Testosterone and corticosterone effects on the inflammatory response in toads (Rhinella icterica)

• Grant number: 20/15251-2
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): July 01, 2021
• Effective date (End): December 31, 2021
• Field of knowledge: Biological Sciences - Physiology - Compared Physiology
• Principal Investigator: Fernando Ribeiro Gomes
• Grantee: Stephani Domingues Menatto
• Host Institution: Instituto de Biociências (IB). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

The population decline in amphibians is mainly associated with climate change and infectious diseases. In this context, a better understanding of the immune system is necessary for us to understand how hormonal modulators are associated with mounting the inflammatory response in amphibians. Glucocorticoids, (corticosterone - CORT, the main glucocorticoid in amphibians), are widely known as the main mediators of the stress response, participating in the modulation of immune functions during the stress response. Additionally, androgens such as testosterone (T) also have immunomodulatory effects on different aspects of the immune response, such as, the production of cytokines and the humoral response in vertebrates. Studies of the isolated effects of CORT and T are scarce and those investigating the use of both hormones in the inflammatory assemblage in amphibians are unknown. Thus, the objective of this project is to investigate the immunomodulatory effects of the acute treatment of CORT and T on the inflammatory response of toads (Rhinella icterica) submitted to an immune challenge with lipopolysaccharide (LPS). We will evaluate components of the innate immune response and hormonal mediators of the inflammatory response in toads submitted to an immune challenge with LPS previously treated with CORT and T, in order to better understand the relationship between these hormones and the inflammatory response in anurans. (AU)