A new benzofuran from Artemisia halodendron Turcz. ex Bess.

A new benzofuran, methyl (2S,2″S,3'E)-[2-(1″-acetoxypropan-2-yl)-2,3-dihydrobenzofuran-5-yl]acrylate (1), and 13 known compounds (2-14) were isolated from an ethanol extract of Artemisia halodendron Turcz. ex Bess. The chemical structures of these compounds were determined by 1D and 2D NMR (1H-1H COSY, HMBC, HMQC and NOESY) and HR-ESI-MS spectra, and results were compared with data from the literature. The effects of compounds 1-14 were measured on NF-κB activation, with compounds 2 and 3 exhibiting inhibitory activities against TNF-α-induced NF-κB reporter gene expression in HeLa cells from 10 to 100 µM.

Carnosine Inhibits the Proliferation of Human Cervical Gland Carcinoma Cells Through Inhibiting Both Mitochondrial Bioenergetics and Glycolysis Pathways and Retarding Cell Cycle Progression.

Carnosine has been demonstrated to play an antitumorigenic role in certain types of cancer. However, its underlying mechanism is unclear. In this study, the roles of carnosine in cell proliferation and its underlying mechanism were investigated in the cultured human cervical gland carcinoma cells HeLa and cervical squamous carcinoma cells SiHa. The results showed that carnosine exerted a significant inhibitory effect on the proliferation of HeLa cells, whereas its inhibitory action on the proliferation of SiHa cells was much weaker. Carnosine decreased the ATP content through inhibiting both mitochondrial respiration and glycolysis pathways in cultured HeLa cells but not SiHa cells. Carnosine reduced the activities of isocitrate dehydrogenase and malate dehydrogenase in TCA (tricarboxylic acid) cycle and the activities of mitochondrial electron transport chain complex I, II, III, and IV in HeLa cells but not SiHa cells. Carnosine also decreased the mRNA and protein expression levels of ClpP, which plays a key role in maintaining the mitochondrial function in HeLa cells. In addition, carnosine induced G1 arrest by inhibiting the G1-S phase transition in both HeLa and SiHa cells. Taken together, these findings suggest that carnosine has a strong inhibitory action on the proliferation of human cervical gland carcinoma cells rather than cervical squamous carcinoma cells. Mitochondrial bioenergetics and glycolysis pathways and cell cycle may be involved in the carnosine action on the cell proliferation in cultured human cervical gland carcinoma cells HeLa.

Seco-ursane-type Triterpenoids from Salvia urmiensis with Apoptosis-inducing Activity.

Fractionation of an acetone extract of the aerial parts of Salvia urmiensis led to the isolation of a new (1) and a known (2) E-seco-ursane-type triterpenoid, together with four other known compounds. Their structures were established by 1D and 2D nuclear magnetic resonance as well as high-resolution electrospray ionization mass spectrometry. The effect of compounds 1 and 2 on cell viability of HeLa and HepG2 cells was investigated with the MTT assay. We also report the mechanism of action of compound 2 as a potential anticancer agent in HeLa cells. Bcl-2, Bax, and caspases signaling pathway expression in HeLa cells was analyzed. HeLa cells treated with compound 2 were assayed for the cleavage of poly-(ADP-ribose)-polymerase and DNA fragmentation resulting in nuclear shrinkage. Taken together, these results suggest that treatment of HeLa cells with compound 2 can induce apoptosis by regulating Bcl-2 family members and by suppressing caspase cascade activation.

Curcumin targeting the thioredoxin system elevates oxidative stress in HeLa cells.

The thioredoxin system, composed of thioredoxin reductase (TrxR), thioredoxin (Trx), and NADPH, is ubiquitous in all cells and involved in many redox-dependent signaling pathways. Curcumin, a naturally occurring pigment that gives a specific yellow color in curry food, is consumed in normal diet up to 100mg per day. This molecule has also been used in traditional medicine for the treatment of a variety of diseases. Curcumin has numerous biological functions, and many of these functions are related to induction of oxidative stress. However, how curcumin elicits oxidative stress in cells is unclear. Our previous work has demonstrated the way by which curcumin interacts with recombinant TrxR1 and alters the antioxidant enzyme into a reactive oxygen species (ROS) generator in vitro. Herein we reported that curcumin can target the cytosolic/nuclear thioredoxin system to eventually elevate oxidative stress in HeLa cells. Curcumin-modified TrxR1 dose-dependently and quantitatively transfers electrons from NADPH to oxygen with the production of ROS. Also, curcumin can drastically down-regulate Trx1 protein level as well as its enzyme activity in HeLa cells, which in turn remarkably decreases intracellular free thiols, shifting the intracellular redox balance to a more oxidative state, and subsequently induces DNA oxidative damage. Furthermore, curcumin-pretreated HeLa cells are more sensitive to oxidative stress. Knockdown of TrxR1 sensitizes HeLa cells to curcumin cytotoxicity, highlighting the physiological significance of targeting TrxR1 by curcumin. Taken together, our data disclose a previously unrecognized prooxidant mechanism of curcumin in cells, and provide a deep insight in understanding how curcumin works in vivo.

Effects of 20-hydroxyecdysone, Leuzea carthamoides extracts, dexamethasone and their combinations on the NF-κB activation in HeLa cells.

OBJECTIVES: The plant steroid 20-hydroxyecdysterone (20E) and 20E-containing extracts from Leuzea carthamoides (Willd.) DC are sold with claims of anabolic and immunomodulatory effects. Yet their effect on the activation of nuclear factor kappa B (NF-κB), a key player in immune response and cell fate, and their influence on the NF-κB-inhibiting activity of steroidal anti-inflammatory drugs is still unknown. METHODS: The ability of 20E, Leuzea extracts and selected steroidal/non-steroidal anti-inflammatory drugs to influence the activation of NF-κB was explored using, as the experimental model, human cervical cancer HeLa-IL-6 cells stably transfected with an IL-6-bound reporter gene. Effects on cell viability and proliferation were monitored (MTT assay). HPLC-DAD was used to establish links between chemical patterns of Leuzea extracts and their bioactivities. KEY FINDINGS: 20E inhibited NF-κB activation (IC50 31.8 µm) but was less active than other plant metabolites (xanthohumol 3.8 µm, withaferin A 1.4 µm). Leuzea extracts with high content in 20E had a fair activating effect, but in contrast, some extracts with low 20E content significantly inhibited NF-κB activation at IC50s ranging from 3.5 to 6.2 µg/ml. Combination tests confirmed that 20E does not explain the NF-κB modulation achieved by Leuzea extracts. The extracts but not 20E itself showed a significant modulation of the NF-κB inhibitory effect of dexamethasone. CONCLUSIONS: 20E is unlikely a major player in the NF-κB inhibitory effects displayed by some Leuzea extracts in vitro. If confirmed in vivo, caution should prevail towards marketed Leuzea extracts that are non-standardised or standardised on 20E only, since different starting materials and extracts may even cause opposite effects. More importantly, our results indicate the interaction potential of Leuzea with steroidal anti-inflammatory drugs.

Protein tyrosine kinase pathway-derived ROS/NO productions contribute to G2/M cell cycle arrest in evodiamine-treated human cervix carcinoma HeLa cells.

A previous study indicated that reactive oxygen species (ROS) and nitric oxide (NO) played pivotal roles in mediating cytotoxicity of evodiamine in human cervix carcinoma HeLa cells. This study suggested that G2/M cell cycle arrest was triggered by ROS/NO productions with regulations of p53, p21, cell division cycle 25C (Cdc25C), Cdc2 and cyclin B1, which were able to be prevented by protein tyrosine kinase (PTK) activity inhibitor genistein or JNK inhibitor SP600125. The decreased JNK phosphorylation by addition of Ras or Raf inhibitor, as well as the increased cell viability by addition of insulin-like growth factor-1 receptor (IGF-1R), Ras, Raf or c-Jun N-terminal kinase (JNK) inhibitor, further demonstrated that the Ras-Raf-JNK pathway was responsible for this PTK-mediated signalling. These observations provide a distinct look at PTK pathway for its suppressive effect on G2/M transition by inductions of ROS/NO generations.

Potentiation of etoposide-induced apoptosis in HeLa cells by co-treatment with KG-135, a quality-controlled standardized ginsenoside formulation.

Our previous studies demonstrated that KG-135, a quality-controlled red ginseng-specific formulation containing approximately equal amounts of three major ginsenosides (Rk1, Rg3 and Rg5), down-regulated G1 cyclin-dependent kinase in HeLa cells. In the present work, we have found that KG-135 potentates cytotoxicity of etoposide by modulating apoptotic signaling. Co-treatment of etoposide and KG-135 markedly elevated the expression and phosphorylation at the serine 15 residue of p53 as well as the cellular levels of Bax and p21(Waf1/Cip1). The increased accumulation and phosphorylation of p53 (Ser15) were attenuated by treatment of cells with wortmannin, a pan-phosphatidylinositol-3 kinase inhibitor. Moreover, co-treatment of etoposide and KG-135 enhanced mitochondrial localization of Bax. Our results indicate that etoposide-induced apoptosis in HeLa cells can be potentiated in the presence of KG-135 through a mechanism that involves the stabilization of p53 and the stimulation of Bax- and p21-mediated apoptotic signaling pathways. These findings suggest that KG-135 represents a useful candidate adjuvant for the treatment of cancers that could potentially minimize the adverse effects of current clinical chemotherapeutics.

Phenolic constituents of Amorpha fruticosa that inhibit NF-kappaB activation and related gene expression.

NF-kappaB is known to play a crucial role in the regulation of genes controlling the immune system, apoptosis, tumor cell growth, and tissue differentiation. Bioassay-guided fractionation of the n-hexane-soluble fraction of a methanol extract of Amorpha fruticosa afforded four new compounds, 5, 7, 8, and 9, and eight known compounds. Their structures were elucidated by spectroscopic methods. All compounds inhibited NF-kappaB activity, and tephrosin (1), 11-hydroxytephrosin (2), and deguelin (3) were the most active, with IC50 values of 0.11, 0.19, and 0.22 microM, respectively, in TNF-alpha-stimulated HeLa cell-based reporter gene assays. Further investigations showed that compounds 1, 5, and 6 blocked NF-kappaB/DNA binding activity and suppressed the expression of NF-kappaB target genes.

NF-kappaB inhibitory activity of compounds isolated from Cantharellus cibarius.

The inhibitory activities of the extracts of Cantharellus cibarius and isolated compounds were investigated in an enzyme-based ELISA NF-kappaB assay. Of the tested compounds, ergosterol, ergosterol peroxide and cerevisterol were noted to have the most potent inhibition of NF-kappaB activation. The ability of the active metabolites to inhibit the NF-kappaB translocation from the cytoplasm to the nucleus was assessed using a cell-based NF-kappaB assay. The isolated compounds were elucidated through the analysis of various spectroscopic methods.

Large-scale analysis of glucocorticoid target genes in rat hypothalamus.

Insufficient glucocorticoid (GC) signaling is frequently observed in major depressive disorder (MDD). Since emotional and behavioral symptoms are often accompanied by disturbances in hypothalamic systems, GC insufficiency in this region is regarded as important in the pathogenesis of MDD. In this study, 22 early GC-responsive genes comprising 15 up-regulated and 7 down-regulated genes in rat hypothalamus were identified as being regulated at least two-fold by dexamethasone using microarray with 22 599 unique transcripts. Among these 22 genes, five of which are novel GC-responsive genes, the expression patterns of sgk, bcl6, pdk4, and plekhf1 were examined in vitro in detail, and GC-responsive regions were identified only within the promoter of sgk. This suggests that glucocorticoid response element-independent pathways also play a critical role in early GC-response in hypothalamus. Considering that a number of these GC-responsive genes are candidate neuronal regulators, this gene list should be useful in clarifying the relationship between GC insufficiency and the pathogenesis of MDD.

Image-based multivariate profiling of drug responses from single cells.

Quantitative analytical approaches for discovering new compound mechanisms are required for summarizing high-throughput, image-based drug screening data. Here we present a multivariate method for classifying untreated and treated human cancer cells based on approximately 300 single-cell phenotypic measurements. This classification provides a score, measuring the magnitude of the drug effect, and a vector, indicating the simultaneous phenotypic changes induced by the drug. These two quantities were used to characterize compound activities and identify dose-dependent multiphasic responses. A systematic survey of profiles extracted from a 100-compound compendium of image data revealed that only 10-15% of the original features were required to detect a compound effect. We report the most informative image features for each compound and fluorescence marker set using a method that will be useful for determining minimal collections of readouts for drug screens. Our approach provides human-interpretable profiles and automatic determination of on- and off-target effects.

Evaluation of estrogenic/antiestrogenic activity of Onobrychis ebenoides extract - interaction with estrogen receptor subtypes ERalpha and ERbeta.

A protective effect of plant extract from Onobrychis ebenoides on ovariectomy-induced bone loss in rats has been shown. To investigate the molecular mechanisms that underly the beneficial effect of O. ebenoides (Onb) on bone loss, we studied its potential to activate ER subtypes (ERalpha and ERbeta) on transiently transfected HeLa cells with HO-hERalpha or pSG5-hERbeta and 3xERE-TATA-Luc expression vectors. Its impact to stimulate differentiation and mineralization of osteoblasts (KS483 cell line) by Alizarin Red-S staining was also examined. Furthermore we sought to induce for its potential the IGFBP3, a known estrogen-dependent marker in MCF7 breast cancer cells. 17beta-Estradiol and the pure antiestrogen ICI182780 were included to serve as control samples of the estrogenic and antiestrogenic activity respectively. Our data revealed: (1) Onb extract displayed a significant estrogenic activity on both ERalpha and ERbeta subtypes. (2) It exhibited direct action on osteoblasts by inducing mineralization. (3) It showed estrogenic activity in MCF7 cells. These findings suggest that the beneficial effect of Onb extract on bone loss is mediated through an estrogen-like action via activation of ERalpha-ERE and ERbeta-ERE pathways and via direct action on the mineralization process of osteoblasts.

[Inhibitory effects of Scutellaria barbatae D. Don on tumor angiogenesis and its mechanism].

BACKGROUND & OBJECTIVE: Various chemically synthetic anti-angiogenesis agents have serious side effects. The traditional Chinese medicine has attracted considerable attention because of its low toxicity. This study was to explore the inhibitory effects of Scutellaria barbatae D. Don, a kind of traditional Chinese medicinal anti-cancer herb, on tumor angiogenesis, and investigate its mechanism. METHODS: Matrigel plug and human umbilical vascular endothelial cells (HUVECs) were used to construct in vivo and in vitro models of angiogenesis to assess the effect of Scutellaria barbatae D. Don on angiogenesis. After cultured with Scutellaria barbatae D. Don, the migration of endothelial cells was examined by Transwell chamber; the expression of vascular endothelial growth factor (VEGF) in HeLa cells was detected by enzyme-linked immunosorbent assay (ELISA). RESULTS: Scutellaria barbatae D. Don significantly inhibited angiogenesis in Matrigel; the tube formation number was significantly lower in 20% and 40% medicated serum groups containing Scutellaria barbatae D. Don than in 20% and 40% drug-free serum groups (5.6+/-1.1 vs. 9.8+/-1.3, P=0.001; 1.0+/-0.7 vs. 13.4+/-1.1, P<0.001). Migrated endothelial cells was significantly fewer in 20% and 40% medicated serum groups containing Scutellaria barbatae D. Don than in 20% and 40% drug-free serum groups (19.75+/-2.63 vs. 24.25+/-2.06, P=0.038; 14.00+/-2.58 vs. 26.5+/-4.65, P=0.006). When treated for 24 h and 48 h, the expression of VEGF in HeLa cells was significantly lower in 40% medicated serum group containing Scutellaria barbatae D. Don than in 40% drug-free serum group (138.67+/-9.50 vs. 195.82+/-2.43, P=0.006; 93.84+/-41.11 vs. 193.68+/-18.37, P=0.036). CONCLUSION: Scutellaria barbatae D. Don could efficiently inhibit angiogenesis in tumor tissue which might relate with inhibition of endothelial cell migration and down-regulation of VEGF in tumor cells.

A novel mechanism of action of the fumagillin analog, TNP-470, in the B16F10 murine melanoma cell line.

TNP-470, a semisynthetic derivative of fumagillin, is an acknowledged angiogenesis inhibitor, presently undergoing clinical trials. It exerts an anti-proliferative effect directed against endothelial cells. This effect is known to be based on cell cycle inhibition effected by the p53/p21 pathway. We observed short-term toxicity of TNP-470 in the B16F10 murine melanoma cell line in vitro and investigated the mechanism of action. Cell death occurred as soon as 2 h after the addition of TNP-470, without typical apoptotic features. The toxic effect could be modulated and it depended on the type of culture medium or supplementation with anti-oxidants. Addition of N-acetylcysteine protected B16F10 cells from TNP-470-induced death and inhibited an increase in the generation of reactive oxygen species (ROS), which are detected by the 2',7'-dichlorodihydrofluorescein diacetate probe. We conclude that TNP-470 can induce intracellular generation of ROS, which act toxically inside B16F10 cells. One may suggest that this novel activity of TNP-470 might be beneficial in some cases, but it could also be responsible for some undesirable side-effects. The possibility of its modulation gives a prospect for controlling the action of this potential drug and probably its derivatives.

Multidrug-resistant hela cells overexpressing MRP1 exhibit sensitivity to cell killing by hyperthermia: interactions with etoposide.

PURPOSE: Multidrug resistance (MDR) remains one of the primary obstacles in cancer chemotherapy and often involves overexpression of drug efflux transporters such as P-glycoprotein and multidrug resistance protein 1 (MRP1). Regional hyperthermia is undergoing clinical investigation in combination with chemotherapy or radiotherapy. This study evaluates whether hyperthermia can reverse MDR mediated by MRP1 in human cervical adenocarcinoma (HeLa) cells. METHODS AND MATERIALS: Cytotoxicity of hyperthermia and/or etoposide was evaluated using sulforhodamine-B in HeLa cells overexpressing MRP1 and their drug-sensitive counterparts. Glutathione, glutathione peroxidase (GPx), and glutathione S-transferase (GST) were quantified by spectrophotometry. GST isoenzymes were quantified by immunodetection. Caspase activation was evaluated by fluorometry and chromatin condensation by fluorescence microscopy using Hoechst 33258. Necrosis was determined using propidium iodide. RESULTS: The major finding is that HeLa and HeLaMRP cells are both sensitive to cytotoxicity of hyperthermia (41-45 degrees C). Hyperthermia induced activation of caspase 3 and chromatin condensation. Although total levels of cell killing were similar, there was a switch from apoptotic to necrotic cell death in MDR cells. This could be explained by decreased glutathione and GPx in MDR cells. MDR cells also contained very low levels of GST and were resistant to etoposide-induced apoptosis. Hyperthermia caused a modest increase in etoposide-induced apoptosis in HeLa and HeLaMRP cells, which required appropriate heat-drug scheduling. CONCLUSIONS: Hyperthermia could be useful in eliminating MDR cells that overexpress MRP1.

Evodiamine induces tumor cell death through different pathways: apoptosis and necrosis.

AIM: To study the different death pathways in human cervical cancer HeLa and melanoma A375-S2 cells initiated by evodiamine. METHODS: Viability of evodiamine-induced HeLa and A375-S2 cells was measured by MTT assay. Apoptotic cells with condensed or fragmented nuclei were visualized by Hoechst 33258 staining. Nucleosomal DNA fragmentation was assayed by agarose gel electrophoresis. Proportion of cell death through apoptotic and necrotic pathways was determined by LDH activity-based cytotoxicity assays. Cell cycle distribution was observed by flow cytometry. RESULTS: Evodiamine induced HeLa and A375-S2 cell death dose- and time-dependently. Caspase-3 and -8 were activated in apoptosis induced by evodiamine 15 micromol/L. However, over 24-h incubation of A375-S2 cells, evodiamine 15 micromol/L initiated necrosis related to p38 and ERK (extracellular signal-regulated kinases) activities. Evodiamine-induced HeLa cell death was preceded by an accumulation of cells at the G2/M phase of the cell cycle, but there was no significant effect of evodiamine on A375-S2 cell cycle. CONCLUSION: Evodiamine induces caspase-3,8-dependent apoptosis in HeLa cells which is related to G2/M arrest of the cell cycle. On the other hand, in A375-S2 cells, evodiamine initiates caspase-3,8-mediated apoptosis at early stages and the induction of MAPK-mediated necrosis at later stages of cell culture.

In vitro anti-inflammatory activity of Phlebodium decumanum. Modulation of tumor necrosis factor and soluble TNF receptors.

The immunomodulatory activity of a standardized water soluble fraction of the fern Phlebodium decumanum (EXPLY-37) previously shown to have "in vivo" anti-inflammatory activity was analyzed "in vitro". This extract inhibited tumor necrosis factor (TNF) production by macrophages activated with lipopolysaccharide (LPS) or LPS plus interferon (IFN)-gamma. In contrast, nitric oxide (NO) and interleukin (IL)-1beta production were not affected in the same cultures, whereas IL-6 production was partially inhibited. More interestingly, EXPLY-37 increased the release of soluble TNF-receptor 2 (sTNFR2) and of IL-1R antagonist (IL-1Ra) but not of sTNFR1, by activated macrophages. EXPLY-37 had no effect on T lymphocyte activation, measured as proliferation as well as expression of early and late cell surface antigens CD69, CD25 (IL-2R-alpha) and CD71 (transferrin receptor) at the cell membrane. At the molecular level, EXPLY-37 did not inhibit the activation of the nuclear factor kappa B (NF-kappaB) transcription factor by TNF. In summary, EXPLY-37 has two anti-inflammatory activities "in vitro": it decreases TNF production and increases IL-1Ra and sTNFR2, which may be able to neutralize IL-1 and TNF activity, respectively.

mRNA instability in the nucleus due to a novel open reading frame element is a major determinant of the narrow tissue specificity of folate receptor alpha.

The folate receptor type alpha (FR-alpha) is a promising tumor marker and target. Here, we investigate the mechanistic basis for the tumor specificity and vast overexpression of FR-alpha. Among representative FR-alpha-positive (HeLa and JAR) and FR-alpha-negative (MG63, Caki1, and HT3) cell lines, the transcription rates of the endogenous FR-alpha gene, as well as the FR-alpha promoter activity, were relatively weak and comparable, but the FR-alpha transcript was abundant only in total RNA and nuclear RNA from the FR-alpha-positive cells. Rous sarcoma virus (RSV) promoter-driven expression of the FR-alpha gene was 7 to 30 times greater in the FR-alpha-positive than in FR-alpha-negative cells, both at the protein and mRNA levels, independently of intron sequences. Through the use of chimeric FR-alpha/FR-beta cDNAs, the above pattern of FR-alpha expression was attributed to a 60-bp sequence in the FR-alpha open reading frame. This sequence element, when placed in the 5' untranslated region of RSV promoter-luciferase, decreased the reporter expression approximately 7- to 20-fold in FR-alpha-negative cells (MG63, Caki1, HT3, BG1, and MCF7) relative to FR-alpha-positive cells (HeLa, JAR, and JEG3). Substitution of this FR-alpha element in FR-beta increased the in vivo degradation rate of the transcript in the nuclei of MG63 cells but not in the nuclei of HeLa cells or in the cytosol of MG63 or HeLa cells. The results reveal an efficient mechanism by which a novel sequence element causes differential transcript degradation in the nucleus to ensure narrow tissue specificity for a gene (e.g., that for FR-alpha) whose transcription is weak and relatively nonselective. FR-alpha exhibited constitutive mRNA and protein synthesis during the cell cycle and a slow protein turnover, presumably ensuring a high steady-state level of the receptor in cells that could override the nuclear mRNA instability determinant.

Relationships and distinctions in iron-regulatory networks responding to interrelated signals.

Specialized cDNA-based microarrays (IronChips) were developed to investigate complex physiological gene-regulatory patterns in iron metabolism. Approximately 115 human cDNAs were strategically selected to represent genes involved either in iron metabolism or in interlinked pathways (eg, oxidative stress, nitric oxide [NO] metabolism, or copper metabolism), and were immobilized on glass slides. HeLa cells were treated with iron donors or iron chelators, or were subjected to oxidative stress (H(2)O(2)) or NO (sodium nitroprusside). In addition, we generated a stable transgenic HeLa cell line expressing the HFE gene under an inducible promoter. Gene-response patterns were recorded for all of these interrelated experimental stimuli, and analyzed for common and distinct responses that define signal-specific regulatory patterns. The resulting regulatory patterns reveal and define degrees of relationship between distinct signals. Remarkably, the gene responses elicited by the altered expression of the hemochromatosis protein HFE and by pharmacological iron chelation exhibit the highest degree of relatedness, both for iron-regulatory protein (IRP) and non-IRP target genes. This finding suggests that HFE expression directly affects the intracellular chelatable iron pool in the transgenic cell line. Furthermore, cells treated with the iron donors hemin or ferric ammonium citrate display response patterns that permit the identification of the iron-loaded state in both cases, and the discrimination between the sources of iron loading. These findings also demonstrate the broad utility of gene-expression profiling with the IronChip to study iron metabolism and related human diseases.

Sauchinone, a lignan from Saururus chinensis, suppresses iNOS expression through the inhibition of transactivation activity of RelA of NF-kappaB.

Sauchinone, a known lignan, was isolated from the root of Saururus chinensis as an active principle responsible for inhibiting the production of NO in LPS-stimulated RAW264.7 cells by activity-guided fractionation. Sauchinone dose-dependently inhibited not only the production of NO, but also the expression of iNOS mRNA and protein in LPS-stimulated RAW 264.7 cells. Furthermore, sauchinone prevented LPS-induced NF-kappaB activation, which is known to play a critical role in iNOS expression, assessed by a reporter assay under the control of NF-kappaB. However, an electrophoretic mobility shift assay (EMSA) demonstrated that sauchinone did not suppress the DNA-binding activity of NF-kappaB or the degradation of IkappaB-alpha induced by LPS. Further analysis revealed that transactivation activity of RelA subunit of NF-kappaB was dose-dependently suppressed in the presence of sauchinone. Taken together, our results suggested that sauchinone could inhibit production of NO in LPS-stimulated RAW264.7 cells through the suppression of NF-kappaB by inhibiting transactivation activity of RelA subunit.