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Evans Blue Dye (Evan + blue_dye)
Selected AbstractsRole of interleukin-18 in the development of acute pulmonary injury induced by intestinal ischemia/reperfusion and its possible mechanismJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 2 2007Yong-jie Yang Abstract Background and Aims:, Lung injury is an important target for the systemic inflammatory response associated with intestinal ischemia/reperfusion (I/R). In the present study, the role of interleukin (IL)-18 in the development of acute pulmonary injury induced by intestinal I/R and its possible mechanism in relation to the increased activity of inducible nitric oxide synthase and tumor necrosis factor (TNF)-, were investigated. Methods:, Mice were randomly divided into three groups: normal control group without operation; sham group with sham operation; and I/R group in which mice underwent superior mesenteric artery occlusion for 30 min followed by reperfusion for 3 h. Each group received pretreatment with exogenous IL-18, anti-IL-18 neutralizing antibody or L-NIL, the selective inhibitor of inducible nitric oxide synthase, 30 min before ischemia. The expression of TNF-, was detected by reverse transcription-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA). Lung injury was evaluated by means of Evans blue dye (EBD) concentration, myeloperoxidase (MPO) activity and morphological analysis. Results:, The experimental results showed that both in the sham-operated and I/R groups of animals, pretreatment with exogenous IL-18 clearly enhanced pulmonary MPO activity, microvascular leakage and the expression of TNF-, mRNA and protein. In contrast, IL-18 did not increase the TNF-, level and degree of lung injury, although it clearly enhanced the pulmonary MPO activity in normal animals. Meanwhile, IL-18 antibody given prior to ischemia led to a reduction in the sequestration of neutrophils, extravasation of EBD and downregulation of the serum level of TNF-, in the I/R group of animals. In addition, selective inhibition of inducible nitric oxide synthase (iNOS) that inhibited plasma extravasation and pulmonary injury without affecting the MPO activity could be demonstrated in all treated animals. Conclusions:, These data suggested a role of IL-18 in the activation and sequestration of neutrophils in lungs. Our results were consistent with the hypothesis that increased sequestration of neutrophils and microvascular leakage might, respectively, relate to the increased IL-18 level and the elevation of TNF-,/iNOS activity, and these two aspects might synergically contribute to intestinal I/R-induced pulmonary dysfunction. [source] Use of evans blue dye to compare limb muscles in exercised young and old mdx miceMUSCLE AND NERVE, Issue 4 2010Christine I. Wooddell PhD Abstract Evans blue dye (EBD) is used to mark damaged and permeable muscle fibers in mouse models of muscular dystrophy and as an endpoint in therapeutic trials. We counted EBD-positive muscle fibers and extracted EBD from muscles sampled throughout the hindlimbs in young adult and old mdx mice to determine if the natural variability in morphology would allow measurement of a functional improvement in one limb compared to the contralateral limb. Following one bout of rotarod or treadmill exercise that greatly increased serum creatine kinase levels, the number of EBD+ muscle fibers in 12,19-month-old mdx mice increased 3-fold, EBD in the muscles increased, and, importantly, contralateral pairs of muscles contained similar amounts of EBD. In contrast, the intra- and interlimb amounts of EBD in 2,7-month-old mdx mice were much too variable. A therapeutic effect can more readily be measured in old mdx mice. These results will be useful in the design of therapy protocols using the mdx mouse. Muscle Nerve, 2010 [source] Effect of quercetin on tachykinin-induced plasma extravasation in rat urinary bladderPHYTOTHERAPY RESEARCH, Issue 5 2001Paulo R. Wille Abstract The effect of quercetin on substance P-induced plasma extravasation in rat urinary bladder and its modulation by endogenous peptidases in conscious rats was studied. Plasma protein extravasation (PE) was assayed by measurement of extravasated Evans blue dye (,g/g dry tissue). Intravenous injection of substance P (SP, 10 nmol/kg) significantly increased PE in the urinary bladder. PE evoked by SP was increased significantly by quercetin (20,mg/kg, p.o.) pretreatment in the urinary bladder (73.5 ± 4.9 to 152.2,±,9.9). Pretreatment with captopril, an angiotensin-converting enzyme (ACE) inhibitor (10 nmol/kg, i.v.), or with phosphoramidon, a neutral endopeptidase (NEP) inhibitor (2.5,,mol/kg, i.v.) also potentiated the SP-induced PE in urinary bladder, 286.2,±,20.4 and 323.3,±,34.0, respectively. Quercetin did not show any effect on neurokinin-A (NKA, 10 nmol/kg, i.v.) -induced plasma extravasation. The present study demonstrates that quercetin potentiates the PE induced by substance P in the urinary bladder. These effects suggest that this flavonoid might cause inhibition of NEP and/or ACE. Copyright © 2001 John Wiley & Sons, Ltd. [source] Glial-derived neurotrophic factor regulates intestinal epithelial barrier function and inflammation and is therapeutic for murine colitis,THE JOURNAL OF PATHOLOGY, Issue 2 2010Dei Kui Zhang Abstract Although enteric glial cells (EGCs) have been demonstrated to play a key role in maintaining intestinal epithelial barrier integrity, it is not known how EGCs regulate this integrity. We therefore hypothesized that glial-derived neurotrophic factor (GDNF) produced by EGCs might be involved in this regulation. Here we investigated the role of GDNF in regulating epithelial barrier function in vivo. Recombinant adenoviral vectors encoding GDNF (Ad-GDNF) were administered intracolonically in experimental colitis induced by dextran sulphate sodium (DSS). The disease activity index (DAI) and histological score were measured. Epithelial permeability was assayed using Evans blue dye. The anti-apoptotic potency of GDNF in vivo was evaluated. The expression of tumour necrosis factor- , (TNF- ,), interleukin-1, (IL-1,), and myeloperoxidase (MPO) activity were measured by ELISA assay and/or RT-PCR. The expression of ZO-1, Akt, caspase-3, and NF- ,B p65 was analysed by western blot assay. Our results showed that GDNF resulted in a significant reduction in enhanced permeability, inhibited MPO activity, IL-1, and TNF- , expression, and increased ZO-1 and Akt expression. Moreover, GDNF strongly prevented apoptosis in vivo and significantly ameliorated experimental colitis. Our findings indicate that GDNF participates directly in restoring epithelial barrier function in vivo via reduction of increased epithelial permeability and inhibition of mucosal inflammatory response, and is efficacious in DSS-induced colitis. These findings support the notion that EGCs are able to regulate intestinal epithelial barrier integrity indirectly via their release of GDNF in vivo. GDNF is namely an important mediator of the cross-talk between EGCs and mucosal epithelial cells. GDNF may be a useful therapeutic approach to the treatment of inflammatory bowel disease. Copyright © 2010 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [source] Blood,brain barrier breakdown and repair by Src after thrombin-induced injuryANNALS OF NEUROLOGY, Issue 4 2010Da-Zhi Liu PhD Objective Thrombin mediates the life-threatening cerebral edema that occurs after intracerebral hemorrhage. Therefore, we examined the mechanisms of thrombin-induced injury to the blood,brain barrier (BBB) and subsequent mechanisms of BBB repair. Methods Intracerebroventricular injection of thrombin (20U) was used to model intraventricular hemorrhage in adult rats. Results Thrombin reduced brain microvascular endothelial cell (BMVEC) and perivascular astrocyte immunoreactivity,indicating either cell injury or death,and functionally disrupted the BBB as measured by increased water content and extravasation of sodium fluorescein and Evans blue dyes 24 hours later. Administration of nonspecific Src family kinase inhibitor (PP2) immediately after thrombin injections blocked brain edema and BBB disruption. At 7 to 14 days after thrombin injections, newborn endothelial cells and astrocytes were observed around cerebral vessels at the time when BBB permeability and cerebral water content resolved. Delayed administration of PP2 on days 2 through 6 after thrombin injections prevented resolution of the edema and abnormal BBB permeability. Interpretation Thrombin, via its protease-activated receptors, is postulated to activate Src kinase phosphorylation of molecules that acutely injure the BBB and produce edema. Thus, acute administration of Src antagonists blocks edema. In contrast, Src blockade for 2 to 6 days after thrombin injections is postulated to prevent resolution of edema and abnormal BBB permeability in part because Src kinase proto-oncogene members stimulate proliferation of newborn BMVECs and perivascular astrocytes in the neurovascular niche that repair the damaged BBB. Thus, Src kinases not only mediate acute BBB injury but also mediate chronic BBB repair after thrombin-induced injury. ANN NEUROL 2010;67:526,533 [source] | ||||||||||