Marked Activation (marked + activation)

Distribution by Scientific Domains


Selected Abstracts


Acute experimental colitis and human chronic inflammatory diseases share expression of inflammation-related genes with conserved Ets2 binding sites

INFLAMMATORY BOWEL DISEASES, Issue 2 2009
Tineke C.T.M. van der Pouw Kraan PhD
Abstract Background: Ulcerative colitis (UC) and Crohn's disease (CD) are characterized by chronic inflammation of the gastrointestinal tract, with overlapping clinical characteristics and unknown etiology. We reasoned that in intestinal inflammation the initial activation of the innate immune response fails to resolve, finally resulting in uncontrolled chronic inflammatory bowel disease. Methods: To identify the early inflammatory events in colitis that remain active in human chronic colitis, we analyzed the changes of the colonic transcriptome during acute experimental colitis and compared the outcome with previously published profiles of affected tissues from patients with UC and CD, and as a control for intestinal inflammation in general, tissues from celiac disease patients. Rheumatoid arthritis synovial tissues were included as a nonintestinal inflammatory disease. The expression profiles of each disease were analyzed separately, in which diseased tissues were compared to unaffected tissues from the same anatomical location. Results: Gene ontology analysis of significantly regulated genes revealed a marked activation of immunity and defense processes in all diseases, except celiac disease, where immune activation is less prominent. The control region of upregulated genes contained an increase in Ets2 binding sites in experimental colitis, UC, and rheumatoid arthritis, and were associated with upregulated immune activity. In contrast, upregulated genes in celiac disease harbored the transcription factor binding site GLI, which binds to the Gli family of transcription factors involved in hedgehog signaling, affecting development and morphogenesis. Conclusion: Ets2 may be an important transcription factor driving inflammation in acute as well as chronic inflammatory disease. (Inflamm Bowel Dis 2008) [source]


Opioids and opiates: analgesia with cardiovascular, haemodynamic and immune implications in critical illness

JOURNAL OF INTERNAL MEDICINE, Issue 2 2006
P. E. MOLINA
Abstract. Traumatic injury, surgical interventions and sepsis are amongst some of the clinical conditions that result in marked activation of neuroendocrine and opiate responses aimed at restoring haemodynamic and metabolic homeostasis. The central activation of the neuroendocrine and opiate systems, known collectively as the stress response, is elicited by diverse physical stressor conditions, including ischaemia, glucopenia and inflammation. The role of the hypothalamic,pituitary,adrenal axis and sympathetic nervous system in counterregulation of haemodynamic and metabolic alterations has been studied extensively. However, that of the endogenous opiates/opioid system is still unclear. In addition to activation of the opiate receptor through the endogenous release of opioids, pharmacotherapy with opiate receptor agonists is frequently used for sedation and analgesia of injured, septic and critically ill patients. How this affects the haemodynamic, cardiovascular, metabolic and immune responses is poorly understood. The variety of opiate receptor types, their specificity and ubiquitous location both in the central nervous system and in the periphery adds additional complicating factors to the clear understanding of their contribution to the stress response to the various physical perturbations. This review aims at discussing scientific evidence gathered from preclinical studies on the role of endogenous opioids as well as those administered as pharmacological agents on the host cardiovascular, neuroendocrine, metabolic and immune response mechanisms critical for survival from injury in perspective with clinical observations that provide parallel assessment of relevant outcome measures. When possible, the clinical relevance and corresponding scenarios where this evidence can be integrated into our understanding of the clinical implications of opiate effects will be examined. Overall, the scientific basis to enhance clinical judgment and expectations when using opioid sedation and analgesia in the management of the injured, septic or postsurgical patient will be discussed. [source]


Melatonin inhibits the expression of the inducible isoform of nitric oxide synthase and nuclear factor kappa B activation in rat skeletal muscle

JOURNAL OF PINEAL RESEARCH, Issue 1 2006
Marķa Alonso
Abstract:, This study investigated whether the induction of inducible nitric oxide synthase (iNOS) produced by acute exercise in rat skeletal muscle could be prevented by melatonin and whether iNOS down-regulation was related to inhibition of nuclear factor kappaB (NF- ,B) activation. Male Wistar rats received melatonin i.p. at a dose of 1.0 mg/kg body weight 30 min before being exercised for 60 min on a treadmill at a speed of 25 m/min and a 10% slope. Exercise caused a significant induction of iNOS protein levels and a marked activation of NF- ,B that were significantly prevented in rats treated with melatonin. Exercise also resulted in increased I,B kinase, (IKK,) and phosphorylated I,B, protein levels, whereas I,B, content decreased. These effects were blocked by melatonin administration. The increase in the muscle concentration of thiobarbituric acid reactive substances and in the oxidized/reduced glutathione ratio induced by exercise was partially prevented by melatonin. Our data indicate that melatonin has potent protective effects against damage caused by acute exercise in rat muscle, preventing oxidative stress, NF- ,B activation and iNOS over-expression. These findings support the view that melatonin treatment, by abolishing the IKK/NF- ,B signal transduction pathway, might block the production of noxious mediators involved in the inflammatory process. [source]


Rapamycin inhibits cholangiocyte regeneration by blocking interleukin-6,induced activation of signal transducer and activator of transcription 3 after liver transplantation

LIVER TRANSPLANTATION, Issue 2 2010
Li-Ping Chen
Cholangiocyte proliferation is necessary for biliary recovery from cold ischemia and reperfusion injury (CIRI), but there are few studies on its intracellular mechanism. In this process, the role of rapamycin, a new immunosuppressant used in liver transplantation, is still unknown. In order to determine whether rapamycin can depress cholangiocyte regeneration by inhibiting signal transducer and activator of transcription 3 (STAT3) activation, rapamycin (0.05 mg/kg) was administered to rats for 3 days before orthotopic liver transplantation. The results indicated that cholangiocytes responded to extended cold preservation (12 hours) with severe bile duct injures, marked activation of the interleukin-6 (IL-6)/STAT3 signal pathway, and increased expression of cyclin D1 until 7 days after transplantation, and this was followed by compensatory cholangiocyte regeneration. However, rapamycin treatment inhibited STAT3 activation and resulted in decreased cholangiocyte proliferation and delayed biliary recovery after liver transplantation. On the other hand, rapamycin showed no effect on the expression of IL-6. We conclude that the IL-6/STAT3 signal pathway is involved in initiating cholangiocytes to regenerate and repair CIRI. Rapamycin represses cholangiocyte regeneration by inhibiting STAT3 activation, which might have a negative effect on the healing and recovery of bile ducts in grafts with extended cold preservation. Insights gained from this study will be helpful in designing therapy using rapamycin in clinical patients after liver transplantation. Liver Transpl, 2010. © 2010 AASLD. [source]


Interleukin-1, and tumor necrosis factor , inhibit chondrogenesis by human mesenchymal stem cells through NF-,B,dependent pathways,

ARTHRITIS & RHEUMATISM, Issue 3 2009
N. Wehling
Objective The differentiation of mesenchymal stem cells (MSCs) into chondrocytes provides an attractive basis for the repair and regeneration of articular cartilage. Under clinical conditions, chondrogenesis will often need to occur in the presence of mediators of inflammation produced in response to injury or disease. The purpose of this study was to examine the effects of 2 important inflammatory cytokines, interleukin-1, (IL-1,) and tumor necrosis factor , (TNF,), on the chondrogenic behavior of human MSCs. Methods Aggregate cultures of MSCs recovered from the femoral intermedullary canal were used. Chondrogenesis was assessed by the expression of relevant transcripts by quantitative reverse transcription,polymerase chain reaction analysis and examination of aggregates by histologic and immunohistochemical analyses. The possible involvement of NF-,B in mediating the effects of IL-1, was examined by delivering a luciferase reporter construct and a dominant-negative inhibitor of NF-,B (suppressor-repressor form of I,B [srI,B]) with adenovirus vectors. Results Both IL-1, and TNF, inhibited chondrogenesis in a dose-dependent manner. This was associated with a marked activation of NF-,B. Delivery of srI,B abrogated the activation of NF-,B and rescued the chondrogenic response. Although expression of type X collagen followed this pattern, other markers of hypertrophic differentiation responded differently. Matrix metalloproteinase 13 was induced by IL-1, in a NF-,B,dependent manner. Alkaline phosphatase activity, in contrast, was inhibited by IL-1, regardless of srI,B delivery. Conclusion Cell-based repair of lesions in articular cartilage will be compromised in inflamed joints. Strategies for enabling repair under these conditions include the use of specific antagonists of individual pyrogens, such as IL-1, and TNF,, or the targeting of important intracellular mediators, such as NF-,B. [source]