Stress Response, Immunity, and Organ Mass in Toads (Rhinella diptycha) Living in Metal-Contaminated Areas

Autor(es)

Vasconcelos-Teixeira, Ronyelle ^[1] ; Titon, Stefanny C. M. ^{[1, 2]} ; Titon Jr, Braz ; Pompeo, Marcelo L. M. ^[3] ; Gomes, Fernando R. ^[1] ; Assis, Vania R. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Biosci, Dept Physiol, Lab Behav & Evolutionary Physiol, Lab 206, Sao Paulo - Brazil

^[2] Univ Sao Paulo, Inst Biosci, Dept Physiol, Lab Dis & Drug Associated Receptors Knowledge, Sao Paulo - Brazil

^[3] Univ Sao Paulo, Inst Biosci, Dept Ecol, Lab Limnol, Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: BIOLOGICAL TRACE ELEMENT RESEARCH; v. 200, n. 2, p. 800-811, FEB 2022.
• Citações Web of Science: 1

Resumo

Mining is one of the main activities that drive the economy of Brazil. Mining activity is associated with risk of contamination of environment and local fauna by metals. Amphibians have a life cycle that requires a transition between aquatic and terrestrial environments, increasing their vulnerability to metal contamination in the water and substrate. Metals are ubiquitous, with high bioaccumulative and biomagnifying potential, and may lead to immune and endocrine disruption. In this study, we analyzed two different components of the innate immune response, bacterial killing ability (BKA) and phytohemagglutinin edema (PHA), and two stress biomarkers, corticosterone plasma levels (CORT) and the neutrophil to lymphocyte ratio (N:L), of toads (Rhinella diptycha) living in places contaminated by metals. Blood samples were collected pre- and post-restraint (1h), followed by an immune challenge with PHA and tissue collection (liver, spleen, and kidneys). Toads liver metal bioaccumulation did not correlate with the immune response or stress biomarkers. Post-restraint, animals had increased CORT and reduced BKA, independently of the collection site, and these variables were not correlated with liver metal bioaccumulation. Interestingly, toads with the larger spleen (immune organ) showed increased N:L post-restraint and greater edema after the PHA challenge. Our results indicate that toads living in metal-contaminated environments responded to acute stressor, activating the hypothalamic-pituitary-interrenal axis and the immune response. Keep tracking the physiological variables of these animals and the presence of metals in the environment and tissues should provide valuable health status indicators for the population, which is vital for proposing amphibian conservation strategies in these areas. (AU)

• Processo FAPESP: 14/16320-7 - Impactos das mudanças climáticas e ambientais sobre a fauna: uma abordagem integrativa
• Beneficiário: Carlos Arturo Navas Iannini
• Modalidade de apoio: Auxílio à Pesquisa - Programa de Pesquisa sobre Mudanças Climáticas Globais - Temático