• 생명과학회지
• /
• 제25권11호
• /
• pp.1331-1337
• /
• 2015

S-allylcysteine (SAC)은 숙성된 마늘로부터 유래된 수용성 유기황화합물로서, 여러 유형의 암세포에 대한 항암효과를 갖는 것으로 제시되어왔다. 본 논문은 in vitro 및 in vivo 연구결과에 기초하여 SAC가 세포증식, 세포사멸, 세포주기 및 전이에 미치는 세포신호전달경로와 분자적 메커니즘을 정리하였다. SAC는 Bax와 caspase-3을 포함하는 세포사멸촉진 단백질을 활성화하고 Bcl-2 세포사멸억제 단백질군을 억제하여 미토콘드리아-매개 내인성 경로를 통한 세포사멸을 초래 한다. SAC는 또한 PI3K/Akt/mTOR 및 MAPK/ERK 신호전달경로를 억제하여 NF-κB, cyclins, Cdks, PCNA 및 c-Jun의 발현과 활성을 감소시키고, 세포주기 억제단백질인 p16 및 p21의 발현을 증가시킴으로써 세포주기 억제를 유도하여 세포증식을 억제한다. 뿐만 아니라, SAC는 glutathione-s-transferase (GST)와 같은 항산화효소의 활성을 유도하여 독성물질에 의해 유도된 발암작용을 방지한다. 그리고, SAC는 MAPK/ERK 및 PI3K/Akt/mTOR/NF-κB 신호경로의 억제를 통한 전사억제조절인자 Id-1 및 SLUG의 발현억제를 통하여 초래된 COX-2의 발현감소와 E-cadherin의 발현증가에 의해 신생혈관생성과 MET의 억제를 유도함으로써 암세포의 침투와 전이를 억제한다. 따라서, SAC는 암의 예방과 치료를 위한 하나의 잠재적 화학요법제로 간주될 수 있다.

• Molecules and Cells
• /
• 제27권4호
• /
• pp.443-447
• /
• 2009

This paper reports on the structural rearrangement of satellite DNA type I repeats and heterochromatin during the dedifferentiation and cell cycling of mesophyll protoplasts of cucumber (Cucumis sativus). These repeats were localized in the telomeric heterochromatin of cucumber chromosomes and in the chromocenters of interphase nuclei. The dramatic reduction of heterochromatin involves decondensation of subtelomeric repeats in freshly isolated protoplasts; however, there are not a great many remarkable changes in the expression profile. In spite of that, reformation of the chromocenters, occurring 48 h after protoplast isolation, is accompanied by recondensation of satellite DNA type I; however, only partial reassembly of these repeats was revealed. In this study, FISH and a flow cytometry assay show a correlation between the partial chromocenter and the repeats reassembly, and with the reentry of cultivated protoplasts into the cell cycle and first cell division. After that, divided cells displayed a higher variability in the expression profile than did leaves' mesophyll cells and protoplasts.

• 동의생리병리학회지
• /
• 제24권1호
• /
• pp.55-60
• /
• 2010

Caesalpinia sappan L. (C. sappan) has long been used in traditional medicine as an emmenagogue, hemostatic and anti-inflammatory agent. The present study investigated the effects of water extract of C. sappan in human lymphoma U937 cells. The proliferation of U937 cells was decreased by C. sappan in a dose-dependently manner. Anti-proliferative effect of C. sappan on U937 cells was associated with G2/M phase arrest, which was mediated by regulating the expression of p21 protein. Moreover, phosphorylation of JNK and p38 was increased by C. sappan. Blockade of JNK and p38 was significantly inhibited C. sappan-induced G2/M phase arrest. Taken together, these results suggest that Anti-proliferative effect of C. sappan on U937 is assocated with G2/M phase cell cycle arrest by expression of p21 protein and, JNK and p38 activation.

• BMB Reports
• /
• 제31권4호
• /
• pp.333-338
• /
• 1998

The sphingomyelin cycle and ceramide generation have been recognized as potential growth suppression signals in mammalian cells. Ceramide has been shown to induce differentiation, cell growth arrest, senescence, and apoptosis. Although the intracelluar target for the action of ceramide remains unknown, recent studies have demonstrated the role of cytosolic ceramideactivated protein phosphatase(CAPP). In this study, the cytotoxic effect of C2-ceramide, a synthetic cellpermeable ceramide analog, on HEp-2 cells and the mechanism by which ceramide induces cell death were investigated. The addition of exogenous C2-ceramide resulted in a concentration dependent cell death. Okadaic acid, a potent inhibitor of CAPP, enhanced ceramide-mediated cell death, which suggests that CAPP is not involved in this process. To understand the mechanism of action of ceramide, we studied the relationship between ceramide and c-Myc and pRb which are defined components of cell growth regulation. Western blot analyses revealed that C2-ceramide (10${\mu}M$) induced c-Myc down-regulation, but there were no significant changes in pRb. However, treatment of okadaic acid (10 nM) enhanced c-Myc and pRb down-regulation. Reduction of the amount of c-Myc and pRb occurred during HEp-2 cell death. These results suggest that the cytotoxic effect of ceramide in HEp-2 cells may not be mediated through the action of CAPP and that the downstream target for ceramide is c-Myc and pRb.

• Asian Pacific Journal of Cancer Prevention
• /
• 제14권4호
• /
• pp.2525-2528
• /
• 2013

The Homer protein family, also known as the family of cytoplasmic scaffolding proteins, which include three subtypes (Homer1, Homer2, Homer3). Homer3 can regulate transcription and play a very important role in the differentiation and development for some tissues (e.g. muscle and nervous systems). The current studies showed that Homer3 abnormal expression changes in acute myeloid leukemia (AML). Forced expression of Homer3 in transfected K562 cells inhibited proliferation, influenced the cell cycle profile, affected apoptosis induced by $As_2O_3$ through inhibition of Bcl2 expression, and also promoted cell differentiation induced by 12-O-tetra decanoylphorbol-acetate (TPA). These results showed that Homer3 is a novel gene which plays a certain role in the occurrence and development of AML.

• Journal of Microbiology and Biotechnology
• /
• 제25권10호
• /
• pp.1640-1647
• /
• 2015

We recently reported that the antimicrobial peptide Lumbricusin (NH₂-RNRRWCIDQQA), isolated from the earthworm, increases cell proliferation in neuroblastoma SH-SY5Y cells. Here, we investigated whether Lumbricusin has neurotropic activity in mouse neural stem cells (MNSCs) and a protective effect in a mouse model of Parkinson's disease (PD). In MNSCs isolated from mouse brains, Lumbricusin treatment significantly increased cell proliferation (up to 12%) and reduced the protein expression of p27^Kip1 through proteasomal protein degradation but not transcriptional regulation. Lumbricusin inhibited the 6-OHDA-induced apoptosis of MNSCs, and also showed neuroprotective effects in a mouse PD model, ameliorating the motor impairments seen in the pole, elevated body swing, and rotation tests. These results suggest that the Lumbricusin-induced promotion of neural cell proliferation via p27^Kip1 degradation has a protective effect in an experimental PD model. Thus, the antimicrobial peptide Lumbricusin could possibly be developed as a potential therapeutic agent for the treatment of PD.

• 대한바이러스학회지
• /
• 제30권3호
• /
• pp.161-170
• /
• 2000

Continuous efforts are being made to find effective therapeutic agents against HIV-1, the causative agents of AIDS. In this study, we developed a cell-based assay system employing a trans-complementation for production of recombinant viruses which are capable of undergoing one round of replication in CD4+ T cells. This assay system was tested for ability to screen the agents that act at late stage of HIV-1 life cycle. The effect of a protease inhibitor on the trans-complementation assay was assessed. Recombinant HIV-1 viruses were prepared from a trans-complementation in the presence of various concentrations of protease inhibitor. Inhibition of single round infection of these recombinant viruses by protease inhibitor was observed to be a dose-dependent manner. Inhibitory effects of a protease inhibitor on HIV-1 Gag polyprotein processing by HIV-1 protease was detected at concentrations of the protease inhibitor compatible with inhibition of virus infection, confirming that the corresponding step was involved in the inhibitory mechanism of this compound. Together, these results provide evidence that a cell-based assay system established in this study can be used to screen the agents that target the late stage of HIV-1 life cycle.

• BMB Reports
• /
• 제51권11호
• /
• pp.547-548
• /
• 2018

Phloem network integrates cellular energy status into post-embryonic growth, and development by tight regulation of carbon allocation. Phloem development involves complicated coordination of cell fate determination, cell division, and terminal differentiation into sieve elements (SEs), functional conduit. All of these processes must be tightly coordinated, for optimization of systemic connection between source supplies and sink demands throughout plant life cycle, that has substantial impact on crop productivity. Despite its pivotal role, surprisingly, regulatory mechanisms underlying phloem development have just begun to be explored, and we recently identified a novel translational regulatory network involving RNA G-quadruplex and a zinc-finger protein, JULGI, for phloem development. From this perspective, we further discuss the role of RNA G-quadruplex on post-transcriptional control of phloem regulators, as a potential interface integrating spatial information for asymmetric cell division, and phloem development.

• 한국생명과학회:학술대회논문집
• /
• 한국생명과학회 2005년도 국제학술심포지움 The 44th Annual Meeting of Korean Society for Life Science
• /
• pp.229-229
• /
• 2005

• Journal of Electrochemical Science and Technology
• /
• 제10권2호
• /
• pp.250-255
• /
• 2019

Poly(ethylene oxide) (PEO)-based solid polymer electrolytes (SPEs) show promise for improving the lithium ion battery safety. However, due to oxidation of the PEO group and corrosion of the Al current collector, PEO-based SPEs have not previously been effective for use in $LiCoO_2$ (LCO) cathode materials at room temperature. In this paper, a semi-interpenetrating polymer network (semi-IPN) PEO-based SPE was applied to examine the performance of a LCO/SPE/Li metal cell at different voltage ranges. The results indicate that the SPE can be applied to LCO-based lithium polymer batteries with high electrochemical performance. By using a carbon-coated aluminum current collector, the Al corrosion was mostly suppressed during cycling, resulting in improvement of the cell cycle stability.