• Archives of Pharmacal Research
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• 제27권4호
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• pp.402-406
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• 2004

This research team found in previous studies, that the ginseng saponin metabolite IH901 induces apoptosis in HepG2 cells via a mitochondrial-mediated pathway, which resulted in the activation of caspase-9 and subsequently of caspase-3 and -8. Based on these results, the involvement of the Fas/Fas ligand (FasL) death-receptor pathway, in IH901-induced apoptosis in HepG2 cells, was investigated. Levels of Fas and the Fas ligand (FasL) mRNA or protein were not increased by IH901, rather they were decreased significantly at 18 h post treatment. Soluble FasL (sFasL) was detectable by immunoprecipitation analysis En the medium of HepG2 cells treated with IH901. Increased levels of sFasL were inversely correlated with the levels of FasL. Preincubation of HepG2 cells with antagonistic anti-Fas antibody showed little protective effect, if any, on IH901-induced cell death. At a $30{\mu}M$ (24 and 48 h) and $40{\mu}M$ (24 h) concentration of IH901, the cytotoxic effect of IH901 was less then $50\%$, anti-Fas antibody prevented IH901-induced cell death. However, at a $60{\mu}M$ (24 and 48 h) and $40{\mu}M$ (48 h) concentration of IH901, cell death rates were about $80\%$ or more and most of the chemopreventive and chemotherapeutic effects of IH901 were manifested. Blocking the Fas receptor did not influence IH901-induced cell death. These results indicate that the Fas/FasL system is engaged, but not required for IH901-induced cell death, at pharmacologically significant concentrations.

• Biomolecules & Therapeutics
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• 제7권1호
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• pp.22-28
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• 1999

Induction of apoptosis is considered to be the underlying mechanism that accounts for the efficiency of chemotherapeutic drugs. It has recently been proposed that doxorubicin (DOX) can induce apoptosis in human leukemic cells via the Fas/Fas Ligand (FasL) system. Comparison of Fas and FasL mRNA expression between drug- and anti-Fas antibody(Fas-Ab)- induced apoptosis was analyzed for examining the role of Fas/FasL system in the mediation of drug-induced apoptosis. After HL-60 cells were routinely cultured, MTT assay was performed for cytotoxicity test. Giemsa staining was carried out to monitor the apoptosis morphologically. By semiquantitative RT-PCR analysis, the expression of Fas and FasL at 4, 10, 24 hours was determined after DOX and Fas-Ab treatment. Dose-dependent cytotoxicity was induced by DOX-treatment, while Fas-Ab treatment showed the similar dose-dependent pattern but the cytotoxicity is not reached at LD$_{50}$ at 100 ng/ml concentration of Fas-Ab. In the 10ng/m1 DOX and 10ng/m1 Fas-Ab treated group, typical apoptotic cell morphology was shown such as fragmented nuclei and cell membrane budding in the Giemsa-stained slide. Fas mRNA expression was not changed significantly in the both groups. But, FasL mRNA expression was induced significantly at initial period of apoptosis. In this study, Fas/FasL interaction assumed to be involved in drug-induced apoptosis.s.

• Clinical and Experimental Pediatrics
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• 제49권2호
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• pp.198-202
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• 2006

목 적 : Fas는 세포표면 수용체로 세포사멸 신호를 전도한다. 많은 질환에서 세포표면의 Fas가 Fas ligand(FasL)와 결합하여 세포사멸 과정을 유발하게 된다. 연구자들은 7일된 신생 흰쥐에 저산소성 허혈성 손상을 유발한 후 뇌 해마에서 Fas와 FasL의 발현을 관찰하고자 하였다. 방 법 : 7일된 신생 흰쥐를 오른쪽 총 경동맥 영구 결찰 후 8% 산소에 2시간 노출시켰다. 저산소성 허혈성 손상 후 12, 24, 48시간에 뇌를 적출 냉동 보관하였다. Western blotting 방법과 면역형광염색 방법으로 냉동 보관된 뇌의 경동맥을 결찰한 오른 쪽 해마에서 Fas와 FasL의 발현을 관찰하였다. 결 과 : Fas와 FasL의 발현은 저산소성 허혈성 손상 후 12시간에 경동맥이 결찰된 오른쪽 해마에서 크게 증가하고 이후 감소하는 것을 western blotting 방법에 의해 관찰하였다. Fas와 FasL의 면역형광발현은 오른쪽 해마의 CA1 영역에서 손상 후 12시간과 24시간에 대조군에 비해 증가하였다. Fas의 면역형광 발현은 손상 후 48시간에 감소하였으나 FasL의 면역형광발현은 손상 후 48시간에도 지속되었다. 결 론 : 세포표면에서 Fas와 FasL의 발현과 그들의 결합은 저산소성 허혈성 손상을 받은 미성숙 뇌의 신경세포 손상에 기여할 것으로 추측되었다.

• Clinical and Experimental Reproductive Medicine
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• 제29권3호
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• pp.167-178
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• 2002

Objective : The present study was performed to investigate whether apoptosis occur in human embryos by annexin staining and detect the expression of Fas, Fas-ligand (FasL), Bax, and Bcl-2 in human fragmented embryos derived from IVF-ET by immunofluorescence and Western blot analysis. Materials and Methods: Using annexin staining, immunofluorescence and Western blot analysis on normal and fragmented embryos, we were able to detect apoptotsis and apoptotic gene products in fragmented embryos. Result: Phosphatidylserine (PS) translocation, the marker for apoptosis, were detected frequently in fragmented embryos. Bcl-2 and Bax protein were detected in both fragmented and non-fragmented embryos. When fragmented embryos compared to normal embryos, immunofluorescent intensity of Bcl-2 tended to be lower in fragmented embryos. Bax gene expression increased in the fragmented embryos compared to the normal embryos. This result supports a model in which the molar ratio of Bcl-2 to Bax determines whether apoptosis induced or inhibited in human embryo. Fas was highly expressed in human preimplantation embryos but not FasL. It suggests that embryo may undergo apoptosis by binding with FasL produced by follicular or immune cells. Conclusion: The over expression of Bax and Fas will trigger apoptosis to lead embryo fragmentation and change embryo to be nonviable.

• Radiation Oncology Journal
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• 제21권3호
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• pp.222-226
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• 2003

목적: 변이를 보이는 lpr 마우스와 Fas ligand 변이를 보이는 gld 마우스를 이용하여 in vivo에서 Fas와 Fas ligand의 발현이 전리 방사선에 의해 유도되는 apoptosis에서 어떤 역할을 하는지 조사하고자 하였다. 대상 및 방법: Fas의 변이를 보이는 $C57BL/6J-Fas^{lpr}$ 마우스와 대조군인 C57BL/6J 마우스, Fas ligand 변이를 보이는 $C3H/HeJ-Fas^{gld}$ 마우스와 대조군인 C3H/HeJ 마우스를 대상으로 하였다. 마우스는 8주령 웅성으로서 전신 방사선 조사하여 일정 시간 후 비장을 적출하였다. 조직을 hematoxylin-eosin 염색하여 apoptosis 유도 수준을 비교 분석하였다. 또한 apoptosis 조절 물질인 p53, Bcl-2, Bax, Bcl-X_L,\;Bcl-X_S$에 대하여 Western Western blotting을 시행하고 발현수준을 densitometry로 분석하여 관련된 기전을 연구하였다. 결과: 2.5 Gydh k10 Gy 조사시에 $C57BL/6J-Fas^{lpr}$ 마우스와 $C3H/HeJ-Fas^{gld}$ 마우스에서 대조군 비하여 방사선에 의한 apoptosis가 유의하게 감소되는 것으로 나타났다(p<0.05). C57BL/6J 마우스와, C3H/HeJ 마우스에서 10 Gy 방사선 조사 후 Bax가 8시간 째에 각각 3배, 3.3배의 증가를 보였으나 $C57BL/6J-Fas^{lpr}$ 마우스와, $C3H/HeJ-Fas^{gld}$ 마우스에서는 뚜렷한 발현증가가 관찰되지 않았다. 결과: Fas의 변이가 있는 lpr 마우스와 Fas ligand의 변이가 있는 gld 마우스에서 방사선에 의한 apoptosis가 대조군 보다 현저하게 낮으며 이는 방사선에 의한 Bax의 유도가 미약한 것과 연관된 것으로 나타났다. 방사선에 의한 apoptosis 유도에 Fas의 역할이 매우 중요한 것으로 보인다.

• 한국발생생물학회지:발생과생식
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• 제9권2호
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• pp.115-121
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• 2005

본 연구는 Leydig 세포주와 Sertoli 세포주상에 bisphenol A(BPA)와 diethylstilbestrol(DES)의 영향을 알아보고자 수행하였다. 세포 종류에 따른 BPA의 영향을 알아보기 위해, BPA의 농도별로 두 세포주에 처리하여 세포생존율을 비교하였다. Sertoli 세포주가 Leydig 세포주에 비해서 저농도의 BPA에서 생존율이 유의하게 감소되는 것을 확인할 수 있어, Sertoli 세포가 Leydig 세포주에 비해 BPA에 더욱 민감한 것을 알 수 있었다. 또한 BPA나 DES를 처리했을 때 세포 내 분화 및 사멸 신호 전달에 관여하는 phospholipase D(PLD)의 활성이 현저하게 저하되는 것을 확인하였다. 역전사효소 연쇄 반응을 이용하여 세포막상의 세포자연사 신호전달자인 fas 와 fas ligand의 mRNA 발현을 확인해 본 결과, BPA의 처리에 의해 fas ligand의 발현이 다른 실험군에 비해 유의하게 증가하는 것을 확인할 수 있었다. 이상의 결과들을 정리해 볼 때, 내분비계 교란물질인 BPA는 Sertoli 세포 내 fas/fasL 신호전달계를 자극하여 PLD 활성을 저하시킴으로서, Sertoli 세포 내 세포자연사를 유발시키는 것으로 사료된다.

• Biomolecules & Therapeutics
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• 제20권2호
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• pp.177-182
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• 2012

Tetrazolium violet is a tetrazolium salt and has been proposed as an antitumor agent. In this study, we reported for the first time that tetrazolium violet not only inhibited human lung cancer A549 cell proliferation but also induced apoptosis and blocked cell cycle progression in the G1 phase. The results showed that tetrazolium violet significantly decreased the viability of A549 cells at $5-15{\mu}M$. Tetrazolium violet -induced apoptosis in A549 cells was confirmed by H33258 staining assay. In A549, tetrazolium violet blocked the progression of the cell cycle at G1 phase by inducing p53 expression and further up-regulating p21/WAF1 expression. In addition, an enhancement in Fas/APO-1 and its two forms of ligands, membrane-bound Fas ligand (mFasL) and soluble Fas ligand (sFasL), as well as caspase, were responsible for the apoptotic effect induced by tetrazolium violet. The conclusion of this study is that tetrazolium violet induced p53 expression which caused cell cycle arrest and apoptosis. These findings suggest that tetrazolium violet has strong potential for development as an agent for treatment lung cancer.

• 한국수정란이식학회지
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• 제13권2호
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• pp.179-190
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• 1998

Prolactin (PRL) surge in cycling rats at proestrous afternoon has previously been reported as an inducer of apoptotic cell death of luteal cells. This death-inducing action of PRL seeins unusual, because PRL can he categorized as a cell-survival factor, if other known physiological functions of PRL are taken into account. In this study, the apoptotic action of PRL was assessed in cultured cells prepared from rat luteal tissue and underlying molecular /cellular mechanism of PRL-induced luteolysis was analyzed. The latest crop of corpora lutea (CLs) were enucleated from rat ovaries at 18:00 h on the proestrous day before the next ovulation. Donor rats were pretreated with CB154, a dopamine agonist, in order to he exempted from the endogenous PRL surge. The harvested GLs were dispersed and cultured with or without PRL (2$\mu$g /ml) for 24 or 48 h. An addition of PRL to the culture medium changed the parameters indicative of cell death via apoptosis: a decrease in cell viability (MTT) and an increase in chromatin condensation. Most of the DNA breakdown in nuclei induced by PRL occurred in steroidogenic cells which were identified by 3$\beta$-HSD activity staining, and the number of 3$\beta$-HSD-positivecells were significantly decreased. Interestingly, most of the cells with an apoptotic nucleus adhered to one or more intact and seemingly non-steroidogenic cells. Because the expression of Fas has heen shown to be abundant in murine ovary, and Fas is known to have an exact physiological role in occurrence of apoptotic cell death, the membrane form-Fas ligand (rnFasL) was quantified in the cell lysate. An addition of PRL increased expression of mFasL. Moreover, an addition of concanavalin A (ConA), a T-cell specific activator, in place of PRL, enhanced the apoptotic parameters. Cumulatively, the apoptotic PRL action was addressed to cells unknown than steroidogenic lute~ cells. The most prohable candidate for the direct target cells is Tcells in the luteal tissue that can express mFasL in response to PRL.

• 대한수의학회지
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• 제43권3호
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• pp.485-492
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• 2003

The pathological mechanism of impaired spermatogenesis after vasectomy has not been completely investigated. In this study, we examined pathological changes of the testis and the Fas-Fas ligand (FasL) mediated signaling pathway in apoptotic germ cell death after vasectomy in rats. Ten-weeks old Sprague-Dawley rats were underwent bilateral vasectomy and sacrificed after 1 day, 2 days, 3 days, 5 days, 1 week, 2 weeks, and 4 weeks of surgery and the testes were removed. Histopathological evaluation of spermatogenesis was performed by hematoxylin-eosin and periodic acid-Schiff-hematoxylin staining. To elucidate the pathophysiology of seminiferous tubule damage, terminal dUTP nick end labeling staining, electrophoresis assay of DNA fragmentation, and Western blotting analysis for Fas-FasL were performed. Relative weights of testes were decreased from 5 days after vasectomy. Germ cell degeneration were first found in the spermatogonia and spermatocytes at stages I-VI, and XII-XIV seminiferous tubules. Mean incidence of apoptotic germ cells after vasectomy progressively increased to peak in 5 days, and then gradually decreased to the control levels in 2 weeks after vasectomy. The expression of Fas-FasL reached maximum level at 5 days after vasectomy and then declined. In conclusion, impaired spermatogenesis after vasectomy associated with an increase in germ cell apoptasis, which is partly mediated by the activation of Fas-FasL.

• Clinical and Experimental Reproductive Medicine
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• 제29권3호
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• pp.195-200
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• 2002

Objective : To investigate the expression of apoptosis related proteins and apoptotic cells on the human ovarian follicles. Materials and Methods: Thirty five Formalin-fixed paraffin-embedded human ovarian tissue blocks were selected from the surgical pathology files of the department of pathology, College of Medicine, Yonsei University, for the period from 1996 to 1998. All specimen were from premenopausal women aged from $32{\sim}45$. Ovarian tissues were collected from the patients performing hysterectomy for benign uterine diseases. Immunohistochemical staining was performed for the detection of DNA fragmented cell, Bcl-2, Bax, Fas and Fas-ligand. Results: Bcl-2 and bax were not expressed on the surrounding cells and oocyte of the primary, primordial and preantral follicles. Fas and Fas-ligand (Fas-L) were not expressed on the surrounding cells on the primordial and primary follicles. But expressed on the surrounding granulosa cells and oocyte in the primordial and primary follicles. In the healthy follicles, Bcl-2 was expressed on the granulosa cells, however, Bax was not expressed. DNA fragmented cells were expressed on the inner granulosa cell layer of atretic follicles. Conclusion: Fas, Fas-ligand, and Bax may be responsible for the follicular atresia and Bcl-2 may be involved in the follicular survival in the human ovary.