RESUMEN
BACKGROUND: Angiotensin-converting enzyme inhibitor (ACEI)-induced angioedema can occur at any point during therapy and, when severe, can require mechanical ventilation. Standard agents for anaphylactic reactions have limited efficacy for bradykinin-mediated angioedema and, therefore, agents approved for hereditary angioedema are increasingly prescribed for these patients. OBJECTIVE OF THE REVIEW: This systematic review critically evaluates evidence describing the off-label use of fresh frozen plasma (FFP), prothrombin complex concentrate (PCC), complement 1 esterase inhibitor (C1-INH), icatibant, and ecallantide for treatment of ACEI-induced angioedema. DISCUSSION: A PubMed search was conducted and articles were cross-referenced for additional citations. All full-text clinical trials, case series, and case reports published in the English language describing pharmacologic treatment of ACEI-induced angioedema were included. Thirty-seven publications detailing FFP, PCC, and regimens approved for hereditary angioedema, including icatibant, ecallantide, and C1-INH, are reviewed extensively. CONCLUSIONS: While findings of decreased time to symptom resolution or a cessation in symptom progression have been reported with each of these therapies, additional data showing clinically relevant implications, such as reduced intensive care unit length of stay or avoidance of mechanical ventilation, are warranted, especially when taking cost into consideration. FFP has limited evidence demonstrating a benefit for treatment of ACEI-induced angioedema without consistent dosing strategies. However, given its wide availability and low potential for adverse reactions, FFP therapy may be reasonable. Of the novel agents traditionally used for hereditary angioedema, icatibant has the highest level of evidence and has been reported to be successful in limiting the progression of angioedema.
Asunto(s)
Angioedema/tratamiento farmacológico , Angioedema/etiología , Inhibidores de la Enzima Convertidora de Angiotensina/efectos adversos , Uso Fuera de lo Indicado , Angioedema/inducido químicamente , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Factores de Coagulación Sanguínea/farmacología , Factores de Coagulación Sanguínea/uso terapéutico , Bradiquinina/análogos & derivados , Bradiquinina/farmacología , Bradiquinina/uso terapéutico , Proteínas Inactivadoras del Complemento 1/farmacología , Proteínas Inactivadoras del Complemento 1/uso terapéutico , Humanos , Péptidos/farmacología , Péptidos/uso terapéutico , Plasma/metabolismoRESUMEN
BACKGROUND: Ethanol feeding in mice activates complement via C1q binding to apoptotic cells in the liver; complement contributes to ethanol-induced inflammation and injury. Despite the critical role of C1q in ethanol-induced injury, the mechanism by which ethanol activates C1q remains poorly understood. Secretory IgM (sIgM), traditionally considered to act as an anti-microbial, also has critical housekeeping functions, facilitating clearance of apoptotic cells, at least in part through activation of C1q. Therefore, we hypothesized that (1) ethanol-induced apoptosis in the liver recruits sIgM, facilitating the activation of C1q and complement and (2) C1INH (C1 esterase inhibitor), which inhibits C1 functional activity, prevents complement activation and decreases ethanol-induced liver injury. METHODS: Female C57BL/6 wild-type, C1qa(-/-), BID(-/-) and sIgM(-/-) mice were fed ethanol containing liquid diets or pair-fed control diets. C1INH or vehicle was given via tail vein injection to ethanol- or pair-fed wild-type mice at 24 and 48h prior to euthanasia. RESULTS: Ethanol exposure increased apoptosis in the liver, as well as the accumulation of IgM in the liver. In the early stages of ethanol feeding, C1q co-localized with IgM in the peri-sinusoidal space of the liver and accumulation of IgM and C3b was dependent on ethanol-induced BID-dependent apoptosis. sIgM(-/-) mice were protected from both ethanol-induced activation of complement and early ethanol-induced liver injury when compared to wild-type mice. Treatment with C1INH also decreased hepatic C3b deposition and ethanol-induced injury. CONCLUSION: These data indicate that sIgM contributes to activation of complement and ethanol-induced increases in inflammatory cytokine expression and hepatocyte injury in the early stages of ethanol-induced liver injury.
Asunto(s)
Apoptosis , Activación de Complemento , Complemento C1q/inmunología , Inmunoglobulina M/inmunología , Hepatopatías Alcohólicas/inmunología , Animales , Proteínas Inactivadoras del Complemento 1/farmacología , Proteína Inhibidora del Complemento C1 , Complemento C1q/antagonistas & inhibidores , Citocinas/biosíntesis , Femenino , Hepatocitos/inmunología , Hepatopatías Alcohólicas/patología , Ratones , Ratones Endogámicos C57BL , SolubilidadRESUMEN
Plasmodium falciparum-induced severe malaria remains a continuing problem in areas of endemicity, with elevated morbidity and mortality. Drugs targeting mechanisms involved in severe malaria pathology, including cytoadhesion of infected red blood cells (RBCs) to host receptors and production of proinflammatory cytokines, are still necessary. Human C1-inhibitor (C1INH) is a multifunctional protease inhibitor that regulates coagulation, vascular permeability, and inflammation, with beneficial effects in inflammatory disease models, including septic shock. We found that human C1INH, at therapeutically relevant doses, blocks severe malaria pathogenic processes by 2 distinct mechanisms. First, C1INH bound to glycan moieties within P. falciparum glycosylphosphatidylinositol (PfGPI) molecules on the parasite surface, inhibiting parasite RBC invasion and proinflammatory cytokine production by parasite-stimulated monocytes in vitro and reducing parasitemia in a rodent model of experimental cerebral malaria (ECM) in vivo. Second, C1INH bound to host CD36 and chondroitin sulfate A molecules, interfering with cytoadhesion of infected RBCs by competitive binding to these receptors in vitro and reducing sequestration in specific tissues and protecting against ECM in vivo. This study reveals that C1INH is a potential therapeutic antimalarial molecule able to interfere with severe-disease etiology at multiple levels through specific interactions with both parasite PfGPIs and host cell receptors.
Asunto(s)
Adhesión Celular/efectos de los fármacos , Proteínas Inactivadoras del Complemento 1/metabolismo , Proteínas Inactivadoras del Complemento 1/farmacología , Glicosilfosfatidilinositoles/metabolismo , Interacciones Huésped-Parásitos/efectos de los fármacos , Malaria Cerebral/metabolismo , Malaria Cerebral/parasitología , Proteínas Protozoarias/metabolismo , Animales , Línea Celular Tumoral , Proteína Inhibidora del Complemento C1 , Modelos Animales de Enfermedad , Eritrocitos/parasitología , Femenino , Humanos , Malaria Cerebral/sangre , Ratones , Ratones Endogámicos C57BL , Plasmodium berghei/metabolismo , Plasmodium berghei/patogenicidad , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacologíaRESUMEN
Coagulation factor XII (fXII) is important for arterial thrombosis, but its physiological activation mechanisms are unclear. In this study, we elucidated the role of platelets and platelet-derived material in fXII activation. FXII activation was only observed upon potent platelet stimulation (with thrombin, collagen-related peptide, or calcium ionophore, but not ADP) accompanied by phosphatidylserine exposure and was localised to the platelet surface. Platelets from three patients with grey platelet syndrome did not activate fXII, which suggests that platelet-associated fXII-activating material might be released from α-granules. FXII was preferentially bound by phosphotidylserine-positive platelets and annexin V abrogated platelet-dependent fXII activation; however, artificial phosphotidylserine/phosphatidylcholine microvesicles did not support fXII activation under the conditions herein. Confocal microscopy using DAPI as a poly-phosphate marker did not reveal poly-phosphates associated with an activated platelet surface. Experimental data for fXII activation indicates an auto-inhibition mechanism (ki/ka = 180 molecules/platelet). Unlike surface-associated fXII activation, platelet secretion inhibited activated fXII (fXIIa), particularly due to a released C1-inhibitor. Platelet surface-associated fXIIa formation triggered contact pathway-dependent clotting in recalcified plasma. Computer modelling suggests that fXIIa inactivation was greatly decreased in thrombi under high blood flow due to inhibitor washout. Combined, the surface-associated fXII activation and its inhibition in solution herein may be regarded as a flow-sensitive regulator that can shift the balance between surface-associated clotting and plasma-dependent inhibition, which may explain the role of fXII at high shear and why fXII is important for thrombosis but negligible in haemostasis.
Asunto(s)
Inhibidores de Factor de Coagulación Sanguínea/metabolismo , Plaquetas/metabolismo , Membrana Celular/metabolismo , Factor XII/agonistas , Factor XII/antagonistas & inhibidores , Adulto , Anciano , Anciano de 80 o más Años , Coagulación Sanguínea/efectos de los fármacos , Inhibidores de Factor de Coagulación Sanguínea/farmacología , Micropartículas Derivadas de Células/metabolismo , Proteínas Inactivadoras del Complemento 1/metabolismo , Proteínas Inactivadoras del Complemento 1/farmacología , Activación Enzimática/efectos de los fármacos , Factor XII/química , Factor XII/metabolismo , Familia , Femenino , Síndrome de Plaquetas Grises/sangre , Síndrome de Plaquetas Grises/metabolismo , Humanos , Masculino , Modelos Biológicos , Unión Proteica , Vesículas Secretoras/metabolismoRESUMEN
Human C1 inhibitor (C1INH) prevents endotoxin shock via a direct interaction with Gram-negative bacterial lipopolysaccharide (LPS) and improves survival in animal models of sepsis. In this report, we further characterize the interaction of C1INH with LPS and whole live bacteria. We investigate C1INH interactions with LPS from five different strains of Gram-negative enteric bacteria known to participate in the pathogenesis of human sepsis. Treatment with C1INH improved survival in mice with endotoxin shock induced by LPS from Salmonella enterica serovar typhimurium as previously shown, as well as LPS from Escherichia coli O55:B5 and Pseudomonas aeruginosa, and a trend to improved survival was observed when Klebsiella pneumoniae and Serratia marcescens LPS were used. Enzyme-linked immunosorbent assay and native polyacrylamide gel electrophoresis shift experiments demonstrated a direct interaction of C1INH with LPS from all the strains studied. The binding of both native and reactive center-cleaved, inactive C1INH results in inhibition of LPS-induced proinflammatory cytokine production. Furthermore, we demonstrate the ability of C1INH to bind at the surface of only a restricted number of whole live Gram-negative bacteria as well as mutant bacteria expressing a truncated LPS lacking the O-antigen. These data reveal the interaction of C1INH with a wide range of enteric bacterial LPS and strongly suggest that the interaction between C1INH and the surface of Gram-negative microorganisms is determined by the length of the polysaccharide chain of the endotoxin molecule.
Asunto(s)
Proteínas Inactivadoras del Complemento 1/farmacología , Bacterias Gramnegativas/efectos de los fármacos , Infecciones por Bacterias Gramnegativas/prevención & control , Lipopolisacáridos/antagonistas & inhibidores , Choque Séptico/prevención & control , Animales , Proteína Inhibidora del Complemento C1 , Modelos Animales de Enfermedad , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Factor de Necrosis Tumoral alfa/efectos de los fármacos , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
OBJECTIVES: Arterial pressure induced vein graft injury can result in endothelial loss, accelerated atherosclerosis and vein graft failure. Inflammation, including complement activation, is assumed to play a pivotal role herein. Here, we analyzed the effects of C1-esterase inhibitor (C1inh) on early vein graft remodeling. METHODS: Human saphenous vein graft segments (n=8) were perfused in vitro with autologous blood either supplemented or not with purified human C1inh at arterial pressure for 6h. The vein segments and perfusion blood were analyzed for cell damage and complement activation. In addition, the effect of purified C1inh on vein graft remodeling was analyzed in vivo in atherosclerotic C57Bl6/ApoE3 Leiden mice, wherein donor caval veins were interpositioned in the common carotid artery. RESULTS: Application of C1inh in the in vitro perfusion model resulted in significantly higher blood levels and significantly more depositions of C1inh in the vein wall. This coincided with a significant reduction in endothelial loss and deposition of C3d and C4d in the vein wall, especially in the circular layer, compared to vein segments perfused without supplemented C1inh. Administration of purified C1inh significantly inhibited vein graft intimal thickening in vivo in atherosclerotic C57Bl6/ApoE3 Leiden mice, wherein donor caval veins were interpositioned in the common carotid artery. CONCLUSION: C1inh significantly protects against early vein graft remodeling, including loss of endothelium and intimal thickening. These data suggest that it may be worth considering its use in patients undergoing coronary artery bypass grafting.
Asunto(s)
Aterosclerosis/complicaciones , Presión Sanguínea , Proteínas Inactivadoras del Complemento 1/farmacología , Puente de Arteria Coronaria/efectos adversos , Vena Safena/efectos de los fármacos , Injerto Vascular/efectos adversos , Venas Cavas/efectos de los fármacos , Animales , Apolipoproteína E3 , Aterosclerosis/genética , Aterosclerosis/inmunología , Aterosclerosis/patología , Aterosclerosis/fisiopatología , Proteína Inhibidora del Complemento C1 , Complemento C3d/metabolismo , Complemento C4b/metabolismo , Modelos Animales de Enfermedad , Células Endoteliales/efectos de los fármacos , Células Endoteliales/patología , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Infiltración Neutrófila , Fragmentos de Péptidos/metabolismo , Perfusión , Vena Safena/inmunología , Vena Safena/patología , Vena Safena/trasplante , Factores de Tiempo , Venas Cavas/inmunología , Venas Cavas/patología , Venas Cavas/trasplanteAsunto(s)
Angioedemas Hereditarios/tratamiento farmacológico , Proteínas Inactivadoras del Complemento 1/uso terapéutico , Proteína Inhibidora del Complemento C1/uso terapéutico , Péptidos/uso terapéutico , Angioedemas Hereditarios/fisiopatología , Ensayos Clínicos como Asunto , Proteínas Inactivadoras del Complemento 1/efectos adversos , Proteínas Inactivadoras del Complemento 1/farmacología , Proteína Inhibidora del Complemento C1/efectos adversos , Proteína Inhibidora del Complemento C1/farmacología , Aprobación de Drogas , Humanos , Péptidos/efectos adversos , Péptidos/farmacologíaRESUMEN
C1-Inhibitor (C1-INH) is an important biological inhibitor, regulating several protein cascade systems. Recent research has shown that the molecule exhibits properties not dependent on its protease inhibition activity. Serum and whole blood from pigs and humans were pre-incubated with C1-INH, iC1-INH or the complement inhibitors SPICE or compstatin. Whole, live Escherichia coli were then added for further incubation. Complement activation, a range of cytokines, chemokines and growth factors, as well as the leukocyte activation markers wCD11R3 (pig) and CD11b (human) were measured. Both C1-INH and iC1-INH dose-dependently and significantly (P<0.05) reduced a range of E. coli-induced pro-inflammatory cytokines and chemokines in porcine and human whole blood, as well as growth factors in human whole blood. Differences between the two forms of C1-INH and between the two species were modest. Most of these anti-inflammatory effects could not be explained by complement inhibition, as specific complement inhibitors had minor effect on several of the mediators. C1-Inhibitor had no inhibitory effect on E. coli-induced complement activation, while iC1-INH enhanced complement activation. The presented data indicate that C1-INH has broad anti-inflammatory effects in E. coli-induced inflammation in pig and human whole blood. These effects are largely independent of the protease inhibition activity.
Asunto(s)
Antiinflamatorios , Proteínas Inactivadoras del Complemento 1/farmacología , Inhibidores de Proteasas/farmacología , Animales , Anticoagulantes/farmacología , Antígenos CD11/biosíntesis , Quimiocinas/biosíntesis , Activación de Complemento/efectos de los fármacos , Citocinas/biosíntesis , Citometría de Flujo , Infecciones por Bacterias Gramnegativas/patología , Hirudinas/farmacología , Humanos , Técnicas para Inmunoenzimas , Técnicas In Vitro , Indicadores y Reactivos , Inflamación/patología , Péptidos y Proteínas de Señalización Intercelular/biosíntesis , Activación de Macrófagos/efectos de los fármacos , Proteínas Recombinantes/farmacología , PorcinosRESUMEN
A single-site mutant of prouPA (M5) spared haemostatic fibrin during thrombolysis in dogs. Zymograms of plasma from these dogs showed an unusual inhibitor complex with C1-inhibitor (C1I). Purified C1I added to human plasma enhanced the fibrin-specificity of M5. In the present study, the effect of recombinant human C1I (recC1I) on high-dose M5 and tPA were compared using fluorescein-labeled standardised clots in a plasma milieu. The shortest time to complete clot lysis (maximum rate) was first determined. This was approximately 65% per hour for both activators. By contrast, their top fibrin-specific lysis rate (<20% fibrinogen depletion) was less than half maximum (25-30% per hour). Adding recC1I (250-750 microg/ml) did not affect fibrinolysis, but prevented fibrinogenolysis and plasminogen depletion by M5, raising its fibrin-specific lysis rate to the maximum. With tPA, the recC1I modestly attenuated fibrinogenolysis, raising its fibrin-specific rate to about half the maximum. Consistent with this, the t(1/2) inhibition by C1I was approximately 90 min for tPA compared with ~10 min for tcM5. The t(1/2) of C1I for plasmin was ~2 min. Zymograms of plasma after clot lysis indicated that recC1I prevented non-specific tcM5 generation from M5, as evidenced by suppression of tcM5:C1I complexes. In conclusion, recC1I raised the fibrin-specificity of M5 in plasma so that a maximum lysis rate could be achieved without fibrinogenolysis. The inhibition by C1I of non-specific but not fibrin-dependent plasminogen activation could not be duplicated by other serpins. The findings provide a potential means to optimize both the efficacy and safety of thrombolysis.
Asunto(s)
Proteínas Inactivadoras del Complemento 1/farmacología , Fibrinólisis/efectos de los fármacos , Activador de Plasminógeno de Tipo Uroquinasa/administración & dosificación , Activador de Plasminógeno de Tipo Uroquinasa/genética , Animales , Perros , Fibrinógeno/metabolismo , Fibrinolisina/antagonistas & inhibidores , Fibrinólisis/fisiología , Fibrinolíticos/administración & dosificación , Fibrinolíticos/efectos adversos , Humanos , Técnicas In Vitro , Cinética , Mutagénesis Sitio-Dirigida , Plasminógeno/metabolismo , Inhibidor 1 de Activador Plasminogénico/farmacología , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/efectos adversos , Proteínas Recombinantes/antagonistas & inhibidores , Proteínas Recombinantes/genética , Proteínas Recombinantes/farmacología , Terapia Trombolítica/efectos adversos , Terapia Trombolítica/métodos , Activador de Tejido Plasminógeno/administración & dosificación , Activador de Tejido Plasminógeno/efectos adversos , Activador de Tejido Plasminógeno/antagonistas & inhibidores , Activador de Plasminógeno de Tipo Uroquinasa/efectos adversos , Activador de Plasminógeno de Tipo Uroquinasa/antagonistas & inhibidores , alfa 2-Antiplasmina/farmacologíaRESUMEN
Hereditary angioedema (HAE) is a rare disorder characterized by recurrent attacks of swelling that may involve multiple anatomical locations. In the majority of patients, it is caused by a functional or quantitative defect in the C1 inhibitor (C1-INH), which is an important regulator of the complement, fibrinolytic, kallikrein-kinin and coagulation systems. Standard treatments used for other types of angioedema are ineffective for HAE. Traditional therapies for HAE, including fresh frozen plasma, epsilon-aminocaproic acid and danazol, may be well tolerated and effective in some patients; however, there are limitations both in their safety and efficacy. Several novel therapies have completed phase III trials in the US, including: (i) plasma-derived C1-INH replacement therapies (Berinert P and Cinryze); (ii) a recombinant C1-INH replacement therapy (conestat alfa; Rhucin); (iii) a kallikrein inhibitor (ecallantide [DX-88]); and (iv) a bradykinin-2-receptor antagonist (icatibant). Both Berinert P and Cinryze are reported to have excellent efficacy and safety data from phase III trials. Currently, only Cinryze has been approved for prophylactic use in the US. US FDA approval for other novel agents to treat HAE and for the use of Cinryze in the treatment of acute attacks is pending.
Asunto(s)
Angioedemas Hereditarios/tratamiento farmacológico , Angioedemas Hereditarios/prevención & control , Angioedemas Hereditarios/etiología , Angioedemas Hereditarios/fisiopatología , Ensayos Clínicos Fase III como Asunto , Proteínas Inactivadoras del Complemento 1/farmacología , Proteínas Inactivadoras del Complemento 1/uso terapéutico , Proteína Inhibidora del Complemento C1/efectos de los fármacos , Proteína Inhibidora del Complemento C1/farmacología , Humanos , Modelos Teóricos , Estudios Multicéntricos como Asunto , Estados UnidosRESUMEN
C1 inhibitor is a potent anti-inflammatory protein as it is the major inhibitor of proteases of the contact and the complement systems. C1-inhibitor administration is an effective therapy in the treatment of patients with hereditary angioedema (HAE) who are genetically deficient in C1 inhibitor. Owing to its ability to modulate the contact and complement systems and the convincing safety profile, plasma-derived C1 inhibitor is an attractive therapeutic protein to treat inflammatory diseases other than HAE. In the present review we give an overview of the biology of C1 inhibitor and its use in HAE. Furthermore, we discuss C1 inhibitor as an experimental therapy in diseases such as sepsis and myocardial infarction.
Asunto(s)
Proteínas Inactivadoras del Complemento 1/farmacología , Inhibidores de Serina Proteinasa/farmacología , Angioedemas Hereditarios/tratamiento farmacológico , Animales , Activación de Complemento , Proteínas Inactivadoras del Complemento 1/uso terapéutico , Proteína Inhibidora del Complemento C1 , Puente de Arteria Coronaria , Humanos , Infarto del Miocardio/tratamiento farmacológico , Infarto del Miocardio/cirugía , Inhibidores de Serina Proteinasa/uso terapéuticoRESUMEN
Antibody-mediated rejection (AMR) is usually poorly controlled, especially in the context of pretransplant immunization, and remains an unsolved issue in xenotransplantation. In order to study prevention and/or treatment of AMR through an early blockade of the complement classical pathway, we designed two strategies to test the effect of a new recombinant human C1-inhibitor that inhibits C1 esterase (rhC1-INH; Pharming, The Netherlands), in a complement-dependent cytotoxicity assay, in the contexts of pretransplant anti-donor alloimmunization and pig-to-primate combinations in order to compare the situations. RhC1-INH appeared to be efficient, in allo- and xenotransplantation settings to block cytotoxicity when given at the initiation of (preventive strategy) or during (curative strategy) the cytotoxicity assay. Importantly, we showed that a small amount of exogenous rhC1-INH was sufficient to prevent cytotoxicity induced by anti-donor alloantibody, thus possibly helping to prevent or treat AMR in preimmunized patients. These in vitro data lead to future in vivo studies in models of AMR in pigs and baboons in allotransplantation and xenotransplantation, in which cytotoxicity due to Gal and non-Gal antibodies is so detrimental.
Asunto(s)
Anticuerpos Heterófilos/inmunología , Supervivencia Celular/efectos de los fármacos , Proteínas Inactivadoras del Complemento 1/inmunología , Rechazo de Injerto/inmunología , Isoanticuerpos/inmunología , Trasplante Heterólogo/inmunología , Animales , Anticuerpos Heterófilos/farmacología , Supervivencia Celular/inmunología , Proteínas Inactivadoras del Complemento 1/farmacología , Rechazo de Injerto/prevención & control , Humanos , Isoanticuerpos/farmacología , PorcinosRESUMEN
BACKGROUND: Prourokinase (prouPA) is unstable in plasma at therapeutic concentrations. A mutant form, M5, made more stable by reducing its intrinsic activity was therefore developed. Activation to two-chain M5 (tcM5) induced a higher catalytic activity than two-chain urokinase plasminogen activator (tcuPA), implicating an active site functional difference. Consistent with this, an unusual tcM5 complex with plasma C1-inhibitor was recently described in dog and human plasma. The effect of C1-inhibitor on fibrinolysis and fibrinogenolysis by M5 is the subject of this study. METHODS AND RESULTS: Zymograms of tcM5 and tcuPA incubated in plasma revealed prominent tcM5-C1-inhibitor complexes, which formed within 5 min. The inhibition rate by purified human C1-inhibitor (250 microg mL(-1)) was about 7-fold faster for tcM5 than it was for tcuPA (10 microg mL(-1)). The effect of the inhibitor on the stability of M5 and prouPA was determined by incubating them in plasma at high concentrations (10-20 microg mL(-1)) +/- C1-inhibitor supplementation. Above 10 microg mL(-1), depletion of all plasma plasminogen occurred, indicating plasmin generation and tcM5/tcuPA formation. With supplemental C1-inhibitor, M5 stability was restored but not prouPA stability. Clot lysis by M5 +/- supplemental C1-inhibitor showed no attenuation of the rate of fibrinolysis, whereas fibrinogenolysis was prevented by C1-inhibitor. Moreover, because of higher dose-tolerance, the rate of fibrin-specific lysis reached that achievable by non-specific fibrinolysis without inhibitor. CONCLUSIONS: Plasma C1-inhibitor stabilized M5 in its proenzyme configuration in plasma by inhibiting tcM5 and thereby non-specific plasminogen activation. At the same time, fibrin-specific plasminogen activation remained unimpaired. This unusual dissociation of effects has significant implications for improving the safety and efficacy of fibrinolysis.
Asunto(s)
Proteínas Inactivadoras del Complemento 1/farmacología , Fibrina/metabolismo , Plasminógeno/efectos de los fármacos , Serpinas/farmacología , Activador de Plasminógeno de Tipo Uroquinasa/metabolismo , Proteína Inhibidora del Complemento C1 , Electroforesis en Gel de Poliacrilamida , Fibrinólisis , Humanos , Plasminógeno/metabolismo , Activador de Plasminógeno de Tipo Uroquinasa/genéticaRESUMEN
Myocardial ischemia-reperfusion injury can be related to complement activation with generation of chemotactic mediators, release of cytokines, leukocyte accumulation, and subsequent severe tissue injury. In this regard, activation of transcription factors (i.e., NFkappaB) and de novo protein synthesis or inflammatory protein degradation seems to play an important role. In the present study, we analyzed the cardiac protein expression following myocardial ischemia (60 min) and reperfusion (180 min) in a rabbit model utilizing two-dimensional electrophoresis and nanoHPLC/ESI-MS/MS for biochemical protein identification. To achieve cardioprotective effects, we used a novel highly selective small molecule C1s inhibitor administered 5 min prior to reperfusion. The reduction of myocardial injury was observed as diminished plasma creatine kinase activity in C1s-INH-248-treated animals (65.2+/-3 vs. 38.5+/-3 U/g protein after 3 h of reperfusion, P<0.05). With proteome analysis we were able to detect 509+/-21 protein spots on the gels of the 3 groups. A pattern of 480 spots with identical positions was found on every gel of myocardial tissue of sham animals, vehicle and C1s-INH-248-treated animals. We analyzed 11 spots, which were identified by mass spectrometry: Superoxide dismutase, alpha-crystallin-chain-B, mitochondrial stress protein, Mn SOD, ATP synthase A chain heart isoform, creatine kinase, and troponin T. All of these proteins were significantly decreased in the vehicle group when we compared to sham-treated animals. Treatment with C1s-INH-248 preserved levels of these proteins. Thus, blocking the classical complement pathway with a highly specific and potent synthetic inhibitor of the activated C1 complex archives cardio-protection by altering and preserving different anti-inflammatory and cytoprotective cascades.
Asunto(s)
Proteínas del Sistema Complemento/fisiología , Isquemia Miocárdica/metabolismo , Daño por Reperfusión Miocárdica/metabolismo , Miocardio/metabolismo , Proteoma/análisis , Secuencia de Aminoácidos , Animales , Biomarcadores/análisis , Proteínas Inactivadoras del Complemento 1/farmacología , Proteínas del Sistema Complemento/efectos de los fármacos , Creatina Quinasa/análisis , Electrocardiografía , Masculino , Proteínas Asociadas a Microtúbulos/análisis , Datos de Secuencia Molecular , Isquemia Miocárdica/patología , Isquemia Miocárdica/fisiopatología , Daño por Reperfusión Miocárdica/patología , Daño por Reperfusión Miocárdica/fisiopatología , Miocardio/patología , Necrosis/patología , Neutrófilos/fisiología , Conejos , Superóxido Dismutasa/análisis , Superóxido Dismutasa/química , Cadena B de alfa-Cristalina/análisisRESUMEN
C3 is common to all pathways of complement activation augmenting ischemia/reperfusion (I/R)-induced myocardial injury and cardiac dysfunction. Complement inhibition with the complement regulatory protein, C1 inhibitor (C1INH), obviously exerts cardioprotective effects. Here, we examine whether C1INH regulates C3 activity in the ischemic myocardial tissue. C1INH markedly suppressed C3 mRNA expression and protein synthesis in both a model of I/R-induced rat acute myocardial infarction (AMI) and the cultured rat H9c2 heart myocytes. At least, this regulation was at the transcriptional level in response to oxygen tension. In vitro, C3 deposition on, and binding to, the surface of rat myocardial cells were significantly blocked by C1INH treatment. C1INH could inhibit classical complement-mediated cell lysis via suppressing the biological activity of C3. Therefore, C1INH, in addition to inhibition of the systemic complement activation, prevents myocardial cell injury via a direct inhibitory role in the local myocardial C3 activity.
Asunto(s)
Proteínas Inactivadoras del Complemento 1/farmacología , Complemento C3/metabolismo , Daño por Reperfusión Miocárdica/metabolismo , Animales , Hipoxia de la Célula/efectos de los fármacos , Línea Celular , Pollos , Complemento C3/genética , Eritrocitos/efectos de los fármacos , Femenino , Hemólisis/efectos de los fármacos , Masculino , Daño por Reperfusión Miocárdica/genética , Daño por Reperfusión Miocárdica/patología , Oxígeno/metabolismo , Unión Proteica , Ratas , Ratas Sprague-DawleyRESUMEN
The mammalian uterus faces unique immunological challenges. It must nurture and protect the semiallogenic fetus from attack by the maternal immune system while guarding against infection by pathogens that compromise fetal and maternal health. Complement has recently been implicated in the etiology of pregnancy loss, but its regulation by steroid hormones and its role in host defense in the uterus are not clearly defined. Here we use biochemical, functional, and physiological assays to elucidate the regulation of complement proteins in the rat uterus. We demonstrate that estrogens (17 beta-estradiol) and glucocorticoids (dexamethasone) have major, but opposing, effects on the amount and latent activity of complement effectors in the uterus. Treatment with 17 beta-estradiol induced vasodilation and an increase in vascular permeability, which resulted in extravasation of plasma and complement into the uterus, rather than de novo complement biosynthesis. In vitro assays revealed that 17 beta-estradiol induced a potent bactericidal activity in uterine luminal fluid and that the antibacterial component was complement. These proinflammatory and immunomodulatory effects were evident within 4 h of treatment and were blocked by coadministration of dexamethasone. We also found that estrogen effects on the vasculature were mediated in part by activation of the contact system and bradykinin B1 receptors. These results indicate that complement plays a central role in innate immunity in the female reproductive tract and suggest that estrogens or glucocorticoids might be used therapeutically to enhance or inhibit complement-dependent processes in the uterus.
Asunto(s)
Proteínas del Sistema Complemento/metabolismo , Estrógenos/farmacología , Glucocorticoides/farmacología , Útero/efectos de los fármacos , Útero/fisiología , Animales , Líquidos Corporales/microbiología , Bradiquinina/análogos & derivados , Bradiquinina/farmacología , Proteínas Inactivadoras del Complemento 1/farmacología , Proteína Inhibidora del Complemento C1 , Proteínas del Sistema Complemento/efectos de los fármacos , Proteínas del Sistema Complemento/genética , Dexametasona/farmacología , Escherichia coli/patogenicidad , Estradiol/farmacología , Femenino , Reacción en Cadena de la Polimerasa/métodos , Ratas , Ratas Sprague-Dawley , Receptor de Bradiquinina B1/efectos de los fármacos , Receptor de Bradiquinina B1/metabolismo , Serpinas/farmacologíaRESUMEN
Lesions in the CNS of patients with multiple sclerosis (MS) often fail to remyelinate, resulting in neurological dysfunction. A key factor seems to be the inefficiency of oligodendrocyte precursor cells (OPCs). We recently reported antibodies against heat shock protein 90beta (Hsp90beta) in MS patients that recognized the antigen on the OPC surface. This study investigates the mechanism and result of anti-Hsp90beta antibody attack. These antibodies induced OPC death in culture in a complement-dependent fashion. Anti-Hsp90beta antibody-induced, complement-mediated OPC death only operated in these cells and caused a significant reduction in the number of O4-positive pro-oligodendrocytes (pre-oligodendrocytes). Adult cultured OPCs also expressed Hsp90beta on their cell surface and were attacked by anti-Hsp90beta antibodies leading to a significant decrease in the pre-oligodendrocyte population. In the presence of low levels of anti-Hsp90beta antibody--i.e. in the range seen in the CSF of MS patients--the complement concentration was critical to reduce the pre-oligodendrocyte population (via attack to OPCs). Higher concentrations of anti-Hsp90beta antibodies and complement became extinct the pre-oligodendrocytes. Complement 1-esterase inhibitor prevented these effects in the pre-oligodendrocyte population. These findings demonstrate, for the first time in vitro, a feasible mechanism to decrease the production of new oligodendrocytes, thus limiting the possibility of remyelination.
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Anticuerpos Bloqueadores/farmacología , Proteínas HSP90 de Choque Térmico/inmunología , Esclerosis Múltiple/patología , Vaina de Mielina/patología , Oligodendroglía/efectos de los fármacos , Adulto , Animales , Anticuerpos Monoclonales/farmacología , Antígenos de Superficie/inmunología , Western Blotting , Muerte Celular/fisiología , Células Cultivadas , Activación de Complemento/efectos de los fármacos , Proteínas Inactivadoras del Complemento 1/farmacología , Complemento C3/fisiología , Proteínas del Sistema Complemento/fisiología , Técnica del Anticuerpo Fluorescente Indirecta , Humanos , Inmunoprecipitación , Microscopía Confocal , Esclerosis Múltiple/líquido cefalorraquídeo , Vaina de Mielina/efectos de los fármacos , Nervio Óptico/citología , Nervio Óptico/fisiología , Ratas , Ratas Sprague-Dawley , Células Madre/efectos de los fármacosRESUMEN
Activation of plasma prekallikein and generation of bradykinin are responsible for the angioedema attacks observed with C1-inhibitor deficiency. Heterozygous individuals with <50% levels of active C1-inhibitor are susceptible to angioedema attacks indicating a critical need for C1-inhibitor to be present at maximum levels to prevent unwanted prekallikrein activation. Studies with purified proteins do not adequately explain this observation. Therefore to investigate why reduction of C1-inhibitor to levels seen in angioedema patients results in excessive kallikrein generation we examined the effect of endothelial cells on the inhibition of kallikrein by C1-inhibitor. Surprisingly, it was found that a C1-inhibitor concentration of greater than 1 microM was needed to inhibit 3 nM kallikrein. We propose that this apparent protection from inhibition was mediated by kallikrein binding to the cells via the heavy chain in a high molecular weight kininogen and zinc independent manner. Protection of kallikrein from inhibition was not observed when C1-inhibitor truncated in the amino-terminal domain by the StcE metalloproteinase was used, which suggests a novel function for this unique domain. The requirement for high concentrations of C1-inhibitor to fully inhibit kallikrein is consistent with the fact that reduced levels of C1-inhibitor result in the kallikrein activation seen in angioedema.
Asunto(s)
Proteínas Inactivadoras del Complemento 1/biosíntesis , Proteínas Inactivadoras del Complemento 1/farmacología , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/metabolismo , Calicreínas/antagonistas & inhibidores , Calicreínas/sangre , Angioedema/sangre , Células Cultivadas , Cloro/metabolismo , Coagulantes/farmacología , Proteína Inhibidora del Complemento C1 , Relación Dosis-Respuesta a Droga , Electroforesis en Gel de Poliacrilamida , Endotelio Vascular/citología , Escherichia coli/metabolismo , Proteínas de Escherichia coli/metabolismo , Heterocigoto , Humanos , Calicreínas/metabolismo , Cinética , Metaloendopeptidasas/metabolismo , Estructura Terciaria de Proteína , Factores de Tiempo , Venas Umbilicales/citologíaRESUMEN
BACKGROUND: Because of current limitations in improving metabolic support to the brain during hypothermic circulatory arrest (HCA), attenuation of ischemia-reperfusion injury remains an area of therapeutic intervention of relevance. Apotransferrin (Apo-Tf), alpha 1-acid glycoprotein (AGP), and C1-esterase inhibitor (C1-INH) have been herein evaluated as potential beneficial agents in reducing the ischemia-reperfusion injury in a surviving model of HCA. METHODS: Apo-Tf 100 mg/kg (n = 6), C1-INH 50 IU/kg (n = 6), AGP 100 mg/kg (n = 6), or NaCl 0.9% 2 ml/kg (n = 6) were randomly administered to 24 juvenile pigs after a 75-min period HCA at a brain temperature of 18 degrees C. RESULTS: Animals in the Apo-Tf group had a slightly better 7-day survival (66.7%) compared with the other study groups (50%), but such a difference was not statistically significant. Some favorable changes in the brain glucose metabolism parameters were observed in the AGP, C1-INH, and Apo-Tf groups, but these did not reach statistical significance. Semiquantitative analysis of the histopathological findings did not show any significant difference between the study groups. However, only two out of four surviving animals in the Apo-Tf group developed brain infarction, whereas all three survivors of the remaining study groups developed brain infarction. CONCLUSIONS: Although the small size of the study groups may affect the present findings, none of the metabolic and hemodynamic parameters as well as outcome endpoints indicate a substantial therapeutic efficacy of Apo-Tf, AGP, and C1-INH as neuroprotective agents after experimental HCA.
Asunto(s)
Apoproteínas/farmacología , Infarto Encefálico/prevención & control , Circulación Cerebrovascular/efectos de los fármacos , Proteínas Inactivadoras del Complemento 1/farmacología , Hipotermia Inducida , Fármacos Neuroprotectores/farmacología , Orosomucoide/farmacología , Daño por Reperfusión/prevención & control , Transferrina/farmacología , Experimentación Animal , Animales , Apoproteínas/administración & dosificación , Infarto Encefálico/etiología , Proteínas Inactivadoras del Complemento 1/administración & dosificación , Femenino , Hemodinámica/efectos de los fármacos , Fármacos Neuroprotectores/administración & dosificación , Orosomucoide/administración & dosificación , Daño por Reperfusión/complicaciones , Porcinos , Transferrina/administración & dosificaciónRESUMEN
The serine protease inhibitor C1-Inhibitor (C1-Inh) inhibits several complement- and contact-system proteases, which play an important role in inflammation. C1-Inh has a short reactive site loop (RSL) compared to other serpins. RSL length determines the inhibitory activity of serpins. We investigated the effect of RSL elongation on inhibitory activity of C1-Inh by insertion of one or two alanine residues in the RSL. One of five mutants had an increased association rate with kallikrein, but was nevertheless a poor inhibitor because of a simultaneous high stoichiometry of inhibition (>10). The association rate of the other variants was lower than that of wild-type C1-Inh. These data suggest that the relatively weak inhibitory activity of C1-Inh is not the result of its short RSL. The short RSL of C1-Inh has, surprisingly, the optimal length for inhibition.