Melatonin concentrations in relation to oxidative status and oocyte dynamics in the ovary during different reproductive phases of an annual cycle in carp Catla catla

Melatonin actions on ovaprim (synthetic GnRH and domperidone)-induced oocyte maturation in carp

“…The results of correlation coefficient analysis also depicted a significant positive correlation between the rate of GVBD, density of cyclin B as well as Cdc34 proteins, and the profiles of SOD, CAT, GPx, GRd and GST, but a negative correlation with the level of MDA in the maturing ovarian follicles. Moreover, a significant positive correlation between the concentrations of melatonin and the levels of SOD, CAT, GPx, GRd and GST in the studied ovarian follicles underlines their interplay and physiological significance in reducing oxidative stress (Hasan et al 2014). These findings are complementary to the study on human granulosa cells, where stimulatory effects of melatonin on antioxidative enzymes have been shown to improve the quality of oocytes (Muchová et al 1998).…”

“…The extracted samples were resuspended in 300 ml PBS-gelatin buffer (0.2 mol sodium phosphate/l, 0.15 mol NaCl/l, 0.05% gelatin, 10 mmol EDTA/l and 0.15% NaN 3 ; pH 6.0) and used for the estimation of melatonin concentrations following a specific well-calibrated RIA, using [ 3 H]melatonin (specific activity 84.0 Ci/mmol) as the tracer (100 ml equivalent to about 4000 c.p.m.) and melatonin antiserum (sheep anti-melatonin antibody) at a final dilution of 1:4000 (Hasan et al 2014). The assay was validated by Melatonin and ovaprim actions on carp oocytes both parallelism and recovery tests.…”

“…Each assay was validated by serial dilutions of the substrates and/or addition of selective inhibitors of respective enzymes (Hasan et al 2014).…”

“…The information gathered from mammalian studies also reveals that melatonin acts on various cells of ovarian follicles as an indirect antioxidant to stimulate several antioxidative agents, such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione transferase (GST) and reduced glutathione (GSH), which metabolize free radicals to reduce oxidative stress (Reiter 1996). In the absence of comparable data from any fish study, a recent finding on carp provides the first indication that intra-ovarian melatonin might be implicated in the reduction of oxidative stress to augment ovarian functions during spawning (Hasan et al 2014). In such study, a significant positive correlation between the concentrations of melatonin and the levels of different antioxidative agents (SOD, CAT and GST) in the ovary is noted throughout the annual reproductive cycle.…”

Towards a physiological response of fishes under variable environmental conditions: An approach through neural network

“…Besides, various agricultural and industrial waste materials enter estuarine environment and being taken up by aquatic organisms induce critical physiological changes. Some pollutants may directly enhance ROS formation whereas others may act indirectly by binding with cellular thiols and reducing antioxidant potential (Hasan et al, 2014). Different aquatic organism exhibit differential levels of vulnerability against environmental toxicants and a wide spectrum of inter-site differences in stress response of same organism have been observed (Stoliar and Lushchak, 2012).…”