New approach for reproductive toxicity assessment: chromatoid bodies as a target for methylmercury and polychlorinated biphenyls in prepubertal male rats

Autor(es)

Garcia, M. S. ^{[1, 2]} ; Orcini, W. A. ^[3] ; Peruquetti, R. L. ^{[1, 3, 4]} ; Perobelli, J. E. ^[2]

Afiliação do(s) autor(es)

^[1] Sagrado Coracao Univ, Sch Hlth Sci, Rua Irma Arminda, 10-50 Jd, BR-17011160 Bauru, SP - Brazil

^[2] Univ Fed Sao Paulo, Dept Marine Sci, Expt Toxicol Lab, Campus Baixada Santista, 144 Encruzilhada, BR-11070102 Santos, SP - Brazil

^[3] Sagrado Coracao Univ, Mol Biol & Cytogenet Lab, Rua Irma Arminda, 10-50 Jd, BR-17011160 Bauru, SP - Brazil

^[4] Sagrado Coracao Univ, Off Associate Dean Grad Studies & Res, Rua Irma Arminda, 10-50 Jd, BR-17011160 Bauru, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: REPRODUCTION FERTILITY AND DEVELOPMENT; v. 32, n. 10, p. 914-922, 2020.
• Citações Web of Science: 0

Resumo

This study investigated the reproductive toxicity of methylmercury (MeHg) and Aroclor (Sigma-Aldrich), alone or in combination, following exposure of prepubertal male rats considering the chromatoid body (CB) as a potential target. The CB is an important molecular regulator of mammalian spermatogenesis, primarily during spermatid cytodifferentiation. Male Wistar rats were exposed to MeHg and/or Aroclor, according the following experimental design: control group, which was administered in corn oil (vehicle) only; MeHg-treated group, which was administered 0.5 mg kg(-1) day(-1) MeHg; Aroclor-treated group, which was administered 1mg kg(-1) day(-1) Aroclor; Mix-LD, group which was administered a low-dose mixture of MeHg (0.05 mg kg(-1) day(-1)) and Aroclor (0.1 mg kg(-1) day(-1)); and MixHD group, which was administered a high-dose mixture of MeHg (0.5 mg kg(-1) day(-1)) and Aroclor (1.0 mg kg(-1) day(-1)). MeHg was diluted in distilled water and Aroclor was made up in corn oil (volume 1mL kg(-1)). Rats were administered the different treatments from PND23 to PND53 by gavage. The morphophysiology of CBs was analysed, together with aspects of steroid hormones status and regulation, just after the last treatment on PND53. In addition, the long-term effects on sperm parameters were assessed in adult animals. MeHg exposure increased mouse VASA homologue (MVH) protein levels in seminiferous tubules, possibly affecting the epigenetic status of germ cells. Aroclor produced morphological changes to CB assembly, which may explain the observed morphological defects to the sperm flagellum and the consequent decrease in sperm motility. There were no clear additive or synergistic effects between MeHg and Aroclor when administered in combination. In conclusion, this study demonstrates that MeHg and Aroclor have independent deleterious effects on the developing testis, causing molecular and morphological changes in CBs. To the best of our knowledge, this is the first study to show that CBs are targets for toxic agents. (AU)

• Processo FAPESP: 16/04580-0 - Desvendando o papel de proteínas transitórias na composição molecular de chromatoid bodies de mamíferos: Fibrilarina (proteína nucleolar) e CLOCK/BMAL1 (controle ciclo circadiano)
• Beneficiário: Rita Luiza Peruquetti
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 14/26283-1 - Avaliação de parâmetros reprodutivos de ratos púberes e adultos após exposição pré-puberal a baixas doses de metilmercúrio e aroclor.
• Beneficiário: Ana Priscila Gomes Silva
• Modalidade de apoio: Bolsas no Brasil - Programa Capacitação - Treinamento Técnico
• Processo FAPESP: 13/14477-3 - Exposição pré-puberal a baixas doses de metilmercúrio e aroclor associados: avaliação de parâmetros reprodutivos e endócrinos de ratos púberes e adultos
• Beneficiário: Juliana Elaine Perobelli
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 13/26797-2 - Exposição pré-puberal a baixas doses de metilmercúrio e aroclor associados: avaliação de parâmetros reprodutivos de ratos púberes e adultos
• Beneficiário: Mariana Simões Garcia
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica
• Processo FAPESP: 12/22009-7 - Descrição da distribuição da proteína nucleolar fibrilarina no epitélio seminífero de mamíferos e caracterização do seu papel na manutenção da fisiologia de chromatoid bodies
• Beneficiário: Rita Luiza Peruquetti
• Modalidade de apoio: Auxílio à Pesquisa - Regular