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1.
Science ; 367(6482): 1140-1146, 2020 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-32139545

RESUMO

Ribosome profiling has revealed pervasive but largely uncharacterized translation outside of canonical coding sequences (CDSs). In this work, we exploit a systematic CRISPR-based screening strategy to identify hundreds of noncanonical CDSs that are essential for cellular growth and whose disruption elicits specific, robust transcriptomic and phenotypic changes in human cells. Functional characterization of the encoded microproteins reveals distinct cellular localizations, specific protein binding partners, and hundreds of microproteins that are presented by the human leukocyte antigen system. We find multiple microproteins encoded in upstream open reading frames, which form stable complexes with the main, canonical protein encoded on the same messenger RNA, thereby revealing the use of functional bicistronic operons in mammals. Together, our results point to a family of functional human microproteins that play critical and diverse cellular roles.


Assuntos
Fases de Leitura Aberta , Peptídeos/genética , Biossíntese de Proteínas/genética , RNA Mensageiro , Sistemas CRISPR-Cas , Humanos , Óperon , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ribossomos/metabolismo , Transcriptoma
2.
Chem Biol Interact ; 318: 108971, 2020 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-32017913

RESUMO

Pulpal infection is one of the most common causes of dental emergency admission. Tooth pain due to infection caused by gram-negative bacteria is the main manifestation of this sort of dental problem. The GPR173 signaling pathway is a highly conserved G-protein-coupled receptor that mediates neurological and reproductive function. In this study, we found that GPR173 was fairly expressed in isolated human dental pulp cells, and its expression was reduced in response to pro-inflammatory lipopolysaccharide (LPS) treatment. The activation of GPR173 by its ligand Phoenixin-20 reduced LPS-induced cytotoxicity, as revealed by a reduction in the release of LDH. Additionally, Phoenixin-20 suppressed LPS-induced release of pro-inflammatory cytokines and inflammatory mediators, including IL-6, MCP-1, VCAM-1, and ICAM-1, as well as MMP-2 and MMP-9. Mechanistically, we showed the suppressive action of Phoenixin-20 on LPS-induced activation of TLR-4 and Myd88 as well as the activation of the NF-κB pathway. Collectively, our study demonstrates that the GPR173 signaling pathway is an important mediator of LPS-induced inflammation, and the activation of GPR173 by its natural ligand Phoenixin-20 exhibits robust anti-inflammatory effects in dental pulp cells, suggesting that GPR173 is an interesting target molecule in the development of pulp cell-based therapies.


Assuntos
Polpa Dentária/citologia , Inflamação/induzido quimicamente , Lipopolissacarídeos/toxicidade , Peptídeos/farmacologia , Células Cultivadas , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Inflamação/metabolismo , Inflamação/prevenção & controle , Receptores Acoplados a Proteínas-G/genética , Receptores Acoplados a Proteínas-G/metabolismo
3.
J Agric Food Chem ; 68(8): 2381-2392, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32037817

RESUMO

Increasing level of inflammation and oxidative stress could lead to memory impairment. The purpose of this study was to determine the neuroprotective effects of walnut peptides against memory deficits induced by lipopolysaccharide (LPS) in mice and further to explore the underlying anti-inflammatory mechanisms against LPS-elicited inflammation in BV-2 cells. Results showed that walnut protein hydrolysate (WPH) and its low-molecular-weight fraction (WPHL) could ameliorate the memory deficits induced by LPS via normalizing the inflammatory response and oxidative stress in brain, especially WPHL. Furthermore, 18 peptides with anti-inflammatory activities on LPS-activated BV-2 cells were identified from WPHL and it was found that Trp, Gly, and Leu residues in peptides might contribute to the anti-inflammation. Meanwhile, the strong anti-inflammatory effects of LPF, GVYY, and APTLW might be related to their hydrophobic and aromatic amino acid residues as well. LPF, GVYY, and APTLW could reduce the content of proinflammatory mediators and cytokines by downregulating related enzyme expressions and mRNA expressions. Additionally, ROS and mitochondria homeostasis might also contribute to their anti-inflammatory effects.


Assuntos
Anti-Inflamatórios/administração & dosagem , Disfunção Cognitiva/tratamento farmacológico , Juglans/química , Estresse Oxidativo/efeitos dos fármacos , Peptídeos/administração & dosagem , Animais , Anti-Inflamatórios/química , Disfunção Cognitiva/induzido quimicamente , Disfunção Cognitiva/imunologia , Disfunção Cognitiva/psicologia , Humanos , Lipopolissacarídeos/efeitos adversos , Aprendizagem em Labirinto , Camundongos , Peso Molecular , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/química , Nozes/química , Peptídeos/química
4.
J Phys Chem Lett ; 11(5): 1662-1667, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-32058725

RESUMO

Phospholipid scramblases that catalyze lipid transbilayer movement are associated with intercellular signaling and lipid homeostasis. Although several studies have shown that the hydrophilic residue-rich groove of the proteins mediates lipid scrambling, the interactions between the groove and the lipid bilayers remain poorly understood. Here we have revealed the structural features of model transmembrane peptides that conduct lipid scrambling as well as the interactions between the peptides and the surrounding lipids by means of experimental and simulation techniques. Peptides with two strongly hydrophilic residues located on the same side of the helices and at a deeper position in the membrane exhibited high scramblase activities. All-atom molecular dynamics simulations showed that the interactions between the hydrophilic residues and lipid head groups regulate the membrane thinning and disorder near the peptides in an order that correlates with the scramblase activity of the peptides. These results provide a basis for understanding the lipid scrambling mechanisms by transmembrane regions.


Assuntos
Peptídeos/metabolismo , Fosfolipídeos/metabolismo , Sequência de Aminoácidos , Interações Hidrofóbicas e Hidrofílicas , Simulação de Dinâmica Molecular , Peptídeos/química , Fosfolipídeos/química , Lipossomas Unilamelares/química , Lipossomas Unilamelares/metabolismo
5.
Artigo em Inglês | MEDLINE | ID: mdl-32062367

RESUMO

Protein-arginine methyltransferases catalyze the methylation of the guanidine (NG) group of proteinic L-arginine (Arg) to produce monomethyl and dimethylarginine proteins. Their proteolysis releases the free amino acids monomethylarginine (MMA), symmetric dimethylarginine (SDMA) and asymmetric dimethylarginine (ADMA), respectively. MMA, SDMA and ADMA are inhibitors of the nitric oxide synthase (NOS) activity. High circulating and low urinary concentrations of ADMA and SDMA are considered risk factors in the cardiovascular and renal systems, mainly due to their inhibitory action on NOS activity. Identity, biological activity and concentration of NG-methylated proteins are largely unknown. The present study addressed these issues by using GC-MS and LC-MS/MS approaches. GC-MS was used to quantify free ADMA released by classical HCl-catalyzed hydrolysis of three synthetic Arg-vasopressin (V) peptides and of unknown endogenous NG-dimethylated proteins. The cyclic (c) disulfide forms of Arg-vasopressin analogs, i.e., Arg-vasopressin (cV-Arg-Gly-NH2), asymmetrically NG-dimethylated vasopressin (cV-ADMA-Gly-NH2) and symmetrically NG-dimethylated vasopressin (cV-SDMA-Gly-NH2) were used as model peptides in quantitative GC-MS analyses of ADMA, SDMA and other expected amino acids from the hydrolyzed Arg-vasopressin analogs. cV-ADMA-Gly-NH2 and cV-SDMA-Gly-NH2 were discriminated from cV-Arg-Gly-NH2 by LC-MS and LC-MS/MS, yet they were indistinguishable from each other. The same applies to the respective open (o) reduced and di-S-acetamide forms of oV-ADMA-Gly-NH2, oV-SDMA-Gly-NH2 and oV-Arg-Gly-NH2. Our LC-MS and LC-MS/MS studies suggest that the Arg-vasopressin analogs form [(M-H)]+ and [(M-H)+H]+ in the positive ESI mode and undergo in part conversion of their terminal Gly-NH2 (NH2, 16 Da) group to Gly-OH (OH, 17 Da). The product ion mass spectra of the di-S-acetamide forms are complex and contain several intense mass fragments differing by 1 Da. cV-ADMA-Gly-NH2 and cV-SDMA-Gly-NH2 induced platelet aggregation in platelet-rich human plasma with moderately different initial velocity and maximal aggregation rates compared to cV-Arg-Gly-NH2. Previous studies showed that human red blood cells are rich in large (>50 kDa) ADMA-containing proteins of unknown identity. Our LC-MS/MS proteomic study identified several membrane and cytosolic erythrocytic NG-dimethylated proteins, including spectrin-α (280 kDa), spectrin-ß (247 kDa) and protein 4.1 (80 kDa). Being responsible for the stability of the erythrocyte membrane, the newly identified main targets for NG-dimethylation in human erythrocytes should be given a closer look in erythrocytic diseases like hereditary spherocytosis.


Assuntos
Arginina Vasopressina , Cromatografia Líquida/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Guanidina/química , Espectrometria de Massas em Tandem/métodos , Arginina/análogos & derivados , Arginina/análise , Arginina/sangue , Arginina/química , Arginina Vasopressina/análise , Arginina Vasopressina/sangue , Arginina Vasopressina/química , Proteínas Sanguíneas/análise , Proteínas Sanguíneas/química , Humanos , Modelos Lineares , Masculino , Peptídeos/análise , Peptídeos/sangue , Peptídeos/química , Projetos Piloto , Processamento de Proteína Pós-Traducional
6.
Chem Biol Interact ; 319: 109007, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32087110

RESUMO

Acetylcholinesterase (AChE) terminates cholinergic neurotransmission by hydrolyzing acetylcholine. The collagen-tailed AChE tetramer is a product of 2 genes, ACHE and ColQ. The AChE tetramer consists of 4 identical AChE subunits and one polyproline-rich peptide, whose function is to hold the 4 AChE subunits together. Our goal was to determine the amino acid sequence of the polyproline-rich peptide(s) in Torpedo californica AChE (TcAChE) tetramers to aid in the analysis of images that will be acquired by cryo-EM. Collagen-tailed AChE was solubilized from Torpedo californica electric organ, converted to 300 kDa tetramers by digestion with trypsin, and purified by affinity chromatography. Polyproline-rich peptides were released by denaturing the TcAChE tetramers in a boiling water bath, and reducing disulfide bonds with dithiothreitol. Carbamidomethylated peptides were separated from TcAChE protein on a spin filter before they were analyzed by liquid chromatography tandem mass spectrometry on a high resolution Orbitrap Fusion Lumos mass spectrometer. Of the 64 identified collagen-tail (ColQ) peptides, 60 were from the polyproline-rich region near the N-terminus of ColQ. The most abundant proline-rich peptides were SVNKCCLLTPPPPPMFPPPFFTETNILQE, at 40% of total mass-spectral signal intensity, and SVNKCCLLTPPPPPMFPPPFFTETNILQEVDLNNLPLEIKPTEPSCK, at 27% of total intensity. The high abundance of these 2 peptides makes them candidates for the principal form of the polyproline-rich peptide in the trypsin-treated TcAChE tetramers.


Assuntos
Acetilcolinesterase/metabolismo , Peptídeos/metabolismo , Torpedo/metabolismo , Sequência de Aminoácidos , Animais , Colágeno/metabolismo
7.
Medicine (Baltimore) ; 99(8): e18912, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32080074

RESUMO

BACKGROUND: Knee osteoarthritis (KOA) is the most common form of degenerative arthritis. We used Phellinus linteus (PL), which has been well-known anti-inflammatory function. In this study, we will evaluate if PL extract improves symptoms with KOA. METHODS: This study will be an 8-week single-center randomized controlled double-blind clinical trial. Total of 24 subjects with KOA will be enrolled and they will be divided into 3 groups, PL 1,000 mg, PL 1,500 mg and placebo. Subjects will be followed up every 4 weeks with efficacy and safety at the 2nd and 3rd visits. All subjects should maintain a dosage schedule for this protocol. The primary outcome will be assessed with the Korean version of the Western Ontario and McMasters Universities. And the secondary outcomes will be measured using the visual analog scale, quality of life scale (EQ-5D-3L), ESR, C-reactive protein, and C-telopeptide of type-II collagen. Statistical analysis will be performed on the principle of full analysis set. DISCUSSION: This study has inclusion and exclusion criteria and a well-controlled intervention. This clinical trial is the first step to assess the efficacy and safety of PL in patients with KOA. This study will make an important contribution to the literature and aid follow-up research into the use of PL in KOA.


Assuntos
Cartilagem Articular/efeitos dos fármacos , Articulação do Joelho/efeitos dos fármacos , Osteoartrite do Joelho/tratamento farmacológico , Extratos Vegetais/administração & dosagem , Administração Oral , Adulto , Idoso , Sedimentação Sanguínea/efeitos dos fármacos , Proteína C-Reativa/efeitos dos fármacos , Colágeno Tipo I/efeitos dos fármacos , Humanos , Pessoa de Meia-Idade , Osteoartrite do Joelho/sangue , Osteoartrite do Joelho/patologia , Peptídeos/efeitos dos fármacos , Placebos/administração & dosagem , Extratos Vegetais/uso terapêutico , Estudos Prospectivos , Qualidade de Vida , República da Coreia/epidemiologia , Resultado do Tratamento
8.
Lancet ; 395(10227): 878-887, 2020 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-32087818

RESUMO

BACKGROUND: Nerinetide, an eicosapeptide that interferes with post-synaptic density protein 95, is a neuroprotectant that is effective in preclinical stroke models of ischaemia-reperfusion. In this trial, we assessed the efficacy and safety of nerinetide in human ischaemia-reperfusion that occurs with rapid endovascular thrombectomy in patients who had an acute ischaemic stroke. METHODS: For this multicentre, double-blind, randomised, placebo-controlled study done in 48 acute care hospitals in eight countries, we enrolled patients with acute ischaemic stroke due to large vessel occlusion within a 12 h treatment window. Eligible patients were aged 18 years or older with a disabling ischaemic stroke at the time of randomisation, had been functioning independently in the community before the stroke, had an Alberta Stroke Program Early CT Score (ASPECTS) greater than 4, and vascular imaging showing moderate-to-good collateral filling, as determined by multiphase CT angiography. Patients were randomly assigned (1:1) to receive intravenous nerinetide in a single dose of 2·6 mg/kg, up to a maximum dose of 270 mg, on the basis of estimated or actual weight (if known) or saline placebo by use of a real-time, dynamic, internet-based, stratified randomised minimisation procedure. Patients were stratified by intravenous alteplase treatment and declared endovascular device choice. All trial personnel and patients were masked to sequence and treatment allocation. All patients underwent endovascular thrombectomy and received alteplase in usual care when indicated. The primary outcome was a favourable functional outcome 90 days after randomisation, defined as a modified Rankin Scale (mRS) score of 0-2. Secondary outcomes were measures of neurological disability, functional independence in activities of daily living, excellent functional outcome (mRS 0-1), and mortality. The analysis was done in the intention-to-treat population and adjusted for age, sex, baseline National Institutes of Health Stroke Scale score, ASPECTS, occlusion location, site, alteplase use, and declared first device. The safety population included all patients who received any amount of study drug. This trial is registered with ClinicalTrials.gov, NCT02930018. FINDINGS: Between March 1, 2017, and Aug 12, 2019, 1105 patients were randomly assigned to receive nerinetide (n=549) or placebo (n=556). 337 (61·4%) of 549 patients with nerinetide and 329 (59·2%) of 556 with placebo achieved an mRS score of 0-2 at 90 days (adjusted risk ratio 1·04, 95% CI 0·96-1·14; p=0·35). Secondary outcomes were similar between groups. We observed evidence of treatment effect modification resulting in inhibition of treatment effect in patients receiving alteplase. Serious adverse events occurred equally between groups. INTERPRETATION: Nerinetide did not improve the proportion of patients achieving good clinical outcomes after endovascular thrombectomy compared with patients receiving placebo. FUNDING: Canadian Institutes for Health Research, Alberta Innovates, and NoNO.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Peptídeos/uso terapêutico , Acidente Vascular Cerebral/tratamento farmacológico , Trombectomia , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Isquemia Encefálica/complicações , Proteína 4 Homóloga a Disks-Large/efeitos dos fármacos , Método Duplo-Cego , Procedimentos Endovasculares , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fármacos Neuroprotetores/efeitos adversos , Peptídeos/efeitos adversos , Acidente Vascular Cerebral/etiologia , Resultado do Tratamento
9.
J Agric Food Chem ; 68(10): 3132-3139, 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32064873

RESUMO

Thrombin is currently one of the important targets for the treatment and prevention of thrombosis. At present, there are few reports on the application of lactoferrin peptides in anticoagulation. In this study, a peptide with the amino acid sequence of LRPVAAEIY (LF-LR) derived from lactoferrin was shown to possess antithrombotic activity. LF-LR (5 mM) significantly prolonged activated partial thromboplastin time, prothrombin time, and thrombin time for 13.4, 1.7, and 5.1 s, respectively. It prolonged the coagulation time of fibrinogen from 15.3 ± 0.4 to 20.2 ± 0.5 s by affecting the conformation of thrombin. Using circular dichroism analysis, LF-LR can increase the α-helix content of thrombin from 25.6 to 56.7% and made the ß-sheet disappear. In addition, LF-LR also quenched fluorescence of thrombin at about 346 nm (λEx = 280 nm). By means of molecular docking, it was found that LF-LR could bind to both the active site and the exosite-I of thrombin, and the combined LYS60F, TRP60D, ASP189, LYS36, and ARG77A are typical amino acids in the two domains, respectively.


Assuntos
Anticoagulantes/química , Lactoferrina/química , Peptídeos/química , Trombina/química , Sequência de Aminoácidos , Animais , Sítios de Ligação , Domínio Catalítico , Bovinos , Fibrinogênio/química , Humanos , Cinética , Simulação de Acoplamento Molecular , Ligação Proteica , Tempo de Trombina
10.
Chem Commun (Camb) ; 56(16): 2507-2510, 2020 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-32003763

RESUMO

Radiolabeling of peptides with fluorine-18 is hurdled by their chemical sensitivity and complicated processes. Original triflyl-pyridine intermediates afforded ammonium precursors that were radiolabeled at low temperature. From that study, a generic tag has been designed to allow a simple one-step/late-stage radiolabelling of peptides. The strategy has been transposed to an automated "on-resin" radiolabelling.


Assuntos
Peptídeos/síntese química , Compostos Radiofarmacêuticos/síntese química , Resinas Sintéticas/síntese química , Radioisótopos de Flúor , Halogenação , Estrutura Molecular , Peptídeos/química , Compostos Radiofarmacêuticos/química , Resinas Sintéticas/química , Temperatura Ambiente
11.
Chem Commun (Camb) ; 56(18): 2767-2770, 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32022009

RESUMO

We synthesized "glyco-arylopeptides", whose folding structure significantly changes depending on the kind of saccharide in their side chain. The saccharide moiety interacts with the main chain via hydrogen bonding, and the non-natural polypeptides form two well-defined architectures-(P)-31- and (M)-41-helices-depending on the length of the saccharide chains and even the configuration of a single stereo-genic center in the epimers.


Assuntos
Glicopeptídeos/química , Oligossacarídeos/química , Peptídeos/síntese química , Teoria da Densidade Funcional , Estrutura Molecular , Peptídeos/química , Dobramento de Proteína
12.
Chem Commun (Camb) ; 56(20): 3015-3018, 2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-32048648

RESUMO

The uncapped tripeptide DPhe-Phe-Leu acts as self-assembly template to yield supramolecular hydrogel biomaterials. As an example, self-assembling DPhe-Phe-Leu-Asp-Val contains the LDV bioadhesive motif for ß1 integrin activation. Hydrogels made of the two peptides successfully mimic fibronectin of the extracellular matrix and lead to high cell viability, adhesion, and spreading.


Assuntos
Hidrogéis/química , Imagem Óptica , Peptídeos/química , Adesão Celular , Sobrevivência Celular , Fibroblastos/química , Humanos , Substâncias Macromoleculares/química , Conformação Molecular , Tamanho da Partícula , Propriedades de Superfície
13.
Chem Commun (Camb) ; 56(13): 1926-1935, 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32009137

RESUMO

Nature encodes the information required for life in two fundamental biopolymers: nucleic acids and proteins. Peptide nucleic acid (PNA), a synthetic analog comprised of nucleobases arrayed along a pseudopeptide backbone, has the ability to combine the power of nucleic acids to encode information with the versatility of amino acids to encode structure and function. Historically, PNA has been perceived as a simple nucleic acid mimic having desirable properties such as high biostability and strong affinity for complementary nucleic acids. In this feature article, we aim to adjust this perception by highlighting the ability of PNA to act as a peptide mimic and showing the largely untapped potential to encode information in the amino acid sequence. First, we provide an introduction to PNA and discuss the use of conjugation to impart tunable properties to the biopolymer. Next, we describe the integration of functional groups directly into the PNA backbone to impart specific physical properties. Lastly, we highlight the use of these integrated amino acid side chains to encode peptide-like sequences in the PNA backbone, imparting novel activity and function and demonstrating the ability of PNA to simultaneously mimic both a peptide and a nucleic acid.


Assuntos
Ácidos Nucleicos Peptídicos/química , Interações Hidrofóbicas e Hidrofílicas , Hibridização de Ácido Nucleico , Peptídeos/química
14.
Chem Commun (Camb) ; 56(10): 1573-1576, 2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-31930273

RESUMO

Generation of short peptides with a single ß-strand structure in solution is difficult. Herein, we design a new class of single ß-strand peptidic mimics that are stable without self-aggregation in protic and non-protic solvents. Introduction of one present ß-strand mimic can induce and propagate the ß-strand structure for at least a penta-peptide sequence.


Assuntos
Peptídeos/química , Ligações de Hidrogênio , Espectroscopia de Ressonância Magnética , Simulação de Dinâmica Molecular , Conformação Proteica em Folha beta , Temperatura Ambiente
15.
J Agric Food Chem ; 68(6): 1621-1633, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-31967468

RESUMO

Collagen peptides can promote wound healing and are closely related to microbiome colonization. We investigated the relationship among collagen peptides, wound healing, and wound microflora colonization by administering the murine wound model with Salmo salar skin collagen peptides (Ss-SCPs) and Tilapia nilotica skin collagen peptides (Tn-SCPs). We analyzed the vascular endothelial growth factor (VEGF), fibroblast growth factors (ß-FGF), pattern recognition receptor (NOD2), antimicrobial peptides (ß-defence14, BD14), proinflammatory (TNF-α, IL-6, and IL-8) and anti-inflammatory (IL-10) cytokines, macrophages, neutrophil infiltration levels, and microbial communities in the rat wound. The healing rates of the Ss-SCP- and Tn-SCP-treated groups were significantly accelerated, associated with decreased TNF-α, IL-6, and IL-8 and upregulated BD14, NOD2, IL-10, VEGF, and ß-FGF. Accelerated healing in the collagen peptide group shows that the wound microflora such as Leuconostoc, Enterococcus, and Bacillus have a positive effect on wound healing (P < 0.01). Other microbiome species such as Stenotrophomonas, Bradyrhizobium, Sphingomonas, and Phyllobacterium had a negative influence and decreased colonization (P < 0.01). Altogether, these studies show that collagen peptide could upregulate wound NOD2 and BD14, which were implicated in microflora colonization regulation in the wound tissue and promoted wound healing by controlling the inflammatory reaction and increasing wound angiogenesis and collagen deposition.


Assuntos
Colágeno/química , Proteínas de Peixes/química , Microbiota/efeitos dos fármacos , Proteína Adaptadora de Sinalização NOD2/genética , Peptídeos/administração & dosagem , Pele/química , Ferimentos e Lesões/fisiopatologia , beta-Defensinas/genética , Administração Cutânea , Animais , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/isolamento & purificação , Ciclídeos , Fatores de Crescimento de Fibroblastos/genética , Fatores de Crescimento de Fibroblastos/imunologia , Humanos , Interleucina-10/genética , Interleucina-10/imunologia , Masculino , Camundongos , Proteína Adaptadora de Sinalização NOD2/imunologia , Peptídeos/química , Ratos , Ratos Sprague-Dawley , Salmo salar , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/imunologia , Cicatrização/efeitos dos fármacos , Ferimentos e Lesões/tratamento farmacológico , Ferimentos e Lesões/imunologia , Ferimentos e Lesões/microbiologia , beta-Defensinas/imunologia
16.
Exp Parasitol ; 210: 107830, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31917970

RESUMO

Chagas disease, also known as American trypanosomiasis, is a potentially life-threatening illness caused by the protozoan parasite Trypanosoma cruzi, which is transmitted by insects of the family Reduviidae. Since conventional treatments with nitroheterocyclic drugs show serious adverse reactions and have questionable efficiency, different research groups have investigated polypeptide-based approaches to interfere with the parasite cell cycle in other Trypanosomatids. These strategies are supported by the fact that surface players are candidates to develop surface ligands that impair function since they may act as virulence factors. In this study, we used a phage display approach to identify peptides from one library-LX8CX8 (17 aa) (where X corresponds to any amino acid). After testing different biopanning conditions using live or fixed epimastigotes, 10 clones were sequenced that encoded the same peptide, named here as EPI18. The bacteriophage expressing EPI18 binds to epimastigotes from distinct strains of T. cruzi. To confirm these results, this peptide was synthetized, biotinylated, and assayed using flow cytometry and confocal microscopy analyses. These assays confirmed the specificity of the binding capacity of EPI18 toward epimastigote surfaces. Our findings suggest that EPI18 may have potential biotechnological applications that include peptide-based strategies to control parasite transmission.


Assuntos
Doença de Chagas/tratamento farmacológico , Peptídeos/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Sequência de Aminoácidos , Bacteriófagos/isolamento & purificação , Bioprospecção , Biotinilação , Doença de Chagas/parasitologia , Doença de Chagas/prevenção & controle , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Humanos , Microscopia Confocal , Microscopia de Fluorescência , Biblioteca de Peptídeos , Peptídeos/química , Peptídeos/isolamento & purificação , Peptídeos/metabolismo , Temperatura Ambiente , Trypanosoma cruzi/genética
17.
J Phys Chem Lett ; 11(4): 1282-1290, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-31977221

RESUMO

Recent chiral sum-frequency generation vibrational spectroscopy (SFG-VS) measurements revealed that two N-H stretching modes in the 3100-3500 cm-1 range in folded peptide LK7ß exhibit chiral characteristics. Here, we report the first phase-resolved subwavenumber high-resolution broadband SFG-VS (HR-BB-SFG-VS) measurement of the folded peptide LK7ß. The results show that this chiral N-H band consists of four, instead of two, distinctive peaks, and they are with two groups of opposite spectral phases. Moreover, the phases of these N-H peaks completely flip from the l-LK7ß to the d-LK7ß peptide, suggesting that the chirality of the N-H in the folded peptide LK7ß is completely governed by the chirality of the Cα-H of the amino acids. This discovery provides a clue on why proteins in nature are composed of the α-amino acids rather than ß- or γ-amino acids and may help us understand how life works.


Assuntos
Hidrogênio/química , Nitrogênio/química , Peptídeos/química , Sequência de Aminoácidos , Carbono/química , Dobramento de Proteína , Espectrofotometria Infravermelho , Estereoisomerismo
18.
J Phys Chem Lett ; 11(4): 1215-1221, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-31978303

RESUMO

Site-selective dissociation induced by core photoexcitation of biomolecules is of key importance for the understanding of radiation damage processes and dynamics and for its promising use as "chemical scissors" in various applications. However, identifying products of site-selective dissociation in large molecules is challenging at the carbon, nitrogen, and oxygen edges because of the high recurrence of these atoms and related chemical groups. In this paper, we present the observation of site-selective dissociation at the sulfur L-edge in the gas-phase peptide methionine enkephalin, which contains only a single sulfur atom. Near-edge X-ray absorption mass spectrometry has revealed that the resonant S 2p → σ*C-S excitation of the sulfur contained in the methionine side chain leads to site-selective dissociation, which is not the case after core ionization above the sulfur L-edge. The prospects of such results for the study of charge dynamics in biomolecular systems are discussed.


Assuntos
Gases/química , Peptídeos/química , Enxofre/química , Espectroscopia por Absorção de Raios X , Encefalinas/química , Metionina/química , Prótons , Teoria Quântica
19.
J Agric Food Chem ; 68(8): 2393-2405, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-31995979

RESUMO

Hyperglycemia-induced oxidative stress can cause liver damage in diabetes, and protein hydrolysates with antidiabetic and antioxidant properties are emerging as a potential therapy. In this study, protective effects of casein hydrolysates against live oxidative damage in streptozotocin/high-fat-induced diabetic rats were studied and potentially bioactive peptides were explored by an integrated approach of differential peptide and in silico analysis. Results showed that different casein hydrolysates significantly alleviated liver oxidative damage (p < 0.05) via different mechanisms. Particularly, casein hydrolyzed by a papain-flavourzyme combination (P-FCH) treatment significantly improved liver antioxidant enzyme activities by enhancing nuclear factor erythroid 2-related factor 2 (Nrf2) transcription (p < 0.05). Furthermore, 18 peptides were screened as potential bioactive peptides by analyzing differential peptides among different hydrolysates combined with in silico prediction. Among them, the dipeptide WM might directly inhibit the Kelch-like ECH-associated protein 1 (Keap1)-Nrf2 interaction as potential Nrf2 activators. These results suggested that P-FCH might be an alternative way to treat liver damage in diabetes.


Assuntos
Caseínas/química , Diabetes Mellitus Experimental/tratamento farmacológico , Hepatopatias/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Peptídeos/administração & dosagem , Animais , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/metabolismo , Dieta Hiperlipídica/efeitos adversos , Feminino , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Hepatopatias/genética , Hepatopatias/metabolismo , Masculino , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Peptídeos/química , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo
20.
Pharm Res ; 37(2): 30, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31915939

RESUMO

PURPOSE: mRNA has recently emerged as a potent therapeutics and requires safe and effective delivery carriers, particularly prone to address its issues of poor stability and escape from endosomes. In this context, we designed poly(D,L-lactide) (PLA)-based micelles with N-succinimidyl (NS) ester decorated hydrophilic hairy corona to trap/couple a cationic fusogenic peptide and further complex mRNA. METHODS: Two strategies were investigated, namely (i) sequential immobilization of peptide and mRNA onto the micelles (layer-by-layer, LbL) or (ii) direct immobilization of peptide-mRNA pre-complex (PC) on the micelles. After characterization by means of size, surface charge, peptide/mRNA coupling/complexation and mRNA serum stability, carrier cytotoxicity and transfection capacity were evaluated with dendritic cells (DCs) using both GFP and luciferase mRNAs. RESULTS: Whatever the approach used, the micellar assemblies afforded full protection of mRNA in serum while the peptide-mRNA complex yielded complete mRNA degradation. In addition, the micellar assemblies allowed to significantly reduce the toxicity observed with the peptide-mRNA complex. They successfully transfected hard-to transfect DCs, with a superior efficiency for the LbL made ones (whatever mRNAs studied) showing the impact of the elaboration process on the carrier properties. CONCLUSIONS: These results show the relevance and potential of this new PLA/peptide based micelle platform to improve mRNA stability and delivery, while offering the possibility of further multifunctionality through PLA core encapsulation.


Assuntos
Portadores de Fármacos/química , Peptídeos/química , Poliésteres/química , Povidona/análogos & derivados , RNA Mensageiro/química , Animais , Linhagem Celular , Sobrevivência Celular , Estabilidade de Medicamentos , Expressão Gênica , Interações Hidrofóbicas e Hidrofílicas , Camundongos , Micelas , Povidona/química , RNA Mensageiro/genética , Transfecção
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