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1.
Naunyn Schmiedebergs Arch Pharmacol ; 396(11): 2957-2975, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37097335

RESUMO

Trimetozine is used to be indicated for the treatment of mental illnesses, particularly anxiety. The present study provides data on the pharmacological profile of trimetozine derivative morpholine (3,5-di-tert-butyl-4-hydroxyphenyl) methanone (LQFM289) which was designed from molecular hybridization of trimetozine lead compound and 2,6-di-tert-butyl-hydroxytoluene to develop new anxiolytic drugs. Here, we conduct molecular dynamics simulations, docking studies, receptor binding assays, and in silico ADMET profiling of LQFM289 before its behavioral and biochemical assessment in mice within the dose range of 5-20 mg/kg. The docking of LQFM289 showed strong interactions with the benzodiazepine binding sites and matched well with receptor binding data. With the ADMET profile of this trimetozine derivative that predicts a high intestinal absorption and permeability to blood-brain barrier without being inhibited by the permeability glycoprotein, the oral administration of LQFM289 10 mg/kg consistently induced anxiolytic-like behavior of the mice exposed to the open field and light-dark box apparatus without eliciting motor incoordination in the wire, rotarod, and chimney tests. A decrease in the wire and rotarod´s fall latency coupled with an increase in the chimney test´s climbing time and a decrease in the number of crossings in the open field apparatus at the dose of 20 mg/kg of this trimetozine derivative suggest sedative or motor coordination impairment at this highest dose. The attenuation of the anxiolytic-like effects of LQFM289 (10 mg/kg) by flumazenil pretreatment implicates the participation of benzodiazepine binding sites. The lowering of corticosterone and tumor necrosis factor alpha (cytokine) in LQFM289-treated mice at a single oral (acute) dose of 10 mg/kg suggests that the anxiolytic-like effect of this compound also involves the recruitment of non-benzodiazepine binding sites/GABAergic molecular machinery.


Assuntos
Ansiolíticos , Camundongos , Animais , Ansiolíticos/farmacologia , Ansiolíticos/uso terapêutico , Benzodiazepinas/farmacologia , Hipnóticos e Sedativos/farmacologia , Ansiedade/tratamento farmacológico , Morfolinas/farmacologia , Comportamento Animal
2.
Curr Pharm Des ; 28(8): 655-660, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-32900346

RESUMO

BACKGROUND: Gastric ulcer has been a major cause of morbidity and mortality worldwide, and it has been linked to factors such as nutritional deficiency, smoking, stress, and continuous intake of non-steroidal antiinflammatory drugs (NSAIDs). The search for new anti-ulcer therapeutic agents has been the subject of several studies. Recently, the gastroprotective effect of Celtis iguanaea has been reported, with linoleic acid (LA) responsible for many of the therapeutic effects of this medicinal plant. AIMS: This study aims to investigate the gastroprotective activity and the possible mechanisms in which LA may be involved through different experimental assays in mice. METHODS: The gastroprotective activity of LA was evaluated in the ulcer induced by indomethacin, HCl/EtOH, hypothermic-restraint stress and pyloric ligation. For the investigation of gastroprotective mechanisms, the quantification of the volume (mL), pH and total acidity of gastric secretion were considered. RESULTS: The oral administrations of 25 mg/kg, 50 mg/kg or 100 mg/kg of body weight of LA were capable of protecting the gastric mucosa against HCl/ethanol (10 mL/kg p.o.), and oral/intraduodenal treatment administrations of 50 mg/kg LA showed protection from ulcers induced by indomethacin, hypothermic-restraint stress and pyloric ligation. CONCLUSION: The results of this study show the gastroprotective role of LA in gastric mucosal damage induced by all assayed distresses. The observed gastroprotection possibly occurs due to the mediated increase of mucosal defensive factors.


Assuntos
Antiulcerosos , Úlcera Gástrica , Animais , Antiulcerosos/farmacologia , Antiulcerosos/uso terapêutico , Modelos Animais de Doenças , Etanol/efeitos adversos , Mucosa Gástrica , Humanos , Indometacina/efeitos adversos , Ácido Linoleico/efeitos adversos , Camundongos , Extratos Vegetais/farmacologia , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/tratamento farmacológico
3.
Neuropeptides ; 81: 102027, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32059939

RESUMO

Mastoparan-L (mast-L) is a cell-penetrating tetradecapeptide and stimulator of monoamine exocytosis. In the present study, we evaluated the anxiolytic-like effect of mast-L. Preliminary pharmacological tests were conducted to determine the most appropriate route of administration, extrapolate dose and detect potential toxic effects of this peptide. Oral and intracerebroventricular administration of mast-L (0.1, 0.3 or 0.9 mg.kg-1), diazepam (1 or 5 mg.kg-1), buspirone (10 mg.kg-1) or vehicle 10 mL.kg-1 was carried out prior to the exposure of mice to the anxiety models: open field, light-dark box and elevated plus-maze. To characterize the mechanism underlying the antianxiety-like effect of mast-L, pharmacological antagonism, blood plasma analysis, molecular docking, and receptor binding assays were performed. The absence of a neurotoxic sign, animal's death as well as lack of significant changes in the relative organ weight, hematological and biochemical parameters suggest that mast-L is relatively safe. The anxiolytic-like effect of mast-L was attenuated by flumazenil (antagonist of benzodiazepine binding site) and WAY100635 (selective antagonist of 5-HT1A receptors) pretreatments. Mast-L reduced plasma corticosterone and lowered the scoring function at GABAA -18.48 kcal/mol (Ki = 155 nM), 5-HT1A -22.39 kcal/mol (Ki = 130 nM), corticotropin-releasing factor receptor subtype 1 (CRF1) -11.95 kcal/mol (Ki = 299 nM) and glucocorticoid receptors (GR) -14.69 kcal/mol (Ki = 3552 nM). These data fit the binding affinity (Ki) and demonstrate the involvement of gabaergic, serotonergic and glucocorticoid mechanisms in the anxiolytic-like property of mast-L.


Assuntos
Ansiolíticos/administração & dosagem , Ansiolíticos/farmacologia , Ansiedade/metabolismo , Glucocorticoides/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/administração & dosagem , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Serotonina/metabolismo , Venenos de Vespas/administração & dosagem , Venenos de Vespas/farmacologia , Ácido gama-Aminobutírico/metabolismo , Animais , Comportamento Animal/efeitos dos fármacos , Feminino , Masculino , Camundongos , Receptor 5-HT1A de Serotonina/metabolismo , Receptores de GABA-A/metabolismo
4.
Artigo em Inglês | MEDLINE | ID: mdl-30652655

RESUMO

BACKGROUND: Arginine is considered a semi-essential amino acid in healthy adults and the elderly. This amino acid seems to improve the immune system, stimulate cell growth and differentiation, and increase endothelial permeability, among other effects. For those reasons, it has been theorized that arginine supplementation may be used as an adjuvant to conventional cancer therapy treatments. OBJECTIVE: This review aims to evaluate the existing knowledge of the scientific community on arginine supplementation in order to improve the efficacy of current cancer treatment. RESULTS: Despite the continued efforts of science to improve treatment strategies, cancer remains one of the greatest causes of death on the planet in adults and elderly people. Chemo and radiotherapy are still the most effective treatments but at the cost of significant side effects. CONCLUSION: Thus, new therapeutic perspectives have been studied in recent years, to be used in addition to traditional treatments or not, seeking to treat or even cure the various types of cancer with fewer side effects.


Assuntos
Antineoplásicos/administração & dosagem , Arginina/administração & dosagem , Suplementos Nutricionais , Neoplasias/tratamento farmacológico , Animais , Humanos , Neoplasias/diagnóstico , Neoplasias/metabolismo , Resultado do Tratamento
5.
Microorganisms ; 6(2)2018 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-29710773

RESUMO

Protease inhibitors have a broad biotechnological application ranging from medical drugs to anti-microbial agents. The Inga laurina trypsin inhibitor (ILTI) previously showed a great in vitro inhibitory effect under the adherence of Staphylococcus species, being a strong candidate for use as an anti-biofilm agent. Nevertheless, this is found in small quantities in its sources, which impairs its utilization at an industrial scale. Within this context, heterologous production using recombinant microorganisms is one of the best options to scale up the recombinant protein production. Thus, this work aimed at utilizing Komagataella phaffii to produce recombinant ILTI. For this, the vector pPIC9K+ILTI was constructed and inserted into the genome of the yeast K. phaffii, strain GS115. The protein expression was highest after 48 h using methanol 1%. A matrix-assisted laser desorption ionization⁻time-of-flight (MALDI⁻TOF) analysis was performed to confirm the production of the recombinant ILTI and its activity was investigated trough inhibitory assays using the synthetic substrate Nα-Benzoyl-D,L-arginine p-nitroanilide hydrochloride (BAPNA). Finally, recombinant ILTI (rILTI) was used in assays, showing that there was no significant difference between native and recombinant ILTI in its inhibitory activity in biofilm formation. Anti-tumor assay against Ehrlich ascites tumor (EAT) cells showed that rILTI has a potential anti-tumoral effect, showing the same effect as Melittin when incubated for 48 h in concentrations above 25 µg/mL. All together the results suggests broad applications for rILTI.

6.
Drug Discov Today ; 23(9): 1666-1671, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29803935

RESUMO

Since the early 19th century, host-defense peptides (HDPs) have been known to play a crucial role in innate host defense. Subsequent work has demonstrated their role in adaptive immunity as well as their involvement in cancer and also a number of inflammatory and/or autoimmune diseases. In addition to these multiple functional activities, several studies have shown that HDP accumulation might be correlated with various human diseases and, therefore, could be used as a biomarkers for such. Thus, research has aimed to validate the clinical use of HDPs for diagnosis, prognosis, and further treatment. In this review, we outline the most recent findings related to the use of HDPs as biomarkers, their clinical and epidemiological value, and the techniques used to determine the levels of HDPs.


Assuntos
Peptídeos Catiônicos Antimicrobianos/metabolismo , Doenças do Sistema Imunitário/diagnóstico , Doenças do Sistema Imunitário/metabolismo , Imunidade Adaptativa , Peptídeos Catiônicos Antimicrobianos/imunologia , Bactérias/imunologia , Bactérias/metabolismo , Biomarcadores/metabolismo , Diagnóstico Precoce , Interações Hospedeiro-Patógeno , Humanos , Doenças do Sistema Imunitário/imunologia , Doenças do Sistema Imunitário/terapia , Imunidade Inata , Valor Preditivo dos Testes , Prognóstico
7.
Biofouling ; 33(10): 881-891, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-29047302

RESUMO

Amniotic membrane (AM) is frequently used in ophthalmologic surgery for rapid ocular surface reconstruction. Sometimes it may create a major problem with associated infections after biofilm formation over the membrane. To overcome this problem, AM was coated with the antimicrobial peptide clavanin A. The antifungal activity of clavanin A in the native and self-assembled form was determined against the common ocular surface pathogens Candida albicans, Aspergillus fumigatus, Alternaria sp. and Fusarium sp. Biofilm formation over the coated surface was significantly reduced in comparison with the uncoated membrane. The coated membrane revealed effectiveness in terms of biocompatibility, cell attachment colonization when tested in non-cancerous 3T3 and human embryonic kidney (HEK)-293 cell lines. Clavanin A-coated AM also exhibited excellent physical, morphological and antifungal characteristics, indicating potential applicability for ocular surface infection control.


Assuntos
Âmnio/microbiologia , Antifúngicos/farmacologia , Biofilmes/efeitos dos fármacos , Proteínas Sanguíneas/farmacologia , Alternaria/efeitos dos fármacos , Alternaria/fisiologia , Âmnio/transplante , Antibacterianos , Aspergillus fumigatus/efeitos dos fármacos , Aspergillus fumigatus/fisiologia , Candida albicans/efeitos dos fármacos , Fusarium/efeitos dos fármacos , Fusarium/fisiologia , Células HEK293 , Humanos
8.
Pharmacol Ther ; 178: 132-140, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28435091

RESUMO

Antimicrobial peptides (AMPs) have evolved through billions of years as part of our innate immune system. These agents are produced by various cells throughout the human body and play important roles in our ability to respond to infections. In this review, we outline evidence linking AMP expression with a range of inflammatory and autoimmune human diseases. Finally, we highlight the promise of endogenous AMP induction for the treatment of disease (i.e., host-directed therapy) and briefly mention the different peptide drugs that are currently undergoing clinical trials.


Assuntos
Peptídeos Catiônicos Antimicrobianos/imunologia , Imunidade Adaptativa , Anti-Infecciosos/uso terapêutico , Peptídeos Catiônicos Antimicrobianos/uso terapêutico , Humanos , Imunidade Inata , Fatores Imunológicos/uso terapêutico , Imunoterapia
9.
Front Chem ; 5: 5, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28271058

RESUMO

In recent years, the number of people suffering from cancer and multi-resistant infections has increased, such that both diseases are already seen as current and future major causes of death. Moreover, chronic infections are one of the main causes of cancer, due to the instability in the immune system that allows cancer cells to proliferate. Likewise, the physical debility associated with cancer or with anticancer therapy itself often paves the way for opportunistic infections. It is urgent to develop new therapeutic methods, with higher efficiency and lower side effects. Antimicrobial peptides (AMPs) are found in the innate immune system of a wide range of organisms. Identified as the most promising alternative to conventional molecules used nowadays against infections, some of them have been shown to have dual activity, both as antimicrobial and anticancer peptides (ACPs). Highly cationic and amphipathic, they have demonstrated efficacy against both conditions, with the number of nature-driven or synthetically designed peptides increasing year by year. With similar properties, AMPs that can also act as ACPs are viewed as future chemotherapeutic drugs, with the advantage of low propensity to resistance, which started this paradigm in the pharmaceutical market. These peptides have already been described as molecules presenting killing mechanisms at the membrane level, but also acting toward intracellular targets, which increases their success compartively to one-target specific drugs. This review will approach the desirable characteristics of small peptides that demonstrated dual activity against microbial infections and cancer, as well as the peptides engaged in clinical trials.

10.
Int J Antimicrob Agents ; 49(2): 167-175, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28108242

RESUMO

Mastoparans, a class of peptides found in wasp venom, have significant effects following a sting as well as useful applications in clinical practice. Among these is their potential use in the control of micro-organisms that cause infectious diseases with a significant impact on society. Thus, the present study describes the isolation and identification of a mastoparan peptide from the venom of the social wasp Pseudopolybia vespiceps and evaluated its antimicrobial profile against bacteria (Staphylococcus aureus and Mycobacterium abscessus subsp. massiliense), fungi (Candida albicans and Cryptococcus neoformans) and in vivo S. aureus infection. The membrane pore-forming ability was also assessed. The mastoparan reduced in vitro and ex vivo mycobacterial growth by 80% at 12.5 µM in infected peritoneal macrophages but did not affect the shape of bacterial cells at the dose tested (6.25 µM). The peptide also showed potent action against S. aureus in vitro (EC50 and EC90 values of 1.83 µM and 2.90 µM, respectively) and reduced the in vivo bacterial load after 6 days of topical treatment (5 mg/kg). Antifungal activity was significant, with EC50 and EC90 values of 12.9 µM and 15.3 µM, respectively, for C. albicans, and 11 µM and 22.70 µM, respectively, for C. neoformans. Peptides are currently attracting interest for their potential in the design of antimicrobial drugs, particularly due to the difficulty of micro-organisms in developing resistance to them. In this respect, Polybia-MPII proved to be highly effective, with a lower haemolysis rate compared with peptides of the same family.


Assuntos
Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Fungos/efeitos dos fármacos , Peptídeos/farmacologia , Infecções Estafilocócicas/tratamento farmacológico , Venenos de Vespas/farmacologia , Vespas/química , Administração Tópica , Animais , Anti-Infecciosos/isolamento & purificação , Modelos Animais de Doenças , Feminino , Voluntários Saudáveis , Humanos , Peptídeos e Proteínas de Sinalização Intercelular , Macrófagos Peritoneais/microbiologia , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Peptídeos/isolamento & purificação , Resultado do Tratamento , Venenos de Vespas/isolamento & purificação
11.
J Nat Prod ; 79(11): 2767-2773, 2016 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-27809507

RESUMO

The extraction and purification of parigidin-br3, a cyclotide analogue belonging to the "bracelet" subfamily, from Palicourea rigida leaves is discussed. Unlike conventional cyclotides, parigidin-br3 has free N- and C-termini, as identified by MALDI-TOF/TOF analysis and confirmed by gene structure elucidation, and is one of a small number of acyclotides discovered during recent years. Parigidin-br3 showed cytotoxic activity against MCF-7 (breast cancer) and CACO2 (colorectal adenocarcinoma) cells, with IC50 values of ∼2.5 µM and less than 10% hemolytic activity. Overall, parigidin-br3 is a promising new molecule with cytotoxic properties against tumor cell lines and, unlike many synthetic acyclic analogues, demonstrates that cytotoxic activity is not limited to conventional (i.e., cyclic) cyclotides.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Rubiaceae/química , Sequência de Aminoácidos , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Células CACO-2 , Neoplasias Colorretais/tratamento farmacológico , Ciclotídeos/química , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Concentração Inibidora 50 , Dados de Sequência Molecular , Estrutura Molecular , Folhas de Planta/química , Proteínas de Plantas/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
12.
Antimicrob Agents Chemother ; 59(3): 1620-6, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25547358

RESUMO

The rapid increase in the incidence of multidrug-resistant infections today has led to enormous interest in antimicrobial peptides (AMPs) as suitable compounds for developing unusual antibiotics. In this study, clavanin A, an antimicrobial peptide previously isolated from the marine tunicate Styela clava, was selected as a purposeful molecule that could be used in controlling infection and further synthesized. Clavanin A was in vitro evaluated against Staphylococcus aureus and Escherichia coli as well as toward L929 mouse fibroblasts and skin primary cells (SPCs). Moreover, this peptide was challenged here in an in vivo wound and sepsis model, and the immune response was also analyzed. Despite displaying clear in vitro antimicrobial activity toward Gram-positive and -negative bacteria, clavanin A showed no cytotoxic activities against mammalian cells, and in acute toxicity tests, no adverse reaction was observed at any of the concentrations. Moreover, clavanin A significantly reduced the S. aureus CFU in an experimental wound model. This peptide also reduced the mortality of mice infected with E. coli and S. aureus by 80% compared with that of control animals (treated with phosphate-buffered saline [PBS]): these data suggest that clavanin A prevents the start of sepsis and thereby reduces mortality. These data suggest that clavanin A is an AMP that could improve the development of novel peptide-based strategies for the treatment of wound and sepsis infections.


Assuntos
Anti-Infecciosos/farmacologia , Proteínas Sanguíneas/farmacologia , Infecções por Escherichia coli/tratamento farmacológico , Escherichia coli/efeitos dos fármacos , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/efeitos dos fármacos , Animais , Camundongos , Camundongos Endogâmicos C57BL , Peptídeos/farmacologia
13.
Int J Nanomedicine ; 9: 5055-69, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25382976

RESUMO

Controlling human pathogenic bacteria is a worldwide problem due to increasing bacterial resistance. This has prompted a number of studies investigating peptides isolated from marine animals as a possible alternative for control of human pathogen infections. Clavanins are antimicrobial peptides isolated from the marine tunicate Styela clava, showing 23 amino acid residues in length, cationic properties, and also high bactericidal activity. In spite of clear benefits from the use of peptides, currently 95% of peptide properties have limited pharmaceutical applicability, such as low solubility and short half-life in the circulatory system. Here, nanobiotechnology was used to encapsulate clavanin A in order to develop nanoantibiotics against bacterial sepsis. Clavanin was nanostructured using EUDRAGIT(®) L 100-55 and RS 30 D solution (3:1 w:w). Atomic force, scanning electron microscopy and dynamic light scattering showed nanoparticles ranging from 120 to 372 nm in diameter, with a zeta potential of -7.16 mV and a polydispersity index of 0.123. Encapsulation rate of 98% was assessed by reversed-phase chromatography. In vitro bioassays showed that the nanostructured clavanin was partially able to control development of Staphylococcus aureus, Klebsiella pneumoniae, and Pseudomonas aeruginosa. Furthermore, nanostructures did not show hemolytic activity. In vivo sepsis bioassays were performed using C57BL6 mice strain inoculated with a polymicrobial suspension. Assays led to 100% survival rate under sub-lethal sepsis assays and 40% under lethal sepsis assays in the presence of nanoformulated clavanin A until the seventh day of the experiment. Data here reported indicated that nanostructured clavanin A form shows improved antimicrobial activity and has the potential to be used to treat polymicrobial infections.


Assuntos
Antibacterianos/administração & dosagem , Peptídeos Catiônicos Antimicrobianos/administração & dosagem , Bacteriemia/tratamento farmacológico , Proteínas Sanguíneas/administração & dosagem , Metacrilatos/administração & dosagem , Nanopartículas/química , Animais , Antibacterianos/química , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/isolamento & purificação , Bactérias/efeitos dos fármacos , Proteínas Sanguíneas/química , Linhagem Celular Tumoral , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/química , Metacrilatos/química , Camundongos , Camundongos Endogâmicos C57BL , Nanopartículas/administração & dosagem , Nanotecnologia , Urocordados/química
14.
Sci Rep ; 4: 6015, 2014 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-25109311

RESUMO

Peptide rational design was used here to guide the creation of two novel short ß-lactamase inhibitors, here named dBLIP-1 and -2, with length of five amino acid residues. Molecular modeling associated with peptide synthesis improved bactericidal efficacy in addition to amoxicillin, ampicillin and cefotaxime. Docked structures were consistent with calorimetric analyses against bacterial ß-lactamases. These two compounds were further tested in mice. Whereas commercial antibiotics alone failed to cure mice infected with Staphylococcus aureus and Escherichia coli expressing ß-lactamases, infection was cleared when treated with antibiotics in combination with dBLIPs, clearly suggesting that peptides were able to neutralize bacterial resistance. Moreover, immunological assays were also performed showing that dBLIPs were unable to modify mammalian immune response in both models, reducing the risks of collateral effects. In summary, the unusual peptides here described provide leads to overcome ß-lactamase-based resistance, a remarkable clinical challenge.


Assuntos
Desenho de Fármacos , Peptídeos/química , Inibidores de beta-Lactamases/química , beta-Lactamases/química , Animais , Antibacterianos/farmacologia , Bacillus cereus/efeitos dos fármacos , Bacillus cereus/enzimologia , Sítios de Ligação , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Farmacorresistência Bacteriana/efeitos dos fármacos , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Escherichia coli/enzimologia , Cinética , Camundongos , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Peptídeos/metabolismo , Peptídeos/toxicidade , Estrutura Terciária de Proteína , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/enzimologia , Inibidores de beta-Lactamases/metabolismo , Inibidores de beta-Lactamases/farmacologia , beta-Lactamases/metabolismo
15.
Drug Discov Today ; 19(8): 1045-50, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24881782

RESUMO

Bacterial infectious diseases are currently a serious health problem, especially in patients compromised by illness or those receiving immune-suppressant drugs. In this context, it is not only essential to improve the understanding of infectious mechanisms and host response but also to discover novel therapies with extreme urgency. Probiotics and antimicrobial peptides are also favorably viewed as novel strategies in the control of resistant bacteria. The present review will shed some light on the use of probiotic microorganisms expressing antimicrobial peptides as a dual therapy to control bacterial infectious diseases.


Assuntos
Anti-Infecciosos/imunologia , Anti-Infecciosos/uso terapêutico , Hospedeiro Imunocomprometido/imunologia , Peptídeos/imunologia , Probióticos/farmacologia , Probióticos/uso terapêutico , Proteínas Recombinantes/imunologia , Animais , Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/imunologia , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/imunologia , Humanos , Hospedeiro Imunocomprometido/efeitos dos fármacos , Peptídeos/farmacologia , Peptídeos/uso terapêutico , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/uso terapêutico
16.
J Cell Physiol ; 228(12): 2271-84, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24037769

RESUMO

Despite all the dental information acquired over centuries and the importance of proteome research, the cross-link between these two areas only emerged around mid-nineties. Proteomic tools can help dentistry in the identification of risk factors, early diagnosis, prevention, and systematic control that will promote the evolution of treatment in all dentistry specialties. This review mainly focuses on the evolution of dentistry in different specialties based on proteomic research and how these tools can improve knowledge in dentistry. The subjects covered are an overview of proteomics in dentistry, specific information on different fields in dentistry (dental structure, restorative dentistry, endodontics, periodontics, oral pathology, oral surgery, and orthodontics) and future directions. There are many new proteomic technologies that have never been used in dentistry studies and some dentistry areas that have never been explored by proteomic tools. It is expected that a greater integration of these areas will help to understand what is still unknown in oral health and disease.


Assuntos
Odontologia/métodos , Proteoma/genética , Proteoma/metabolismo , Proteômica/métodos , Animais , Assistência Odontológica/métodos , Humanos
17.
PLoS One ; 8(5): e63571, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23737945

RESUMO

Inhibitors of peptidases isolated from leguminous seeds have been studied for their pharmacological properties. The present study focused on purification, biochemical characterization and anti-inflammatory and anticoagulant evaluation of a novel Kunitz trypsin inhibitor from Erythrina velutina seeds (EvTI). Trypsin inhibitors were purified by ammonium sulfate (30-60%), fractionation followed by Trypsin-Sepharose affinity chromatography and reversed-phase high performance liquid chromatography. The purified inhibitor showed molecular mass of 19,210.48 Da. Furthermore, a second isoform with 19,228.16 Da was also observed. The inhibitor that showed highest trypsin specificity and enhanced recovery yield was named EvTI (P2) and was selected for further analysis. The EvTI peptide fragments, generated by trypsin and pepsin digestion, were further analyzed by MALDI-ToF-ToF mass spectrometry, allowing a partial primary structure elucidation. EvTI exhibited inhibitory activity against trypsin with IC50 of 2.2×10(-8) mol.L(-1) and constant inhibition (Ki) of 1.0×10(-8) mol.L(-1), by a non-competitive mechanism. In addition to inhibit the activity of trypsin, EvTI also inhibited factor Xa and neutrophil elastase, but do not inhibit thrombin, chymotrypsin or peptidase 3. EvTI was investigated for its anti-inflammatory and anti-coagulant properties. Firstly, EvTI showed no cytotoxic effect on human peripheral blood cells. Nevertheless, the inhibitor was able to prolong the clotting time in a dose-dependent manner by using in vitro and in vivo models. Due to anti-inflammatory and anticoagulant EvTI properties, two sepsis models were here challenged. EvTI inhibited leukocyte migration and specifically acted by inhibiting TNF-α release and stimulating IFN-α and IL-12 synthesis. The data presented clearly contribute to a better understanding of the use of Kunitz inhibitors in sepsis as a bioactive agent capable of interfering in blood coagulation and inflammation.


Assuntos
Anti-Inflamatórios/farmacologia , Anticoagulantes/farmacologia , Erythrina/química , Peptídeos/farmacologia , Proteínas de Plantas/farmacologia , Sementes/química , Inibidores da Tripsina/farmacologia , Sequência de Aminoácidos , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Anticoagulantes/química , Anticoagulantes/isolamento & purificação , Movimento Celular/efeitos dos fármacos , Cromatografia de Afinidade , Citocinas/metabolismo , Avaliação Pré-Clínica de Medicamentos , Escherichia coli/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Contagem de Leucócitos , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Peptídeos/química , Peptídeos/isolamento & purificação , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Proteínas de Plantas/química , Proteínas de Plantas/isolamento & purificação , Estabilidade Proteica , Sepse/tratamento farmacológico , Sepse/imunologia , Homologia de Sequência de Aminoácidos , Especificidade por Substrato , Tripsina/química , Inibidores da Tripsina/química , Inibidores da Tripsina/isolamento & purificação
18.
Peptides ; 42: 144-8, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23416023

RESUMO

In several organisms, the first barrier against microbial infections consists of antimicrobial peptides (AMPs) which are molecules that act as components of the innate immune system. Recent studies have demonstrated that AMPs can perform various functions in different tissues or physiological conditions. In this view, this study was carried out in order to evaluate the multifunctional activity in vivo of an alanine-rich peptide, known as Pa-MAP, derived from the polar fish Pleuronectes americanus. Pa-MAP was evaluated in intraperitoneally infected mice with a sub-lethal concentration of Escherichia coli at standard concentrations of 1 and 5 mg kg(-1). At both concentrations, Pa-MAPs exhibited an ability to prevent E. coli infection and increase mice survival, similar to the result observed in mice treated with ampicillin at 2 mg kg(-1). In addition, mice were monitored for weight loss. The results showed that mice treated with Pa-MAPs at 1 mg kg(-1) gained 0.8% of body weight during the 72 h of experiment. The same was observed with Pa-MAP at 5 mg kg(-1), which had a gain of 0.5% in body weight during the treatment. Mice treated with ampicillin at 2 mg kg(-1) show a significant weight loss of 5.6% of body weight. The untreated group exhibited a 5.5% loss of body weight. The immunomodulatory effects were also evaluated by the quantification of IL-10, IL-12, TNF-α, IFN-γ and nitric oxide cytokines in serum, but no immunomodulatory activity was observed. Data presented here suggest that Pa-MAP should be used as a novel antibiotic against infection control.


Assuntos
Anti-Infecciosos/farmacologia , Proteínas de Peixes/química , Linguado/metabolismo , Peptídeos/farmacologia , Sequência de Aminoácidos , Ampicilina/farmacologia , Animais , Anti-Infecciosos/química , Peso Corporal/efeitos dos fármacos , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos/métodos , Infecções por Escherichia coli/tratamento farmacológico , Feminino , Fatores Imunológicos/farmacologia , Interleucina-10/imunologia , Interleucina-10/metabolismo , Interleucina-12/imunologia , Interleucina-12/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Peptídeos/química , Fator de Necrose Tumoral alfa/imunologia , Fator de Necrose Tumoral alfa/metabolismo
19.
Biopolymers ; 98(4): 322-31, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23193596

RESUMO

The antimicrobial peptides (AMPs) are evolutionarily ancient molecules that act as components of the innate immune system. Recently, it was demonstrated that a single AMP can perform various functions; this ability is known as "peptide promiscuity." However, little is known about promiscuity in plant AMPs without disulfide bonds. This study was carried out to evaluate the promiscuity of Cn-AMP1: a promising disulfide-free plant peptide with reduced size and cationic and hydrophobic properties. Its activity against human pathogenic bacteria and fungal pathogens, as well as its in vitro immunostimulatory activity and effects on cancerous and healthy mammalian cell proliferation were studied here. Cn-AMP1 exerts antimicrobial effects against Gram-positive bacteria, Gram-negative bacteria, and fungi. Moreover, tumor cell viability activity in Caco-2 cells, as well as immunostimulatory activity by evaluating upregulated inflammatory-cytokine secretion by monocytes was also positively observed. Cn-AMP1 does not exhibit a well-defined conformation in aqueous solution and probably undergoes a 3(10)-helix transition in hydrophobic environments. The experimental results support the promiscuous activity of Cn-AMP1, presenting a wide range of activities, including antibacterial, antifungal, and immunostimulatory activity. In the future, Cn-AMP1 should be used in the development of novel biopharmaceuticals, mainly due to its reduced size and broad spectrum of activity.


Assuntos
Anti-Infecciosos/farmacologia , Peptídeos/farmacologia , Adjuvantes Imunológicos/química , Adjuvantes Imunológicos/farmacologia , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Anti-Infecciosos/química , Antifúngicos/química , Antifúngicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Peptídeos/química
20.
PLoS One ; 7(10): e47047, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23056574

RESUMO

Recently, defense peptides that are able to act against several targets have been characterized. The present work focuses on structural and functional evaluation of the peptide analogue Pa-MAP, previously isolated as an antifreeze peptide from Pleuronectes americanus. Pa-MAP showed activities against different targets such as tumoral cells in culture (CACO-2, MCF-7 and HCT-116), bacteria (Escherichia coli ATCC 8739 and Staphylococcus aureus ATCC 25923), viruses (HSV-1 and HSV-2) and fungi (Candida parapsilosis ATCC 22019, Trichophyton mentagrophytes (28d&E) and T. rubrum (327)). This peptide did not show toxicity against mammalian cells such as erythrocytes, Vero and RAW 264.7 cells. Molecular mechanism of action was related to hydrophobic residues, since only the terminal amino group is charged at pH 7 as confirmed by potentiometric titration. In order to shed some light on its structure-function relations, in vitro and in silico assays were carried out using circular dichroism and molecular dynamics. Furthermore, Pa-MAP showed partial unfolding of the peptide changes in a wide pH (3 to 11) and temperature (25 to 95°C) ranges, although it might not reach complete unfolding at 95°C, suggesting a high conformational stability. This peptide also showed a conformational transition with a partial α-helical fold in water and a full α-helical core in SDS and TFE environments. These results were corroborated by spectral data measured at 222 nm and by 50 ns dynamic simulation. In conclusion, data reported here show that Pa-MAP is a potential candidate for drug design against pathogenic microorganisms due to its structural stability and wide activity against a range of targets.


Assuntos
Alanina/química , Linguado/metabolismo , Peptídeos/química , Peptídeos/farmacologia , Animais , Células CACO-2 , Candida/efeitos dos fármacos , Linhagem Celular , Eritrócitos/efeitos dos fármacos , Células HCT116 , Humanos , Staphylococcus aureus/efeitos dos fármacos , Trichophyton/efeitos dos fármacos
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