RESUMO
Drug delivery systems such as liposomes are widely used to stabilize and increase the plasma half-life of therapeutics. In this article, we have investigated two strategies to increase the half-life of deoxyribonuclease I, an FDA-approved enzyme used for the treatment of cystic fibrosis, and a potential candidate for the reduction of uncontrolled inflammation induced by neutrophil extracellular traps. We demonstrate that our optimized preparation procedure resulted in nanoparticles with improved plasma half-life and total exposure relative to native protein, while maintaining enzymatic activity.
Assuntos
Armadilhas Extracelulares , Nanopartículas , Desoxirribonuclease I/farmacologia , Armadilhas Extracelulares/metabolismo , Meia-Vida , Lipossomos/metabolismoRESUMO
CD36 is a multiligand receptor involved in lipid metabolism. We investigated the mechanisms underlying the cardioprotective effect of CP-3(iv), an azapeptide belonging to a new class of selective CD36 ligands. The role of CP-3(iv) in mediating cardioprotection was investigated because CD36 signaling leads to activation of peroxisome proliferator-activated receptor-γ, a transcriptional regulator of adiponectin. CP-3(iv) pretreatment reduced infarct size by 54% and preserved hemodynamics in C57BL/6 mice subjected to 30 min coronary ligation and reperfusion but had no effect in CD36-deficient mice. The effects of CP-3(iv) were associated with an increase in circulating adiponectin levels, epididymal fat adiponectin gene expression, and adiponectin transcriptional regulators ( Pparg, Cebpb, Sirt1) after 6 h of reperfusion. Reduced myocardial oxidative stress and apoptosis were observed along with an increase in expression of myocardial adiponectin target proteins, including cyclooxygenase-2, phospho-AMPK, and phospho-Akt. Moreover, CP-3(iv) increased myocardial performance in isolated hearts, whereas blockade of adiponectin with an anti-adiponectin antibody abrogated it. CP-3(iv) exerts cardioprotection against myocardial ischemia and reperfusion (MI/R) injury and dysfunction, at least in part, by increasing circulating and myocardial adiponectin levels. Hence, both paracrine and endocrine effects of adiponectin may contribute to reduced reactive oxygen species generation and apoptosis after MI/R, in a CD36-dependent manner.-Huynh, D. N., Bessi, V. L., Ménard, L., Piquereau, J., Proulx, C., Febbraio, M., Lubell, W. D., Carpentier, A. C., Burelle, Y., Ong, H., Marleau, S. Adiponectin has a pivotal role in the cardioprotective effect of CP-3(iv), a selective CD36 azapeptide ligand, after transient coronary artery occlusion in mice.
Assuntos
Adiponectina/biossíntese , Antígenos CD36/agonistas , Cardiotônicos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Miocárdio/metabolismo , Peptídeos/farmacologia , Animais , Modelos Animais de Doenças , Camundongos , Camundongos Knockout , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Miocárdio/patologia , Estresse Oxidativo/efeitos dos fármacosRESUMO
QRFP (RFamide) peptides are neuropeptides involved in food intake and adiposity regulation in rodents. We have previously shown that QRFP-43 (43RFa) and QRFP-26 (26RFa) inhibited isoproterenol (ISO)-induced lipolysis in adipocytes. However, the antilipolytic signaling pathways activated by QRFP peptides have not been investigated. In the present study, 3T3-L1 adipocytes were used to identify the main pathways involved in QRFP-43 decreasing ISO-induced lipolysis. Our results show that QRFP-43 reduced ISO-induced phosphorylation of perilipin A (PLIN) and hormone-sensitive lipase (HSL) on Ser660 by 43 and 25%, respectively, but increased Akt phosphorylation by 44%. However, the inhibition of phosphodiesterase 3B (PDE3B), a regulator of lipolysis activated by Akt, did not reverse the antilipolytic effect of QRFP-43. PDE3B inhibition reversed the decrease of Ser660 HSL phosphorylation associated with QRFP-43 antilipolytic effect. QRFP-43 also prevented PKC activation and ISO-induced Src kinases activation leading to the inhibition of the caveolin-1 (CAV-1) translocation on lipid droplets. Indeed, QRFP-43 attenuated phorbol 12-myristate 13-acetate-induced lipolysis and ISO-induced extracellular signal-regulated and Src kinases by 28, 37 and 48%, respectively. The attenuation of ISO-induced lipolysis by QRFP-43 was associated with a decrease of phosphorylated Ser660 HSL, PKA-catalytic (PKA-c) subunit and CAV-1 translocation on lipid droplets by 37, 50 and 46%, respectively. The decrease in ISO-induced CAV-1 and PKA-c translocation was associated with a reduction of PLIN phosphorylation by 44% in QRFP-43-treated adipocytes. These results suggest that QRFP-43 attenuated ISO-induced lipolysis by preventing the formation of an active complex on lipid droplets and the activation of Src kinases and PKC.
Assuntos
Adipócitos/efeitos dos fármacos , Proteínas de Transporte/metabolismo , Caveolina 1/metabolismo , Subunidades Catalíticas da Proteína Quinase Dependente de AMP Cíclico/metabolismo , Lipólise/efeitos dos fármacos , Peptídeos/farmacologia , Fosfoproteínas/metabolismo , Esterol Esterase/metabolismo , Células 3T3-L1 , Adipócitos/enzimologia , Animais , Nucleotídeo Cíclico Fosfodiesterase do Tipo 3/metabolismo , Relação Dose-Resposta a Droga , Ativação Enzimática , Peptídeos e Proteínas de Sinalização Intercelular , Isoproterenol/farmacologia , Gotículas Lipídicas/efeitos dos fármacos , Gotículas Lipídicas/metabolismo , Camundongos , Complexos Multiproteicos , Perilipina-1 , Inibidores da Fosfodiesterase 3/farmacologia , Fosforilação , Proteína Quinase C/metabolismo , Transporte Proteico , Receptores Acoplados a Proteínas G/metabolismo , Serina , Transdução de Sinais/efeitos dos fármacos , Acetato de Tetradecanoilforbol/farmacologia , Quinases da Família src/metabolismoRESUMO
The scientific and medical community faced an unprecedented global health hazard that led to nearly 7 million deaths attributable to the rapid spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. In spite of the development of efficient vaccines against SARS-CoV-2, many people remain at risk of developing severe symptoms as the virus continues to spread without beneficial patient therapy. The hyper-inflammatory response to SARS-CoV-2 infection progressing to acute respiratory distress syndrome remains an unmet medical need for improving patient care. The viral infection stimulates alveolar macrophages to adopt an inflammatory phenotype regulated, at least in part, by the cluster of differentiation 36 receptor (CD36) to produce unrestrained inflammatory cytokine secretions. We suggest herein that the modulation of the macrophage response using the synthetic CD36 ligand hexarelin offers potential as therapy for halting respiratory failure in SARS-CoV-2-infected patients.
RESUMO
BACKGROUND: Atherosclerosis is triggered by the retention of apolipoprotein B-containing lipoproteins by proteoglycans. In addition to low-density lipoprotein, remnant lipoproteins have emerged as pivotal contributors to this pathology, particularly in the context of insulin resistance and diabetes. We have previously reported antiatherogenic properties of a monoclonal antibody (chP3R99) that recognizes sulfated glycosaminoglycans on arterial proteoglycans. METHODS AND RESULTS: Solid-phase assays demonstrated that chP3R99 effectively blocked >50% lipoprotein binding to chondroitin sulfate and vascular extracellular matrix in vitro. The preperfusion of chP3R99 (competitive effect) resulted in specific antibody-arterial accumulation and reduced fluorescent lipoprotein retention by ~60% in insulin resistant JCR:LA-cp rats. This competitive reduction was dose dependent (25-250 µg/mL), effectively decreasing deposition of cholesterol associated with lipoproteins. In a 5-week vaccination study in insulin resistant rats with (200 µg subcutaneously, once a week), chP3R99 reduced arterial lipoprotein retention, and was associated with the production of antichondroitin sulfate antibodies (Ab3) able to accumulate in the arteries (dot-blot). Neither the intravenous inoculation of chP3R99 (4.5 mg/kg), nor the immunization with this antibody displayed adverse effects on lipid or glucose metabolism, insulin resistance, liver function, blood cell indices, or inflammation pathways in JCR:LA-cp rats. CONCLUSIONS: Both acute (passive) and long-term administration (idiotypic cascade) of chP3R99 antibody reduced low-density lipoprotein and remnant lipoprotein interaction with proteoglycans in an insulin-resistant setting. These findings support the innovative approach of targeting proatherogenic lipoprotein retention by chP3R99 as a passive therapy or as an idiotypic vaccine for atherosclerosis.
Assuntos
Anticorpos Monoclonais , Aterosclerose , Resistência à Insulina , Lipoproteínas , Animais , Aterosclerose/prevenção & controle , Aterosclerose/imunologia , Aterosclerose/metabolismo , Ratos , Anticorpos Monoclonais/farmacologia , Masculino , Lipoproteínas/imunologia , Modelos Animais de Doenças , Vacinas/imunologia , Fatores de TempoRESUMO
Insufficient oxygen delivery to organs leads to tissue dysfunction and cell death. Reperfusion, although vital to organ survival, initiates an inflammatory response that may both aggravate local tissue injury and elicit remote organ damage. Polymorphonuclear neutrophil (PMN) trafficking to remote organs following ischaemia/reperfusion (I/R) is associated with the release of lipid mediators, including leucotriene (LT) B4 , cysteinyl-LTs (CysLTs) and platelet-activating factor (PAF). Yet, their potentially cooperative role in regulating I/R-mediated inflammation has not been thoroughly assessed. The present study aimed to determine the cooperative role of lipid mediators in regulating PMN migration, tissue oedema and injury using selective receptor antagonists in selected models of I/R and dermal inflammation. Our results show that rabbits, pre-treated orally with BIIL 284 and/or WEB 2086 and MK-0571, were protected from remote tissue injury following I/R or dermal inflammation in an additive or synergistic manner when the animals were pre-treated with two drugs concomitantly. The functional selectivity of the antagonists towards their respective agonists was assessed in vitro, showing that neither BIIL 284 nor WEB 2086 prevented the inflammatory response to IL-8, C5a and zymosan-activated plasma stimulation. However, these agonists elicited LTB4 biosynthesis in isolated rabbit PMNs. Similarly, a cardioprotective effect of PAF and LTB4 receptor antagonists was shown following myocardial I/R in mice. Taken together, these results underscore the intricate involvement of LTB4 and PAF in each other's responses and provide further evidence that targeting both LTs and PAF receptors provides a much stronger anti-inflammatory effect, regulating PMN migration and oedema formation.
Assuntos
Leucotrienos/metabolismo , Fator de Ativação de Plaquetas/metabolismo , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Amidinas/farmacologia , Animais , Azepinas/farmacologia , Bioensaio , Carbamatos/farmacologia , Derme/patologia , Modelos Animais de Doenças , Extravasamento de Materiais Terapêuticos e Diagnósticos/metabolismo , Extravasamento de Materiais Terapêuticos e Diagnósticos/patologia , Extremidades/irrigação sanguínea , Extremidades/patologia , Inflamação/patologia , Leucotrieno B4/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Isquemia Miocárdica/metabolismo , Isquemia Miocárdica/patologia , Infiltração de Neutrófilos/efeitos dos fármacos , Glicoproteínas da Membrana de Plaquetas/agonistas , Glicoproteínas da Membrana de Plaquetas/metabolismo , Propionatos/farmacologia , Quinolinas/farmacologia , Coelhos , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Leucotrienos/agonistas , Receptores de Leucotrienos/metabolismo , Triazóis/farmacologiaRESUMO
OBJECTIVE: The pathogenesis of atherosclerosis is associated with the early retention of low-density lipoproteins that are trapped in the extracellular matrix of the arterial intima by interaction with glycosaminoglycan side chains of proteoglycans. Mutant mouse/human chimeric antibodies of the murine monoclonal antibody P3, which react with N-glycolyl-containing gangliosides and sulfated glycosaminoglycans, were tested for their potentially antiatherogenic properties through the induction of an idiotypic antibody network that may specifically interfere with the binding of low-density lipoproteins to proteoglycan side chains, low-density lipoprotein modification, and foam cell formation. METHODS AND RESULTS: Apolipoprotein E-deficient mice fed a high-fat, high-cholesterol diet received 5 to 6 doses of chP3R99 or chP3S98 mutant antibodies, showing high and low reactivity, respectively, against their respective antigens. Both chimeric antibodies elicited an immunodominant anti-idiotypic response in the absence of adjuvant. A striking (40%-43%) reduction (P<0.01) in total lesion areas was observed in 18-week-old mice immunized with chP3R99, but not chP3S98, compared with PBS-treated mice. The antiatherosclerotic effect was associated with increased mice sera reactivity against heparin and sulfated glycosaminoglycans, including chondroitin and dermatan sulfate. In addition, purified IgG from chP3R99-immunized mice blocked the retention of apolipoprotein B-containing lipoproteins within the arterial wall of apolipoprotein E(-/-) mice. CONCLUSIONS: The present study supports use of active immunization and the mounting of an idiotypic antibody network response against glycosaminoglycans as a novel approach to target atherosclerosis.
Assuntos
Anticorpos Anti-Idiotípicos/uso terapêutico , Apolipoproteínas E/deficiência , Aterosclerose/prevenção & controle , Glicosaminoglicanos/imunologia , Glicosaminoglicanos/metabolismo , Sulfatos/metabolismo , Animais , Anticorpos Anti-Idiotípicos/imunologia , Apolipoproteínas E/genética , Apolipoproteínas E/metabolismo , Artérias/metabolismo , Aterosclerose/etiologia , Aterosclerose/metabolismo , Colesterol na Dieta/efeitos adversos , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Humanos , Lipoproteínas LDL/metabolismo , Masculino , Camundongos , Camundongos Knockout , Proteínas Mutantes Quiméricas/imunologia , Proteínas Mutantes Quiméricas/uso terapêuticoRESUMO
Neutrophils, the most abundant leukocytes in human circulation, are key effectors and regulators of both innate and adaptive immunity which migrate from the bloodstream to sites of inflammation or infection in response to different stimuli. A growing body of evidence has revealed that dysregulated neutrophil activity contributes to the development of several diseases. Targeting their function has been proposed as a potential strategy to treat or mitigate the progression of these disorders. Additionally, neutrophil tropism has been proposed as a strategy to drive therapeutic agents towards targeted disease sites. In this article, we review the proposed nanomedicine approaches to target neutrophils and their components, the regulation of their function and the use of their tropism in drug delivery for therapeutic purposes.
Assuntos
Armadilhas Extracelulares , Nanopartículas , Humanos , Neutrófilos , Inflamação , Imunidade AdaptativaRESUMO
Atherosclerosis is a chronic inflammatory disease of the arterial walls that develops at predisposed sites. As a major risk factor for adverse cardiovascular pathology, atherosclerosis can progress to myocardial infarction and stroke, due to the rupture of unstable atherosclerotic lesions. Macrophage uptake of modified lipoproteins and metabolic dysfunction contributes significantly to the initiation and development of atherosclerotic lesions. The cluster of differentiation 36 receptor [CD36 (SR-B2)] plays a key role in atherosclerotic lesion progression and acts as an efferocytic molecule in the resolution of advanced plaque. In previous studies, linear azapeptide CD36 ligands were shown to exhibit anti-atherosclerotic properties. In the present study, a novel potent and selective macrocyclic azapeptide CD36 ligand, MPE-298, has proven effective in protecting against atherosclerosis progression. Features of greater plaque stability were observed after 8 weeks of daily injections with the cyclic azapeptide in apolipoprotein E-deficient mice fed a high-fat high-cholesterol diet.
RESUMO
Polymer nanoparticles (NPs) are extensively studied as drug delivery systems for various therapeutic indications, including drug and imaging agent delivery to the brain. Despite intensive research, their toxicological profile has yet to be fully characterized. In particular, the more subtle effects of nanomaterials on inflammatory processes have scarcely been investigated. Surface properties of NPs are amongst parameters governing interactions between living cells and NPs. They could considerably influence the toxicity and inflammatory response of the cells exposed to NPs. Polymeric NPs investigated here present a core-shell structure. The core is constituted of hydrophobic poly(lactic acid) (PLA) block and the surface is composed of a shell of hydrophilic block of polyethylene glycol (PEG). The effect of PEG chain length coating on the expression of genes involved in the inflammation response was investigated in two vascular endothelial cell lines (bEnd.3 and HUVEC) by qPCR. Moreover, ROS generation following NP uptake was evaluated. PEGylated NPs induce a mild and transient activation of inflammatory cytokine and chemokine genes. However, differences in PEG chain length did not show any significant effect on cytokine and chemokine gene expression and PEGylated NPs did not trigger ROS generation. The present results could contribute significantly to a deeper understanding of nanomaterial interactions and toxicity with vascular endothelial cells, guiding scientists in material coating choices.
Assuntos
Células Endoteliais , Nanopartículas , Citocinas , Sistemas de Liberação de Medicamentos , Células Endoteliais/metabolismo , Nanopartículas/química , Tamanho da Partícula , Polietilenoglicóis/química , Polímeros/química , Espécies Reativas de OxigênioRESUMO
Activation of toll-like receptors (TLRs) and polymorphonuclear leukocyte (PMN) accumulation at infection sites are critical events of host defense. The involvement of leukotriene (LT) B(4) and platelet-activating factor (PAF) in TLR ligand-induced activation of inflammatory cell functions is essentially unknown. Using an in vitro model of human PMN migration through human endothelial cell monolayers, we demonstrate that prototypic ligands of TLR1/2, 2/6, 3, 4, 5, and 7/8 promote PMN migration, an effect markedly inhibited by 3 LTB(4) receptor antagonists (70-80% inhibition at 100 nM compared to vehicle-treated cells), 3 PAF receptor antagonists (20-50% inhibition at 10 nM), 3 LT biosynthesis inhibitors (75-85% inhibition at 100 nM), and 1 cytosolic phospholipase A(2)alpha (cPLA(2)alpha) inhibitor (90% inhibition at 1 microM). Accordingly, selected TLR ligands caused Ser-505-phosphorylation of cPLA(2)alpha and measurable LTB(4) and PAF biosynthesis in the transmigration assay. As negative controls, interleukin-8- and formyl-methionyl-leucyl-phenylalanine-elicited migration in vitro was not inhibited either by an LTB(4) receptor antagonist or by the cPLA(2)alpha inhibitor. Finally, LTB(4) and PAF receptor antagonists inhibited (up to approximately 65% at optimal doses) TLR ligand-induced PMN infiltration in the mouse air-pouch model. These studies unravel the critical involvement of de novo LTB(4) and PAF biosynthesis in PMN migration elicited by TLR ligands.
Assuntos
Movimento Celular/efeitos dos fármacos , Leucotrieno B4/fisiologia , Neutrófilos/fisiologia , Fator de Ativação de Plaquetas/fisiologia , Receptores Toll-Like/fisiologia , Animais , Azepinas/farmacologia , Di-Hidropiridinas/farmacologia , Feminino , Flagelina/farmacologia , Humanos , Imidazóis/farmacologia , Ligantes , Camundongos , Camundongos Endogâmicos C57BL , Poli I-C/farmacologia , Propionatos/farmacologia , Quinolinas/farmacologia , Tienopiridinas , Receptores Toll-Like/agonistas , Receptores Toll-Like/imunologia , Triazóis/farmacologiaRESUMO
Histoplasma capsulatum (Hc) is a facultative, intracellular parasite of worldwide significance. Infection with Hc produces a broad spectrum of diseases and may progress to a life-threatening systemic disease, particularly in individuals with HIV infection. Resolution of histoplasmosis is associated with the activation of cell-mediated immunity, and leukotriene B(4) plays an important role in this event. Lipid bodies (LBs) are increasingly being recognized as multifunctional organelles with roles in inflammation and infection. In this study, we investigated LB formation in histoplasmosis and its putative function in innate immunity. LB formation in leukocytes harvested from Hc-infected C57BL/6 mice peaks on day 2 postinfection and correlates with enhanced generation of lipid mediators, including leukotriene B(4) and PGE(2). Pretreatment of leukocytes with platelet-activating factor and BLT1 receptor antagonists showed that both lipid mediators are involved in cell signaling for LB formation. Alveolar leukocytes cultured with live or dead Hc also presented an increase in LB numbers. The yeast alkali-insoluble fraction 1, which contains mainly beta-glucan isolated from the Hc cell wall, induced a dose- and time-dependent increase in LB numbers, indicating that beta-glucan plays a signaling role in LB formation. In agreement with this hypothesis, beta-glucan-elicited LB formation was inhibited in leukocytes from 5-LO(-/-), CD18(low) and TLR2(-/-) mice, as well as in leukocytes pretreated with anti-Dectin-1 Ab. Interestingly, human monocytes from HIV-1-infected patients failed to produce LBs after beta-glucan stimulation. These results demonstrate that Hc induces LB formation, an event correlated with eicosanoid production, and suggest a role for these lipid-enriched organelles in host defense during fungal infection.
Assuntos
Antígenos CD18/metabolismo , Infecções por HIV/imunologia , Histoplasmose/imunologia , Proteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Organelas/imunologia , Receptor 2 Toll-Like/metabolismo , beta-Glucanas/imunologia , Adulto , Animais , Antígenos CD18/imunologia , Parede Celular/química , Parede Celular/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , HIV-1 , Histoplasma/imunologia , Humanos , Lectinas Tipo C , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Leucotrieno B4/biossíntese , Leucotrieno B4/imunologia , Lipídeos , Masculino , Proteínas de Membrana/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/imunologia , Organelas/metabolismo , Receptor 2 Toll-Like/imunologiaRESUMO
AIMS: Diabetes is a conventional risk factor for atherosclerotic cardiovascular disease and myocardial infarction (MI) is the most common cause of death among these patients. Mesenchymal stromal cells (MSCs) in patients with type 2 diabetes mellitus (T2DM) and atherosclerosis have impaired ability to suppress activated T-cells (i.e. reduced immunopotency). This is mediated by an inflammatory shift in MSC-secreted soluble factors (i.e. pro-inflammatory secretome) and can contribute to the reduced therapeutic effects of autologous T2DM and atherosclerosis-MSC post-MI. The signalling pathways driving the altered secretome of atherosclerosis- and T2DM-MSC are unknown. Specifically, the effect of IκB kinase ß (IKKß) modulation, a key regulator of inflammatory responses, on the immunopotency of MSCs from T2DM patients with advanced atherosclerosis has not been studied. METHODS AND RESULTS: MSCs were isolated from adipose tissue obtained from patients with (i) atherosclerosis and T2DM (atherosclerosis+T2DM MSCs, n = 17) and (ii) atherosclerosis without T2DM (atherosclerosis MSCs, n = 17). MSCs from atherosclerosis+T2DM individuals displayed an inflammatory senescent phenotype and constitutively expressed active forms of effectors of the canonical IKKß nuclear factor-κB transcription factors inflammatory pathway. Importantly, this constitutive pro-inflammatory IKKß signature resulted in an altered secretome and impaired in vitro immunopotency and in vivo healing capacity in an acute MI model. Notably, treatment with a selective IKKß inhibitor or IKKß knockdown (KD) (clustered regularly interspaced short palindromic repeats/Cas9-mediated IKKß KD) in atherosclerosis+T2DM MSCs reduced the production of pro-inflammatory secretome, increased survival, and rescued their immunopotency both in vitro and in vivo. CONCLUSIONS: Constitutively active IKKß reduces the immunopotency of atherosclerosis+T2DM MSC by changing their secretome composition. Modulation of IKKß in atherosclerosis+T2DM MSCs enhances their myocardial repair ability.
Assuntos
Aterosclerose/enzimologia , Diabetes Mellitus Tipo 2/enzimologia , Quinase I-kappa B/metabolismo , Mediadores da Inflamação/metabolismo , Células-Tronco Mesenquimais/enzimologia , Idoso , Animais , Aterosclerose/genética , Aterosclerose/imunologia , Estudos de Casos e Controles , Proliferação de Células , Células Cultivadas , Senescência Celular , Técnicas de Cocultura , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/imunologia , Modelos Animais de Doenças , Feminino , Humanos , Quinase I-kappa B/antagonistas & inibidores , Quinase I-kappa B/genética , Ativação Linfocitária , Masculino , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/imunologia , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Infarto do Miocárdio/enzimologia , Infarto do Miocárdio/imunologia , Infarto do Miocárdio/cirurgia , Fenótipo , Inibidores de Proteínas Quinases/farmacologia , Secretoma , Transdução de Sinais , Linfócitos T/imunologia , Linfócitos T/metabolismoRESUMO
Growth hormone-releasing peptide-6 (GHRP-6) is part of a group of small synthetic peptides with potent GH-releasing activity that have gained attention in the last two decades by virtue of their cyto- and cardioprotective effects. Despite numerous preclinical studies highlighting the potential cardiovascular benefits of GHRP-6, confirmation of clinical efficacy is still awaited. Recent advances in transdermal drug delivery systems have been made to address challenges related to the poor skin permeation rate of peptides by using pain-free microneedle (MN) devices. Accordingly, highly sensitive and validated analytical methods are required for the potential clinical translation of MN-based peptides. The ultra-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) methods developed in this study aimed to quantify GHRP-6 in biological matrices (plasma, skin) and dissolving polymeric MNs. UHPLC/MS-MS method detection limits of 0.1, 1.1, 0.9 and 1.5 ng/mL were achieved in neat solution, plasma, MN polymer solution, and skin matrices, respectively. Method validation also involved assessment of precision, accuracy, limits of quantification, linearity of matched calibration curves (R2 > 0.990), extraction recovery, matrix effect, stability studies, selectivity, and carry-over effect. Additionally, quality control samples were analyzed at three concentration levels to determine recovery (85-109%) and accuracy/bias (3.2-14.7%). Intra- and inter-day precision were within the range of acceptance (RSDs of 3.0-13.9% and 0.4-14.5%, respectively). The validity and applicability of such methods were successfully demonstrated for transdermal GHRP-6 delivery using GHRP-6-loaded MN patches applied to pig skin.
Assuntos
Oligopeptídeos , Espectrometria de Massas em Tandem , Animais , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Limite de Detecção , Reprodutibilidade dos Testes , SuínosRESUMO
BACKGROUND AND AIMS: Scavenger receptor class B member 3, also known as cluster of differentiation-36 (CD36) receptor, is involved in the uptake and accumulation of modified lipoprotein in macrophages, driving atherosclerosis progression. Azapeptide analogs of growth hormone-releasing peptide-6 (GHRP-6) have been developed as selective CD36 ligands and evaluated for their anti-atherosclerotic properties in apoe-/- mice. METHODS: From 4 to 19 weeks of age, male apoe-/- mice were fed a high fat high cholesterol (HFHC) diet, then switched to normal chow and treated daily with 300 nmol/kg of MPE-001 ([aza-Tyr4]-GHRP-6) or MPE-003 ([aza-(N,N-diallylaminobut-2-ynyl)Gly4]-GHRP-6) for 9 weeks. In another protocol, mice were fed a HFHC diet throughout the study. RESULTS: Azapeptides decreased lesion progression in the aortic arch and reduced aortic sinus lesion areas below pre-existing lesions levels in apoe-/- mice which were switched to chow diet. In mice fed a HFHC throughout the study, azapeptides reduced lesion progression in the aortic vessel and sinus. The anti-atherosclerotic effect of azapeptides was associated with a reduced ratio of iNOS+/CD206+ macrophages within lesions, and lowered plasma inflammatory cytokine levels. Monocytes from azapeptide-treated mice showed altered mitochondrial oxygen consumption rates, consistent with an M2-like phenotype. These effects were dependent on CD36, and not observed in apoe-/-cd36-/- mice. CONCLUSIONS: Azapeptides MPE-001 and MPE-003 diminished aortic lesion progression and reduced, below pre-existing levels, lesions in the aortic sinus of atherosclerotic mice. A relative increase of M2-like macrophages was observed in lesions, associated with reduced systemic inflammation. Development of CD36-selective azapeptide ligands merits consideration for treating atherosclerotic disease.
Assuntos
Apolipoproteínas E , Aterosclerose , Animais , Apolipoproteínas E/genética , Apolipoproteínas E/metabolismo , Aterosclerose/tratamento farmacológico , Aterosclerose/genética , Aterosclerose/prevenção & controle , Antígenos CD36 , Modelos Animais de Doenças , Ligantes , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Oligopeptídeos/farmacologiaRESUMO
Over 1 million cases of scorpion stings are estimated every year, whereas current treatment is limited to antivenom serum combined with supportive therapy. Tityus serrulatus scorpion venom (TsV) is composed of diverse molecules, including toxins that induce a catecholamine storm and mediate classical symptoms of scorpion envenomation. However, the same toxins promote an intense inflammatory response coordinated by innate immune cells, such as macrophages, contributing significantly to the lung edema and mortality caused by TsV injection. Macrophages sense TsV via innate immune receptors, including TLR2, TLR4, and CD14 that promote inflammation and mortality via PGE2/cAMP/PKA/NF-κB/IL-1ß axis. The scavenger receptor CD36 also recognizes TsV, but in contrast to the other receptors, it drives the production of leukotriene B4 (LTB4). This lipid mediator operates via BLT1 receptor to reduce cAMP production and consequently IL-1ß release, which results in resistance to fatal outcomes of experimental scorpion envenomation. EP80317 is an hexapeptide that serves as a ligand for CD36 and features protective effects under conditions such as atherosclerosis and vascular inflammation. In this study, we evaluated the effects of EP80317 treatment during experimental scorpion envenomation. EP80317 treatment suppressed mouse peritoneal macrophage production of IL-1ß, IL-6, tumor necrosis factor (TNF-α), CCL3, and PGE2 in vitro. EP80317 treatment also boosted the production of LTB4 and IL-10 in response to TsV. Importantly, EP80317 restrained lung inflammation and mortality caused by TsV in vivo. Taken together, these data indicate a strong therapeutic potential of EP80317 as a supportive treatment to control inflammation induced by scorpion envenomation.
RESUMO
In subretinal inflammation, activated mononuclear phagocytes (MP) play a key role in the progression of retinopathies. Little is known about the mechanism involved in the loss of photoreceptors leading to vision impairment. Studying retinal damage induced by photo-oxidative stress, we observed that cluster of differentiation 36 (CD36)-deficient mice featured less subretinal MP accumulation and attenuated photoreceptor degeneration. Moreover, treatment with a CD36-selective azapeptide ligand (MPE-001) reduced subretinal activated MP accumulation in wild type mice and preserved photoreceptor layers and function as assessed by electroretinography in a CD36-dependent manner. The azapeptide modulated the transcriptome of subretinal activated MP by reducing pro-inflammatory markers. In isolated MP, MPE-001 induced dissociation of the CD36-Toll-like receptor 2 (TLR2) oligomeric complex, decreasing nuclear factor-kappa B (NF-κB) and NLR family pyrin domain containing 3 (NLRP3) inflammasome activation. In addition, MPE-001 caused an aerobic metabolic shift in activated MP, involving peroxisome proliferator-activated receptor-γ (PPAR-γ) activation, which in turn mitigated inflammation. Accordingly, PPAR-γ inhibition blocked the cytoprotective effect of MPE-001 on photoreceptor apoptosis elicited by activated MP. By altering activated MP metabolism, MPE-001 decreased immune responses to alleviate subsequent inflammation-dependent neuronal injury characteristic of various vision-threatening retinal disorders.
Assuntos
Antígenos CD36/metabolismo , Metabolismo Energético/efeitos dos fármacos , Imunomodulação/efeitos dos fármacos , Retinite/etiologia , Retinite/metabolismo , Animais , Biomarcadores , Citocinas/metabolismo , Suscetibilidade a Doenças , Inflamassomos/metabolismo , Mediadores da Inflamação/metabolismo , Ligantes , Metaboloma , Metabolômica/métodos , Camundongos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Células Fotorreceptoras de Vertebrados/metabolismo , Células Fotorreceptoras de Vertebrados/patologia , Ligação Proteica , Retinite/patologia , Transdução de Sinais/efeitos dos fármacos , Receptor 2 Toll-Like/metabolismoRESUMO
A critical role for leukotriene B(4) (LTB(4)) and/or platelet-activating factor (PAF) in regulating polymorphonuclear cell (PMN) trafficking to inflammatory sites has been reported in a number of experimental inflammatory models. In vitro, newly synthesized LTB(4) and PAF were shown to act in an autocrine/paracrine or intracrine fashion to enhance intracellular arachidonic acid availability and leukotriene biosynthesis. This suggested potentially cooperative effects of these lipid mediators in regulating PMN extravasation. The present study aimed to elucidate whether endogenous LTB(4) and PAF may both act to regulate plasma extravasation and PMN trafficking to inflammatory sites in experimental inflammation. With this aim, we have used selective and potent PAF and LTB(4) receptor antagonist pretreatments in dermal and pulmonary inflammation models in rats. Our results show additive inhibitory effects of dual LTB(4) and PAF receptor blockade in either PAF- or LTB(4)-elicited cutaneous PMN accumulation compared to single-drug administration. Furthermore, the combined administration of the drugs inhibited the PMN accumulation induced by the chemically unrelated soluble agonists tumour necrosis factor-alpha and C5a. Finally, in a model of pulmonary inflammation induced by the intravenous injection of Sephadex beads, lung neutrophilia was reduced by 63% following the administration of LTB(4) and PAF antagonists, in contrast with the lack of effect of single drug administration. Our results strongly support a role of both endogenous LTB(4) and PAF in regulating PMN trafficking to inflammatory sites in various experimental conditions.
Assuntos
Dermatite/imunologia , Leucotrieno B4/imunologia , Infiltração de Neutrófilos/imunologia , Fator de Ativação de Plaquetas/imunologia , Animais , Benzopiranos/farmacologia , Ácidos Carboxílicos/farmacologia , Di-Hidropiridinas/farmacologia , Imidazóis/farmacologia , Masculino , Neutrófilos/imunologia , Glicoproteínas da Membrana de Plaquetas/antagonistas & inibidores , Glicoproteínas da Membrana de Plaquetas/imunologia , Pneumonia/imunologia , Ratos , Ratos Sprague-Dawley , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Receptores Acoplados a Proteínas G/imunologia , Receptores do Leucotrieno B4/antagonistas & inibidores , Receptores do Leucotrieno B4/imunologia , Pele/imunologia , Tiazóis/farmacologiaRESUMO
Unacylated ghrelin (UAG), the most abundant form of ghrelin in circulation, has been shown to exert cardioprotective effect in experimental cardiopathies. The present study aimed to investigate the cardioprotective effect of a linear bioactive fragment of UAG against myocardial ischemia-induced injury and dysfunction in C57BL/6 wild type mice and the mechanisms involved. Treatments were administered at doses of 100 (UAG), 1,000 and 3,000 (UAG6-13) nmol/kg at 12 h interval during 14 days prior to 30 min left coronary artery ligation and reperfusion for a period of 6 or 48 h. The infarct area was decreased in a dose-dependent manner at 48 h of reperfusion, with a reduction of 54% at the highest dose of UAG6-13 tested. Myocardial hemodynamics were improved as demonstrated by an increase in cardiac output, maximum first derivative of left ventricular pressure, and preload recruitable stroke work, a load-independent contractility index. Six hours after reperfusion, circulating levels of IL-6 and TNF-α pro-inflammatory cytokines were reduced, and the effect was maintained at 48 h for TNF-α. 5' AMP-activated protein kinase (AMPK) was activated, while acetyl-CoA carboxylase (ACC) activity was inhibited, along with a decrease in apoptotic protein levels. In isolated hearts, the effect of UAG6-13 was unaffected by the presence of D-Lys3-GHRP-6, a ghrelin receptor (GHSR1a) antagonist, suggesting that the peptide acted through a GHSR1a-independent pathway. The results support the therapeutic application of UAG bioactive peptide fragments against myocardial ischemia/reperfusion injury.
RESUMO
OBJECTIVE: To assess the effect of short-term treatment with GH on left ventricular contractility and remodeling, after the development of heart failure in cardiomyopathic hamsters (CMH). DESIGN: Two groups of 200-day-old UM-X7.1 CMH received daily subcutaneous injections of recombinant bovine (rb) GH (1mg/kg/day) or 0.9% NaCl for 40 days. Golden Syrian hamsters (GSH) were used as controls. At 240-day-old, the hamsters were randomly subjected to (i) assessment of left ventricular systolic function in a Langendorff perfused mode followed by the determination of the passive diastolic pressure-volume relationship and morphometric measurements; (ii) assessment of left ventricular mRNA expression of genes belonging to the fetal gene program including atrial (ANP) and brain (BNP) natriuretic peptides and cardiac myosin heavy chain isoforms and of the circulating levels of the natriuretic peptides. RESULTS: Hearts from CMH were hypertrophied and dilated (p<0.05) compared to hearts from GSH, along with a approximately 10-fold increase in the circulating ANP and BNP levels. Left ventricular BNP and ANP mRNAs were elevated by 2- and 3-fold, respectively, compared to GSH. rbGH reduced both ANP mRNA and ANP circulating levels by 34% (p<0.01) but did not significantly modulate BNP levels. This effect was associated with a preserved systolic function and reverse remodeling as assessed by a leftward shift of the passive diastolic pressure-volume relationship indicating reduced ventricular dilatation. CONCLUSIONS: The data show that a short-term administration of GH in the terminal phase of the disease confers cardioprotection by attenuating systolic dysfunction and by inducing beneficial reverse remodeling.