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1.
Microb Pathog ; 194: 106835, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39117014

RESUMO

Candida albicans is an opportunistic yeast accounting for about 50-90 % of all cases of candidiasis in humans, ranging from superficial to systemic potentially life-threatening infections. The presence of several virulence factors, including biofilm, hyphal transition, and proteolytic enzymes production, worsens the fungal infections burden on healthcare system resources. Hence, developing new bioactive compounds with antifungal activity is a pressing urgence for the scientific community. In this perspective, we evaluated the anti-Candida potential of the N-Nitroso-N-phenylhydroxylamine ammonium salt (cupferron) against standard and clinical C. albicans strains. Firstly, the in vitro cytotoxicity of cupferron was checked in the range 400-12.5 µg/mL against human microglial cells (HMC-3). Secondly, its antifungal spectrum was explored via disk diffusion test, broth-microdilution method, and time-killing curve analysis, validating the obtained results through scanning electron microscopy (SEM) observations. Additionally, we evaluated the cupferron impact on the main virulence determinants of Candida albicans. At non-toxic concentrations (100-12.5 µg/mL), the compound exerted interesting anti-Candida activity, registering a minimum inhibitory concentration (MIC) between 50 and 100 µg/mL against the tested strains, with a fungistatic effect until 100 µg/mL. Furthermore, cupferron was able to counteract fungal virulence at MIC and sub-MIC values (50-12.5 µg/mL). These findings may propose cupferron as a new potential antifungal option for the treatment of Candida albicans infections.

2.
J Pept Sci ; 30(7): e3593, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38471710

RESUMO

In recent decades, the global rise of viral emerging infectious diseases has posed a substantial threat to both human and animal health worldwide. The rapid spread and accumulation of mutations into viruses, and the limited availability of antiviral drugs and vaccines, stress the urgent need for alternative therapeutic strategies. Antimicrobial peptides (AMPs) derived from natural sources present a promising avenue due to their specificity and effectiveness against a broad spectrum of pathogens. The present study focuses on investigating the antiviral potential of oreochromicin-1 (oreoch-1), a fish-derived AMP obtained from Nile tilapia, against a wide panel of animal viruses including canine distemper virus (CDV), Schmallenberg virus (SBV), caprine herpesvirus 1 (CpHV-1), and bovine herpesvirus 1 (BoHV-1). Oreoch-1 exhibited a strong antiviral effect, demonstrating an inhibition of infection at concentrations in the micromolar range. The mechanism of action involves the interference with viral entry into host cells and a direct interaction between oreoch-1 and the viral envelope. In addition, we observed that the peptide could also interact with the cell during the CDV infection. These findings not only highlight the efficacy of oreoch-1 in inhibiting viral infection but also emphasize the potential of fish-derived peptides, specifically oreoch-1, as effective antiviral agents against viral infections affecting animals, whose potential to spill into humans is high. This research contributes valuable insights to the ongoing quest for novel antiviral drugs with the potential to mitigate the impact of infectious diseases on a global scale.


Assuntos
Antivirais , Animais , Antivirais/farmacologia , Antivirais/química , Peptídeos Antimicrobianos/farmacologia , Peptídeos Antimicrobianos/química , Humanos , Testes de Sensibilidade Microbiana , Chlorocebus aethiops , Internalização do Vírus/efeitos dos fármacos
3.
J Appl Microbiol ; 135(7)2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38991986

RESUMO

AIM: The high incidence of virus-related infections and the large diffusion of drug-resistant pathogens stimulate the search and identification of new antiviral agents with a broad spectrum of action. Antivirals can be designed to act on a single target by interfering with a specific step in the viral lifecycle. On the contrary, antiviral peptides (AVPs) are known for acting on a wide range of viruses, with a diversified mechanism of action targeting virus and/or host cell. In the present study, we evaluated the antiviral potential of the peptide Hylin-a1 secreted by the frog Hypsiobas albopunctatus against members of the Herpesviridae family. METHODS AND RESULTS: The inhibitory capacity of the peptide was evaluated in vitro by plaque assays in order to understand the possible mechanism of action. The results were also confirmed by real-time PCR and Western blot evaluating the expression of viral genes. Hylin-a1 acts to block the herpetic infection interfering at the early stages of both herpes simplex virus type 1 (HSV-1) and type 2 infection. Its mechanism is mainly directed on the membrane, probably by damaging the viral envelope. The same effect was also observed against HSV-1 strains resistant to acyclovir. CONCLUSIONS: The data presented in this study, such as the increased activity of the peptide when combined to acyclovir, a weak hemolytic profile, an anti-inflammatory effect, and a tolerable half-life in serum, indicates Hylin-a1 as a novel antiherpetic molecule with promising potential in the clinical setting.


Assuntos
Anti-Inflamatórios , Antivirais , Anuros , Animais , Antivirais/farmacologia , Anti-Inflamatórios/farmacologia , Herpesvirus Humano 1/efeitos dos fármacos , Proteínas de Anfíbios/farmacologia , Peptídeos/farmacologia , Células Vero , Chlorocebus aethiops
4.
New Microbiol ; 47(2): 164-171, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39023526

RESUMO

The study objective is to examine epidemiological and microbiological aspects of aerobic vaginitis in female patients admitted to University Hospital of Campania "L. Vanvitelli" over five years. The most represented strains were E. coli (n = 153), Citrobacter spp. increasing from 2020, E. faecalis (n = 149), S. haemolitycus (n = 61), and Candida albicans (n = 87). The susceptibility patterns of a selection of gram-negative and gram-positive representative bacterial isolates were examined. Carbapenems, aminoglycosides, and fosfomycin were most effective against gram-negative bacteria, whereas vancomycin, daptomycin, and linezolid exhibited greater efficacy against gram-positive bacteria. None of the E. coli and Citrobacter spp. isolates produced extended-spectrum beta-lactamases, and the S. haemolyticus strains were methicillin-resistant. In gram-positive isolates, gentamicin susceptibility increased in 2020 and 2021 compared to clindamycin; erythromycin showed high resistance rates in 2020. Our findings indicate that integrating proper microbiological cultures into clinical practice could improve the management of aerobic vaginitis. Moreover, they highlight the necessity of establishing a nationwide surveillance guideline to mitigate antimicrobial resistance. Improvement actions in antimicrobial diagnostic stewardship must be considered when seeking the appropriate diagnosis and treatment for aerobic vaginitis.


Assuntos
Antibacterianos , Gestão de Antimicrobianos , Testes de Sensibilidade Microbiana , Feminino , Humanos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Adulto , Farmacorresistência Bacteriana , Pessoa de Meia-Idade , Vaginose Bacteriana/microbiologia , Vaginose Bacteriana/tratamento farmacológico , Vaginose Bacteriana/diagnóstico , Adulto Jovem , Vaginite/microbiologia , Vaginite/tratamento farmacológico
5.
J Appl Microbiol ; 134(10)2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37796875

RESUMO

AIMS: Multidrug resistance is a worrying problem worldwide. The lack of readily available drugs to counter nosocomial infections requires the need for new interventional strategies. Drug repurposing represents a valid alternative to using commercial molecules as antimicrobial agents in a short time and with low costs. Contextually, the present study focused on the antibacterial potential of the ammonium salt N-nitroso-N-phenylhydroxylamine (Cupferron), evaluating the ability to inhibit microbial growth and influence the main virulence factors. METHODS AND RESULTS: Cupferron cytotoxicity was checked via 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and hemolysis assays. The antimicrobial activity was assessed through the Kirby-Bauer disk diffusion test, broth microdilution method, and time-killing kinetics. Furthermore, the impact on different stages of the biofilm life cycle, catalase, swimming, and swarming motility was estimated via MTT and crystal violet (CV) assay, H2O2 sensitivity, and motility tests, respectively. Cupferron exhibited <15% cytotoxicity at 200 µg/mL concentration. The 90% bacterial growth inhibitory concentrations (MIC90) values recorded after 24 hours of exposure were 200 and 100 µg/mL for multidrug-resistant (MDR) and sensitive strains, respectively, exerting a bacteriostatic action. Cupferron-treated bacteria showed increased susceptibility to biofilm production, oxidative stress, and impaired bacterial motility in a dose-dependent manner. CONCLUSIONS: In the new antimicrobial compounds active research scenario, the results indicated that Cupferron could be an interesting candidate for tackling Escherichia coli infections.


Assuntos
Infecções por Escherichia coli , Escherichia coli , Humanos , Virulência , Peróxido de Hidrogênio , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/microbiologia , Biofilmes
6.
Mar Drugs ; 21(7)2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37504915

RESUMO

In the last decades, the interest in bioactive compounds derived from natural sources including bacteria, fungi, plants, and algae has significantly increased. It is well-known that aquatic or terrestrial organisms can produce, in special conditions, secondary metabolites with a wide range of biological properties, such as anticancer, antioxidant, anti-inflammatory, and antimicrobial activities. In this study, we focused on the extremophilic microalga Galdieria sulphuraria as a possible producer of bioactive compounds with antiviral activity. The algal culture was subjected to organic extraction with acetone. The cytotoxicity effect of the extract was evaluated by the 2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. The antiviral activity was assessed through a plaque assay against herpesviruses and coronaviruses as enveloped viruses and poliovirus as a naked one. The monolayer was treated with different concentrations of extract, ranging from 1 µg/mL to 200 µg/mL, and infected with viruses. The algal extract displayed strong antiviral activity at non-toxic concentrations against all tested enveloped viruses, in particular in the virus pre-treatment against HSV-2 and HCoV-229E, with IC50 values of 1.7 µg/mL and IC90 of 1.8 µg/mL, respectively. However, no activity against the non-enveloped poliovirus has been detected. The inhibitory effect of the algal extract was confirmed by the quantitative RT-PCR of viral genes. Preliminary chemical profiling of the extract was performed using ultra-high-performance liquid chromatography coupled to high-resolution mass spectrometry (UHPLC-HRMS), revealing the enrichment in primary fatty acid amides (PFAA), such as oleamide, palmitamide, and pheophorbide A. These promising results pave the way for the further purification of the mixture to explore its potential role as an antiviral agent.


Assuntos
Infecções por Coronavirus , Rodófitas , Vírus , Humanos , Antivirais/química , Rodófitas/metabolismo , Extratos Vegetais/farmacologia
7.
Int J Mol Sci ; 24(18)2023 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-37762191

RESUMO

Pandemic and epidemic outbreaks of respiratory viruses are a challenge for public health and social care system worldwide, leading to high mortality and morbidity among the human populations. In light of the limited efficacy of current vaccines and antiviral drugs against respiratory viral infections and the emergence and re-emergence of new viruses, novel broad-spectrum antiviral drugs are needed for the prevention and treatment of these infections. Antimicrobial peptides with an antiviral effect, also known as AVPs, have already been reported as potent inhibitors of viral infections by affecting different stages of the virus lifecycle. In the present study, we analyzed the activity of the AVP Hylin-a1, secreted by the frog Hypsiboas albopunctatus, against a wide range of respiratory viruses, including the coronaviruses HCoV-229E and SARS-CoV-2, measles virus, human parainfluenza virus type 3, and influenza virus H1N1. We report a significant inhibitory effect on infectivity in all the enveloped viruses, whereas there was a lack of activity against the naked coxsackievirus B3. Considering the enormous therapeutic potential of Hylin-a1, further experiments are required to elucidate its mechanism of action and to increase its stability by modifying the native sequence.


Assuntos
COVID-19 , Coronavirus Humano 229E , Vírus da Influenza A Subtipo H1N1 , Humanos , Animais , SARS-CoV-2 , Antivirais/farmacologia , Antivirais/uso terapêutico , Anuros
8.
New Microbiol ; 45(4): 338-343, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36538299

RESUMO

The aim of this study was to describe the prevalence and epidemiology distribution of K. pneumoniae isolated at University Hospital of Campania "Luigi Vanvitelli," including the susceptibility evolution profile. Data on resistant phenotype strains, such as extended-spectrum-ß-lactamase (ESBL) producers and carbapenem-resistant K. pneumoniae (CRE) isolates, were also reported. K. pneumoniae strains were collected at the Complex Operative Unit (UOC) of Virology and Microbiology from different colonization and infection sites from January 2016 to December 2020. The highest rates of isolation were in urinary samples and in respiratory and wound swabs. Antibiotics susceptibility patterns showed more than 50% of the isolates resistant to cephalosporins, fluoroquinolones and penicillin. On the other hand, from 20% to 40% of K. pneumoniae strains were resistant to carbapenems and aminoglycosides. Based on our analysis, fosfomycin, ceftazidime/avibactam and ceftolozane/tazobactam are still therapeutic alternatives. Data analysis on carbapenem class evolution in 2016-2020 showed a significant increase in resistance rates (p<0.05). Increased rates in CRE and ESBL producing K. pneumoniae since 2017 were reported. Providing information on clinical characteristics and epidemiology data on contemporary K. pneumoniae evolution could help mitigate the spread of these isolates in our hospital and avert the endemic levels that have been observed in Southern Italy and in other European countries.


Assuntos
Fosfomicina , Infecções por Klebsiella , Humanos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Klebsiella pneumoniae/genética , Farmacorresistência Bacteriana , Carbapenêmicos/farmacologia , Testes de Sensibilidade Microbiana , beta-Lactamases/genética , Infecções por Klebsiella/epidemiologia , Infecções por Klebsiella/tratamento farmacológico
9.
New Microbiol ; 45(4)2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-36066216

RESUMO

Viral hepatitis still represents a significant worldwide public health issue, being an important cause of morbidity and mortality. The aim of our study is to evaluate the prevalence of Hepatitis B virus (HBV) markers from serologic analysis of hospitalized patients at University Hospital of Campania "Luigi Vanvitelli" and also to investigate the prevalence of HBV/HCV coinfection. We screened serum Anti-Hepatitis B surface antigen (HBsAg), antibody to HBsAg (anti-HBs), antibody to hepatitis B core antigen (anti-HBc), and antibody to Hepatitis C Virus (Anti-HCV) Anti-HCV from January to December 2020. Analyses of HBV serological profile based on age showed that the 51-60 age group was the most numerous and with the highest cases of HBsAg. The 61-70 age group recorded the highest prevalence of anti-HBc while age groups 0-10 years and 31-40 years the highest cases of anti-HBs. Antibody levels decline with time. In subjects older than 20 years, compared to vaccinated cohort individuals, anti-HBc seropositive prevalence increased linearly. This study underlined, in our geographic region, the decreased incidence of hepatitis B and high immunogenicity in the young population. Therefore, administration of HBV vaccine booster dose should be considered for the population rather than vaccination in the first year of life. In conclusion, our findings reaffirm the importance of health surveillance in hospitalized subjects, stressing the need to improve immunized subjects to increase the general population's health.

10.
Int J Mol Sci ; 23(2)2022 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-35055066

RESUMO

Viral infections represent a serious threat to the world population and are becoming more frequent. The search and identification of broad-spectrum antiviral molecules is necessary to ensure new therapeutic options, since there is a limited availability of effective antiviral drugs able to eradicate viral infections, and consequently due to the increase of strains that are resistant to the most used drugs. Recently, several studies on antimicrobial peptides identified them as promising antiviral agents. In detail, amphibian skin secretions serve as a rich source of natural antimicrobial peptides. Their antibacterial and antifungal activities have been widely reported, but their exploitation as potential antiviral agents have yet to be fully investigated. In the present study, the antiviral activity of the peptide derived from the secretion of Rana tagoi, named AR-23, was evaluated against both DNA and RNA viruses, with or without envelope. Different assays were performed to identify in which step of the infectious cycle the peptide could act. AR-23 exhibited a greater inhibitory activity in the early stages of infection against both DNA (HSV-1) and RNA (MeV, HPIV-2, HCoV-229E, and SARS-CoV-2) enveloped viruses and, on the contrary, it was inactive against naked viruses (PV-1). Altogether, the results indicated AR-23 as a peptide with potential therapeutic effects against a wide variety of human viruses.


Assuntos
Proteínas de Anfíbios/farmacologia , Peptídeos Antimicrobianos/farmacologia , Antivirais/farmacologia , Ranidae/metabolismo , Animais , Peptídeos Catiônicos Antimicrobianos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Vírus de DNA/efeitos dos fármacos , Vírus de RNA/efeitos dos fármacos , SARS-CoV-2/efeitos dos fármacos , Células Vero , Envelope Viral/efeitos dos fármacos , Ensaio de Placa Viral , Viroses/tratamento farmacológico
11.
Int J Mol Sci ; 23(4)2022 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-35216177

RESUMO

The COVID-19 pandemic has evidenced the urgent need for the discovery of broad-spectrum antiviral therapies that could be deployed in the case of future emergence of novel viral threats, as well as to back up current therapeutic options in the case of drug resistance development. Most current antivirals are directed to inhibit specific viruses since these therapeutic molecules are designed to act on a specific viral target with the objective of interfering with a precise step in the replication cycle. Therefore, antimicrobial peptides (AMPs) have been identified as promising antiviral agents that could help to overcome this limitation and provide compounds able to act on more than a single viral family. We evaluated the antiviral activity of an amphibian peptide known for its strong antimicrobial activity against both Gram-positive and Gram-negative bacteria, namely Temporin L (TL). Previous studies have revealed that TL is endowed with widespread antimicrobial activity and possesses marked haemolytic activity. Therefore, we analyzed TL and a previously identified TL derivative (Pro3, DLeu9 TL, where glutamine at position 3 is replaced with proline, and the D-Leucine enantiomer is present at position 9) as well as its analogs, for their activity against a wide panel of viruses comprising enveloped, naked, DNA and RNA viruses. We report significant inhibition activity against herpesviruses, paramyxoviruses, influenza virus and coronaviruses, including SARS-CoV-2. Moreover, we further modified our best candidate by lipidation and demonstrated a highly reduced cytotoxicity with improved antiviral effect. Our results show a potent and selective antiviral activity of TL peptides, indicating that the novel lipidated temporin-based antiviral agents could prove to be useful additions to current drugs in combatting rising drug resistance and epidemic/pandemic emergencies.


Assuntos
Proteínas de Anfíbios/farmacologia , Anfíbios/metabolismo , Peptídeos Catiônicos Antimicrobianos/farmacologia , Antivirais/química , Vírus de DNA/efeitos dos fármacos , Vírus de RNA/efeitos dos fármacos , Sequência de Aminoácidos , Proteínas de Anfíbios/química , Proteínas de Anfíbios/metabolismo , Animais , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/metabolismo , Antivirais/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Lipídeos/química , SARS-CoV-2/efeitos dos fármacos , Células Vero
12.
Molecules ; 27(13)2022 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-35807518

RESUMO

In the present study, a hydroxytyrosol-rich Olea europaea L. fruit extract (OFE) was added to three thoroughly green formulations-hydrogel, oleogel, and cream-in order to evaluate their antiviral activity against HSV-1. The extract was characterized by different analytical techniques, i.e., FT-IR, XPS, and TGA. HPLC analyses were carried out to monitor the content and release of hydroxytyrosol in the prepared formulations. The total polyphenol content and antioxidant activity were investigated through Folin-Ciocâlteu's reagent, DPPH, and ABTS assays. The ability of the three formulations to convey active principles to the skin was evaluated using a Franz cell, showing that the number of permeated polyphenols in the hydrogel (272.1 ± 1.8 GAE/g) was significantly higher than those in the oleogel and cream (174 ± 10 and 179.6 ± 2 GAE/g, respectively), even if a negligible amount of hydroxytyrosol crossed the membrane for all the formulations. The cell viability assay indicated that the OFE and the three formulations were not toxic to cultured Vero cells. The antiviral activity tests highlighted that the OFE had a strong inhibitory effect against HSV-1 with a 50% inhibitory concentration (IC50) at 25 µg/mL, interfering directly with the viral particles. Among the three formulations, the hydrogel exhibited the highest antiviral activity also against the acyclovir-resistant strain.


Assuntos
Herpesvirus Humano 1 , Olea , Animais , Antioxidantes/análise , Antioxidantes/farmacologia , Antivirais/análise , Antivirais/farmacologia , Chlorocebus aethiops , Frutas/química , Hidrogéis/farmacologia , Olea/química , Extratos Vegetais/química , Polifenóis/análise , Polifenóis/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Células Vero
13.
Lasers Med Sci ; 36(5): 1047-1057, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32979135

RESUMO

During the last years, several attempts have been accomplished to improve the wound healing. Device application aimed at enhancing skin ability to reconstruct its damaged sites through a proper dermal regenerative process. In particular, Q-switched Nd-YAG laser (Medlite C6 laser, Conbio, USA) applied with a fluence of 8 J/cm2, a pulse width of 5 ns, and a spot size of 4 mm exerts a photo-mechanical action that improve skin repair. Besides, hyaluronan hybrid cooperative complexes (HCC) widely exploited in dermoesthetic applications proved specific actions on keratinocytes and fibroblasts monolayer repair. We evaluated this specific laser treatment in vitro on a wound healing model based on human keratinocytes (HaCaT) alone and in combination with HCC. In addition, we evaluated key biomarkers of dermal repair. Scratched HaCaT monolayers were treated with laser and successively with HA-based formulations (HHA and HCC). For each treatment and the control samples, at least 3 different wells were analyzed. Wound closure was quantified, measuring five view filed for each well at increasing incubation time, exploiting time lapse videomicroscopy and image analysis, permitting to compare the different healing rate of treatments respect to control. By real-time PCR and western blotting, we evaluated biomarkers of wound regeneration, such as integrins, aquaporin three (AQP3), and proinflammatory cytokines. The ANOVA test was used to assess statistical significance of the results obtained. Laser-treated cells achieved wound closure in about 37 h, faster than the control, while when coupled to HCC, the complete reparation was obtained in 24 h. Integrin αV was upregulated by treatments, with in particular about four-fold increase respect to the control when HCC + laser was used. In addition, integrin ß3 was upregulated by all treatments especially with the combination of laser and HCC proved more efficient than others (~ 14-folds). A slighter but significant increase of AQP3 gene expression of 61% was found for laser treatment while the latter combined with HCC determined an upregulation of 72%. By coupling laser treatment and HCC, further healing improvement and consistent biomarker modulation was observed. Our results may support clinical implementation of new dermatology protocols conjugating laser treatments with topical or injective HA formulations as a valid tool in treatments to repair scars or other skin defects.


Assuntos
Ácido Hialurônico/farmacologia , Queratinócitos/efeitos dos fármacos , Queratinócitos/efeitos da radiação , Lasers de Estado Sólido/uso terapêutico , Cicatrização/efeitos dos fármacos , Biomarcadores/metabolismo , Géis , Humanos , Queratinócitos/citologia , Queratinócitos/metabolismo
14.
Int J Mol Sci ; 22(11)2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34205995

RESUMO

The increasing spread of multidrug-resistant pathogenic bacteria is one of the major threats to public health worldwide. Bacteria can acquire antibiotic resistance and virulence genes through horizontal gene transfer (HGT). A novel horizontal gene transfer mechanism mediated by outer membrane vesicles (OMVs) has been recently identified. OMVs are rounded nanostructures released during their growth by Gram-negative bacteria. Biologically active toxins and virulence factors are often entrapped within these vesicles that behave as molecular carriers. Recently, OMVs have been reported to contain DNA molecules, but little is known about the vesicle packaging, release, and transfer mechanisms. The present review highlights the role of OMVs in HGT processes in Gram-negative bacteria.


Assuntos
Proteínas da Membrana Bacteriana Externa/genética , Membrana Externa Bacteriana/metabolismo , Técnicas de Transferência de Genes , Transferência Genética Horizontal/genética , Bactérias/genética , Bactérias/patogenicidade , Humanos , Fatores de Virulência/genética , Fatores de Virulência/metabolismo
15.
Int J Mol Sci ; 22(16)2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34445438

RESUMO

Gram-negative bacteria release Outer Membrane Vesicles (OMVs) into the extracellular environment. Recent studies recognized these vesicles as vectors to horizontal gene transfer; however, the parameters that mediate OMVs transfer within bacterial communities remain unclear. The present study highlights for the first time the transfer of plasmids containing resistance genes via OMVs derived from Klebsiella pneumoniae (K. pneumoniae). This mechanism confers DNA protection, it is plasmid copy number dependent with a ratio of 3.6 times among high copy number plasmid (pGR) versus low copy number plasmid (PRM), and the transformation efficiency was 3.6 times greater. Therefore, the DNA amount in the vesicular lumen and the efficacy of horizontal gene transfer was strictly dependent on the identity of the plasmid. Moreover, the role of K. pneumoniae-OMVs in interspecies transfer was described. The transfer ability was not related to the phylogenetic characteristics between the donor and the recipient species. K. pneumoniae-OMVs transferred plasmid to Escherichia coli, Salmonella enterica, Pseudomonas aeruginosa and Burkholderia cepacia. These findings address the pivotal role of K. pneumoniae-OMVs as vectors for antimicrobial resistance genes spread, contributing to the development of antibiotic resistance in the microbial communities.


Assuntos
Vesículas Citoplasmáticas/genética , Transferência Genética Horizontal , Klebsiella pneumoniae/genética , Plasmídeos/genética , Antibacterianos/farmacologia , Proteínas de Bactérias , Farmacorresistência Bacteriana , Dosagem de Genes , Klebsiella pneumoniae/classificação , Klebsiella pneumoniae/efeitos dos fármacos , Filogenia
16.
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
17.
Int J Mol Sci ; 21(14)2020 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-32668581

RESUMO

Gastrointestinal (GI) diseases, which include gastrointestinal reflux disease, gastric ulceration, inflammatory bowel disease, and other functional GI disorders, have become prevalent in a large part of the world population. Metabolic syndrome (MS) is cluster of disorders including obesity, hyperglycemia, hyperlipidemia, and hypertension, and is associated with high rate of morbidity and mortality. Gut dysbiosis is one of the contributing factors to the pathogenesis of both GI disorder and MS, and restoration of normal flora can provide a potential protective approach in both these conditions. Bioactive dietary components are known to play a significant role in the maintenance of health and wellness, as they have the potential to modify risk factors for a large number of serious disorders. Different classes of functional dietary components, such as dietary fibers, probiotics, prebiotics, polyunsaturated fatty acids, polyphenols, and spices, possess positive impacts on human health and can be useful as alternative treatments for GI disorders and metabolic dysregulation, as they can modify the risk factors associated with these pathologies. Their regular intake in sufficient amounts also aids in the restoration of normal intestinal flora, resulting in positive regulation of insulin signaling, metabolic pathways and immune responses, and reduction of low-grade chronic inflammation. This review is designed to focus on the health benefits of bioactive dietary components, with the aim of preventing the development or halting the progression of GI disorders and MS through an improvement of the most important risk factors including gut dysbiosis.


Assuntos
Disbiose/complicações , Gastroenteropatias/etiologia , Microbioma Gastrointestinal/fisiologia , Inflamação/etiologia , Síndrome Metabólica/etiologia , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/prevenção & controle , Doença Crônica , Dieta , Gorduras na Dieta/uso terapêutico , Fibras na Dieta/uso terapêutico , Suplementos Nutricionais , Progressão da Doença , Disbiose/dietoterapia , Disbiose/metabolismo , Disbiose/microbiologia , Ácidos Graxos/uso terapêutico , Gastroenteropatias/epidemiologia , Gastroenteropatias/prevenção & controle , Humanos , Inflamação/prevenção & controle , Resistência à Insulina , Síndrome Metabólica/epidemiologia , Síndrome Metabólica/prevenção & controle , Modelos Biológicos , Obesidade/complicações , Obesidade/microbiologia , Estresse Oxidativo , Polifenóis/uso terapêutico , Prebióticos , Probióticos/uso terapêutico , Fatores de Risco , Especiarias
18.
Electromagn Biol Med ; 39(3): 227-238, 2020 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-32447985

RESUMO

Skin aging is primarily associated with the alterations in dermal extracellular matrix, in particular a decrease in collagen type-1 content. Recent studies have shown that collagen-degrading matrix metalloproteinase (MMP-1) is produced by fibroblasts in response to chronoaging, which in human dermal fibroblasts leads to the release of proinflammatory cytokines. Past studies showed that anti-inflammatory capabilities could be induced via non-chemical means. One of these methods makes use of ultra-weak fractal electromagnetic (uwf-EM) signals. Such ultra-/very-low frequency (U/VLF) signals (few nT in intensity and within 0.5-30 kHz) interact with aqueous solutions in living systems. The fractal nature of such EM-signals relates to the self-similar property by which a "cut-out" and magnified piece of this signal reveals again the original. Thus, the aim of this study is twofold, to i) investigate the extent of this modulating effect using Human Dermal Fibroblasts (HDF)-cells, and ii) analyse molecular rejuvenation markers therein. We could demonstrate that a 10 min uwf-EM exposure (prior to incubation) increases type-1 collagen and modulates elastin in human fibroblasts cultured up to 96 h, while at the same time reduces IL-6, TNF-α and MMP-1 (the later three being statistically significant). Such up- respectively down-regulation of corresponding genes are strong indicators of an EM-induced hormetic effect that influences the epigenomic landscape of HDFs. In the Appendix, we present, in the framework of Quantum Field Theory (QFT), water as a biphasic liquid and how its coherent fraction can be affected by uwf-EM signals while at the same time resolving the "kT paradox".


Assuntos
Campos Eletromagnéticos/efeitos adversos , Fibroblastos/metabolismo , Fibroblastos/efeitos da radiação , Fractais , Biomarcadores/metabolismo , Sobrevivência Celular/efeitos da radiação , Colágeno Tipo I/genética , Citocinas/metabolismo , Derme/metabolismo , Derme/efeitos da radiação , Elastina/genética , Fibroblastos/citologia , Regulação Enzimológica da Expressão Gênica/efeitos da radiação , Humanos , Metaloproteinase 1 da Matriz/genética
19.
Lasers Med Sci ; 34(3): 595-605, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30276490

RESUMO

Skin represents an interface between internal and external environment; it protects human body by regulating the water loss and the maintenance of body temperature, defending against irritant and pathogen agents, and against physical, chemical, and UV damage. It provides to essential physiological functions, such as the important antioxidant defense capacity; its protective/defensive function is performed by a high number of proteins, and shows important functions in maintenance of skin barrier homeostasis. Keratinocytes and fibroblasts play a pivotal role to determine or prevent skin aging in response to intrinsic or extrinsic stimuli, modulating cytokines and several biochemical factors. Non-ablative technologies are playing an increasing role in the management of skin aging, inducing a dermal remodeling without a visible epidermal damage. The objective of this study was to evaluate the effect of Q-switched 1064 Nd-YAG laser (Medlite Conbio C6 Nd-YAG laser, Cynosure USA) in skin barrier function, analyzing the constituents which are strongly altered in aging skin. Particularly, we evaluated the expression of filaggrin, TGase, HSP70, and aquaporins, on HaCaT cells. The expression of proinflammatory cytokines has been investigated too.As a second step of the study, we analyzed the modulation of the rejuvenation molecular markers on human skin fibroblasts (HDFs) stimulated with keratinocytes conditioned medium (KCM).Our results demonstrated that Q-switched 1064 nm Nd:YAG laser acts on the skin barrier function, increasing the expression of aquaporins, filaggrin, TGase, and HSP70, modulating the proinflammatory cytokines. In fibroblasts stimulated with keratinocytes conditioned medium (KCM) and irradiated with Q-switched 1064 nm Nd:YAG laser, we can observe a reduction of MMP-1 and an increase in procollagen, collagen type I, and elastin. Our results highlight that Q-switched 1064 nm Nd:YAG laser treatment could represent an effective weapon to fight skin aging.


Assuntos
Biomarcadores/metabolismo , Comunicação Celular , Fibroblastos/efeitos da radiação , Queratinócitos/efeitos da radiação , Lasers de Estado Sólido/uso terapêutico , Rejuvenescimento , Pele/efeitos da radiação , Comunicação Celular/efeitos da radiação , Linhagem Celular , Sobrevivência Celular/efeitos da radiação , Citocinas/genética , Citocinas/metabolismo , Fibroblastos/citologia , Proteínas Filagrinas , Regulação da Expressão Gênica/efeitos da radiação , Humanos , Mediadores da Inflamação/metabolismo , Queratinócitos/citologia , Envelhecimento da Pele/efeitos da radiação , Água
20.
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
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