• Development and Reproduction
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• v.4 no.1
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• pp.61-66
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• 2000

This study was investigated to analyze the inactivating point mutation and expression level of follicle-stimulating hormone(FSH) receptor mRNA. In first experiment, we analyzed the point mutation. Peripheral blood was collected from each patient. To screen individuals for the C566T mutation, PCR was performed for exon 7 of the FSH receptor gene in 10 patients. No inactivating point mutation of FSH receptor gene was identified in women with premature ovarian failure. To analyze the expression level of FSH receptor, mRNA expressions were examined by RT-PCR method using specific primers for the FSH receptor. The amount of FSH receptor mRNA expressed in POF patients was lower than that in the control group. But it was not significantly different. These finding suggests that lower expression of FSH receptor in premature ovarian failure patients might be the cause of the low response to the gonadotropin during the hyperstimulation in IVF-ET cycles.

• Clinical and Experimental Reproductive Medicine
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• v.35 no.1
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• pp.69-76
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• 2008

Objective: The purposes of this study were to determine the distribution of follicle-stimulating hormone receptor (FSHR) genotypes in infertile Korean women and to evaluate the relationship between FSHR genotypes and clinical outcomes of IVF-ET cycles. Methods: Genomic DNA was extracted from peripheral blood in 1, 020 of infertile Korean women. Genotypes of FSHR at Thr307Ala (T/A) and Asn680Ser (N/S) were screened by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis. Clinical outcomes related to the genotypes of FSHR were evaluated in IVF-ET cycles (n=302) with controlled ovarian hyperstimulation (COH) of infertile women under 40 years old. Results: In a population of 1, 020 infertile Korean women, the frequency of TT/NN, TA/NS and AA/SS for the major variant Thr307Ala and Asn680Ser was 44.80%, 41.96% and 10.49%, respectively. There was no significant difference in characteristics of ovarian response and clinical pregnancy rate among the major genotypes of FSHR in IVF-ET cycles with COH. However, implantation rate of AA/SS patients was significantly higher than that of TT/NN patients (24.5% vs 15.7%, p<0.05). Conclusion: This study showed that FSHR genotype was not directly associated with ovarian response in IVF-ET cycles with COH. The relationship between clinical outcomes and FSHR genotypes of patients should be substantiated by further studies.

• Korean Journal of Animal Reproduction
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• v.23 no.4
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• pp.347-352
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• 1999

This cDNAs were cloned with the aid of the polymerase chain reaction (PCR) by sequences based on cloned rat LH/CG and FSH receptor cDNAs. A cDNAs of LHR and FSHR were transfected into the 293 cells. Several clonal cell lines were obtained expressing different numbers of cell surface receptors. One cell lines for each LHR and FSHR were chosen, and a corresponding cell lines expressing the wild type LHR and FSHR were selected based on the number of cell surface receptor for the particular LHR and FSHR. The abilities of the LHR and FSHR to transduce the hCG and FSH signals were measured by quantitating cAMP accumulation in cells incubated with increasing concentrations of hCG and FSH. The cAMP accumulation effects for these receptors were increased by the increasing concentrations of hCG and FSH. Thus, most of the receptors expressed in cells transfected with LHR and FSHR could be detected by measuring hormone binding and cAMP response, and can utilize to study the structure function and signal transduction of the choriogonadotropins and glycoprotein hormones.

• Korean Journal of Animal Reproduction
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• v.24 no.2
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• pp.125-142
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• 2000

13). Analysis of a purified preparation of eCG revealed that its $\beta$ -subunit consists of 149 amino acids, which was confirmed by the molecular cloning of its cDNA. There seem to be at least four to six, or even as many as 11, O-glycosylation sites on the extended C-tenninal region of the eCG $\beta$-subunit. Interestingly, eCG is a unique member of this family, as it appear to be a single molecule that possesses both LH- and FSH-like activities. Using the cDNA prepared from mRNA extracted from equine placental and pituitary tissues, we cloned the cDNA of eCG $\alpha$- and $\beta$ -subunits and eFSH $\beta$ -subunit. The mRNA expression of each subunit seems to be independently regulated, which may account for differences in the quantities of $\alpha$ - and $\beta$ -subunits in the placenta and pituitary. Thus, eCG is a distinct molecule from the view points of its biological function and glycoresidue structures. Recombinant eCGs including the mutants which lack oligosaccharides will be useful tools for analyzing the structure-function relationships of gonadotropins in the horse as well as other species. Similar experiments will also clarify the proposed structure and biological functions for the glycoprotein hormones. These experimental are now possible, and hopefully a resolution of the existing controversy will be forthcoming in the near future.

• Development and Reproduction
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• v.11 no.1
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• pp.13-20
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• 2007

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.

• Korean Journal of Animal Reproduction
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• v.26 no.3
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• pp.299-308
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• 2002

In horse, a single gene encodes both eCG and eLH $\beta$ subunits. The difference between eCG and eLH lies in the structure of their glycoresidues, which are both sialylated and sulfated in LH and sialylated in CG eCG consists of highly glycosyiated $\alpha$- and $\beta$-subunits and is an unique member of the gonadotropin family because it elicits response characteristics of both FSH and LH in other species than the horse. This dual activity of eCG in heterologous species is of fundamental interest to the study of gonadotropin structure-function relationships and the understanding of the molecular bases of the specific interactions of these hormones with their receptors. Thus, eCG is a dintinct molecule from the view points of its biological function and glycoresidue structures. The oligosaccharide at Asn 56 of the $\alpha$-subunit plays an indispensable role, whereas the carboxyl-terminal extension of the eCG $\beta$-subunit with its associated O-linked oligosaccharides is not improtant for, the in vitro LH-like activity of eCG. In contrast, both N- and O-linked oligosaccharides play important roles for FSH-like activity and increase FSH-like activity by removal of N- and O-linked oligosaccharides. Therefore, the dual LH- and FSH-like activities of eCG can be clearly separated by removal of either the N-linked oligosaccharide on the $\alpha$-subunit or CTP-associated O-linked oligosaccharides from its $\beta$-subunit. The glycoresidues seem to play crucial roles fer biological activities. The tethered-eCG was effciently secreted and showed similar LH-like activity to the dimeric eCG $\alpha$/ $\beta$ and native eCG. FSH-like activity of the tethered-eCG was also shown similarly in comparison with the native and wild type eCG $\alpha$/ $\beta$. Our data for the first time suggest that the tethered-eCG can be expressed efficiently and the produced product by the CHO-Kl cells is fully LH- and FSH-like activities in rat in vitro bioassay system. Our results also suggest that this molecular can imply particular models ot FSH-like activity not LH-like activity in the eCG. Taken together, these data indicate that the constructs of tethered molecule will be useful in the study of mutants that affect subunit association and/or secretion.

• Clinical and Experimental Reproductive Medicine
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• v.23 no.3
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• pp.247-268
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• 1996

It has been known for a long time that gonadotropins and steroid hormones play a pivotal role in a series of reproductive biological phenomena including the maturation of ovarian follicles and oocytes, ovulation and implantation, maintenance of pregnancy and fetal growth & development, parturition and mammary development and lactation. Recent investigations, however, have elucidated that in addition to these classic hormones, multiple growth factors also are involved in these phenomena. Most growth factors in reproductive organs mediate the actions of gonadotropins and steroid hormones or synergize with them in an autocrine/paracrine manner. The insulin-like growth factor(IGF) system, which is one of the most actively investigated areas lately in the reproductive organs, has been found to have important roles in a wide gamut of reproductive phenomena. In the present communication, published literature pertaining to the intrauterine IGF system will be reviewed preceded by general information of the IGF system. The IGF family comprises of IGF-I & IGF-II ligands, two types of IGF receptors and six classes of IGF-binding proteins(IGFBPs) that are known to date. IGF-I and IGF-II peptides, which are structurally homologous to proinsulin, possess the insulin-like activity including the stimulatory effect of glucose and amino acid transport. Besides, IGFs as mitogens stimulate cell division, and also play a role in cellular differentiation and functions in a variety of cell lines. IGFs are expressed mainly in the liver and messenchymal cells, and act on almost all types of tissues in an autocrine/paracrine as well as endocrine mode. There are two types of IGF receptors. Type I IGF receptors, which are tyrosine kinase receptors having high-affinity for IGF-I and IGF-II, mediate almost all the IGF actions that are described above. Type II IGF receptors or IGF-II/mannose-6-phosphate receptors have two distinct binding sites; the IGF-II binding site exhibits a high affinity only for IGF-II. The principal role of the type II IGF receptor is to destroy IGF-II by targeting the ligand to the lysosome. IGFs in biological fluids are mostly bound to IGFBP. IGFBPs, in general, are IGF storage/carrier proteins or modulators of IGF actions; however, as for distinct roles for individual IGFBPs, only limited information is available. IGFBPs inhibit IGF actions under most in vitro situations, seemingly because affinities of IGFBPs for IGFs are greater than those of IGF receptors. How IGF is released from IGFBP to reach IGF receptors is not known; however, various IGFBP protease activities that are present in blood and interstitial fluids are believed to play an important role in the process of IGF release from the IGFBP. According to latest reports, there is evidence that under certain in vitro circumstances, IGFBP-1, -3, -5 have their own biological activities independent of the IGF. This may add another dimension of complexity of the already complicated IGF system. Messenger ribonucleic acids and proteins of the IGF family members are expressed in the uterine tissue and conceptus of the primates, rodents and farm animals to play important roles in growth and development of the uterus and fetus. Expression of the uterine IGF system is regulated by gonadal hormones and local regulatory substances with temporal and spatial specificities. Locally expressed IGFs and IGFBPs act on the uterine tissue in an autocrine/paracrine manner, or are secreted into the uterine lumen to participate in conceptus growth and development. Conceptus also expresses the IGF system beginning from the peri-implantation period. When an IGF family member is expressed in the conceptus, however, is determined by the presence or absence of maternally inherited mRNAs, genetic programming of the conceptus itself and an interaction with the maternal tissue. The site of IGF action also follows temporal (physiological status) and spatial specificities. These facts that expression of the IGF system is temporally and spatially regulated support indirectly a hypothesis that IGFs play a role in conceptus growth and development. Uterine and conceptus-derived IGFs stimulate cell division and differentiation, glucose and amino acid transport, general protein synthesis and the biosynthesis of mammotropic hormones including placental lactogen and prolactin, and also play a role in steroidogenesis. The suggested role for IGFs in conceptus growth and development has been proven by the result of IGF-I, IGF-II or IGF receptor gene disruption(targeting) of murine embryos by the homologous recombination technique. Mice carrying a null mutation for IGF-I and/or IGF-II or type I IGF receptor undergo delayed prenatal and postnatal growth and development with 30-60% normal weights at birth. Moreover, mice lacking the type I IGF receptor or IGF-I plus IGF-II die soon after birth. Intrauterine IGFBPs generally are believed to sequester IGF ligands within the uterus or to play a role of negative regulators of IGF actions by inhibiting IGF binding to cognate receptors. However, when it is taken into account that IGFBP-1 is expressed and secreted in primate uteri in amounts assessedly far exceeding those of local IGFs and that IGFBP-1 is one of the major secretory proteins of the primate decidua, the possibility that this IGFBP may have its own biological activity independent of IGF cannot be excluded. Evidently, elucidating the exact role of each IGFBP is an essential step into understanding the whole IGF system. As such, further research in this area is awaited with a lot of anticipation and attention.

• Clinical and Experimental Reproductive Medicine
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• v.25 no.3
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• pp.281-286
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• 1998

Premature ovarian failure is a condition causing amenorrhea, hypoestrogenism, and elevated gonadotropins in women younger than 40 years. Many causes of premature ovarian failure were reported, including genetic abnormalities, enzymatic defects, defects in gonadotropin secretion or action, autoimmune disorders, physical and idiopathic causes. Recently, Finnish group reported a point mutation in the follicle stimulating hormone (FSH) receptor gene in premature ovarian failure patients. But it was reported that the group from United States could not find any mutation in FSH receptor gene. So we analysed C566T point mutation of FSH receptor gene using restriction fragment length polymorphism (RFLP) and compared the result between premature ovarian failure patient with idiopathic and known causes. But we did not find 556C${\rightarrow}$T mutation in the FSH receptor gene in both groups. These findings suggest that the missense mutation in the human FSH receptor gene reported in Finnish women with premature ovarian failure is uncommon in Korean women with premature ovarian failure.

• Development and Reproduction
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• v.14 no.4
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• pp.287-295
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• 2010

It was recently reported that nesfatin-1/NUCB2, which is secreted from the brain, controls appetite and energy metabolism. The purpose of this research was to confirm whether or not the protein and its binding site should have been expressed in the mouse reproductive organs and to know the possible effects of nesfatin-1 on the reproductive function. Using the ICR female mouse ovary and uterus, the expression of NUCB2 mRNA was confirmed with the conventional PCR and the relative amount of NUCB2 mRNA in the tissues was analyzed with real-time PCR. Immunohistochemical staining was performed using the nesfatin-1 antibody to investigate the nesfatin-1 protein expression and the biotin conjugated nesfatin-1 to confirm the binding site for nesfatin-1 in the ovary. Furthermore, in order to examine if the expression of NUCB2 mRNA in the ovary and uterus is affected by gonadotropin, its mRNA expression was analyzed after PMSG administration into mice. As a result, the expression level of NUCB2 mRNA in the ovary and the uterus was as much as the expression level in hypothalamus. As a result of the immunohistochemical staining, nesfatin-1 proteins were localized at the theca cells, the interstitial cells, and some of the luteal cells. However, the granulosa cells in the follicles did not stain. Interestingly, the oocytes in the some follicles were stained with nesfatin-1. On the other hand, nesfatin-1 protein binding sites were displayed at the theca cells and the interstitial cells near the tunica albuginea. After PMSG administration the expression level of NUCB2 mRNA was increased in the ovary and the uterus. These results demonstrate that for the first time the nesfatin-1 and its binding site were expressed in the ovary and NUCB2 mRNA expression was controlled by gonadotropin, suggesting an important role in the reproductive organs as a local regulator. Therefore, further study is needed to elucidate the functions of nesfatin-1 on the reproductive organs.

• Clinical and Experimental Reproductive Medicine
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• v.31 no.2
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• pp.133-139
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• 2004

Objective: To investigate the association of FSH receptor (FSHR) polymorphism at position 680 with outcomes of controlled ovarian hyper-stimulation for IVF-ET in Korean women. Design: Genetic polymorphism analysis. Materials and Methods: The FSHR polymorphism was analyzed by PCR-RFLP in 172 ovulatory women below the age of 40 year. Patients with polycystic ovary syndrome, endometriosis, or previous history of ovarian surgery were excluded. Results: Genotype distribution was 41.9% for the Asn/Asn, 47.7% for the Asn/Ser, and 10.5% for the Ser/Ser FSHR genotype group. There was no difference in age of subjects and infertility diagnosis between genotype groups. When the patients were grouped according to their FSHR genotype, the basal levels of FSH (day 3) were significantly different among the three groups ($6.0{\pm}0.3\;IU/L$ (mean $\pm$ SEM), $5.8{\pm}0.3\;IU/L$, and $8.6{\pm}1.2\;IU/L$ for the Asn/Asn, Asn/Ser, and Ser/Ser groups, respectively, p=0.002). The Ser/Ser group showed a higher total doses of gonadotropins required to achieve ovulation induction, and a lower serum estradiol levels at the time of hCG administration compared with other two groups, but the differences were of no statistical significance. The numbers of oocytes retrieved were significantly different among the three groups ($8.6{\pm}0.8$, $9.9{\pm}0.6$, and $6.3{\pm}0.9$, for the Asn/Asn, Asn/Ser, and Ser/Ser groups, respectively, p=0.049). Clinical pregnancy rates were 42.4%, 25.9%, and 29.4% for the Asn/Asn, Asn/Ser, and Ser/Ser groups, respectively. Conclusion: Homozygous Ser/Ser genotype of FSHR polymorphism at position 680 was associated with decreased ovarian response to gonadotropin stimulation for IVF-ET.