Visfatin Promotes Monocyte Adhesion by Upregulating ICAM-1 and VCAM-1 Expression in Endothelial Cells via Activation of p38-PI3K-Akt Signaling and Subsequent ROS Production and IKK/NF-κB Activation.

BACKGROUND/AIMS: Visfatin is known to act as a mediator in several metabolic disorders, such as obesity, diabetes, and cardiovascular diseases. This study aimed to investigate the effect of visfatin on the adhesion of THP-1 monocytes to human vascular endothelial cells and the underlying mechanism. METHODS: Monocytes adhesion to endothelial cells was determined by using fluorescence-labeled monocytes. ICAM-1 and VCAM-1 expression in endothelial cells were measured by western blotting. Production of reactive oxygen species (ROS) was measured by using a fluorescent dye. The amounts of nuclear factor-kappa B (NF-κB) and phosphorylation of inhibitory factor of NF-κB (IκB) were determined by using western blot analysis. The translocation of NF-κB from the cytoplasm to the nucleus was determined by using immunofluorescence. RESULTS: Here we showed that visfatin significantly caused the upregulation of intercellular cell adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in endothelial cells, as well as enhanced monocyte adhesion to endothelial cells. Moreover, we found that inhibition of PI3K, Akt, and p38 MAPK activation significantly prevented visfatin-enhanced expression of ICAM-1 and VCAM-1 and monocyte adhesion to endothelial cells. Visfatin enhanced ROS production and IKK/NF-кB activation and then led to upregulation of ICAM-1 and VCAM-1 and enhanced monocyte adhesion to endothelial cells. These effects were also p38/PI3K/Akt-dependent. CONCLUSION: These results demonstrated that visfatin promoted monocyte-endothelial cell adhesion by increasing ICAM-1 and VCAM-1 expression via the activation of p38/PI3K/Akt signaling and downstream ROS production and IKK/NF-кB activation.

RASSF8 downregulation promotes lymphangiogenesis and metastasis in esophageal squamous cell carcinoma.

Lymphatic vessels are the major routes of human esophageal squamous cell carcinoma (ESCC) metastasis. Tumor cells secrete pro-lymphangiogenic factors to induce new lymphatic vessels, promoting lymph node metastasis. In this study, we show that RAS association domain family 8 (RASSF8) expression in ESCC clinical samples was inversely correlated with lymph node metastasis and patients survival. Tumor cells with low RASSF8 expression had higher apparent migratory ability, and promoted and lymphangiogenesis both in vitro and in vivo. RASSF8 downregulation enhanced VEGF-C expression and caused subcellular redistribution of p65 in ESCC. Our results show that RASSF8 acts as a tumor suppressor in ESCC and is a potential therapeutic target for preventing lymph node metastasis.

Glucose increases interleukin-12 gene expression and production in stimulated peripheral blood mononuclear cells of type 2 diabetes patients.

BACKGROUND: Lipopolysaccharide (LPS)-stimulated peripheral blood mononuclear cells (PBMCs) of type 2 diabetes patients produce more interleukin (IL)-12 under glucose treatment. The aim of this study was to determine whether increased IL-12 response in hyperglycemic LPS-stimulated PBMCs is due to increased gene expression or osmolarity. METHODS: LPS-stimulated PBMCs of 13 type 2 diabetes patients and 8 healthy controls were used for culture in the presence or absence of glucose or mannitol for 24 h. The IL-12 gene expressions of PBMCs and IL-12 protein levels in supernatants were evaluated. RESULTS: After 24 h, the stimulated PBMCs of diabetes patients expressed more IL-12 mRNA and produced more IL-12 protein following glucose treatment than those without glucose treatment and with mannitol treatment. Stimulated PBMCs of controls did not express more IL-12 mRNA and produce more IL-12 protein following glucose treatment than those without glucose treatment and with mannitol treatment. CONCLUSIONS: Glucose increases the IL-12 production in stimulated PBMCs of diabetes patients through increased IL-12 gene expression.

Phase transformation of molecular beam epitaxy-grown nanometer-thick Gd2O3 and Y2O3 on GaN.

High quality nanometer-thick Gd2O3 and Y2O3 (rare-earth oxide, R2O3) films have been epitaxially grown on GaN (0001) substrate by molecular beam epitaxy (MBE). The R2O3 epi-layers exhibit remarkable thermal stability at 1100 °C, uniformity, and highly structural perfection. Structural investigation was carried out by in situ reflection high energy electron diffraction (RHEED) and ex-situ X-ray diffraction (XRD) with synchrotron radiation. In the initial stage of epitaxial growth, the R2O3 layers have a hexagonal phase with the epitaxial relationship of R2O3 (0001)(H)<1120>(H)//GaN(0001)(H)<1120>(H). With the increase in R2O3 film thickness, the structure of the R2O3 films changes from single domain hexagonal phase to monoclinic phase with six different rotational domains, following the R2O3 (201)(M)[020](M)//GaN(0001)(H)<1120>(H) orientational relationship. The structural details and fingerprints of hexagonal and monoclinic phase Gd2O3 films have also been examined by using electron energy loss spectroscopy (EELS). Approximate 3-4 nm is the critical thickness for the structural phase transition depending on the composing rare earth element.

[Effects of rhBMP-7 on osteoblast differentiation of murine bone marrow mesenchymal stem cells in vitro].

AIM: To study the effects of recombinant human bone morphogenetic protein-7 (rhBMP-7) on osteoblast differentiation of murine bone marrow mesenchymal stem cells (BMSCs). METHODS: The BMSCs were collected from murine bone marrow by density gradient centrifugation. Cells were adherent cultured and expanded in vitro. RhBMP-7 was added into the culture medium of the 3rd passage BMSCs. Five days later, we performed alkaline phosphatase (ALP) staining and detected ALP activity and osteocalcin (OC) content. Osteoblast differentiation marker gene including OC and collage I (Col-I) were assayed by RT-PCR. Total protein was isolated and the secretion of Col-I in the cells was measured by Western blotting. RESULTS: The staining intensity of ALP in the group with rhBMP-7 was stronger than that in the negative control group. ALP activity and OC content of rhBMP-7 group were obviously higher than that of the negative control group. The mRNA of OC and Col-I and the protein of Col-I were highly expressed in the group induced by rhBMP-7. CONCLUSION: RhBMP-7 can induce murine BMSCs to differentiate into osteoblast in vitro.

High interleukin-12 production from stimulated peripheral blood mononuclear cells of type 2 diabetes patients.

UNLABELLED: Sugar control is important in patients with sepsis. Interleukin (IL)-12 induces the polarization of CD4(+) T cells to the T helper 1 (Th1) phenotype. Regulatory T (T(reg)) cells are important in immunity and disease. The aim of this work is to determine whether hyperglycemia or insulin alters IL-12 response in peripheral mononuclear cells (PBMCs). METHODS: The PBMCs from 15 type 2 diabetes mellitus (DM) patients and 13 healthy controls were used for cell analysis and culture with or without treatment by glucose and insulin or stimulation by lipopolysaccharide (LPS) for 1, 2, and 3 days. RESULTS: The IL-12 level in the supernatant of LPS-stimulated PBMCs in the DM patients was significantly higher than that of healthy controls from day 1 to day 3. Kinetic IL-12 responses of LPS-stimulated PBMCs in the DM patients from day 1 to day 3 were significantly higher than that in healthy controls. The LPS-stimulated PBMCs under glucose treatment produced more IL-12 in DM patients but this did not happen in healthy controls. In DM patients, insulin could suppress IL-12 production from stimulated PBMCs but not with additional glucose treatment. CONCLUSION: The PBMCs of LPS-treated DM patients produced more IL-12 than that of LPS-treated healthy controls did. Hyperglycemia influenced IL-12 response from PBMCs in DM patients to some degree during infection.

Comparison of plasma interferon-gamma and antigen 60 immunoglobulin G in diagnosing pulmonary Mycobacterium tuberculosis infection.

BACKGROUND: An elevated interferon-gamma (IFN-gamma) level has been reported in the plasma of patients with pulmonary tuberculosis. Serologic diagnosis of tuberculosis using Antigen 60 immunoglobulin G (A60 IgG) is a well-known diagnostic approach. This study evaluated plasma IFN-y compared to A60 IgG in diagnosing Mycobacterium tuberculosis. METHODS: This study recruited 65 patients with tuberculosis and 59 controls. The plasma levels of A60 IgG and IFN-gamma were measured using enzyme-linked immunosorbent assay kits. RESULTS: The cutoff values of IFN-gamma and A60 IgG tests were set at 0.137 pg/ml and 261.2 units. The sensitivity and specificity of the IFN-gamma test were 27.7% and 91.5%. The positive and negative predictive values of the IFN-gamma test were 53.4% and 78.3%. Moreover, the sensitivity and specificity of the A60 IgG test were 53.8% and 67.8%. The positive and negative predictive values of the A60 IgG test were 37.0% and 80.7%. Finally, the sensitivity and specificity of the combined A60 IgG and IFN-gamma tests were 64.6% and 62.7%. The positive and negative predictive values of the combined A60 IgG and IFN-gamma tests were 37.8% and 83.4%. CONCLUSIONS: The combined tests did not achieve significant improvement in disease prediction. The A60 IgG test and IFN-gamma test had similar diagnostic value in pulmonary Mycobacterium tuberculosis infection.