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1.
Cells ; 13(7)2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38607083

RESUMO

The neuro-immune axis has a crucial function both during physiological and pathological conditions. Among the immune cells, myeloid-derived suppressor cells (MDSCs) exert a pivotal role in regulating the immune response in many pathological conditions, influencing neuroinflammation and neurodegenerative disease progression. In chronic neuroinflammation, MDSCs could lead to exacerbation of the inflammatory state and eventually participate in the impairment of cognitive functions. To have a complete overview of the role of MDSCs in neurodegenerative diseases, research on PubMed for articles using a combination of terms made with Boolean operators was performed. According to the search strategy, 80 papers were retrieved. Among these, 44 papers met the eligibility criteria. The two subtypes of MDSCs, monocytic and polymorphonuclear MDSCs, behave differently in these diseases. The initial MDSC proliferation is fundamental for attenuating inflammation in Alzheimer's disease (AD), Parkinson's disease (PD), and multiple sclerosis (MS), but not in amyotrophic lateral sclerosis (ALS), where MDSC expansion leads to exacerbation of the disease. Moreover, the accumulation of MDSC subtypes in distinct organs changes during the disease. The proliferation of MDSC subtypes occurs at different disease stages and can influence the progression of each neurodegenerative disorder differently.


Assuntos
Células Supressoras Mieloides , Doenças Neurodegenerativas , Humanos , Células Supressoras Mieloides/patologia , Doenças Neuroinflamatórias , Doenças Neurodegenerativas/patologia , Inflamação/patologia , Proliferação de Células
2.
Chem Biol Interact ; 390: 110895, 2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38301883

RESUMO

Asbestos has been widely used due to its unique characteristics. It is known that exposure to asbestos causes serious damage to health but one species, chrysolite, is still used because it is considered less toxic and not biopersistent in some countries. The aim of our study was to investigate if cellular process underlying the proliferation, differentiation and cell death of placental tissues could be modify in presence of asbestos fibres (50 µg/ml final concentration), long chrysolite fibres (CHR-L) and short chrysolite fibres (CHR-S), using BeWo cell line, an in vitro model that mimics the syncytiotrophoblast (STB), the outer layer of placental villi. Our data demonstrated that none of the fibres analysed alter syncytiotrophoblast formation but all of them induce ROS formation and reduced cell proliferation. Moreover, we showed that only CHR-L fibre induced was able to induce irreversible DNA alterations that carried cells to apoptosis. In fact, BeWo cells exposed to CHR-L fibre showed a significant increase in cleaved CASP3 protein, a marker of apoptosis. These data suggest that CHR-L may induce death of the placental villi leading to impaired placental development. The impairment of placental development is the basis of many gestational pathologies such as preeclampsia and intrauterine growth retardation. Since these pathologies are very dangerous for foetal and maternal life, we suggest to the gynaecologists to carefully evaluate the area of maternal residence, the working environment, the food used, and the materials used daily to avoid contact with these fibres as much as possible.


Assuntos
Amianto , Placenta , Humanos , Gravidez , Feminino , Fibras Minerais/toxicidade , Trofoblastos/metabolismo , Amianto/metabolismo , Amianto/toxicidade , Apoptose
3.
Crit Rev Oncol Hematol ; 194: 104246, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38135018

RESUMO

Non-Small Cell Lung Cancer (NSCLC) represents ∼85% of all lung cancers and ∼15-20% of them are characterized by mutations affecting the Epidermal Growth Factor Receptor (EGFR). For several years now, a class of tyrosine kinase inhibitors was developed, targeting sensitive mutations affecting the EGFR (EGFR-TKIs). To date, the main burden of the TKIs employment is due to the onset of resistance mutations. This scoping review aims to resume the current situation about the cell line models employed for the in vitro evaluation of resistance mechanisms induced by EGFR-TKIs in oncogene-addicted NSCLC. Adenocarcinoma results the most studied NSCLC histotype with the H1650, H1975, HCC827 and PC9 mutated cell lines, while Gefitinib and Osimertinib the most investigated inhibitors. Overall, data collected frame the current advancement of this topic, showing a plethora of approaches pursued to overcome the TKIs resistance, from RNA-mediated strategies to the innovative combination therapies.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB , Linhagem Celular Tumoral , Mutação
5.
Ageing Res Rev ; 61: 101074, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32335301

RESUMO

Epidemiological evidence from observational studies suggests that dietary polyphenols (PPs) - phytochemicals found in a variety of plant-based foods - can reduce the risk of developing type 2 diabetes mellitus (T2DM). Clinical trials have also indicated that PPs may help manage the two key features of T2DM, hyperglycemia and dyslipidemia. Since the incidence of T2DM is dramatically increasing worldwide, identifying food-based approaches that can reduce the risk of developing it and help manage its main risk factors in early-stage disease has clinical and socioeconomic relevance. After a brief overview of current epidemiological data on the incidence of T2DM in individuals consuming PP-rich diets, we review the evidence from clinical trials investigating PP-enriched foods and/or PP-based nutraceutical compounds, report their main results, and highlight the knowledge gaps that should be bridged to enhance our understanding of the role of PPs in T2DM development and management.


Assuntos
Diabetes Mellitus Tipo 2 , Metabolismo Energético/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Polifenóis , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/prevenção & controle , Dieta , Glucose/metabolismo , Humanos , Polifenóis/farmacologia
6.
Eur J Med Chem ; 178: 515-529, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31207463

RESUMO

Carvacrol (CAR), a natural monoterpene particularly abundant in plants belonging to the Lamiaceae family, has recently attracted much attention for its many biological properties (antioxidant, anti-inflammatory, neuroprotective, antitumour, antibacterial, and several others). However, CAR has poor chemical-physical properties (low water solubility and high volatility), which hamper its potential pharmacological uses. In this paper, the synthesis and antimicrobial evaluation of 23 carvacrol derivatives (WSCP1-23) against a panel of selected gram-positive and gram-negative bacteria are reported. Using the prodrug approach, CAR hydrophilic (WSCP1-17) and lipophilic prodrugs (WSCP18-23) were prepared. Notably, CAR water solubility was increased by using polar neutral groups (such as natural amino acids) with the aim of improving oral drug delivery. On the other hand, CAR lipophilic prodrugs, obtained by prenylation of CAR hydroxyl group, were designed to promote membrane permeation and oral absorption. Our results revealed that WSCP1-3, showing the highest water solubility (>1700-fold compared to that of CAR), possessed good antibacterial activity against gram-negative bacteria with MIC values comparable to those of CAR and antifungal properties against different species of Candida. WSCP18-19 were the most promising prodrugs, showing good antibacterial profiles against gram-positive bacteria by interfering with the biofilm formation of Staphylococcus aureus and Staphylococcus epidermidis. Moreover, WSCP18-19 resulted more stable in simulated fluids and human plasma than WSCP1-3. Toxicity studies performed on human erythrocytes and HaCaT cells revealed that all WSCPs were not toxic at the tested concentrations.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Monoterpenos/farmacologia , Pró-Fármacos/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Antifúngicos/síntese química , Antifúngicos/química , Candida/efeitos dos fármacos , Cimenos , Relação Dose-Resposta a Droga , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Monoterpenos/síntese química , Monoterpenos/química , Pró-Fármacos/síntese química , Pró-Fármacos/química , Solubilidade , Relação Estrutura-Atividade
7.
Artigo em Inglês | MEDLINE | ID: mdl-30186775

RESUMO

Anti-virulence strategies are being explored as a novel approach to combat pathogens. Such strategies include inhibition of surface adhesion, tissue invasion, toxin production, and/or interference with the gene regulation of other virulence traits. Listeria monocytogenes, the causative agent of listeriosis, is a facultative intracellular food pathogen characterized by a wide distribution in the environment. Its ability to persist within biofilms and to develop resistance to sanitizers is the cause of significant problems in food processing plants and of steep costs for the food industry. In humans, the treatment of listeriosis is hampered by the intracellular location of listeriae and the poor intracellular penetration of some antibiotics. Eleven L. monocytogenes isolates from patients who were diagnosed with invasive listeriosis in Italy in 2014-2016 were studied. This in vitro and in vivo study explored the antibacterial and anti-virulence properties of a steam-distilled essential oil of Cannabis sativa L., which is being intensively investigated for its high content in powerful bioactive phytochemicals. Susceptibility experiments demonstrated a moderate bactericidal activity of the essential oil (Minimum Bactericidal Concentration > 2048 µg/mL). Assessment of the effects of sublethal concentrations of the essential oil on L. monocytogenes virulence traits demonstrated a significant action on motility. Listeriae were non-motile after exposure to the essential oil. Light and scanning electron microscopy documented aggregates of listeriae with the flagella trapped inside the cluster. Real-time RT-PCR experiments showed downregulation of flagellar motility genes and of the regulatory gene prfA. The ability to form biofilm and to invade Caco-2 cells was also significantly reduced. Galleria mellonella larvae infected with L. monocytogenes grown in presence of sublethal concentrations of the essential oil showed much higher survival rates compared with controls, suggesting that the extract inhibited tissue invasion. Food contamination with L. monocytogenes is a major concern for the food industry, particularly for plants making ready-to-eat and processed food. The present work provides a baseline in the study of the anti-virulence properties of the C. sativa essential oil against L. monocytogenes. Further studies are needed to understand if it could be used as an alternative agent for the control of L. monocytogenes in food processing plants.


Assuntos
Cannabis/química , Listeria monocytogenes/efeitos dos fármacos , Óleos Voláteis/farmacologia , Animais , Bacteriemia/microbiologia , Células CACO-2 , Modelos Animais de Doenças , Endocitose/efeitos dos fármacos , Células Epiteliais/microbiologia , Perfilação da Expressão Gênica , Humanos , Itália , Larva/microbiologia , Larva/fisiologia , Lepidópteros , Listeria monocytogenes/crescimento & desenvolvimento , Listeria monocytogenes/isolamento & purificação , Listeria monocytogenes/patogenicidade , Listeriose/microbiologia , Locomoção/efeitos dos fármacos , Viabilidade Microbiana/efeitos dos fármacos , Microscopia , Microscopia Eletrônica de Varredura , Óleos Voláteis/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sobrevida , Virulência/efeitos dos fármacos
8.
Front Microbiol ; 9: 1378, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29988499

RESUMO

Skin and chronic wound infections are an increasing and urgent health problem worldwide. Their management is difficult and the development of antibiotic resistance by both planktonic and biofilm-associated bacteria necessitates the use of alternative treatments. The purpose of this study was to compare the antimicrobial activity of four honeys from different floral and geographical origins: Melipona beecheii honey (Cuba) and three Apis mellifera honeys [Manuka honey (New Zealand), A. mellifera honey (Cuba), and African honey (Kenya)]. The physicochemical parameters were within the ranges reported for these honeys and M. beecheii honey stood out due to its acidic character. An agar incorporation technique was used to determine the minimum active dilution of each honey against 52 clinical isolates (34 Gram-positive, 17 Gram-negative, and 1 Candida albicans). The antibiofilm activity of honeys was tested by assessing their ability to inhibit biofilm formation and to disrupt preformed biofilms. Overall, M. beecheii honey had the highest antimicrobial and antibiofilm activity, although a marked disruption in preformed biofilms was shared by all tested honeys. Structural changes induced by M. beecheii honey on Staphylococcus aureus and Pseudomonas aeruginosa cells were observed by transmission electron microscopy suggesting that this honey has a potent antimicrobial action and may be an excellent candidate for the development of topical preparations for the treatment of infected wounds.

9.
Microbiol Res ; 210: 43-50, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29625657

RESUMO

The multicellular behavior designated "red dry and rough" (rdar) morphotype-characterized by production of extracellular matrix mainly comprising curli fimbriae and cellulose-is a potential survival strategy of Escherichia coli outside the host. This study documents the ability of Escherichia cryptic clades, which have recently been recognized as new lineages genetically divergent from E. coli, to grow in unfavorable conditions through expression of distinct phenotypes. Growth under low-temperature and nutrient-poor conditions induced the rdar morphotype in all cryptic clade strains tested, especially after preincubation in broth supplemented with uracil. Such phenotypic response to harsh growth conditions was clearly detected by transmission and scanning electron microscopy, which showed that bacteria were encased in a fibrous matrix. Conversely, cells incubated in rich medium at 37 °C showed no matrix. Uracil enhanced the biosynthesis of matrix components, fostering biofilm production and strain adhesion to abiotic surfaces, as demonstrated by the increase of strong biofilm producers in biofilm assays. Harsh growth conditions also induced catalase activity, resulting in clade strain resistance to hydrogen peroxide oxidative stress. The present findings further support the 'environmental hypothesis' whereby cryptic clades would be able to persist in natural habitats outside the host through the expression of distinct survival phenotypes.


Assuntos
Temperatura Baixa , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/fisiologia , Aderência Bacteriana , Proteínas de Bactérias/metabolismo , Técnicas de Tipagem Bacteriana , Biofilmes/crescimento & desenvolvimento , Celulose/metabolismo , Meios de Cultura , Escherichia coli/citologia , Fímbrias Bacterianas/metabolismo , Microscopia Eletrônica de Varredura , Fenótipo
10.
Chemosphere ; 164: 547-557, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27619065

RESUMO

Relevant mineral fibres of social and economic importance (chrysotile UICC, crocidolite UICC and a fibrous erionite from Jersey, Nevada, USA) were put in contact with cultured diploid human non-tumorigenic bronchial epithelial (Beas2B) and pleural transformed mesothelial (MeT5A) cells to test their cytotoxicity. Slides of each sample at different contact times up to 96 h were studied in situ using synchrotron XRF, µ-XRD and µ-XAS (I18 beamline, Diamond Light Source, UK) and TEM investigations. XRF maps of samples treated for 96 h evidenced that iron is still present within the chrysotile and crocidolite fibres and retained at the surface of the erionite fibres, indicating its null to minor mobilization in contact with cell media; this picture was confirmed by the results of XANES pre-edge analyses. µ-XRD and TEM data indicate greater morphological and crystallinity modifications occurring in chrysotile, whereas crocidolite and erionite show to be resistant in the biological environment. The contact of chrysotile with the cell cultures seems to lead to earlier amorphization, interpreted as the first dissolution step of these fibres. The formation of such silica-rich fibre skeleton may prompt the production of HO in synergy with surface iron species and could indicate that chrysotile may be much more reactive and cytotoxic in vitro in the (very) short term whereas the activity of crocidolite and erionite would be much more sluggish but persistent in the long term.


Assuntos
Asbesto Crocidolita/química , Asbestos Serpentinas/química , Ferro/análise , Fibras Minerais/análise , Zeolitas/química , Animais , Asbesto Crocidolita/toxicidade , Asbestos Serpentinas/toxicidade , Brônquios/efeitos dos fármacos , Carcinogênese/induzido quimicamente , Linhagem Celular , Humanos , Ferro/toxicidade , Fibras Minerais/toxicidade , Mucosa Respiratória/efeitos dos fármacos , Zeolitas/toxicidade
11.
Front Microbiol ; 6: 1281, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26617603

RESUMO

Capsaicin (8-methyl-N-vanillyl-6-nonenamide) is the active component of Capsicum plants (chili peppers), which are grown as food and for medicinal purposes since ancient times, and is responsible for the pungency of their fruit. Besides its multiple pharmacological and physiological properties (pain relief, cancer prevention, and beneficial cardiovascular, and gastrointestinal effects) capsaicin has recently attracted considerable attention because of its antimicrobial and anti-virulence activity. This is the first study of its in vitro antibacterial and anti-virulence activity against Streptococcus pyogenes (Group A streptococci, GAS), a major human pathogen. The test strains were previously characterized, erythromycin-susceptible (n = 5) and erythromycin-resistant (n = 27), cell-invasive pharyngeal isolates. The MICs of capsaicin were 64-128 µg/mL (the most common MIC was 128 µg/mL). The action of capsaicin was bactericidal, as suggested by MBC values that were equal or close to the MICs, and by early detection of dead cells in the live/dead assay. No capsaicin-resistant mutants were obtained in single-step resistance selection studies. Interestingly, growth in presence of sublethal capsaicin concentrations induced an increase in biofilm production (p ≤ 0.05) and in the number of bacteria adhering to A549 monolayers, and a reduction in cell-invasiveness and haemolytic activity (both p ≤ 0.05). Cell invasiveness fell so dramatically that a highly invasive strain became non-invasive. The dose-response relationship, characterized by opposite effects of low and high capsaicin doses, suggests a hormetic response. The present study documents that capsaicin has promising bactericidal activity against erythromycin-resistant, cell-invasive pharyngeal GAS isolates. The fact that sublethal concentrations inhibited cell invasion and reduced haemolytic activity, two important virulence traits of GAS, is also interesting, considering that cell-invasive, erythromycinresistant strains can evade ß-lactams by virtue of intracellular location and macrolides by virtue of resistance, thus escaping antibiotic treatment. By inhibiting intracellular invasion and haemolytic activity, capsaicin could thus prevent both formation of a difficult to eradicate intracellular reservoir, and infection spread to deep tissues.

12.
Mutagenesis ; 30(4): 487-97, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25711499

RESUMO

A high risk of neoplastic transformation of nasal and paranasal sinuses mucosa is related to the occupational exposure to wood dust. However, the role of occupational exposures in the aetiology of the airway cancers remains largely unknown. Here, an in vitro model was performed to investigate the carcinogenic effect of wood dusts. Human bronchial epithelial cells were incubated with hard and soft wood dusts and the DNA damage and response to DNA damage evaluated. Wood dust exposure induced accumulation of oxidised DNA bases, which was associated with a delay in DNA repair activity. By exposing cells to wood dust at a prolonged time, wood dust-initiated cells were obtained. Initiated-cells were able to form colonies in soft agar, and to induce blood vessel formation. These cells showed extensive autophagy, reduced DNA repair, which was associated with reduced OGG1 expression and oxidised DNA base accumulation. These events were found related to the activation of EGFR/AKT/mTOR pathway, through phosphorylation and subsequent inactivation of tuberin. The persistence in the tissue of wood dusts, their repetitious binding with EGFR may continually trigger the activation switch, leading to chronic down-regulation of genes involved in DNA repair, leading to cell transformation and proliferation.


Assuntos
Brônquios/patologia , Transformação Celular Neoplásica/patologia , DNA Glicosilases/antagonistas & inibidores , Poeira , Células Epiteliais/patologia , Receptores ErbB/metabolismo , Exposição Ocupacional/efeitos adversos , Madeira/química , Apoptose , Western Blotting , Brônquios/metabolismo , Proliferação de Células , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Células Cultivadas , DNA Glicosilases/genética , DNA Glicosilases/metabolismo , Células Epiteliais/metabolismo , Receptores ErbB/genética , Humanos , Técnicas Imunoenzimáticas , Neovascularização Fisiológica , Fosforilação , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Proteína 2 do Complexo Esclerose Tuberosa , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo
13.
Acta Histochem ; 117(1): 29-39, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25466987

RESUMO

Raw cement asbestos (RCA) undergoes a complete solid state transformation when heated at high temperatures. The secondary raw material produced, high temperatures-cement asbestos (HT-CA) is composed of newly-formed crystals in place of the asbestos fibers present in RCA. Our previous study showed that HT-CA exerts lower cytotoxic cell damage compared to RCA. Nevertheless further investigations are needed to deepen our understanding of pathogenic pathways involving oxidative and nitrative damage. Our aim is to deepen the understanding of the biological effects on A549 cells of these materials regarding DNA damage related proteins (p53, its isoform p73 and TRAIL) and nitric oxide (NO) production during inducible nitric oxide synthase (iNOS)-mediated inflammation. Increments of p53/p73 expression, iNOS positive cells and NO concentrations were found with RCA, compared to HT-CA and controls mainly at 48 h. Interestingly, ferrous iron causing reactive oxygen species (ROS)-mediated DNA damage was found in RCA as a contaminant. HT-CA thermal treatment induces a global recrystallization with iron in a crystal form poorly released in media. HT-CA slightly interferes with genome expression and exerts lower inflammatory potential compared to RCA on biological systems. It could represent a safe approach for storing or recycling asbestos and an environmentally friendly alternative to asbestos waste.


Assuntos
Amianto/toxicidade , Citotoxinas/toxicidade , Dano ao DNA , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/biossíntese , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Óxido Nítrico/biossíntese , Proteínas Nucleares/biossíntese , Espécies Reativas de Oxigênio/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/biossíntese , Proteína Tumoral p73 , Proteína Supressora de Tumor p53/biossíntese , Proteínas Supressoras de Tumor/biossíntese
14.
Free Radic Biol Med ; 67: 451-9, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24333633

RESUMO

The mitochondrial pool of GSH (glutathione) is considered the major redox system in maintaining matrix redox homeostasis, preserving sulfhydryl groups of mitochondrial proteins in appropriate redox state, in defending mitochondrial DNA integrity and protecting mitochondrial-derived ROS, and in defending mitochondrial membranes against oxidative damage. Despite its importance in maintaining mitochondrial functionality, GSH is synthesized exclusively in the cytoplasm and must be actively transported into mitochondria. In this work we found that SLG (S-D-lactoylglutathione), an intermediate of the glyoxalase system, can enter the mitochondria and there be hydrolyzed from mitochondrial glyoxalase II enzyme to D-lactate and GSH. To demonstrate SLG transport from cytosol to mitochondria we used radiolabeled compounds and the results showed two different kinetic curves for SLG or GSH substrates, indicating different kinetic transport. Also, the incubation of functionally and intact mitochondria with SLG showed increased GSH levels in normal mitochondria and in artificially uncoupled mitochondria, demonstrating transport not linked to ATP presence. As well mitochondrial-swelling assay confirmed SLG entrance into organelles. Moreover we observed oxygen uptake and generation of membrane potential probably linked to D-lactate oxidation which is a product of SLG hydrolysis. The latter data were confirmed by oxidation of D-lactate in mitochondria evaluated by measuring mitochondrial D-lactate dehydrogenize activity. In this work we also showed the presence of mitochondrial glyoxalase II in inter-membrane space and mitochondrial matrix and we investigated the role of SLG in whole cells. In conclusion, this work showed new alternative sources of GSH supply to the mitochondria by SLG, an intermediate of the glyoxalase system.


Assuntos
Glutationa/análogos & derivados , Glutationa/metabolismo , Mitocôndrias Hepáticas/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Transporte Biológico , Radioisótopos de Carbono , Citosol/metabolismo , Glutationa/farmacologia , Cinética , Lactato Desidrogenases , Ácido Láctico/biossíntese , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias Hepáticas/efeitos dos fármacos , Oxirredução , Estresse Oxidativo , Ratos , Ratos Wistar , Tioléster Hidrolases/metabolismo , Trítio
15.
Brain Res Bull ; 99: 48-62, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24107244

RESUMO

The distribution, colocalization with enzymes producing nitric oxide (NO), and the synaptic organization of neurons containing two calcium-binding proteins (CaBPs) - parvalbumin (Parv) and calbindin-D28K (Calb) - were investigated in the rat periaqueductal gray matter (PAG). Parv-immunopositive (ParvIP) neurons were detected in the mesencephalic nucleus and rarely in the PAG. CalbIP neurons were found both in the dorsolateral (PAG-dl) and ventrolateral PAG (PAG-vl); their size ranged from 112.96 µm(2) (PAG-dl) to 125.13 µm(2) (PAG-vl). Ultrastructurally Parv and Calb immunoreactivity was mostly found in dendritic profiles. Axon terminals containing each of the two CaBPs formed symmetric synapses. Moreover both Parv and Calb were used to label a subpopulation of NO-producing neurons. Colocalization was investigated using two protocols: (i) a combination of Calb and Parv immunocytochemistry (Icc) with nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-d) histochemistry (Hi) and (ii) neuronal NO synthase-Icc (nNOS) (immunofluorescence). Both techniques demonstrated a complete lack of colocalization of Parv and NADPH-d/nNOS in PAG neurons. Double-labeled (DL) neurons (Calb-NADPH-d; Calb-nNOS) were detected in PAG-dl. NADPH-d-Hi/Calb-Icc indicated that 41-47% of NADPH-d-positive neurons contained Calb, whereas 17-23% of CalbIP cells contained NADPH-d. Two-color immunofluorescence revealed that 53-66% of nNOSIP cells colocalized with Calb and 24-34% of CalbIP neurons contained nNOS. DL neuron size was 104.44 µm(2); neurons labeled only with NADPH-d or Calb measured 89.793 µm(2) and 113.48 µm(2), respectively. Together with previous findings (Barbaresi et al. [2012]) these data suggest that: Therefore the important aspect of the PAG intrinsic organization emerging from this and previous double-labeling studies is the chemical diversity of NO-synthesizing neurons, which is likely related to the different functions in which these neurons are involved.


Assuntos
Calbindina 1/metabolismo , Neurônios/metabolismo , Óxido Nítrico Sintase Tipo I/metabolismo , Parvalbuminas/metabolismo , Substância Cinzenta Periaquedutal/citologia , Animais , Calbindina 1/ultraestrutura , Contagem de Células , Masculino , Microscopia Imunoeletrônica , NADP/metabolismo , NADP/ultraestrutura , Neurônios/ultraestrutura , Óxido Nítrico Sintase Tipo I/ultraestrutura , Parvalbuminas/ultraestrutura , Substância Cinzenta Periaquedutal/metabolismo , Ratos , Ratos Sprague-Dawley
16.
Acta Histochem ; 115(2): 100-12, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22578742

RESUMO

Mineral fibers are potential carcinogens to humans. In order to help clarify the etiology of the pathological effects of asbestos, cellular reactions to natural and synthetic asbestos fibers were compared using a lung alveolar cancer cell line (A549 epithelial cells), considered the first target of inhaled micro-environmental contaminants. Natural asbestos tremolite (NAT) fibers were collected from rocks in NW Italy. Synthetic asbestos tremolite (SAT) was iron-free and therefore considered as standard tremolite. Both fibers, subjected to mineralogical characterization by X-ray powder diffractometry, electron microscopy and energy dispersive spectrometry, fell within the definition of respirable and potentially carcinogenic fibers. Several signs of functional and structural cell damage were found after treatment with both fibers, documented by viability, motility, and morphological perturbations. Phalloidin labeling showed irregular distribution of cytoskeletal F-actin, whereas immunohistochemical investigations showed abnormal expression of VEGF, Cdc42, ß-catenin, assessed as risks indicators for cancer development. Both fibers caused significant loss of viability, even compared to UICC crocidolite, but, while SAT fibers exerted a more direct cytotoxic effect, survival of damaged cells expressing high VEGF levels was detected after NAT contact. This in vitro pilot study outlines potential health risks of NAT fibers in vivo related to their iron content, which could trigger signaling networks connected with cell proliferation and neoplastic transformation.


Assuntos
Amiantos Anfibólicos/toxicidade , Amianto/toxicidade , Actinas/metabolismo , Apoptose , Asbesto Crocidolita/toxicidade , Linhagem Celular Tumoral , Sobrevivência Celular , Citoesqueleto/metabolismo , Humanos , Imuno-Histoquímica , Ferro/química , Microscopia Eletrônica , Mitose , Necrose , Faloidina/química , Projetos Piloto , Sais de Tetrazólio/farmacologia , Tiazóis/farmacologia , Fatores de Tempo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Raios X , beta Catenina/metabolismo , Proteína cdc42 de Ligação ao GTP/metabolismo
17.
Anal Bioanal Chem ; 402(2): 871-81, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22057722

RESUMO

Chemical reactivity of asbestos tremolite from Italy and USA localities and Union Internationale Contre le Cancer (UICC) crocidolite was studied in relation to Fe content, oxidation state, and structural coordination. Direct correlation between amount of Fe(2+) at the exposed M(1) and M(2) sites of the amphibole structure and fiber chemical reactivity was established. The in vitro toxicity of the same samples was investigated on human alveolar A549 cell line. Relationship between crystal-chemical features and cell toxicity is not straightforward. UICC crocidolite has Fe content and chemical reactivity largely higher than that of tremolite samples, but all show comparable in vitro toxic potential. Results obtained evidenced that Fe topochemistry is not a primary factor for induced cell toxicity, though it accounts for asbestos chemical reactivity (and possibly genotoxicity).


Assuntos
Amiantos Anfibólicos/química , Amiantos Anfibólicos/toxicidade , Compostos Ferrosos/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Relação Estrutura-Atividade , Propriedades de Superfície
18.
PLoS One ; 7(12): e52151, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23284910

RESUMO

H-Ras oncogene requires deregulation of additional oncogenes or inactivation of tumor suppressor proteins to increase cell proliferation rate and transform cells. In fact, the expression of the constitutively activated H-RasV12 induces cell growth arrest and premature senescence, which act like barriers in pre-neoplastic lesions. In our experimental model, human fibroblasts transfected with H-RasV12 show a dramatic modification of morphology. H-RasV12 expressing cells also show premature senescence followed by cell death, induced by autophagy and apoptosis. In this context, we provide evidence that in H-RasV12 expressing cells, the premature senescence is associated with cellular redox imbalance as well as with altered post-translation protein modification. In particular, redox imbalance is due to a strong reduction of total antioxidant capacity, and significant decrease of glutathione level. As the reversible addition of glutathione to cysteinyl residues of proteins is an important post-translational regulative modification, we investigated S-glutathionylation in cells expressing active H-Ras. In this contest we observed different S-glutathionylation patterns in control and H-RasV12 expressing cells. Particularly, the GAPDH enzyme showed S-glutathionylation increase and significant enzyme activity depletion in H-Ras V12 cells. In conclusion, we proposed that antioxidant defense reduction, glutathione depletion and subsequent modification of S-glutathionylation of target proteins contribute to arrest cell growth, leading to death of fibroblasts expressing constitutively active H-Ras oncogene, thus acting as oncogenic barriers that obstacle the progression of cell transformation.


Assuntos
Autofagia/fisiologia , Senescência Celular/fisiologia , Genes ras/fisiologia , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/genética , Apoptose/fisiologia , Autofagia/efeitos dos fármacos , Autofagia/genética , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Ciclo Celular/fisiologia , Morte Celular/efeitos dos fármacos , Morte Celular/genética , Morte Celular/fisiologia , Linhagem Celular , Senescência Celular/efeitos dos fármacos , Senescência Celular/genética , Eletroforese em Gel Bidimensional , Genes ras/genética , Humanos , Immunoblotting , Espectrometria de Massas , Oxirredução , Espécies Reativas de Oxigênio/metabolismo
19.
Artigo em Inglês | MEDLINE | ID: mdl-21320627

RESUMO

In fast growing organisms, like fish larvae, fatty acids provided through live prey are essential to satisfy high energy demand and are required to promote growth. Therefore, in recent decades, a great amount of research has been directed towards the development of lipid enrichment in order to improve larval fish survival and growth. However, in fish, the biochemical and molecular processes related to highly unsaturated fatty acid (HUFA) administration are still poorly understood. In the current study, the false percula clownfish, a short larval phase marine species, was used as an experimental model and the effects of a standard and a HUFAs-enriched diet were tested through a molecular, biochemical, ultrastructural and morphometric approach. Our results support the hypothesis that HUFA administration may improve larval development through the presence of better structured mitochondria, a higher synthesis of energy compounds and coenzymes with a central position in the metabolism, with respect to controls. This higher energy status was confirmed by better growth performance and a shorter larval phase in larvae fed with an enriched diet with respect to the control. This strategy of rapid growth and early energy storage may be considered positively adaptive and beneficial to the survival of this species.


Assuntos
Ácidos Graxos Insaturados/administração & dosagem , Peixes/fisiologia , Larva/crescimento & desenvolvimento , Metamorfose Biológica , Comportamento Predatório , Animais , Sequência de Bases , Primers do DNA , Peixes/genética , Peixes/crescimento & desenvolvimento , Humanos , Metabolismo dos Lipídeos , Reação em Cadeia da Polimerase , Análise de Sobrevida , Hormônios Tireóideos/metabolismo
20.
Toxicol In Vitro ; 24(6): 1521-31, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20637854

RESUMO

Asbestos fibres can be transformed into potentially non-hazardous silicates by high-temperature treatment via complete solid-state transformation. A549 cells were exposed to standard concentrations of raw cement asbestos (RCA), chrysotile and cement asbestos subjected to an industrial process at 1200 degrees C (Cry_1200 and KRY.AS, respectively), raw commercial grey cement (GC). Cell growth rate and viability (MTT test) were detected in vitro. RCA and KRY.AS subjected to comprehensive microstructural study by electron microscopy were further in vitro assayed to compare their cytotoxic potential by morphostructural studies, proliferation index (Ki-67 antigen), apoptosis induction (AO/EB staining) assays and detection of intracellular reactive oxygen species (ROS) with the fluorescent DCFA dye. More severe cytotoxic damage was induced by RCA than by KRY.AS after each incubation period. Exposure to KRY.AS and GC resulted in comparable cell growth rates and cytotoxic effects. Cells incubated with RCA showed greater apoptotic induction and ROS production and a lower cell proliferation index than those exposed to KRY.AS. Chrysotile asbestos and RCA subjected to heat treatment underwent complete microstructure transformation. The final product of heat treatment of cement asbestos, KRY.AS, was considerably more inert and had lower cytotoxic potential than the original asbestos material in all in vitro tests.


Assuntos
Células Epiteliais Alveolares/efeitos dos fármacos , Asbestos Serpentinas/toxicidade , Cerâmica , Materiais de Construção/efeitos adversos , Temperatura Alta , Células Epiteliais Alveolares/metabolismo , Células Epiteliais Alveolares/patologia , Apoptose/efeitos dos fármacos , Asbestos Serpentinas/química , Asbestos Serpentinas/isolamento & purificação , Linhagem Celular Transformada , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Materiais de Construção/análise , Humanos , Antígeno Ki-67/metabolismo , Microscopia Eletrônica de Varredura , Espécies Reativas de Oxigênio/metabolismo , Sais de Tetrazólio/metabolismo , Tiazóis/metabolismo
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