Remarkable features of ovarian morphology and reproductive hormones in insulin-resistant Zucker fatty (fa/fa) rats.

BACKGROUND: Zucker fatty (fa/fa) rats are a well-understood model of obesity and hyperinsulinemia. It is now thought that obesity/hyperinsulinemia is an important cause of endocrinological abnormality, but to date there have been no reports on the changes in ovarian morphology or the ovarian androgen profile in rat models of obesity and insulin resistance. METHODS: In this study we investigated the effects of obesity and hyperinsulinemia on ovarian morphology and the hormone profile in insulin-resistant Zucker fatty rats (5, 8, 12 and 16 weeks of age, n = 6-7). RESULTS: Ovaries from 5-week-old fatty rats had significantly greater total and atretic follicle numbers, and higher atretic-to-total follicle ratios than those from lean rats. Ovaries from 12- and 16-week-old fatty rats showed interstitial cell hyperplasia and numerous cysts with features of advanced follicular atresia. In addition, serum testosterone and androstenedione levels significantly declined in fatty rats from age 8 to 16 weeks, so that fatty rats showed significantly lower levels of serum testosterone (12 and 16 weeks) and androstenedione (all weeks) than lean rats. This may reflect a reduction of androgen synthesis during follicular atresia. Serum adiponectin levels were high in immature fatty rats, and although the levels declined significantly as they matured, it remained significantly higher in fatty rats than in lean rats. On the other hand, levels of ovarian adiponectin and its receptors were significantly lower in mature fatty rats than in lean mature rats or immature fatty rats. CONCLUSIONS: Our findings indicate that ovarian morphology and hormone profiles are significantly altered by the continuous insulin resistance in Zucker fatty rats. Simultaneously, abrupt reductions in serum and ovarian adiponectin also likely contribute to the infertility seen in fatty rats.

The contributions of resistin and adiponectin gene single nucleotide polymorphisms to the genetic risk for polycystic ovary syndrome in a Japanese population.

Polycystic ovary syndrome (PCOS) is a heterogeneous group of disorders that occur fairly commonly in women of reproductive age and are characterized by a variety of clinical manifestations, including insulin resistance that is independent of obesity. Recent studies suggest that altered adipocytokine gene expression is closely associated with insulin resistance and that single nucleotide polymorphisms (SNPs) modulate the expression and/or function of these genes, thereby affecting insulin sensitivity. With that in mind, we investigated whether SNPs at position -420 of the resistin gene (RETN) and/or -11377 of the adiponectin gene (ADIPOQ) modulate the susceptibility to PCOS. We evaluated the genotypes of 117 women with PCOS and 380 healthy fertile controls and measured the index of insulin resistance and hormonal profiles in the PCOS women. The RETN-420G/G homozygous variant genotype occurred significantly more frequently among the PCOS group than among the control group (15.4% vs. 8.4%, p = 0.035). PCOS women with the RETN-420G/G genotype also showed significantly higher BMIs and greater insulin resistance than those with RETN-420 C/C or C/G genotypes. The ADIPOQ SNP at -11377 showed no association with PCOS. We conclude that the RETN G/G at -420 genotype is associated with PCOS in Japanese women.

Polycystic ovary syndrome is associated with genetic polymorphism in the insulin signaling gene IRS-1 but not ENPP1 in a Japanese population.

Recent studies indicate that insulin resistance resulting from altered post-receptor signaling is associated with polycystic ovary syndrome (PCOS). We hypothesized that insulin receptor substrate-1 (IRS-1) Gly972Arg polymorphism and/or ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1) Lys121Gln polymorphism predisposes women to PCOS and that these polymorphisms also affect anthropometric variables, glucose metabolism and androgen synthesis. To test those ideas, we studied the genotypes, indexes of insulin resistance, and hormone profiles in 123 Japanese women with PCOS and 380 healthy Japanese controls. We found that there were significantly more IRS-1 972Arg carriers among the PCOS patients than among the healthy controls (10.6% vs. 4.8%, p=0.029), which is consistent with our finding that women carrying the IRS-1 972Arg allele had a significantly increased risk of developing PCOS (odds ratio: 3.31, 95% confidence interval: 1.49-7.35). By contrast, the ENPP1 Lys121Arg polymorphism was distributed equally among PCOS patients and controls. In addition, neither of these polymorphisms studied affected the anthropometric variables, metabolic parameters or androgen levels of women with PCOS. We conclude that the IRS-1 Gly972Arg polymorphism is associated with PCOS in the Japanese population.

Hyperstimulation and a gonadotropin-releasing hormone agonist modulate ovarian vascular permeability by altering expression of the tight junction protein claudin-5.

We investigated the mechanism by which a GnRH agonist (GnRHa) affects ovarian vascularity, vascular permeability, and expression of the tight junction protein claudin-5 in a rat model of ovarian hyperstimulation syndrome (OHSS). Hyperstimulated rats received excessive doses of pregnant mare serum gonadotropin (PMSG; 50 IU/d) for 4 consecutive days, from d 25 to 28 of life, followed by 25 IU human chorionic gonadotropin (hCG) on d 29. Control rats received 10 IU PMSG on d 27 of life, followed by 10 IU hCG on d 29. GnRHa (leuprolide 100 microg/kg.d) was administered to some hyperstimulated rats either on d 29 and 30 (short-term GnRHa treatment) or from d 25 to 30 (long-term GnRHa treatment). Ovarian vascular density (vessels per 10 mm(2)) and vessel endothelial area (percent) were assessed by immunohistochemical analysis of the distribution of von Willebrand factor, whereas vascular permeability was evaluated based on leakage of Evans blue. High doses of PMSG and hCG significantly increased ovarian weight, vascular permeability, vascular density, and the vessel endothelial area and significantly reduced expression of claudin-5 protein and mRNA. All of these effects were significantly and dose-dependently inhibited by administration of GnRHa. This suggests that reduced expression of claudin-5 plays a crucial role in the increased ovarian vascular permeability seen in OHSS and that its expression can be modulated by GnRHa treatment. Indeed, preventing redistribution of tight junction proteins in endothelial cells and the resultant loss of endothelial barrier architecture might be the key to protecting patients against massive extravascular fluid accumulation in cases of OHSS.

Identical changes in Bax expression, but not Fas ligand expression, occur in structural luteolysis in gonadotropin releasing hormone agonist- and prolactin-treated superovulated rats.

Structural luteolysis induced by gonadotropin releasing hormone agonist (GnRHa) or prolactin (PRL) is defined as histological involution of the corpus luteum. We reported that one of the mechanisms of structural luteolysis induced by PRL was tissue remodeling by matrix metalloproteinase (MMP) and also apoptosis in superovulated rats. We also reported that GnRHa induced structural luteolysis with elevation of MMP. In this study, we investigated whether GnRHa caused apoptosis in mature corpus luteum of superovulated rats and also examined the expression of apoptosis-related molecules (Fas, Fas ligand (FasL), Bcl-2, Bax). We gave 4-day GnRHa treatment 5 days after hCG injection to immature female rats treated with pregnant mare surum gonadotrophin (PMSG) and hCG to induce structural involution of mature corpus luteum. PMSG-hCG-treated rats without GnRHa treatment, rats treated with bromocryptine (Brom) to induce functional luteolysis and rats treated with Brom followed by PRL (Brom+PRL) to mimic the PRL surge to induce structural luteolysis as we previously reported were used for comparison. GnRHa treatment caused structural luteolysis characterized by structural involution, a decrease in the serum progestin level, and apoptotic bodies as well as structural luteolysis induced by Brom+PRL. FasL expression in corpora lutea was elevated after Brom treatment, but there was no elevation of FasL after GnRHa treatment started. FasL expression decreased and Bax expression increased in structural luteolysis induced by GnRHa as well as Brom+PRL treatment, although Fas and Bcl-2 expression did not change throughout the luteal phase. In summary, both GnRHa and Brom+PRL caused structural luteolysis, one of whose mechanisms was apoptosis with an increase in Bax expression, but not with an identical change in FasL expression. It is speculated that the significance in alteration of FasL may involve some mechanism other than apoptosis.

Successful twin pregnancy in panhypopituitarism caused by suprasellar germinoma.

BACKGROUND: Pregnancy in a woman with hypopituitarism from a suprasellar germinoma is rare. CASE: A 27-year-old woman presented with panhypopituitarism from a suprasellar germinoma. She had diabetes insipidus, hypothyroidism, adrenal cortex dysfunction, and hypogonadotropic ovarian failure. When treated with thyroxin, cortisol, antidiuretic hormone, human menopausal gonadotropin, and human chorionic gonadotropin, she conceived and gave birth to healthy twins. CONCLUSION: Hormonal replacement therapy and ovulation induction resulted in a successful pregnancy in a woman with panhypopituitarism.

Low-molecular-weight dextran infusion is more effective for the treatment of hemoconcentration due to severe ovarian hyperstimulation syndrome than human albumin infusion.

The most severe complication of ovarian hyperstimulation syndrome (OHSS) is thromboembolism, which is related to hemoconcentration. Dextran 40 infusion has greater effectiveness for the treatment of hemoconcentration due to OHSS than does human albumin infusion.

Gonadotropin-releasing hormone agonist administration reduced vascular endothelial growth factor (VEGF), VEGF receptors, and vascular permeability of the ovaries of hyperstimulated rats.

OBJECTIVE: Using hyperstimulated rats, to elucidate the mechanisms of gonadotropin-releasing hormone agonist (GnRH-a) treatment to prevent early ovarian hyperstimulation syndrome (OHSS). DESIGN: Descriptive study of hyperstimulated rats as an early OHSS model with Western blot analysis, Northern blot hybridization, and vascular permeability assay. SETTING: Experimental laboratory research. ANIMAL(S): Sprague-Dawley female rats were used for collecting ovarian samples. INTERVENTION(S): Hyperstimulated rats received consecutive GnRH-a treatment from the start of pregnant mare serum gonadotropin (PMSG) treatment through 2 days after hCG administration. MAIN OUTCOME MEASURE(S): Expressions of vascular endothelial growth factor (VEGF), VEGF receptor-1 (VEGFR-1: Flt-1), VEGF receptor-2 (VEGFR-2: KDR/Flk-1), and vascular permeability by Evans blue leakage. RESULT(S): GnRH-a treatment significantly reduced expressions of VEGF, VEGFR-1, and VEGFR-2 both in mRNA and protein levels in the ovaries of hyperstimulated rats. GnRH-a treatment also reduced vascular permeability in the ovaries of hyperstimulated rats. CONCLUSION(S): It is speculated that GnRH-a treatment may prevent early OHSS by reducing vascular permeability through the decrease in VEGF and its receptors.

Continuous follicle-stimulating hormone exposure from pituitary adenoma causes periodic follicle recruitment and atresia, which mimics ovarian hyperstimulation syndrome.

CONTEXT: Follicle-stimulating hormone (FSH)-secreting pituitary adenoma is usually a nonfunctioning tumor, but in rare cases it may develop into ovarian hyperstimulation. Several reports have revealed that serum FSH levels are normal to slightly high in patients with combined FSH-secreting pituitary adenoma with ovarian hyperstimulation. This finding is different from iatrogenic ovarian hyperstimulation syndrome (OHSS), which is associated with extremely high levels of FSH. OBJECTIVE: To describe the clinical course of two patients who developed OHSS from FSH-secreting pituitary adenoma. RESULTS: Endocrine studies of the two cases revealed that FSH levels were normal or slightly increased, but luteinizing hormone levels were low to undetectable. Their estradiol (E2) levels were intriguing: levels fluctuated drastically over 6 weeks in Case 1, but stayed flat in Case 2. Ultrasonographic examinations showed bilaterally enlarged multicystic ovaries, and magnetic resonance imaging indicated pituitary tumors. Transsephenoidal resection of the tumors ameliorated the symptoms and pathological diagnosis revealed FSH-secreting pituitary adenomas. CONCLUSION: As is not the case in iatrogenic OHSS, even a small to moderate amount of FSH stimulation, which is continuously secreted by a pituitary adenoma, can cause ovarian hyperstimulation. Although FSH-secreting pituitary adenoma can cause ovarian hyperstimulation, an extremely high amount of E2 biosynthesis from granulosa cells seldom occurs.

Spontaneous ovarian hyperstimulation syndrome and pituitary adenoma: incidental pregnancy triggers a catastrophic event.

OBJECTIVE: To report a rare case of spontaneous ovarian hyperstimulation syndrome (OHSS) associated with spontaneous pregnancy and a FSH-secreting pituitary adenoma. DESIGN: Case report. SETTING: University hospital. PATIENT(S): A 32-year-old woman with spontaneous OHSS. INTERVENTION(S): Transsphenoidal resection of the tumor. MAIN OUTCOME MEASURE(S): Regression of the symptoms of OHSS and hyperestrogenemia. RESULT(S): At presentation, the patient's ovaries were markedly enlarged and massive ascites was seen. Her serum E(2) level was markedly elevated, but her LH level was low, and FSH was within the normal range. In addition, her TSH level was normal, and hCG was appropriate for the date of pregnancy. Subsequently, the patient developed massive thrombophlebitis in her right internal jugular and subclavian veins. Termination of the pregnancy ameliorated the accumulation of ascites, but ovarian enlargement and hyperestrogenemia persisted. No mutations of the FSH receptor, LH receptor, or aromatase genes were detected, but magnetic resonance imaging (MRI) of the head revealed a pituitary adenoma. After transsphenoidal resection of the tumor, the patient got better. CONCLUSION(S): A gonadotropin-secreting adenoma caused ovarian hyperstimulation (ovarian enlargement and hyperestrogenemia). In addition, spontaneous pregnancy and intrinsic hCG increased vascular permeability, which complicated the patient's disease.

Association between polycystic ovary syndrome and female-to-male transsexuality.

BACKGROUND: The aim of this study is to understand the relationship between polycystic ovary syndrome (PCOS), altered hormonal characteristics and insulin resistance in female-to-male (FTM) transsexual patients. METHODS: We studied 69 Japanese FTM cases, aged 17-47 years, who were seen in the Gender Identity Disorder Clinic of Sapporo Medical University Hospital between December 2003 and May 2006. The subjects had never received hormonal treatment or sex re-assignment surgery. Prior to treatment, they received physical examinations entailing measurement of anthropometric, metabolic and endocrine parameters, after which we compared the values obtained according to the presence or absence of PCOS and/or obesity. Insulin resistance was determined using the homeostasis model assessment of insulin resistance (HOMA-IR). RESULTS: Of the 69 participating FTM cases, 40 (58.0%) were found to have PCOS. Of the 49 for whom HOMA-IR was calculated, 15 (30.6%) also showed insulin resistance, whereas of the 59 for whom adiponectin was measured, 18 (30.5%) showed hypoadiponectinaemia. Of 69 for whom androgens were measured, 29 (39.1%) showed hyperandrogenaemia. Insulin resistance was associated with obesity but not with PCOS. In contrast, hyperandrogenaemia was associated with both PCOS and obesity. CONCLUSION: FTM transsexual patients have a high prevalence of PCOS and hyperandrogenaemia.

Successful delivery after vaginal radical trachelectomy for invasive uterine cervical cancer.

A 32-year-old Japanese woman was diagnosed as having stage Ib1 adenocarcinoma by diagnostic laser conization at a local hospital. She was admitted to our hospital for fertility-sparing treatment. A radical trachelectomy (RT) was performed using the laparoscopic vaginal procedure. The procedure was started with a laparoscopic pelvic lymphadenectomy. As the lymph nodes were tumor free, RT was carried out transvaginally. The excised uterine cervix and lymph nodes were pathologically negative for cancer. Eight months after the operation, the patient became pregnant without any artificial reproduction techniques. At 17 weeks of gestation, she was admitted to our hospital again for a threatened abortion. Continuous tocolytic treatment with ritodrine and daily administration of a granulocyte elastase inhibitor vaginal suppository were given. At 32 weeks of gestation, she underwent emergency cesarean section because of sudden premature rupture of the membranes. A girl weighing 1991 g was delivered, with Apgar scores of 7 and 8 at 1 and 5 min, respectively. Both the mother and the baby were discharged without trouble. This is the first successful case in Japan of delivery after vaginal RT for invasive uterine cervical cancer.

Altered expression of Fas/Fas ligand/caspase 8 and membrane type 1-matrix metalloproteinase in atretic follicles within dehydroepiandrosterone-induced polycystic ovaries in rats.

One of the characteristics of polycystic ovary syndrome (PCOS) is the presence of cystic follicles in various stages of growth and atresia, the latter of which is known to be the result of apoptosis and tissue remodeling. To further investigate the process of follicular atresia, we compared ovarian expression and localization of Fas, Fas ligand (FasL), casapse-8 and membrane-type1 matrix metalloproteinase (MT1-MMP) in rats treated with dehydroepiandrosterone (DHEA) as a model of PCOS, and in control rats. We found that the numbers of TdT-mediated dUTP-biotin nick end-labeling (TUNEL)-positive follicles were significantly higher in ovaries from PCOS rats than in those from control rats (P < 0.05), as were ovarian levels of FasL mRNA and protein, processed caspase-8 protein and MT1-MMP mRNA. Correspondingly, we also observed an increase in the level of MTI-MMP catalytic activity and a decrease in the level of pro-caspase-8 protein. In addition, immunohistochemical analyses showed that MT1-MMP and FasL co-localize with TUNEL-positive apoptotic granulosa cells within atretic follicles of PCOS ovaries. Our results suggest that under the PCOS-like conditions induced by DHEA, the Fas/FasL/Caspase-8 (death receptor dependent) pathway is pivotal for follicular atresia, and that increased levels of MT1-MMP likely play an important role in tissue remodeling during structural luteolysis.

Continuation of GnRH agonist administration for 1 week, after hCG injection, prevents ovarian hyperstimulation syndrome following elective cryopreservation of all pronucleate embryos.

BACKGROUND: An approach consisting of elective cryopreservation of all embryos has been proposed for patients at risk of ovarian hyperstimulation syndrome (OHSS). Although elective cryopreservation can prevent pregnancy-induced late OHSS, it cannot prevent early OHSS. Early OHSS is reported to have been complicated with thromboembolism. The study was carried out to assess the efficacy with which the continued administration of GnRH agonist for 1 week after 5000 IU of hCG injection could prevent early OHSS. METHODS: This study employed an open controlled clinical trial at three centres for treatment of infertility in Sapporo. A total of 138 patients at risk of OHSS during IVF-embryo transfer from January 1, 1998 to December 31, 1999, were assigned in turn either to a group with elective cryopreservation of all pronucleate embryos (n = 68) or to one with continuation of GnRH agonist administration for 1 week after hCG injection following elective cryopreservation (n = 70). Subsequently, they were transferred in hormone replacement cycles. The development of severe OHSS (ascites, haemoconcentration) was compared between the two groups. RESULTS: A total of 10% of patients developed severe OHSS necessitating hospitalization because of a marked increase in ascites in the upper abdomen and the haemoconcentration in the elective cryopreservation alone group. On the other hand, none developed severe OHSS in the GnRH agonist continuation group. CONCLUSIONS: In our study, continuation of GnRH agonist for 1 week after hCG injection prevented severe early OHSS following elective cryopreservation of all embryos. This treatment is safe and cost-beneficial, and should be performed promptly for patients at risk of OHSS.

Expression of vascular endothelial growth factor and E-cadherin in human ovarian cancer: association with ascites fluid accumulation and peritoneal dissemination in mouse ascites model.

Ascites formation and peritoneal dissemination are critical problems in patients with advanced ovarian cancer. Vascular endothelial growth factor (VEGF), also known as angiogenic growth factor, is a potent mediator of peritoneal fluid accumulation and angiogenesis of tumors. E-Cadherin is an adhesion molecule that is important for cell-to-cell interaction. To elucidate the molecular mechanism of ascites formation and peritoneal dissemination of ovarian cancer, we examined the expression of VEGF and E-cadherin in different ovarian cancer cell lines and utilized nude mice to compare the biological characteristics of ovarian cancer cells. Three human ovarian cancer cell lines (AMOC-2, HNOA and HTBOA) were used in this study. Expression of genes was analyzed by northern blotting and RT-PCR methods. AMOC-2 expressed E-cadherin, but not VEGF. HNOA expressed VEGF without E-cadherin expression. HTBOA expressed both VEGF and E-cadherin. Each human ovarian cancer model revealed a specific feature. The AMOC-2 mouse had a single large peritoneal tumor without ascites or remarkable peritoneal dissemination. HTBOA and HNOA mice had bloody ascites and marked peritoneal dissemination. Introduction of VEGF antisense into HTBOA cells could inhibit the ascites formation. It is suggested that VEGF is important for the ascites formation via the increased vascular permeability effect. The deregulation of E-cadherin expression might be involved in the peritoneal dissemination. These molecules are important for the formation of specific features of advanced ovarian cancer. Ovarian cancer cell lines that had different gene expression patterns produced nude mouse human ovarian cancer models with different characteristics.