The relationship between cumulus cell expansion, cocyte maturation and metabolic cooperativitiy was investigated by using mouse and pig cocyte-cumulus complexes in vitro. Cocyte germinal vesicle breakdown (GVBD) and cumulus expansion were manipulated with hormones or reagents which increase intracellular cAMP leveL Metabolic cooperativity between oocyte and cumulus cells was assessed by determination of the fraction of radiolabelled uridine marker that was transferred from the cumulus mass to the oocyte. Uptake of uddine marker by mouse and pig cumulus mass was increased by about fourfold of basal level with the stimulation of hormones (human choriononic gonadotrophin, HCG; follicle stimulating hormone, FSH) or cyclic AMP sttmulators (3-isobutyl-1-methylxanthine, IBMX; forskolin) during culture. However, the fraction of uridine that was transferred from the cumulus mass to the cocyte (transfer ratio) was gradually decreased during culture, irrespective with the presence of hormones or stimulators. The decrease of the transfer ratio was not correlated with the state of occyte whether they have GV or not, or with the degree of cumulus expansion. In mouse complexes, HCG induced more significant reducton of transfer ratio than other treatments. These results do not support the idea that modulations of metabolic cooperativity between cumulus cells and oocytes are important for the regulation of meiotic resumption in mammals.
Kim, Suh-Kyung;Kim, Young-Tae;Kim, Sun-Haeng;Rha, Jung-Ryul;Ku, Byung-Sahm
Clinical and Experimental Reproductive Medicine
/
v.17
no.2
/
pp.115-121
/
1990
Ultrasonically guided oocyte collection gradually replaces laparoscope in many IVF center. In present study, we compare the efficacy of both methods in our IVF program. Totally 377 cycles which were undertaken in vitro fertilization treatment were divided into 2 groups. Ultrasonically guided transvaginal follicular aspiration was performed in 188 cycles and laparoscopic follicular aspiration was performed in 189 cycles under local anesthesisa. The mean age for both groups was similar. Follicular recruitment was achieved with human menopausal gonadotropin (hMG) or a com bination of clomiphene citrate and hMG or a combination of FSH and hMG. In the ultrasonically guided aspiration group, 1821 follicles were aspirated with 61.8% of recovery rate (1125 oocytes), 81.5% of embryo transfer rate (145 cycles) and (17%), 26 cases intrauterine pregnancies were estabilished. In the laparoscopic group, 604 follicles were aspirated with 68.7% recovery rate (445 oocytes) and a 79.9% ET rate (127 cycles), 11 cases (8.7%) intrauterine pregnancies were estabilished. A valid comparison of these data is not possible because the 2 groups are dissimilar for factors known to influence oocyte development and recovery. No statistically significant differences could be demonstrated between 2 groups in all but the recovery rate and clinical pregnancy rate, In ultrasound group, the clinical pregnancy rate was significantly higher than that of laparoscope group. The potentially detrimental effect of CO2 pnemoperitonium present during laparoscope but not in ultrasound guided recovery on ova quality may underlie the observed difference in the clinical pregnancy rate between the 2 groups. Ultrasound guided aspiration seems to be as effective as laparoscopy in terms of oocyte retrieval and conception rate. Furthermore, the procedure is simple and inexpensive, it may replace laparoscopy as a method for oocyte collection in most patients who undergo IVF.
Despite increasing success rate of IVF, poor response to ovarian stimulation remains a problem. So, attempts to improve ovarian responses, for example, by using combined gonadotropin-releasing hormone analogue(GnRH-a) and human menopausal gonadotropin(hMG) have shown limited success. It is reported that response of granulosa cells in vitro to FSH is stimulated by co-incubation with IGF-l, and IGF-l production can be increased by growth hormone. This suggest that combination regimen of G.H. and hMG may augment follicle recruitment. In fifteen patients who had previous history of poor ovarian response to gonadotropin stimulation after pituitary suppression with mid -luteal GnRH-a, the effectiveness of cotreatment with G.H. in IVF program was evaluated using a combination regimen of G.R. and hMG at Korea University Hospital IVF Clinic. Ovarian responses to gonadotropin stimulation in control and GH-treated cycles assessed by total dose and duration of hMG treatment, follicular development and peak $E_2$ level, number of eggs retrieved, and fertilization rates were also assessed. In each group, serum and follicular fluid IGF-1 concentrations on day of egg collection were measured by RIA after acidification and extraction by reveresed phase chromatography. Patients receiving G.H. required fewer days and ampules of gonadotropins, developed more oocytes, and more embryos transferred. But, the differences were not statistically significant, except the duration of hMG treatment. Our data showed a significantly higher concentration of IGF-l in the serum, not in the follicular fluid, of patients treated with G.H. compared with control group. These data suggest that growth hormone treatment does not improve the ovarian response in women with limited ovarian reserve to gonadotropin stimulation for IVF.
Park, Joon-Cheol;Lim, Su-Yeon;Jang, Tae-Kyu;Bae, Jin-Gon;Kim, Jong-In;Rhee, Jeong-Ho
Clinical and Experimental Reproductive Medicine
/
v.38
no.1
/
pp.42-46
/
2011
Objective: This study was aimed to investigate endometrial histology and to find predictable clinical factors for endometrial disease (hyperplasia or cancer) in women with polycystic ovary syndrome (PCOS). Methods: We investigated the endometrial histology and analyzed the relationship between endometrial histology and clinical parameters, such as LH, FSH, estradiol, testosterone, fasting and 2 hours postprandial glucose and insulin, insulin resistance, body mass index, endometrial thickness, menstrual status from 117 women with PCOS. Statistical analysis was performed with chi square and t-test, p-value<0.05 was considered as statistically significant. And receiver operating characteristic curve was used to find predictable clinical factors for endometrial disease and to decide the cuff off values. Results: In 117 women with PCOS, endometrial histologic profiles are as follows: proliferative phase in 90 women (76.9%), endometrial hyperplasia in 25 women (21.4%), and endometrial cancer in 2 women (1.7%). Of 25 women with endometrial hyperplasia, simple hyperplasia without atypia, complex hyperplasia without atypia and complex hyperplasia with atypia were diagnosed in 15 (12.8%), 6 (5.1%), 4 (3.4%) women, respectively. Age and endometrial thickness were significantly related with endometrial disease, p=0.013 and p=0.001, respectively. At the cut off level of 25.5 years in age, sensitivity and specificity predicting for endometrial disease were 70.4% and 55.6%, respectively (p=0.023). At the cut off level of 8.5 mm in endometrial thickness, sensitivity and specificity were 77.8% and 56.7%, respectively (p=0.000). Conclusion: In women with PCOS, the incidence of endometrial hyperplasia and cancer were 21.4% and 1.7%. The age and endometrial thickness may be used as clinical determining factors for endometrial biopsy.
The role of amino acids in culture media for IVF-ET was examined in a total of 76 cycles. Patients received clomiphene citrate (CC) followed by hMG or GnRH-a combined with gonadotropins (FSH/hMG) for controlled ovarian hyperstimulation. Severe male (<$4{\times}10^6$ motile sperm) or age factor (>39 y) patients were excluded in this study. Pregnancy was classified as clinical if a gestational sac or fetal cardiac activity was seen on ultrasound. No significant differences were found in age, duration of infertility, follicle size, the level of $E_2$ on the day of hCG injection, the mean number of oocytes retrieved, total motile sperm count, fertilization rate and the mean number of embryos transferred between bHTF (without amino acids) and mHTF (with amino acids) groups. However, total ampules of gonadotropins were higher (p<0.01) in mHTF group than bHTF group. Significantly (p<0.05) more clinical pregnancies were recorded in mHTF group (13/30) compared with bHTF group (9/46). The multiple pregnancy rates were 11.1% in bHTF group and 7.7% in mHTF group. There were one ectopic pregnancy in mHTF group and one heterotopic pregnancy in bHTF group. Abortion rates were 22.2% in bHTF group and 7.7% in mHTF, respectively. The ongoing pregnancy or livebirth rate was significantly (p<0.05) higher in mHTF group (12/30) than bHTF group (7/46). These results suggest that the addition of amino acids in culture media is essential for culture of zygotes in vitro and adjustment of energy substrates in phosphate-free culture media appears to be beneficial for human IVF-ET procedure.
In all female mammals, reproductive system is one of the first biological systems to show age-related decline. Female mammals in reproductive aging, though the phenomena is somewhat species-specific, start to show declining fertility and changes of numerous physiological functions. This review will present a current information on the aging of the female reproductive hormonal axis and introduce three useful rodent models for studying this field. Middle age($8{\sim}12$ months old) in female rats and mice is comparable to the stage prior to the entry of menopause in human. In this period pulsatile and surge GnRH secretion from hypothalamus gradually attenuated, then reduced pulsatile and surge LH secretion is followed consequently. This age-related defects in GnRH-LH neuroendocrine axis seem to be highly correlated with the defects in brain signals which modulate the activities of GnRH neuron. Many researchers support the idea which the age-related hypothalamic defects are the main cause of reproductive aging, but some ovarian factors such as inhibin response also could contribute to the induction of reproductive senescence. Some rodent models are quite valuable in studying the reproductive aging. The follitropin receptor knockout(FORKO) mice, both of null and haploinsufficient state, could produce depletion of oocyte/follicle with age. Dioxin/aryl hydrocarbon receptor(AhR) knockout mice also show severe ovarian defects and poor reproductive success early in their life compared to the age-matched normal mice. Further studies on the reproductive aging will be a great help to evaluate the benefits and risks of hormone replacement therapy(HRT) and to improve the safety of HRT.
It is well known that adipose tissue or body fat has been proved as a crucial component of brain-peripheral axis which can modulate the activities of reproductive hormonal axis in female mammals including rodents and human. Concerning the male reproduction, however, the role of adipose tissue has not been thoroughly studied. The present study was carried out to elucidate the effect of a high-fat (HF) diet on the reproductive system of postpubertal male rats. The HF diet (45% energy from fat, HF group) was applied to male rats from week 8 after birth for 4 weeks. The blood glucose levels, body and tissue weights were measured. Histological studies were performed to assess the structural alterations in the reproductive tissues. To determine the transcriptional changes of reproductive hormone-related genes in hypothalamus and pituitary, total RNAs were extracted and applied to the semi-quantitative reverse transcription polymerase chain reaction (RT-PCR). Body weights (p<0.01) and blood glucose levels (p<0.01) of HF group were significantly higher than those of control animals. Similarly, the weights of epididymis (p<0.05), prostate (p<0.01), seminal vesicle (p<0.01) in HF group were higher than control levels. The weights of testis were not changed. The weights of kidney (p<0.001) and spleen (p<0.01) were significantly higher than control levels while the adrenal and pancreas weights were not changed. There were only slight alterations in the microstructures of accessory sex organs; the shape of luminal epithelial cells in epididymis from HF group were relatively thicker and bigger than those from control animals. In the semi-quantitative RT-PCR studies, the mRNA levels of hypothalamic GnRH (p<0.05) in HF group were significantly higher than those from the control animals. The mRNA levels of kisspeptin in HF group tend to be higher than control levels, the difference was not significant. Unlike the hypothalamic GnRH expression, the mRNA levels of pituitary $LH{\beta}$ and $FSH{\beta}$ were significantly decreased in HF group (p<0.05). The present study indicated that the 4-weeks feeding HF diet during the postpubertal period can alter the hypothalamus-pituitary (H-P) neuroendocrine reproductive system These results suggest that the increased body fat and the altered leptin input might disturb the H-P reproductive hormonal activities in male rats, and the changed activities seem to be responsible for the changes of tissue weights in accessory sex organs.
This research was designed to investigate the effects of Estromon including FGF271 (Female Growth Factor 271) which was developed as a phytoestrogen for post- and pre-menopausal syndrome (PMS). The oral administration of two capsules of Estromon twice a day for 3 months significantly improved PMS (Post-/Premenopausal Syndrome) about 5 times more than placebo group (OR=5.04, 95% C.1. 1.40-18.14). In the group of 24 patients having taken Estromon, the concentration of alkaline phosphatase asn the bone marker decreased by -9.3${\pm}$9.5 IU/L after 3 months with a statistic significance. Since the concentration of osteocalcin as the other bone marker also decreased in more patients in Estromon group than in placebo group, the bone density might be expected to be improved in long-term treatment. Serum human growth hormone level increased in 17 out of 24 patients. Triglycerides decreased by -8.0${\pm}$40 (mg%) after 1 month and by -4.4${\pm}$36 (mg%) after 3 months in Estomon group while triglycerides increased in both cases in placebo group (p.0.01). Therefore, PMS patients might benefit from Estromon as a phytoestrogen supplement without any serious side effects.
The present study was conducted to investigate the involvement of nitric oxide (NO) in cumulus expansion, oocyte mortality and meiotic maturation of porcine cumulus enclosed oocytes (CEOs) cultured in two different models when gonadotropins, including follicle-stimulating hormone (FSH) and human chorionic gonadotropin (hCG) were presented or not. And the interaction between NO and $\beta$-mercaptoethanol ($\beta$-ME), a free radical scavenger was also investigated. Two models refer to spontaneous maturation model and hypoxanthine (HX) medium model. All the 3,433 eligible CEOs were incubated at $39^{\circ}C$ and the cumulus expansion, oocyte morphology and nuclear phase were evaluated 44 h after incubation. (1) In spontaneous maturation model, NO stimulates the cumulus expansion and $\beta$-ME delayed it. NO doesn't affect the oocyte meiotic resumption but inhibits the oocytes to develop to metaphase II. (2) In HX medium model, NO or $\beta$-ME doesn't affect the expansion in the absence of gonadotropins, but in the presence of gonadotropins, NO or $\beta$-ME inhibits the expansion. In the presence of gonadotropins, NO inhibits the oocyte meiotic resumption and it especially inhibits the oocyte to develop to metaphase II, and $\beta$-ME reverses such inhibitory effects. The cooperation of gonadotropins and $\beta$-ME stimulates the meiotic resumption and especially, promotes the CEOs to develop to metaphase II in both models. Moreover, HX might contribute to the fragility of oocyte zona pellucida and gonadotropins, nitric oxide and $\beta$-ME could alleviate it separately, and cooperatively. It is concluded that NO exerts different functions in two models and $\beta$-ME affected the functions of NO in different models.
Kwon, Su-Kyoung;Kim, Chung-Hoon;Lee, Kyung-Hee;Jeon, Il Kyung;Ahn, Jun-Woo;Kim, Sung-Hoon;Chae, Hee-Dong;Kang, Byung-Moon
Clinical and Experimental Reproductive Medicine
/
v.40
no.3
/
pp.131-134
/
2013
Objective: To evaluate the effect of the addition of estradiol to luteal progesterone supplementation in GnRH antagonist cycles for infertile patients undergoing IVF/ICSI. Methods: One hundred and ten infertile patients, aged 28 to 39 years, were recruited for this prospective randomized study. They were randomly assigned to receive vaginal progesterone gel (Crinone) along with 4 mg estradiol valerate (group 1, n=55) or only Crinone (group 2, n=55) for luteal support. A GnRH antagonist multiple dose protocol using recombinant human FSH was used for controlled ovarian stimulation (COS) in all of the subjects. The COS results and pregnancy outcomes of the two groups were compared. Results: Group 1 and 2 were comparable with respect to the patient characteristics. The COS and IVF results were also comparable between the two groups. There were no differences in the clinical pregnancy rate (PR) and multiple PR between the two groups. However, the embryo implantation rate were significantly higher in group 1 than that in group 2 (22.2% vs. 13.3%, p=0.035). The incidence of luteal vaginal bleeding (LVB) was significantly lower in group 1 (7.4% vs. 27.8%, p=0.010). Conclusion: The addition of estradiol to luteal progesterone supplementation in GnRH antagonist cycles reduces the incidence of LVB and increases the embryo implantation rate in infertile patients undergoing IVF/ICSI.
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