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Marked Upregulation (marked + upregulation)
Selected AbstractsBrain Endothelial Adhesion Molecule Expression in Experimental ColitisMICROCIRCULATION, Issue 2 2001MIQUEL SANS ABSTRACT Objectives: 1) To determine if endothelial expression of adhesion molecules involved in leukocyte recruitment is increased in the brain and other organs in four different models of experimental colitis, and 2) to investigate whether leukocyte infiltration occurs in the brain of colitic animals. Methods: Endothelial vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) expression was quantified, using the dual radiolabeled antibody technique in rats with trinitrobenzenesulfonic acid (TNBS)-induced colitis, in mice with dextran sulfate sodium (DSS)-induced colitis, in SCID mice reconstituted with CD45RBhigh T-cells, and in IL-10,/, mice. Leukocyte infiltration in the brain of TNBS-induced colitic rats was assessed by myeloperoxidase activity and immunohistochemical staining with anti-CD45 monoclonal antibody. Results: Marked upregulation of brain endothelial VCAM-1 (2- to 5.5-fold) was consistently found in colitic animals in the four models studied. Brain VCAM-1 strongly correlated with colon VCAM-1 and colon weight. By contrast, upregulation of brain ICAM-1 in colitic animals was only observed in the CD45RBhigh transfer (3-fold) and the TNBS-induced (1.5-fold models). Heart and muscle VCAM-1 and ICAM-1 were not upregulated in colitic animals in the majority of models studied. There was no leukocyte infiltration into the brain of TNBS-induced colitic rats. Conclusions: Our study demonstrates a marked and specific upregulation of endothelial VCAM-1 in the brain of colitic animals. This activation of cerebral endothelial cells was not associated with an infiltration of leukocytes into brain tissue. [source] The Pseudomonas aeruginosa quinolone signal (PQS) has an iron-chelating activityENVIRONMENTAL MICROBIOLOGY, Issue 8 2006Florian Bredenbruch Summary Virulence factor production and the development of biofilms in Pseudomonas aeruginosa have been shown to be regulated by two hierarchically organized quorum-sensing systems activated by two types of small acyl-homoserine lactone signal molecules. Recently, a third type of bacterial signal molecule, the Pseudomonas quinolone signal (PQS), has been identified, which positively regulates a subset of genes dependent on the quorum-sensing systems. However, the molecular mechanism underlying PQS signalling has remained poorly understood. In this study the global transcriptional profile of P. aeruginosa in response to PQS revealed a marked upregulation of genes belonging to the tightly interdependent functional groups of the iron acquisition and the oxidative stress response. Remarkably, most of the differentially regulated genes, as well as the induction of rhlR, could be traced back to an iron-chelating effect of PQS. Our results amount to the elucidation of how PQS affects P. aeruginosa and have important implications for the understanding of the complex regulatory circuits involved in P. aeruginosa gene regulation. [source] Tumor-stromal crosstalk in invasion of oral squamous cell carcinoma: a pivotal role of CCL7INTERNATIONAL JOURNAL OF CANCER, Issue 2 2010Da-Woon Jung Abstract Recent studies have shown that stromal fibroblasts have a more profound influence on the initiation and progression of carcinoma than was previously appreciated. This study aimed at investigating the reciprocal relationship between cancer cells and their associated fibroblasts at both the molecular and cellular level in oral squamous cell carcinoma (OSCC). To identify key molecular regulators expressed by carcinoma-associated fibroblasts (CAF) that promote cancer cell invasion, microarrays were performed by comparing cocultured OSCC cells and CAF with monoculture controls. Microarray and real-time PCR analysis identified marked upregulation of the chemokine (C-C motif) ligand 7 (CCL7) in cocultured CAF. ELISA showed an elevated level of CCL7 secretion from CAF stimulated by coculture with OSCC cells. CCL7 promoted the invasion and migration of OSCC cells, and the invasiveness was inhibited by treatment with CCL7 neutralizing antibody. OSCC cells were shown to express CCR1, CCR2 and CCR3, receptors for CCL7, by RT-PCR. In addition, treatment with anti-CCR1 or anti-CCR3 antibody inhibited CCL7-induced OSCC cell migration, implicating that CCL7 promotes cancer cell migration through CCR1 and CCR3 on OSCC cells. Cytokine antibody array analysis of the supernatant from OSCC cell culture revealed that interleukin-1, was an inducer of CCL7 secretion by CAF. This study confirms the reciprocal relationship of the molecular crosstalk regulating the invasion of OSCC and describes new potential targets for future therapy. [source] Characterization and astrocytic modulation of system L transporters in brain microvasculature endothelial cellsCELL BIOCHEMISTRY AND FUNCTION, Issue 3 2008Yadollah Omidi Abstract Brain trafficking of amino acids is mainly mediated by amino acids transport machineries of the blood,brain barrier (BBB), where astrocytes play a key maintenance role. However, little is known about astrocytes impacts on such transport systems, in particular system L that consists of large and small neutral amino acids (NAAs) transporters, that is, LAT1/4F2hc and LAT2/4F2hc, respectively. In the current investigation, functionality and expression of system L were studied in the immortalized mouse brain microvascular endothelial b.End3 cells cocultured with astrocytes or treated with astrocyte-conditioned media (ACM). LAT2/4F2hc mediated luminal uptake of L -phenylalanine and L -leucine resulted in significantly decreased affinity of system L in b.End3 cells treated with ACM, while LAT2/4F2hc mediated luminal uptake of L -alanine remained unchanged. Gene expression analysis revealed marked upregulation of LAT1 and 4F2hc, but downregulation of LAT2 in b.End3 cells cultured with ACM. The basal to apical transport of L -phenylalanine and L -alanine appeared to be significantly greater than that of the apical to basal direction in b.End3 cells indicating an efflux functionality of system L. No marked influence was observed for transport of L -phenylalanine in b.End3 cells cocultured with astrocytes, while a slight decrease was seen for L -alanine in the basal to apical direction. Based on our findings, we propose that system L functions as influx and/or efflux transport machinery displaying a greater propensity for the outward transport of large and small NAAs. Astrocytes appeared to modulate the transcriptic expression and uptake functionalities of system L, but not the transport activities. Copyright © 2008 John Wiley & Sons, Ltd. [source] | |||||||||||||