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1.
J Food Sci ; 86(7): 2898-2909, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34146412

RESUMO

The antioxidant peptides extracted from plants or animals have shown great potential in preventing food quality deterioration caused by oxidization. Here, peptide fractions obtained from hairtail surimi hydrolysates (HSH) were investigated for structure and color-protective effect. The results showed the <3 kDa fraction obtained from HSH by ultrafiltration could be separated into five major fractions (A-E) by gel chromatography, among which fraction A possessed the highest antioxidant activities. This fraction A could be further separated into two fractions (A1 and A2 ) by the reversed-phase high-performance liquid chromatography, and fraction A2 with lower α-helix content exhibited the higher antioxidant activities. The amino acids sequence of fraction A2 was identified as DLYANTVLSGGTTMYPGIADR (2214.0627 Da). The synthetic peptide with this sequence was also found to exhibit obvious antioxidant activity. Moreover, both HSH, fractions A1 and A2 , and synthetic peptide demonstrated color-protective effects during the beef preservation. Taken together, the results obtained showed that the natural antioxidant peptides could be isolated from HSH, which can be used in meat preservation for inhibiting color deterioration. PRACTICAL APPLICATION: This study demonstrated the potential of hairtail surimi hydrolysates (HSH) as a source of antioxidant peptides. Furthermore, these antioxidant peptides purified from HSH exhibited the potential for prevention of beef color deterioration of beef, providing a potential application for meat preservation. Particularly, using the antioxidant peptides sourced from fish surimi for meat preservation may not only ease the safety concerns about artificial preservatives but also create a unique selling proposition, especially in far eastern Asian countries, since consumers in these countries believe "umami" is the combination of "fish" and "meat."


Assuntos
Antioxidantes/farmacologia , Produtos Pesqueiros/análise , Peixes/metabolismo , Conservação de Alimentos/métodos , Carne/análise , Fragmentos de Peptídeos/farmacologia , Hidrolisados de Proteína/farmacologia , Animais , Antioxidantes/química , Bovinos , Oxirredução , Fragmentos de Peptídeos/química , Hidrolisados de Proteína/química
2.
J Food Sci ; 86(7): 3046-3060, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34146413

RESUMO

This study aimed to assess the biological properties of peptide fractions isolated from dried fermented dairy products (jameed) as influenced by processing. Peptide fractions were separated by reversed-phase high-performance liquid chromatography (RP-HPLC) from salted (Sa) and unsalted (Us) cow milk jameed after drying the fermented curd by sun drying (Sd) or freeze-drying (Fd) and were characterized for their antioxidant capacity and inhibitory activity toward angiotensin I-converting enzyme (ACE) and α-amylase. Sd samples showed more numerous peptide peaks in RP-HPLC chromatograms than Fd samples, regardless of the salt content. High antioxidant activity was evidenced in several peptide fractions from FdUs jameed (including fractions 1, 2, 4, 7, 8, 9, and 10), SdUs jameed (1, 2, 5, 7, and 9), and FdSa jameed (2, 5, 6, and 9). By contrast, peptide fractions from SdSa (1, 2, 3, 5, 8, and 9), SdUs (4, 5, and 10), and FdUs (5, 6, and 8) jameed displayed the highest ACE inhibitory activity. Similarly, the highest inhibition of α-amylase was obtained with fractions from SdSa (1, 2, 3, 4, 5, 6, 8, and 9), SdUs (2 and 6), and FdUs (1, 7 and 9) jameed. A significant negative correlation was evidenced between antioxidant activity and anti-α-amylase activity of peptide fractions from SdSa jameed. These findings demonstrate that cow milk jameed is a source of bioactive peptides with antioxidant, anti-ACE, and anti-α-amylase properties in vitro, which can be tailored by adjusting the salt content and the drying conditions. PRACTICAL APPLICATION: This study shows that cow milk jameed, a staple fermented food in several Mediterranean countries, can serve as a useful source of multifunctional bioactive peptides with potential antioxidant, hypotensive, and hypoglycemic effects, which may help prevent and manage chronic health conditions such as hypertension, type 2 diabetes, and the metabolic syndrome. The bioactivities of certain peptide fractions were enhanced by lowering the salt content of jameed or by the drying method. The relatively simple RP-HPLC method described in this study can be used to isolate the peptide fractions of interest for further characterization and use as functional ingredients.


Assuntos
Aminoácidos/análise , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Anti-Hipertensivos/farmacocinética , Antioxidantes/farmacologia , Produtos Fermentados do Leite , Hipoglicemiantes/farmacologia , Leite/química , Fragmentos de Peptídeos/farmacologia , Inibidores da Enzima Conversora de Angiotensina/química , Animais , Anti-Hipertensivos/química , Antioxidantes/química , Bovinos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipertensão/tratamento farmacológico , Hipoglicemiantes/química , Fragmentos de Peptídeos/química , Peptidil Dipeptidase A/metabolismo
3.
Int J Mol Sci ; 22(10)2021 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-34068392

RESUMO

Myocardial infarction (MI) remains the leading cause of death in the western world. Despite advancements in interventional revascularization technologies, many patients are not candidates for them due to comorbidities or lack of local resources. Non-invasive approaches to accelerate revascularization within ischemic tissues through angiogenesis by providing Vascular Endothelial Growth Factor (VEGF) in protein or gene form has been effective in animal models but not in humans likely due to its short half-life and systemic toxicity. Here, we tested the hypothesis that PR1P, a small VEGF binding peptide that we developed, which stabilizes and upregulates endogenous VEGF, could be used to improve outcome from MI in rodents. To test this hypothesis, we induced MI in mice and rats via left coronary artery ligation and then treated animals with every other day intraperitoneal PR1P or scrambled peptide for 14 days. Hemodynamic monitoring and echocardiography in mice and echocardiography in rats at 14 days showed PR1P significantly improved multiple functional markers of heart function, including stroke volume and cardiac output. Furthermore, molecular biology and histological analyses of tissue samples showed that systemic PR1P targeted, stabilized and upregulated endogenous VEGF within ischemic myocardium. We conclude that PR1P is a potential non-invasive candidate therapeutic for MI.


Assuntos
Antígeno AC133/metabolismo , Modelos Animais de Doenças , Isquemia/complicações , Infarto do Miocárdio/prevenção & controle , Neovascularização Fisiológica/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Feminino , Isquemia/metabolismo , Isquemia/patologia , Camundongos , Camundongos Endogâmicos C57BL , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Fator A de Crescimento do Endotélio Vascular/genética , Função Ventricular Esquerda/efeitos dos fármacos
4.
Molecules ; 26(11)2021 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-34072901

RESUMO

The areca (Areca catechu L.) nut kernel (ANK) is a good potential protein source for its high protein content of 9.89-14.62 g/100 g and a high yield of around 300,000 tons per year in China. However, utilization of the areca nut kernel is limited. To expand the usage of ANK in pharmaceutical or foods industries, areca nut kernel globulin was extracted and angiotensin-I converting enzyme (ACE) inhibition peptides were prepared and identified using gel chromatography, reversed phase HPLC separation, UPLC-ESI-MS/MS analysis and in silico screening. Finally, a novel ACE-inhibitory heptapeptide (Ala-Pro-Lys-Ile-Glu-Glu-Val) was identified and chemically synthesized. The combination pattern between APKIEEV and ACE, and the inhibition kinetics, antihypertensive effect and endothlein-1 inhibition activity of APKIEEV were studied. The results of the molecular docking demonstrated that APKIEEV could bind to four active sites (not the key active sites) of ACE via short hydrogen bonds and demonstrated high ACE-inhibitory activity (IC50: 550.41 µmol/L). Moreover, APKIEEV exhibited a significantly lowering effect on both the systolic blood pressure and diastolic blood pressure of spontaneously hypertensive rats, and had considerable suppression ability on intracellular endothelin-1. These results highlight the potential usage of APKIEEV as ingredients of antihypertensive drugs or functional foods.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/química , Areca/metabolismo , Globulinas/farmacologia , Sequência de Aminoácidos/genética , Animais , Anti-Hipertensivos/química , Pressão Sanguínea/efeitos dos fármacos , Globulinas/metabolismo , Hipertensão/metabolismo , Masculino , Simulação de Acoplamento Molecular/métodos , Nozes/metabolismo , Fragmentos de Peptídeos/farmacologia , Peptídeos/química , Peptidil Dipeptidase A/metabolismo , Hidrolisados de Proteína/química , Hidrolisados de Proteína/metabolismo , Ratos , Ratos Endogâmicos SHR , Espectrometria de Massas em Tandem/métodos
5.
Int J Mol Sci ; 22(10)2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-34065004

RESUMO

Phosphinate pseudopeptide are analogs of peptides containing phosphinate moiety in a place of the amide bond. Due to this, the organophosphorus fragment resembles the tetrahedral transition state of the amide bond hydrolysis. Additionally, it is also capable of coordinating metal ions, for example, zinc or magnesium ions. These two properties of phosphinate pseudopeptides make them an ideal candidate for metal-related protease inhibitors. This research investigates the influence of additional residue in the P2 position on the inhibitory properties of phosphinopeptides. The synthetic strategy is proposed, based on retrosynthetic analysis. The N-C-P bond formation in the desired compounds is conveniently available from the three-component condensation of appropriate amino components, aldehydes, and hypophosphorous acid. One of the crucial synthetic steps is the careful selection of the protecting groups for all the functionals. Determination of the inhibitor activity of the obtained compounds has been done using UV-Vis spectroscopy and standard substrate L-Leu-p-nitroanilide toward the enzymes isolated from the porcine kidney (SsLAP, Sus scrofa Leucine aminopeptidase) and barley seeds (HvLAP, Hordeum vulgare Leucine aminopeptidase). An efficient procedure for the preparation of phosphinotripeptides has been performed. Activity test shown that introduction of additional residue into P2 position obtains the micromolar range inhibitors of SsLAP and HvLAP. Moreover, careful selection of the residue in the P2 position should improve its selectivity toward mammalian and plant leucyl aminopeptidases.


Assuntos
Inibidores Enzimáticos/farmacologia , Leucil Aminopeptidase/antagonistas & inibidores , Fragmentos de Peptídeos/farmacologia , Fosfinas/química , Animais , Inibidores Enzimáticos/química , Modelos Moleculares , Fragmentos de Peptídeos/química , Conformação Proteica , Suínos
6.
Int J Mol Sci ; 22(10)2021 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-34069596

RESUMO

Acinetobacter baumannii is a serious nosocomial pathogen with multiple drug resistance (MDR), the control of which has become challenging due to the currently used antibiotics. Our main objective in this study is to determine the antibacterial and antibiofilm activities of the antimicrobial peptide, Octominin, against MDR A. baumannii and derive its possible modes of actions. Octominin showed significant bactericidal effects at a low minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) of 5 and 10 µg/mL, respectively. Time-kill kinetic analysis and bacterial viability tests revealed that Octominin showed a concentration-dependent antibacterial activity. Field-emission scanning electron microscopy (FE-SEM) analysis revealed that Octominin treatment altered the morphology and membrane structure of A. baumannii. Propidium iodide (PI) and reactive oxygen species (ROS) generation assays showed that Octominin increased the membrane permeability and ROS generation in A. baumannii, thereby causing bacterial cell death. Further, a lipopolysaccharides (LPS) binding assay showed an Octominin concentration-dependent LPS neutralization ability. Biofilm formation inhibition and eradication assays further revealed that Octominin inhibited biofilm formation and showed a high biofilm eradication activity against A. baumannii. Furthermore, up to a concentration of 100 µg/mL, Octominin caused no hemolysis and cell viability changes in mammalian cells. An in vivo study in zebrafish showed that the Octominin-treated group had a significantly higher relative percentage survival (54.1%) than the untreated group (16.6%). Additionally, a reduced bacterial load and fewer alterations in histological analysis confirmed the successful control of A. baumannii by Octominin in vivo. Collectively, these data suggest that Octominin exhibits significant antibacterial and antibiofilm activities against the multidrug-resistant A. baumannii, and this AMP can be developed further as a potent AMP for the control of antibiotic resistance.


Assuntos
Acinetobacter baumannii/efeitos dos fármacos , Peptídeos Catiônicos Antimicrobianos/farmacologia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/metabolismo , Animais , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Peptídeos Catiônicos Antimicrobianos/metabolismo , Biofilmes/efeitos dos fármacos , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Sinergismo Farmacológico , Cinética , Viabilidade Microbiana/efeitos dos fármacos , Modelos Animais , Fragmentos de Peptídeos/metabolismo , Peixe-Zebra
7.
Nat Commun ; 12(1): 3185, 2021 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-34045461

RESUMO

Systemic inflammation as manifested in sepsis is an excessive, life-threatening inflammatory response to severe bacterial or viral infection or extensive injury. It is also a thrombo-inflammatory condition associated with vascular leakage/hemorrhage and thrombosis that is not effectively treated by current anti-inflammatory or anti-thrombotic drugs. Here, we show that MB2mP6 peptide nanoparticles, targeting the Gα13-mediated integrin "outside-in" signaling in leukocytes and platelets, inhibited both inflammation and thrombosis without causing hemorrhage/vascular leakage. MB2mP6 improved mouse survival when infused immediately or hours after onset of severe sepsis. Furthermore, platelet Gα13 knockout inhibited septic thrombosis whereas leukocyte Gα13 knockout diminished septic inflammation, each moderately improving survival. Dual platelet/leukocyte Gα13 knockout inhibited septic thrombosis and inflammation, further improving survival similar to MB2mP6. These results demonstrate that inflammation and thrombosis independently contribute to poor outcomes and exacerbate each other in systemic inflammation, and reveal a concept of dual anti-inflammatory/anti-thrombotic therapy without exacerbating vascular leakage.


Assuntos
Antígenos CD18/antagonistas & inibidores , Subunidades alfa G12-G13 de Proteínas de Ligação ao GTP/antagonistas & inibidores , Fragmentos de Peptídeos/farmacologia , Sepse/tratamento farmacológico , Trombose/tratamento farmacológico , Animais , Anti-Inflamatórios , Plaquetas/efeitos dos fármacos , Plaquetas/imunologia , Plaquetas/metabolismo , Antígenos CD18/metabolismo , Cloretos/administração & dosagem , Cloretos/toxicidade , Modelos Animais de Doenças , Compostos Férricos/administração & dosagem , Compostos Férricos/toxicidade , Fibrinolíticos , Subunidades alfa G12-G13 de Proteínas de Ligação ao GTP/metabolismo , Humanos , Leucócitos/efeitos dos fármacos , Leucócitos/imunologia , Leucócitos/metabolismo , Macrófagos , Camundongos , Camundongos Knockout , Nanopartículas/uso terapêutico , Fragmentos de Peptídeos/uso terapêutico , Adesividade Plaquetária/efeitos dos fármacos , Agregação Plaquetária/efeitos dos fármacos , Cultura Primária de Células , Ligação Proteica/efeitos dos fármacos , Sepse/sangue , Sepse/complicações , Sepse/imunologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , Células THP-1 , Trombose/sangue , Trombose/induzido quimicamente
8.
J Med Chem ; 64(10): 6856-6876, 2021 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-33973470

RESUMO

Butyrylcholinesterase (BChE) has been considered as a potential therapeutic target for Alzheimer's disease (AD) because of its compensation capacity to hydrolyze acetylcholine (ACh) and its close association with Aß deposit. Here, we identified S06-1011 (hBChE IC50 = 16 nM) and S06-1031 (hBChE IC50 = 25 nM) as highly effective and selective BChE inhibitors, which were proved to be safe and long-acting. Candidate compounds exhibited neuroprotective effects and the ability to improve cognition in scopolamine- and Aß1-42 peptide-induced cognitive deficit models. The best candidate S06-1011 increased the level of ghrelin, a substrate of BChE, which can function as improving the mental mood appetite. The weight gain of the S06-1011-treated group remarkably increased. Hence, BChE inhibition not only plays a protective role against dementia but also exerts a great effect on treating and nursing care.


Assuntos
Butirilcolinesterase/química , Inibidores da Colinesterase/química , Fármacos Neuroprotetores/química , Peptídeos beta-Amiloides/farmacologia , Animais , Sítios de Ligação , Butirilcolinesterase/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Inibidores da Colinesterase/metabolismo , Inibidores da Colinesterase/farmacologia , Inibidores da Colinesterase/uso terapêutico , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/patologia , Modelos Animais de Doenças , Desenho de Fármacos , Grelina/metabolismo , Meia-Vida , Humanos , Camundongos , Camundongos Endogâmicos ICR , Simulação de Dinâmica Molecular , Fármacos Neuroprotetores/metabolismo , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Fragmentos de Peptídeos/farmacologia , Quinolinas/química , Quinolinas/metabolismo , Quinolinas/farmacologia , Quinolinas/uso terapêutico , Ratos Sprague-Dawley , Relação Estrutura-Atividade , Regulação para Cima/efeitos dos fármacos
9.
Methods Mol Biol ; 2256: 157-177, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34014522

RESUMO

Over the past decades, peptide-based drugs have gained increasing interest in a wide range of treatment applications, primarily because of high potency and selectivity, as well as good efficacy, tolerability, and safety often achieved with peptides. Attempts to target postsynaptic density protein of 95 (PSD-95) PSD-95/Discs large/Zonula occludens-1 (PDZ) domains, which mediate the formation of a ternary complex with the N-methyl-D-aspartate (NMDA) receptor and neuronal nitric oxide synthase (nNOS) responsible for excitotoxicity in ischemic stroke, by high-affinity small molecules have failed in the past. In this chapter, we focus on the discovery of peptide-based drugs targeting PSD-95, using AVLX-144 as an example, from the synthesis, over binding assays to its target, to further in vitro experiments based on the development of AVLX-144, a potential stroke treatment, which is planned to enter clinical trials in 2020.


Assuntos
Proliferação de Células , Córtex Cerebral/citologia , Proteína 4 Homóloga a Disks-Large/antagonistas & inibidores , Neurônios/citologia , Domínios PDZ , Fragmentos de Peptídeos/farmacologia , Animais , Células Cultivadas , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/efeitos dos fármacos , Neurônios/metabolismo
10.
J Food Sci ; 86(6): 2457-2467, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34056723

RESUMO

Hydrolysates containing angiotensin I-converting enzyme (ACE)-inhibitory peptide were prepared from protein of Alaska pollack skins using alcalase and trypsin. The protein hydrolysate was separated by ultrafiltration, Sephadex G-25 gel filtration chromatography and reversed phase high-performance liquid chromatography (HPLC), from which a novel purified peptide was obtained. Both random coil structure and ß-sheet in the purified peptide were revealed in Fourier transform infrared spectrum. The amino sequence of the purified peptide was identified as GPLGVP, VLYPVK, VFLENVLR, and FEEF by HPLC-Q-TOF-MS (HPLC-quadrupole time-of-flight mass spectrometry). The peptide GPLGVP whose molecular weight was 538.31 Da showed the highest ACE inhibitory activity (IC50  = 105.8 µM). The purified peptide featured a noncompetitive inhibition kinetic mechanism was shown in the Lineweaver-Burk plots and was susceptible to enzymes as indicated in the studies on stability of gastrointestinal proteases. Moreover, the peptide GPLGVP can combine ACE catalytic pocket through hydrogen bonds and other forces with high binding power as disclosed in molecular docking simulation, which provides the inhibitory effect of GPLGVP on ACE.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/isolamento & purificação , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Fragmentos de Peptídeos/isolamento & purificação , Fragmentos de Peptídeos/farmacologia , Peptidil Dipeptidase A/química , Pele/química , Alaska , Animais , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Gadiformes , Hidrólise , Simulação de Acoplamento Molecular , Hidrolisados de Proteína/química
11.
Emerg Microbes Infect ; 10(1): 810-821, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33847245

RESUMO

EK1 peptide is a membrane fusion inhibitor with broad-spectrum activity against human coronaviruses (CoVs). In the outbreak of COVID-19, we generated a lipopeptide EK1V1 by modifying EK1 with cholesterol, which exhibited significantly improved antiviral activity. In this study, we surprisingly found that EK1V1 also displayed potent cross-inhibitory activities against divergent HIV-1, HIV-2, and simian immunodeficiency virus (SIV) isolates. Consistently, the recently reported EK1 derivative EK1C4 and SARS-CoV-2 derived fusion inhibitor lipopeptides (IPB02 ∼ IPB09) also inhibited HIV-1 Env-mediated cell-cell fusion and infection efficiently. In the inhibition of a panel of HIV-1 mutants resistant to HIV-1 fusion inhibitors, EK1V1 and IPB02-based inhibitors exhibited significantly decreased or increased activities, suggesting the heptad repeat-1 region (HR1) of HIV-1 gp41 being their target. Furthermore, the sequence alignment and molecular docking analyses verified the target site and revealed the mechanism underlying the resistance. Combined, we conclude that this serendipitous discovery provides a proof-of-concept for a common mechanism of viral fusion and critical information for the development of broad-spectrum antivirals.


Assuntos
Antivirais/farmacologia , Coronavirus/efeitos dos fármacos , HIV-1/efeitos dos fármacos , HIV-2/efeitos dos fármacos , Vírus da Imunodeficiência Símia/efeitos dos fármacos , Internalização do Vírus/efeitos dos fármacos , Sequência de Aminoácidos , Animais , Antivirais/isolamento & purificação , Relação Dose-Resposta a Droga , Inibidores da Fusão de HIV/isolamento & purificação , Inibidores da Fusão de HIV/farmacologia , Humanos , Lipopeptídeos/isolamento & purificação , Lipopeptídeos/farmacologia , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Fragmentos de Peptídeos/isolamento & purificação , Fragmentos de Peptídeos/farmacologia , SARS-CoV-2/efeitos dos fármacos , Relação Estrutura-Atividade , Replicação Viral/efeitos dos fármacos
12.
Emerg Microbes Infect ; 10(1): 810-821, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: covidwho-1180458

RESUMO

EK1 peptide is a membrane fusion inhibitor with broad-spectrum activity against human coronaviruses (CoVs). In the outbreak of COVID-19, we generated a lipopeptide EK1V1 by modifying EK1 with cholesterol, which exhibited significantly improved antiviral activity. In this study, we surprisingly found that EK1V1 also displayed potent cross-inhibitory activities against divergent HIV-1, HIV-2, and simian immunodeficiency virus (SIV) isolates. Consistently, the recently reported EK1 derivative EK1C4 and SARS-CoV-2 derived fusion inhibitor lipopeptides (IPB02 ∼ IPB09) also inhibited HIV-1 Env-mediated cell-cell fusion and infection efficiently. In the inhibition of a panel of HIV-1 mutants resistant to HIV-1 fusion inhibitors, EK1V1 and IPB02-based inhibitors exhibited significantly decreased or increased activities, suggesting the heptad repeat-1 region (HR1) of HIV-1 gp41 being their target. Furthermore, the sequence alignment and molecular docking analyses verified the target site and revealed the mechanism underlying the resistance. Combined, we conclude that this serendipitous discovery provides a proof-of-concept for a common mechanism of viral fusion and critical information for the development of broad-spectrum antivirals.


Assuntos
Antivirais/farmacologia , Coronavirus/efeitos dos fármacos , HIV-1/efeitos dos fármacos , HIV-2/efeitos dos fármacos , Vírus da Imunodeficiência Símia/efeitos dos fármacos , Internalização do Vírus/efeitos dos fármacos , Sequência de Aminoácidos , Animais , Antivirais/isolamento & purificação , Relação Dose-Resposta a Droga , Inibidores da Fusão de HIV/isolamento & purificação , Inibidores da Fusão de HIV/farmacologia , Humanos , Lipopeptídeos/isolamento & purificação , Lipopeptídeos/farmacologia , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Fragmentos de Peptídeos/isolamento & purificação , Fragmentos de Peptídeos/farmacologia , SARS-CoV-2/efeitos dos fármacos , Relação Estrutura-Atividade , Replicação Viral/efeitos dos fármacos
13.
Cell Mol Life Sci ; 78(11): 4973-4992, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33864480

RESUMO

Amyloid beta (Aß) is linked to the pathology of Alzheimer's disease (AD). At physiological concentrations, Aß was proposed to enhance neuroplasticity and memory formation by increasing the neurotransmitter release from presynapse. However, the exact mechanisms underlying this presynaptic effect as well as specific contribution of endogenously occurring Aß isoforms remain unclear. Here, we demonstrate that Aß1-42 and Aß1-16, but not Aß17-42, increased size of the recycling pool of synaptic vesicles (SV). This presynaptic effect was driven by enhancement of endogenous cholinergic signalling via α7 nicotinic acetylcholine receptors, which led to activation of calcineurin, dephosphorylation of synapsin 1 and consequently resulted in reorganization of functional pools of SV increasing their availability for sustained neurotransmission. Our results identify synapsin 1 as a molecular target of Aß and reveal an effect of physiological concentrations of Aß on cholinergic modulation of glutamatergic neurotransmission. These findings provide new mechanistic insights in cholinergic dysfunction observed in AD.


Assuntos
Peptídeos beta-Amiloides/farmacologia , Fragmentos de Peptídeos/farmacologia , Sinapses/metabolismo , Sinapsinas/metabolismo , Vesículas Sinápticas/efeitos dos fármacos , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Animais , Cálcio/metabolismo , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Feminino , Humanos , Camundongos , Camundongos Knockout , Neurônios/citologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurotransmissores/metabolismo , Nicotina/farmacologia , Fosforilação/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Vesículas Sinápticas/fisiologia , Receptor Nicotínico de Acetilcolina alfa7/deficiência , Receptor Nicotínico de Acetilcolina alfa7/genética
14.
FASEB J ; 35(5): e21595, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33908676

RESUMO

Current histological measurement techniques for interstitial collagen, the basis of interstitial fibrosis, are semi-quantitative at best and only provide a ratio of collagen levels within tissues. The Genesis200 imaging system and supplemental image analysis software, FibroIndex from HistoIndex, is a novel, automated platform that uses second-harmonic generation (SHG) for imaging and characterization of interstitial collagen deposition and additional characteristics, in the absence of any staining. However, its ability to quantify renal fibrosis requires investigation. This study compared SHG imaging of renal fibrosis in mice with unilateral ureteric obstruction (UUO), to that of Masson's trichrome staining (MTS) and immunohistochemistry (IHC) of collagen I. Additionally, the platform generated data on collagen morphology and distribution patterns. While all three methods determined that UUO-injured mice underwent significantly increased renal fibrosis after 7 days, the HistoIndex platform additionally determined that UUO-injured mice had a significantly increased collagen-to-tissue cross reticulation ratio (all P < .001 vs sham group). Furthermore, in UUO-injured mice treated with the relaxin family peptide receptor-1 agonists, relaxin (0.5 mg/kg/day) or B7-33 (0.25 mg/kg/day), or angiotensin converting enzyme-inhibitor, perindopril (1 mg/kg/day) over the 7-day period, only the HistoIndex platform determined that the drug-induced prevention of renal fibrosis correlated with significantly reduced collagen fiber thickness and collagen-to-tissue cross reticulation ratio, but increased collagen fiber counts. Relaxin or B7-33 treatment also increased renal matrix metalloproteinase-2 and reduced tissue inhibitor of metalloproteinase-1 levels (all P < .01 vs UUO alone). This study demonstrated the diagnostic value of the HistoIndex platform over currently used staining techniques.


Assuntos
Fibrose/patologia , Nefropatias/patologia , Fragmentos de Peptídeos/farmacologia , Relaxina/farmacologia , Obstrução Ureteral/complicações , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Animais , Fibrose/tratamento farmacológico , Fibrose/etiologia , Nefropatias/tratamento farmacológico , Nefropatias/etiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL
15.
J Cancer Res Clin Oncol ; 147(7): 1927-1934, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33811273

RESUMO

BACKGROUND: Tetraspanin KAI1/CD82, a tumor metastasis suppressor, has emerged as a promising molecular target for the management of metastatic disease. However, the peptide mimicking small extracellular ring domain (EC1) of CD82 has not been fully investigated for the function of inhibiting cell migration in vitro and tumor metastasis in vivo. METHODS: Different cancer cells were treated with EC1 mimic peptide in order to detect migration and invasion by the healing assay and transwell. Cell aggregation and adhesion assays were used to investigate the function of homotypic cell-cell aggregation and adhesion to tissue culture plates. Then, we established syngeneic and xenograft animal models to assess the metastasis inhibitory effect of EC1 mimic peptide in vivo. RESULTS: In vitro studies, the EC1 mimic peptide had been showed to promote homotypic cell-cell aggregation, suppress cell migration, invasion and adherence in multiple tumor cell types. In vivo metastasis assays, the EC1 mimic peptide could strongly inhibit the pulmonary metastasis of LCC in syngeneic mice model and SW620 and H1299 in xenograft mice model. CONCLUSION: This novel finding will improve our understanding of the mechanism by which CD82 inhibits metastasis, and suggests that EC1 mimic peptide may be a promising candidate for developing anti-metastasis drugs.


Assuntos
Movimento Celular , Proteína Kangai-1/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Fragmentos de Peptídeos/farmacologia , Animais , Apoptose , Proliferação de Células , Humanos , Técnicas In Vitro , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Camundongos Nus , Metástase Neoplásica , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Mar Drugs ; 19(4)2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33916201

RESUMO

More than 7000 red algae species have been classified. Although most of them are underused, they are a protein-rich marine resource. The hydrolysates of red algal proteins are good candidates for the inhibition of the angiotensin-I-converting enzyme (ACE). The ACE is one of the key factors for cardiovascular disease, and the inhibition of ACE activity is related to the prevention of high blood pressure. To better understand the relationship between the hydrolysates of red algal proteins and the inhibition of ACE activity, we attempted to identify novel ACE inhibitory peptides from Pyropia pseudolinearis. We prepared water soluble proteins (WSP) containing phycoerythrin, phycocyanin, allophycocyanin, and ribulose 1,5-bisphosphate carboxylase/oxygenase. In vitro analysis showed that the thermolysin hydrolysate of the WSP had high ACE inhibitory activity compared to that of WSP. We then identified 42 peptides in the hydrolysate by high-performance liquid chromatography and mass spectrometry. Among 42 peptides, 23 peptides were found in chloroplast proteins. We then synthesized the uncharacterized peptides ARY, YLR, and LRM and measured the ACE inhibitory activity. LRM showed a low IC50 value (0.15 µmol) compared to ARY and YLR (1.3 and 5.8 µmol). In silico analysis revealed that the LRM sequence was conserved in cpcA from Bangiales and Florideophyceae, indicating that the novel ACE inhibitory peptide LRM was highly conserved in red algae.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/farmacologia , Fragmentos de Peptídeos/farmacologia , Peptidil Dipeptidase A/metabolismo , Proteínas de Plantas/farmacologia , Rodófitas/metabolismo , Inibidores da Enzima Conversora de Angiotensina/síntese química , Inibidores da Enzima Conversora de Angiotensina/isolamento & purificação , Humanos , Hidrólise , Simulação de Acoplamento Molecular , Fragmentos de Peptídeos/síntese química , Fragmentos de Peptídeos/isolamento & purificação , Peptidil Dipeptidase A/química , Proteínas de Plantas/isolamento & purificação , Ligação Proteica , Conformação Proteica , Relação Estrutura-Atividade
17.
Chem Biol Interact ; 342: 109475, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33872574

RESUMO

Endorphins are endogenous opioid neuropeptides that are mainly produced from pituitary gland in response to pain and different triggers including interleukin 1 beta (IL-1ß) and corticotropin-releasing factor (CRF). Angiotensin II (Ang II) can stimulate ß-endorphin production, but the exact molecular mechanisms involved in this effect, and the role of the released ß-endorphin in Ang II-mediated pressor response remain elusive. Male rats were injected with IL-1ß receptor antagonist (IL-1Ra, 100 µg/kg), the CRF receptor blocker, astressin (20 µg/rat) or a combination of both, prior to Ang II injection (200 µg/kg). Another group of rats was given naloxone (1.6 mg/kg) or telmisartan (5 mg/kg) before Ang II injection. Blood pressure and serum and Paraventricular nucleus (PVN) ß-endorphin were detected. Moreover, IL-1ß and CRF as well as markers of oxidative stress [malondialdehyde (MDA) and superoxide dismutase (SOD)], inflammation [C-reactive protein (CRP)] and neuronal activation (c-Fos, l-glutamate, and phosphorylated ERK) were measured in the PVN of different groups. Ang II induced a pressor response and increased serum and PVN ß-endorphin levels that were attenuated in rats pre-treated with astressin or/and IL-1Ra. Moreover, Ang II increased PVN oxidative stress, inflammation and neuronal activation. Telmisartan abolished the previous effects, while naloxone, astressin and IL-1Ra aggravated Ang II-mediated pressor response and most of the biochemical changes. These findings suggest that, Ang II can induce ß-endorphin release via increasing both IL-1ß and CRF levels which in result mitigates Ang II-mediated central responses. This study highlights ß-endorphin as a possible target for treating hypertension.


Assuntos
Angiotensina II/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Núcleo Hipotalâmico Paraventricular/efeitos dos fármacos , beta-Endorfina/metabolismo , Animais , Hormônio Liberador da Corticotropina/metabolismo , Hormônio Liberador da Corticotropina/farmacologia , Proteína Antagonista do Receptor de Interleucina 1/farmacologia , Interleucina-1beta/metabolismo , Masculino , Naloxona/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Núcleo Hipotalâmico Paraventricular/metabolismo , Fragmentos de Peptídeos/farmacologia , Ratos , Telmisartan/farmacologia
18.
Molecules ; 26(5)2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33806637

RESUMO

Marine collagen peptides have high potential in promoting skin wound healing. This study aimed to investigate wound healing activity of collagen peptides derived from Sipunculus nudus (SNCP). The effects of SNCP on promoting healing were studied through a whole cortex wound model in mice. Results showed that SNCP consisted of peptides with a molecular weight less than 5 kDa accounted for 81.95%, rich in Gly and Arg. SNCP possessed outstanding capacity to induce human umbilical vein endothelial cells (HUVEC), human immortalized keratinocytes (HaCaT) and human skin fibroblasts (HSF) cells proliferation and migration in vitro. In vivo, SNCP could markedly improve the healing rate and shorten the scab removal time, possessing a scar-free healing effect. Compared with the negative control group, the expression level of tumor necrosis factor-α, interleukin-1ß and transforming growth factor-ß1 (TGF-ß1) in the SNCP group was significantly down-regulated at 7 days post-wounding (p < 0.01). Moreover, the mRNA level of mothers against decapentaplegic homolog 7 (Smad7) in SNCP group was up-regulated (p < 0.01); in contrast, type II TGF-ß receptors, collagen I and α-smooth muscle actin were significantly down-regulated at 28 days (p < 0.01). These results indicate that SNCP possessed excellent activity of accelerating wound healing and inhibiting scar formation, and its mechanism was closely related to reducing inflammation, improving collagen deposition and recombination and blockade of the TGF-ß/Smads signal pathway. Therefore, SNCP may have promising clinical applications in skin wound repair and scar inhibition.


Assuntos
Cicatriz/tratamento farmacológico , Colágeno/farmacologia , Queratinócitos/efeitos dos fármacos , Fragmentos de Peptídeos/isolamento & purificação , Fragmentos de Peptídeos/farmacologia , Poliquetos/química , Pele/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Animais , Cicatriz/metabolismo , Colágeno/química , Humanos , Queratinócitos/metabolismo , Masculino , Camundongos , Fragmentos de Peptídeos/química , Transdução de Sinais , Pele/metabolismo
19.
Eur J Pharmacol ; 901: 174072, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33823184

RESUMO

Glucagon-like peptide-2 (GLP-2) is secreted from enteroendocrine L-type cells of the gut and also released from preproglucagonergic (PPG) neurons in the nucleus tractus solitarius (NTS) and adjacent medial reticular nucleus of the brain stem. The neurons in the NTS express GLP-2, and the neurons send extensive projections to the hypothalamus. Recent studies show that the intracerebroventricular administration of GLP-2 significantly suppresses food intake in animals and some evidence suggest that the melanocortin receptor-4 (MC4-R) signaling in the hypothalamus is required for intracerebroventricular GLP-2-mediated inhibition of feeding. There is proopiomelanocortin (POMC) positive neurons expressing MC4-R in the NTS. Suppression of MC4-R expressing neurons in the brain stem inhibits gastric emptying. In this study, we tested the effects of NTS GLP-2R activation and blockade on feeding behavior and evaluated the endogenous melanocortin system's role in the NTS in mediating effects of GLP-2 on feeding behavior in fed and fasted rats. Our results demonstrated that microinjection of GLP-2 into the NTS suppressed food intake in fasted-refeeding rats but did not affect food intake in free-feeding rats, and this inhibition was blocked by pretreatment of either Exendin (9-39) or SHU 9119, suggesting the GLP-2 system in the NTS exerts an inhibitory action on food intake. MC4-R mediates this action in the NTS.


Assuntos
Depressores do Apetite/farmacologia , Peptídeo 2 Semelhante ao Glucagon/farmacologia , Receptor Tipo 4 de Melanocortina/efeitos dos fármacos , Núcleo Solitário , Animais , Ingestão de Alimentos/efeitos dos fármacos , Jejum , Peptídeo 2 Semelhante ao Glucagon/administração & dosagem , Peptídeo 2 Semelhante ao Glucagon/antagonistas & inibidores , Masculino , Hormônios Estimuladores de Melanócitos/farmacologia , Microinjeções , Fragmentos de Peptídeos/farmacologia , Ratos , Ratos Sprague-Dawley
20.
Int J Mol Sci ; 22(9)2021 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-33922379

RESUMO

Peptide-based drugs are an attractive class of therapeutic agents, recently recognized by the pharmaceutical industry. These molecules are currently being used in the development of innovative therapies for diverse health conditions, including tropical diseases such as leishmaniasis. Despite its socioeconomic influence on public health, leishmaniasis remains long-neglected and categorized as a poverty-related disease, with limited treatment options. Peptides with antileishmanial effects encountered to date are a structurally heterogeneous group, which can be found in different natural sources-amphibians, reptiles, insects, bacteria, marine organisms, mammals, plants, and others-or inspired by natural toxins or proteins. This review details the biochemical and structural characteristics of over one hundred peptides and their potential use as molecular frameworks for the design of antileishmanial drug leads. Additionally, we detail the main chemical modifications or substitutions of amino acid residues carried out in the peptide sequence, and their implications in the development of antileishmanial candidates for clinical trials. Our bibliographic research highlights that the action of leishmanicidal peptides has been evaluated mainly using in vitro assays, with a special emphasis on the promastigote stage. In light of these findings, and considering the advances in the successful application of peptides in leishmaniasis chemotherapy, possible approaches and future directions are discussed here.


Assuntos
Antiprotozoários/farmacologia , Leishmania/efeitos dos fármacos , Leishmaniose/tratamento farmacológico , Fragmentos de Peptídeos/farmacologia , Animais , Humanos , Leishmaniose/parasitologia
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