RESUMO
Di-d-psicose anhydride (DPA), derived from functional rare saccharide as d-psicose, is investigated for its strong chelating ability. Methylglyoxal (MGO), an important precursor of advanced glycation end-products (AGEs), promotes obesity, and causes complications such as diabetic nephropathy. On mesangial cells, DPA can substantially reduce the negative effects of MGO. DPA effectively trapping MGO in mesangial cells. The bonding properties of the DPA-MGO adduct were discussed by mass spectrometry and nuclear magnetic resonance (NMR). The NMR spectra of the DPA-MGO adduct provide evidence for chelation bonding. The inhibition of AGE formation and the mass spectrometry results of the DPA-MGO adduct indicate that DPA can scavenge MGO at a molar ratio of 1:1. DPA suppressed 330 % of the up-regulated receptor for an AGEs protein expression to a normal level and restored the suppressed glyoxalase 1 level to 86 % of the normal group. This research provides important evidence and theoretical basis for the development of AGE inhibitors derived from rare saccharide.
Assuntos
Nefropatias Diabéticas , Produtos Finais de Glicação Avançada , Aldeído Pirúvico , Aldeído Pirúvico/química , Nefropatias Diabéticas/tratamento farmacológico , Nefropatias Diabéticas/metabolismo , Nefropatias Diabéticas/prevenção & controle , Produtos Finais de Glicação Avançada/metabolismo , Produtos Finais de Glicação Avançada/antagonistas & inibidores , Células Mesangiais/efeitos dos fármacos , Células Mesangiais/metabolismo , Lactoilglutationa Liase/antagonistas & inibidores , Lactoilglutationa Liase/metabolismo , Humanos , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Receptor para Produtos Finais de Glicação Avançada/antagonistas & inibidores , Anidridos/química , Quelantes/química , Quelantes/farmacologiaRESUMO
BACKGROUND: Acute respiratory distress syndrome (ARDS) is characterized by alveolar edema that can progress to septal fibrosis. Mechanical ventilation can augment lung injury, termed ventilator-induced lung injury (VILI). Connective tissue growth factor (CTGF), a mediator of fibrosis, is increased in ARDS patients. Blocking CTGF inhibits fibrosis and possibly vascular leakage. This study investigated whether neutralizing CTGF reduces pulmonary edema in VILI. METHODS: Following LPS administration, rats were mechanically ventilated for 6 h with low (6 mL/kg; low VT) or moderate (10 mL/kg; mod VT) tidal volume and treated with a neutralizing CTGF antibody (FG-3154) or placebo lgG (vehicle). Control rats without LPS were ventilated for 6 h with low VT. Lung wet-to-dry weight ratio, FITC-labeled dextran permeability, histopathology, and soluble RAGE were determined. RESULTS: VILI was characterized by reduced PaO2/FiO2 ratio (low VT: 540 [381-661] vs. control: 693 [620-754], p < 0.05), increased wet-to-dry weight ratio (low VT: 4.8 [4.6-4.9] vs. control: 4.5 [4.4-4.6], p < 0.05), pneumonia (low VT: 30 [0-58] vs. control: 0 [0-0]%, p < 0.05) and interstitial inflammation (low VT: 2 [1-3] vs. control: 1 [0-1], p < 0.05). FG-3154 did not affect wet-to-dry weight ratio (mod VT + FG-3154: 4.8 [4.7-5.0] vs. mod VT + vehicle: 4.8 [4.8-5.0], p > 0.99), extravasated dextrans (mod VT + FG-3154: 0.06 [0.04-0.09] vs. mod VT + vehicle: 0.04 [0.03-0.09] µg/mg tissue, p > 0.99), sRAGE (mod VT + FG-3154: 1865 [1628-2252] vs. mod VT + vehicle: 1885 [1695-2159] pg/mL, p > 0.99) or histopathology. CONCLUSIONS: 'Double hit' VILI was characterized by inflammation, impaired oxygenation, pulmonary edema and histopathological lung injury. Blocking CTGF does not improve oxygenation nor reduce pulmonary edema in rats with VILI.
Assuntos
Fator de Crescimento do Tecido Conjuntivo , Edema Pulmonar , Lesão Pulmonar Induzida por Ventilação Mecânica , Animais , Lesão Pulmonar Induzida por Ventilação Mecânica/tratamento farmacológico , Lesão Pulmonar Induzida por Ventilação Mecânica/metabolismo , Lesão Pulmonar Induzida por Ventilação Mecânica/patologia , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Fator de Crescimento do Tecido Conjuntivo/antagonistas & inibidores , Ratos , Masculino , Edema Pulmonar/etiologia , Edema Pulmonar/metabolismo , Anticorpos Neutralizantes/farmacologia , Ratos Sprague-Dawley , Pulmão/patologia , Pulmão/metabolismo , Modelos Animais de Doenças , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Receptor para Produtos Finais de Glicação Avançada/antagonistas & inibidoresRESUMO
As the irreversible products of the non-enzymatic reduction of sugars and the amino groups of proteins or peptides, advanced glycation end products (AGEs) are metabolized and excreted via the kidneys. However, if AGEs are not metabolized, they are deposited in the kidneys and bind to AGE receptors (RAGE), which can induce various pathological changes, including oxidative stress, apoptosis, and inflammation. This study used the D-galactose (DG)-induced rat model to explore the potential role and mechanism of L-theanine in inhibiting AGEs/RAGE-related signaling pathways in renal tissues. L-theanine increased the activities of glutathione peroxidase (GSH-Px) and total antioxidant capacity (T-AOC) while downregulating the contents of malondialdehyde (MDA) and AGEs in renal tissues induced by DG (P < 0.05). By inhibiting the upregulation of RAGE protein expression attributed to AGEs accumulation (P < 0.05), L-theanine downregulated phosphorylated nuclear factor (p-NF-κB (p65)), Bax, and cleaved-caspase-3 expression and increased Bcl-2 protein expression (P < 0.05), thereby alleviating the oxidative stress damage and reducing the inflammation and cell injury induced by DG. In addition, the Congo red staining section of renal tissue also showed that the natural product L-theanine can protect against AGEs-induced renal damage in DG-induced rat model.
Assuntos
Galactose , Glutamatos , Produtos Finais de Glicação Avançada , Receptor para Produtos Finais de Glicação Avançada , Animais , Galactose/farmacologia , Glutamatos/farmacologia , Produtos Finais de Glicação Avançada/antagonistas & inibidores , Produtos Finais de Glicação Avançada/metabolismo , Inflamação/metabolismo , Rim/metabolismo , Estresse Oxidativo , Ratos , Receptor para Produtos Finais de Glicação Avançada/antagonistas & inibidores , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Transdução de Sinais/efeitos dos fármacosRESUMO
Idiopathic pulmonary fibrosis (IPF) is an interstitial lung disease characterised by irreversible fibrosis and destruction of the alveolar structure. Receptor for advanced glycation end products (RAGE) has been identified as one of the key molecules involved in IPF pathogenesis. A RAGE-antagonist peptide (RAP) was developed based on the RAGE-binding domain of high mobility group box-1 (HMGB-1). Anti-IPF effects of RAP were evaluated in a bleomycin-induced mouse model of IPF. Bleomycin was administered intratracheally, and then RAP was administrated twice by intratracheal instillation, 1 and 3 d after bleomycin challenge. Seven days after the bleomycin challenge, the mice were sacrificed and the lungs were harvested. The results showed that pulmonary hydroxyproline was reduced in mice administered RAP compared with the control group. Tumour growth factor-ß (TGF-ß), α-smooth muscle actin (α-SMA) and collagen were also reduced by RAP administration in a dose-dependent manner. Longer-term effects of RAP were investigated in mice challenged with bleomycin. RAP was administered intratracheally every 7 d for 28 d, after which lung samples were harvested and analysed. The results showed that hydroxyproline, TGF-ß, α-SMA and collagen were reduced by repeated RAP administration. Taken together, the results suggest that RAP is useful for treatment of IPF.
Assuntos
Fibrose Pulmonar , Receptor para Produtos Finais de Glicação Avançada , Animais , Bleomicina/efeitos adversos , Colágeno , Modelos Animais de Doenças , Hidroxiprolina/metabolismo , Pulmão , Camundongos , Camundongos Endogâmicos C57BL , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/tratamento farmacológico , Receptor para Produtos Finais de Glicação Avançada/antagonistas & inibidores , Fator de Crescimento Transformador beta/metabolismoRESUMO
Resection of brain tumors frequently causes injury to the surrounding brain tissue that exacerbates cerebral edema by activating an inflammatory cascade. Although corticosteroids are often utilized peri-operatively to alleviate the symptoms associated with brain edema, they increase operative morbidities and suppress the efficacy of immunotherapy. Thus, novel approaches to minimize cerebral edema caused by neurosurgical procedures will have significant utility in the management of patients with brain tumors. We have studied the role of the receptor for advanced glycation end products (RAGE) and its ligands on inflammatory responses to neurosurgical injury in mice and humans. Blood-brain barrier (BBB) integrity and neuroinflammation were characterized by Nanostring, flow cytometry, qPCR, and immunoblotting of WT and RAGE knockout mice brains subjected to surgical brain injury (SBI). Human tumor tissue and fluid collected from the resection cavity of patients undergoing craniotomy were also analyzed by single-cell RNA sequencing and ELISA. Genetic ablation of RAGE significantly abrogated neuroinflammation and BBB disruption in the murine SBI model. The inflammatory responses to SBI were associated with infiltration of S100A9-expressing myeloid-derived cells into the brain. Local release of pro-inflammatory S100A9 was confirmed in patients following tumor resection. RAGE and S100A9 inhibitors were as effective as dexamethasone in attenuating neuroinflammation. However, unlike dexamethasone and S100A9 inhibitor, RAGE inhibition did not diminish the efficacy of anti-PD-1 immunotherapy in glioma-bearing mice. These observations confirm the role of the RAGE axis in surgically induced neuroinflammation and provide an alternative therapeutic option to dexamethasone in managing post-operative cerebral edema.
Assuntos
Anti-Inflamatórios , Edema Encefálico , Neoplasias Encefálicas , Receptor para Produtos Finais de Glicação Avançada , Animais , Anti-Inflamatórios/farmacologia , Edema Encefálico/tratamento farmacológico , Edema Encefálico/etiologia , Lesões Encefálicas/complicações , Neoplasias Encefálicas/cirurgia , Dexametasona/uso terapêutico , Modelos Animais de Doenças , Humanos , Camundongos , Ratos , Ratos Sprague-Dawley , Receptor para Produtos Finais de Glicação Avançada/antagonistas & inibidoresRESUMO
BACKGROUND: Exposure to toluene diisocyanate (TDI) is a significant pathogenic factor for asthma. We previously reported that the receptor for advanced glycation end products (RAGE) plays a key role in TDI-induced asthma. Histone deacetylase (HDAC) has been reported to be important in asthmatic pathogenesis. However, its effect on TDI-induced asthma is not known. The aim of this study was to determine the role of RAGE and HDAC in regulating airway inflammation using a TDI-induced murine asthma model. METHODS: BALB/c mice were sensitized and challenged with TDI to establish an asthma model. FPS-ZM1 (RAGE inhibitor), JNJ-26482585 and romidepsin (HDAC inhibitors) were administered intraperitoneally before each challenge. In vitro, the human bronchial epithelial cell line 16HBE was stimulated with TDI-human serum albumin (TDI-HSA). RAGE knockdown cells were constructed and evaluated, and MK2006 (AKT inhibitor) was also used in the experiments. RESULTS: In TDI-induced asthmatic mice, the expression of RAGE, HDAC1, and p-AKT/t-AKT was upregulated, and these expressions were attenuated by FPS-ZM1. Airway reactivity, Th2 cytokine levels in lymph supernatant, IgE, airway inflammation, and goblet cell metaplasia were significantly increased in the TDI-induced asthmatic mice. These increases were suppressed by JNJ-26482585 and romidepsin. In addition, JNJ-26482585 and romidepsin ameliorated the redistribution of E-cadherin and ß-catenin in TDI-induced asthma. In TDI-HSA-stimulated 16HBE cells, knockdown of RAGE attenuated the upregulation of HDAC1 and phospho-AKT (p-AKT). Treatment with the AKT inhibitor MK2006 suppressed TDI-induced HDAC1 expression. CONCLUSIONS: These findings indicate that RAGE modulates HDAC1 expression via the PI3K/AKT pathway, and that inhibition of HDAC prevents TDI-induced airway inflammation.
Assuntos
Asma/prevenção & controle , Histona Desacetilase 1/metabolismo , Inflamação/prevenção & controle , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Asma/induzido quimicamente , Benzamidas/farmacologia , Linhagem Celular , Citocinas/metabolismo , Depsipeptídeos/farmacologia , Modelos Animais de Doenças , Histona Desacetilase 1/antagonistas & inibidores , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Fosfatidilinositol 3-Quinases/metabolismo , Receptor para Produtos Finais de Glicação Avançada/antagonistas & inibidores , Tolueno 2,4-Di-Isocianato/toxicidadeRESUMO
This study found two novel homogeneous polysaccharides from Angelica sinensis, APS-1I and APS-2II, binding to RAGE with a dissociation constant of 2.02 ± 0.2 and 85.92 ± 0.2 µM, respectively. APS-1I is a 17.0 kDa heteropolysaccharide, whose backbone is composed of α-1,6-Glcp, α-1,3,6-Glcp, α-1,2-Glcp, α-1,4-Galp, and α-1,3-Rhap, and whose two branches contain α-1,3,5-Araf, α-1,3-Araf, α-1,4-Galp, ß-1,3-Galp, and ß-1,4-Glcp. APS-2II is a 10.0 kDa linear glucan, that contains α-1,6-Glcp, α-1,3-Glcp, α-1,2-Glcp, and α-T-Glcp. In vitro, APS-1I demonstrated better promotion on glucose absorption and stronger repression on p-IRS-1 (Ser307), p-IRS-2 (Ser731), p-JNK, and p-P38 than APS-2II in insulin resistance (IR)-HepG2 cells. Furthermore, APS-1I treatment couldn't further decrease the inhibition on the phosphorylation of JNK and P38 produced by RAGE siRNA in IR-HepG2 cells. In vivo, APS-1I markedly improved IR and reversed the livers RAGE-JNK/p38-IRS signaling in high-fat-diet and streptozotocin-induced diabetic rats, suggesting that APS-1I could be a potential agent for improving IR in type 2 diabetes.
Assuntos
Angelica sinensis/química , Resistência à Insulina , Fígado/metabolismo , Polissacarídeos/química , Polissacarídeos/farmacologia , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Animais , Sequência de Carboidratos , Diabetes Mellitus Tipo 2/metabolismo , Glucose/metabolismo , Células Hep G2 , Humanos , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Insulina/metabolismo , Proteínas Substratos do Receptor de Insulina/metabolismo , Janus Quinases/metabolismo , Fígado/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases , Masculino , Polissacarídeos/metabolismo , Ratos , Ratos Sprague-Dawley , Receptor para Produtos Finais de Glicação Avançada/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismoRESUMO
Cellular and molecular mechanisms driving morbidity following SARS-CoV-2 infection have not been well defined. The receptor for advanced glycation end products (RAGE) is a central mediator of tissue injury and contributes to SARS-CoV-2 disease pathogenesis. In this study, we temporally delineated key cell and molecular events leading to lung injury in mice following SARS-CoV-2 infection and assessed efficacy of therapeutically targeting RAGE to improve survival. Early following infection, SARS-CoV-2 replicated to high titers within the lungs and evaded triggering inflammation and cell death. However, a significant necrotic cell death event in CD45- populations, corresponding with peak viral loads, was observed on day 2 after infection. Metabolic reprogramming and inflammation were initiated following this cell death event and corresponded with increased lung interstitial pneumonia, perivascular inflammation, and endothelial hyperplasia together with decreased oxygen saturation. Therapeutic treatment with the RAGE antagonist FPS-ZM1 improved survival in infected mice and limited inflammation and associated perivascular pathology. Together, these results provide critical characterization of disease pathogenesis in the mouse model and implicate a role for RAGE signaling as a therapeutic target to improve outcomes following SARS-CoV-2 infection.
Assuntos
Benzamidas/farmacologia , Tratamento Farmacológico da COVID-19 , COVID-19 , Pulmão , Receptor para Produtos Finais de Glicação Avançada , SARS-CoV-2/fisiologia , Transdução de Sinais/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos , Animais , COVID-19/genética , COVID-19/metabolismo , Modelos Animais de Doenças , Pulmão/metabolismo , Pulmão/virologia , Camundongos , Camundongos Transgênicos , Receptor para Produtos Finais de Glicação Avançada/antagonistas & inibidores , Receptor para Produtos Finais de Glicação Avançada/genética , Receptor para Produtos Finais de Glicação Avançada/metabolismoRESUMO
Diabetes is a group of metabolic diseases characterised by chronic hyperglycaemia caused by multiple causes, which is caused by insulin secretion and/or utilisation defects. It is characterised by increased fasting and postprandial blood glucose levels due to insulin deficiency or insulin resistance. It is reported that the harm of diabetes mainly comes from its complications, and the cardiovascular disease caused by diabetes is the primary cause of its harm. China has the largest number of diabetic patients in the world, and the prevention and control of diabetes are facing great challenges. In recent years, many kinds of literature have been published abroad, which have proved that coumarin and its derivatives are effective in the treatment of diabetic complications such as nephropathy and cardiovascular disease. In this paper, the types of antidiabetic drugs and the anti-diabetic mechanism of coumarins were reviewed.
Assuntos
Cumarínicos/farmacologia , Complicações do Diabetes/tratamento farmacológico , Diabetes Mellitus/tratamento farmacológico , Hipoglicemiantes/farmacologia , Animais , Cumarínicos/síntese química , Cumarínicos/química , Complicações do Diabetes/metabolismo , Diabetes Mellitus/metabolismo , Humanos , Hipoglicemiantes/síntese química , Hipoglicemiantes/química , PPAR gama/antagonistas & inibidores , PPAR gama/metabolismo , Receptor para Produtos Finais de Glicação Avançada/antagonistas & inibidores , Receptor para Produtos Finais de Glicação Avançada/metabolismo , alfa-Glucosidases/metabolismoRESUMO
The receptor for advanced glycation end products (RAGE) is a member of the immunoglobulin family that is overexpressed in several cancers. RAGE is highly expressed in the lung, and its expression increases proportionally at the site of inflammation. This receptor can bind a variety of ligands, including advanced glycation end products, high mobility group box 1, S100 proteins, adhesion molecules, complement components, advanced lipoxidation end products, lipopolysaccharides, and other molecules that mediate cellular responses related to acute and chronic inflammation. RAGE serves as an important node for the initiation and stimulation of cell stress and growth signaling mechanisms that promote carcinogenesis, tumor propagation, and metastatic potential. In this review, we discuss different aspects of RAGE and its prominent ligands implicated in cancer pathogenesis and describe current findings that provide insights into the significant role played by RAGE in cancer. Cancer development can be hindered by inhibiting the interaction of RAGE with its ligands, and this could provide an effective strategy for cancer treatment.
Assuntos
Neoplasias , Receptor para Produtos Finais de Glicação Avançada , Humanos , Produtos Finais de Glicação Avançada/metabolismo , Inflamação/metabolismo , Ligantes , Neoplasias/tratamento farmacológico , Receptor para Produtos Finais de Glicação Avançada/antagonistas & inibidoresRESUMO
Monoamine oxidase (MAO) is rapidly gaining appreciation for its pathophysiologic role in cardiac injury and failure. Oxidative deamination of norepinephrine by MAO generates H2O2 and the catecholaldehyde 3,4-dihydroxyphenylglycolaldehyde (DOPEGAL), the latter of which is a highly potent and reactive electrophile that has been linked to cardiotoxicity. However, many questions remain as to whether catecholaldehydes regulate basic physiological processes in the myocardium and the pathways involved. Here, we examined the role of MAO-derived oxidative metabolites in mediating the activation of cardiac fibroblasts in response to norepinephrine. In neonatal murine cardiac fibroblasts, norepinephrine increased reactive oxygen species (ROS), accumulation of catechol-modified protein adducts, expression and secretion of collagens I/III, and other markers of profibrotic activation including STAT3 phosphorylation. These effects were attenuated with MAO inhibitors, the aldehyde-scavenging dipeptide l-carnosine, and FPS-ZM1, an antagonist for the receptor for advanced glycation endproducts (RAGE). Interestingly, treatment of cardiac fibroblasts with a low dose (1 µM) of DOPEGAL-modified albumin phenocopied many of the effects of norepinephrine and also induced an increase in RAGE expression. Higher doses (>10 µM) of DOPEGAL-modified albumin were determined to be toxic to cardiac fibroblasts in a RAGE-dependent manner, which was mitigated by l-carnosine. Collectively, these findings suggest that norepinephrine may influence extracellular matrix remodeling via an adrenergic-independent redox pathway in cardiac fibroblasts involving the MAO-mediated generation of ROS, catecholaldehydes, and RAGE. Furthermore, since elevations in the catecholaminergic tone and oxidative stress in heart disease are linked with cardiac fibrosis, this study illustrates novel drug targets that could potentially mitigate this serious disorder.
Assuntos
Miofibroblastos/efeitos dos fármacos , Norepinefrina/farmacologia , Norepinefrina/toxicidade , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Animais , Células Cultivadas , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/metabolismo , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Camundongos , Estrutura Molecular , Monoaminoxidase/metabolismo , Inibidores da Monoaminoxidase/farmacologia , Miofibroblastos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Receptor para Produtos Finais de Glicação Avançada/antagonistas & inibidoresRESUMO
A detrimental role of the receptor for the advanced glycation end product (RAGE) has been identified in the immune response, and various pathological conditions and its V and C1 domains in the extracellular region of RAGE are believed to be the main ligand-binding domains. Consequently, specific inhibitors targeting those domains could be of clinical value in fighting against the pathological condition associated with RAGE over-activation. Single-domain antibodies, also called nanobodies (Nbs), are antibody fragments engineered from the heavy-chain only antibodies found in camelids, which offer a range of advantages in therapy. In this study, we report the development and characterization of the V-C1 domain-specific Nbs. Three Nbs (3CNB, 4BNB, and 5ENB) targeting V-C1 domain of human RAGE were isolated from an immunized alpaca using a phage display. All of these Nbs revealed high thermostability. 3CNB, 4BNB, and 5ENB bind to V-C1 domain with a dissociation constant (KD) of 27.25, 39.37, and 47.85 nM, respectively, using Isothermal Titration Calorimetry (ITC). After homodimerization using human IgG1-Fc fusion, their binding affinity improved to 0.55, 0.62, and 0.41 nM, respectively, using Surface Plasmon Resonance (SPR). Flow cytometry showed all the Fc fusions Nbs can bind to human RAGE expressed on the cell surface. Competitive ELISA further confirmed their V-C1-hS100B blocking ability in solution, providing insights into the applicability of Nbs in treating RAGE-associated diseases.
Assuntos
Produtos Finais de Glicação Avançada/química , Fragmentos Fc das Imunoglobulinas/química , Imunoglobulina G/química , Receptor para Produtos Finais de Glicação Avançada/química , Proteínas Recombinantes de Fusão/química , Anticorpos de Domínio Único/biossíntese , Sequência de Aminoácidos , Animais , Sítios de Ligação , Camelídeos Americanos , Clonagem Molecular , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Produtos Finais de Glicação Avançada/genética , Produtos Finais de Glicação Avançada/imunologia , Células HEK293 , Humanos , Fragmentos Fc das Imunoglobulinas/genética , Fragmentos Fc das Imunoglobulinas/imunologia , Imunoglobulina G/genética , Imunoglobulina G/imunologia , Biblioteca de Peptídeos , Ligação Proteica , Domínios Proteicos , Domínios e Motivos de Interação entre Proteínas , Multimerização Proteica , Receptor para Produtos Finais de Glicação Avançada/antagonistas & inibidores , Receptor para Produtos Finais de Glicação Avançada/genética , Receptor para Produtos Finais de Glicação Avançada/imunologia , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Anticorpos de Domínio Único/química , Anticorpos de Domínio Único/isolamento & purificaçãoRESUMO
Hyperglycemia-associated advanced glycation end products (AGEs) and the receptor for AGE (RAGE) contribute to nonalcoholic fatty liver disease (NAFLD). Xanthohumol (XH) exhibits protective activities against liver diseases. Aim: To investigate the effects of XH on Type II diabetes mellitus (T2DM)-induced liver steatosis and fibrosis. Methods: NAFLD rat models were duplicated. Biomolecular markers were detected. Quantitative real-time PCR (RT-PCR) and western blot were used to detect mRNA and protein expression. Immunofluorescence assays were employed to identify the subcellular locations. Results: XH significantly ameliorated hyperglycemia and hyperlipidemia in rats. XH attenuated the expression of RAGE and NF-κB signaling. XH significantly alleviated inflammation and oxidation by upregulating NRF2 expression. Knockdown of NRF2 blocked XH protection in hepatocytes. Conclusion: XH protected against T2DM-induced liver steatosis and fibrosis by mediating NRF2/AGE/RAGE/NF-κB signaling.
Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Fígado Gorduroso/tratamento farmacológico , Fibrose/tratamento farmacológico , Flavonoides/farmacologia , Hipoglicemiantes/farmacologia , Propiofenonas/farmacologia , Animais , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/induzido quimicamente , Diabetes Mellitus Tipo 2/metabolismo , Fígado Gorduroso/induzido quimicamente , Fígado Gorduroso/metabolismo , Fibrose/induzido quimicamente , Fibrose/metabolismo , Flavonoides/administração & dosagem , Hipoglicemiantes/administração & dosagem , Injeções Intraperitoneais , Masculino , Fator 2 Relacionado a NF-E2/antagonistas & inibidores , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Propiofenonas/administração & dosagem , Ratos , Ratos Sprague-Dawley , Receptor para Produtos Finais de Glicação Avançada/antagonistas & inibidores , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Transdução de Sinais/efeitos dos fármacos , EstreptozocinaRESUMO
Basigin (CD147) is a transmembrane glycoprotein that regulates several physiological processes, including the production and activity of matrix metalloproteinases (MMPs). The activity of CD147 depends mainly on its glycosylation, which varies among pathophysiological conditions. However, it is unknown whether CD147 activity or its function in MMP regulation are affected by the diabetic environment, which is characterized by high glucose (HG) levels and an excess of glycation end products (AGEs). In this study, we investigated the effect of HG and AGEs on CD147 expression in human adipocytes. We also examined the mediating role of nuclear factor kappa B (NFκB) and receptor of AGE (RAGE) to this effect. Our findings show that carboxymethyl lysine and HG increased CD147 expression and glycosylation, which was accompanied by increases in MMP2 and MMP9 expression and activity, as well as upregulations of the N-acetylglucosaminyltransferase, MGAT5. These effects were abolished by NFκB and RAGE inhibition, CD147 gene silencing, and by the glycosylation inhibitor, tunicamycin. In conclusion, the current findings indicate that AGEs and HG induce CD147 expression and glycosylation in adipocytes, with possible mediation by NFκB and RAGE. One of the critical outcomes of this pathway is augmented MMP activity known to contribute to cardiovascular complications in diabetes.
Assuntos
Adipócitos/efeitos dos fármacos , Basigina/metabolismo , Glucose/farmacologia , Produtos Finais de Glicação Avançada/farmacologia , Metaloproteinases da Matriz/metabolismo , Adipócitos/metabolismo , Basigina/genética , Células Cultivadas , Inativação Gênica , Glicosilação/efeitos dos fármacos , Humanos , N-Acetilglucosaminiltransferases/genética , N-Acetilglucosaminiltransferases/metabolismo , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Receptor para Produtos Finais de Glicação Avançada/antagonistas & inibidores , Receptor para Produtos Finais de Glicação Avançada/metabolismoRESUMO
The receptor for advanced glycation end-products (RAGE) has been implicated in the pathophysiology of chronic obstructive pulmonary disease (COPD). However, it is still unknown whether RAGE directly contributes to alveolar epithelial damage and abnormal repair responses. We hypothesize that RAGE activation not only induces lung tissue damage but also hampers alveolar epithelial repair responses. The effects of the RAGE ligands LL-37 and HMGB1 were examined on airway inflammation and alveolar tissue damage in wild-type and RAGE-deficient mice and on lung damage and repair responses using murine precision cut lung slices (PCLS) and organoids. In addition, their effects were studied on the repair response of human alveolar epithelial A549 cells, using siRNA knockdown of RAGE and treatment with the RAGE inhibitor FPS-ZM1. We observed that intranasal installation of LL-37 and HMGB1 induces RAGE-dependent inflammation and severe alveolar tissue damage in mice within 6 h, with stronger effects in a mouse strain susceptible for emphysema compared with a nonsusceptible strain. In PCLS, RAGE inhibition reduced the recovery from elastase-induced alveolar tissue damage. In organoids, RAGE ligands reduced the organoid-forming efficiency and epithelial differentiation into pneumocyte-organoids. Finally, in A549 cells, we confirmed the role of RAGE in impaired repair responses upon exposure to LL-37. Together, our data indicate that activation of RAGE by its ligands LL-37 and HMGB1 induces acute lung tissue damage and that this impedes alveolar epithelial repair, illustrating the therapeutic potential of RAGE inhibitors for lung tissue repair in emphysema.
Assuntos
Células Epiteliais Alveolares/patologia , Peptídeos Catiônicos Antimicrobianos/metabolismo , Proteína HMGB1/metabolismo , Alvéolos Pulmonares/lesões , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Células A549 , Animais , Benzamidas/farmacologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Organoides/efeitos dos fármacos , Elastase Pancreática/toxicidade , Doença Pulmonar Obstrutiva Crônica/patologia , Receptor para Produtos Finais de Glicação Avançada/antagonistas & inibidores , Regeneração/fisiologia , CatelicidinasRESUMO
Receptor for advanced glycation end-products (RAGE) is a member of the immunoglobulin superfamily. RAGE binds and mediates cellular responses to a range of DAMPs (damage-associated molecular pattern molecules), such as AGEs, HMGB1, and S100/calgranulins, and as an innate immune sensor, can recognize microbial PAMPs (pathogen-associated molecular pattern molecules), including bacterial LPS, bacterial DNA, and viral and parasitic proteins. RAGE and its ligands stimulate the activations of diverse pathways, such as p38MAPK, ERK1/2, Cdc42/Rac, and JNK, and trigger cascades of diverse signaling events that are involved in a wide spectrum of diseases, including diabetes mellitus, inflammatory, vascular and neurodegenerative diseases, atherothrombosis, and cancer. Thus, the targeted inhibition of RAGE or its ligands is considered an important strategy for the treatment of cancer and chronic inflammatory diseases.
Assuntos
Descoberta de Drogas , Terapia de Alvo Molecular , Receptor para Produtos Finais de Glicação Avançada/antagonistas & inibidores , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Animais , Suscetibilidade a Doenças , Produtos Finais de Glicação Avançada/metabolismo , Humanos , Ligantes , Modelos Moleculares , Polimorfismo Genético , Isoformas de Proteínas , Receptor para Produtos Finais de Glicação Avançada/química , Receptor para Produtos Finais de Glicação Avançada/genética , Transdução de Sinais/efeitos dos fármacos , Relação Estrutura-AtividadeRESUMO
The Receptor for Advanced Glycation End products (RAGE) is a pattern recognition receptor that signals for inflammation via the NF-κB pathway. RAGE has been pursued as a potential target to suppress symptoms of diabetes and is of interest in a number of other diseases associated with chronic inflammation, such as inflammatory bowel disease and bronchopulmonary dysplasia. Screening and optimization have previously produced small molecules that inhibit the activity of RAGE in cell-based assays, but efforts to develop a therapeutically viable direct-binding RAGE inhibitor have yet to be successful. Here, we show that a fragment-based approach can be applied to discover fundamentally new types of RAGE inhibitors that specifically target the ligand-binding surface. A series of systematic assays of structural stability, solubility, and crystallization were performed to select constructs of the RAGE ligand-binding domain and optimize conditions for NMR-based screening and co-crystallization of RAGE with hit fragments. An NMR-based screen of a highly curated ~14 000-member fragment library produced 21 fragment leads. Of these, three were selected for elaboration based on structure-activity relationships generated through cycles of structural analysis by X-ray crystallography, structure-guided design principles, and synthetic chemistry. These results, combined with crystal structures of the first linked fragment compounds, demonstrate the applicability of the fragment-based approach to the discovery of RAGE inhibitors.
Assuntos
Benzamidas/química , Desenho de Fármacos/métodos , Imidazóis/química , Receptor para Produtos Finais de Glicação Avançada/antagonistas & inibidores , Bibliotecas de Moléculas Pequenas/química , Benzamidas/metabolismo , Benzamidas/farmacologia , Sítios de Ligação , Clonagem Molecular , Cristalografia por Raios X , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Humanos , Imidazóis/metabolismo , Imidazóis/farmacologia , Ligantes , Modelos Moleculares , Mutagênese Sítio-Dirigida , Ressonância Magnética Nuclear Biomolecular , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Receptor para Produtos Finais de Glicação Avançada/química , Receptor para Produtos Finais de Glicação Avançada/genética , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Bibliotecas de Moléculas Pequenas/metabolismo , Bibliotecas de Moléculas Pequenas/farmacologia , Relação Estrutura-AtividadeRESUMO
Pancreatic ductal adenocarcinoma (PDAC) remains a very difficult cancer to treat. Recent in vitro and in vivo studies suggest that the activation of the receptor for advanced glycation end products (RAGE) by its ligands stimulates pancreatic cancer cell proliferation and tumor growth. Additional studies show that, in the RAGE ligand, the high mobility group box 1 (HMGB1) protein plays an important role in chemoresistance against the cytotoxic agent gemcitabine by promoting cell survival through increased autophagy. We hypothesized that blocking the RAGE/HMGB1 interaction would enhance the cytotoxic effect of gemcitabine by reducing cell survival and autophagy. Using a preclinical mouse model of PDAC and a monoclonal antibody (IgG 2A11) as a RAGE inhibitor, we demonstrate that RAGE inhibition concurrent with gemcitabine treatment enhanced the cytotoxic effect of gemcitabine. The combination of IgG 2A11 and gemcitabine resulted in decreased autophagy compared to treatment with gemcitabine combined with control antibodies. Notably, we also observed that RAGE inhibition protected against excessive weight loss during treatment with gemcitabine. Our data suggest that the combination of gemcitabine with a RAGE inhibitor could be a promising therapeutic approach for the treatment of pancreatic cancer and needs to be further investigated.
Assuntos
Autofagia/efeitos dos fármacos , Desoxicitidina/análogos & derivados , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Desoxicitidina/farmacologia , Desoxicitidina/uso terapêutico , Proteína HMGB1/metabolismo , Camundongos , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Poli(ADP-Ribose) Polimerases/metabolismo , Receptor para Produtos Finais de Glicação Avançada/antagonistas & inibidores , Receptor para Produtos Finais de Glicação Avançada/imunologia , Transplante Homólogo , GencitabinaRESUMO
BACKGROUND: Liver fibrosis is defined as the accumulation of the extracellular matrix and scar formation. The receptor for advanced glycation end products (RAGE) has been demonstrated to participate in fibrogenesis. S100B is a ligand of RAGE and exerts extracellular functions by inducing a series of signal transduction cascades. However, the involvement of S100B and RAGE in cholestasis-induced liver fibrosis remains unclear. In this study, we investigated S100B and RAGE expression during liver fibrosis in mice that underwent common bile duct ligation (BDL). METHODS: BDL was performed in 10-week-old male C57BL/6J mice with sham control (n = 26) and BDL (n = 26) groups. Expression levels of S100B, RAGE and fibrotic markers in the livers from both groups at week 1 and 3 after BDL were examined by western blot and quantitative real-time reverse transcription polymerase chain reaction analysis. Liver fibrotic changes were examined by histological and ultrastructural analysis. RESULTS: Histological staining with Sirius Red and the evaluation of the messenger RNA expression of fibrotic markers showed noticeable periportal fibrosis and bile duct proliferation. S100B was mainly present in bile duct epithelial cells, and its expression was upregulated in proportion to the ductular reaction during fibrogenesis by BDL. RAGE expression was also increased, and interestingly, triple immunofluorescence staining and transmission electron microscopy showed that both S100B and RAGE were expressed in proliferating bile duct epithelial cells and activated hepatic stellate cells (HSCs) of the BDL livers. In addition, in rat HSCs (HSC-T6), treatment with recombinant S100B protein significantly increased fibrotic markers in a dose-dependent manner, and RAGE small interfering RNA (siRNA) suppressed S100B-stimulated upregulation of fibrotic markers compared with cells treated with scramble siRNA and S100B. CONCLUSION: These findings suggest that the increased expression of S100B and RAGE and the interaction between S100B and RAGE may play an important role in ductular reaction and liver fibrosis induced by BDL.
Assuntos
Cirrose Hepática/patologia , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Subunidade beta da Proteína Ligante de Cálcio S100/metabolismo , Animais , Ductos Biliares/citologia , Ductos Biliares/cirurgia , Linhagem Celular , Modelos Animais de Doenças , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Células Estreladas do Fígado/citologia , Células Estreladas do Fígado/metabolismo , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Interferência de RNA , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/metabolismo , Ratos , Receptor para Produtos Finais de Glicação Avançada/antagonistas & inibidores , Receptor para Produtos Finais de Glicação Avançada/genética , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/farmacologia , Subunidade beta da Proteína Ligante de Cálcio S100/genética , Subunidade beta da Proteína Ligante de Cálcio S100/farmacologia , Regulação para Cima/efeitos dos fármacosRESUMO
Thoracic dorsal root ganglia (tDRG) contribute to fluid secretion in the upper airways. Inflammation potentiates DRG responses, but the mechanisms remain under investigation. The receptor for advanced glycation end-products (RAGE) underlies potentiation of DRG responses in pain pathologies; however, its role in other sensory modalities is less understood. We hypothesize that RAGE contributes to electrophysiological and biochemical changes in tDRGs during inflammation. We used tDRGs and tracheas from wild types (WT), RAGE knock-out (RAGE-KO), and with the RAGE antagonist FPS-ZM1, and exposed them to lipopolysaccharides (LPS). We studied: capsaicin (CAP)-evoked currents and action potentials (AP), tracheal submucosal gland secretion, RAGE expression and downstream pathways. In WT neurons, LPS increased CAP-evoked currents and AP generation, and it caused submucosal gland hypersecretion in tracheas from WT mice exposed to LPS. In contrast, LPS had no effect on tDRG excitability or gland secretion in RAGE-KO mice or mice treated with FPS-ZM1. LPS upregulated full-length RAGE (encoded by Tv1-RAGE) and downregulated a soluble (sRAGE) splice variant (encoded by MmusRAGEv4) in tDRG neurons. These data suggest that sensitization of tDRG neurons contributes to hypersecretion in the upper airways during inflammation. And at least two RAGE variants may be involved in these effects of LPS.