جستجوی مقالات مرتبط با کلیدواژه « Ovarian Follicles » در نشریات گروه « پزشکی »

Lysophosphatidic acid (LPA) contributes to follicular activation, oocyte maturation, in vitro fertilization, and embryo implantation.

This study was designed to evaluate the effects of LPA to improve the development of isolated follicles derived from whole mouse cultured vitrified ovaries.

In this experimental study, first, the 1-wk-old mouse ovaries in the non-vitrified and vitrified groups were cultured in the presence of 20 µM of LPA for 1 wk. Then, their isolated preantral follicles were cultured individually for 12 days in the presence or absence of 40 µM of LPA. The following evaluations were done for the cultured follicles: a viability test using Calcein AM staining, flow cytometry using annexin V/Pi, and analysis of the expression of genes by real-time reverse transcription polymerase chain reaction. The maturation rates of the oocytes were compared among groups and some of the released metaphase II oocytes were subjected to in vitro fertilization.

In all LPA treated groups, the rates of survival and follicular development were higher, and the incidence of cell death and expression of pro-apoptotic genes were lower, than in the non-LPA supplemented groups (p = 0.035). There was no significant difference between the vitrified and non-vitrified groups regarding follicular or oocyte development, but the expression of Bad and LPA receptors genes was significantly altered in the vitrified LPA supplemented group in comparison with the non-vitrified LPA supplemented group (p = 0.028).

LPA improved the survival and developmental potential of the isolated follicles. Despite some alterations in the expression of apoptosis-related genes in the vitrified ovaries, LPA had positive effects on the survival and development of these follicles.

Polycystic ovary syndrome (PCOS) is an endocrine system disruption that affects 6-10% of women. Some studies have reported the effect of Vitex agnus-castus (Vitagnus) on the hypothalamic-pituitary-gonad axis (HPG). This study was conducted to investigate Vitagnus effect on the expression of kisspeptin gene in a rat model of PCOS.
Thirty-two female rats were distributed into: control, Vitagnus-treatment (365 mg/kg for 30 days), PCOS (Letrozole for 28 days) and PCOS animals treated with Vitagnus (30 days of Vitagnus after PCOS induction). At the end of the treatments, serum and ovaries were collected for analysis. Expression level of KISS-1 gene in the hypothalamus was investigated, using Real-Time-PCR.
In the PCOS group compared to control, FSH, progesterone and estradiol levels were decreased, whereas testosterone and LH levels were significantly increased. No significant changes were observed in the Vitagnus-treated animals in compare to control.  However, Vitagnus treatment in the PCOS group, resulted in a raise in progesterone, estrogen and FSH levels and a reduction in the levels of testosterone and LH. Quantitative gene expression analysis showed that PCOS induction resulted in over-expression of KISS-1 gene, however, Vitagnus treatment reduced this up-regulated expression to normal level.
In conclusion, our results indicated that Vitagnus extract inhibited downregulation of KISS-1 gene in the hypothalamus of PCOS rats. Because of the master role of kisspeptin in adjusting the HPG axis, Vitagnus is likely to show beneficial effects in the treatment of PCOS via regulation of kisspeptin expression. This finding indicates a new aspect of Vitagnus effect and may be considered in its clinical applications.

Vitrification of the ovarian tissue is one of the techniques recommended for preserving the fertility of women who are dealing with infertility. Despite its benefits, our information about the molecular aspects of ovarian follicles vitrification is somehow ambiguous. Therefore, the aim of this study was to evaluate the expression pattern of DNA repair genes in vitrified preantral follicles.

In this experimental study, the isolated preantral follicles (n=906) from 14-16 days old mice (n=12) were divided into three groups: fresh, toxic and vitrified which were cultured in vitro for 12 days. Preantral follicles were vitrified using cryotop followed by exposure to equilibration solution for five minutes and vitrification solution (VS) for 30 seconds. In the toxic group, preantral follicles were only placed in equilibration and vitrification media and they were then placed in the warming solutions without exposure to liquid nitrogen. On the second and sixth days of the culture period, real-time quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was carried out to evaluate expression of the selected genes involved in DNA repair, including Msh6 (MutS homolog 6), Mre11 (Meiotic recombination 11), Brca1 (Breast cancer type 1), Rad51 (RAD51 recombinase), Pcna (Proliferating cell nuclear antigen) and Atm (ATM serine/threonine kinase). In addition, developmental parameters including growth, survival rate, antrum cavity formation and ovulation were analyzed.

The relative mRNA expression of Msh6, Mre11, Brca1, Rad51, Pcna and Atm on the second and sixth days of the culture period in vitrified group was significantly higher than those of the control and toxic groups, but there was no significant difference between the toxic and control groups. In addition, developmental parameters of follicles were similar in both toxic and control groups, while both were significantly higher than that of vitrified group.

Vitrification changes the expression pattern of DNA repair genes of the mouse preantral follicles

The unfavorable effects of electromagnetic radiation (EMR) emitted by the cell phone on reproduction health are controversial. Metalloproteinases play a vital role in ovarian follicle development. This study was designed to investigate the effects of exposure to the cell phone on the gelatinolytic activity of in vitro cultured mouse pre-antral follicle.

In this experimental study, pre-antral follicles were isolated from ovaries of immature mice (n=16) and cultured with or without exposure to the cell phone in talking mode for 60 minutes. The gelatinolytic activity was evaluated through the zymography method, as well as the gene expression of matrix metalloproteinases (MMPs) namely MMP-2 and -9 and tissue inhibitors of metalloproteinases (TIMPs) namely, TIMP-1 and -2 by the real-time polymerase chain reaction (PCR) method. Also, in parallel, the development of pre-antral follicles was assessed.

The maturation parameters of the cell phone-exposed pre-antral follicles were significantly lower compared with the control group (P<0.05). The gelatinolytic activity was significantly decreased in the cell phone-exposed preantral follicles compared with the control group (P<0.05). The relative mRNA expression of the MMP-2 gene was significantly (P<0.05) increased in the cell phone-exposed pre-antral follicles whereas the expression rate of the MMP-9 gene was considerably (P<0.05) reduced when compared with the control group. Conversely, the relative expression of the TIMP-1 was markedly (P<0.05) increased in the cell phone-exposed pre-antral follicles while the expression of the TIMP-2 was (P<0.05) significantly diminished in comparison with the control group.

Exposure to the cell phone alters the growth and maturation rate of murine ovarian follicle through the changing in the expression of the MMP-2 and -9 genes, as well as the gelatinolytic activity.

 Letrozole, as an aromatase inhibitor drug, is administrated to induce ovulation in individuals with anovulation disorder and, at the same time, it is used to enhance pregnancy success. The current study was designed to investigate the effect of Letrozole on follicular growth/atresia, as well as uterine histology. For this purpose, 15 mature female NMRI mice were assigned into 3 groups (NO=5 in each group): Control, Control sham, which received double distilled water, orally and experimental group received 0.5 mg/kg letrozole, orally.

  Following 14 days, the animals were euthanized and, the follicular number and percentage of atresia at different stages of growth and the morphometric changes of uterine tissue were analyzed and compared between groups.

  The animals in experimental group represented no significant changes in primary, secondary, tertiary follicles, but exhibited a remarkable (p<0.05) reduction in graafian follicles number per two ovaries versus control and control-sham animals. Moreover, the letrozole -received mice exhibited diminished percentages of graafian follicles compared to control and control-sham animals. Finally, the endometrial thickness, as well as endometrial glands distribution per one mm2 of tissue were decreased in experimental group when compared to control and control-sham animals.

Letrozole significantly reduces the graafian  follicles atresia and via this mechanism up-regulates the ovulation ratio. However, it is able to prolong uterine development during a menstrual cycle.

This study was designed to evaluate the effects of vitrification and in vitro culture of human ovarian tissue on the expression of oocytic and follicular cell-related genes.
In this experimental study, ovarian tissue samples were obtained from eight transsexual women. Samples were cut into small fragments and were then assigned to vitrified and non-vitrified groups. In each group, some tissue fragments were divided into un-cultured and cultured (in α-MEM medium for 2 weeks) subgroups. The normality of follicles was assessed by morphological observation under a light microscope using hematoxylin and eosin (H&E) staining. Expression levels of factor in the germ line alpha (FIGLA), KIT ligand (KL), growth differentiation factor 9 (GDF-9) and follicle stimulating hormone receptor (FSHR) genes were quantified in both groups by real-time reverse transcriptase polymerase chain reaction (RT-PCR) at the beginning and the end of culture.
The percentage of normal follicles was similar between non-cultured vitrified and non-vitrified groups (P>0.05), however, cultured tissues had significantly fewer normal follicles than non-cultured tissues in both vitrified and non-vitrified groups (P Human ovarian vitrification following in vitro culture has no impairing effects on follicle normality and development and expression of related-genes. However, in vitro culture condition has deleterious effects on normality of follicles.

The mammalian ovary is controlled by a number of biological rhythms, which regulate the recruitment and release of mature oocytes. The main objective of this study was to investigate the role of cellular clock proteins during follicle maturation in the mouse estrous ovary.
Immunohistochemical (IHC) studies were performed on ovaries from 50 estrous staged mice culled at two time points of 09:00 [day] and 01:00 [mid-point of the dark cycle]. Six antibodies were used to identify the expression of core cellular clock proteins (BMAL1, CLOCK, CRY1, CRY2, PER1 and PER2) within the ovary and four follicle stages, primordial, primary, antral and corpus lutea. IHC data was scored using the Allred protocol and significance determined by Mann-Whitney tests. Differences were considered significant at p All four follicle stages presented greater BMAL1 and CLOCK protein scores during the day and up regulation of CRY1-2 and PER1-2 at night. In primordial follicles, BMAL1 and CLOCK increases were significant (p The ovary demonstrated a cellular clock response to the light: dark cycle and in addition, as the ovarian follicles mature changes in the positive and negative arms of both clock responsive proteins were observed.

The predictive roles of follicle stimulating hormone (FSH), anti-mullerian hormone (AMH) and antral follicle count (AFC) as ovarian reserve markers in women with different age groups are not established well.

This study compares the value of FSH, AMH and AFC at the time of in vitro fertilization (IVF) treatment in different age groups.

In this cross-sectional study, 103 women aged 20-43 years candidates for IVF/ICSI cycle were recruited. FSH, AMH and AFC on day 3 of menstrual cycle were measured. The relationship of these measured markers with outcome variables (oocytes number, number of frozen/fresh embryo and chemical and clinical pregnancy) was assessed in different age groups (i.e. 20-32, 33-37 and 38-43 years).

our results show that age was correlated with clinical pregnancy, oocyte count and fresh and frozen embryo (p

We concluded that the age is the superior predictor of IVF outcome and AMH and AFC are variable predicting markers of ovarian reserve in different age groups.

The measurement of follicular output rate (FORT) has been proposed as a good indicator for evaluating follicular response to the exogenous recombinant folliclestimulating hormone (rFSH). This places FORT as a promising qualitative marker for ovarian function. The objective of the study was to determine FORT as a predictor of oocyte competence, embryo quality and clinical pregnancy after intracytoplasmic sperm injection (ICSI).
This prospective study was carried out on a group of infertile females (n=282) at Islamabad Clinic Serving Infertile Couples, Islamabad, Pakistan, from June 2010 till August 2013. Down- regulated females were stimulated in injection gonadotropins and on ovulation induction day, pre-ovulatory follicle count (PFC) was determined using transvaginal ultrasound scan (TVUS), and FORT was determined as a ratio of PFC to antral follicle count (AFC)×100. Group I consisted of females with a negative pregnancy test, while group II had a positive pregnancy test that was confirmed with the appearance of fetal cardiac activity. Linear regression analyses of categorical variables of clinical pregnancy along with other independent variables, including FORT, were performed using SPSS version 15.0.
Pregnancy occurred in 101/282 women who were tested, recording a clinical pregnancy rate of about 35.8%. FORT values were higher in group II as compared to group I females (P=0.0001). In multiple regression analysis, 97.7, 87.1, 78.2, and 83.4% variations were explained based on the number of retrieved oocytes per patients, number of metaphase II oocytes retrieved, number of fertilized oocytes, and number of cleaved embryos, respectively, indicating FORT as an independent predictor.
FORT is a predictor of oocyte competence in terms of a number of retrieved, mature and fertilized oocytes. It also gives information about the number of cleaved embryos and clinical pregnancy rate.

Anticancer drugs are known to have great impact on spermatogenesis process and germinal epithelium. The present study is to investigate the preventive effect of Cetrorelix (GnRH antagonist) on Cyclophosphamide- induced spermatogenic defect.

Methods and Materials: 

Fifty adult female mice aging 6-8 weeks (30±4 gr) were divided into 3 groups as: Control, Experimental 1 and Experimental 2. The animals in Experimental 1 group received Cyclophosphamide (2.5 mg/kg, ip) for 5 days and in Experimental 2 group received Cetrorelix (0.25 mg/kg, ip) one week before Cyclophosphamide treatment and continued for 3 weeks. The mice in all groups were sacrificed 35 days after the last injection. Ovarian follicles were isolated mechanically and the viability was studied by trypan blue staining.

Ovarian follicles of animals in Experimental 2group, retained higher percentage of normal morphology (P<0.001) than which in Experimental 1 group and their condition were similar to control group.

These results indicate that the Cetrorelix administration before cancer treatment may protect ovarian tissue against side effects of cisplatin.

Congenital toxoplasmosis is one cause of abortion. Infection can disrupt ovarian cycles and because toxoplasmosis is an infectious disease may have a similar effect on the ovaries. The purpose of this study was to investigate the patho­logical changes in the ovaries due to toxoplasmosis. Tachyzoites of Toxoplasma gondii were harvested from peritoneal fluid of mice, experimentally infected. Two females and one male mouse were housed per cage for mating in the overnight. The pregnant mice were divided into experi­mental and control groups. Experimental group were infected by parasite but the control group received the normal saline. The experimental and control mice were euthanized. Ovaries and uterine horns of animals were removed and prepared for light microscopy. Ovaries of infected pregnant mice presented gross morphological differ­ences compared to the control groups. In ovaries of experimental groups, changes of corpus luteum were observed. The comparison of experimental and control groups revealed that the number of primary follicles, secondary follicle, atretic pri­mary follicles and atretic secondary follicles had significant differences (P≤0.001). Toxoplasma gondii alters ovarian follicular growth and development in mice. In addition, it alters number of different phases of follicles and corpus lu­teum in ovaries of mice.

The origin of neonatal oocyte development is unknown. However, estrogen plays an essential role during development of the female reproductive system. Anastrozole is used as both ovulation stimulating and an anticancer drug. The aim of this study was to evaluate the impact of Anastrozole on follicular development and differentiation in mice.

In the present study, 30 adult female and 15 adult male mice were used. Then, two female mice (at their sterous cycle) were kept with one male mouse in a cage for mating. After observing the vaginal plug (considered as first day of pregnancy) female mice were divided into two groups of control and experimental. In the experimental group, on the 14th day of pregnancy the mice received anastrozole (50 mg/Kg, i.p. injection). After delivery 16 pups were selected in each group. Then 2, 4 and 7 day pups were studies for primordial, primary and growing follicles number.

According to the morphometric studies, in the 2 day pup, the breakdown was not complete in treatment group. However, the number of primordial, primary and growing follicles of 4 and 7 day pups were not significantly difference in the control and experimental groups.

According to the studies, estrogen is necessary for follicular breakdown and maternal anastrozole can reduce the primordial follicles. However, maternal anastrozole and estrogen depression couldn’t effect on the histology of ovarian follicle in neonatal mouse.

Intrauterine Insemination (IUI) remains the first thought of infertility treatment.

To compare the stimulation effects and Pregnancy rate (PR) outcomes of two ovulation induction (OI) medications, human-derived menopausal gonadotrophins (hMGH), Merional (MER), and recombinant follicular stimulating hormone (rFSH), Puregon (PUR), in a cohort of Saudi infertile patients, for better predictability of treatment results.

During a 24-month period, 296 women underwent IUI single treatments. PR’s were correlated with the type of stimulation medication that were prospectively and randomly assigned to each patient, and with the number and size of maturing follicles detected on the hCG injection day.

MER and PUR needed comparable number of days (9.26±4.74 and 9.73±6.27 respectively) before follicles were ready for IUI, although the average amount used from MER, 1199.90 IU, was about double that was used from PUR, 621.08 IU. The overall PR in case of PUR however was nearly double that of MER, 13.28% and 7.14% respectively. The best PR, 16.22%, occurred when the follicles matured within 12-13 days. Three follicles of at least 15-mm diameter on the hCG day had better PR’s than one or two, however when the follicles’ diameters were at least 18-mm, PR was significantly higher, (p=0.013).

MER and PUR had comparable stimulation effects; however PUR had noticeably higher PR. The best PR occurred when the follicles matured within 12-13 days. PR in case of three maturing follicles on the hCG day was better than only one or two, and significantly better when their diameters were at least 18 mm.

Nicotine exposure causes impaired fertility and ovarian dysfunction. The aim of this study was to investigate the possible protective role of melatonin, which is known as an antioxidant agent on altered ovarian functions upon nicotine exposure. A total of 32 female adult NMRI mice were divided randomly into four groups (n=8). The control group received vehicle, while group 2 received nicotine (40 μg/kg) for 15 days and group 3 melatonin (10 mg/kg) for 5 days. Group 4 received both nicotine (40μg/kg) and melatonin (10 mg/kg) for the same periods. All animals were treated intraperitoneally. After autopsy on the 16th day, histopathological and morphometrical examinations were performed and serum estradiol concentrations were measured. The data were analyzed using ANOVA and Tukey post hoc test. A value of p<0.05 was considered significant. Nicotine significantly reduced the number of pre-antral and antral follicles, as well as estradiol concentration compared to the control group (p<0.05). However, the decrease in the number of primordial follicles was not significant in the nicotine treated group. A significant increase in the atretic follicles were observed in group 2 compared to the control group (p<0.05). Moreover, melatonin caused a marked normalization in the number of ovarian follicles and estradiol levels in group 4 compared to group 2. The results from this study suggest that melatonin may have a protective effect against nicotine-induced ovarian changes on the number of different stages of follicle growth.