Mahammed Moniruzzaman
University of Calcutta, India
Title: Pre-treatment of phytochemical (Tribulus extract) alleviates intra-follicular oxidative stress and ameliorates oocyte maturation in catfish
Biography
Biography: Mahammed Moniruzzaman
Abstract
Present communication is an attempt to demonstrate the influence of phytochemicals on the action of maturation inducing hormone (MIH) on the maturation of oocytes. The oocytes from gravid female catfish Mystus dibrugarensis were isolated and incubated separately in Medium (a) MIH (1 µg/ml), (b) ethanolic extract of Tribulus, (c) Aqueous extract of Tribulus (d) MIH administered with (i) ethanolic extract of Tribulus, (ii) Aqueous extract of Tribulus and the effects of treatment on oocyte maturation were evaluated by considering the rate (%) of germinal vesicle breakdown (GVBD). Incubation of oocytes in medium containing only Tribulus extract (both aqueous and ethanolic) did not result in any significant change in GVBD percentage. Nearly all the oocytes underwent GVBD when incubated with MIH for around 20h. However, it was quite interesting to observe that incubation of oocytes with Tribulus extract co-administered with MIH in the medium, led to an accelerated rate of GVBD in the oocytes. Further study revealed that incubation with Tribulus extract accelerates the action of MIH on the formation of a complex of two proteins (MPF), a regulatory component called cyclin B and the catalytic component protein kinase known as cyclin-dependent kinase, Cdk1. Notably, administration of Tribulus extract, led to a sharp reduction in the follicular level of MDA (malondialdehyde) - an intra-cellular stress marker, and significant increase in the activity/level of both enzymatic [SOD (superoxide dismutase), CAT (catalase), GST (glutathione transferase), GPx (glutathione peroxidase) and GRd (glutathione reductase)] and non-enzymatic [GSH (reduced glutathione)] antioxidants. Collectively, current study presents the evidence of phytochemical administration in the incubation medium alleviates oxidative stress of pre-ovulatory follicles by stimulating different antioxidants and ameliorates MIH actions on the process of final oocyte maturation through formation of MPF