Title of article :
Orexin A promotes granulosa cell secretion of progesterone in sheep
Author/Authors :
Li ، M. - The Inner Mongolia Agricultural University , Li ، M. - The Inner Mongolia Agricultural University , Zu ، N. - The Inner Mongolia Agricultural University , Zu ، N. - The Inner Mongolia Agricultural University , Zhang ، C. S. - The Inner Mongolia Agricultural University , Zhang ، C. S. - The Inner Mongolia Agricultural University , Xie ، M. Y. - The Inner Mongolia Agricultural University , Xie ، M. Y. - The Inner Mongolia Agricultural University , Liu ، Y. Z. Agriculture and Animal Husbandry Department of Inner Mongolia Autonomous Region , Liu ، Y. Z. Agriculture and Animal Husbandry Department of Inner Mongolia Autonomous Region , Xu ، X. J. - The Inner Mongolia Agricultural University , Xu ، X. J. - The Inner Mongolia Agricultural University
Abstract :
Background: Orexin A, a smallmolecule peptide, can regulate female hormones, but limited evidence for its mechanism of activity exists in ovine. Aims: The objective of this study was to investigate the effect of orexin A on progesterone (P4) secretion in cultured granulosa of sheep follicles. Methods: Sheep ovarian granulosa were isolated and identified, preincubated with luteinizing hormone (LH) (2.5 IU/ml), folliclestimulating hormone (FSH) (2.5 IU/ml), or oestrogen (1 µg/ml); and cultured in vitro. The pretreated sheep ovarian granulosa were subsequently cultured with different concentrations (1 nM, 10 nM, 58 nM, 100 nM, and 145 nM) of orexin A for varying amounts of time (0 h, 24 h, 48 h, and 72 h). Then, the expression levels of P4, steroidogenic acute regulatory protein (StAR), 3βHydroxysteroid dehydrogenase (3βHSD) and cytochrome P450 (CYP11) were determined. Results: The results showed that the sheep ovarian granulosa were correctly identified. The different concentrations of orexin A promoted the secretion of P4 from granulosa in the ovine ovary compared with that in the control. The expression of StAR, 3βHSD and P450 (CYP11) gradually increased, and then decreased with increasing concentrations of orexin A, but the expression of P450 (CYP11) decreased with the increase of time. Conclusion: These results revealed that orexin A promotes the secretion of P4 by regulating the expression of StAR, 3βHSD, and P450 (CYP11). Understanding the mechanism underlying the promotion of P4 by orexin A could open new therapeutic possibilities in the treatment of hormone homeostasis.
Keywords :
P450 (CYP11) , Progesterone , Orexin A , StAR
Journal title :
Iranian Journal of Veterinary Research (IJVR)
Journal title :
Iranian Journal of Veterinary Research (IJVR)
