The cortisol and androgen pathways cross-talk in high-temperature induced masculinization: 11β-hydroxysteroid dehydrogenase as a key enzyme.

JUAN I. FERNANDINO; RICARDO S. HATTORI; AI KIISHI; CARLOS A. STRÜSSMANN; GUSTAVO M. SOMOZA

Buenos Aires

Congreso; 7th International Symposium on Fish Endocrinology.; 2012

In many ectotherm species the gonadal fate is modulated by temperature early inlife (Temperature-Dependent Sex Determination, TSD). We have recently shownthat cortisol is involved in the TSD process of pejerrey, Odontesthes bonariensis.Thus, all larvae exposed to a male-producing temperature (MPT) after hatchingshowed increased whole-body cortisol and 11-ketotestosterone (11-KT) levels anddeveloped as males. In order to clarify the link between stress and masculinization,the expression of hsd11b2, glucocorticoid receptors gr1 and gr2, and androgenreceptors ar1 and ar2 was analyzed by RT-qPCR and in situ hybridization in larvaereared at MPT and FPT (female-PT) during the sex determination period. We alsoanalyzed the effects of cortisol treatment in larvae reared at MixPT (Mix sex-PT)and in adult testicular explants incubated in vitro. MPT and cortisol treatmentproduced significant increases in hsd11b2 mRNA expression. Also, gonadal explantsincubated in the presence of cortisol showed increased medium 11-KT levels. Takentogether these results suggest that cortisol promotes 11-KT production during hightemperature-induced masculinization by modulation of hsd11b2 expression andthus drives the morphogenesis of the testes.