RESUMO
Immunogenic cell death (ICD) is a form of regulated cell death (RCD) induced by various stresses and produces antitumor immunity via damage-associated molecular patterns (DAMPs) release or exposure, mainly including high mobility group box 1 (HMGB1), calreticulin (CRT), adenosine triphosphate (ATP), and heat shock proteins (HSPs). Emerging evidence has suggested that ionizing radiation (IR) can induce ICD, and the dose, type, and fractionation of irradiation influence the induction of ICD. At present, IR-induced ICD is mainly verified in vitro in mice and there is few clinical evidence about it. To boost the induction of ICD by IR, some strategies have shown synergy with IR to enhance antitumor immune response, such as hyperthermia, nanoparticles, and chemotherapy. In this review, we focus on the molecular mechanisms of ICD, ICD-promoting factors associated with irradiation, the clinical evidence of ICD, and immunogenic forms of cell death. Finally, we summarize various methods of improving ICD induced by IR.
Assuntos
Morte Celular Imunogênica/efeitos da radiação , Alarminas/fisiologia , Animais , Antígenos de Neoplasias/imunologia , Biomarcadores , Terapia Combinada , Citocinas/fisiologia , Relação Dose-Resposta à Radiação , Ferroptose/efeitos da radiação , Proteína HMGB1/fisiologia , Humanos , Hipertermia Induzida , Camundongos , Morfolinas/uso terapêutico , Necroptose/efeitos da radiação , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Neoplasias/radioterapia , Piperazinas/uso terapêutico , Pirróis/uso terapêutico , Tolerância a Radiação , Radiação IonizanteRESUMO
Sulforaphane (SFN), a natural isothiocyanate present in cruciferous vegetables such as broccoli and cabbage, is effective in preventing carcinogenesis, diabetes, and inflammatory responses. Inhibition of high mobility group box 1 (HMGB1) and restoration of endothelial integrity is emerging as an attractive therapeutic strategy in the management of severe sepsis or septic shock. In this study, we examined the effects of SFN on HMGB1-mediated septic responses and survival rate in a mouse sepsis model. The anti-inflammatory activities of SFN were monitored based on its effects on lipopolysaccharide (LPS)- or cecal ligation and puncture (CLP)-mediated release of HMGB1. The antiseptic activities of SFN were determined by measuring permeability, leukocyte adhesion and migration, and the activation of pro-inflammatory proteins in HMGB1-activated human umbilical vein endothelial cells (HUVECs) and mice. SFN inhibited the release of HMGB1 and downregulated HMGB1-dependent inflammatory responses in human endothelial cells. SFN also inhibited HMGB1-mediated hyperpermeability and leukocyte migration in mice. In addition, treatment with SFN reduced CLP-induced release of HMGB1 and sepsis-related mortality and pulmonary injury in vivo. Our results indicate that SFN is a possible therapeutic agent that can be used to treat various severe vascular inflammatory diseases via the inhibition of the HMGB1 signaling pathway.
Assuntos
Anti-Inflamatórios , Proteína HMGB1/antagonistas & inibidores , Proteína HMGB1/fisiologia , Mediadores da Inflamação/metabolismo , Mediadores da Inflamação/fisiologia , Isotiocianatos/farmacologia , Isotiocianatos/uso terapêutico , Fitoterapia , Sepse/tratamento farmacológico , Sepse/genética , Transdução de Sinais/efeitos dos fármacos , Animais , Brassicaceae/química , Movimento Celular/efeitos dos fármacos , Modelos Animais de Doenças , Proteína HMGB1/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Leucócitos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , SulfóxidosRESUMO
Hypaconitine is an active component of Aconitum carmichaelii Debx, a Chinese medicinal herb for the treatment of cardiovascular diseases, but the mechanism underlying its effect remains elusive. In this study, we found that hypaconitine, rather than aconitum alkaloids in A. carmichaelii (e.g. aconitine, mesaconitine and benzoylaconitine), prevented endothelial cells from damage due to oxidized low-density lipoprotein (oxLDL) challenge. Cleaved caspase 3 expression in endothelial cells was up-regulated by oxLDL and markedly attenuated by hypaconitine, suggesting that hypaconitine inhibited the oxLDL-induced cell apoptosis. Microarray analysis revealed that histone deacetylase 3 (HDAC3) was significantly increased by hypaconitine. The cytoplasmic relocation and extracellular release of high-mobility group box 1 (HMGB1, an HDAC3 downstream effector) in endothelial cells were significantly increased by oxLDL and markedly decreased by hypaconitine. The effect of hypaconitine on the oxLDL-induced apoptosis and HMGB1 release in endothelial cells was significantly reduced by the suppression of HDAC3 by siRNA or a specific inhibitor. Thus, this study proves that the histone deacetylase-HMGB1 pathway targeted by hypaconitine suppresses the apoptosis of endothelial cells. Our findings are of therapeutic significance and provide the potential of hypaconitine exploitation. Impact statement First, our study shows the antiapoptosis effect of Aconitum carmichaelii and its active component hypaconitine on endothelial cells. It may provide new strategies for the treatment of diseases involving endothelium damage. Second, this finding indicates the function of hypaconitine in regulating HDAC3-HMGB1 pathway, which suggests a new anti-inflammatory therapy. Third, due to its poisonousness, A. carmichaelii is always used with caution in clinics. Thus, the identification of hypaconitine as an active component of A. carmichaelii could contribute to the development of toxicity-decreasing procedure for A. carmichaelii.
Assuntos
Aconitina/análogos & derivados , Apoptose/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Proteína HMGB1/efeitos dos fármacos , Histona Desacetilases/efeitos dos fármacos , Aconitina/farmacologia , Aconitum/química , Apoptose/fisiologia , Western Blotting , Linhagem Celular , Células Endoteliais/fisiologia , Ensaio de Imunoadsorção Enzimática , Proteína HMGB1/fisiologia , Histona Desacetilases/fisiologia , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologiaRESUMO
The nucleosomal protein high-mobility group box-1 (HMGB1), which has recently been established as a late mediator of lethal systemic inflammation, has a relatively wide therapeutic window for pharmacological interventions. Compounds produced by marine-derived microbes have been widely investigated for their potential use as bioactive natural products. Cyclic dipeptides, which are also known as diketopiperazines, are molecules that are frequently found in marine-derived microorganisms. While their pharmacological potential has been well established, their biological activities against septic responses have not yet been reported. Here, three diketopiperazines (1-3) isolated from two strains of marine-derived bacteria were investigated for their potential activities against HMGB1-mediated septic responses. The data showed that 1-3 effectively inhibited the lipopolysaccharide (LPS)-induced release of HMGB1 and suppressed the HMGB1-mediated septic responses, including hyperpermeability, leukocyte adhesion and migration, and cell adhesion molecule expression. In addition, 1-3 inhibited the HMGB1-mediated production of tumor necrosis factor-[Formula: see text] (TNF-[Formula: see text] and interleukin (IL)-6 and the activation of nuclear factor-[Formula: see text]B (NF-[Formula: see text]B) and extracellular signal-regulated kinase (ERK) 1 and ERK2. Collectively, these results indicated that 1-3 might act as potential therapeutic agents for various severe vascular inflammatory diseases through the inhibition of the HMGB1 signaling pathway.
Assuntos
Actinomycetales/química , Anti-Infecciosos Locais/farmacologia , Bacillus/química , Dicetopiperazinas/farmacologia , Proteína HMGB1/efeitos adversos , Poríferos/microbiologia , Sepse/tratamento farmacológico , Actinomycetales/isolamento & purificação , Animais , Anti-Infecciosos Locais/química , Anti-Infecciosos Locais/isolamento & purificação , Anti-Infecciosos Locais/uso terapêutico , Bacillus/isolamento & purificação , Sobrevivência Celular/efeitos dos fármacos , Dicetopiperazinas/química , Dicetopiperazinas/isolamento & purificação , Dicetopiperazinas/uso terapêutico , Modelos Animais de Doenças , Sedimentos Geológicos/microbiologia , Proteína HMGB1/fisiologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Camundongos Endogâmicos C57BL , Sepse/genética , Choque Séptico/tratamento farmacológico , Choque Séptico/genéticaRESUMO
Salicornia herbacea is an annual halophytic glasswort that has been employed as a culinary vegetable, salad, and traditional medicinal resource. Chemical investigation of the aerial parts of S. herbacea led to the isolation of two new (1, 2) and known (3) flavanones as well as a new nature-derived (4) and two known chromone derivatives (5, 6). These purified compounds were evaluated for their suppressive potentials against the release of high-mobility group box 1 protein (HMGB1), which has captured attention as a viable target for alleviating serious septic manifestations or septicemia. The phenolic compounds improved the survival rates of cecal ligation and puncture operation (CLP) in murine models, simulating severe septic shock and its related complications, to 40-60%. These results collectively validate that flavanone- and chromone-based secondary metabolites may serve as prospective prodrugs or food additives that may be commercialized for the control of septic complications and lethality.
Assuntos
Chenopodiaceae/química , Cromonas/uso terapêutico , Endotélio Vascular/efeitos dos fármacos , Flavanonas/uso terapêutico , Componentes Aéreos da Planta/química , Sepse/tratamento farmacológico , Animais , Ceco/cirurgia , Cromonas/isolamento & purificação , Modelos Animais de Doenças , Flavanonas/isolamento & purificação , Proteína HMGB1/antagonistas & inibidores , Proteína HMGB1/fisiologia , Células Endoteliais da Veia Umbilical Humana , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fitoterapia , Choque Séptico/tratamento farmacológicoRESUMO
Excessive release of high mobility group box-1 (HMGB1) protein from ischemic cardiomyocytes activates inflammatory cascades and enhances myocardial injury after reperfusion. Here we report evidence that electroacupuncture of mice at Neiguan acupoints can inhibit the up-regulation of cardiac HMGB1 following myocardial ischemia and attenuate the associated inflammatory responses and myocardial injury during reperfusion. These benefits of electroacupuncture were partially reversed by administering recombinant HMGB1 to the mice, and further potentiated by administering anti-HMGB1 antibody. Electroacupuncture-induced inhibition of HMGB1 release was markedly reduced by unilateral vagotomy or administration of nicotinic receptor antagonist, but not by chemical sympathectomy. The cholinesterase inhibitor neostigmine mimicked the effects of electroacupuncture on HMGB1 release and myocardial ischemia reperfusion injury. Culture experiments with isolated neonatal cardiomyocytes showed that acetylcholine, but not noradrenaline, inhibited hypoxia-induced release of HMGB1 via a α7nAchR-dependent pathway. These results suggest that electroacupuncture acts via the vagal nerve and its nicotinic receptor-mediated signaling to inhibit HMGB1 release from ischemic cardiomyocytes. This helps attenuate pro-inflammatory responses and myocardial injury during reperfusion.
Assuntos
Eletroacupuntura , Proteína HMGB1/fisiologia , Isquemia Miocárdica/prevenção & controle , Traumatismo por Reperfusão/prevenção & controle , Animais , CamundongosRESUMO
The ubiquitous nuclear protein, high mobility group box 1 (HMGB1), is released by activated macrophages and human umbilical vein endothelial cells (HUVECs) and functions as a late mediator of experimental sepsis. Aspalathin (Asp) and nothofagin (Not), which have been reported to have anti-oxidant activity, are the two major active dihydrochalcones found in green rooibos. In this study, we investigated the antiseptic effects and underlying mechanisms of Asp and Not against HMGB1-mediated septic responses in HUVECs and mice. The anti-inflammatory activities of Asp and Not were determined by measuring permeability, monocyte adhesion and migration, and activation of proinflammatory proteins in HMGB1-activated HUVECs and mice. According to the results, Asp and Not effectively inhibited lipopolysaccharide (LPS)-induced release of HMGB1, and suppressed HMGB1-mediated septic responses, such as hyperpermeability, adhesion and migration of leukocytes, and expression of cell adhesion molecules. In addition, Asp and Not suppressed the production of tumor necrosis factor alpha (TNF-α) and interleukin 6 (IL-6), the activation of nuclear factor-κB (NF-κB) and extracellular signal-regulated kinases 1 and 2 (ERK1/2) by HMGB1. Collectively, these results indicate that Asp and Not could be potential therapeutic agents for the treatment of various severe vascular inflammatory diseases via the inhibition of the HMGB1 signaling pathway.
Assuntos
Anti-Inflamatórios , Aspalathus/química , Chalconas/farmacologia , Chalconas/uso terapêutico , Proteína HMGB1/efeitos adversos , Proteína HMGB1/fisiologia , Fitoterapia , Sepse/tratamento farmacológico , Sepse/genética , Animais , Antioxidantes , Chalconas/isolamento & purificação , Modelos Animais de Doenças , Células Endoteliais da Veia Umbilical Humana , Humanos , Interleucina-6/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismoRESUMO
OBJECTIVE: To study the effects of 1,25-(OH)(2)D(3) on airway remodeling and expression of high mobility group box 1 (HMGB1) and IL-17 in asthmatic mice. METHODS: Fifty female mice were randomly divided into 5 groups: control, asthma, low-dose, middle-dose, and high-dose intervention groups (n=10 each). Asthma was induced by intraperitoneal injections of ovalbumin (OVA) and aerosol inhalation of OVA solution. The low-dose, middle-dose, and high-dose intervention groups were administered with 1,25-(OH)(2)D(3) solution at the dosage of 1, 4 and 10 µg/kg respectively by intraperitoneal injections before asthma challenge. The airway structural changes were assessed by hematoxylin and eosin staining. mRNA expression levels of HMGB1 and IL-17 in the lung tissues were evaluated by RT-PCR. The protein levels of HMGB1 and IL-17 in the lung tissues were observed by immunohistochemistry. RESULTS: The airway wall thickness, protein and mRNA expression levels of HMGB1 and IL-17 were higher in the untreated asthma group than in the control group (P<0.05). The airway wall thickness, protein and mRNA expression levels of HMGB1 and IL-17 were lower in the middle-dose and low-dose intervention groups than in the untreated asthma group, and the middle-dose intervention group demonstrated lower airway wall thickness, protein and mRNA expression levels of HMGB1 and IL-17 than in the low-dose intervention group (P<0.05). However, the airway wall thickness, protein and mRNA expression levels of HMGB1 and IL-17 in the high-dose intervention group were higher than in the untreated asthma group (P<0.05). CONCLUSIONS: HMGB1 and IL-17 may be involved in the airway remodeling process in asthmatic mice. A moderate amount of HMGB1 and IL-17 may be involved in the airway remodeling process in asthmatic mice. A moderate amount of 1,25-(OH)(2)D(3) can improve the airway remodeling, but a higher dose of 1,25-(OH)(2)D(3) may affect adversely the airway remodeling process.
Assuntos
Asma/tratamento farmacológico , Calcitriol/farmacologia , Proteína HMGB1/fisiologia , Interleucina-17/fisiologia , Remodelação das Vias Aéreas/efeitos dos fármacos , Animais , Asma/metabolismo , Asma/patologia , Relação Dose-Resposta a Droga , Feminino , Proteína HMGB1/análise , Proteína HMGB1/genética , Interleucina-17/análise , Interleucina-17/genética , Pulmão/metabolismo , Pulmão/patologia , Camundongos , Camundongos Endogâmicos BALB CRESUMO
Signals released by leukocytes contribute to tumor growth and influence the efficacy of antineoplastic treatments. The outcome of peritoneal carcinomatosis treatments is unsatisfactory, possibly because chemotherapy activates events that have in the long-term deleterious effects. In this study we offer evidence that 5-fluorouracile (5-FU), besides provoking apoptosis of MC38 colon carcinoma cells, induces a striking attraction of leukocytes both in an orthotopic model of colon carcinomatosis in vivo and in monocyte-migration assays in vitro. Leukocyte attraction depends on the presence of High Mobility Group Box 1 (HMGB1), an endogenous immune adjuvant and chemoattractant released by dying cells. Leukocyte recruitment is prevented in vivo and in vitro using blocking antibodies against HMGB1 and its competitive antagonist BoxA or by interfering with HMGB1 expression. Autophagy is required for leukocyte chemoattraction, since the latter abates upon pharmacological blockade of the autophagic flux while activation of autophagy per se, in the absence of death of colon carcinoma cells, is not sufficient to attract leukocytes. Our results identify autophagy induction and HMGB1 release in colon carcinoma cells as key events responsible for 5-FU elicited leukocyte attraction and define a novel rate-limiting target for combinatorial therapies.
Assuntos
Antimetabólitos Antineoplásicos/farmacologia , Autofagia/efeitos dos fármacos , Neoplasias do Colo/tratamento farmacológico , Fluoruracila/farmacologia , Proteína HMGB1/fisiologia , Leucócitos/efeitos dos fármacos , Cavidade Peritoneal/citologia , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Neoplasias do Colo/patologia , Feminino , Humanos , Leucócitos/fisiologia , Camundongos , Camundongos Endogâmicos C57BLRESUMO
Extracellular high mobility group box 1 (HMGB1) protein and nitric oxide (NO) has been credited with multiple inflammatory functions using in vivo and in vitro systems. Therefore, delineating their regulation may be an important therapeutic strategy for the treatment of sepsis. In the present study, it is demonstrated that recombinant HMGB1 (rHMGB1) synergizes with sub threshold concentration of TLR2 agonist (PGN; 1 µg/ml) as well as with TLR4 agonist (LPS; 1 ng/ml) to induce NO release in mouse peritoneal macrophages. The enhanced iNOS expression was also observed at the transcription and translational level. Co-incubation of macrophages with rHMGB1 with either PGN or LPS showed enhanced expression of TLR2, TLR4 and RAGE. TLR2, TLR4 or RAGE knockdown macrophages effectively inhibited the rHMGB1+PGN or LPS induced NO synergy. It was further observed that the JNK MAPK inhibitor SP600125 attenuated the PGN+rHMGB1 induced iNOS/NO synergy whereas p38 MAPK inhibitor SB908912 inhibited iNOS/NO synergy induced by LPS+rHMGB1. It was also observed that the activation of NF-κB is essential for the synergy as the pharmacological inhibition or siRNA knockdown of NF-κB (cRel) significantly reduced the rHMGB1+PGN or rHMGB1+LPS induced enhanced iNOS/NO expression. Altogether, the data suggests that the co-incubation of macrophages with rHMGB1 with either LPS or PGN induces the synergistic effect on iNOS expression and NO release by the upregulation of surface receptors (TLR2, TLR4 and RAGE) which in turn amplifies the MAPKs (p38 and JNK) and NF-κB activation and results in enhanced iNOS expression and NO production.
Assuntos
Proteína HMGB1/farmacologia , Lipopolissacarídeos/farmacologia , Macrófagos Peritoneais/efeitos dos fármacos , Óxido Nítrico/metabolismo , Peptidoglicano/farmacologia , Animais , Anti-Inflamatórios/farmacologia , Células Cultivadas , Avaliação Pré-Clínica de Medicamentos , Sinergismo Farmacológico , Feminino , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Ácido Glicirrízico/farmacologia , Proteína HMGB1/administração & dosagem , Proteína HMGB1/fisiologia , Lipopolissacarídeos/administração & dosagem , Macrófagos Peritoneais/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Peptidoglicano/administração & dosagemRESUMO
As a late mediator of inflammation, high mobility group box 1 (HMGB1) protein up-regulates pro-inflammatory cytokines in several inflammatory diseases. Further, high plasma levels of HMGB1 correlate with poor prognosis and increased mortality in patients with severe inflammation. Oleanolic acid (OA), a triterpenoid known for its anti-inflammatory and anti-cancer properties, is commonly present in several medicinal plants but the effects of OA on HMGB1-mediated pro-inflammatory responses of human endothelial cells is not well-studied. In this study, we investigated this question by monitoring the effect of OA on lipopolysaccharide (LPS)-mediated release of HMGB1 and the HMGB1-mediated modulation of inflammatory responses in human umbilical vein endothelial cells (HUVECs). OA potently inhibited the release of HMGB1 by HUVECs as well as down-regulated HMGB1-dependent adhesion and migration of the monocytic cell line THP-1 to activated HUVECs. OA also down-regulated the cell surface expression of the receptor of HMGB1, thereby inhibiting HMGB1-dependent pro-inflammatory responses by inhibiting activation of nuclear factor-κB (NF-κB) and production of tumor necrosis factor-α (TNF-α) by HMGB1. Given these results, OA showed anti-inflammatory activities and could be a candidate as a therapeutic agent for various inflammatory diseases through the inhibition of the HMGB1 signaling pathway.
Assuntos
Anti-Inflamatórios/farmacologia , Endotélio Vascular/efeitos dos fármacos , Proteína HMGB1/fisiologia , Ácido Oleanólico/farmacologia , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Ensaio de Imunoadsorção Enzimática , Proteína HMGB1/metabolismo , Humanos , Espectroscopia de Ressonância Magnética , NF-kappa B/metabolismo , Fator de Necrose Tumoral alfa/biossíntese , Fator de Necrose Tumoral alfa/metabolismoRESUMO
After tissue damage, inflammatory cells infiltrate the tissue and release proinflammatory cytokines. HMGB1 (high mobility group box 1), a nuclear protein released by necrotic and severely stressed cells, promotes cytokine release via its interaction with the TLR4 (Toll-like receptor 4) receptor and cell migration via an unknown mechanism. We show that HMGB1-induced recruitment of inflammatory cells depends on CXCL12. HMGB1 and CXCL12 form a heterocomplex, which we characterized by nuclear magnetic resonance and surface plasmon resonance, that acts exclusively through CXCR4 and not through other HMGB1 receptors. Fluorescence resonance energy transfer data show that the HMGB1-CXCL12 heterocomplex promotes different conformational rearrangements of CXCR4 from that of CXCL12 alone. Mononuclear cell recruitment in vivo into air pouches and injured muscles depends on the heterocomplex and is inhibited by AMD3100 and glycyrrhizin. Thus, inflammatory cell recruitment and activation both depend on HMGB1 via different mechanisms.
Assuntos
Quimiocina CXCL12/fisiologia , Proteína HMGB1/fisiologia , Inflamação/etiologia , Receptores CXCR4/fisiologia , Animais , Sequência de Bases , Sinalização do Cálcio , Movimento Celular/fisiologia , Quimiocina CXCL12/química , DNA Complementar/genética , Fibroblastos/fisiologia , Transferência Ressonante de Energia de Fluorescência , Células HEK293 , Proteína HMGB1/química , Humanos , Inflamação/patologia , Inflamação/fisiopatologia , Sistema de Sinalização das MAP Quinases , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Modelos Moleculares , Monócitos/fisiologia , Complexos Multiproteicos/química , Células NIH 3T3 , Ressonância Magnética Nuclear Biomolecular , Receptor para Produtos Finais de Glicação Avançada , Receptores CXCR4/química , Receptores CXCR4/genética , Receptores Imunológicos/fisiologia , Transdução de Sinais , Ressonância de Plasmônio de Superfície , Receptores Toll-Like/fisiologia , TransfecçãoRESUMO
Most anticancer agents are thought to act through direct induction of tumoral, stromal and endothelial cell death by apoptosis or necrosis. In a 2008 issue of Bulletin de l'Académie Nationale de Médecine, we described an alternative (or complementary) theory whereby the immune system participates in the antitumoral effects of some chemotherapy or radiotherapy regimens by promoting an immunogenic cell death pathway. In particular, we showed the critical importance of two pre-mortem stressors that determine the immunogenicity of dying tumor cells. The first, an ER stress response culminating in calreticuline exposure at the tumor cell surface, is mandatory for the uptake and efficient phagocytosis of apoptotic bodies by dendritic cells. In the second, autophagy leads to the release of ATP by dying tumor cells, resulting in the recruitment of inflammatory phagocytes and antigen-presenting cells, and also triggering the inflammasome that causes IL-1beta release and CD8+ T cell polarization. The tumor microenvironment changes following chemotherapy, favoring sequential accumulation of a series of innate and cognate effectors that act in a coordinated fashion to promote tumor eradication. These findings will help to identify immune predictors of the response to conventional anticancer treatments and to design innovative combinatorial immunochemotherapy regimens.
Assuntos
Apresentação de Antígeno/efeitos dos fármacos , Antineoplásicos/farmacologia , Autofagia/efeitos dos fármacos , Ativação Linfocitária/efeitos dos fármacos , Modelos Imunológicos , Neoplasias/imunologia , Trifosfato de Adenosina/metabolismo , Animais , Antígenos de Neoplasias/imunologia , Antineoplásicos/uso terapêutico , Apoptose/imunologia , Autofagia/imunologia , Calreticulina/metabolismo , Citocinas/imunologia , Células Dendríticas/imunologia , Estresse do Retículo Endoplasmático , Proteína HMGB1/fisiologia , Humanos , Inflamassomos/imunologia , Interleucina-1beta/metabolismo , Camundongos , Neoplasias/tratamento farmacológico , Transporte Proteico , Subpopulações de Linfócitos T/efeitos dos fármacos , Subpopulações de Linfócitos T/imunologia , Receptor 4 Toll-Like/imunologiaRESUMO
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/análiseRESUMO
Thrombin activates immunocompetent microglia and increases release of inflammatory cytokines under intracerebral hemorrhage (ICH) insults. Also, thrombin injection into the striatum evokes acute necrosis and delayed apoptosis of neurons. A nucleoprotein high-mobility group box 1 (HMGB1) that is released from necrotic cells has been suggested to behave like a cytokine and cause over-facilitation of immune functions. Here we examined the effect of glycyrrhizin, known as an inhibitor of HMGB1, on thrombin-induced injury in rat cortico-striatal slice cultures and in vivo rat ICH model. In slice cultures, thrombin-induced a drastic increase in propidium iodide fluorescence indicating necrotic cell death in the cortical region, and robust shrinkage of the striatal tissue. Glycyrrhizin (10-100 µM) attenuated thrombin-induced cortical injury in a concentration-dependent manner. The protective effect of glycyrrhizin was not mediated by glucocorticoid receptors or modulation of nitric oxide production, but was reversed by exogenous HMGB1 application. The injury induced by a high concentration of HMGB1 was suppressed by glycyrrhizin. In vivo, unilateral injection of type IV collagenase into rat striatum induced ICH associated with brain edema formation, contralateral paralysis and neuron death. Once daily intraperitoneal administration of glycyrrhizin attenuated ICH-induced edema in both the cortex and the basal ganglia, and improved behavioral performance of rats in forelimb placing. Moreover, glycyrrhizin partially but significantly ameliorated ICH-induced neuron loss inside hematoma. These findings suggest that an HMGB1 inhibitor glycyrrhizin is a potential candidate for a remedy for ICH.
Assuntos
Anti-Inflamatórios/farmacologia , Hemorragia Cerebral/tratamento farmacológico , Hemorragia Cerebral/patologia , Ácido Glicirrízico/farmacologia , Proteína HMGB1/antagonistas & inibidores , Animais , Anti-Inflamatórios/metabolismo , Anti-Inflamatórios/uso terapêutico , Comportamento Animal/efeitos dos fármacos , Comportamento Animal/fisiologia , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Edema Encefálico/induzido quimicamente , Edema Encefálico/tratamento farmacológico , Edema Encefálico/metabolismo , Edema Encefálico/patologia , Lesões Encefálicas/induzido quimicamente , Lesões Encefálicas/complicações , Lesões Encefálicas/patologia , Bovinos , Morte Celular/efeitos dos fármacos , Morte Celular/fisiologia , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Hemorragia Cerebral/induzido quimicamente , Colagenases/fisiologia , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Corpo Estriado/patologia , Avaliação Pré-Clínica de Medicamentos , Ácido Glicirrízico/metabolismo , Ácido Glicirrízico/uso terapêutico , Proteína HMGB1/fisiologia , Hemostáticos/farmacologia , Masculino , Terapia de Alvo Molecular , Neostriado/efeitos dos fármacos , Neostriado/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Óxido Nítrico/análise , Óxido Nítrico/biossíntese , Ratos , Ratos Sprague-Dawley , Ratos Wistar , Trombina/farmacologia , Técnicas de Cultura de TecidosRESUMO
OBJECTIVE: High mobility group box-1 (HMGB1) is a nuclear chromatin protein. Furthermore, it induces chemotaxis and inflammation once released in the extracellular milieu, and it has been reported to upregulate, but also to inhibit HIV-1 replication in different cell types. We here investigated the potential role of extracellular HMGB1 in both R5 and X4 HIV-1 replication in primary human monocyte-derived macrophages (MDM) and U937 promonocytic cells, respectively. DESIGN: MDM or U937 cells were infected with R5 and X4 HIV-1 strains, respectively, in the presence or absence of endotoxin-free recombinant (r) HMGB1 or necrotic cell supernatants either containing or depleted of endogenous HMGB1. METHODS: HIV replication was measured by means of virion-associated reverse transcriptase activity in culture supernatants and cell-associated viral protein expression. Cytokine and chemokine production were measured by enzyme-linked immunosorbent assay; cell surface expression of CD4, CC chemokine receptor 5, receptor for advanced glycation end-products, Toll-like receptor-2 and Toll-like receptor-4 were analyzed by flow cytometry. RESULTS: Both rHMGB1 and necrotic cell supernatant-associated HMGB1 inhibited replication of R5 HIV-1 in MDM. Surprisingly enough, no upregulation of CC chemokine receptor 5-binding chemokines or of other chemokines and cytokines was observed in rHMGB1-stimulated MDM. HMGB1 also induced chemotaxis and strongly inhibited the replication of X4 HIV-1 in the 'Minus' subset of U937 cell clones expressing high levels of putative HMGB1 receptors (receptor for advanced glycation end-products, Toll-like receptors 2 and 4). CONCLUSION: Extracellular HMGB1 is a potent inhibitor of both R5 and X4 HIV-1 replication in mononuclear phagocytic cells without inducing the release of HIV-Modulatory chemokines or cytokines.