A game of two? Gene expression analysis of brain (cyp19a1b) and gonadal (cyp19a1a) aromatase in females of a Neotropical cichlid fish through the parental care period and removal of the offspring

RAMALLO, MARTIN; HONJI, RENATO; BIRBA, AGUSTINA; MORANDINI, LEONEL; VARELA, M.L.; GENOVESE, G.; MOREIRA, RENATA; SOMOZA, GUSTAVO; PANDOLFI, MATIAS

GENERAL AND COMPARATIVE ENDOCRINOLOGY

ACADEMIC PRESS INC ELSEVIER SCIENCE

Lugar: Amsterdam; Año: 2017 vol. 252 p. 119 - 129

0016-6480

For many species parental behavior is essential for the survival of the offspring. While the ultimate causesof teleost parental behavior have been widely studied, comparatively little is known about its proximatecauses. The aim of this study was to analyze the yet unexplored, potential dual role of brain and gonadalaromatases, the enzymes responsible for the conversion of androgens to estrogens in the brains andgonads of teleosts, respectively, on the different stages of the maternal care period of the biparental cichlidCichlasoma dimerus, locally known as chanchita. By immunohistochemistry we analyzed the neuraldistribution of brain aromatase and observed it exclusively within the forebrain, including areas involvedin the regulation of parental behavior. We next analyzed the gene expression of brain aromatase in thebrain, and gonadal aromatase in the ovary, of female chanchitas through the parental care period. To furthercharacterize the physiological environment associated to maternal care, we also evaluated sex steroidlevels (17b-estradiol, testosterone and 11-ketotestoterone) and ovarian follicle percentage. The onsetof parental behavior specifically downregulated sex steroids synthesis and the rate of ovarian maturation,as denoted by a more than 10-fold decrease in steroid levels and delayed detection of mature follicles infemales with offspring, compared to females which eggs were removed. Gene expression levels of botharomatases were independent of maternal care at the evaluated time points, even though they variedduring the parental care period.