Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 157
Filtrar
1.
Int J Mol Sci ; 22(13)2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34201751

RESUMO

Cylindromatosis (CYLD) is a deubiquitinase (DUB) enzyme that was initially characterized as a tumor suppressor of adnexal skin tumors in patients with CYLD syndrome. Later, it was also shown that the expression of functionally inactive mutated forms of CYLD promoted tumor development and progression of non-melanoma skin cancer (NMSC). However, the ability of wild-type CYLD to inhibit skin tumorigenesis in vivo in immunocompetent mice has not been proved. Herein, we generated transgenic mice that express the wild type form of CYLD under the control of the keratin 5 (K5) promoter (K5-CYLDwt mice) and analyzed the skin properties of these transgenic mice by WB and immunohistochemistry, studied the survival and proliferating characteristics of primary keratinocytes, and performed chemical skin carcinogenesis experiments. As a result, we found a reduced activation of the nuclear factor kappa B (NF-κB) pathway in the skin of K5-CYLDwt mice in response to tumor necrosis factor-α (TNF-α); accordingly, when subjected to insults, K5-CYLDwt keratinocytes are prone to apoptosis and are protected from excessive hyperproliferation. Skin carcinogenesis assays showed inhibition of tumor development in K5-CYLDwt mice. As a mechanism of this tumor suppressor activity, we found that a moderate increase in CYLD expression levels reduced NF-κB activation, which favored the differentiation of tumor epidermal cells and inhibited its proliferation; moreover, it decreased tumor angiogenesis and inflammation. Altogether, our results suggest that increased levels of CYLD may be useful for anti-skin cancer therapy.


Assuntos
Carcinoma de Células Escamosas/patologia , Enzima Desubiquitinante CYLD/genética , Neoplasias Cutâneas/patologia , Animais , Carcinoma de Células Escamosas/irrigação sanguínea , Carcinoma de Células Escamosas/genética , Diferenciação Celular/genética , Proliferação de Células/genética , Células Cultivadas , Enzima Desubiquitinante CYLD/metabolismo , Genes Supressores de Tumor , Imunocompetência , Queratinócitos/efeitos dos fármacos , Queratinócitos/patologia , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Camundongos Transgênicos , NF-kappa B/metabolismo , Neovascularização Patológica/genética , Ésteres de Forbol/toxicidade , Neoplasias Cutâneas/irrigação sanguínea , Neoplasias Cutâneas/genética , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/farmacologia
2.
Phytomedicine ; 80: 153340, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33130471

RESUMO

BACKGROUND: Oleanolic acid (OA) is an active compound found in a variety of medicinal herbs and plants. Though OA has been widely attributed with a variety of biological activities, studies focused on its anti-allergic inflammation properties are insufficient. PURPOSE: Given the rapid increase in allergic diseases and the lack of fundamental treatment options, this study aimed to find a safe and effective therapy for allergic disorders. METHODS: We evaluated the inhibitory effect of OA on allergic inflammatory response and the possible mechanisms underlying the effect using phorbol-12-myristate 13-acetate plus calcium ionophore A23187 (PMACI)-stimulated human mast cell (HMC)-1, and a mouse model of compound 48/80-induced anaphylactic shock. RESULTS: OA suppressed pro-inflammatory cytokine expressions in PMACI-induced HMC-1 cells by inhibiting activation of the Akt, p38 mitogen-activated protein kinase (MAPK), nuclear factor-κB (NF-κB), and signal transducer and activator of transcription (STAT) 1 signaling pathways. Moreover, OA showed a protective effect against compound 48/80-induced anaphylactic shock through inhibition of histamine release and immunoglobulin E level via regulation of NF-κB and STAT1 activation. CONCLUSION: The results showed that OA suppressed mast cell-mediated allergic response by transcriptional regulation. We suggest that OA has potential effect against allergic inflammatory disorders, including anaphylaxis, and might be a useful therapeutic agent for allergic disease.


Assuntos
Anafilaxia/prevenção & controle , Antialérgicos/farmacologia , Mastócitos/efeitos dos fármacos , Ácido Oleanólico/farmacologia , Anafilaxia/induzido quimicamente , Animais , Calcimicina/toxicidade , Linhagem Celular , Citocinas/metabolismo , Liberação de Histamina/efeitos dos fármacos , Humanos , Inflamação/tratamento farmacológico , Mediadores da Inflamação/metabolismo , Masculino , Mastócitos/metabolismo , Camundongos Endogâmicos ICR , NF-kappa B/metabolismo , Ésteres de Forbol/toxicidade , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator de Transcrição STAT1/metabolismo , p-Metoxi-N-metilfenetilamina/toxicidade , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
3.
J Ethnopharmacol ; 241: 111970, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31128150

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Jatropha curcas L. is a plant with high cultural significance for quilombola communities of Oriximiná (Pará State, Brazil). Although the plant is highly toxic, its seeds are used in these communities to treat tuberculosis and related diseases and symptoms. AIM OF THE STUDY: This study was designed to provide a scientific rationale for the traditional detoxification method and use of J. curcas seeds in quilombola communities of Oriximiná. MATERIALS AND METHODS: J. curcas seeds were manually separated into testa, tegmen, endosperm, and embryo, and then methanolic extracts of each sample were prepared. The traditional preparation of J. curcas seeds consists of a water extract of endosperms that is known as "milk of pinhão-branco". The content of phorbol esters (PEs) in the extracts was analyzed by High-Performance Liquid Chromatography with Diode-Array Detection (HPLC-DAD). The cytotoxic activity was evaluated in human monocytic cell line THP-1 by Resazurin Reduction Assay, and antimycobacterial activity was assessed by determining Minimal Inhibitory Concentration (MIC) values against H37Rv and BCG strains using the Resazurin Microtiter Assay (REMA). RESULTS: The content analysis revealed that the distribution of PEs within the seeds is not homogeneous. High contents were found in tegmens (4.22 ±â€¯0.25-15.52 ±â€¯0.06 mg/g) and endosperms (1.61 ±â€¯0.07-5.00 ±â€¯0.42 mg/g), while concentrations found in testas and embryos were all below 0.5 mg/g. The traditional preparation derived from the endosperm of J. curcas contained significantly less PEs than the endosperms (0.01 ±â€¯0.005 mg/g). Against THP-1 cells, all the parts of the seed showed cytotoxic activity, while the traditional preparation was considered non-cytotoxic. Nevertheless, only the tegmen and endosperm of J. curcas were considered active against M. tuberculosis and M. bovis (MIC = 200 µg/mL). CONCLUSION: The results of this study indicated that the traditional processing performed by the quilombola people from Oriximiná is effective in reducing the toxicity of J. curcas seeds. Although inactive against mycobacteria, the extensive use of the traditional preparation and its low toxicity encourage further studies to investigate other biological activities.


Assuntos
Jatropha , Medicina Tradicional , Ésteres de Forbol , Extratos Vegetais , Sementes/química , Antibacterianos/análise , Antibacterianos/farmacologia , Antibacterianos/toxicidade , Brasil , Sobrevivência Celular/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Mycobacterium bovis/efeitos dos fármacos , Mycobacterium bovis/crescimento & desenvolvimento , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/crescimento & desenvolvimento , Ésteres de Forbol/análise , Ésteres de Forbol/farmacologia , Ésteres de Forbol/toxicidade , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/toxicidade , Células THP-1
4.
Rev. biol. trop ; 66(2): 495-502, abr.-jun. 2018. tab, graf
Artigo em Inglês | LILACS, SaludCR | ID: biblio-977326

RESUMO

Abstract The tropical and subtropical naturalized physic nut (Jatropha curcas L.), has been explored for biodiesel production in recent times. The oil is extracted from the seeds and, for the production to be feasible, utilization of the residual seed cake is crucial. Although the cake could be employed as a protein source in animal feed, it is rich in phorbol ester, which is toxic for animals. Therefore, breeding programs have been working to reduce or eliminate the phorbol ester content in physic nut. In this context, the present work aimed to evaluate the physic nut oil of toxic and non-toxic varieties (containing known or undetectable amounts of phorbol ester, respectively) with regards to phytotoxicity in a model experiment with Lactuca sativa L. For this, the percentage of germinated seeds was evaluated after 8, 16, 24, 36 and 48 hours of exposure to the treatments with toxic and non-toxic oil at concentrations of 22.5 %, 45 % and 67.5 % of emulsion (physic nut oil energetically mixed with distilled water). Root growth was determined after 48 hours of exposure and the germination speed index was obtained. The different stages of mitotic division as well as possible chromosomal and nuclear alterations were also recorded. The mitotic index was calculated as the number of dividing cells, as a fraction of the total number of cells, and the frequency of chromosome and nuclear alterations, expressed as the percentage of number of alterations divided by the total number of cells. Both varieties exhibited phytotoxicity, inducing significant reductions in percentage of germinated seeds (reduction of 98 %), germination speed index (reduction of 24.44) and root growth (reduction of 8.54 mm). In microscopic analysis, a mitodepressive effect was observed for both oils at the three concentrations used when compared to the negative control; however, it was possible to distinguish between the toxic and the non-toxic varieties based on the more expressive reduction of division promoted by the first, 2.19 %. Significant increments in the frequency of mitotic cells showing chromosome alterations as well, as the presence of condensed nuclei, were observed in the treated cells. However, these parameters were not significantly different from the control in the cells treated with both physic nut oils. In conclusion, the evaluation of root growth and cell division in the plant model L. sativa, can be proposed as an alternative to animal tests to distinguish the varieties with high and low phorbol ester concentration, thus contributing to the detection of toxicity in varieties used in breeding programs.


Resumen Jatropha curcas L., naturalizado tropical y subtropical, ha sido explorado para la producción de biodiesel. El aceite se extrae de las semillas y, para que la producción sea factible, la utilización de la torta de semillas residual es crucial. Aunque la torta se puede emplear como una fuente de proteína en la alimentación animal, es rica en éster de forbol, que es tóxico para los animales. Por lo tanto, los programas de mejoramiento han procurado reducir o eliminar el contenido de éster de forbol de J. curcas. En este contexto, el presente trabajo tuvo como objetivo evaluar el aceite de J. curcas de las variedades tóxicas y no tóxicas (con cantidades conocidas o indetectables de éster de forbol, respectivamente) con respecto a la fitotoxicidad en el modelo Lactuca sativa L. El porcentaje de semillas germinadas se evaluó después de 8, 16, 24, 36 y 48 horas de tratamiento. El crecimiento de la raíz se determinó después de 48 horas de exposición y se obtuvo el índice de velocidad de germinación. Se registraron las diferentes etapas de la división mitótica así como posibles alteraciones cromosómicas y nucleares. El índice mitótico se calculó como el número de células en división como una fracción del número total de células y la frecuencia de las alteraciones cromosómicas y nucleares, expresada como el porcentaje del número de alteraciones dividido entre el número total de células. Ambas variedades exhibieron fitotoxicidad, induciendo reducciones significativas en el porcentaje de semillas germinadas (Reducción del 98 %), índice de velocidad de germinación (Reducción de 24.44) y crecimiento de raíces (Reducción de 8.54 mm). En el análisis microscópico, se observó un efecto mitodepresivo para ambos aceites. Sin embargo, fue posible distinguir entre las variedades tóxicas y las no tóxicas basándose en la reducción más expresiva de la división promovida por la primera, 2.19 %. Se observaron incrementos significativos en la frecuencia de células mitóticas que mostraban alteraciones cromosómicas, así como la presencia de núcleos condensados en las células tratadas. Sin embargo, estos parámetros no fueron significativamente diferentes del control en las células tratadas con ambos aceites de J. curcas. En conclusión, la evaluación del crecimiento de las raíces y la división celular en el modelo L. sativa se puede proponer como una alternativa a las pruebas en animales para distinguir las variedades con concentraciones altas y bajas de éster de forbol, contribuyendo así a la detección de toxicidad en variedades utilizadas en programas de mejoramiento genético.


Assuntos
Ésteres de Forbol/toxicidade , Testes de Toxicidade , Germinação , Jatropha/química , Biocombustíveis
5.
J Agric Food Chem ; 66(11): 2510-2522, 2018 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-29498277

RESUMO

Jatropha curcas is an important oilseed plant, with considerable potential in the development of biodiesel. Although Jatropha seed cake, the byproduct of oil extraction, is a residue rich in nitrogen, phosphorus, potassium, and carbon, with high protein content suitable for application in animal feed, the presence of toxic phorbol esters limits its application in feed supplements and fertilizers. This review summarizes the current methods available for detoxification of this residue, based upon chemical, physical, biological, or combined processes. The advantages and disadvantages of each process are discussed, and future directions involving genomic and proteomic approaches for advancing our understanding of biodegradation processes involving microorganisms are highlighted.


Assuntos
Biotecnologia/métodos , Jatropha/química , Ésteres de Forbol/isolamento & purificação , Ração Animal/análise , Fertilizantes/análise , Jatropha/toxicidade , Ésteres de Forbol/toxicidade , Sementes/química , Sementes/toxicidade , Resíduos/análise
6.
Semin Cancer Biol ; 48: 36-52, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28571764

RESUMO

The AGC family of serine/threonine kinases (PKA, PKG, PKC) includes more than 60 members that are critical regulators of numerous cellular functions, including cell cycle and differentiation, morphogenesis, and cell survival and death. Mutation and/or dysregulation of AGC kinases can lead to malignant cell transformation and contribute to the pathogenesis of many human diseases. Members of one subgroup of AGC kinases, the protein kinase C (PKC), have been singled out as critical players in carcinogenesis, following their identification as the intracellular receptors of phorbol esters, which exhibit tumor-promoting activities. This observation attracted the attention of researchers worldwide and led to intense investigations on the role of PKC in cell transformation and the potential use of PKC as therapeutic drug targets in cancer diseases. Studies demonstrated that many cancers had altered expression and/or mutation of specific PKC genes. However, the causal relationships between the changes in PKC gene expression and/or mutation and the direct cause of cancer remain elusive. Independent studies in normal cells demonstrated that activation of PKC is essential for the induction of cell activation and proliferation, differentiation, motility, and survival. Based on these observations and the general assumption that PKC isoforms play a positive role in cell transformation and/or cancer progression, many PKC inhibitors have entered clinical trials but the numerous attempts to target PKC in cancer has so far yielded only very limited success. More recent studies demonstrated that PKC function as tumor suppressors, and suggested that future clinical efforts should focus on restoring, rather than inhibiting, PKC activity. The present manuscript provides some historical perspectives on the tumor promoting function of PKC, reviewing some of the observations linking PKC to cancer progression, and discusses the role of PKC in the pathogenesis of cancer diseases and its potential usage as a therapeutic target.


Assuntos
Genes Supressores de Tumor , Neoplasias/patologia , Proteína Quinase C/fisiologia , Inibidores de Proteínas Quinases/farmacologia , Trifosfato de Adenosina/metabolismo , Animais , Ligação Competitiva , Humanos , Terapia de Alvo Molecular , Neoplasias/enzimologia , Neoplasias/terapia , Oligonucleotídeos Antissenso/farmacologia , Ésteres de Forbol/toxicidade , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C/química , Proteína Quinase C beta/genética , Proteína Quinase C beta/metabolismo , Proteína Quinase C-delta/genética , Proteína Quinase C-delta/metabolismo , Inibidores de Proteínas Quinases/metabolismo
7.
Biochim Biophys Acta Gen Subj ; 1862(3): 414-426, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29154903

RESUMO

BACKGROUND: Mesenchymal-to-epithelial transition (MET) is associated with altered cell adhesion patterns. Independent studies showed that cellular adhesion regulates low-dose hyper-radiosensitivity (HRS), a phenomenon reported widely in tumour cells. Therefore, present study aimed to investigate whether MET and associated cellular adhesion alterations affect cellular radiosensitivity. METHODS: We established multiple stages of MET by in vitro transformation of NIH3T3 mouse embryonic fibroblasts. Nutritional deprivation followed by repetitive treatment cycles of 3-methylcholanthrene and phorbol-12-myristate-13-acetate with frequent isolation of foci established three progressive strains (NIH3T3.1, NIH3T3x3, NIH3T3x8x3) depicting MET, and one strain (NIH3T3x12) with partial reversion. Alterations in morphology, cell adhesion properties, expression/intracellular localization of cell adhesion proteins, microRNA expression and cellular radiosensitivity were studied in these stably transformed cell strains. RESULTS: All four transformants had increased proliferation rate, saturation density, bipolarity, E-cadherin expression; coupled with reduced cell size/spreading, pseudopodia/migration, and fibroblast marker protein and vimentin. The most aggressive trans-differentiated (phenotypically epithelial) cell strain, NIH3T3x8x3 acquired ~30% higher growth potential associated with more than two-fold reduction in cell size and migration. These phenotypic changes accompanied ~40% reduction in endogenous or radiation-induced connexin-43 expression/mitochondrial translocation. Incidentally, all three progressive strains displayed prominent HRS (αs/αr: 7.95-37.29) whereas parental (NIH3T3) and reverting (NIH3T3x12) strains lacked HRS and had distinct radiation-induced Cx43 translocation into mitochondria. CONCLUSION: Our study shows that trans-differentiating fibroblasts progressively acquiring epithelial features during MET process, display low-dose hyper-radiosensitivity associated with altered Cx43 behaviour. GENERAL SIGNIFICANCE: This study demonstrates that MET progression triggers low-dose hyper-radiosensitivity in trans-differentiating cells, which has significant therapeutic implications.


Assuntos
Transdiferenciação Celular/fisiologia , Conexina 43/metabolismo , Fibroblastos/efeitos dos fármacos , Metástase Neoplásica/fisiopatologia , Proteínas de Neoplasias/metabolismo , Tolerância a Radiação/fisiologia , Animais , Caderinas/biossíntese , Adesão Celular , Linhagem Celular Transformada , Movimento Celular , Tamanho Celular , Transformação Celular Neoplásica , Relação Dose-Resposta à Radiação , Fibroblastos/metabolismo , Fibroblastos/efeitos da radiação , Raios gama , Metilcolantreno/toxicidade , Camundongos , Mitocôndrias/metabolismo , Células NIH 3T3 , Ésteres de Forbol/toxicidade , Transporte Proteico
8.
Chem Biodivers ; 14(11)2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28795782

RESUMO

Chemical compositions, antioxidative, antimicrobial, anti-inflammatory, and cytotoxic activities of essential oils extracted from four common Curcuma species (Curcuma longa, Curcuma phaeocaulis, Curcuma wenyujin, and Curcuma kwangsiensis) rhizomes in P. R. China are comparatively studied. In total, 47, 49, 35, and 30 compounds are identified in C. longa, C. phaeocaulis, C. wenyujin, and C. kwangsiensis essential oils by GC/MS, and their richest compounds are ar-turmerone (21.67%), elemenone (19.41%), curdione (40.23%) and (36.47%), respectively. Moreover, C. kwangsiensis essential oils display the strongest DPPH (2,2-diphenyl-1-picrylhydrazyl) radical-scavenging activity (IC50 , 3.47 µg/ml), much higher than ascorbic acid (6.50 µg/ml). C. phaeocaulis oils show the best antibacterial activities against Escherichia coli (MIC, 235.54 µg/ml), Pseudomonas aeruginosa (391.31 µg/ml) and Staphylococcus aureus (378.36 µg/ml), while C. wenyujin and C. kwangsiensis oils show optimum activities against Candida albicans (208.61 µg/ml) and Saccharomyces cerevisiae (193.27 µg/ml), respectively. C. phaeocaulis (IC50 , 4.63 µg/ml) and C. longa essential oils (73.05 µg/ml) have the best cytotoxicity against LNCaP and HepG2, respectively. C. kwangsiensis oils also exhibit the strongest anti-inflammatory activities by remarkably down-regulating expression of COX-2 and TNF-α. Therefore, due to their different chemical compositions and bioactivities, traditional Chinese Curcuma herbs should be differentially served as natural additives for food, pharmaceutical, and cosmetic.


Assuntos
Curcuma/química , Óleos Voláteis/química , Animais , Anti-Infecciosos/análise , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Anti-Inflamatórios/análise , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Antioxidantes/análise , Antioxidantes/química , Candida albicans/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Curcuma/metabolismo , Ciclo-Oxigenase 2/metabolismo , Regulação para Baixo/efeitos dos fármacos , Edema/induzido quimicamente , Edema/metabolismo , Edema/prevenção & controle , Cromatografia Gasosa-Espectrometria de Massas , Células Hep G2 , Humanos , Camundongos , Óleos Voláteis/análise , Ésteres de Forbol/toxicidade , Saccharomyces cerevisiae/efeitos dos fármacos , Pele/efeitos dos fármacos , Pele/metabolismo , Pele/patologia , Staphylococcus aureus/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo
9.
BMC Complement Altern Med ; 16(1): 422, 2016 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-27784308

RESUMO

BACKGROUND: Bursera copallifera (Burseraceae) releases a resin known as "copal ancho" which has been used, since pre-Colombian times, as ceremonially burned incense and to treat tooth ache, tumors, arthritis, cold, cough, and various inflammatory conditions; however, its anti-inflammatory potential is poorly studied. The aim of the present study was to isolate, quantify, and to investigate the anti-inflammatory activity of triterpene compounds isolated from the copal resin of B. copallifera. METHODS: The constituents present in the total resin of B. copallifera were obtained by successive chromatographic procedures, and quantitative analysis was performed by High Performance Liquid Chromatography (HPLC). Anti-inflammatory effects of the isolated triterpenes were investigated to determine their inhibitory effects on phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced edema in mice, viability and nitric oxide (NO) production inhibition on lipopolysaccharide (LPS)-activated RAW 264.7 macrophages, and inhibition of cyclooxygenase (COX)-1, COX-2 and secretory Phospholipase A2 (sPLA2) activities in vitro. RESULTS: Quantitative phytochemical analysis of the copal resin showed the presence of six pentacyclic triterpenes of which, 3-epilupeol (59.75 % yield) and α-amyrin (21.1 % yield) are the most abundant. Among the isolated triterpenes, 3-epilupeol formiate (Inhibitory Concentration 50 % (IC50) = 0.96 µmol), α.amyrin acetate (IC50 = 1.17 µmol), lupenone (IC50 = 1.05 µmol), and 3-epilupeol (IC50 = 0.83 µmol) showed marked inhibition of the edema induced by TPA in mice. α-amyrin acetate and 3-epilupeol acetate, at 70 µM, also inhibited the activity of COX-2 by 62.85 and 73.28 % respectively, while α-amyrin and 3-epilupeol were the best inhibitors of the production of NO in LPS-activated RAW 264.7 cells with IC50 values of 15.5 and 8.98 µM respectively, and did not affected its viability. All compounds moderately inhibited the activity of PLA2. CONCLUSIONS: This work supports the folk use of B. copallifera and provides the basis for future investigations about the therapeutic use of this resin in treating inflammation.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Bursera/química , Triterpenos Pentacíclicos/farmacologia , Resinas Vegetais/farmacologia , Animais , Anti-Inflamatórios/química , Antioxidantes/química , Sobrevivência Celular/efeitos dos fármacos , Edema/induzido quimicamente , Edema/metabolismo , Inflamação , Masculino , Camundongos , Óxido Nítrico/metabolismo , Triterpenos Pentacíclicos/química , Ésteres de Forbol/toxicidade , Células RAW 264.7 , Resinas Vegetais/química
10.
Carcinogenesis ; 37(10): 1014-25, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27538837

RESUMO

The rising incidence of human papillomavirus (HPV)-associated malignancies, especially for oropharyngeal cancers, has highlighted the urgent need to understand how the interplay between high-risk HPV oncogenes and carcinogenic exposure results in squamous cell carcinoma (SCC) development. Here, we describe an inducible mouse model expressing high risk HPV-16 E6/E7 oncoproteins in adults, bypassing the impact of these viral genes during development. HPV-16 E6/E7 genes were targeted to the basal squamous epithelia in transgenic mice using a doxycycline inducible cytokeratin 5 promoter (cK5-rtTA) system. After doxycycline induction, both E6 and E7 were highly expressed, resulting in rapid epidermal hyperplasia with a remarkable expansion of the proliferative cell compartment to the suprabasal layers. Surprisingly, in spite of the massive growth of epithelial cells and their stem cell progenitors, HPV-E6/E7 expression was not sufficient to trigger mTOR activation, a key oncogenic driver in HPV-associated malignancies, and malignant progression to SCC. However, these mice develop SCC rapidly after a single exposure to a skin carcinogen, DMBA, which was increased by the prolonged exposure to a tumor promoter, 12-O-tetradecanoylphorbol-13-acetate (TPA). Thus, only few oncogenic hits may be sufficient to induce cancer in E6/E7 expressing cells. All HPV-E6/E7 expressing SCC lesions exhibited increased mTOR activation. Remarkably, rapamycin, an mTOR inhibitor, abolished tumor development when administered to HPV-E6/E7 mice prior to DMBA exposure. Our findings revealed that mTOR inhibition protects HPV-E6/E7 expressing tissues form SCC development upon carcinogen exposure, thus supporting the potential clinical use of mTOR inhibitors as a molecular targeted approach for prevention of HPV-associated malignancies.


Assuntos
Carcinógenos/toxicidade , Carcinoma de Células Escamosas/genética , Neoplasias Orofaríngeas/genética , Infecções por Papillomavirus/genética , Serina-Treonina Quinases TOR/biossíntese , 9,10-Dimetil-1,2-benzantraceno/toxicidade , Animais , Carcinoma de Células Escamosas/induzido quimicamente , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/virologia , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Papillomavirus Humano 16/genética , Papillomavirus Humano 16/patogenicidade , Humanos , Camundongos , Proteínas Oncogênicas Virais/genética , Neoplasias Orofaríngeas/induzido quimicamente , Neoplasias Orofaríngeas/tratamento farmacológico , Neoplasias Orofaríngeas/virologia , Proteínas E7 de Papillomavirus/genética , Infecções por Papillomavirus/patologia , Infecções por Papillomavirus/virologia , Ésteres de Forbol/toxicidade , Proteínas Repressoras/genética , Sirolimo/administração & dosagem , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/genética
11.
PLoS One ; 11(8): e0160939, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27509024

RESUMO

Exercise has been previously reported to lower cancer risk through reducing circulating IGF-1 and IGF-1-dependent signaling in a mouse skin cancer model. This study aims to investigate the underlying mechanisms by which exercise may down-regulate the IGF-1 pathway via p53 and p53-related regulators in the skin epidermis. Female SENCAR mice were pair-fed an AIN-93 diet with or without 10-week treadmill exercise at 20 m/min, 60 min/day and 5 days/week. Animals were topically treated with TPA 2 hours before sacrifice and the target proteins in the epidermis were analyzed by both immunohistochemistry and Western blot. Under TPA or vehicle treatment, MDM2 expression was significantly reduced in exercised mice when compared with sedentary control. Meanwhile, p53 was significantly elevated. In addition, p53-transcriptioned proteins, i.e., p21, IGFBP-3, and PTEN, increased in response to exercise. There was a synergy effect between exercise and TPA on the decreased MDM2 and increased p53, but not p53-transcripted proteins. Taken together, exercise appeared to activate p53, resulting in enhanced expression of p21, IGFBP-3, and PTEN that might induce a negative regulation of IGF-1 pathway and thus contribute to the observed cancer prevention by exercise in this skin cancer model.


Assuntos
Epiderme/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Condicionamento Físico Animal , Neoplasias Cutâneas/prevenção & controle , Proteína Supressora de Tumor p53/metabolismo , Animais , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Modelos Animais de Doenças , Feminino , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Camundongos Endogâmicos SENCAR , PTEN Fosfo-Hidrolase/metabolismo , Ésteres de Forbol/toxicidade , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Neoplasias Cutâneas/induzido quimicamente , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia
12.
PLoS One ; 11(6): e0157038, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27281340

RESUMO

The biggest challenge for jatropha breeding is to identify superior genotypes that present high seed yield and seed oil content with reduced toxicity levels. Therefore, the objective of this study was to estimate genetic parameters for three important traits (weight of 100 seed, oil seed content, and phorbol ester concentration), and to select superior genotypes to be used as progenitors in jatropha breeding. Additionally, the genotypic values and the genetic parameters estimated under the Bayesian multi-trait approach were used to evaluate different selection indices scenarios of 179 half-sib families. Three different scenarios and economic weights were considered. It was possible to simultaneously reduce toxicity and increase seed oil content and weight of 100 seed by using index selection based on genotypic value estimated by the Bayesian multi-trait approach. Indeed, we identified two families that present these characteristics by evaluating genetic diversity using the Ward clustering method, which suggested nine homogenous clusters. Future researches must integrate the Bayesian multi-trait methods with realized relationship matrix, aiming to build accurate selection indices models.


Assuntos
Jatropha/genética , Ésteres de Forbol/metabolismo , Óleos de Plantas/química , Característica Quantitativa Herdável , Sementes/genética , Teorema de Bayes , Variação Genética , Jatropha/crescimento & desenvolvimento , Fenótipo , Ésteres de Forbol/toxicidade , Sementes/crescimento & desenvolvimento
13.
J Neuroinflammation ; 13(1): 102, 2016 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-27160148

RESUMO

BACKGROUND: The relationship between the brain and the immune system has become increasingly topical as, although it is immune-specialised, the CNS is not free from the influences of the immune system. Recent data indicate that peripheral immune stimulation can significantly affect the CNS. But the mechanisms underpinning this relationship remain unclear. The standard approach to understanding this relationship has relied on systemic immune activation using bacterial components, finding that immune mediators, such as cytokines, can have a significant effect on brain function and behaviour. More rarely have studies used disease models that are representative of human disorders. METHODS: Here we use a well-characterised animal model of psoriasis-like skin inflammation-imiquimod-to investigate the effects of tissue-specific peripheral inflammation on the brain. We used full genome array, flow cytometry analysis of immune cell infiltration, doublecortin staining for neural precursor cells and a behavioural read-out exploiting natural burrowing behaviour. RESULTS: We found that a number of genes are upregulated in the brain following treatment, amongst which is a subset of inflammatory chemokines (CCL3, CCL5, CCL9, CXCL10, CXCL13, CXCL16 and CCR5). Strikingly, this model induced the infiltration of a number of immune cell subsets into the brain parenchyma, including T cells, NK cells and myeloid cells, along with a reduction in neurogenesis and a suppression of burrowing activity. CONCLUSIONS: These findings demonstrate that cutaneous, peripheral immune stimulation is associated with significant leukocyte infiltration into the brain and suggest that chemokines may be amongst the key mediators driving this response.


Assuntos
Encéfalo/patologia , Quimiocinas/metabolismo , Quimiotaxia de Leucócito/fisiologia , Dermatite/patologia , Leucócitos/patologia , Glicoproteínas de Membrana/metabolismo , Receptor 7 Toll-Like/metabolismo , Aminoquinolinas/toxicidade , Animais , Encéfalo/metabolismo , Complexo CD3/metabolismo , Quimiocinas/genética , Quimiotaxia de Leucócito/efeitos dos fármacos , Dermatite/etiologia , Modelos Animais de Doenças , Proteínas do Domínio Duplacortina , Feminino , Citometria de Fluxo , Perfilação da Expressão Gênica , Imiquimode , Indutores de Interferon/toxicidade , Camundongos , Proteínas Associadas aos Microtúbulos/metabolismo , Neuropeptídeos/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Ésteres de Forbol/toxicidade , RNA Mensageiro/metabolismo
14.
Nat Prod Res ; 30(16): 1885-9, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26395173

RESUMO

The hexanic, ethyl acetate and methanolic extracts from branches of Stenocereus stellatus were tested in both the 12-O-tetradecanoylphorbol-13-acetate (TPA) - induced ear oedema model and antimicrobial activity assay. The % of oedema inhibition, the Minimum Inhibitory Concentration (MIC), as well as the polyphenolic and flavonoid content were determined. Also, extracts were analysed by gas chromatography-mass spectrometry (GC-MS). In TPA model, the three extracts showed moderate oedema inhibition. In the antimicrobial activity assay, methanolic extract shows better MIC against all strains. The lowest MICs were for Candida albicans (31 µg/mL) and Rhizopus sp. (15 µg/mL). Also, 50.78 mg eq. of gallic acid/g extract of polyphenol and 115.12 mg eq. of catequine/g extract of flavonoids content were founded in ethyl acetate extract. In the chromatographic analysis, ß-sitosterol, ß-amyrine, betulin and some other molecules were identified. The results show that S. stellatus possess antimicrobial activities against some fungus species.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Cactaceae/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Polifenóis/análise , Animais , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Anti-Inflamatórios não Esteroides/química , Antioxidantes/química , Cactaceae/metabolismo , Candida albicans/efeitos dos fármacos , Modelos Animais de Doenças , Edema/induzido quimicamente , Edema/tratamento farmacológico , Flavonoides/análise , Cromatografia Gasosa-Espectrometria de Massas , Masculino , Testes de Sensibilidade Microbiana , Ésteres de Forbol/toxicidade , Rhizopus/efeitos dos fármacos , Metabolismo Secundário , Sitosteroides/análise
15.
Biomed Res Int ; 2015: 318306, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25918710

RESUMO

Perinatal infections have a negative impact on brain development. However, the underlying mechanisms leading to neurological impairment are not completely understood and reliable models of inflammation are urgently needed. Using phorbol-myristate-acetate as an activator of inflammation, we investigated the effect on the developing rodent brain. Neonatal rats and mice deficient in IL-18 or IRAK-4 were exposed to PMA. Brains were assessed for regulation of pro- and anti-inflammatory cytokines and cell death 24 hrs, 7 and 14 days after treatment. PMA induced an inflammatory response and caused widespread neurodegeneration in the brains of 3- and 7-day-old rats. In contrast, 14-day-old rats were resistant to the neurotoxic effect of PMA. Histological evaluation at the age of 14 and 21 days revealed a destruction of the cortical microstructure with decreased numerical density of neuronal cells. Mice deficient in IL-18 or IRAK-4 were protected against PMA induced brain injury. PMA treatment during a vulnerable period can alter brain development. IL-18 and IRAK-4 appear to be important for the development of PMA induced injury.


Assuntos
Lesões Encefálicas/genética , Encéfalo/crescimento & desenvolvimento , Inflamação/fisiopatologia , Quinases Associadas a Receptores de Interleucina-1/genética , Interleucina-18/genética , Animais , Encéfalo/efeitos dos fármacos , Lesões Encefálicas/induzido quimicamente , Lesões Encefálicas/fisiopatologia , Feminino , Inflamação/induzido quimicamente , Inflamação/metabolismo , Quinases Associadas a Receptores de Interleucina-1/deficiência , Interleucina-18/deficiência , Camundongos , Ésteres de Forbol/toxicidade , Gravidez , Ratos
16.
Int J Mol Sci ; 15(2): 2274-88, 2014 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-24504029

RESUMO

The presence of phorbol esters (PEs) with toxic properties limits the use of Jatropha curcas kernel in the animal feed industry. Therefore, suitable methods to detoxify PEs have to be developed to render the material safe as a feed ingredient. In the present study, the biological treatment of the extracted PEs-rich fraction with non-pathogenic fungi (Trichoderma harzianum JQ350879.1, T. harzianum JQ517493.1, Paecilomyces sinensis JQ350881.1, Cladosporium cladosporioides JQ517491.1, Fusarium chlamydosporum JQ350882.1, F. chlamydosporum JQ517492.1 and F. chlamydosporum JQ350880.1) was conducted by fermentation in broth cultures. The PEs were detected by liquid chromatography-diode array detector-electrospray ionization mass spectrometry (LC-DAD-ESIMS) and quantitatively monitored by HPLC using phorbol-12-myristate 13-acetate as the standard. At day 30 of incubation, two T. harzianum spp., P. sinensis and C. cladosporioides significantly (p < 0.05) removed PEs with percentage losses of 96.9%-99.7%, while F. chlamydosporum strains showed percentage losses of 88.9%-92.2%. All fungal strains could utilize the PEs-rich fraction for growth. In the cytotoxicity assay, cell viabilities of Chang liver and NIH 3T3 fibroblast cell lines were less than 1% with the untreated PEs-rich fraction, but 84.3%-96.5% with the fungal treated PEs-rich fraction. There was no inhibition on cell viability for normal fungal growth supernatants. To conclude, Trichoderma spp., Paecilomyces sp. and Cladosporium sp. are potential microbes for the detoxification of PEs.


Assuntos
Biotransformação , Endófitos/metabolismo , Jatropha/química , Ésteres de Forbol/química , Trichoderma/metabolismo , Ração Animal , Animais , Carbono/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Fracionamento Químico , Meios de Cultura , Fermentação , Humanos , Ésteres de Forbol/toxicidade
17.
J Biol Chem ; 288(51): 36473-83, 2013 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-24194523

RESUMO

The inflammatory response is normally limited by mechanisms regulating its resolution. In the absence of resolution, inflammatory pathologies can emerge, resulting in substantial morbidity and mortality. We have been studying the D6 chemokine scavenging receptor, which played an indispensable role in the resolution phase of inflammatory responses and does so by facilitating removal of inflammatory CC chemokines. In D6-deficient mice, otherwise innocuous cutaneous inflammatory stimuli induce a grossly exaggerated inflammatory response that bears many similarities to human psoriasis. In the present study, we have used transcriptomic approaches to define the molecular make up of this response. The data presented highlight potential roles for a number of cytokines in initiating and maintaining the psoriasis-like pathology. Most compellingly, we provide data indicating a key role for the type I interferon pathway in the emergence of this pathology. Neutralizing antibodies to type I interferons are able to ameliorate the psoriasis-like pathology, confirming a role in its development. Comparison of transcriptional data generated from this mouse model with equivalent data obtained from human psoriasis further demonstrates the strong similarities between the experimental and clinical systems. As such, the transcriptional data obtained in this preclinical model provide insights into the cytokine network active in exaggerated inflammatory responses and offer an excellent tool to evaluate the efficacy of compounds designed to therapeutically interfere with inflammatory processes.


Assuntos
Interferon Tipo I/metabolismo , Psoríase/imunologia , Receptores CCR10/genética , Animais , Feminino , Inflamação/genética , Inflamação/metabolismo , Inflamação/patologia , Interferon Tipo I/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Análise de Sequência com Séries de Oligonucleotídeos , Ésteres de Forbol/toxicidade , Psoríase/induzido quimicamente , Psoríase/genética , Psoríase/patologia , Transcrição Gênica , Receptor D6 de Quimiocina
18.
J Environ Sci Health B ; 48(11): 974-82, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23998310

RESUMO

Jatropha seed cake contains high amounts of protein and other nutrients, however it has a drawback due to toxic compounds. The aim of this study was to investigate the methods applied to detoxify the main toxin, phorbol esters in jatropha seed cake, to a safe and acceptable level by maintaining the nutritional values. Phorbol esters are tetracyclic diterpenoids-polycyclic compounds that are known as tumor promoters and hence exhibited the toxicity within a broad range of species. Mismanagement of the jatropha waste from jatropha oil industries would lead to contamination of the environment, affecting living organisms and human health through the food chain, so several methods were tested for reducing the toxicity of the seed cake. The results from this investigation showed that heat treatments at either 120°C or 220°C for 1 hour and then mixing with adsorbing bentonite (10%), nanoparticles of zinc oxide (100 µg/g) plus NaHCO3 at 4%, followed by a 4-week incubation period yielded the best final product. The remaining phorbol esters concentration (0.05-0.04 mg/g) from this treatment was less than that reported for the nontoxic jatropha varieties (0.11-0.27 mg/g). Nutritional values of the seed cake after treatment remained at the same levels found in the control group and these values were crude protein (20.47-21.40 + 0.17-0.25%), crude lipid (14.27-14.68 + 0.13-0.14%) and crude fiber (27.33-29.67 + 0.58%). A cytotoxicity test conducted using L929 and normal human dermal fibroblast cell lines confirmed that most of the toxic compounds, especially phorbol esters, were shown as completely eliminated. The results suggested that the detoxification of phorbol esters residues in the jatropha seed cake was possible while it also retained nutritional values. Therefore, the methods to detoxify phorbol esters are necessary to minimize the toxicity of jatropha seed cake. Further, it is essential to reduce the possible environmental impacts that may be generated throughout the jatropha waste-handling process. However additional tests such as digestibility as well as acceptability of the treated jatropha seed cake should be conducted using both in vivo and in vitro studies before recommending the jatropha seed cake as a source of renewable animal feed and other value-added products.


Assuntos
Ração Animal/toxicidade , Jatropha/química , Valor Nutritivo , Ésteres de Forbol/toxicidade , Adsorção , Ração Animal/análise , Bentonita/química , Linhagem Celular , Temperatura Alta , Humanos , Nanopartículas/química , Ésteres de Forbol/análise , Sementes/química , Bicarbonato de Sódio/química , Óxido de Zinco/química
19.
J Neuroimmunol ; 262(1-2): 62-5, 2013 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-23870536

RESUMO

Melatonin has documented cytoprotective effects on a wide variety of immune cells. The mechanism of action on mast cells (RBL-2H3) still remains in the dark. We found that melatonin significantly attenuated phorbol 12-myristate 13-acetate plus calcium ionophore A23187 (PMACI)-induced cytotoxicity in a concentration and time-dependent manner. It appears that the effect of melatonin on mast cells is two-fold: dependent (MT1 and MT2) and independent membrane receptors. In conclusion, melatonin treatment reduced the cytotoxicity, mediated by PMACI, and could provide a useful therapeutic option in processes where an excessive activation of mast cells occurs.


Assuntos
Antioxidantes/farmacologia , Calcimicina/toxicidade , Mastócitos/efeitos dos fármacos , Melatonina/farmacologia , Animais , Antioxidantes/administração & dosagem , Ionóforos de Cálcio/toxicidade , Carcinógenos/toxicidade , Linhagem Celular Tumoral , Citotoxicidade Imunológica , Regulação para Baixo/imunologia , Melatonina/administração & dosagem , Ésteres de Forbol/toxicidade , Ratos , Fatores de Tempo
20.
Free Radic Biol Med ; 63: 432-45, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23770196

RESUMO

Sirtuin 2 (SIRT2), a member of the sirtuin family of proteins, plays an important role in cell survival. However, the biological function of SIRT2 protein is unclear with respect to inflammation and oxidative stress. In this study, we examined the protective effects of SIRT2 on inflammation and oxidative stress-induced cell damage using a cell permeative PEP-1-SIRT2 protein. Purified PEP-1-SIRT2 was transduced into RAW 264.7 cells in a time- and dose-dependent manner and protected against lipopolysaccharide- and hydrogen peroxide (H2O2)-induced cell death and cytotoxicity. Also, transduced PEP-1-SIRT2 significantly inhibited the expression of cytokines as well as the activation of NF-κB and mitogen-activated protein kinases (MAPKs). In addition, PEP-1-SIRT2 decreased cellular levels of reactive oxygen species (ROS) and of cleaved caspase-3, whereas it elevated the expression of antioxidant enzymes such as MnSOD, catalase, and glutathione peroxidase. Furthermore, topical application of PEP-1-SIRT2 to 12-O-tetradecanoylphorbol 13-acetate-treated mouse ears markedly inhibited expression levels of COX-2 and proinflammatory cytokines as well as the activation of NF-κB and MAPKs. These results demonstrate that PEP-1-SIRT2 inhibits inflammation and oxidative stress by reducing the levels of expression of cytokines and ROS, suggesting that PEP-1-SIRT2 may be a potential therapeutic agent for various disorders related to ROS, including skin inflammation.


Assuntos
Inflamação/metabolismo , Estresse Oxidativo , Peptídeos/metabolismo , Sirtuína 2/metabolismo , Animais , Antioxidantes/metabolismo , Morte Celular/efeitos dos fármacos , Morte Celular/genética , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Peróxido de Hidrogênio/toxicidade , Inflamação/tratamento farmacológico , Inflamação/patologia , Lipopolissacarídeos/toxicidade , Macrófagos/efeitos dos fármacos , Macrófagos/enzimologia , Macrófagos/metabolismo , Camundongos , Peptídeos/administração & dosagem , Peptídeos/síntese química , Peptídeos/genética , Ésteres de Forbol/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Sirtuína 2/administração & dosagem , Sirtuína 2/genética , Pele/efeitos dos fármacos , Pele/crescimento & desenvolvimento
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...