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1.
Children (Basel) ; 10(9)2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37761428

RESUMO

Here, we report the perioperative management of a clinical case of a 6 year, 5 month old girl suffering from Beckwith-Wiedemann syndrome undergoing a partial glossectomy procedure in a patient with surgical indication for obstructive sleep apnea syndrome (OSAS), difficulty swallowing, feeding, and speech. On surgery day, Clonidine (4 µg/kg) was administered. Following this, a general anesthesia induction was performed by administering Sevoflurane, Fentanyl, continuous intravenous Remifentanil, and lidocaine to the vocal cords, and a rhinotracheal intubation with a size 4.5 tube was carried out. Before starting the procedure, a block of the Lingual Nerve was performed with Levobupivacaine. Analgosedation was maintained with 3% Sevoflurane in air and oxygen (FiO2 of 40%) and Remifentanil in continuous intravenous infusion at a rate of 0.08-0.15 µg/kg/min. The surgical procedure lasted 2 h and 32 min. At the end of the surgery, the patient was under close observation during the first 72 h. In the pediatric patient with Beckwith-Wiedemann syndrome submitted to major maxillofacial surgery, the difficulty in managing the airways in the preoperative phase during intubation and in the post-operative phase during extubation should be considered.

2.
Aging Cell ; 21(2): e13539, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35088525

RESUMO

Mild uncoupling of oxidative phosphorylation is an intrinsic property of all mitochondria and may have evolved to protect cells against the production of damaging reactive oxygen species. Therefore, compounds that enhance mitochondrial uncoupling are potentially attractive anti-aging therapies; however, chronic ingestion is associated with a number of unwanted side effects. We have previously developed a controlled-release mitochondrial protonophore (CRMP) that is functionally liver-directed and promotes oxidation of hepatic triglycerides by causing a subtle sustained increase in hepatic mitochondrial inefficiency. Here, we sought to leverage the higher therapeutic index of CRMP to test whether mild mitochondrial uncoupling in a liver-directed fashion could reduce oxidative damage and improve age-related metabolic disease and lifespan in diet-induced obese mice. Oral administration of CRMP (20 mg/[kg-day] × 4 weeks) reduced hepatic lipid content, protein kinase C epsilon activation, and hepatic insulin resistance in aged (74-week-old) high-fat diet (HFD)-fed C57BL/6J male mice, independently of changes in body weight, whole-body energy expenditure, food intake, or markers of hepatic mitochondrial biogenesis. CRMP treatment was also associated with a significant reduction in hepatic lipid peroxidation, protein carbonylation, and inflammation. Importantly, long-term (49 weeks) hepatic mitochondrial uncoupling initiated late in life (94-104 weeks), in conjugation with HFD feeding, protected mice against neoplastic disorders, including hepatocellular carcinoma (HCC), in a strain and sex-specific manner. Taken together, these studies illustrate the complex variation of aging and provide important proof-of-concept data to support further studies investigating the use of liver-directed mitochondrial uncouplers to promote healthy aging in humans.


Assuntos
Carcinoma Hepatocelular , Resistência à Insulina , Neoplasias Hepáticas , Animais , Carcinoma Hepatocelular/metabolismo , Dieta Hiperlipídica/efeitos adversos , Feminino , Fígado/metabolismo , Neoplasias Hepáticas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo
3.
J Gerontol A Biol Sci Med Sci ; 77(5): 956-963, 2022 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-34718551

RESUMO

Age-dependent differences in methylation at specific cytosine-guanine (CpG) sites have been used in "epigenetic clock" formulas to predict age. Deviations of epigenetic age from chronological age are informative of health status and are associated with adverse health outcomes, including mortality. In most cases, epigenetic clocks are performed on methylation from DNA extracted from circulating blood cells. However, the effect of neoplastic cells in the circulation on estimation and interpretation of epigenetic clocks is not well understood. Here, we explored this using Fischer 344 (F344) rats, a strain that often develops large granular lymphocyte leukemia (LGLL). We found clear histological markers of LGLL pathology in the spleens and livers of 27 out of 61 rats aged 17-27 months. We assessed DNA methylation by reduced representation bisulfite sequencing with coverage of 3 million cytosine residues. Although LGLL broadly increased DNA methylation variability, it did not change epigenetic aging. Despite this, the inclusion of rats with LGLL in clock training sets significantly altered predictor selection probability at 83 of 121 commonly utilized CpG sites. Furthermore, models trained on rat samples that included individuals with LGLL had greater absolute age error than those trained exclusively rats free of LGLL (39% increase; p < .0001). We conclude that the epigenetic signals for aging and LGLL are distinct, such that LGLL assessment is not necessary for valid measures of epigenetic age in F344 rats. The precision and architecture of constructed epigenetic clock formulas, however, can be influenced by the presence of neoplastic hematopoietic cells in training set populations.


Assuntos
Metilação de DNA , Leucemia Linfocítica Granular Grande , Envelhecimento/genética , Animais , Citosina , Epigênese Genética , Leucemia Linfocítica Granular Grande/genética , Ratos , Ratos Endogâmicos F344
4.
Cell Metab ; 32(2): 203-214.e4, 2020 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-32413333

RESUMO

Obesity is a top public health concern, and a molecule that safely treats obesity is urgently needed. Disulfiram (known commercially as Antabuse), an FDA-approved treatment for chronic alcohol addiction, exhibits anti-inflammatory properties and helps protect against certain types of cancer. Here, we show that in mice disulfiram treatment prevented body weight gain and abrogated the adverse impact of an obesogenic diet on insulin responsiveness while mitigating liver steatosis and pancreatic islet hypertrophy. Additionally, disulfiram treatment reversed established diet-induced obesity and metabolic dysfunctions in middle-aged mice. Reductions in feeding efficiency and increases in energy expenditure were associated with body weight regulation in response to long-term disulfiram treatment. Loss of fat tissue and an increase in liver fenestrations were also observed in rats on disulfiram. Given the potent anti-obesogenic effects in rodents, repurposing disulfiram in the clinic could represent a new strategy to treat obesity and its metabolic comorbidities.


Assuntos
Fármacos Antiobesidade/farmacologia , Peso Corporal/efeitos dos fármacos , Dissulfiram/farmacologia , Obesidade/tratamento farmacológico , Animais , Dieta/efeitos adversos , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Obesidade/induzido quimicamente , Obesidade/metabolismo , Ratos , Ratos Sprague-Dawley
5.
Front Immunol ; 10: 1347, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31316498

RESUMO

5-lipoxygenase (5-LOX) is a non-heme iron-containing dioxygenase expressed in immune cells that catalyzes the two initial steps in the biosynthesis of leukotrienes. It is well known that 5-LOX activation in innate immunity cells is related to different iron-associated pro-inflammatory disorders, including cancer, neurodegenerative diseases, and atherosclerosis. However, the molecular and cellular mechanism(s) underlying the interplay between iron and 5-LOX activation are largely unexplored. In this study, we investigated whether iron (in the form of Fe3+ and hemin) might modulate 5-LOX influencing its membrane binding, subcellular distribution, and functional activity. We proved by fluorescence resonance energy transfer approach that metal removal from the recombinant human 5-LOX, not only altered the catalytic activity of the enzyme, but also impaired its membrane-binding. To ascertain whether iron can modulate the subcellular distribution of 5-LOX in immune cells, we exposed THP-1 macrophages and human primary macrophages to exogenous iron. Cells exposed to increasing amounts of Fe3+ showed a redistribution (ranging from ~45 to 75%) of the cytosolic 5-LOX to the nuclear fraction. Accordingly, confocal microscopy revealed that acute exposure to extracellular Fe3+, as well as hemin, caused an overt increase in the nuclear fluorescence of 5-LOX, accompanied by a co-localization with the 5-LOX activating protein (FLAP) both in THP-1 macrophages and human macrophages. The functional relevance of iron overloading was demonstrated by a marked induction of the expression of interleukin-6 in iron-treated macrophages. Importantly, pre-treatment of cells with the iron-chelating agent deferoxamine completely abolished the hemin-dependent translocation of 5-LOX to the nuclear fraction, and significantly reverted its effect on interleukin-6 overexpression. These results suggest that exogenous iron modulates the biological activity of 5-LOX in macrophages by increasing its ability to bind to nuclear membranes, further supporting a role for iron in inflammation-based diseases where its homeostasis is altered and suggesting further evidence of risks related to iron overload.


Assuntos
Araquidonato 5-Lipoxigenase/metabolismo , Ferro/farmacologia , Macrófagos/efeitos dos fármacos , Araquidonato 5-Lipoxigenase/genética , Células Cultivadas , Hemina/farmacologia , Humanos , Ativação de Macrófagos , Macrófagos/enzimologia
6.
J Gerontol A Biol Sci Med Sci ; 74(2): 155-162, 2019 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-29733330

RESUMO

Caloric restriction (CR) is the most potent nonpharmacological intervention known to both protect against carcinogenesis and delay aging in laboratory animals. There is a growing number of anticarcinogens and CR mimetics that activate NAD(P)H:quinone oxidoreductase 1 (NQO1). We have previously shown that NQO1, an antioxidant enzyme that acts as an energy sensor through modulation of intracellular redox and metabolic state, is upregulated by CR. Here, we used NQO1-knockout (KO) mice to investigate the role of NQO1 in both the aging process and tumor susceptibility, specifically in the context of CR. We found that NQO1 is not essential for the beneficial effects of CR on glucose homeostasis, physical performance, metabolic flexibility, life-span extension, and (unlike our previously observation with Nrf2) chemical-induced tumorigenesis.


Assuntos
Composição Corporal , Restrição Calórica/efeitos adversos , Longevidade , NAD(P)H Desidrogenase (Quinona)/metabolismo , Neoplasias Experimentais/prevenção & controle , Estresse Oxidativo , Animais , Biomarcadores Tumorais/metabolismo , Carcinogênese , Immunoblotting , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neoplasias Experimentais/etiologia , Neoplasias Experimentais/metabolismo
7.
J Heart Lung Transplant ; 37(11): 1329-1340, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30174164

RESUMO

BACKGROUND: Identification of heart transplant (HTx) rejection currently relies on immunohistology and immunohistochemistry. We aimed to identify specific sets of microRNAs (miRNAs) to characterize acute cellular rejection (ACR), antibody-mediated rejection (pAMR), and mixed rejection (MR) in monitoring formalin-fixed paraffin-embedded (FFPE) endomyocardial biopsies (EMBs) in HTx patients. METHODS: In this study we selected 33 adult HTx patients. For each, we chose the first positive EMB for study of each type of rejection. The next-generation sequencing (NGS) IonProton technique and reverse transcript quantitative polymerase chain reaction (RT-qPCR) analysis were performed on FFPE EMBs. Using logistic regression analysis we created unique miRNA signatures as predictive models of each rejection. In situ PCR was carried out on the same EMBs. RESULTS: We obtained >2,257 mature miRNAs from all the EMBs. The 3 types of rejection showed a different miRNA profile for each group. The logistic regression model formed by miRNAs 208a, 126-5p, and 135a-5p identified MR; that formed by miRNAs 27b-3p, 29b-3p, and 199a-3p identified ACR; and that formed by miRNAs 208a, 29b-3p, 135a-5p, and 144-3p identified pAMR. The expression of miRNAs on tissue, through in situ PCR, showed different expressions of the same miRNA in different rejections. miRNA 126-5p was expressed in endothelial cells in ACR but in cardiomyocytes in pAMR. In ACR, miRNA 29b-3p was significantly overexpressed and detected in fibroblasts, whereas in pAMR it was underexpressed and detected only in cardiomyocytes. CONCLUSIONS: miRNA profiling on FFPE EMBs differentiates the 3 types of rejection. Localization of expression of miRNAs on tissue showed different expression of the same miRNA for different cells, suggesting different roles of the same miRNA in different rejections.


Assuntos
Rejeição de Enxerto/genética , Transplante de Coração , MicroRNAs/genética , Miocárdio/patologia , Transcriptoma/genética , Adulto , Idoso , Biópsia , Feminino , Rejeição de Enxerto/patologia , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase
8.
Aging Cell ; 17(4): e12767, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29706024

RESUMO

Calorie restriction (CR) is one of the most robust means to improve health and survival in model organisms. CR imposes a metabolic program that leads to increased stress resistance and delayed onset of chronic diseases, including cancer. In rodents, CR induces the upregulation of two NADH-dehydrogenases, namely NAD(P)H:quinone oxidoreductase 1 (Nqo1) and cytochrome b5 reductase 3 (Cyb5r3), which provide electrons for energy metabolism. It has been proposed that this upregulation may be responsible for some of the beneficial effects of CR, and defects in their activity are linked to aging and several age-associated diseases. However, it is unclear whether changes in metabolic homeostasis solely through upregulation of these NADH-dehydrogenases have a positive impact on health and survival. We generated a mouse that overexpresses both metabolic enzymes leading to phenotypes that resemble aspects of CR including a modest increase in lifespan, greater physical performance, a decrease in chronic inflammation, and, importantly, protection against carcinogenesis, one of the main hallmarks of CR. Furthermore, these animals showed an enhancement of metabolic flexibility and a significant upregulation of the NAD+ /sirtuin pathway. The results highlight the importance of these NAD+ producers for the promotion of health and extended lifespan.


Assuntos
Restrição Calórica , Citocromo-B(5) Redutase/genética , Regulação Enzimológica da Expressão Gênica , NAD(P)H Desidrogenase (Quinona)/genética , Animais , Citocromo-B(5) Redutase/metabolismo , Metabolismo Energético , Longevidade , Masculino , Camundongos , Camundongos Transgênicos , NAD(P)H Desidrogenase (Quinona)/metabolismo , Ratos
9.
Free Radic Biol Med ; 99: 225-233, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27515817

RESUMO

NAD(P)H: quinone oxidoreductase (NQO1) is essential for cell defense against reactive oxidative species, cancer, and metabolic stress. Recently, NQO1 was found in ribonucleoprotein (RNP) complexes, but NQO1-interacting mRNAs and the functional impact of such interactions are not known. Here, we used ribonucleoprotein immunoprecipitation (RIP) and microarray analysis to identify comprehensively the subset of NQO1 target mRNAs in human hepatoma HepG2 cells. One of its main targets, SERPINA1 mRNA, encodes the serine protease inhibitor α-1-antitrypsin, A1AT, which is associated with disorders including obesity-related metabolic inflammation, chronic obstructive pulmonary disease (COPD), liver cirrhosis and hepatocellular carcinoma. Biotin pulldown analysis indicated that NQO1 can bind the 3' untranslated region (UTR) and the coding region (CR) of SERPINA1 mRNA. NQO1 did not affect SERPINA1 mRNA levels; instead, it enhanced the translation of SERPINA1 mRNA, as NQO1 silencing decreased the size of polysomes forming on SERPINA1 mRNA and lowered the abundance of A1AT. Luciferase reporter analysis further indicated that NQO1 regulates SERPINA1 mRNA translation through the SERPINA1 3'UTR. Accordingly, NQO1-KO mice had reduced hepatic and serum levels of A1AT and increased activity of neutrophil elastase (NE), one of the main targets of A1AT. We propose that this novel mechanism of action of NQO1 as an RNA-binding protein may help to explain its pleiotropic biological effects.


Assuntos
NAD(P)H Desidrogenase (Quinona)/genética , Biossíntese de Proteínas , RNA Mensageiro/genética , alfa 1-Antitripsina/genética , Animais , Sítios de Ligação , Regulação da Expressão Gênica , Genes Reporter , Células Hep G2 , Humanos , Elastase de Leucócito/genética , Elastase de Leucócito/metabolismo , Luciferases/genética , Luciferases/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Análise em Microsséries , NAD(P)H Desidrogenase (Quinona)/antagonistas & inibidores , NAD(P)H Desidrogenase (Quinona)/metabolismo , Ligação Proteica , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Ribonucleoproteínas/genética , Ribonucleoproteínas/metabolismo , Transdução de Sinais , alfa 1-Antitripsina/metabolismo
10.
J Nutr Biochem ; 26(3): 250-8, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25533906

RESUMO

Extravirgin olive oil (EVOO) represents the typical lipid source of the Mediterranean diet, an eating habit pattern that has been associated with a significant reduction of cancer risk. Diet is the more studied environmental factor in epigenetics, and many evidences suggest dysregulation of epigenetic pathways in cancer. The aim of our study was to investigate the effects of EVOO and its phenolic compounds on endocannabinoid system (ECS) gene expression via epigenetic regulation in both human colon cancer cells (Caco-2) and rats exposed to short- and long-term dietary EVOO. We observed a selective and transient up-regulation of CNR1 gene - encoding for type 1 cannabinoid receptor (CB1) - that was evoked by exposure of Caco-2 cells to EVOO (100 ppm), its phenolic extracts (OPE, 50 µM) or authentic hydroxytyrosol (HT, 50 µM) for 24 h. None of the other major elements of the ECS (i.e., CB2; GPR55 and TRPV1 receptors; and NAPE-PLD, DAGL, FAAH and MAGL enzymes) was affected at any time point. The stimulatory effect of OPE and HT on CB1 expression was inversely correlated to DNA methylation at CNR1 promoter and was associated with reduced proliferation of Caco-2 cells. Interestingly, CNR1 gene was less expressed in Caco-2 cells when compared to normal colon mucosa cells, and again this effect was associated with higher level of DNA methylation at CNR1. Moreover, in agreement with the in vitro studies, we also observed a remarkable (~4-fold) and selective increase in CB1 expression in the colon of rats receiving dietary EVOO supplementation for 10 days. Consistently, CpG methylation of rat Cnr1 promoter, miR23a and miR-301a, previously shown to be involved in the pathogenesis of colorectal cancer and predicted to target CB1 mRNA, was reduced after EVOO administration down to ~50% of controls. Taken together, our findings demonstrating CB1 gene expression modulation by EVOO or its phenolic compounds via epigenetic mechanism, both in vitro and in vivo, may provide a new therapeutic avenue for treatment and/or prevention of colon cancer.


Assuntos
Colo/metabolismo , Neoplasias do Colo/metabolismo , Epigênese Genética , Óleos de Plantas/metabolismo , Receptor CB1 de Canabinoide/agonistas , Receptor CB1 de Canabinoide/metabolismo , Regulação para Cima , Animais , Células CACO-2 , Linhagem Celular , Proliferação de Células , Colo/citologia , Colo/patologia , Neoplasias do Colo/patologia , Neoplasias do Colo/prevenção & controle , Metilação de DNA , Gorduras Insaturadas na Dieta/metabolismo , Gorduras Insaturadas na Dieta/normas , Gorduras Insaturadas na Dieta/uso terapêutico , Feminino , Frutas/química , Humanos , Mucosa Intestinal/citologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Proteínas de Neoplasias/agonistas , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Olea/química , Azeite de Oliva , Álcool Feniletílico/análogos & derivados , Álcool Feniletílico/metabolismo , Extratos Vegetais/metabolismo , Óleos de Plantas/química , Óleos de Plantas/normas , Regiões Promotoras Genéticas , Ratos Sprague-Dawley , Receptor CB1 de Canabinoide/química , Receptor CB1 de Canabinoide/genética
11.
Int J Mol Sci ; 14(9): 17881-96, 2013 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-24002026

RESUMO

Perturbations during the cell DNA-Damage Response (DDR) can originate from alteration in the functionality of the microRNA-mediated gene regulation, being microRNAs (miRNAs), small non-coding RNAs that act as post-transcriptional regulators of gene expression. The oncogenic miR-27a is over-expressed in several tumors and, in the present study, we investigated its interaction with ATM, the gene coding for the main kinase of DDR pathway. Experimental validation to confirm miR-27a as a direct regulator of ATM was performed by site-direct mutagenesis of the luciferase reporter vector containing the 3'UTR of ATM gene, and by miRNA oligonucleotide mimics. We then explored the functional miR-27a/ATM interaction under biological conditions, i.e., during the response of A549 cells to ionizing radiation (IR) exposure. To evaluate if miR-27a over-expression affects IR-induced DDR activation in A549 cells we determined cell survival, cell cycle progression and DNA double-strand break (DSB) repair. Our results show that up-regulation of miR-27a promotes cell proliferation of non-irradiated and irradiated cells. Moreover, increased expression of endogenous mature miR-27a in A549 cells affects DBS rejoining kinetics early after irradiation.


Assuntos
Raios gama/efeitos adversos , Regiões 3' não Traduzidas/genética , Proteínas Mutadas de Ataxia Telangiectasia/genética , Linhagem Celular , Dano ao DNA/efeitos da radiação , Humanos , MicroRNAs/genética
12.
J Immunol ; 184(4): 2140-7, 2010 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-20065114

RESUMO

NO-donating aspirins consist of aspirin to which a NO-donating group is covalently linked via a spacer molecule. NCX 4040 and NCX 4016 are positional isomers with respect to the -CH(2)ONO(2) group (para and meta, respectively) on the benzene ring of the spacer. Because positional isomerism is critical for antitumor properties of NO-donating aspirins, we aimed to compare their anti-inflammatory effects with those of aspirin in vitro. Thus, we assessed their impacts on cyclooxygenase-2 activity (by measuring PGE(2) levels), protein expression, and cytokine generation(IL-1beta, IL-18, TNF-alpha, and IL-10) in human whole blood and isolated human monocytes stimulated with LPS. Interestingly, we found that micromolar concentrations of NCX 4040, but not NCX 4016 or aspirin, affected cyclooxygenase-2 expression and cytokine generation. We compared the effects of NCX 4040 with those of NCX 4016 or aspirin on IkappaB-alpha stabilization and proteasome activity in the LPS-stimulated human monocytic cell line THP1. Differently from aspirin and NCX 4016, NCX 4040, at a micromolar concentration range, inhibited IkappaB-alpha degradation. In fact, NCX 4040 caused concentration-dependent accumulation of IkappaB-alpha and its phosphorylated form. This effect was not reversed by 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one, an inhibitor of guanylyl cyclase, thus excluding the contribution of NO-dependent cGMP generation. In contrast, IkappaB-alpha accumulation by NCX 4040 may involve an inhibitory effect on proteasome functions. Indeed, NCX 4040 inhibited 20S proteasome activity when incubated with intact cells but not in the presence of cell lysate supernatants, thus suggesting an indirect inhibitory effect. In conclusion, NCX 4040 is an inhibitor of IkappaB-alpha degradation and proteasome function, and it should be taken into consideration for the development of novel anti-inflammatory and chemopreventive agents.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Aspirina/análogos & derivados , Proteínas I-kappa B/antagonistas & inibidores , Proteínas I-kappa B/metabolismo , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Doadores de Óxido Nítrico/farmacologia , Nitrocompostos/farmacologia , Adulto , Anti-Inflamatórios não Esteroides/química , Aspirina/química , Aspirina/farmacologia , Plaquetas/efeitos dos fármacos , Plaquetas/enzimologia , Linhagem Celular Tumoral , Ciclo-Oxigenase 1/sangue , Ciclo-Oxigenase 2/sangue , Dinoprostona/biossíntese , Dinoprostona/sangue , Humanos , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/fisiologia , Inibidor de NF-kappaB alfa , Doadores de Óxido Nítrico/química , Nitrocompostos/química , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia
13.
Biochem Pharmacol ; 79(7): 974-81, 2010 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-19925781

RESUMO

Inhibitors of microsomal prostaglandin (PG) E synthase-1 (mPGES-1) are being developed for the relief of pain. Redirection of the PGH(2) substrate to other PG synthases, found both in vitro and in vivo, in mPGES-1 knockout mice, may influence their efficacy and safety. We characterized the contribution of mPGES-1 to PGH(2) metabolism in lipopolysaccharide (LPS)-stimulated isolated human monocytes and whole blood by studying the synthesis of prostanoids [PGE(2), thromboxane (TX)B(2), PGF(2alpha) and 6-keto-PGF(1alpha)] and expression of cyclooxygenase (COX)-isozymes and down-stream synthases in the presence of pharmacological inhibition by the novel mPGES-1 inhibitor AF3442 [N-(9-ethyl-9H-carbazol-3-yl)-2-(trifluoromethyl)benzamide]. AF3442 caused a concentration-dependent inhibition of PGE(2) in human recombinant mPGES-1 with an IC(50) of 0.06microM. In LPS-stimulated monocytes, AF3442 caused a concentration-dependent reduction of PGE(2) biosynthesis with an IC(50) of 0.41microM. At 1microM, AF3442 caused maximal selective inhibitory effect of PGE(2) biosynthesis by 61+/-3.3% (mean+/-SEM, P<0.01 versus DMSO vehicle) without significantly affecting other prostanoids (i.e. TXB(2), PGF(2alpha) and 6-keto-PGF(1alpha)). In LPS-stimulated whole blood, AF3442 inhibited in a concentration-dependent fashion inducible PGE(2) biosynthesis with an IC(50) of 29microM. A statistically significant inhibition of mPGES-1 activity was detected at 10 and 100microM (38+/-14%, P<0.05, and 69+/-5%, P<0.01, respectively). Up to 100microM, the other prostanoids were not significantly affected. In conclusion, AF3442 is a selective mPGES-1 inhibitor which reduced monocyte PGE(2) generation also in the presence of plasma proteins. Pharmacological inhibition of mPGES-1 did not translate into redirection of PGH(2) metabolism towards other terminal PG synthases in monocytes. The functional relevance of this observation deserves to be investigated in vivo.


Assuntos
Benzamidas/farmacologia , Carbazóis/farmacologia , Inibidores Enzimáticos/farmacologia , Oxirredutases Intramoleculares/antagonistas & inibidores , Monócitos/metabolismo , Prostaglandinas/biossíntese , Linhagem Celular Tumoral , Dinoprostona/biossíntese , Relação Dose-Resposta a Droga , Epoprostenol/biossíntese , Humanos , Lipopolissacarídeos/farmacologia , Microssomos/enzimologia , Prostaglandina H2/biossíntese , Prostaglandina-E Sintases
14.
Circ Res ; 104(4): 506-13, 2009 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-19122175

RESUMO

Cyclooxygenase (COX)-2 is among the endothelial genes upregulated by uniform laminar shear stress (LSS), characteristically associated with atherosclerotic lesion-protected areas. We have addressed whether the induction of COX-2-dependent prostanoids in endothelial cells by LSS plays a role in restraining endothelial tumor necrosis factor (TNF)-alpha generation, a proatherogenic cytokine, through the induction of heme oxygenase-1 (HO)-1, an antioxidant enzyme. In human umbilical vein endothelial cells (HUVECs) exposed to steady LSS of 10 dyn/cm(2) for 6 hours, COX-2 protein was significantly induced, whereas COX-1 and the downstream synthases were not significantly modulated. This was associated with significant (P<0.05) increase of 6-keto-prostaglandin (PG)F(1alpha) (the hydrolysis product of prostacyclin), PGE(2), and PGD(2). In contrast, TNF-alpha released in the medium in 6 hours (3633+/-882 pg) or detected in cells lysates (1091+/-270 pg) was significantly (P<0.05) reduced versus static condition (9100+/-2158 and 2208+/-300 pg, respectively). Coincident induction of HO-1 was detected. The finding that LSS-dependent reduction of TNF-alpha generation and HO-1 induction were abrogated by the selective inhibitor of COX-2 NS-398, the nonselective COX inhibitor aspirin, or the specific prostacyclin receptor (IP) antagonist RO3244794 illuminates the central role played by LSS-induced COX-2-dependent prostacyclin in restraining endothelial inflammation. Carbacyclin, an agonist of IP, induced HO-1. Similarly to inhibition of prostacyclin biosynthesis or activity, the novel imidazole-based HO-1 inhibitor QC15 reversed TNF-alpha reduction by LSS. These findings suggest that inhibition of COX-2-dependent prostacyclin might contribute to acceleration of atherogenesis in patients taking traditional nonsteroidal antiinflammatory drugs (NSAIDs) and NSAIDs selective for COX-2 through downregulation of HO-1, which halts TNF-alpha generation in human endothelial cells.


Assuntos
Aterosclerose/enzimologia , Ciclo-Oxigenase 2/metabolismo , Células Endoteliais/enzimologia , Epoprostenol/metabolismo , Heme Oxigenase-1/metabolismo , Inflamação/enzimologia , Fator de Necrose Tumoral alfa/biossíntese , 6-Cetoprostaglandina F1 alfa , Aspirina/efeitos adversos , Aspirina/farmacologia , Aterosclerose/induzido quimicamente , Benzofuranos/farmacologia , Células Cultivadas , Ciclo-Oxigenase 1/metabolismo , Inibidores de Ciclo-Oxigenase/efeitos adversos , Inibidores de Ciclo-Oxigenase/farmacologia , Dinoprosta/metabolismo , Dinoprostona/metabolismo , Regulação para Baixo , Células Endoteliais/efeitos dos fármacos , Epoprostenol/análogos & derivados , Epoprostenol/farmacologia , Humanos , Inflamação/induzido quimicamente , Nitrobenzenos/efeitos adversos , Nitrobenzenos/farmacologia , Perfusão , Propionatos/farmacologia , Prostaglandina D2/metabolismo , Receptores de Epoprostenol , Receptores de Prostaglandina/efeitos dos fármacos , Receptores de Prostaglandina/metabolismo , Estresse Mecânico , Sulfonamidas/efeitos adversos , Sulfonamidas/farmacologia , Regulação para Cima
15.
Arterioscler Thromb Vasc Biol ; 26(12): 2716-23, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17038636

RESUMO

OBJECTIVE: Receptor for advanced glycation end products (AGEs) (RAGE) plays a central role in the process of plaque rupture in diabetic patients. Recently, it has been reported that RAGE may be downregulated by improving glycemic control. In contrast, despite being well known that RAGE may be induced in human vessels in a glucose-independent fashion, also by myeloperoxidase (MPO)-dependent AGE generation, no data exist regarding the possibility of a pharmacological modulation of glucose-independent RAGE generation. Thus, the aim of this study was to characterize the effect of simvastatin on the expression of RAGE and RAGE-dependent plaque-destabilizing genes in human atherosclerotic plaques. METHODS AND RESULTS: Seventy type 2 diabetic patients with asymptomatic carotid artery stenosis (>70%) were randomized to American Heart Association (AHA) step 1 diet plus simvastatin (40 mg/d) or AHA step 1 diet alone for 4 months before endarterectomy. Plaque expression of MPO, AGEs, RAGE, NF-kappaB, COX-2, mPGES-1, matrix metalloproteinase (MMP)-2 and MMP-9, lipid and oxidized LDL (oxLDL) content, procollagen 1, and interstitial collagen was analyzed by immunohistochemistry and Western blot; zymography was used to detect MMP activity. Plaques from the simvastatin group had less (P<0.0001) immunoreactivity for MPO, AGEs, RAGE, p65, COX-2, mPGES-1, MMP-2, and MMP-9, lipids and oxLDL; reduced (P<0.0001) gelatinolytic activity; increased (P<0.0001) procollagen 1 and collagen content; and fewer (P<0.0001) macrophages, T-lymphocytes, and HLA-DR+ cells. Of interest, RAGE inhibition by simvastatin, observed not only in plaque sections but also in plaque-derived macrophages, was reverted by addition of AGEs in vitro. CONCLUSIONS: This study supports the hypothesis that simvastatin inhibits plaque RAGE expression by decreasing MPO-dependent AGE generation. This effect in turn might contribute to plaque stabilization by inhibiting the biosynthesis of PGE2-dependent MMPs, responsible for plaque rupture.


Assuntos
Anticolesterolemiantes/farmacologia , Estenose das Carótidas/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Receptores Imunológicos/metabolismo , Sinvastatina/farmacologia , Idoso , Estenose das Carótidas/patologia , Células Cultivadas , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/patologia , Feminino , Regulação da Expressão Gênica/genética , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/genética , Glucose/metabolismo , Produtos Finais de Glicação Avançada/genética , Produtos Finais de Glicação Avançada/metabolismo , Humanos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/patologia , Masculino , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , NF-kappa B/genética , NF-kappa B/metabolismo , Peroxidase/genética , Peroxidase/metabolismo , Receptor para Produtos Finais de Glicação Avançada , Receptores Imunológicos/genética
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