• Proceedings of the Zoological Society Korea Conference
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• 1996.10a
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• pp.252.2-252
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• 1996

No Abstract, See Full Text

• Proceedings of the Zoological Society Korea Conference
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• 2001.04a
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• pp.89.2-89
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• 2001

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.12
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• pp.1832-1842
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• 2007

Cytochrome P450 aromatase is responsible for the biosynthesis of estrogen. It is also responsible for the endogenous production of 19-nortestosterone (nandrolone), an anabolic androgen unique to pigs. Plasma concentrations of 19-nortestosterone are highest between two and four weeks after birth in male pigs. In the present study, the physiology of 19-nortestosterone was investigated by measuring the mRNA levels of steroidogenic enzymes, estrogen receptors and androgen receptor in the tissues of growing pigs. The expression of aromatase, 17${\alpha}$-hydroxylase and 3${\beta}$-hydroxysteroid dehydrogenase in the testes of male piglets increased between birth and two weeks of age, and then decreased progressively. Similar developmental expressional patterns were observed for 17${\alpha}$-hydroxylase and 3${\beta}$-hydroxysteroid dehydrogenase in the ovaries of female piglets, but without significant aromatase expression. The major form of aromatase expressed in the testes of piglets was identified as type I. Expression of estrogen receptor-${\alpha}$ and -${\beta}$and androgen receptor genes was also detected in both testes and ovaries. A transient elevation of androgen receptor mRNA in male piglets at two weeks of age was also observed in testes. Significant expression of the androgen receptor gene, but not of estrogen receptor-${\alpha}$ and -${\beta}$ genes, was also demonstrated in adipose tissue and muscle. We conclude that the observed increase in the testicular expression of aromatase in male pigs could account for the production of large amounts of 19-nortestosterone at between two and four weeks of age in males. Androgen receptor and 19-nortestosterone appeared to be important for testicular development and might contribute to sexual dimorphism in body composition and muscle development in juvenile pigs.

• Journal of Radiation Protection and Research
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• v.19 no.3
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• pp.179-188
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• 1994

Mice were whole body irradiated with dose of 2.88Gy and 7.2Gy(Co-60) in order to observe the morphological and functional changes in radio sensitive mouse ovary. Microtechnical sectionates of $7{\mu}m$ thickness from ovary were made for light microscopy and concentrations of progesterone, testosterone and estradiol in ovarian homogenates were analyzed by radioimmunoassay. Gamma radiation resulted in the increase of atretic ratio of preantral and antral follicles, the increase of progesterone concentration in ovarian homogenates, and the low level of testosterone and estradiol. It is suggested that radiation protect the activity of $3{\beta}-HSD$(hydroxysteroid dehydrogenase) and isomerase in the follicular theca cell followed by low level of testosterone and estradiol and thereafter follicular atresia proceed.

• Development and Reproduction
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• v.18 no.4
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• pp.187-195
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• 2014

Polycyclic aromatic hydrocarbons (PAHs), which are ubiquitous in the air, are present as volatile and particulate pollutants that result from incomplete combustion. Most PAHs have toxic, mutagenic, and/or carcinogenic properties. Among PAHs, benzo[a]pyrene (B[a]P) and dimethylbenz[a]anthracene (DMBA) are suspected endocrine disruptors. The testis is an important target for PAHs, yet effects on steroidogenesis in Leydig cells are yet to be ascertained. Particularly, disruption of testosterone production by these chemicals can result in serious defects in male reproduction. Exposure to B[a]P reduced serum and intratesticular fluid testosterone levels in rats. Of note, the testosterone level reductions were accompanied by decreased steroidogenic acute regulatory protein (StAR) and $3{\beta}$-hydroxysteroid dehydrogenase isomerase ($3{\beta}$-HSD) expression in Leydig cells. B[a]P exposure can decrease epididymal sperm quality, possibly by disturbing the testosterone level. StAR may be a key steroidogenic protein that is targeted by B[a]P or other PAHs.

• Toxicological Research
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• v.18 no.3
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• pp.301-309
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• 2002

Licorice has been wed in clinical medicine for thousands of years. However it is only in recent times that we have been able to employ scientific methods to prove its efficacy and to give us a better understanding of its mechanism of action. One of important mechanisms for its efficacy is related to mineralocorticoid activity increased by glycyrrhizic acid, the active ingredient in licorice. Also the main undesirable side-effects of Licorice relate to is mineralocorticoid activity resulting in a state of apparent mineralocorticoid excess (AME). These therapeutic and undesirable effects are explained by the inhibition of 11-$\beta$-hydroxysteroid dehydrogenase (11-$\beta$-HSD) activity. Recently, the reduction of serum testosterone in men by licorice was reported which would have important health implications in the context of fertility and sexual dysfunction. Here, health implication of licorice were reviewed In term of its pharmacodynamic and toxicodynamic mechanism.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.5
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• pp.618-625
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• 2009

The objective of this work was to study the direct effects of daidzein on steroidogenesis in cultured mouse Leydig cells. Adult mouse Leydig cells were purified by Percoll gradient centrifugation, and the cell purity was determined using a $3{\beta}$-hydroxysteroid dehydrogenase ($3{\beta}$-HSD) staining method. The purified Leydig cells were exposed to different concentrations ($10^{-7}$ M to $10^{-4}$ M) of daidzein for 24 h under basal and human chorionic gonadotropin (hCG)-stimulated conditions. The cell viability and testosterone production were determined, and the related mechanisms of daidzein action were also evaluated using the estrogen receptor antagonist ICI 182,780 and measuring the mRNA levels of steroidogenic acute regulatory protein (StAR), cholesterol side-chain cleavage enzyme (P450scc), and $3{\beta}$-HSD-1 involved in testosterone biosynthesis. The results revealed that daidzein did not influence cell viability. Daidzein increased both basal and hCG-stimulated testosterone production in a dose-dependent manner, and this effect was statistically significant at concentrations of $10^{-5}$ M and $10^{-4}$ M daidzein (p<0.05). ICI 182,780 had no influence on daidzein action. RTPCR results revealed that $10^{-5}$ M and $10^{-4}$ M daidzein did not exert any obvious influence on the mRNA level of P450scc in Leydig cells. However, in the presence of hCG, these concentrations of daidzein significantly increased the StAR and $3{\beta}$-HSD-1 mRNA levels (p<0.05), but in the absence of hCG, only $10^{-5}$ M and $10^{-4}$ M daidzein up-regulated the StAR and $3{\beta}$-HSD-1 mRNA expression (p<0.05), respectively. These results suggest that daidzein has direct effect on Leydig cells. Daidzein-induced increase of testosterone production is probably not mediated by the estrogen receptor but correlates with the increased mRNA levels of StAR and $3{\beta}$-HSD-1.

• Korean Journal of Veterinary Research
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• v.59 no.2
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• pp.59-67
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• 2019

We investigated whether ${\beta}$-carotene (${\beta}-CA$) or ellagic acid (EA), originating from various fruits and vegetables, has a preventive effect against male infertility induced by exogenous scrotal hyperthermia. ICR adult mice were intraperitoneally treated with 10 mg/kg of ${\beta}-CA$ or EA daily for 13 days consecutively. During this time, mice were subjected to transient scrotal heat stress in a water bath at $43^{\circ}C$ for 20 min on day 7, and their testes and blood were obtained on day 14 for histopathologic and biochemical analyses. Heat stress induced significant testicular weight reduction, germ cell loss and degeneration, as well as abnormal localization of phospholipid hydroperoxide glutathione peroxidase (PHGPx) and manganese superoxide dismutase (MnSOD) in spermatogenic and Leydig cells. Heat stress also altered the levels of oxidative stress (lipid peroxidation, SOD activity, and PHGPx, MnSOD, and $HIF-1{\alpha}$ mRNAs), apoptosis (Bax, Bcl-xL, caspase 3, $NF-{\kappa}B$, and $TGF-{\beta}1$ mRNAs), and androgen biosynthesis (serological testosterone concentration and $3{\beta}$-hydroxysteroid dehydrogenase mRNA) in testes. These changes were all improved significantly by ${\beta}-CA$ treatment, but only slightly improved by EA treatment. These findings indicate that ${\beta}-CA$, through modulations of oxidative stress, apoptosis, and androgen biosynthesis, is a potent preventive agent against testicular injuries induced by scrotal hyperthermia.

• Journal of Nutrition and Health
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• v.50 no.3
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• pp.217-224
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• 2017

Purpose: Although it is well known thatmortality and morbidity due to cardiovascular diseases are higher in salt-sensitive subjects than in salt-resistant subjects, their underlying mechanisms related to obesity remain unclear. Here, we focused on salt-sensitive gene variants unrelated to monogenic obesity that interacted with sodium intake in humans. Methods: This review was written based on the modified $3^rd$ step of Khans' systematic review. Instead of the literature, subject genes were based on candidate genes screened from our preliminary Genome-Wide Association Study (GWAS). Finally, literature related to five genes strongly associated with salt sensitivity were analyzed to elucidate the mechanism of obesity. Results: Salt sensitivity is a measure of how blood pressure responds to salt intake, and people are either salt-sensitive or salt-resistant. Otherwise, dietary sodium restriction may not be beneficial for everyone since salt sensitivity may be associated with inherited susceptibility. According to our previous GWAS studies, 10 candidate genes and 11 single nucleotide polymorphisms (SNPs) associated with salt sensitivity were suggested, including angiotensin converting enzyme (ACE), ${\alpha}$-adducin1 (ADD1), angiotensinogen (AGT), cytochrome P450 family 11-subfamily ${\beta}$-2 ($CYP11{\beta}$-2), epithelial sodium channel (ENaC), G-protein b3 subunit (GNB3), G protein-coupled receptor kinases type 4 (GRK4 A142V, GRK4 A486V), $11{\beta}$-hydroxysteroid dehydrogenase type-2 (HSD $11{\beta}$-2), neural precursor cell-expressed developmentally down regulated 4 like (NEDD4L),and solute carrier family 12(sodium/chloride transporters)-member 3 (SLC 12A3). We found that polymorphisms of salt-sensitive genes such as ACE, $CYP11{\beta}$-2, GRK4, SLC12A3, and GNB3 may be positively associated with human obesity. Conclusion: Despite gender, ethnic, and age differences in genetics studies, hypertensive obese children and adults who are carriers of specific salt-sensitive genes are recommended to reduce their sodium intake. We believe that our findings can contribute to the prevention of early-onset of chronic diseases in obese children by facilitating personalized diet-management of obesity from childhood to adulthood.

• Biomedical Science Letters
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• v.19 no.3
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• pp.261-265
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• 2013

The corpus luteum is a transient endocrine gland essential for regulation of the ovarian cycle as well as for establishing and maintaining pregnancy. Prostaglandin $F_{2{\alpha}}$ (PGF) initiates functional and structural regression of the corpus luteum and therefore is an important regulator of the estrous cycle. It is a matter of debate whether the endothelial cells of the bovine corpus luteum express PGFR, the cognate receptor for PGF. Therefore, the aim of this study was to assess the expression of PGFR in bovine endothelial cells. Endothelial cells were isolated from the bovine corpus luteum of the mid-luteal stage using magnetic beads and cultured in vitro. We demonstrate that this isolation procedure generates a pure culture of endothelial cells as confirmed by synthesis of Factor VIII and lack of expression of $3{\beta}$-hydroxysteroid dehydrogenase. By RT-PCR, Western blot and immunofluorescence analyses, we further show that the cultured endothelial cells produced PGFR. This model system can be utilized to provide an experimental system to investigate the role of PGF on endothelial cells during the reproductive cycle.