Compatible cut-off values for luteinizing hormone and the luteinizing hormone/follicle-stimulating hormone ratio in diagnostic criteria of the Japan Society of Obstetrics and Gynecology for polycystic ovary syndrome.

Aim: The abnormal secretion of luteinizing hormone (LH) is one of the typical features of polycystic ovary syndrome (PCOS) and adopted in the diagnostic criteria of the Japan Society of Obstetrics and Gynecology (JSOG). We investigated cut-off values for LH and the LH/follicle-stimulating hormone (FSH) ratio in resent two measurement systems for the diagnosis of PCOS.

Methods: Ninety-nine controls and 106 patients with PCOS were enrolled.

Biotin levels in blood and follicular fluid and their associations with pregnancy outcomes in IVF/ICSI patients.

It has been shown that biotin, a water-soluble vitamin (B7), plays roles in reproductive functions, such as oocyte maturation and embryo development, in experimental animals. On the other hand, little is known about the clinical effects of biotin on human reproduction. In this study, serum and follicular fluid biotin levels were measured in patients who underwent in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI), and their associations with reproductive outcomes were evaluated.

A novel PCOS rat model and an evaluation of its reproductive, metabolic, and behavioral phenotypes.

Background: Although animal models of PCOS have been used in many studies, none of them can reproduce both the reproductive and metabolic phenotypes of PCOS. In addition, behavioral parameters have not been evaluated in PCOS animal models.

Purpose: We tried to produce an improved rat model of PCOS, and the reproductive, metabolic, and behavioral phenotypes of the model rats were evaluated.

The effects of androgens on metabolic functions in females.

The metabolic effects of androgens and their underlying mechanisms in females have been revealed by recent studies. An excess of androgens can have adverse effects on feeding behavior and metabolic functions and induce metabolic disorders / diseases, such as obesity, insulin resistance, and diabetes, in women and experimental animals of reproductive age. Interestingly, these effects of androgens are not observed in ovariectomized animals, indicating that their effects might be dependent on the estrogen milieu.

Effects of gonadal status and the estrogen milieu on hypothalamic oxytocin gene expression and serum oxytocin levels in female rats.

Oxytocin (OT) and its receptor (OTR) play various roles in the central and peripheral regulation of appetite and body weight. Previously, we have shown that the administration of OT markedly decreased appetite and body weight gain in ovariectomized (OVX) obese rats. In addition, recent studies have shown that the endogenous OT system is also affected by endogenous or exogenous estrogen.

The influence of psychological stress in early life on sexual maturation and sexual behavior in male and female rats.

Purpose: We studied the influence of psychological stress during the early neonatal period on sexual maturation and sexual behavior in rats.

Methods: Neonatal male and female rats were divided into control (C) and maternal separation (MS) groups (n = 20-24 per group). The pups in the MS groups were placed in isolation cages for 240 minutes/d from postnatal days 2-11.

The reduction in sexual behavior of adult female rats exposed to immune stress in the neonatal period is associated with reduced hypothalamic progesterone receptor expression.

Purpose: We examined the mechanism by which neonatal immune stress reduces the sexual behavior of female rats in adulthood.

Methods: Neonatal female rats were randomly divided into 3 groups: control (n = 11), postnatal day 10 lipopolysaccharide (PND10LPS) (n = 23), and PND25LPS (n = 11) groups, which received intraperitoneal injections of LPS (100 μg/kg) or saline on PND10 and 25. Daily inspections of the vaginal opening (VO) were performed from PND27 to PND37.

The effects of chronic oxytocin administration on body weight and food intake in DHT-induced PCOS model rats.

Polycystic ovary syndrome (PCOS) is commonly associated with metabolic disorders, which are exacerbated by obesity. Recent studies have revealed that oxytocin contributes to metabolic, appetite, and body weight regulation. In the present study, we evaluated the effects of chronic administration of oxytocin on body weight, food intake, and fat mass in a dihydrotestosterone-induced rat model of PCOS.

Oxytocin treatment reduced food intake and body fat and ameliorated obesity in ovariectomized female rats.

Recent studies have shown that oxytocin reduces food intake and body weight gain and promotes lipolysis in some species, including humans. Interestingly, these effects of oxytocin are more marked in obese individuals. Although the menopausal loss of ovarian function induces increased visceral adiposity and some metabolic disorders, no safe medical interventions for these conditions have been established.

The reduction in sexual behavior induced by neonatal immune stress is not related to androgen levels in male rats.

Purpose: It is known that various types of stress in early life increase the incidence of diabetes, myocardial infarctions, and psychiatric disorders in adulthood. We examined the mechanism by which neonatal immune stress reduces sexual behavior in adult male rats.

Methods: Male rats were randomly divided into 3 groups: the control (n = 17), postnatal day 10 lipopolysaccharide (PND10LPS) (n = 31), and PND25LPS (n = 16) groups, which received intraperitoneal injections of LPS (100 μg/kg) or saline (injection volume: ≤0.

Prenatal undernutrition suppresses sexual behavior in female rats.

Infectious, psychological and metabolic stresses in the prenatal and early neonatal period induce long-lasting effects in physiological function and increase the risk of metabolic disorders later in life. We examined the sexual behavior of female rats that were subjected to undernutrition in the prenatal period. Eight pregnant rats were divided into two groups: a maternal normal nutrition group (mNN; n = 4) and a maternal undernutrition group (mUN; n = 4), which received 50% of the daily food intake amount of the mNN group from gestation day 13 to delivery.

Prenatal undernutrition affects the phenotypes of PCOS model rats.

Although polycystic ovary syndrome (PCOS) is among the most common endocrine disorders in women of reproductive age, its etiology remains poorly understood. From the perspective of developmental origins of health and disease, some studies have investigated the relationship between low birth weight and the prevalence of PCOS and/or PCOS phenotypes in humans; however, the results of these studies were inconclusive. Here, we evaluated the effects of prenatal undernutrition on the metabolic and reproductive phenotypes of dihydrotestosterone-induced PCOS model rats.

Pilot study of the optimal protocol of low dose step-up follicle stimulating hormone therapy for infertile women.

Purpose: To evaluate the optimized protocol of low dose follicle-stimulating hormone (FSH) therapy that has a starting dose of 50 IU/62.5 IU with a small increment dose (12.5 IU) for women with World Health Organization (WHO) II ovulatory disorder and unexplained infertility.

Effects of Low Energy Availability on Reproductive Functions and Their Underlying Neuroendocrine Mechanisms.

It is known that metabolic disturbances suppress reproductive functions in females. The mechanisms underlying metabolic and nutritional effects on reproductive functions have been established based on a large body of clinical and experimental data. From the 1980s to 1990s, it was revealed that disrupted gonadotropin-releasing hormone (GnRH) secretion is the main cause of reproductive impairments in metabolic and nutritional disorders.

Neurokinin B receptor agonist and Dynorphin receptor antagonist stimulated luteinizing hormone secretion in fasted male rodents.

Kisspeptin/neurokinin B (NKB)/dynorphin (Dyn) (KNDy) neuron in hypothalamic arcuate nucleus plays a key role in GnRH/LH pulsatile secretion. We aimed to determine whether stimulation of NKB/neurokinin 3 receptor (NK3R) signaling and inhibition of Dyn/kappa-opioid receptor (KOR) signaling recover LH secretion that is suppressed by acute fasting in male rats. Furthermore, we determined dose dependent effect of NKB/NK3R signaling on serum LH level under acute fasting condition in male mice.

Prenatal undernutrition disrupted the sexual maturation, but not the sexual behavior, in male rats.

Purpose: Exposure to various stressors, including psychological, metabolic, and immune, in the perinatal period induces long-lasting effects in physiological function and increase the risk of metabolic disorders in later life. In the present study, sexual maturation and sexual behavior were assessed in prenatally undernourished mature male rats.

Methods: All the pregnant rats were divided into the maternal normal nutrition (mNN) group and the maternal undernutrition (mUN) group.

Clinical outcome of various metformin treatments for women with polycystic ovary syndrome.

Aim: Polycystic ovary syndrome (PCOS) is an ovulatory disorder and insulin resistance and diabetes are involved in its pathophysiology. Metformin, an anti-diabetic agent, has been reported to be useful to induce ovulation.

Methods: Metformin treatment was classified into four types: (1) clomiphene-metformin combination treatment for clomiphene-resistant patients; (2) clomiphene-metformin combination for clomiphene-sensitive patients; (3) clomiphene-metformin combination for naïve patients; and (4) metformin monotherapy.

The effects of chronic testosterone administration on hypothalamic gonadotropin-releasing hormone regulatory factors (Kiss1, NKB, pDyn and RFRP) and their receptors in female rats.

The effects of androgens on gonadotropin-releasing hormone (GnRH) secretion in females have not been fully established. To clarify the direct effects of androgens on hypothalamic reproductive factors, we evaluated the effects of chronic testosterone administration on hypothalamic GnRH regulatory factors in ovariectomized (OVX) female rats. Both testosterone and estradiol reduced the serum luteinizing hormone levels of OVX female rats, indicating that, as has been found for estrogen, testosterone suppresses GnRH secretion via negative feedback.

The effects of chronic testosterone administration on body weight, food intake, and adipose tissue are changed by estrogen treatment in female rats.

In females, estrogens play pivotal roles in preventing excess body weight (BW) gain. On the other hand, the roles of androgens in female BW, appetite, and energy metabolism have not been fully examined. We hypothesized that androgens' effects on food intake (FI) and BW regulation change according to the estrogens' levels.

Relationship between serum anti-Mullerian hormone and clinical parameters in polycystic ovary syndrome.

Polycystic ovary syndrome (PCOS) is an ovulatory disorder that affects 6-10% of women of reproductive age. Serum AMH level may be an additional factor, or surrogate of PCOM, in the diagnostic criteria of PCOS. We evaluated the correlations between the serum AMH level and various endocrine and metabolic features in PCOS using the latest fully automated assay.

Kisspeptin mRNA expression is increased in the posterior hypothalamus in the rat model of polycystic ovary syndrome.

Hypersecretion of luteinizing hormone (LH) is a common endocrinological finding of polycystic ovary syndrome (PCOS). This derangement might have a close relationship with hypothalamic kisspeptin expression that is thought to be a key regulator of gonadotropin-releasing hormone (GnRH). We evaluated the relationship between the hypothalamic-pituitary-gonadal axis (HPG axis) and kisspeptin using a rat model of PCOS induced by letrozole.