u-0126 and plerixafor

The aim of the present study was to investigate the effects of lipopolysaccharide (LPS) on the migration and adhesion of human dental pulp stem cells (hDPSCs) and the associated intracellular signalling pathways.. hDPSCs obtained from impacted third molars were exposed to LPS and in vitro cell adhesion and migration were evaluated. The effects of LPS on gene expression of adhesion molecules and chemotactic factors were investigated using quantitative real-time reverse-transcriptase polymerase chain (qRT-PCR). The potential involvement of nuclear factor NF-kappa-B (NF-κB) or mitogen-activated protein kinase (MAPK) signalling pathways in the migration and adhesion of hDPSCs induced by LPS was assessed using a transwell cell migration assay and qRT-PCR.. LPS promoted the adhesion of hDPSCs at 1μg/mL and 10μg/mL concentrations, 1μg/mL LPS showing the greater effect. Transwell cell migration assay demonstrated that LPS increased migration of hDPSCs at 1μg/mL concentration while decreasing it significantly at 10μg/mL. The mRNA expressions of adhesion molecules and chemotactic factors were enhanced significantly after stimulation with 1μg/mL LPS. Specific inhibitors for NF-κB and extracellular signal regulated kinases (ERK), c-Jun N-terminal kinase (JNK), and P38, markedly antagonised LPS-induced adhesion and migration of hDPSCs and also significantly abrogated LPS-induced up-regulation of adhesion molecules and chemotactic factors. In addition, specific inhibitors of SDF-1/CXCR4, AMD3100 significantly diminished LPS-induced migration of hDPSCs.. LPS at specific concentrations can promote cell adhesion and migration in hDPSCs via the NF-κB and MAPK pathways by up-regulating the expression of adhesion molecules and chemotactic factors.. LPS may influence pulp healing through enhancing the adhesion and migration of human dental pulp stem cells when it enters into pulp during pulp exposure or deep caries.

Topics: Adolescent; Adult; Anthracenes; Benzylamines; Butadienes; Cell Adhesion; Cell Adhesion Molecules; Cell Movement; Cells, Cultured; Chemokine CXCL12; Chemotactic Factors; Cyclams; Dental Pulp; Escherichia coli; Extracellular Signal-Regulated MAP Kinases; Heterocyclic Compounds; Humans; Imidazoles; JNK Mitogen-Activated Protein Kinases; Lipopolysaccharides; MAP Kinase Signaling System; NF-kappa B; Nitriles; p38 Mitogen-Activated Protein Kinases; Pyridines; Pyrrolidines; Receptors, CXCR4; Signal Transduction; Stem Cells; Thiocarbamates; Young Adult

Mesenchymal stem cells (MSCs) are able to home and migrate into damaged tissues and are thus, considered an optimal therapeutic strategy for clinical use. We previously demonstrated that higher shear stress (>2 Pa) hindered human MSC (hMSC) migration, whereas lower shear stress (0.2 Pa) induced cell migration through mitogen-activated protein kinase (MAPK) pathways. Here the mechanisms underlying shear stress-induced hMSC migration have been studied further. An MSC monolayer was mechanically wounded and subsequently exposed to low-level shear stress of 0.2 Pa. Image analysis was performed to quantify cell migration speeds under both flow and static conditions. hMSCs along both upstream- and downstream edges of the wound migrated at a similar speed to cover the wounded area under static conditions, whereas shear stress induced cells along the downstream edge of the wound to migrate significantly faster than those along the upstream edge. We also found that shear stress upregulated the secretion of stromal-derived factor-1 (SDF-1), which stimulated its receptor CXCR4 expression in hMSCs until the cells covered the wounded area. A CXCR4 antagonist repressed both cell migration and activation of c-Jun N-terminal kinase (JNK) and p38 MAPK but did not affect extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation. When MAPK activation in upstream- and downstream hMSCs was evaluated separately, ERK1/2 was activated earlier in downstream than in upstream cells. These results indicate that the SDF-1/CXCR4 axis mediates shear stress-induced hMSC migration through JNK and p38 MAPK pathways and that the difference in migration speeds between upstream- and downstream cells may be due to ERK1/2 activation.

Topics: Anthracenes; Benzylamines; Butadienes; Cell Movement; Cell- and Tissue-Based Therapy; Cells, Cultured; Chemokine CXCL12; Cyclams; Enzyme Activation; Enzyme Inhibitors; Extracellular Signal-Regulated MAP Kinases; Heterocyclic Compounds; Humans; Imidazoles; JNK Mitogen-Activated Protein Kinases; MAP Kinase Signaling System; Mesenchymal Stem Cells; Mitogen-Activated Protein Kinases; Nitriles; p38 Mitogen-Activated Protein Kinases; Pyridines; Receptors, CXCR4; Stress, Mechanical; Wound Healing

The chemokine receptor CXCR4, which binds the chemokine stromal cell-derived factor 1, has been reported to be involved in the chemotaxis of inflammatory cells. In addition, AMD3100, an antagonist of CXCR4, has been reported to be an attractive drug candidate for therapeutic intervention in several disorders in which CXCR4 is critically involved. However, little is known about the therapeutic value of AMD3100 in the treatment of pulmonary fibrosis. In this study, we examined the effects of AMD3100 on a murine bleomycin-induced pulmonary fibrosis model. Concurrent administration of AMD3100 and bleomycin apparently attenuated bleomycin-induced pulmonary inflammation. In this process, an inhibition of neutrophil recruitment at early stage followed by the decrease of other inflammatory cell recruitment in the lung were observed. In addition, it also inhibited the expression of cytokines, including MCP-1, MIP-2, MIP-1alpha, and TGF-beta. In contrast, when AMD3100 was administered following bleomycin treatment, the bleomycin-induced lung inflammation progressed and resulted in severe pulmonary fibrosis. In this process, an increase of inflammatory cell recruitment, an up-regulation of lung MCP-1 and TGF-beta, and a remarkable activation of p44/42 MAPK in neutrophils were observed. U0126, an inhibitor of p44/42 MAPK, significantly abolished these effects. Thus, AMD3100 has dual effect on bleomycin-induced pulmonary fibrosis. Difference of inflammatory cell recruitment and activation might be associated with the dual effect of AMD3100 on bleomycin-induced pulmonary fibrosis.

Topics: Animals; Anti-HIV Agents; Benzylamines; Bleomycin; Bronchoalveolar Lavage Fluid; Butadienes; Cyclams; Cytokines; Female; Heterocyclic Compounds; Mice; Mice, Inbred C57BL; Mitogen-Activated Protein Kinase 1; Mitogen-Activated Protein Kinase 3; Neutrophils; Nitriles; Pneumonia; Pulmonary Fibrosis; Receptors, CXCR4

To evaluate the expression of C-X-C motif chemokine receptor 4 (CXCR4) and its signaling cascades, which were previously identified as a key factor for cancer cell progression and metastasis, in cholangiocarcinoma cell lines.. The expression of CXCR4 and its signaling cascades were determined in the cholangiocarcinoma cell lines (RMCCA1 and KKU100) by Western blotting. The invasion assays and the detection of actin polymerization were tested in these cholangiocarcinoma cells treated with CXC chemokine ligand -12 (CXCL12).. Expression of CXCR4 was detected in both cholangiocarcinoma cell lines and activation of CXCR4 with CXCL12 triggered the signaling via the extracellular signal-regulated kinase-1/2 (ERK1/2) and phosphoinositide 3-kinase (PI3K) and induction of cholangiocarcinoma cell invasion, and displayed high levels of actin polymerization. Addition of CXCR4 inhibitor (AMD3100) abrogated CXCL12-induced phosphorylation of MEK1/2 and Akt in these cells. Moreover, treatment with MEK1/2 inhibitor (U0126) or PI3K inhibitor (LY294002) also attenuated the effect of CXCL12-induced cholangiocarcinoma cell invasion.. These results indicated that the activation of CXCR4 and its signaling pathways (MEK1/2 and Akt) are essential for CXCL12-induced cholangiocarcinoma cell invasion. This rises Implications on a potential role for the inhibition of CXCR4 or its signal cascades in the treatment of cholangiocarcinoma.

Topics: Benzylamines; Bile Duct Neoplasms; Bile Ducts, Intrahepatic; Butadienes; Cell Line, Tumor; Chemokine CXCL12; Chemokines, CXC; Cholangiocarcinoma; Chromones; Cyclams; Cytoskeleton; Enzyme Inhibitors; Gene Expression Regulation, Neoplastic; Heterocyclic Compounds; Humans; MAP Kinase Kinase 1; MAP Kinase Kinase 2; Morpholines; Neoplasm Invasiveness; Nitriles; Oncogene Protein v-akt; Phosphatidylinositol 3-Kinases; Phosphoinositide-3 Kinase Inhibitors; Receptors, CXCR4; Signal Transduction