Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 17 de 17
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
Antioxidants (Basel) ; 12(3)2023 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-36978998

RESUMEN

Astaxanthin, a natural compound of Haematococcus pluvialis, possesses antioxidant, anti-inflammatory, anti-tumor and immunomodulatory activities. It also represents a potential therapeutic in Alzheimer's disease (AD), that is related to oxidative stress and agglomeration of proteins such as amyloid-beta (Aß). Aß is a neurotoxic protein and a substrate of tissue transglutaminase (TG2), an ubiquitary protein involved in AD. Herein, the effect of astaxanthin pretreatment on olfactory ensheathing cells (OECs) exposed to Aß(1-42) or by Aß(25-35) or Aß(35-25), and on TG2 expression were assessed. Vimentin, GFAP, nestin, cyclin D1 and caspase-3 were evaluated. ROS levels and the percentage of cell viability were also detected. In parallel, delayed luminescence (DL) was used to monitor mitochondrial status. ASTA reduced TG2, GFAP and vimentin overexpression, inhibiting cyclin D1 levels and apoptotic pathway activation which induced an increase in the nestin levels. In addition, significant changes in DL intensities were particularly observed in OECs exposed to Aß toxic fragment (25-35), that completely disappear when OECs were pre-incubated in astaxantin. Therefore, we suggest that ASTA pre-treatment might represent an innovative mechanism to contrast TG2 overexpression in AD.

2.
Int J Mol Sci ; 22(7)2021 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-33806203

RESUMEN

Herein, we assessed the effect of full native peptide of amyloid-beta (Aß) (1-42) and its fragments (25-35 and 35-25) on tissue transglutaminase (TG2) and its isoforms (TG2-Long and TG2-Short) expression levels on olfactory ensheathing cells (OECs). Vimentin and glial fibrillary acid protein (GFAP) were also studied. The effect of the pre-treatment with indicaxanthin from Opuntia ficus-indica fruit on TG2 expression levels and its isoforms, cell viability, total reactive oxygen species (ROS), superoxide anion (O2-), and apoptotic pathway activation was assessed. The levels of Nestin and cyclin D1 were also evaluated. Our findings highlight that OECs exposure to Aß(1-42) and its fragments induced an increase in TG2 expression levels and a different expression pattern of its isoforms. Indicaxanthin pre-treatment reduced TG2 overexpression, modulating the expression of TG2 isoforms. It reduced total ROS and O2- production, GFAP and Vimentin levels, inhibiting apoptotic pathway activation. It also induced an increase in the Nestin and cyclin D1 expression levels. Our data demonstrated that indicaxanthin pre-treatment stimulated OECs self-renewal through the reparative activity played by TG2. They also suggest that Aß might modify TG2 conformation in OECs and that indicaxanthin pre-treatment might modulate TG2 conformation, stimulating neural regeneration in Alzheimer's disease.


Asunto(s)
Péptidos beta-Amiloides/metabolismo , Betaxantinas/farmacología , Proteínas de Unión al GTP/metabolismo , Regulación Enzimológica de la Expresión Génica , Bulbo Olfatorio/metabolismo , Piridinas/farmacología , Transglutaminasas/metabolismo , Enfermedad de Alzheimer/metabolismo , Animales , Apoptosis , Diferenciación Celular , Ciclina D1/metabolismo , Proteína Ácida Fibrilar de la Glía/metabolismo , Humanos , Ratones , Regeneración Nerviosa , Nestina/metabolismo , Opuntia/química , Estrés Oxidativo , Proteína Glutamina Gamma Glutamiltransferasa 2 , Isoformas de Proteínas , Especies Reactivas de Oxígeno/metabolismo , Vimentina/metabolismo
3.
Am J Case Rep ; 21: e921517, 2020 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-32255770

RESUMEN

BACKGROUND Nontuberculous mycobacteria (NTM) are environmental pathogens that cause an increasing number of diseases, in particular in immunosuppressed patients. Diagnosing NTM infections may be difficult because clinical presentation is unspecific and resembles other conditions such as tuberculosis, lymphomas, or septicemia. CASE REPORT We report the case of a 62-year-old male with a recent history of autologous bone marrow transplantation for a follicular lymphoma admitted to our department for long-lasting remittent fever and abscess-like splenic nodules. The patient was diagnosed with mixed systemic infection by Mycobacterium abscessus and Mycobacterium celatum localized in spleen, bone marrow and kidneys. CONCLUSIONS In this case a rare disseminated atypical mycobacteriosis was diagnosed and treated. As far as we know this is the first case in the literature of M. abscessus localization either in the spleen or in the bone marrow. Our patient underwent a complex long-term therapy and had a complete resolution of the disease.


Asunto(s)
Antibacterianos/uso terapéutico , Huésped Inmunocomprometido , Infecciones por Mycobacterium no Tuberculosas/tratamiento farmacológico , Mycobacterium abscessus/efectos de los fármacos , Mycobacterium/efectos de los fármacos , Trasplante de Médula Ósea , Humanos , Linfoma Folicular/inmunología , Masculino , Persona de Mediana Edad
4.
Sci Rep ; 10(1): 4680, 2020 03 13.
Artículo en Inglés | MEDLINE | ID: mdl-32170186

RESUMEN

Herein, we assessed the effect of Ferulic Acid (FA), a natural antioxidant with anti-cancer effect, on the human glioblastoma cells through molecular and Delayed Luminescence (DL) studies. DL, a phenomenon of ultra-week emission of optical photons, was used to monitor mitochondrial assessment. The effect of FA loaded in nanostructured lipid carriers (NLCs) was also assessed. To validate NLCs as a drug delivery system for glioblastoma treatment, particular attention was focused on their effect. We found that free FA induced a significant decrease in c-Myc and Bcl-2 expression levels accompanied by the apoptotic pathway activation. Blank NLCs, even if they did not induce cytotoxicity and caspase-3 cleavage, decreased Bcl-2, ERK1/2, c-Myc expression levels activating PARP-1 cleavage. The changes in DL intensity and kinetics highlighted a possible effect of nanoparticle matrix on mitochondria, through the involvement of the NADH pool and ROS production that, in turn, activates ERK1/2 pathways. All the effects on protein expression levels and on the activation of apoptotic pathway appeared more evident when the cells were exposed to FA loaded in NLCs. We demonstrated that the observed effects are due to a synergic pro-apoptotic influence exerted by FA, whose bio-availability increases in the glioblastoma cells, and NLCs formulation.


Asunto(s)
Apoptosis/efectos de los fármacos , Ácidos Cumáricos/administración & dosificación , Portadores de Fármacos , Lípidos , Mediciones Luminiscentes , Apoptosis/genética , Línea Celular Tumoral , Ácidos Grasos/metabolismo , Expresión Génica , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/patología , Humanos , Proteína Quinasa 1 Activada por Mitógenos/genética , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/genética , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Transducción de Señal
5.
J Exp Biol ; 223(Pt 5)2020 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-32041804

RESUMEN

Several evidences have suggested the ability of radiofrequency electromagnetic fields to influence biological systems, even if the action mechanisms are not well understood. There are few data on the effect of radiofrequency electromagnetic fields on self-renewal of neural progenitor cells. A particular glial type that shows characteristics of stem cells is olfactory ensheathing cells (OECs). Herein, we assessed the non-thermal effects induced on OECs through radiofrequency electromagnetic fields changing the envelope of the electromagnetic wave. Primary OEC cultures were exposed to continuous or amplitude-modulated 900 MHz electromagnetic fields, in the far-field condition and at different exposure times (10, 15, 20 min). The expression of OEC markers (S-100 and nestin), cytoskeletal proteins (GFAP and vimentin), apoptotic pathway activation by caspase-3 cleavage and cell viability were evaluated. Our results highlight that 20 min of exposure to continuous or amplitude-modulated 900 MHz electromagnetic fields induced a different and significant decrease in cell viability. In addition, according to the electromagnetic field waveform, diverse dynamic changes in the expression of the analysed markers in OECs and activation of the apoptotic pathway were observed. The data suggest that radiofrequency electromagnetic fields might play different and important roles in the self-renewal of OEC stem cells, which are involved in nervous system repair.


Asunto(s)
Proteínas del Citoesqueleto/metabolismo , Ratones/fisiología , Bulbo Olfatorio/metabolismo , Ondas de Radio/efectos adversos , Animales , Animales Recién Nacidos , Células Cultivadas , Bulbo Olfatorio/efectos de la radiación
6.
J Photochem Photobiol B ; 198: 111589, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31437761

RESUMEN

Glucose is a natural chemical compound and is one of the most abundant organic molecules in nature. Plants and algae are able to produce it from water and carbon dioxide during photosynthesis, using energy of photons coming from the sun. It is very important in life processes because, in energy metabolism, Glucose is the most important source of energy in all organisms. As energy reservoir it is partially stored as a polymer, in plants mainly as starch and amylopectin and in animals as glycogen. Moreover it is used as cellulose, the most abundant carbohydrate, to strengthen plants and algae cell walls. In this paper we study the Delayed Luminescence from Glucose and its polymers, Amylose and Cellulose, composed by chains of glucose connected by different bond, as well as Glucose water solution, in order to acquire new knowledge on the mechanisms responsible for this phenomenon and check the possibility to give in-depth analysis of possible collective states present in Glucose-based structures. The phenomenon of DL in biological systems is not a byproduct, as one can naively expect. Instead, it is a property and necessity of the condensed matter, which can be also used as a tool to study the latter. It is a manifestation of the physical and biochemical processes in the system, on one hand side, and, on the other hand side, of its structural properties, in particular, of the presence and type of crystal-like structure, resulting in specific energy spectrum and electron transitions, as will be presented below. We show that the quantum yield and time trends of the Delayed Luminescence depend on the structure of systems under study. Significant differences in Delayed Luminescence parameters from cellulose before and after imbibition have been observed, indicating that Delayed Luminescence could be used to discriminate between various structures and follow the formation or demolition of them. The experimental results qualitatively agree with the soliton mechanism of the Delayed luminescence.


Asunto(s)
Glucanos/química , Espectrometría de Fluorescencia , Amilosa/química , Animales , Celulosa/química , Cinética , Ratones
7.
J Photochem Photobiol B ; 187: 126-130, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30145462

RESUMEN

The evaluation of optical properties of biological samples is gaining increasing interests both in scientific and commercial fields concerning agriculture and food processing. The optical techniques can indeed be able to provide information on quality assessment in a fast and non-destructive way. This feature makes them suitable for automatic management of control processes. In this paper, we propose to use the Delayed Luminescence, a ultra-weak and photo-induced emission of optical photons, as a tool for a rapid evaluation of germination performance, the principal index reflecting seed quality. Two lots of 'Mirella' F1 watermelon dried seeds, of 96 seeds each, were considered. The seeds were analyzed in the conditions as provided by seed/breeding company. Characteristics of Delayed Luminescence emission from each single seed were correlated to the different germination levels as assessed by International Seed Testing Procedures. Parametric differences in the two lots were determined, based on the relaxation kinetics of some spectral components. A control test, with the aim to construct a calibration model, was conceived and successfully tested. Time decays of Delayed Luminescence spectral components at central wavelengths 450 nm, 550 nm and 650 nm, corresponding to spectrum region where natural biomarkers as NADH, flavins and lipopigments, protoporphyrin and ROS respectively emit, have been evaluated. The results show that such time decays are strictly connected to the biological state of the system under analysis and allow also proposing Delayed Luminescence measurement as a quick, cheap and non-destructive test for seed viability analysis.


Asunto(s)
Citrullus/química , Mediciones Luminiscentes , Citrullus/crecimiento & desarrollo , Flavinas/química , Flavinas/metabolismo , Germinación/fisiología , Lípidos/química , NAD/química , NAD/metabolismo , Protoporfirinas/química , Protoporfirinas/metabolismo , Especies Reactivas de Oxígeno/química , Especies Reactivas de Oxígeno/metabolismo , Semillas/química , Semillas/crecimiento & desarrollo
8.
PLoS One ; 13(1): e0191861, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29377914

RESUMEN

The crucial role of water in the engine of life have encouraged many researchers in studying, both theoretically and experimentally, the possible "structure" of water. Many properties of water have been related to the interplay between two distinct and interconverting structural species, namely the low-density water (LDW) and the high-density water (HDW). Supported by the results obtained with other aqueous solutions, this paper deals with the possibility of using the ultra-weak delayed luminescence (DL) to investigate water structuring in a mixture with glycerol, characterized only by hydrogen bonds between the various molecules. Spectral and temporal characteristics of DL decays give information on the two components of the mixture, by evidencing the contribution of water at glycerol concentrations close to the values used in cryopreservation. DL results have shown a correlation with LDW clusters size as determined by other researchers on the basis of neutron diffraction experiments and computational modelling, as reported in Literature.


Asunto(s)
Glicerol/química , Agua/química , Luminiscencia , Soluciones , Análisis Espectral
9.
PLoS One ; 11(12): e0167998, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27936220

RESUMEN

The optical technique based on the measurement of delayed luminescence emitted from the biological samples has demonstrated its ability to provide valid and predictive information on the functional status of various biological systems. We want to extend this technique to study the effect of ionizing radiation on biological systems. In particular we are interested in the action of ion beams, used for therapeutic purposes or to increase the biological diversity. In general, the assessment of the damage that radiation produces both in the target objects and in the surrounding tissues, requires considerable time because is based on biochemical analysis or on the examination of the evolution of the irradiated systems. The delayed luminescence technique could help to simplify this investigation. We have so started our studies performing irradiations of some relatively simple vegetable models. In this paper we report results obtained from mung bean (Vigna radiata) seeds submitted to a 12C ion beam at the energy of 62 MeV/nucleon. The dry seeds were irradiated at doses from 50 to 7000 Gy. The photoinduced delayed luminescence of each seed before and after ion irradiation was measured. The growth of seedlings after irradiation was compared with that of untreated seeds. A growth reduction on increasing the dose was registered. The results show strong correlations between the ion irradiation dose, seeds growth and delayed luminescence intensity. In particular, the delayed luminescence intensity is correlated by a logistic function to the seedlings elongation and, after performing a suitable measurement campaign based on blind tests, it could become a tool able to predict the growth of seeds after ion irradiation. Moreover these results demonstrate that measurements of delayed luminescence could be used as a fast and non-invasive technique to check the effects of ion beams on relatively simple biological systems.


Asunto(s)
Luminiscencia , Desarrollo de la Planta , Radiación Ionizante , Relación Dosis-Respuesta en la Radiación , Germinación/efectos de la radiación , Semillas/efectos de la radiación
10.
J Biomed Opt ; 19(11): 117005, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25393968

RESUMEN

Correlation between apoptosis and UVA-induced ultraweak photon emission delayed luminescence (DL) from tumor thyroid cell lines was investigated. In particular, the effects of berberine, an alkaloid that has been reported to have anticancer activities, on two cancer cell lines were studied. The FTC-133 and 8305C cell lines, as representative of follicular and anaplastic thyroid human cancer, respectively, were chosen. The results show that berberine is able to arrest cell cycle and activate apoptotic pathway as shown in both cell lines by deoxyribonucleic acid fragmentation, caspase-3 cleavage, p53 and p27 protein overexpression. In parallel, changes in DL spectral components after berberine treatment support the hypothesis that DL from human cells originates mainly from mitochondria, since berberine acts especially at the mitochondrial level. The decrease of DL blue component for both cell lines could be related to the decrease of intra-mitochondrial nicotinamide adenine dinucleotide and may be a hallmark of induced apoptosis. In contrast, the response in the red spectral range is different for the two cell lines and may be ascribed to a different iron homeostasis.


Asunto(s)
Apoptosis/efectos de los fármacos , Berberina/farmacología , Mediciones Luminiscentes/métodos , Neoplasias de la Tiroides/química , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/análisis , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/metabolismo , Humanos , Transducción de Señal/efectos de los fármacos , Análisis Espectral , Glándula Tiroides/citología , Proteína p53 Supresora de Tumor/análisis , Proteína p53 Supresora de Tumor/metabolismo
11.
J Photochem Photobiol B ; 139: 76-84, 2014 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-24912405

RESUMEN

The study of the photoinduced ultraweak photon emission in the optical wavelength range, namely the Delayed Luminescence, from human cells and tissues has an increasingly growing interest in view of its possible application in optical biopsy. Due to the low level, dedicated experimental set-up are necessary to reveal such photoluminescence signal. The paper reviews the results obtained in the field of cancer research, by using the experimental equipment for fast ultraweak luminescence analysis ARETUSA developed at the National Southern Laboratories of the National Nuclear Physics Institute (LNS-INFN), in Catania, Italy. Delayed Luminescence signals from normal and cancer cells are compared and the relationship between Delayed Luminescence and apoptosis is investigated.


Asunto(s)
Mediciones Luminiscentes/instrumentación , Neoplasias/patología , Apoptosis , Humanos , Modelos Biológicos
12.
J Biomed Opt ; 18(12): 127006, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24365956

RESUMEN

The role of mitochondrial complex I in ultraweak photon-induced delayed photon emission [delayed luminescence (DL)] of human leukemia Jurkat T cells was probed by using complex I targeting agents like rotenone, menadione, and quercetin. Rotenone, a complex I-specific inhibitor, dose-dependently increased the mitochondrial level of reduced nicotinamide adenine dinucleotide (NADH), decreased clonogenic survival, and induced apoptosis. A strong correlation was found between the mitochondrial levels of NADH and oxidized flavin mononucleotide (FMNox) in rotenone-, menadione- and quercetin-treated cells. Rotenone enhanced DL dose-dependently, whereas quercetin and menadione inhibited DL as well as NADH or FMNox. Collectively, the data suggest that DL of Jurkat cells originates mainly from mitochondrial complex I, which functions predominantly as a dimer and less frequently as a tetramer. In individual monomers, both pairs of pyridine nucleotide (NADH/reduced nicotinamide adenine dinucleotide phosphate) sites and flavin (FMN-a/FMN-b) sites appear to bind cooperatively their specific ligands. Enhancement of delayed red-light emission by rotenone suggests that the mean time for one-electron reduction of ubiquinone or FMN-a by the terminal Fe/S center (N2) is 20 or 284 µs, respectively. All these findings suggest that DL spectroscopy could be used as a reliable, sensitive, and robust technique to probe electron flow within complex I in situ.


Asunto(s)
Complejo I de Transporte de Electrón , Espectrometría de Fluorescencia/métodos , Apoptosis/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Complejo I de Transporte de Electrón/química , Complejo I de Transporte de Electrón/efectos de los fármacos , Complejo I de Transporte de Electrón/metabolismo , Colorantes Fluorescentes/química , Colorantes Fluorescentes/metabolismo , Humanos , Peróxido de Hidrógeno/farmacología , Células Jurkat , Cinética , NAD/química , NAD/metabolismo , NADP/química , NADP/metabolismo , Rotenona/farmacología , Desacopladores/farmacología
13.
Oxid Med Cell Longev ; 2012: 498914, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22829956

RESUMEN

Following previous work, we investigated in more detail the relationship between apoptosis and delayed luminescence (DL) in human leukemia Jurkat T cells under a wide variety of treatments. We used menadione and hydrogen peroxide to induce oxidative stress and two flavonoids, quercetin, and epigallocatechin gallate, applied alone or in combination with menadione or H(2)O(2). 62 MeV proton beams were used to irradiate cells under a uniform dose of 2 or 10 Gy, respectively. We assessed apoptosis, cell cycle distributions, and DL. Menadione, H(2)O(2) and quercetin were potent inducers of apoptosis and DL inhibitors. Quercetin decreased clonogenic survival and the NAD(P)H level in a dose-dependent manner. Proton irradiation with 2 Gy but not 10 Gy increased the apoptotic rate. However, both doses induced a substantial G(2)/M arrest. Quercetin reduced apoptosis and prolonged the G(2)/M arrest induced by radiation. DL spectroscopy indicated that proton irradiation disrupted the electron flow within Complex I of the mitochondrial respiratory chain, thus explaining the massive necrosis induced by 10 Gy of protons and also suggested an equivalent action of menadione and quercetin at the level of the Fe/S center N2, which may be mediated by their binding to a common site within Complex I, probably the rotenone-binding site.


Asunto(s)
Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , Flavonoides/farmacología , Leucemia/patología , Luminiscencia , Oxidantes/toxicidad , Protones , Catequina/análogos & derivados , Catequina/farmacología , Ciclo Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Clonales , Humanos , Peróxido de Hidrógeno/toxicidad , Células Jurkat , Cinética , NADP/metabolismo , Teoría Cuántica , Quercetina/farmacología , Factores de Tiempo , Vitamina K 3/toxicidad
14.
J Biol Phys ; 38(1): 181-95, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23277678

RESUMEN

Fully understanding the structure of water is a crucial point in biophysics because this liquid is essential in the operation of the engines of life. Many of its amazing anomalies seem to be tailored to support biological processes and, during about a century, several models have been developed to describe the water structuring. In particular, a theory assumes that water is a mixture of domains constituted by two distinct and inter-converting structural species, the low-density water (LDW) and the high-density water (HDW). According to this theory, by using some particular solutes or changing the water temperature, it should be possible to modify the equilibrium between the two species, changing in this way the water behavior in specific biological processes, as in governing the shape and stability of the structures of proteins. In this work, we assess the possibility of obtaining information on the structures induced in water by specific salts or by temperature by measuring the delayed luminescence (DL) of some salt solutions and of water in the super-cooled regime. Previous works have demonstrated that the delayed luminescence of a system is correlated with its dynamic ordered structures. The results show significant DL signals only when the formation of LDW domains is expected. The measurement reveals a similar activation energy for the domains both in aqueous salt solutions and super-cooled water. It is worth noting that the time trend of DL signals suggests the existence of structures unusually long-lasting in time, up to the microsecond range.

15.
Cell Biochem Biophys ; 58(3): 169-79, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20697976

RESUMEN

Menadione (MD) is an effective cytotoxic drug able to produce intracellularly large amounts of superoxide anion. Quercetin (QC), a widely distributed bioflavonoid, can exert both antioxidant and pro-oxidant effects and is known to specifically inhibit cell proliferation and induce apoptosis in different cancer cell types. We have investigated the relation between delayed luminescence (DL) induced by UV-laser excitation and the effects of MD, hydrogen peroxide, and QC on apoptosis and cell cycle in human leukemia Jurkat T-cells. Treatments with 500 µM H2O2 and 250 µM MD for 20 min produced 66.0 ± 4.9 and 46.4 ± 8.6% apoptotic cell fractions, respectively. Long-term (24 h) pre-exposure to 5 µM, but not 0.5 µM QC enhanced apoptosis induced by MD, whereas short-term (1 h) pre-incubation with 10 µM QC offered 50% protection against H2O2-induced apoptosis, but potentiated apoptosis induced by MD. Since physiological levels of QC in the blood are normally less than 10 µM, these data can provide relevant information regarding the benefits of flavonoid-combined treatments of leukemia. All the three drugs exerted significant effects on DL. Our data are consistent with (1) the involvement of Complex I of the mitochondrial respiratory chain as an important source of delayed light emission on the 10 µs-10 ms scale, (2) the ability of superoxide anions to quench DL on the 100 µs-10 ms scale, probably via inhibition of reverse electron transfer at the Fe/S centers in Complex I, and (3) the relative insensitivity of DL to intracellular OH• and H2O2 levels.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Peróxido de Hidrógeno/toxicidad , Quercetina/farmacología , Vitamina K 3/farmacología , Proteínas de Ciclo Celular/metabolismo , Citometría de Flujo , Humanos , Células Jurkat , Cinética , Leucemia/tratamiento farmacológico , Leucemia/patología , Espectrometría de Fluorescencia
16.
Neurosci Lett ; 473(1): 52-5, 2010 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-20156525

RESUMEN

The exposure of primary rat neocortical astroglial cell cultures to acute electromagnetic fields (EMF) in the microwave range was studied. Differentiated astroglial cell cultures at 14 days in vitro were exposed for 5, 10, or 20min to either 900MHz continuous waves or 900MHz waves modulated in amplitude at 50Hz using a sinusoidal waveform and 100% modulation index. The strength of the electric field (rms value) at the sample position was 10V/m. No change in cellular viability evaluated by MTT test and lactate dehydrogenase release was observed. A significant increase in ROS levels and DNA fragmentation was found only after exposure of the astrocytes to modulated EMF for 20min. No evident effects were detected when shorter time intervals or continuous waves were used. The irradiation conditions allowed the exclusion of any possible thermal effect. Our data demonstrate, for the first time, that even acute exposure to low intensity EMF induces ROS production and DNA fragmentation in astrocytes in primary cultures, which also represent the principal target of modulated EMF. Our findings also suggest the hypothesis that the effects could be due to hyperstimulation of the glutamate receptors, which play a crucial role in acute and chronic brain damage. Furthermore, the results show the importance of the amplitude modulation in the interaction between EMF and neocortical astrocytes.


Asunto(s)
Astrocitos/efectos de la radiación , Fragmentación del ADN/efectos de la radiación , Microondas , Especies Reactivas de Oxígeno/metabolismo , Animales , Animales Recién Nacidos , Astrocitos/metabolismo , Campos Electromagnéticos , Neocórtex/citología , Neocórtex/metabolismo , Neocórtex/efectos de la radiación , Ratas , Ratas Wistar
17.
Indian J Exp Biol ; 46(5): 364-70, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18697621

RESUMEN

Measurements of impedance spectroscopy and delayed luminescence have been performed on the acupuncture points PC4 and PC8 and other two control points of ten volunteers. The results show that there is a highly significant difference between the imaginary parts of the impedance of the acupunctural points and that of the control points. The same difference has not be observed in the values of the total number of counts of delayed luminescence. However a relationship has been detected between the imaginary part of the impedance of PC8 point and the total number of delayed luminescence counts, similar to that one found before for collagen, and it has been seen that the temporal dynamics of the two phenomena measured on one control points are similar. In particular, these final results confirm the close connection between the delayed luminescence and the dielectric properties of biological tissues.


Asunto(s)
Acupuntura/métodos , Impedancia Eléctrica , Mediciones Luminiscentes/métodos , Puntos de Acupuntura , Adulto , Biofisica/métodos , Conductividad Eléctrica , Humanos , Persona de Mediana Edad , Modelos Anatómicos , Probabilidad , Piel/patología , Factores de Tiempo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...