Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 32
Filtrar
1.
Cell Death Discov ; 10(1): 24, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38216593

RESUMO

Modeling human neuronal properties in physiological and pathological conditions is essential to identify novel potential drugs and to explore pathological mechanisms of neurological diseases. For this purpose, we generated a three-dimensional (3D) neuronal culture, by employing the readily available human neuroblastoma SH-SY5Y cell line, and a new differentiation protocol. The entire differentiation process occurred in a matrix and lasted 47 days, with 7 days of pre-differentiation phase and 40 days of differentiation, and allowed the development of a 3D culture in conditions consistent with the physiological environment. Neurons in the culture were electrically active, were able to establish functional networks, and showed features of cholinergic neurons. Hence here we provide an easily accessible, reproducible, and suitable culture method that might empower studies on synaptic function, vesicle trafficking, and metabolism, which sustain neuronal activity and cerebral circuits. Moreover, this novel differentiation protocol could represent a promising cellular tool to study physiological cellular processes, such as migration, differentiation, maturation, and to develop novel therapeutic approaches.

2.
Nanomaterials (Basel) ; 12(13)2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35808140

RESUMO

Heating has recently been applied as an alternative to electrical stimulation to modulate excitability and to induce neuritogenesis and the expression of neuronal markers; however, a long-term functional differentiation has not been described so far. Here, we present the results obtained by a new approach for scalable thermal stimulation on the behavior of a model of dorsal root ganglion neurons, the F-11 cell line. Initially, we performed experiments of bulk stimulation in an incubator for different time intervals and temperatures, and significant differences in neurite elongation and in electrophysiological properties were observed in cultures exposed at 41.5 °C for 30 min. Thus, we exposed the cultures to the same temperature increase using a near-infrared laser to irradiate a disc of Prussian blue nanoparticles and poly-vinyl alcohol that we had adhered to the outer surface of the petri dish. In irradiated cells, neurites were significantly longer, and the electrophysiological properties (action potential firing frequency and spontaneous activity) were significantly increased compared to the control. These results show for the first time that a targeted thermal stimulation could induce morphological and functional neuronal differentiation and support the future application of this method as a strategy to modify neuronal behavior in vivo.

4.
Int J Mol Sci ; 22(6)2021 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-33802689

RESUMO

Palmitoylethanolamide (PEA) is an endogenous lipid produced on demand by neurons and glial cells that displays neuroprotective properties. It is well known that inflammation and neuronal damage are strictly related processes and that microglia play a pivotal role in their regulation. The aim of the present work was to assess whether PEA could exert its neuroprotective and anti-inflammatory effects through the modulation of microglia reactive phenotypes. In N9 microglial cells, the pre-incubation with PEA blunted the increase of M1 pro-inflammatory markers induced by lipopolysaccharide (LPS), concomitantly increasing those M2 anti-inflammatory markers. Images of microglial cells were processed to obtain a set of morphological parameters that highlighted the ability of PEA to inhibit the LPS-induced M1 polarization and suggested that PEA might induce the anti-inflammatory M2a phenotype. Functionally, PEA prevented Ca2+ transients in both N9 cells and primary microglia and antagonized the neuronal hyperexcitability induced by LPS, as revealed by multi-electrode array (MEA) measurements on primary cortical cultures of neurons, microglia, and astrocyte. Finally, the investigation of the molecular pathway indicated that PEA effects are not mediated by toll-like receptor 4 (TLR4); on the contrary, a partial involvement of cannabinoid type 2 receptor (CB2R) was shown by using a selective receptor inverse agonist.


Assuntos
Amidas/farmacologia , Etanolaminas/farmacologia , Microglia/metabolismo , Fármacos Neuroprotetores/farmacologia , Ácidos Palmíticos/farmacologia , Trifosfato de Adenosina/farmacologia , Animais , Cálcio/metabolismo , Polaridade Celular/efeitos dos fármacos , Células Cultivadas , Citocinas/metabolismo , Humanos , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos , Microglia/efeitos dos fármacos , NF-kappa B/metabolismo , Ratos , Receptor CB2 de Canabinoide/metabolismo , Células THP-1 , Acetato de Tetradecanoilforbol/farmacologia , Receptor 4 Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
5.
Molecules ; 25(19)2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32977424

RESUMO

The regeneration of the nervous system is a challenging task. Currently, regenerative medicine approaches that exploit nature-inspired cues are being studied and hold great promise. The possibility to use protein-based matrices functionalized with small oligo- and monosaccharides is of interest since these can be finely tuned to better mimic the native environment. Collagen has been selected as a promising material that has the potential to be further tailored to incorporate carbohydrates in order to drive cell behavior towards neuroregeneration. Indeed, the grafting of carbohydrates to collagen 2D matrices is proved to enhance its biological significance. In the present study, collagen 2D matrices were grafted with different carbohydrate epitopes, and their potential to drive F-11 neuroblastoma cells towards neuronal differentiation was evaluated. Collagen functionalized with α-glucosides was able to differentiate neuroblastoma cells into functional neurons, while sialyl α-(2→6)-galactosides stimulated cell proliferation.


Assuntos
Colágeno/química , Colágeno/farmacologia , Neuroblastoma/patologia , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Glicosilação , Humanos , Neurônios/citologia , Neurônios/efeitos dos fármacos , Medicina Regenerativa
6.
Front Neurol ; 11: 255, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32411069

RESUMO

Sodium channel myotonia is a form of muscle channelopathy due to mutations that affect the Nav1.4 channel. We describe seven families with a series of symptoms ranging from asymptomatic to clearly myotonic signs that have in common two novel mutations, p.Ile215Thr and p.Gly241Val, in the first domain of the Nav1.4 channel. The families described have been clinically and genetically evaluated. p.Ile215Thr and p.Gly241Val lie, respectively, on extracellular and intracellular loops of the first domain of the Nav1.4 channel. We assessed that the p.Ile215Thr mutation can be related to a founder effect in people from Southern Italy. Electrophysiological evaluation of the channel function showed that the voltage dependence of the activation for both the mutant channels was significantly shifted toward hyperpolarized potentials (Ile215Thr: -28.6 ± 1.5 mV and Gly241Val: -30.2 ± 1.3 mV vs. WT: -18.5 ± 1.3 mV). The slow inactivation was also significantly affected, whereas fast inactivation showed a different behavior in the two mutants. We characterized two novel mutations of the SCN4A gene expanding the knowledge about genetics of mild forms of myotonia, and we present, to our knowledge, the first homozygous patient with sodium channel myotonia.

7.
PeerJ ; 7: e7951, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31687277

RESUMO

The isolation and culture of dorsal root ganglion (DRG) neurons cause adaptive changes in the expression and regulation of ion channels, with consequences on neuronal excitability. Considering that not all neurons survive the isolation and that DRG neurons are heterogeneous, it is difficult to find the cellular subtype of interest. For this reason, researchers opt for DRG-derived immortal cell lines to investigate endogenous properties. The F-11 cell line is a hybridoma of embryonic rat DRG neurons fused with the mouse neuroblastoma line N18TG2. In the proliferative condition, F-11 cells do not display a gene expression profile correspondent with specific subclasses of sensory neurons, but the most significant differences when compared with DRGs are the reduction of voltage-gated sodium, potassium and calcium channels, and the small amounts of TRPV1 transcripts. To investigate if functional properties of mature F-11 cells showed more similarities with those of isolated DRG neurons, we differentiated them by serum deprivation. Potassium and sodium currents significantly increased with differentiation, and biophysical properties of tetrodotoxin (TTX)-sensitive currents were similar to those characterized in small DRG neurons. The analysis of the voltage-dependence of calcium currents demonstrated the lack of low threshold activated components. The exclusive expression of high threshold activated Ca2+ currents and of TTX-sensitive Na+ currents correlated with the generation of a regular tonic electrical activity, which was recorded in the majority of the cells (80%) and was closely related to the activity of afferent TTX-sensitive A fibers of the proximal urethra and the bladder. Responses to capsaicin and substance P were also recorded in ~20% and ~80% of cells, respectively. The percentage of cells responsive to acetylcholine was consistent with the percentage referred for rat DRG primary neurons and cell electrical activity was modified by activation of non-NMDA receptors as for embryonic DRG neurons. These properties and the algesic profile (responses to pH5 and sensitivity to both ATP and capsaicin), proposed in literature to define a sub-classification of acutely dissociated rat DRG neurons, suggest that differentiated F-11 cells express receptors and ion channels that are also present in sensory neurons.

8.
Cont Lens Anterior Eye ; 42(5): 487-491, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31519352

RESUMO

PURPOSE: The aim was to develop a method to assess the electrostatic properties of human tear samples, and to evaluate their modifications induced by the wear of contact lenses (CLs). METHOD: The barrier method was developed for the measurement of the isoelectric point (IEP) on relatively small quantities. The method was applied to compare three groups: tears (TNW) of non-wearers, tears (TW_etaf) of regular wearers of etafilcon A CLs, and tears (TW_omaf) of regular wearers of omafilcon A CLs. Zeta potential (ζ) as a function of pH was measured by a Zetasizer Nano ZS90 (Malvern Instruments) on 40%-diluted samples, obtained by mixing 57 µL of tears of different subjects of the same group with 85 µL of HCl aqueous solution. IEP was deduced as the pH at which ζ is zero, i.e. the net electric charge on tear constituents being neutralized. RESULTS: Within an error of about 0.05, IEPs were found to be 2.90 (TNW), 2.80 (TW_omaf), and 3.16 (TW_etaf). On average, a lower H+ concentration is needed to neutralize the surface charge of the tear components of etafilcon A wearers, compared to both TNW and TW_omaf. CONCLUSION: IEP measurements on tear samples of wearers of different types of CLs are proposed in order to enhance the knowledge on the modifications of the profile of charged species in tears. The TW_etaf results, compared to those of the other groups, are compatible with an increase, due to the wear of etafilcon A CLs, of the relative concentration of high-IEP proteins.


Assuntos
Lentes de Contato Hidrofílicas , Metacrilatos , Lágrimas/química , Adolescente , Adulto , Condutividade Elétrica , Humanos , Concentração de Íons de Hidrogênio , Ponto Isoelétrico , Ajuste de Prótese , Lágrimas/fisiologia , Adulto Jovem
9.
Proc Natl Acad Sci U S A ; 116(15): 7483-7492, 2019 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-30923117

RESUMO

Three-dimensional cell cultures are leading the way to the fabrication of tissue-like constructs useful to developmental biology and pharmaceutical screenings. However, their reproducibility and translational potential have been limited by biomaterial and culture media compositions, as well as cellular sources. We developed a construct comprising synthetic multifunctionalized hydrogels, serum-free media, and densely seeded good manufacturing practice protocol-grade human neural stem cells (hNSC). We tracked hNSC proliferation, differentiation, and maturation into GABAergic, glutamatergic, and cholinergic neurons, showing entangled electrically active neural networks. The neuroregenerative potential of the "engineered tissue" was assessed in spinal cord injuries, where hNSC-derived progenitors and predifferentiated hNSC progeny, embedded in multifunctionalized hydrogels, were implanted. All implants decreased astrogliosis and lowered the immune response, but scaffolds with predifferentiated hNSCs showed higher percentages of neuronal markers, better hNSC engraftment, and improved behavioral recovery. Our hNSC-construct enables the formation of 3D functional neuronal networks in vitro, allowing novel strategies for hNSC therapies in vivo.


Assuntos
Diferenciação Celular , Proliferação de Células , Células Imobilizadas , Hidrogéis , Células-Tronco Neurais , Regeneração , Traumatismos da Medula Espinal , Animais , Células Imobilizadas/metabolismo , Células Imobilizadas/patologia , Células Imobilizadas/transplante , Neurônios Colinérgicos/metabolismo , Neurônios Colinérgicos/patologia , Modelos Animais de Doenças , Feminino , Xenoenxertos , Humanos , Hidrogéis/química , Hidrogéis/farmacologia , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/patologia , Células-Tronco Neurais/transplante , Ratos , Ratos Sprague-Dawley , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/patologia , Traumatismos da Medula Espinal/terapia
10.
Cont Lens Anterior Eye ; 42(3): 253-257, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30545776

RESUMO

Lactoferrin (LF), an iron-binding protein with antioxidant activity, is significantly reduced in the lacrimal film of patients affected by keratoconus (KC) compared to healthy subjects, and this is supposed to be the cause for tear iron increase and consequent iron deposition and oxygen free radical accumulation in the cornea. We decided to study if LF-loaded contact lenses (LF-CLs) could exert antioxidant activity on epithelial cells incubated in tears collected from two patients affected by keratoconus (KC1 and KC2). Moreover through this model we indirectly estimated iron concentration in the tears of healthy and KC subjects. Reflex tears were collected during the first 2 min of light or onion-induced lacrimation and stored at -20 °C. After incubation in tears for 18 h, mortality of epithelial cells was investigated by trypan blue exclusion test. Successively, LF-CLs were deposed on cells incubated in KC1 tears. For the indirect determination of iron content, cells were incubated with LF 1.2 mg/mL and different FeSO4 concentrations, and for the estimation of iron from the patient's tears, cells were incubated with free serum medium and healthy tears (1:1) and different FeSO4 concentrations. Epithelial cells incubated with reflex tears of KC patients showed increased mortality (27.7 ± 3.9%, p = 0.0003, for KC1 and 17.6 ± 0.95%, p = 0.014, for KC2) compared to epithelial cells maintained in control healthy tears (8.6 ± 1.2%). This difference in mortality was correlated with tear iron concentration, which was estimated at 4.58 µg/mL for the healthy subjects, at 56.28 µg/mL for KC1, and at 8.7 µg/mL for KC2 patient. Application of LF-CLs counteracted KC tear cytotoxicity restoring viability obtained in the presence of control tears. Therapeutic contact lenses obtained by LF loading can reduce oxidative stress induced by patients' tears and might represent an efficient device to arrest the progression of keratoconus.


Assuntos
Anti-Infecciosos/administração & dosagem , Apoproteínas/administração & dosagem , Lentes de Contato Hidrofílicas , Portadores de Fármacos , Células Epiteliais/efeitos dos fármacos , Ceratocone/metabolismo , Lactoferrina/administração & dosagem , Lágrimas/fisiologia , Adulto , Antioxidantes/administração & dosagem , Células Epiteliais/metabolismo , Feminino , Humanos , Ferro/metabolismo , Rim/citologia , Masculino , Estresse Oxidativo/fisiologia
11.
Front Neurosci ; 11: 500, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28932183

RESUMO

Increasing evidence supports a decisive role for neuroinflammation in the neurodegenerative process of several central nervous system (CNS) disorders. Microglia are essential mediators of neuroinflammation and can regulate a broad spectrum of cellular responses by releasing reactive oxygen intermediates, nitric oxide, proteases, excitatory amino acids, and cytokines. We have recently shown that also in ex-vivo cortical networks of neurons, astrocytes and microglia, an increased level of tumor necrosis factor-alpha (TNF-α) was detected a few hours after exposure to the bacterial endotoxin lipopolysaccharide (LPS). Simultaneously, an atypical "seizure-like" neuronal network activity was recorded by multi-electrode array (MEA) electrophysiology. These effects were prevented by minocycline, an established anti-inflammatory antibiotic. We show here that the same inhibitory effect against LPS-induced neuroinflammation is exerted also by natural plant compounds, polyphenols, such as curcumin (CU, curcuma longa), crocin (CR, saffron), and resveratrol (RE, grape), as well as by the glucagon like peptide-1 receptor (GLP-1R) agonist exendin-4 (EX-4). The drugs tested also caused per-se early transient (variable) changes of network activity. Since it has been reported that LPS-induced neuroinflammation causes rearrangements of glutamate transporters in astrocytes and microglia, we suggest that neural activity could be putatively increased by an imbalance of glial glutamate transporter activity, leading to prolonged synaptic glutamatergic dysregulation.

12.
Clinicoecon Outcomes Res ; 9: 189-199, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28352199

RESUMO

CONTEXT: Children's cough is a daily concern for most pediatricians. The management of both acute and chronic cough requires a systematic and comprehensive approach. Despite the approved protocols for management, the pediatric assessment of cough and the corresponding prescribing attitude frequently do not fit these protocols, which can be affected by parental suggestions - sometimes substantially. OBJECTIVE: The objective of this study was to investigate both the perception and the behavior of a representative sample of Italian pediatricians toward cough in real life. METHODS: A specific questionnaire consisting of 18 questions was prepared. The questionnaire was completed by 300 pediatricians (all members of PAIDOSS: Italian National Observatory on Health of Childhood and Adolescence) who represented ~300,000 children. RESULTS: A vast majority of children have cough throughout the year (99.3% of respondents have cough during autumn/winter and 64.7% in spring/summer). Allergic disease is the most frequent suspected cause of chronic cough in children (53%), and this is supported by the high demand for consultations: 73% seek the opinion of allergologists, 62% of otorhinolaryngologists and only 33% of pulmonologists. The majority of pediatricians (92%) reported that they prescribe therapy in acute cough regardless of cough guidelines. Moreover, the survey pointed out the abuse of aerosol therapy (26% in acute cough and 38% in chronic cough) and of antibiotics prescription (22% in acute cough and 42% in chronic cough). CONCLUSION: Our survey suggests that some Italian pediatricians' therapeutic attitudes should be substantially improved in order to achieve better management of cough in children and to minimize the burden of cough.

13.
Neurotoxicology ; 60: 150-160, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28007400

RESUMO

BACKGROUND: Pyrethroid insecticides are the most popular class of insecticides in the world, despite their near-ubiquity, their effects of delaying the onset of inactivation of voltage-gated sodium (Nav) channels have not been well-evaluated in all the mammalian Nav isoforms. OBJECTIVE: Here we compare the well-studied Nav1.6 isoforms to the less-understood Nav1.1 in their responses to acute deltamethrin exposure. METHODS: We used patch-clamp electrophysiology to record sodium currents encoded by either Nav1.1 or Nav1.6 channels stably expressed in HEK293 cells. Protocols evaluating both resting and use-dependent modification were employed. RESULTS: We found that exposure of both isoforms to 10µM deltamethrin significantly potentiated persistent and tail current densities without affecting peak transient current densities, and only Nav1.1 maintained these significant effects at 1µM deltamethrin. Window currents increased for both as well, and while only Nav1.6 displayed changes in activation slope and V1/2 of steady-state inactivation for peak currents, V1/2 of persistent current activation was hyperpolarized of ∼10mV by deltamethrin in Nav1.1 cells. Evaluating use-dependence, we found that deltamethrin again potentiated persistent and tail current densities in both isoforms, but only Nav1.6 demonstrated use-dependent enhancement, indicating the primary deltamethrin-induced effects on Nav1.1 channels are not use-dependent. CONCLUSION: Collectively, these data provide evidence that Nav1.1 is indeed vulnerable to deltamethrin modification at lower concentrations than Nav1.6, and this effect is primarily mediated during the resting state. GENERAL SIGNIFICANCE: These findings identify Nav1.1 as a novel target of pyrethroid exposure, which has major implications for the etiology of neuropsychiatric disorders associated with loss of Nav1.1-expressing inhibitory neurons.


Assuntos
Inseticidas/farmacologia , Canal de Sódio Disparado por Voltagem NAV1.1/fisiologia , Nitrilas/farmacologia , Piretrinas/farmacologia , Células HEK293 , Humanos , Potenciais da Membrana/efeitos dos fármacos , Canal de Sódio Disparado por Voltagem NAV1.6/fisiologia , Isoformas de Proteínas/fisiologia
14.
Cornea ; 34(6): 693-7, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25961493

RESUMO

PURPOSE: Tear fluid contains antioxidative compounds, vitamin C, glutathione, superoxide dismutase, and lactoferrin (LF), which protect the corneal epithelium from the effects of ultraviolet irradiation, direct airflow, and chemical agents. However, these natural defenses against oxidative stress can decrease, favoring the development of anterior eye disorders, such as keratoconus, dry eye, and Sjögren syndrome. LF is an iron-binding glycoprotein, present in mammalian secretions such as tears and milk, endowed with different physiological functions such as antimicrobial, antiviral, and antioxidant activities. In this work, we studied the capability of different soft contact lenses to adsorb and release LF to restore cellular viability in oxidative stress conditions. METHODS: Three types of contact lenses (filcon V, galyfilcon A, and filcon IB) were loaded with LF and then incubated with TsA or human corneal epithelial primary cells. After oxidative stress induction with 250 µM or 125 µM H2O2, cell viability was evaluated. RESULTS: Data showed that the highest quantity of LF loaded in contact lenses was between 61 µg (for filcon V) and 39 µg (for filcon IB); the release was between 49% and 100% of protein adsorbed. LF released from contact lenses maintained its antioxidant activity at least for 24 hours and was able to protect human epithelial cells from the detrimental effects of oxidative stress. CONCLUSIONS: These results demonstrate that LF-loaded contact lenses could represent a new therapeutic approach to treat ocular surface pathologies characterized by high levels of oxidative stress.


Assuntos
Anti-Infecciosos/administração & dosagem , Apoproteínas/administração & dosagem , Lentes de Contato Hidrofílicas , Doenças da Córnea/prevenção & controle , Sistemas de Liberação de Medicamentos , Epitélio Corneano/efeitos dos fármacos , Lactoferrina/administração & dosagem , Estresse Oxidativo/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular , Epitélio Corneano/citologia , Humanos , Peróxido de Hidrogênio/toxicidade , Oxidantes/toxicidade
15.
Front Cell Neurosci ; 8: 361, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25404893

RESUMO

We show here that a mild sterile inflammation induced by the endotoxin lipopolysaccharide (LPS), in a neuron/astrocyte/microglial cortical network, modulates neuronal excitability and can initiate long-duration burst events resembling epileptiform seizures, a recognized feature of various central nervous neurodegenerative, neurological and acute systemic diseases associated with neuroinflammation. To study this action, we simultaneously analyzed the reverberating bursting activity of a hundred neurons by using in vitro multi-electrode array methods. ∼5 h after LPS application, we observed a net increase in the average number of spikes elicited in engaged cells and within each burst, but no changes neither in spike waveforms nor in burst rate. This effect was characterized by a slow, twofold exponential increase of the burst duration and the appearance of rarely occurring long burst events that were never seen during control recordings. These changes and the time-course of microglia-released proinflammatory cytokine, tumor necrosis factor-alpha (TNF-α), were blocked by pre-treatment with 50 nM minocycline, an established anti-inflammatory agent which was inactive when applied alone. Assay experiments also revealed that application of 60 pM exogenous TNF-α after 12-15 h, produced non-washable changes of neuronal excitability, completely different from those induced by LPS, suggesting that TNF-α release alone was not responsible for our observed findings. Our results indicate that the link between neuroinflammation and hyperexcitability can be unveiled by studying the long-term activity of in vitro neuronal/astrocyte/microglial networks.

16.
ACS Appl Mater Interfaces ; 6(22): 19606-12, 2014 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-25356999

RESUMO

Drug-loaded contact lenses are emerging as the preferred treatment method for several ocular diseases, and efforts are being directed to promote extended and controlled delivery. One strategy is based on delivery induced by environmental triggers. One of these triggers can be hydrogen peroxide, since many platforms based on drug-loaded nanoparticles were demonstrated to be hydrogen-peroxide responsive. This is particularly interesting when hydrogen peroxide is the result of a specific pathophysiological condition. Otherwise, an alternative route to induce drug delivery is here proposed, namely the mechano-synthesis. The present work represents the proof-of-concept of the mechanosynthesis of hydrogen peroxide in siloxane-hydrogel contact lenses as a consequence of the cleavage of siloxane bonds at the interface between the polymer and water in aqueous phase. Their spongy morphology makes contact lenses promising systems for mechanical-to-chemical energy conversion, since the amount of hydrogen peroxide is expected to scale with the interfacial area between the polymer and water. The eyelid pressure during wear is sufficient to induce the hydrogen peroxide synthesis with concentrations which are biocompatible and suitable to trigger the drug release through hydrogen-peroxide-responsive platforms. For possible delivery on demand, the integration of piezoelectric polymers in the siloxane-hydrogel contact lenses could be designed, whose mechanical deformation could be induced by an applied wireless-controlled voltage.


Assuntos
Lentes de Contato , Sistemas de Liberação de Medicamentos , Oftalmopatias/tratamento farmacológico , Humanos , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Peróxido de Hidrogênio/química , Siloxanas/química
17.
Expert Opin Drug Metab Toxicol ; 10(10): 1381-95, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25219631

RESUMO

INTRODUCTION: For more than a century, aspirin has been used for the acute treatment of primary headaches. However, the many formulations available are characterized by differences in the pharmacokinetic profile that could affect therapy effectiveness. AREAS COVERED: The formulations of aspirin affect the speed of absorption of the drug. This feature, in turn, moduates the peak plasmatic concentration (the faster the absorption, the higher the peak plasmatic concentration of aspirin). Recently, a new formulation, consisting in a micronized tablet with an effervescent nucleus, has been shown to be comparable to the formulations associated to the faster absorption. The efficacy of aspirin in migraine is well characterized: the drug is able to rapidly reduce pain and restore functionality, acting also on associated symptoms, in a manner comparable to that of oral sumatriptan. In tension-type headache, aspirin acts in a dose-dependent fashion. The safety profile of the drug is favorable: gastrointestinal complaints are generally mild in intensity and with an incidence comparable to that of ibuprofen and paracetamol. EXPERT OPINION: According to international guidelines, aspirin should be considered as first-line therapy in primary headaches. Formulations that allow fast absorption, like the new micronized tablets, and portability, are to be preferred.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Aspirina/uso terapêutico , Cefaleia/tratamento farmacológico , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/farmacocinética , Aspirina/administração & dosagem , Aspirina/farmacocinética , Relação Dose-Resposta a Droga , Humanos , Transtornos de Enxaqueca/tratamento farmacológico , Guias de Prática Clínica como Assunto , Sumatriptana/administração & dosagem , Sumatriptana/uso terapêutico , Comprimidos
18.
Pulm Pharmacol Ther ; 29(2): 224-32, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25111667

RESUMO

Post-viral cough is a type of cough originating from upper respiratory tract infections that persists after the infection is resolved. Although it was hypothesized that bronchodilators might have a role in the management of post-viral cough, a clear demonstration of their efficacy is missing. Therefore, we tested the efficacy of a combination of a ß-agonist and an anticholinergic agent in reducing post-viral cough with a randomized, double blind, placebo controlled clinical trial. Patients were treated for 10 days with either a nebulized combination of salbutamol 1.875 mg/0.5 mL and ipratropium bromide 0.375 mg/0.5 mL, or a placebo, and followed up for another 10 days. Daytime and nighttime cough severity and spirometry testing were assessed before starting treatment, after 10 and 20 days. Ninety-two patients were randomized to receive placebo (n = 46) or the active treatment (n = 46); nine of them (4 in the placebo group, 5 in the active treatment group) dropped out from the study. Daytime and nighttime cough severity were significantly reduced in both groups during the study period, but the reduction was more prominent in the active treatment group vs. placebo after 10 days of treatment (P = 0.003 for day cough; P = 0.061 for night cough), whereas at the end of follow-up period cough severity was comparable between the two groups. Small but significant increases in spirometric parameters were observed in the active treatment vs. placebo group, although at the end of follow-up these values returned to be comparable to placebo. The frequency of adverse events was not significantly different between the two groups of patients. We concluded that a combination of a ß-agonist and an anticholinergic agent can effectively reduce post-viral cough, and can thus represent a valid option for this type of cough.


Assuntos
Albuterol/uso terapêutico , Broncodilatadores/uso terapêutico , Tosse/tratamento farmacológico , Ipratrópio/uso terapêutico , Administração por Inalação , Adulto , Idoso , Albuterol/administração & dosagem , Broncodilatadores/administração & dosagem , Tosse/etiologia , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Ipratrópio/administração & dosagem , Masculino , Pessoa de Meia-Idade , Infecções Respiratórias/complicações , Infecções Respiratórias/virologia , Espirometria , Adulto Jovem
19.
Artigo em Inglês | MEDLINE | ID: mdl-25104926

RESUMO

Autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE) is a partial sleep-related epilepsy which can be caused by mutant neuronal nicotinic acetylcholine receptors (nAChR). We applied multi-electrode array (MEA) recording methods to study the spontaneous firing activity of neocortical cultures obtained from mice expressing or not (WT) an ADNFLE-linked nAChR subunit (ß2-V287L). More than 100,000 up-states were recorded during experiments sampling from several thousand neurons. Data were analyzed by using a fast sliding-window procedure which computes histograms of the up-state durations. Differently from the WT, cultures expressing ß2-V287L displayed long (10-32 s) synaptic-induced up-state firing events. The occurrence of such long up-states was prevented by both negative (gabazine, penicillin G) and positive (benzodiazepines) modulators of GABAA receptors. Carbamazepine (CBZ), a drug of choice in ADNFLE patients, also inhibited the long up-states at micromolar concentrations. In cultures expressing ß2-V287L, no significant effect was observed on the action potential waveform either in the absence or in the presence of pharmacological treatment. Our results show that some aspects of the spontaneous hyperexcitability displayed by a murine model of a human channelopathy can be reproduced in neuronal cultures. In particular, our cultures represent an in vitro chronic model of spontaneous epileptiform activity, i.e., not requiring pre-treatment with convulsants. This opens the way to the study in vitro of the role of ß2-V287L on synaptic formation. Moreover, our neocortical cultures on MEA platforms allow to determine the effects of prolonged pharmacological treatment on spontaneous network hyperexcitability (which is impossible in the short-living brain slices). Methods such as the one we illustrate in the present paper should also considerably facilitate the preliminary screening of antiepileptic drugs (AEDs), thereby reducing the number of in vivo experiments.


Assuntos
Rede Nervosa/fisiologia , Neurônios/fisiologia , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/genética , Análise de Variância , Animais , Anticonvulsivantes/farmacologia , Benzodiazepinas/farmacologia , Carbamazepina/farmacologia , Células Cultivadas , Modelos Animais de Doenças , Epilepsia do Lobo Frontal/genética , Epilepsia do Lobo Frontal/patologia , Leucina/genética , Camundongos , Camundongos Transgênicos , Mutação/genética , Rede Nervosa/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Receptores Nicotínicos/genética , Transfecção , Valina/genética
20.
ACS Chem Neurosci ; 5(4): 261-5, 2014 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-24625037

RESUMO

Despite the relevance of carbohydrates as cues in eliciting specific biological responses, glycans have been rarely exploited in the study of neuronal physiology. We report thereby the study of the effect of neoglucosylated collagen matrices on neuroblastoma F11 cell line behavior. Morphological and functional analysis clearly showed that neoglucosylated collagen matrices were able to drive cells to differentiate. These data show for the first time that F11 cells can be driven from proliferation to differentiation without the use of chemical differentiating agents. Our work may offer to cell biologists new opportunities to study neuronal cell differentiation mechanisms in a cell environment closer to physiological conditions.


Assuntos
Colágeno/farmacocinética , Matriz Extracelular/metabolismo , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Neurônios/metabolismo , Neurônios/patologia , Engenharia Tecidual/métodos , Animais , Diferenciação Celular , Linhagem Celular , Proliferação de Células , Colágeno/química , Camundongos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA