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1.
Nanomedicine ; 14(4): 1289-1299, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29627519

RESUMEN

Delayed wound healing is one of the hallmarks of diabetic complications and certain autoimmune inflammatory diseases. Extensive wound healing studies in rabbits have indicated that the delivery of ATP encapsulated in unilamellar nanoliposomes causes rapid cell proliferation and fast tracks the wound healing process. In the current study, we explored the possible molecular mechanism underlying this response by comparing gene expression in cultured rabbit kidney cells treated with either ATP nanoliposomes (containing 1 mg Mg-ATP/ml formulation) or control nanoliposomes (containing 1 mg/ml unmetabolisable gamma-thio-ATP/ml formulation). High-quality total RNA was isolated 24 h from the cells and subjected to RNA seq technology, which revealed significant overexpression of specific noncoding RNAs. The U1 spliceosomal RNA, U1 snRNA, was upregulated more than 250-fold following treatment with ATP nanoliposomes. This multifunctional U1 spliceosomal RNA may function in transcription by speeding up the critical splicing step, thereby facilitating faster processing of pre-mRNA to translatable mRNA.


Asunto(s)
Adenosina Trifosfato/metabolismo , ARN Mensajero/metabolismo , ARN Nuclear Pequeño/metabolismo , Empalmosomas/metabolismo , Animales , Conformación de Ácido Nucleico , Precursores del ARN/metabolismo , Empalme del ARN/genética , Empalme del ARN/fisiología , ARN Nuclear Pequeño/química , Conejos
2.
Wound Repair Regen ; 23(5): 724-7, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26053302

RESUMEN

Chronic wounds occurring during aging or diabetes pose a significant burden to patients. The classical four-phase wound healing process has a 3-6 day lag before granulation starts to appear and it requires an intermediate step of activation of resident fibroblasts during the remodeling phase for production of collagen. This brief communication discusses published articles that demonstrate how the entire wound healing process can be fast tracked by intracellular ATP delivery, which triggers a novel pathway where alternatively activated macrophages play absolutely critical and central roles. This novel pathway involves an increase in proinflammatory cytokines (TNF, IL-1ß, IL-6) and a chemokine (MCP-1) release. This is followed by activation of purinergic receptor (a family of plasma membrane receptors found in almost all mammalian cells), production of platelets and platelet microparticles, and activation of ATP-dependent chromatin remodeling enzymes. The end result is a massive influx and in situ proliferation of macrophages, increases in vascular endothelial growth factors that promote neovascularization, and most prominently, the direct production of collagen.


Asunto(s)
Adenosina Trifosfato/fisiología , Regeneración Tisular Dirigida/métodos , Macrófagos/metabolismo , Cicatrización de Heridas/fisiología , Heridas y Lesiones/metabolismo , Animales , Humanos , Heridas y Lesiones/patología
4.
Microrna ; 12(1): 22-28, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36200149

RESUMEN

BACKGROUND: Diabetic complications have been studied extensively in recent years. There are very few biomarkers in body fluids that can pinpoint a distinct diabetic complication due to insufficient known specific biomarkers for ischemia. OBJECTIVE: Identifying microRNA in animal models for each complication could enable early diagnosis of a given complication if verified in humans. MicroRNA (miRNA) profiling has been done in rodent models for a number of diabetic complications, like diabetic glomerular injury, atherosclerosis, cognitive impairment, diabetic wound healing, angiopathy and other complications. Due to multiple differences between rodents and humans, the changes in rabbit skin, considered closer to humans than even pigs, may better simulate human diabetic complications of ischemia. METHODS: To study the miRNA profile of rabbits in which diabetes was induced or ischemia was surgically generated, we studied whether diabetes or ischemia-induced specific miRNA could be detected. MicroRNA from the blood of diabetic rabbits and rabbits with local ischemia was collected in PAXgene Blood RNA tubes specifically designed for miRNA isolation and extracted using the PAX gene miRNA extraction kit. The isolated RNA was quality controlled using an RNA analyzer, and further, using RNA seq technology, it was analyzed for distinct miRNAs that were detected in diabetic and non-diabetic rabbits induced with ischemia. RESULTS: A miRNA that was found to be expressed in diabetic rabbits and ischemic rabbits but not in untreated rabbits was miRNA-183. Several miRNAs were differentially expressed across comparison groups, and several upregulated miRNAs were identified being unique to each comparison. In rabbits with a potential diabetic complication of a long-term ischemic model, there was one distinct microRNA, which was highly significantly upregulated in ischemia rabbit (miRNA-133-3p). One miRNA that was highly significantly upregulated in diabetic rabbit but not in ischemic rabbits was miRNA-3074-5p. Only statistically significant results have been considered and analyzed. CONCLUSION: These findings could lead to a precise and timely diagnosis of a potential single diabetic complication without invasive tissue biopsies and could be a novel tool in the management of diabetic patients developing complications due to the progression of diabetes.


Asunto(s)
Complicaciones de la Diabetes , Diabetes Mellitus , MicroARNs , Humanos , Conejos , Animales , Porcinos , MicroARNs/genética , Isquemia/genética , Isquemia/patología , Complicaciones de la Diabetes/genética , Biomarcadores , Perfilación de la Expresión Génica
5.
Nature ; 444(7116): 221-5, 2006 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-17051152

RESUMEN

The human complement system is an important component of innate immunity. Complement-derived products mediate functions contributing to pathogen killing and elimination. However, inappropriate activation of the system contributes to the pathogenesis of immunological and inflammatory diseases. Complement component 3 (C3) occupies a central position because of the manifold biological activities of its activation fragments, including the major fragment, C3b, which anchors the assembly of convertases effecting C3 and C5 activation. C3 is converted to C3b by proteolysis of its anaphylatoxin domain, by either of two C3 convertases. This activates a stable thioester bond, leading to the covalent attachment of C3b to cell-surface or protein-surface hydroxyl groups through transesterification. The cleavage and activation of C3 exposes binding sites for factors B, H and I, properdin, decay accelerating factor (DAF, CD55), membrane cofactor protein (MCP, CD46), complement receptor 1 (CR1, CD35) and viral molecules such as vaccinia virus complement-control protein. C3b associates with these molecules in different configurations and forms complexes mediating the activation, amplification and regulation of the complement response. Structures of C3 and C3c, a fragment derived from the proteolysis of C3b, have revealed a domain configuration, including six macroglobulin domains (MG1-MG6; nomenclature follows ref. 5) arranged in a ring, termed the beta-ring. However, because neither C3 nor C3c is active in complement activation and regulation, questions about function can be answered only through direct observations on C3b. Here we present a structure of C3b that reveals a marked loss of secondary structure in the CUB (for 'complement C1r/C1s, Uegf, Bmp1') domain, which together with the resulting translocation of the thioester domain provides a molecular basis for conformational changes accompanying the conversion of C3 to C3b. The total conformational changes make many proposed ligand-binding sites more accessible and create a cavity that shields target peptide bonds from access by factor I. A covalently bound N-acetyl-l-threonine residue demonstrates the geometry of C3b attachment to surface hydroxyl groups.


Asunto(s)
Activación de Complemento , Complemento C3b/química , Complemento C3b/metabolismo , Animales , Sitios de Unión , Cristalografía por Rayos X , Humanos , Modelos Moleculares , Conformación Proteica , Ratas , Relación Estructura-Actividad
6.
J Surg Res ; 159(2): 747-54, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19691975

RESUMEN

Renal transplantation is often confronted with ischemia reperfusion (I/R) injury that accounts for a delayed recovery of the graft. This surgically and biologically induced injury often results in activation of the complement system. The vaccinia virus complement control protein (VCP) down-regulates both the classical and alternative complement pathways by preventing the formation of C3b, a component where both pathways converge. The aim of the study was to investigate the effect of VCP on renal I/R injury. Long Evans rats were subjected to laparotomy, mobilization of the right kidney in unilateral ischemia, and both kidneys in bilateral ischemia. The renal arteries were clamped for 60 min followed by 24 h reperfusion time. The animals were randomly allocated to receive recombinant VCP (rVCP), natural VCP, and humanized recombinant VCP (hrVCP) combination, vehicle (PBS), or sham group. Blood samples were collected for biochemical studies, and the kidneys were removed for histopathologic and immunohistochemical studies. The biochemical studies in the bilateral ischemia showed that the PBS group displayed 1.5-fold and 5-fold increases in the urea and creatinine concentrations, respectively, compared with the VCP/hrVCP groups. In both models, the histopathologic study revealed focal necrosis of the tubular epithelial cells in the rVCP or VCP/hrVCP treated animals compared with the diffuse and markedly elevated field scores in the PBS controls. The immunohistochemical study showed significant C3 deposition in the renal tubules of the PBS controls compared with the rVCP or VCP/hrVCP groups, suggesting that rVCP, VCP/hrVCP reduced I/R injury by inhibiting the biosynthesis of C3.


Asunto(s)
Riñón/efectos de los fármacos , Daño por Reperfusión/prevención & control , Proteínas Virales/farmacología , Animales , Nitrógeno de la Urea Sanguínea , Vía Alternativa del Complemento/efectos de los fármacos , Vía Clásica del Complemento/efectos de los fármacos , Creatinina/sangre , Humanos , Riñón/patología , Riñón/fisiopatología , Trasplante de Riñón/efectos adversos , Masculino , Ratas , Ratas Long-Evans , Daño por Reperfusión/etiología , Daño por Reperfusión/patología , Daño por Reperfusión/fisiopatología
7.
Infect Immun ; 77(2): 725-32, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19047409

RESUMEN

The innate immune response is a double-edged sword in systemic inflammation and sepsis. Uncontrolled or inappropriate activation can damage and be lethal to the host. Several studies have investigated inhibition of downstream mediators, including tumor necrosis factor alpha (TNF-alpha) and interleukin-1beta (IL-1beta). Emerging evidence indicates that upstream inhibition is a better therapeutic approach for attenuating damaging immune activation. Therefore, we investigated inhibition of two central innate immune pathways, those of complement and CD14/Toll-like receptor 4 (TLR4)/myeloid differentiation protein 2 (MD-2), in a porcine in vitro model of Escherichia coli-induced inflammation. Porcine whole blood anticoagulated with lepuridin, which did not interfere with the complement system, was incubated with E. coli lipopolysaccharide (LPS) or whole bacteria. Inhibitors of complement and CD14 and thus the LPS CD14/TLR4/MD-2 receptor complex were tested to investigate the effect on the inflammatory response. A broad range of inflammatory readouts were used to monitor the effect. Anti-CD14 was found to saturate the CD14 molecule on granulocytes and completely inhibited LPS-induced proinflammatory cytokines in a dose-dependent manner. Anti-CD14 significantly reduced the levels of the E. coli-induced proinflammatory cytokines TNF-alpha and IL-1beta, but not IL-8, in a dose-dependent manner. No effect on bacterial clearance was seen. Vaccinia complement control protein and smallpox inhibitor of complement enzymes, two Orthopoxvirus-encoded complement inhibitors, completely inhibited complement activation. Furthermore, these agents almost completely inhibited the expression of wCD11R3, which is associated with CD18 as a beta2 integrin, on porcine granulocytes and decreased IL-8 levels significantly in a dose-dependent manner. As expected, complement inhibition reduced bacterial clearance. We conclude that inhibition of complement and CD14 attenuates E. coli-induced inflammation and might be used as a therapeutic regimen in gram-negative sepsis along with appropriate treatment with antibiotics.


Asunto(s)
Proteínas del Sistema Complemento/inmunología , Escherichia coli/fisiología , Inflamación/metabolismo , Receptores de Lipopolisacáridos/inmunología , Animales , Anticuerpos Monoclonales , Antígenos CD11/genética , Antígenos CD11/metabolismo , Citocinas/genética , Citocinas/metabolismo , Regulación de la Expresión Génica/inmunología , Granulocitos/metabolismo , Inmunidad Innata , Inflamación/sangre , Lipopolisacáridos/farmacología , Porcinos , Proteínas de la Matriz Viral/farmacología
8.
Front Pharmacol ; 10: 1502, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-32009945

RESUMEN

We have reported accelerated wound healing induced by intracellular ATP delivery in rabbits, through early massive accumulation, in situ proliferation, and M2 polarization of macrophages. Granulation tissue started to grow within first 24 h of treatment and continued the growth till the wound cavity is completely covered. However, the mechanisms underlying this macrophage response are totally unclear because no one has ever reported this before. In this study, we performed a preliminary exploration of the possible mechanisms by focusing on the roles of cytokines, growth factors, and stem cells in this process. Among the 33 adult rabbits, 18 were used for cytokine measurements and the remaining were used for histological and immunohistochemical studies. Four wounds were created on the ventral side of each ear. Two wounds on one side were treated with ATP-vesicles (10 mM ATP), and the other two were treated with controls (normal saline or Regranex). Dressing changes were made daily and the rabbits were sacrificed at 5 h, 12 h, and 1, 2, 3, 4, 6, 9, 15, and 26 days after wounding. Tissue samples were analyzed for cytokines and growth factors using real-time PCR and immunohistochemical staining. The control wounds showed an immediate increase in proinflammatory cytokines after wound creation but no further increase after this initial spike. The growth factor levels in the control wounds remained unchanged throughout the study. Conversely, the wounds treated with ATP-vesicles showed significantly higher expression of MCP-1 and stem cell markers (CD44, CD106, CD146, and CD34) at day 1, significantly higher IL-1ß and TNF-α expression from day 1-4, and significantly higher VEGF-A, VEGF-D, and VEGFR-2 expression from day 4-6 when compared to the controls. The significant upregulation of these factors corresponded to the very early and rapid macrophage accumulation, in situ proliferation, and M2 polarization, resulting in unprecedented rapid granulation tissue generation due to direct macrophage collagen production and neovascularization.

9.
Behav Brain Res ; 192(2): 173-7, 2008 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-18490064

RESUMEN

Vaccinia virus complement control protein (VCP) inhibits both the classical and alternate complement pathways. In diseases such as traumatic brain injury (TBI) and Alzheimer's disease (AD), pathological inflammation is caused by amongst several factors, prolonged or inappropriate activation of the complement system and is a significant cause of neurodegeneration. This study investigates for the first time the use of a cheeseboard maze to evaluate cognitive deficits and the effect of VCP on memory processes in 2- and 3-month-old mice that express mutant amyloid precursor protein (APPswe) and mutant presenilin 1 (Ps1dE9) that correspond to a form of early onset AD. A four-phase training schedule was carried out on the cheeseboard maze before intracranial injections of 5 microl of VCP (1.7 microg/microl) or 5 microl saline. Two weeks later the effect of VCP on memory was evaluated. A statistically significant decrease in goal latency in VCP-treated mice than saline-treated transgenic mice in both the first probe and reverse tasks was observed. Similarly, after a second intracranial VCP or saline injection performed 2 months later, the 6.5- and 7.5-month aged VCP-injected mice performed significantly better in goal latency in both second probe and reverse tasks than saline-treated mice. These data also demonstrated that the use of a dry maze is a sensitive technique for distinguishing cognitive measures between non-transgenic and APPswe/PS1De9 transgenic mice at a much earlier stage.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Modelos Animales de Enfermedad , Trastornos de la Memoria/tratamiento farmacológico , Memoria/efectos de los fármacos , Proteínas Virales/farmacología , Enfermedad de Alzheimer/fisiopatología , Enfermedad de Alzheimer/psicología , Precursor de Proteína beta-Amiloide/genética , Análisis de Varianza , Animales , Conducta Animal/efectos de los fármacos , Conducta Animal/fisiología , Diagnóstico Precoz , Conducta Exploratoria/efectos de los fármacos , Conducta Exploratoria/fisiología , Aprendizaje por Laberinto/efectos de los fármacos , Aprendizaje por Laberinto/fisiología , Memoria/fisiología , Trastornos de la Memoria/fisiopatología , Trastornos de la Memoria/psicología , Ratones , Ratones Transgénicos , Microinyecciones/métodos , Mutación , Presenilina-1/genética , Conducta Espacial/efectos de los fármacos , Conducta Espacial/fisiología , Factores de Tiempo , Resultado del Tratamiento , Proteínas Virales/administración & dosificación
10.
Mol Immunol ; 44(8): 1827-34, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17109963

RESUMEN

Therapeutic complement inhibition is a promising strategy for treatment of a number of diseases as judged from rodent studies. The species distance from rodents to humans may limit the clinical relevance of these studies. The pig is an alternative animal for studies of human diseases like sepsis and ischemia/reperfusion injury. However, available complement inhibitors for use in pigs are scarce. The aim of the present study was to investigate and compare the efficacy of selected candidate inhibitors of porcine complement in vitro for possible future application in vivo. Sera from three different pigs were each incubated with three different activators of the complement system (zymosan, heat-aggregated immunoglobulin G (HAIGG) and Escherichia coli). Three groups of complement inhibitor candidates were tested: serine protease inhibitors (FUT-175 and C1-inhibitor), monoclonal antibodies (anti-factor B (fB) and anti-factor D (fD)) and a recombinant regulatory protein (vaccinia virus complement control protein (VCP)). Read-out was the terminal C5b-9 complement complex (TCC). The serine protease inhibitors FUT-175 and C1-inhibitor dose-dependently inhibited TCC formation in zymosan-, HAIGG- and E. coli-activated porcine sera, but with different efficacy. Complete inhibition of TCC was obtained using 0.2 mg/mL FUT-175, but required 16 mg/mL of C1-inhibitor. The monoclonal anti-fB and -fD antibodies both inhibited TCC formation dose-dependently, but in different ways. Anti-fB at high dose (1 mg/mL) completely inhibited TCC formation in sera activated with zymosan and virtually completely in sera activated with HAIGG, but not in sera activated with E. coli. Anti-fD inhibited all three activators at low dose (0.05 mg/mL), and approximately 50% TCC reduction was obtained. The recombinant complement regulatory protein VCP efficiently and dose-dependently inhibited TCC formation with a complete inhibition found at 0.05 mg/mL for all three activators. All candidates tested inhibited porcine complement activation, but in different ways and to different degrees. Of the complement-specific candidates, VCP inhibited all activators completely at low doses.


Asunto(s)
Activación de Complemento/efectos de los fármacos , Inactivadores del Complemento/farmacología , Complejo de Ataque a Membrana del Sistema Complemento/química , Animales , Inactivadores del Complemento/química , Relación Dosis-Respuesta a Droga , Roedores , Porcinos
11.
Brain Res ; 1153: 158-65, 2007 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-17467672

RESUMEN

Vaccinia virus complement control protein (VCP) is an immunomodulator that inhibits both the classical and alternate pathways of the complement system, therefore preventing cell death and inflammation. VCP has previously been shown to be therapeutically effective in mild and moderate traumatic brain injury models. In this study the efficacy of VCP in a severe head injury model is investigated in Wistar rats. Training in a Morris Water Maze (MWM) commenced 2 days prior stereotaxic surgery. Rats were anesthetized before being subjected to a severe (2.7-3.0 atm) lateral fluid percussion injury (FPI) 3.0 mm lateral to the sagittal suture and 4.5 mm posterior to bregma. Ten microliters of VCP (1.7 microg/microl) was injected into the injury site immediately after FPI. Fourteen days post-FPI, rats were tested for spatial learning and memory using the Morris Water Maze, followed by a battery of sensorimotor tests. The latter tests showed statistically significant differences between saline-treated and VCP-treated rats in lateral left pulsion (p=0.001) and tactile placing (p=0.002) on the first 5 days of testing. In addition, significant differences in right lateral pulsion in the first 4 days (p=0.007) of testing was evident. The results suggest that in a severe head injury model, VCP at this dosage favorably influences sensorimotor outcome.


Asunto(s)
Traumatismos Craneocerebrales/tratamiento farmacológico , Traumatismos Craneocerebrales/fisiopatología , Actividad Motora/efectos de los fármacos , Recuperación de la Función/efectos de los fármacos , Proteínas Virales/uso terapéutico , Análisis de Varianza , Animales , Modelos Animales de Enfermedad , Gliosis/tratamiento farmacológico , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Examen Neurológico/métodos , Pruebas Neuropsicológicas , Ratas , Ratas Wistar , Índices de Gravedad del Trauma
12.
Results Probl Cell Differ ; 62: 353-364, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28455716

RESUMEN

Chronic wounds pose considerable public health challenges and burden. Wound healing is known to require the participation of macrophages, but mechanisms remain unclear. The M1 phenotype macrophages have a known scavenger function, but they also play multiple roles in tissue repair and regeneration when they transition to an M2 phenotype. Macrophage precursors (mononuclear cells/monocytes) follow the influx of PMN neutrophils into a wound during the natural wound-healing process, to become the major cells in the wound. Natural wound-healing process is a four-phase progression consisting of hemostasis, inflammation, proliferation, and remodeling. A lag phase of 3-6 days precedes the remodeling phase, which is characterized by fibroblast activation and finally collagen production. This normal wound-healing process can be accelerated by the intracellular delivery of ATP to wound tissue. This novel ATP-mediated acceleration arises due to an alternative activation of the M1 to M2 transition (macrophage polarization), a central and critical feature of the wound-healing process. This response is also characterized by an early increased release of pro-inflammatory cytokines (TNF, IL-1 beta, IL-6), a chemokine (MCP-1), an activation of purinergic receptors (a family of plasma membrane receptors found in almost all mammalian cells), and an increased production of platelets and platelet microparticles. These factors trigger a massive influx of macrophages, as well as in situ proliferation of the resident macrophages and increased synthesis of VEGFs. These responses are followed, in turn, by rapid neovascularization and collagen production by the macrophages, resulting in wound covering with granulation tissue within 24 h.


Asunto(s)
Diferenciación Celular/inmunología , Macrófagos/citología , Cicatrización de Heridas/inmunología , Animales , Humanos , Macrófagos/inmunología
13.
Biochim Biophys Acta ; 1650(1-2): 30-9, 2003 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-12922167

RESUMEN

The vaccinia virus complement control protein (VCP) is involved in modulating the host inflammatory response by blocking both pathways of complement activity through its ability to bind C3b and C4b. Other activities arise from VCP's ability to strongly bind heparin. To map regions within VCP involved in binding complement and heparin experimentally, surface plasmon resonance (SPR) and recombinantly expressed VCP (rVCP) constructs were employed. Using C3b or heparin as the immobilized ligand, various rVCP constructs were tested for their ability to bind. Results suggest that VCP is the smallest functional unit able to bind C3b, thereby blocking complement activity, and only a single site, the large basic region near the C-terminus, is involved in heparin binding. Kinetic analysis was also performed to determine the relative binding affinities between rVCP and complement (C3-MA and C4b), as well as rVCP and heparin. rVCP was found to possess a significantly greater affinity for C3-MA than C4b, as indicated by the 1.50e3-fold greater association rate constant (k(a)). This study provides insights for the design of new therapeutic proteins capable of blocking complement activation.


Asunto(s)
Proteínas del Sistema Complemento/metabolismo , Heparina/metabolismo , Virus Vaccinia/metabolismo , Proteínas Virales/metabolismo , Sitios de Unión , Relación Dosis-Respuesta a Droga , Proteínas Recombinantes/metabolismo , Resonancia por Plasmón de Superficie , Factores de Tiempo , Levaduras/metabolismo
14.
Biochim Biophys Acta ; 1598(1-2): 55-64, 2002 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-12147344

RESUMEN

Vaccinia virus complement control protein (VCP) possesses the ability to inhibit both classical and alternative pathways of complement activation, as well as bind to heparin or heparan sulfate proteoglycans, making it a unique multifunctional protein with therapeutic potential. Recently, the structure of the complete molecule of VCP was determined by X-ray crystallography. Two or three VCP molecules were packed within the unit cells of both crystal forms. Using gel filtration, VCP has now been shown to exist as a monomer in solution. To test the stability of this molecule, VCP was studied by nuclear magnetic resonance (NMR) over a range of temperatures and by differential scanning calorimetry (DSC). It was also subjected to adverse physical conditions, including, freeze-thawing, changes in pH, changes in temperature, and storage at room temperature. VCP melts fully reversibly, and it maintained its 3-D structure and the ability to inhibit serum-induced hemolysis of sheep red blood cells after exposure to many extreme conditions. The robustness of VCP may be rationalized in terms of its architecture.


Asunto(s)
Virus Vaccinia/química , Proteínas Virales/química , Animales , Rastreo Diferencial de Calorimetría , Congelación , Hemólisis/efectos de los fármacos , Espectroscopía de Resonancia Magnética , Conformación Proteica , Proteínas Recombinantes/química , Ovinos , Termodinámica , Proteínas Virales/farmacología
15.
Ann N Y Acad Sci ; 1056: 55-68, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16387677

RESUMEN

The main objective of this study was to investigate the therapeutic efficiency of recombinant vaccinia virus complement control protein (rVCP) on collagen-induced arthritis (CIA) in DBA-1/J mice. Arthritis was induced in DBA-1J mice by injecting bovine collagen emulsified in complete Freunds adjuvant. We used rVCP to block complement activation and investigated its effect on different aspects of CIA including osteoclast formation and bone destruction. The osteoclast-like cells were detected using immunohistochemistry. Joint destruction was studied using X-ray of the intact knee joints. Cartilage destruction was monitored by staining the paraffin sections with toluidine blue. ELISA was used to measure the cytokine levels in the serum. Blocking complement activation in DBA/1J arthritic mice with rVCP resulted in significant inhibition of the clinical progression of the disease and reduction in joint destruction as revealed by X-ray analysis and toluidine blue staining of the joint sections. Inhibition of complement reduced the production of proinflammatory cytokines and the number of osteoclast-like cells in arthritic joints. In conclusion, blocking of complement in CIA by rVCP inhibits the inflammation and the formation of osteoclast-like cells and reduces cartilage destruction.


Asunto(s)
Artritis/inducido químicamente , Artritis/tratamiento farmacológico , Proteínas Virales/uso terapéutico , Animales , Artritis/patología , Artritis/fisiopatología , Colágeno , Modelos Animales de Enfermedad , Inflamación/prevención & control , Inyecciones Intraperitoneales , Masculino , Ratones , Ratones Endogámicos DBA , Proteínas Recombinantes/uso terapéutico , Proteínas Virales/administración & dosificación , Proteínas Virales/genética
16.
Ann N Y Acad Sci ; 1056: 100-12, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16387680

RESUMEN

Curcumin (Cur), the golden yellow phenolic compound in turmeric, is well studied for its medicinal properties. In the current investigation, Cur dissolved using sodium hydroxide solution (CurNa) was tested for in vitro complement inhibitory activity and compared with rosmarinic acid (RA) and quercetin (Qur) dissolved using sodium hydroxide (RANa and QurNa, respectively) and the vaccinia virus complement control protein (VCP). The comparative study indicated that CurNa inhibited the classical complement pathway dose dependently (IC50 = 404 microM). CurNa was more active than RANa, but less active than QurNa. VCP was about 2,212, 2,786, and 4,520 times more active than QurNa, CurNa, and RANa, respectively. Further study revealed that CurNa dose dependently inhibited zymosan-induced activation of the alternate pathway of complement activation.


Asunto(s)
Vía Alternativa del Complemento/efectos de los fármacos , Vía Clásica del Complemento/efectos de los fármacos , Curcumina/farmacología , Análisis de Varianza , Cinamatos/farmacología , Depsidos/farmacología , Hemólisis/efectos de los fármacos , Humanos , Quercetina/farmacología , Proteínas Virales/farmacología , Ácido Rosmarínico
17.
Ann N Y Acad Sci ; 1056: 113-22, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16387681

RESUMEN

Vaccinia virus complement control protein (VCP) is able to modulate the host complement system by regulating both pathways of complement activation. Efficient downregulation of complement activation depends on the ability of the regulatory protein to effectively bind the activated third (C3b) and fourth (C4b) complement components. Based on native crystallographic structure, molecular modeling, and sequence alignment with other Orthopoxviral complement control proteins (CCPs) and their host homologs, putative sites have been found on VCP as contact points for C3b/C4b. Here, we report that using site-directed mutagenesis, modified proteins have been generated. In addition, we report that the generated modified proteins with postulated contact point substitutions have shown greater ability to regulate both the classical and the alternative pathways of complement activation than the recombinant Western Reserve VCP, with one modified protein showing nearly 100-fold more potency in regulating both complement activation pathways independently. The augmented in vitro inhibitory activity of the modified protein together with the newly created putative heparin binding site suggests its promising potential as a competent therapeutic agent in modulating various complement-mediated ailments, for example, traumatic brain injury, Alzheimer's disease, rheumatoid arthritis, multiple organ dysfunction syndrome, reperfusion injury, and xenorejection.


Asunto(s)
Vía Alternativa del Complemento/efectos de los fármacos , Vía Clásica del Complemento/efectos de los fármacos , Heparina/metabolismo , Proteínas Virales/farmacología , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Sitios de Unión , Clonación Molecular , Humanos , Cinética , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacología , Proteínas Virales/química
18.
Ann N Y Acad Sci ; 1056: 303-10, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16387697

RESUMEN

The plant extract Secomet-V has previously been shown by Kotwal et al. to have potent antiviral activity. It was tested for mutagenicity with the Ames gene mutation test in Salmonella and the chromosome damage (clastogenic) micronucleolus (MN) test in human lymphocytes. These tests predict long-term carcinogenesis activity of the agents tested. Secomet-V (with charcoal added) demonstrated weak clastogenic activity, but powerful mutagenic activity in the Ames test with the addition of exogenous metabolic activation. The mutagenic activity of the conventional antiretroviral drugs AZT, Didanosine (DID), and 3TC alone and in dual combinations was also assessed for the first time for Salmonella mutagenicity without any mutagenic effects. AZT, DID, and 3TC have also been tested for MN induction; DID and 3TC resulted negatively, whereas AZT was positive in a dose-related manner. The dual combinations of AZT and DID, 3TC and DID plus 3TC did not result in any additive or synergistic effect. Purification in the absence of charcoal results in a drastic reduction in extract mutagenicity, which is almost reduced completely by further ultrafiltration (cutoff <3,000 Da). This fraction, which is a mixture of molecules of less than 3,000 Da, still possesses the capability to induce sister chromatid exchanges in human lymphocytes. This could be due to residual mutagenicity or, more likely, to the slowdown of the DNA replication process. These findings open new possibilities for HIV therapy, because this antiviral activity of Secomet-V purified in the absence of charcoal and further filtered through a 3,000-Da filter is devoid of mutagenic activity and therefore safe for long-term use.


Asunto(s)
Antivirales/farmacología , Didanosina/toxicidad , Lamivudine/toxicidad , Extractos Vegetales/farmacología , Trifolium , Zidovudina/toxicidad , Fármacos Anti-VIH/toxicidad , Pruebas de Mutagenicidad , Fitoterapia , Salmonella/efectos de los fármacos , Salmonella/genética
19.
Ann N Y Acad Sci ; 1056: 413-29, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16387706

RESUMEN

The upregulated complement system plays a damaging role in disorders of the central nervous system (CNS). The classical and alternate pathways are two major pathways activated in neuroinflammatory disorders such as Alzheimer's disease, multiple sclerosis, traumatic brain injury, spinal cord injury, HIV-associated dementia, Parkinson's disease, and mad cow disease. Failure of currently available anti-inflammatory agents, especially cyclooxygenase inhibitors, in offering significant neuroprotection in large epidemiologic clinical trials of CNS disorders suggests an urgent need for the development of new neuroprotective agents. The positive preclinical outcomes in treating CNS disorders by complement regulatory molecules, such as vaccinia virus complement control protein, suggest the possibility of using complement-inhibitory molecules as neuroprotective agents. Several active ingredients of herbal origin are found to have complement-inhibitory activity. These herbal ingredients along with other anti-inflammatory roles might be useful in treating neuroinflammation associated with CNS disorders. Active ingredients of herbal origin with complement inhibitory ingredients are summarized and classified according to their chemical nature and specificity towards the major pathways activating the complement system. The structure activity relationship of some specific examples is also discussed in this report. This information might be helpful in formulating a natural panacea against complement-mediated neuroinflammation.


Asunto(s)
Inactivadores del Complemento/farmacología , Enfermedades del Sistema Nervioso/tratamiento farmacológico , Inflamación Neurogénica/tratamiento farmacológico , Extractos Vegetales/farmacología , Plantas Medicinales , Humanos , Extractos Vegetales/clasificación , Plantas Medicinales/clasificación
20.
Ann N Y Acad Sci ; 1056: 450-61, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16387708

RESUMEN

Previous studies have shown that traumatic mild brain injury in a rat model is accompanied by breakdown of the blood brain barrier and the accumulation of inflammatory cells. A therapeutic agent, vaccinia virus complement control protein (VCP), inhibits both the classic and the alternative pathways of the complement system and, in so doing, prevents cell death and inflammation. With the use of a rat mild injury model, the effects of VCP on spatial learning and memory were tested. Training in a Morris water maze consisted of a total of 16 trials over a 2-day period before rats were anesthetized and subjected to mild (1.0-1.1 atm) lateral fluid percussion injury (FPI) 3.0 mm lateral to the sagittal suture and 4.5 mm posterior to bregma. Ten microl of VCP (1.7 mg/ml) was injected into the injury site immediately after FPI. Two weeks post-FPI the rats were assessed in the Morris water maze for spatial learning and memory. Neurologic motor function tests were carried out after FPI for 14 consecutive days and again after 28 days. The Morris water maze data show that FPI plus saline-injected rats spent a significantly (P <0.05) larger amount of time in one of the incorrect quadrants than did the FPI plus VCP-injected group. Neurologic evaluations 24 hours postinjury revealed differences in sensorimotor function between groups. The results suggest that in a mild injury model, VCP influences neurologic outcome and offers some enhancement in spatial memory and learning.


Asunto(s)
Proteínas Virales/uso terapéutico , Heridas y Lesiones/tratamiento farmacológico , Animales , Aprendizaje por Laberinto/efectos de los fármacos , Memoria , Modelos Animales , Ratas , Percepción Espacial
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