RESUMEN
Polymorphonuclear (PMN) leucocytes participate in acute inflammatory pathologies such as acute respiratory distress syndrome (ARDS) following traumatic injury and shock, which also activates the coagulation system systemically. Trauma can prime the PMN nicotinamide adenine dinucleotide phosphate (NADPH) oxidase complex for an enhanced respiratory burst, but the relative role of various priming agents in this process remains incompletely understood. We therefore set out to identify mediators of PMN priming during coagulation and trauma-shock and determine whether PMN reactive oxygen species (ROS) generated in this manner could influence organ injury and coagulation. Initial experiments demonstrated that PMN are primed for predominantly extracellular ROS production by products of coagulation, which was abrogated by CD88/C5a receptor(C5aR) inhibition. The importance of this was highlighted further by demonstrating that known PMN priming agents result in fractionally different amounts of extracellular versus intracellular ROS release depending on the agent used. Plasma from trauma patients in haemodynamic shock (n = 10) also primed PMN for extracellular ROS in a C5a-dependent manner, which correlated with both complement alternative pathway activation and thrombin generation. Furthermore, PMN primed by preincubation with products of blood coagulation directly caused loss of endothelial barrier function in vitro that was abrogated by C5aR blockade or NADPH oxidase inhibition. Finally, we show in a murine model of trauma-shock that p47phox knock-out (KO) mice with PMN incapable of generating ROS were protected from inflammatory end-organ injury and activated protein C-mediated coagulopathy. In summary, we demonstrate that trauma-shock and coagulation primes PMN for predominantly extracellular ROS production in a C5a-dependent manner that contributes to endothelial barrier loss and organ injury, and potentially enhances traumatic coagulopathy.
Asunto(s)
Coagulación Sanguínea/fisiología , Neutrófilos/inmunología , Especies Reactivas de Oxígeno/metabolismo , Receptor de Anafilatoxina C5a/antagonistas & inhibidores , Choque/patología , Heridas y Lesiones/patología , Adulto , Anciano , Animales , Femenino , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Persona de Mediana Edad , NADPH Oxidasas/antagonistas & inhibidores , NADPH Oxidasas/genética , NADPH Oxidasas/metabolismo , Activación Neutrófila/inmunología , Estallido Respiratorio , Síndrome de Dificultad Respiratoria/inmunología , Síndrome de Dificultad Respiratoria/patología , Choque/inmunología , Trombina/biosíntesis , Heridas y Lesiones/inmunologíaRESUMEN
Critical functions of the immune system are maintained by the ability of myeloid progenitors to differentiate and mature into macrophages. We hypothesized that the cytoprotective gas molecule carbon monoxide (CO), generated endogenously by heme oxygenases (HO), promotes differentiation of progenitors into functional macrophages. Deletion of HO-1, specifically in the myeloid lineage (Lyz-Cre:Hmox1(flfl)), attenuated the ability of myeloid progenitors to differentiate toward macrophages and decreased the expression of macrophage markers, CD14 and macrophage colony-stimulating factor receptor (MCSFR). We showed that HO-1 and CO induced CD14 expression and efficiently increased expansion and differentiation of myeloid cells into macrophages. Further, CO sensitized myeloid cells to treatment with MCSF at low doses by increasing MCSFR expression, mediated partially through a PI3K-Akt-dependent mechanism. Exposure of mice to CO in a model of marginal bone marrow transplantation significantly improved donor myeloid cell engraftment efficiency, expansion and differentiation, which corresponded to increased serum levels of GM-CSF, IL-1α and MCP-1. Collectively, we conclude that HO-1 and CO in part are critical for myeloid cell differentiation. CO may prove to be a novel therapeutic agent to improve functional recovery of bone marrow cells in patients undergoing irradiation, chemotherapy and/or bone marrow transplantation.
Asunto(s)
Monóxido de Carbono/farmacología , Diferenciación Celular/efectos de los fármacos , Hemo-Oxigenasa 1/metabolismo , Macrófagos/efectos de los fármacos , Proteínas de la Membrana/metabolismo , Células Progenitoras Mieloides/efectos de los fármacos , Animales , Trasplante de Médula Ósea , Monóxido de Carbono/metabolismo , Linaje de la Célula , Proliferación Celular , Quimiocina CCL2/sangre , Gases , Factor Estimulante de Colonias de Granulocitos y Macrófagos/sangre , Hemo-Oxigenasa 1/genética , Humanos , Interleucina-1alfa/sangre , Receptores de Lipopolisacáridos/metabolismo , Factor Estimulante de Colonias de Macrófagos/farmacología , Macrófagos/enzimología , Macrófagos/inmunología , Macrófagos/trasplante , Proteínas de la Membrana/genética , Ratones , Ratones Noqueados , Células Progenitoras Mieloides/enzimología , Células Progenitoras Mieloides/inmunología , Células Progenitoras Mieloides/trasplante , Fosfatidilinositol 3-Quinasa/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptor de Factor Estimulante de Colonias de Macrófagos/metabolismo , Transducción de Señal , Factores de Tiempo , Células U937RESUMEN
Under normoxic conditions, nitric oxide (NO) suppresses hepatocyte apoptosis. In contrast, NO contributes to hepatocellular injury in conditions associated with ischemia and reperfusion. To understand this paradoxical effect further, we compared the effects of various doses of NO, delivered from the chemical NO donor S-nitroso-N-acetylpenicillamine (SNAP), under both normoxic and hypoxic tissue culture conditions. We found that the cell death induced by NO under hypoxic conditions, which increased the production of reactive oxygen species, was accompanied by a necrotic morphology with a concomitant early decrease in ATP levels. The NO-induced death of hypoxic hepatocytes was reversed by co-incubation with the anti-oxidant N-acetylcysteine. We conclude that hypoxia-induced oxidative stress subsequent to ATP depletion can switch NO from an anti-apoptotic to a hepatotoxic agent. These findings may have implications for NO-induced liver damage in settings of tissue hypoxia.
Asunto(s)
Apoptosis , Hipoxia de la Célula , Hepatocitos/fisiología , Óxido Nítrico/fisiología , Acetilcisteína/farmacología , Adenosina Trifosfato/metabolismo , Animales , Apoptosis/efectos de los fármacos , Células Cultivadas , Hepatocitos/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Donantes de Óxido Nítrico/farmacología , Oxidación-Reducción , Estrés Oxidativo/fisiología , Penicilamina/análogos & derivados , Penicilamina/farmacología , Ratas , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno/metabolismo , Daño por Reperfusión/fisiopatologíaRESUMEN
BACKGROUND: Intestinal transplantation provokes an intense inflammatory response within the graft muscularis that causes intestinal ileus. We hypothesised that endogenously produced anti-inflammatory substances could be utilised as novel therapeutics. Therefore, we tested the protective effects of inhaled carbon monoxide (CO) and an endogenous haeme oxygenase 1 (HO-1) anti-inflammatory mediator on transplant induced inflammatory responses and intestinal ileus in the rat. METHODS: Gastrointestinal transit of non-absorbable FITC labelled dextran and in vitro jejunal circular muscle contractions were measured in controls and syngeneic orthotopic transplanted animals with and without CO inhalation (250 ppm for 25 hours). Inflammatory mRNAs for interleukin (IL)-6, IL-1beta, tumour necrosis factor alpha (TNF-alpha), intercellular adhesion molecule 1 (ICAM-1), inducible nitric oxide (iNOS), cyclooxygenase 2 (COX-2), and IL-10 were quantified by real time reverse transcriptase-polymerase chain reaction and HO-1 by northern blot. Histochemical stains characterised neutrophil infiltration and enterocyte apoptosis. RESULTS: Transplantation delayed transit and suppressed jejunal circular muscle contractility. Transplantation induced dysmotility was significantly improved by CO inhalation. Transplantation initiated a significant upregulation in IL-6, IL-1beta, TNF-alpha, ICAM-1, iNOS, COX-2, and HO-1 mRNAs with the graft muscularis. CO inhalation significantly decreased expression of IL-6, IL-1beta, iNOS, and COX-2 mRNAs. CO also significantly decreased serum nitrite levels (iNOS activity). CONCLUSIONS: CO inhalation significantly improved post-transplant motility and attenuated the inflammatory cytokine milieu in the syngeneic rat transplant model. Thus clinically providing CO, the end product of the anti-inflammatory HO-1 pathway, may prove to be an effective therapeutic adjunct for clinical small bowel transplantation.
Asunto(s)
Monóxido de Carbono/administración & dosificación , Motilidad Gastrointestinal/inmunología , Intestino Delgado/trasplante , Animales , Betanecol/farmacología , Northern Blotting , Ciclooxigenasa 2 , Citocinas/metabolismo , Motilidad Gastrointestinal/efectos de los fármacos , Motilidad Gastrointestinal/fisiología , Tránsito Gastrointestinal/inmunología , Hemo Oxigenasa (Desciclizante)/metabolismo , Hemo-Oxigenasa 1 , Inflamación/etiología , Inflamación/fisiopatología , Molécula 1 de Adhesión Intercelular/metabolismo , Interleucina-1/metabolismo , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Intestino Delgado/inmunología , Intestino Delgado/fisiología , Isoenzimas/metabolismo , Masculino , Contracción Muscular/efectos de los fármacos , Óxido Nítrico Sintasa/metabolismo , Prostaglandina-Endoperóxido Sintasas/metabolismo , Ratas , Ratas Sprague-Dawley , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
Nitric oxide has recently been shown to inhibit the proliferation of several types of cells, including osteoclasts. Both osteoclasts and osteoblasts have inducible nitric oxide synthase and produce nitric oxide. Although the direct effect of nitric oxide on osteoblasts in general and osteoblast proliferation in particular has not been delineated, the authors performed studies to clarify the role of nitric oxide on osteoblast proliferation and metabolism. Cultures of human osteoblasts were exposed to 0.1, 1.0, and 10 microM of the nitric oxide releasing agent 3-morpholino sydnonimine (SIN-1) for 7 days. Cells were evaluated for proliferation and production of alkaline phosphatase and osteocalcin. Osteoblasts exhibited decreased proliferation relative to control cultures at 1.0 and 10 microM concentrations of SIN-1 (p < 0.05). Concentrations of 1.0 and 10 microM of SIN-1 effected a decreased production of osteocalcin and alkaline phosphatase (p < 0.05). The results of these studies indicate that nitric oxide may play a critical role by which osteoblasts exhibit self-regulation of mineral metabolism.
Asunto(s)
Óxido Nítrico/fisiología , Osteoblastos/metabolismo , Fosfatasa Alcalina/biosíntesis , División Celular , Células Cultivadas , Preescolar , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/farmacología , Humanos , Molsidomina/análogos & derivados , Molsidomina/farmacología , Óxido Nítrico/antagonistas & inhibidores , Nitroarginina/farmacología , Osteoblastos/citología , Osteocalcina/biosíntesisRESUMEN
Six patients with parotid pseudocysts following face lifts are reported. Insertion of a suction drain in three patients provided earlier resolution than repeated aspiration in the other three.
Asunto(s)
Quistes/cirugía , Enfermedades de las Parótidas/cirugía , Ritidoplastia/efectos adversos , Anciano , Quistes/etiología , Femenino , Humanos , Enfermedades de las Parótidas/etiología , SucciónRESUMEN
In spite of adequate preoperative evaluation, lagophthalmos may appear during a brow lift procedure if the patient has had a prior upper lid blepharoplasty. Relief of this condition may be obtained by incising the upper lid scar and spreading the wound. Subsequent granulation results in an acceptable scar.