajai
authors.initials: A
authors.lastname: Vyas
mesh_terms: D000818:Animals; D001522:Behavior, Animal; D005239:Fear; D005786:Gene Expression Regulation; D006790:Host-Parasite Interactions; D008297:Male; D009919:Orchiectomy; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D011974:Receptors, LH / Q000235:genetics / Q000378:metabolism; D013737:Testis / Q000378:metabolism* / Q000469:parasitology; D013739:Testosterone / Q000096:biosynthesis* / Q000097:blood; D014122:Toxoplasma; D014124:Toxoplasmosis, Animal / Q000378:metabolism*
chemical_list: D012333:RNA, Messenger; D011974:Receptors, LH; D013739:Testosterone