Correlation between DNA methylation and Thymic Stromal Lymphopoietin expression in asthmatic airway epithelial cells.

BACKGROUND: The overexpression of TSLP and DNA methylation in asthma were both risk factors the relationship was not clear. OBJECTIVE: This study aimed to investigate the relationship between methylation status of TSLP promoter and mRNA/protein expression in asthmatic airway epithelial cells. METHODS: Human bronchial epithelial cells were cultured in vitro and divided into: Control group, treated with PBS, model group, sensitized with LPS (10 µg/mL) for 12 h (37 °C, 5% CO2). Other groups were cultured with the pCMV3 plasmid (M + NC/pCMV), pGPH1 plasmid (M + NC/pGPH), DNMT1/pCMV3 plasmid (M + DNMT1/pCMV), and DNMT1/pGPH1 plasmid (M + DNMT1/pGPH) for 48 h. The expression of DNA methyltransferase 1 and TSLP were measured using real-time PCR and western blotting. RESULTS: Compared with the control group, TSLP mRNA (1.00 ± 0.00 vs. 2.82 ± 0.81 vs. 1, P < 0.001) and protein (1.07 ± 0.04 vs. 1.46 ± 0.11, P < 0.01) were significantly greater, and the methylation of promoter was lower (92.75 ± 1.26 vs. 58.57 ± 3.34, P < 0.05) in the model group. Compared with the model group, TSLP mRNA (2.82 ± 0.81 vs. 1.17 ± 0.10, P < 0.001) decreased, but TSLP promoter methylation increased (58.57 ± 3.34 vs. 92.58 ± 7.30, P < 0.05) in M + DNMT1/pCMV. TSLP mRNA and protein were higher (2.82 ± 0.81 vs. 5.32 ± 0.21, P < 0.001; 1.46 ± 0.11 vs. 1.94 ± 0.11, respectively, P < 0.01), TSLP promoter methylation was lower (58.57 ± 3.34 vs. 33.57 ± 4.29, P < 0.05) in M + DNMT1/pGPH. CONCLUSIONS: Overexpression of TSLP in asthmatic airway epithelial cells may be regulated by DNA demethylation.

Sphingosine kinase 1/sphingosine 1-phosphate signalling pathway as a potential therapeutic target of pulmonary hypertension.

Pulmonary hypertension is characterized by extensive vascular remodelling, leading to increased pulmonary vascular resistance and eventual death due to right heart failure. The pathogenesis of pulmonary hypertension involves vascular endothelial dysfunction and disordered vascular smooth muscle cell (VSMC) proliferation and migration, but the exact processes remain unknown. Sphingosine 1-phosphate (S1P) is a bioactive lysophospholipid involved in a wide spectrum of biological processes. S1P has been shown to regulate VSMC proliferation and migration and vascular tension via a family of five S1P G-protein-coupled receptors (S1P1-SIP5). S1P has been shown to have both a vasoconstrictive and vasodilating effect. The S1P receptors S1P1 and S1P3 promote, while S1P2 inhibits VSMC proliferation and migration in vitro in response to S1P. Moreover, it has been reported recently that sphingosine kinase 1 and S1P2 inhibitors might be useful therapeutic agents in the treatment of empirical pulmonary hypertension. The sphingosine kinase 1/S1P signalling pathways may play a role in the pathogenesis of pulmonary hypertension. Modulation of this pathway may offer novel therapeutic strategies.

Transfer of the IL-37b gene elicits anti-tumor responses in mice bearing 4T1 breast cancer.

AIM: IL-37b has shown anti-cancer activities in addition to its anti-inflammatory properties. In this study, we investigated the effects of IL-37b on breast carcinoma growth in mice and to determine the involvement of T cell activation in the effects. METHODS: IL-37b gene was transferred into mouse breast carcinoma cell line 4T1 (4T1-IL37b cells), the expression of secretory IL-37b by the cells was detected, and the effects of IL-37b expression on the cell proliferation in vitro was evaluated. After injection of 4T1 cells or 4T1-IL37b cells into immunocompetent BALB/c mice, immunodeficient BALB/c nude mice and NOD-SCID mice, the tumor growth and survival rate were measured. The proliferation of T cells in vitro was also detected. RESULTS: IL-37b was detected in the supernatants of 4T1-IL37b cells with a concentration of 12.02 ± 0.875 ng/mL. IL-37b expression did not affect 4T1 cell proliferation in vitro. BALB/c mice inoculated with 4T1-IL37b cells showed significant retardation of tumor growth. BALB/c mice inoculated with both 4T1 cells and mitomycin C-treated 4T1-IL37b cells also showed significant retardation of tumor growth. But the anti-cancer activity of IL-37b was abrogated in BALB/c nude mice and NOD-SCID mice inoculated with 4T1-IL37b cells. Recombinant IL-37b slightly promoted CD4(+) T cell proliferation without affecting CD8(+) T cell proliferation. CONCLUSION: IL-37b exerts anti-4T1 breast carcinoma effects in vivo by modulating the tumor microenvironment and influencing T cell activation.

RAGE signaling significantly impacts tumorigenesis and hepatic tumor growth in murine models of colorectal carcinoma.

BACKGROUND: The receptor for advanced glycation end-products (RAGE) is a cell surface receptor implicated in tumor cell proliferation and migration. We hypothesized that RAGE signaling impacts tumorigenesis and metastatic tumor growth in murine models of colorectal carcinoma. MATERIALS AND METHODS: Tumorigenesis: Apc (1638N/+) mice were crossed with Rage (-/-) mice in the C57BL/6 background to generate Apc (1638N/+)/Rage (-/-) mice. Metastasis: BALB/c mice underwent portal vein injection with CT26 cells (syngeneic) and received daily soluble (s)RAGE or vehicle. Rage (-/-) mice and Rage (+/+) controls underwent portal vein injection with MC38 cells (syngeneic). Rage (+/+) mice underwent portal vein injection with MC38 cells after stable transfection with full-length RAGE or mock transfection control. RESULTS: Tumorigenesis: Apc (1638N/+)/Rage (-/-) mice had reduced tumor incidence, size, and histopathologic grade. Metastasis: Pharmacological blockade of RAGE with sRAGE or genetic deletion of Rage reduced hepatic tumor incidence, nodules, and burden. Gain of function by transfection with full-length RAGE increased hepatic tumor burden compared to vector control MC38 cells. CONCLUSION: RAGE signaling plays an important role in tumorigenesis and hepatic tumor growth in murine models of colorectal carcinoma. Further work is needed to target the ligand-RAGE axis for possible prophylaxis and treatment of primary and metastatic colorectal carcinoma.

Simultaneous removal of coexistent heavy metals from simulated urban stormwater using four sorbents: a porous iron sorbent and its mixtures with zeolite and crystal gravel.

The selectivity sequence and removal of coexistent heavy metals (namely As, Cd, Cr, Cu, Ni and Zn) in synthetic urban stormwater runoff were investigated by adsorption onto a porous iron sorbent (namely P1) and its mixtures with zeolite and crystal gravel, respectively (namely P2, P3, and P4). A batch method was employed to simulate the sorption processes. The geochemical model PHREEQC was used to calculate the metals' species and saturation data for elucidating the sorption data. The equilibrium data demonstrated a good fit with the Freundlich model and showed affinity in the orders: Cd>Zn>Ni>Cu>As>Cr (sorbents P1, P3 and P4) and Cd>Zn>Ni>As>Cu>Cr (sorbent P2). In addition to this, Calculated Distribution Coefficient (K(d)) values were used to compare the overall heavy metal removal efficiencies of the sorbents, which, in decreasing order, was found to be P4>P1>P2>P3. In comparing these four commercial sorbents, sorbent P4 represents a promising material for treatment of urban stormwater runoff containing mixed heavy metals.

[Determination of trace elements of Gentiana macrophlla and Gentiana straminea by microwave digestion-FAAS].

An acid-assisted microwave digestion procedure is optimized for the determination of trace elements in traditional Chinese medicine by the use of flame atomic absorption spectrometric (FAAS) techniques. Microwave-assisted digestion has the advantages of reduced time for sample dissolution, fewer possibilities for technical errors caused by spilling of hot digestion solutions, use of less chemicals, and lower losses of volatile metals. In addition, modern microwave ovens are safer and simpler and provide more controlled and reproducible conditions than hot plate or block digesters. Flame atomic absorption spectrometry (FAAS) is more commonly applied techniques in the de termination of trace elements. The accurate measurement of trace elements concentrations in samples of traditional Chinese medicine is an important goal in research for medical effects of traditional Chinese medicine. The purpose of this study was to determine the contents of the trace elements in Gentiana macrophlla and Gentiana straminea. In order to identify the accuracy of the procedure, the operating conditions was selected before the determination of trace elements. In order to gauge the effectiveness of digestion, the selection of digestion conditions of the technique was undertaken. The results showed HNO3-H2O2 (5 : 1) as a microwave digestion agent with suitable temperature and time was optimum choice in the digestion procedure. Analysis limits were also selected according to the low detection limits and the good precision. They were Fe(248.3 nm), Mn (279.5 nm), Ni (232.0 nm), Cu(324. 8 nm), Zn (2.139 nm), Ca (422.7 nm), Mg (285.2 nm) and Cr (357.9 nm), respectively. The working curves were obtained by using multi-elemental standard solutions and line relation was good. Under the selected conditions, the contents of trace elements Fe, Mn, Ni, Cu, Zn, Ca, Mg and Cr in Gentiana macrophlla and Gentiana straminea were directly determined using working curve methods. The relative standard deviations (RSD) and recovery of the method have been undertaken to obtain reliable results for trace element determinations. The recovery rates obtained by standard addition method were between 88.1%-114.5%, and the relative standard deviations (RSD) were lower than 3.12% after optimization of the operating conditions. These figures showed that the method gave good recoveries and accuracy. The analytical results indicated that there were comparatively rich elements in Gentiana macrophila and Gentiana straminea, such as Ca, Mg, Fe, Mn and Zn, especially the concentration of Ca and Mg. However, concentrations of Ni and Cr in Gentiana macrophlla and Gentiana straminea were very low, especially the concentration of Ni. The worse value obtained for Ni was probably due to its inhomogeneous distribution and very low concentration in Gentiana macrophlla and Gentiana straminea. In addition, a comparison of the contents of trace elements between Gentiana macrophlla and Gentiana straminea indicated that Gentiana macrophlla was rich in the trace elements such as Fe, Mn, Ni and Mg, and Gentiana straminea was rich in the trace elements such as Zn, Cu, Ca and Cr. The result will provide scientific datas for discussing the relationship between the contents of these elements in Gentiana macrophlla and Gentiana straminea and the medical effects. Furthermore, our study provides new scientific foundation for further study and general application of Gentiana macrophlla and Gentiana straminea.