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2.
Gynecol Surg ; 14(1): 14, 2017.
Article in English | MEDLINE | ID: mdl-28890676

ABSTRACT

BACKGROUND: Pain can interfere with office procedures in gynaecology. The aim of this study is to measure the positive effect of music in gynaecological office procedures. METHODS: A randomized controlled trial was performed between October 2014 and January 2016. Women scheduled for an office hysteroscopy or colposcopy were eligible for randomization in the music group or control group. Stratification for hysteroscopy and colposcopy took place. The primary outcome is patients' level of pain during the procedure measured by the visual analogue scale (VAS). Secondary outcomes include patients' level of pain after the procedure, anxiety and satisfaction of patient and doctor. RESULTS: No positive effect of music on patients' perception of pain during the procedure was measured, neither for the hysteroscopy group (57 mm vs. 52 mm) nor for the colposcopy group (32 mm vs. 32 mm). Secondary outcomes were also similar for both groups. CONCLUSIONS: This study showed no positive effect of music on patients' level of pain, anxiety or satisfaction of patient or doctor for office hysteroscopy and colposcopy. We believe a multimodal approach has to be used to decrease patient distress in terms of pain and anxiety, with or without music. TRIAL REGISTRATION: Dutch Trial Register, NTR4924.

3.
BJOG ; 124(2): 277-282, 2017 Jan.
Article in English | MEDLINE | ID: mdl-28012272

ABSTRACT

OBJECTIVE: The Pictorial Blood Loss Assessment Chart (PBAC) is a validated tool that is used to diagnose heavy menstrual bleeding (HMB). Knowledge of the effect of its score and its relationship with outcome could have implications for using the PBAC as an outcome measurement in future HMB studies, and as a tool to evaluate the treatment effect in research and clinical practice. Our aim was to relate PBAC scores to other measures of success after endometrial ablation for HMB. DESIGN: Analysis of individual patient data (IPD) of randomised controlled trials studying women with HMB. SETTING: Women with HMB consulting their gynecologists. POPULATION OR SAMPLE: Individual patient data (IPD) of randomised controlled trials studying women with HMB. METHODS: We included studies if they had studied second-generation endometrial ablation techniques and had collected PBAC scores for both baseline and follow-up. The effectiveness of treatment was scored as satisfaction or re-intervention (yes/no) 12 months after treatment. We related these outcomes to the PBAC score at 12 months after treatment, and to PBAC decrease between baseline and 12 months of follow-up. RESULTS: We studied data for 900 patients included in nine studies. The median PBAC score at 12 months was 7 (0-2500). The overall satisfaction rate was 89% and the overall re-intervention rate was 7.2%. A clear association was found between absolute PBAC score at the 12-month follow-up and satisfaction (odds ratio, OR 0.16; 95% confidence interval, 95% CI 0.11-0.24) and surgical re-intervention (OR 2.3, 95% CI 1.8-2.8). A change in PBAC score was also associated with satisfaction (OR 2.0, 95% CI 1.7-2.3) and surgical re-intervention (OR 0.69, 95% CI 0.63-0.75). Both the absolute PBAC scores and the changes in score show high accuracy for both treatment outcomes. CONCLUSIONS: PBAC scores at 12 months after treatment are significantly associated with satisfaction and re-intervention rates. We propose to use the PBAC in research as a primary end point in studies on HMB, and in clinical practice as a measure to assess the effectiveness of treatment. TWEETABLE ABSTRACT: PBAC scores 12 months after treatment are significantly associated with satisfaction and reintervention rates.


Subject(s)
Endometrial Ablation Techniques , Menorrhagia/surgery , Outcome Assessment, Health Care/methods , Adult , Cohort Studies , Female , Humans , Middle Aged , Patient Satisfaction/statistics & numerical data , Randomized Controlled Trials as Topic , Reoperation/statistics & numerical data , Sensitivity and Specificity , Treatment Outcome
4.
Mar Pollut Bull ; 85(2): 816-23, 2014 Aug 30.
Article in English | MEDLINE | ID: mdl-24846297

ABSTRACT

Lactococcosis is prevalent on grey mullet (Mugil cephalus) in Hong Kong aquaculture resulting in serious economic loss. A compound formulation of Traditional Chinese Medicines (TCM) (modified Huanglian Jiedu decoction (HLJDD)) comprising Rhizoma coptidis, Radix scutellaria, Cortex phellodendri, Fructus gardeniae, Fructus forsythiae and Flos lonicerae japonicae (in a ratio of 3:2:2:3:3:5) were applied as feed supplements to deal with the disease. The Nitroblue tetrazolium activity in blood, bactericidal activity and total immunoglobulin in plasma were significantly enhanced after feeding 1% of this TCM for 28 days. The disease resistances to Lactococcus garvieae in 1% and 2% TCM feeding groups were significantly enhanced. In the in vitro study, the modified HLJDD also activated the plasma bactericidal activities (p<0.01). Based on this study, 1% modified HLJDD feeding for 28 days may be an optimal dose to prevent L. garvieae infection and could be used in aquaculture industries.


Subject(s)
Aquaculture , Disease Resistance/drug effects , Drugs, Chinese Herbal/therapeutic use , Fish Diseases/prevention & control , Lactococcus/immunology , Smegmamorpha/immunology , Animals , Drugs, Chinese Herbal/pharmacology , Fish Diseases/immunology , Hong Kong , Humans , Phytotherapy , Seafood , Smegmamorpha/blood
5.
Oral Oncol ; 50(5): 345-52, 2014 May.
Article in English | MEDLINE | ID: mdl-24333100

ABSTRACT

Nasopharyngeal carcinoma is well known to be a viral driven malignancy. Despite high loco-regional control rate with modern radiotherapy, distant metastasis remains as a major threat to the patients highlighting the importance of effective systemic therapy. Recent advances in the understanding of tumor biology, host cell-virus interaction and genetics have paved new ways for targeted therapies. This review summarizes the recent advances into our knowledge and understanding of NPC and highlights potential novel therapeutic strategies that may prove useful to treat this disease.


Subject(s)
Nasopharyngeal Neoplasms/pathology , Translational Research, Biomedical , Carcinoma , Humans , Nasopharyngeal Carcinoma , Nasopharyngeal Neoplasms/therapy , Nasopharyngeal Neoplasms/virology , Neoplasm Metastasis
7.
Horm Metab Res ; 44(11): 819-24, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22893262

ABSTRACT

Ginsenoside-Rb1 (Rb1), one of the bioactive components in ginseng extract, is recently reported to be able to promote adipogenesis and peroxisome proliferator-activated receptor gamma (PPARγ) expression. Meanwhile, microRNA-27b (miR-27b) is also identified to regulate adipogenesis by targeting PPARγ2. In the present study, we attempted to link up the Rb1-promoted adipogenesis with PPARγ binding and miR-27b regulation. First, we demonstrated that GW9662, an antagonist of PPARγ, could block Rb1-induced 3T3-L1 differentiation with little toxicity towards cell proliferation. Then, expression levels for both of miR-27b and its primary transcript, pri-mir-27b, were found to decrease upon Rb1 treatment. Again, GW9662 could attenuate the inhibitory effect of Rb1 on both miR-27 and pri-mir-27b expression. Since Rb1 was demonstrated to have binding activity towards PPARγ, we thus speculate that Rb1 may act though PPARγ to downregulate mir-27b gene transcription and mature miR-27b activity, which in turn promotes PPARγ expression and adipogenesis. Enhancement on adipogenesis of adipose tissues is expected to prevent lipotoxicty in nonadipose tissues. Our data may give a better illustration to explain the antidiabetic effect of Rb1 and provide a hint on treatment of lipid related metabolic diseases in the future.


Subject(s)
Adipogenesis/drug effects , Ginsenosides/pharmacology , MicroRNAs/genetics , PPAR gamma/genetics , Plant Extracts/pharmacology , Up-Regulation/drug effects , 3T3-L1 Cells , Adipocytes/cytology , Adipocytes/drug effects , Adipocytes/metabolism , Animals , Gene Expression Regulation/drug effects , Mice , MicroRNAs/metabolism , PPAR gamma/metabolism
8.
Mol Carcinog ; 51(12): 963-72, 2012 Dec.
Article in English | MEDLINE | ID: mdl-22006341

ABSTRACT

2-methoxyestradiol (2ME2), an endogenous metabolite of 17-ß-estradiol, has been shown to induce apoptosis and cell cycle arrest in various tumor models. We have previously shown that 2ME2 induced endoreduplication in a well-differentiated nasopharyngeal carcinoma (NPC) HK-1 and a poorly differentiated C666-1 cell line. In the present study, we studied the survival factors involved in 2ME2-induced endoreduplicating NPC cells. In the HK-1 cells, knockdown of BcL-xL expression by siRNA resulted in the reduction of endoreduplication and an increase in the percentage of apoptosis. Further mechanistic study revealed that 2ME2 enhanced the expression of the phosphorylated form of STAT5 (p-STAT5-Y694), but not p-STAT3 (Y705) and p-STAT3 (S727), in the nucleus of HK-1 cells. Pre-treatment of cells with JAK/STAT inhibitor AG490 and STAT5 inhibitor resulted not only in the reduced expression of Bcl-xL, but also reduced the percentage of endoreduplicating cells. In contrast, 2ME2 enhanced the expression of p-STAT3 in the poorly differentiated C666-1 cells. Pharmacological inhibition of STAT3 or Bcl-2/xL resulted in a decrease in endoreduplication of C666-1 cells. Taken together, the expression of p-STAT5 and p-STAT3 was upregulated in 2ME2-induced endoreduplicating HK-1 and C666-1 cells, respectively. Combination of 2ME2 with Bcl-2/xL inhibitor is a novel strategy to reduce the formation of endoreduplicating cells during chemotherapeutic treatment of NPC. © 2011 Wiley Periodicals, Inc.


Subject(s)
Endoreduplication/drug effects , Estradiol/analogs & derivatives , Nasopharyngeal Neoplasms/pathology , Proto-Oncogene Proteins c-bcl-2/physiology , STAT3 Transcription Factor/physiology , STAT5 Transcription Factor/physiology , bcl-X Protein/physiology , 2-Methoxyestradiol , Base Sequence , Blotting, Western , Carcinoma , Cell Line, Tumor , Estradiol/pharmacology , Flow Cytometry , Humans , Nasopharyngeal Carcinoma , RNA, Small Interfering
9.
Cell Biochem Funct ; 28(3): 239-48, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20373469

ABSTRACT

Photodynamic therapy (PDT) with a recently developed photosensitizer Zn-BC-AM was found to effectively induce apoptosis in a well-differentiated nasopharyngeal carcinoma (NPC) HK-1 cell line. Sustained activation of p38 mitogen-activated protein kinase (MAPK) and c-jun N-terminal kinase (JNK) as well as a transient increase in activation of extracellular signal-regulated kinase (ERK) were observed immediately after Zn-BC-AM PDT. A commonly used p38 MAPK/JNK pharmacological inhibitor PD169316 was found to reduce PDT-induced apoptosis of HK-1 cells. PD169316 also prevented the loss of Bcl-2 and Bcl-xL in PDT-treated HK-1 cells. However, inhibition of JNK with SP600125 had no effect on Zn-BC-AM PDT-induced apoptosis while inhibition of ERK with PD98059 or p38 MAPK with SB203580 significantly increased Zn-BC-AM PDT-induced apoptosis. Further study showed that knockdown of the p38beta isoform with siRNA also increased Zn-BC-AM PDT-induced apoptosis, indicating that the anti-apoptotic effect of PD169316 in PDT-treated HK-1 cells was probably independent of p38 MAPK or JNK activation. Taken together, the results suggest that inhibition of p38beta and ERK may enhance the therapeutic efficacy of Zn-BC-AM PDT on NPC cells. It should be noted that data only based on the use of PD169316 should be interpreted in caution.


Subject(s)
Apoptosis/drug effects , JNK Mitogen-Activated Protein Kinases/metabolism , Metalloporphyrins/pharmacology , Nasopharyngeal Neoplasms , Photochemotherapy/methods , Photosensitizing Agents/pharmacology , p38 Mitogen-Activated Protein Kinases/metabolism , Animals , Cell Line, Tumor , Enzyme Activation , Enzyme Inhibitors/metabolism , Extracellular Signal-Regulated MAP Kinases/genetics , Extracellular Signal-Regulated MAP Kinases/metabolism , Humans , JNK Mitogen-Activated Protein Kinases/antagonists & inhibitors , JNK Mitogen-Activated Protein Kinases/genetics , Nasopharyngeal Neoplasms/drug therapy , Nasopharyngeal Neoplasms/enzymology , Nasopharyngeal Neoplasms/pathology , Proto-Oncogene Proteins c-bcl-2/genetics , Proto-Oncogene Proteins c-bcl-2/metabolism , RNA, Small Interfering/genetics , RNA, Small Interfering/metabolism , p38 Mitogen-Activated Protein Kinases/antagonists & inhibitors , p38 Mitogen-Activated Protein Kinases/genetics
10.
J Biomol Screen ; 15(4): 427-33, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20208035

ABSTRACT

Cell migration plays a key role in both normal physiological and pathological conditions. The study of cell migration and its underlying mechanisms is of great significance in various fields of research, including basic biology and pharmaceutical development. The cell migration or scratch wounding assay is an easy and economical in vitro method that allows researchers to assess a large number of testing compounds. Even though this simple assay has been used for decades, researchers are still trying to modify such experimental protocols and wounding devices. In this study, an 8-channel mechanical "wounder" was designed for performing a cell migration assay, particularly in a 96-well culture plate format. With special designs of a guiding bar and adjustable pins for use with disposable pipette tips, this wounder confined the scratch area within the center of each well to ensure a perfect contact between the pins and the well surface. As a result, this mechanical wounder produces a uniform denudation of a cell monolayer in a 96-well plate with a wound size of around 600 microm. Using this improved wounding device, the effects of epidermal growth factor and DL-alpha-difluoromethylornithine on the reepithelialization of rat intestinal epithelial cells (IEC-6) and serum on the wound recovery of human umbilical vein endothelial cells were demonstrated. This wounder facilitates cell migration study and can be applicable for multiple sample analysis.


Subject(s)
Biological Assay/instrumentation , Biological Assay/methods , Cell Movement , Endothelial Cells/cytology , Epithelial Cells/cytology , Wound Healing , Animals , Calibration , Cell Line , Humans , Intestines/cytology , Rats , Stress, Mechanical , Umbilical Veins/cytology
11.
Ecotoxicol Environ Saf ; 73(4): 541-9, 2010 May.
Article in English | MEDLINE | ID: mdl-20153057

ABSTRACT

Sediments from Mai Po Ramsar site, Hong Kong were in general shown to be highly toxic based on the results of four toxicity tests (Microtox solid-phase test, Daphnia mortality test, algal [Microcystis aeruginosa] growth inhibition test and ryegrass [Lolium perenne] seed germination/root elongation test). Sediment of the mudflat (which is open to Deep Bay, i.e., the pollution source) was the most toxic while sediment of gei wai 24g (an enclosed freshwater pond) was the least toxic. Results of biomarker studies (tilapia hepatic metallothionein; glutathione (GSH) and EROD activity using H4IIE rat hepatoma cell) were also concordant with those in the toxicity tests. Significant liner relationships (p<0.01) were found between GSH contents in the rat hepatoma cells and PAHs, OCPs contents in the sediment extracts. It is recommended that the present suite of bioassays is useful and is biologically relevant for future ecotoxicological studies focusing on similar wetlands.


Subject(s)
Daphnia/drug effects , Environmental Monitoring , Geologic Sediments/analysis , Lolium/drug effects , Microcystis/drug effects , Water Pollutants, Chemical/toxicity , Wetlands , Animals , Biomarkers/analysis , Cell Line, Tumor , Cytochrome P-450 CYP1A1/metabolism , Ecotoxicology , Glutathione/analysis , Hong Kong , Hydrocarbons, Chlorinated/analysis , Hydrocarbons, Chlorinated/toxicity , Metallothionein/analysis , Metallothionein/toxicity , Polycyclic Aromatic Hydrocarbons/analysis , Polycyclic Aromatic Hydrocarbons/toxicity , Rats , Water Pollutants, Chemical/analysis
12.
Biochem Pharmacol ; 79(6): 825-41, 2010 Mar 15.
Article in English | MEDLINE | ID: mdl-19883629

ABSTRACT

2-Methoxyestradiol (2ME2) is a normal physiological metabolite of 17beta-estradiol with anti-proliferative and anti-angiogenic activities. The purpose of this study is to elucidate the mechanism whereby 2ME2 induces endoreduplication of the well-differentiated nasopharyngeal carcinoma (NPC) cells. We report here that 2ME2 induces G2/M phase cell cycle arrest followed by endoreduplication of the well-differentiated HK-1 cells. The increase in chromosome number was confirmed by cytogenetic study. Analysis of stress signaling pathways revealed the phosphorylation activation of ERK, JNK and p38 MAPKs at various times after 2ME2 treatment. Pre-treatment of 2ME2-treated HK-1 cells with JNK inhibitor (SP600125), ERK inhibitor (PD98059) and p38 MAPK inhibitor (SB203580) resulted in the reduction of endoreduplicating cells. Furthermore, the increase in the phosphorylation of JNK was accompanied by an increase in the reactive oxygen species. In addition, endoreduplication was observed in cells after treatment with superoxide donor, 2,3-dimethoxy-1,4-naphoquinone (DMNQ). Confocal microscopic analysis also revealed the increase in mitochondrial superoxide anion in 2ME2-treated HK-1 cells. Pre-treatment of HK-1 cells with superoxide dismutase mimetic 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) or overexpressing the mitochondrial enzyme MnSOD resulted in the reduction of phosphorylation of JNK and the formation of endoreduplicating cells. Furthermore, the tubulin filaments in cytoplasm remain intact in 2ME2-treated HK-1 cells after pre-treatment of TEMPO. Our results suggest that 2ME2 induces endoreduplication through the induction of oxidative stress and the activation of MAPK signal pathways. The biological significance of drug-induced endoreduplication will also be discussed.


Subject(s)
Estradiol/analogs & derivatives , MAP Kinase Signaling System/drug effects , Mitochondria/drug effects , Oxidative Stress/drug effects , Tubulin Modulators/pharmacology , 2-Methoxyestradiol , Cell Line , Cell Proliferation , Dose-Response Relationship, Drug , Enzyme Activation , Estradiol/pharmacology , Humans , Mitochondria/metabolism
13.
Photodiagnosis Photodyn Ther ; 6(2): 122-7, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19683213

ABSTRACT

OBJECTIVES: In this study, the early apoptotic events elicited by mTHPC-mediated photo-cytotoxicity were explored in a human nasopharyngeal carcinoma cell line (NPC/HK1). METHODS AND MATERIALS: NPC/HK1 cells (5 x 10(3)) were incubated with photosensitizer mTHPC (0.8 microg/ml) in chamber slides for 20h and subjected to light irradiation at 2J/cm(2) (LD(80)). Morphologic changes of treated cells were examined under light microscopy and confocal microscopy at 0-4h after the light irradiation. The early stage of apoptosis was detected by fluorescein-conjugated Annexin V (Annexin V-FITC) assay. Mitochondrial membrane damage and cytochrome c release were determined by flowcytometric analysis. Bcl-2 expression was measured by Western blot analysis. RESULTS: One hour after mTHPC-mediated photodynamic therapy (PDT), microscopic examination showed membrane blebbing and cell shrinkage. Annexin V-FITC assay showed that a considerable number of NPC/HK1 cells became apoptotic. Flowcytometric analysis showed that the cytochrome c was released at 1h after PDT. Bcl-2 expression also declined significantly compared to control groups. CONCLUSIONS: mTHPC-mediated photo-cytotoxicity can effectively induce early apoptotic responses in NPC/HK1 cells which might be modulated by mitochondrial damages and Bcl-2 inhibition.


Subject(s)
Apoptosis/drug effects , Mesoporphyrins/pharmacology , Nasopharyngeal Neoplasms/therapy , Photochemotherapy , Photosensitizing Agents/pharmacology , Cell Line, Tumor , Flow Cytometry , Humans
14.
Gut ; 58(2): 166-73, 2009 Feb.
Article in English | MEDLINE | ID: mdl-18978176

ABSTRACT

BACKGROUND: Oesophagitis is characterised by basal cell hyperplasia and activated eosinophils, which release mediators including major basic protein (MBP). MBP and its mimetic polyarginine activate the calcium sensing receptor (CaSR) on oesophageal epithelium. Fibroblast growth factor 9 (FGF9) is implicated in epithelial homeostasis and proliferative response to injury, but has not been characterised in the oesophagus. OBJECTIVE: To characterise FGF9 in oesophageal epithelium and oesophagitis, as the result of MBP activation of the CaSR. METHODS: Human oesophageal epithelial cells (HET-1A) were used to compare affects of calcium, polyarginine and MBP-peptide on FGF9. HET-1A were transfected with interfering RNA (siRNA(CaSR)). FGF9, FGF receptors 2 and 3, bone morphogenetic protein (BMP)-2, BMP-4 and noggin mRNA expression were detected by reverse transcriptase polymerase chain reaction. FGF9 was measured from HET-1A and from normal, gastro-oesophageal reflux and eosinophilic oesophagitis (EoE) patient biopsies using ELISA and immunohistochemistry. HET-1A proliferation was studied using bromodeoxyuridine and MTT. RESULTS: FGF9 was secreted by HET-1A cells treated with polyarginine and MBP-peptide, but not calcium. This effect was abrogated by siRNA(CaSR). FGF9 receptor mRNA was present. HET-1A cells proliferated following rhFGF9, but not MBP-peptide treatment, and rhFGF9 altered transcription of downstream proliferation-related genes (noggin, BMP-2 and BMP-4). FGF9 was increased in biopsies from patients with eosinophilic oesophagitis, which correlated with basal hyperplasia. CONCLUSION: Eosinophil-released MBP acts on the CaSR to increase FGF9 in oesophageal epithelial cells, leading to proliferation. Increased FGF9 is found in biopsies of EoE patients and may play a role in the pathogenesis of oesophagitis.


Subject(s)
Eosinophilia/metabolism , Esophagitis/immunology , Esophagus/immunology , Fibroblast Growth Factor 9/pharmacology , Adolescent , Bone Morphogenetic Proteins/genetics , Calcium/metabolism , Calcium/pharmacology , Cell Line, Tumor , Cell Proliferation/drug effects , Child , Child, Preschool , Eosinophil Major Basic Protein/metabolism , Eosinophil Major Basic Protein/pharmacology , Eosinophilia/pathology , Epithelial Cells/immunology , Epithelial Cells/metabolism , Epithelial Cells/pathology , Esophagitis/metabolism , Esophagitis/pathology , Esophagus/metabolism , Esophagus/pathology , Female , Fibroblast Growth Factor 9/analysis , Fibroblast Growth Factor 9/genetics , Humans , Male , Peptides/metabolism , Peptides/pharmacology , RNA, Messenger/analysis , RNA, Small Interfering/pharmacology , Receptor, Fibroblast Growth Factor, Type 2/genetics , Receptor, Fibroblast Growth Factor, Type 3/genetics , Receptors, Calcium-Sensing/metabolism , Recombinant Proteins/pharmacology , Reverse Transcriptase Polymerase Chain Reaction/methods , Transcription, Genetic/drug effects
15.
Toxicology ; 247(2-3): 145-53, 2008 May 21.
Article in English | MEDLINE | ID: mdl-18406507

ABSTRACT

Benzo[a]pyrene (BaP) is a potentially genotoxic and cytotoxic environmental pollutant. Previous studies showed that exposure of HepG(2) cells to BaP causes necrotic cell death [Lin, T., Yang, M.S., 2007b. Cell death induced by benzo[a]pyrene in the HepG(2) cells is dependent on PARP-1 activation and NAD depletion. Toxicology 245, 147-153]. In the present study, the signaling pathways associated with this response was studied. BaP induced accumulation and activation of p53 in HepG(2) cells, which occurred as early as 12h after exposure. Activation of p53 was evidenced by its phosphorylation at serine 15 (Ser15) and acetylation at lysine 382 (Lys382). Chemical inhibition and siRNA-mediated knockdown of p53 expression suppressed its phosphorylation as well as cell death. BaP also activated p38 MAPK and ERK, but not JNK, at 6h after exposure. SB203580 and PD98059, specific inhibitors of p38 MAPK and ERK, respectively, suppressed phosphorylation of p53 at Ser15, but the accumulation of p53 was only moderately reduced. Acetylation of p53 at Lys 382 was not affected by these inhibitors, suggesting that acetylation stabilizes p53 in response to DNA damage. SB203580 and PD98059 prevented downstream energy failure and BaP-induced cell death. Similar results were obtained with siRNA against two isoforms of p38 MAPK, p38alpha and p38beta. Wortmannin, selective inhibitor of DNA-PK and ATM/ATR, abolished p53 phosphorylation, indicating an involvement of multiple pathways of p53 phosphorylation upon exposure to BaP. In summary, the current study demonstrated that both MAPK and p53 activation are required for BaP-induced necrotic cell death. The results also provide a novel model for studying the regulation between p53 and p38 MAPK in the progression of cellular necrosis.


Subject(s)
Apoptosis/drug effects , Benzo(a)pyrene/toxicity , Extracellular Signal-Regulated MAP Kinases/physiology , Tumor Suppressor Protein p53/physiology , p38 Mitogen-Activated Protein Kinases/physiology , Acetylation , Cells, Cultured , Flavonoids/pharmacology , Glutathione/metabolism , Humans , Phosphorylation , RNA, Small Interfering/pharmacology , Signal Transduction
16.
Biomed Pharmacother ; 61(9): 591-5, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17905565

ABSTRACT

Daidzein (4',7-dihydroxyisoflavone) and genistein (4',5,7-trihydroxyisoflavone) are two major isoflavones found predominantly in soy beans, as well as in certain traditional Chinese medicinal herbs and tea leaves. In the past decade, there have been extensive studies on the anti-tumor effects of genistein on cancers of the breast, prostate and colon in humans. However, the anti-tumor effects of daidzein on neuronal cancer cells and its action mechanisms remain poorly understood. In this study, daidzein was shown to inhibit the proliferation of a number of murine and human neuroblastoma cell lines in vitro. Using the murine neuroblastoma Neuro-2a (BU-1) cells as the cell model, daidzein was also found to prevent the cell cycle progression to G2/M phase and induced apoptosis of the neuronal tumor cells, as measured by flow cytometry and gel electrophoresis for fragmented DNA respectively. Taken together, our results showed that daidzein could exert pleiotropic effects on the murine neuroblastoma cells, including inhibition of cell proliferation, modulation of cell cycle check point regulation, and triggering of neuronal cell apoptosis.


Subject(s)
Antineoplastic Agents, Phytogenic , Brain Neoplasms/drug therapy , Estrogens, Non-Steroidal/pharmacology , Isoflavones/pharmacology , Neuroblastoma/drug therapy , Animals , Apoptosis/drug effects , Brain Neoplasms/pathology , Cell Cycle/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , DNA Fragmentation/drug effects , Flow Cytometry , Indicators and Reagents , Kinetics , Mice , Neuroblastoma/pathology , Tetrazolium Salts , Thiazoles
17.
Neuroscience ; 148(4): 915-24, 2007 Sep 21.
Article in English | MEDLINE | ID: mdl-17825492

ABSTRACT

We have investigated the neurite growth-stimulating properties of euxanthone, a xanthone derivative isolated from the Chinese medicinal plant Polygala caudata. Euxanthone was shown to exert a marked stimulatory action on neurite outgrowth from chick embryo dorsal root ganglia explanted in collagen gels, in the absence of added neurotrophins. It was also shown to promote cell survival in explanted chick embryo ganglia, and to stimulate neurite outgrowth from isolated adult rat primary sensory neurons in vitro. The further finding that euxanthone stimulates neurite outgrowth from explants of chick embryo retina and ventral spinal cord suggests an action on signaling pathways downstream of neuronal receptors for specific neurotrophic factors. Consistent with this, euxanthone did not promote neurite outgrowth from non-transfected PC12 cells, or from PC12 cells transfected with TrkB or TrkC, under conditions in which these cells extended neurites in response to, respectively, the neurotrophins nerve growth factor, brain-derived neurotrophic factor and neurotrophin 3. Western blot analysis of euxanthone-stimulated dorsal root ganglion explants showed that expression of phospho-mitogen-activated protein (MAP) kinase was up-regulated after 1 h of euxanthone-treatment. Inhibition of the MAP kinase pathway using PD98059, a specific inhibitor of MAP kinase kinase, blocked all euxanthone-stimulated neurite outgrowth. However, analysis of phospho-Akt expression indicated that the phosphatidylinositol-3 kinase-Akt pathway, another major signaling pathway engaged by neurotrophins, is not significantly activated by euxanthone. These results suggest that euxanthone promotes neurite outgrowth by selectively activating the MAP kinase pathway.


Subject(s)
Neurites/drug effects , Neurons/ultrastructure , Plant Extracts/pharmacology , Xanthones/pharmacology , Animals , Cells, Cultured , Chick Embryo , Coculture Techniques/methods , Collagen/physiology , Dose-Response Relationship, Drug , Ganglia, Spinal/cytology , Nerve Growth Factor/pharmacology , Neurons/drug effects , Organ Culture Techniques , Plant Extracts/chemistry , Rats , Rats, Sprague-Dawley , Receptor, trkB/physiology , Receptor, trkC/physiology , Signal Transduction/drug effects , Signal Transduction/physiology , Transfection/methods , Xanthones/chemistry
18.
Br J Pharmacol ; 152(2): 207-15, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17603552

ABSTRACT

BACKGROUND AND PURPOSE: Angiogenesis is a crucial step in tumour growth and metastasis. Ginsenoside-Rb1 (Rb1), the major active constituent of ginseng, potently inhibits angiogenesis in vivo and in vitro. However, the underlying mechanism remains unknown. We hypothesized that the potent anti-angiogenic protein, pigment epithelium-derived factor (PEDF), is involved in regulating the anti-angiogenic effects of Rb1. EXPERIMENTAL APPROACHES: Rb1-induced PEDF was determined by real-time PCR and western blot analysis. The anti-angiogenic effects of Rb1 were demonstrated using endothelial cell tube formation assay. Competitive ligand-binding and reporter gene assays were employed to indicate the interaction between Rb1 and the oestrogen receptor (ER). KEY RESULTS: Rb1 significantly increased the transcription, protein expression and secretion of PEDF. Targeted inhibition of PEDF completely prevented Rb1-induced inhibition of endothelial tube formation, suggesting that the anti-angiogenic effect of Rb1 was PEDF specific. Interestingly, the activation of PEDF occurred via a genomic pathway of ERbeta. Competitive ligand-binding assays indicated that Rb1 is a specific agonist of ERbeta, but not ERalpha. Rb1 effectively recruited transcriptional activators and activated an oestrogen-responsive reporter gene. Furthermore, Rb1-mediated PEDF activation and the subsequent inhibition of tube formation were blocked by the ER antagonist ICI 182,780 or transfection of ERbeta siRNA, indicating ERbeta dependence. CONCLUSIONS AND IMPLICATIONS: Here we show for the first time that the Rb1 suppressed the formation of endothelial tube-like structures through modulation of PEDF via ERbeta. These findings demonstrate a novel mechanism of the action of this ginsenoside that may have value in anti-cancer and anti-angiogenesis therapy.


Subject(s)
Angiogenesis Inhibitors/pharmacology , Endothelial Cells/drug effects , Estrogen Receptor beta/agonists , Eye Proteins/metabolism , Ginsenosides/pharmacology , Nerve Growth Factors/metabolism , Serpins/metabolism , Cell Line , Endothelial Cells/physiology , Estradiol/analogs & derivatives , Estradiol/pharmacology , Estrogen Antagonists/pharmacology , Estrogen Receptor beta/antagonists & inhibitors , Estrogen Receptor beta/genetics , Estrogen Receptor beta/metabolism , Fulvestrant , Humans , RNA, Messenger/metabolism
19.
Curr Med Chem ; 14(12): 1371-80, 2007.
Article in English | MEDLINE | ID: mdl-17504218

ABSTRACT

Panax ginseng C.A. Meyer, one of the most popular and valued herbs, has been used extensively in traditional Chinese medicine for thousands of years. More than thirty ginsenosides, the pharmacologically active ingredients in ginseng, have been identified with various sugar moieties attached at the C-3, C-6 and C-20 positions of the steroidal skeleton. We herein review the current literature on the pharmacological effects of ginsenosides on the modulation of angiogenesis, dysregulations of which contribute towards many pathological conditions. Regarding the adaptogenic property of ginseng, the effects of ginsenosides on central nervous system are also discussed. Recent researches have pointed to the steroid hormone receptors as the target molecules to elicit the diverse cellular and physiological activities of ginseng. We believe that understanding the interaction between ginsenosides and various steroid hormone receptors may provide clues to unravel the secret of ginseng.


Subject(s)
Ginsenosides/pharmacology , Neovascularization, Physiologic/drug effects , Neuroprotective Agents/pharmacology , Angiogenesis Inhibitors/pharmacology , Animals , Cognition/drug effects , Endothelium, Vascular/cytology , Endothelium, Vascular/drug effects , Ginsenosides/therapeutic use , Humans , Models, Molecular , Neurodegenerative Diseases/drug therapy
20.
Neuropharmacology ; 52(3): 827-35, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17123556

ABSTRACT

Ginsenoside-Rg1, the pharmacologically active component isolated from ginseng, demonstrated neuroprotective effects on primary cultured rat nigral neurons against rotenone toxicity. Rotenone, a common household pesticide known for its specific and irreversible mitochondria complex I inhibition, has been suggested to be the causal agent of Parkinson's disease (PD) by inducing degeneration of cells in the substantial nigra. The present study demonstrated that co-treatment of rotenone and Rg1 could reduce rotenone-induced cell death by 58% (SEM=+/-5.60; N=3). Rotenone-induced mitochondria membrane potential (MMP, DeltaPsim) depletion was restored and elevated by at least 38% (SEM=+/-2.15; N=3) by Rg1. In addition, Rg1 prevented cytochrome c release from the mitochrondrial membrane and increased the phosphorylation inhibition of the pro-apoptotic protein Bad through activation of the PI3K/Akt pathway. The protective effects of Rg1 was blocked by glucocorticoid receptor antagonist RU486, indicating that the action of Rg1 is mediated through glucocorticoid receptor (GR). In conclusion, Rg1 inhibits the mitochondrial apoptotic pathway and increases the survival chance of the primary cultured nigral neurons against rotenone toxicity. Thus, Rg1 and its related compounds may be developed as protective agents against neurodegenerative diseases induced by mitochondrial toxins.


Subject(s)
Ginsenosides/pharmacology , Insecticides/toxicity , Neurons/drug effects , Neuroprotective Agents/pharmacology , Rotenone/toxicity , Substantia Nigra/cytology , Analysis of Variance , Animals , Cell Survival/drug effects , Cells, Cultured , Cytochromes c/metabolism , Dose-Response Relationship, Drug , Drug Interactions , Enzyme Inhibitors/pharmacology , Hormone Antagonists/pharmacology , Mifepristone/pharmacology , Mitochondrial Membranes/drug effects , Rats , Rats, Sprague-Dawley , Time Factors , Tyrosine 3-Monooxygenase/metabolism , bcl-Associated Death Protein/metabolism
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