RESUMO
OBJECTIVE: Today, researchers have succeeded in achieving oocyte-like cells through the in vitro differentiation of stem cells. MicroRNAs are key regulators of oocyte development. In this study we decided to evaluate the expression pattern of microRNA-21, microRNA-15a, and microRNA-372 in oocyte-like cells, to determine the maturation stage of oocyte-like cells. METHODS: Human follicular fluid samples were collected and centrifuged, and their cells were divided into 3 groups; day 7 as control group, days 14 and 21. During this period, the cells were evaluated for their morphological appearance and viability by inverted microscopy. RNA isolation was performed and cDNA was reversely transcribed by specific stem-loop RT primers. Real-time RT-PCR was used to detect microRNA expression. RESULTS: The relative expression of microRNA-21 and microRNA-15a on day 21 was significantly down-regulated compared to the control group (day 7), but microRNA-372 did not show a significant difference. Also, on day 14 compared to the control group (day 7), microRNA-21 did not show a significant difference; but microRNA-15a and microRNA-372 were significantly down-regulated. MicroRNA-21 and microRNA-15a on day 21 compared to day 14 revealed down-regulated levels, but microRNA-372 revealed up-regulated levels. CONCLUSIONS: Our results showed significant decreases in the expression of microRNA-21 and microRNA-15a in oocyte-like cells, as well as in oocytes, which may lead to cytoplasmic maturation, germinal vesicle break down and the completion of meiosis Ð. In addition, down-regulation expression of microRNA-372 maybe a confirmation that mesenchymal stem cells have differentiated into germ cells, and these cells were differentiated into oocyte-like cells.
Assuntos
Líquido Folicular , MicroRNAs , Oócitos , Humanos , MicroRNAs/metabolismo , MicroRNAs/genética , Feminino , Oócitos/metabolismo , Líquido Folicular/metabolismo , Líquido Folicular/citologia , Diferenciação Celular , Células-Tronco/metabolismo , Células-Tronco/citologia , Adulto , Células CultivadasRESUMO
It is well known that female reproduction ability decreases during the forth decade of life due to age-related changes in oocyte quality and quantity; although the number of women trying to conceive has today increased remarkably between the ages of 36 to 44. The causes of reproductive aging and physiological aspects of this phenomenon are still elusive. With increase in the women's age, during Assisted Reproductive Technologies (ART) we have perceived a significant decline in the number and quality of retrieved oocytes, as well as in ovarian follicle reserves. This is because of increased aneuploidy due to factors such as spindle apparatus disruption; oxidative stress and mitochondrial damage. The aim of this review paper is to study data on the potential role of the aging process impacting oocyte quality and female reproductive ability. We present the current evidence that show the decreased oocyte quality with age, related to reductions in female reproductive outcome. The aging process is complicated and it is caused by many factors that control cellular and organism life span. Although the factors responsible for reduced oocyte quality remain unknown, the present review focuses on the potential role of ovarian follicle environment, oocyte structure and its organelles. To find a way to optimize oocyte quality and ameliorate clinical outcomes for women with aging-related causes of infertility.
Assuntos
Infertilidade Feminina , Oócitos , Adulto , Envelhecimento , Feminino , Humanos , Folículo Ovariano , ReproduçãoRESUMO
OBJECTIVES: This study evaluated taurine (TAU) effects on autophagy, apoptosis and oxidative stress in mice Leydig TM3 cells. METHODS: We treated TM3 cells with TAU (100 µg/mL) or 3-Methyladenine (3-MA, an autophagy inhibitor) for 24 h, and assessed cell viability, testosterone level, oxidative stress, apoptosis, and autophagy. RESULTS: The results showed that TAU markedly increased cell viability, testosterone levels, expression of autophagy-related genes and percentage of LC3-II-positive cells. TAU significantly reduced malondialdehyde (MDA) contents and reactive oxygen species (ROS) levels and increased the activities of SOD (superoxide dismutase) and CAT (Catalase) enzymes in the TM3 cells. TAU in the presence of autophagy inhibitor (3-MA) increased oxidative stress and decreased testosterone levels. CONCLUSION: The results showed that autophagy might be involved in TAU-increased testosterone levels in mice Leydig TM3 cells.