Delayed ovulation and delayed fertilization can lead to reduced developmental competence of the oocyte. In contrast to the consequences of postovulatory aging of the oocyte, hardly anything is known about the molecular processes occurring during oocyte maturation if ovulation is delayed (preovulatory aging). We investigated several aspects of oocyte maturation in two models of preovulatory agin...

Hydrogen sulfide (H2S) has been revealed to be a signal molecule with second messenger action in the somatic cells of many tissues, including the reproductive tract. The aim of this study was to address how exogenous H2S acts on the meiotic maturation of porcine oocytes, including key maturation factors such as MPF and MAPK, and cumulus expansion intensity of cumulus-oocyte complexes. We observ...

Although oocytes of many teleost fish, especially marine species, are subjected to a hydration process during meiotic maturation, which leads to an important volume increase, no noticeable hydration of the preovulatory oocyte has ever been reported in rainbow trout (Oncorhynchus mykiss). In the present study, oocyte water content and dry mass were monitored using consecutive samples taken in vi...

The serpin peptidase inhibitor, clade E, member 2 (SERPINE2) inhibits urokinase-type plasminogen activator (PLAU) and tissue-type plasminogen activator. Higher SERPINE2 expression levels were detected in cumulus cells of human immature oocytes than in those of mature oocytes. The objective of this study was to evaluate whether high SERPINE2 levels in cumulus cells are associated with oocyte imm...

background:   objective: the aim of this study was to evaluate the in vitro developmental competence of mouse vitrified pre-antral follicles in comparison to isolated pre-antral follicles derived from vitrified ovaries in the presence of alpha lipoic acid (ala).   materials and methods: pre-antral follicles derived from fresh, vitrified-warmed ovarian tissues and vitrified–warmed pre-antral fol...

background: repeated in vitro fertilization (ivf) failure together with ovarian hyperstimulation syndrome (ohss) is one of the distressing situations leading couples to search for alternative treatment options. for such patients with polycystic ovarian syndrome (pcos) who have experienced ovarian hyperstimulation syndrome, mild ovarian stimulation with in vitro oocyte maturation could be a prom...

background: leukemia inhibitory factor (lif) is a 45-56 kda glycoprotein that has an important role in proliferation and embryo implantation. its effect on oocyte maturation and how to exert the function remained to be elucidated. methods: immature mice superovulated with human menopausal gonadotropin and germinal vesicle (gv) oocytes were obtained from ovary 48 hours after. gv oocytes were cul...

abstract: introduction & objective: the infertility treatment by using in vitro matured oocyte has many potential applications. it minimizes the risk of ovarian hyper stimulation and is an alternative treatment for women with polycystic ovarian syndrome who may have problems regarding stimulation for ivf. this method may prove important for subjects in need of fertility preservation and also pr...

The present study examined the kinetics of glutathione (GSH) concentration during maturation and after fertilization in pig oocytes and its relevance to the ability of pig oocytes to form a male pronucleus after in vitro fertilization. The GSH concentration was significantly higher in pig oocytes matured in Waymouth medium than in pig oocytes matured in either modified (m) TCM-199 or mTLP media...

4 Introduction 4 A. Zebrafish as a Model Organism for Developmental Biology 4 B. Processes of Oocyte Maturation in Zebrafish 5 C. Wnt Signaling Pathways and Their Possible Role in Oocyte Maturation 11 D. Preliminary Findings and Objectives of This Research Project 15 Materials and Methods 16 A. Overview 16 B. Oocyte Harvesting and in vitro Maturation 17 C. RNA Extraction and cDNA Conversion 18 ...