• Journal of Pharmaceutical Investigation
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• v.38 no.4
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• pp.241-247
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• 2008

Paclitaxel is a taxane diterpene amide, which was first extracted from the stem bark of the western yew, Taxus brevifolia. This natural product has proven to be useful in the treatment of a variety of human neoplastic disorders, including ovarian cancer, breast and lung cancer. Paclitaxel is a highly hydrophobic drug that is poorly soluble in water. It is mainly given by intravenous administration. Therefore, The pharmaceutical formulation of paclitaxel ($Taxol^{(R)}$; Bristol-Myers Squibb) contains 50% $Cremophor^{(R)}$ EL and 50% dehydrated ethanol. However the ethanol/Cremophor EL vehicle required to solubilize paclitaxel in $Taxol^{(R)}$ has a pharmacological and pharmaceutical problems. To overcome these problems, new formulations for paclitaxel that do not require solubilization by $Cremophor^{(R)}$ EL are currently being developed. Therefore this study utilized a supercritical fluid antisolvent (SAS) process for cremophor-free formulation. To select hydrophilic polymers that require solubilization for paclitaxel, we evaluated polymers and the ratio of paclitaxel/polymers. HP-${\beta}$-CD was used as a hydrophilic polymer in the preparation of the paclitaxel solid dispersion. Although solubility of paclitaxel by polymers was increased, physical stability of solution after paclitaxel/polymer powder soluble in saline was unstable. To overcome this problem, we investigated the use of surfactants. At 1/20/40 of paclitaxel/hydrophilic polymer/ surfactant weight ratio, about 10 mg/mL of paclitaxel can be solubilized in this system. Compared with the solubility of paclitaxel in water ($1\;{\mu}g/mL$), the paclitaxel solid dispersion prepared by SAS process increased the solubility of paclitaxel by near 10,000 folds. The physicochemical properties was also evaluated. The particle size distribution, melting point and amophorization and shape of the powder particles were fully characterized by particle size distribution analyzer, DSC, SEM and XRD. In summary, through the SAS process, uniform nano-scale paclitaxel solid dispersion powders were obtained with excellent results compared with $Taxol^{(R)}$ for the physicochemical properties, solubility and pharmacokinetic behavior.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.6
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• pp.2439-2445
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• 2014

Cryptotanshinone (CPT), is a quinoid diterpene isolated from the root of the Asian medicinal plant, Salvia miotiorrhiza bunge. Numerous researchers have found that it could work as a potent antitumor agent to inhibit tumor growth in vitro, buith there has been much less emphasis on its in vivo role against breast tumors. Using a mouse tumor model of MCF7 cells, we showed that CPT strongly inhibited MCF7 cell growth in vivo with polarization of immune reactions toward Th1-type responses, stimulation of naive CD4+ T cell proliferation, and also increased IFN-${\gamma}$ and perforin production of CD4+ T cells in response to tumor-activated splenocytes. Furthermore, data revealed that the cytotoxic activity of CD4+ T cells induced by CPT was markedly abrogated by concanamycin A(CMA), a perforin inhibitor, but not IFN-${\gamma}$ Ab. On the other hand, after depletion of CD4+ T cells or blocked perforin with CMA in a tumor-bearing model, CPT could not effectively suppress tumor growth, but this phenomenon could be reversed by injecting naive CD4+ T cells. Thus, our results suggested that CPT mainly inhibited breast tumor growth through inducing cytotoxic CD4+ T cells to secrete perforin. We further found that CPT enhanced perforin production of CD4+ T cells by up-regulating JAK2 and STAT4 phosphorylation. These findings suggest a novel potential therapeutic role for CPT in tumor therapy, and demonstrate that CPT performs its antitumor functions through cytotoxic CD4+ T cells.

• YAKHAK HOEJI
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• v.41 no.2
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• pp.161-173
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• 1997

Tuber of Aconitum chiisanense(Ranunculaceae) a specific medicinal plant in Korea, which is known to have the activity to recover reduced metabolism of feeble patients and has been used to symptoms such as pain, paralysis, atonia and coldness of extremities, etc. were studied. The powdered tubers of the plant were extracted with 10% EtOH 3 times and the combined extract was dissolved in 1N HCl solution and washed with ethyl acetate. The aqueous layer was basified with solid $Na_2CO_3$ and extracted with $CHCl_3$ to obtain an alkaloidal fraction. The alkaloidal fraction was subjected to column chromatography using silica gel, alumina and Sephdex LH 20, etc. From the alkaloidal fraction, five diterpene alkaloids, mesaconitine, aconitine, hypaconitine, 8-O-ethyl 14-benzoylmesaconine and talatizamine, were isolated and identified on the basis of their physico-chemical properties and spectroscopic evidences($^1H$-, $^{13}C$-NMR, EI-MS, IR, 2D-NMR) respectively. Especially the Compound IV, 8-O-ethyl 14-benzoylmesaconine, was assumed to be an artifact resulting from mesaconitine during extraction procedures. The contents of mesaconitine, aconitine and hypaconitine in the mother tuber of this plant were 0.300%, 0.024%, and 0.068%. And that of the attached tuber(new one) of this plant were 0.336%, 0.034% and 0.240% respectively.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2000.04a
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• pp.10-14
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• 2000

The cycloooxygenase enzymes catalyze the oxidative conversion of arachidonic acid into prostag1andin H$_2$Which mediates both benificial and pathological effects. The COX-1 is constitutively expressed in most tissues and in blood platelets wherease the expression of COX-2 isoform is induced in response to inflmmatory stimuli such as cyctokynes. Thus the identification of a novel COX-2 selective inhibitor should offer excellent antiinflammatory activity with minimal side effects such as gastrointestinal toxicity. Recently, a group of structurally unique and biologically active pimarane diterpenoids has been isolated from indigenous Korean medicinal plants. These new diterpenoids turned out to be potential analgesic and antiinflammatory agent due to their potent inhibitory activities of prostaglandin synthesis. We have also found that the inhibition of PGE$_2$synthesis is attributed to the potent COX inhibition by pimarane diterpenoid in arachidonic acid cascade. In conjunction with development of new analgesic and nonsteroidal antiinflammatory agent, a series of works on these diterpenoids have been extensively carried out in our laboratories. These efforts involve the structure-activity relationship of pimaradienoic acid, molecular modelings and COX inibitory activities as well as actiinflammatory effects of its structural analogues. In addition, the total syntheses of the new natural pimarane diterpenoids, their stereoisomers and other structural variants were intensively investigated.

• The Korean Journal of Food And Nutrition
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• v.30 no.1
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• pp.156-165
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• 2017

This study investigated the chemical composition of Petasites japonicus (S. et Z.) Maxim essential oil. During the period 2011~2013, P. japonicus (S. et Z.) Maxim plant was investigated for composition of the essential oil. Chemical composition and characteristic compounds of the essential oils from the aerial parts of the plant according to the crop year studied. The essential oils consisted of sesquiterpene compounds, which were the most abundant components. Samples collected in 2011 were found to be richer in oxygenated sesquiterpenes, while samples collected in 2012 and 2013 were richer in diterpene alcohols and sesquiterpene hydrocarbons, respectively. Ninety-two compounds were identified in the P. japonicus (S. et Z.) Maxim essential oil of 2011, and caryophyllene oxide (20.49%), ${\beta}$-caryophyllene (10.28%), ${\beta}$-bisabolene (6.80%), and alloaromadendrene (6.50%) were the major compounds. Seventy-four compounds were identified in the plant essential oil of 2012, and phytol (17.22%), ${\alpha}$-farnesene (15.31%), ${\alpha}$-caryophyllene (9.93%), and ${\beta}$-caryophyllene (6.12%) were the major compounds. Ninety-two compounds were identified in the plant essential oil of 2013, and ${\alpha}$-farnesene (22.42%), ${\alpha}$-caryophyllene (21.49%), pentadecane (15.35%), and germacrene (5.70%) were the major compounds. The content of most of the chemical constituents varied significantly with different harvesting time. The content of ${\alpha}$-caryophyllene and caryophyllene oxide was increased significantly from 2011 to 2013. The content of ${\alpha}$-caryophyllene and isocaryophyllene was decreased significantly from 2011 to 2013.

• BMB Reports
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• v.38 no.4
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• pp.391-398
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• 2005

3-hydrogenwadaphnin (3-HK) is a new daphnane-type diterpene ester isolated from Dendrostellera lessertii with strong anti-tumoral activity in animal models and in cultures. Here, prolonged effects of this new agent on proliferation and viability of several different cancerous cell lines were evaluated. Using [$^3H$]thymidine incorporation, it was found that the drug inhibited cell proliferation and induced G1/S cell cycle arrest in leukemic cells 24 h after a single dose treatment. The cell viability of Jurkat cells was also decreased by almost 10%, 31% and 40% after a single dose treatment (7.5 nM) at 24, 48 and 72 h, respectively. The drug-treated cells were stained with acridine orange/ethidium bromide to document the chromatin condensation and DNA fragmentation. These observations were further confirmed by detection of DNA laddering pattern in the agarose gel electrophoresis of the extracted DNA from the treated cells. Treatment of K562 cells with the drug at 7.5, 15 and 30 nM caused apoptosis in 25%, 45% and 65% of the cells, respectively. Exogenous addition of $25-50\;{\mu}M$ guanosine and/or deoxyguanosine to the cell culture of the drug-treated cells restored DNA synthesis, released cell arrest at G1/S checkpoint and decreased the apoptotic cell death caused by the drug. These observations were not made using adenosine. However, the drug effects on K562 cells were potentiated by hypoxanthine. Based on these observations, perturbation of GTP metabolism is considered as one of the main reasons for apoptotic cell death by 3-HK.

• BMB Reports
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• v.39 no.6
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• pp.722-729
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• 2006

Recently, we have reported that 3-hydrogenkwadaphnin (3-HK), a diterpene ester isolated from Dendrostellera lessertii (Thymealeaceae), is very effective against leukemia cell lines without any detectable effects on normal cells (Moosavi et al., 2005b). In this study, we report that 3-HK induces $G_1$ cell-cycle arrest, differentiation and apoptosis in APL NB4 cell line. Indeed, the drug between 24 to 96 h induced 7-65% growth inhibition of NB4 cells. Cell viability was also decreased by 2-55% between 24 to 96 h treatments with the drug, respectively. These effects of the drug were also dose-dependent. According to flow cytomtry results, 3-HK (15 nM) induced a significant G1-arrest up to 24 h which was consequently followed with appearance of sub-$G_1$ peak at 72 to 96 h. Hoechst 33258 staining and DNA fragmentation assays confirmed the occurrence of apoptosis among the treated cells. On the other hand, NBT reducing assay, Wright-Giemsa staining, phagocytic activity and expression of cell surface markers (CD11b and CD14) confirmed that the inhibition of proliferation is associated with differentiation especially toward macrophage-like morphology. Interestingly, 3-HK at 5 and 10 nM enhanced the effects of all-trans retinoic acid (ATRA) in NB4 cells. Based on these results, 3-HK might become an ideal candidate for treatment of APL patients pending full exploration of its biological functions.

• BMB Reports
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• v.38 no.6
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• pp.668-675
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• 2005

A full-length cDNA encoding taxadiene synthase (designated as TmTXS), which catalyzes the first committed step in the Taxol biosynthetic pathway, was isolated from young leaves of Taxus media by rapid amplification of cDNA ends (RACE). The full-length cDNA of TmTXS had a 2586 bp open reading frame (ORF) encoding a protein of 862 amino acid residues. The deduced protein had isoelectric point (pI) of 5.32 and a calculated molecular weight of about 98 kDa, similar to previously cloned diterpene cyclases from other Taxus species such as T. brevifolia and T. chinenisis. Sequence comparison analysis showed that TmTXS had high similarity with other members of terpene synthase family of plant origin. Tissue expression pattern analysis revealed that TmTXS expressed strongly in leaves, weak in stems and no expression could be detected in fruits. This is the first report on the mRNA expression profile of genes encoding key enzymes involved in Taxol biosynthetic pathway in different tissues of Taxus plants. Phylogenetic tree analysis showed that TmTXS had closest relationship with taxadiene synthase from T. baccata followed by those from T. chinenisis and T. brevifolia. Expression profiles revealed by RT-PCR under different chemical elicitor treatments such as methyl jasmonate (MJ), silver nitrate (SN) and ammonium ceric sulphate (ACS) were also compared for the first time, and the results revealed that expression of TmTXS was all induced by the tested three treatments and the induction effect by MJ was the strongest, implying that TmTXS was high elicitor responsive.

• Biomolecules & Therapeutics
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• v.24 no.6
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• pp.623-629
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• 2016

(1S,2S,3E,7E,11E)-3,7,11,15-cembratetraen-17,2-olide (LS-1), a marine cembrenolide diterpene, has anticancer activity against colon cancer cells such as HT-29, SNU-C5/5-FU (fluorouracil-resistant SNU-C5) and SNU-C5. However, the action mechanism of LS-1 on SNU-C5 human colon cancer cells has not been fully elucidated. In this study, we investigated whether the anticancer effect of LS-1could result from apoptosis via the modulation of $Wnt/{\beta}$-catenin and the TGF-${\beta}$ pathways. When treated with the LS-1, we could observe the apoptotic characteristics such as apoptotic bodies and the increase of sub-G1 hypodiploid cell population, increase of Bax level, decrease of Bcl-2 expression, cleavage of procaspase-3 and cleavage of poly (ADP-ribose) polymerase in SNU-C5 cells. Furthermore, the apoptosis induction of SNU-C5 cells upon LS-1 treatment was also accompanied by the down-regulation of $Wnt/{\beta}$-catenin signaling pathway via the decrease of GSK-$3{\beta}$ phosphorylation followed by the decrease of ${\beta}$-catenin level. In addition, the LS-1 induced the activation of TGF-${\beta}$ signaling pathway with the decrease of carcinoembryonic antigen which leads to decrease of c-Myc, an oncoprotein. These data suggest that the LS-1 could induce the apoptosis via the down-regulation of $Wnt/{\beta}$-catenin pathway and the activation of TGF-${\beta}$ pathway in SNU-C5 human colon cancer cells. The results support that the LS-1 might have potential for the treatment of human colon cancer.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.4
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• pp.456-461
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• 2012

The leaves of $Stevia$ $rebaudiana$ are well-known in Japan, Korea, and China as a natural sweetener. Medicinal uses of this plant originated in Paraguay and Brazil in the form of aqueous decoctions of the leaves used as a contraceptive agent and for the treatment of hyperglycemia. In the present study, the antioxidant, anti-hypertension, and anti-inflammatory activities of $S.$ $rebaudiana$ extracts are investigated for their use in food. The biologically-active compound was isolated and purified from $S.$ $rebaudiana$. The isolated compound was identified as austroinulin ($C_{20}H_{34}O_3$; molecular weight 322) by mass, IR spectrophotometry, 1D, and 2D-NMR. Austroinulin was characterized as a diterpenoid possessing a 3-methylpenta-2,4-dienyl at C-9. When subjected to an inflammatory mediator inhibitory assay from lipopolysaccharide (LPS)-activated macrophages, the austroinulin inhibited the enhanced production of nitric oxide (NO) and inducible nitric oxide synthase (iNOS) expression (10 ${\mu}g$/mL＝67.9 and 45.1%, respectively). This was significant and dose-dependent. The results suggest that austroinulin from $S.$ $rebaudiana$ inhibited the NO and iNOS in RAW 264.7 cells.