Inhibin anti-peptide antibody macromolecule: An approach to improve fecundity in Clarias batrachus

Inhibins are members of the transforming growth factor beta (TGFβ) superfamily known to regulate ovarian functions through stimulation of the hypothalamo-pituitary-gonadal axis. In the present study, we aimed to design a species-specific inhibin-α chimeric peptide (ICP) and evaluate the effect of immunoneutralization using anti-ICP antisera to enhance the reproductive performance in female Clarias batrachus. Injection of anti-ICP antisera caused a significant increase in the number of oocytes at a medium dose (200 μl) in comparison to high dose (400 μl) and control (normal rabbit serum). Histological observations confirmed the dose-dependent advancement in oocyte maturation. Furthermore, anti-ICP antisera treated groups exhibited a significant increase in the serum concentrations of follicle stimulating hormone (FSH) and 17β-estradiol (E2) hormones. The anti-ICP antisera decreased the mRNA expression levels of inhibin-α while stimulated the transcript levels of inhibin-βA, FSHβ, CYP 19a1, 3β-HSD and StAR respectively in a dose-dependent manner. Collectively, these findings indicate that anti-ICP antibody macromolecules modulate the endogenous reproductive hormonal secretion and enhance oocyte quality and quantity in female C. batrachus. This is the first report wherein antibodies against inhibins were used to promote reproductive performances and investigate the underlying molecular mechanisms in fishes.