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1.
Pharmaceuticals (Basel) ; 16(3)2023 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-36986440

RESUMEN

(1) Background: Obesity, a complex metabolic disease resulting from an imbalance between food consumption and energy expenditure, leads to an increase in adipocytes and chronic inflammatory conditions. The aim of this paper was to synthesize a small series of carvacrol derivatives (CD1-3) that are able to reduce both adipogenesis and the inflammatory status often associated with the progression of the obesity disease. (2) Methods: The synthesis of CD1-3 was performed using classical procedures in a solution phase. Biological studies were performed on three cell lines: 3T3-L1, WJ-MSCs, and THP-1. The anti-adipogenic properties of CD1-3 were evaluated using western blotting and densitometric analysis by assessing the expression of obesity-related proteins, such as ChREBP. The anti-inflammatory effect was estimated by measuring the reduction in TNF-α expression in CD1-3-treated THP-1 cells. (3) Results: CD1-3-obtained through a direct linkage between the carboxylic moiety of anti-inflammatory drugs (Ibuprofen, Flurbiprofen, and Naproxen) and the hydroxyl group of carvacrol-have an inhibitory effect on the accumulation of lipids in both 3T3-L1 and WJ-MSCs cell cultures and an anti-inflammatory effect by reducing TNF- α levels in THP-1 cells. (4) Conclusions: Considering the physicochemical properties, stability, and biological data, the CD3 derivative-obtained by a direct linkage between carvacrol and naproxen-resulted in the best candidate, displaying anti-obesity and anti-inflammatory effects in vitro.

2.
Pharmaceutics ; 14(9)2022 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-36145568

RESUMEN

The encapsulation of peptides and proteins in nanosystems has been extensively investigated for masking unfavorable biopharmaceutical properties, including short half-life and poor permeation through biological membranes. Therefore, the aim of this work was to encapsulate a small antimicrobial hydrophilic peptide (H-Ser-Pro-Trp-Thr-NH2, FS10) in PEG-PLGA (polyethylene glycol-poly lactic acid-co-glycolic acid) nanoparticles (Nps) and thereby overcome the common limitations of hydrophilic drugs, which because they facilitate water absorption suffer from rapid degradation. FS10 is structurally related to the well-known RNAIII inhibiting peptide (RIP) and inhibits S. aureus biofilm formation. Various parameters, including different method (double emulsion and nanoprecipitation), pH of the aqueous phase and polymeric composition, were investigated to load FS10 into PEG-PLGA nanoparticles. The combination of different strategies resulted in an encapsulation efficiency of around 25% for both the double emulsion and the nanoprecipitation method. It was found that the most influential parameters were the pH­which tailors the peptides charge­and the polymeric composition. FS10-PEG-PLGA nanoparticles, obtained under optimized parameters, showed size lower than 180 nm with zeta potential values ranging from −11 to −21 mV. In vitro release studies showed that the Nps had an initial burst release of 48−63%, followed by a continuous drug release up to 21 h, probably caused by the porous character of the Nps. Furthermore, transmission electron microscopy (TEM) analysis revealed particles with a spherical morphology and size of around 100 nm. Antimicrobial assay showed that the minimum inhibitory concentration (MIC) of the FS10-loaded Nps, against S. aureus strains, was lower (>128 µg/mL) than that of the free FS10 (>256 µg/mL). The main goal of this work was to develop polymeric drug delivery systems aiming at protecting the peptide from a fast degradation, thus improving its accumulation in the target site and increasing the drug-bacterial membrane interactions.

3.
Int J Mol Sci ; 23(7)2022 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-35408963

RESUMEN

This study evaluates the effects of five different peptides, the Epitalon® tetrapeptide, the Vilon® dipeptide, the Thymogen® dipeptide, the Thymalin® peptide complex, and the Chonluten® tripeptide, as regulators of inflammatory and proliferative processes in the human monocytic THP-1, which is a human leukemia monocytic cell line capable of differentiating into macrophages by PMA in vitro. These peptides (Khavinson Peptides®), characterized by Prof. Khavinson from 1973 onwards, were initially isolated from animal tissues and found to be organ specific. We tested the capacity of the five peptides to influence cell cultures in vitro by incubating THP-1 cells with peptides at certain concentrations known for being effective on recipient cells in culture. We found that all five peptides can modulate key proliferative patterns, increasing tyrosine phosphorylation of mitogen-activated cytoplasmic kinases. In addition, the Chonluten tripeptide, derived from bronchial epithelial cells, inhibited in vitro tumor necrosis factor (TNF) production of monocytes exposed to pro-inflammatory bacterial lipopolysaccharide (LPS). The low TNF release by monocytes is linked to a documented mechanism of TNF tolerance, promoting attenuation of inflammatory action. Therefore, all peptides inhibited the expression of TNF and pro-inflammatory IL-6 cytokine stimulated by LPS on terminally differentiated THP-1 cells. Lastly, by incubating the THP1 cells, treated with the peptides, on a layer of activated endothelial cells (HUVECs activated by LPS), we observed a reduction in cell adhesion, a typical pro-inflammatory mechanism. Overall, the results suggest that the Khavinson Peptides® cooperate as natural inducers of TNF tolerance in monocyte, and act on macrophages as anti-inflammatory molecules during inflammatory and microbial-mediated activity.


Asunto(s)
Lipopolisacáridos , Monocitos , Citocinas/metabolismo , Dipéptidos/farmacología , Células Endoteliales/metabolismo , Humanos , Lipopolisacáridos/metabolismo , Lipopolisacáridos/farmacología , Macrófagos/metabolismo , Monocitos/metabolismo , Células THP-1 , Factor de Necrosis Tumoral alfa/metabolismo
4.
Front Cell Dev Biol ; 8: 607483, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33409282

RESUMEN

Fibrosis is a chronic and progressive disorder characterized by excessive deposition of extracellular matrix, which leads to scarring and loss of function of the affected organ or tissue. Indeed, the fibrotic process affects a variety of organs and tissues, with specific molecular background. However, two common hallmarks are shared: the crucial role of the transforming growth factor-beta (TGF-ß) and the involvement of the inflammation process, that is essential for initiating the fibrotic degeneration. TGF-ß in particular but also other cytokines regulate the most common molecular mechanism at the basis of fibrosis, the Epithelial-to-Mesenchymal Transition (EMT). EMT has been extensively studied, but not yet fully explored as a possible therapeutic target for fibrosis. A deeper understanding of the crosstalk between fibrosis and EMT may represent an opportunity for the development of a broadly effective anti-fibrotic therapy. Here we report the evidences of the relationship between EMT and multi-organ fibrosis, and the possible therapeutic approaches that may be developed by exploiting this relationship.

5.
Curr Urol ; 12(2): 57-63, 2019 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-31114461

RESUMEN

BACKGROUND: The impact of metabolic syndrome on female sexual dysfunction received modest consideration in clinical practice. The aim of the research was to analyze the international literature to determine the relationship between the metabolic syndrome, its components and female sexual disorders. METHODS: We identified relevant full-length papers by electronic databases as Index Medicus/Medline, Scopus, Life Science Journals, from 2005 to the present. Studies were searched using the following as search query: metabolic syndrome, female sexual dysfunction, obesity, systemic arterial hypertension, diabetes mellitus, dyslipidemia. RESULTS: Women with metabolic syndrome showed higher prevalence of sexual inactivity and low sexual desire, orgasm and satisfaction respect to women without metabolic syndrome. Particularly metabolic components as diabetes mellitus, dy-slipidemia, systemic arterial hypertension were strongly associated with lower sexual desire, activity and Female Sexual Function Index total score. In contrast, other studies showed no relationship. CONCLUSION: Our study showed that in the clinical evaluation of women with metabolic syndrome routine inquiring about female sexual dysfunction should be recommended to ameliorate sexual function and quality of life. However more prospective and longitudinal studies on the sexual effects of metabolic syndrome should also be suggested to know the factors related to women's sexuality better.

6.
J Vis Exp ; (146)2019 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-30985753

RESUMEN

The thromboxane A2 receptor (TBXA2R) gene is a member of the G-protein coupled superfamily with seven-transmembrane regions. It is involved in atherogenesis progression, ischemia, and myocardial infarction. Here we present a methodology of patient genotyping to investigate the post-transcriptional role of the C924T polymorphism (rs4523) situated at the 3' region of the TBXA2 receptor gene. This method relies on DNA extraction from whole blood, polymerase chain reaction (PCR) amplification of the TBXA2 gene portion containing the C924T mutation, and identification of wild type and/or mutant genotypes using a restriction digest analysis, specifically a restriction fragment length polymorphism (RFLP) on agarose gel. In addition, the results were confirmed by sequencing the TBXA2R gene. This method features several potential advantages, such as high efficiency and the rapid identification of the C924T polymorphism by PCR and restriction enzyme analysis. This approach allows a predictive study for plaque formation and atherosclerosis progression by analyzing patient genotypes for the TBXA2R C924T polymorphism. Application of this method has the potential to identify subjects who are more susceptible to atherothrombotic processes, in particular subjects in a high-risk, aspirin-treated group.


Asunto(s)
Reacción en Cadena de la Polimerasa/métodos , Polimorfismo de Nucleótido Simple/genética , Receptores de Tromboxano A2 y Prostaglandina H2/genética , Secuencia de Bases , Genotipo , Humanos , Polimorfismo de Longitud del Fragmento de Restricción/genética , Mapeo Restrictivo
7.
Medicina (Kaunas) ; 55(3)2019 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-30866568

RESUMEN

Background: Epidemiological studies suggest a possible relationship between metabolic alterations, cardiovascular disease and aggressive prostate cancer, however, no clear consensus has been reached. Objective: The aim of the study was to analyze the recent literature and summarize our experience on the association between metabolic disorders, aggressive hormone-naïve prostate cancer and cardiovascular disease. Method: We identified relevant papers by searching in electronic databases such as Scopus, Life Science Journals, and Index Medicus/Medline. Moreover, we showed our experience on the reciprocal relationship between metabolic alterations and aggressive prostate cancer, without the influence of hormone therapy, as well the role of coronary and carotid vasculopathy in advanced prostate carcinoma. Results: Prostate cancer cells have an altered metabolic homeostatic control linked to an increased aggressivity and cancer mortality. The absence of discrimination of risk factors as obesity, systemic arterial hypertension, diabetes mellitus, dyslipidemia and inaccurate selection of vascular diseases as coronary and carotid damage at initial diagnosis of prostate cancer could explain the opposite results in the literature. Systemic inflammation and oxidative stress associated with metabolic alterations and cardiovascular disease can also contribute to prostate cancer progression and increased tumor aggressivity. Conclusions: Metabolic alterations and cardiovascular disease influence aggressive and metastatic prostate cancer. Therefore, a careful evaluation of obesity, diabetes mellitus, dyslipidemia, systemic arterial hypertension, together with a careful evaluation of cardiovascular status, in particular coronary and carotid vascular disease, should be carried out after an initial diagnosis of prostatic carcinoma.


Asunto(s)
Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/metabolismo , Enfermedades Metabólicas/epidemiología , Enfermedades Metabólicas/metabolismo , Neoplasias de la Próstata/epidemiología , Neoplasias de la Próstata/metabolismo , Animales , Comorbilidad , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/metabolismo , Dislipidemias/epidemiología , Dislipidemias/metabolismo , Humanos , Hipertensión/epidemiología , Hipertensión/metabolismo , MEDLINE , Masculino , Ratones , Obesidad/epidemiología , Obesidad/metabolismo , Factores de Riesgo
8.
Curr Top Med Chem ; 18(24): 2108-2115, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30526463

RESUMEN

Recently gut bacterial populations seem to be involved in many functions and in the pathogenesis of several medical conditions. Traditionally the intestinal microbiome has been recognized to play an important role in metabolizing food compounds in simpler chemical structures for the absorption of different nutrients, and in maintenance control of gastrointestinal pathogens species. Bacterial populations are implicated in a complicated network of interactions within the immune system, epithelial cells local endocrine system, that affects the peripheral and the central nervous system, via blood circulation. Microbiome influencing the mind via immune, endocrine and metabolic signalling, is able to exert some clinical effects in different mental diseases. It releases endocrine substances through several pathways involved in the modulation of neuroinflammation and production of several neurotrasmitter precursors. It has recently been named psychobiome. It is known that phenolic compounds are able to influence microbiome proliferation and to exert several roles, especially regarding neuroinflammation in depressive and anxious behaviour. The clinical effects are reported in the literature. The aim of this study is to highlight the interaction between polyphenols and microbiota- gut-brain axis.


Asunto(s)
Trastornos de Ansiedad/tratamiento farmacológico , Trastornos de Ansiedad/microbiología , Trastorno Depresivo/tratamiento farmacológico , Trastorno Depresivo/microbiología , Microbioma Gastrointestinal/efectos de los fármacos , Polifenoles/farmacología , Polifenoles/uso terapéutico , Animales , Trastornos de Ansiedad/metabolismo , Trastorno Depresivo/metabolismo , Humanos
9.
PLoS One ; 13(11): e0206894, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30418986

RESUMEN

OBJECTIVE: Obesity is the result of white adipose tissue accumulation where excess of food energy is stored to form triglycerides. De novo lipogenesis (DNL) is the continuous process of new fat production and is driven by the transcription factor ChREBP. During adipogenesis, white adipocytes change their morphology and the entire cell volume is occupied by one large lipid droplet. Recent studies have implicated an essential role of autophagy in adipogenic differentiation, cytoplasmic remodelling and mitochondria reorganization. The phenolic monoterpenoid carvacrol (2-methyl-5-[1-methylethyl]phenol), produced by numerous aromatic plants, has been shown to reduce lipid accumulation in murine 3T3-L1 cells during adipogenic differentiation by modulating genes associated with adipogenesis and inflammation. Therefore, the aim of this study was to evaluate whether carvacrol could affect autophagy and ChREBP expression during adipogenic differentiation. METHODS: The study was carried on by using the murine 3T3-L1 and the human WJ-MSCs (Wharton's jelly-derived mesenchymal stem cells) cell lines. Cells undergoing adipogenic differentiation were untreated or treated with carvacrol. Adipogenic differentiation was assessed by analyzing cellular lipid accumulation with Oil-Red O staining and by ultrastructural examination with TEM. Autophagy was evaluated by western immunoblotting of autophagy markers LC3B and p62/SQSTM and by ultrastructural examination of autophagic bodies. Autophagic flux was evaluated by using autophagy inhibitor cloroquine (CQ). ChREBP expression levels was assessed by both western blotting and immunoelectron microscopy and ChREBP activity by analysis of adipogenic target genes expression. RESULTS: We found that carvacrol reduced adipogenic differentiation of about 40% and 30% in, respectively, 3T3-L1 and in WJ-MSCs cells. The effect of carvacrol on adipogenic differentiation correlated with both reduction of autophagy and reduction of ChREBP expression. CONCLUSION: The results support the notion that carvacrol, through its effect on autophagy (essential for adipocyte maturation) and on ChREBP activity, could be used as a valuable adjuvant to reduce adipogenic differentiation.


Asunto(s)
Adipogénesis/efectos de los fármacos , Autofagia/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Monoterpenos/farmacología , Proteínas Nucleares/metabolismo , Obesidad/tratamiento farmacológico , Factores de Transcripción/metabolismo , Células 3T3-L1 , Adipocitos/efectos de los fármacos , Adipocitos/fisiología , Adipogénesis/fisiología , Animales , Autofagia/fisiología , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice , Línea Celular , Cimenos , Evaluación Preclínica de Medicamentos , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/fisiología , Ratones , Monoterpenos/uso terapéutico , Obesidad/etiología , Cultivo Primario de Células , Gelatina de Wharton/citología
10.
PLoS One ; 10(4): e0120937, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25859852

RESUMEN

OBJECTIVE: The increasing prevalence of antibiotic-resistant bacterial infections led to identify alternative strategies for a novel therapeutic approach. In this study, we synthesized ten carvacrol codrugs - obtained linking the carvacrol hydroxyl group to the carboxyl moiety of sulphur-containing amino acids via an ester bond - to develop novel compounds with improved antimicrobial and antibiofilm activities and reduced toxicity respect to carvacrol alone. METHOD: All carvacrol codrugs were screened against a representative panel of Gram positive (S. aureus and S. epidermidis), Gram negative (E. coli and P. aeruginosa) bacterial strains and C. albicans, using broth microdilution assays. FINDINGS: Results showed that carvacrol codrug 4 possesses the most notable enhancement in the anti-bacterial activity displaying MIC and MBC values equal to 2.5 mg/mL for all bacterial strains, except for P. aeruginosa ATCC 9027 (MIC and MBC values equal to 5 mg/mL and 10 mg/mL, respectively). All carvacrol codrugs 1-10 revealed good antifungal activity against C. albicans ATCC 10231. The cytotoxicity assay showed that the novel carvacrol codrugs did not produce human blood hemolysis at their MIC values except for codrugs 8 and 9. In particular, deepened experiments performed on carvacrol codrug 4 showed an interesting antimicrobial effect on the mature biofilm produced by E. coli ATCC 8739, respect to the carvacrol alone. The antimicrobial effects of carvacrol codrug 4 were also analyzed by TEM evidencing morphological modifications in S. aureus, E. coli, and C. albicans. CONCLUSION: The current study presents an insight into the use of codrug strategy for developing carvacrol derivatives with antibacterial and antibiofilm potentials, and reduced cytotoxicity.


Asunto(s)
Antiinfecciosos/farmacología , Candida albicans/efectos de los fármacos , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Monoterpenos/farmacología , Animales , Antiinfecciosos/química , Antiinfecciosos/toxicidad , Biopelículas/efectos de los fármacos , Candida albicans/fisiología , Cimenos , Eritrocitos/citología , Eritrocitos/efectos de los fármacos , Eritrocitos/metabolismo , Bacterias Gramnegativas/fisiología , Bacterias Grampositivas/fisiología , Hemólisis/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana , Microscopía Electrónica de Transmisión , Monoterpenos/química , Monoterpenos/toxicidad , Ratas
11.
Front Microbiol ; 6: 1369, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26733944

RESUMEN

Helicobacter pylori persistence is associated with its capacity to develop biofilms as a response to changing environmental conditions and stress. Extracellular DNA (eDNA) is a component of H. pylori biofilm matrix but the lack of DNase I activity supports the hypothesis that eDNA might be protected by other extracellular polymeric substances (EPS) and/or Outer Membrane Vesicles (OMVs), which bleb from the bacteria surface during growth. The aim of the present study was to both identify the eDNA presence on OMVs segregated from H. pylori ATCC 43629/NCTC 11639 biofilm (bOMVs) and its planktonic phase (pOMVs) and to characterize the physical-chemical properties of the OMVs. The presence of eDNA in bOMVs and pOMVs was initially carried out using DNase I-gold complex labeling and Transmission Electron Microscope analysis (TEM). bOMVs and pOMVs were further isolated and physical-chemical characterization carried out using dynamic light scattering (DLS) analysis. eDNA associated with OMVs was detected and quantified using a PicoGreen spectrophotometer assay, while its extraction was performed with a DNA Kit. TEM images showed that eDNA was mainly associated with the OMV membrane surfaces; while PicoGreen staining showed a four-fold increase of dsDNA in bOMVs compared with pOMVs. The eDNA extracted from OMVs was visualized using gel electrophoresis. DLS analysis indicated that both planktonic and biofilm H. pylori phenotypes generated vesicles, with a broad distribution of sizes on the nanometer scale. The DLS aggregation assay suggested that eDNA may play a role in the aggregation of OMVs, in the biofilm phenotype. Moreover, the eDNA associated with vesicle membrane may impede DNase I activity on H. pylori biofilms. These results suggest that OMVs derived from the H. pylori biofilm phenotype may play a structural role by preventing eDNA degradation by nucleases, providing a bridging function between eDNA strands on OMV surfaces and promoting aggregation.

12.
FASEB J ; 24(10): 3970-80, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20530751

RESUMEN

Inflammatory lung disease is a primary cause of morbidity and mortality in cystic fibrosis (CF). Mechanisms of unresolved acute inflammation in CF are not completely known, although the involvement of cystic fibrosis transmembrane conductance regulator (CFTR) in nonrespiratory cells is emerging. Here we examined CFTR expression and function in human platelets (PLTs) and found that they express a biologically active CFTR. CFTR blockade gave an ∼50% reduction in lipoxin A(4) (LXA(4)) formation during PLT/polymorphonuclear leukocytes (PMN) coincubations by inhibiting the lipoxin synthase activity of PLT 12-lipoxygenase. PLTs from CF patients generated ∼40% less LXA(4) compared to healthy subject PLTs. CFTR inhibition increased PLT-dependent PMN viability (33.0±5.7 vs. 61.2±8.2%; P=0.033), suppressed nitric oxide generation (0.23±0.04 vs. 0.11±0.002 pmol/10(8) PLTs; P=0.004), while reducing AKT (1.02±0.12 vs. 0.71±0.007 U; P=0.04), and increasing p38 MAPK phosphorylation (0.650±0.09 vs. 1.04±0.24 U; P=0.03). Taken together, these findings indicate that PLTs from CF patients are affected by the molecular defect of CFTR. Moreover, this CF PLT abnormality may explain the failure of resolution in CF.


Asunto(s)
Plaquetas/metabolismo , Regulador de Conductancia de Transmembrana de Fibrosis Quística/sangre , Mediadores de Inflamación/fisiología , Apoptosis , Línea Celular , Femenino , Humanos , Inmunohistoquímica , Masculino , Microscopía Electrónica de Transmisión , Fosforilación , Proteínas Quinasas/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
13.
Bioelectromagnetics ; 29(4): 302-11, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18175330

RESUMEN

To investigate the ability of prokaryotic microorganisms to activate strategies in adapting themselves to the environmental stress induced by exposure to extremely low frequency electromagnetic fields (ELF-EMF), cultures of Escherichia coli ATCC 700926 exposed at 50 Hz EMF (0.1, 0.5, 1.0 mT), and the respective sham-exposed controls were studied for: the total and culturable counts, the viability status, the antimicrobial susceptibility pattern, the morphological analysis, the genotypical and transcriptional profile. Exposed samples and controls displayed similar total and culturable counts, whereas an increased cell viability was observed in exposed samples re-incubated for 24 h outside of the solenoid compared to the corresponding controls. An exposure to 50 Hz EMF of 20-120 min produced a significant change of E. coli morphotype with a presence of coccoid cells also aggregated in clusters after re-incubation of 24 h outside of the solenoid. Atypical lengthened bacterial forms were also observed suggesting a probable alteration during cell division. No changes among DNA fingerprintings and some differences in RNA-AFLP analysis were observed for each 50 Hz EMF intensities evaluated. Our results indicate that an exposure to 50 Hz EMF acts as a stressing factor on bacteria which can represent a suitable model to investigate acute and chronic effects related to ELF-EMF exposure.


Asunto(s)
Tamaño de la Célula/efectos de la radiación , Supervivencia Celular/efectos de la radiación , Electricidad , Campos Electromagnéticos , Proteínas de Escherichia coli/metabolismo , Escherichia coli/fisiología , Escherichia coli/efectos de la radiación , Relación Dosis-Respuesta en la Radiación , Escherichia coli/citología , Dosis de Radiación
14.
FEMS Microbiol Lett ; 241(2): 151-6, 2004 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-15598526

RESUMEN

Peptide methionine sulphoxide reductase (MsrA) and glutathione S-transferases (GSTs) are considered as detoxification enzymes. In the xenobiotics-degrading bacterium Ochrobactrum anthropi the two enzymes are co-induced by toxic concentrations of aromatic substrates such as phenol and 4-chlorophenol. In aerobic organisms, degradation of aromatic substrates by mono- and dioxygenases leads to a generation of oxidative stress that causes the occurrence of reactive oxygen species (ROS). A capillary electrophoretic method, using the intracellular conversion of dihydrorhodamine-123 into rhodamine-123, was developed to measure the content of ROS in the bacteria. The presence of toxic concentrations of the aromatic substrate 4-chlorophenol, an inducer of GST and MsrA, leads to a significant increase in the production of ROS. These results strongly suggest that GST and MsrA enzymes are part of the bacterial defence mechanism against particular oxidative stress conditions. As oxidative stress is known to be present predominantly close to the cytoplasmic membrane, we investigated the subcellular distribution of both MsrA and GST enzymes in this bacterium grown in the presence of 4-chlorophenol. By Western blotting, MsrA and GST was assayed in the cytoplasm as well as in the periplasm. Moreover, immunolocalisation by colloidal gold immunoelectron microscopy identified the two proteins associated with the cell envelope.


Asunto(s)
Clorofenoles/metabolismo , Glutatión Transferasa/metabolismo , Ochrobactrum anthropi/enzimología , Oxidorreductasas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Medios de Cultivo , Metionina Sulfóxido Reductasas , Ochrobactrum anthropi/crecimiento & desarrollo , Fracciones Subcelulares/enzimología
15.
Antimicrob Agents Chemother ; 48(1): 151-60, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14693533

RESUMEN

We investigated the in vitro effects of seven fluoroquinolones (ciprofloxacin, grepafloxacin, levofloxacin, moxifloxacin, norfloxacin, ofloxacin, and rufloxacin), compared to those of trimethoprim-sulfamethoxazole (SXT) and ceftazidime on total biomass and cell viability of Stenotrophomonas maltophilia biofilm. S. maltophilia attached rapidly to polystyrene, within 2 h of incubation, and then biofilm formation increased over time, reaching maximum growth at 24 h. In the presence of fluoroquinolones at one-half and one-fourth the MIC, biofilm biomass was significantly (P < 0.01) reduced to 55 to 70% and 66 to 76% of original mass, respectively. Ceftazidime and SXT did not exert any activity. Biofilm bacterial viability was significantly reduced by all antibiotics tested at one-half the MIC. At one-fourth the MIC all antibiotics, except levofloxacin, significantly reduced viability. Treatment of preformed biofilms with bactericidal concentrations (500, 100, and 50 micro g/ml) of all fluoroquinolones caused, except for norfloxacin, significant reduction of biofilm biomass to 29.5 to 78.8, 64.1 to 83.6, and 70.5 to 82.8% of original mass, respectively. SXT exerted significant activity at 500 micro g/ml only. Ceftazidime was completely inactive. Rufloxacin exhibited the highest activity on preformed biofilm viability, significantly decreasing viable counts by 0.6, 5.4, and 17.1% at 500, 100, and 50 micro g/ml, respectively. Our results show that (i) subinhibitory (one-half and one-fourth the MIC) concentrations of fluoroquinolones inhibit adherence of S. maltophilia to polystyrene and (ii) clinically achievable concentrations (50 and 100 micro g/ml) of rufloxacin are able to eradicate preformed S. maltophilia biofilm.


Asunto(s)
Antiinfecciosos/farmacología , Biopelículas/efectos de los fármacos , Ceftazidima/farmacología , Cefalosporinas/farmacología , Quinolonas/farmacología , Stenotrophomonas maltophilia/efectos de los fármacos , Stenotrophomonas maltophilia/crecimiento & desarrollo , Combinación Trimetoprim y Sulfametoxazol/farmacología , Adhesión Bacteriana/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Microscopía Electrónica , Microscopía Electrónica de Rastreo , Stenotrophomonas maltophilia/ultraestructura
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