• Animal Bioscience
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• v.37 no.1
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• pp.50-60
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• 2024

Objective: Testicular fat deposition has been reported to affect animal reproduction. However, the underlying mechanism remains poorly understood. The present study explored whether sperm meiosis and testosterone synthesis contribute to mouse testicular fat deposition-induced reproductive performance. Methods: High fat diet (HFD)-induced obesity CD1 mice (DIO) were used as a testicular fat deposition model. The serum hormone test was performed by agent kit. The quality of sperm was assessed using a Sperm Class Analyzer. Testicular tissue morphology was analyzed by histochemical methods. The expression of spermatocyte marker molecules was monitored by an immuno-fluorescence microscope during meiosis. Analysis of the synthesis of testosterone was performed by real-time polymerase chain reaction and reagent kit. Results: It was found that there was a significant increase in body weight among DIO mice, however, the food intake showed no difference compared to control mice fed a normal diet (CTR). The number of offspring in DIO mice decreased, but there was no significant difference from the CTR group. The levels of follicle-stimulating hormone were lower in DIO mice and their luteinizing hormone levels were similar. The results showed a remarkable decrease in sperm density and motility among DIO mice. We also found that fat accumulation affected the meiosis process, mainly reflected in the cross-exchange of homologous chromosomes. In addition, overweight increased fat deposition in the testis and reduced the expression of testosterone synthesis-related enzymes, thereby affecting the synthesis and secretion of testosterone by testicular Leydig cells. Conclusion: Fat accumulation in the testes causes testicular cell dysfunction, which affects testosterone hormone synthesis and ultimately affects sperm formation.

• YAKHAK HOEJI
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• v.35 no.4
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• pp.295-300
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• 1991

Ralationship between noradrenergic nervous system activity and luteinizing hormone releasing hormone(LHRH) content mediated by testosterone in hypothalamus was tested. Three groups of adult male animals were prepared; (1) Intact; (2) Castration+Vehicle (Cast+V); (3) Castration+Testosterone (Cast+T). Silastic capsule containing vehicle or testosterone was implanted into neck region of animals two weeks following castration. Norepinephrine content, alpha-adrenergic receptor binding characteristics using H$^{3}$-WB4101, and content of LHRH by LHRH RIA procedure were determined. Testosterone replacement to castrated male rats augmented the content of norepinephrine and LHRH. Testosterone replacement increased the alpha-adrenergic receptor density but did not change alpha-receptor affinity. The data from the present study suggest that increase in LHRH content by testosterone may be positively coupled to the activity of central noradrenergic nervous system.

• The Korean Journal of Nuclear Medicine
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• v.16 no.2
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• pp.37-47
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• 1982

To evaluate fetal sex-hormonal status before delivery, testosterone and follicle stimulating normone(FSH) levels were measured in 64 amniotic fluid samples at midgestation by radioimmunoassay method. The mean concentration of testosterone in amniotic fluid of 37 cases carrying male fetus was 90.7 pg/ml and 27 cases carrying female fetus was 62.3 pg/ml. The mean :amniotic fluid FSH concentration of male fetus was 1.15 mIU/ml and of female fetus was 11.98 mIU/ml. The amniotic fluid testoserone and FSH concentrations had statistical difference between male and female fetuses. The ratio of testosterone over FSH in the amniotic fluid was 231.2 in male, 9.8 in female respectively and very significant difference was noticed. The levels of testosterone/FSH greater than 25 were found over 92% of male fetus and lesser than 25 were found over 92% female fetus. Measurement of testosterone and FSH especially testosterone/FSH ratio in amniotic fluid in midgestation may be an adjunct to other method of fetal sex determination.

• 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.

• The Korean Journal of Physiology and Pharmacology
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• v.19 no.3
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• pp.235-240
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• 2015

Androgen receptor (AR) signaling is important for prostate cancer (PCa) cell proliferation. Here, we showed that proliferation of hormone-sensitive prostate cancer cells such as LNCaP was significantly enhanced by testosterone stimulation whereas hormone-insensitive prostate cancer cells such as PC3 and VCaP did not respond to testosterone stimulation. Blocking of AR using bicalutamide abolished testosterone-induced proliferation of LNCaP cells. In addition, knockdown of AR blocked testosterone-induced proliferation of LNCaP cells. Basal expression of low-density lipoprotein receptor-related protein 6 (LRP6) was elevated in VCaP cells whereas stimulation of testosterone did not affect the expression of LRP6. However, expression of LRP6 in LNCaP cells was increased by testosterone stimulation. In addition, knockdown of LRP6 abrogated testosterone-induced proliferation of LNCaP cells. Given these results, we suggest that androgen-dependent expression of LRP6 plays a crucial role in hormone-sensitive prostate cancer cell proliferation.

• Journal of environmental and Sanitary engineering
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• v.21 no.2 s.60
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• pp.30-35
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• 2006

The purpose of this study finds out the effect of red ginseng extract (1.0g/kg) on TBTO (10, 20, and 40mg/kg) which poisons against some organs like thyroids gland, liver, kidney, testis, ovary, sex hormone activity of rats are examined by gastric tubing for 3 weeks. The weight of each organ in treated group were increased, especially liver in female and those of testis in males were significantly increased at 10, 20 and 40mg/kg (P<0.05, P<0.01). In case of sex hormone activity of each sex, the estradiol activity of female and testosterone activity of males were significantly decreased rather than the control group (P<0.05, P<0.01) According to between the TBTO treated group and 10+ rGe group of the testosterone activity each sex were significantly increased (P<0.01).

• Sleep Medicine and Psychophysiology
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• v.6 no.2
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• pp.116-125
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• 1999

Objectives: The purpose of this study is to investigate the effect of exercise load on sleep structure and stress hormone secretion during sleep. Methods: Five male physical education students were included in this study after giving their written, informed consents in the Research Institute for Sports Science at the University of Hanyang. All subjects have performed for at least 3 years in a regular aerobic exercises such as football, basketball, and running. The subjects were divided into three groups ; NOE(non-exercise), MDE(middle duration exercise), LDE(long duration excercise). MDE group maintained a total of 120 min exercise, and LDE group maintained a total of 300 min exercise by football, basketball or badminton. All subjects were acclimatized to the experimental sleep condition by spending one night under expermental conditions, including the placement of an intravenous catheter. During the subsequent night(24:00-08:00), somnopolygraphic sleep recordings were obtained, and blood for measuring growth hormone, cortisol, testosterone, and $\beta$-endorphin was collected every 120 min throughout the night. Blood samples were obtained from prominent forearm veins of subjects. Then, the samples were immediately placed in ice and centrifuged within 10 min at 3000 rpm at $4^{\circ}C$. Statistical analyses were performed using the SPSS/$PC^+$. Data were analyzed by one-way ANOVA with repeated measures. Results: No significant differences among groups were observed in sleep latency, total sleep time, stage 2 sleep, and slow wave sleep. However, daytime exercise produced significant changes in stage 1 sleep, REM sleep, stage 2 sleep latency, REM sleep latency and sleep efficiency. Stage 1 sleep, stage 2 sleep latency, and REM sleep latency significantly increased in LDE compared to those of NOE and MDE groups. But the amount of REM sleep significantly decreased in LDE. Sleep efficiency of MDE was higher than those of NOE and LDE. The blood concentrations of growth hormone, testosterone, and cortisol during night sleep were significantly lower in LDE than in NOE. $\beta$-endorphin concentrations in blood during night sleep were not different among groups. Conclusion: The daytime exercise load was significantly related to sleep structure and stress hormone secretion during night sleep. Long duration exercise showed a harmful effect on sleep structure and hormone secretion. However, middle duration exercise had a beneficial effect on sleep structure and hormone secretion during sleep.

• 대한생식의학회:학술대회논문집
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• 1996.06a
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• pp.40-57
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• 1996

• Molecular & Cellular Toxicology
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• v.4 no.3
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• pp.230-234
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• 2008

Epidemiological studies demonstrate an adverse effect of several environmental and occupational exposures on male sex hormone. Bisphenol A (BPA) is a weak estrogen and a widely used industrial chemical. Epoxy resin painters may be continuously exposed to BPA at high concentrations. The effect of occupational exposure of BPA on male reproduction was examined by measuring the urinary BPA, testosterone and gonadotropic hormones of epoxy resin painters in the shipyard. The painters had significantly higher concentrations of urinary BPA (2.61${\pm}$1.08 ${\mu}g$/g creatinine) than controls (1.38${\pm}$0.5 9 ${\mu}g$/g creatinine). In serum, the testosterone level of painters was significantly decreased but the luteinizing hormone (LH) and follicle-stimulating hormone (FSH) levels of painters were significantly higher than controls. Occupational exposure to BPA influences testosterone and gonadotropic hormones in male workers.

• Development and Reproduction
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• v.16 no.4
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• pp.235-251
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• 2012

The reproductive activity in male mammals is well known to be regulated by the hypothalamus-pituitary-gonad axis. The hypothalamic neurons secreting gonadotropin releasing hormone (GnRH) govern the reproductive neuroendocrine system by integrating all the exogenous information impinging on themselves. The GnRH synthesized and released from the hypothalamus arrives at the anterior pituitary through the portal vessels, provoking the production of the gonadotropins(follicle-stimulating hormone (FSH) and luteinizing hormone (LH)) at the same time. The gonadotropins affect the gonads to promote spermatogenesis and to secret testosterone. Testosterone acts on the GnRH neurons by a feedback loop through the circulatory system, resulting in the balance of all the hormones by regulating reproductive activities. These hormones exert their effects by acting on their own receptors, which are included in the signal transduction pathways as well. Unexpected aberrants are arised during this course of action of each hormone. This review summarizes these abnormal phenomena, including various mutations of molecules and their actions related to the reproductive function.