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1.
Curr Issues Mol Biol ; 46(6): 5999-6017, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38921029

RESUMO

Amyotrophic lateral sclerosis (ALS) represents a neurodegenerative disorder characterized by the progressive loss of both upper and lower motor neurons, resulting in muscular atrophy and eventual paralysis. While much research has concentrated on investigating the impact of major mutations associated with ALS on motor neurons and central nervous system (CNS) cells, recent studies have unveiled that ALS pathogenesis extends beyond CNS imbalances, encompassing dysregulation in other tissues such as skeletal muscle. Evidence from animal models and patients supports this broader perspective. Skeletal muscle, once considered solely as an effector organ, is now recognized as possessing significant secretory activity capable of influencing motor neuron survival. However, the precise cellular and molecular mechanisms underlying the detrimental effects observed in muscle and its associated structures in ALS remain poorly understood. Additionally, emerging data suggest that extracellular vesicles (EVs) may play a role in the establishment and function of the neuromuscular junction (NMJ) under both physiological and pathological conditions and in wasting and regeneration of skeletal muscles, particularly in neurodegenerative diseases like ALS. This review aims to explore the key findings about skeletal muscle involvement in ALS, shedding light on the potential underlying mechanisms and contributions of EVs and their possible application for the design of biosensors.

2.
Int J Mol Sci ; 25(13)2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38999977

RESUMO

Growing evidence identifies extracellular vesicles (EVs) as important cell-to-cell signal transducers in autoimmune disorders, including multiple sclerosis (MS). If the etiology of MS still remains unknown, its molecular physiology has been well studied, indicating peripheral blood mononuclear cells (PBMCs) as the main pathologically relevant contributors to the disease and to neuroinflammation. Recently, several studies have suggested the involvement of EVs as key mediators of neuroimmune crosstalk in central nervous system (CNS) autoimmunity. To assess the role of EVs in MS, we applied electron microscopy (EM) techniques and Western blot analysis to study the morphology and content of plasma-derived EVs as well as the ultrastructure of PBMCs, considering four MS patients and four healthy controls. Through its exploratory nature, our study was able to detect significant differences between groups. Pseudopods and large vesicles were more numerous at the plasmalemma interface of cases, as were endoplasmic vesicles, resulting in an activated aspect of the PBMCs. Moreover, PBMCs from MS patients also showed an increased number of multivesicular bodies within the cytoplasm and amorphous material around the vesicles. In addition, we observed a high number of plasma-membrane-covered extensions, with multiple associated large vesicles and numerous autophagosomal vacuoles containing undigested cytoplasmic material. Finally, the study of EV cargo evidenced a number of dysregulated molecules in MS patients, including GANAB, IFI35, Cortactin, Septin 2, Cofilin 1, and ARHGDIA, that serve as inflammatory signals in a context of altered vesicular dynamics. We concluded that EM coupled with Western blot analysis applied to PBMCs and vesiculation can enhance our knowledge in the physiopathology of MS.


Assuntos
Vesículas Extracelulares , Leucócitos Mononucleares , Esclerose Múltipla , Humanos , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/ultraestrutura , Leucócitos Mononucleares/metabolismo , Esclerose Múltipla/patologia , Esclerose Múltipla/metabolismo , Projetos Piloto , Feminino , Adulto , Masculino , Pessoa de Meia-Idade
3.
Int J Mol Sci ; 24(14)2023 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-37511010

RESUMO

Neuroinflammation is a common pathological feature of amyotrophic lateral sclerosis (ALS). Although scientific evidence to date does not allow defining neuroinflammation as an ALS trigger, its role in exacerbating motor neuron (MNs) degeneration and disease progression is attracting research interest. Activated CNS (Central Nervous System) glial cells, proinflammatory peripheral and infiltrated T lymphocytes and monocytes/macrophages, as well as the immunoreactive molecules they release, represent the active players for the role of immune dysregulation enhancing neuroinflammation. The crosstalk between the peripheral and CNS immune cells significantly correlates with the survival of ALS patients since the modification of peripheral macrophages can downregulate inflammation at the periphery along the nerves and in the CNS. As putative vehicles for misfolded protein and inflammatory mediators between cells, extracellular vesicles (EVs) have also drawn particular attention in the field of ALS. Both CNS and peripheral immune cells release EVs, which are able to modulate the behavior of neighboring recipient cells; unfortunately, the mechanisms involved in EVs-mediated communication in neuroinflammation remain unclear. This review aims to synthesize the current literature regarding EV-mediated cell-to-cell communication in the brain under ALS, with a particular point of view on the role of peripheral macrophages in responding to inflammation to understand the biological process and exploit it for ALS management.


Assuntos
Esclerose Lateral Amiotrófica , Vesículas Extracelulares , Humanos , Esclerose Lateral Amiotrófica/metabolismo , Doenças Neuroinflamatórias , Macrófagos/metabolismo , Inflamação/metabolismo , Vesículas Extracelulares/metabolismo
4.
Int J Mol Sci ; 21(21)2020 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-33171763

RESUMO

Extracellular vesicles (EVs) are widely investigated in glioblastoma multiforme (GBM) for their involvement in regulating GBM pathobiology as well as for their use as potential biomarkers. EVs, through cell-to-cell communication, can deliver proteins, nucleic acids, and lipids that are able to reprogram tumor-associated macrophages (TAMs). This research is aimed to concentrate, characterize, and identify molecular markers of EVs subtypes released by temozolomide (TMZ)-treated and non TMZ-treated four diverse GBM cells. Morphology, size distribution, and quantity of small (sEVs) and large (lEVs) vesicles were analyzed by cryo-TEM. Quality and quantity of EVs surface markers were evaluated, having been obtained by Western blotting. GBM cells shed a large amount of EVs, showing a cell line dependent molecular profile A comparative analysis distinguished sEVs and lEVs released by temozolomide (TMZ)-treated and non TMZ-treated GBM cells on the basis of quantity, size and markers expression. Finally, the GBM-derived sEVs and lEVs, irrespective of TMZ treatment, when challenged with macrophages, modulated cell activation toward a tendentially M2b-like phenotype.


Assuntos
Vesículas Extracelulares/efeitos dos fármacos , Ativação de Macrófagos/efeitos dos fármacos , Temozolomida/farmacologia , Linhagem Celular Tumoral , Microscopia Crioeletrônica/métodos , Resistencia a Medicamentos Antineoplásicos/genética , Exossomos/metabolismo , Vesículas Extracelulares/metabolismo , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Humanos , Ativação de Macrófagos/fisiologia , Macrófagos/metabolismo , MicroRNAs/genética , Temozolomida/metabolismo
5.
Int J Mol Sci ; 19(5)2018 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-29702561

RESUMO

Medicine, food, and cosmetics represent the new promising applications for silver (Ag) and gold (Au) nanoparticles (NPs). AgNPs are most commonly used in food and cosmetics; conversely, the main applications of gold NPs (AuNPs) are in the medical field. Thus, in view of the risk of accidentally or non-intended uptake of NPs deriving from the use of cosmetics, drugs, and food, the study of NPs⁻cell interactions represents a key question that puzzles researchers in both the nanomedicine and nanotoxicology fields. The response of cells starts when the NPs bind to the cell surface or when they are internalized. The amount and modality of their uptake depend on many and diverse parameters, such as NPs and cell types. Here, we discuss the state of the art of the knowledge and the uncertainties regarding the biological consequences of AgNPs and AuNPs, focusing on NPs cell uptake, location, and translocation. Finally, a section will be dedicated to the most currently available methods for qualitative and quantitative analysis of intracellular transport of metal NPs.


Assuntos
Endocitose , Ouro/metabolismo , Ouro/toxicidade , Prata/metabolismo , Prata/toxicidade , Animais , Transporte Biológico , Cosméticos , Alimentos , Ouro/análise , Ouro/química , Humanos , Lisossomos/química , Nanopartículas Metálicas/química , Modelos Animais , Nanomedicina , Medicina do Trabalho , Tamanho da Partícula , Prata/análise , Prata/química
6.
Biomedicines ; 12(9)2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39335582

RESUMO

Microglia-mediated neuroinflammation is a key player in the pathogenesis of amyotrophic lateral sclerosis (ALS) as it can contribute to the progressive degeneration of motor neurons (MNs). Here, we investigated the role of mSOD1 NSC-34 MN-like cell-derived extracellular vesicles (EVs) in inducing the activation of BV2 microglial cells. NSC-34-released EVs were isolated by culture medium differential ultracentrifugation to obtain two fractions, one containing small EVs (diameter < 200 nm) and the other containing large EVs (diameter > 200 nm). BV2 cells were incubated with the two EV fractions for 12, 24, and 48 h to evaluate 1) the state of microglial inflammation through RT-PCR of IL-1ß, IL-6, IL-4, and IL-10 and 2) the expression of proteins involved in inflammasome activation (IL-ß and caspase 1), cell death (caspase 3), and glial cell recruitment (CXCR1), and presence of the TGFß cytokine receptor (TGFß-R2). The obtained results suggest a mSOD1 type-dependent polarization of BV2 cells towards an early neurotoxic phenotype and a late neuroprotective status, with an appearance of mixed M1 and M2 microglia subpopulations. A significant role in driving microglial cell activation is played by the TGFß/CX3CR1 axis. Therefore, targeting the dysregulated microglial response and modulating neuroinflammation could hold promise as a therapeutic strategy for ALS.

7.
Pharmaceutics ; 16(7)2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39065629

RESUMO

Cancer remains a significant global health challenge, with traditional therapies like surgery, chemotherapy, and radiation often accompanied by systemic toxicity and damage to healthy tissues. Despite progress in treatment, these approaches have limitations such as non-specific targeting, systemic toxicity, and resistance development in cancer cells. In recent years, nanotechnology has emerged as a revolutionary frontier in cancer therapy, offering potential solutions to these challenges. Nanoparticles, due to their unique physical and chemical properties, can carry therapeutic payloads, navigate biological barriers, and selectively target cancer cells. Metal-based nanoparticles, in particular, offer unique properties suitable for various therapeutic applications. Recent advancements have focused on the integration of metal-based nanoparticles to enhance the efficacy and precision of photodynamic therapy. Integrating nanotechnology into cancer therapy represents a paradigm shift, enabling the development of strategies with enhanced specificity and reduced off-target effects. This review aims to provide a comprehensive understanding of the pivotal role of metal-based nanoparticles in photodynamic therapy. We explore the mechanisms, biocompatibility, and applications of metal-based nanoparticles in photodynamic therapy, highlighting the challenges and the limitations in their use, as well as the combining of metal-based nanoparticles/photodynamic therapy with other strategies as a synergistic therapeutic approach for cancer treatment.

8.
Genes (Basel) ; 15(6)2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38927671

RESUMO

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease targeting the brain and spinal cord. Non-neuronal cells, including macrophages, may contribute to the disruption of motor neurons (MNs), neuromuscular junction dismantling and clinical signs of ALS. Understanding the modality and the effect of MNs-macrophage communication is pivotal. Here, we focus on extracellular vesicle (EVS)-mediated communication and, in particular, we analyze the response of macrophages. NSC-34 cells transfected with mutant SOD1 (G93A, A4V, G85R, G37R) and differentiated towards MN-like cells, and Raw 264.7 macrophages are the cellular models of the study. mSOD1 NSC-34 cells release a high number of vesicles, both large-lEVs (300 nm diameter) and small-sEVs (90 nm diameter), containing inflammation-modulating molecules, and are efficiently taken up by macrophages. RT-PCR analysis of inflammation mediators demonstrated that the conditioned medium of mSOD1 NSC-34 cells polarizes Raw 264.7 macrophages towards both pro-inflammatory and anti-inflammatory phenotypes. sEVs act on macrophages in a time-dependent manner: an anti-inflammatory response mediated by TGFß firstly starts (12 h); successively, the response shifts towards a pro-inflammation IL-1ß-mediated (48 h). The response of macrophages is strictly dependent on the SOD1 mutation type. The results suggest that EVs impact physiological and behavioral macrophage processes and are of potential relevance to MN degeneration.


Assuntos
Esclerose Lateral Amiotrófica , Vesículas Extracelulares , Macrófagos , Neurônios Motores , Superóxido Dismutase-1 , Animais , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/genética , Camundongos , Células RAW 264.7 , Superóxido Dismutase-1/genética , Superóxido Dismutase-1/metabolismo , Macrófagos/metabolismo , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/patologia , Neurônios Motores/metabolismo , Inflamação/genética , Inflamação/metabolismo , Inflamação/patologia , Mutação , Transfecção , Humanos
9.
Int J Syst Evol Microbiol ; 63(Pt 1): 72-79, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22328613

RESUMO

Strain SPC-1(T) was isolated from the phyllosphere of Cynara cardunculus L. var. sylvestris (Lamk) Fiori (wild cardoon), a Mediterranean native plant considered to be the wild ancestor of the globe artichoke and cultivated cardoon. This Gram-stain-negative, catalase-positive, oxidase-negative, non-spore-forming, rod-shaped and non-motile strain secreted copious amounts of an exopolysaccharide, formed slimy, viscous, orange-pigmented colonies and grew optimally at around pH 6.0-6.5 and 26-30 °C in the presence of 0-0.5 % NaCl. Phylogenetic analysis based on comparisons of 16S rRNA gene sequences demonstrated that SPC-1(T) clustered together with species of the genus Sphingomonas sensu stricto. The G+C content of the DNA (66.1 mol%), the presence of Q-10 as the predominant ubiquinone, sym-homospermidine as the predominant polyamine, 2-hydroxymyristic acid (C(14 : 0) 2-OH) as the major hydroxylated fatty acid, the absence of 3-hydroxy fatty acids and the presence of sphingoglycolipid supported this taxonomic position. 16S rRNA gene sequence analysis showed that SPC-1(T) was most closely related to Sphingomonas hankookensis ODN7(T), Sphingomonas insulae DS-28(T) and Sphingomonas panni C52(T) (98.19, 97.91 and 97.11 % sequence similarities, respectively). However, DNA-DNA hybridization analysis did not reveal any relatedness at the species level. Further differences were apparent in biochemical traits, and fatty acid, quinone and polyamine profiles leading us to conclude that strain SPC-1(T) represents a novel species of the genus Sphingomonas, for which the name Sphingomonas cynarae sp. nov. is proposed; the type strain is SPC-1(T) ( = JCM 17498(T) = ITEM 13494(T)). A component analysis of the exopolysaccharide suggested that it represents a novel type of sphingan containing glucose, rhamnose, mannose and galactose, while glucuronic acid, which is commonly found in sphingans, was not detected.


Assuntos
Cynara/microbiologia , Filogenia , Polissacarídeos Bacterianos/biossíntese , Sphingomonas/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/análise , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Poliaminas/análise , RNA Ribossômico 16S/genética , Sphingomonas/genética , Sphingomonas/isolamento & purificação , Ubiquinona/análise
10.
Nanotechnology ; 23(49): 495104, 2012 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-23165288

RESUMO

A surprising and unexpected biomineralization process was observed during toxicological assessment of carbon nanoparticles on Paracentrotus lividus (sea urchin) pluteus larvae. The larvae activate a process of defense against external material, by incorporating the nanoparticles into microstructures of aragonite similarly to pearl oysters. Aiming at a better understanding of this phenomenon, the larvae were exposed to increasing concentrations of carbon nanoparticles and the biomineralization products were analyzed by electron microscopy, x-ray diffraction and Raman spectroscopy. In order to evaluate the possible influence of Sp-CyP-1 expression on this biomineralization process by larvae, analyses of gene expression (Sp-CyP-1) and calcein labeling were performed. Overall, we report experimental evidence about the capability of carbon nanoparticles to induce an increment of Sp-CyP-1 expression with the consequent activation of a biomineralization process leading to the production of a new pearl-like biomaterial never previously observed in sea urchins.


Assuntos
Minerais/metabolismo , Nanotubos de Carbono/toxicidade , Paracentrotus/efeitos dos fármacos , Paracentrotus/metabolismo , Animais , Relação Dose-Resposta a Droga , Larva/efeitos dos fármacos , Larva/metabolismo , Teste de Materiais , Minerais/análise
11.
Environ Toxicol Pharmacol ; 95: 103956, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35963553

RESUMO

Nanoparticles have found use in a wide range of applications, mainly as carriers of active biomolecules. It is thus necessary to assess their toxicity for human health, as well as for the environment, on which there is still a gap of knowledge. In this work, sea urchin Paracentrotus lividus, a widely used model for embryotoxicity and spermiotoxicity, has been used to assess potential detrimental effects of amino-functionalized mesoporous silica nanoparticles (NH2-MSiNPs) on embryonic development. Specifically, gametes quality, embryogenesis morphological and timing alterations, and cellular stress markers, such as mitochondrial functionality, were assessed in presence of different concentrations of NH2-MSiNPs in filtered seawater (FSW). Furthermore, dorsal-ventral axis development and skeletogenesis were characterized by microscopy imaging and gene expression analysis. NH2-MSiNPs determined a strong reduction in the egg fertilization rate. Consequently, the presence of NH2-MSiNPs resulted detrimental in P. lividus embryonic development, with severe morphological alterations correlated with an increased embryos mortality. Finally, NH2-MSiNPs treatment was responsible for other toxic effects, such as reduced mitochondrial function and skeletogenesis alterations, according to the reduced mineralization sites in the endoskeleton formation and the related genes altered expression. Taken together, these results suggest the potential toxic effects of NH2-MSiNPs on the marine ecosystem, with consequences for the development and reproduction of its organisms. Despite their promising potential as carriers of biomolecules, it is pivotal to consider that their uncontrolled use may result harmful to the environment and, consequently, to living organisms.


Assuntos
Nanopartículas , Paracentrotus , Animais , Ecossistema , Embrião não Mamífero , Desenvolvimento Embrionário , Humanos , Nanopartículas/toxicidade , Paracentrotus/genética , Dióxido de Silício/toxicidade
12.
Front Plant Sci ; 13: 936020, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35812940

RESUMO

Durum wheat [Triticum turgidum L. subsp. durum (Desf.) Husn.] can accumulate a high level of Cd in grains with a significant variability depending on cultivars. Understanding how this toxic element is distributed in cereal tissues and grains is essential to improve the nutritional quality of cereal-based products. The main objective of this work was to investigate roots of durum wheat plants (cv. Iride) exposed to different Cd concentrations (0.5 and 5.0 µM) to identify the mechanisms involved in Cd management. Results showed that the root morphology was altered by Cd treatment both at macroscopic (increased number of tips and primary root length) and ultrastructural levels (cell membrane system damaged, cell walls thickened and enriched in suberin). On the other side, Cd was localized in vesicles and in cell walls, and the metal colocalized with the phytosiderophore nicotianamine (NA). Overall, data suggest that Cd is chelated by NA and then compartmentalized, through vesicular trafficking, in the root thickened walls reducing Cd translocation to the aerial organs of the plant.

13.
Nat Nanotechnol ; 17(10): 1111-1119, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36097045

RESUMO

The distinctive properties of single-walled carbon nanotubes (SWCNTs) have inspired the development of many novel applications in the field of cell nanobiotechnology. However, studies thus far have not explored the effect of SWCNT functionalization on transport across the cell walls of prokaryotes. We explore the uptake of SWCNTs in Gram-negative cyanobacteria and demonstrate a passive length-dependent and selective internalization of SWCNTs decorated with positively charged biomolecules. We show that lysozyme-coated SWCNTs spontaneously penetrate the cell walls of a unicellular strain and a multicellular strain. A custom-built spinning-disc confocal microscope was used to image the distinct near-infrared SWCNT fluorescence within the autofluorescent cells, revealing a highly inhomogeneous distribution of SWCNTs. Real-time near-infrared monitoring of cell growth and division reveal that the SWCNTs are inherited by daughter cells. Moreover, these nanobionic living cells retained photosynthetic activity and showed an improved photo-exoelectrogenicity when incorporated into bioelectrochemical devices.


Assuntos
Cianobactérias , Nanotubos de Carbono , Diagnóstico por Imagem , Fluorescência , Muramidase , Nanotubos de Carbono/química
14.
Nanomaterials (Basel) ; 11(1)2020 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-33374979

RESUMO

Nutraceuticals represent complementary or alternative beneficial products to the expensive and high-tech therapeutic tools in modern medicine. Nowadays, their medical or health benefits in preventing or treating different types of diseases is widely accepted, due to fewer side effects than synthetic drugs, improved bioavailability and long half-life. Among herbal and natural compounds, curcumin is a very attractive herbal supplement considering its multipurpose properties. The potential effects of curcumin on glia cells and its therapeutic and protective properties in central nervous system (CNS)-related disorders is relevant. However, curcumin is unstable and easily degraded or metabolized into other forms posing limits to its clinical development. This is particularly important in brain pathologies determined blood brain barrier (BBB) obstacle. To enhance the stability and bioavailability of curcumin, many studies focused on the design and development of curcumin nanodelivery systems (nanoparticles, micelles, dendrimers, and diverse nanocarriers). These nanoconstructs can increase curcumin stability, solubility, in vivo uptake, bioactivity and safety. Recently, several studies have reported on a curcumin exosome-based delivery system, showing great therapeutical potential. The present work aims to review the current available data in improving bioactivity of curcumin in treatment or prevention of neurological disorders.

15.
Microb Cell Fact ; 8: 18, 2009 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-19331655

RESUMO

BACKGROUND: There is evidence from previous works that bacterial secondary metabolism may be stimulated by genetic manipulation of RNA polymerase (RNAP). In this study we have used rifampicin selection as a strategy to genetically improve the erythromycin producer Saccharopolyspora erythraea. RESULTS: Spontaneous rifampicin-resistant (rif) mutants were isolated from the parental strain NRRL2338 and two rif mutations mapping within rpoB, S444F and Q426R, were characterized. With respect to the parental strain, S444F mutants exhibited higher respiratory performance and up to four-fold higher final erythromycin yields; in contrast, Q426R mutants were slow-growing, developmental-defective and severely impaired in erythromycin production. DNA microarray analysis demonstrated that these rif mutations deeply changed the transcriptional profile of S. erythraea. The expression of genes coding for key enzymes of carbon (and energy) and nitrogen central metabolism was dramatically altered in turn affecting the flux of metabolites through erythromycin feeder pathways. In particular, the valine catabolic pathway that supplies propionyl-CoA for biosynthesis of the erythromycin precursor 6-deoxyerythronolide B was strongly up-regulated in the S444F mutants, while the expression of the biosynthetic gene cluster of erythromycin (ery) was not significantly affected. In contrast, the ery cluster was down-regulated (<2-fold) in the Q426R mutants. These strains also exhibited an impressive stimulation of the nitrogen regulon, which may contribute to lower erythromycin yields as erythromycin production was strongly inhibited by ammonium. CONCLUSION: Rifampicin selection is a simple and reliable tool to investigate novel links between primary and secondary metabolism and morphological differentiation in S. erythraea and to improve erythromycin production. At the same time genome-wide analysis of expression profiles using DNA microarrays allowed information to be gained about the mechanisms underlying the stimulatory/inhibitory effects of the rif mutations on erythromycin production.

16.
Environ Microbiol ; 10(10): 2824-41, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18662308

RESUMO

Vetiver is the only grass cultivated worldwide for the root essential oil, which is a mixture of sesquiterpene alcohols and hydrocarbons, used extensively in perfumery and cosmetics. Light and transmission electron microscopy demonstrated the presence of bacteria in the cortical parenchymatous essential oil-producing cells and in the lysigen lacunae in close association with the essential oil. This finding and the evidence that axenic Vetiver produces in vitro only trace amounts of oil with a strikingly different composition compared with the oils from in vivo Vetiver plants stimulated the hypothesis of an involvement of these bacteria in the oil metabolism. We used culture-based and culture-independent approaches to analyse the microbial community of the Vetiver root. Results demonstrate a broad phylogenetic spectrum of bacteria, including alpha-, beta- and gamma-Proteobacteria, high-G+C-content Gram-positive bacteria, and microbes belonging to the Fibrobacteres/Acidobacteria group. We isolated root-associated bacteria and showed that most of them are able to grow by using oil sesquiterpenes as a carbon source and to metabolize them releasing into the medium a large number of compounds typically found in commercial Vetiver oils. Several bacteria were also able to induce gene expression of a Vetiver sesquiterpene synthase. These results support the intriguing hypothesis that bacteria may have a role in essential oil biosynthesis opening the possibility to use them to manoeuvre the Vetiver oil molecular structure.


Assuntos
Bactérias/classificação , Bactérias/metabolismo , Vetiveria/microbiologia , Óleos Voláteis/metabolismo , Bactérias/genética , Bactérias/isolamento & purificação , Carbono/metabolismo , Vetiveria/citologia , Vetiveria/ultraestrutura , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Perfilação da Expressão Gênica , Genes de RNAr , Microscopia , Microscopia Eletrônica , Dados de Sequência Molecular , Filogenia , Proteínas de Plantas/biossíntese , Raízes de Plantas/citologia , Raízes de Plantas/microbiologia , Raízes de Plantas/ultraestrutura , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Homologia de Sequência do Ácido Nucleico , Sesquiterpenos/metabolismo
17.
Eur J Pharm Biopharm ; 127: 432-442, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29605467

RESUMO

PEGylated non-ionic surfactant-based vesicles (NSVs) are promising drug delivery systems for the local, oral and systemic administrations of therapeutics. The aim of this study was to test the cellular biocompatibility and transport of Nile Red-loaded NSVs (NR-NSVs) across the Caco-2-cell monolayers, which represent an in vitro model of human intestinal epithelium. The NR-NSVs assumed a spherical shape with a mean size of 140 nm, and a narrow size distribution. The NR-NSVs did not modify Caco-2 cell viability, which remained unaltered in vitro up to a concentration of 1 mM. The transport studies demonstrated that the NR-NSVs moved across the Caco-2 monolayers without affecting the transepithelial electrical resistance. These results were supported by flow cytometry analysis, which demonstrated that NR-NSVs were internalized inside the Caco-2 cells. Nanoparticle tracking and Transmission Electron Microscopy (TEM) analysis showed the presence of NR-NSVs in the basolateral side of the Caco-2 monolayers. TEM images also showed that NSVs were transported intact across the Caco-2 monolayers, thus demonstrating a predominant transcytosis mechanism of transport through endocytosis. The NSVs did not affect the integrity of the membrane barrier in vitro, and can potentially be used in clinics to increase the oral bioavailability and delivery of therapeutics.


Assuntos
Enterócitos/metabolismo , Absorção Intestinal/fisiologia , Mucosa Intestinal/metabolismo , Polietilenoglicóis/metabolismo , Tensoativos/metabolismo , Disponibilidade Biológica , Transporte Biológico/fisiologia , Células CACO-2 , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Portadores de Fármacos/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Endocitose/fisiologia , Humanos , Nanopartículas/metabolismo
18.
Cell Death Dis ; 9(6): 624, 2018 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-29795378

RESUMO

Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis (TB), has infected over 1.7 billion people worldwide and causes 1.4 million deaths annually. Recently, genome sequence analysis has allowed the reconstruction of Mycobacterium tuberculosis complex (MTBC) evolution, with the identification of seven phylogeographic lineages: four referred to as evolutionarily "ancient", and three "modern". The MTBC strains belonging to "modern" lineages appear to show enhanced virulence that may have warranted improved transmission in humans over ancient lineages through molecular mechanisms that remain to be fully characterized. To evaluate the impact of MTBC genetic diversity on the innate immune response, we analyzed intracellular bacterial replication, inflammatory cytokine levels, and autophagy response in human primary macrophages infected with MTBC clinical isolates belonging to the ancient lineages 1 and 5, and the modern lineage 4. We show that, when compared to ancient lineage 1 and 5, MTBC strains belonging to modern lineage 4 show a higher rate of replication, associated to a significant production of proinflammatory cytokines (IL-1ß, IL-6, and TNF-α) and induction of a functional autophagy process. Interestingly, we found that the increased autophagic flux observed in macrophages infected with modern MTBC is due to an autocrine activity of the proinflammatory cytokine IL-1ß, since autophagosome maturation is blocked by an interleukin-1 receptor antagonist. Unexpectedly, IL-1ß-induced autophagy is not disadvantageous for the survival of modern Mtb strains, which reside within Rab5-positive phagosomal vesicles and avoid autophagosome engulfment. Altogether, these results suggest that autophagy triggered by inflammatory cytokines is compatible with a high rate of intracellular bacilli replication and may therefore contribute to the increased pathogenicity of the modern MTBC lineages.


Assuntos
Autofagia , Interações Hospedeiro-Patógeno/imunologia , Evasão da Resposta Imune , Interleucina-1beta/metabolismo , Macrófagos/imunologia , Mycobacterium tuberculosis/imunologia , Mycobacterium tuberculosis/isolamento & purificação , Filogenia , Autofagossomos/metabolismo , Humanos , Mediadores da Inflamação/metabolismo , Macrófagos/ultraestrutura , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/ultraestrutura , Transdução de Sinais
19.
Adv Food Nutr Res ; 82: 149-204, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28427532

RESUMO

Nanotechnology has paved the way to innovative food packaging materials and analytical methods to provide the consumers with healthier food and to reduce the ecological footprint of the whole food chain. Combining antimicrobial and antifouling properties, thermal and mechanical protection, oxygen and moisture barrier, as well as to verify the actual quality of food, e.g., sensors to detect spoilage, bacterial growth, and to monitor incorrect storage conditions, or anticounterfeiting devices in food packages may extend the products shelf life and ensure higher quality of foods. Also the ecological footprint of food chain can be reduced by developing new completely recyclable and/or biodegradable packages from natural and eco-friendly resources. The contribution of nanotechnologies to these goals is reviewed in this chapter, together with a description of portable devices ("lab-on-chip," sensors, nanobalances, etc.) which can be used to assess the quality of food and an overview of regulations in force on food contact materials.


Assuntos
Embalagem de Alimentos/instrumentação , Alimentos/normas , Nanotecnologia , Técnicas Biossensoriais , Inocuidade dos Alimentos , Humanos , Legislação sobre Alimentos
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