• 한국환경보건학회지
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• 제50권3호
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• pp.201-211
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• 2024

Background: Organic ultraviolet (UV) filters are widely used in sunscreen products and have been identified as an emerging contaminant. Organic UV filters co-exist with multiple components, but their mixture toxicity remains largely unknown. Objectives: We investigated the toxicity of single and binary mixtures of commonly used UV-filters using the human adrenocarcinoma (H295R) cell line. Methods: After exposure to non-cytotoxic concentrations of avobenzone (AVO), homosalate (HS), octisalate (OS), octinoxate (OMC), and octocrylene (OC), the levels of testosterone (T) and 17β-estradiol (E2) were measured. The median effective concentration (EC₅₀) values for the E2 of the individual substances were used to determine the mixture effect of four binary combinations: OMC+AVB, OMC+HS, OMC+OS, and OMC+OC. The synergistic, additive, and antagonistic effects of the mixture were determined by calculating toxic units (TU). To examine the mechanism of mixture toxicity, eight genes involved in steroidogenesis were analyzed using the real-time polymerase chain reaction. Results: The significant increase in E2 in H295R cells exposed to AVO, HS, OS, OMC, and OC suggest an estrogenic effect of the tested UV-filters. A significant decrease in T was observed in cells exposed to HS and OS. EC₅₀ values for E2 increase were 105 nM for AVO, 110 nM for HS, 120 nM for OS, 55 nM for OMC, and 80 nM for OC. Both binary mixtures consisting of OMC+HS and OMC+OS have synergistic effects. Conclusions: Our results showed that five types of UV-filter substances increase E2 in H295R cells. We examined the mixture toxicity in terms of increased estrogenicity and confirmed that E2 significantly increased when OMC was mixed with a salicylate-based UV-filters. These findings highlight the importance of determining the impact of UV filter mixtures.

• 한국발생생물학회지:발생과생식
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• 제27권4호
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• pp.185-193
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• 2023

Although increasing evidence of cause-and-effect relationship between BPA exposure and female reproductive disorders have been suggested through many studies, the precise biochemical and molecular mechanism(s) by which BPA interferes with steroidogenesis in the ovarian cells still remain unclear. Therefore, the purpose of this study was to discover the steroidogenic biomarker(s) associated with BPA treatment in human granulosa cell line, KGN. In this study, our results obtained via the analysis of steroidogenesis-related protein expression in KGN cells using quantitative polymerase chain reaction (qPCR) and western blot analyses revealed that the expression levels of steroidogenic acute regulatory (StAR) and aromatase decreased considerably and gradually after BPA treatment in a dose-dependent manner under BPA treatment. Further, remarkable decreases in their expression levels at the cellular levels were also confirmed via immunocytochemistry, and subsequent StAR and aromatase mRNA expression levels showed profiles similar to those observed for their proteins, i.e., both StAR and aromatase mRNA expression levels were significantly decreased under BPA treatment at concentrations ≥0.1 μM. We observed that follicle stimulating hormone upregulated StAR and aromatase protein expression levels; however, this effect was suppressed in the presence of BPA. Regarding the steroidogenic effects of BPA on KGN cells, controversies remain regarding the ultimate outcomes. Nevertheless, we believe that the results here presented imply that KGN cells have a good cellular and steroidogenic machinery for evaluating endocrine disruption. Therefore, StAR and aromatase could be stable and sensitive biomarkers in KGN cells for the cellular screening of the potential risk posed by exogenous and environmental chemicals to female reproductive (endocrine) function.

• 한국가축번식학회지
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• 제19권2호
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• pp.141-145
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• 1995

The effect of splenectomy on the concentration of progesterone in pregnant wistar rats showing 4-day regular estrous cycles more than two cycles were investigated. The day after mating with the same male animal was designated day 0 of pregnancy. Splenectomy was conducted on day 0 (early-S), 6 (middle-S) and 13 (late-S) of pregnant rat, respectively. Blood sample were collected at day 1, 7, 14 and 21 of pregnancy. Concentraton of serum progesterone was determined by emzyme-linked immunosorbent assay (ELISA) using specific antibodies and emzyme conjugate(progesterone peroxidase labeled). In normal pregnant rats, serum progesterone concentrations were increased significantly (P<0.05) on day 7 and 14 of pregnancy compared with on day 1 of pregnancy and then dramatically decreased on day 21. However in early and middle splenectomized rats, progesterone concentrations were significantly (P<0.05) decreased on day 7 and 14 of pregnancy compared with same day of normal rats. These observations indicate that luteotropic action and steroidogenesis by corpus luteum of ovary may be regulated by splenocytes in rat.

• Mass Spectrometry Letters
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• 제5권2호
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• pp.35-41
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• 2014

Gas chromatography-mass spectrometry (GC-MS) methods have been used extensively in clinical steroid analyses. Evaluating the metabolic ratios of precursors to products by accurate quantification of individual steroid levels in biological samples can reveal the activities of enzymes associated with steroid metabolism. This review article discusses the impact of GC-MS-based steroid profiling on our understanding of the biochemical role of steroids and their metabolic enzymes in hormone-dependent diseases, such as congenital adrenal hyperplasia (CAH), cortisol-mediated hypertension, apparent mineralocorticoid excess (AME), male-pattern baldness, and breast and thyroid cancers. Steroid profiling is a comprehensive analytical technique that can be applied whenever the highest specificity is required and may be a reasonable initial diagnostic approach.

• 한국환경독성학회:학술대회논문집
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• 한국환경독성학회 2003년도 춘계학술대회
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• pp.178-179
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• 2003

The testis is composed of four cell types like supporting cells, steroid-producing cells, connective tissue cells and germ cells. Apoptosis is a common phenomenon during spormatogenesis. Apoptosis of germ cells can also be induced by exposure to radiation. Previous studies have shown that most types of germ cells are rather radiosensitive while somatic cells in testis are much more radio-resistant. The somatic cells in testis are divided to mainly Sertoli and Leydig cells. Though somatic cells are more radio-resistant than germ cells, radiation can induce the impairment of their function. This damaged function of somatic cells may accelerates degeneration of germ cell indirectly. Tn the present study, we have examined the apoptotic effect of mouse testis and irradiation effect of steroidogenesis of Leydig cells after irradiation.

• 한국수정란이식학회지
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• 제5권2호
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• pp.1-10
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• 1990

The individual difference of superovulatory responses and inferior embryo quality in superovulated cattle may cause disturbances in the endocrine profile, follicular steroidogenesis, nuclear maturation of nocyte, fertilization and cleavage of embryos. However, the reasons why those disturbances are occurred were not understood. The methods of the improvement of superovulatory response and embryo production were the use of anti-PMSG if PMSG used, pure FSH or controlled FSH-LH inducer, priming dose of gonadotropin in the first few day of the estrous cycle and GnRH or analogue. However, all of the above methods were not reduced the individual differences but improved embryo production We must continue the fundamental studies to understand the mechanism.

• Clinical and Experimental Reproductive Medicine
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• 제15권1호
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• pp.1-9
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• 1988

The contraception practice rate in Korea has steadily increased from 9% in 1964 to 72% in 1987. Accordingly, natural increase rate of population declined from 28.4 per 1,000 in 1964 to 12.4 per 1,000 in 1987. Notably in recent years, the acceptance of surgical contraception services has sharply increased in this country. Now the author analyzes various factors influencing successful vasectomy and vasovasostomy based on his experience in performing more than 8,000 vasectomies and 1,000 vasovasostomies during the past 25 years. These various factors consist of preoperative screening interview, surgical vasectomy technique, vas irrigation technique, open-ended vasectomy, complications from vasectomy, sperm granuloma formation, spermatogenesis and steroidogenesis after vasectomy, immunological consequences after vasectomy, prostatic diseases and vasectomy, late post-vasectomy syndrome, psychological effects after vasectomy, and success rates of vasovasostomy. Besides, the author makes more comments on the results of the clinical trials on new approaches to reversible vas occlusion technique with a new device of Intravasal Thread and to reversible suppression of spermatogenesis with long-acting sex hormones.

• Advances in Traditional Medicine
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• 제6권4호
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• pp.300-305
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• 2006

Pethidine at the dose level of 0.5 mg and 0.75 mg/100 g body weight administered for 20 days to the cycling albino rats caused decrease in the ovarian weight and its protein content. The ovarian folliculogenesis in treated rats is hampered; as a result the follicles which are at the different stages of growth underwent regression. Therefore, the number of healthy follicles is reduced and atretic follicles increased. The elevated levels of ovarian cholesterol and decreased level of glycogen in the pethidine treated rats indicates the inhibition brought in steroidogenesis, which is dependent on pituitary gonadotrophins.

• Advances in Traditional Medicine
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• 제9권4호
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• pp.303-306
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• 2009

The defatted methanol extract of Raphanus sativus Linn. (Cruciferae) seed (MERS) was evaluated for its antisteroidogenic potential in mature female Swiss albino mice. The methanol extract at the doses of 100 and 200 mg/kg body weight significantly elevated the levels of cholesterol and ascorbic acid contents which serve as a precursor for the synthesis of steroid hormones in ovaries. The extract also significantly inhibited glucose-6-phosphate dehydrogenase and ${\Delta}^5-3{\beta}$-hydroxy steroid dehydrogenase, the two key enzymes involved in ovarian steroidogenesis. Hence the extract (MERS) exhibited significant antisteroidogenic activity.

• BMB Reports
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• 제44권5호
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• pp.347-351
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• 2011

The testis is major male gonad responsible for spermatogenesis and steroidogenesis. Much knowledge is still remained to be learned about the control of these events. In this study, we performed a comprehensive bioinformatics analysis on 1,196 mouse testis proteins screened from public protein database. Integrated function and pathway analysis were performed through Database for Annotation, Visualization and Integrated Discovery (DAVID) and ingenuity Pathway Analysis (IPA), and significant features were clustered. Protein membrane organization and gene density on chromosomes were analyzed and discussed. The enriched bioinformatics analysis could provide clues and basis to the development of diagnostic markers and therapeutic targets for infertility and male contraception.