• Clinical and Experimental Reproductive Medicine
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• 제46권3호
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• pp.99-106
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• 2019

Bisphenol A (BPA) is an endocrine-disrupting chemical that is capable of interfering with the normal function of the endocrine system in the body. Exposure to this chemical from BPA-containing materials and the environment is associated with deleterious health effects, including male reproductive abnormalities. A search of the literature demonstrated that BPA, as a toxicant, directly affects the cellular oxidative stress response machinery. Because of its hormone-like properties, it can also bind with specific receptors in target cells. Therefore, the tissue-specific effects of BPA mostly depend on its endocrine-disrupting capabilities and the expression of those particular receptors in target cells. Although studies have shown the possible mechanisms of BPA action in various cell types, a clear consensus has yet to be established. In this review, we summarize the mechanisms of BPA action in spermatozoa by compiling existing information in the literature.

• 한국동물번식학회:학술대회논문집
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• 한국동물번식학회 2003년도 학술발표대회 발표논문초록집
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• pp.51-51
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• 2003

Oct-4 is a maternally expressed octamer-binding protein encoded by the murine Oct-4 gene. It is present in unfertilized oocytes, but also in the inner cell mass and in primordial germ cells. In addition, Oct-4 is the first transcrition factor described that is specific for the blastocysts stage bovine embryos. The spatial and temporal expression patterns were further determined using Immunohistochemistry. With this technique Oct-4 protein expression is detected in the oocyte, in the blastocyst. After pregnancy Oct-4 expression is restricted ovary and placental tissue. Therefore Oct-4 is a transcription factor that is specifically expressed in cells participating in the pregnancy of Korean native cattle. These result suggest that Oct-4 localization and expression may contribute to the defects in the developmental normal seen in Korean native cattle.

• 한국임상수의학회지
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• 제17권1호
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• pp.76-82
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• 2000

This study was undertaken to find out the effect of persimmon leaves on histopathological changes of cadmium toxicity in mice. Seventy two BALB/c mice of male were divided into a control group(A) and five experimental groups (B, C, D, E, F) : group A received tap water and basal diet, group B received tap water and diet supplemented with 3% persimmon leaves alone, group C received basal diet and 300 ppm cadmium, group D, E and F received basal diet supplemented with 1, 3% and 7% persimmon leaves and 300 ppm cadmium respectively. Cadmium dissolved in tap water was used, and the persimmon leaves were mixed with feed. All mice were dissected on the 84th day. Pathological changes in liver, kidney, cortical osseous tissue of femoral shaft, bone trabecular of femur, and epiphyseal cartilage plate of femur were observed. Group B showed no significant changes as the control group. But group C showed the unclearness of specific cells in liver, the loss of architecture and necrosis of hepatocyte, degeneration and necrosis of renal convoluted tubules, desquamation and vacuolization of the greater part of the renal tubular epithelium, marked thinning of the cortical osseous tissue in femoral shaft, reduction of cancellous bone volume and decreaswe of trabecular number, and marked thinning of epiphyseal cartilage plate in femur. On the other hand, persimmon leaves-treated group showed a little convalescent changes an maintained their normal architectures in liver, kidney, cortical osseous tissue of femoral shaft, bone trabecular of femur, and epiphyseal cartilage plate of femur.

• Biomolecules & Therapeutics
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• 제8권2호
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• pp.119-124
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• 2000

We hypothesized that the extent of hypoxic injury would be involved in reduction of oxygen delivery to the tissue. Livers isolated from 18 hr-fasted rats were subjected to $N_2$-induced hypoxia or low flow hypoxia. Livers were perfused with nitrogen/carbon dioxide gas for 45min or perfused with normoxic Krebs-Henseleit bicarbonate buffer (KHBB) at low flow rates around 1 ml/g liver/min far 45min, which caused cells to become hypoxic because of insufficient delivery of oxygen. When normal flow rates(4 ml/g liver/min) of KHBB (pH 7.4, 37$^{\circ}C$, oxygen/carbon dioxide gas) were restored for 30min reoxygenation injury occurred. Lactate dehydrogenase release gradually increased in $N_2$-induced hypoxia, whereas it rapidly increased in low flow hypoxia. Total glutathione in liver tissue was not changed but oxidized glutathione markedly increased after hypoxia and reoxygenation, expecially in $N_2$-induced hypoxia. Similarly, lipid peroxidation in liver tissue significantly increased after hypoxia and reoxygenation in low flow hypoxia. Hepatic drug metabolizing functions (phase I, II) were suppressed during hypoxia, especially in $N_2$-induced hypoxia but improved by reoxygenation in both models. Our findings suggest that hypoxia results in abnormalities in drug metabolizing function caused by oxidative stress and that this injury is dependent on hypoxic conditions.

• Journal of Korean Neurosurgical Society
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• 제48권1호
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• pp.20-30
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• 2010

Objective : We determined whether the expression of GRIM-19 is correlated with pathologic types and malignant grades in gliomas, and determined the function of GRIM-19 in human gliomas. Methods : Tumor tissues were isolated and frozen at $-80^{\circ}C$ just after surgery. The tissues consisted of normal brain tissue (4), astrocytomas (2), anaplastic astrocytomas (2), oligodendrogliomas (13), anaplastic oligodendrogliomas (11), and glioblastomas (16). To profile tumor-related genes, we applied RNA differential display using a $Genefishing^{TM}$ DEG kit, and validated the tumor-related genes by reverse transcription polymerase chain reaction (RT-PCR). A human glioblastoma cell line (U343MG-A) was used for the GRIM-19 functional studies. The morphologic and cytoskeletal changes were examined via light and confocal microscopy. The migratory and invasive abilities were investigated by the simple scratch technique and Matrigel assay. The antiproliferative activity was determined by thiazolyl blue Tetrazolium bromide (MTT) assay and FACS analysis. Results : Based on RT-PCR analysis, the expression of GRIM-19 was higher in astrocytic tumors than oligodendroglial tumors. The expression of GRIM-19 was higher in high-grade tumors than low-grade tumors or normal brain tissue; glioblastomas showed the highest expression. After transfection of GRIM-19 into U343MG-A, the morphology of the sense-transfection cells became larger and more spindly. The antisensetransfection cells became smaller and rounder compared with wild type U343MG-A. The MTT assay showed that the sense-transfection cells were more sensitive to the combination of interferon-$\beta$ and retinoic acid than U343MG-A cells or antisense-transfection cells; the antiproliferative activity was related to apoptosis. Conclusion : GRIM-19 may be one of the gene profiles which regulate cell death via apoptosis in human gliomas.

• 한국가축번식학회지
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• 제19권4호
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• pp.307-322
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• 1996

The corpus luteum (CL) is formed by the action of a surge of luteinizing hormone (LH) on the pre-ovulatory follicle. Luteal cells derived from granulosa and theca interna cells continue to secrete progesterone for about two weeks. LH in domestic animals is essential for the normal secretion of progesterone at all stages of the luteal phase. For this process in the rodents, 20$\alpha$-hydroxysteroid dehydrogenase (20$\alpha$-HSD) is indispensable. 20$\alpha$-HSD is an enzyme to be a biologically inactive steroid. This enzyme plays a critical role in the regulation of the rat luteal function and reported to be present in steroid-producing tissues such as the testis and adrenal gland. We have purified 20$\alpha$-HSD and found two distinct 20$\alpha$-HSD molecules (HSD-1 and HSD-2). Their molecular weights are both estimated to be 33kd.The amino acid compositions of HSD-1 and HSD-2 are mostly similar, but there is a slight difference in the content of lysine. We demonstrated that 1) CL of previous generations contribute more to whole ovarian 20$\alpha$-HSD activity, 2) newly formed corpora lutea contain only 20$\alpha$-HSD-1 activity, and 3) old CL express activities of each HSD isozyme as shown in the luteal tissue of cycling rats on the day of diestrus where only degenerating old CL exist. The increase in 20$\alpha$-HSD activity identified seems to be related to the increase in the numbers of 20$\alpha$-HSD-positive cells. Interestingly, 20$\alpha$-HSD-1 activities were strongly found in the follicle fluids and theca interna cells by immunohistochemical study. Thus, the activity of 20$\alpha$-HSD may be related to a survival mechanism of those luteal cells and follicles remaining in the ovaries. Luteal cells arise from two sources. The small luteal cells are all of theca cell origin, while the large luteal cells are mainly of granulosa cell origin. CL of Korean Native Cattle, as those of other animal species, contains two morphologycally and functionally distinct luteal cell populations, such as small and large luteal cells as well as nonluteal cells. In all reproductive states except in the late luteal phase, the bovine CL also contained more small luteal cells than large luteal cells. Luteal tissue secretes a variety of growth factors (proteins) and the pattern of secretion changes during all stages of the luteal phase. These growth factors could be important in regulating the function of the bovine corpus luteum and may act in a potential endocrine autocrine and paracrine mechanisms. Therefore, further work has to be done to elucidate the role of growth factors in the ovary, especially in the corpus luterum. Interest should be focussed on interaction of these growth factors in the regulation of luteal cell and the localization of cytokine synthesis in differnet luteal cells.

• Imaging Science in Dentistry
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• 제30권3호
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• pp.159-168
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• 2000

Purpose: To elucidate the effects of the irradiation and calcium-deficient diet on expression of interleukin (IL)-1 during tooth formation of rat molar. Materials and Methods: The pregnant three-week-old Spague-Dawley rats were used for the study. The control group was non-irradiation/normal diet group, and the experimental groups were irradiation/normal diet group and irradiation/calcium-deficient diet group. The abdomen of the rats on the 9th day of pregnancy were irradiated with single dose of 350 cGy, The rat pups were sacrificed on the 14th day after delivery and the maxillae tooth germs were taken. The specimen were prepared to make sections for light microscopy, and some of tissue sections were stained immunohistochemically with anti-IL-l antibody. Results: In the irradiation/normal diet group, dental follicle showed fewer blood vessels, mononuclear cells, and fusions of mononuclear cells than in non-irradiation/normal diet group. Alveolar bone showed a few osteoblasts and osteoclasts. Periodontal ligament showed collagen fibers and fibroblasts with irregularity. Weak immunoreactivity for IL-l was shown in dental follicle, alveolar bone, and periodontal ligament. In the irradiation/calcium-deficient diet group, dental follicle showed sparse cellularity. Alveolar bone showed diminished number of osteoblasts. Periodontal ligament showed irregular collagen fibers and atrophy of cementoblasts and fibroblasts. No immunoreactivity for IL-1 was shown in dental follicle, alveolar bone, and periodontal ligament. Conclusion: Irradiation and calcium-deficient diet seems to cause disturbance of the expression of interleukin-l during tooth formation of rat molar.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제26권2호
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• pp.132-136
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• 2000

The cell surface glycoprotein CD44 is a kind of adhesion molecule, which binds hyaluronic acid, type I collagen and fibronectin. Although there have been numerous reports on the expression and the function of CD44 in lymphocytes and macrophages, very little is known about its distribution and definite role in epithelial tissue, especially in oral epithelial one. The present study was performed to investigate the distribution and expression of the CD44 in human gingiva and squamous cell carcinoma(SCC) arising in human gingiva. And the authors compared CD44 expression with histopathologic grade of SCC. The results were as follows: 1. The CD44 was strongly expressed in granular, spinous and basal layers of normal marginal and attached gingiva, in spinous and basal layers of normal sulcular gingiva, and in all epithelial layers of normal junctional gingiva. 2. In SCC of gingiva, the CD44 was expressed in all but one case. In most of the cases the CD44 was expressed at cell membrane and the degree of expression was relatively strong. 3. In low-grade SCC of gingiva, the CD44 was strongly expressed, especially at the basal and spinous layers of abundantly keratinized cancer nests. In high-grade SCC of gingiva, the CD44 expression tended to be weak but was strong at cells showing individual keratinization. This study suggest that the CD44 expression of normal and cancerous gingival epithelium is associated with the degree of proliferation and differentiation of epithelial cells.

• 생명과학회지
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• 제22권10호
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• pp.1415-1419
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• 2012

Thymosin ${\beta}4$ 는 대장암에서 암 줄기세포 마커인 CD133을 지닌 세포에서 지니지 않은 세포에 비해 강하게 발현된다고 보고되어 있다. 본 연구에서는 thymosin ${\beta}4$와 줄기세포 마커인 CD133의 상관관계를 정상 위 조직에서 관찰하였다. Thymosin ${\beta}4$와 CD133의 발현 양상은 tissue microarray 조직상에서 면역화학적 방법으로 관찰하였으며 thymosin ${\beta}4$와 CD133의 존재 위치는 면역형광 염색법 및 confocal microscope를 사용하여 조사하였다. Thymosin ${\beta}4$와 CD133은 동일한 양상으로 발현되었으며 모두 위의 선조직에서 강하게 발현되었다. 면역 형광 염색법으로 두가지 단백질을 동시에 염색한 결과 두 단백질이 동일한 위치에서 함께 존재하는 것으로 규명되었다. 이러한 결과는 thymosin ${\beta}4$와 CD133은 정상위의 선조직에서 발현되며 두 단백질의 발현 양상 및 위치가 동일하여 서로 긴밀한 상호작용을 할 가능성을 제시하고 있다.

• BMB Reports
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• 제50권8호
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• pp.411-416
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• 2017

The endoplasmic reticulum (ER) membrane protein complex subunit 6 (EMC6) is a novel human autophagy-related molecule. Here, using tissue microarray and immunohistochemistry, we report that EMC6 protein is lost or reduced in glandular cells of patients with gastric adenocarcinoma, compared to normal stomach mucosa. Overexpression of EMC6 in gastric cancer cells inhibited cell growth, migration, invasion, and induced apoptosis and cell cycle arrest at S-phase. Further investigation suggested that EMC6 overexpression in BGC823 human adenocarcinoma gastric cancer cells reduced tumorigenicity in a xenograft model, demonstrating that EMC6 has the characteristics of a tumor suppressor. This is the first study to show that EMC6 induces cell death in gastric cancer cells. The molecular mechanism of how EMC6 functions as a tumor suppressor needs to be further explored.