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1.
Am J Physiol Renal Physiol ; 315(6): F1732-F1746, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30280601

RESUMO

In a previous study of fungal peritoneal injury in peritoneal dialysis patients, complement (C)-dependent pathological changes were developed in zymosan (Zy)-induced peritonitis by peritoneal scraping. However, the injuries were limited to the parietal peritoneum and did not show any fibrous encapsulation of the visceral peritoneum, which differs from human encapsular peritoneal sclerosis (EPS). We investigated peritoneal injury in a rat model of Zy-induced peritonitis pretreated with methylglyoxal (MGO) instead of scraping (Zy/MGO peritonitis) to clarify the role of C in the process of fibrous encapsulation of the visceral peritoneum. Therapeutic effects of an anti-C5a complementary peptide, AcPepA, on peritonitis were also studied. In Zy/MGO peritonitis, peritoneal thickness, fibrin exudation, accumulation of inflammatory cells, and deposition of C3b and C5b-9 with loss of membrane C regulators were increased along the peritoneum until day 5. On day 14, fibrous encapsulation of the visceral peritoneum was observed, resembling human EPS. Peritoneal injuries and fibrous changes were significantly improved with AcPepA treatment, even when AcPepA was administered following injection of Zy in Zy/MGO peritonitis. The data show that C5a might play a role in the development of encapsulation-like changes in the visceral peritoneum in Zy/MGO peritonitis. AcPepA might have therapeutic effects in fungal infection-induced peritoneal injury by preventing subsequent development of peritoneal encapsulation.


Assuntos
Ativação do Complemento/efeitos dos fármacos , Complemento C5a/antagonistas & inibidores , Inativadores do Complemento/farmacologia , Fibrose Peritoneal/prevenção & controle , Peritônio/efeitos dos fármacos , Aldeído Pirúvico , Zimosan , Animais , Complemento C5a/imunologia , Modelos Animais de Doenças , Progressão da Doença , Masculino , Fibrose Peritoneal/induzido quimicamente , Fibrose Peritoneal/imunologia , Fibrose Peritoneal/patologia , Peritônio/imunologia , Peritônio/patologia , Peritonite/induzido quimicamente , Peritonite/imunologia , Peritonite/metabolismo , Peritonite/patologia , Ratos Sprague-Dawley , Índice de Gravidade de Doença , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo
2.
Surgery ; 159(3): 960-71, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26632492

RESUMO

BACKGROUND: Nonocclusive mesenteric ischemia (NOMI) can evolve in a variety of low-flow states. Although the mechanisms leading to NOMI-related intestinal necrosis are largely unknown, circumstantial evidence suggests that excessive vasoconstriction and complement activation both play important roles in this process. Because targeting of the circulatory malfunction of the splanchnic area could be of therapeutic relevance, we set out to investigate the long-term effects of treatment with a complement C5a antagonist in a rat model of partial aortic occlusion (PAO)-induced transient mesenteric hypoperfusion. METHODS: The mean arterial pressure of the splanchnic area was kept between 30 and 40 mm Hg by 60 minutes of PAO in anesthetized male Sprague-Dawley rats. C5a inhibitor acetyl-peptide-A (AcPepA; 4 mg kg(-1) intravenously) or vehicle administration was initiated at the 45th minute of PAO. After 24 hours, the animals were reanesthetized to record the macrohemodynamics and ileal microcirculation, and plasma and tissue samples were taken for determination of high-mobility group box protein-1 (HMGB-1), endothelin-1, tumor necrosis factor (TNF)-α levels, and small intestinal leukocyte infiltration. Epithelial structural changes were visualized by in vivo confocal laser scanning endomicroscopy. RESULTS: At 24 hours after PAO, mean arterial pressure, heart rate, and cardiac output were significantly greater, the intestinal intramural microcirculation was significantly impaired, and plasma HMGB-1, endothelin-1, TNF-α levels, the degree of epithelial damage and leukocyte infiltration was increased. The AcPepA treatment moderated the hemodynamic and microcirculatory changes, and decreased inflammatory activation and histologic signs of mucosal damage. CONCLUSION: C5a inhibition ameliorated the potentially harmful local mesenteric hypoperfusion and global long-term inflammatory consequences of PAO. This approach is of promise for use in NOMI-associated situations.


Assuntos
Hemodinâmica/efeitos dos fármacos , Íleo/irrigação sanguínea , Inflamação/sangue , Isquemia Mesentérica/tratamento farmacológico , Serina Endopeptidases/farmacologia , Análise de Variância , Animais , Biomarcadores/sangue , Modelos Animais de Doenças , Endotelina-1/sangue , Proteína HMGB1/sangue , Hemodinâmica/fisiologia , Inflamação/fisiopatologia , Masculino , Isquemia Mesentérica/patologia , Microcirculação/efeitos dos fármacos , Microscopia de Vídeo , Análise Multivariada , Projetos Piloto , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Estatísticas não Paramétricas , Fator de Necrose Tumoral alfa/sangue , Grau de Desobstrução Vascular/efeitos dos fármacos
3.
Microbiol Immunol ; 60(1): 47-55, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26616436

RESUMO

Performance status (PS) frequently improves occurs in cancer patients who have been infused with their own lymphokine-activated killer T cells (LAK-T). In the present study, a culture supernatant of LAK-T (LAK-T sup) administered to 8-week-old rats caused neurogenesis as evidenced by increased 5-ethynyl-2'-deoxyuridine staining of brain tissues. Intravenous injection of granulocyte-macrophage colony stimulating factor (GM-CSF), a major cytokine in LAK-T sup, had a similar effect. Furthermore, LAK-T sup induced Ca(++) increase in rat hippocampal brain slices that was detected in neuronal cells by emission of Fluo-8 NW at 520 nm. The same effect was observed with an rGM-CSF solution. GM-CSF may activate neuronal cells by stimulating the glial cells that surround and attach to them. If so, GM-CSF and LAK-T sup may improve the motor neurons of patients with amyotrophic lateral sclerosis. The neurogenerative effect of GM-CSF in LAK-T sup may also help improve brain function in aged adults including those with dementia such as Alzheimer's disease.


Assuntos
Anticorpos Monoclonais/farmacologia , Interleucina-2/farmacologia , Células Matadoras Ativadas por Linfocina/imunologia , Neurônios/imunologia , Linfócitos T Citotóxicos/efeitos dos fármacos , Adulto , Doença de Alzheimer/terapia , Esclerose Lateral Amiotrófica/terapia , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/imunologia , Encéfalo/patologia , Proliferação de Células/fisiologia , Citocinas/imunologia , Citometria de Fluxo , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Humanos , Imunoterapia Adotiva/métodos , Interleucina-2/imunologia , Células Matadoras Ativadas por Linfocina/citologia , Células Matadoras Ativadas por Linfocina/efeitos dos fármacos , Células Matadoras Ativadas por Linfocina/transplante , Masculino , Neurogênese/imunologia , Neurônios/citologia , Neurônios/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Ratos Wistar , Linfócitos T Citotóxicos/imunologia , Regulação para Cima
4.
Microbiol Immunol ; 60(1): 35-46, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26576826

RESUMO

Acute mesenteric ischemia (AMI) is caused by considerable intestinal injury, which is associated with intestinal ischemia followed by reperfusion. To elucidate the mechanisms of ischemia/reperfusion injuries, a C5a inhibitory peptide termed AcPepA was used to examine the role of C5a anaphylatoxin, induction of inflammatory cells, and cell proliferation of the intestinal epithelial cells in an experimental AMI model. In this rat model, the superior mesenteric artery was occluded and subsequently reperfused (Induce-I/R). Other groups were treated with AcPepA before ischemia or reperfusion. Induce-I/R induced injuries in the intestine and AcPepA significantly decreased the proportion of severely injured villi. Induce-I/R induced secondary receptor for C5a-positive polymorphonuclear leukocytes in the vessels and CD204-positive macrophages near the injured site; this was correlated with hypoxia-induced factor 1-alpha-positive cells. Induction of these inflammatory cells was attenuated by AcPepA. In addition, AcPepA increased proliferation of epithelial cells in the villi, possibly preventing further damage. Therefore, Induce-I/R activates C5a followed by the accumulation of polymorphonuclear leukocyte and hypoxia-induced factor 1-alpha-producing macrophages, leading to villus injury. AcPepA, a C5a inhibitory peptide, blocks the deleterious effects of C5a, indicating it has a therapeutic effect on the inflammatory consequences of experimental AMI.


Assuntos
Enteropatias/prevenção & controle , Intestino Delgado/irrigação sanguínea , Receptor da Anafilatoxina C5a/antagonistas & inibidores , Traumatismo por Reperfusão/prevenção & controle , Serina Endopeptidases/farmacologia , Animais , Antígenos CD/imunologia , Antígenos de Diferenciação Mielomonocítica/imunologia , Proliferação de Células , Subunidade alfa do Fator 1 Induzível por Hipóxia/imunologia , Imuno-Histoquímica , Mucosa Intestinal/patologia , Intestino Delgado/patologia , Masculino , Neutrófilos , Ratos , Ratos Sprague-Dawley , Receptor da Anafilatoxina C5a/imunologia , Fator de Necrose Tumoral alfa/imunologia
5.
Am J Physiol Renal Physiol ; 305(11): F1603-16, 2013 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-23904221

RESUMO

In peritoneal dialysis (PD) therapy, physical stresses such as exposure to peritoneal dialysate, catheter trauma, and peritonitis may induce peritoneal injury that can prevent continued long-term PD therapy. Therefore, protection of the peritoneum is an important target to enable long-term PD therapy in patients with end-stage renal disease. We previously showed that neutralization of the membrane complement regulators (CRegs) Crry and CD59 in rat peritoneum provokes development of acute peritoneal injury due to uncontrolled complement activation. C5a is a key effecter molecule of the complement system released during acute inflammation. Control of C5a has been proposed as a strategy to suppress inflammatory reactions and, because peritoneal injury is accompanied by inflammation, we hypothesized that C5a targeted therapy might be an effective way to suppress peritoneal injury. In the present study we used an established acute peritonitis model induced by neutralization of CRegs to investigate the effects on acute peritoneal injury of inhibiting C5a. Intravenous administration of an anti-C5a complementary peptide (AcPepA) up to 4 h after induction of injury significantly and dose-dependently prevented accumulation of inflammatory cells and reduced tissue damage in the model, accompanied by decreased C3b deposition. We show that C5a contributed to the development of peritoneal injury. Our results suggest that C5a is a target for preventing or treating peritoneal injury in patients undergoing prolonged PD therapy or with infectious complications.


Assuntos
Anticorpos/uso terapêutico , Antígenos de Protozoários/imunologia , Antígenos de Superfície/imunologia , Antígenos de Superfície/metabolismo , Antígenos CD59/metabolismo , Peritônio/efeitos dos fármacos , Peritonite/tratamento farmacológico , Receptores de Superfície Celular/metabolismo , Animais , Anticorpos/imunologia , Ativação do Complemento/efeitos dos fármacos , Ativação do Complemento/imunologia , Modelos Animais de Doenças , Masculino , Fragmentos de Peptídeos/imunologia , Fragmentos de Peptídeos/farmacologia , Diálise Peritoneal/métodos , Peritônio/imunologia , Peritônio/lesões , Peritonite/induzido quimicamente , Peritonite/imunologia , Ratos , Ratos Sprague-Dawley
6.
Crit Care Med ; 41(11): e344-51, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23949471

RESUMO

OBJECTIVE: Cardiogenic shock often leads to splanchnic macro- and microcirculatory complications, and these events are linked to local and systemic inflammatory activation. Our aim was to investigate the consequences of complement C5a antagonist treatment on the early circulatory and inflammatory changes in a clinically relevant large animal model of cardiac tamponade. DESIGN AND SETTING: A randomized, controlled in vivo animal study in a university research laboratory. SUBJECTS: Anesthetized, ventilated, and thoracotomized Vietnamese mini pigs (24 ± 3 kg). INTERVENTIONS: Group 1 (n = 6) served as sham-operated control. In group 2 (n = 7), cardiac tamponade was induced for 60 minutes by the administration of intrapericardial fluid, while the mean arterial pressure was kept in the interval 40 to 45 mm Hg. Group 3 (n = 6) was treated with a complement C5a antagonist compound (the peptide acetyl-peptide-A, 4 mg/kg) after 45 minutes of tamponade. MEASUREMENTS AND MAIN RESULTS: The macrohemodynamics, including the superior mesenteric artery flow, was monitored; the average red blood cell velocity in the small intestinal mucosa was determined by an intravital orthogonal polarization imaging technique. The whole blood superoxide production, the plasma level of high-mobility group box protein-1 and big-endothelin and the small intestinal myeloperoxidase activity were measured. One hundred eighty minutes after the relief of tamponade, the mean arterial pressure was decreased, while the plasma levels of superoxide, high-mobility group box protein-1, and big-endothelin, and the intestinal myeloperoxidase activity were increased. The administration of acetyl-peptide-A normalized the mean arterial pressure and preserved the cardiac output, while the superior mesenteric artery flow and mucosal average red blood cell velocity were increased significantly, and the plasma superoxide, high-mobility group box protein-1, big-endothelin, and intestinal myeloperoxidase levels were reduced. CONCLUSIONS: These results provide evidence that blockade of the C5a effects significantly influences the acute splanchnic macro- and microhemodynamic complications and decreases the potentially harmful inflammatory consequences of experimental cardiogenic shock.


Assuntos
Tamponamento Cardíaco/terapia , Complemento C5a/antagonistas & inibidores , Peptídeos/farmacologia , Animais , Tamponamento Cardíaco/fisiopatologia , Modelos Animais de Doenças , Endotelina-1/metabolismo , Feminino , Proteína HMGB1/metabolismo , Hemodinâmica , Histamina/sangue , Mucosa Intestinal/irrigação sanguínea , Masculino , Microcirculação , Distribuição Aleatória , Superóxidos/metabolismo , Suínos
7.
Pediatr Res ; 72(6): 600-5, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23041664

RESUMO

BACKGROUND: Oxidative stress (oxidant-antioxidant imbalance) plays an important role in the pathophysiology of neonatal sepsis. This study evaluated whether an antisense peptide endothelin receptor antagonist, ETR-P1/fl, could attenuate oxidative stress in a neonatal sepsis model. METHODS: A total of 18 3-d-old piglets were anesthetized and mechanically ventilated. Six piglets received cecal ligation and perforation (CLP group) for induction of sepsis. Six piglets also received continuous infusion (0.05 mg/kg/h) of ETR-P1/fl 30 min after CLP (ETR-P1/fl group). Six piglets received a sham operation. Serum total hydroperoxide (TH), biological antioxidant potentials (BAPs), oxidative stress index (OSI, calculated as TH/BAP), interleukin (IL)-6, serum glutamic oxaloacetic transaminase (GOT), and creatinine were measured before CLP and at 1, 3, and 6 h after CLP. RESULTS: CLP evoked a state of shock resulting in elevated TH, OSI, and IL-6 levels. ETR-P1/fl administration after CLP resulted in lower serum TH at 1 and 3 h after CLP, OSI at 1 and 3 h after CLP, IL-6 at 1 and 3 h after CLP, and GOT at 3 and 6 h after CLP as compared with the CLP group. CONCLUSION: ETR-P1/fl treatment significantly attenuated the elevation of serum oxidative stress markers (TH and OSI), IL-6, and GOT in a progressive neonatal sepsis CLP model.


Assuntos
Antagonistas dos Receptores de Endotelina , Estresse Oxidativo/efeitos dos fármacos , Peptídeos/farmacologia , Animais , Aspartato Aminotransferases/sangue , Creatinina/sangue , Peróxido de Hidrogênio/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular , Interleucina-6/metabolismo , Suínos
8.
Allergol Int ; 61(4): 559-62, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23093794

RESUMO

This guideline was provided by the Japanese Association for Complement Research targeting clinicians for making an accurate diagnosis of hereditary angioedema (HAE), and for prompt treatment of the HAE patient in Japan. This is a 2010 year version and will be updated according to any pertinent medical advancements.


Assuntos
Angioedemas Hereditários/diagnóstico , Angioedemas Hereditários/terapia , Humanos
9.
Neurochem Int ; 60(6): 631-9, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22406418

RESUMO

Complement C5a is associated primarily with inflammation. The widespread expression of its receptors, C5aR and C5L2 in neuronal cells, however, suggests additional regulatory roles for C5a in the CNS. C5aR agonist (PL37-MAP) evokes Ca(2+)-influx in GT1-7 neuronal cell line and the Ca(2+)-influx is regulated by estradiol. In the present study, we examined further the mechanism of Ca(2+)-influx and the contribution of the two estrogen receptor (ER) isotypes, ERα and ERß, to estrogenic modulation of intracellular Ca(2+)-content. GT1-7 neurons were treated with isotype selective ER agonists for 24h then C5aR agonist evoked Ca(2+)-responses were measured by Ca(2+)-imaging. Transcriptional changes were followed by real-time PCR. We found that not only estradiol (100 pM), but the ERα selective agonist PPT (100 pM) enhanced the PL37-MAP-evoked Ca(2+)-influx (E2: 215%, PPT: 175%, compared to the PL37-MAP-evoked Ca(2+)-influx). In contrast, the ERß selective agonist DPN (100 pM) significantly reduced the Ca(2+)-influx (32%). Attenuated Ca(2+)-response (25%) was observed in Ca-free environment and depletion of the Ca(2+)-pool by CPA eliminated the remaining elevation in the Ca(2+)-content, demonstrating that the majority of Ca(2+) originated from the extracellular compartment. L-type voltage-gated Ca(2+)-channel (L-VGCC) blocker nifedipine abolished the Ca(2+)-influx, while R-type Ca(2+)-channel blocker SNX-482 had no effect, exemplifying the predominant role of L-VGCC in this process. Acute pre-treatments (8 min) with ER agonists did not affect the evoked Ca(2+)-influx, revealing that the observed effects of estrogens were genomic. Therefore, we checked estrogenic regulation of C5a receptors and L-VGCC subunits. ER agonists increased C5aR mRNA expression, whereas they differentially regulated C5L2. Estradiol decreased transcription of Ca(v)1.3 L-VGCC subunit. Based on these results we propose that estradiol may differentially modulate C5a-induced Ca(2+)-influx via L-VGCCs in neurons depending on the expression of the two ER isotypes.


Assuntos
Canais de Cálcio Tipo L/fisiologia , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/metabolismo , Neurônios/metabolismo , Receptor da Anafilatoxina C5a/metabolismo , Animais , Cálcio/metabolismo , Canais de Cálcio/fisiologia , Sinalização do Cálcio/fisiologia , Linhagem Celular Transformada , Receptor alfa de Estrogênio/agonistas , Receptor beta de Estrogênio/agonistas , Camundongos , Neurônios/citologia , Neurônios/efeitos dos fármacos , Receptor da Anafilatoxina C5a/agonistas , Receptor da Anafilatoxina C5a/genética
10.
Biochim Biophys Acta ; 1819(5): 411-8, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22285573

RESUMO

Japanese encephalitis virus (JEV) NS5 consists of an N-terminal guanylyltransferase/methyltransferase (MTase) domain and a C-terminal RNA-dependent RNA polymerase (RdRp) domain. We purified JEV NS5 from bacteria and examined its RdRp activity in vitro. It showed exclusive specificity for Mn(2+) and alkaline conditions (pH 8-10) for RdRp activity. It showed strong RdRp activity with dinucleotide primers, and the order of template strength was poly(U)>(I)>(A)>(C). It showed weak transcription activity without primers, but could not transcribe poly(I) without primers. It bound homopolymeric RNA templates, but weakly bound poly(C). The Km (µM) values were 22.13±1.11 (ATP), 21.94±3.88 (CTP), 21.27±1.23 (GTP), and 9.91±0.30 (UTP), indicating low substrate affinity. Vmax (/min) values were 0.216±0.017 (ATP), 0.781±0.020 (CTP), 0.597±0.049 (GTP), and 0.347±0.022 (UTP), indicating high polymerization activity. The RdRp domain alone did not show RdRp activity; a structural and functional interaction between the MTase and RdRp domains via 299-EHPYRTWTYH-308 (MTase domain) and 739-LIGRARISPG-748 (RdRp domain) was predicted, because mutations in the MTase domain affected RdRp activity.


Assuntos
Vírus da Encefalite Japonesa (Espécie)/enzimologia , Metiltransferases , RNA Polimerase Dependente de RNA , Proteínas não Estruturais Virais , Concentração de Íons de Hidrogênio , Cinética , Metiltransferases/química , Metiltransferases/metabolismo , Estrutura Terciária de Proteína , RNA Polimerase Dependente de RNA/química , RNA Polimerase Dependente de RNA/metabolismo , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/metabolismo
11.
J Gastroenterol ; 47(4): 452-60, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22170414

RESUMO

BACKGROUND: The hedgehog (Hh) signaling pathway is aberrantly activated in many cancers. Overproduction of sonic hedgehog (Shh), a ligand in the Hh pathway, increases Hh signaling activity by inhibiting Patched-1 (Ptch1), a suppressive receptor in the Hh pathway. The purpose of this study was to establish a novel strategy for treating pancreatic cancer and other Hh-dependent cancers through control of the tumor-suppressive function of Ptch1. METHODS: We synthesized seven interacting peptides to the amino-acid sequence of the Ptch1 docking site for Shh. Human pancreatic cancer cell lines (AsPC-1, SUIT2) were cultured in the presence or absence of the peptides. Cell proliferation was assessed by cell counting and by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The activity of the Hh pathway was estimated by real-time polymerase chain reaction of the target gene product Gli1. To confirm their anti-tumor activity in vivo, the effect of the peptides in a mouse model of pancreatic cancer was determined. Finally, the Hh signaling activity of the xenograft was examined. RESULTS: Three of the interacting peptides to Ptch1 suppressed the proliferation of the two pancreatic cancer cell lines and decreased the expression of Gli1, both in vitro and in vivo. CONCLUSIONS: This study suggests that interacting peptides to Ptch1 may be a new tool for controlling the Hh-dependent growth of pancreatic cancer.


Assuntos
Proteínas Hedgehog/metabolismo , Neoplasias Pancreáticas/metabolismo , Peptídeos/farmacologia , Receptores de Superfície Celular/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Proliferação de Células , Modelos Animais de Doenças , Feminino , Humanos , Camundongos , Camundongos SCID , Neoplasias Pancreáticas/tratamento farmacológico , Receptores Patched , Receptor Patched-1 , Peptídeos/uso terapêutico , Reação em Cadeia da Polimerase em Tempo Real
12.
Anticancer Res ; 31(7): 2511-6, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21873168

RESUMO

We generated an evolutionary computer program that generates complementary peptide (C-pep) sequences, with the potential to interact with a target peptide, by comparing several physico-chemical parameters of each pair of the complementary peptides being analyzed. We generated C-peps to target several molecules. About 30% of synthesized C-peps interfered with the function of their targets. C5a stimulates generation of TNFα and other inflammatory cytokines. Inhibition of C5a should be effective against sepsis, which impairs the status of cancer-bearing patients. One of the inhibitory C-peps of C5a, termed AcPepA, was effective in Cynomolgus monkeys intravenously infused with a lethal dose of bacterial LPS (4 mg/kg) destined to die. The monkeys were rescued by intravenous administration of 2 mg/kg/h of AcPepA. The excellent therapeutic effect of AcPepA is likely to be due to restriction of high mobility group box 1 (HMGB1) surge induced by the effect of C5a on C5L2, which is the second C5a receptor, since the released HMGB1 has the capacity to stimulate TLR4 as an endogeneous ligand resulting in further activation of inflammatory cells to release inflammatory cytokines forming a positive feedback circuit of inflammation.


Assuntos
Terapia de Alvo Molecular , Biblioteca de Peptídeos , Peptídeos/uso terapêutico , Sequência de Aminoácidos , Animais , Complemento C5a/antagonistas & inibidores , Citocinas/metabolismo , Evolução Molecular Direcionada , Avaliação Pré-Clínica de Medicamentos , Endotoxemia/tratamento farmacológico , Endotoxemia/patologia , Endotoxemia/fisiopatologia , Retroalimentação Fisiológica , Proteína HMGB1/fisiologia , Inflamação/tratamento farmacológico , Inflamação/fisiopatologia , Lipopolissacarídeos/toxicidade , Pulmão/patologia , Macaca fascicularis , Dados de Sequência Molecular , Peptídeos/síntese química , Peptídeos/química , Peptídeos/farmacologia , Receptor da Anafilatoxina C5a/fisiologia , Software , Relação Estrutura-Atividade , Receptor 4 Toll-Like/fisiologia , Fator de Necrose Tumoral alfa/análise
13.
Intensive Care Med ; 36(12): 2132-9, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20845025

RESUMO

PURPOSE: To evaluate effects of endothelin receptor antagonist ETR-P1/fl in a neonatal sepsis model. METHOD: Eighteen anesthetized and mechanically ventilated 3-day-old piglets were divided into three groups. Six piglets received cecal ligation and perforation (CLP group). Six piglets were administrated a continuous infusion of ETR-P1/fl (0.05 mg/kg/h), an antisense homology box-derived peptide with an endothelin A receptor antagonist effect, starting 30 min after CLP (ETR-P1/fl group). Six piglets acted as the sham group. Mean arterial pressure (MAP), heart rate, cardiac output, arterial blood gas, body temp (BT), serum nitrite and nitrate (NOx), tumor necrosis factor (TNF)-α, and high-mobility group box 1 (HMGB-1) were measured before CLP and at 1, 3, 6, and 9 h after CLP. RESULTS: Cecal ligation and perforation exposure evoked a state of shock and showed deteriorated cardiac output, pulmonary hypertension, decreased MAP, low oxygen saturation, and base excess (BE) with elevated TNF-α, NOx, and HMGB1. ETR-P1/fl administration resulted in higher MAP at 6 and 9 h after CLP, less negative BE, lower mean pulmonary arterial pressure (mPAP)/MAP ratio at 9 h after CLP, and lower TNF-α, NOx, and HMGB-1 compared to the CLP group. BT showed no differences between the groups. Survival time in the ETR-P1/fl group was longer than in the CLP group (18.9 ± 2.3 h vs. 9.0 ± 0.8 h, p < 0.01). CONCLUSIONS: ETR-P1/fl treatment significantly attenuated the elevation of NOx, TNF-α, and HMGB-1, which improved the systemic hypotension, pulmonary hypertension, and blood gases, thereby causing improvement of survival time in a progressive neonatal sepsis CLP model.


Assuntos
Modelos Animais de Doenças , Antagonistas dos Receptores de Endotelina , Inflamação/prevenção & controle , Sepse/prevenção & controle , Animais , Animais Recém-Nascidos , Sepse/mortalidade , Taxa de Sobrevida , Suínos , Fatores de Tempo
14.
Biol Pharm Bull ; 33(7): 1256-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20606325

RESUMO

Carboxypeptidase R (CPR), also known as thrombin-activatable fibrinolysis inhibitor (TAFI), is an enzyme generated by proteolytic cleavage of its zymogen (proCPR). CPR removes the C-terminal arginine from inflammatory peptides such as C3a and C5a, bradykinin, enkephalin, and the thrombin-cleaved N-terminal fragment osteopontin (cleaved N-OPN). In the mouse model of concanavalin A (Con A)-induced immune-mediated fulminating hepatitis, cleaved N-OPN is one of the important peptides that induce the production of chemokines or cytokines. In the current study using proCPR deficient mice, we showed that injection of Con A into the mouse tail vein can induce a significantly higher lethality in proCPR-deficient female but not in male mice. Furthermore, a lack of CPR activity increased serum macrophage inflammatory protein-2 (MIP-2) and high-mobility group box 1 (HMGB1) levels after Con A injection. These in vivo findings suggest that CPR helps to protect against Con A-induced hepatitis.


Assuntos
Carboxipeptidase B2/deficiência , Doença Hepática Induzida por Substâncias e Drogas/patologia , Concanavalina A/toxicidade , Animais , Doença Hepática Induzida por Substâncias e Drogas/enzimologia , Quimiocinas/sangue , Citocinas/sangue , Ensaio de Imunoadsorção Enzimática , Feminino , Camundongos
15.
Transplantation ; 90(12): 1358-65, 2010 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-21197712

RESUMO

BACKGROUND: Complement 5a factor (C5a) elicits a broad range of proinflammatory effects, including chemotaxis of inflammatory cells and cytokine release. C5a is also linked to the coagulant activity in autoimmune diseases. Therefore, C5a most likely plays a crucial role in the instant blood-mediated inflammatory reaction. METHODS: Intraportal transplantation of 2.5 islet equivalents/g of syngeneic rat islet grafts was performed in two groups of streptozotocin-induced diabetic rats: controls and C5a inhibitory peptide (C5aIP)-treated group. RESULTS: The thrombin-antithrombin complex was significantly suppressed in the C5aIP group (P=0.003), and both the curative rate and the glucose tolerance were significantly improved in the C5aIP group (P<0.05 and P<0.005, respectively). Expression of tissue factor on granulocytes in recipient livers was up-regulated 1 h after islet infusion (P<0.0001), which was significantly suppressed by C5aIP (P<0.005). However, C5aIP was unable to regulate tissue factor expression on isolated islets. Furthermore, no differences were detected between the groups, regarding infiltration of CD11b-positive cells and deposition of C5b-9 on the islet grafts. CONCLUSIONS: These data suggest that C5aIP attenuates cross-talk between the complement and coagulation cascades through suppressing up-regulation of tissue factor expression on leukocytes in recipient livers but not on islet grafts, a process leading to improvement in islet engraftment. Therefore, C5aIP in combination with conventional anticoagulants could be a strong candidate strategy to control the instant blood-mediated inflammatory reaction induced in clinical islet transplantation.


Assuntos
Complemento C5a/antagonistas & inibidores , Transplante das Ilhotas Pancreáticas/métodos , Sistema Porta/fisiologia , Animais , Anticoagulantes/uso terapêutico , Antitrombinas/imunologia , Coagulação Sanguínea/fisiologia , Complemento C5a/fisiologia , Proteínas do Sistema Complemento/fisiologia , Diabetes Mellitus Experimental/cirurgia , Granulócitos/fisiologia , Inflamação/prevenção & controle , Transplante das Ilhotas Pancreáticas/fisiologia , Fígado/fisiologia , Ratos , Ratos Endogâmicos Lew , Trombina/imunologia , Tromboplastina/genética , Transplante Isogênico/fisiologia , Resultado do Tratamento , Regulação para Cima
16.
Cytotechnology ; 56(3): 209-17, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19002859

RESUMO

From unfractionated embryonic mice liver cells, appreciable amount of spherical bodies containing nestin-positive cells were generated in the presence of neuronal growth factors. Following cultivation on poly-D: -lysine/laminin-coated slips, approximately 70% of the cells expressed neuronal markers, and 16% had long processes. Functional analysis of these long-process-bearing cells with the whole-cell patch clamp method showed an inward current in response to glutamate, GABA, and serotonin as the neuronal characteristics. Furthermore, regenerating liver in adult mice also contained nestin-positive cells to the same extent as fetal liver. Regenerating liver could have potential as a source of neural cells for autologous transplantation.

17.
Neurochem Int ; 52(4-5): 846-56, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-17996333

RESUMO

In the present study we examined presence of the complement C5a receptor (C5aR) in hypothalamic neurosecretory neurons of the rodent brain and effect of estrogen on C5aR expression. Whole cell patch clamp measurements revealed that magnocellular neurons in the supraoptic and paraventricular nuclei of hypothalamic slices of the rats responded to the C5aR-agonist PL37-MAP peptide with calcium ion current pulses. Gonadotropin-releasing hormone (GnRH) producing neurons in slices of the preoptic area of the mice also reacted to the peptide treatment with inward calcium current. PL37-MAP was able to evoke the inward ion current of GnRH neurons in slices from ovariectomized animals. The amplitude of the inward pulses became higher in slices obtained from 17beta-estradiol (E2) substituted mice. Calcium imaging experiments demonstrated that PL37-MAP increased the intracellular calcium content in the culture of the GnRH-producing GT1-7 cell line in a concentration-dependent manner. Calcium imaging also showed that E2 pretreatment elevated the PL37-MAP evoked increase of the intracellular calcium content in the GT1-7 cells. The estrogen receptor blocker Faslodex in the medium prevented the E2-evoked increase of the PL37-MAP-triggered elevation of the intracellular calcium content in the GT1-7 cells demonstrating that the effect of E2 might be related to the presence of estrogen receptor. Real-time PCR experiments revealed that E2 increased the expression of C5aR mRNA in GT1-7 neurons, suggesting that an increased C5aR synthesis could be involved in the estrogenic modulation of calcium response. These data indicate that hypothalamic neuroendocrine neurons can integrate immune and neuroendocrine functions. Our results may serve a better understanding of the inflammatory and neurodegeneratory diseases of the hypothalamus and the related neuroendocrine and autonomic compensatory responses.


Assuntos
Cálcio/metabolismo , Estrogênios/farmacologia , Hormônios/metabolismo , Hipotálamo/metabolismo , Neurônios/metabolismo , Sistemas Neurossecretores/metabolismo , Receptor da Anafilatoxina C5a/agonistas , Receptor da Anafilatoxina C5a/biossíntese , Animais , Núcleo Basal de Meynert/citologia , Núcleo Basal de Meynert/efeitos dos fármacos , Núcleo Basal de Meynert/metabolismo , Linhagem Celular , Eletrofisiologia , Feminino , Hormônio Liberador de Gonadotropina/metabolismo , Hipotálamo/citologia , Hipotálamo/efeitos dos fármacos , Técnicas In Vitro , Masculino , Camundongos , Neurônios/efeitos dos fármacos , Sistemas Neurossecretores/citologia , Sistemas Neurossecretores/efeitos dos fármacos , Técnicas de Patch-Clamp , Fenótipo , RNA/biossíntese , RNA/genética , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa
18.
Microbiol Immunol ; 51(5): 507-17, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17579260

RESUMO

Thrombin-activatable fibrinolysis inhibitor (TAFI) is an anaphylatoxin-inactivating enzyme generated by proteolytic cleavage of its zymogen, and is the same enzyme as that first designated by our group as procarboxypeptidase R (proCPR). TAFI in plasma is presumed to influence vascular disease in its role as a fibrinolysis inhibitor. The activity of TAFI is strongly influenced by genetic polymorphism, especially at amino acids Thr/Ala-147 and Thr/Ile-325. In this study, we analyzed 202 healthy controls who were not on any medication, had no unusual medical history and whose blood data were normal. In a previous report, we established an enzyme-linked immunosorbent assay (ELISA) specific for non-activated TAFI (proCPR), and investigated levels of unactivated TAFI as an estimate of anti-fibrinolytic capacity. In this study, we determined normal Japanese TAFI levels for each age, sex, and genetic polymorphism of Thr/Ala-147 and Thr/Ile-325, and also showed that the TAFI level in young adult women is lower than in aged women.


Assuntos
Carboxipeptidase B2/sangue , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Carboxipeptidase B2/biossíntese , Carboxipeptidase B2/genética , Regulação para Baixo , Ativação Enzimática , Ensaio de Imunoadsorção Enzimática , Feminino , Variação Genética , Genótipo , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único , Valores de Referência , Fatores Sexuais
19.
Microbiol Immunol ; 51(4): 439-43, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17446684

RESUMO

Amino acids 37 to 53 (RAARISLGPRCIKAFTE) of C5a anaphylatoxin form an essential region for C5a function. To target this sequence, we generated a complementary peptide (ASGAPAPGPAGPLRPMF) designated PepA which has a potent inhibitory effect on C5a activity. By introducing an acetyl group at the N-terminal alanine of PepA, an acetylated form was generated which was designated AcPepA. The acetylation resulted in increased inhibition of C5a stimulation of neutrophils as determined by Ca influx. Furthermore, AcPepA partially inhibited the lethal shock induced in mice by intravenous administration of Candida albicans water-soluble mannoprotein-beta-glucan complex. In addition, local skin inflammation in rats caused by an anti-Crry monoclonal antibody was suppressed when AcPepA and the antibody were injected together, while PepA had little inhibitory capacity. The potent inhibitory capacity of AcPepA was also confirmed by a skin reaction of guinea pigs inoculated with recombinant human C5a together with AcPepA.


Assuntos
Alanina/química , Complemento C5a/antagonistas & inibidores , Fragmentos de Peptídeos/farmacologia , Acetilação , Animais , Complemento C5a/metabolismo , Cobaias , Inflamação/imunologia , Fragmentos de Peptídeos/química , Pele/efeitos dos fármacos
20.
Exp Mol Pathol ; 82(2): 220-6, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17208225

RESUMO

We have established a mouse model which shows the symptoms of coronary arteritis after consecutive injections of CAWS, which is released from Candida albicans. In this study, we examined neutrophil activation in the initial period after CAWS injection intraperitoneally. During 10 min to 16 h after the injection, blood profiles and neutrophil functions were determined. At the same time, levels of inflammatory cytokines and chemokines in plasma were measured. Furthermore, level of ICAM-1 as a marker of lesion in arterial endothelial cells was measured. Counts of the peripheral leukocytes increased immediately after CAWS injection, especially involving neutrophil. In vitro sensitivity of neutrophils to stimuli was enhanced. Moreover, proinflammatory cytokines (IL-1beta, IL-12 and IL-6) increased in plasma initially followed by an increase in IL-10, G-CSF, MIP-2 and soluble ICAM-1. Locally, ICAM-1 message in arterial walls was significantly increased 16 h after CAWS injection. A decrease in C3 levels was observed in plasma, suggesting complement activation and consumption. In summary, neutrophil activation occurred after CAWS injection, followed by complement activation, and production of proinflammatory cytokines chemokines and G-CSF which may be involved in development of coronary arteritis.


Assuntos
Arterite/imunologia , Candida albicans/patogenicidade , Glicoproteínas de Membrana , Ativação de Neutrófilo , beta-Glucanas , Animais , Arterite/induzido quimicamente , Arterite/patologia , Candida albicans/química , Complemento C3/metabolismo , Vasos Coronários/metabolismo , Vasos Coronários/patologia , Citocinas/sangue , Modelos Animais de Doenças , Fator Estimulador de Colônias de Granulócitos/sangue , Molécula 1 de Adesão Intercelular/metabolismo , Masculino , Glicoproteínas de Membrana/química , Camundongos , Solubilidade , Água , beta-Glucanas/química
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