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1.
Scand J Trauma Resusc Emerg Med ; 28(1): 68, 2020 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-32678052

RESUMO

INTRODUCTION: In emergency care, geriatric requirements and risks are often not taken sufficiently into account. In addition, there are neither evidence-based recommendations nor scientifically developed quality indicators (QI) for geriatric emergency care in German emergency departments. As part of the GeriQ-ED© research project, quality indicators for geriatric emergency medicine in Germany have been developed using the QUALIFY-instruments. METHODS: Using a triangulation methodology, a) clinical experience-based quality aspects were identified and verified, b) research-based quality statements were formulated and assessed for relevance, and c) preliminary quality indicators were operationalized and evaluated in order to recommend a feasible set of final quality indicators. RESULTS: Initially, 41 quality statements were identified and assessed as relevant. Sixty-seven QI (33 process, 29 structure and 5 outcome indicators) were extrapolated and operationalised. In order to facilitate implementation into daily practice, the following five quality statements were defined as the GeriQ-ED© TOP 5: screening for delirium, taking a full medications history including an assessment of the indications, education of geriatric knowledge and skills to emergency staff, screening for patients with geriatric needs, and identification of patients with risk of falls/ recurrent falls. DISCUSSION: QIs are regarded as gold standard to measure, benchmark and improve emergency care. GeriQ-ED© QI focused on clinical experience- and research-based recommendations and describe for the first time a standard for geriatric emergency care in Germany. GeriQ-ED© TOP 5 should be implemented as a minimum standard in geriatric emergency care.


Assuntos
Medicina de Emergência/normas , Serviço Hospitalar de Emergência , Avaliação Geriátrica , Geriatria/normas , Indicadores de Qualidade em Assistência à Saúde , Acidentes por Quedas/prevenção & controle , Idoso , Delírio/diagnóstico , Técnica Delphi , Humanos , Capacitação em Serviço , Programas de Rastreamento/normas , Reconciliação de Medicamentos , Avaliação das Necessidades , Melhoria de Qualidade , Medição de Risco
2.
Sci Rep ; 9(1): 11079, 2019 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-31366894

RESUMO

LDL-cholesterol (LDL-C) is a causal pathogenic factor in atherosclerosis. Monoclonal anti-proprotein convertase subtilisin/kexin type 9 (PCSK9) neutralizing antibodies are novel potent LDL-lowering drugs which reduce cardiovascular events. To characterize their effect on atherogenesis, APOE*3Leiden.CETP mice were fed a high cholesterol/high fat diet (WTD) or normal chow (NC) for 18 weeks. Mice on WTD were injected with the human anti-PCSK9 antibody mAb1 (PL-45134, 10 mg*kg-1 s.c.) or 0.9% saline every 10 days. PCSK9 inhibition decreased total cholesterol in serum of APOE*3Leiden.CETP mice and prevented the development of atherosclerosis. The plaque area in the aortic root was reduced by half and macrophage infiltration determined by Ly6c and Mac-3 staining was ameliorated. PCSK9 inhibition decreased markers of inflammation in mononuclear cells (Il-6, Tnfa mRNA), and in serum (CXCL-1,-10,-13; complement factor C5a) compared to control WTD fed animals. The number of circulating Sca-1/VEGF-R2 positive endothelial progenitor cells of the peripheral blood and spleen-derived diLDL/lectin double positive circulating angiogenic cells was increased. To conclude, the PCSK9-mediated anti-atherosclerotic effect involves the upregulation of pro-regeneratory endothelial progenitor cells, a reduction of inflammation and change of plaque composition.


Assuntos
Apolipoproteínas E/metabolismo , Aterosclerose/metabolismo , Placa Aterosclerótica/metabolismo , Pró-Proteína Convertase 9/metabolismo , Animais , Anticorpos Monoclonais/fisiologia , Aterosclerose/tratamento farmacológico , Colesterol/metabolismo , LDL-Colesterol/metabolismo , Células Progenitoras Endoteliais/efeitos dos fármacos , Células Progenitoras Endoteliais/metabolismo , Humanos , Hipolipemiantes/farmacologia , Inflamação/metabolismo , Lectinas/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Placa Aterosclerótica/tratamento farmacológico , Regulação para Cima/efeitos dos fármacos
3.
FASEB J ; 33(3): 3704-3717, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30514106

RESUMO

Nicotinamide phosphoribosyltransferase (NAMPT) is the rate-limiting enzyme in the NAD+ salvage pathway from nicotinamide. By controlling the biosynthesis of NAD+, NAMPT regulates the activity of NAD+-converting enzymes, such as CD38, poly-ADP-ribose polymerases, and sirtuins (SIRTs). SIRT6 is involved in the regulation of a wide number of metabolic processes. In this study, we investigated the ability of SIRT6 to regulate intracellular NAMPT activity and NAD(P)(H) levels. BxPC-3 cells and MCF-7 cells were engineered to overexpress a catalytically active or a catalytically inactive SIRT6 form or were engineered to silence endogenous SIRT6 expression. In SIRT6-overexpressing cells, NAD(H) levels were up-regulated, as a consequence of NAMPT activation. By immunopurification and incubation with recombinant SIRT6, NAMPT was found to be a direct substrate of SIRT6 deacetylation, with a mechanism that up-regulates NAMPT enzymatic activity. Extracellular NAMPT release was enhanced in SIRT6-silenced cells. Also glucose-6-phosphate dehydrogenase activity and NADPH levels were increased in SIRT6-overexpressing cells. Accordingly, increased SIRT6 levels reduced cancer cell susceptibility to H2O2-induced oxidative stress and to doxorubicin. Our data demonstrate that SIRT6 affects intracellular NAMPT activity, boosts NAD(P)(H) levels, and protects against oxidative stress. The use of SIRT6 inhibitors, together with agents inducing oxidative stress, may represent a promising treatment strategy in cancer.-Sociali, G., Grozio, A., Caffa, I., Schuster, S., Becherini, P., Damonte, P., Sturla, L., Fresia, C., Passalacqua, M., Mazzola, F., Raffaelli, N., Garten, A., Kiess, W., Cea, M., Nencioni, A., Bruzzone, S. SIRT6 deacetylase activity regulates NAMPT activity and NAD(P)(H) pools in cancer cells.


Assuntos
Citocinas/metabolismo , NADP/metabolismo , Neoplasias/metabolismo , Nicotinamida Fosforribosiltransferase/metabolismo , Sirtuínas/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Glucosefosfato Desidrogenase/metabolismo , Células HEK293 , Células Hep G2 , Humanos , Peróxido de Hidrogênio/farmacologia , Células MCF-7 , Neoplasias/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Poli(ADP-Ribose) Polimerases/metabolismo , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/fisiologia
4.
Leuk Res ; 69: 39-46, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29653431

RESUMO

NAMPT (Nicotinamide phosphoribosyltransferase) catalyses the rate-limiting step in the NAD biosynthesis from nicotinamide and thereby regulates the activity of NAD-dependent enzymes. Cancer cells are highly dependent on NAD for energy and DNA repair processes and are assumed to be more susceptible to an inhibition of NAD synthesis than non-transformed cells. We aimed to investigate whether or not inhibition of NAMPT with its specific inhibitor FK866 can sensitize leukemia cells for chemotherapeutic agents. NAMPT protein abundance, enzymatic activity and NAD concentrations were significantly higher in Jurkat and Molt-4 leukemia cell lines compared to normal peripheral blood mononuclear cells. Combination of etoposide and FK866 caused increased cell death in leukemia cell lines compared to etoposide alone. Etoposide decreased protein abundance of NAD-dependent deacetylases SIRTUIN1. After combining etoposide and FK866 treatment SIRTUIN2 was further decreased and accumulation and acetylation of the downstream target p53 was further enhanced in MOLT4 cells. Concomitantly, protein abundance of p21 and cleaved BAX was increased. Targeting NAMPT could be a novel therapeutic strategy to enhance the efficacy of chemotherapeutic agents such as etoposide against leukemia.


Assuntos
Citocinas/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Etoposídeo/farmacologia , Leucemia/tratamento farmacológico , Nicotinamida Fosforribosiltransferase/antagonistas & inibidores , Sirtuína 2/metabolismo , Inibidores da Topoisomerase II/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Leucemia/enzimologia , Leucemia/metabolismo , Transdução de Sinais
5.
Hepatology ; 67(2): 736-749, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28902427

RESUMO

The NLRP3 inflammasome, a caspase-1 activation platform, plays a key role in the modulation of liver inflammation and fibrosis. Here, we tested the hypothesis that interleukin 17 (IL-17) and tumor necrosis factor (TNF) are key cytokines involved in amplifying and perpetuating the liver damage and fibrosis resulting from NLRP3 activation. To address this hypothesis, gain-of-function Nlrp3A350V knock-in mice were bred onto il17a and Tnf knockout backgrounds allowing for constitutive Nlrp3 activation in myeloid derived cells in mice deficient in IL-17 or TNF. Livers of Nlrp3A350V knock-in mice exhibited severe liver inflammatory changes characterized by infiltration with neutrophils, increased expression of chemokine (C-X-C motif) ligand (CXCL) 1 and CXCL2 chemokines, activated inflammatory macrophages, and elevated levels of IL-17 and TNF. Mutants with ablation of il17a signal showed fewer neutrophils when compared to intact Nlrp3A350V mutants, but still significant inflammatory changes when compared to the nonmutant il17a knockout littermates. The severe inflammatory changes associated with mutant Nlrp3 were almost completely rescued by Tnf knockout in association with a marked decrease in circulating IL-1ß levels. Intact Nlrp3A350V mutants showed changes in liver fibrosis, as evidenced by morphometric quantitation of Sirius Red staining and increased mRNA levels of profibrotic genes, including connective tissue growth factor and tissue inhibitor of matrix metalloproteinase 1. Il17a lacking mutants exhibited amelioration of the aforementioned fibrosis, whereas Tnf-deficient mutants showed no signs of fibrosis when compared to littermate controls. Conclusion: Our study uncovers key roles for TNF and, to a lesser extent, IL-17 as mediators of liver inflammation and fibrosis induced by constitutive NLRP3 inflammasome activation in myeloid-derived cells. These findings may lead to therapeutic strategies aimed at halting the progression of liver injury and fibrogenesis in various liver pathogeneses driven by NLRP3 activation. (Hepatology 2018;67:736-749).


Assuntos
Hepatite/etiologia , Interleucina-17/fisiologia , Cirrose Hepática Experimental/etiologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/fisiologia , Fator de Necrose Tumoral alfa/fisiologia , Animais , Células Estreladas do Fígado/fisiologia , Macrófagos/fisiologia , Camundongos , Infiltração de Neutrófilos , Transdução de Sinais
6.
Lipids Health Dis ; 16(1): 191, 2017 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-28974242

RESUMO

BACKGROUND: Nicotinamide phosphoribosyltransferase (NAMPT) and nicotinamide adenine dinucleotide (NAD) levels are crucial for liver function. The saturated fatty acid palmitate and the unsaturated fatty acid oleate are the main free fatty acids in adipose tissue and human diet. We asked how these fatty acids affect cell survival, NAMPT and NAD levels in HepG2 cells and primary human hepatocytes. METHODS: HepG2 cells were stimulated with palmitate (0.5mM), oleate (1mM) or a combination of both (0.5mM/1mM) as well as nicotinamide mononucleotide (NMN) (0.5 mM) or the specific NAMPT inhibitor FK866 (10nM). Cell survival was measured by WST-1 assay and Annexin V/propidium iodide staining. NAD levels were determined by NAD/NADH Assay or HPLC. Protein and mRNA levels were analysed by Western blot analyses and qPCR, respectively. NAMPT enzyme activity was measured using radiolabelled 14C-nicotinamide. Lipids were stained by Oil red O staining. RESULTS: Palmitate significantly reduced cell survival and induced apoptosis at physiological doses. NAMPT activity and NAD levels significantly declined after 48h of palmitate. In addition, NAMPT mRNA expression was enhanced which was associated with increased NAMPT release into the supernatant, while intracellular NAMPT protein levels remained stable. Oleate alone did not influence cell viability and NAMPT activity but ameliorated the negative impact of palmitate on cell survival, NAMPT activity and NAD levels, as well as the increased NAMPT mRNA expression and secretion. NMN was able to normalize intracellular NAD levels but did not ameliorate cell viability after co-stimulation with palmitate. FK866, a specific NAMPT inhibitor did not influence lipid accumulation after oleate-treatment. CONCLUSIONS: Palmitate targets NAMPT activity with a consequent cellular depletion of NAD. Oleate protects from palmitate-induced apoptosis and variation of NAMPT and NAD levels. Palmitate-induced cell stress leads to an increase of NAMPT mRNA and accumulation in the supernatant. However, the proapoptotic action of palmitate seems not to be mediated by decreased NAD levels.


Assuntos
Citocinas/genética , Hepatócitos/efeitos dos fármacos , NAD/metabolismo , Nicotinamida Fosforribosiltransferase/genética , Ácido Oleico/farmacologia , Ácido Palmítico/farmacologia , Acrilamidas/farmacologia , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Citocinas/antagonistas & inibidores , Citocinas/metabolismo , Inibidores Enzimáticos/farmacologia , Expressão Gênica , Células Hep G2 , Hepatócitos/citologia , Hepatócitos/metabolismo , Humanos , NAD/antagonistas & inibidores , Mononucleotídeo de Nicotinamida/farmacologia , Nicotinamida Fosforribosiltransferase/antagonistas & inibidores , Nicotinamida Fosforribosiltransferase/metabolismo , Ácido Palmítico/antagonistas & inibidores , Piperidinas/farmacologia , Cultura Primária de Células , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
7.
Am J Pathol ; 187(10): 2232-2245, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28923202

RESUMO

Alcoholic liver disease is a major human health problem leading to significant morbidity and mortality in the United States and worldwide. Dietary fat plays an important role in alcoholic liver disease pathogenesis. Herein, we tested the hypothesis that a combination of ethanol and a diet rich in linoleic acid (LA) leads to the increased production of oxidized LA metabolites (OXLAMs), specifically 9- and 13-hydroxyoctadecadienoic acids (HODEs), which contribute to a hepatic proinflammatory response exacerbating liver injury. Mice were fed unsaturated (with a high LA content) or saturated fat diets (USF and SF, respectively) with or without ethanol for 10 days, followed by a single binge of ethanol. Compared to SF+ethanol, mice fed USF+ethanol had elevated plasma alanine transaminase levels, enhanced hepatic steatosis, oxidative stress, and inflammation. Plasma and liver levels of 9- and 13-HODEs were increased in response to USF+ethanol feeding. We demonstrated that primarily 9-HODE, but not 13-HODE, induced the expression of several proinflammatory cytokines in vitro in RAW264.7 macrophages. Finally, deficiency of arachidonate 15-lipoxygenase, a major enzyme involved in LA oxidation and OXLAM production, attenuated liver injury and inflammation caused by USF+ethanol feeding but had no effect on hepatic steatosis. This study demonstrates that OXLAM-mediated induction of a proinflammatory response in macrophages is one of the potential mechanisms underlying the progression from alcohol-induced steatosis to alcoholic steatohepatitis.


Assuntos
Gorduras na Dieta/efeitos adversos , Inflamação/patologia , Ácido Linoleico/efeitos adversos , Fígado/metabolismo , Fígado/patologia , Animais , Araquidonato 15-Lipoxigenase/metabolismo , Consumo Excessivo de Bebidas Alcoólicas , Composição Corporal , Citocinas/metabolismo , Modelos Animais de Doenças , Etanol , Ácidos Linoleicos/metabolismo , Ácidos Linoleicos Conjugados/metabolismo , Macrófagos/metabolismo , Metaboloma , Camundongos , Camundongos Endogâmicos C57BL , Oxirredução , Estresse Oxidativo , Células RAW 264.7
9.
Nutr Cancer ; 68(2): 342-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26943752

RESUMO

Patients with phosphatase and tensin homolog (PTEN) hamartoma tumor syndrome and germline mutations in PTEN frequently develop lipomatosis, for which there is no standard treatment. Rapamycin was shown to reduce the growth of lipoma cells with heterozygous PTEN deficiency in vitro, but concomitantly induced an upregulation of AKT phosphorylation. Since it was shown that resveratrol stabilizes PTEN, we asked whether co-incubation with resveratrol could suppress the rapamycin-induced AKT phosphorylation in PTEN-deficient lipoma cells. Resveratrol incubation resulted in decreased lipoma cell viability by inducing G1-phase cell cycle arrest and apoptosis. PTEN expression and AKT phosphorylation were not significantly changed, whereas p70S6 kinase (p70S6K) phosphorylation was reduced in PTEN-deficient lipoma cells after resveratrol incubation. Rapamycin/resveratrol co-incubation significantly decreased viability further at lower doses of resveratrol and resulted in decreased p70S6K phosphorylation compared to rapamycin incubation alone, suggesting that resveratrol potentiated the growth inhibitory effects of rapamycin by reducing p70S6K activation. Both viability and p70S6K phosphorylation of primary PTEN wild-type preadipocytes were less affected compared to PTEN-deficient lipoma cells by equimolar concentrations of resveratrol. These results support the concept of combining chemopreventive natural compounds with mammalian target of rapamycin (mTOR) inhibitors to increase the efficacy of chemotherapeutic drugs for patients suffering from overgrowth syndromes.


Assuntos
Lipoma/tratamento farmacológico , PTEN Fosfo-Hidrolase/metabolismo , Proteínas Quinases S6 Ribossômicas 70-kDa/antagonistas & inibidores , Sirolimo/farmacologia , Estilbenos/farmacologia , Adipócitos/efeitos dos fármacos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Humanos , Lipoma/metabolismo , Lipoma/patologia , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Resveratrol , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Sirolimo/administração & dosagem , Estilbenos/administração & dosagem
10.
Nat Rev Endocrinol ; 11(9): 535-46, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26215259

RESUMO

Nicotinamide phosphoribosyltransferase (NAMPT) is a regulator of the intracellular nicotinamide adenine dinucleotide (NAD) pool. NAD is an essential coenzyme involved in cellular redox reactions and is a substrate for NAD-dependent enzymes. In various metabolic disorders and during ageing, levels of NAD are decreased. Through its NAD-biosynthetic activity, NAMPT influences the activity of NAD-dependent enzymes, thereby regulating cellular metabolism. In addition to its enzymatic function, extracellular NAMPT (eNAMPT) has cytokine-like activity. Abnormal levels of eNAMPT are associated with various metabolic disorders. NAMPT is able to modulate processes involved in the pathogenesis of obesity and related disorders such as nonalcoholic fatty liver disease (NAFLD) and type 2 diabetes mellitus (T2DM) by influencing the oxidative stress response, apoptosis, lipid and glucose metabolism, inflammation and insulin resistance. NAMPT also has a crucial role in cancer cell metabolism, is often overexpressed in tumour tissues and is an experimental target for antitumour therapies. In this Review, we discuss current understanding of the functions of NAMPT and highlight progress made in identifying the physiological role of NAMPT and its relevance in various human diseases and conditions, such as obesity, NAFLD, T2DM, cancer and ageing.


Assuntos
Citocinas/genética , Citocinas/fisiologia , NAD/metabolismo , Nicotinamida Fosforribosiltransferase/genética , Nicotinamida Fosforribosiltransferase/fisiologia , Animais , Diabetes Mellitus Tipo 2/metabolismo , Humanos , Obesidade/enzimologia , Obesidade/genética
11.
Biochem Biophys Res Commun ; 458(2): 334-40, 2015 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-25656579

RESUMO

BACKGROUND: Nicotinamide phosphoribosyltransferase (NAMPT) is the key enzyme of the NAD salvage pathway starting from nicotinamide. Cancer cells have an increased demand for NAD due to their high proliferation and DNA repair rate. Consequently, NAMPT is considered as a putative target for anti-cancer therapies. There is evidence that AMP-activated protein kinase (AMPK) and mammalian target of rapamycin (mTOR) become dysregulated during the development of hepatocellular carcinoma (HCC). Here, we investigated the effects of NAMPT inhibition by its specific inhibitor FK866 on the viability of hepatocarcinoma cells and analyzed the effects of FK866 on the nutrient sensor AMPK and mTOR complex1 (mTORC1) signaling. RESULTS: FK866 markedly decreased NAMPT activity and NAD content in hepatocarcinoma cells (Huh7 cells, Hep3B cells) and led to delayed ATP reduction which was associated with increased cell death. These effects could be abrogated by administration of nicotinamide mononucleotide (NMN), the enzyme product of NAMPT. Our results demonstrated a dysregulation of the AMPK/mTOR pathway in hepatocarcinoma cells compared to non-cancerous hepatocytes with a higher expression of mTOR and a lower AMPKα activation in hepatocarcinoma cells. We found that NAMPT inhibition by FK866 significantly activated AMPKα and inhibited the activation of mTOR and its downstream targets p70S6 kinase and 4E-BP1 in hepatocarcinoma cells. Non-cancerous hepatocytes were less sensitive to FK866 and did not show changes in AMPK/mTOR signaling after FK866 treatment. CONCLUSION: Taken together, these findings reveal an important role of the NAMPT-mediated NAD salvage pathway in the energy homeostasis of hepatocarcinoma cells and suggest NAMPT inhibition as a potential treatment option for HCC.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Acrilamidas/farmacologia , Carcinoma Hepatocelular/metabolismo , Citocinas/antagonistas & inibidores , Citocinas/metabolismo , Neoplasias Hepáticas/metabolismo , Nicotinamida Fosforribosiltransferase/antagonistas & inibidores , Nicotinamida Fosforribosiltransferase/metabolismo , Piperidinas/farmacologia , Serina-Treonina Quinases TOR/metabolismo , Trifosfato de Adenosina/metabolismo , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Ativação Enzimática , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Transdução de Sinais/efeitos dos fármacos
12.
PLoS One ; 9(3): e91045, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24603648

RESUMO

Resveratrol is reported to possess chemotherapeutic properties in several cancers. In this study, we wanted to investigate the molecular mechanisms of resveratrol-induced cell cycle arrest and apoptosis as well as the impact of resveratrol on NAMPT and SIRT1 protein function and asked whether there are differences in hepatocarcinoma cells (HepG2, Hep3B cells) and non-cancerous primary human hepatocytes. We found a lower basal NAMPT mRNA and protein expression in hepatocarcinoma cells compared to primary hepatocytes. In contrast, SIRT1 was significantly higher expressed in hepatocarcinoma cells than in primary hepatocytes. Resveratrol induced cell cycle arrest in the S- and G2/M- phase and apoptosis was mediated by activation of p53 and caspase-3 in HepG2 cells. In contrast to primary hepatocytes, resveratrol treated HepG2 cells showed a reduction of NAMPT enzymatic activity and increased p53 acetylation (K382). Resveratrol induced NAMPT release from HepG2 cells which was associated with increased NAMPT mRNA expression. This effect was absent in primary hepatocytes where resveratrol was shown to function as NAMPT and SIRT1 activator. SIRT1 inhibition by EX527 resembled resveratrol effects on HepG2 cells. Furthermore, a SIRT1 overexpression significantly decreased both p53 hyperacetylation and resveratrol-induced NAMPT release as well as S-phase arrest in HepG2 cells. We could show that NAMPT and SIRT1 are differentially regulated by resveratrol in hepatocarcinoma cells and primary hepatocytes and that resveratrol did not act as a SIRT1 activator in hepatocarcinoma cells.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Citocinas/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Nicotinamida Fosforribosiltransferase/genética , RNA Mensageiro/genética , Sirtuína 1/genética , Estilbenos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Citocinas/metabolismo , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Nicotinamida Fosforribosiltransferase/metabolismo , Especificidade de Órgãos , Cultura Primária de Células , RNA Mensageiro/metabolismo , Resveratrol , Pontos de Checagem da Fase S do Ciclo Celular/efeitos dos fármacos , Transdução de Sinais , Sirtuína 1/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
13.
Pediatr Res ; 75(4): 527-34, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24366516

RESUMO

BACKGROUND: Phosphatase and tensin homolog (PTEN) hamartoma tumor syndrome (PHTS) is caused by germ line mutations in the PTEN gene. Symptoms include cancer predisposition, immune deviations, and lipomas/lipomatosis. No causal standard therapy is available. We describe a therapeutic attempt with the mammalian target of rapamycin (mTOR) inhibitor sirolimus for a PHTS patient suffering from thymus hyperplasia and lipomatosis. We furthermore assessed the in vitro effects of sirolimus and other inhibitors on lipoma cells of the patient. METHODS: The patient underwent clinical and blood examinations and whole-body magnetic resonance imaging to assess tumor sizes. Lipoma cells of the patient were incubated with inhibitors of the phosphoinositide-3-kinase (PI3K)/AKT/mTOR signaling pathway to analyze the effects on proliferation, adipocyte differentiation, and survival in vitro. RESULTS: Sirolimus treatment improved somatic growth and reduced thymus volume. These effects diminished over the treatment period of 19 mo. Sirolimus decreased lipoma cell proliferation and adipocyte differentiation in vitro but did not cause apoptosis. PI3K and AKT inhibitors induced apoptosis significantly. CONCLUSION: Sirolimus treatment led to an improvement of the patient's clinical status and a transient reduction of the thymus. Our in vitro findings point to PI3K and AKT inhibitors as potential treatment options for patients with severe forms of PHTS.


Assuntos
Síndrome do Hamartoma Múltiplo/tratamento farmacológico , PTEN Fosfo-Hidrolase/genética , Sirolimo/uso terapêutico , Pré-Escolar , Síndrome do Hamartoma Múltiplo/genética , Humanos , Técnicas In Vitro , Lactente , Recém-Nascido
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