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1.
Sci Rep ; 11(1): 4142, 2021 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-33602989

RESUMO

Gamma radiation produces DNA instability and impaired phenotype. Previously, we observed negative effects on phenotype, DNA methylation, and gene expression profiles, in offspring of zebrafish exposed to gamma radiation during gametogenesis. We hypothesize that previously observed effects are accompanied with changes in the expression profile of non-coding RNAs, inherited by next generations. Non-coding RNA expression profile was analysed in F1 offspring (5.5 h post-fertilization) by high-throughput sequencing 1 year after parental irradiation (8.7 mGy/h, 5.2 Gy total dose). Using our previous F1-γ genome-wide gene expression data (GSE98539), hundreds of mRNAs were predicted as targets of differentially expressed (DE) miRNAs, involved in pathways such as insulin receptor, NFkB and PTEN signalling, linking to apoptosis and cancer. snRNAs belonging to the five major spliceosomal snRNAs were down-regulated in the F1-γ group, Indicating transcriptional and post-transcriptional alterations. In addition, DEpiRNA clusters were associated to 9 transposable elements (TEs) (LTR, LINE, and TIR) (p = 0.0024), probable as a response to the activation of these TEs. Moreover, the expression of the lincRNAs malat-1, and several others was altered in the offspring F1, in concordance with previously observed phenotypical alterations. In conclusion, our results demonstrate diverse gamma radiation-induced alterations in the ncRNA profiles of F1 offspring observable 1 year after parental irradiation.


Assuntos
Raios gama/efeitos adversos , RNA não Traduzido/genética , Peixe-Zebra/genética , Animais , Dano ao DNA/genética , Dano ao DNA/efeitos da radiação , Metilação de DNA/genética , Metilação de DNA/efeitos da radiação , Gametogênese/genética , Gametogênese/efeitos da radiação , Transdução de Sinais/genética , Transdução de Sinais/efeitos da radiação , Transcriptoma/genética , Transcriptoma/efeitos da radiação
2.
Lasers Med Sci ; 36(6): 1169-1175, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32996021

RESUMO

Although it was demonstrated that curcumin-mediated antimicrobial photodynamic therapy (aPDT) is effective for reducing the viability of microbial cells and the vitality of oral biofilms, the cytotoxicity of this therapeutic approach for host cells has not been yet elucidated. Hence, the aim of this study was to evaluate the cytotoxicity and apoptotic effects of curcumin-mediated aPDT on mouse fibroblasts. Cells were treated with 0.6 or 6 µmol.L-1 curcumin combined with 0.075 or 7.5 J.cm-2 LED at 455 nm. Cytotoxicity was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and crystal violet (CV) assays, while quantitative reverse transcriptase-PCR (qRT-PCR) was used to assess the expression of Bax, Bad, Bcl-2, VDAC-1, cytochrome C, and Fas-L genes for apoptosis. The differences between groups were detected by Kruskal-Wallis and post hoc Dunn's tests for MTT and CV assays and by ANOVA and post hoc Tukey test for qRT-PCR (P < 0.05). The effect of 0.6 µmol.L-1 curcumin plus 0.075 J.cm-2 LED (minimum parameter) did not differ statistically from control group; however, the combination of 0.6 µmol.L-1 curcumin plus 7.5 J.cm-2 LED reduced viable cells in 34%, while the combinations of 6 µmol.L-1 curcumin plus 0.075 and 7.5 J.cm-2 LED reduced viable cells in 47% and 99%, respectively. aPDT increased significantly the relative expression of Bax/Bcl-2, cytochrome C, VDAC-1, and Fas-L genes, without influence on the ratio Bad/Bcl-2. Therefore, curcumin-mediated aPDT activated Bcl-2 apoptosis signaling pathways in mouse fibroblasts regarding present conditions, reducing the viability of cells with the increase of curcumin concentrations and light energies.


Assuntos
Anti-Infecciosos/farmacologia , Apoptose/efeitos dos fármacos , Curcumina/farmacologia , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fotoquimioterapia , Transdução de Sinais/efeitos dos fármacos , Animais , Apoptose/efeitos da radiação , Fibroblastos/efeitos da radiação , Camundongos , Transdução de Sinais/efeitos da radiação
3.
Int J Radiat Biol ; 97(2): 149-155, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33253600

RESUMO

PURPOSE: DNA damage is one of the main consequences of exposure to ionizing irradiation (IR). Recent studies indicate that IR can modulate the expression of immune system-related genes. However, the effects of IR on the expression of genes and pathways of the B7-CD28 superfamily remain poorly defined. The aim of this study was to evaluate the modulation of genes and pathways related to the B7-CD28 superfamily in response to IR. MATERIALS AND METHODS: In this study, we used transcriptome data available from the Gene Expression Omnibus (GEO) database to investigate the modulation of the response of genes and pathways of samples of human peripheral blood irradiated with doses of 150, 300, and 600 cGy. The data were obtained at 6 and 24 h after irradiation. The relationship between genes and pathways was established through the Reactome database. The behavior of these pathways was analyzed using mathematical methods based on relative activity and diversity. Analysis of variance (ANOVA) followed by multiple comparisons tests (Bonferroni and Tamhanes) was used to identify differentially expressed genes. Data on transcriptomes were analyzed through ViaComplex V.1.0 and IBM SPSS Statistics 22. RESULTS: For the pathways investigated in this study, we observed that the effects produced by these doses significantly modified the behavior of five pathways associated with the immune system. Also, the dose of 300 cGy might trigger signaling for the activation of T cells through the negative regulation (p < .05) of the co-inhibitory PDCD1LG2 gene. Positive regulation caused by 300 cGy (p < .05) of the CD80 receptor was observed by us, which might be related to a stimulatory signal. According to our findings, this dose induced the production of cytokines and genes that are associated with the activation and differentiation of T cells. CONCLUSIONS: Our findings indicate that the irradiation modulated the organization of the biological system, suggesting that 300 cGy is more efficient in activating the immune system.


Assuntos
Antígenos B7/genética , Células Sanguíneas/efeitos da radiação , Antígenos CD28/genética , Antígenos B7/fisiologia , Células Sanguíneas/imunologia , Antígenos CD28/fisiologia , Feminino , Expressão Gênica/efeitos da radiação , Humanos , Masculino , Transdução de Sinais/efeitos da radiação
4.
PLoS One ; 15(8): e0236727, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32750068

RESUMO

Low-power laser irradiation (LPLI) is clinically used to modulate inflammation, proliferation and apoptosis. However, its molecular mechanisms are still not fully understood. This study aimed to describe the effects of LPLI upon inflammatory, apoptotic and proliferation markers in submandibular salivary glands (SMGs) in an experimental model of chronic disorder, 24h after one time irradiation. Diabetes was induced in rats by the injection of streptozotocin. After 29 days, these animals were treated with LPLI in the SMG area, and euthanized 24h after this irradiation. Treatment with LPLI significantly decreased diabetes-induced high mobility group box 1 (HMGB1) and tumor necrosis factor alpha (TNF-α) expression, while enhancing the activation of the transcriptional factor cAMP response element binding (CREB) protein. LPLI also reduced the expression of bax, a mitochondrial apoptotic marker, favoring the cell survival. These findings suggest that LPLI can hamper the state of chronic inflammation and favor homeostasis in diabetic rats SMGs.


Assuntos
Diabetes Mellitus Experimental/radioterapia , Terapia com Luz de Baixa Intensidade , Transdução de Sinais/efeitos da radiação , Glândula Submandibular/efeitos da radiação , Animais , Apoptose , AMP Cíclico/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Feminino , Proteína HMGB1/genética , Proteína HMGB1/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Fosforilação , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Fator de Necrose Tumoral alfa/metabolismo
5.
Semin Radiat Oncol ; 30(2): 173-180, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32381296

RESUMO

Immune checkpoint inhibitors have shown remarkable clinical benefit across a variety of cancer types. However, the majority of patients do not respond or develop relapse after therapy. Radiation can favorably modulate the immune system and enhance tumor antigen recognition and rejection. Thus, the combination of radiation and immune checkpoint blockade (ICB) has been recognized as a promising strategy to improve tumor response and broaden the clinical utility of immunotherapy. In this review, we highlight the preclinical and clinical experience at our institution aimed at understanding and promoting the immunostimulatory effect of radiation. We discuss the rationale, design, results, and lessons from our clinical trials in combining radiation with anti-CTLA4 and/or anti-PD-1 therapy. In parallel, our studies to understand the resistance mechanism to radiation and ICB have converged on interferon (IFN) signaling as a key regulatory pathway. Persistent IFN-γ signaling impairs anti-tumor immune responses which can be reversed by using JAK inhibitor to disrupt the IFN signaling. Lastly we discuss remaining challenges, ongoing studies, and future directions in combining radiation with immunotherapy.


Assuntos
Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias/imunologia , Neoplasias/radioterapia , Animais , Anticorpos Monoclonais/uso terapêutico , Antígenos de Neoplasias/imunologia , Ensaios Clínicos como Assunto , Terapia Combinada , Humanos , Imunoterapia/métodos , Interferons/imunologia , Pennsylvania , Projetos de Pesquisa , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/efeitos da radiação
6.
Photochem Photobiol Sci ; 18(10): 2363-2373, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31290528

RESUMO

Sunlight is a ubiquitous environmental stimulus for the great majority of living organisms on Earth; therefore it is logical to expect the development of "seeing mechanisms" which lead them to successfully adapt to particular ecological niches. Although these mechanisms were recognized in photosynthetic organisms, it was not until recent years that the scientific community found out about light perception in chemotrophic ones. In this review we summarize the current knowledge about the mechanism of light sensing through the blue light receptor BlsA in Acinetobacter baumannii. We highlight its function as a global regulator that pleiotropically modulates a large number of physiological processes, many of which are linked to the ability of this opportunist pathogen to persist in adverse intrahospital environments. Moreover, we describe with some specific examples the molecular basis of how this photoregulator senses blue light and translates this physical signal by modulating gene expression of target regulons. Finally, we discuss the possible course of these investigations needed to dissect this complex regulatory network, which ultimately will help us better understand the A. baumannii physiology.


Assuntos
Acinetobacter baumannii/fisiologia , Proteínas de Bactérias/metabolismo , Luz , Transdução de Sinais/efeitos da radiação , Acetoína/metabolismo , Acinetobacter baumannii/efeitos da radiação , Flavina-Adenina Dinucleotídeo/sangue , Temperatura , Virulência
7.
PLoS One ; 13(10): e0205015, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30273391

RESUMO

Channelopsins and photo-regulated ion channels make it possible to use light to control electrical activity of cells. This powerful approach has lead to a veritable explosion of applications, though it is limited to changing membrane voltage of the target cells. An enormous potential could be tapped if similar opto-genetic techniques could be extended to the control of chemical signaling pathways. Photopigments from invertebrate photoreceptors are an obvious choice-as they do not bleach upon illumination -however, their functional expression has been problematic. We exploited an unusual opsin, pScop2, recently identified in ciliary photoreceptors of scallop. Phylogenetically, it is closer to vertebrate opsins, and offers the advantage of being a bi-stable photopigment. We inserted its coding sequence and a fluorescent protein reporter into plasmid vectors and demonstrated heterologous expression in various mammalian cell lines. HEK 293 cells were selected as a heterologous system for functional analysis, because wild type cells displayed the largest currents in response to the G-protein activator, GTP-γ-S. A line of HEK cells stably transfected with pScop2 was generated; after reconstitution of the photopigment with retinal, light responses were obtained in some cells, albeit of modest amplitude. In native photoreceptors pScop2 couples to Go; HEK cells express poorly this G-protein, but have a prominent Gq/PLC pathway linked to internal Ca mobilization. To enhance pScop2 competence to tap into this pathway, we swapped its third intracellular loop-important to confer specificity of interaction between 7TMDRs and G-proteins-with that of a Gq-linked opsin which we cloned from microvillar photoreceptors present in the same retina. The chimeric construct was evaluated by a Ca fluorescence assay, and was shown to mediate a robust mobilization of internal calcium in response to illumination. The results project pScop2 as a potentially powerful optogenetic tool to control signaling pathways.


Assuntos
Luz , Opsinas/metabolismo , Transdução de Sinais/efeitos da radiação , Sequência de Aminoácidos , Animais , Cálcio/metabolismo , Carbacol/farmacologia , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/química , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/metabolismo , Células HEK293 , Humanos , Potenciais da Membrana , Opsinas/classificação , Opsinas/genética , Técnicas de Patch-Clamp , Pectinidae/metabolismo , Filogenia , Domínios Proteicos , Retina/metabolismo , Retina/patologia , Alinhamento de Sequência , Transdução de Sinais/efeitos dos fármacos , Fosfolipases Tipo C/metabolismo
8.
Braz J Med Biol Res ; 51(12): e7862, 2018 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-30365726

RESUMO

Although the effects of low-intensity pulsed ultrasound (LIPUS) on diverse cell types have been fully studied, the functional role of LIPUS in keratinocytes remains poorly understood. This study aimed to investigate the effects of LIPUS on proliferation and migration of HaCaT cells as well as the regulatory mechanisms associated with signaling pathways. Human HaCaT cells were exposed or not to LIPUS, and cell proliferation and migration were measured by BrdU incorporation assay and Transwell assay, respectively. Expression of proteins associated with proliferation and migration was evaluated by western blot analysis. Expression of key kinases in the PI3K/AKT and JNK pathways was also evaluated by western blot analysis. Effects of LIPUS on the PI3K/AKT and JNK pathways, and whether LIPUS affected HaCaT cells via these two pathways were finally explored. When the parameter of LIPUS (number of cycles) was set at 300, cell viability was the highest after LIPUS stimulation. We then found that the percentage of BrdU positive cells was enhanced by LIPUS, along with up-regulation of cyclinD1, CDK6, CDK4, and VEGF. LIPUS promoted migration, as well as up-regulation of MMP-2 and MMP-9. Phosphorylation levels of key kinases in the PI3K/AKT and JNK pathways were increased by LIPUS. Inhibition of either PI3K/AKT pathway or JNK pathway attenuated effects of LIPUS on HaCaT cells, and co-inhibition of these two pathways showed augmented effects. LIPUS promoted proliferation and migration of HaCaT cells through activating the PI3K/AKT and JNK pathways.


Assuntos
Movimento Celular/efeitos da radiação , Proliferação de Células/efeitos da radiação , Queratinócitos/efeitos da radiação , Sistema de Sinalização das MAP Quinases/efeitos da radiação , Fosfatidilinositol 3-Quinases/efeitos da radiação , Proteínas Proto-Oncogênicas c-akt/efeitos da radiação , Ondas Ultrassônicas , Análise de Variância , Western Blotting , Bromodesoxiuridina , Linhagem Celular Transformada , Sobrevivência Celular/efeitos da radiação , Humanos , Queratinócitos/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Reprodutibilidade dos Testes , Transdução de Sinais/efeitos da radiação , Regulação para Cima
9.
Clin Transl Oncol ; 20(8): 975-988, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29318449

RESUMO

Every year, millions of cancer patients undergo radiation therapy for treating and destroying abnormal cell growths within normal cell environmental conditions. Thus, ionizing radiation can have positive therapeutic effects on cancer cells as well as post-detrimental effects on surrounding normal tissues. Previous studies in the past years have proposed that the reduction and oxidation metabolism in cells changes in response to ionizing radiation and has a key role in radiation toxicity to normal tissue. Free radicals generated from ionizing radiation result in upregulation of cyclooxygenases (COXs), nitric oxide synthase (NOSs), lipoxygenases (LOXs) as well as nicotinamide adenine dinucleotide phosphate oxidase (NADPH oxidase), and their effected changes in mitochondrial functions are markedly noticeable. Each of these enzymes is diversely expressed in multiple cells, tissues and organs in a specific manner. Overproduction of reactive oxygen radicals (ROS), reactive hydroxyl radical (ROH) and reactive nitrogen radicals (RNS) in multiple cellular environments in the affected nucleus, cell membranes, cytosol and mitochondria, and other organelles, can specifically affect the sensitive and modifying enzymes of the redox system and repair proteins that play a pivotal role in both early and late effects of radiation. In recent years, ionizing radiation has been known to affect the redox functions and metabolism of NADPH oxidases (NOXs) as well as having destabilizing and detrimental effects on directly and indirectly affected cells, tissues and organs. More noteworthy, chronic free radical production may continue for years, increasing the risk of carcinogenesis and other oxidative stress-driven degenerative diseases as well as pathologies, in addition to late effect complications of organ fibrosis. Hence, knowledge about the mechanisms of chronic oxidative damage and injury in affected cells, tissues and organs following exposure to ionizing radiation may help in the development of treatment and management strategies of complications associated with radiotherapy (RT) or radiation accident victims. Thus, this medically relevant phenomenon may lead to the discovery of potential antioxidants and inhibitors with promising results in targeting and modulating the ROS/NO-sensitive enzymes in irradiated tissues and organ injury systems.


Assuntos
Antioxidantes/farmacologia , Neoplasias/tratamento farmacológico , Estresse Oxidativo/efeitos da radiação , Radiação Ionizante , Espécies Reativas de Oxigênio/metabolismo , Animais , Humanos , Oxirredução , Transdução de Sinais/efeitos da radiação
10.
Braz. j. med. biol. res ; 51(12): e7862, 2018. graf
Artigo em Inglês | LILACS | ID: biblio-974259

RESUMO

Although the effects of low-intensity pulsed ultrasound (LIPUS) on diverse cell types have been fully studied, the functional role of LIPUS in keratinocytes remains poorly understood. This study aimed to investigate the effects of LIPUS on proliferation and migration of HaCaT cells as well as the regulatory mechanisms associated with signaling pathways. Human HaCaT cells were exposed or not to LIPUS, and cell proliferation and migration were measured by BrdU incorporation assay and Transwell assay, respectively. Expression of proteins associated with proliferation and migration was evaluated by western blot analysis. Expression of key kinases in the PI3K/AKT and JNK pathways was also evaluated by western blot analysis. Effects of LIPUS on the PI3K/AKT and JNK pathways, and whether LIPUS affected HaCaT cells via these two pathways were finally explored. When the parameter of LIPUS (number of cycles) was set at 300, cell viability was the highest after LIPUS stimulation. We then found that the percentage of BrdU positive cells was enhanced by LIPUS, along with up-regulation of cyclinD1, CDK6, CDK4, and VEGF. LIPUS promoted migration, as well as up-regulation of MMP-2 and MMP-9. Phosphorylation levels of key kinases in the PI3K/AKT and JNK pathways were increased by LIPUS. Inhibition of either PI3K/AKT pathway or JNK pathway attenuated effects of LIPUS on HaCaT cells, and co-inhibition of these two pathways showed augmented effects. LIPUS promoted proliferation and migration of HaCaT cells through activating the PI3K/AKT and JNK pathways.


Assuntos
Queratinócitos/efeitos da radiação , Movimento Celular/efeitos da radiação , Fosfatidilinositol 3-Quinases/efeitos da radiação , Sistema de Sinalização das MAP Quinases/efeitos da radiação , Proliferação de Células/efeitos da radiação , Ondas Ultrassônicas , Bromodesoxiuridina , Linhagem Celular Transformada , Transdução de Sinais/efeitos da radiação , Queratinócitos/metabolismo , Regulação para Cima , Sobrevivência Celular/efeitos da radiação , Western Blotting , Reprodutibilidade dos Testes , Análise de Variância , Fosfatidilinositol 3-Quinases/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo
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