Insulin-like growth factors 1 and 2 are associated with testicular germ cell proliferation and apoptosis during fish reproduction.
Reprod Fertil Dev
; 32(11): 988-998, 2020 Jul.
Article
em En
| MEDLINE
| ID: mdl-32693911
ABSTRACT
To support sperm production, fish testes undergo intense tissue remodelling, with endocrine, paracrine and autocrine signals regulating gonad physiology. The aim of this study was to investigate the testicular expression of insulin-like growth factor (Igf) 1 and Igf2 during spermatogenesis, and their relationship with cell proliferation and apoptosis throughout the reproductive cycle. The study was performed in male Hypostomus garmani, a catfish living in headwater rivers of the São Francisco River basin, Brazil. Spermatogenesis was analysed using histology, morphometry, immunohistochemistry and terminal deoxyribonucleotidyl transferase-mediated dUTP-digoxigenin nick end-labelling (TUNEL) analysis at different maturity stages. The results showed the proliferation of spermatogonia throughout the reproductive cycle, with a higher rate during the ripe stage. Germ and Sertoli cells expressed Igf1 at all stages of testicular maturity, Igf2 was predominant at the ripe stage and both Igf1 and Igf2 occurred at the spent stage. Caspase-3 and TUNEL analysis revealed a higher rate of apoptosis at the spent stage associated with reduced expression of Igf1 and Igf2. Sertoli cell proliferation was associated with spermatogonia and spermatocyte cysts at different stages of the reproductive cycle. Together, the data support a proliferative role for Igf1 and Igf2 in regulating testicular apoptosis in H. garmani, with cyclical variation in their expression during gonad maturation.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Espermatogênese
/
Espermatogônias
/
Peixes-Gato
/
Fator de Crescimento Insulin-Like I
/
Fator de Crescimento Insulin-Like II
/
Apoptose
/
Proliferação de Células
Tipo de estudo:
Risk_factors_studies
Limite:
Animals
Idioma:
En
Ano de publicação:
2020
Tipo de documento:
Article