OBJECTIVETo investigate the effect of curcumin on STAT 5 signaling molecule in K562 cells and its molecular mechanism of antileukemia.

METHODSCell proliferation was studied by tetrazolium dye assay. The expressions of STAT5 mRNA and protein were assayed by in situ hybridization, and Western blotting respectively.

RESULTSCurcumin could inhibit K562 cell proliferation in a time- and dose-dependent manner. The percentage of STAT5-positive cells was 19% in curcunin group, significantly less than 31% of that in K562 cell group (P < 0.01). The A value of the expression level of STAT5 protein in curcumin group was 15 266 +/- 769, significantly less than 25 781 +/- 1240 of that in K562 cell group (P < 0.01).

CONCLUSIONThe expressions of STAT5 mRNA and protein in K562 cells were inhibited by curcumin and curcumin could inhibit K562 cell proliferation.

Cell Proliferation ; drug effects ; Curcumin ; pharmacology ; Gene Expression Regulation, Leukemic ; drug effects ; Humans ; K562 Cells ; Leukemia ; genetics ; metabolism ; physiopathology ; STAT5 Transcription Factor ; genetics ; metabolism ; Signal Transduction ; drug effects

Gap junctions mediate direct communication between cells; however, toxicological cascade triggered by nonessential metals can abrogate cellular signaling mediated by gap junctions. Although cadmium (Cd) is known to induce apoptosis in organs and tissues, the mechanisms that underlie gap junction activity in Cd-induced apoptosis in BRL 3A rat liver cells has yet to be established. In this study, we showed that Cd treatment decreased the cell index (a measure of cellular electrical impedance) in BRL 3A cells. Mechanistically, we found that Cd exposure decreased expression of connexin 43 (Cx43), increased expression of p-Cx43 and elevated intracellular free Ca2+ concentration, corresponding to a decrease in gap junctional intercellular communication. Gap junction blockage pretreatment with 18β-glycyrrhizic acid (GA) promoted Cd-induced apoptosis, involving changes in expression of Bax, Bcl-2, caspase-3 and the mitochondrial transmembrane electrical potential (Δψm). Additionally, GA was found to enhance ERK and p38 activation during Cd-induced activation of mitogen-activated protein kinases, but had no significant effect on JNK activation. Our results indicated the apoptosis-related proteins and the ERK and p38 signaling pathways may participate in gap junction blockage promoting Cd-induced apoptosis in BRL 3A cells.
Animals ; Apoptosis/*drug effects ; Cadmium/*toxicity ; Calcium/metabolism ; Cell Communication/drug effects ; Connexin 43/genetics ; Enzyme Activation/drug effects ; Gap Junctions/*drug effects ; Gene Expression Regulation/drug effects ; Hepatocytes/cytology/*drug effects ; Rats ; Signal Transduction/drug effects

OBJECTIVEThis study measures the glutaredoxin (Grx) gene and protein expression in umbilical vein endothelial cells upon exposure to Porphyromonas gingivalis (P. gingivalis) lipopolysaccharide (LPS). The involvement of the Akt-signaling pathway is also determined.

METHODSEA-hy926 cells were pretreated with 1,000 ng · mL⁻¹ P. gingivalis LPS for 4, 12, 18, and 24 h, and then real-time reverse transcription polymerase chain reaction was employed to detect Grx1 expression. The effect of Grx on Akt activity was investigated using Western blot for the control, LPS (1,000 ng · mL⁻¹ LPS), and carmus- tine (BCNU) groups (1,000 ng · mL⁻¹ LPS, and the EA-hy926 cells were pretreated with 25 μmol · ml⁻¹ BCNU for 30 min).

RESULTSGene expression of Grx1 significantly increased in LPS group compared with that in the control group. The Grx1 expression reached the peak level in 12 h, and the variation between the expression in 4 and 12 h was significant (P < 0.05). After 12 h, the protein levels of Grx and phosphorylated-Akt (p-Akt) significantly increased in the LPS group (P < 0.05), whereas the BCNU group showed a considerable decrease in both Grx and p-Akt expression levels (P < 0.05). Moreover, a slight difference was observed in the total Akt protein levels in the three groups (P > 0.05).

CONCLUSIONGrx expression increased upon exposure of EA-hy926 cells to the LPS. Akt activity could be inhibited by BCNU (a Grx inhibitor), which indicated that Akt might act as a downstream regulator of Grx.

Endothelial Cells ; Glutaredoxins ; genetics ; Humans ; Lipopolysaccharides ; pharmacology ; Oxidative Stress ; drug effects ; Phosphorylation ; Porphyromonas gingivalis ; pathogenicity ; Proto-Oncogene Proteins c-akt ; drug effects ; Signal Transduction ; drug effects ; Umbilical Veins

OBJECTIVETo explore the molecular mechanisms of arsenic trioxide (As2O3) inhibiting NB4 cells proliferation.

METHODSThe Janus kinase 1 (JAK1) protein level and its phosphorylation level in NB4 cells was detected by Western blots. NB4 cells were transfected with JAK1 siRNA or JAK1 plasmid to make JAK1 gene silenced or overexpressed. The inhibition of NB4 cells proliferation was measured by MTT assay and Trypan blue exclusion respectively. The variation of phosphorylation level of JAK1 and the cell cycle inhibitor P21 were determined by Western blots.

RESULTSJAK1 protein was expressed stably in NB4 cells, with no phosphorylation. The phosphorylation of JAK1 was enhanced after the NB4 cells treated with As2O3. After NB4 cells transfected with JAK1 siRNA, the expression level of JAK1 was obviously lower than that of in the non-specific siRNA group and blank control group. The effect of As2O3 inhibiting NB4 cells proliferation was weaker in the JAK1 siRNA transfected group. The inhibiting rate of 4 micromol/L As2O3 on NB4 cells proliferation of JAK1 siRNA group was 49.12% being lower than that of the non-specific siRNA group (74.58%) and control group (72.33%). After NB4 cells transfected with JAK1 plasmid, the JAK1 expression level in wild-type and mutant type plasmid groups were significantly higher than those in the empty plasmid group, moreover the effect of As2O3 inhibiting proliferation was stronger in wild-type plasmid group. The inhibiting rate of 4 micromol/L As2O3 on NB4 cells proliferation of wild-type plasmid group was 69.53% being higher than that of the mutant type JAK1 plasmid group (37.26%) and the empty plasmid group (39.61%). The expression level of P21 was up-regulated after the NB4 cells treated with As2O3.

CONCLUSIONJAK1 is expressed stably in NB4 cells, but has no activity. Arsenic trioxide inhibits the proliferation of NB4 cells through activating the JAK1. P21 is up-regulated after arsenic trioxide activated the JAK1 to inhibit the proliferation of NB4 cells.

Apoptosis ; drug effects ; Arsenicals ; pharmacology ; Cell Proliferation ; drug effects ; Humans ; Janus Kinase 1 ; genetics ; metabolism ; Oxides ; pharmacology ; Signal Transduction ; drug effects ; Tumor Cells, Cultured

The present study investigated the effects and underlying mechanism of ethylacetate fraction of Ribes fasciculatum (ERF) on the lifespan and stress tolerance using a Caenorhabditis elegans model. The longevity activity of ERF was determined by lifespan assay under normal culture condition. The survival rate of nematodes under various stress conditions was assessed to validate the effects of ERF on the stress tolerance. To determine the antioxidant potential of ERF, the superoxide dismutase (SOD) activities and intracellular reactive oxygen species (ROS) levels were investigated. The ERF-mediated change in SOD-3 expression was examined using GFP-expressing transgenic strain. The effects of ERF on the aging-related factors were investigated by reproduction assay and pharyngeal pumping assay. The intestinal lipofuscin levels of aged nematodes were also measured. The mechanistic studies were performed using selected mutant strains. Our results indicated that ERF showed potent lifespan extension effects on the wild-type nematode under both normal and various stress conditions. The ERF treatment also enhanced the activity and expression of superoxide dismutase (SOD) and attenuated the intracellular ROS levels. Moreover, ERF-fed nematodes showed decreased lipofuscin accumulation, indicating ERF might affect age-associated changes in C. elegans. The results of mechanistic studies indicated that there was no significant lifespan extension in ERF-treated daf-2, age-1, sir-2.1, and daf-16 null mutants, suggesting that they were involved in ERF-mediated lifespan regulation. In conclusion, R. fasciculatum confers increased longevity and stress resistance in C. elegans via SIR-2.1-mediated DAF-16 activation, dependent on the insulin/IGF signaling pathway.
Aging ; drug effects ; genetics ; metabolism ; Animals ; Caenorhabditis elegans ; drug effects ; genetics ; growth & development ; metabolism ; Caenorhabditis elegans Proteins ; genetics ; metabolism ; Humans ; Longevity ; drug effects ; Oxidative Stress ; drug effects ; Plant Extracts ; pharmacology ; Reactive Oxygen Species ; metabolism ; Ribes ; chemistry ; Signal Transduction ; drug effects

OBJECTIVETo study the expression changes of apoptosis related genes induced by cerulenin in multiple myeloma cell line U266 and explore its molecular mechanism.

METHODSThe expression changes of 96 apoptosis related genes were analyzed by superArray cDNA in U266 cells treated with cerulenin (20 microg/ml) for 12 h. Semi-quantitative RT-PCR was used to confirm the representative expression changes genes, Rip2, caspase 9 and TRAF2.

RESULTSAfter treated with cerulenin for 12 h, 44 apoptosis related genes expression in the U266 cells were changed, among which 41 were over 2 fold increase and 3 over 2 fold decrease. The expression of caspase 9 was increased markedly, indicating that mitochondria pathway played a key role in cerulenin inducing apoptosis and TRAF2 expression change suggested that nuclear factor (NF) participates in cerulenin inducing apoptosis.

CONCLUSIONThe death acceptor signaling pathway and the death acceptor non-dependence signaling pathway co-regulate cerulenin inducing apoptosis in U266 cells. Mitochondria pathway played the key role and nuclear factor (NF) participates in the apoptosis process.

Apoptosis ; drug effects ; genetics ; Cell Line, Tumor ; Cerulenin ; pharmacology ; Gene Expression Profiling ; Gene Expression Regulation, Neoplastic ; Humans ; Multiple Myeloma ; genetics ; metabolism ; pathology ; Signal Transduction ; drug effects

OBJECTIVETo search new clues to reveal the action mechanism of inhaled anesthetics.

METHODSThree kinds of Drosophila melanogaster were used as studied models: the wild type strain (H), the sevoflurane-sensitive strain (S), and the sevoflurane-resistant strain (R). Differential display reverse transcriptional-polymerase chain reaction method was performed to examine the differentially expressed fragments between Drosophila induced with and without sevoflurane. Rapid amplification of cDNA ends (RACE) method was used to clone the full length cDNA from positive differentially expressed fragments.

RESULTSThirty-one differentially expressed fragments were found between the two groups. Three fragments were identified as the positive differentially expressed fragments by Northern blot analysis. Two full-length cDNAs were cloned by RACE method, among which one was a 1.0 kb Drosophila calmodulin (CaM), located on Chr.2; the other was a 4.1 kb gene with unknown function (No.45), located on Chr.3.

CONCLUSIONThe two full-length cDNAs belong to the genes that related to anesthetic action pathway, which might participate in the regulation of cellular functions and signal transduction pathways. The two genes that we found should provide a novel way to study the mechanism of inhaled anesthetic action.

Anesthetics, Inhalation ; pharmacology ; Animals ; Cloning, Molecular ; DNA, Complementary ; Drosophila melanogaster ; drug effects ; genetics ; Gene Expression ; Methyl Ethers ; pharmacology ; Signal Transduction

Animals ; Keratolytic Agents ; pharmacology ; Neural Crest ; embryology ; metabolism ; Signal Transduction ; drug effects ; Tretinoin ; pharmacology ; Zebrafish ; Zebrafish Proteins ; genetics ; metabolism

OBJECTIVETo investigate the effect of lead exposure on the gene expression of fibroblast growth factor 3 (Fgf3) in zebrafish embryonic development and the mechanism of lead-induced embryonic developmental toxicity.

METHODSThe embryos of zebrafish (wild types A and B) were exposed to lead acetate (PbAc) at the doses of 0, 0.1, 0.5, 2.5, and 12.5 µmol/L separately. Total RNA was extracted from each treatment group of zebrafish embryos at 8, 12, 16, 24, 36, 48, and 72 hours post fertilization (hpf). The total mRNA expression of Fgf3 was measured by real-time quantitative PCR. The spatial expression of Fgf3 in zebrafish embryos was determined by whole-mount in situ hybridization using synthesized Fgf3 RNA probe.

RESULTSThe mRNA expression of Fgf3 in each group peaked at 12 hpf (P < 0.01). With the increase in PbAc concentration, the mRNA expression of Fgf3 rose. Compared with the mRNA expression level of Fgf3 in the control group, the relative mRNA expression levels of Fgf3 in the 0.1, 0.5, 2.5, and 12.5 µmol/L PbAc exposure groups were 1.02 ± 0.24, 1.05 ± 0.26, 1.22 ± 0.46, and 1.25 ± 0.38, respectively, and the 2.5 and 12.5 µmol/L PbAc exposure groups showed significantly higher Fgf3 expression than the control group (P < 0.05). The whole-mount in situ hybridization results showed that Fgf3 expression occurred mainly in the head and tail in the early stage of embryonic development and in the midbrain, fin bud, and pharyngeal arch in the middle/late stage of embryonic development; there were the most significant regions and intensities of positive hybridization signals at 12 hpf; but no significant differences were found between the control group and exposure groups in the location and intensity of Fgf3 expression

CONCLUSIONLead exposure can result in the upregulation of Fgf3 expression in zebrafish embryonic development, which might contribute to lead-induced embryonic developmental toxicity.

Animals ; Embryonic Development ; drug effects ; Fibroblast Growth Factor 3 ; genetics ; metabolism ; Gene Expression ; Organometallic Compounds ; adverse effects ; Signal Transduction ; Zebrafish ; embryology ; genetics ; metabolism ; Zebrafish Proteins ; genetics ; metabolism

Action mechanism and material base of compound Danshen dripping pills in treatment of carotid atherosclerosis were discussed based on gene expression profile and molecular fingerprint in this paper. First, gene expression profiles of atherosclerotic carotid artery tissues and histologically normal tissues in human body were collected, and were screened using significance analysis of microarray (SAM) to screen out differential gene expressions; then differential genes were analyzed by Gene Ontology (GO) analysis and KEGG pathway analysis; to avoid some genes with non-outstanding differential expression but biologically importance, Gene Set Enrichment Analysis (GSEA) were performed, and 7 chemical ingredients with higher negative enrichment score were obtained by Cmap method, implying that they could reversely regulate the gene expression profiles of pathological tissues; and last, based on the hypotheses that similar structures have similar activities, 336 ingredients of compound Danshen dripping pills were compared with 7 drug molecules in 2D molecular fingerprints method. The results showed that 147 differential genes including 60 up-regulated genes and 87 down regulated genes were screened out by SAM. And in GO analysis, Biological Process ( BP) is mainly concerned with biological adhesion, response to wounding and inflammatory response; Cellular Component (CC) is mainly concerned with extracellular region, extracellular space and plasma membrane; while Molecular Function (MF) is mainly concerned with antigen binding, metalloendopeptidase activity and peptide binding. KEGG pathway analysis is mainly concerned with JAK-STAT, RIG-I like receptor and PPAR signaling pathway. There were 10 compounds, such as hexadecane, with Tanimoto coefficients greater than 0.85, which implied that they may be the active ingredients (AIs) of compound Danshen dripping pills in treatment of carotid atherosclerosis (CAs). The present method can be applied to the research on material base and molecular action mechanism of TCM.
Carotid Artery Diseases ; drug therapy ; genetics ; metabolism ; Drugs, Chinese Herbal ; administration & dosage ; Gene Expression Profiling ; Gene Expression Regulation ; drug effects ; Humans ; Salvia miltiorrhiza ; chemistry ; Signal Transduction ; drug effects