Interaction of melatonin and gonadotropin-inhibitory hormone on the zebrafish brain-pituitary-reproductive axis

Abstract

Circadian cycles and photoperiod are known to influence reproductive physiology in several animals. Neuropeptides, such as gonadotropin-inhibitory hormone (GNIH) and gonadotropin-releasing hormone (GNRH), are influenced by melatonin in birds and mammals. The present study demonstrates the role of melatonin in oocyte maturation in the zebrafish (Danio rerio), via the brain-pituitary-reproductive axis, under different photic conditions. Melatonin was significantly higher both in the whole brain and ovary under continuous dark (DD) compared to continuous light (LL) conditions. Transcription of gnih in the brain was high in LL, but low in DD; similarly, melatonin exogenous treatment reduced gnih in cultured brain in a dose-dependent manner. Expression of gnrh3, however, was high in both continuous photic conditions (DD and LL), whereas fshb and lhb were high only during DD. kiss2, another neuropeptide, was high in LL, but kiss1 remain unchanged among the conditions. At the gonad level, expression of fshr, lhcgr, mtnr1aa, and mtnr1ab tracked with the expression of their respective ligand in DD and LL. The expression of mprb is high in DD ovary, although intra-ovarian growth factors (tgfb1a and bmp15) were low. The measured increased percentages of germinal vesicle breakdown, expression of Cyclin B1, and reduced Cdc2p34 phosphorylation are consistent with increased maturation in the dark. Our study thus links melatonin to the inhibition of gnih in the brain-pituitary-reproductive axis of zebrafish in response to photic conditions.

Ontogeny of gonadotrophin‐inhibitory hormone in the cichlid fish Cichlasoma dimerus

“…These results provide anatomical evidence supporting a potential role of GnIH as a neuromodulator of photoreception and integration of different sensory modalities not only in adults, but also throughout development. In line with this, GnIH expression levels have been shown to be modulated by photoperiod and melatonin in adults of D. rerio and Amphiprion melanopus . Moreover, Paullada‐Salmeron et al .…”

Research progress on the role of melatonin and its receptors in animal reproduction: A comprehensive review

“…Melatonin and its metabolites act as dominant antioxidants, which can possibly prevent early ovarian miscarriage. From the current literature of background work (Arendt, ; Banach, Gurdziel, Jedrych, & Borowicz, ; De Leersnyder et al., ; Duffield et al., ; El‐Mokadem et al., ; Grossman, Laudon, & Zisapel, ; Henriquez et al., ; Hillier, ; Howard & Lutterschmidt, ; Hu, Christian, Sipes, & Hoyer, ; Jan et al., ; Kang et al., ; Koppisetti et al., ; Li et al., ; Maganhin et al., ; Mukherjee et al., ; Peres, Masruha, Zukerman, Moreira‐Filho, & Cavalheiro, ; Pierce & Parsons, ; Reiter et al., ; Reiter et al., ; Rozen, ; Saenz De Miera et al., ; Sambrook & Russell, ; Sanchez‐Barcelo et al., ; Singh & Haldar, ; Singh & Jadhav, ; Tian et al., ; Ubuka et al., ; Valenzuela, Vera, Venegas, Pino, & Lagunas, ; Vijayalaxmi, Reiter, Herman, & Meltz, , ; Weems, Goodman, & Lehman, ; Yoshimura, ; Yumnamcha et al., ), there has been extensive progress of action mechanism of melatonin and its related areas. For instance, the protection of gametes and embryos (Voiculescu et al., ), the response of clock genes (Saenz De Miera et al., ; Vriend & Reiter, ) and the immune‐neuroendocrine interactions (Vijayalaxmi et al., ) reconcile seasonal variations in immune functions and the silencing or blockage of genes.…”

“…The current investigation of this literature shows that melatonin performs a vigorous action in the pathogenesis of several reproductive practices. Melatonin consistently occurs in animals' pre-ovulation follicular fluid, and the melatonin receptors exist in ovarian GPs, which (Arendt, 1986;Banach, Gurdziel, Jedrych, & Borowicz, 2011;De Leersnyder et al, 2003;Duffield et al, 2002;El-Mokadem et al, 2017;Grossman, Laudon, & Zisapel, 2011;Henriquez et al, 2017;Hillier, 1994;Howard & Lutterschmidt, 2015;Hu, Christian, Sipes, & Hoyer, 2001;Jan et al, 2000;Kang et al, 2009;Koppisetti et al, 2008;Li et al, 2011;Maganhin et al, 2013;Mukherjee et al, 2015;Peres, Masruha, Zukerman, Moreira-Filho, & Cavalheiro, 2006;Pierce & Parsons, 1981;Reiter et al, 2010;Reiter et al, 2014;Rozen, 2003;Saenz De Miera et al, 2014;Sambrook & Russell, 2001;Sanchez-Barcelo et al, 2005;Singh & Haldar, 2007;Singh & Jadhav, 2014;Tian et al, 2017;Ubuka et al, 2012;Valenzuela, Vera, Venegas, Pino, & Lagunas, 2015;Vijayalaxmi, Reiter, Herman, & Meltz, 1996Weems, Goodman, & Lehman, 2015;Yoshimura, 2010;Yumnamcha et al, 2017), there has been extensive progress of action mechanism of melatonin and its related areas. For instance, the protection of gametes and embryos (Voiculescu et al, 2014), the response of clock genes…”

Artificial Light at Night (ALAN): A Potential Anthropogenic Component for the COVID-19 and HCoVs Outbreak

“…The detrimental physiological and behavioral effects resulting from the exposure to light at night are known (2,(8)(9)(10), but the influences of light pollution on the emergence and development of the infectious disease are yet to be elucidated. The appearance Graphical Abstract | Impact of artificial light at night on the physiology and behavior of the nocturnal animal, the bat.…”

“…The detrimental physiological and behavioral effects resulting from the exposure to light at night are known ( 2 , 8 – 10 ), but the influences of light pollution on the emergence and development of the infectious disease are yet to be elucidated. The appearance of new infectious diseases is increasing since the last decade and has posed a significant threat to public health worldwide.…”