Seasonal Patterns of Variation in Steroid Plasma Levels and Immune Parameters in Anurans from Brazilian Semiarid Area

Autor(es)

Madelaire, Carla Bonetti ; Sokolova, Inna ; Gomes, Fernando Ribeiro

• Tipo de documento: Artigo Científico
• Fonte: PHYSIOLOGICAL AND BIOCHEMICAL ZOOLOGY; v. 90, n. 4, p. 415-433, JUL-AUG 2017.
• Citações Web of Science: 7

Resumo

Elevated androgens and glucocorticoids displayed by males during the reproductive season have been proposed to mediate a possible trade-off between reproduction and immunocompetence. Anurans living in arid and semiarid environments display a strong seasonal reproduction, which could accentuate the variation in physiological, immunological, and behavioral parameters. We studied covariation between steroid plasma levels, morphometric variables associated with body condition and immunity, leukocyte profile, parasite load, and response to an immunological challenge across different phases of the annual life-history cycle of three anuran species from a Brazilian semiarid area. Our results showed a seasonal pattern of covariation among leukocyte parameters, kidney mass, and steroid plasma levels, with higher values measured during the reproductive season, particularly when males were sampled during calling activity. Moreover, these anurans showed a stronger response to an immunological challenge during the reproductive period. The immunosuppression during the dry period was particularly evident for the species that aestivate, indicating that the availability of energetic resources might be an important factor determining seasonal variation in inflammatory response. Intensity of the helminth infection was associated with eosinophil count but showed a more complex pattern with regard to androgens levels. These data emphasize that variations in the intensity of helminth infection might be more closely related to specific aspects of the immune response than to the general seasonal patterns of variation in steroid plasma levels, total circulating leukocytes, and inflammatory response. (AU)

• Processo FAPESP: 11/03030-2 - Relação sazonal entre os níveis de testosterona, reprodução, imunocompetência e ocorrência de endoparasitas em anfíbios anuros da caatinga
• Beneficiário: Carla Bonetti Madelaire
• Modalidade de apoio: Bolsas no Brasil - Mestrado
• Processo FAPESP: 10/52290-4 - Relação sazonal entre os níveis de testosterona, reprodução, imunocompetência e ocorrência de endoparasitas em anfíbios anuros da Caatinga
• Beneficiário: Fernando Ribeiro Gomes
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 14/50643-8 - Effects of extreme seasonality on metabolism and immunity of amphibians in a tropical semi-arid zone
• Beneficiário: Fernando Ribeiro Gomes
• Modalidade de apoio: Auxílio à Pesquisa - Regular