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1.
J Enzyme Inhib Med Chem ; 38(1): 36-50, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-36305289

RESUMO

The increasing resistance of fungi to conventional antifungal drugs has prompted worldwide the search for new compounds. In this work, we investigated the antifungal properties of acylated Temporin L derivatives, Pent-1B and Dec-1B, against Candida albicans, including the multidrug-resistant strains. Acylated peptides resulted to be active both on reference and clinical strains with MIC values ranging from 6.5 to 26 µM, and they did not show cytotoxicity on human keratinocytes. In addition, we also observed a synergistic or additive effect with voriconazole for peptides Dec-1B and Pent-1B through the checkerboard assay on voriconazole-resistant Candida strains. Moreover, fluorescence-based assays, NMR spectroscopy, and confocal microscopy elucidated a potential membrane-active mechanism, consisting of an initial electrostatic interaction of acylated peptides with fungal membrane, followed by aggregation and insertion into the lipid bilayer and causing membrane perturbation probably through a carpeting effect.


Assuntos
Antifúngicos , Candida albicans , Farmacorresistência Fúngica Múltipla , Humanos , Antifúngicos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Candida albicans/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Voriconazol/farmacologia
2.
Int J Mol Sci ; 24(11)2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37298727

RESUMO

Gut dysbiosis has been involved in the pathogenesis and progression of Parkinson's disease (PD), but the mechanisms through which gut microbiota (GM) exerts its influences deserve further study. Recently, we proposed a two-hit mouse model of PD in which ceftriaxone (CFX)-induced dysbiosis amplifies the neurodegenerative phenotype generated by striatal 6-hydroxydopamine (6-OHDA) injection in mice. Low GM diversity and the depletion of key gut colonizers and butyrate producers were the main signatures of GM alteration in this model. Here, we used the phylogenetic investigation of communities by reconstruction of unobserved states (PICRUSt2) to unravel candidate pathways of cell-to-cell communication associated with dual-hit mice and potentially involved in PD progression. We focused our analysis on short-chain fatty acids (SCFAs) metabolism and quorum sensing (QS) signaling. Based on linear discriminant analysis, combined with the effect size results, we found increased functions linked to pyruvate utilization and a depletion of acetate and butyrate production in 6-OHDA+CFX mice. The specific arrangement of QS signaling as a possible result of the disrupted GM structure was also observed. With this exploratory study, we suggested a scenario in which SCFAs metabolism and QS signaling might represent the effectors of gut dysbiosis potentially involved in the designation of the functional outcomes that contribute to the exacerbation of the neurodegenerative phenotype in the dual-hit animal model of PD.


Assuntos
Doença de Parkinson , Camundongos , Animais , Doença de Parkinson/metabolismo , Disbiose/metabolismo , Filogenia , Oxidopamina , Butiratos
3.
Molecules ; 27(20)2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36296701

RESUMO

Myrtaceae family is a continuous source of antimicrobial agents. In the search for novel antimicrobial agents against Staphylococcus species, bioactive fractions of Myrtus communis L., growing in the Sardinia island (Italy) have been investigated. Their phytochemical analysis led us to isolate and characterize four alkylphloroglucinol glycosides (1-4), three of them gallomyrtucommulones G-H (1,2), and myrtucommulonoside (4) isolated and characterized for the first time. The structures of the new and known compounds, endopreroxide G3 (5), myricetin-3-O-glycosides (6,7) were determined based on the spectroscopic evidence including 1D-/2D-NMR and HR-MS spectrometry. Enriched fractions as well as pure compounds were tested for their antimicrobial activity by broth micro-dilution assay against Staphylococcus epidermidis and S. aureus. Results reported herein demonstrated that gallomyrtucommulone G (1) showed a selective antimicrobial activity against both S. aureus strains (ATCC 29213 and 43300) until 16 µg/mL while gallomyrtucommulone D (3) showed the best growth inhibition value at 64 µg/mL.


Assuntos
Anti-Infecciosos , Myrtus , Myrtus/química , Floroglucinol/química , Staphylococcus aureus , Staphylococcus , Glicosídeos/farmacologia , Glicosídeos/análise , Testes de Sensibilidade Microbiana , Folhas de Planta/química , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/análise , Anti-Infecciosos/análise , Antibacterianos/química , Extratos Vegetais/química
4.
Epilepsia ; 62(2): 529-541, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33428780

RESUMO

OBJECTIVE: A large number of studies have highlighted the important role of the gut microbiota in the pathophysiology of neurological disorders, suggesting that its manipulation might serve as a treatment strategy. We hypothesized that the gut microbiota participates in absence seizure development and maintenance in the WAG/Rij rat model and tested this hypothesis by evaluating potential gut microbiota and intestinal alterations in the model, as well as measuring the impact of microbiota manipulation using fecal microbiota transplantation (FMT). METHODS: Initially, gut microbiota composition and intestinal histology of WAG/Rij rats (a well-recognized genetic model of absence epilepsy) were studied at 1, 4, and 8 months of age in comparison to nonepileptic Wistar rats. Subsequently, in a second set of experiments, at 6 months of age, untreated Wistar or WAG/Rij rats treated with ethosuximide (ETH) were used as gut microbiota donors for FMT in WAG/Rij rats, and electroencephalographic (EEG) recordings were obtained over 4 weeks. At the end of FMT, stool and gut samples were collected, absence seizures were measured on EEG recordings, and microbiota analysis and histopathological examinations were performed. RESULTS: Gut microbiota analysis showed differences in beta diversity and specific phylotypes at all ages considered and significant variances in the Bacteroidetes/Firmicutes ratio between Wistar and WAG/Rij rats. FMT, from both Wistar and ETH-treated WAG/Rij donors to WAG/Rij rats, significantly decreased the number and duration of seizures. Histological results indicated that WAG/Rij rats were characterized by intestinal villi disruption and inflammatory infiltrates already at 1 month of age, before seizure occurrence; FMT partially restored intestinal morphology while also significantly modifying gut microbiota and concomitantly reducing absence seizures. SIGNIFICANCE: Our results demonstrate for the first time that the gut microbiota is modified and contributes to seizure occurrence in a genetic animal model of absence epilepsy and that its manipulation may be a suitable therapeutic target for absence seizure management.


Assuntos
Antibacterianos/farmacologia , Anticonvulsivantes/farmacologia , Epilepsia Tipo Ausência/microbiologia , Transplante de Microbiota Fecal , Microbioma Gastrointestinal/efeitos dos fármacos , Microbioma Gastrointestinal/genética , Animais , Bacteroidetes , Butiratos/metabolismo , Colo/patologia , DNA Bacteriano/análise , DNA Ribossômico/genética , Modelos Animais de Doenças , Eletroencefalografia , Epilepsia Tipo Ausência/genética , Epilepsia Tipo Ausência/fisiopatologia , Epilepsia Tipo Ausência/terapia , Etossuximida/farmacologia , Ácidos Graxos Voláteis/metabolismo , Firmicutes , Motilidade Gastrointestinal , Haptoglobinas/metabolismo , Íleo/patologia , Propionatos/metabolismo , Precursores de Proteínas/metabolismo , Proteobactérias , Ratos , Ratos Wistar , Convulsões/genética , Convulsões/microbiologia , Convulsões/fisiopatologia
5.
Bioorg Med Chem Lett ; 30(17): 127413, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32700680

RESUMO

Herein we report the preparation of 3,4-dibenzylfurans and some oxidized derivatives with lignan backbone. The compounds were prepared using the Friedel-Crafts reaction with BF3 etherate as catalyst, demethylation with iodocyclohexane, acetylation and oxidation reactions. The antimicrobial activity was evaluated through their capacity to inhibit the growth of Gram positive and Gram negative bacteria, and of the yeast Candida albicans. Among ten products assayed four furans displayed a good antimicrobial activity against Staphylococcus aureus, S. epidermidis and C. albicans; on the contrary, none of the compounds were active against Pseudomonas aeruginosa. One of them inhibited the growth of S. aureus, S. epidermidis (biofilm producer strain) and C. albicans at 16 µg/mL, showing a bactericidal activity already after one hour of treatment. In summary, the results suggest a possible use of these derivatives for general disinfection practices or antimicrobial agents in cosmesis skin-care.


Assuntos
Anti-Infecciosos/síntese química , Furanos/química , Lignanas/química , Alquilação , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Biofilmes/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Furanos/síntese química , Furanos/farmacologia , Humanos , Lignanas/síntese química , Lignanas/farmacologia , Testes de Sensibilidade Microbiana , Oxirredução , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/fisiologia
6.
J Enzyme Inhib Med Chem ; 35(1): 1751-1764, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32957844

RESUMO

The rapid development of antimicrobial resistance is pushing the search in the discovering of novel antimicrobial molecules to prevent and treat bacterial infections. Self-assembling antimicrobial peptides, as the lipidated peptides, are a novel and promising class of molecules capable of meeting this need. Based on previous work on Temporin L analogs, several new molecules lipidated at the N- or and the C-terminus were synthesised. Our goal is to improve membrane interactions through finely tuning self-assembly to reduce oligomerisation in aqueous solution and enhance self-assembly in bacterial membranes while reducing toxicity against human cells. The results here reported show that the length of the aliphatic moiety is a key factor to control target cell specificity and the oligomeric state of peptides either in aqueous solution or in a membrane-mimicking environment. The results of this study pave the way for the design of novel molecules with enhanced activities.


Assuntos
Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Klebsiella pneumoniae/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Animais , Antibacterianos/síntese química , Antibacterianos/química , Peptídeos Catiônicos Antimicrobianos/síntese química , Peptídeos Catiônicos Antimicrobianos/química , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Humanos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Proteólise/efeitos dos fármacos , Ovinos , Relação Estrutura-Atividade
7.
Molecules ; 25(21)2020 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-33138250

RESUMO

Bacteria are social organisms able to build complex structures, such as biofilms, that are highly organized surface-associated communities of microorganisms, encased within a self- produced extracellular matrix. Biofilm is commonly associated with many health problems since its formation increases resistance to antibiotics and antimicrobial agents, as in the case of Pseudomonas aeruginosa and Staphylococcus aureus, two human pathogens causing major concern. P. aeruginosa is responsible for severe nosocomial infections, the most frequent of which is ventilator-associated pneumonia, while S. aureus causes several problems, like skin infections, septic arthritis, and endocarditis, to name just a few. Literature data suggest that natural products from plants, bacteria, fungi, and marine organisms have proven to be effective as anti-biofilm agents, inhibiting the formation of the polymer matrix, suppressing cell adhesion and attachment, and decreasing the virulence factors' production, thereby blocking the quorum sensing network. Here, we focus on plant derived chemicals, and provide an updated literature review on the anti-biofilm properties of terpenes, flavonoids, alkaloids, and phenolic compounds. Moreover, whenever information is available, we also report the mechanisms of action.


Assuntos
Antibacterianos , Biofilmes/efeitos dos fármacos , Compostos Fitoquímicos , Pseudomonas aeruginosa/fisiologia , Staphylococcus aureus/fisiologia , Antibacterianos/química , Antibacterianos/uso terapêutico , Humanos , Compostos Fitoquímicos/química , Compostos Fitoquímicos/uso terapêutico
8.
New Microbiol ; 42(1): 21-28, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30785206

RESUMO

Antibiotic resistance and biofilm tolerance are among the principal factors involved in the persistence of chronic infections. The need for new antimicrobials is an ever-increasing challenge in clinical environments and in the control of global health. Arylfurans form a set of structures that have been identified in many natural products, e.g. lignans. Lignans are a sub-group of non-flavonoid polyphenols that play an active role in plants' defense against bacteria and fungi infections. The aim of this study was to identify novel synthetic arylfurans and lignan-like arylbenzylfurans exhibiting antimicrobial properties. The molecules synthetized were tested against Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus and S. epidermidis. We found that among tested compounds, arylbenzylfuran 11 was active against S. aureus and S. epidermidis with an MIC of 4 µg ml-1. Compound 11 was also active on methicillin-resistant S. aureus and S. epidermidis. By confocal laser scanning microscopy, we showed that 32 µg ml-1 of compound 11 was able to induce a significant reduction in S. aureus and S. epidermidis biofilms viability. Finally, we demonstrated that compound 11 was not cytotoxic on HaCat cells up to 128 µg ml-1. This work shows the antimicrobial and anti-biofilm potential of a synthetic lignan-like furan.


Assuntos
Anti-Infecciosos , Bactérias , Biofilmes , Lignanas , Viabilidade Microbiana , Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Lignanas/farmacologia , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Microscopia Confocal
9.
Med Mycol ; 56(8): 987-993, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29462476

RESUMO

Cytochrome P450 CYP1A1 and CYP1B1 enzymes are regulated by the aryl hydrocarbon receptor (AhR), a transcription factor activated by a variety of ligands among which Malassezia metabolites. In this study, we analyzed the modulation of CYP1A1, CYP1B1, and AhR in human keratinocytes infected with different strains of Malassezia pachydermatis, as well as the upregulation of some genes involved in the epidermal homeostasis. We demonstrated that all the strains induced AhR activation and its nuclear translocation in HaCaT cells infected for 24 h, compared to untreated cells. The expression of CYP1A1 and CYP1B1, prototypical markers of the AhR signaling pathway, were upregulated with the level of CYP1A1 mRNA approximately 100-fold greater than that for CYP1B1. Filaggrin, involucrin, and TGaseI, proteins involved in epidermal differentiation, were all modulated by Malassezia pachydermatis strains, with the strongest induction observed for filaggrin. By contrast, quinone oxidoreductase 1 (NQO1), which is part of the antioxidant defense system involved in detoxification, was not modulated in our experimental model. In conclusions, our findings suggest that Malassezia pachydermatis infection of human keratinocytes induces activation of the AhR, and increases the expression of its responsive genes and markers of epidermal differentiation, paving the way for occurrence/exacerbation of pathological skin conditions.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/biossíntese , Citocromo P-450 CYP1A1/biossíntese , Queratinócitos/metabolismo , Queratinócitos/microbiologia , Malassezia/crescimento & desenvolvimento , Receptores de Hidrocarboneto Arílico/biossíntese , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Linhagem Celular , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1B1/biossíntese , Citocromo P-450 CYP1B1/genética , Proteínas Filagrinas , Perfilação da Expressão Gênica , Humanos , RNA Mensageiro/análise , RNA Mensageiro/genética , Receptores de Hidrocarboneto Arílico/genética , Transcrição Gênica
10.
Lasers Med Sci ; 33(3): 691, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29368071

RESUMO

In the published online version of the article, the authors' given and family names were incorrectly captured. The corrected names are shown in the author group section above.

11.
Lasers Med Sci ; 33(5): 941-948, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29243020

RESUMO

Candida albicans is an opportunistic pathogen commensal in the oral cavity, vagina, and healthy skin. Common therapeutic options for fungal infections are topical or systemic antifungal drugs. Recently, in cutaneous pathologies, lasers and light-based treatments have emerged showing few contraindications and minimal side effects. The Q-switched (Nd-YAG) laser at a wavelength of 1064 nm has been shown to be useful in dermatology, dentistry, and some other medical specialties. It is used to treat onychomycoses, warts, and wounds and in some other treatments. We analyzed the effect of Q-switched (Nd-YAG) laser 1064 nm on human keratinocytes infected with C. albicans. In particular, we evaluated the effect of laser on invasiveness of C. albicans and on inflammatory and protective response of HaCaT cells infected. The results obtained did not show inhibitory, fungicidal, or fungistatic effects of laser on yeast; in addition, laser did not affect HaCaT vitality. HaCaT cells infected with C. albicans and irradiated with laser showed a reduction of invasiveness of TNF-α and IL8 gene expression and an increase of immunomodulatory cytokines such as TGFß. Furthermore, laser induces a significant over-expression of HSP70B (heat shock protein) and of HBD-2 (Human ß defensin-2) in HaCaT infected with C. albicans, compared to the untreated control. The use of Q-switched Nd:YAG laser in skin mycosis caused by C. albicans reduces yeast invasiveness in keratinocytes, downregulates inflammatory activities, and facilitates cytoprotection and antimicrobial defense. Our results offer a promising therapeutic strategy in the management of skin candidiasis, also in combination with conventional therapies.


Assuntos
Candida albicans/efeitos da radiação , Imunidade Inata/efeitos da radiação , Queratinócitos/imunologia , Queratinócitos/microbiologia , Lasers de Estado Sólido/uso terapêutico , Linhagem Celular , Sobrevivência Celular/efeitos da radiação , Feminino , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Humanos , Inflamação/patologia , Queratinócitos/patologia , Queratinócitos/efeitos da radiação , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Regulação para Cima/efeitos da radiação , beta-Defensinas/genética , beta-Defensinas/metabolismo
12.
Microbiology (Reading) ; 163(5): 654-663, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28535856

RESUMO

Chlamydia trachomatis is the most prevalent infection of the genital tract in women worldwide. C. trachomatis has a tendency to cause persistent infection and induce a state of chronic inflammation, which has been reported to play a role in carcinogenesis. We report that persistent C. trachomatis infection increases the expression of inflammatory tumour cytokines and upregulates molecular biomarkers such as podoplanin, Wilms' tumour gene 1 and osteopontin in primary cultures of mesothelial cells (Mes1) and human mesothelioma cells (NCI). Infection experiments showed that Mes1 and NCI supported the growth of C. trachomatisin vitro, and at an m.o.i. of 4, the inclusion-forming units/cell showed many intracellular inclusion bodies after 3 days of infection. However, after 7 days of incubation, increased proliferative and invasive activity was also observed in Mes1 cells, which was more evident after 14 days of incubation. ELISA analysis revealed an increase in vascular endothelial growth factor, IL-6, IL-8, and TNF-α release in Mes1 cells infected for a longer period (14 days). Finally, real-time PCR analysis revealed a strong induction of podoplanin, Wilms' tumour gene 1 and osteopontin gene expression in infected Mes1 cells. The aim of the present study was to investigate the inflammatory response elicited by C. trachomatis persistent infection and the role played by inflammation in cell proliferation, secretion of proinflammatory cytokines and molecular biomarkers of cancer. The results of this study suggest that increased molecular biomarkers of cancer by persistent inflammation from C. trachomatis infection might support cellular transformation, thus increasing the risk of cancer.


Assuntos
Chlamydia trachomatis/imunologia , Citocinas/biossíntese , Células Epiteliais/metabolismo , Glicoproteínas de Membrana/biossíntese , Mesotelioma/patologia , Proteínas Nucleares/biossíntese , Osteopontina/biossíntese , Proteínas de Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Infecções por Chlamydia/microbiologia , Infecções por Chlamydia/patologia , Epitélio/metabolismo , Células HeLa , Humanos , Inflamação/imunologia , Invasividade Neoplásica/patologia , Fatores de Processamento de RNA
13.
Microb Pathog ; 108: 71-77, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28479510

RESUMO

Naturally derived compounds represent a potential source of pharmacologically active drugs able to contrast different diseases, including gastric cancer, a multifactorial disease, in which the important role played by H. pylori infection has been demonstrated. Carexanes, stilbene derivatives, isolated from plants of the Carex distachya Desf., are unusual secondary metabolites with a tetracyclic skeleton arising from a cyclization of prenylstilbenoid precursors. In this study we firstly showed the ability of three purified carexanes CxB, CxG, and CxI to enhance the antioxidant response of AGS cells and to contrast the effect of the H. pylori's protein HspB. Among them CxI was the molecule that best modified the expression of genes involved in the antioxidant response. In particular, CxI was able to reduce Keap-1 gene expression and induce NQO1 gene expression, both at 4 and 24 h in AGS cells, as showed by real time PCR. Nrf2 induction was evident only at 24 h. Interestingly, the effect of CxI was stronger in HspB-transfected AGS cells, where Keap-1 gene expression was nearly abrogated. Finally, we demonstrated that CxI was able to reduce also COX-2 gene expression in HspB-transfected AGS cells, compared with untreated HspB-transfected cells, both at 4 and 24 h. This study first report that carexanes might represent candidate molecules able to contrast the deleterious effect of HspB protein but also to reduce the inflammatory process induced by H. pylori infection.


Assuntos
Antioxidantes/metabolismo , Proteínas de Bactérias/metabolismo , Proteínas de Choque Térmico/metabolismo , Infecções por Helicobacter/genética , Helicobacter pylori/patogenicidade , Estilbenos/farmacologia , Carex (Planta)/química , Técnicas de Cultura de Células , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Ciclo-Oxigenase 2/efeitos dos fármacos , Ciclo-Oxigenase 2/genética , Células Epiteliais , Mucosa Gástrica/efeitos dos fármacos , Expressão Gênica , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch/efeitos dos fármacos , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Fator 2 Relacionado a NF-E2/metabolismo , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Estilbenos/química , Neoplasias Gástricas/tratamento farmacológico , Transfecção
14.
Int J Mol Sci ; 18(2)2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-28212280

RESUMO

Urinary tract infections (UTIs) and catheter-associated UTIs (CAUTIs) are the principal hospital-acquired infections. Proteus mirabilis is characterized by several virulence factors able to promote adhesion and biofilm formation and ameliorate the colonization of urinary tract and the formation of crystalline biofilms on the abiotic surface of the urinary catheters. Since, to date, the role of P. mirabilis in the etiopathogenesis of different types of urinary tract infections is not well established, in this study we sought to characterize two different clinically isolated strains of P. mirabilis (PM1 and PM2) with distinctive phenotypes and analyzed various virulence factors possibly implicated in the ability to induce UTIs and CAUTIs. In particular, we analyzed motility, biofilm formation both on abiotic and biotic surfaces of PM1 and PM2 and paralleled these parameters with the ability to induce an inflammatory response in an epithelial cell model. Results showed that PM1 displayed major motility and a capacity to form biofilm and was associated with an anti-inflammatory response of host cells. Conversely, PM2 exhibited lack motility and a had slower organization in biofilm but promoted an increase of proinflammatory cytokine expression in infected epithelial cells. Our study provides data useful to start uncovering the pathologic basis of P. mirabilis-associated urinary infections. The evidence of different virulence factors expressed by PM1 and PM2 highlights the possibility to use precise and personalized therapies targeting specific virulence pathways.


Assuntos
Biofilmes/crescimento & desenvolvimento , Imunomodulação , Infecções por Proteus/imunologia , Infecções por Proteus/microbiologia , Proteus mirabilis/fisiologia , Regulação Bacteriana da Expressão Gênica , Genes Bacterianos , Interações Hospedeiro-Patógeno/imunologia , Humanos , Fenótipo , Proteus mirabilis/classificação , Proteus mirabilis/isolamento & purificação , Infecções Urinárias/imunologia , Infecções Urinárias/microbiologia , Fatores de Virulência
15.
Adv Exp Med Biol ; 901: 59-76, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26864271

RESUMO

Defensins are a group of antimicrobial peptides (AMPs) found in different living organisms, and are involved in the first line of defense in the innate immune response against pathogens. The increase in the resistance of bacteria to conventional antibiotics and the need for new antibiotics has stimulated interest in the use of AMPs as new therapeutic agents. The inducible nature of human defensin genes suggests that it is possible to increase the endogenous production by utilizing small molecules of various origins to enhance, even selectively, the expression of these peptides. In the light of their role in immunomodulation, angiogenesis, wound healing, inflammation and cancer, as well as their antimicrobial activity, it is possible induce their expression or create analogs with increased specific activity or various degrees of selectivity, or obtain human defensins with genetic engineering to optimize the potency and safety in order to reduce cytotoxicity and potential proinflammatory activity and susceptibility to protease and salt. Restoring the balance between immunostimulating and immunosuppressive molecules may be an important strategy to correct expression defects in specific diseases.


Assuntos
Fatores Imunológicos/farmacologia , Imunossupressores/farmacologia , beta-Defensinas/farmacologia , Animais , Tratamento Farmacológico , Humanos , Imunidade Inata , Fatores Imunológicos/química , Fatores Imunológicos/genética , Fatores Imunológicos/imunologia , Imunomodulação , Imunossupressores/química , Imunossupressores/imunologia , beta-Defensinas/química , beta-Defensinas/genética , beta-Defensinas/imunologia
16.
New Microbiol ; 39(3): 216-223, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27284984

RESUMO

Malassezia pachydermatis is a yeast belonging to the microbiota of the skin and mucous membranes of dog and cat, but it can also act as pathogen, causing dermatitis. The aim of this work was to evaluate the genetic variability of M. pachydermatis strains isolated from symptomatic dogs and cats and determine a correlation between genotype and phenotype. For this purpose eleven strains of M. pachydermatis were molecularly classified by nested-polymerase chain reaction (nested-PCR) based on ITS-1 and ITS-2 regions, specific for fungal rRNA genes. Furthermore, random amplification of polymorphic DNA (RAPD) was applied for genetic typing of M. pachydermatis isolates identifying four different genotypes. Strains belonging to genotype 1 produced the highest amount of biofilm and phospholipase activity. The inflammatory response induced by M. pachydermatis strains in immortalized human keratinocytes (HaCat cells) was significantly different when we compared the results obtained from each strain. In particular, HaCat cells infected with the strains belonging to genotypes 1 and 2 triggered the highest levels of increase in TLR-2, IL-1ß, IL-6, IL-8, COX-2 and MMP-9 expression. By contrast, cells infected with the strains of genotype 3 and those of genotype 4 did not significantly induce TLR-2 and cytokines. The results obtained might suggest a possible association between genotype and virulence factors expressed by M. pachydermatis strains. This highlights the need for a more accurate identification of the yeast to improve the therapeutic approach and to monitor the onset of human infections caused by this emergent zoonotic pathogen.


Assuntos
Doenças do Gato/microbiologia , Dermatomicoses/veterinária , Doenças do Cão/microbiologia , Malassezia/genética , Malassezia/metabolismo , Fatores de Virulência/metabolismo , Animais , Gatos , DNA Fúngico/genética , Dermatomicoses/microbiologia , Cães , Regulação Fúngica da Expressão Gênica , Variação Genética , Genótipo , Fatores de Virulência/genética
17.
Int J Med Microbiol ; 305(8): 815-27, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26372530

RESUMO

Chlamydia trachomatis, a human pathogen, is a Gram-negative bacillus and a compulsory intracellular parasite. It is the most common cause of bacterial sexually transmitted infections in both industrialized and developing countries. In women, untreated genital infections can result in devastating consequences such as pelvic inflammatory disease, ectopic pregnancy, and even infertility. Lactobacillus crispatus is an important urogenital species that is routinely found in the vagina of healthy women. Lactobacilli are involved in the maintenance of the normal vaginal microbiota and their dominance in the vagina suggests that they play a crucial role in protecting the genitourinary tract against pathological conditions. Lactobacilli can act through the activation of the immune system, but C. trachomatis is able to effectively evade immune surveillance in some individuals. The aim of our study was to investigate the immunomodulatory efficacy of the potential probiotic strain L. crispatus in HeLa and J774 cells subjected to C. trachomatis infection by studying the expression of the inflammatory cytokines IL-6, IL-8, TNF-α and IL-10. Our results demonstrated, firstly, the lack of any cytotoxic effect on the epithelial cells and macrophages when treated with L. crispatus and its supernatant; in addition, L. crispatus and its supernatant inhibited C. trachomatis adhesion and infectivity in human epithelial cells and macrophages. Our study then showed that L. crispatus and its supernatant reduced IL-6, IL-8 and TNF-α production in C. trachomatis-infected HeLa and J774 cells. In contrast, a significant upregulation of the IL-10 expression in HeLa and J774 cells by L. crispatus and supernatant was also demonstrated. Our data indicate that L. crispatus specifically enhances the production of the IL-10 anti-inflammatory cytokine in contrast to the inhibitory effect of L. crispatus on the pro-inflammatory cytokines.


Assuntos
Anti-Inflamatórios/metabolismo , Chlamydia trachomatis/imunologia , Interleucina-10/metabolismo , Lactobacillus/imunologia , Interações Microbianas , Animais , Aderência Bacteriana , Linhagem Celular , Chlamydia trachomatis/fisiologia , Células Epiteliais/imunologia , Células Epiteliais/microbiologia , Feminino , Humanos , Lactobacillus/fisiologia , Macrófagos/imunologia , Macrófagos/microbiologia , Camundongos
18.
Front Microbiol ; 15: 1340585, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38371939

RESUMO

Bacterial infections represent a key public health issue due to the occurrence of multidrug-resistant bacteria. Recently, the amount of data supporting the dynamic control of epigenetic pathways by environmental cues has triggered research efforts toward the clarification of their role in microbial infections. Among protein post-translational modifications, reversible acetylation is the most implicated in the feedback to environmental stimuli and in cellular homeostasis. Accordingly, the latest studies identified the histone deacetylase 6 (HDAC6) enzyme as a crucial player in the complex molecular machinery underlying bacterial clearance or killing. A very important milestone for the elucidation of the consequence of HDAC6 activity in bacterial infections is herein described, unveiling for the first time the role of a potent HDAC6 inhibitor in interfering with biofilm formation and modulating virulence factors of P. aeruginosa. We demonstrated that compound F2F-2020202 affected the production of some important virulence factors in P. aeruginosa, namely pyocyanin and rhamnolipids, clearly impairing its ability to form biofilm. Furthermore, evidence of possible QS involvement is supported by differential regulation of specific genes, namely RhlI, phAz1, and qsrO. The data herein obtained also complement and in part explain our previous results with selective HDAC6 inhibitors able to reduce inflammation and bacterial load in chronic infection models recapitulating the cystic fibrosis (CF) phenotype. This study fosters future in-depth investigation to allow the complete elucidation of the molecular mechanisms underlying HDAC6's role in bacterial infections.

19.
Eur J Med Chem ; 264: 115981, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38086192

RESUMO

The occurrence of increased antibiotic resistance has reduced the availability of drugs effective in the control of infectious diseases, especially those caused by various combinations of bacteria and/or fungi that are often associated with poorer patient outcomes. In the hunt for novel antibiotics of interest to treat polymicrobial diseases, molecules bearing guanidine moieties have recently come to the fore in designing and optimizing antimicrobial agents. Due to their remarkable antibacterial and antifungal activities, labdane diterpenes are also attracting increasing interest in antimicrobial drug discovery. In this study, six different guanidines prenylated with labdanic fragments were synthesized and evaluated for their antimicrobial properties. Assays were carried out against both non-resistant and antibiotic-resistant bacteria strains, while their possible antifungal activities have been tested on the yeast Candida albicans. Two of the synthesized compounds, namely labdan-8,13(R)-epoxy-15-oyl guanidine and labdan-8,13(S)-epoxy-15-oyl guanidine, were finally selected as the best candidates for further developments in drug discovery, due to their antimicrobial effects on both Gram-negative and Gram-positive bacterial strains, their fungicide action, and their moderate toxicity in vivo on zebrafish embryos. The study also provides insights into the structure-activity relationships of the guanidine-functionalized labdane-type diterpenoids.


Assuntos
Anti-Infecciosos , Diterpenos , Animais , Humanos , Antifúngicos/farmacologia , Guanidina/farmacologia , Peixe-Zebra , Anti-Infecciosos/farmacologia , Antibacterianos/farmacologia , Bactérias , Diterpenos/farmacologia , Candida albicans , Guanidinas/farmacologia , Testes de Sensibilidade Microbiana
20.
Bioorg Med Chem ; 21(22): 7038-46, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24094434

RESUMO

Two new acylated styrylpyrones, one 5-methoxy-1(3H)-isobenzofuranone glucoside and a hydroxymethyl-orcinol derivative, along with sixteen known aromatic metabolites, including lignans, quinic acid derivatives low-molecular weight phenol glucosides, have been isolated from the methanol extract of Helichrysum italicum, a medicinal plant typical of the Mediterranean vegetation. The structures of these compounds have been elucidated on the basis of extensive 2D-NMR spectroscopic analyses, including COSY, TOCSY, HSQC, CIGAR-HMBC, H2BC and HSQC-TOCSY, along with Q-TOF HRMS(2) analysis. Selected compounds were evaluated for their anti-biofilm properties against Pseudomonas aeruginosa.


Assuntos
Biofilmes/efeitos dos fármacos , Helichrysum/química , Extratos Vegetais/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Antibacterianos/química , Antibacterianos/farmacologia , Glucosídeos/química , Glucosídeos/isolamento & purificação , Glucosídeos/farmacologia , Espectroscopia de Ressonância Magnética , Conformação Molecular , Extratos Vegetais/química , Folhas de Planta/química , Plantas Medicinais/química , Resorcinóis/química , Resorcinóis/isolamento & purificação , Resorcinóis/farmacologia
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