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1.
PLoS One ; 14(12): e0220422, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31841562

RESUMO

Benthic cyanobacterial proliferations in rivers are have been reported with increasing frequency worldwide. In the Eel and Russian rivers of California, more than a dozen dog deaths have been attributed to cyanotoxin toxicosis since 2000. Periphyton proliferations in these rivers comprise multiple cyanobacterial taxa capable of cyanotoxin production, hence there is uncertainty regarding which taxa are producing toxins. In this study, periphyton samples dominated by the cyanobacterial genera Anabaena spp. and Microcoleus spp. and the green alga Cladophora glomerata were collected from four sites in the Eel River catchment and one site in the Russian River. Samples were analysed for potential cyanotoxin producers using polymerase chain reaction (PCR) in concert with Sanger sequencing. Cyanotoxin concentrations were measured using liquid chromatography tandem-mass spectrometry, and anatoxin quota (the amount of cyanobacterial anatoxins per toxigenic cell) determined using droplet digital PCR. Sequencing indicated Microcoleus sp. and Nodularia sp. were the putative producers of cyanobacterial anatoxins and nodularins, respectively, regardless of the dominant taxa in the mat. Anatoxin concentrations in the mat samples varied from 0.1 to 18.6 µg g-1 and were significantly different among sites (p < 0.01, Wilcoxon test); however, anatoxin quotas were less variable (< 5-fold). Dihydroanatoxin-a was generally the most abundant variant in samples comprising 38% to 71% of the total anatoxins measured. Mats dominated by the green alga C. glomerata contained both anatoxins and nodularin-R at concentrations similar to those of cyanobacteria-dominated mats. This highlights that even when cyanobacteria are not the dominant taxa in periphyton, these mats may still pose a serious health risk and indicates that more widespread monitoring of all mats in a river are necessary.


Assuntos
Toxinas Bacterianas/análise , Cianobactérias/patogenicidade , Rios/química , Anabaena/patogenicidade , California , Clorófitas/genética , Clorófitas/metabolismo , Cromatografia Líquida , Cianobactérias/genética , Cianobactérias/metabolismo , Reação em Cadeia da Polimerase , Prolina/análogos & derivados , Prolina/análise , Microbiologia da Água
2.
Chem Commun (Camb) ; 55(83): 12487-12490, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31566647

RESUMO

CF2H-Pseudoprolines obtained from difluoroacetaldehyde hemiacetal and serine are stable proline surrogates. The consequence of the incorporation of the CF2H group is an important decrease of the trans to cis amide bond isomerization energy and a remarkable stabilisation of the cis conformer by an hydrogen bond.


Assuntos
Peptídeos/química , Prolina/análogos & derivados , Tiazóis/química , Tolueno/análogos & derivados , Ligações de Hidrogênio , Metilação , Conformação Molecular , Prolina/química , Estereoisomerismo , Tolueno/química
3.
Chem Pharm Bull (Tokyo) ; 67(10): 1139-1143, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31582633

RESUMO

We have discovered that ß-amino acid homooligomers with cis- or trans-amide conformation can fold themselves into highly ordered helices. Moreover, unlike α-amino acid peptides, which are significantly stabilized by intramolecular hydrogen bonding, these helical structures are autogenous conformations that are stable without the aid of hydrogen bonding and irrespective of solvent (protic/aprotic/halogenated) or temperature. A structural overlap comparison of helical cis/trans bicyclic ß-proline homooligomers with typical α-helix structure of α-amino acid peptides reveals clear differences of pitch and diameter per turn. Bridgehead substituents of the present homooligomers point outwards from the helical surface. We were interested to know whether such non-naturally occurring divergent helical molecules could mimic α-helix structures. In this study, we show that bicyclic ß-proline oligomer derivatives inhibit p53-MDM2 and p53-MDMX protein-protein interactions, exhibiting MDM2-antagonistic and MDMX-antagonistic activities.


Assuntos
Proteínas Nucleares/química , Proteínas Proto-Oncogênicas c-mdm2/química , Proteínas Proto-Oncogênicas/química , Proteína Supressora de Tumor p53/química , Proteínas de Ciclo Celular , Humanos , Estrutura Molecular , Proteínas Nucleares/antagonistas & inibidores , Prolina/análogos & derivados , Prolina/farmacologia , Ligação Proteica/efeitos dos fármacos , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-mdm2/antagonistas & inibidores , Proteína Supressora de Tumor p53/antagonistas & inibidores
4.
Chemistry ; 25(69): 15759-15764, 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31628819

RESUMO

A general and robust method for the incorporation of aspartates with a thioacid side chain into peptides has been developed. Pseudoproline tripeptides served as building blocks for the efficient fluorenylmethyloxycarbonyl (Fmoc) solid-phase synthesis of thioacid-containing peptides. These peptides were readily converted to complex N-glycopeptides by using a fast and chemoselective one-pot deprotection/ligation procedure. Furthermore, a novel side reaction that can lead to site-selective peptide cleavage using thioacids (CUT) was discovered and studied in detail.


Assuntos
Glicopeptídeos/síntese química , Oligopeptídeos/química , Prolina/análogos & derivados , Técnicas de Síntese em Fase Sólida/métodos , Tiazóis/química , Ácidos/química , Sequência de Aminoácidos , Fluorenos/síntese química , Fluorenos/química , Glicopeptídeos/química , Oligopeptídeos/síntese química , Prolina/síntese química , Prolina/química , Compostos de Sulfidrila/química , Tiazóis/síntese química
5.
J Agric Food Chem ; 67(35): 9805-9811, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31407895

RESUMO

Stachydrine (STA) is a constituent of citrus fruits and Leonurus heterophyllus Sweet. In the present study, we established that STA caused acute endothelium-dependent relaxation. The vascular action of STA was mediated by nitric oxide (NO) via cyclic guanosine monophosphate. Mechanistically, STA activated AMP-activated protein kinase (AMPK), protein kinase B/Akt, and endothelial NO synthase (eNOS) in vascular endothelial cells (ECs). AMPK inhibition by compound C blocked STA-induced Akt/eNOS phosphorylation, suggesting that AMPK is the upstream of Akt and eNOS. Inhibition of Akt by MK2206 blocked STA-stimulated eNOS phosphorylation without altering AMPK phosphorylation. Furthermore, we showed that STA activated AMPK via the induction of liver kinase B1 phosphorylation. These results indicated that STA can induce eNOS phosphorylation and vasorelaxation by regulating the interplay between AMPK and Akt pathways in ECs. These findings further highlighted the potential of STA as a nutritional factor in the beneficial effects of fruit intake in preventing the endothelial dysfunction-related metabolic cardiovascular diseases.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Aorta Torácica/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Óxido Nítrico Sintase Tipo III/metabolismo , Prolina/análogos & derivados , Proteínas Proto-Oncogênicas c-akt/metabolismo , Vasodilatadores/farmacologia , Proteínas Quinases Ativadas por AMP/genética , Animais , Aorta Torácica/metabolismo , Aorta Torácica/fisiopatologia , Bovinos , Citrus/química , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Técnicas In Vitro , Leonurus/química , Masculino , Óxido Nítrico Sintase Tipo III/genética , Fosforilação/efeitos dos fármacos , Prolina/farmacologia , Proteínas Proto-Oncogênicas c-akt/genética , Ratos , Ratos Sprague-Dawley , Vasodilatação/efeitos dos fármacos
6.
Molecules ; 24(12)2019 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-31200582

RESUMO

A novel special designed, stable, and recyclable chiral ligand bearing a quaternary carbon was developed for chemical dynamic kinetic resolution (DKR) of free C,N-unprotected racemic α-amino acids via Schiff base intermediates. This method furnishes high yields with excellent enantioselectivity, has a broad substrate scope, and uses operationally simple and convenient conditions. The present chemical DKR is a practical and useful method for the preparation of enantiopure α-amino acids.


Assuntos
Aminoácidos/química , Prolina/análogos & derivados , Bases de Schiff/química , Carbono/química , Cinética , Prolina/química , Estereoisomerismo
7.
Nucl Med Commun ; 40(4): 383-387, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30875335

RESUMO

OBJECTIVES: This study aimed to investigate whether the amino acid PET tracer cis-4-[F]fluoro-D-proline [D-cis-[F]FPro] shows increased uptake in the basal ganglia of patients with neurodegenerative akinetic-rigid parkinsonism. D-Cis-[F]FPro is a sensitive PET tracer for inflammation-associated neurodegeneration in animal models. We hypothesized that D-cis-[F]FPro might also be a sensitive marker of alterations of the basal ganglia in parkinsonian syndromes. PARTICIPANTS AND METHODS: Ten patients with neurodegenerative akinetic-rigid parkinsonism (five with idiopathic Parkinson's disease and five with atypical parkinsonian syndromes) were imaged with D-cis-[F]FPro and compared with 13 patients with brain tumors who had no basal ganglia involvement. PET images 20-50 min after injection were evaluated and tracer uptake in the basal ganglia was quantified using volume-of-interest analysis with basal ganglia to background ratios. The severity of disease was assessed with unified Parkinson's disease rating scale III and correlated with D-cis-[F]FPro uptake. RESULTS: In patients with parkinsonism, volume-of-interest analysis showed mild, but significantly increased D-cis-[F]FPro uptake in the basal ganglia, pronounced in the lenticular nucleus. Disease severity correlated with D-cis-[F]FPro uptake in the right pallidum (r=-0.687, P=0.041). CONCLUSION: Data suggest that D-cis-[F]FPro is a sensitive marker of inflammation-associated degenerative processes in parkinsonian syndromes.


Assuntos
Transtornos Parkinsonianos/diagnóstico por imagem , Prolina/análogos & derivados , Idoso , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Imagem Multimodal , Transtornos Parkinsonianos/patologia , Transtornos Parkinsonianos/fisiopatologia , Tomografia por Emissão de Pósitrons
8.
J Sep Sci ; 42(9): 1725-1732, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30839168

RESUMO

Leonurus japonicus houtt, a well-known herb of traditional Chinese medicine, is widely used to treat gynaecological diseases. In this study, a rapid and sensitive liquid chromatography with tandem mass spectrometry method for simultaneously quantifying leonurine and stachydrine, the two main bioactive components in Leonurus japonicus houtt, was developed and validated. Plasma samples were prepared by protein precipitation with acetonitrile and separation by a Hewlett Packard XDB-C8 column (150 × 4.6 mm, id, 5 µm) equipped with a gradient elution system containing methanol-water and 0.1% formic acid at a flow-rate of 0.4 mL/min. Components were then detected by a mass spectrometer in positive electrospray ionization mode. This method showed good linearity, precision, accuracy, recovery, stability, and negligible matrix effects, which were within acceptable ranges. The method was successfully applied to compare the pharmacokinetics in normal rats and rats with cold-stagnation and blood-stasis primary dysmenorrhoea treated with Leonurus japonicus houtt electuary. The result showed significant differences (p < 0.05) in the pharmacokinetic parameters between the primary dysmenorrhoea and normal groups. This result implied that Leonurus japonicus houtt electuary remained longer and was absorbed slower in rats with primary dysmenorrhoea and exhibited higher bioavailability and peak concentration.


Assuntos
Medicamentos de Ervas Chinesas/farmacocinética , Dismenorreia/tratamento farmacológico , Ácido Gálico/análogos & derivados , Leonurus/química , Prolina/análogos & derivados , Animais , Medicamentos de Ervas Chinesas/administração & dosagem , Dismenorreia/sangue , Feminino , Ácido Gálico/administração & dosagem , Ácido Gálico/farmacocinética , Humanos , Prolina/administração & dosagem , Prolina/farmacocinética , Ratos , Ratos Sprague-Dawley
9.
Nanomedicine ; 18: 135-145, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30849548

RESUMO

We report here the preparation, physico-chemical characterization, and biological evaluation of a new liposome formulation as a tool for tumor angiogenesis inhibition. Liposomes are loaded with sunitinib, a tyrosine kinase inhibitor, and decorated with cyclo-aminoprolineRGD units (cAmpRGD), efficient and selective ligands for integrin αVß3. The RGD units play multiple roles since they target the nanovehicles at the integrin αVß3-overexpressing cells (e.g. activated endothelial cells), favor their active cell internalization, providing drug accumulation in the cytoplasm, and likely take part in the angiogenesis inhibition by interfering in the αVß3-VEGFR2 cross-talk. Both in vitro and in vivo studies show a better efficacy of this integrated antiangiogenic tool with respect to the free sunitinib and untargeted sunitinib-loaded liposomes. This system could allow a lower administration of the drug and, by increasing the vector specificity, reduce side-effects in a prolonged antiangiogenic therapy.


Assuntos
Inibidores da Angiogênese/farmacologia , Integrina alfaVbeta3/metabolismo , Oligopeptídeos/química , Prolina/análogos & derivados , Sunitinibe/farmacologia , Inibidores da Angiogênese/química , Inibidores da Angiogênese/uso terapêutico , Animais , Adesão Celular/efeitos dos fármacos , Células Progenitoras Endoteliais/citologia , Células Progenitoras Endoteliais/efeitos dos fármacos , Células Progenitoras Endoteliais/metabolismo , Humanos , Recém-Nascido , Lipídeos/química , Lipossomos , Camundongos , Nanopartículas/química , Neovascularização Patológica/tratamento farmacológico , Oligopeptídeos/síntese química , Fosfolipídeos/síntese química , Fosfolipídeos/química , Fosforilação/efeitos dos fármacos , Prolina/síntese química , Prolina/química , Sunitinibe/química , Sunitinibe/uso terapêutico , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Vitronectina/metabolismo
10.
Appl Microbiol Biotechnol ; 103(7): 2985-3000, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30747297

RESUMO

A wide variety of chitosan (CS) biomaterials have been loaded with different antimicrobial agents to improve the activity of CS against phytopathogenic fungi. Recently, the antimicrobial activity of 1H-pyrrole-2-carboxylic acid (PCA) has been reported as a secondary metabolite of Streptomyces griseus, which was identified as the main bioactive compound in the biological control. However, it is sensitive to light and its activity against filamentous fungi has not yet been reported. The aim of the present research work was to evaluate the biological activity of CS-PCA biocomposites for the control of Aspergillus niger. CS-PCA biocomposites were obtained through nanoprecipitation. In vitro antifungal activity was determined by viability assay, spore germination, morphometric analysis of spores and hyphae, and the analysis of cellular components by fluorescence microscopy. CS-PCA showed an average size and Z potential of 502 ± 72 nm and + 54.7 ± 15 mV, respectively. Micrographs demonstrated well-distributed biocomposites with an apparently spherical shape. A new signal at 1473 cm-1 in the FT-IR spectrum of the CS-PCA biocomposite was observed, confirming the presence of PCA in the composition of the CS-PCA nanosystem. CS-PCA biocomposites reduced the spores' viability by up to 58%. Effects on fungi morphometry, observed as an increase in the spores' average diameter, swelling, distortion, and an increase in the branching of hyphae, were observed. Fluorescence analysis showed oxidative stress and membrane and cell wall damage, mainly at early growth stages. The inhibitory effect against CS-resistant fungi, such as A. niger, opens a door for the control of CS-sensitive fungi.


Assuntos
Antifúngicos/farmacologia , Aspergillus niger/efeitos dos fármacos , Quitosana/química , Quitosana/farmacologia , Prolina/análogos & derivados , Antifúngicos/química , Fluorescência , Teste de Materiais , Testes de Sensibilidade Microbiana , Prolina/química , Metabolismo Secundário , Espectroscopia de Infravermelho com Transformada de Fourier , Esporos Fúngicos/crescimento & desenvolvimento
11.
Zygote ; 27(1): 49-53, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30714556

RESUMO

SummaryIn eutherian mammals, the placenta plays a critical role in embryo development by supplying nutrients and hormones and mediating interaction with the mother. To establish the fine connection between mother and embryo, the placenta needs to be formed normally, but the mechanism of placental differentiation is not fully understood. We previously revealed that mouse prolyl oligopeptidase (POP) plays a role in trophoblast stem cell (TSC) differentiation into two placental cell types, spongiotrophoblasts (SpT) and trophoblast giant cells. Here, we focused on SpT differentiation and attempted to elucidate a molecular mechanism. For Ascl2, Arnt, and Egfr genes that are indispensable for SpT formation, we found that a POP-specific inhibitor, SUAM-14746, significantly decreased Ascl2 expression, which was consistent with a significant decrease in expression of Flt1, a gene downstream of Ascl2. Although this downregulation was unlikely to be mediated by the PI3K-Akt pathway, our results indicated that POP controls TSC differentiation into SpT by regulating the Ascl2 gene.


Assuntos
Placenta/citologia , Serina Endopeptidases/genética , Trofoblastos/citologia , Animais , Translocador Nuclear Receptor Aril Hidrocarboneto/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Diferenciação Celular/genética , Receptores ErbB/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Camundongos , Gravidez , Prolina/análogos & derivados , Prolina/farmacologia , Serina Endopeptidases/metabolismo , Inibidores de Serino Proteinase/farmacologia , Tiazolidinas/farmacologia , Trofoblastos/fisiologia , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/genética
12.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1106-1107: 35-42, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30639948

RESUMO

Qiangshen tablet, an important prescription consisting of 14 kinds of Chinese herbal medicines, has been used for decades to treat kidney yang deficiency syndrome (KYDS) in China. Qiangshen tablet has been recorded in ChP (2015 edition) and possesses the effect of strengthening yang, invigorating qi and tonifying kidneys. In this research, a simple, reliable and specific method was established for simultaneous determination of stachydrine, psoralen, isopsoralen, morroniside, paeoniflorin and loganin in normal and KYDS rat plasma after intragastric administration of a Qiangshen tablet suspension by UPLC-MS/MS. Protein precipitation (PP) by acetonitrile and liquid-liquid extraction (LLE) by ethyl acetate - n-butanol (1: 1, v/v) were used for pretreatment of plasma samples. Chromatographic separation of two IS (Internal Standard) and six analytes was achieved using an ACQUITY UPLC® BEH C18 column (2.1 × 100 mm, 1.7 µm). The mobile phase consisted of 0.1% formic acid aqueous solution (solvent A) and acetonitrile (solvent B) with a gradient scheme. Multiple reaction monitoring (MRM) mode with positive and negative ion source switching was applied to perform the mass spectrometric analyses. This method has been validated with good linearity (r ≥ 0.9942) and acceptable precision and accuracy (RSD ≤ 11%, RE from -4.8% to 7.7%). The mean recovery values of the analytes and IS were all ≥68.28%, and the matrix effects ranged from 94.4% to 101.7%. The stability of the IS and analytes was measured throughout the experiment. The results showed significant differences between the pharmacokinetic traits of the analytes in the normal and KYDS groups, suggesting that pharmacokinetic procedures involving these analytes could be modified in cases of KYDS.


Assuntos
Monitoramento de Medicamentos/métodos , Medicamentos de Ervas Chinesas , Deficiência da Energia Yang/tratamento farmacológico , Animais , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/farmacocinética , Ficusina/sangue , Furocumarinas/sangue , Glucosídeos/sangue , Glicosídeos/sangue , Iridoides/sangue , Masculino , Metaboloma , Monoterpenos/sangue , Prolina/análogos & derivados , Prolina/sangue , Ratos , Ratos Sprague-Dawley , Comprimidos/farmacocinética , Espectrometria de Massas em Tandem
13.
Cell Biol Int ; 43(3): 279-289, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30632646

RESUMO

Long-standing untreated hyperuricemia could lead to gout. Several recent studies have demonstrated a significant decrease of serum urate during acute gout attack, which is an aseptic inflammation process focusing on IL-1ß. However, how IL-1ß, by itself, alters the expression and the functional activity of urate transporters in renal tubular epithelial cells is still unclear. Herein, we revealed that IL-1ß could attenuate the mRNA and protein levels of ABCG2, a major urate efflux pump, in HK-2 cells by real-time PCR and Western-blot assays. Moreover, using an ABCG2 specific inhibitor and a new sensitive and specific detection system, it was found that IL-1ß also reduced the ABCG2 transporter activities. Incubation with specific inhibitors of the NF-κB pathway partly dampened the inhibitory effect of IL-1ß on ABCG2, indicating that IL-1ß reduced the ABCG2 expression partially through the NF-ĸB pathway. Furthermore, the decreased expression of PDZK1 induced by IL-1ß, which is dependent on the NF-κB pathway, could account for the imbalance between the functions and expressions of ABCG2 on this status. These findings demonstrated a new role for IL-1ß, whereby it leads to the inhibition of ABCG2 in renal tubular epithelial cells; this new role probably does not encompass its involvement in the process of renal urate excretion mediated by inflammation. Therefore, other regulation mechanisms of urate reabsorption in renal tubular epithelial cells deserve to be examined in further studies.


Assuntos
Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Proteínas de Transporte/metabolismo , Interleucina-1beta/farmacologia , NF-kappa B/metabolismo , Proteínas de Neoplasias/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Sequência de Bases , Transporte Biológico/efeitos dos fármacos , Linhagem Celular , Humanos , Proteínas de Membrana , Proteínas de Neoplasias/genética , Nitrilos/farmacologia , Polimorfismo de Nucleotídeo Único/genética , Prolina/análogos & derivados , Prolina/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Sulfonas/farmacologia , Tiocarbamatos/farmacologia , Fatores de Tempo , Ácido Úrico/metabolismo
14.
ACS Chem Biol ; 14(2): 296-303, 2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-30620575

RESUMO

The interplay between the activities of lytic transglycosylases (LTs) and penicillin-binding proteins (PBPs) is critical for the health of the bacterial cell wall. Bulgecin A (a natural-product inhibitor of LTs) potentiates the activity of ß-lactam antibiotics (inhibitors of PBPs), underscoring this intimate mechanistic interdependence. Bulgecin A in the presence of an appropriate ß-lactam causes bulge deformation due to the formation of aberrant peptidoglycan at the division site of the bacterium. As Pseudomonas aeruginosa, a nefarious human pathogen, has 11 LT paralogs, the answer as to which LT activity correlates with ß-lactam potentiation is important and is currently unknown. Growth of P. aeruginosa PAO1 strains harboring individual transposon-insertion mutants at each of the 11 genes for LTs, in the presence of the ß-lactam antibiotic ceftazidime or meropenem, implicated the gene products of slt, mltD, and mltG (of the 11), in bulge formation and potentiation. Hence, the respective enzymes would be the targets of inhibition by bulgecin A, which was indeed documented. We further demonstrated by imaging in real time and by SEM that cell lysis occurs by the structural failure of this bulge. Upon removal of the ß-lactam antibiotic prior to lysis, P. aeruginosa experiences delayed recovery from the elongation and bulge phenotype in the presence of bulgecin A. These observations argue for a collaborative role for the target LTs in the repair of the aberrant cell wall, the absence of activities of which in the presence of bulgecin A results in potentiation of the ß-lactam antibiotic.


Assuntos
Acetilglucosamina/análogos & derivados , Antibacterianos/farmacologia , Proteínas de Bactérias/metabolismo , Prolina/análogos & derivados , Pseudomonas aeruginosa/efeitos dos fármacos , beta-Lactamas/farmacologia , Acetilglucosamina/farmacologia , Testes de Sensibilidade Microbiana , Prolina/farmacologia , Pseudomonas aeruginosa/crescimento & desenvolvimento , Pseudomonas aeruginosa/metabolismo , Pseudomonas aeruginosa/fisiologia
15.
Int J Mol Sci ; 20(3)2019 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-30678338

RESUMO

Gliomas are the most aggressive adult primary brain tumors. Expression of inducible Nitric Oxide Synthase has been reported as a hallmark of chemoresistance in gliomas and several studies have reported that inhibition of inducible Nitric Oxide Synthase could be related to a decreased proliferation of glioma cells. The present work was to analyze the molecular effects of the acetamidine derivative compound 39 (formally CM544, N-(3-{[(1-iminioethyl)amino]methyl}benzyl) prolinamide dihydrochloride), a newly synthetized iNOS inhibitor, in a C6 rat glioma cell model. There is evidence of CM544 selective binding to the iNOS, an event that triggers the accumulation of ROS/RNS, the expression of Nrf-2 and the phosphorylation of MAPKs after 3 h of treatment. In the long run, CM544 leads to the dephosphorylation of p38 and to a massive cleavage of PARP-1, confirming the block of C6 rat glioma cell proliferation in the G1/S checkpoint and the occurrence of necrotic cell death.


Assuntos
Amidinas/farmacologia , Antineoplásicos/farmacologia , Neoplasias Encefálicas/metabolismo , Proliferação de Células/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Glioma/metabolismo , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Prolina/análogos & derivados , Animais , Linhagem Celular Tumoral , Poli(ADP-Ribose) Polimerase-1/metabolismo , Prolina/farmacologia , Proteólise , Ratos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
16.
Nat Prod Res ; 33(9): 1322-1328, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-29781300

RESUMO

Capparis spinosa L. is a perennial plant typical of the Mediterranean flora and a multipurpose plant used for curing various human ailments. Quaternary ammonium compounds (QACs), as constituents of Capparaceae, play important roles in protecting against abiotic stress. Aim of this work was to determine QACs in root and leaves of caper from two proveniences. The presence of stachydrine, choline, glycine betaine and homo-stachydrine has been confirmed by high resolution MS, while 1H NMR was applied to quantify the main QACs in the aqueous extracts. Stachydrine was quantified at 20.2 mg/g and 32.3 mg/g on dry leaves from South of Italy and Saudi Arabia, respectively, while a minor content was in dry roots (from 10.4 to 12.5 mg/g). Choline was considerably lower both in leaves and roots (from 0.3 to 1.2 mg/g). To our knowledge, this is the first report on the determination of QACs both in root and leaves of C. spinosa.


Assuntos
Capparis/química , Folhas de Planta/química , Raízes de Plantas/química , Compostos de Amônio Quaternário/análise , Colina/análise , Cromatografia Líquida de Alta Pressão , Humanos , Itália , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Extratos Vegetais/análise , Extratos Vegetais/química , Plantas Medicinais/química , Prolina/análogos & derivados , Prolina/análise , Compostos de Amônio Quaternário/química , Arábia Saudita
17.
Basic Clin Pharmacol Toxicol ; 124(1): 40-49, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29998529

RESUMO

Prolyl oligopeptidase (PREP) is an abundant peptidase in the brain and periphery, but its physiological functions are still largely unknown. Recent findings point to a role for PREP in inflammatory processes. This study assessed the cellular and extracellular PREP activities in cultures of mouse primary cortical neurons, microglial cells and astrocytes, and immortalized microglial BV-2 cells under neuroinflammatory conditions induced by lipopolysaccharide (LPS) and interferon gamma (IFNγ). Furthermore, we evaluated the neuroprotective effect of a specific PREP inhibitor, KYP-2047, in a neuroinflammation model based on a coculture of primary cortical neurons and activated BV-2 cells. The inflammatory insult reduced intracellular and increased extracellular PREP activity specifically in microglial cells, suggesting that activated microglia excretes active PREP. A targeted proteomics approach revealed up-regulation in PREP protein levels in BV-2 cell growth medium but down-regulation in crude membrane-bound PREP after LPS+IFNγ. In the coculture of BV-2 cells and primary neurons, an increase in extracellular PREP activity was also detected after inflammation. KYP-2047 (10 µmol/L) significantly protected neurons against microglial toxicity and reduced the levels of the pro-inflammatory cytokine tumour necrosis factor alpha. In conclusion, these data point to an extracellular role for microglial PREP in the inflammatory process. Inhibition of PREP during neuroinflammation is a potential target for neuroprotection. Thus, PREP inhibitors may offer a novel therapeutic approach for the treatment of neurodegenerative disorders with an inflammatory component including Parkinson's and Alzheimer's diseases.


Assuntos
Microglia/metabolismo , Inflamação Neurogênica/tratamento farmacológico , Prolina/análogos & derivados , Serina Endopeptidases/metabolismo , Inibidores de Serino Proteinase/farmacologia , Animais , Animais Recém-Nascidos , Membrana Celular/metabolismo , Córtex Cerebral/citologia , Técnicas de Cocultura , Meios de Cultura/metabolismo , Modelos Animais de Doenças , Regulação para Baixo , Embrião de Mamíferos , Feminino , Humanos , Lipopolissacarídeos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microglia/citologia , Microglia/imunologia , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/imunologia , Inflamação Neurogênica/imunologia , Neurônios , Neuroproteção/efeitos dos fármacos , Cultura Primária de Células , Prolina/farmacologia , Prolina/uso terapêutico , Serina Endopeptidases/imunologia , Inibidores de Serino Proteinase/uso terapêutico , Regulação para Cima
18.
Toxicol Lett ; 301: 17-23, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30408508

RESUMO

Perfluorooctane sulfonyl fluoride (PFOSF) has been defined as persistent organic pollutant in the Stockholm Convention in 2009. Currently PFOSF and its substitutes (structural analogues in which octyl group is substituted for other aliphatic chains) are still scarcely studied. HSA is a main carrier for drugs in blood, and the influence of exogenous compounds including pollutants on HSA is of particular interest. In this work, the binding sites of HSA to Perfluoroalkane sulfonyl fluoride (PFASFs) were determined by fluorescence technique. The results demonstrated that PFASFs competitively bind to HSA at Sudlow's site I against warfarin and at Sudlow's site II against dansyl-proline and the related association constants were determined. The association constants of PFOSF, perfluorohexane sulfonyl fluoride (PFHSF) and perfluorobutane sulfonyl fluoride (PFBSF) were determined to be 2.59 × 10-3 µM-1, 4.65 × 10-3 µM-1 and 2.85 × 10-3 µM-1 at Sudlow's site I and 8.68 × 10-4 µM-1, 3.43 × 10-2 µM-1 and 1.92 × 10-2 µM-1 at Sudlow's site II, respectively. The results showed that PFASFs can bind tightly to HSA and thus migrate to all parts of the body through vascular system. Non-covalent interaction between HSA and PFASFs was confirmed with tryptic digestion experiment. The mass spectra results indicated that other binding sites of HSA are also involved in the binding of PFHSF and PFBSF. The total binding numbers of PFOSF, PFHSF and PFBSF on HSA are 2, 6 and 3, respectively.


Assuntos
Fluorcarbonetos/metabolismo , Albumina Sérica Humana/metabolismo , Ácidos Sulfínicos/metabolismo , Sítios de Ligação , Compostos de Dansil/metabolismo , Interações de Medicamentos , Humanos , Prolina/análogos & derivados , Prolina/metabolismo , Varfarina/metabolismo
19.
Rev Soc Bras Med Trop ; 51(6): 731-736, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30517525

RESUMO

INTRODUCTION: Chronic hepatitis C is a leading cause of liver disease. Infection triggers an immediate immune response in the host that is mediated by humoral/cellular mechanisms. T cells respond to infection via secretion of cytokines, which inhibit or stimulate one another, leading to cytokine imbalance and ultimately affecting treatment. Studies using interferon (IFN) and ribavirin (RBV) showed that TCD8+ cells and cytokine levels are associated with sustainable virological response (SVR). However, studies that investigated the effects of triple therapy (TT) are limited. METHODS: The study included hepatitis C virus (HCV)+ RNA, naives, genotype 1, ≥18 years, and advanced fibrosis (F≥3) patients. Samples were collected at baseline and after 12 weeks (W12) of TT. Six cytokines were analyzed by flow cytometry. RESULTS: Of 31 patients, four were excluded (two deaths, one interrupted TT, and one F2 patient). Of the 27 remaining patients, 21 (78%) were cirrhotic. SVR was achieved in 63% of the patients. The patients had a mean age of 55.11 ± 10.03 years. Analyses at baseline showed that the chemokine CCL5/Regulated on Activation, Normal T Cell Expressed and Secreted (RANTES) (p=0.04) and interleukin (IL)-6 (p=0.02), which was associated with SVR. RANTES (p=0.04) and IL-8 (p=0.01) levels were associated with SVR at W12. CONCLUSIONS: Similar to patterns observed during double therapy, IL-6, IL-8, and RANTES levels were associated with SVR in TT, indicating the potential role of interferon in immune response to hepatitis C virus.


Assuntos
Antivirais/administração & dosagem , Citocinas/sangue , Hepatite C Crônica/tratamento farmacológico , Oligopeptídeos/administração & dosagem , Prolina/análogos & derivados , Quimioterapia Combinada , Feminino , Citometria de Fluxo , Genótipo , Hepatite C Crônica/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Prolina/administração & dosagem , Estudos Prospectivos , Resultado do Tratamento , Carga Viral
20.
BMC Biochem ; 19(1): 13, 2018 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-30587127

RESUMO

BACKGROUND: Sepsis is a severe condition characterised by the body's systemic inflammatory response to infection. The specific sepsis-related biomarkers should be used in clinical diagnosis, therapeutic response monitoring, rational use of antibiotics, and prognosis (risk stratification), etc. RESULTS: In this study, we investigated the expression level of Decoy Receptor 3 (DcR3) and the mechanism of high expression in sepsis patients. Septic cell model experiments were performed by treating human umbilical vein endothelial cells (HUVECs) and Jurkat cells with lipopolysaccharide (LPS), lipoteichoic acid (LTA) and zymosan, respectively. SP600125, SB203580 and ammonium pyrrolidinedithiocarbamate (PDTC) were used to inhibit JNK1/2, p38MAPK and NF-κB signalling pathways in septic cell model, respectively. These results showed that DcR3 levels were higher in sepsis group than control. DcR3 mRNA and protein levels in HUVECs were increased following treatment with LPS, LTA and zymosan, and also increased in Jurkat cells treated by LPS, but not by LTA or zymosan. When HUVECs were treated with the NF-κB inhibitor PDTC, DcR3 expression was decreased compared with controls. However, SP600125 and SB203580 had no effect on DcR3 mRNA or protein levels. CONCLUSIONS: The results indicated that DcR3 secretion proceeded through the NF-κB signalling pathway in HUVECs.


Assuntos
Lipopolissacarídeos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Antracenos/farmacologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Imidazóis/farmacologia , Células Jurkat , NF-kappa B/metabolismo , Prolina/análogos & derivados , Prolina/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Piridinas/farmacologia , Membro 6b de Receptores do Fator de Necrose Tumoral/metabolismo , Ácidos Teicoicos/farmacologia , Tiocarbamatos/farmacologia , Zimosan/farmacologia
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