111 research outputs found
A Novel Concept of Fundus-Ovary-Salpinx-Para-Aorta Implantation Promoting Unit during Human Embryo Implantation
Human embryo implantation is mainly regulated by the endocrine system. Since the ovary, fallopian tube, and fundus can directly communicate through the mesosalpinx and ovarian ligament, the local concentration of progesterone in the pathway of the developing embryo is considered to be higher than in systemic blood circulation. The immune system promotes embryo implantation by stimulating progesterone production of the ovary and by inducing endometrial differentiation. The recognition of the developing embryo in the fallopian tube by the immune system is achieved through the para-aortic lymph nodes. On the basis of the above evidence, the autologous immune cells activated in vitro were demonstrated to improve clinical pregnancy rates in patients with repeated implantation failures. In addition, the autonomic nerve system that innervates the fundus, the ovary, and the fallopian tube from the para-aortic region is proposed to regulate the environment of the pathway of the developing embryo. From these findings, we suppose that a unique unilateral functional unit to promote human embryo implantation exists in the pathway of the developing embryo including the para-aortic regions and propose naming this novel functional unit the Fundus-Ovary-Salpinx-Para-aorta Implantation Promoting unit (FOSPa-IP unit)
Dual Positive Regulation of Embryo Implantation by Endocrine and Immune Systems - Step-by-Step Maternal Recognition of the Developing Embryo
In humans, HCG secreted from the implanting embryo stimulates progesterone production of the corpus luteum to maintain embryo implantation. Along with this endocrine system, current evidence suggests that the maternal immune system positively contributes to the embryo implantation. In mice, immune cells that have been sensitized with seminal fluid and then the developing embryo induce endometrial differentiation and promote embryo implantation. After hatching, HCG activates regulatory T and B cells through LH/HCG receptors and then stimulates uterine NK cells and monocytes through sugar chain receptors, to promote and maintain pregnancy. In accordance with the above, the intrauterine administration of HCG-treated PBMC was demonstrated to improve implantation rates in women with repeated implantation failures. These findings suggest that the maternal immune system undergoes functional changes by recognizing the developing embryos in a stepwise manner even from a pre-fertilization stage and facilitates embryo implantation in cooperation with the endocrine system. © 2016 John Wiley & Sons A/S.Embargo Period 12 month
Presence of Transcription Factor OCT4 Limits Interferon-tau Expression during the Pre-attachment Period in Sheep
Interferon-tau (IFNT) is thought to be the conceptus protein that signals maternal recognition of pregnancy in ruminants. We and others have observed that OCT4 expression persists in the trophectoderm of ruminants; thus, both CDX2 and OCT4 coexist during the early stages of conceptus development. The aim of this study was to examine the effect of CDX2 and OCT4 on IFNT gene transcription when evaluated with other transcription factors. Human choriocarcinoma JEG-3 cells were cotransfected with an ovine IFNT (-654-bp)-luciferase reporter (-654-IFNT-Luc) construct and several transcription factor expression plasmids. Cotransfection of the reporter construct with Cdx2, Ets2 and Jun increased transcription of -654-IFNT-Luc by about 12-fold compared with transfection of the construct alone. When cells were initially transfected with Oct4 (0 h) followed by transfection with Cdx2, Ets2 and/or Jun 24 h later, the expression of -654-IFNT-Luc was reduced to control levels. OCT4 also inhibited the stimulatory activity of CDX2 alone, but not when CDX2 was combined with JUN and/or ETS2. Thus, when combined with the other transcription factors, OCT4 exhibited little inhibitory activity towards CDX2. An inhibitor of the transcriptional coactivator CREB binding protein (CREBBP), 12S E1A, reduced CDX2/ETS2/JUN stimulated -654-IFNT-Luc expression by about 40%, indicating that the formation of an appropriate transcription factor complex is required for maximum expression. In conclusion, the presence of OCT4 may initially minimize IFNT expression; however, as elongation proceeds, the increasing expression of CDX2 and formation of the transcription complex leads to greatly increased IFNT expression, resulting in pregnancy establishment in ruminants
INFLUENCE OF DIETARY ENERGY ON ENDOCRINE MECHANISMS CONTROLLING REPRODUCTIVE FUNCTIONS IN THE BOVINE FEMALE
A series of experiments was conducted to elucidate endocrine mechanisms responsible for controlling reproductive functions in estrual and nutritional anestrous beef heifers. In experiment 1, the feedback mechanisms of ovarian steroids in controlling luteinizing hormone (LH) secretion during the follicular phase of the bovine estrous cycle were studied. Serum LH and 17(beta)-estradiol (E(,2)) increased linearly (P \u3c 0.01) whereas no change in amplitude of LH pulses was detected before the preovulatory LH surge. In experiment 2, 12 cross-bred heifers were used to determine patterns of body weight changes in heifers fed diets varying in energy, and to relate these findings to changes in concentrations and secretory patterns of reproductive hormones. At the time heifers fed a diet limited in energy stabilized body weight after rapid weight loss while heifers fed a diet high in energy did not gain body weight, body weight changes positively affected (P \u3c 0.001) mean concentrations of LH during the follicular and subsequent luteal phases of the estrous cycle. Serum concentrations of progesterone and E(,2) were not related to weight changes. During the latter part of the weight stabilization phase in heifers fed the diet restricted in energy while heifers fed the diet high in energy gained body weight, however, body weight changes had a lesser influence (P \u3c 0.05) on concentrations of LH. Serum progesterone and E(,2) concentrations were positively related to body weight changes at this time. In experiment 3, effects of dietary energy restriction and E(,2) on LH secretions were studied using untreated ovariectomized and E(,2) treated ovariectomized heifers. Frequencies of LH pulses in untreated ovariectomized heifers fed the low energy (L) diet were lower (P \u3c 0.01) than in heifers fed the high energy (H) diet. Amplitudes of LH pulses in heifers fed the L diet were higher (P \u3c 0.01) than in heifers fed the H diet. Pulses and mean concentrations of LH were suppressed (P \u3c 0.01) in E(,2) treated ovariectomized heifers fed the L diet long before nutritional anestrus was induced. In experiment 4, endocrine mechanisms during restoration of estrous cycles following nutritional anestrus were studied. Estradiol suppressed (P \u3c 0.01) LH secretion in E(,2) treated ovariectomized heifers during the period of estrual restoration from nutritional anestrus in intact heifers. Suppressive effects of E(,2) on LH secretion continued in E(,2) treated ovariectomized heifers after intact heifers resumed estrous cycles
INFLUENCE OF DIETARY ENERGY ON ENDOCRINE MECHANISMS CONTROLLING REPRODUCTIVE FUNCTIONS IN THE BOVINE FEMALE
A series of experiments was conducted to elucidate endocrine mechanisms responsible for controlling reproductive functions in estrual and nutritional anestrous beef heifers. In experiment 1, the feedback mechanisms of ovarian steroids in controlling luteinizing hormone (LH) secretion during the follicular phase of the bovine estrous cycle were studied. Serum LH and 17(beta)-estradiol (E(,2)) increased linearly (P \u3c 0.01) whereas no change in amplitude of LH pulses was detected before the preovulatory LH surge. In experiment 2, 12 cross-bred heifers were used to determine patterns of body weight changes in heifers fed diets varying in energy, and to relate these findings to changes in concentrations and secretory patterns of reproductive hormones. At the time heifers fed a diet limited in energy stabilized body weight after rapid weight loss while heifers fed a diet high in energy did not gain body weight, body weight changes positively affected (P \u3c 0.001) mean concentrations of LH during the follicular and subsequent luteal phases of the estrous cycle. Serum concentrations of progesterone and E(,2) were not related to weight changes. During the latter part of the weight stabilization phase in heifers fed the diet restricted in energy while heifers fed the diet high in energy gained body weight, however, body weight changes had a lesser influence (P \u3c 0.05) on concentrations of LH. Serum progesterone and E(,2) concentrations were positively related to body weight changes at this time. In experiment 3, effects of dietary energy restriction and E(,2) on LH secretions were studied using untreated ovariectomized and E(,2) treated ovariectomized heifers. Frequencies of LH pulses in untreated ovariectomized heifers fed the low energy (L) diet were lower (P \u3c 0.01) than in heifers fed the high energy (H) diet. Amplitudes of LH pulses in heifers fed the L diet were higher (P \u3c 0.01) than in heifers fed the H diet. Pulses and mean concentrations of LH were suppressed (P \u3c 0.01) in E(,2) treated ovariectomized heifers fed the L diet long before nutritional anestrus was induced. In experiment 4, endocrine mechanisms during restoration of estrous cycles following nutritional anestrus were studied. Estradiol suppressed (P \u3c 0.01) LH secretion in E(,2) treated ovariectomized heifers during the period of estrual restoration from nutritional anestrus in intact heifers. Suppressive effects of E(,2) on LH secretion continued in E(,2) treated ovariectomized heifers after intact heifers resumed estrous cycles
Expression and Potential Role of GATA Factors in Trophoblast Development
Despite exhaustive studies, molecular mechanisms governing blastocyst formation, implantation to the uterine endometrium and placentation have not been definitively characterized. GATA family proteins are a group of zinc finger transcription factors, for which gene ablations eventually result in embryonic death later in pregnancy. These findings suggested that GATA factors are not essential for early embryonic development. However, recent studies from our laboratory and others have revealed that GATA proteins are involved in the regulation of key genes expressed by the trophectoderm that underpin the transition from the morula to trophoblast, and trophectoderm maintenance. Consequently, it is important to consider the current understanding how GATA factors govern early trophectoderm development
Long Term Selection for Small Body Weight in Japanese Quail I : Direct Selection Response from 60 to 65th Generations
It is important to know the limit of artificial selection for efficient animal production. The aim of this research was to examine whether the selection for small body weight in Japanese quail has reached to the limit after the long term selection over 65 generations. In this research, two lines, SS and RR were compared. RR line was produced by random mating in a closed population as the control, and SS line was selected for small body weight at 6 weeks of age until 65 generations. Additionally, the data of LL line selected for large body weight was used to evaluate a selection limit in SS line though the details were not shown. Each line was composed of about 30 pair-matings, and body weight measurement was performed every week until 6 weeks of age, but the body weights of candidate birds selected for production of next generation were measured until 15 weeks of age. In the first step of selection, 4 males and 4 females were selected as a general rule among the offspring from each pair-mating at about 4 weeks of age. In the second step of selection, one male and one female were chosen by body weight at 6 weeks of age from 8 individuals selected in the first step, and 30 pari-matings were arranged with the individuals having no consanguineous relation in the preceding 4 generations. Mean body weight of SS line during 60-65 generations was 59.5g and that of RR line was 106.5 g, and the difference was significant (P<0.01). Selection pressure (SP) in the two lines was constant throughout the generations. Selection intensity (SI) in SS line was in the negative direction, and that in RR line was near zero. Estimated heritability in the two lines was variable from generation to generation. Realized heritabilities in SS line increased in both males and females during two terms of 54 to 59 and 60 to 65 generations. The selection response increased in the negative direction in response to cumulative selection differential. The observed ratio of mean body weight at 6 weeks of age in SS line to that in LL line (ORM) and observed ratio of difference between mean body weight at the same age in SS line and that in LL line to the standard deviation of body weight in RR line (OR) suggested that selection limit may not have been reached in SS line after the long term selection for 65 generations and it may be possible to expect further genetic improvement. Generally, artificial selection during a very long period would reach to a limit on account of decrease in genetic diversity. However, selection in the direction for small body weight was found to show the different tendency from the selection for large body weight. Miniaturization of body size is an interesting biological phenomenon from the evolutionary point of view. The SS line established in the present study would be useful for the research from molecular biologic and metabolic aspects to have an insight into evolutionary mechanism of miniaturization
Successful pregnancy and live birth from a hypogonadotropic hypogonadism woman with low serum estradiol concentrations despite numerous oocyte maturations: a case report
Abstract Background The increase in serum estradiol (E2) concentrations during the follicular phase becomes the index of oocyte maturation in vivo. When ovarian stimulation is performed to hypogonadotropic hypogonadism (HH) patients with only follicle stimulating hormone (FSH), proper increase in serum E2 concentrations is not observed. Even if oocytes are obtained, which usually have low fertilization rate. In this report, we would like to present an unique case, in which under low E2 concentrations and without luteinizing hormone (LH) administration, numerous mature oocytes could be obtained and a healthy baby delivered. Case presentation During controlled ovarian stimulation (COS) with only recombinant follicular stimulating hormone (rFSH) administrations, a 26-year-old Japanese woman with hypothalamic amenorrhea (i.e., hypogonadotropic hypogonadism) developed numerous follicles despite low serum E2, 701 pg/ml, and high progesterone (P4) concentrations, 2.11 ng/ml, on the day of induced ovulation. However, 33 cumulus-oocyte complexes (COCs) were successfully obtained; following the embryo culture, four early embryos and six blastocysts were cryopreserved. This patient received hormone replacement therapy (HRT), during which one of six cryopreserved blastocysts was thawed and transferred into the uterine lumen. The patient became pregnant from the first transfer, went through her pregnancy without any complications, and delivered a healthy male baby in the 39th week. Low E2 concentrations in follicular fluids (FFs) are suggestive that aromatase and/or 17β-hydroxysteroid dehydrogenase (17β-HSD) could be low. Conclusions Serum E2 concentrations may not be the most important index for oocyte maturation during COS, and suggested that oocyte maturation was in progress even under low serum E2 and high P4 conditions. Even if serum E2 concentrations did not properly increase, numerous mature oocytes could be obtained, resulting in the birth of a healthy baby
Different Levels of Ovine Interferon-t Gene Expressions Are Regulated Through the Short Promoter Region Including Ets-2 Binding Site
Regulation of interferon-t (IFNt) production, a conceptus secretory protein implicated in the process of maternal recognition of pregnancy, has not been fully elucidated. Among more than 10 ovine IFNt (oIFNt) gene sequences characterized, approximately 75% of oIFNt transcripts expressed in utero is derived from oIFNt-o10 gene and amounts of transcripts from other oIFNt genes such as oIFNt-o8 or oIFNt-o2 are minimal. It was hypothesized that the variation in expression levels exhibited by oIFNt-o10 and oIFNt-o8/-o2 genes was due to differences in the proximal promoter regions of these oIFNt genes. To test this hypothesis, transient transfection experiments with human choriocarcinoma JEG3 cells were executed with deleted and/or mutated 50-upstream regions of these oIFNt genes attached to the chloramphenicol acetyltransferase (CAT) reporter gene. Because only the Ets-2 binding site located in the oIFNt-o10 gene appeared to differentiate the expression levels of these constructs, the 6 base pair (bp) Ets-2 sequence from the oIFNt-o10 gene inserted into the oIFNt-o8/-o2 gene-reporter construct was examined. The insertion of this Ets-2 binding site into the oIFNt-o8/o2-reporter construct failed to increase the degree of transactivation. Rather than this 6 bp sequence, a 22 bp sequence of the proximal promoter region, including the Ets-2 binding site, of the oIFNt-o10 gene was required for oIFNt-o8/-o2-reporter transactivation. By electrophoretic mobility shift assay (EMSA), nuclear protein(s) bound to this 22 bp from the oIFNt-o10 and oIFNt-o8/o2 genes differed. These results suggest that the short promoter region including the Ets-2 binding site, not the Ets-2 binding region itself, may determine different levels of oIFNt gene expressions seen in utero
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