• The Korean Journal of Physiology and Pharmacology
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• v.3 no.2
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• pp.215-222
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• 1999

Nonylphenol (NP) is a widespread environmental pollutant that has been shown to exert both toxic and estrogenic effects on mammalian cells. As the effects of NP on the reproductive system of adult male vertebrates are virtually unknown, we investigated not only the changes of reproductive hormone secretion in serum after chronic exposure to NP but also, in order to identify the site of its action, the reproductive hormone secretion in serum 48 hours after microinfusion of NP within hypothalamic preoptic area (POA). In the chronic exposure, the luteinizing hormone (LH), follicle stimulating hormone (FSH), and testosterone in serum were decreased but prolactin (PRL) concentrations were increased. The LH, FSH, and testosterone in serum were decreased through the direct infusion of NP into POA, while there was no difference in mean serum prolactin between NP and control groups. These observations suggest that NP as endocrine disruptor has modulatory effects on hypothalamo-pituitary-gonadal axis and that the site of action of NP could be hypothalamic POA.

• Journal of Pharmaceutical Investigation
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• v.39 no.1
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• pp.37-41
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• 2009

The purpose of this study was to compare the efficacy of Lorelin Depot $Injection^{(R)}$ (Dongkook Pharm. Co., LTD) with Lucrin Depot $Injection^{(R)}$ (Abbott) by measuring serum testosterone level in rats. Leuprorelin (leuprolide acetate), which is an active compound for the two formulations, is an LHRH analogue that is used for the treatment of a wide range of sex hormone-related disorders including advanced prostatic cancer, endometriosis and precocious puberty. Lorelin Depot $Injection^{(R)}$ is a micro-encapsulated formulation to suppress testosterone level by releasing leuprorelin continuously for four weeks with a single subcutaneous injection. The comparison study of the efficacy was performed during four weeks, and serum testosterone levels were monitored in the two formulations. The mean serum testosterone levels from the formulations were decreased to that of the castrate range (50 ng/dL or less) after three days after the initial depot injection, and the concentration were remained throughout four weeks' period. There were no significant differences in the $AUC_{0-3day}$ of testosterone and testosterone levels at 3, 7, 14, 21 and 28 days between the two formulations. These results indicate that the two formulations, Lorelin Depot $Injection^{(R)}$ and Lucrin Depot $Injection^{(R)}$, are bioequivalent in terms of the serum testosterone level in rats.

• Biomolecules & Therapeutics
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• v.18 no.3
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• pp.257-261
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• 2010

While it's been shown that arsenic impairs male reproductive function, it remains unclear whether the mechanism involves an effect on testosterone (T) production. We examined plasma T and luteinizing hormone (LH) levels in mice given water containing either 20 or 40 mg/L sodium arsenite (SA). The plasma T levels were lower in SA-treated mice than in controls and correlated well with testicular T levels within individuals. However, SA treatment did not significantly affect plasma LH levels. The ratio of plasma T to LH was reduced by the treatment with 40 mg/L SA. These results suggest arsenic-induced defect in testicular testosterone production in mice.

• Korean Journal of Psychosomatic Medicine
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• v.8 no.1
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• pp.65-71
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• 2000

Objects : Aimed to test the hypothesis that neonatal testosterone exposure in female mice influences the development of testosterone-related pain inhibitory system and that testosterone administered in adulthood decreases the pain sensitivity. Methods : Thirty androgenized(testosterone propionate $100{\mu}g$ ip within 24 hrs after birth) adult female and twenty five control(normal saline $100{\mu}g$ ip within 24 hrs after birth) adult female mice were injected with testosterone propionate 1mg/kg/day for 3 consecutive days from 84th experimental days. Nociceptive sensitivity was measured before and after treatment of testosterone by tail flick latency on 84th and 86th experimental days. Results : 1) On the 84th experimental day, basal nociceptive sensitivity was significantly higher in the androgenized group($2.7{\pm}0.4$ sec) as compared to the control group($3.3{\pm}1.1$ sec). 2) Testosterone treatment on the 84th experimental day significantly lowered nociceptive sensitivity in both androgenized($5.2{\pm}0.9$ sec) and control groups($4.6{\pm}1.8$ sec). However the effect was significantly greater in the androgenized group. 3) Nociceptive sensitivity on 86th experimental day before administration of testosterone was significantly lower in the androgenized group($4.8{\pm}1.9$ sec) as compared to the control group($3.9{\pm}1.2$ sec). 4) Testosterone treatment on the 86th experimental day significantly lowered the nociceptive sensitivity in both groups, but the androgenized group($5.9{\pm}0.9$ sec) showed significantly lower post-treatment nociceptive sensitivity as compared to the control group($4.9{\pm}1.5$ sec). 5) Nociceptive sensitivity was decreased significantly after injection of testosterone once a day for two consecutive days in the androgenized group(${\Delta}2.1{\pm}1.0$ sec), but not in the control group(${\Delta}0.5{\pm}1.3$ sec). Conclusions : There may be a testosterone-related pain inhibitory system, the development of which is enhanced by exposure to testosterone in the neonatal period, and the activity of which is also mediated by testosterone in the later life.

• Korean Journal of Agricultural Science
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• v.43 no.5
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• pp.742-749
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• 2016

Boar taint, an unpleasant odor of pork, is associated with two substances including androstenone and skatole. Testosterone is a steroid hormone as well as a strong predictor for androstenone secretion. Isoflavones of soy origin play a role in modulating the metabolism of sex hormones. Although several methods responsible for reducing boar taint are under investigation, the precise mechanism by which isoflavones reduce testosterone has not yet been identified. The objective of the current study was to investigate the effects of isoflavones extracted from a soy by-product on the concentration of serum testosterone in mouse. A total of 24 mice were supplemented with basal diet (control), daidzin plus genistin mix (T1), or isoflavone extracts (T2). After 11 days of treatment, size and weight of testis, as well as the concentration of sex hormones, including testosterone and estrogen, were analyzed. There was no difference in size or weight of testis from mice among control, T1, and T2. Serum testosterone levels were significantly decreased (p < 0.05) both in T1 and T2 when compared with the control group. Furthermore, estrogen concentration in blood was increased (p < 0.05) in T2 (numerically increased in T1) compared with the control group. Taken together, the use of isoflavones extracted from soy by-products would be a plausible strategy for reducing testosterone level, ultimately reducing boar taint without castration of piglets.

• YAKHAK HOEJI
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• v.57 no.4
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• pp.241-249
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• 2013

We reported previously that the extracts of Yacon tuber and leaf have spermatogenic activity and testosterone level increasing effect in men. The aim of this study was to investigate the mechanism of testosterone level increasing effect of Yacon tuber and leaf extracts. In this study, we found that Yacon leaf extracts and chlorogenic acid, a constituent of Yacon extracts showed significantly inhibition effect of testosterone degradation in rat liver homogenate. We suggest that this could be a part of direct mechanism about increasing effect of testosterone level. Futhermore, we evaluated the inhibition effect of testosterone metabolism of Torilis japonica and Coix lacryma-jobi have been reported as $5{\alpha}$-reductase inhibitor. The inhibition ratio of testosterone metabolism of these were Torilis japonica>Coix lacryma-jobi>Yacon. We also evaluated the benign prostatic hyperplasia (BPH) score with the preparation composed of these natural product, Yacon pill. It showed the decreased the BPH score in men. Rats with BPH showed significantly increased dihydrotestosterone (DHT) levels in the serum; however, Yacon pill extracts treated rats showed significant reduction of DHT levels compared with the BPH group. Conclusively, Yacon pill showed the possibility as ameliorable agents of BPH symptoms.

• Environmental Analysis Health and Toxicology
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• v.18 no.2
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• pp.95-100
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• 2003

Dichlorodiphenyltrichloroethane (DDT), is a widespread environmental pollutant. In this study, we investigated the effect of DDT on testosterone production through aromatase and investigated its molecular mechanism in testicular leydig cell, R2C. We investigated that the effects of DDT on testosterone production and its effects on aromatase activity in R2C cell by radio immunoassay (RIA). As the results, the potent leyding cell activator LH increased testosterone production compared to the control. DDT exposure significantly decreased testosterone production in R2C cell and DDT alone affected T reduction in a dose-dependent manner in R2C cell slightly. In addition, DDT was found to increase aromatase activity in R2C cell in a dose dependent manner. In order to assess whether the suppressive effects of DDT on LH-inducible testosterone production might be influenced by the ER, ICI 182.780, a pure antiestrogen, was used, and it was found that these inhibitory effects of DDT were antagonized by ICI 182.780, implying that the ER mediates the suppressive effects of DDT. Furthermore, the inducible effects of DDT on aromatase might be influenced by the ER, ICI 182.780 was used, and it was found that these enhancing effects of DDT were antagonized by ICI 182.780, implying that the ER mediates the inducible effects of DDT. Our results indicated that DDT inhibition of LH-inducible testosterone production in R2C is mediated through aromatase. However, the precise mechanisms by which DDT enhance in leyding cell remains unknown. The current study suggests the possibility that DDT might act as a modulator aromatase gene transcription.

• Journal of Applied Biological Chemistry
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• v.59 no.4
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• pp.305-311
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• 2016

This study investigated the effects of a mixture of fenugreek seeds and Lespedeza cuneata extracts on testosterone synthesis in TM3 cells that were oxidatively stressed with $H_2O_2$. In order to oxidatively stress TM3 cells, the cells were treated with $50{\mu}M$ hydrogen peroxide for 4 hr in serum-free media. Yagwanmun-horopa mixture (YHM) showed neither cytotoxicity nor increment of cell proliferation in the oxidatively stressed TM3 cells in any concentration. When the cells were treated with hydrogen peroxide, testosterone levels decreased, but the testosterone level was returned to that of the control level in the presence of YHM. In order to find out the reasons for the increase of testosterone, the expression of the genes involved in the synthesis or disintegration of testosterone. On the other hand, the levels of $3{\beta}$-HSD4 and 17, 20-desmorase, which are involved in testosterone synthesis, were decreased through the use of hydrogen peroxide and were recovered through YHM treatment. Aromatase and $5{\alpha}$-reductase2, which convert testosterone to estradiol and dihydrotestosterone, respectively, were increased through the use of hydrogen peroxide, and were returned to control level through YHM treatment. These results suggest that YHM does not affect TM3 cell proliferation. However, YHM increases the expression of testosterone-synthesizing enzyme, which was decreased through oxidative stress, and decreases the expression of testosterone- converting enzyme, which was increased through oxidative stress. Therefore, it is reasonable that YHM has strong recovery activity on testosterone to normal level, even in the oxidatively stressed TM3 cells which mimics the andropause state.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2003.10a
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• pp.67-67
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• 2003

Tributyltin chloride (TBTCI) is an organotin compounds that have been widely used as antifouling agents and bioaccumulated in the food chain. TBTCI has been known to induce imposex in female gastropods. There are several reports that TBTCI increased testosterone level and inhibited the conversion of testosterone to estradiol by the aromatase cytochrome P450 enzyme. In this studies, we investigated the effects of TBTCI on steroidogenesis in testes, We dosed to 4-week-old Spragus-Dawleys (SD) male rats with TSTCI (0, 1, 5, 10, and 20mg/kg/day) daily by gavage for 14 days. TBTCI significantly decreased the weights of seminal vesicle, prostate, cowper's gland and LABC at 10 and 20mg/kg/day but significantly Increased the weights of liver at 10 and 20mg/kg/day and adrenals at 20mg/kg/day. mRNA levels of steroidogenic acute regulatory (StAR) and P450 aromatase were decreased and mRNA levels of cytochrome P450 17$\alpha$-hydroxylase/$C_{17-20}$ lyase (P450c17) were increased by TBTCI. TBTCI significantly increased serum testosterone level in dose-dependent manner. From above results, we found that TBTCI altered mRNA levels of enzymes related steroidogenesis, weights of organs and serum testosterone levels. This suggests that change of hormone levels may be due to alteration of mRNA levels of steroidogenic enzyme in testes, but further studies are necessary to investigate hormone levels in testis organ in order to find a relation of enzyme related to steroidogenesis with hormone levels. This work was supported by the Korea FDA Grant KFDA-03131-EDS-010.

• The Korean Journal of Zoology
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• v.31 no.1
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• pp.35-48
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• 1988

This study was made to investigate the effect of testosterone and cyclic-AMP (cAMP) on rat epididymis. Peritoneai injections of testosterone and cAMP to rats were earned out The activities of acid phosphatase (ACP), alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) were measured and ultrastructural changes of luminal epithelial cells were observed. As a result, the activity of ACP was significanily decreased on the third day, that of ALP on the fifth day and that of LDH on the seventh day respectively in castrated group. In addition, the activities of ACP and ALP were significanily increased when treated with testosterone for 5 days, that of LDH when treated with testosterone for 7 days. In case of cAMP and cAMP - theophylline injection, the activities of ACP and LDH were increased but the range of increase was of no significance. However a significant increase in the activity of ALP was seen on both cases. On electron microscopic examination, gradually deformed Golgi complex, destructed mitochondria and disrupted stereociha were observed in castrated group. In case of testosterone injection, disrupted Golgi complex, mitochondria and stereocilia showed recovery. When cAMP and cAMP-theophylline were injected as an alternative, various cytoplasmic organelles as well as Golgi com- plex were recovered but stereocilia remained unrecovered.