• International Journal of Oral Biology
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• v.44 no.3
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• pp.115-123
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• 2019

Among the environmental chemicals that may be able to disrupt the endocrine systems of animals and humans are polychlorinated biphenyls (PCBs), a chemical class of considerable concern. PCB consists of two six-carbon rings linked by a single carbon bond, and theoretically, 209 congeners can form, depending on the number of chlorines and their location on the biphenyl rings. Furthermore, 3,3',4,4',5-pentachlorobiphenyl (PCB126) exposure also increases nitric oxide production and nuclear factor kappa-light-chain-enhancer of activated B cells binding activity in chondrocytes, thus contributing as an initiator of chondrocyte apoptosis and resulting in thymic atrophy and immunosuppression. This study identified whether cardiac and immune abnormalities from PCB126 were caused by the Kv1.3 and Kv1.5 channels. PCB126 did not affect either the steady-state current or peak current of the Kv1.3 and Kv1.5 channels. However, PCB126 right-shifted the steady-state activation curves of human Kv1.3 channels. These results suggest that PCBs can affect the heart in a way that does not block voltage-dependent potassium channels including Kv1.3 and Kv1.5 directly.

• Proceedings of the Ginseng society Conference
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• 1998.06a
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• pp.300-311
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• 1998

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD), one of the most notorious toxic environmental pollutants, induces various toxic effects in many organs including testes and is regarded as an endocrine disruptor. Korean ginseng, on the other hand, has been well known for its preventive effects on lox- ins, diabetes melltus and hyperlipidemia. We investigated, histopathologically, the effect of Korean Red ginseng water extract (KR-WE) on guinea pig testes damaged by TCDD. Ninety guinea pigs were divided into 6 groups: normal control (NC) group received vehicle and saline; TCDD,1191kg b.w., was administered intraperitoneally to the single dose TCDD-treated (77) group; 100 mghg b.w.16 and 200mg1kg b.w./d KR-WE were injected intraperitoneally to the preventive groups (PIOO and P2OO, respectively) for 28 days from 1 week before TCDD injection, and to the therapeutic groups (CIOO and C2OO, respectively) for 14 days since 1 week after TCDD administration. Increment of body weight was retarded to a larger extent by TCDD. Moreover, body weight of the 77 group decreased significantly 7 days after TCDD exposure, while that of preventive groups kept increasing. Decrease in body weight was not observed in KR-WE-treated groups. Weight decrease in testes caused by TCDD was remarkably protected by KR-WE. Testicles in 77 group displayed decreased tubular size and maturation arrest at the primary or secondary spermatocyte stage. On the other hand, maturation arrest in germ cells by TCDD was improved in KR-WE treated groups. Almost complete protection of the testes was observed in PIOO and P2OO groups. In addition, the therapeutic effect was noticed in C 100 and C2OO groups. These results provided strong evidence that Korean Red ginseng might be a useful agent for the prevention and treatment of testicular damage induced by environmental pollutants.

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2002.11a
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• pp.112-112
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• 2002

Under normal conditions, women produce a single dominant follicle that participates in a single ovuation each menstrual cycle. But Polycystic ovary syndrome(PCOS) conditions, folliculogenesis does not proceed normally. This condition leads to the accumlation of large numbers of small graffian follicles in which the theca interstitial cells (TIC) produce abnormally large amounts of androgen. PCOS is probably the most common endocrine disorder, affecting women of reprodutive age with 5-10% prevalence estimate. Chronic anovulation, hyperandrogenism, hirsutism, obesity, infertility and polycystic ovaries are clinical hallmarks of women with PCOS. Its etiology remains unknown. To investigate the gene expression pattern of ovary in PCO-induced rat, we used cDNA expression analysis. Total RNA was extracted from the ovary of PCO-induced rat and reverse-transcribed in the presence of［$\alpha$$^{32}$P］-dATP Which were hybridized to Atlas$^{TM}$ Rat Toxicology 1.2 array (Clontech) representing approximately 1176 rat genes. We compared gene expression between ovary of pco-induced immature female rats and control. Differential gene expression profiles were revealed (LIFR-alpha, ADRA1A, Heat shock 90-kDa protein A, PDGFRA). Reverse transcription-polymerase chain reaction(RT-PCR) was used to validate the relative expression pattern obtained by the cDNA array. The precise relationship between the altered expression of genes and PCO is a matter of further investigation. This study was supported by Korea Science and Engineering Foundation(KOSEF)

• Journal of Ginseng Research
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• v.47 no.3
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• pp.385-389
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• 2023

Background: Ginseng has been used as a traditional medicine for treatment of many diseases and for general health maintenance. Previously, we showed that ginseng did not demonstrate estrogenic property in ovariectomized mouse model. However, it is still possible that disruption of steroidogenesis leading to indirect hormonal activity. Methods: The hormonal activities were examined in compliance with OECD guidelines for detecting endocrine disrupting chemicals: test guideline (TG) No. 456 (an in vitro assay method for detecting steroidogenesis property) and TG No. 440 (an in vivo short-term screening method for chemicals with uterotrophic property). Results: Korean Red Ginseng (KRG) and ginsenosides Rb1, Rg1, and Rg3 did not interfere with estrogen and testosterone hormone synthesis as examined in H295 cells according to TG 456. KRG treatment to ovariectomized mice did not show a significant change in uterine weight. In addition, serum estrogen and testosterone levels were not change by KRG intake. Conclusion: These results clearly demonstrate that there is no steroidogenic activity associated with KRG and no disruption of the hypothalamic-pituitary-gonadal axis by KRG. Additional tests will be performed in pursuit of cellular molecular targets of ginseng to manifest mode of action.

• Development and Reproduction
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• v.27 no.4
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• pp.195-203
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• 2023

Exposure to environmental chemicals, including endocrine-disrupting chemicals, during the gestational period can have profound adverse effects on several organs in offspring. Bisphenol A (BPA) can infiltrate the human body through food and drinks, and its metabolites can cross both the placental and the blood-brain barriers. In this study, we investigate the effect of gestational exposure to BPA on epigenetic, biochemical, and histological modifications in the uterine tissues of F1 adult offspring rats. Pregnant rats were exposed to BPA from gestational day 8-15, and changes in global DNA methylation in uterine tissues obtained from adult offspring born to the exposed mothers were analyzed. Global DNA methylation analysis revealed that gestational exposure to BPA resulted in DNA hypomethylation in the uterus. Progesterone receptor (PR) protein expression in uterine tissues was monitored using western blot analysis, which revealed that the PR protein content was considerably higher in all BPA-exposed groups than in the control. Immunohistochemical examination for the PR revealed that intense PR-positive cells were more frequently observed in the BPA-exposed group than in the control group. To date, the evidence that the upregulation of PRs observed in the present study was caused by the non-methylation of specific PR promoter regions is lacking. Conclusively, these results indicate that exposure to BPA during gestation induces epigenetic alterations in the uteri of adult female offspring. We speculate that the global DNA hypomethylation and upregulation of the PR observed simultaneously in this study might be associated with the uterus.

• BMB Reports
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• v.57 no.3
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• pp.149-154
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• 2024

The stomach has emerged as a crucial endocrine organ in the regulation of feeding since the discovery of ghrelin. Gut-derived hormones, such as ghrelin and cholecystokinin, can act through the vagus nerve. We previously reported the satiety effect of hypothalamic clusterin, but the impact of peripheral clusterin remains unknown. In this study, we administered clusterin intraperitoneally to mice and observed its ability to suppress fasting-driven food intake. Interestingly, we found its synergism with cholecystokinin and antagonism with ghrelin. These effects were accompanied by increased c-fos immunoreactivity in nucleus tractus solitarius, area postrema, and hypothalamic paraventricular nucleus. Notably, truncal vagotomy abolished this response. The stomach expressed clusterin at high levels among the organs, and gastric clusterin was detected in specific enteroendocrine cells and the submucosal plexus. Gastric clusterin expression decreased after fasting but recovered after 2 hours of refeeding. Furthermore, we confirmed that stomachspecific overexpression of clusterin reduced food intake after overnight fasting. These results suggest that gastric clusterin may function as a gut-derived peptide involved in the regulation of feeding through the gut-brain axis.

• Applied Microscopy
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• v.37 no.4
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• pp.249-258
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• 2007

The Pancreatic islet are the clusters of endocrine cells scattered through out the exocrine pancreas. Transplantation of a sufficient pancreatic islets can normalize blood glucose level so that may prevent devastating complications of type I diabetes(IDDM) and other side effects of the IDDM. Recently, there are several approaches to transplant sufficient pancreatic islet, and it was comprised in increase or regeneration of the endogenous $\beta$-cell mass from donor's pancreas, but relatively few studies have been devoted to the morphological characters of the isolated and 3 day cultured pancreatic islets. We investigated morphological pattern of intracellular structure of isolated and 3 day cultured pancreatic islets. The morphological characters of the pancreatic islets were observed by scanning electron microscope and transmission electron microscope, and insulin distribution of the each islets were observed by transmission electron microscope, and were labeled with insulin antibody. Intracellular structures including nuclei, mitochondria, RER, Golgi complex and many secretory granules were normally appeared in the isolated pancreatic islets which was extracted immediately dornor's pancreas, however, There is a significant morphological changes between the 3 day cultured pancreatic islets and isolated islets. 3 day cultured pancreatic islet's $\beta$-cells had normal nuclei but increased cytoplasm mass and RER and developed Golgi complex. Insulin secretory granules were decreased in numbers rather than isolated pancreatic islet. In this study, the pattern of intracellular structure variation was examined during pancreatic islet culture. Most distinct features are variation of the insulin secretory granules, and developed RER, and dilated golgi complex. Therefore, we suggested that the various change of the morphological characters on cultured pancreatic islets were responsible for the function(biosynthesis and secretion of insulin) and growth. These results were also cultured islets have greater ability to recover and maintain normoglycemia than isolated islet transplantation.

• Journal of Yeungnam Medical Science
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• v.8 no.2
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• pp.76-83
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• 1991

A total of 53 gastric adenomas from endoscopically biopsied gastric mucosa were examined histopathologically. The average age at the time of endoscopic biopsy was 59 years, and gastric adenomas were found to be more frequent in the aged, particularly above the age of 50. The majority of adenomas occurred at the antrum. Concerning the shape of the adenomas, Yamada type II was more frequent(55%). All adenomas were accompanied by varying degree of intestinal metaplasia, and this findings suggest that gastric adenoma develops from intestinal metaplasia. In adenomas with severe atypia(grade III), endocrine cells(argyrophil and argentaffin cells)were markedly decreased or absent. Gastric adenocarcinomas coexistent with adenoma were seen in 5(9.4%) out of 53 cases, and were more frequent in male than female patients(sex ratio, 4 : 1) and the average age was 61.4 years. It is suggested that there is a necessity of thorough follow-up study for definitive correlation between gastric adenoma and adenocarcinoma.

• Molecular & Cellular Toxicology
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• v.4 no.4
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• pp.348-354
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• 2008

Bisphenol A (BPA), an environmental endocrine disrupter, enters the human body continuously in food and drink. Young children are likely to be more vulnerable than adults to chemical exposure due to the immaturities of their organ systems, rapid physical development, and higher ventilation, metabolic rates, and activity levels. The direct effect of BPA on peripheral tissue might also be of importance to the development of insulin resistance. However, the influence that BPA has on insulin signaling molecules in skeletal muscle has not been previously investigated. In this study, we examined the effect of BPA on fasting blood glucose (FBG) in post-weaned Wistar rats and on insulin signaling proteins in C2C12 skeletal muscle cells. Subsequently, we investigated the effects of BPA on insulin-mediated Akt phosphorylation in C2C12 myotubes. In rats, BPA treatment (0.1-1,000 ng/mL for 24 hours) resulted in the increase of FBG and plasma insulin levels, and reduced insulin-mediated Akt phosphorylation. Furthermore, the mRNA expression of insulin receptor (IR) was decreased after 24 hours of BPA treatment in C2C12 cells in a dose-dependent manner, whereas the mRNA levels of other insulin signaling proteins, including insulin receptor substrate-1 (IRS-1) and 5'-AMP-dependent protein kinase (AMPK), were unaffected. Treatment with BPA increased GLUT4 expression and protein tyrosine phosphatase 1B (PTP1B) activity in C2C12 myotubes, but not in protein levels. We conclude that exposure to BPA can induce insulin resistance by decreasing IR gene expression, which is followed by a decrease in insulin- mediated Akt activation and increased PTP1B activity.

• Journal of Life Science
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• v.18 no.4
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• pp.537-541
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• 2008

White adipose tissue is now recognized as an important endocrine organ which secretes various signal factors and proteins termed 'adipokine'. Haptoglobin (Hp), which has been known as an acute phase protein, belongs to the adipokine. However, the function of Hp in adipose tissue remains unclear. To verify the role of Hp in preadipocytes, in this study, 3T3-L1 preadipocyte cells were stably transfected with human Hp gene and Hp-overexpressing cells were made. The Hp had no effect on cell growth of preadipocytes. By RT-PCR and Western blot analysis, the Hp inhibited gene expression of IL-6 and COX-2 and enhanced HO-1 synthesis in preadipocytes. Moreover, invasion assay showed the Hp suppressed migration of monocytes to preadipocytes. These findings suggest that the Hp may inhibit an inflammatory reaction in adipose tissue by regulating the expressions of pro-inflammatory and anti-inflammatory mediators, and by repressing monocytes/macrophages infiltration.