Chung-Yi Chen

Anticancer Activity of Isoobtusilactone A from Cinnamomum kotoense : Involvement of Apoptosis, Cell-Cycle Dysregulation, Mitochondria Regulation, and Reactive Oxygen Species

In this study, we investigate the anticancer effect of isoobtusilactone A (IOA), a constituent isolated from the leaves of Cinnamomum kotoense, on human non-small cell lung cancer (NSCLC) A549 cells. IOA was found to induce the arrest of G2-M phase, induce apoptosis, increase sub-G1, and inhibit the growth of these cells. Further investigation revealed that IOAs blockade of the cell cycle was associated with increased levels of p21/WAF1, p27 (kip1), and p53. In addition, IOA triggered the mitochondrial apoptotic pathway, as indicated by an increase in Bax/Bcl-2 ratios, resulting in a loss of mitochondrial membrane potential, release of cytochrome c, activation of caspase-9 and caspase-3, and cleavage of PARP. We also found the generation of reactive oxygen species (ROS) to be a critical mediator in IOA-induced inhibition of A549 cell growth. In antioxidant and NO inhibitor studies, we found that by pretreating A549 cells with either N-acetylcystenine (NAC), catalase, mannitol, dexamethasone, trolox, or L-NAME we could significantly decrease IOA production of ROS. Moreover, using NAC to block ROS, we could significantly suppress IOA-induced antiproliferation, antimigration, and anti-invasion. Finally, we found that IOA inhibited the migration and invasion of A549 cell migration and invasion. Taken together, these results suggest that IOA has anticancer effects on A549 cells.

Anonaine Induces DNA Damage and Inhibits Growth and Migration of Human Lung Carcinoma H1299 Cells

The anticancer effects of (-)-anonaine were investigated in this current study. (-)-Anonaine at concentration ranges of 50-200 μM exhibited significant inhibition to cell growth and migration activities on human lung cancer H1299 cells at 24 h, albeit cell cycle analyses showed that (-)-anonaine at the above concentration ranges did not cause any significant changes in cell-cycle distributions. Significant nuclear damages of H1299 cells were observed with 10-200 μM (-)-anonaine treatment in a comet assay, whereas higher concentrations (6 and 30 mM) of (-)-anonaine concentrations were required to cause DNA damages in an in vitro plasmid cleavage assay. In summary, our results demonstrated that (-)-anonaine exhibited dose-dependent antiproliferatory, antimigratory, and DNA-damaging effects on H1299 cells. We inferred that (-)-anonaine can cause cell-cycle arrest and DNA damage to hamper the physiological behavior of cancer cells at 72 h, and therefore, it can be useful as one of the potential herbal supplements for chemoprevention of human lung cancer.

Cytotoxic compounds from the stems of Cinnamomum tenuifolium.

Three new butanolides, tenuifolide A (1), isotenuifolide A (2), and tenuifolide B (3), a new secobutanolide, secotenuifolide A (4), and one new sesquiterpenoid, tenuifolin (5), along with 16 known compounds were isolated from the stems of Cinnamomum tenuifolium. Their structures were determined by spectroscopic analyses. Compound 4 was found to induce apoptotic-related DNA damage, increase sub-G1 cells, and inhibit the growth of human prostate cancer cells, DU145. In addition, treatment with 4 significantly increased intracellular H2O2 and/or peroxide. The results show that 4 induced (a) noticeable reduction of mitochondrial transmembrane potential (DeltaPsim); (b) significant increase in the ratio of cytochrome c concentration (cytosol/mitochondria); and (c) subsequent activation of caspase-9/caspase-3. Antiproliferation caused by 4 was found to markedly decrease when pretreated with caspase-9/caspase-3 inhibitor. In ROS scavenging, antioxidant, NADPH oxidase, and NO inhibitor studies, pretreatment of DU145 cells with either DPI, dexamethasone, L-NAME, or mannitol decreased 4-induced intracellular DCF fluorescence of ROS. These results suggest that an increase of H2O2 and/or peroxide by 4 is the initial apoptotic event and 4 has anticancer effects on DU145 cells.

4-Shogaol, an Active Constituent of Dietary Ginger, Inhibits Metastasis of MDA-MB-231 Human Breast Adenocarcinoma Cells by Decreasing the Repression of NF-κB/Snail on RKIP

4-Shogaol is one of the phytoconstituents isolated from dried red ginger, which is commercially available to consumers. Some active constituents from ginger have been found to have anti-inflammatory and antioxidant effects, but studies on 4-shogaol have been relatively rare. This is the first report describing the antimetastasis activities of 4-shogaol and the possible mechanisms. This study determined that 4-shogaol inhibits the migration and invasion of MDA-MB-231 and causes mesenchymal-epithelial transition (MET). In addition, 4-shogaol suppresses the activation of NF-κB and cell migration and invasion induced by TNF-α. Furthermore, 4-shogaol has been shown to inhibit the phosphorylation of IκB and the translocation of NF-κB/Snail in MDA-MB-231. This study shows that RKIP, an inhibitory molecule of IKK, is up-regulated after 4-shogaol treatment and prolongs the inhibitory effects of 4-shogaol. Inhibition of RKIP by shRNA transfection significantly decreases the inhibitory effect of 4-shogaol on the NF-κB/Snail pathway, together with cell migration and invasion, whereas overexpression of Snail suppresses 4-shogaol-mediated metastasis inhibition and E-cadherin upregulation. Finally, the animal model revealed that 4-shogaol effectively inhibits metastasis of MDA-MB-231 in mice. This study demonstrates that 4-shogaol may be a novel anticancer agent for the the treatment of metastasis in breast cancer.

Larvicidal Constituents of Zingiber officinale (Ginger) against Anisakis simplex

In this study, we investigated the anthelmintic activity of [10]-shogaol, [6]-shogaol, [10]-gingerol and [6]-gingerol, compounds isolated from the roots of Zingiber officinale L., Zingiberaceae (ginger), against Anisakis simplex. The above compounds kill or reduce spontaneous movement in A. simplex larvae. The maximum lethal efficacy of [10]-shogaol and [10]-gingerol was approximately 80% and 100%, respectively. We further examined the time course of compound-induced loss of mobility in A. simplex. The results showed that various concentrations of [10]-shogaol, [6]-shogaol, [10]-gingerol and [6]-gingerol have maximum effects on loss of spontaneous movement from 24 to 72 h. In addition, the time course of mortality and the percentage of loss of spontaneous movements were ascertained to determine the minimum effective doses of [10]-gingerol and [10]-shogaol. [10]-Gingerol exhibited a larger maximum larvicidal effect and greater loss of spontaneous movement than [10]-shogaol and albendazole. In addition, these constituents of Zingiber officinale showed effects against 2,2-diphenyl-1-picrylhydrazyl (DPPH) and peroxyl radicals. These constituents of Zingiber officinale are responsible for its larvicidal activity against A. simplex.

Zingiber officinale (ginger) compounds have tetracycline‐resistance modifying effects against clinical extensively drug‐resistant Acinetobacter baumannii

Extensively drug‐resistant Acinetobacter baumannii (XDRAB) is a growing and serious nosocomial infection worldwide, such that developing new agents against it is critical. The antimicrobial activities of the rhizomes from Zingiber officinale, known as ginger, have not been proven in clinical bacterial isolates with extensive drug‐resistance. This study aimed to investigate the effects of four known components of ginger, [6]‐dehydrogingerdione, [10]‐gingerol, [6]‐shogaol and [6]‐gingerol, against clinical XDRAB. All these compounds showed antibacterial effects against XDRAB. Combined with tetracycline, they showed good resistance modifying effects to modulate tetracycline resistance. Using the 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) radical scavenging method, these four ginger compounds demonstrated antioxidant properties, which were inhibited by MnO2, an oxidant without antibacterial effects. After the antioxidant property was blocked, their antimicrobial effects were abolished significantly. These results indicate that ginger compounds have antioxidant effects that partially contribute to their antimicrobial activity and are candidates for use in the treatment of infections with XDRAB. Copyright

[6]-gingerol induces Ca2+ mobilization in Madin-Darby canine kidney cells.

[6]-gingerol, a major phenolic compound derived from ginger (Zingiber officinale), is a potential chemopreventive compound that can induce stress in cancer cells and cause apoptotic cell death. This study examines the early signaling effects of [6]-gingerol on renal cells. It was found that [6]-gingerol caused a slow and sustained rise of [Ca2+]i in a concentration-dependent manner. [6]-gingerol also induced a [Ca2+]i rise when extracellular Ca2+ was removed, but the magnitude was reduced by 80%. Depletion of intracellular Ca2+ stores with CCCP, a mitochondrial uncoupler, did not affect the action of [6]-gingerol. In a Ca2+-free medium, the [6]-gingerol-induced [Ca2+]i rise was partially abolished by depleting stored Ca2+ with thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor). The elevation of [6]-gingerol-caused [Ca2+]i in a Ca2+-containing medium was not affected by modulation of protein kinase C activity. The [6]-gingerol-induced Ca2+ influx was blocked by nicardipine. U73122, an inhibitor of phospholipase C, abolished ATP (but not [6]-gingerol)-induced [Ca2+]i rise. These findings suggest that [6]-gingerol induces a significant rise in [Ca2+]i in MDCK renal tubular cells by stimulating both extracellular Ca2+ influx and thapsigargin-sensitive intracellular Ca2+ release via as yet unidentified mechanisms.

10-Shogaol, an Antioxidant from Zingiber officinale for Skin Cell Proliferation and Migration Enhancer

In this work, one of Zingiber officinale components, 10-shogaol, was tested with 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, metal chelating ability, and reducing power to show antioxidant activity. 10-Shogaol promoted human normal epidermal keratinocytes and dermal fibroblasts cell growths. 10-Shogaol enhanced growth factor production in transforming growth factor-β (TGF-β), platelet derived growth factor-αβ (PDGF-αβ) and vascular endothelial growth factors (VEGF) of both cells. In the in vitro wound healing assay for 12 or 24 h, with 10-shogaol, the fibroblasts and keratinocytes migrated more rapidly than the vehicle control group. Thus, this study substantiates the target compound, 10-shogaol, as an antioxidant for human skin cell growth and a migration enhancer with potential to be a novel wound repair agent.

Antioxidant and Anticancer Aporphine Alkaloids from the Leaves of Nelumbo nucifera Gaertn. cv. Rosa-plena

Fifteen compounds were extracted and purified from the leaves of Nelumbo nucifera Gaertn. cv. Rosa-plena. These compounds include liriodenine (1), lysicamine (2), (−)-anonaine (3), (−)-asimilobine (4), (−)-caaverine (5), (−)-N-methylasimilobine (6), (−)-nuciferine (7), (−)-nornuciferine (8), (−)-roemerine (9), 7-hydroxydehydronuciferine (10) cepharadione B (11), β-sitostenone (12), stigmasta-4,22-dien-3-one (13) and two chlorophylls: pheophytin-a (14) and aristophyll-C (15). The anti-oxidation activity of the compounds was examined by antiradical scavenging, metal chelating and ferric reducing power assays. The results have shown that these compounds have antioxidative activity. The study has also examined the antiproliferation activity of the isolated compounds against human melanoma, prostate and gastric cancer cells. The results shown that 7-hydroxydehydronuciferine (10) significantly inhibited the proliferation of melanoma, prostate and gastric cancer cells. Together, these findings suggest that leaves of Nelumbo nucifera Gaertn. cv. Rosa-plena are a good resource for obtaining the biologically active substances with antioxidant properties.

Biofunctional Constituents from Liriodendron tulipifera with Antioxidants and Anti-Melanogenic Properties

From the stems of Liriodendron tulipifera, seventeen known compounds have been extracted, isolated and purified. By using spectroscopic analysis, the structures of these pure constituents were determined as three lignans, four steroids and ten benzenoids. Identified compounds were screened for antioxidant abilities using: 1,1-diphenyl-2-picrylhydrazul (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) scavenging free radical activity assays; metal chelating power test; and ferric reducing/antioxidant power (FRAP) examination. The result revealed that seventeen compounds had potential anti-oxidative capabilities. In addition, the anti-tyrosinase effect was determined by calculating the hydroxylation of L-tyrosine to L-dopa and the oxidization of L-dopa to dopaquinone, according to in vitro mushroom tyrosinase evaluation platform. Furthermore, based on assays on B16F10 cell line, our data suggest that five compounds isolated from L. tulipifera would be able to inhibit tyrosinase activity and reduce the melanin content in animal cells. Therefore, some of the examined compounds could be potentially used in the cosmetic skin whitening business, therapeutic applications or the food industry.