Immunomodulatory effects of acute stress in toads from Genus Rhinella

• Grant number: 15/23801-4
• Support type: Scholarships in Brazil - Post-Doctorate
• Effective date (Start): June 01, 2016
• Effective date (End): July 31, 2019
• Field of knowledge: Biological Sciences - Physiology - Compared Physiology
• Principal researcher: Fernando Ribeiro Gomes
• Grantee: Vania Regina de Assis
• Home Institution: Instituto de Biociências (IB). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 14/16320-7 - Impacts of climate/environmental change on the fauna: an integrative approach, AP.PFPMCG.TEM
• Associated scholarship(s): 17/04802-5 - Long-term corticosterone treatment effects on stress and immune response in cane toads (Rhinella marina), BE.EP.PD

Abstract

Glucocorticoids modulate immune response in complex ways with both immuno-enhancing and immunosuppressive effects in vertebrates exposed to different stressors. Such bimodal effects have been associated with variation in duration and intensity of the stress response. Given that natural populations have been exposed to a multitude of stressors, a better understanding of the functional association between duration and intensity of the stress response, the resulting changes in glucocorticoid plasma levels and their impact on different aspects of immune response emerges as a keystone for vertebrate conservation strategies. We will investigate the interrelationships between corticosterone plasma levels (hereinafter referred to as CORT), and the innate immune response. Therefore, we will use the transdermal corticosterone application, to simulate the changes related to the increase in CORT in an acute stress event, in order to understand the immunomodulatory effects on different parameters of cellular and humoral immune response. Additionally, after a challenge with lipopolysaccharide (LPS), we will quantify the production of proteins related to the inflammatory immune response. Our study model will be male toads from genus Rhinella. We will test the following predictions: 1) Transdermal application of low concentrations of corticosterone should cause an increase in CORT and immune response; 2) Transdermal application of high concentrations of corticosterone should cause an even higher increase in CORT and decrease immune response; 3) After LPS challenge, animals that received corticosterone should have a decreased production of proteins related to inflammatory immune response than animals that did not receive the hormone; and 4) After LPS challenge animals that received low concentrations of corticosterone should have a higher production of proteins related to inflammatory immune response than animals that received higher concentrations of the hormone. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

TITON JUNIOR, BRAZ; TITON, STEFANNY CHRISTIE MONTEIRO; ASSIS, VANIA REGINA; BARSOTTI, ADRIANA MARIA GIORGI; VASCONCELOS-TEIXEIRA, RONYELLE; FERNANDES, PEDRO AUGUSTO CARLOS MAGNO; GOMES, FERNANDO RIBEIRO. LPS-induced immunomodulation and hormonal variation over time in toads. JOURNAL OF EXPERIMENTAL ZOOLOGY PART A-ECOLOGICAL AND INTEGRATIVE PHYSIOLOGY, v. 335, n. 6, p. 541-551, JUL 2021. Web of Science Citations: 0.