RESUMEN
Water-filtered infrared A and visible light (wIRA/VIS), shown to reduce chlamydial infections in vitro and in vivo, might represent an innovative therapeutic approach against trachoma, a neglected tropical disease caused by ocular infection with the bacterium C. trachomatis. In this in vivo study, we assessed the impact of wIRA radiation in combination with VIS (wavelength range 595-1400â¯nm, intensity 2100â¯W/m2) on the retina and cornea in a guinea pig animal model of inclusion conjunctivitis. We investigated the effects 19â¯days after wIRA/VIS irradiation by comparing a single and double wIRA/VIS treatment with a sham control. By immunolabeling and western blot analyses of critical heat- and stress-responsive proteins, we could not detect wIRA/VIS-induced changes in their expression pattern. Also, immunolabeling of specific retinal marker proteins revealed no changes in their expression pattern caused by the treatment. Our preclinical study suggests wIRA/VIS as a promising and safe therapeutic tool to treat ocular chlamydial infections.
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Córnea/efectos de la radiación , Proteínas del Ojo/efectos de la radiación , Proteínas de Choque Térmico/efectos de la radiación , Calor , Rayos Infrarrojos , Luz , Retina/efectos de la radiación , Animales , Córnea/metabolismo , Proteínas del Ojo/metabolismo , Cobayas , Proteínas de Choque Térmico/metabolismo , Retina/metabolismo , Tracoma/radioterapia , Tracoma/veterinaria , AguaRESUMEN
AIMS: Electromagnetic fields (EMFs) can act as inducers or mediators of stress response through the production of heat shock proteins (HSPs) that modulate immune response and thymus functions. In this study, we analyzed cellular stress levels in rat thymus after exposure of the rats to a 2.45 GHz radio frequency (RF) using an experimental diathermic model in a Gigahertz Transverse Electromagnetic (GTEM) chamber. MAIN METHODS: In this experiment, we used H&E staining, the ELISA test and immunohistochemistry to examine Hsp70 and Hsp90 expression in the thymus and glucocorticoid receptors (GR) of 64 female SpragueDawley rats exposed individually to 2.45 GHz (at 0, 1.5, 3.0 or 12.0 W power). The 1 g averaged peak and mean SAR values in the thymus and whole body of each rat to ensure that sub-thermal levels of radiation were being reached. KEY FINDINGS: The thymus tissue presented several morphological changes, including increased distribution of blood vessels along with the appearance of red blood cells and hemorrhagic reticuloepithelial cells. Levels of Hsp90 decreased in the thymus when animals were exposed to the highest power level (12 W), but only one group did not show recovery after 24 h. Hsp70 presented no significant modifications in any of the groups. The glucocorticoid receptors presented greater immunomarking on the thymic cortex in exposed animals. SIGNIFICANCE: Our results indicate that non-ionizing sub-thermal radiation causes changes in the endothelial permeability and vascularization of the thymus, and is a tissue-modulating agent for Hsp90 and GR.
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Campos Electromagnéticos , Proteínas de Choque Térmico/biosíntesis , Proteínas de Choque Térmico/efectos de la radiación , Receptores de Glucocorticoides/biosíntesis , Receptores de Glucocorticoides/efectos de la radiación , Timo/metabolismo , Timo/efectos de la radiación , Animales , Temperatura Corporal/efectos de la radiación , Endotelio Vascular/efectos de la radiación , Femenino , Proteínas HSP70 de Choque Térmico/biosíntesis , Proteínas HSP70 de Choque Térmico/efectos de la radiación , Proteínas HSP90 de Choque Térmico/biosíntesis , Proteínas HSP90 de Choque Térmico/efectos de la radiación , Ratas , Ratas Sprague-Dawley , Flujo Sanguíneo Regional/efectos de la radiación , Estrés Fisiológico/efectos de la radiación , Timo/irrigación sanguíneaRESUMEN
A novel experimental system to distinguish between potential thermal and non-thermal effects of electromagnetic fields (EMFs) on the conformational equilibrium and folding kinetics of proteins is presented. The system comprises an exposure chamber installed within the measurement compartment of a spectropolarimeter and allows real-time observation of the circular dichroism (CD) signal of the protein during EMF exposure. An optical temperature probe monitors the temperature of the protein solution at the site of irradiation. The electromagnetic, thermal, and fluid-dynamic behavior of the system is characterized by numerical and experimental means. The number of repeated EMF on/off cycles needed for achieving a certain detection limit is determined on the basis of the experimentally assessed precision of the CD measurements. The isolated thermosensor protein GrpE of the Hsp70 chaperone system of Eschericha coli serves as the test protein. Long-term experiments show high thermal reproducibility as well as thermal stability of the experimental setup.
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Campos Electromagnéticos , Conformación Proteica/efectos de la radiación , Dicroismo Circular , Electroquímica/instrumentación , Proteínas de Escherichia coli/efectos de la radiación , Proteínas de Choque Térmico/efectos de la radiación , Radiación no Ionizante , Reproducibilidad de los Resultados , Termometría/instrumentaciónRESUMEN
PURPOSE: To further evaluate the use of microbeam irradiation (MBI) as a potential means of non-invasive brain tumor treatment by investigating the induction of a bystander effect in non-irradiated tissue. METHODS: Adult rats were irradiated with 35 or 350 Gy at the European Synchotron Research Facility (ESRF), using homogenous (broad beam) irradiation (HI) or a high energy microbeam delivered to the right brain hemisphere only. The proteome of the frontal lobes were then analyzed using two-dimensional electrophoresis (2-DE) and mass spectrometry. RESULTS: HI resulted in proteomic responses indicative of tumourigenesis; increased albumin, aconitase and triosphosphate isomerase (TPI), and decreased dihydrolipoyldehydrogenase (DLD). The MBI bystander effect proteomic changes were indicative of reactive oxygen species mediated apoptosis; reduced TPI, prohibitin and tubulin and increased glial fibrillary acidic protein (GFAP). These potentially anti-tumourigenic apoptotic proteomic changes are also associated with neurodegeneration. However the bystander effect also increased heat shock protein (HSP) 71 turnover. HSP 71 is known to protect against all of the neurological disorders characterized by the bystander effect proteome changes. CONCLUSIONS: These results indicate that the collective interaction of these MBI-induced bystander effect proteins and their mediation by HSP 71, may confer a protective effect which now warrants additional experimental attention.
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Encéfalo/metabolismo , Encéfalo/efectos de la radiación , Efecto Espectador/efectos de la radiación , Proteoma/metabolismo , Proteoma/efectos de la radiación , Secuencia de Aminoácidos , Animales , Apoptosis/efectos de la radiación , Encéfalo/citología , Neoplasias Encefálicas/etiología , Electroforesis en Gel Bidimensional , Proteína Ácida Fibrilar de la Glía/genética , Proteína Ácida Fibrilar de la Glía/metabolismo , Proteína Ácida Fibrilar de la Glía/efectos de la radiación , Proteínas de Choque Térmico/metabolismo , Proteínas de Choque Térmico/efectos de la radiación , Masculino , Datos de Secuencia Molecular , Neoplasias Inducidas por Radiación/etiología , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Proteínas del Tejido Nervioso/efectos de la radiación , Estrés Oxidativo/efectos de la radiación , Prohibitinas , Proteoma/genética , Proteómica , Ratas , Ratas Wistar , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Proteínas Represoras/efectos de la radiación , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Sincrotrones , Triosa-Fosfato Isomerasa/genética , Triosa-Fosfato Isomerasa/metabolismo , Triosa-Fosfato Isomerasa/efectos de la radiación , Tubulina (Proteína)/genética , Tubulina (Proteína)/metabolismo , Tubulina (Proteína)/efectos de la radiaciónRESUMEN
PURPOSE: To investigate whether or not low intensity radio frequency electromagnetic field exposure (RF-EME) associated with mobile phone use can affect human cells, we used a sensitive proteome analysis method to study changes in protein synthesis in cultured human cells. METHODS: Four different cell kinds were exposed to 2 W/kg specific absorption rate in medium containing 35S-methionine/cysteine, and autoradiography of 2D gel spots was used to measure the increased synthesis of individual proteins. RESULTS: While short-term RF-EME did not significantly alter the proteome, an 8-h exposure caused a significant increase in protein synthesis in Jurkat T-cells and human fibroblasts, and to a lesser extent in activated primary human mononuclear cells. Quiescent (metabolically inactive) mononuclear cells, did not detectably respond to RF-EME. Since RF exposure induced a temperature increase of less than 0.15 degrees C, we suggest that the observed cellular response is a so called "athermal" effect of RF-EME. CONCLUSION: Our finding of an association between metabolic activity and the observed cellular reaction to low intensity RF-EME may reconcile conflicting results of previous studies. We further postulate that the observed increased protein synthesis reflects an increased rate of protein turnover stemming from protein folding problems caused by the interference of radio-frequency electromagnetic fields with hydrogen bonds. Our observations do not directly imply a health risk. However, vis-a-vis a synopsis of reports on cells stress and DNA breaks, after short and longer exposure, on active and inactive cells, our findings may contribute to the re-evaluation of previous reports.
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Teléfono Celular , Campos Electromagnéticos , Proteínas de Choque Térmico/efectos de la radiación , Proteoma/análisis , Ondas de Radio/efectos adversos , Relación Dosis-Respuesta en la Radiación , Método Doble Ciego , Electroforesis en Gel Bidimensional , Proteínas de Choque Térmico/metabolismo , Humanos , Imagenología Tridimensional , Espectrometría de Masas , Fracciones SubcelularesRESUMEN
In nematodes, 10 J/m(2)/min of UV irradiation induced a mild reproductive toxicity. Pre-treatment with UV irradiation at 10 J/m(2)/min suppressed the formation of reproductive defects, and activated a noticeable reduction of percentage of population with hsp-16.2::gfp expression, an obvious elevation of superoxide dismutase activities, and decrease of oxidative damage in 50 and 100 microM Cd exposed nematodes; however, pre-treatment with UV irradiation at 20 J/m(2)/min caused a significant decrease of brood sizes or increase of generation times in Cd-exposed nematodes. Pre-treatment with mild UV irradiation did not suppress the formation of reproductive defects in 150 microM Cd-exposed nematodes. Furthermore, the adaptive response to reproductive toxicity from Cd exposure was not observed in a reactive oxygen species sensitive mev-1(kn1) mutant. Therefore, pre-treatment with mild UV irradiation triggers the resistance to reproductive toxicity from Cd exposure by at least partially inducing adaptation to oxidative stress and through a mev-1-dependent pathway.
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Infertilidad/prevención & control , Nematodos/efectos de los fármacos , Nematodos/efectos de la radiación , Reproducción/efectos de los fármacos , Rayos Ultravioleta , Animales , Proteínas de Caenorhabditis elegans/efectos de los fármacos , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/efectos de la radiación , Trastornos del Desarrollo Sexual , Proteínas de Choque Térmico/efectos de los fármacos , Proteínas de Choque Térmico/metabolismo , Proteínas de Choque Térmico/efectos de la radiación , Infertilidad/inducido químicamente , Nematodos/metabolismo , Oviposición/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Estrés Oxidativo/efectos de la radiación , Reproducción/efectos de la radiación , Superóxido Dismutasa/efectos de los fármacos , Superóxido Dismutasa/metabolismo , Superóxido Dismutasa/efectos de la radiaciónRESUMEN
AIM: To determine whether whole of gestation exposure of fetal mouse brain to mobile telephone radiofrequency fields produces a stress response detectable by induction of heat shock proteins (HSPs). METHODS: Using a purpose-designed exposure system at 900 MHz, pregnant mice were given a single, far-field, whole body exposure at a specific absorption rate of 4 W/kg for 60 min/day from day 1 to day 19 of gestation. Control mice were sham-exposed or freely mobile in a cage to control for any stress caused by restraint in the exposure module. Immediately prior to parturition on day 19, fetal brains were collected, fixed in 4% paraformaldehyde and paraffin-embedded. Three coronal sections encompassing a wide range of anatomical regions were cut from each brain and any stress response detected by immunostaining for HSP25, 32 and 70. RESULTS: There was no induction of HSP32 or 70 in any brains, while HSP25 expression was limited to two brainstem nuclei and occurred consistently in exposed and non-exposed brains. CONCLUSION: Whole of gestation exposure of fetal mouse brains to mobile phone radiofrequency fields did not produce any stress response using HSPs as an immunohistochemical marker.
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Encéfalo/efectos de la radiación , Teléfono Celular , Proteínas de Choque Térmico/efectos de la radiación , Efectos Tardíos de la Exposición Prenatal/etiología , Ondas de Radio/efectos adversos , Animales , Encéfalo/metabolismo , Femenino , Feto , Proteínas de Choque Térmico/biosíntesis , Ratones , Ratones Endogámicos BALB C , Embarazo , Estrés Fisiológico/efectos de la radiaciónRESUMEN
BACKGROUND: We recently introduced Renesis, a novel minimally invasive radiofrequency (RF) device, for the treatment of human skin. The wound healing response post-fractional RF (FRF) treatment was examined in human subjects. STUDY DESIGN: The FRF system delivered RF energy directly within the dermis via 5 micro-needle electrode pairs. Tissue temperature was held at 72 degrees C for 4 seconds using an intelligent feedback system. The wound healing response was evaluated histologically and by RT-PCR up to 10 weeks post-RF treatment. Neoelastogenesis and the role of heat shock proteins (HSPs) were assessed by immunohistochemistry. RESULTS: FRF treatment generated a RF thermal zone (RFTZ) pattern in the reticular dermis that consisted of zones of denatured collagen separated by zones of spared dermis. RFTZs were observed through day 28 post-treatment but were replaced by new dermal tissue by 10 weeks. HSP72 expression rapidly diminished after day 2 while HSP47 expression increased progressively through 10 weeks. Reticular dermal volume, cellularity, hyaluronic acid, and elastin content increased. RT-PCR studies revealed an immediate increase in IL-1beta, TNF-alpha, and MMP-13 while MMP-1, HSP72, HSP47, and TGF-beta levels increased by 2 days. We also observed a marked induction of tropoelastin, fibrillin, as well as procollagens 1 and 3 by 28 days post-treatment. CONCLUSION: Our study revealed a vigorous wound healing response is initiated post-treatment, with progressive increase in inflammatory cell infiltration from day 2 through 10 weeks. An active dermal remodeling process driven by the collagen chaperone HSP47 led to complete replacement of RFTZs with new collagen by 10 weeks post-treatment. Furthermore, using both immunohistochemical and PCR studies, we successfully demonstrated for the first time evidence of profound neoelastogenesis following RF treatment of human skin. The combination of neoelastogenesis and neocollagenesis induced by treatment with the FRF system may provide a reliable treatment option for skin laxity and/or rhytids.
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Colágeno/efectos de la radiación , Fraccionamiento de la Dosis de Radiación , Terapia por Luz de Baja Intensidad/métodos , Cicatrización de Heridas/efectos de la radiación , Adulto , Colágeno/metabolismo , Tejido Elástico/metabolismo , Tejido Elástico/patología , Tejido Elástico/efectos de la radiación , Elastina/metabolismo , Elastina/efectos de la radiación , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Proteínas de Choque Térmico/efectos de la radiación , Humanos , Mediadores de Inflamación/metabolismo , Mediadores de Inflamación/efectos de la radiación , Terapia por Luz de Baja Intensidad/instrumentación , Estudios Prospectivos , Cicatrización de Heridas/fisiologíaRESUMEN
Cryptochromes (CRYs) are blue light receptors important for plant growth and development. Comprehensive information on monocot CRYs is currently only available for rice (Oryza sativa). We report here the molecular and functional characterization of two CRY genes, TaCRY1a and TaCRY2, from the monocot wheat (Triticum aestivum). The expression of TaCRY1a was most abundant in seedling leaves and barely detected in roots and germinating embryos under normal growth conditions. The expression of TaCRY2 in germinating embryos was equivalent to that in leaves and much higher than the TaCRY1a counterpart. Transition from dark to light slightly affected the expression of TaCRY1a and TaCRY2 in leaves, and red light produced a stronger induction of TaCRY1a. Treatment of seedlings with high salt, polyethylene glycol, and abscisic acid (ABA) up-regulated TaCRY2 in roots and germinating embryos. TaCRY1a displays a light-responsive nucleocytoplasmic shuttling pattern similar to that of Arabidopsis (Arabidopsis thaliana) CRY1, contains nuclear localization domains in both the N and C termini, and includes information for nuclear export in its N-terminal domain. TaCRY2 was localized to the nucleus in the dark. Expression of TaCRY1a-green fluorescent protein or TaCRY2-green fluorescent protein in Arabidopsis conferred a shorter hypocotyl phenotype under blue light. These transgenic Arabidopsis plants showed higher sensitivity to high-salt, osmotic stress, and ABA treatment during germination and postgermination development, and they displayed altered expression of stress/ABA-responsive genes. The primary root growth in transgenic seedlings was less tolerant of ABA. These observations indicate that TaCRY1 and TaCRY2 might be involved in the ABA signaling pathway in addition to their role in primary blue light signal transduction.
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Flavoproteínas/metabolismo , Morfogénesis/fisiología , Proteínas de Plantas/metabolismo , Triticum/fisiología , Ácido Abscísico/farmacología , Relojes Biológicos , Criptocromos , Flavoproteínas/genética , Proteínas de Choque Térmico/efectos de los fármacos , Proteínas de Choque Térmico/metabolismo , Proteínas de Choque Térmico/efectos de la radiación , Luz , Liasas/metabolismo , Datos de Secuencia Molecular , Morfogénesis/efectos de los fármacos , Morfogénesis/efectos de la radiación , Células Fotorreceptoras/metabolismo , Proteínas de Plantas/genética , Triticum/efectos de los fármacos , Triticum/crecimiento & desarrollo , Triticum/metabolismoAsunto(s)
Proteínas de Choque Térmico/metabolismo , Proteínas de Choque Térmico/efectos de la radiación , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Quinasas de Proteína Quinasa Activadas por Mitógenos/efectos de la radiación , Células Epiteliales/metabolismo , Células Epiteliales/efectos de la radiación , Humanos , Cristalino/metabolismo , Cristalino/efectos de la radiación , Fosforilación/efectos de la radiación , Ondas de RadioRESUMEN
The aim of the present study was to investigate the influence of 50 Hz sinusoidal magnetic field on Hsp27, Hsp70, and Hsp90 expression in a model of primary culture of porcine aortic endothelial cells (PAEC). We took into consideration the Hsp profile in terms of mRNA expression, protein expression and protein localization inside the cells. The choice of the cell system was motivated by the involvement of the endothelial cells in the onset of many diseases; moreover, only few reports describe the effects of extremely low frequency magnetic fields (ELF-MFs) on such cells. ELF-MF exposure induced an increase in the mRNA levels of the three proteins, which was statistically significant for Hsp70. On the contrary, we did not observe any influence on Hsp27, Hsp70, and Hsp90 protein levels. Analysis in situ by immunofluorescence revealed that ELF-MF exposure affected the cellular distribution of Hsp27; in particular a partial relocalization in the nucleus was observed.
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Campos Electromagnéticos/efectos adversos , Endotelio Vascular/efectos de la radiación , Proteínas HSP70 de Choque Térmico/efectos de la radiación , Proteínas HSP90 de Choque Térmico/efectos de la radiación , Proteínas de Choque Térmico/efectos de la radiación , Animales , Células Cultivadas , Endotelio Vascular/citología , Expresión Génica/efectos de la radiación , Proteínas HSP70 de Choque Térmico/biosíntesis , Proteínas HSP90 de Choque Térmico/biosíntesis , Proteínas de Choque Térmico/biosíntesis , ARN Mensajero/metabolismo , ARN Mensajero/efectos de la radiación , Sus scrofaRESUMEN
An in vitro study focusing on the effects of low-level radiofrequency (RF) fields from mobile radio base stations employing the International Mobile Telecommunication 2000 (IMT-2000) cellular system was conducted to test the hypothesis that modulated RF fields act to induce phosphorylation and overexpression of heat shock protein hsp27. First, we evaluated the responses of human cells to microwave exposure at a specific absorption rate (SAR) of 80 mW/kg, which corresponds to the limit of the average whole-body SAR for general public exposure defined as a basic restriction in the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines. Second, we investigated whether continuous wave (CW) and Wideband Code Division Multiple Access (W-CDMA) modulated signal RF fields at 2.1425 GHz induced activation or gene expression of hsp27 and other heat shock proteins (hsps). Human glioblastoma A172 cells were exposed to W-CDMA radiation at SARs of 80 and 800 mW/kg for 2-48 h, and CW radiation at 80 mW/kg for 24 h. Human IMR-90 fibroblasts from fetal lungs were exposed to W-CDMA at 80 and 800 mW/kg for 2 or 28 h, and CW at 80 mW/kg for 28 h. Under the RF field exposure conditions described above, no significant differences in the expression levels of phosphorylated hsp27 at serine 82 (hsp27[pS82]) were observed between the test groups exposed to W-CDMA or CW signal and the sham-exposed negative controls, as evaluated immediately after the exposure periods by bead-based multiplex assays. Moreover, no noticeable differences in the gene expression of hsps were observed between the test groups and the negative controls by DNA Chip analysis. Our results confirm that exposure to low-level RF field up to 800 mW/kg does not induce phosphorylation of hsp27 or expression of hsp gene family.
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Teléfono Celular , Proteínas de Choque Térmico/metabolismo , Proteínas de Choque Térmico/efectos de la radiación , Proteínas de Neoplasias/metabolismo , Proteínas de Neoplasias/efectos de la radiación , Fosforilación/efectos de la radiación , Neoplasias Encefálicas , Línea Celular Tumoral , Exposición a Riesgos Ambientales , Regulación Neoplásica de la Expresión Génica/efectos de la radiación , Glioblastoma , Proteínas de Choque Térmico HSP27 , Proteínas de Choque Térmico/genética , Humanos , Chaperonas Moleculares , Proteínas de Neoplasias/genética , Fosfoserina/metabolismo , Fosfoserina/efectos de la radiaciónRESUMEN
PURPOSE: This study investigated the presence of the 27-kd heat shock protein (HSP27) and its responses to ultraviolet B (UVB) irradiation in human corneal epithelium and in cultured corneal epithelial cells. METHODS: Human corneal epithelial cells including presumed corneal epithelial stem cells were cultured in vitro. HSP27 expression and intracellular localization in normal corneas or cultured corneal cells were examined using immunofluorescence staining. The expression of HSP27 in cultured corneal cells was also detected using western blotting, and the phosphorylated isoforms of HSP27 were identified using isoelectric focusing. RESULTS: In normal corneal tissue, HSP27 was present in limbal basal and suprabasilar epithelial cells. In cultured epithelial corneal cells, HSP27 expression was heterogeneous: Some cells expressed virtually no HSP27 and others showed relatively strong expression. HSP27 was localized to the cytoplasm in nonstressed cells and translocated to the perinuclear and nuclear areas after UVB irradiation. UVB irradiation also induced the phosphorylation of HSP27, resulting in the increase in monophosphorylated isoform and formation of biphosphorylated isoform. UV induced the phosphorylation of HSP27 apparently through activation of p38 mitogen-activated protein kinase. CONCLUSION: HSP27 is present mainly as a nonphosphorylated isoform in corneal epithelium and cultured corneal epithelial cells under nonstressed conditions. The constitutional expression of HSP27 suggests that it plays a physiologic role in the cornea. After UVB irradiation, HSP27 undergoes rapid phosphorylation and translocation. This stress response may be related to a protective role of HSP27 for survival of UVB-exposed corneal cells.
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Epitelio Corneal/efectos de la radiación , Proteínas de Choque Térmico/efectos de la radiación , Proteínas de Neoplasias/efectos de la radiación , Rayos Ultravioleta , Western Blotting , Células Cultivadas , Citoplasma/metabolismo , Epitelio Corneal/metabolismo , Técnica del Anticuerpo Fluorescente Indirecta , Proteínas de Choque Térmico HSP27 , Proteínas de Choque Térmico/metabolismo , Humanos , Punto Isoeléctrico , Chaperonas Moleculares , Proteínas de Neoplasias/metabolismo , Fosforilación , Transporte de Proteínas/efectos de la radiación , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismoRESUMEN
OBJECTIVE: To investigate the effect of low-power laser therapy on levels of stress proteins (SPs) in experimental arthritis and their relation to the bioeffects on arthritic cartilage repair. DESIGN: A total of 42 rats with similar degrees of induced arthritis evaluated by means of bone scan were divided randomly into two groups. In the treated group, 21 rats received helium-neon laser treatment; in the control group, 21 rats received sham laser treatment. The changes in chondrocytes of SPs were measured by electrophoresis of proteins extracted from chondrocytes of arthritic cartilage at various time periods. The histopathologic changes and the presence of SP of arthritic cartilage were identified by hematoxylin and eosin stain and by immunostains of SP72 antibody individually from frozen sections of arthritic cartilage. RESULTS: SP density increased markedly in rats after laser treatment and was closely related to the repair of arthritic cartilage. Furthermore, the pathohistology of arthritic cartilage improved significantly with the decline of SP levels in the follow-up period. CONCLUSION: Helium-neon (632 nm) low-power laser can enhance SP production in arthritic chondrocytes. The extragenic production of SP is well correlated with the therapeutic effect of low-power laser in preserving chondrocytes and the repair of arthritic cartilage in rats.
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Proteínas de Choque Térmico/metabolismo , Terapia por Luz de Baja Intensidad/métodos , Osteoartritis/metabolismo , Osteoartritis/radioterapia , Animales , Cartílago Articular/efectos de la radiación , Condrocitos/metabolismo , Condrocitos/efectos de la radiación , Modelos Animales de Enfermedad , Femenino , Proteínas de Choque Térmico/efectos de la radiación , Helio , Neón , Osteoartritis/patología , Ratas , Ratas WistarRESUMEN
A range of environmental conditions can lead to oxidative stress; thus, a prompt and effective response to oxidative stress is crucial for the survival of plants. Microarray and northern-blot analyses were performed toward the identification of the factors and signaling pathways that enable plants to limit oxidative damage caused by exposure to high light (HL). Arabidopsis plants grown under moderate light (100 micromol m(-2) s(-1)) were exposed to HL (1,000 micromol m(-2) s(-1)) for 1 h. The microarray analyses revealed that exposure of Arabidopsis to HL caused an increase in known antioxidant genes, as well as several unknown genes. Some of these unknown genes had homologies to possible regulatory genes and metabolic enzymes. Furthermore, it was found that a range of chaperones were up-regulated in the HL treatment and that this induction was specifically due to the HL stress. The temporal expression under HL and different oxidative stress conditions of a subset of HL-responsive genes was confirmed via northern-blot analysis. Results from the arrays were also compared with publicly available microarray data sets from a range of different stress conditions at the Arabidopsis Functional Genomics Consortium. This cross comparison enabled the identification of genes that may be induced by changes in redox poise. Finally, to determine if the genes that were differentially expressed by HL stress were under similar transcriptional control, we analyzed the promoter sequences for the presence of common motifs.
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Arabidopsis/efectos de la radiación , Estrés Oxidativo/efectos de la radiación , Antioxidantes/metabolismo , Antioxidantes/efectos de la radiación , Arabidopsis/genética , Arabidopsis/metabolismo , Northern Blotting , Ambiente , Regulación de la Expresión Génica de las Plantas/efectos de la radiación , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/efectos de la radiación , Luz , Chaperonas Moleculares/genética , Chaperonas Moleculares/efectos de la radiación , Análisis de Secuencia por Matrices de Oligonucleótidos , Estrés Oxidativo/genética , Regiones Promotoras Genéticas/genética , Transducción de Señal/genética , Transducción de Señal/efectos de la radiaciónRESUMEN
Ultraviolet B (UVB) irradiation is known to induce activation of cellular stress response pathways in cultured cells or intact human skin, as demonstrated by phosphorylation of MAP kinase family members and up- or down-stream targets, using biochemical assays. This study demonstrates by immunohistochemistry that low-dose UVB irradiation of normal human skin induces rapid and reversible phosphorylation of c-jun (a target of c-jun N-terminal kinase) and p38 mitogen activated protein kinase (p38 MAP kinase). Phosphorylation was maximal at 4-8 h and returned to normal levels at 48 h after irradiation. Nuclear localization of these phosphorylated substrates was found using antisera against the epitope containing the phosphorylated serine-73 of c-jun, and the dually phosphorylated epitope (threonine-180 and tyrosine-182) of p38 MAP kinase. Nearly all epidermal cells were positive for c-jun phosphorylation, whereas p38 phosphorylation was seen predominantly in the differentiated layers. In contrast to the massive activation of c-jun and p38, only a small population of the suprabasal cells showed nuclear translocation of nuclear factor kappa B (NFkappaB), and a few scattered cells became apoptotic, as determined by TUNEL (TdT mediated dUTP nick end labelling) staining. The expression of involucrin and skin-derived anti-leukoproteinase (SKALP)/elafin, two genes putatively under control of the c-jun and p38 pathways, was found to be increased. These findings establish the first cellular localization of UVB-induced protein phosphorylation of stress response proteins in human epidermis, thereby providing a link between cellular activation and gene expression in defined cell populations.
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Queratinocitos/efectos de la radiación , Proteínas Quinasas Activadas por Mitógenos/efectos de la radiación , Proteínas Proto-Oncogénicas c-jun/efectos de la radiación , Piel/efectos de la radiación , Rayos Ultravioleta , Adolescente , Adulto , Células Cultivadas , Relación Dosis-Respuesta en la Radiación , Proteínas de Choque Térmico/efectos de la radiación , Humanos , Inmunohistoquímica , Etiquetado Corte-Fin in Situ , Queratinocitos/enzimología , Queratinocitos/metabolismo , Proteínas Quinasas Activadas por Mitógenos/metabolismo , FN-kappa B/efectos de la radiación , Fosforilación/efectos de la radiación , Proteínas Proto-Oncogénicas c-jun/metabolismo , Piel/citología , Piel/metabolismo , Proteínas Quinasas p38 Activadas por MitógenosRESUMEN
To determine the effects of space radiation on human health for long-term stays in space, we performed 21 space experiments on radiation biology. Two main characteristics of space are microgravity and space radiation that consists of low dose, chronic exposure at low dose-rates, and heavy particles. Through space experiments, we demonstrated the formation of DNA strand breaks, induced mutations, abnormal cell differentiation and the inducible gene expression of a tumor suppressor gene product, p53, in various kinds of organisms. In addition, we investigated the influence of microgravity on radiation-induced biological effects in in vitro biochemical reaction systems and in vivo cell culture systems of bacteria and lower eukaryotes. We review here the importance of radiation biology studies on space radiation from the viewpoints of human health and biological evolution, from the beginning of life until today, in the context of environmental genotoxic radiation.
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Radiación Cósmica , Daño del ADN , Vuelo Espacial , Ingravidez , Medicina Aeroespacial , Animales , Bacterias/efectos de la radiación , Reparación del ADN , Relación Dosis-Respuesta en la Radiación , Proteínas del Choque Térmico HSP72 , Proteínas de Choque Térmico/metabolismo , Proteínas de Choque Térmico/efectos de la radiación , Humanos , Efectividad Biológica Relativa , Proteína p53 Supresora de Tumor/metabolismo , Proteína p53 Supresora de Tumor/efectos de la radiaciónRESUMEN
The release of mitochondrial cytochrome c by genotoxic stress induces the formation of a cytosolic complex with Apaf-1 (mammalian CED4 homolog) and thereby the activation of procaspase-3 (cas-3) and procaspase-9 (cas-9). Here we demonstrate that heat-shock protein 27 (Hsp27) inhibits cytochrome c (cyt c)-dependent activation of cas-3. Hsp27 had no effect on cyt c release, Apaf-1 and cas-9 activation. By contrast, our results show that Hsp27 associates with cas-3, but not Apaf-1 or cas-9, and inhibits activation of cas-3 by cas-9-mediated proteolysis. Furthermore, the present results demonstrate that immunodepletion of Hsp27 depletes cas-3. Importantly, treatment of cells with DNA damaging agents dissociates the Hsp27/cas-3 complex and relieves inhibition of cas-3 activation. These findings define a novel function for Hsp27 and provide the first evidence that a heat shock protein represses cas-3 activation.
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Caspasas/metabolismo , Grupo Citocromo c/metabolismo , Precursores Enzimáticos/metabolismo , Proteínas de Choque Térmico/metabolismo , Actinas/metabolismo , Factor Apoptótico 1 Activador de Proteasas , Caspasa 3 , Caspasa 9 , Caspasas/efectos de los fármacos , Caspasas/inmunología , Línea Celular/efectos de los fármacos , Línea Celular/efectos de la radiación , Sistema Libre de Células , Citarabina/farmacología , Grupo Citocromo c/efectos de los fármacos , Grupo Citocromo c/efectos de la radiación , Citosol/metabolismo , Activación Enzimática , Inhibidores Enzimáticos/farmacología , Precursores Enzimáticos/efectos de los fármacos , Precursores Enzimáticos/inmunología , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/inmunología , Proteínas de Choque Térmico/efectos de la radiación , Humanos , Immunoblotting , Isoenzimas/metabolismo , Metilmetanosulfonato/farmacología , Oligopéptidos/metabolismo , Proteína Quinasa C/metabolismo , Proteína Quinasa C-delta , Proteínas/metabolismo , Estaurosporina/farmacologíaRESUMEN
Activation of the c-Jun N-terminal kinase (JNK) by a variety of stimuli is critical for regulation of many cellular processes including apoptosis. The major inducible heat shock protein Hsp72 has previously been demonstrated to inhibit activation of JNK in cells exposed to heat shock and other protein-damaging agents, thus suppressing apoptosis. Hsp72 can protect proteins from stress-induced damage. To test if this protective function of Hsp72 is involved in JNK suppression, we investigated whether Hsp72 can avert activation of JNK by stimuli that do not cause protein damage. We show that Hsp72 suppresses activation of JNK induced by non-protein-damaging stimuli, interleukin-1 and UV irradiation, as well as by constitutively active components of the JNK signaling cascade Cdc42 and MEKK1. Furthermore, Hsp72 strongly reduced activation of JNK by phosphatase inhibitors. We also demonstrate that an Hsp72 mutant that lacks the ATPase domain is still capable of JNK suppression, thus indicating that the protein refolding activity of Hsp72 is not critical for inhibition of JNK activation. Taken together these data suggest that Hsp72 plays a regulatory role in JNK signaling and that the function of Hsp72 in protein protection or refolding is not involved in JNK regulation.
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Proteínas Quinasas Dependientes de Calcio-Calmodulina/antagonistas & inhibidores , Proteínas de Choque Térmico/metabolismo , Proteínas Quinasas Activadas por Mitógenos , Adenosina Trifosfatasas/metabolismo , Animales , Células COS , Proteínas Quinasas Dependientes de Calcio-Calmodulina/metabolismo , Activación Enzimática , Proteínas del Choque Térmico HSP72 , Proteínas de Choque Térmico/efectos de los fármacos , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/efectos de la radiación , Respuesta al Choque Térmico , Interleucina-1/farmacología , Proteínas Quinasas JNK Activadas por Mitógenos , Pliegue de Proteína , Rayos UltravioletaRESUMEN
We have investigated the modifying effects of epigallocatechin, a major polyphenolic constituent of green tea, on ultraviolet-A-activated gene expression in human fibroblasts and keratinocytes using the stress responsive enzymes: haem oxygenase-1, interstitial collagenase and cyclooxygenase-2. Although epigallocatechin strongly reduced ultraviolet-A-induced haem oxygenase-1 activation in skin-derived 'fibroblasts, the same compound activated collagenase and cyclooxygenase expression. In a keratinocyte cell line, ultraviolet-A-mediated haem oxygenase-1 over-expression was low and epigallocatechin failed to modulate it further. In contrast to the results with fibroblasts, ultraviolet-A activation of cyclooxygenase in keratinocytes was reduced by epigallocatechin. The results indicate that the effect of this green tea polyphenol on cellular stress responses is complex and may involve direct effects on signal transduction as well as changes that may be associated with its antioxidant activity.