OBJECTIVE: To investigate the molecular mechanism of trichloroethylene (TCE) cardiac developmental toxicity on zebrafish embryos and to try to provide experimental data for related intervention. METHODS: Zebrafish embryos were purchased from the National Zebrafish Resource Center. The embryos were divided into DMSO(control group), DMSO+CHIR, DMSO+XAV, TCE, TCE+CHIR and TCE+XAV groups(TCE at the concentration of 1, 10 and 100 ppb, with the DMSO as control; DMSO: Dimethyl suldoxide; CHIR: CHIR-99021, Wnt agonist; XAV: XAV-939, Wnt antagonist), 60 embryos per group. Zebrafish embryos were fed in systematic aquaculture water, 28℃. The water was replaced every 24 h and drugs were added according to the grouping scheme. The cardiac tissues were dissected and analyzed by transcriptome microarray after RNA extraction. The expressions of Wnt signaling pathway related genes were verified by q-PCR. Wnt atagonist XAV and activator CHIR were used alone or in combination to further evaluate the possibility of the Wnt signaling participating in the cardiac developmental toxicity induced by TCE. RESULTS: Compared with control, Zebra fish embryos exposed to TCE showed a significant increase in heart defects, and the main phenotypes were abnormal atrioventricular ratio, looping defects and pericardial edema. The results of microarray profiling showed that the expressions of genes related to Wnt signaling pathway were affected significantly. The results of qPCR further confirmed that TCE inhibited the expressions of Wnt pathway target genes Axin2, Sox9b and Nkx2.5(P＜0.05). Wnt agonist CHIR reduced the TCE-induced cardiac malformation rate significantly, while the addition of Wnt antagonist XAV markedly enhanced the cardiac developmental toxicity of TCE. CONCLUSION Exposure to TCE leads to heart malformation in zebrafish embryos. Wnt signaling pathway may be involved in the cardiac developmental toxicity induced by TCE.
Animals ; Gene Expression Regulation, Developmental ; drug effects ; Heart ; drug effects ; embryology ; Transcriptome ; Trichloroethylene ; adverse effects ; Wnt Signaling Pathway ; drug effects ; Zebrafish

OBJECTIVETo investigate the effect of indomethacin on the proliferation and Wnt/β-catenin pathway in K562 cells.

METHODSThe cell growth of K562 cells treated with different concentrations of indomethacin was assessed with MTT assay, and the colony-forming ability of the cells was evaluated by colony-forming assay. The mRNA expressions of BCR/ABL and β-catenin were detected by RT-PCR, and the protein expressions of pBCR/ABL, total BCR/ABL, β-catenin, pGSK-3β and c-myc were analyzed by Western blotting.

RESULTSIndomethacin significantly suppressed the growth and colony-forming ability of K562 cells in a dose-dependent manner. Indomethacin treatment dose-dependently decreased the protein level of pBCR/ABL and total BCR/ABL without affecting bcr-abl mRNA expressions. Compared with the control groups, indomethacin-treated cells showed obviously decreased mRNA and protein expressions of β-catenin and decreased protein expressions of pGSK-3β and c-myc.

CONCLUSIONIndomethacin inhibits the proliferation of K562 cells by suppressing the activity of bcr-abl-Wnt/β-catenin pathway.

Cell Cycle ; Cell Proliferation ; Fusion Proteins, bcr-abl ; metabolism ; Humans ; Indomethacin ; pharmacology ; K562 Cells ; drug effects ; RNA, Messenger ; Wnt Signaling Pathway ; drug effects ; beta Catenin ; metabolism

In gliomas, the canonical Wingless/Int (WNT)/β-catenin pathway is increased while peroxisome proliferator-activated receptor gamma (PPAR-γ) is downregulated. The two systems act in an opposite manner. This review focuses on the interplay between WNT/β-catenin signaling and PPAR-γ and their metabolic implications as potential therapeutic target in gliomas. Activation of the WNT/β-catenin pathway stimulates the transcription of genes involved in proliferation, invasion, nucleotide synthesis, tumor growth, and angiogenesis. Activation of PPAR-γ agonists inhibits various signaling pathways such as the JAK/STAT, WNT/β-catenin, and PI3K/Akt pathways, which reduces tumor growth, cell proliferation, cell invasiveness, and angiogenesis. Nonsteroidal anti-inflammatory drugs, curcumin, antipsychotic drugs, adiponectin, and sulforaphane downregulate the WNT/β-catenin pathway through the upregulation of PPAR-γ and thus appear to provide an interesting therapeutic approach for gliomas. Temozolomide (TMZ) is an antiangiogenic agent. The downstream action of this opposite interplay may explain the TMZ-resistance often reported in gliomas.
Animals ; Brain Neoplasms ; metabolism ; therapy ; Dacarbazine ; analogs & derivatives ; pharmacology ; Down-Regulation ; drug effects ; Glioma ; metabolism ; therapy ; Humans ; PPAR gamma ; metabolism ; Temozolomide ; Wnt Signaling Pathway ; drug effects ; physiology

OBJECTIVE: To investigate the effect of Quercetin (Qu) on cell proliferation, apoptosis and cell cycle, as well as the expression changes of Wnt/β-catenin signaling pathway, apoptosis and cell cycle regulators and BCR-ABL in CML susceptible cells K562 and imatinib-resistant cells (IM) K562R. METHODS: The trypan blue staining was used to detect the all proliferation. The cell cycle and apoptosis were detected by flow cytometry. The fluorescence quantitative PCR and Western blot were used to detect the expression of mRNA and protein respectively. RESULTS: After administration with 5, 10, 20, 40, 80, 160, 320 μmol/L Qu, the inhibition ratio in K562 cells was 5.07%, 5.98%, 11.09%, 31.88%, 56.89%, 70.44%, 86.63%; and that in K562R cells were 4.99%, 9.75%, 10.54%, 8.93%, 25.13%, 46.89%, 68.60%; IC of K562 and K562R was 76.4 μmol/L and 230.2 μmol/L, respectively. Flow cytometry showed that Qu (50, 100 and 200 μmol/L) could induce cell apoptosis and cell cycle arrest in a dose-dependent manner (r=0.9914, r=0.9871 respectively). After treatment with Qu (100 μmol/L)，the expressions of mRNA (P＜0.05) and protein(except Caspase-9) expression of Caspase-3, 8 and 9, p21 and p27 increased in K562 cells as compared with control, but the protein expression of p27 and Caspase-3 not changed in K562R. Qu (100 μmol/L) could decrease the mRNA(P＜0.05) and protein levels of Wnt/β-catenin signaling pathway members GSK-3β, β-catenin, Lef-1 and the downstream targets PPAR-δ and Cyclin D1 compared with control. The PCR results showed that Qu could reduce the BCR-ABL mRNA expression in CML cells, but the protein expression of BCR-ABL and p-BCR-ABL not obviouly changed. CONCLUSION Qu can inhibit the proliferation K562 and K562R cells, and decrease the drug resistance and increase the sensitivity, that relate with inhibiting Wnt/β-catenin signaling pathway, activating apoptosis pathway and cyclins.
Apoptosis ; Cell Proliferation ; Drug Resistance, Neoplasm ; Glycogen Synthase Kinase 3 beta ; Humans ; K562 Cells ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive ; Quercetin ; Wnt Signaling Pathway ; drug effects ; beta Catenin

In order to investigate the roles of Wnt signal pathway in transformation of cardiac valvular myofibroblasts to the osteoblast-like phenotype, the primary cultured porcine aortic valve myofibroblasts were incubated with oxidized low density lipoprotein (ox-LDL, 50 mg/L), and divided into four groups according to the ox-LDL treatment time: control group, ox-LDL 24-h group, ox-LDL 48-h group, and ox-LDL 72-h group. Wnt signal pathway blocker Dickkopf-1 (DDK-1, 100 μg/L) was added in ox-LDL 72-h group. The expression of a-smooth muscle actin (α-SMA), bone morphogenetic protein 2 (BMP2), alkaline phosphatase (ALP), and osteogenic transcription factor Cbfa-1 was detected by Western blotting, and that of β-catenin, a key mediator of Wnt signal pathway by immunocytochemical staining method. The Wnt/β-catenin was observed and the transformation of myofibroblasts to the osteoblast-like phenotype was examined. The expression of α-SMA, BMP2, ALP and Cbfa-1 proteins in the control group was weaker than in the ox-LDL-treated groups. In ox-LDL-treated groups, the protein expression of a-SMA, BMP2, ALP, and Cbfa-1 was significantly increased in a time-dependent manner as compared with the control group, and there was significant difference among the three ox-LDL-treated groups (P<0.05 for all); β-catenin protein was also up-regulated in the ox-LDL-treated groups in a time-dependent manner as compared with the control group (P<0.05), and its transfer from cytoplasm to nucleus and accumulation in the nucleus were increased in the same fashion (P<0.05). After addition of DKK-1, the expression of α-SMA, bone-related proteins and β-catenin protein was significantly reduced as compared with ox-LDL 72-h group (P<0.05). The Wnt/ β-catenin signaling pathway may play an important role in transformation of valvular myofibroblasts to the osteoblast-like phenotype.
Actins ; metabolism ; Animals ; Aortic Valve ; cytology ; Cell Differentiation ; drug effects ; Cells, Cultured ; Gene Expression Regulation ; drug effects ; Intercellular Signaling Peptides and Proteins ; pharmacology ; Lipoproteins, LDL ; pharmacology ; Myofibroblasts ; drug effects ; Osteoblasts ; physiology ; Phenotype ; Swine ; Wnt Signaling Pathway ; drug effects ; beta Catenin ; metabolism

To explore the effects and molecular mechanisms of triptolide（TP）on improving podocyte epithelial-mesenchymal transition（EMT）induced by high dose of D-glucose（HG）, the immortalized podocytes of mice were divided into the normal group（N）, the high dose of D-glucose group（HG）, the low dose of TP group（L-TP）, the high dose of TP group（H-TP）and the mannitol group（MNT）, and treated by the different measures respectively. More specifically, the podocytes in each group were separately treated by D-glucose（DG, 5 mmol·L⁻¹）or HG（25 mmol·L⁻¹）or HG（25 mmol·L⁻¹）+ TP（3 μg·L⁻¹）or HG（25 mmol·L⁻¹）+ TP（10 μg·L⁻¹）or DG（5 mmol·L⁻¹）+ MNT（24.5 mmol·L⁻¹）. After the intervention for 24, 48 and 72 hours, firstly, the activation of podocyte proliferation was investigated. Secondly, the protein expression levels of the epithelial markers in podocytes such as nephrin and podocin, the mesenchymal markers such as desmin and collagen Ⅰ and the EMT-related mediators such as snail were detected respectively. Finally, the protein expression levels of Wnt3α and β-catenin as the key signaling molecules in Wnt3α/β-catenin pathway were examined severally. The results indicated that, HG could cause the low protein expression levels of nephrin and podocin and the high protein expression levels of desmin, collagen Ⅰ and snail in podocytes, and inducing podocyte EMT. On the other hand, HG could cause the high protein expression levels of Wnt3α and β-catenin in podocytes, and activating Wnt3α/β-catenin signaling pathway. In addition, L-TP had no effect on the activation of podocyte proliferation, the co-treatment of L-TP and HG could significantly recover the protein expression levels of nephrin and podocin, inhibit the protein expression levels of desmin, collagen I and snail in podocytes, thus, further improving podocyte EMT. And that, the co-treatment of L-TP and HG could obviously decrease the high protein expression levels of Wnt3α and β-catenin induced by HG in podocytes, and inhibit Wnt3α/β-catenin signaling pathway activation. On the whole, HG can induce podocyte EMT by activating Wnt3α/β-catenin signaling pathway; L-TP can ameliorate podocyte EMT through inhibiting Wnt3α/β-catenin signaling pathway activation, which may be one of the effects and molecular mechanisms .
Animals ; Cells, Cultured ; Diterpenes ; pharmacology ; Epithelial-Mesenchymal Transition ; Epoxy Compounds ; pharmacology ; Glucose ; Mice ; Phenanthrenes ; pharmacology ; Podocytes ; drug effects ; Wnt Signaling Pathway ; Wnt3A Protein ; metabolism ; beta Catenin ; metabolism

The discovery, sorting and identification methods as well as targeted drug delivery systems for cancer stem cells (CSCs) have been reviewed by consulting the recent research papers. CSCs have been believed to be responsible for the occurrence and development of chemo-resistance, leading to the failure of chemotherapy. Much progress has been made in the approaches for CSCs targeting drug delivery systems. The understanding and targeted drug delivery systems for CSCs are promising to provide an alternative for cancer therapy.
Animals ; Antineoplastic Agents ; pharmacology ; therapeutic use ; Apoptosis ; drug effects ; Drug Delivery Systems ; methods ; Drug Resistance, Neoplasm ; Flow Cytometry ; Humans ; Neoplasms ; drug therapy ; pathology ; Neoplastic Stem Cells ; drug effects ; pathology ; Signal Transduction ; drug effects ; Wnt Signaling Pathway ; drug effects

The Wnt/beta-catenin pathway has a role in osteoblast differentiation and bone formation. We screened 100 plant extracts and identified an extract from Euodia sutchuenensis Dode (ESD) leaf and young branch as an effective activator of the Wnt/beta-catenin pathway. ESD extract increased beta-catenin levels and beta-catenin nuclear accumulation in murine primary osteoblasts. The ESD extract also increased mRNA levels of osteoblast markers, including RUNX2, BMP2 and COL1A1, and enhanced alkaline phosphatase (ALP) activity in murine primary osteoblasts. Both ESD extract-induced beta-catenin increment and ALP activation were abolished by beta-catenin knockdown, confirming that the Wnt/beta-catenin pathway functions in osteoblast differentiation. ESD extract enhanced terminal osteoblast differentiation as shown by staining with Alizarin Red S and significantly increased murine calvarial bone thickness. This study shows that ESD extract stimulates osteoblast differentiation via the Wnt/beta-catenin pathway and enhances murine calvarial bone formation ex vivo.
Animals ; Cell Differentiation/*drug effects ; Evodia/*chemistry ; HEK293 Cells ; Humans ; Mice ; Osteoblasts/cytology/*drug effects/*metabolism ; Osteogenesis/drug effects ; Plant Extracts/chemistry/*pharmacology ; Skull/anatomy & histology/drug effects/metabolism ; Wnt Signaling Pathway/*drug effects ; beta Catenin/genetics/metabolism

Recent studies showed that activation of Wnt/β-catenin pathway promoted the differentiation of osteoblast-like cells in the arterial calcification, but its mechanism remains unknown. In this study, the hypothesis that Wnt/β-catenin pathway promotes the differentiation of osteoblast-like cells by upregulating the expression of receptor activator of NF-κB ligand (RANKL) was examined. LiCl was used to activate the Wnt/β-catenin pathway. The differentiation of osteoblast-like cells was observed by Von Kossa staining, calcium content assay, alkaline phosphatase (ALP) activity assay, and detection of osteocalcin expression. Real-time PCR was performed to detect the expression of RANKL and osteoprotegerin (OPG, the decoy receptor of RANKL) during the osteoblast-like cell differentiation. Different concentrations of OPG were added to the culture media respectively to inhibit the function of RANKL, and the change in the differentiation of osteoblast-like cells was evaluated. The results showed that when the Wnt/β-catenin pathway was activated by LiCl, the expression of RANKL was significantly increased, which coincided with the differentiation of osteoblast-like cells (P<0.05), and the OPG treatment could partly attenuate the promoting effect of Wnt/β-catenin pathway on the differentiation of osteoblast-like cells (P<0.05), but it failed to completely abolish such effect. It was concluded that activation of Wnt/β-catenin pathway promotes the differentiation of osteoblast-like cells by both RANKL-dependent and RANKL-independent mechanisms.
Animals ; Cell Differentiation ; drug effects ; Cells, Cultured ; Osteoblasts ; drug effects ; metabolism ; Osteogenesis ; drug effects ; RANK Ligand ; metabolism ; Rats ; Signal Transduction ; drug effects ; Wnt Signaling Pathway ; drug effects ; beta Catenin ; metabolism

OBJECTIVETo observe the expressions of Wnt/beta-catenin and the effects of tanshinone IIA (TII A) on Wnt/beta-catenin signaling pathway in high glucose induced renal tubular epithelial cell transdifferentiation.

METHODSHuman kidney proximal tubular epithelial cells (HK-2) were divided into three groups, i. e., the normal glucose group, the high glucose group, and the high glucose plus tanshinone IIA group. The expression of beta-catenin was observed using immunocytochemical staining. The protein expression of beta-catenin, E-cadherin, and alpha-smooth muscle actin (alpha-SMA) were detected by Western blot. The mRNA levels of beta-catenin and E-cadherin were detected by RT-PCR.

RESULTSCompared with the normal glucose group, both the protein and the mRNA expressions of beta-catenin were significantly enhanced (P < 0.01), the expression of E-cadherin significantly decreased (P < 0.01), the expression of beta-catenin increased in the cytoplasm and nucleus in the high glucose group. TIIA at the final concentration of 100 micromol/L significantly reduced the ectopic expression of beta-catenin. At that concentration, the protein and mRNA expressions of beta-catenin in the nucleus significantly decreased, while the protein and mRNA expressions of E-cadherin were up-regulated. Meanwhile, the expression of alpha-SMA obviously decreased.

CONCLUSIONSWnt/beta-catenin signaling pathway participated in the high glucose induced renal tubular epithelial cell transdifferentiation. TIIA inhibited the transdifferentiation process possibly through down-regulating the activities of Wnt/beta-catenin signaling pathway, thus further playing a role in renal protection.

Cadherins ; metabolism ; Cell Line ; Cell Transdifferentiation ; drug effects ; Diterpenes, Abietane ; pharmacology ; Epithelial Cells ; cytology ; drug effects ; metabolism ; Glucose ; adverse effects ; Humans ; Kidney Tubules, Proximal ; cytology ; drug effects ; metabolism ; Wnt Signaling Pathway ; drug effects ; beta Catenin ; metabolism