Activin A promotes the development of endometriotic lesions in a murine model of endometriosis, and the immunohistochemical localization of phosphorylated suppressor of mothers against ...decapentaplegic homolog 2/3 (pSMAD2/3) complex in endometriotic lesions has been reported. Activin may therefore be involved in the development and proliferation of endometriotic cells via the SMAD signaling pathway. However, few detailed reports exist on SMAD7 expression in endometriosis. The purpose of this study was to investigate the expression of pSMAD2/3 or pSMAD3 and SMAD7 in the orthotopic human endometrium, ovarian endometriosis, and endometriotic lesions in a murine model and the effect of activin A on pSMAD2/3 and SMAD7 expression. We established an endometriosis murine model via the intraperitoneal administration of endometrial tissue and blood from donor mice. Activin A was intraperitoneally administered to the activin group. We immunohistochemically evaluated orthotopic endometria, ovarian endometriotic tissues, and endometriotic lesions in the murine model followed by western blotting. We found that pSMAD3 and SMAD7 were expressed in ovarian endometriosis and orthotopic endometria from patients with and without endometriosis. In the murine model, endometriotic lesions expressed pSMAD2/3 and SMAD7 in the activin and control groups, and higher SMAD7 expression was found in the activin group. To the best of our knowledge, this study is the first to show that SMAD7 expression is upregulated in endometriosis. In conclusion, these results suggest that activin A activates the SMAD signaling pathway and promotes the development of endometriotic lesions, thus identifying SMAD7 as a potential therapeutic target for endometriosis.
Oxytocin (OT) affects many behavioral, psychological, and physiological functions, including appetite and body weight regulation. Central and peripheral OT levels are markedly affected by gonadal ...steroids, especially estrogen, and the anorectic effects of estrogen are partially mediated by OT in rodents. In this study, the relationship between the estrogen milieu and serum OT levels was evaluated in women of reproductive age under physiological (
= 9) and supraphysiological estrogenic conditions (
= 7). Consequently, it was found that serum OT levels were increased in physiological (the ovulatory phase) and supraphysiological (on the day of the human chorionic gonadotropin trigger in an ovarian stimulation cycle) estrogenic conditions, and that serum OT levels were positively correlated with serum estradiol levels. On the other hand, serum OT levels were negatively correlated with serum progesterone levels, and there was no correlation between serum and follicular OT levels. These results suggest that OT levels may be positively and negatively regulated by estrogen and progesterone, respectively, in humans. However, the physiological roles of these actions of gonadal steroids on OT remain unclear.
In recent years, the effects of androgens on metabolic and body weight regulation systems and their underlying mechanisms have been gradually revealed in females. In women and experimental animals of ...reproductive age, androgen excess can adversely affect metabolic functioning, appetite, and body weight regulation. In addition, excess androgens can increase the risk of metabolic disorders, such as obesity, insulin resistance, and diabetes. These unfavorable effects of androgens are induced by alterations in the actions of hypothalamic appetite-regulatory factors, reductions in energy expenditure, insulin resistance in skeletal muscle, and β-cell dysfunction. Interestingly, these unfavorable effects of androgens on metabolic and body-weight regulation systems are neither observed nor evident in ovariectomized animals and post-menopausal women, indicating that the adverse effects of androgens might be dependent on the estrogen milieu. Recent findings may provide novel sex- and age-specific strategies for treating metabolic diseases.
Kisspeptin, which is the product of the kiss1 gene and its receptor kiss1r, have emerged as the essential gatekeepers of reproduction. The present study used gonadally intact female rats to evaluate ...fasting-induced suppression of the KiSS-1 system of anteroventral periventricular nucleus (AVPV) and arcuate nucleus (ARC) under normal physiological conditions. Starting on the day of estrous, one group of rats was subjected to 72 h of food deprivation, while the other group of rats was able to continue feeding ad libitum. The length of the estrous cycle was significantly longer in the food-deprived rats as compared to the feeding rats. At the end of the 72-h food deprivation period, all of the food-deprived rats were at the diestrous phase, with their serum concentrations of LH and leptin significantly lower than that observed in the feeding rats. In addition, as compared to the feeding rats, the expression levels of kiss1 mRNA were significantly lower in the food-deprived rats in the posterior hypothalamic block, which contained the ARC, but not in the anterior hypothalamic block, which contain the AVPV. However, both the kiss1r mRNA expression levels in the anterior and posterior hypothalamic blocks and the neurokinin B and neurokinin 3 receptor mRNA expression levels in the posterior hypothalamic block were not significantly different between the feeding and food-deprived rats. Thus, lower kiss1 mRNA levels in the ARC appear to be responsible for the fasting-induced inhibition of gonadotrophin secretion and subsequent prolongation of the estrous cycle.
The COVID-19 pandemic has profoundly changed medical student clinical practice and limited hospital clinical practice. In order to make student training more meaningful, we have introduced medical ...education using a laparoscopic simulator. We conducted a student questionnaire on the usefulness of this training and evaluated the degree of understanding. For students who were able to practice at the hospital, they practiced using a laparoscopic simulator （Lap Mentor™）. A questionnaire survey was conducted on the presence or absence of interest in surgery. Student understanding of laparoscopic surgery improved 100％. 91％ understood the surgical procedure, 91％ improved technique and 97％ understood pelvic anatomy. In the training at Lap Mentor™, medical students were able to experience surgery while viewing images of the inside of the pelvis, which served as a means to increase their interest in surgery and obstetrics and gynecology.
•We investigated the effects of ovariectomy on immune response.•Ovariectomized (OVX) female rats showed enhanced anorectic response to LPS.•Cytokine responses to LPS are elevated, especially in ...hypothalamus, in OVX rats.•Immune responses may be changed after menopause.
Obesity leads to increases in inflammatory responses in a site-specific manner. Ovariectomized animals, usually used as menopause models, exhibit obesity; however, their inflammatory responses have not been fully examined. In the present study, we investigated whether ovariectomy had site-specific effects on inflammatory responses. First, fever and anorectic responses to systemic injections of lipopolysaccharide (LPS) (500μg/kg, i.p.) were compared between ovariectomized rats (OVX) and sham-operated female rats (Sham). Inflammatory cytokines at the central and peripheral levels were also compared under saline-injected and LPS-injected conditions. Body weight in OVX was significantly higher than in Sham. The anorectic responses (reduction of body weight and food intake) to LPS were higher in OVX than in Sham. In the hypothalamus, all of the examined cytokine (IL-1β, TNF-α and IL-6) mRNA levels in OVX were higher than in Sham under the LPS-injected condition. On the other hand, in serum and adipose tissue, only IL-6, not IL-1β and TNF-α, levels in OVX were significantly higher than those in Sham under the LPS-injected condition. Second, responses to central (intracerebroventricular) injections of LPS (500ng) were compared between OVX and Sham. The result was that the fever response in OVX was more evident than in Sham. Finally, responses to systemic injections of LPS (500μg/kg, i.p.) were compared between OVX (OVX-oil) and OVX with estradiol (E) and progesterone (P) supplementation (OVX-EP). The anorectic responses and hypothalamic cytokine mRNA levels under LPS-injected condition were not different between OVX-oil and OVX-EP. These results indicate that ovariectomy enhances inflammatory responses, especially at the central level compared with the peripheral level. As supplementation of E and P could not attenuate the anorectic and cytokine responses to LPS, the deficiency of gonadal steroids might not be directly involved in the increase of inflammatory responses in OVX.
► Postnatal period. ► Change mRNA and peptide of RFRP. ► mRNA of RFRP is increased by estradiol.
The mammalian gonadotropin-inhibitory hormone (GnIH) ortholog RFamide-related peptide (RFRP) is ...considered to act on gonadotropin-releasing hormone (GnRH) neurons and on the pituitary to inhibit gonadotropin release and synthesis. To understand the functional significance of this neuropeptide, we investigated the physiological changes in RFRP at mRNA and peptide levels, as well as at the mRNA level of its cognate receptor, G protein-coupled receptor 147 (
GPR147), in the rat hypothalamus during development. We also investigated the effects of gonadal steroids on mRNA expression levels of these molecules. In male rats, mRNA expressions of both
RFRP and
GPR147 increased from postnatal days 12 and 16, peaking at postnatal days 35 and 42, respectively. However, their expressions fell at postnatal day 49. In female rats, mRNA expression of
RFRP continued to increase throughout development; mRNA expression of
GPR147 in female rats increased from postnatal day 16, peaking at postnatal day 28, but decreased from postnatal day 35. The hypothalamic contents of RFRP on postnatal days 28 and 42 were significantly higher than on postnatal day 4 in male rats, and those on postnatal day 42 were significantly higher than those on postnatal days 4 and 28 in females. Neither orchidectomy nor ovariectomy influenced mRNA expression levels of
RFRP or
GPR147 in the prepubertal period when endogenous sex steroid levels were low in males and females. Administration of estradiol-17β (E2) increased mRNA expression of
RFRP in prepubertal females. These results suggest that the hypothalamic RFRP system changes during development. An ovarian sex steroid, E2, may stimulate mRNA expression of
RFRP in the prepubertal period when the basal E2 concentration is low.
Polycystic ovary syndrome (PCOS) is associated with an increased risk of psychological distress as well as enhanced responses to psychosocial stress. Recently, it was hypothesized that PCOS patients ...may be at high risk of novel COVID-19 infections and worse clinical presentations during such infections. Here, we evaluated the effects of PCOS on stress responses to bacterial and viral mimetics using dihydrotestosterone-induced PCOS model rats. Lipopolysaccharide (LPS; a bacterial mimetic) or polyinosinic-polycytidylic acid (Poly-IC; a viral mimetic) was injected into PCOS model rats (PCOS) and non-PCOS rats (control), and the rats' stress responses were evaluated. In the PCOS group, the rats’ anorectic and febrile responses to LPS injection were enhanced, whereas their anorectic and febrile responses to Poly-IC injection were unaltered. The PCOS group also exhibited greater changes in peripheral cytokine levels in response to LPS, but not Poly-IC. On the contrary, after the injection of Poly-IC depressed locomotor activity was more evident in the PCOS group, whereas no such changes were observed after LPS injection. These findings indicate that although the stress responses of PCOS model rats to infection may be enhanced, the patterns of change in stress responses and their underlying mechanisms may differ between bacterial and viral infections.
•Responses to psychosocial stress are increased in PCOS.•Responses to bacterial and viral mimetics were evaluated in PCOS model rats.•Responses to LPS and Poly-IC were increased in PCOS model rats.•The patterns of these stress responses to LPS and Poly-IC were different.
Decreased activity of kisspeptin, the product of the hypothalamic Kiss1 gene, is the major cause of the suppression of reproductive function in subnutritional conditions. The sensitivities of the ...endocrine and the hypothalamic neuronal systems to nutritional status develop during the neonatal period. We examined the developmental changes in the sensitivity of hypothalamic mRNA expression of Kiss1 and its receptor, Kiss1r, to nutritional status in female rats. Kiss1 mRNA expression was reduced by 24 h food deprivation (24 h FD) at postnatal day 25, but not at postnatal day 5 or 15. Kiss1r mRNA expression was reduced by the 12 or 24 h FD at postnatal days 5 and 25, but not at postnatal day 15. Kiss1r mRNA level was found to be correlated with the plasma leptin level, and the administration of leptin, which increased the serum leptin concentration above the physiological range, restored the acute FD-induced suppression of Kiss1r mRNA expression. These data suggest that the hypothalamic Kiss1 and Kiss1r mRNA expression is differentially affected by the nutritional condition at different age points. It is speculated that the sensitivity of Kiss1 mRNA, which is expressed in kisspeptin neuron, to nutritional status develops during the neonatal period. On the other hand, it seems that the sensitivity of Kiss1r mRNA, which is expressed in GnRH neuron, to nutritional status has been already established during the early neonatal period. These data also show that hypoleptinemia plays a role in the reduction of hypothalamic Kiss1r mRNA expression under subnutritional conditions.
► We study effect of prepubertal exposure to glucocorticoid on female rats’ puberty. ► Prepubertal exposure to glucocortiocid delays puberty in female rats. ► Delayed onset of puberty occurs ...independent of Kiss1-GnRH system.
Secretion of glucocorticoids is widely known as a key endocrine response to stresses. Prenatal dexamethasone administration induces intrauterine growth retardation and delayed onset of puberty in female rats independent of the hypothalamic Kiss1-gonadotropin-releasing hormone (GnRH) system. The aim of this study was to evaluate the influence of chronic intracerebroventricular (central, CD) or subcutaneous (peripheral, PD) dexamethasone administration to prepubertal female rats on the onset of puberty and body weight change. Rats administered dexamethasone from day 25 to day 34 (CD and PD) showed significantly reduced body weight gain throughout the experimental period and delayed onset of vaginal opening compared with rats administered saline centrally (CS) or peripherally (PS). At 34 days old, hypothalamic Kiss1r mRNA levels were significantly lower with CD than with CS. No significant differences were seen between rats administered saline and rats administered dexamethasone with regard to hypothalamic Kiss1, GnRH and NPY mRNA levels or serum LH levels. Serum leptin concentrations were higher in CD and PD than in the controls (CS and PS). These results suggest that the delayed onset of puberty induced by prepubertal dexamethasone administration occurs independent of the hypothalamic Kiss1-GnRH system.
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