Effects of temperature extreme events and increased mean temperature on immune response and its endocrine and molecular mediators in toads (Rhinella diptycha)

• Grant number: 23/00235-0
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• Start date: June 01, 2023
• End date: June 30, 2027
• Field of knowledge: Biological Sciences - Physiology - Compared Physiology
• Principal Investigator: Fernando Ribeiro Gomes
• Grantee: Alan Siqueira Lima
• Host Institution: Instituto de Biociências (IB). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Currently, investigations regarding effects of climate change over animals are increasing in quantity and quality. However, these investigations are usually focused on effects of increased mean temperature over time, while extreme climatic events (ECEs) remains poorly studied. ECEs are quickly increasing in amplitude, duration, and frequency and have confirmed effects on multiple levels of biological organization. Highly deleterious effects over physiological functions in multiple species have been described, including impacts over immunity. The present study will investigate the potential stress caused by alterations in amplitude and duration of ECEs and its repercussions over endocrine mediators of stress response (glucocorticoids and catecholamines), molecular modulators (cytokines and heat-shock proteins) and immunological functions (phagocytic activity, plasma bacterial killing ability, and neutrophil:lymphocyte ratio) in toads (Rhinella dypticha). This study will be of great relevance to better understand the physiological processes underpinning deleterious effects of ECEs. This is especially important for amphibians, which population are facing declines at high rates associated with climate change and novel infectious diseases. (AU)