Eupatilin, a pharmacologically active flavone derived from Artemisia plants, induces apoptosis in human promyelocytic leukemia cells

Pancreatic stellate cells: new target in the treatment of chronic pancreatitis

Chronic pancreatitis (CP) is characterized by progressive fibrosis, pain and/or loss of exocrine and endocrine functions. Recent in vitro and in vivo experiments have proven objectively the role of activated pancreatic stellate cells (PSC) in fibrogenesis in CP. Molecular mediators shown to regulate the pathogenesis include transforming growth factor beta (TGF-beta), platelet-derived growth factor (PDGF), and pro-inflammatory cytokines such as IL-1, IL-6 and TNF-alpha. Furthermore, molecular pathways involving mitogen-activated protein kinases (MAPK), phosphatidyl inositol 3-kinase (PI3K), Ras superfamily G proteins, serine threonine protein kinase Raf-1 and peroxisome proliferator activated receptor gamma (PPAR-gamma) have been elucidated. Understanding of the pathogenesis has led to identification of novel molecular targets and development of potential newer therapeutic agents. Those found to retard the progression of experimental CP and fibrosis in animal models include interferon (IFN) beta and IFN-gamma; a Japanese herbal medicine called Saiko-keishi-to (TJ-10); curcumin; PPAR-gamma ligand (troglitazone); antioxidants (vitamin A, vitamin E, DA 9601 and epigallocatechin-3-gallate); a protease inhibitor (camostat mesilate) and hydroxymethylglutaryl-CoA inhibitor (lovastatin). This review summarizes the current literature addressing the role of different pharmacological agents aimed at reducing or preventing inflammation and the consequent fibrogenesis in CP.

Gastroprotective effects of DA-6034, a new flavonoid derivative, in various gastric mucosal damage models

This study evaluated the gastroprotective activity of DA-6034 against various ulcerogens including ethanol, aspirin, indomethacin, stress, and acetic acid. The basic mechanisms of DA-6034 as a defensive factor such as mucus secretion and endogenous prostaglandin E(2) synthesis were determined. Rats with gastric lesions induced by ethanol-HCl, aspirin, indomethacin, and stress that had been pretreated with DA-6034 orally showed a statistically significant decrease or decreasing tendency of the gastric lesion. In acetic acid-induced gastric lesions, repeated oral administration of DA-6034 exhibited a U-shape activity in ulcer healing, with the maximum and minimum inhibition being observed at 30 and 10 mg/kg/day, respectively. DA-6034 also increased the mucus content in the gel layer as well as endogenous prostaglandin E(2) synthesis. These results suggest that DA-6034 prevents gastric mucosal injury, and these gastroprotective activities appear to be due to the increase in the gastric defensive systems.

Jaceosidin induces apoptosis in ras-transformed human breast epithelial cells through generation of reactive oxygen species

Extracts of Artemisia plants possess anti-inflammatory and antioxidative activities. Eupatilin (5,7-dihydroxy-3',4',6-tri-methoxy-flavone), a pharmacologically active flavone derived from Artemisia asiatica, was shown to inhibit phorbol ester-induced cyclooxygenase-2 expression and NF-kappaB activation in mouse skin, and also to induce cell cycle arrest in ras-transformed human mammary epithelial (MCF10A-ras) cells. In this article, we examined the ability of jaceosidin (4',5,7-trihydroxy-3',6-dimethoxyflavone) isolated from Artemisia argyi to inhibit the proliferation of MCF10A-ras cells. Jaceosidin reduced the viability of MCF10A-ras cells to a greater extent than eupatilin. Jaceosidin treatment resulted in increased intracellular accumulation of reactive oxygen species (ROS) in MCF10A-ras cells, which was blocked by the antioxidant N-acetylcysteine (NAC). NAC attenuated jaceosidin-induced cytotoxicity. To better assess the proapoptotic effects of jaceosidin, we analyzed the treated cells by the flow cytometry. MCF10A-ras cells treated with jaceosidin (100 microM) exhibited the increased proportion of hypodiploid or apoptotic cells (48.72% as composed to 7.78% in control cells). Jaceosidin treatment also increased the ratio of proapoptotic Bax to the antiapoptotic Bcl-2 and induced the cleavage of caspase-3 and poly(ADP-ribose)polymerase (PARP). Moreover, jaceosidin elevated the expression of p53 and p21, while the compound inhibited the activation of ERK1/2 that is an important component of cell survival signaling.

DA-9601, a standardized extract of Artemisia asiatica, blocks TNF-α-induced IL-8 and CCL20 production by inhibiting p38 kinase and NF-κB pathways in human gastric epithelial cells

AIM: To investigate whether, or how, DA-9601, which is a new gastroprotective agent, inhibits TNF-α-induced inflammatory signals in gastric epithelial AGS cells.

METHODS: Cell viability was determined by MTT assay. IL-8 and CCL20 promoter activities were determined by a luciferease reporter gene assay. NF-κB-dependent transcriptional activity was determined by I-κBα degradation, NF-κB p65 nuclear translocation and a luciferase activity assay. IL-8 and CCL20 gene expression and protein secretion were determined by RT-PCR and an enzyme-linked immunosorbent assay (ELISA). Total and phosphorylated forms of mitogen-activated protein kinases (MAPKs) were determined by Western blot.

RESULTS: Treatment of AGS cells with DA-9601 reduced TNF-α-induced IL-8 and CCL20 promoter activities, as well as their gene expression and protein release. TNF-α also induced NF-κB-dependent transcriptional activity in AGS cells. In contrast, in cells treated with DA-9601, TNF-α-induced NF-κB activity was significantly blocked. Although all three MAP kinase family members were phosphorylated in response to TNF-α, a selective inhibitor of p38 kinase SB203580 only could inhibit both NF-κB-dependent transcriptional activity and IL-8 and CCL20 production, suggesting a potential link between p38 kinase and NF-κB-dependent pathways in AGS cells. Interestingly, DA-9601 also selectively inhibited p38 kinase phosphorylation induced by TNF-α.

CONCLUSION: DA-9601 blocked TNF-α-mediated inflammatory signals by potentially modulating the p38 kinase pathway and/or a signal leading to NF-κB-dependent pathways in gastric epithelial cells.

The fractionated Toona sinensis leaf extract induces apoptosis of human ovarian cancer cells and inhibits tumor growth in a murine xenograft model

OBJECTIVE

Aqueous extract from the leaves of Toona sinensis Roem. has been shown to have an anti-proliferative effect on human lung cancer cells. In this study, we analyzed the anti-cancer activity/effect of different extraction fractions of the extract from T. sinensis leaves on ovarian cancer cells.

METHODS

Cell viability was determined by XTT cell proliferation assay and cell survival assay. Apoptotic effect was detected by morphological analysis and immunoblotting. Cell cycle effect was evaluated by flow cytometry analysis and immunoblotting. In vivo therapeutic effect was evaluated by the subcutaneous inoculation of SKOV3 cells in nude mice (Foxnlnu/Foxnlnu) model.

RESULTS

TSL2 of T. sinensis was more cytotoxic than other fractions and exhibited selectivity for ovarian cancer cell lines. TSL2 arrested SKOV3 ovarian cancer cells at the G2/M phase and induced cancer cells go through apoptotic pathway. Ex vivo xenograft study of nude mice showed that intraperitoneal injection of TSL2 was able to suppress the proliferation of ovarian cancer cells without significant nephrotoxicity, liver toxicity, or bone marrow suppression.

Simultaneous determination of bioactive flavone derivatives in Chinese herb extraction by capillary electrophoresis used different electrolyte systems--borate and ionic liquids

In this paper, novel capillary electrophoresis (CE) methods, which used ionic liquids (1-ethyl-3-methylimidazoium tetrafluoroborate, 1-butyl-3-methylimidazoium tetrafluoroborate), were established to separate and determine some bioactive flavone derivatives in Chinese herb Seriphidium santolinum (Schrenk) Poljak. In order to investigate the traits of ionic liquids in CE, borate was also used as electrolyte to compare with. And the excellence of CE, which used ionic liquids as main running electrolyte and beta-cyclodextrin (beta-CD) as modifier, was illuminated as well. As a result of the study, the difference of ionic liquids and borate in CE was discussed and the advantage of CE, which used ionic liquids as electrolytes for separation, was shown. The analysis was obtained within short time (5-6 min). From the result, it was found that the system, which used ionic liquids, was robust because the joule heating was small. The method of CE, which used ionic liquids, has lower detection limits (0.137-0.642 microg/mL) than that of borate (0.762-1.036 microg/mL). And the CE, which used ionic liquids method, has lower limit of linear range (1.100-2.656 microg/mL), while that of CE, which used borate method, was 2.188-5.313 microg/mL.

Selective cytotoxicity of squamocin on T24 bladder cancer cells at the S-phase via a Bax-, Bad-, and caspase-3-related pathways

Annonaceous acetogenins are a group of potential anti-neoplastic agents isolated from Annonaceae plants. We purified squamocin, a cytotoxic bis-tetrahydrofuran acetogenin, from the seeds of Annona reticulata and analyzed its biologic effects on cancer cells. We showed that squamocin was cytotoxic to all the cancer lines tested. Furthermore, squamocin arrested T24 bladder cancer cells at the G1 phase and caused a selective cytotoxicity on S-phase-enriched T24 cells. It induced the expression of Bax and Bad pro-apoptotic genes, enhanced caspase-3 activity, cleaved the functional protein of PARP and caused cell apoptosis. These results suggest that squamocin is a potentially promising anticancer compound.

Eupatilin blocks mediator release via tyrosine kinase inhibition in activated guinea pig lung mast cells

Eupatilin, an extract from Artemisia asiatica Nakai, is known to exert anti-gastric ulcer, anticancer, and anti-inflammatory effects. The aim of this study was to elucidate whether eupatilin has antiallergic reactions in activated guinea pig lung mast cells compared to apigenin and genistein. Mast cells were purified from guinea pig lung tissues by using enzyme digestion and rough and discontinuous density Percoll gradient. The purified mast cells were sensitized with immunoglobulin (Ig) G(1) (anti-OVA antibody) and challenged with ovalbumin (OVA). Histamine was assayed using an automated fluorometric analyzer, leukotrienes by radioimmunoassay, and tyrosine phosphorylation by immunoblotting. Intracellular Ca(2+) was analyzed by confocal laser scanning microscopy, protein kinase C (PKC) activity using protein phosphorylated with [gamma-(32)P]ATP, and phopholipase D activity (PLD) and phosphatidic acid by using labeled phosphatidyl alcohol. Eupatilin, apigenin, or genistein reduced histamine release and leukotriene synthesis in a does-dependent manner. Eupatilin inhibited mediators to a greater extent than apigenin or genistein. Eupatilin, apigenin, and genistein initially blocked phosphorylation of Syk tyrosine and Ca(2+) influx, PLD activity, phosphatidic acid, and Ca(2+)-dependent PKC alpha/betaII activities during mast cell activation in a dose-dependent manner. Our data suggest that eupatilin initially inhibits Syk kinase, and then blocks downstream multisignal pathways and Ca(2+) influx during mast cell activation triggered by a specific antigen-antibody reaction. Thus, eupatilin may have use clinically as a treatment for inflammatory disorders associated with allergic diseases including asthma.

Cell death induced by ent-11α-hydroxy-15-oxo-kaur-16-en-19-oic-acid in anaplastic thyroid carcinoma cells is via a mitochondrial-mediated pathway

The chemical compound ent-11alpha-hydroxy-15-oxo-kaur-16-en-19-oic-acid (5F), isolated from the Chinese herbal medicine plant Pteris semipinnata L, has been known to exert antitumor activity. However, the molecular mechanism of the action is not understood. In this study we demonstrated that apoptotic cell death induced by 5F in FRO cells was concentration- and time-dependent. The rapid increase in intracellular reactive oxygen species (ROS) levels was involved in the mechanism of cell death. c-Jun N-terminal kinase (JNK) activation and G2 block were related to cell death induced by 5F. Extracellular signal-related kinase (ERK) and p38 were also activated, but as survival signals in response to 5F treatment to counteract the induction of cell death. In the process of the induction of apoptotic cell death, Bax translocated into mitochondria, a reduction in Delta psi(m) was observed and a release of cytochrome c and apoptosis inducing factor (AIF) from mitochondria into the cytosol occurred, indicating that cell death induced by 5F was through a mitochondrial-mediated pathway.

Novel nonaqueous capillary electrophoresis separation and determination of bioactive flavone derivatives in Chinese herbs

Nonaqueous CE (NACE) coupled to UV detection is described for the separation and determination of bioactive flavone derivatives in Chinese herbs extraction. After optimization of electrophoresis parameters, including the electrolyte nature and the organic solvent composition, a reliable separation of the analytes in an ACN/methanol (60:40, v/v) mixture containing 80 mM Tris and 10 mM sodium cholate was performed. The detection was performed at 254 nm. Method performances, including migration time and peak area reproducibility, linearity, sensitivity, and accuracy, were evaluated. The method was applied to determine bioactive flavone derivatives in seven Chinese herbs.

Cell death induced byPteris semipinnataL. is associated with p53 and oxidant stress in gastric cancer cells

In this study, we demonstrated that Ent-11alpha-hydroxy-15-oxo-kaur-16-en-19-oic-acid (5F) had stronger cytotoxicity against MKN-45, a gastric cancer cell line bearing wild-type p53 than MKN-28, another gastric cancer cell line containing missense mutation in p53. The rapid increase of ROS level was involved in the mechanism of cytotoxicity. Classical features of apoptosis induced by 5F were observed in MKN-45 cells only or more significant in MKN-45 cells than MKN-28 cells. Translocation of Bax from cytosol to mitochondria, reduction of delta psi m and DNA fragmentation were induced by 5F in the p53-dependent manner. We conclude that the expression of Bax and its downstream molecules requires the presentation of a wild-type p53 in the cells treated by 5F.

Induction of apoptosis and necrosis in A549 cells by the cis-Pt(II) complex of 3-aminoflavone in comparison with cis-DDP

Non-small cell lung cancer (NSCLC) includes a group of tumors that respond poorly to drugs. cis-Diamminedichloroplatinum(II) (cis-DDP) toxicity still remains problematic, and not completely solved by the improvement of supportive care. Therefore, the cis-Pt(II) complex of 3-aminoflavone was selected from cis-DDP analogues with a more favourable toxic profile towards normal cells and at least similar or better anti-tumor activity in comparison with cis-DDP. The aim of this research is to compare the ability of the cis-Pt(II) complex of 3-aminoflavone and cis-DDP to induce apoptosis and necrosis in the human non-small cancer cell line A549. Trypan blue dye exclusion, fluorochrome staining (acridine orange/ethidium bromide double staining), MTT and TUNEL (TdT-mediated dUTP Nick-End Labeling) assays were used. The results obtained show that the cis-Pt(II) complex of 3-aminoflavone is more active in inducing apoptosis and necrosis and in decreasing viability in A549 cells than cis-DDP, which suggests that it could be a potential chemotherapeutic drug.

Eupatilin, a pharmacologically active flavone derived from Artemisia plants, induces cell cycle arrest in ras-transformed human mammary epithelial cells

Extracts of Artemisia asiatica Nakai (Asteraceae) possess anti-inflammatory and anti-oxidative activities. Eupatilin (5,7-dihydroxy-3',4',6-trimethoxyflavone), one of the pharmacologically active ingredients derived from A. asiatica, was shown to induce apoptosis in human promyelocytic leukemia (HL-60) cells [Mutat Res 496 (2001) 191]. In the present study, we examined the cytostatic effects of eupatilin in H-ras-transformed human breast epithelial (MCF10A-ras) cells. Eupatilin inhibited the growth of MCF10A-ras cells in a concentration-dependent and time-related manner. To explore whether the anti-proliferative effects of eupatilin could be mediated through modulation of the cell cycle in MCF10A-ras, DNA contents were analyzed by the flow cytometry. Eupatilin inhibited the expression of cyclin D1, cyclin B1, Cdk2 and Cdc2 that are key regulators of the cell cycle. In addition, eupatilin treatment led to elevated expression of p53 and p27Kip1 that act as Cdk inhibitors. It has been known that the Ras-signaling pathway plays integral roles in the induction of cyclin D1. Eupatilin inhibited the activation of ERK1/2 as well as expression of Raf-1 and Ras in MCF10A-ras cells. Thus, the inhibitory effect of eupatilin on cyclin D1 expression appears to be mediated by targeting the Raf/MEK/ERK signaling cascades. Eupatilin did not change activation of Akt, an important component of cell-survival pathways. In conclusion, the anti-proliferative effect of eupatilin in MCF10A-ras cells is associated with its blockade of cell cycle progression which appears to be attributable in part to inhibition of ERK1/2 activation.

Methylene Chloride Fraction of Spatholobi Caulis Induces Apoptosis via Caspase Dependent Pathway in U937 Cells

Spatholobi Caulis has been used in Oriental medicine to treat cancer and blood stasis. In this study, the methylene chloride fraction of Spatholobi Caulis (MCSC) was examined to determine if it possesses anti-cancer activity via its apoptosis-inducing activity. MCSC exhibited a strong cytotoxic effect against human monocyte leukemia U937 cells (IC(50)=15.1 microg/ml). A TUNEL assay showed that the MCSC caused a characteristic ladder pattern of discontinuous DNA fragments and apoptotic bodies. Flow cytometric analysis confirmed that MCSC significantly increases the number of apoptotic cells stained by annexin V(+)/PI(-) cells. Western blotting revealed that MCSC activated caspase-3 expression and cleaved poly (ADP-ribose) polymerase (PARP) in a concentration-dependent manner. An enzyme-linked immunosorbent assay (ELISA) demonstrated that MCSC significantly activated the caspase-3 activity compared with the untreated control by. Taken together, these results suggest that MCSC can induce apoptosis in U937cells via the caspase dependent pathway.

Induction of apoptosis by takrisodokyeum through generation of hydrogen peroxide and activation of caspase-3 in HL-60 cells

Takrisodokyeum (TRSDY), a Chinese herbal medicine, has been known to exert anti-tumoral activity in Korea. However, its molecular mechanism of action is not understood. In this study, we found that TRSDY induced apoptosis in HL-60 cells as evidenced by both a characteristic ladder pattern of discontinuous DNA fragments and an increase of annexin V+/PI- stained cell population. Our data demonstrated that TRSDY-induced apoptotic cell death was accompanied by activation of caspase-3 and cleavages of its substrates, poly(ADP-ribose) polymerase (PARP) and RhoGDP dissociation inhibitor (RhoGDI-2; also called D4-GDI) in a time- and concentration-dependent manner. Caspase-3 inhibitor, but not caspase-1 inhibitor, prevented TRSDY-induced apoptosis. Furthermore, treatment with TRSDY increased the production of intracellular hydrogen peroxide and pretreatment of cells with anti-oxidants conferred complete protection against hydrogen peroxide generation and subsequent caspase-3 activation. Taken together, these results suggest that TRSDY induces hydrogen peroxide generation, which, in turn, causes activation of caspase-3, degradation of PARP and D4-GDI, and eventually leads to apoptotic cell death.

Annonacin, a mono-tetrahydrofuran acetogenin, arrests cancer cells at the G1 phase and causes cytotoxicity in a Bax- and caspase-3-related pathway

Annonaceous acetogenins are a group of potential anti-neoplastic agents isolated from Annonaceae plants. In this study, we purified annonacin, a cytotoxic mono-tetrahydrofuran acetogenin, from the seeds of Annona reticulata and analyzed its biological effects. Herein, we have shown that annonacin caused significant cell death in various cancer cell lines. T24 bladder cancer cells at the S phase were more vulnerable to the cytotoxicity of annonacin. Furthermore, annonacin activated p21 in a p53-independent manner and arrested T24 cells at the G1 phase. It also induced Bax expression, enhanced caspase-3 activity, and caused apoptotic cell death in T24 cells. In summary, these results suggest that annonacin is potentially a promising anti-cancer compound.

Discovery of cancer preventive agents from natural products: from plants to prevention

Cancer chemoprevention has traditionally been defined as a dietary or therapeutic approach for the prevention, delay, or reversal of carcinogenesis. We currently expand this definition to include nontoxic applications for patients with established disease. In this context, efficacy can be achieved by selectively altering cell-cycle progression. In the quest for new cancer chemopreventive agents, we have focused on the isolation of natural products as lead molecules, followed by synthetic modification to improve activity. Using biologic response as a guide for fractionation, over 200 active compounds have been identified. Some of the most interesting include brassinin and 4'-bromoflavone as inducers of quinone reductase, deguelin as an inhibitor of ornithine decarboxylase, resveratrol as an inhibitor of cyclooxygenase, and brusatol as an inducer of cellular differentiation. These agents have demonstrated effectiveness in experimental models of carcinogenesis. Further development of these agents as chemopreventive drugs may proceed through the normal regulatory process (eg, 4'-bromoflavone). Alternatively, some natural products may be administered as dietary supplements (eg, resveratrol). In either case, chemoprevention offers great hope in reducing the morbidity and mortality associated with cancer.

In Vitro Immunomodulatory Effects of Herbal Products

Immunosuppressive drugs have been developed from natural products such as soil and fungi, which are also the sources of some commonly used herbal products. However, the effect of herbal products on immune response has not been investigated. Because these products can affect the host immune system they can induce either rejection or tolerance after a transplant procedure. To investigate the effects of ten commonly used herbal products on transplant-related immune function we performed in vitro lymphocyte proliferation tests using phytohemagglutinin, mixed lymphocyte culture (MLC) assay, and interleukin (IL)-2 and IL-10 production from MLC. Dong quai, ginseng, and milk thistle had nonspecific immunostimulatory effects on lymphocyte proliferation, whereas ginger and green tea had immunosuppressive effects. Dong quai and milk thistle increased alloresponsiveness in MLC, whereas ginger and tea decreased these responses. The immunostimulatory effects of dong quai and milk thistle were consistently seen in both cell-mediated immune response and nonspecific lymphoproliferation, whereas that of ginseng was not The immunosuppressive effect of green tea and ginger were mediated through a decrease in IL-2 production, but the immunostimulatory effects of dong quai and milk thistle were not. We conclude that green tea, dong quai, ginseng, milk thistle, and ginger have effects on in vitro immune assays that may be relevant in transplantation in humans.

Inhibitory effects of the standardized extract (DA-9601) of Artemisia asiatica Nakai on phorbol ester-induced ornithine decarboxylase activity, papilloma formation, cyclooxygenase-2 expression, inducible nitric oxide synthase expression and nuclear transcription factor kappa B activation in mouse skin

Artemisia asiatica Nakai has been used in traditional Asian medicine for the treatment of inflammatory and other disorders. Previous studies have revealed that the formulated ethanol extract (DA-9601) of A. asiatica has pronounced antioxidative and antiinflammatory activities and exhibits cytoprotective effects against experimentally induced gastrointestinal, hepatic and pancreatic damage. In the present study, we assessed the inhibitory effect of DA-9601 on tumor promotion, which is closely linked to inflammatory tissue damage. As an initial approach to evaluating the possible antitumor-promoting potential of DA-9601, its effects on TPA-induced ear edema were examined in female ICR mice. Pretreatment of the inner surface of the mouse ear with DA-9601 30 min prior to topical application of TPA inhibited ear edema at 5 hr. TPA-stimulated expression of epidermal COX-2 and iNOS was also mitigated by topical application of the same extract. Moreover, DA-9601 abrogated the TPA-mediated activation of NF-kappa B/Rel and AP-1 in mouse epidermis. Suppression of epidermal NF-kappa B by DA-9601 appeared to be mediated in part through inhibition of I kappa B alpha degradation, thereby blocking the nuclear translocation of p65, the functional subunit of NF-kappa B. DA-9601 also significantly suppressed TPA-induced ODC activity and papilloma formation in mouse skin. Taken together, these findings suggest that DA-9601 derived from A. asiatica possesses potential chemopreventive activities.