• Molecules and Cells
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• 제38권4호
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• pp.327-335
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• 2015

Piperlongumine, a natural alkaloid isolated from the long pepper, selectively increases reactive oxygen species production and apoptotic cell death in cancer cells but not in normal cells. However, the molecular mechanism underlying piperlongumine-induced selective killing of cancer cells remains unclear. In the present study, we observed that human breast cancer MCF-7 cells are sensitive to piperlongumine-induced apoptosis relative to human MCF-10A breast epithelial cells. Interestingly, this opposing effect of piperlongumine appears to be mediated by heme oxygenase-1 (HO-1). Piperlongumine upregulated HO-1 expression through the activation of nuclear factor-erythroid-2-related factor-2 (Nrf2) signaling in both MCF-7 and MCF-10A cells. However, knockdown of HO-1 expression and pharmacological inhibition of its activity abolished the ability of piperlongumine to induce apoptosis in MCF-7 cells, whereas those promoted apoptosis in MCF-10A cells, indicating that HO-1 has anti-tumor functions in cancer cells but cytoprotective functions in normal cells. Moreover, it was found that piperlongumine-induced Nrf2 activation, HO-1 expression and cancer cell apoptosis are not dependent on the generation of reactive oxygen species. Instead, piperlongumine, which bears electrophilic ${\alpha},{\beta}$-unsaturated carbonyl groups, appears to inactivate Kelch-like ECH-associated protein-1 (Keap1) through thiol modification, thereby activating the Nrf2/HO-1 pathway and subsequently upregulating HO-1 expression, which accounts for piperlongumine-induced apoptosis in cancer cells. Taken together, these findings suggest that direct interaction of piperlongumine with Keap1 leads to the upregulation of Nrf2-mediated HO-1 expression, and HO-1 determines the differential response of breast normal cells and cancer cells to piperlongumine.

• Journal of Microbiology and Biotechnology
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• 제12권4호
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• pp.679-682
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• 2002

The alkaloids, piperlongumine, piperine, pipernonaline, and piperoctadecalidine, isolated from Piper longum L., were found to inhibit the biosynthesis of aflatoxin $B_1$ (AF$B_1$) in Aspergillus flavus WRRC 3-90-42-12. Piperlongumine was the most active among the compounds tested, with a 96% inhibition of AF$B_1$biosynthesis at 0.2% (w/v) supplement in a potato dextrose agar (PDA) medium. The three other piperidine alkaloids, pipeline, pipernonaline, and piperoctadecalidine, also inhibited the biosynthesis of AF$B_1$. Of these three alkaloids, piperoctadecalidine exhibited a potent inhibitory activity with a 100% inhibition of AF$B_1$ production at 0.7% (w/v) supplement in a PDA medium. Therefore, piperlongumine and piperoctadecalidine could be used as antiaflatoxigenic agents in agricultural industries. To determine the antiaflatoxigenic mode of action of piperlongumine, further studies are needed.

• Molecules and Cells
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• 제42권12호
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• pp.884-892
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• 2019

Piperlongumine (PL), a natural alkaloid compound isolated from long pepper (Piper longum), can selectively kill cancer cells, but not normal cells, by accumulation of reactive oxygen species (ROS). The objective of this study was to investigate functional roles of expression of SETDB1 and FosB during PL treatment in MCF7 breast cancer cells. PL downregulates SETDB1 expression, and decreased SETDB1 expression enhanced caspase 9 dependent-PARP cleavage during PL-induced cell death. PL treatment generated ROS. ROS inhibitor NAC (N-acetyl cysteine) recovered SETDB1 expression decreased by PL. Decreased SETDB1 expression induced transcriptional activity of FosB during PL treatment. PARP cleavage and positive annexin V level were increased during PL treatment with FosB overexpression whereas PARP cleavage and positive annexin V level were decreased during PL treatment with siFosB transfection, implying that FosB might be a pro-apoptotic protein for induction of cell death in PL-treated MCF7 breast cancer cells. PL induced cell death in A549 lung cancer cells, but molecular changes involved in the induction of these cell deaths might be different. These results suggest that SETDB1 mediated FosB expression may induce cell death in PL-treated MCF7 breast cancer cells.

• Applied Biological Chemistry
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• 제46권4호
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• pp.361-366
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• 2003

필발 열매로부터 추출 및 분리한 piperlongurnine (1-[3-(3,4,5-trimethoxyphenyl)acryloyl]-5,6-dihydro-1H-pyridin-2-one)이 aflatoxin $B_1\;(AFB_1)$ 생성억제에 있어서 탁월한 효과가 입증되어 3,4,5-trimethoxycinnamic acid (TMCA)를 모체로 하여 1-piperidin-1-yl-3-(3,4,5-trimethoxyphenyl)propenone (1), 1-morpholin-4-yl-3-(3,4,5-trimetholfrphenyl)propenone (2), 1- (3,5-dimethylpiperidin-1-yl)-3-(3,4,5-trimethoxyphenyl)propenone (3), 1-(2-methylperidin-1-yl)-3-(3,4,5-trimethoxyphenyl)propenone (4), 1- (3-hydroxypiperidin-1-yl)-3-(3,4,5-trimethoxyphenyl)propenone (5), 1-[3-(3,4,5-trimethoxy-phenyl)acryloyl]piperidin-2-one (6) 및 ethyl 1-[3-(3,4,5-trimethoxyphenyl)acryloyl]piperidin-4-carboxylate (7)의 유도체를 합성하여 구조를 확인하고, 이 화합물들을 이용하여 $AFB_1$ 생성저해 효과를 측정하였다. Aspergillus flavus NRRL 2061로부터 생성되는 $AFB_1$ 생성저해에 대한 실험한 결과 모든 유도체 화합물에서 활성을 나타내었으며, 특히 화합물 (3)이 1000, 500, 250, 100및 $50\;{\mu}g/ml$에서 100, 95, 90, 53 및 10%의 생성저해를 나타냈다. 이러한 연구 결과 유도체 화합물 (3)은 항진균 독소제 개발을 위한 선도화합물로 이용하여 새로운 농약으로 개발이 가능할 것이라고 판단된다.

• International Journal of Oral Biology
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• 제44권3호
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• pp.89-95
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• 2019

Piperlongumine (PL) is a natural product found in long pepper (Piper longum). The pharmacological effects of PL are well known, and it has been used for pain, hepatoprotection, and asthma in Oriental medicine. No studies have examined the effects of PL on bone tissue or bone-related diseases, including osteoporosis. The current study investigated for the first time the inhibitory effects of PL on osteoclast differentiation, bone resorption, and osteoclastogenesis-related factors in RAW264.7 macrophages stimulated by the receptor activator for nuclear factor-${\kappa}B$ ligand (RANKL). Cytotoxicity was examined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and osteoclast differentiation and bone resorption were confirmed by tartrate-resistant acid phosphatase (TRAP) staining and pit formation analysis. Osteoclast differentiation factors were confirmed by western blotting. PL exhibited toxicity in RAW264.7 macrophages, inhibiting osteoclast formation and bone resorption, in addition to inhibiting the expression of osteoclastogenesis-related factors, such as tumor necrosis factor receptor-associated factor 6 (TRAF6), c-Fos, and NFATc1, in RANKL-stimulated RAW264.7 macrophages. These findings suggest that PL is suitable for the treatment of osteoporosis, and it serves as a potential therapeutic agent for various bone diseases.

• 한국식품위생안전성학회:학술대회논문집
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• 한국식품위생안전성학회 2003년도 추계 국제심포지움 및 학술발표회
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• pp.53-57
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• 2003

• Asian Pacific Journal of Cancer Prevention
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• 제15권7호
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• pp.3211-3217
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• 2014

Background: The current study investigated the effects of Piper longumine on radio-sensitization of human breast cancer MDA-MB-231 cells and underlying mechanisms. Materials and Methods: Human breast cancer MDA-MB-231 cells were cultured in vitro and those in logarithmic growth phase were selected for experiments divided into four groups: control, X-ray exposed, Piper longumine, and Piper longumine combined with X-rays. Conogenic assays were performed to determine the radio-sensitizing effects. Cell survival curves were fitted by single-hit multi-target model and then the survival fraction (SF), average lethal dose ($D_0$), quasi-threshold dose ($D_q$) and sensitive enhancement ratio (SER) were calculated. Cell apoptosis was analyzed by flow cytometry (FCM). Western blot assays were employed for expression of apoptosis-related proteins (Bc1-2 and Bax) after treatment with Piper longumine and/or X-ray radiation. The intracellular reactive oxygen species (ROS) level was detected by FCM with a DCFH-DA probe. Results: The cloning formation capacity was decreased in the group of piperlongumine plus radiation, which displayed the values of SF2, D0, Dq significantly lower than those of radiation alone group and the sensitive enhancement ratio (SER) of D0 was1.22 and 1.29, respectively. The cell apoptosis rate was increased by the combination treatment of Piper longumine and radiation. Piper longumine increased the radiation-induced intracellular levels of ROS. Compared with the control group and individual group, the combination group demonstrated significantly decreased expression of Bcl-2 with increased Bax. Conclusions: Piper longumine at a non-cytotoxic concentration can enhance the radio-sensitivity of MDA-MB-231cells, which may be related to its regulation of apoptosis-related protein expression and the increase of intracellular ROS level, thus increasing radiation-induced apoptosis.

• 생명과학회지
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• 제31권10호
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• pp.929-936
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• 2021

본 연구에서는 시판하는 천연물 library (Selleckchem, L1400)로부터 암세포 항 성장 활성을 보여주는 천연물을 선별하였다. 즉, 인간 대장암 세포주인 HCT116에 50 μM의 각 천연물을 처리한 후 세포 생존율을 측정하였다. 1차 선별과정을 통하여 5종의 천연물(chrysin, diosmetin, emodin, piperlongumine, tanshinone I)을 선별하였다. 5종의 천연물에 의한 NAG-1 단백질의 발현을 확인한 결과 chrysin과 emodin에 의해서 발현이 현저하게 증가하였다. 또한, chrysin과 emodin은 농도의존적으로 세포 생존율을 감소시켰으며, chrysin과 emodin은 항암 단백질인 NAG-1의 발현을 농도 및 시간 의존적으로 증가시켰다. 게다가, chrysin과 emodin 처리에 의해 증가된 PARP cleavage가 NAG-1 siRNA transfection에 의해서 감소됨을 확인함으로써, chrysin과 emodin에 의한 세포사멸과 NAG-1의 발현 증가가 직접적인 관련이 있음을 증명하였다. 따라서, 본 연구결과는 암세포 항 성장 활성을 보여주는 천연물 선별에 대한 기초 데이터를 제공해 주며, chrysin과 emodin에 의한 암세포 항 성장 활성 및 세포사멸의 기전을 이해하는 데 도움을 줄 것으로 판단된다.

• Asian Pacific Journal of Cancer Prevention
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• 제15권19호
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• pp.8041-8046
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• 2014

In-depth analysis of how TRAIL signals through death receptors to induce apoptosis in cancer cells using high throughput technologies has added new layers of knowledge. However, the wealth of information has also highlighted the fact that TRAIL induced apoptosis may be impaired as evidenced by experimental findings obtained from TRAIL resistant cancer cell lines. Overwhelmingly, increasing understanding of TRAIL mediated apoptosis has helped in identifying synthetic and natural compounds which can restore TRAIL induced apoptosis via functionalization of either extrinsic or intrinsic pathways. Increasingly it is being realized that biologically active phytochemicals modulate TRAIL induced apoptosis, as evidenced by cell-based studies. In this review we have attempted to provide an overview of how different phytonutrients have shown efficacy in restoring apoptosis in TRAIL resistant cancer cells. We partition this review into how the TRAIL mediated signaling landscape has broadened over the years and how TRAIL induced signaling machinery crosstalks with autophagic protein networks. Subsequently, we provide a generalized view of considerable biological activity of coumarins against a wide range of cancer cell lines and how coumarins (psoralidin and esculetin) isolated from natural sources have improved TRAIL induced apoptosis in resistant cancer cells. We summarize recent updates on piperlongumine, phenethyl isothiocyanate and luteolin induced activation of TRAIL mediated apoptosis. The data obtained from pre-clinical studies will be helpful in translation of information from benchtop to the bedside.