Implicating transforming growth factor-β and sex steroids in the regulation of brain-gonadal functions

Transforming growth factor-beta (Tgf-β) significantly mediates TGF signals in the brain and gonadal development. The present study insights into the implication of novel factor Tgf-β and sex steroids in coordination with catecholaminergic activity; moreover, the influence on catecholamines, gonadotropin-releasing hormone (GnRH1), and related transcripts/genes by implanting osmotic pump-mediated mismatches sex steroids in the teleost. The outcome collectively showed the severe effect of estrogenic compounds at the nominal dose over androgenic to alter reproductive conditions. In addition, the differential pattern of key transcription factors/genes revealed significantly higher expression in the brain and gonads than in other organs, which seem to have a role in the hypothalamic-pituitary-gonadal (H-P-G) axis to regulate brain-gonadal functions in catfish. Furthermore, the abundance of crucial factors mRNA and protein expression in the brain suggests a significant role in this correlation. Collectively, the study provides an understanding of the growth factors and sex steroids through dopaminergic system, where upregulated expression levels of GnRH1 vis-a-vis certain brain-related genes, that is, GnRH1, Tgf-β, Gfrα-1, cyp19a1b, tph, and th in teleost revealed their regulatory influence more importantly on the H-P-G axis.