title: Impairment of the immune system in GH-overexpressing transgenic zebrafish (Danio rerio).
abstract: Growth hormone (GH) is an important regulator of immune functions in vertebrates, and it has been intensively reported a series of stimulatory actions of this hormone over on the immune system. Within aquaculture, overexpression of GH has been considered a promising alternative for promoting higher growth rates in organisms of commercial interest. Considering the various pleiotropic effects of GH, there are still few studies that aim to understand the consequences of the excess of GH on the physiological systems. In this context, our goal was to present the effects of the overexpression of GH on immune parameters using a model of zebrafish (Danio rerio) that overexpress this hormone. The results showed that GH transgenic zebrafish had 100% of mortality when immunosuppressed with dexamethasone, revealing a prior weakening of the immune system in this lineage. Morphometric analysis of thymus and head kidney revealed a reduction in the area of these structures in transgenic zebrafish. Moreover, the phenotypic expression of CD3 and CD4 thymocytes was also depreciated in transgenic zebrafish. Furthermore, a decrease was noted in the expression of genes RAG-1 (60%), IKAROS (50%), IL-1β (55%), CD4 (60%) and CD247 (40%), indicating that development parameters, of innate and acquired immunity, are being harmed. Based on these results, it can be concluded that the excess of GH impairs the immune functions in GH transgenic zebrafish, indicating that the maintenance of normal levels of this hormone is essential for the functioning of immunological activities.
authors.affiliation: Programa de Pós-Graduação em Ciências Fisiológicas, Fisiologia Animal Comparada, Universidade Federal do Rio Grande-FURG, Avenida Itália, Km 8, CEP 96201-900 Rio Grande, RS, Brazil; Instituto de Ciências Biológicas, Universidade Federal do Rio Grande-FURG, Avenida Itália, Km 8, CEP 96201-900 Rio Grande, RS, Brazil.
authors.forename: Carolina R
authors.initials: CR
authors.lastname: Batista
authors.affiliation: Programa de Pós-Graduação em Aquicultura, Universidade Federal do Rio Grande-FURG, Avenida Itália, Km 8, CEP 96201-900 Rio Grande, RS, Brazil; Instituto de Ciências Biológicas, Universidade Federal do Rio Grande-FURG, Avenida Itália, Km 8, CEP 96201-900 Rio Grande, RS, Brazil.
authors.forename: Márcio A
authors.initials: MA
authors.lastname: Figueiredo
authors.affiliation: Programa de Pós-Graduação em Ciências Fisiológicas, Fisiologia Animal Comparada, Universidade Federal do Rio Grande-FURG, Avenida Itália, Km 8, CEP 96201-900 Rio Grande, RS, Brazil; Instituto de Ciências Biológicas, Universidade Federal do Rio Grande-FURG, Avenida Itália, Km 8, CEP 96201-900 Rio Grande, RS, Brazil.
authors.forename: Daniela V
authors.initials: DV
authors.lastname: Almeida
authors.affiliation: Programa de Pós-Graduação em Aquicultura, Universidade Federal do Rio Grande-FURG, Avenida Itália, Km 8, CEP 96201-900 Rio Grande, RS, Brazil; Instituto de Oceanografia, Universidade Federal do Rio Grande-FURG, Avenida Itália, Km 8, CEP 96201-900 Rio Grande, RS, Brazil.
authors.forename: Luis A
authors.initials: LA
authors.lastname: Romano
authors.affiliation: Programa de Pós-Graduação em Ciências Fisiológicas, Fisiologia Animal Comparada, Universidade Federal do Rio Grande-FURG, Avenida Itália, Km 8, CEP 96201-900 Rio Grande, RS, Brazil; Programa de Pós-Graduação em Aquicultura, Universidade Federal do Rio Grande-FURG, Avenida Itália, Km 8, CEP 96201-900 Rio Grande, RS, Brazil; Instituto de Ciências Biológicas, Universidade Federal do Rio Grande-FURG, Avenida Itália, Km 8, CEP 96201-900 Rio Grande, RS, Brazil. Electronic address: dqmluf@furg.br.
authors.forename: Luis F
authors.initials: LF
authors.lastname: Marins
mesh_terms: D056704:Adaptive Immunity; D000818:Animals; D030801:Animals, Genetically Modified / Q000235:genetics / Q000378:metabolism; D005786:Gene Expression Regulation; D013006:Growth Hormone / Q000235:genetics* / Q000378:metabolism; D060226:Head Kidney / Q000254:growth & development / Q000378:metabolism; D007107:Immune System / Q000503:physiopathology*; D007113:Immunity, Innate; D007150:Immunohistochemistry / Q000662:veterinary; D013950:Thymus Gland / Q000254:growth & development / Q000378:metabolism; D015027:Zebrafish / Q000235:genetics* / Q000254:growth & development / Q000276:immunology*
chemical_list: D013006:Growth Hormone
keywords: Gene expression; Head kidney; Immunity; Immunohistochemistry; Thymus