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1.
Elife ; 102021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34545808

RESUMO

In fluctuating environments, switching between different growth strategies, such as those affecting cell size and proliferation, can be advantageous to an organism. Trade-offs arise, however. Mechanisms that aberrantly increase cell size or proliferation-such as mutations or chemicals that interfere with growth regulatory pathways-can also shorten lifespan. Here we report a natural example of how the interplay between growth and lifespan can be epigenetically controlled. We find that a highly conserved RNA-modifying enzyme, the pseudouridine synthase Pus4/TruB, can act as a prion, endowing yeast with greater proliferation rates at the cost of a shortened lifespan. Cells harboring the prion grow larger and exhibit altered protein synthesis. This epigenetic state, [BIG+] (better in growth), allows cells to heritably yet reversibly alter their translational program, leading to the differential synthesis of dozens of proteins, including many that regulate proliferation and aging. Our data reveal a new role for prion-based control of an RNA-modifying enzyme in driving heritable epigenetic states that transform cell growth and survival.


Cells make different proteins to perform different tasks. Each protein is a long chain of building blocks called amino acids that must fold into a particular shape before it can be useful. Some proteins can fold in more than one way, a normal form and a 'prion' form. Prions are unusual in that they can force normally folded proteins with the same amino acid sequence as them to refold into new prions. This means that a single prion can make many more that are inherited when cells divide. Some prions can cause disease, but others may be beneficial. Pus4 is a yeast protein that is typically involved in modifying ribonucleic acids, molecules that help translate genetic information into new proteins. Sometimes Pus4 can adopt a beneficial prion conformation called [BIG+]. When yeast cells have access to plenty of nutrients, [BIG+] helps them grow faster and larger, but this comes at the cost of a shorter lifespan. Garcia, Campbell et al. combined computational modeling and experiments in baker's yeast (Saccharomyces cerevisiae) to investigate the role of [BIG+]. They found that the prion accelerated protein production, leading to both faster growth and a shorter lifespan in these cells, even without any changes in gene sequence. Garcia, Campbell et al.'s findings explain the beneficial activity of prion proteins in baker's yeast cells. The results also describe how cells balance a tradeoff between growth and lifespan without any changes in the genome. This helps to highlight that genetics do not always explain the behaviors of cells, and further methods are needed to better understand cell biology.


Assuntos
Proliferação de Células , Transferases Intramoleculares/metabolismo , Meiose , Proteínas Priônicas/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/enzimologia , Crescimento Celular , Epigênese Genética , Regulação Enzimológica da Expressão Gênica , Regulação Fúngica da Expressão Gênica , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Transferases Intramoleculares/genética , Longevidade , Proteínas Priônicas/genética , Biossíntese de Proteínas , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Proteínas de Saccharomyces cerevisiae/genética , Fatores de Tempo
2.
STAR Protoc ; 2(1): 100349, 2021 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-33665629

RESUMO

Hsp70 inhibitors have great potential as chemical probes and anticancer agents. Thus, it is important to elucidate their modes of action on cancer cell death. This protocol describes a step-by-step process for the synthesis of apoptozole as an inhibitor of Hsp70, analysis of internalization of apoptozole into lysosomes, and assessment of lysosomal membrane permeabilization induced by apoptozole. The current protocol can be used for detailed mechanistic studies of Hsp70 inhibitors and further substances targeting lysosomal proteins on cancer cell death. For complete information on the use and execution of this protocol, please refer to Park et al. (2018).


Assuntos
Antineoplásicos , Proteínas de Choque Térmico HSP70/antagonistas & inibidores , Membranas Intracelulares/metabolismo , Lisossomos/metabolismo , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proteínas de Choque Térmico HSP70/metabolismo , Humanos , Permeabilidade
3.
Artigo em Inglês | MEDLINE | ID: mdl-30195088

RESUMO

The interaction between ocean warming, hypoxia and hypercapnia, suggested by climate projections, may push an organism earlier to the limits of its thermal tolerance window. In a previous study on juveniles of green abalone (Haliotis fulgens), combined exposure to hypoxia and hypercapnia during heat stress induced a lowered critical thermal maximum (CTmax), indicated by constrained oxygen consumption, muscular spams and loss of attachment. Thus, the present study investigated the cell physiology in foot muscle of H. fulgens juveniles exposed to acute warming (18 °C to 32 °C at +3 °C day-1) under hypoxia (50% air saturation) and hypercapnia (~1000 µatm PCO2), alone and in combination, to decipher the mechanisms leading to functional loss in this tissue. Under exposure to either hypoxia or hypercapnia, citrate synthase (CS) activity decreased with initial warming, in line with thermal compensation, but returned to control levels at 32 °C. The anaerobic enzymes lactate and tauropine dehydrogenase increased only under hypoxia at 32 °C. Under the combined treatment, CS overcame thermal compensation and remained stable overall, indicating active mitochondrial regulation under these conditions. Limited accumulation of anaerobic metabolites indicates unchanged mode of energy production. In all treatments, upregulation of Hsp70 mRNA was observed already at 30 °C. However, lack of evidence for Hsp70 protein accumulation provides only limited support to thermal denaturation of proteins. We conclude that under combined hypoxia and hypercapnia, metabolic depression allowed the H. fulgens musculature to retain an aerobic mode of metabolism in response to warming but may have contributed to functional loss.


Assuntos
Metabolismo Energético , Gastrópodes/fisiologia , Regulação da Expressão Gênica no Desenvolvimento , Aquecimento Global , Resposta ao Choque Térmico , Modelos Biológicos , Aminoácido Oxirredutases/química , Aminoácido Oxirredutases/genética , Aminoácido Oxirredutases/metabolismo , Animais , Aquicultura , Dióxido de Carbono/intoxicação , Hipóxia Celular , Citrato (si)-Sintase/química , Citrato (si)-Sintase/genética , Citrato (si)-Sintase/metabolismo , Gastrópodes/classificação , Gastrópodes/crescimento & desenvolvimento , Proteínas de Choque Térmico HSP70/química , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Temperatura Alta/efeitos adversos , L-Lactato Desidrogenase/química , L-Lactato Desidrogenase/genética , L-Lactato Desidrogenase/metabolismo , México , Músculos/fisiologia , Filogenia , Estabilidade Proteica , Distribuição Aleatória
4.
Cell Death Dis ; 9(10): 971, 2018 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-30250167

RESUMO

Chaperone-assisted proteasome degradation of oncogenic protein acts as an upstream signal controlling tumorigenesis and progression. The understanding of the co-regulation of chaperone and oncoprotein of endocytosis pathways is extremely limited. In this study, we showed for the first time that proto-Dbl (dbl proto-oncogene product) is co-enriched with mitochondrial chaperone GRP75 in endocytosis vesicles from ovarian cancer cells. onco-Dbl, produced by oncogenic mutation/degradation of proto-Dbl, markedly enhanced cellular macropinocytosis but suppressed clathrin-mediated endocytosis and clathrin-independent endocytosis pathways, presenting a derailed endocytosis phenotype. GRP75 was associated with proto-Dbl inside cells and modulated Dbl-driven endocytosis derailed by a co-regulatory mode. In spite of not being a component of the Hsc70/Hsp90/proto-Dbl complex, the degradation of proto-Dbl was promoted by GRP75 through the CHIP-mediated ubiquitin-proteasome pathway, of which GRP75 acts as a cooperator with CHIP but also acts as a competitor to Hsc70 and Hsp90 in the multiple chaperones-assisted pro-folding/pro-degradation machinery. Knockdown or inhibition of GRP75 attenuated proto-Dbl degradation and reduced the onco-Dbl level, which differentially impaired Rho GTPases activation and therefore shifted the endocytosis-derailed phenotype. Our data uncovered a novel GRP75-Dbl endocytosis regulatory axis and provided an alternative using chaperone inhibitor to shut down the oncoprotein-driven endocytosis derailment mechanism.


Assuntos
Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Membrana/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina/metabolismo , Animais , Western Blotting , Células COS , Linhagem Celular , Chlorocebus aethiops , Endocitose/genética , Endocitose/fisiologia , Citometria de Fluxo , Células HEK293 , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP90/genética , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Espectrometria de Massas , Proteínas de Membrana/genética , Ligação Proteica , Proto-Oncogene Mas , Transdução de Sinais , Ubiquitina-Proteína Ligases/economia
5.
Environ Sci Pollut Res Int ; 25(20): 20106-20115, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29748799

RESUMO

Quail meat is an emerging source of high-quality animal protein. Quails are exposed to a wide range of xenobiotics such as heavy metals. In this study, residual concentrations of four toxic metals, of significant public health importance, including cadmium (Cd), lead (Pb), arsenic (As), and nickel (Ni), were determined in edible tissues of quails. In addition, metal loads were measured in water, feed, and litter samples collected from same quail farms as possible sources for quail exposure to heavy metals. The possible use of metallothionein (MT) and heat shock protein 70 (Hsp70) as molecular biomarkers of exposure to heavy metals was further investigated. Furthermore, the dietary intake and the potential risk assessment of the examined heavy metals among children and adults were calculated. The edible tissues of quails contained high concentrations of four heavy metals (contents (ppm/ww) ranging from 0.02 to 0.32 in Cd, 0.05 to 1.96 in Pb, 0.002 to 0.32 in As, and 1.17 to 3.94 in Ni), which corresponded to the high contents of these metals in the feeds, water, and litter. MT and Hsp70 mRNA expressions showed positive correlations with the concentrations of heavy metals in tissues indicating the possibility to use these proteins as biomarkers for quail's exposure to toxic metals. Dietary intake of quail meat and risk assessment revealed potential risks especially for children after prolonged exposure to the examined metals. Thus, legislations should be established and continuous screening of metal residues should be adopted in order to reduce the toxic metal concentrations in feeds and drinking water for quails. Reduction of exposure to heavy metals subsequently would lead to minimization of exposure of such toxicants through consumption of quail meat.


Assuntos
Arsênio/análise , Coturnix , Poluentes Ambientais/análise , Contaminação de Alimentos/análise , Carne/análise , Metais Pesados/análise , Ração Animal/análise , Animais , Proteínas Aviárias/genética , Proteínas Aviárias/metabolismo , Biomarcadores/análise , Água Potável/análise , Pisos e Cobertura de Pisos , Expressão Gênica/efeitos dos fármacos , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Humanos , Rim/química , Fígado/química , Masculino , Metalotioneína/genética , Metalotioneína/metabolismo , Músculos/química , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Medição de Risco , Distribuição Tecidual
6.
J Cell Mol Med ; 22(7): 3464-3474, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29704317

RESUMO

Mitochondrial dysfunction is an early feature of Alzheimer's disease (AD) and may play an important role in the pathogenesis of disease. It has been shown that amyloid beta peptide (Aß) and amyloid precursor protein (APP) interact with mitochondria contributing to the mitochondrial dysfunction in AD. Prevention of abnormal protein targeting to mitochondria can protect normal mitochondrial function, increase neuronal survival and at the end, ameliorate symptoms of AD and other neurodegenerative disorders. First steps of mitochondrial protein import are coordinated by molecular chaperones Hsp70 and Hsp90 that bind to the newly synthesized mitochondria-destined proteins and deliver them to the protein import receptors on the surface of organelle. Here, we have described the development of a novel compound named GMP-1 that disrupts interactions between Hsp70/Hsp90 molecular chaperones and protein import receptor Tom70. GMP-1 treatment of SH-SY5Y cells results in decrease in mitochondria-associated APP and protects SH-SY5Y cells from toxic effect of Aß1-42 exposure. Experiments in drosophila and mice models of AD demonstrated neuroprotective effect of GMP-1 treatment, improvement in memory and behaviour tests as well as restoration of mitochondrial function.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Benzimidazóis/farmacologia , Mitocôndrias/efeitos dos fármacos , Chaperonas Moleculares/metabolismo , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/genética , Animais , Animais Geneticamente Modificados , Comportamento Animal/efeitos dos fármacos , Benzimidazóis/uso terapêutico , Modelos Animais de Doenças , Drosophila melanogaster/genética , Glicoproteínas/química , Glicoproteínas/genética , Glicoproteínas/metabolismo , Proteínas de Choque Térmico HSP70/química , Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Choque Térmico HSP90/química , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Camundongos Transgênicos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Proteínas de Transporte da Membrana Mitocondrial/química , Proteínas de Transporte da Membrana Mitocondrial/genética , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Proteínas do Complexo de Importação de Proteína Precursora Mitocondrial , Simulação de Acoplamento Molecular , Atividade Motora/efeitos dos fármacos , Fragmentos de Peptídeos/genética , Proteínas de Ligação a Tacrolimo/química , Proteínas de Ligação a Tacrolimo/genética , Proteínas de Ligação a Tacrolimo/metabolismo
7.
Meat Sci ; 141: 66-80, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29609073

RESUMO

The primary objective of the study was to compare the impact of heat stress on meat production characteristics of Osmanabadi and Salem Black breed goats based on changes in carcass characteristics, meat quality attributes, plasma leptin concentration, skeletal muscle myostatin and heat shock protein 70 (HSP70) gene expression patterns. The goats were randomly distributed into four groups: OSC (n = 6; Osmanabadi Control), OSHS (n = 6; Osmanabadi Heat Stress), SBC (n = 6; Salem Black Control) and SBHS (n = 6; Salem Black Heat Stress). The animals were slaughtered at the end of the study and their meat characteristics were assessed. This study established the impact of heat stress on a wide variety of carcass and meat quality characteristics in OS and SB goat breeds. The results from the study also provided some crucial evidence for a better resilience capacity of Salem Black breed as compared to Osmanabadi goats in maintaining the meat production during heat stress. The study also established plasma leptin and HSP70 genes to be the ideal biomarkers to reflect the impact of heat stress on meat characteristics in indigenous goats.


Assuntos
Composição Corporal/fisiologia , Doenças das Cabras/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Transtornos de Estresse por Calor/veterinária , Leptina/sangue , Músculo Esquelético/química , Animais , Composição Corporal/genética , Cabras/genética , Proteínas de Choque Térmico HSP70/genética , Transtornos de Estresse por Calor/metabolismo
8.
Artigo em Inglês | MEDLINE | ID: mdl-29111472

RESUMO

The goal of this study was to determinate toxicity mechanism of biopesticide with antioxidant enzymes parameters such as superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) and malondialdehyde (MDA) levels, oxidative DNA damage (8-hydroxy-2-deoxyguanosine (8-OHdG)), transcriptional changes of heat shock protein 70 (HSP70), and cytochromes P4501A (CYP1A), sod, cat, and gpx in liver and gill tissues of Oncorhynchus mykiss. For this aim, plant-based (natural pesticides, azadirachtin (AZA)) and synthetic pesticides (deltamethrin (DLM)) were exposed on the fish at different concentrations (0.0005 and 0.00025ppm of DLM; 0.24 and 0.12ppm of AZA) for 21 days. According to the results of the study, the activity of SOD, CAT and GPx decreased, but malondialdehyde (MDA) level and activity of 8-OHdG increased in the gill and liver of rainbow trout (p<0.05). Additionally sod, cat and gpx were down regulated; HSP70 and CYP1A were up regulated for transcriptional observation. The downwards regulation of antioxidant (sod, cat and gpx) and the upregulation of HSP70 and CYP1A was obvious with doses of AZA or DLM (p<0.05). The findings of this study suggest that biopesticide can cause biochemical and physiological effects in the fish gill and liver by causing enzyme inhibition, an increase in 8-OHdG levels and changes in both transcriptional parameters (sod, cat, gpx, HSP70 and CYP1A). We found that excessive doses of plant-based pesticide are nearly as toxic as chemical ones for aquatic organisms. Moreover, 8-OHdG, HSP70 and CYP1A used as a biomarker to determinate toxicity mechanism of biopesticide in aquatic environment.


Assuntos
Antioxidantes/metabolismo , Desoxiguanosina/análogos & derivados , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Limoninas/toxicidade , Nitrilas/toxicidade , Oncorhynchus mykiss/metabolismo , Piretrinas/toxicidade , 8-Hidroxi-2'-Desoxiguanosina , Animais , Hidrocarboneto de Aril Hidroxilases/genética , Hidrocarboneto de Aril Hidroxilases/metabolismo , Catalase , Desoxiguanosina/metabolismo , Relação Dose-Resposta a Droga , Glutationa Peroxidase , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Limoninas/administração & dosagem , Nitrilas/administração & dosagem , Estresse Oxidativo/efeitos dos fármacos , Praguicidas/toxicidade , Piretrinas/administração & dosagem , Superóxido Dismutase , Poluentes Químicos da Água
9.
Environ Pollut ; 224: 54-69, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28222982

RESUMO

The mechanisms underlying cobalt toxicity in aquatic species in general and cnidarians in particular remain poorly understood. Herein we investigated cobalt toxicity in a Hydra model from morphological, histological, developmental, and molecular biological perspectives. Hydra, exposed to cobalt (0-60 mg/L), were altered in morphology, histology, and regeneration. Exposure to standardized sublethal doses of cobalt impaired feeding by affecting nematocytes, which in turn affected reproduction. At the cellular level, excessive ROS generation, as the principal mechanism of action, primarily occurred in the lysosomes, which was accompanied by the upregulation of expression of the antioxidant genes SOD, GST, GPx, and G6PD. The number of Hsp70 and FoxO transcripts also increased. Interestingly, the upregulations were higher in the 24-h than in the 48-h time-point group, indicating that ROS overwhelmed the cellular defense mechanisms at the latter time-point. Comet assay revealed DNA damage. Cell cycle analysis indicated the induction of apoptosis accompanied or not by cell cycle arrest. Immunoblot analyses revealed that cobalt treatment triggered mitochondria-mediated apoptosis as inferred from the modulation of the key proteins Bax, Bcl-2, and caspase-3. From this data, we suggest the use of Hydra as a model organism for the risk assessment of heavy metal pollution in aquatic ecosystems.


Assuntos
Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Cobalto/toxicidade , Dano ao DNA/efeitos dos fármacos , Hydra/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Animais , Antioxidantes/metabolismo , Caspase 3/metabolismo , Ensaio Cometa , Proteínas de Choque Térmico HSP70/metabolismo , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Metais Pesados/toxicidade , Mitocôndrias , Estresse Oxidativo
10.
Chemosphere ; 166: 255-266, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27700992

RESUMO

Sodium fluoride (NaF), one of the most frequently used fluoride compound is composed of Na+ and F-. Apart from its use in water fluoridation, NaF also acts as a major component for different dental products like toothpastes, gels and mouth rinses etc. The present study was carried out to explore the toxic impact of chronic NaF exposure on a non-target organism, Drosophila melanogaster. The larvae exposed to different concentrations of NaF through food showed a significant increase in HSP70 expression both qualitatively and quantitatively. The altered tail length and tail intensity in Comet assay validate the increased DNA damage in treated larvae. The activity of AChE, oxidative stress marker enzymes, phase I and phase II detoxifying enzymes were found to be significantly inhibited in the treated larvae when compared to control though there was no evidence of dose dependent change in each case. The alterations in the mentioned parameters can be due to increased body Fluoride ion (F-) concentration since the analysis with ion electrode analyzer revealed that F- concentration increased significantly with NaF treatment. Hence, the results suggest that D. melanogaster manifest prominent toxic response when subjected to chronic exposure to sub-lethal NaF concentrations.


Assuntos
Drosophila melanogaster/efeitos dos fármacos , Fluoreto de Sódio/toxicidade , Animais , Ensaio Cometa , Sistema Enzimático do Citocromo P-450/metabolismo , Dano ao DNA , Drosophila melanogaster/genética , Fluoretos/toxicidade , Proteínas de Choque Térmico HSP70/metabolismo , Larva/efeitos dos fármacos , Estresse Oxidativo , Fosfatos/toxicidade , beta-Galactosidase/metabolismo
11.
Mol Med Rep ; 14(2): 1594-600, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27356588

RESUMO

Teratospermia is a heterogeneous and complex disorder, which is closely associated with male fertility. Genes and gene products associated with teratospermia may serve as targeted biomarkers that help understand the underlying mechanisms of male infertility; however, systematic information on the subject remains to be elucidated. The present study performed a comparative bioinformatics analysis to identify biomarkers associated with sperm quality, particular focusing on testis­specific biomarkers. A stepwise screening approach identified 1,085 testis/epididymis­specific genes and 3,406 teratospermia­associated genes, resulting in 348 testis­specific genes associated with aberrant sperm quality. These genes were functionally associated with the reproduction process. Gene products corresponding to heat shock protein family A (Hsp70) member 4 like (HSPA4L) and phosphoglycerate kinase 2 were characterized at the cellular level in human testes and ejaculated spermatozoa. HSPA4L expression in sperm was revealed to be associated with sperm quality. The present study provided a novel insight into the understanding of sperm quality, and a potential method for the diagnosis and assessment of sperm quality in the event of male infertility.


Assuntos
Expressão Gênica , Estudos de Associação Genética , Espermatozoides/fisiologia , Testículo/metabolismo , Adulto , Biologia Computacional/métodos , Bases de Dados de Ácidos Nucleicos , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Humanos , Imuno-Histoquímica , Infertilidade Masculina/genética , Masculino , Proteoma , Proteômica/métodos , Teratozoospermia/genética
12.
Artigo em Inglês | MEDLINE | ID: mdl-27371112

RESUMO

This study examined the effects of lab-generated acoustic signals on the behaviour and biochemistry of Mediterranean mussels (Mytilus galloprovincialis). The experiment was carried out in a tank equipped with a video-recording system using six groups of five mussels exposed to five acoustic treatments (each treatment was replicated three times) for 30min. The acoustic signals, with a maximum sound pressure level of 150dB rms re 1µPa, differed in frequency range as follows: low (0.1-5kHz), mid-low (5-10kHz), mid (10-20kHz), mid-high (20-40kHz) and high (40-60kHz). The exposure to sweeps did not produce any significant changes in the mussels' behaviour. Conversely, the specimens exposed to the low frequency band treatment showed significantly higher values of the following biochemical stress parameters measured in their plasma and tissues: glucose, total proteins, total haemocyte number (THC), heat shock protein 70 (Hsp70) expression, and Acetylcholinesterase (AChE) activity. The responses observed in the mussels exposed to low frequency sweeps enable us to suppose a biological and ecological role for this sound, which contains the main frequencies produced by both shipping traffic and the acoustic emissions of fish.


Assuntos
Mytilus/fisiologia , Acetilcolinesterase/metabolismo , Estimulação Acústica , Acústica , Animais , Comportamento Animal , Ecossistema , Glucose/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Hemócitos/citologia , Hemócitos/imunologia , Hemolinfa/metabolismo , Mytilus/imunologia , Proteínas/metabolismo , Água do Mar , Gravação em Vídeo
13.
Zebrafish ; 13(6): 537-540, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27057799

RESUMO

Genetic manipulations are a vital instrument for the study of embryonic development where to understand how genes work, it is necessary to provoke a loss or gain of function of a particular gene in a spatial and temporal manner. In the zebrafish embryo, the Hsp70 promoter is the most commonly used tool to induce a transient global gene expression of a desired gene, in a temporal manner. However, Hsp70-driven global gene induction presents caveats when studying gene function in a tissue of interest as gene induction in the whole embryo can lead to cell-autonomous and non-cell-autonomous phenotypes. In the current article, we describe an innovative and cost effective protocol to activate Hsp70-dependent expression in a small subset of cells in the zebrafish embryo, by utilizing a localized infrared (IR) laser. Our IR laser set up can be incorporated to any microscope platform without the requirement for expensive equipment. Furthermore, our protocol allows for controlled localized induction of specific proteins under the control of the hsp70 promoter in small subsets of cells. We use the migrating zebrafish sensory lateral line primordium as a model, because of its relative simplicity and experimental accessibility; however, this technique can be applied to any tissue in the zebrafish embryo.


Assuntos
Desenvolvimento Embrionário/efeitos da radiação , Regulação da Expressão Gênica no Desenvolvimento , Técnicas Genéticas , Resposta ao Choque Térmico/genética , Temperatura Alta , Peixe-Zebra/fisiologia , Animais , Desenvolvimento Embrionário/genética , Técnicas Genéticas/economia , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Raios Infravermelhos/efeitos adversos , Lasers , Regiões Promotoras Genéticas , Peixe-Zebra/embriologia , Peixe-Zebra/genética
14.
Am J Obstet Gynecol ; 214(3): 369.e1-8, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26928151

RESUMO

BACKGROUND: The uteroplacental vascular supply is a critical determinant of placental function and fetal growth. Current methods for the in vivo assessment of placental blood flow are limited. OBJECTIVE: We demonstrate the feasibility of the use of contrast-enhanced ultrasound imaging to visualize and quantify perfusion kinetics in the intervillous space of the primate placenta. STUDY DESIGN: Pregnant Japanese macaques were studied at mid second trimester and in the early third trimester. Markers of injury were assessed in placenta samples from animals with or without contrast-enhanced ultrasound exposure (n = 6/group). Human subjects were recruited immediately before scheduled first-trimester pregnancy termination. All studies were performed with maternal intravenous infusion of lipid-shelled octofluoropropane microbubbles with image acquisition with a multipulse contrast-specific algorithm with destruction-replenishment analysis of signal intensity for assessment of perfusion. RESULTS: In macaques, the rate of perfusion in the intervillous space was increased with advancing gestation. No evidence of microvascular hemorrhage or acute inflammation was found in placental villous tissue and expression levels of caspase-3, nitrotyrosine and heat shock protein 70 as markers of apoptosis, nitrative, and oxidative stress, respectively, were unchanged by contrast-enhanced ultrasound exposure. In humans, placental perfusion was visualized at 11 weeks gestation, and preliminary data reveal regional differences in intervillous space perfusion within an individual placenta. By electron microscopy, we demonstrate no evidence of ultrastructure damage to the microvilli on the syncytiotrophoblast after first-trimester ultrasound studies. CONCLUSIONS: Use of contrast-enhanced ultrasound did not result in placental structural damage and was able to identify intervillous space perfusion rate differences within a placenta. Contrast-enhanced ultrasound imaging may offer a safe clinical tool for the identification of pregnancies that are at risk for vascular insufficiency; early recognition may facilitate intervention and improved pregnancy outcomes.


Assuntos
Vilosidades Coriônicas/irrigação sanguínea , Vilosidades Coriônicas/diagnóstico por imagem , Meios de Contraste , Microbolhas , Circulação Placentária , Algoritmos , Animais , Caspase 3/metabolismo , Vilosidades Coriônicas/ultraestrutura , Meios de Contraste/efeitos adversos , Feminino , Proteínas de Choque Térmico HSP70/metabolismo , Humanos , Cinética , Macaca , Microbolhas/efeitos adversos , Gravidez , Primeiro Trimestre da Gravidez/fisiologia , Segundo Trimestre da Gravidez/fisiologia , Terceiro Trimestre da Gravidez/fisiologia , Processamento de Sinais Assistido por Computador , Trofoblastos/ultraestrutura , Tirosina/análogos & derivados , Tirosina/metabolismo , Ultrassonografia
15.
Eur J Trauma Emerg Surg ; 42(1): 67-75, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26038024

RESUMO

PURPOSE: Traumatic insults result in an altered inflammatory response, in which alarmins release has a central role. The impact of haemorrhagic shock intensity on the long-term kinetics of alarmins is not yet fully elucidated. We investigated these aspects in a combined trauma (chest, abdominal, and extremities injury) porcine model with different severities and durations of haemorrhagic shock. METHODS: After induction of combined trauma (tibia fracture, lung contusion, and liver laceration), haemorrhagic shock was induced at different intensities: moderate haemorrhage (MH; n = 15): mean arterial pressure (MAP) <30 ± 5 mmHg [maximum loss of total blood volume (TBVmax): 45 %] for 90 min, and severe haemorrhage (SH; n = 10): MAP <25 ± 5 mmHg (TBVmax 50 %) for 120 min. Resuscitation was performed using a standardized crystalloid infusion protocol. Animals were mechanically ventilated and underwent ICU-monitoring for 48 h (MH) and 48.5 h (SH). Blood samples were collected over the clinical time course, and systemic levels of serum alarmins [High-Mobility Group Protein B-1 (HMGB-1) and Heat Shock Protein 70 (HSP70)] were measured using an ELISA kit. RESULTS: Heart rate, systemic blood pressure, lactate, and base excess were significantly altered as a function of haemorrhagic shock in both trauma groups (MH and SH). Systemic HMGB-1 levels were significantly elevated in both trauma groups when compared to the sham group. Haemorrhagic shock severity and duration were positively correlated with HMGB-1 levels and compared to baseline values, concentrations remained significantly increased in SH when compared to MH. On the other hand, we observed a significant decrease in the systemic HSP70 levels of trauma groups (MH, and SH) when compared to the sham group, which was significantly decreased compared to baseline values in SH over the entire time course. CONCLUSION: Our data show that haemorrhagic shock duration and severity affect the systemic levels of HMGB-1 and HSP70. This early alarmins release after trauma can be used to guide the treatment strategies (e.g. surgical procedures) of polytrauma patients.


Assuntos
Proteína HMGB1/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Traumatismo Múltiplo/metabolismo , Choque Hemorrágico/metabolismo , Alarminas/metabolismo , Animais , Contusões , Soluções Cristaloides , Modelos Animais de Doenças , Hidratação , Soluções Isotônicas , Lacerações , Fígado/lesões , Lesão Pulmonar , Masculino , Traumatismo Múltiplo/complicações , Respiração Artificial , Ressuscitação , Índice de Gravidade de Doença , Choque Hemorrágico/etiologia , Sus scrofa , Suínos , Fraturas da Tíbia
16.
PLoS One ; 10(5): e0126051, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25951604

RESUMO

Heat shock proteins (HSPs) are molecular chaperones involved in many cellular functions. It has been shown that mammalian cytosolic HSP70 binds antigenic peptides mediating the activation of the immune system, and that it plays a determining role in tumour immunogenicity. This suggests that HSP70 may be used for the production of conjugated vaccines. Human and plant HSPs share high sequence similarity and some important biological functions in vitro. In addition, plant HSPs have no endotoxic side effects. Extraction of HSP70 from plants for use as vaccine adjuvant requires enhancing its concentration in plant tissues. In this work, we explored the possibility to produce HSP70 in both transgenic and non-transgenic plants, using alfalfa as a model species. First, a transcriptional analysis of a constitutive and an inducible HSP70 genes was conducted in Arabidopsis thaliana. Then the coding sequence of the inducible form was cloned and introduced into alfalfa by Agrobacterium-mediated transformation, and the accumulation of the protein in leaf tissue of transgenic plants was demonstrated. We also tested diverse alfalfa varieties for heat-inducible expression of endogenous HSP70, revealing variety-specific responses to heat shock.


Assuntos
Proteínas de Choque Térmico HSP70/biossíntese , Temperatura Alta , Medicago sativa/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Arabidopsis/genética , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Transcrição Gênica
17.
Ecotoxicol Environ Saf ; 113: 491-8, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25568939

RESUMO

This study assessed the impacts of atrazine (ATR), chlorpyrifos (CPF) and combined ATR/CPF exposure on the kidney of common carp (Cyprinus carpio L.). The carp were sampled after a 40-d exposure to CPF and ATR, individually or in combination, followed by a 40-d recovery to measure the expression levels of heat shock proteins genes (HSP60, HSP70 and HSP90) and pesticide residues in the kidney tissue. The results revealed that the mRNA and protein levels of HSP60, HSP70 and HSP90 were induced in the kidney of common carp by ATR, CPF, and ATR/CPF mixture. The accumulated amounts of ATR, CPF, and their metabolites in the kidney tissues exhibited dose-dependency. These results exhibited that increasing concentration of ATR and CPF in the environment causes considerable stress for common carp, suggesting that the expression levels of HSP60, HSP70 and HSP90 may act as potential biomarkers for assessing the environmental ATR and CPF risk for carp.


Assuntos
Atrazina/toxicidade , Clorpirifos/toxicidade , Proteínas de Choque Térmico/metabolismo , Rim/efeitos dos fármacos , Resíduos de Praguicidas/toxicidade , Animais , Atrazina/metabolismo , Western Blotting , Carpas , Clorpirifos/metabolismo , Expressão Gênica/efeitos dos fármacos , Proteínas de Choque Térmico HSP70/metabolismo , Rim/metabolismo , Resíduos de Praguicidas/metabolismo , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Medição de Risco , Poluentes Químicos da Água/toxicidade
18.
Animal ; 9(1): 104-9, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25245143

RESUMO

Exercise has been shown to increase mRNA expression of a growing number of genes. The aim of this study was to assess if mRNA expression of the metabolism- and oxidative stress-related genes GLUT4 (glucose transporter 4), COX2 (cyclooxygenase 2), SOD1 (superoxide dismutase 1) and HSP70 (heat shock protein 70) in saliva changes following acute exercise stress in dogs. For this purpose, 12 avalanche dogs of the Italian Military Force Guardia di Finanza were monitored during simulation of a search for a buried person in an artificial avalanche area. Rectal temperature (RT) and saliva samples were collected the day before the trial (T0), immediately after the descent from a helicopter at the onset of a simulated avalanche search and rescue operation (T1), after the discovery of the buried person (T2) and 2 h later (T3). Expressions of GLUT4, SOD1, COX2 and HSP70 were measured by real-time PCR. The simulated avalanche search and rescue operation was shown to exert a significant effect on RT, as well as on the expression of all metabolism- and oxidative stress-related genes investigated, which peaked at T2. The observed expression patterns indicate an acute exercise stress-induced upregulation, as confirmed by the reductions in expression at T3. Moreover, our findings indicate that saliva is useful for assessing metabolism- and oxidative stress-related genes without the need for restraint, which could affect working dog performance.


Assuntos
Cães/fisiologia , Metabolismo Energético/fisiologia , Estresse Oxidativo/genética , Condicionamento Físico Animal/fisiologia , Saliva/metabolismo , Animais , Avalanche , Biomarcadores/análise , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Metabolismo Energético/genética , Transportador de Glucose Tipo 4/genética , Transportador de Glucose Tipo 4/metabolismo , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Masculino , Militares , RNA Mensageiro/metabolismo , Distribuição Aleatória , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Superóxido Dismutase-1 , Regulação para Cima
19.
Nanoscale ; 6(21): 12408-13, 2014 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-25232926

RESUMO

A magnetothermally-responsive nanocarrier was developed for efficient thermo-chemotherapy by combining efficient magnetic hyperthermia (MH) and magnetothermally-facilitated drug release. The effective magnetothermal-response contributed to high enhancement of tumor cell killing by an operating mechanism involving MH-facilitated cellular uptake and Heat Shock Protein over-expression.


Assuntos
Antineoplásicos/química , Materiais Biocompatíveis/química , Sistemas de Liberação de Medicamentos , Sinergismo Farmacológico , Magnetismo , Neoplasias/tratamento farmacológico , Linhagem Celular Tumoral , Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Choque Térmico/metabolismo , Células Hep G2 , Humanos , Hipertermia Induzida , Fenômenos Magnéticos , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Neoplasias/patologia , Polímeros/química , Temperatura , Termogravimetria , Regulação para Cima
20.
Environ Monit Assess ; 186(12): 8961-7, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25240497

RESUMO

Expression of the stress biomarkers 70-kDa heat shock proteins (Hsp70) and manganese superoxide dismutase (MnSOD) was measured as the molecular basis of adaptive response against increased experimental temperatures (32-40 °C for a span of 24-72 h) on the fresh water molluscan species, Bellamya bengalensis (Lamark 1882). The experimental snail specimens were collected during summer and winter seasons from two contrasting wetlands: an ecorestored (free from human interference) site (SI) and other experiencing anthropogenic stresses (SII). The mortality rate of the B. bengalensis and the immunoblotting of MnSOD and Hsp70 of their digestive glands were performed at regular intervals during the period of heat stress. The SI provided a lower stress environment based on physicochemical parameters such as pH, dissolved oxygen (DO), biological oxygen demand (BOD), chemical oxygen demand (COD), and alkalinity for the survival of test species, although both sites experienced mortality due to thermal stresses. The parity in protein expressions displayed a uniform mode of adaptive impact to temperature elevations in both field and laboratory exposure. The Hsp70 expression was minimal at lower thermal stress, but increased with a rise in temperature. It is very likely that higher Hsp70 levels are not directly related to survival or adaptation. In contrast, MnSOD levels appeared to be an indicator of adaptive responses vis-a-vis survival of the animals. So, the expression levels of a universal free radical scavenger like MnSOD are recognized as a potential biomarker in a bioindicator species like Bellamya.


Assuntos
Adaptação Fisiológica/fisiologia , Monitoramento Ambiental/métodos , Gastrópodes/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Superóxido Dismutase/metabolismo , Temperatura , Animais , Água Doce , Estações do Ano , Estresse Fisiológico/fisiologia
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