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1.
Ann Otol Rhinol Laryngol ; 129(3): 245-255, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31646875

RESUMO

OBJECTIVES: Diesel exhaust particles (DEP)s are notorious ambient pollutants composed of a complex mixture of a carbon core and diverse chemical irritants. Several studies have demonstrated significant relationships between DEP exposure and serious nasal inflammatory response in vitro, but available information regarding underlying networks in terms of gene expression changes has not sufficiently explained potential mechanisms of DEP-induced nasal damage, especially in vivo. METHODS: In the present study, we identified DEP-induced gene expression profiles under short-term and long-term exposure, and identified signaling pathways based on microarray data for understanding effects of DEP exposure in the mouse nasal cavity. RESULTS: Alteration in gene expression due to DEP exposure provokes an imbalance of the immune system via dysregulated inflammatory markers, predicted to disrupt protective responses against harmful exogenous substances in the body. Several candidate markers were identified after validation using qRT-PCR, including S100A9, CAMP, IL20, and S100A8. CONCLUSIONS: Although further mechanistic studies are required for verifying the utility of the potential biomarkers suggested by the present study, our in vivo results may provide meaningful suggestions for understanding the complex cellular signaling pathways involved in DEP-induced nasal damages.


Assuntos
Expressão Gênica , Rinite/induzido quimicamente , Emissões de Veículos/toxicidade , Animais , Peptídeos Catiônicos Antimicrobianos/genética , Peptídeos Catiônicos Antimicrobianos/metabolismo , Antígeno B7-1/genética , Antígeno B7-1/metabolismo , Biomarcadores/metabolismo , Calgranulina A/genética , Calgranulina A/metabolismo , Calgranulina B/genética , Calgranulina B/metabolismo , Interleucinas/genética , Interleucinas/metabolismo , Camundongos Endogâmicos BALB C , Modelos Animais , Testes de Provocação Nasal , Análise de Sequência com Séries de Oligonucleotídeos , RNA/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Rinite/metabolismo , Transdução de Sinais , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/genética , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/metabolismo
2.
Chem Biol Interact ; 315: 108904, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31758921

RESUMO

Epinecidin-1 (epi) was identified from orange-spotted grouper (Epinephelus coioides) and exhibits diverse biological activities. The aims of this study were to investigate how the distribution of positively charged amino acid residues affects epi-mediated cytotoxicity and to examine the molecular mechanism underlying epi-induced cytotoxicity in U87MG human glioblastoma cells. MTS/PMS and trypan blue exclusion assay were used to measure cell viability. Necrotic cell death was confirmed by detecting cyclophilin A release and propidium iodide incorporation. DNA damage was evaluated by measuring phosphorylated H2AX. Intracellular reactive oxygen species (ROS) were analyzed by flow cytometry using dihydroergotamine. Mitochondrial membrane potential was detected by flow cytometry using tetramethylrhodamine, ethyl ester. Overall, we found that epi caused cytotoxicity in U87MG cells by inducing DNA damage and necrosis through mitochondrial hyperpolarization and subsequent ROS production. The proper folding of epi into an α-helical structure was essential for epi-mediated anti-glioblastoma effects. In addition, NFκB signaling was activated in U87MG cells after exposure to epi. Suppression of NFκB further enhanced epi-induced cytotoxicity, ROS generation and DNA damage, indicating that NFκB may play a protective role in epi-induced cytotoxicity. Our findings may be useful for the design and improvement of antimicrobial peptides with anti-cancer activity.


Assuntos
Aminoácidos/metabolismo , Peptídeos Catiônicos Antimicrobianos/metabolismo , Peptídeos Catiônicos Antimicrobianos/farmacologia , Apoptose/efeitos dos fármacos , Proteínas de Peixes/metabolismo , Proteínas de Peixes/farmacologia , Glioblastoma/tratamento farmacológico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Glioblastoma/metabolismo , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , NF-kappa B/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
3.
Protein Pept Lett ; 27(1): 60-66, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31362652

RESUMO

BACKGROUND: Cathelicidins are a family of Host Defense Peptides (HDPs), that play an important role in the innate immune response. They exert both broad-spectrum antimicrobial activity against pathogens, and strong immunomodulatory functions that affect the response of innate and adaptive immune cells. OBJECTIVE: The aim of this study was to investigate immunomodulation by the chicken cathelicidin CATH-2 and compare its activities to those of the human cathelicidin LL-37. METHODS: Chicken macrophages and chicken monocytes were incubated with cathelicidins. Activation of immune cells was determined by measuring surface markers Mannose Receptor Ctype 1 (MRC1) and MHC-II. Cytokine production was measured by qPCR and nitric oxide production was determined using the Griess assay. Finally, the effect of cathelicidins on phagocytosis was measured using carboxylate-modified polystyrene latex beads. RESULTS: CATH-2 and its all-D enantiomer D-CATH-2 increased MRC1 and MHC-II expression, markers for antigen presentation, on primary chicken monocytes, whereas LL-37 did not. D-CATH- 2 also increased the MRC1 and MHC-II expression if a chicken macrophage cell line (HD11 cells) was used. In addition, LPS-induced NO production by HD11 cells was inhibited by CATH-2 and D-CATH-2. CONCLUSION: These results are a clear indication that CATH-2 (and D-CATH-2) affect the activation state of monocytes and macrophages, which leads to optimization of the innate immune response and enhancement of the adaptive immune response.


Assuntos
Biomarcadores/metabolismo , Catelicidinas/metabolismo , Macrófagos/metabolismo , Monócitos/metabolismo , Sequência de Aminoácidos , Animais , Apresentação do Antígeno/efeitos dos fármacos , Peptídeos Catiônicos Antimicrobianos/metabolismo , Linhagem Celular , Galinhas , Citocinas/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe II/metabolismo , Humanos , Imunidade Inata/efeitos dos fármacos , Imunomodulação/efeitos dos fármacos , Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Lectinas de Ligação a Manose/genética , Lectinas de Ligação a Manose/metabolismo , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo
4.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 31(10): 1224-1230, 2019 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-31771719

RESUMO

OBJECTIVE: To evaluate the application of heparin-binding protein (HBP) in diagnosis of sepsis in adult patients. METHODS: An extensive search for the Chinese and English literatures from the PubMed, Embase, the Cochrane Library, Wanfang data, CNKI and VIP up to July 2019 was performed. The articles regarding HBP for the diagnosing of sepsis in adult patients were enrolled. Two researchers independently extracted related literature. The quality of the studies was assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. Meta-Disc 1.4 and STATA 12.0 were used for Meta-analysis. The pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR) were calculated. Summary receiver operating characteristic (SROC) curves and area under the curve (AUC) were used to evaluate the diagnostic performance of HBP for sepsis. Deek funnel plot was used to detect publication bias. RESULTS: A total of 10 studies with 1 884 patients were included in this Meta-analysis. The quality of the literature was relatively moderate. HBP in plasma were detected by enzyme linked immunosorbent assay (ELISA) in all studies. The studies showed substantial heterogeneity, and random effect model was used for Meta-analysis. The pooled sensitivity, specificity, PLR, NLR, and DOR were 0.80 [95% confidence interval (95%CI) was 0.77-0.83], 0.80 (95%CI was 0.78-0.82), 3.96 (95%CI was 2.45-6.41), 0.28 (95%CI was 0.20-0.39) and 14.63 (95%CI was 6.83-31.30) respectively. The pooled AUC was 0.86 and the Cochran-Q was 0.79. To explore the potential sources of heterogeneity, subgroup analyses were performed based on the severity of the disease, diagnostic criteria and region. However, the results indicated that no methodological covariates affected the diagnostic accuracy of HBP, indicating that there was still unexplained heterogeneity. In addition, the sensitivity analysis by removing individual studies were performed. No outlier study was identified and the results were relatively stable and reliable. Deek funnel plot showed little publication bias. CONCLUSIONS: There is preferable value of HBP for diagnosis of sepsis in adult patients. However, it needs to be further confirmed by large multicenter studies.


Assuntos
Peptídeos Catiônicos Antimicrobianos/metabolismo , Proteínas Sanguíneas/metabolismo , Sepse/diagnóstico , Adulto , Humanos , Sensibilidade e Especificidade , Sepse/metabolismo
5.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 31(9): 1083-1086, 2019 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-31657329

RESUMO

OBJECTIVE: To discuss the clinical significance of antibacterial peptide LL-37 in the early diagnosis of patients with sepsis in emergency department. METHODS: Forty patients diagnosed with sepsis in the emergency department of the Affiliated Hospital of Zunyi Medical College from December 2017 to March 2018 were enrolled as sepsis group. Twenty healthy volunteers were enrolled contemporaneously in our hospital at medical center as healthy control group. Peripheral blood was collected immediately after diagnosis in sepsis group or during physical examination in healthy control group. The expression of antibacterial peptide LL-37 was determined by enzyme-linked immunosorbent assay (ELISA). Meanwhile, serum procalcitonin (PCT) and C-reactive protein (CRP) levels were determined. The differences in antibacterial peptide LL-37, PCT and CRP levels between the two groups were compared. Pearson correlation method was used to analyze the correlation between antibacterial peptide LL-37, PCT and CRP. Receiver operating characteristic (ROC) curve was drawn, and the early individually or jointly diagnostic value of each detected index for sepsis was analyzed. RESULTS: The levels of antimicrobial peptide LL-37, PCT and CRP in peripheral blood of sepsis group were significantly higher than those of healthy control group [LL-37 (µg/L): 1.34±0.69 vs. 0.10±0.06, PCT (µg/L): 46.67±39.51 vs. 0.03±0.02, CRP (mg/L): 129.68±49.83 vs. 3.16±2.85], with statistically significant differences (all P < 0.05). Pearson correlation analysis showed that the expression of antimicrobial peptide LL-37 was positively correlated with PCT and CRP levels (r1 = 0.835, r2 = 0.932, both P < 0.01). ROC curve analysis showed that the area under ROC curve (AUC) of LL-37, PCT and CRP for early diagnosis of sepsis was 0.885, 0.963 and 0.983, respectively, and the AUC of combined diagnosis of the three parameters was as high as 0.994, indicating that the value of combined diagnosis of sepsis was greater than that of single diagnosis; when the combined prediction probability of the three parameters was 0.92, the sensitivity was 97.5%, and the specificity was 95.0%. CONCLUSIONS: Antibacterial peptide LL-37 has certain clinical value in early diagnosis of patients with sepsis, which can be used as early routine monitoring indicators for patients with early sepsis when combined with PCT and CRP.


Assuntos
Peptídeos Catiônicos Antimicrobianos/metabolismo , Calcitonina , Sepse/diagnóstico , Proteína C-Reativa , Peptídeo Relacionado com Gene de Calcitonina , Diagnóstico Precoce , Serviço Hospitalar de Emergência , Humanos , Precursores de Proteínas , Curva ROC , Sepse/metabolismo
6.
Int J Mol Sci ; 20(19)2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31581426

RESUMO

The advent of multidrug resistance among pathogenic bacteria has attracted great attention worldwide. As a response to this growing challenge, diverse studies have focused on the development of novel anti-infective therapies, including antimicrobial peptides (AMPs). The biological properties of this class of antimicrobials have been thoroughly investigated, and membranolytic activities are the most reported mechanisms by which AMPs kill bacteria. Nevertheless, an increasing number of works have pointed to a different direction, in which AMPs are seen to be capable of displaying non-lytic modes of action by internalizing bacterial cells. In this context, this review focused on the description of the in vitro and in vivo antibacterial and antibiofilm activities of non-lytic AMPs, including indolicidin, buforin II PR-39, bactenecins, apidaecin, and drosocin, also shedding light on how AMPs interact with and further translocate through bacterial membranes to act on intracellular targets, including DNA, RNA, cell wall and protein synthesis.


Assuntos
Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Bactérias/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Animais , Peptídeos Catiônicos Antimicrobianos/metabolismo , Bactérias/metabolismo , Glicopeptídeos/metabolismo , Insetos , Biossíntese de Proteínas
7.
Nutrients ; 11(9)2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31500220

RESUMO

In chronic obstructive pulmonary disease (COPD), the bronchial epithelium is the first immune barrier that is triggered by cigarette smoke. Although vitamin D (vitD) has proven anti-inflammatory and antimicrobial effects in alveolar macrophages, little is known about the direct role of vitD on cigarette smoke-exposed bronchial epithelial cells. We examined the effects of vitD on a human bronchial epithelial cell line (16HBE) and on air-liquid culture of primary bronchial epithelial cells (PBEC) of COPD patients and controls exposed for 24 h to cigarette smoke extract (CSE). VitD decreased CSE-induced IL-8 secretion by 16HBE cells, but not by PBEC. VitD significantly increased the expression of the antimicrobial peptide cathelicidin in 16HBE and PBEC of both COPD subjects and controls. VitD did not affect epithelial to mesenchymal transition or epithelial MMP-9 expression and was not able to restore impaired wound healing by CSE in 16HBE cells. VitD increased the expression of its own catabolic enzyme CYP24A1 thereby maintaining its negative feedback. In conclusion, vitD supplementation may potentially reduce infectious exacerbations in COPD by the upregulation of cathelicidin in the bronchial epithelium.


Assuntos
Brônquios/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Doença Pulmonar Obstrutiva Crônica/metabolismo , Fumaça/efeitos adversos , Produtos do Tabaco/efeitos adversos , Vitamina D/análogos & derivados , Idoso , Peptídeos Catiônicos Antimicrobianos/genética , Peptídeos Catiônicos Antimicrobianos/metabolismo , Brônquios/metabolismo , Brônquios/patologia , Estudos de Casos e Controles , Linhagem Celular , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Feminino , Humanos , Interleucina-8/metabolismo , Masculino , Doença Pulmonar Obstrutiva Crônica/genética , Doença Pulmonar Obstrutiva Crônica/patologia , Receptores de Calcitriol/agonistas , Receptores de Calcitriol/genética , Receptores de Calcitriol/metabolismo , Vitamina D/metabolismo , Vitamina D/farmacologia , Vitamina D3 24-Hidroxilase/genética , Vitamina D3 24-Hidroxilase/metabolismo
8.
Mar Drugs ; 17(9)2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31470685

RESUMO

Antimicrobial peptides (AMPs) are natural antibiotics produced by all living organisms. In metazoans, they act as host defense factors by eliminating microbial pathogens. But they also help to select the colonizing bacterial symbionts while coping with specific environmental challenges. Although many AMPs share common structural characteristics, for example having an overall size between 10-100 amino acids, a net positive charge, a γ-core motif, or a high content of cysteines, they greatly differ in coding sequences as a consequence of multiple parallel evolution in the face of pathogens. The majority of AMPs is specific of certain taxa or even typifying species. This is especially the case of annelids (ringed worms). Even in regions with extreme environmental conditions (polar, hydrothermal, abyssal, polluted, etc.), worms have colonized all habitats on Earth and dominated in biomass most of them while co-occurring with a large number and variety of bacteria. This review surveys the different structures and functions of AMPs that have been so far encountered in annelids and nematodes. It highlights the wide diversity of AMP primary structures and their originality that presumably mimics the highly diverse life styles and ecology of worms. From the unique system that represents marine annelids, we have studied the effect of abiotic pressures on the selection of AMPs and demonstrated the promising sources of antibiotics that they could constitute.


Assuntos
Antibacterianos/metabolismo , Peptídeos Catiônicos Antimicrobianos/metabolismo , Helmintos/metabolismo , Aminoácidos/metabolismo , Animais , Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Bactérias/efeitos dos fármacos , Ecossistema , Humanos
9.
Eur Cytokine Netw ; 30(2): 43-58, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31486403

RESUMO

The present study demonstrates that monocyte-derived dendritic cells (moDCs) produced in vitro using a GM-CSF and IFN-α differentiation protocol encompass a rare (∼5%) subpopulation of cells showing classical dendritic cell morphology and capable of natural internalization of extracellular self-DNA. We established that DEFB, HMGB1, LL-37 and RAGE antigens, which mediate the process of DNA internalization, are expressed on the surface of moDCs similar to plasmacytoid dendritic cells. However, in constrast to the latter subpopulation, these cells do not produce interleukin (IL)-37. Nonetheless, the process of DNA internalization was not in direct relation to the presence of the above antigens on the surface of these cells. Dendritic cells were sorted into total and non-DNA-internalizing populations and cytokine production was analyzed at 24-48 hours post-DNA treatment. We show that massive secretion of cytokines by dendritic cells is associated with the dsDNA-internalizing subpopulation. A total pool of IFN-moDCs secrete pro-inflammatory "first-wave" cytokines (IL-2, IL-6, IL-8, TNF-α) at both 24 and 48 hours time points. The anti-inflammatory cytokines IL-4 and IL-10 were found to be modestly induced, whereas GM-CSF, G-CSF, and IFN-γ production was strongly induced. Treatment of moDCs with dsDNA results in the up-regulated transcription of IFN-α, IFN-ß, IFN-γ, IL-8, IL-10, and VEGF by 6 hours. Combined dsDNA + chloroquine treatment has a synergistic effect on transcription of only one of the genes tested, with the pro-inflammatory cytokine IFN-ß displaying the strongest fold induction by 24 hours.


Assuntos
DNA/metabolismo , Células Dendríticas/citologia , Endocitose , Espaço Extracelular/metabolismo , Monócitos/citologia , Antígenos de Neoplasias/metabolismo , Peptídeos Catiônicos Antimicrobianos/metabolismo , Cloroquina/farmacologia , Citocinas/metabolismo , Sondas de DNA/metabolismo , Células Dendríticas/efeitos dos fármacos , Endocitose/efeitos dos fármacos , Feminino , Proteína HMGB1/metabolismo , Humanos , Interferons/farmacologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Monócitos/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Rodaminas/metabolismo , beta-Defensinas/metabolismo
10.
Fish Shellfish Immunol ; 93: 669-682, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31408728

RESUMO

Iron is an important mineral element for fish. In this study, we investigated the influences of dietary iron deficiency on intestinal immune function as well as underlying signaling of on-growing grass carp (Ctenopharyngodon idella). Fish were fed with six graded level of dietary iron for sixty days, and a fourteen days' challenge test under infection of Aeromonas hydrophila thereafter. Results showed that compared with optimal iron level, iron deficiency increased enteritis morbidity, decreased lysozyme (LZ) and acid phosphatase (ACP) activities, complement 3 (C3), C4 and immunoglobulin M (IgM) concentrations and down-regulated mRNA levels of hepcidin, liver expressed antimicrobial peptide 2A (LEAP-2A), LEAP-2B, Mucin2, ß-defensin-1, anti-inflammatory cytokines transforming growth factor ß1 (TGF-ß1), TGF-ß2, interleukin 4/13A (IL-4/13A), IL-4/13B, IL-10, IL-11 and IL-15, inhibitor of κBα (IκBα), target of rapamycin (TOR) and ribosomal protein S6 kinase 1 (S6K1), whereas up-regulated mRNA levels of pro-inflammatory cytokines IL-1ß, interferon γ2 (IFN-γ2), IL-8, IL-12p35, IL-12p40 and IL-17D, nuclear factor kappa B (NF-κB) p65, IκB kinases α (IKKα), IKKß and eIF4E-binding protein (4E-BP) in intestine of on-growing grass carp, indicating that iron deficiency impaired intestinal immune function of fish under infection of A. hydrophila. Besides, iron excess also increased enteritis morbidity and impaired immune function of fish under infection of A. hydrophila. In addition, the effect of ferrous fumarate on intestinal immune function of on-growing grass carp is more efficient than ferrous sulfate. Finally, based on ability against enteritis, LZ activities in mid intestine and distal intestine, we recommended adding 83.37, 86.71 and 85.39 mg iron/kg into diet, respectively.


Assuntos
Carpas/imunologia , Doenças dos Peixes/imunologia , Proteínas de Peixes/metabolismo , Intestinos/imunologia , Ferro/deficiência , Transdução de Sinais/efeitos dos fármacos , Aeromonas hydrophila/fisiologia , Animais , Peptídeos Catiônicos Antimicrobianos/metabolismo , Citocinas/metabolismo , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/veterinária , Intestinos/efeitos dos fármacos , Ferro na Dieta/metabolismo , NF-kappa B/metabolismo , Distribuição Aleatória , Serina-Treonina Quinases TOR/metabolismo
11.
Res Microbiol ; 170(8): 399-406, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31401108

RESUMO

Microcins and bacteriocins are ribosomally-synthesized defence peptides produced by Gram-negative and -positive bacteria to target competitors in their niche. Some of them carry posttranslational modifications established by dedicated enzymes. To protect themselves from their own toxic peptides, bacteria use dedicated immunity proteins or expel the toxin using ATP-binding cassette (ABC) transporters. In this last case, this immunity function is associated to export of the antimicrobial peptide out of the producing cells for targeting their competitors. Here we review the characteristics of these ABC-exporters and the mechanisms they use that unexpectedly cover from high promiscuity to high specificity or ensure another function concomitantly.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Peptídeos Catiônicos Antimicrobianos/metabolismo , Bacteriocinas/metabolismo , Bactérias Gram-Negativas/metabolismo , Bactérias Gram-Positivas/metabolismo , Antibacterianos/metabolismo , Bacteriocinas/genética , Transporte Biológico/fisiologia , Farmacorresistência Bacteriana/fisiologia
12.
Insect Biochem Mol Biol ; 113: 103215, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31449847

RESUMO

In this study, two novel antibacterial peptide genes, termed lugensin A and B were identified and characterized from a rice sap-sucking hemipteran insect pest, the brown planthopper, Nilaparvata lugens. Lugensin gene expression was significantly induced by Gram-negative and Gram-positive bacterial stains under the regulation of a signal receptor, the long peptidoglycan recognition protein (PGRP-LC) in the IMD pathway. Knockdown of PGRP-LC by RNAi eliminated bacterium induced Lugensin gene expression. Lugensins had the apparent antibacterial activities against Escherichia coli K12, Bacillus subtilis and the rice bacterial brown stripe pathogen Acidovorax avenae subsp. avenae (Aaa) strain RS-1. Lugensins inhibited bacterial proliferation by disrupting the integrity of the bacterial membranes. Scanning electron microscopy revealed abnormal membrane morphology of the recombinant Lugensin-treated bacteria. Lugensins induced complete cell disruption of E. coli K12 and B. subtilis strains while formed the holes on the cell surface of Aaa RS-1 strain. Immunofluorescence showed that Lugensins localized in the cell membrane of E. coli K12 while accumulated in the cytosol of B. subtilis. Differently, Lugensins remained in both the cell membrane and the cytosol of Aaa RS-1 strain, suggesting different action modes of Lugensins to different microbes. This is the first report of the novel antibacterial peptides found in the rice sap-sucking hemipteran insect species.


Assuntos
Peptídeos Catiônicos Antimicrobianos/genética , Regulação da Expressão Gênica , Hemípteros/genética , Proteínas de Insetos/genética , Animais , Peptídeos Catiônicos Antimicrobianos/metabolismo , Peptídeos Catiônicos Antimicrobianos/farmacologia , Bacillus subtilis/efeitos dos fármacos , Comamonadaceae/efeitos dos fármacos , Escherichia coli K12/efeitos dos fármacos , Feminino , Hemípteros/crescimento & desenvolvimento , Hemípteros/metabolismo , Proteínas de Insetos/metabolismo , Proteínas de Insetos/farmacologia , Masculino , Ninfa/genética , Ninfa/metabolismo , Oócitos/metabolismo , Interferência de RNA
13.
Fish Shellfish Immunol ; 93: 1007-1017, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31449978

RESUMO

Pathogenic disease is a major factor affecting the aquaculture of the rockfish Sebastiscus marmoratus, an important commercial species inhabiting the nearshore waters of the Western Pacific Ocean. Antimicrobial peptides (AMPs), as critical components of innate immunity, have been considered as promising antibiotic substitutes. The aims of this study were 1) to identify major AMPs in the rockfish, 2) to assess their antimicrobial activity and 3) to evaluate their potential therapeutic application. Six AMPs were identified, Hepcidin 1, liver-expressed antimicrobial peptide 2 (LEAP-2), Piscidin, Moronecidin, NK-lysin and ß-defensin through analysis of the liver transcriptome of S. marmoratus. The transcriptional expression profiles of these AMPs were investigated by real-time quantitative PCR (RT-qPCR). These AMPs showed tissue-specific distribution patterns, and S. marmoratus displays a time-, dose- and tissue-dependent expression of AMPs in response to lipopolysaccharide (LPS) challenge. While the synthetic peptides of LEAP-2 and Moronecidin exerted broad-spectrum antimicrobial activity against important aquatic pathogens in vitro by directly disrupting microbial membrane, and no cytotoxicity against murine hepatic cells was observed at the effective concentrations from 5 µM to 40 µM. The existence of multiple AMPs and their distinct tissue distribution patterns and inducible expression patterns suggests a sophisticated, highly redundant, and multilevel network of antimicrobial defensive mechanisms of S. marmoratus. Therefore, S. marmoratus-derived AMPs appear to be potential therapeutic applications against pathogen infections in aquaculture.


Assuntos
Peptídeos Catiônicos Antimicrobianos/genética , Peptídeos Catiônicos Antimicrobianos/imunologia , Perciformes/genética , Perciformes/imunologia , Animais , Anti-Infecciosos/imunologia , Peptídeos Catiônicos Antimicrobianos/metabolismo , Linhagem Celular , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Proteínas de Peixes/metabolismo , Perfilação da Expressão Gênica/veterinária , Humanos , Lipopolissacarídeos/farmacologia , Camundongos , Perciformes/metabolismo
14.
J Mol Model ; 25(9): 260, 2019 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-31422479

RESUMO

In this research, we present a preliminary computational study of four Dermaseptin-related peptides from the skin exudate of the gliding tree frog Agalychnis spurrelli. Experimentally, the amino acid sequence of these peptides was elucidated through molecular cloning and tandem mass spectrometry and synthetic peptides were assayed against E. coli, S. aureus, and C. albicans to determine their antimicrobial properties. With the sequences on hand, a computational study of the structures was carried out, obtaining their physicochemical properties, secondary structure, and their similarity to other known peptides. A molecular docking study of these peptides was also performed against cell membrane and several enzymes are known to be vital for the organisms. Results showed that Dermaseptin-related peptides are α-helical cationic peptides with an isoelectric point above 9.70 and a positive charge of physiological pH. Introducing theses peptides in a database, it was determined that their identity compared with known peptides range from 36 to 82% meaning these four Dermaseptins are novel peptides. This preliminary study of molecular docking suggests the mechanism of action of this peptide is not given by the inhibition of essential enzymatic pathways, but by cell lysis. Graphical abstract.


Assuntos
Anti-Infecciosos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Simulação de Acoplamento Molecular , Proteínas de Anfíbios/química , Proteínas de Anfíbios/metabolismo , Proteínas de Anfíbios/farmacologia , Animais , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/metabolismo , Anuros , Candida albicans/efeitos dos fármacos , Clonagem Molecular , Escherichia coli/efeitos dos fármacos , Estrutura Secundária de Proteína , Staphylococcus aureus/efeitos dos fármacos
15.
Nutrients ; 11(8)2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31366090

RESUMO

Galacto-oligosaccharides (GOS), functional oligosaccharides with natural characteristics, are important active substances in milk that play an important role in the development of intestinal microbiota and the immune system of newborns. The intestinal maturation of piglets resembles that of human newborns and infants. Therefore, we used the newborn piglet model to study the effects of early-life GOS intervention. Six litters of neonatal piglets (10 piglets per litter) with the same average birth weight were divided into control (CON) and GOS (GOS) groups in each litter. Piglets in the GOS group were given 10 mL of GOS solution daily during the first week after birth, while piglets in the CON group were given the same dose of physiological saline orally. One pig per group from each litter was euthanized on day 8 and day 21. Results revealed that ileal microbiota composition was significantly enriched in Lactobacillus and unclassified Lactobacillaceae, and reduced in Clostridium sensu stricto on day 8 and day 21 after GOS intervention. Additionally, Escherichia significantly decreased on day 21 following the early-life GOS intervention. Moreover, the content of microbial metabolites, endocrine peptides, and the mRNA expression of anti-inflammatory cytokines and antimicrobial peptides increased in the GOS group. These findings provide guidelines for early prebiotic supplementation for lactating newborns.


Assuntos
Bactérias/classificação , Bactérias/metabolismo , Microbioma Gastrointestinal , Íleo/microbiologia , Oligossacarídeos/farmacologia , Suínos , Animais , Animais Recém-Nascidos , Peptídeos Catiônicos Antimicrobianos/genética , Peptídeos Catiônicos Antimicrobianos/metabolismo , Citocinas/genética , Citocinas/metabolismo , Ácidos Graxos Voláteis/química , Conteúdo Gastrointestinal/química , Conteúdo Gastrointestinal/microbiologia , Regulação da Expressão Gênica/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Ácido Láctico , Oligossacarídeos/administração & dosagem , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
16.
Molecules ; 24(16)2019 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-31426323

RESUMO

Dermaseptins belonging to a large family of cationic membrane-disruption antimicrobial peptides display extensive antibacterial and antiproliferative activities depending on a coil-to-helix transition and the specific structural parameters. Herein, a novel dermaseptin peptide named Der-PS4 was discovered from the skin secretion of the waxy monkey tree frog, Phyllomedusa sauvagii. The complementary DNA (cDNA)-encoding precursor was obtained relying on "shotgun" cloning, and afterwards, a mature peptide amino acid sequence was identified by reverse-phase high performance liquid chromatography (RP-HPLC) and MS/MS. Specimens were chemically synthesized and applied for further functional studies. Structural analysis demonstrated a higher α-helical content in the membrane-mimetic environment compared with that in the ammonium acetate/water circumstance. Der-PS4 displayed a broad spectrum of antimicrobial activities against tested pathogenic microorganisms, however, exhibiting slight membrane-damaging effectiveness towards horse red blood cells. Coincident with the inhibitory activities on pathogens, Der-PS4 also showed considerable biofilm eradicating impact. Also, Der-PS4 penetrated cell membrane in a relative short period under each minimum bactericidal concentration. In addition, Der-PS4 possessed antiproliferative capacity against five cancer cell lines, while presenting slight suppressing effect on human microvascular endothelial, HMEC-1. These findings provide a promising insight for the discovery and development of novel drugs from a natural source.


Assuntos
Proteínas de Anfíbios/farmacologia , Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Antineoplásicos/farmacologia , Proteínas Recombinantes/farmacologia , Sequência de Aminoácidos , Proteínas de Anfíbios/química , Proteínas de Anfíbios/isolamento & purificação , Proteínas de Anfíbios/metabolismo , Animais , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibacterianos/metabolismo , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/isolamento & purificação , Peptídeos Catiônicos Antimicrobianos/metabolismo , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antineoplásicos/metabolismo , Anuros/fisiologia , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Candida albicans/efeitos dos fármacos , Candida albicans/crescimento & desenvolvimento , Linhagem Celular Tumoral , Permeabilidade da Membrana Celular/efeitos dos fármacos , Clonagem Molecular/métodos , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Expressão Gênica , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/crescimento & desenvolvimento , Hemólise/efeitos dos fármacos , Cavalos , Humanos , Estrutura Secundária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Pele/química
17.
Nutrients ; 11(7)2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31336570

RESUMO

BACKGROUND: Although Lactobacillus casei Shirota (LcS) can benefit the immune status, the effects of LcS in the immune/inflammatory responses of marathon runners has never been evaluated. Therefore, here we evaluated the effect of daily ingestion of fermented milk containing or not LcS in the systemic and upper airway immune/inflammatory responses before and after a marathon. METHODS: Forty-two male marathon runners ingested a fermented milk containing 40 billion of LcS/day (LcS group, n = 20) or placebo (unfermented milk, n = 22) during 30 days pre-marathon. Immune/inflammatory parameters in nasal mucosa and serum, as well as concentrations of secretory IgA (SIgA) and antimicrobial peptides in saliva, were evaluated before and after fermented milk ingestion, immediately, 72 h, and 14 d post-marathon. RESULTS: Higher proinflammatory cytokine levels in serum and nasal mucosa, and also lower salivary levels of SIgA and antimicrobial peptides, were found immediately post-marathon in the placebo group compared to other time points and to LcS group. In opposite, higher anti-inflammatory levels and reduced neutrophil infiltration on nasal mucosa were found in the LcS group compared to other time points and to the placebo group. CONCLUSION: For the first time, it is shown that LcS is able to modulate the systemic and airways immune responses post-marathon.


Assuntos
Inflamação/prevenção & controle , Lactobacillus casei/classificação , Sistema Respiratório/imunologia , Corrida , Adulto , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/metabolismo , Produtos Fermentados do Leite , Citocinas/genética , Citocinas/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Imunoglobulina A/química , Masculino , Pessoa de Meia-Idade , Saliva/química
18.
J Pept Sci ; 25(9): e3201, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31309656

RESUMO

Targeted delivery of antitumor drugs is especially important for tumor therapy. Cell-penetrating peptides (CPPs) have been shown to be very effective drug carriers for tumor therapy. However, most CPPs lack tumor cell specificity. Here, we identified a highly efficient CPP, CAT, from the newly identified buffalo-derived cathelicidin family, which exhibits a preferential binding capacity for multiple tumor cell lines and delivers carried drug molecules into cells. CAT showed an approximately threefold to sixfold higher translocation efficiency than some reported cell-penetrating antimicrobial peptides, including the well-known classical CPP TAT. Moreover, the delivery efficiency of CAT was greater in a variety of tested tumor cells than in normal cells, especially for the human hepatoma cell line SMMC-7721, for which delivery was 7 times more efficient than the normal human embryonic lung cell line MRC-5, according to fluorescent labeling experiment results. CAT was conjugated to the Momordica charantia-derived type-I ribosome-inactivating protein MAP 30, and the cytotoxicity of the MAP 30-CAT fusion protein in the tumor cell line SMMC-7721 was significantly enhanced compared with that of the unconjugated MAP 30. The IC50 value of MAP 30-CAT was approximately 83 times lower than the IC50 value of the original MAP 30. Interestingly, the IC50 value of MAP 30 alone for MRC-5 was approximately twofold higher than the value for SMMC-7721, showing a small difference. However, when MAP 30 was conjugated to CAT, the difference in IC50 values between the two cell lines was significantly increased by 38-fold. The results of the flow cytometric detection of apoptosis revealed that the increase in cytotoxicity after CAT conjugation was mainly caused by the increased induction of apoptosis by the fusion protein. These results suggest that CAT, as a novel tumor-homing CPP, has great potential in drug delivery applications in vivo and will be beneficial to the development of tumor therapeutics.


Assuntos
Peptídeos Catiônicos Antimicrobianos/metabolismo , Antineoplásicos/farmacologia , Animais , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/isolamento & purificação , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Búfalos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Portadores de Fármacos/química , Portadores de Fármacos/isolamento & purificação , Portadores de Fármacos/metabolismo , Sistemas de Liberação de Medicamentos , Avaliação Pré-Clínica de Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Relação Estrutura-Atividade
19.
J Med Microbiol ; 68(8): 1253-1265, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31215857

RESUMO

INTRODUCTION: Acinetobacter baumannii is one of the most important nosocomial pathogens, mainly due to its ability to accumulate antibiotic-resistances and to persist in the hospital environment - characteristics related to biofilm production. It is well-known that A. baumannii is inhibited by the proline-rich peptide Bac7(1-35), but its putative effects at sub-MICs were never considered. AIMS: We examined the sub-MIC effect of Bac7(1-35) on the growth rate, resistance induction and some A. baumannii features linked to virulence. METHODOLOGY: Growth kinetics in the presence of sub-MICs of Bac7(1-35) were evaluated spectrophotometrically. Peptide uptake was quantified by cytometric analysis. The ability of Bac7(1-35) to interfere with biofilm production was investigated by the crystal violet method and confocal microscopy. Bacterial motility was observed at the interphase between a layer of a semi-solid medium and the polystyrene bottom of a Petri dish. The induction of resistance was evaluated after serial passages with sub-MICs of the peptide. RESULTS: Although the MIC of Bac7(1-35) was between 2-4 µM for all tested strains, its effect on the growth rate at sub-MICs was strain-dependent and correlated with the amount of peptide internalized by each strain. Sub-MICs of Bac7(1-35) induced a strongly strain-dependent effect on biofilm formation and reduced motility in almost all strains, but interestingly the peptide did not induce resistance. CONCLUSION: Bac7(1-35) is internalized into A. baumannii and is able to inhibit biofilm formation and bacterial motility, without inducing resistance. This study stresses the importance of considering possible effects that antimicrobials could have at sub-MICs, mimicking a common condition during antibiotic treatment.


Assuntos
Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/efeitos dos fármacos , Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Acinetobacter baumannii/isolamento & purificação , Acinetobacter baumannii/patogenicidade , Acinetobacter baumannii/fisiologia , Antibacterianos/química , Antibacterianos/metabolismo , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/metabolismo , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Relação Dose-Resposta a Droga , Farmacorresistência Bacteriana , Humanos , Locomoção/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Especificidade da Espécie , Virulência/efeitos dos fármacos
20.
Biochemistry (Mosc) ; 84(5): 464-478, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31234762

RESUMO

Bacteriocins are bacterial antimicrobial peptides that, unlike classical peptide antibiotics, are products of ribosomal synthesis and usually have a narrow spectrum of antibacterial activity against species closely related to the producers. Pediocin-like bacteriocins (PLBs) belong to the class IIa of the bacteriocins of Gram-positive bacteria. PLBs possess high activity against pathogenic bacteria from Listeria and Enterococcus genera. Molecular target for PLBs is a membrane protein complex - bacterial mannose-phosphotransferase. PLBs can be synthesized by components of symbiotic microflora and participate in the maintenance of homeostasis in various compartments of the digestive tract and on the surface of epithelial tissues contacting the external environment. PLBs could give a rise to a new group of antibiotics of narrow spectrum of activity.


Assuntos
Peptídeos Catiônicos Antimicrobianos/metabolismo , Bactérias Gram-Positivas/metabolismo , Pediocinas/metabolismo , Sequência de Aminoácidos , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/farmacologia , Enterococcus/efeitos dos fármacos , Bactérias Gram-Positivas/imunologia , Listeria/efeitos dos fármacos , Pediocinas/química , Pediocinas/farmacologia , Sistema Fosfotransferase de Açúcar do Fosfoenolpiruvato/química , Sistema Fosfotransferase de Açúcar do Fosfoenolpiruvato/metabolismo , Estrutura Secundária de Proteína , Alinhamento de Sequência
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