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3.
Eur Rev Med Pharmacol Sci ; 25(24): 7765-7776, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34982438

RESUMO

OBJECTIVE: Atherosclerosis is a chronic inflammatory disease promoted by pro-inflammatory cytokines produced by NOD-, LRR- and pyrin domain-containing protein 3 (NLRP 3) inflammasome. Colchicine is an anti-inflammatory agent that inhibits inflammasome's action and stabilizes atherosclerotic lesions. N-acetylcysteine (NAC) reduces low-density lipoprotein (LDL) oxidation, metalloproteinase levels, and foam cell count and volume. Fenofibrate also has antioxidant, anti-inflammatory, and anticoagulant properties while also having a beneficial effect on the vasomotor function of the endothelium. The purpose of this study is to investigate the effect of per os colchicine administration in combination with fenofibrate and NAC on triglyceride levels and the development of atherosclerotic lesions in cholesterol-fed rabbits. MATERIALS AND METHODS: Twenty-eight male, 2 months old New Zealand White rabbits were separated into four groups and were fed with different types of diet for 7 weeks: standard, cholesterol 1% w/w, cholesterol 1% w/w plus colchicine 2 mg/kg body weight plus 250 mg/kg body weight/day fenofibrate, and cholesterol 1% w/w plus colchicine 2 mg/kg body weight plus 15 mg/kg body weight/day NAC. Blood samples were drawn from all animals. Lipid profiles were assessed, and interleukin 6 (IL-6) measurements were performed using an enzyme-linked immunosorbent assay (ELISA) kit. Histologic examination was performed on aorta specimens stained with eosin and hematoxylin. Aortic intimal thickness was evaluated using image analysis. RESULTS: Colchicine administration in combination with fenofibrate or NAC statistically significantly reduced the extent of atherosclerotic lesions in aortic preparations. Co-administration of colchicine with NAC has a stronger anti-atherogenic effect than the colchicine plus fenofibrate regimen. Triglerycide levels were decreased in the colchicine plus fenofibrate group and the colchicine plus NAC group at the end of the experiment (p < 0.05), whereas the Cholesterol group had increased levels. A favorable significant lower concentration of IL-6 was detected in the colchicine plus NAC group vs. the other groups. CONCLUSIONS: In an experimental rabbit model, it appears that colchicine statistically significantly reduces the development of atherosclerosis of the aorta, especially in combination with NAC. Colchicine, as an NLRP3 inflammasome inhibitor, and NAC, as an agent that directly targets IL-6 signaling, can reduce the inflammatory risk. Fenofibrate enhances the attenuating role of colchicine on triglyceride levels. Clinical studies should investigate whether similar effects can be observed in humans.


Assuntos
Acetilcisteína/administração & dosagem , Anti-Inflamatórios/administração & dosagem , Aterosclerose/tratamento farmacológico , Colchicina/administração & dosagem , Fenofibrato/administração & dosagem , Hipolipemiantes/administração & dosagem , Administração Oral , Animais , Aorta/efeitos dos fármacos , Aorta/patologia , Aterosclerose/sangue , Aterosclerose/patologia , Proteína C-Reativa/análise , Colesterol/administração & dosagem , Quimioterapia Combinada , Interleucina-6/antagonistas & inibidores , Interleucina-6/sangue , Masculino , Proteína 3 que Contém Domínio de Pirina da Família NLR/antagonistas & inibidores , Coelhos , Triglicerídeos/sangue
5.
Oncogene ; 39(10): 2224-2226, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31819168

RESUMO

After publication of this Article the authors noticed errors in several figures. In Fig. 2b the Gapdh panels are incorrect. The lysates are identical to those used in Fig. 1b, therefore the Gapdh panels should be the same in both figures. In Fig. 3b the Gapdh panels for Ad-Fhit-wt and Ad-Fhit-Y114F are incorrect and have been replaced with scans from original films. In Fig. 4A the Gapdh panels are incorrect. The lysates are identical to those used in Fig. 3b, therefore the Gapdh panels should be the same in both figures. In Fig. 4Bb the Gapdh panels for Fhit siRNA were incorrect and have been replaced with scans from original films. All resupplied figures are provided below. In Fig. 5C several panels are incorrect. The Authors were unable to locate the original films for all of these panels so Fig. 5c has been deleted. The scientific conclusions of this paper have not been affected.

6.
Eur Rev Med Pharmacol Sci ; 23(1): 303-311, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30657571

RESUMO

OBJECTIVE: Cardiac allograft vasculopathy (CAV) is a leading cause of mortality in heart transplantation patients. Despite optimal immunosuppression therapy, the rate of CAV post-transplantation remains high. In this review, we gathered all recent studies as well as experimental evidence focusing on the prevention and treatment strategies regarding CAV after heart transplantation. MATERIALS AND METHODS: A complete literature survey was performed using the PubMed database search to gather available information regarding prevention and treatment strategies of CAV after heart transplantation. RESULTS: Several non-immune and immune factors have been linked to CAV such as ischemic reperfusion injury, metabolic disorders, cytomegalovirus infection, coronary endothelial dysfunction, injury and inflammation respectively. Serial coronary angiography combined with intravascular ultrasound is currently the method of choice for detecting early disease. Biomarkers and noninvasive imaging can also assist in the early identification of CAV. Treatment strategies such as mammalian target of rapamycin inhibitors proceed to grow, but prevention remains the objective. CONCLUSIONS: Early detection is the key to therapy management. It enables early identification and diagnosis of patients with CAV, who would gain the most from prompt treatment. Further investigation is needed to elucidate the multifactorial pathophysiological process of CAV, develop detection methods and find treatments that prevent or slow disease progression.


Assuntos
Angiografia Coronária/métodos , Doença da Artéria Coronariana/prevenção & controle , Transplante de Coração/efeitos adversos , Complicações Pós-Operatórias/prevenção & controle , Aloenxertos/irrigação sanguínea , Aloenxertos/diagnóstico por imagem , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/etiologia , Vasos Coronários/diagnóstico por imagem , Coração/diagnóstico por imagem , Humanos , Revascularização Miocárdica/métodos , Inibidores da Agregação Plaquetária/uso terapêutico , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/etiologia , Reoperação
7.
Neurogastroenterol Motil ; 28(3): 410-22, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26670691

RESUMO

BACKGROUND: Irritable bowel syndrome (IBS) is a stress-sensitive disorder. Environmental factors including stress can trigger epigenetic changes, which have not been well-studied in IBS. We performed a pilot study investigating genome-wide DNA methylation of IBS patients and healthy controls (HCs) to identify potential epigenetic markers and associated pathways. Additionally, we investigated relationships of epigenetic changes in selected genes with clinical traits. METHODS: Twenty-seven IBS patients (59% women; 10 IBS-diarrhea, 8 IBS-constipation, 9 IBS-mixed) and 23 age- and sex-matched HCs were examined. DNA methylation from peripheral blood mononuclear cells (PBMCs) was measured using HM450 BeadChip, and representative methylation differences were confirmed by bisulphite sequencing. Gene expression was measured using quantitative PCR. Gastrointestinal (GI) and non-GI symptoms were measured using validated questionnaires. Associations were tested using non-parametric methods. KEY RESULTS: Genome-wide DNA methylation profiling of IBS patients compared with HCs identified 133 differentially methylated positions (DMPs) (mean difference ≥10%; p < 0.05). These genes were associated with gene ontology terms including glutathione metabolism related to oxidative stress and neuropeptide hormone activity. Validation by sequencing confirmed differential methylation of subcommissural organ (SCO)-Spondin (SSPO), glutathione-S-transferases mu 5 (GSTM5), and tubulin polymerization promoting protein genes. Methylation of two promoter CpGs in GSTM5 was associated with epigenetic silencing. Epigenetic changes in SSPO gene were positively correlated with hospital anxiety and depression scores in IBS patients (r > 0.4 and false discovery rate <0.05). CONCLUSIONS & INFERENCES: This study is the first to comprehensively explore the methylome of IBS patients. We identified DMPs in novel candidate genes which could provide new insights into disease mechanisms; however, these preliminary findings warrant confirmation in larger, independent studies.


Assuntos
Metilação de DNA , Síndrome do Intestino Irritável/genética , Leucócitos Mononucleares/metabolismo , Estresse Fisiológico/genética , Adulto , Feminino , Estudo de Associação Genômica Ampla , Humanos , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Projetos Piloto , Reação em Cadeia da Polimerase
8.
Euro Surveill ; 19(16): 20782, 2014 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-24786258

RESUMO

On 18 April 2014, a case of Middle East Respiratory Syndrome coronavirus (MERS-CoV) infection was laboratory confirmed in Athens, Greece in a patient returning from Jeddah, Saudi Arabia. Main symptoms upon initial presentation were protracted fever and diarrhoea, during hospitalisation he developed bilateral pneumonia and his condition worsened. During 14 days prior to onset of illness, he had extensive contact with the healthcare environment in Jeddah. Contact tracing revealed 73 contacts, no secondary cases had occurred by 22 April.


Assuntos
Infecções por Coronavirus/diagnóstico , Coronavirus/isolamento & purificação , Pneumonia Viral/virologia , Infecções Respiratórias/diagnóstico , Viagem , Idoso , Busca de Comunicante , Coronavirus/genética , Infecções por Coronavirus/genética , Infecções por Coronavirus/virologia , Diarreia , Febre/etiologia , Grécia , Humanos , Masculino , Infecções Respiratórias/virologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Arábia Saudita , Síndrome , Resultado do Tratamento
9.
Euro Surveill ; 18(18): 20474, 2013 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-23725773

RESUMO

Greece has been rabies-free since 1987 with no human cases since 1970. During 2012 to 2013, rabies has re-emerged in wild and domestic animals in northern Greece. By end March 2013, rabies was diagnosed in 17 animals including 14 red foxes, two shepherd dogs and one cat; 104 subsequent human exposures required post-exposure prophylaxis according to the World Health Organization criteria. Human exposures occurred within 50 km radius of a confirmed rabies case in a wild or domestic animal, and most frequently stray dogs were involved.


Assuntos
Doenças do Gato/epidemiologia , Doenças do Cão/epidemiologia , Profilaxia Pós-Exposição , Vacina Antirrábica/administração & dosagem , Raiva/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Animais Domésticos , Animais Selvagens , Doenças do Gato/transmissão , Doenças do Gato/virologia , Gatos , Criança , Busca de Comunicante , Surtos de Doenças , Doenças do Cão/transmissão , Doenças do Cão/virologia , Cães , Feminino , Raposas/virologia , Grécia/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Raiva/etiologia , Raiva/transmissão , Raiva/veterinária , Vírus da Raiva/imunologia , Vírus da Raiva/isolamento & purificação , Adulto Jovem
10.
Oncogene ; 32(13): 1651-9, 2013 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-22614013

RESUMO

MicroRNAs (miRNAs) have been involved in the pathogenesis of different types of cancer; however, their function in pituitary tumorigenesis remains poorly understood. Cyclic-AMP-dependent protein kinase-defective pituitaries occasionally form aggressive growth-hormone (GH)-producing pituitary tumors in the background of hyperplasia caused by haploinsufficiency of the protein kinase's main regulatory subunit, PRKAR1A. The molecular basis for this development remains unknown. We have identified a 17-miRNA signature of pituitary tumors formed in the background of hyperplasia (caused in half of the cases by PRKAR1A-mutations). We selected two miRNAs on the basis of their functional screen analysis: inhibition of miR-26b expression and upregulation of miR-128 suppressed the colony formation ability and invasiveness of pituitary tumor cells. Furthermore, we identified that miR-26b and miR-128 affected pituitary tumor cell behavior through regulation of their direct targets, PTEN and BMI1, respectively. In addition, we found that miR-128 through BMI1 direct binding on the PTEN promoter affected PTEN expression levels and AKT activity in the pituitary tumor cells. Our in vivo data revealed that inhibition of miR-26b and overexpression of miR-128 could suppress pituitary GH3 tumor growth in xenografts. Taken together, we have identified a miRNA signature for GH-producing pituitary tumors and found that miR-26b and miR-128 regulate the activity of the PTEN-AKT pathway in these tumors. This is the first suggestion of the possible involvement of miRNAs regulating the PTEN-AKT pathway in GH-producing pituitary tumor formation in the context of hyperplasia or due to germline PRKAR1A defects. MiR-26b suppression and miR-128 upregulation could have therapeutic potential in GH-producing pituitary tumor patients.


Assuntos
Adenoma/patologia , Proliferação de Células , Adenoma Hipofisário Secretor de Hormônio do Crescimento/patologia , MicroRNAs/fisiologia , Proteína Oncogênica v-akt/fisiologia , PTEN Fosfo-Hidrolase/fisiologia , Adenoma/genética , Animais , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Corticotrofos/metabolismo , Corticotrofos/patologia , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/fisiologia , Adenoma Hipofisário Secretor de Hormônio do Crescimento/genética , Humanos , Camundongos , Camundongos Nus , MicroRNAs/genética , MicroRNAs/farmacologia , Análise de Sequência com Séries de Oligonucleotídeos , Proteína Oncogênica v-akt/genética , Proteína Oncogênica v-akt/metabolismo , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , Prolactinoma/genética , Prolactinoma/patologia , Ratos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Somatotrofos/efeitos dos fármacos , Somatotrofos/metabolismo , Somatotrofos/patologia
11.
Oncogene ; 31(23): 2862-75, 2012 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-21986943

RESUMO

In the present study we analyzed the regulation of the two isoforms of the RhoA-specific guanine nucleotide exchange factor Net1 by transforming growth factor-ß (TGF-ß) in keratinocytes. We report that short-term TGF-ß treatment selectively induced Net1 isoform2 (Net1A) but not Net1 isoform1. This led to upregulation of cytoplasmic Net1A protein levels that were necessary for TGF-ß-mediated RhoA activation. Smad signaling and the MAPK/ERK kinase (MEK)/extracellular signal-regulated kinase (ERK) pathway were involved in Net1A upregulation by TGF-ß. Interestingly, long-term TGF-ß treatment resulted in Net1 mRNA downregulation and Net1A protein degradation by the proteasome. Furthermore, we identified the microRNA miR-24 as a novel post-transcriptional regulator of Net1A expression. Silencing of Net1A resulted in disruption of E-cadherin- and zonula occludens-1 (ZO-1)-mediated junctions, as well as expression of the transcriptional repressor of E-cadherin, Slug and the mesenchymal markers N-cadherin, plasminogen activator inhibitor-1 (PAI-1) and fibronectin, indicating that late TGF-ß-induced downregulation of Net1A is involved in epithelial-to-mesenchymal transition (EMT). Finally, miR-24 was found to be implicated in the regulation of the EMT program in response to TGF-ß and was shown to be directly involved in the TGF-ß-induced breast cancer cell invasiveness through Net1A regulation. Our results emphasize the importance of Net1 isoform2 in the short- and long-term TGF-ß-mediated regulation of EMT.


Assuntos
Transição Epitelial-Mesenquimal , Regulação da Expressão Gênica , MicroRNAs/genética , Proteínas Oncogênicas/genética , Interferência de RNA , Fator de Crescimento Transformador beta/farmacologia , Proteína rhoA de Ligação ao GTP/metabolismo , Caderinas/metabolismo , Células Cultivadas , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Humanos , Queratinócitos/citologia , Queratinócitos/metabolismo , Rim/citologia , Rim/metabolismo , Neoplasias/metabolismo , Neoplasias/patologia , Proteínas Oncogênicas/metabolismo , Fosforilação , Isoformas de Proteínas , Proteólise , Transdução de Sinais
12.
Oncogene ; 31(33): 3818-25, 2012 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-22120719

RESUMO

The peroxisome proliferators-activated receptor (PPAR)γ pathway is involved in cancer, but it appears to have both tumor suppressor and oncogenic functions. In neuroblastoma cells, miR-27b targets the 3' untranslated region of PPARγ and inhibits its mRNA and protein expression. miR-27b overexpression or PPARγ inhibition blocks cell growth in vitro and tumor growth in mouse xenografts. PPARγ activates expression of the pH regulator NHE1, which is associated with tumor progression. Lastly, miR-27b through PPARγ regulates nuclear factor-κB activity and transcription of inflammatory target genes. Thus, in neuroblastoma, miR-27b functions as a tumor suppressor by inhibiting the tumor-promoting function of PPARγ, which triggers an increased inflammatory response. In contrast, in breast cancer cells, PPARγ inhibits NHE1 expression and the inflammatory response, and it functions as a tumor suppressor. We suggest that the ability of PPARγ to promote or suppress tumor formation is linked to cell type-specific differences in regulation of NHE1 and other target genes.


Assuntos
Proliferação de Células , Inflamação/prevenção & controle , MicroRNAs/fisiologia , Neuroblastoma/patologia , PPAR gama/fisiologia , Regiões 3' não Traduzidas/fisiologia , Animais , Proteínas de Transporte de Cátions/fisiologia , Linhagem Celular Tumoral , Progressão da Doença , Humanos , Camundongos , MicroRNAs/análise , Neuroblastoma/prevenção & controle , PPAR gama/antagonistas & inibidores , Trocador 1 de Sódio-Hidrogênio , Trocadores de Sódio-Hidrogênio/fisiologia
13.
Nutr Metab Cardiovasc Dis ; 20(10): 740-7, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19748252

RESUMO

BACKGROUND AND AIMS: Virgin olive oil polar lipid extract (OOPL) and olive pomace polar lipid extract (PPL) have similar antiatherosclerotic effects in cholesterol-fed rabbits. Our aim was to compare the effect of PPL with that of simvastatin on the progression of atherogenesis. METHODS AND RESULTS: Rabbits were fed an atherogenic diet for 6 weeks in order to develop dyslipidemia and atheromatous lesions. Following documentation of these events in random animals (group A, n=6), the remaining were fed for 3 weeks with: standard chow alone (group B, n=6), chow supplemented with PPL (group C, n=6), and chow supplemented with simvastatin (group D, n=6). Blood was collected at 0, 6 and 9 weeks, to determine plasma lipid levels, plasma PAF-AH activity, platelet aggregation (PAF-EC(50)), resistance of plasma to oxidation (RPO) and extent of atheromatous lesions in aortas. The atherogenic diet induced dyslipidemia and increased PAF-AH activity. Dyslipidemia and PAF-activity reduced more effectively in groups C and D. RPO decreased in group B only. PAF-EC(50) values decreased in group C only. Atherogenesis progression in group C was prevented to an extent indistinguishable from that in group D. PAF-AH activity was positively correlated, whereas RPO was negatively correlated with the extent of atheromatous lesions. CONCLUSION: PPL, as a dietary supplement, is equipotent to simvastatin in preventing the progression of atherogenesis.


Assuntos
Aterosclerose/prevenção & controle , Colesterol/sangue , Olea/química , Óleos de Plantas/farmacologia , Análise de Variância , Animais , Dieta Aterogênica , Suplementos Nutricionais , Modelos Animais de Doenças , Dislipidemias/metabolismo , Masculino , Azeite de Oliva , Agregação Plaquetária , Coelhos , Análise de Regressão , Sinvastatina/farmacologia
14.
Euro Surveill ; 14(21)2009 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-19480814

RESUMO

On 26 and 27 May, the Hellenic Centre for Disease Control and Prevention in Greece reported two confirmed cases of new influenza A(H1N1) virus infection in travellers returning from Scotland. The two cases had no apparent traceable links to an infectious source. Herein we report details of the two cases and potential public health implications.


Assuntos
Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/epidemiologia , Viagem , União Europeia , Grécia/epidemiologia , Humanos , Influenza Humana/fisiopatologia , Masculino , Escócia , Adulto Jovem
15.
Cytogenet Genome Res ; 118(2-4): 196-203, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18000371

RESUMO

FHIT, at a constitutively active chromosome fragile site, is often a target of chromosomal aberrations and deletion in a large fraction of human tumors. Inactivation of murine Fhit allelessignificantly increases susceptibility of mice to spontaneous and carcinogen-induced tumorigenesis. In this study, transgenic mice, carrying a human FHIT cDNA under control of the endogenous promoter, were produced to determine the effect of Fhit expression, from a nonfragile cDNA transgene outside the fragile region, on carcinogen-induced tumor susceptibility of wildtype and Fhit heterozygous mice. Mice received sufficient oral doses of N-nitrosomethybenzylamine (NMBA) to cause forestomach tumors in >80% of nontransgenic control mice. Although the level of expression of the FHIT transgene in the recombinant mouse strains was much lower than the level of endogenous Fhit expression, the tumor burden in NMBA-treated male transgenic mice was significantly reduced, while female transgenic mice were not protected. To determine if the difference in protection could be due to differences in epigenetic changes at the transgene loci in male versus female mice, we examined expression, hypermethylation and induced re-expression of FHIT transgenes in male and female mice or cells derived from them. The transgene was methylated in male and female mice and in cell lines established from male and female transgenic kidneys, the FHIT locus was both hypermethylated and deacetylated. It is likely that the FHIT transgene is more tightly silenced in female transgenic mice, leading to a lack of protection from tumor induction.


Assuntos
Hidrolases Anidrido Ácido/genética , Predisposição Genética para Doença , Proteínas de Neoplasias/genética , Neoplasias Experimentais/genética , Transgenes , Animais , Sequência de Bases , Western Blotting , Carcinógenos/toxicidade , Metilação de DNA , Metilases de Modificação do DNA/antagonistas & inibidores , Primers do DNA , Feminino , Inibidores de Histona Desacetilases , Hibridização in Situ Fluorescente , Masculino , Camundongos , Camundongos Transgênicos , Neoplasias Experimentais/induzido quimicamente , Regiões Promotoras Genéticas , Reação em Cadeia da Polimerase Via Transcriptase Reversa
16.
Ann Rheum Dis ; 66(12): 1616-21, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17502362

RESUMO

OBJECTIVE: To investigate whether epigenetic mechanisms can regulate leptin's expression and affect its downstream targets as metalloproteinases 3,9,13 in osteoarthritic chondrocytes. METHODS: DNA methylation in leptin promoter was measured by DNA bisulfite sequencing, and mRNA expression levels were measured by real-time quantitative PCR in osteoarthritic as well as in normal cartilage. Osteoarthritic articular cartilage samples were obtained from two distinct locations of the knee (n = 15); from the main defective area of maximum load (advanced osteoarthritis (OA)) and from adjacent macroscopically intact regions (minimal OA). Using small interference RNA, we tested if leptin downregulation would affect matrix metalloproteinase (MMP)-13 activity. We also evaluated the effect of the demethylating agent, 5'-Aza-2-deoxycytidine (AZA) and of the histone deacetylase inhibitor trichostatin A (TSA) on leptin expression in chondrocyte cultures. Furthermore, we performed chromatin immunoprecipitation in leptin's promoter area. RESULTS: We found a correlation between leptin expression and DNA methylation and also that leptin controls MMP-13 activity in chondrocytes. Leptin's downregulation with small interference RNA inhibited MMP-13 expression dramatically. After 5-AZA application in normal chondrocytes, leptin's methylation was decreased, while its expression was upregulated, and MMP-13 was activated. Furthermore, TSA application in normal chondrocyte cultures increased leptin's expression. Also, chromatin immunoprecipitation in leptin's promoter after TSA treatment revealed that histone H3 lysines 9 and 14 were acetylated. CONCLUSION: We found that epigenetic mechanisms regulate leptin's expression in chondrocytes affecting its downstream target MMP-13. Small interference RNA against leptin deactivated directly MMP-13, which was upregulated after leptin's epigenetic reactivation, raising the issue of leptin's therapeutic potential for osteoarthritis.


Assuntos
Condrócitos/enzimologia , Regulação da Expressão Gênica , Leptina/genética , Metaloproteinase 13 da Matriz/metabolismo , Osteoartrite/metabolismo , Regiões Promotoras Genéticas , Acetilação , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Azacitidina/análogos & derivados , Azacitidina/farmacologia , Western Blotting , Cartilagem Articular/metabolismo , Estudos de Casos e Controles , Condrócitos/metabolismo , Metilação de DNA/efeitos dos fármacos , Metilases de Modificação do DNA/antagonistas & inibidores , Decitabina , Feminino , Expressão Gênica/efeitos dos fármacos , Inibidores de Histona Desacetilases , Histonas/metabolismo , Humanos , Ácidos Hidroxâmicos/farmacologia , Articulação do Joelho , Leptina/metabolismo , Masculino , Metaloproteinase 13 da Matriz/genética , Metaloproteinase 3 da Matriz/genética , Metaloproteinase 3 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Pessoa de Meia-Idade , Interferência de RNA , RNA Interferente Pequeno/farmacologia
17.
Osteoarthritis Cartilage ; 15(8): 872-83, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17350295

RESUMO

OBJECTIVE: To investigate leptin's effect on cartilage metabolism and the pathophysiology of osteoarthritis (OA). METHODS: Messenger RNA (mRNA) expression and protein levels of leptin and leptin's receptor isoforms were measured by real-time reverse transcription-PCR and Western blot in osteoarthritic and normal cartilage. Osteoarthritic cartilage samples were obtained from two locations of the knee (n=11) and hip (n=6); from the main defective area (advanced OA) and from adjacent macroscopically and histological intact regions (minimal OA). Paired serum and synovial fluid (SF) leptin levels were measured. The effect of leptin was evaluated on chondrocyte proliferation, IL-1beta (interleukin-1beta), NO and metalloproteinases 9 and 13 (MMP-9, MMP-13) protein expression. RESULTS: Leptin's and leptin's receptor (Ob-Rb) expression levels were significantly increased in advanced OA cartilage compared to minimal. Leptin was significantly increased in SF than serum samples. Also, leptin had a detrimental effect on chondrocyte proliferation and induced IL-1beta production and MMP-9 and MMP-13 protein expression. Furthermore, leptin's mRNA expression in advanced OA cartilage was significantly correlated with BMI of the patients. CONCLUSION: The increased leptin levels in SF point toward a local effect of leptin in articular cartilage, while the observed intrajoint differences of leptin and Ob-Rb mRNA expression may be related to the grade of cartilage destruction. The observed production of IL-1beta, MMP-9 and MMP-13 by chondrocytes after leptin treatment indicates a pro-inflammatory and catabolic role of leptin on cartilage metabolism. Furthermore, the observed correlation of leptin's mRNA expression with BMI suggests that leptin may be a metabolic link between obesity and OA.


Assuntos
Cartilagem Articular/metabolismo , Leptina/genética , Osteoartrite/genética , Osteoartrite/metabolismo , Receptores para Leptina/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Divisão Celular/fisiologia , Células Cultivadas , Condrócitos/citologia , Condrócitos/fisiologia , Metabolismo Energético/fisiologia , Feminino , Humanos , Interleucina-1/metabolismo , Interleucina-1beta/metabolismo , Isomerismo , Leptina/sangue , Masculino , Metaloproteinase 13 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Pessoa de Meia-Idade , Óxido Nítrico/metabolismo , Obesidade/genética , Obesidade/metabolismo , Obesidade/fisiopatologia , Osteoartrite/patologia , RNA Mensageiro/metabolismo , Receptores para Leptina/química , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Índice de Gravidade de Doença
18.
J Viral Hepat ; 14(1): 41-7, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17212643

RESUMO

We determined, for the first time, the human telomerase reverse transcriptase (hTERT) mRNA expression, using real-time quantitative PCR, in liver tissues from patients with hepatocellular cancer (HCC; n = 13), chronic hepatitis B (n = 19) and C (n = 13). Liver tissues from the 45 patients and 17 patients without liver disease in whom liver biopsy was performed during cholecystectomy (control group), were investigated for telomerase activity (TA) and hTERT mRNA expression using the LightCycler technology. TA was detected in all HCC tissues compared with 15.6% of chronic hepatitis (P < 0.001) and none of controls (P < 0.001). TA levels and hTERT mRNA were higher in HCC compared with chronic hepatitis (P < 0.001) and normal livers (P < 0.001). hTERT mRNA expression was correlated with TA (P < 0.05). Chronic hepatitis patients who tested negative for TA and hTERT mRNA had significantly lower disease duration (58 +/- 85 months) compared with those tested positive (144 +/- 50 months; P < 0.05). Detection of TA and quantification of hTERT mRNA expression in liver tissues could be useful and additional markers for HCC diagnosis and may serve as prognostic markers for HCC development in chronic viral hepatitis patients. However, we were not able to draw general conclusions at this moment, as the number of chronic hepatitis patients positive for hTERT mRNA was relatively small. Real-time quantification of hTERT mRNA expression as a diagnostic/prognostic marker in patients with chronic hepatitis B and C and its relationship with hepatocarcinogenesis needs further evaluation.


Assuntos
Carcinoma Hepatocelular/enzimologia , Hepatite B Crônica/enzimologia , Hepatite C Crônica/enzimologia , Neoplasias Hepáticas/enzimologia , Telomerase/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Feminino , Hepacivirus , Vírus da Hepatite B , Hepatite B Crônica/genética , Hepatite B Crônica/patologia , Hepatite C Crônica/genética , Hepatite C Crônica/patologia , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estatísticas não Paramétricas , Telomerase/biossíntese
19.
Genet Mol Res ; 5(4): 638-42, 2006 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-17183475

RESUMO

The aetiology of congenital bilateral anorchia is unknown. For many years there was speculation of an association between genetic factors and anorchia. We performed different tests in an anorchid boy, 2.5 years old, presented to us with micropenis and absence of both testes, in order to determine any possible factors contributing to the anorchia. Physical examination and hormonal, imaging, chromosomal, and molecular analyses of this case were performed. The basal FSH and LH levels were increased, and their increase in response to gonadotrophin-releasing hormone test was prolonged, while testosterone levels failed to increase after hCG administration. Ultrasonography of the pelvis and magnetic resonance of the abdomen were performed and failed to show any testicular tissue. Lastly, surgical exploration confirmed the absence of testicular structure. Chromosomal analysis revealed a normal male karyotype and molecular analysis did not reveal mutations or polymorphisms in the open reading frame of the SRY gene. Diagnostically, the lack of testosterone response to hCG stimulation is the hormonal hallmark of bilateral congenital anorchia. In addition, according to our case and previous studies, there is lack of association between genetic factors necessary for correct testicular descent and anorchia.


Assuntos
Eunuquismo/congênito , Pênis/anormalidades , Pré-Escolar , Eunuquismo/sangue , Eunuquismo/genética , Hormônio Foliculoestimulante/sangue , Humanos , Cariotipagem , Hormônio Luteinizante/sangue , Imageamento por Ressonância Magnética , Masculino , Reação em Cadeia da Polimerase , Radioimunoensaio , Testosterona/sangue
20.
Oncogene ; 25(20): 2860-72, 2006 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-16407838

RESUMO

The Fhit tumor suppressor binds and hydrolyses diadenosine polyphosphates and the Fhit-substrate complex has been proposed as a proapoptotic effector, as determined by infection of susceptible cancer cells with adenoviruses carrying wild-type fragile histidine triad (FHIT) or catalytic site mutants. The highly conserved Fhit tyrosine 114 (Y114), within the unstructured loop C-terminal of the catalytic site, can be phosphorylated by Src family tyrosine kinases, although endogenous phospho-Fhit is rarely detected. To explore the importance of Y114 and identify Fhit-mediated signaling events, wild-type and Y114 mutant FHIT-expressing adenoviruses were introduced into two human lung cancer cell lines. Caspase-dependent apoptosis was effectively induced only by wild-type but not Y114 mutant Fhit proteins. By expression profiling of FHIT versus mutant FHIT-infected cells, we found that survivin, an Inhibitor of Apoptosis Protein (IAP) family member, was significantly decreased by wild-type Fhit. In addition, Fhit inhibited activity of Akt, a key effector in the phosphatidylinositol 3-OH kinase (PI3K) pathway; loss of endogenous Fhit expression caused increased Akt activity in vitro and in vivo, and overexpression of constitutively active Akt inhibited Fhit-induced apoptosis. The results indicate that the Fhit Y114 residue plays a critical role in Fhit-induced apoptosis, occurring through inactivation of the PI3K-Akt-survivin signal pathway.


Assuntos
Hidrolases Anidrido Ácido/genética , Regulação da Expressão Gênica/fisiologia , Genes Supressores de Tumor/fisiologia , Neoplasias Pulmonares/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Tirosina/metabolismo , Adenoviridae/genética , Western Blotting , Classe I de Fosfatidilinositol 3-Quinases , Citometria de Fluxo , Perfilação da Expressão Gênica , Humanos , Proteínas Inibidoras de Apoptose , Neoplasias Pulmonares/genética , Proteínas Associadas aos Microtúbulos/genética , Análise de Sequência com Séries de Oligonucleotídeos , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , RNA Interferente Pequeno/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Survivina , Células Tumorais Cultivadas , Tirosina/genética
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