• Korean Journal of Animal Reproduction
• /
• v.24 no.4
• /
• pp.357-364
• /
• 2000

Members of the glycoprotein family, which includes CG, LH, FSH and TSH, comprise two noncovalently linked $\alpha$- and $\beta$-subunits. Equine chorionic gonadotropin (eCG), known as PMSG, has a number of interesting and unique characteristics since it appears to be a single molecule that possesses both LH- and FSH-like activities in other species than the horse. This dual activity of eCG in heterologous species is of fundamental interest to the study of the structure-function relationships of gonadotropins and their receptors. CG and LH $\beta$ genes are different in primates. In horse, however, a single gene encodes both eCG and eLH $\beta$ -subunits. The subunit mRNA levels seem to be independently regulated and their imbalance may account for differences in the quantities of $\alpha$ - and $\beta$-subunits in the placenta and pituitary. The dual activities of eCG could be separated by removal of the N-linked oligosaccharide on the $\alpha$-subunit Asn 56 or CTP-associated O-linked oligosaccharides. The tethered-eCG was efficiently secreted and showed similar LH-like activity to the dimeric eCG. Interestingly, the FSH-like activity of the tethered-eCG was increased markedly in comparison with the native and wild type eCG. These results also suggest that this molecular can implay particular models of FSH-like activity not LH-like activity in the eCG/indicate that the constructs of tethered molecule will be useful in the study of mutants that affect subunit association and/or secretion. A single-chain analog can also be constructed to include additional hormone-specific bioactive generating potentially efficacious compounds that have only FSH-like activity. The LH/CG receptor (LH/CGR), a membrane glycoprotein that is present on testicular Leydig cells and ovarian theca, granulosa, luteal, and interstitial cells, plays a pivotal role in the regulation of gonadal development and function in males as well as in nonpregnant and pregnant females. The LH/CGR is a member of the family of G protein-coupled receptors and its structure is predicted to of a large extracellular domain connected to a bundle of seven membrane-spanning a-helices. The LH/CGR phosphorylation can be induced with a phorbol ester, but not with a calcium ionophore. The truncated form of LHR also was down-regulated normally in response to hCG stimulation. In contrast, the cell lines expressing LHR-t631 or LHR-628, the two phosphorylation-negative receptor mutant, showed a delay in the early phase of hCG-induced desensitization, a complete loss of PMA-induced desensitization, and an increase in the rate of hCG-induced receptor down-regulation. These results clearly show that residues 632~653 in the C-terminal tail of the LHR are involved in PMA-induced desensitization, hCG-induced desensitization, and hCG-induced down-regulation. Recently, constitutively activating mutations of the receptor have been identified that are associated with familial male-precocious puberty. Cells expressing LHR-D556Y bind hCG with normal affinity, exhibit a 25-fold increase in basal cAMP and respond to hCG with a normal increase in cAMP accumulation. This mutation enhances the internalization of the free and agoinst-occupied receptors ~2- and ~17- fold, respectively. We conclude that the state of activation of the LHR can modulate its basal and/or agonist-stimulated internalization. Since the internalization of hCG is involved in the termination of hCG actions, we suggest that the lack of responsiveness detected in cells expressing LHR-L435R is due to the fast rate of internalization of the bound hCG. This statement is supported by the finding that hCG responsiveness is restored when the cells are lysed and signal transduction is measured in a subcellular fraction (membranes) that cannot internalize the bound hormone.

• Korean Journal of Ichthyology
• /
• v.3 no.1
• /
• pp.48-57
• /
• 1991

Changes of the activities of the hepatic cells of female mud skipper, Boleophthalmus pectinirostris were investigated under transmission electron microscopy. Monthly changes of gonadosomatic index(GSI) and hepatosomatic index(HSI), variations of protein and nucleic acid contents(total RNA and DNA) of the liver tissues with the gonadal development phase were also studied. GSI began to increase from May(the growing stage), reaching the maximum value in late June(the mature stage), and then it began to decrease from late July(the degenerative stage), reaching the lowest value in late September. Monthly variations of HSI were negatively related to GSI. HSI decreased in the summer season when the ovary was getting mature and reached the maximum in mid October when the ovary was degenerating. In June(the mature stage), the female hepatic cells of the liver tissues became large and nuclei were hypertrophic. The amounts of glycogen particles and lipid droplets in the cells gradually decreased, while a number of granular endoplasmic reticulum increased. It was assumed that well-developed granular endoplasmic reticulum binding ribosomes are supposed to play the leading role in protein synthesis and deposition for vitellogenin in the cytoplasm. In July(the spawning period), glycogen particles and lipid droplets gradually increased, and then these substances were still observed in large quantity in August(the degenerative stage). The protein contents of the liver tissues with the gonadal phases of the ovaries were shown the maximum value($4.720{\pm}0.103\;mg/g$) in June, and afterwards gradually decreased being the minimum($3.640{\pm}0.130\;mg/g$) in July, and then gradually increased in August. The mean total RNA contents per gram of the liver tissues appeared the maximum($0.523{\pm}0.040\;mg/g$) in June, and afterwards gradually decreased to the minimum($0.158{\pm}0.006\;mg/g$) in July and slightly increased in August again. From these results, it could be assumed that protein contents were closely related to RNA contents. The mean total DNA contents per weight (gr) of the liver tissues appeared to be similar although there were some monthly fluctuations. The ratio of the mean total RNA/DNA were 0.745 in June, 0.262 in July, 0.341 in August respectively.

• The Korean Journal of Zoology
• /
• v.39 no.3
• /
• pp.273-281
• /
• 1996

Previously, we have proposed a two-cell type model for follicular steroidogenesis inamphibians with Rana nigromacu lota. Present experiments were carried out to ascertain whether the model Is applicable to R. dybowskii. The role of theca layer were also reassessed by using granulosa cell-free pure theca layer (P-THEP). Theca/epithelium (THEP) layers, P-THEP layers, and granulosa cell enclosed-oocytes () were obtained from ovarian follicles of R. dybowskii by microdissection. Intact follicles (IFs) and different types of tissues were cultured for 6 hour in amphibian Ringer's m the presence or absence of FPII (0.05 gland/mi) or various steroid precursor (100 ng/ml). The amounts of product steroids converted by the components were measured by RIA. Exogenously added pregnenolone (P5) resulted in a marked increase in progesterone (P$_4$) by GCEOs (2143 pg/follicle) and IFs (2346 pg/follicle) but a smaller increase in P4 by THEP layer (495 pg/follicle). Addition of P$_4$ increased 17 a-hydroxyprogesterone (17 $\alpha$-OHP$_4$) levels by GCEOs (1118 pg/follicle) and IFs (1333 pg/follicle) but less by THEP layer (290 pg/follicle). However, much less amounts of P$_4$ or 17 $\alpha$-OHP$_4$ were producad by P-THEP layers than THEP in the presence of P5. Exogenous 1 7$\alpha$-OIIP$_4$ increased androstenedione (AD) levels by GCEOs (1415 pg/follicle) and IFs (561 pg/follicle) but not by THEP layers. In contrast, addition of AD resulted m a marked increase in testosterone (T) levels by TIIEP (2594 pg/follicle) and IFs (2223 pg/follide) but much less by GCEOs (339 pg/follicle). Exogenous T increased estradiol (E$_2$) levels by GCEOs (551pg/follicle) and IFs (887 pg/follicle), but not by THEP layer (<10 pg/follicle). Without addition of FPH or steroid precursors, very low or nondetectable levels of steroids were produced (< 20 pg/follicle) by all the types of follicular components examined. The data presented here indicate that the two-cell type model based on the study with R. nigromacu Iota is applicable to R. dybowskii and also suggest that the minor pathway, which convert P5 to 17$\alpha$-OHP$_4$, is not present in theca layer.

• Applied Microscopy
• /
• v.39 no.1
• /
• pp.1-7
• /
• 2009

Experimental induction of polycystic ovary (PCO) resembling some aspects of human PCO syndrome was produced using the long-acting compound estradiol valerate (EV). Our previous study on the role of Korean red ginseng total saponins (GTS) in a steroid-induced PCO rat model demonstrated that electro-acupuncture modulates nerve growth factor (NGF) concentration in the ovaries. In fact, the involvement of a neurogenic component in the pathology of PCO-related ovarian dysfunction is preceded by an increase in sympathetic outflow to the ovaries. In the present study, we tested the hypothesis that therapeutic GTS administration modulates sympathetic nerve activity in rats with PCO. This was done by analyzing NGF protein and NGF mRNA expression involved in the pathophysiological process underlying steroid-induced PCO. EV injection resulted in significantly higher ovarian NGF mRNA expression in PCO rats compared to control rats, and PCO ovaries were counteracted by GTS administration with significantly lower expression of NGF mRNA compared to EV treated ovaries. However, NGF protein was unaffected in both EV and GTS treated ovaries compared to control rats. These results indicate that EV modulates the neurotrophic state of the ovaries, which may be a component of the pathological process by which EV induces cyst formation and anovulation in rodents.

• Asian-Australasian Journal of Animal Sciences
• /
• v.16 no.4
• /
• pp.481-488
• /
• 2003

Insulin-like Growth Factors (IGFs) and IGF-binding protein act as intra-ovarian regulators that modulate the proliferation and differentiation of the granulosa and theca cells. Moreover, the IGF system is involved in metabolism by modulating the synthesis and degradation of glycogen and protein in animals. However the effect of the IGF system on egg productivity or body growth in KNOC has not been studied in depth. Therefore, this study was performed to investigate differences of serum IGFs and binding protein expressions between two groups showing high and low egg production or body weight and to elucidate the relationship of IGFs with egg productivity and body growth. KNOCs were divided into high and low groups depending on their egg productivity or body growth, and sera were collected every 10 wk from 20 till 60 wk. Serum IGF-I and -II concentration were measured by RIA using human and mouse antiserum and chicken standards. IGFBP was detected by Western ligand blotting. IGF-I concentrations were significantly greater in the high egg production group compared with those in the low egg production group (30 wk, p<0.01; 20 and 40 wk, p<0.05). Also, differences in IGF-II amounts between the two groups were detected at 60 wk (p<0.05). But IGFBPs in the low egg production group were more intense than that in the high egg production group through the egg laying period. The correlation between IGF-I concentration and number of egg production is significantly positive (20 wk, r=0.2729: p<0.05; 40 wk, r=0.3500: p<0.01), while IGF-II shows no correlation with egg productivity. In male KNOC, IGF-I and -II concentrations in the high body weight group are lower than that in the low body weight group. Body weight also shows a negative correlation with the serum IGF-II concentration in male chickens (20 wk, r=-0.5901: p<0.01). Consequently, we suggest that IGFs and binding protein are (in)directly involved in the egg productivity and body growth in KNOC.

• Asian Pacific Journal of Cancer Prevention
• /
• v.16 no.16
• /
• pp.7129-7138
• /
• 2015

Background: The polycystic ovary syndrome (PCOS), characterized by hyperandrogenism and chronic anovulation, is a common endocrine disorder in women. PCOS, which is associated with polycystic ovaries, hirsutism, obesity and insulin resistance, is a leading cause of female infertility. In this condition there is an imbalance in female sex hormones. All the sequelae symptoms of PCOS gradually lead to cancer in the course of time. It is heterogeneous disorder of unknown etiology so it is essential to find the exact cause. Materials and Methods: In this study both invasive and non-invasive techniques were employed to establish the etiology. Diagnosis was based on Rotterdam criteria (hyperandrogenism, ovulatory dysfunction, PCOM) and multiparameters using buccal samples and dermatoglypic analysis and cytogenetic study for 10 cases and four age and sex matched controls. Results: In clinical analysis we have observed the mean value of total testosterone level was 23.6nmol/L, total hirsutism score was from 12-24, facial acne was found in in 70% patients with 7-12 subcapsular follicular cysts, each measuring 2-8 mm in diameter. In dermatoglypic analysis we observed increases in mean value ($45.9^{\circ}$) of ATD angle when compared with control group and also found increased frequency (38%) of Ulnar loops on both fingers (UU), (18%) whorls on the right finger and Ulnar loop on left finger (WU) and (16%) arches on right and left fingers (AA) were observed in PCOS patients when compared with control subjects. Features which could be applied as markers for PCOS patients are the presence of Ulnar loops in middle and little fingers of right and left hand. The buccal micronucleus cytome assay in exfoliated buccal cells, we found decrease in frequency of micronuclei and significant increases in frequency of karyolysed nuclei in polycystic ovarian syndrome patients. Chromosome aberration analysis revealed a significant increase in frequency of chromosome aberrations (CAs) in PCOS patients when compared with controls. Conclusions: From this present work it can be concluded that non-invasive technique like dermatoglypics analysis and buccal micronucleus cytome assays with exfoliated buccal cell can also be effective biomarkers for PCOS, along with increased CAs in lymphocytes as a sign of genetic instability. There is a hypothesis that micronuclei and chromosomal aberrations could have a predictive value for cancer. From this present work it can be concluded to some extent that non-invasive technique like dermatoglypics and buccal cell analysis can also be effective for diagnosis.

• The Korean Journal of Malacology
• /
• v.25 no.2
• /
• pp.145-151
• /
• 2009

The ultrastructural changes in germ cells during oogenesis of the melania snail, Semisulcospira libertina libertina have been investigated by light and electron microscopy. The ovary is located on the surface of the hepatopancreas in the spiral posterior region. The ovary exhibited greenish color in the gonadal mature season. The ovary was composed of a number of oogenic follicles. Oogenesis was divided into five stages with histological features: (1) oogonia, (2) previtellogenic, (3) initial vitellogenic, (4) active vitellogenic, and (5) mature stages. Oogonia were oval in shape, $4-6\;{\mu}m$ in diameter, and had a large nucleus. Previtellogenic oocytes were about $20\;{\mu}m$ in diameter and the cytoplasm reacted with hematoxylin in H-E satin. Initial vitellogenic stage, oocytes were $60-80\;{\mu}m$ in diameter, and small yolk granules of low electron density are scattered in the cytoplasm. Oocytes in the initial vitellogenic stage were connected with ovarian follicle by egg stalk. Active vitellogenic oocyte were $100-120\;{\mu}m$ in diameter. Electron density, size and quantity of yolk granules that are distributed in the cytoplasm have increased from the previous stage. Result of TEM observations, the oocyte contains well-developed Golgi complex, endoplasmic reticula and tubular mitochondria in the cytoplasm. Cytoplasm of mature oocyte was filled with proteinaceous yolk globules of high electron density. In this stage, the length of microvilli in the egg envelope was approximately $1.1\;{\mu}m$.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.33 no.5
• /
• pp.373-377
• /
• 2000

This study Investigated the effects of $estradiol-l7{\beta} (E_2)$, $17{\alpha}-methyltestosterone$ (MT) and high temperature (WT) on gonadal sex differentiation in black rockfish, Sebastes srhlegeli. fish were reared to oral adminstration of E, at nominal concentrations of $20, 40 and 60 {\mu}g/g diet$, and MT at nominal concentration of 20 and $50 {\mu}g/g$ diet from 56 days to 77 days after parturition. In the treatment of WT, water temperature of the breeding tanks ranged $27.0{\pm}0.5^{\circ}C$ more than $10^{\circ}C$ approximately, in comparison to the control and other experimental group, In the process of sex differentiation until 56 days after parturition, gonads were composed of mostly gonia cells, sexually undifferentiated. In contrast, 128 dal's after parturition, the ovaries were composed of ovarian cavity and lamellae, and oogonia and perinucleolus oocytes were distributed in the lamellae of ovary, and the testes were composed of a number of seminiferous tubule, and spermatogonia were distributed in the seminiferous tubule, and also melanophore scattered in the matrix layer of testis. In the sex ratio, more females than male were observed from $E_2$. treatment groups when compared to the control, but more males than females were observed from MT and WT treatment groups when compared to the control. In the results of the present study, the concentration and kinds of the sex steroid hormones, and also the rearing high temperature caused to the factor of sex determination in the process of sex differentiation of black rockfish.

• Archives of Pharmacal Research
• /
• v.21 no.5
• /
• pp.581-590
• /
• 1998

We developed a novel water-soluble camptothecin analobue, CKD602, and evaluated the inhibition of topoisomerase I and the antitumor activities against mammalian tumor cells and human tumor xenografts. CKD602 was a nanomolar inhibitor of the topoisomerase I enzyme in the cleavable complex assay. CKD602 was found to be 3 times and slightly more potent than topotecan and camptothecin as inhibitors of topoisomerase, respecitively. In tumor cell cytotoxicity, CKD602 was more potent than topotecan in 14 out of 26 human cancer cell lines tested, while it was comparable to camptothecin. CKD602 was tested for the in vivo antitumor activity against the human tumor xenograft models. CKD602 was able to imduce regression of established HT-29, WIDR and CX-1 colon tumors, LX-1 lung tumor, MX-1 breast tumor and SKOV-3 ovarian tumor as much as 80, 94, 76, 67, 87% and 88%, respectively, with comparable body weight changes to those of topotecan. Also the therapeutic margin (R/Emax: maximum tolerance dose/$ED-{58}$) of CKD602 was significantly higher than that of topotecan by 4 times. Efficacy was determined at the maximal tolerated dose levels using schedule dependent i.p. administration in mice bearing L1210 leukemia. On a Q4dx4 (every 4 day for 4 doses) schedule, the maximum tolerated dose (MTD) was 25 mg/kg per administration, which caused great weight loss and lethality in <5% tumor bearing mouse. this schedule brought significant increase in life span (ILS), 212%, with 33% of long-term survivals. The ex vivo antitumor activity of CKD602 was compared with that of topotecan and the mean antitumor index (ATI) values recorded for CKD602 were significantly higher than that noted for topotecan. From these results, CKD602 warrants further clinical investigations as a potent inhibitor of topoisomerase I.

• Archives of Pharmacal Research
• /
• v.29 no.8
• /
• pp.666-676
• /
• 2006

Gangliosides are widely distributed in mammalian cells and play important roles in various functions such as cell differentiation and growth control. In addition, diabetes and obesity cause abnormal development of reproductive processes in a variety of species. However, the mechanisms underlying these effects, and how they are related, are not fully understood. This study examined whether the differential expression of gangliosides is implicated in the abnormal follicular development and uterine architecture of streptozotocin (STZ)-induced and db/db diabetic mice. Based upon the mobility on high-performance thin-layer chromatography, mouse ovary consisted of at least five different ganglioside components, mainly gangliosides GM3, GM1, GD1a and GT1b, and diabetic ovary exhibited a significant reduction in ganglioside expression with apparent changes in the major gangliosides. A prominent immunofluorescence microscopy showed a dramatic loss of ganglioside GD1a expression in the primary, secondary and Graafian follicles of STZ-induced and db/db diabetic mice. A significant decrease in ganglioside GD3 expression was also observed in the ovary of db/db mice. In the uterus of STZ-induced diabetic mice, expression of gangliosides GD1a and GT1b was obviously reduced, but gangliosides GM1, GM2 and GD3 expression was increased. In contrast, the uterus of db/db mice showed a significant increase in gangliosides GM1, GD1a and GD3 expression. Taken together, a complex pattern of ganglioside expression was seen in the ovary and uterus of normoglycemic ICR and $db/^+$ mice, and the correspoding tissues in diabetic mice are characterized by appreciable changes of the major ganglioside expression. These results suggest that alterations in ganglioside expression caused by diabetes mellitus may be implicated in abnormal ovarian development and uterine structure.