• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2002.11a
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• pp.109-109
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• 2002

In recent reports, the multiple reproductive defects such as cryptorchidism, hypospadias, epididymal cysts, low sperm counts, and testicular cancers are increased in humans, and these changes were doubted by the chemicals with estrogenic or antiandrogenic activities in our environment. To compare the effects of neonatal exposure of di (n-butyl) phthalate and flutamide on the development of reproductive organs and to identify the specific mechanisms of these abnormalities related to the male reproducton, Sprague-Dawley neonate male rats were injected subcutaneously during 5-14 days after birth with corn oil (control), flutamide (0.05, 0.1, and 0.5 mg/animal) and DBP (5, 10, and 20 mg/animal). Animals were killed at 31 (immature) and 42 (pubertal) days of age respectively and blood was collected from abdominal aorta for serum testosterone analysis. Testes, epididymides, seminal vesicles, ventral prostate, levator ani plus bulbocavernosus muscle (LABC), cowpers glands and glans penis were weighed. Expression of steroid hormone receptors (AR and ER) was examined in the testes and ventral prostate. At 31 days of age, ventral prostate, seminal vesicles, LABC, and cowpers glands significantly decreased in the flutamide (0.5 mg/animal) and DBP (20 mg/animal), but serum testosterone levels were not changed. Flutamide slightly delayed the testes descent at the high dose (0.5 mg/animal), but DBP did not show any significant effect on the testes descent at all doses. DBP and flutamide decreased the expression of AR protein in the testes but did not affect the expression of ERa and ER protein in the testes. At 42 days of age, ventral prostate, seminal vesicles, and cowpers glands weights were still significantly decreased at the high dose of flutamide (0.5 mg/animal) and DBP (20 mg/animal), but the weights of testes and epididymides were not different. Serum testosterone decreased significantly in DBP treated animals and slightly, not significantly, in flutamide group. While DBP still significantly decreased the expression of AR protein in testis, flutamide recovered from downregulation of AR protein and did not affect the expression of ERa and ER protein in the testes. Based on these results, flutamide and DBP have shown several similar patterns in reproductive abnormalitis, but some marked differences which may be caused by different acting mechanism.

• Development and Reproduction
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• v.20 no.3
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• pp.237-245
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• 2016

Direct communication between neighboring cells via gap junction in tissue is important for maintenance and regulation of its physiological functions. Each epididymal region has different composition of cell types. It is well recognized that the epididymis is a steroid hormone-responsive tissue. The present study was designed to determine the effect of estradiol benzoate (EB) or flutamide exposured at the early postnatal age on the expression of connexin (Cx) isoforms in the caudal epididymis. The EB or flutamide was subcutaneously administrated to male Spragure Dawley rat at 7 days of age, and expressional changes of Cx isoforms in the adult corpus epididymis were determined by quantitative real-time PCR. The treatment of low-dose EB resulted in decreases of Cx30.3, Cx31.1, Cx37, and Cx45 expression but caused an increase of Cx32 expression. Exposure to high-dose EB led into expressional increases of Cx31, Cx31.1, Cx32, Cx40, and Cx43, even though a decrease of Cx37 expression was found with a high-dose EB treatment. A low-dose flutamide induced increases of Cx31, Cx31.1, Cx32, and Cx43 expression but a decrease of Cx37 expression. Expression of most Cx genes were significantly increased by a high-dose flutamide, while no expressional change of Cx26 and Cx40 was detected by a high-dose flutamide. These results indicate that expression of Cx isoforms in the caudal epididymis is altered by exposure to steroidal compounds at the prepubertal age. It is suggested that a contact with environmental exogenous materials during the early postnatal period would lead to alteration of epididymal functions at the adult.

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 2002.10a
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• pp.168-168
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• 2002

To establish a test protocol for the rodent 20-day thyroid/pubertal assay, flutamide and diethylstilbestrol (DES) were administered to intact male Sprague-Dawley rats from postnatal day 33 for 20 days. Flutamide (1, 5, and 25 mg/kg/day) or DES (10, 20, and 40 ug/kg/day) was given once daily by oral gavage to immature male rats. Prepuce separation was significantly delayed in flutamide group and in DES group. One day after the last dose, the rats were killed and pituitary, thyroid, and reproductive organs were removed and weighed. Flutamide treatment resulted in a significant reduction in the weights of epididymides, ventral prostate, seminal vesicles plus coagulating glands and fluid (SVCGF), levator ani. bulbocarvenus muscles (LABC), Cowper's glands, and glans penis. The weight of adrenal glands decreased at % mg/kg/day, while testes and any other organ weights were unaffected. No microscopic changes were observed in the thyroid glands. Serum levels of testosterone wert significantly increased in the flutamide-treated groups and serum levels of estradiol were also increased. A significant reduction in the weights of testes, epididymides, ventral prostate, SVCGF, LABC, Cowpers glands, and glans penis of DES treated group. Serum testosterone and LH decreased significantly in DES group. Decrease of estradiol was observed, but not significant. These results indicate that flutamide and DES delay puberty in the male rat and its mode of action appears to be via altered secretion of steroids, which subsequently affect the development of the reproductive tract. (Supported by the grant from NITR/Korea FDA for Endocrine Disrupter Research.)

• Toxicological Research
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• v.16 no.2
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• pp.163-172
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• 2000

Recently, there is a worldwide concern that a great number of man-made chemicals have a hormone-like action both in humans and in animals. DECD is developing screening programs using validated test systems to determine whether certain substances may have an effect in humans. In the present study. the establishment oj repeated-dose toxicity test method was tried. Flutamide. an anti-androgenic agent. was administered by gavage to Sprague-Dawley rats for 28 days at dose levels of 0. 0.5. 3 and 18 mg/kg body weight (10-15 rats/sex/group) to examine the effects on general findings. especially reproductive and endocrine parameters. Clinical signs. body weights, food consumption, and sexual cycle were checked and measured. For the gross and microscopic examinations. 10 rats/sex/group were sacrificed at the end of dosing period and the remaining animals of control and high dose groups (5 each) were sacrificed after 14 days recovery. Examinations for hematology and clinical chemistry were carried out at necropsy. There were no treatment-related changes in clinical signs. body weights, food consumption. gross necropsy. hematology and clinical chemistry at all doses of both sexes. The period and regularity of sexual cycle were not adversely affected at all doses by the test agent. At 18 mg/kg. both decreased weights of prostate, seminal vesicle and epididymis in males and increased weights of spleen and thymus in females were observed. In addition, decreased number of spermatids and sperms. increased serum testosterone concentration and increased incidence (100%) of interstitial cell hyperplasia were seen in males. At 18 mg/kg of the recovery group. decreased prostate weight. reduced sperm count and increased incidence (20%) of interstitial cell hyperplasia in males and increased thymus weight in females were observed. At 3 mg/kg. reduced sperm count was found. There were no adverse effects on parameters examined at 0.5 mg/kg of both sexes. The results suggested that the potential target organs of flutamide may be accessory sexual glands including testes for males and spleen and thymus for females. Taken together. this test method was found to be a useful screening test system for endocrine disrupting chemicals.

• Korean Journal of Food Science and Technology
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• v.46 no.4
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• pp.516-521
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• 2014

The mechanisms underlying the refractory effects of flutamide, a first-line oral anti-androgen drug, have not been entirely elucidated. In the present study, we investigated the mechanism of flutamide-induced hormone-refractory prostate cancer cell growth and its modulation by resveratrol, a phytoalexin present in grapes. Resveratrol significantly attenuated interleukin 6 (IL-6)-induced signal transducer and activator of transcription 3 (STAT3) transcriptional activity and dihydrotestosterone (DHT) or IL-6-induced prostate-specific antigen (PSA) transcriptional activity. Furthermore, compared to treatment with DHT or IL-6 alone, combination treatment of cells significantly increased PSA transcriptional activity, and resveratrol markedly diminished DHT plus IL-6-induced STAT3 and PSA transcriptional activities. Thus, the inhibitory effects of resveratrol on IL-6-, DHT-, and flutamide-induced hormone-refractory prostate cancer cell growth are partly mediated by the suppression of STAT3 reporter gene activity, suggesting that resveratrol represents a promising therapy for prostate cancer.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2003.02a
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• pp.9-9
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• 2003

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2003.10a
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• pp.181-181
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• 2003

• Proceedings of the Korean Society of Toxicology Conference
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• 2001.05a
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• pp.147-147
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• 2001

To establish a test protocol for the rodent 20-day thyroid/pubertal assay, we dosed flutamide(fl), a non-steroidal androgen antagonist to intact male SD rats from postnatal day 33 for 20 days, and examined several reproductive endpoints for assessing the sensitivity of a list of parameters for detecting endocrine-related effects of endocrine-disrupting chemicals.(omitted)

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.187-187
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• 2003

The aims of present study were to compare the effects of in utero exposure to diethylstibestrol (DES), di(n-butyl)phthalate (DBP) and flutamide on the development of reproductive organs and to investigate the specific mechanisms of these abnormalities in the male reproductive system.During gestation days 10-19, pregnant Sparague-Dawley (SD) female rats were administered orally with corn oil (control), DES (25, 50, or 100 ${\mu}$/kg/day), (omitted)

• Proceedings of the Korean Society of Toxicology Conference
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• 2003.10b
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• pp.181-181
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• 2003

The aims of present study were to compare the effects of in utero exposure of several chemicals which have antiandrogenic characteristics on the development of reproductive organs and to investigate the specific mechanisms related to the abnormalities observed in the male reproductive system.(omitted)