Effect of Antioxidants ( β -mercaptoethanol and Cysteamine) on Assisted Reproductive Technology In vitro

Abstract

IntrOductIOnIVM of oocytes is an effective method for the production of mature oocyte used in ART, which includes IVF cloning and Intra Cytoplasmic Sperm Injection (ICSI). IVM is a cost-benefit technique with few side effects for gonadotropin stimulation of IVF, and is a simple treatment for certain infertile couple [1][2][3][4]. The GV-stage oocytes which are stripped of cumulus cells have a reduced developmental capacity when compared with cumulus enclosed GV-stage oocytes [5,6]. Cumulus cells play an important role in oocyte maturation, since they provide and transfer several known and unknown factors that are essential in the regulation of meiotic progression, normal nuclear and cytoplasmic maturation of oocytes and subsequent embryonic development after fertilization [7,8]. Studies have demonstrated that inappropriate culture mediums increase ROS resulting in OS events, DNA damage and low quality of oocytes. These are the main factors that lead to failure in IVM and decrease productivity [9,10]. OS appears to be responsible for many injuries in the embryo and oocyte [9,11,12]. Embryo metabolism generates ROS via several enzymatic mechanisms that penetrate the cell membrane and pass through it to damage cellular molecules such as lipids, proteins, and nucleic acids [13]. BME and CYS are thiol compounds that stimulate glutathione (GSH) synthesis [14]. Despite the fact that there is more stability of CYS than other thiol compounds, the effect of this substance on the growth of oocytes or embryos depending on breed, dose rate and the medium, is shown differently.GSH is one of the components of many biological processes, which includes the construction of DNA, protein metabolism of drugs and chemicals, and it protects the cells during OS events [15]. In addition, GSH and its revival mode of reproduction and early development of organism play a unique role. It can reduce the generation of free radicals such as hydrogen peroxide and oxygen free radicals, which are disruptive to oocytes. It has been shown that GSH plays an important role in oocyte maturation [15]. Intracellular GSH is an essential part in the development of the oocyte cytoplasm. Activities of GSH-related antioxidant properties protect the oocyte at the front of the active molecules of oxygen is toxic. With this consideration, this study was designed to evaluate the effects of antioxidants (BME and CYS) on improving ART invitro which is essential. Therefore, the main purpose of this study was to ascertain whether enriching the oocyte medium with antioxidants, BME and CYS may improve IVM and fertilization and embryo development into blastocyst, of mouse immature oocyte. MAterIAls And MethOdsThis experimental study was carried out in the cellular and molecular research center at Yasuj University of Medical Sciences in Iran. The University ethic committee approved the design of study. Sixteen mice were housed under standard laboratory conditions (temperature of 20±2°C, relative humidity of 40-45% and light-dark cycle of 12:12 hour) and had free access ...

Effects of Supplementation with Natural Antioxidants on Oocytes and Preimplantation Embryos

“…GSH plays central roles in oocyte maturation and in protecting them from damages reactive oxygen species-induced [80]. In a mouse model, in vitro maturation (IVM) of immature oocytes and IVF outcome resulted favored by the concomitant supplementation of 100 µM β-mercaptoethanol and cysteamine in culture media [80]. These findings are in line with the results obtained using a bovine in vitro system [81].…”

“…β-mercaptoethanol and cysteamine are thiol compounds that stimulate GSH synthesis. GSH plays central roles in oocyte maturation and in protecting them from damages reactive oxygen species-induced [ 80 ]. In a mouse model, in vitro maturation (IVM) of immature oocytes and IVF outcome resulted favored by the concomitant supplementation of 100 µM β-mercaptoethanol and cysteamine in culture media [ 80 ].…”

Procyanidin B1 promotes in vitro maturation of pig oocytes by reducing oxidative stress

“…The positive effects of antioxidants on IVM and embryo development has been widely reported, such as the quality of porcine blastocysts during in vitro embryonic development can be markedly improved by the addition of β‐mercaptoethanol (BME) and l ‐ascorbic acid (AC) (Castillo‐Martin et al, 2014). The rate of IVM and oocyte evolution, and murine embryo formation could be significantly increased by the addition of BME and cysteamine (CYS）（Nikseresht et al, 2017). Moreover, the combination of resveratrol and melatonin supported a synergistic increase in oocyte nuclear maturation and total cell numbers of PA blastocysts and improved the development of somatic cell nuclear transfer (SCNT) embryos (Lee et al, 2018).…”

DMSO supplementation during in vitro maturation of bovine oocytes improves blastocyst rate and quality

“…However, previous reports showed that over 1% DMSO has cellular toxic effect through alterations in the structure of plasma membrane, cytoplasm [29,30], extrusion of 1PB [29], dysregulated gene expression and apoptosis [7]. In turn, blastocyst rate in 1% DMSO was similar to control group and it showed a quadratic response with an optimum at 0.45% v:v. This response is probably due a long-term effect of maturation on oocyte developmental since part of oocyte competence is acquired during this complex and dynamic process [32,33,34,35,36,37,38,39]. On the other hand, when similar doses of DMSO were used for a longer period, during the in vitro culture, effect on blastocyst rates was not observed [40,6].…”