• Development and Reproduction
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• v.5 no.1
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• pp.59-71
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• 2001

Since the first radioimmunoassay (RIA) was developed in 1970s, many conventional RIAs and non-isotopic immunoassays (NIA) had been developed in which the degree of precision, accuracy, specificity and practicability have progressively increased. Recently ultrasensitive assay method at femtogram to determine testosterone in serum, saliva and feces is required for the study of sexual dysfunctions in male and female, monitoring the psychological stress and conditions, aging process such as menopause and partial androgen deficiency in aging male, the hormonal changes of small experimental animals etc. This review discussed the recentd evelopments of steroid assay methods, based upon the testosterone assay results of authors far 20 years, and the problems associated the assay set-up, the characterizations and applications of the established procedures, and desifls of assay, reliablity criteria, and the practical aspects of assay set-up and application, based upon the data of the authors. The present study demonstrates the general problems methods to be consider in order to set up the highly sensitive assay methods and to increase the assay quality and the necessity of assay quality control program. To improve the assay quality of each laboratory and to compare the assay results in homeland, the national QC programs should be organized.

• Tuberculosis and Respiratory Diseases
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• v.80 no.4
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• pp.385-391
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• 2017

Background: Men with chronic obstructive pulmonary disease, have reduced endogenous testosterone levels, but the relationship between pulmonary function and endogenous testosterone levels, is inconsistent. Testicular volume is a known indicator of endogenous testosterone levels, male fertility, and male potency. In the present study, the authors investigated the relationship, between testicular volume and lung function. Methods: One hundred and eighty-one South Korean men age 40-70, hospitalized for urological surgery, were retrospectively enrolled, irrespective of the presence of respiratory disease. Study subjects underwent pulmonary function testing, prior to procedures, and testicular volumes were measured by orchidometry. Testosterone levels of patients in blood samples collected between $7{\small{AM}}$ and $11{\small{AM}}$, were measured by a direct chemiluminescent immunoassay. Results: The 181 study subjects were divided into two groups, by testicular volume (${\geq}35mL$ vs. <35 mL), the larger testes group, had better lung functions (forced vital capacity [FVC]: $3.87{\pm}0.65L$ vs. $3.66{\pm}0.65L$, p=0.037; forced expiratory volume in 1 second [$FEV_1$]: $2.92{\pm}0.57L$ vs. $2.65{\pm}0.61L$, p=0.002; FVC % predicted: $98.2{\pm}15.2%$ vs. $93.8{\pm}13.1%$, p=0.040; $FEV_1$ % predicted: $105.4{\pm}19.5%$ vs. $95.9{\pm}21.2%$, p=0.002). In addition, the proportion of patients with a $FEV_1/FVC$ of <70%, was lower in the larger testes group. Univariate analysis conducted using linear regression models, revealed that testicular volume was correlated with FVC (r=0.162, p=0.029), $FEV_1$ (r=0.218, p=0.003), $FEV_1/FVC$ (r=0.149, p=0.046), and $FEV_1$ % predicted (r=0.178, p=0.017), and multivariate analysis using linear regression models, revealed that testicular volume was a significant predictive factor for $FEV_1$ % predicted (${\beta}=0.159$, p=0.041). Conclusion: Larger testicular volume was independently associated, with favorable indices of lung function. These results suggest that androgens, may contribute to better lung function.

• Development and Reproduction
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• v.10 no.3
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• pp.197-202
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• 2006

Sex steroids are generally considered as natural sex inducers in fish, and aromatase (cytochrome P450 aromatase) that catalyzes androgens into estrogens in the steroidogenic pathway is also known to be involved in sex differentiation. The timing of aromatase action is, thus, of central importance in the study of fish sex differentiation. We treated sexually undifferentiated tilapia (Oreochromis niloticus) larvae with $Fadrozole^{TM}$, a non-steroidal aromatase inhibitor (AI), by immersing the fish in a solution containing AI during the sex differentiation period to narrow down the critical period of aromatase action. Fish were treated once at 11 or 13 days post fertilization (dpf), or twice at 11 and 13 dpf. The concentrations of AI at each time of the treatment were 0 mg/L (control), 50 mg/L or 100 mg/L. Survival rate was not statistically associated with AI immersion treatment (p>0.25). However, sex ratio was significantly altered by the treatment, with higher concentration and double immersion being more effective in masculinizing genetic females (p<0.05). These results suggest that aromatase action for sex differentiation in this fish species would begin at least from 11 dpf which is much earlier than previously expected, and that only 3 hours of brief immersion in AI solution is powerful enough to alter genetically programed sex.

• Journal of Life Science
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• v.29 no.4
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• pp.395-401
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• 2019

Phthalate is a chemical endocrine disrupter and interfere with the action of hormones, estrogens, androgens and thyroid hormones. It also affect cardiovascular, metabolic, immune and reproductive system in the human and animals. Curcumin is antioxidant, anti-inflammatory activity and -cancer properties in the human. We studied whether phthalates damage viability, mitochondrial activity and membrane integrity of sperm in boar semen. We also treated curcumin with/without phthalates in the boar semen. Fresh boar semen was treated with phthalates and/or curcumin for examining sperm characteristics. Sperm characteristics, sperm motility, viability, mitochondrial activity, and membrane integrity were determined during storage of boar semen. Sperm motility and viability in dose-dependent manner decreased by di-n-butyl phthalate (DBP), mono-n-butyl phthalate (MBP) and di-2-ethylhexyl phthalate (DEHP, p<0.05). Phthalates also decreased mitochondrial activity and membrane integrity of sperm (p<0.05). However, sperm motility and viability were higher than untreated-curcumin when DBP, MBP and DEHP treated with a curcumin in boar semen (p<0.05). Mitochondrial activity and membrane integrity of sperm were higher in DBP- and MBP-treated semen with curcumin (p<0.05). In conclusion, phthalates can damage sperm viability and quality during the boar semen storage, and curcumin may protect the boar sperms from phthalates during storage term.

• Korean Journal of Poultry Science
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• v.33 no.3
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• pp.181-188
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• 2006

Changes in the fine structure of testicular Leydig cell from hatching to adulthood were studied in Korean native chickens of 1, 2, 4, 6, 8, 10, 12, 14, 16, 18, 21, 24, 28, 32, 44, 52 and 64 weeks (n=13 chickens per group) of age. The objective of this study were to elucidate Leydig cell ultrastructure during testicular development. Testes of chickens were fixed by whole body perfusion using a fixative containing 2.5% glutaraldehyde in cacodylate buffer, processed and embedded in Epon-araldite. Using $1{\mu}m$ sections stained with methylene blue-azure II, qualitative and quantitative(stereological) morphological studies were performed. The ultrastructural changes of the Leydig cell were investigated by ultrathin section with the transmission electron microscope. The stages of the Leydig cell development described focus on mitochondria, endoplasmic reticulum, and lipid droplets which are involved in androgens as fullows. 1) Approaching puberty. The closely packed Leydig cells and sparse intercellular space. The nucleus occupied a large portion of the Leydig cell volume. The population of Leydig cells contained two types of cells that differed in the appearance of their nuclei which were either highly electron-opaque or relatively electron-lucid. The cytoplasm was characterized by large amounts of lipid droplets, relatively few spherical mitochondria, and sparse smooth endoplasmic reticulum. 2) Puberty to adult. The Leydig cells which display features compatible with significant androgen synthesis: large volume of cytoplasm containing extended smooth endoplasmic reticulum, abundant mitochondria, and reduction of lipid droplets.

• Development and Reproduction
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• v.12 no.1
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• pp.97-105
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• 2008

Vinclozolin (VCZ) is a systemic fungicide commonly used in fruits, vegetables and the wine industry. VCZ and its metabolites, butenoic acid (M1) and enanilide (M2) derivatives, act as anti-androgens through actions on the androgen receptor. Although there is growing body of evidence that VCZ's action as an endocrine disrupting chemical (EDC) in male reproductive physiology and pathphysiology, no evidence on the VCZ's EDC action in female is available yet. Previously we found that the prepubertal VCZ exposures could effectively delay the onset of puberty in female rats, suggesting the postponed or weakened activities of hypothalamus-pituitary-ovary (H-P-O) reproductive hormonal axis. The present study was performed to examine whether the VCZ administration affects the transcriptional activities of reproductive hormone-related genes in the same animal model. VCZ (10 mg/kg/day) was administered daily from postnatal day 21 (PND 21) through the day when the first vaginal opening (V.O.) was observed. To determine the transcriptional changes of reproductive hormone-related genes in hypothalamus and pituitary, total RNAs were extracted and applied to the semiquantitative reverse transcription polymerase chain reaction (RT-PCR). As a result, treatment with VCZ significantly lowered the transcriptional activity of nitric oxide synthase-2 (NOS-2) which is known to adjust gonadotropin-releasing hormone (GnRH) secretion in the hypothalamus (p<0.01). Similarly, the mRNA levels of KiSS-1, G protein-coupled receptor 54 (GPR54) and GnRH were significantly decreased in hypothalamus (p<0.01) from VCZ-treated group. As expected, the transcriptional activities of luteinizing hormone-${\beta}$ (LH-${\beta}$) and follicle stimulating hormone-${\beta}$ (FSH-${\beta}$) in the anterior pituitary from VCZ-treated group were also significantly lower than those from the control group. The present study indicates that(i) the inhibitory effect of VCZ exposure on the onset of puberty in immature female rats could be derived from the reduced transcriptional activities of gonadotropin subunits and their upstream modulators such as GnRH and KiSS-1 in hypothalamus-pituitary neuroendocrine axis, and (ii) these inhibitory effects could be mediated by NO signaling pathway.

• Clinical and Experimental Reproductive Medicine
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• v.40 no.3
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• pp.135-140
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• 2013

Objective: To evaluate correlations between serum anti-M${\ddot{u}}$llerian hormone (AMH) levels, phenotypes of polycystic ovary syndrome (PCOS), obesity, and metabolic parameters in patients with PCOS. Methods: A total of 175 patients with PCOS were diagnosed according to the Rotterdam Consensus were included. Exclusion criteria were age over 40, FSH>25 mIU/mL, and 17a-OHP>1.5 ng/mL. The Phenotypes of PCOS were divided into a severe form (oligo-anovulation, ANOV/hyperandrogenism/polycystic ovary morphology [PCOM]; n=59) and a mild form without HA (ANOV/PCOM, n=105). The serum AMH levels were classified into 3 groups (<5 vs. 5-10 vs. >10 ng/mL). Obesity was defined as body mass index (BMI) ${\geq}25kg/m^2$ (n=34). Results: The mean age was $25.9{\pm}5.7$ year and mean AMH level was $10.1{\pm}5.4$ ng/mL. The BMI ($kg/m^2$) was higher in group 1 ($24.2{\pm}6.3$) than in group 2 ($21.9{\pm}4.3$, p=0.046) or group 3 ($21.6{\pm}3.3$, p=0.019). There was no difference among the three groups in age, menstrual interval, antral follicle counts, androgens, or other metabolic parameters. The obesity group showed significantly lower AMH ($7.7{\pm}3.9$ ng/mL vs. $10.7{\pm}5.6$ ng/mL), p=0.004) and low-density lipoprotein levels ($93.1{\pm}21.2$ mg/dL vs. $107.5{\pm}39.3$ mg/dL, p=0.031), and showed higher total T ($0.74{\pm}0.59$ L vs. $0.47{\pm}0.36$ ng/mL, p=0.001), free T ($2.01{\pm}1.9$ vs. $1.04{\pm}0.8$ pg/mL, p=0.0001), and free androgen index ($6.2{\pm}7.9$ vs. $3.5{\pm}3.0$, p=0.003). After controlling for age factors and BMI, the serum AMH levles did not show any significant correlations with other hormonal or metabolic parmeters. Conclusion: For PCOS patients under the age 40, serum AMH is not negatively correlated with age. High serum AMH levels can not predict the phenotype of PCOS and metabolic disturbances in PCOS patients in the non-obese group. Further study might be needed to define the relation more clearly.

• Korean Journal of Veterinary Research
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• v.32 no.1
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• pp.15-24
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• 1992

The effects of CC the ovulatory response, oocyte normality, ovarian steroidogenesis and subsequent embryo developmental potential were examined in PMSG-treated rats. On Days of 25~27 of age, immature female Sprague Dawley rats were treated with three different doses(0.05, 0.1 or 1.0mg /day) of clomiphene citrate or vehicle. The females subsequently received 4IU PMSG on Day 28 and/or 10IU hCG on Day 30, and were killed on Day 31. Some females given 0.1mg CC or vehicle with 4IU PMSG were then mated and killed on Days 2, 3, 4 and 5 of pregnancy. Compared to vehicle(control) group, by increasing the doses of CC, there were a significant decrease in the ovulatory response as judged by both the proportion of rats ovulating and the mean number of oocytes per rat and a marked reduction of ovarian weight. The increasing doses of CC substantially promoted the degeneration(%) of oocytes ovulating in a dose-dependent manner. The CC-mediated inhibitions of the ovulatory response and ovarian weight were oompletely overcome by a subsequent treatment of hCG. Increasing doses of CC resulted in a siginificant elevation of serum estradiol with the decreased levels of progesterone and androgens. The additive treatment with hCG was effective to reduce the elevation of estradiol and to increase the reduction of progesterone produced by high dose(1.0mg) of CC. The preimplantation embryos recovered from 0.1mg CC-treated pregnant rats demonstrated a progressive early loss from Day 3 of pregnancy with a significant increase in the percentage of degeneration during all periods examined, compared to controls. The rate of progressive embryo cleavage in the CC-treated rats were slower than that in controls from Day 3 of pregnancy. Additionally, the percentage of the cleaved embryos recovered from the CC-treated rats remained significantly lower consistently from Day 2 of pregnancy, compared to control regimen. These results demonstrate a possible mechanism of CC-mediated inhibition of ovulatory response in the rats which may include the attenuation or blockade of the endogenous secretion of gonadotropins and also suggest that its detrimental effects observed on oocyte normality and embryonic development may be caused by abnormal follicular steroidogenesis( especially elevated estradiol) preceding fertilization.