• 한국독성학회:학술대회논문집
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• 한국독성학회 2002년도 국제심포지움
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• pp.88.2-98
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• 2002

A wide arry of naturally occurring substances particularly those present in dietary and medicinal plants, have been reported to possess substantial cancer chemopreventive properties. Certain phytochemicals retain strong antioxidative and anti-inflammatory properties which appear to contribute to their chemopreventive or chemoprotective activities. Inducible cyclooxygenase(COX-2) and nitric oxide synthase (iNOS) are important enzymes that mediate inflammatory processes. There is some evidence that expression of both COX-2 and iNOS is co-regulated by the eukaryotic transcription factor NF-$textsc{k}$B. Increased expression of COX-2 and/or iNOS has been associated with pathophysiology of certain types of human cancers as well as inflammatory diseases. Since inflammation is closely linked to tumor promotion, substances with potent anti-inflammatory activies are anticipated to exert chemopreventive effects on carcinogenesis, particularly in the promotion stage. An example is curcumin, a yellow pigment of turmeric (Curcuma longa L., Zingiberaceae), that strongly occurring diaryl heptanoids structurally related to curcumin have substantial anti-tumor promotional activities in two-stage mouse skin carcinogenesis. Thus, yakuchinone A [1-(4'-hydroxy-3'-methoxyphenyl)-7-phenyl-3heptanone] and yakuchinone B [1-(4'-hydroxy-3'methoxyphenyl)-7-phenylhept-1-en-3-one] present in Alpinia oxyphylla Miquel (Zingiberacease) attenuate phorbol ester-induced inflammation and papilloma formation in female ICR mice. These diarylheptanoids also suppressed phorbol ester-induced activation of epdermal ornithine decarboxylase and its mRNA expression when applied onto shaven backs of mice. Yakuchinone A and B as well as curcumin inhibited phorbol ester-induced expression of COX-2 and iNOS and their mRNA in mouse skin via inactivation of NF-$textsc{k}$B. Capsaicin, a major pungent ingredient of red pepper also attenuated phorbol ester-induced NF-$textsc{k}$B activation. Similar suppression of COX-2 and iNOS and down-regulation of NF-$textsc{k}$B activation for its DNA binding were observed with the ginsenosied Rg3 and the ethanol extract of Artemisia asiatica. We have also found that certain anti-inflammatory phytochemicals exert inhibitory effects on phorbol ester-induced COX-2 expression and NF-$textsc{k}$B activation in immortalized human breast epithelial (MCF-10A) cells in culture. One of the plausible mechanisms undelying inhibition by aforementioned phytochemicals of phorbol ester-induced NF-$textsc{k}$B activation involves interference with degragation of the inhibitory unit, I$textsc{k}$Ba, which blocks subsequent nuclear translocation of the functionally active p65 subunit of NF-$textsc{k}$B. the activation of epidermal NF-$textsc{k}$B by phorbol ester and subsequent induction of COX-2 hence appear to play an important role in intracellular signaling pathwasy leading to tumor promotion and targeted inhibition of NF-$textsc{k}$B may provide a new promising cancer chemopreventive strategy.

• Biomolecules & Therapeutics
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• 제25권4호
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• pp.417-426
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• 2017

4-O-methylhonokiol, a neolignan compound from Magnolia Officinalis, has been reported to have various biological activities including hair growth promoting effect. However, although transforming growth factor-${\beta}$ (TGF-${\beta}$) signal pathway has an essential role in the regression induction of hair growth, the effect of 4-O-methylhonokiol on the TGF-${\beta}$ signal pathway has not yet been elucidated. We thus examined the effect of 4-O-methylhonokiol on TGF-${\beta}$-induced canonical and noncanonical pathways in HaCaT human keratinocytes. When HaCaT cells were pretreated with 4-O-methylhonokiol, TGF-${\beta}1$-induced G1/G0 phase arrest and TGF-${\beta}1$-induced p21 expression were decreased. Moreover, 4-O-methylhonokiol inhibited nuclear translocation of Smad2/3, Smad4 and Sp1 in TGF-${\beta}1$-induced canonical pathway. We observed that ERK phosphorylation by TGF-${\beta}1$ was significantly attenuated by treatment with 4-O-methylhonokiol. 4-O-methylhonokiol inhibited TGF-${\beta}1$-induced reactive oxygen species (ROS) production and reduced the increase of NADPH oxidase 4 (NOX4) mRNA level in TGF-${\beta}1$-induced noncanonical pathway. These results indicate that 4-O-methylhonokiol could inhibit TGF-${\beta}1$-induced cell cycle arrest through inhibition of canonical and noncanonical pathways in human keratinocyte HaCaT cell and that 4-O-methylhonokiol might have protective action on TGF-${\beta}1$-induced cell cycle arrest.

• 생명과학회지
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• 제20권9호
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• pp.1332-1338
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• 2010

사람 신경모세포종 세포주 SH-SY5Y에서 Fenretinide (FenR)에 의한 GD3합성효소(hST8Sia I)의 발현증가기작을 규명하게 위하여 hST8Sia I의 프로모터 활성을 조사해 본 결과 -1146에서 -646영역에서 FenR에 의한 활성증가를 나타내었다. 또한 부위특이적 변이의 분석은 -731에서 -722영역에 위치한 전사인자 NF-kB 결합부위가 hST8Sia I의 FenR에 의한 활성증가에 중요하게 관여하고 있음을 나타내었다. FenR에 의한 hST8Sia I 유전자의 발현유도에 포함된 신호전달기작을 전사인자 단백질의 항체를 이용하여 조사해 본 결과 FenR처리에 의해 세포질에서는 인산화된 AKT단백질 수준의 증가가 관찰되었고 핵내에서는 NF-kB의 p65단백질의 증가가 관찰되었다. 이러한 결과들은 FenR에 의한 hST8Sia I 유전자의 발현증가는 AKT신호전달경로에 의해 활성화된 NF-kB의 핵내로 이동하여 hST8Sia I 유전자의 프로모터에 결합함으로서 전사가 촉진되어 일어난다는 것을 나타낸다.

• Asian Pacific Journal of Cancer Prevention
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• 제15권5호
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• pp.1961-1970
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• 2014

Pyruvate kinase isozyme type M2 (PKM2) was first found in hepatocellular carcinoma (HCC), and its expression has been thought to correlate with prognosis. A large number of studies have demonstrated that epithelial-mesenchymal transition (EMT) is a crucial event in hepatocellular carcinoma (HCC) and associated metastasis, resulting in enhanced malignancy of HCC. However, the roles of PKM2 in HCC EMT and metastasis remain largely unknown. The present study aimed to determine the effects of PKM2 in EGF-induced HCC EMT and elucidate the molecular mechanisms in vitro. Our results showed that EGF promoted EMT in HCC cell lines as evidenced by altered morphology, expression of EMT-associated markers, and enhanced invasion capacity. Furthermore, the present study also revealed that nuclear translocation of PKM2, which is regulated by the ERK pathway, regulated ${\beta}$-catenin-TCF/LEF-1 transcriptional activity and associated EMT in HCC cell lines. These discoveries provide evidence of novel roles of PKM2 in the progression of HCC and potential therapeutic target for advanced cases.

• BMB Reports
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• 제41권2호
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• pp.170-175
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• 2008

In protein therapy, it is important for exogenous protein to be delivered into the target subcellular localization. To transduce a therapeutic protein into its specific subcellular localization, we synthesized nuclear localization signal (NLS) and membrane translocation sequence signal (MTS) peptides and produced a genetic in-frame SOD fusion protein. The purified SOD fusion proteins were efficiently transduced into mammalian cells with enzymatic activities. Immunofluorescence and Western blot analysis revealed that the SOD fusion proteins successfully transduced into the nucleus and the cytosol in the cells. The viability of cells treated with paraquat was markedly increased by the transduced fusion proteins. Thus, our results suggest that these peptides should be useful for targeting the specific localization of therapeutic proteins in various human diseases.

• 대한한의학방제학회지
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• 제24권4호
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• pp.243-257
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• 2016

Objectives : Illicium verum Hook. f. has been known to possess antimicrobial, antioxidant, antifungal, anti-inflammatory, insecticidal, analgesic, sedative, convulsive activities, it has been rarely conducted to evaluate the immuno-biological activity. The present study was examined to evaluate the anti-inflammatory effects of the Illicium verum Hook. f. water extracts (IVE) in vivo and in vitro. Methods : Cell viability was measured by MTT assay. The relative levels of NO were measured with Griess reagent. iNOS, COX-2, $NF-{\kappa}B$ and target proteins were detected by immunoblot analysis, and levels of cytokines were analyzed by ELISA kit. Anti-edema effect was determined in the carrageenan (CA)-induced paw edema model in rats. Results : All dosages of IVE used in MTT assay had no significant cytotoxicity. The increases of NO production and iNOS expression were detected in LPS-treated cells compared with control. However, these increases were attenuated by treatment with IVE. Also, IVE reduced the elevated production of $TNF-{\alpha}$, $IL-1{\beta}$ and IL-6 by LPS. IVE inhibited the $p-I{\kappa}B$ and translocation of $NF-{\kappa}B$ to nuclear. Furthermore, IVE significantly inhibited the increases of hind paw swelling, skin thicknesses and inflammatory cell infiltrations induced by CA injection. Therefore, IVE will be favorably inhibited the acute edematous inflammations. Conclusion : These results provide evidences that anti-inflammatory effect of IVE is partly due to the reduction of some inflammatory mediators by suppression of $NF-{\kappa}B$ pathway.

• 생명과학회지
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• 제23권8호
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• pp.1057-1063
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• 2013

진피(Citri Pericarpium)의 항암작용 기전 해석을 위하여 U937 백혈병 세포의 apoptosis 유발에 미치는 메탄올 추출물(EMCP)의 영향을 조사하였으며, apoptosis 조절에 중요한 몇 가지 유전자들의 발현 및 활성 변화, ROS의 생성 변화를 조사하였다. EMCP 처리에 의한 U937 세포의 증식 억제는 apoptosis 유도와 연관성이 있음을 DAPI 염색을 통한 apoptotic body 출현의 증가 및 Flow cytometry 분석에 의한 Sub-G1기 세포 빈도의 증가로 확인하였다. EMCP 처리에 의한 apoptosis 유도에서 Bax 발현 증가, caspases의 활성 및 PARP의 단편화 등이 동반되었으며, ROS 생성의 증가와 연관성이 있었다. 산화적 손상에 대해 세포나 조직을 보호하는 역할을 하는 것으로 알려진 세포 내 항산화 효소인 HO-1의 발현이 EMCP의 처리에 의해 증가되었으나 ROS 생성 억제제인 NAC의 전처리에 의해 감소된 HO-1의 발현은 전사인자인 Nrf2의 핵으로의 이동 억제와 관련되어 있었다. 이상의 결과에서 EMCP 처리에 의한 U937 세포의 apoptosis 유발에는 ROS 생성의 증가와 pNrf2에 의해 조절되는 HO-1의 발현 증가가 중요한 기전으로 작용한다는 것을 알 수 있었다. 이러한 자료는 진피의 항암기전 해석을 이해하는데 중요한 기초자료로서 활용될 수 있을 것으로 생각된다.

• Biomolecules & Therapeutics
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• 제26권2호
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• pp.146-156
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• 2018

Spermidine is a naturally occurring polyamine compound that has recently emerged with anti-aging properties and suppresses inflammation and oxidation. However, its mechanisms of action on anti-inflammatory and antioxidant effects have not been fully elucidated. In this study, the potential of spermidine for reducing pro-inflammatory and oxidative effects in lipopolysaccharide (LPS)-stimulated macrophages and zebrafish was explored. Our data indicate that spermidine significantly inhibited the production of pro-inflammatory mediators such as nitric oxide (NO) and prostaglandin $E_2$ ($PGE_2$), and cytokines including tumor necrosis $factor-{\alpha}$ and $interleukin-1{\beta}$ in RAW 264.7 macrophages without any significant cytotoxicity. The protective effects of spermidine accompanied by a marked suppression in their regulatory gene expression at the transcription levels. Spermidine also attenuated the nuclear translocation of $NF-{\kappa}B$ p65 subunit and reduced LPS-induced intracellular accumulation of reactive oxygen species (ROS) in RAW 264.7 macrophages. Moreover, spermidine prevented the LPS-induced NO production and ROS accumulation in zebrafish larvae and was found to be associated with a diminished recruitment of neutrophils and macrophages. Although more work is needed to fully understand the critical role of spermidine on the inhibition of inflammation-associated migration of immune cells, our findings clearly demonstrate that spermidine may be a potential therapeutic intervention for the treatment of inflammatory and oxidative disorders.

• 생명과학회지
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• 제30권7호
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• pp.634-639
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• 2020

불가사리는 다양한 생리활성물질을 가진 유용한 해양생물자원으로 알려져 있으나 불가사리가 가진 특유한 냄새로 인해 기능성 소재로 활용하는데 많은 제약이 있다. 우리는 최근에 로스팅을 통해 이러한 문제점을 해결하고 효율적인 화장품 소재로서의 활용 가능성을 제시하였으나 열처리된 불가사리 추출물의 생리활성에 관한 연구는 거의 전무한 실정이다. 따라서 본 연구에서는 LPS에 의해 염증을 유도한 Raw 264.7 세포에서 열처리 불가사리 추출물의 염증 조절 기전을 조사하여 항염증 소재로서의 활용 가능성을 확인하였다. 열처리 불가사리 추출물은 LPS에 의해 증가된 NO의 분비량과 iNOS의 발현을 현저히 감소시켰고 IL-1β와 IL-6와 같은 pro-inflammatory cytokine의 발현에서도 유의미한 감소를 나타내었다. 또한 열처리 불가사리 추출물에 의한 NF-κB p65 단백질의 핵으로의 전이 억제와 NF-κB 저해제인 PDTC와의 동시 처리에 의한 NO 분비량 감소는 열처리 불가사리 추출물의 NO 생성 저해 효과가 NF-κB 신호전달을 통해 이루어짐을 보여주었다. 본 연구 결과는 열처리 불가사리 추출물이 NF-κB 신호전달 경로를 통해 염증매개인자들의 발현을 억제하여 염증반응을 효과적으로 제어할 수 있는 잠재력을 가진 기능성 소재로서의 가능성을 제시하고 있다.

• 대한본초학회지
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• 제31권5호
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• pp.71-78
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• 2016

Objectives : Diabetic nephropathy is one of the most common chronic complications of diabetes and a leading cause of end-stage renal failure in the world. Mesangial cell proliferation is known as the major pathologic features such as glomerulosclerosis and renal fibrosis. Wiryeongtang (WRT) is a well-known traditional herbal formula as therapeutic agents for chronic edema and dysuresia of renal homeostasis. In the present study, we investigated whether WRT inhibits high glucose (HG)-induced renal dysfunction by TGF-β/Smads signal regulation in cultured mesangial cells.Methods : Inhibitory effect of WRT (10-50 ㎍/ml) on HG-stimulated mesangial cells proliferation and dysfunction were evaluated by [³H]-thymidine incorporation, Western blot, and RT-qPCR.Results : WRT significantly decreased HG-accelerated thymidine incorporation in human renal mesangial cell in a dose-dependent levels. WRT induced down-regulation of cyclins/CDKs and up-regulation of CDK inhibitor, p21waf1/cip1 and p27kip1 expression. In addition, HG enhanced expression of dysfunction biomarker such as collagen IV and CTGF, which was markedly attenuated by WRT. WRT decreased TGF-β1 and Smad-2/Smad-4 expression, whereas increased Smad-7 expression under HG. Furthermore, WRT inhibited HG-induced inflammatory factors level such as ICAM-1 and MCP-1 as well as NF-κB p65 nuclear translocation and intracellular ROS production.Conclusions : These results suggested that WRT may alleviate mesangial proliferation and inflammation possibly involved in renal fibrotic process, further diabetic nephropathy through disturbing TGF-β1/Smad signaling and NF-κB/ROS pathway. Thus, WRT might prove to be effective in the treatment of renal dysfunction leading to diabetic nephropathy.