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1.
EMBO J ; 40(6): e104296, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33459422

RESUMO

The IκB kinase (IKK)-NF-κB pathway is activated as part of the DNA damage response and controls both inflammation and resistance to apoptosis. How these distinct functions are achieved remained unknown. We demonstrate here that DNA double-strand breaks elicit two subsequent phases of NF-κB activation in vivo and in vitro, which are mechanistically and functionally distinct. RNA-sequencing reveals that the first-phase controls anti-apoptotic gene expression, while the second drives expression of senescence-associated secretory phenotype (SASP) genes. The rapidly activated first phase is driven by the ATM-PARP1-TRAF6-IKK cascade, which triggers proteasomal destruction of inhibitory IκBα, and is terminated through IκBα re-expression from the NFKBIA gene. The second phase, which is activated days later in senescent cells, is on the other hand independent of IKK and the proteasome. An altered phosphorylation status of NF-κB family member p65/RelA, in part mediated by GSK3ß, results in transcriptional silencing of NFKBIA and IKK-independent, constitutive activation of NF-κB in senescence. Collectively, our study reveals a novel physiological mechanism of NF-κB activation with important implications for genotoxic cancer treatment.


Assuntos
Senescência Celular/fisiologia , Quinase I-kappa B/metabolismo , Inibidor de NF-kappaB alfa/biossíntese , Fator de Transcrição RelA/metabolismo , Transcrição Gênica/genética , Animais , Apoptose/genética , Linhagem Celular , Proliferação de Células/genética , Quebras de DNA de Cadeia Dupla , Reparo do DNA/genética , Feminino , Inativação Gênica/fisiologia , Glicogênio Sintase Quinase 3 beta/metabolismo , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Inibidor de NF-kappaB alfa/genética , Fosforilação , Complexo de Endopeptidases do Proteassoma/metabolismo
2.
Nature ; 553(7686): 96-100, 2018 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-29258294

RESUMO

Cellular senescence is a stress-responsive cell-cycle arrest program that terminates the further expansion of (pre-)malignant cells. Key signalling components of the senescence machinery, such as p16INK4a, p21CIP1 and p53, as well as trimethylation of lysine 9 at histone H3 (H3K9me3), also operate as critical regulators of stem-cell functions (which are collectively termed 'stemness'). In cancer cells, a gain of stemness may have profound implications for tumour aggressiveness and clinical outcome. Here we investigated whether chemotherapy-induced senescence could change stem-cell-related properties of malignant cells. Gene expression and functional analyses comparing senescent and non-senescent B-cell lymphomas from Eµ-Myc transgenic mice revealed substantial upregulation of an adult tissue stem-cell signature, activated Wnt signalling, and distinct stem-cell markers in senescence. Using genetically switchable models of senescence targeting H3K9me3 or p53 to mimic spontaneous escape from the arrested condition, we found that cells released from senescence re-entered the cell cycle with strongly enhanced and Wnt-dependent clonogenic growth potential compared to virtually identical populations that had been equally exposed to chemotherapy but had never been senescent. In vivo, these previously senescent cells presented with a much higher tumour initiation potential. Notably, the temporary enforcement of senescence in p53-regulatable models of acute lymphoblastic leukaemia and acute myeloid leukaemia was found to reprogram non-stem bulk leukaemia cells into self-renewing, leukaemia-initiating stem cells. Our data, which are further supported by consistent results in human cancer cell lines and primary samples of human haematological malignancies, reveal that senescence-associated stemness is an unexpected, cell-autonomous feature that exerts its detrimental, highly aggressive growth potential upon escape from cell-cycle blockade, and is enriched in relapse tumours. These findings have profound implications for cancer therapy, and provide new mechanistic insights into the plasticity of cancer cells.


Assuntos
Reprogramação Celular , Senescência Celular , Linfoma de Células B/patologia , Células-Tronco Neoplásicas/patologia , Animais , Biomarcadores/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Reprogramação Celular/efeitos dos fármacos , Senescência Celular/efeitos dos fármacos , Senescência Celular/genética , Células Clonais/efeitos dos fármacos , Células Clonais/patologia , Feminino , Humanos , Linfoma de Células B/tratamento farmacológico , Linfoma de Células B/genética , Masculino , Camundongos , Camundongos Transgênicos , Células-Tronco Neoplásicas/efeitos dos fármacos , Fenótipo , Via de Sinalização Wnt/efeitos dos fármacos
3.
J Immunol ; 206(6): 1228-1239, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33536256

RESUMO

Ataxia-telangiectasia mutated (ATM) kinase is a master regulator of the DNA damage response, and loss of ATM leads to primary immunodeficiency and greatly increased risk for lymphoid malignancies. The FATC domain is conserved in phosphatidylinositol-3-kinase-related protein kinases (PIKKs). Truncation mutation in the FATC domain (R3047X) selectively compromised reactive oxygen species-induced ATM activation in cell-free assays. In this article, we show that in mouse models, knock-in ATM-R3057X mutation (Atm⁠ RX ⁠, corresponding to R3047X in human ATM) severely compromises ATM protein stability and causes T cell developmental defects, B cell Ig class-switch recombination defects, and infertility resembling ATM-null. The residual ATM-R3057X protein retains minimal yet functional measurable DNA damage-induced checkpoint activation and significantly delays lymphomagenesis in Atm⁠ RX/RX ⁠ mice compared with Atm⁠ -/- ⁠. Together, these results support a physiological role of the FATC domain in ATM protein stability and show that the presence of minimal residual ATM-R3057X protein can prevent growth retardation and delay tumorigenesis without restoring lymphocyte development and fertility.


Assuntos
Linfócitos/imunologia , Linfoma/genética , Domínios Proteicos/genética , Animais , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Carcinogênese/genética , Carcinogênese/imunologia , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Códon sem Sentido , Modelos Animais de Doenças , Técnicas de Introdução de Genes , Humanos , Linfócitos/patologia , Linfoma/imunologia , Linfoma/patologia , Masculino , Camundongos , Camundongos Knockout , Estabilidade Proteica , Recombinação V(D)J/genética , Recombinação V(D)J/imunologia
4.
Arch Pharm (Weinheim) ; 354(5): e2000416, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33491801

RESUMO

Pinus nigra Arn. bark extracts from Mokra gora (MG) and Tara mountains were analyzed with regard to their polyphenolic profile and antioxidative and antiproliferative activity. The ethanol extract from MG showed the highest phenolic, flavonoid, tannin, and proanthocyanidin content when compared with the acetone and methanol extracts from both sites. The same extract exhibited the highest ABTS (2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt) and ferric reducing antioxidant power (FRAP) radical scavenging ability and total antioxidant activity (TAA). On the basis of high-performance liquid chromatography analysis, catechin, caffeic, syringic, p-coumaric, and ferulic acids were predominantly present in the MG extracts. The ethanol extract from MG was rich in syringic acid, epicatechin and its derivatives, and ferulic acid and its derivatives. The bark extracts also exerted a high cytotoxic bioactivity against all evaluated cell lines (HeLa, MCF7, HT-29, and MRC-5). The antiproliferative activity of P. nigra bark is probably related to the ferulic acid content and its synergistic activity to caffeic acid and taxifolin. The antioxidative role of the presented phenols was confirmed through the obtained significant linear correlation between the total phenolic content and DPPH (r = .934) as well as the FRAP% of the extracts (r = .948). Also, the TAA significantly depended on the proanthocyanidins (r = .902) and tannin contents (r = .914). The composition of the presented compounds could be related to promising antioxidant and antiproliferative efficacy of MG bark.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/farmacologia , Compostos Fitoquímicos/farmacologia , Pinus/química , Extratos Vegetais/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antioxidantes/química , Antioxidantes/isolamento & purificação , Compostos de Bifenilo/antagonistas & inibidores , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Compostos Fitoquímicos/química , Compostos Fitoquímicos/isolamento & purificação , Picratos/antagonistas & inibidores , Casca de Planta/química , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Relação Estrutura-Atividade
5.
Blood ; 129(1): 71-81, 2017 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-27733358

RESUMO

Classical Hodgkin lymphoma (cHL), although originating from B cells, is characterized by the virtual lack of gene products whose expression constitutes the B-cell phenotype. Epigenetic repression of B-cell-specific genes via promoter hypermethylation and histone deacetylation as well as compromised expression of B-cell-committed transcription factors were previously reported to contribute to the lost B-cell phenotype in cHL. Restoring the B-cell phenotype may not only correct a central malignant property, but it may also render cHL susceptible to clinically established antibody therapies targeting B-cell surface receptors or small compounds interfering with B-cell receptor signaling. We conducted a high-throughput pharmacological screening based on >28 000 compounds in cHL cell lines carrying a CD19 reporter to identify drugs that promote reexpression of the B-cell phenotype. Three chemicals were retrieved that robustly enhanced CD19 transcription. Subsequent chromatin immunoprecipitation-based analyses indicated that action of 2 of these compounds was associated with lowered levels of the transcriptionally repressive lysine 9-trimethylated histone H3 mark at the CD19 promoter. Moreover, the antileukemia agents all-trans retinoic acid and arsenic trioxide (ATO) were found to reconstitute the silenced B-cell transcriptional program and reduce viability of cHL cell lines. When applied in combination with a screening-identified chemical, ATO evoked reexpression of the CD20 antigen, which could be further therapeutically exploited by enabling CD20 antibody-mediated apoptosis of cHL cells. Furthermore, restoration of the B-cell phenotype also rendered cHL cells susceptible to the B-cell non-Hodgkin lymphoma-tailored small-compound inhibitors ibrutinib and idelalisib. In essence, we report here a conceptually novel, redifferentiation-based treatment strategy for cHL.


Assuntos
Antineoplásicos/farmacologia , Linfócitos B/imunologia , Diferenciação Celular/efeitos dos fármacos , Doença de Hodgkin/imunologia , Transcriptoma/efeitos dos fármacos , Antígenos CD19/imunologia , Antígenos CD20/imunologia , Linfócitos B/efeitos dos fármacos , Imunoprecipitação da Cromatina , Citometria de Fluxo , Ensaios de Triagem em Larga Escala , Humanos , Fenótipo , Reação em Cadeia da Polimerase , Células Tumorais Cultivadas
6.
Nature ; 501(7467): 421-5, 2013 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-23945590

RESUMO

Activated oncogenes and anticancer chemotherapy induce cellular senescence, a terminal growth arrest of viable cells characterized by S-phase entry-blocking histone 3 lysine 9 trimethylation (H3K9me3). Although therapy-induced senescence (TIS) improves long-term outcomes, potentially harmful properties of senescent tumour cells make their quantitative elimination a therapeutic priority. Here we use the Eµ-myc transgenic mouse lymphoma model in which TIS depends on the H3K9 histone methyltransferase Suv39h1 to show the mechanism and therapeutic exploitation of senescence-related metabolic reprogramming in vitro and in vivo. After senescence-inducing chemotherapy, TIS-competent lymphomas but not TIS-incompetent Suv39h1(-) lymphomas show increased glucose utilization and much higher ATP production. We demonstrate that this is linked to massive proteotoxic stress, which is a consequence of the senescence-associated secretory phenotype (SASP) described previously. SASP-producing TIS cells exhibited endoplasmic reticulum stress, an unfolded protein response (UPR), and increased ubiquitination, thereby targeting toxic proteins for autophagy in an acutely energy-consuming fashion. Accordingly, TIS lymphomas, unlike senescence models that lack a strong SASP response, were more sensitive to blocking glucose utilization or autophagy, which led to their selective elimination through caspase-12- and caspase-3-mediated endoplasmic-reticulum-related apoptosis. Consequently, pharmacological targeting of these metabolic demands on TIS induction in vivo prompted tumour regression and improved treatment outcomes further. These findings unveil the hypercatabolic nature of TIS that is therapeutically exploitable by synthetic lethal metabolic targeting.


Assuntos
Autofagia , Senescência Celular , Glucose/metabolismo , Linfoma de Células B/tratamento farmacológico , Linfoma de Células B/metabolismo , Animais , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Caspase 12/metabolismo , Caspase 3/metabolismo , Senescência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Estresse do Retículo Endoplasmático , Feminino , Linfoma de Células B/genética , Linfoma de Células B/patologia , Masculino , Camundongos , Camundongos Transgênicos , Proteólise , Estresse Fisiológico , Taxa de Sobrevida
7.
Genes Dev ; 25(20): 2137-46, 2011 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-21979374

RESUMO

In malignancies, enhanced nuclear factor-κB (NF-κB) activity is largely viewed as an oncogenic property that also confers resistance to chemotherapy. Recently, NF-κB has been postulated to participate in a senescence-associated and possibly senescence-reinforcing cytokine response, thereby suggesting a tumor-restraining role for NF-κB. Using a mouse lymphoma model and analyzing transcriptome and clinical data from lymphoma patients, we show here that therapy-induced senescence presents with and depends on active NF-κB signaling, whereas NF-κB simultaneously promotes resistance to apoptosis. Further characterization and genetic engineering of primary mouse lymphomas according to distinct NF-κB-related oncogenic networks reminiscent of diffuse large B-cell lymphoma (DLBCL) subtypes guided us to identify Bcl2-overexpressing germinal center B-cell-like (GCB) DLBCL as a clinically relevant subgroup with significantly superior outcome when NF-κB is hyperactive. Our data illustrate the power of cross-species investigations to functionally test genetic mechanisms in transgenic mouse tumors that recapitulate distinct features of the corresponding human entity, and to ultimately use the mouse model-derived genetic information to redefine novel, clinically relevant patient subcohorts.


Assuntos
Antineoplásicos/farmacologia , Senescência Celular/efeitos dos fármacos , Senescência Celular/fisiologia , NF-kappa B/metabolismo , Animais , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Linfoma de Células B/tratamento farmacológico , Linfoma de Células B/metabolismo , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma não Hodgkin/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Transdução de Sinais
8.
Immunol Cell Biol ; 95(3): 261-271, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27649781

RESUMO

Signaling through the canonical nuclear factor-κB (NF-κB) pathway is critical for the generation and maintenance of mature B cells and for antigen-dependent B-cell activation. c-REL (rel) and RELA (rela) are the downstream transcriptional activators of the canonical NF-κB pathway. Studies of B cells derived from constitutional rel knockout mice and chimeric mice repopulated with rela-/- fetal liver cells provided evidence that the subunits can have distinct roles during B-cell development. However, the B cell-intrinsic functions of c-REL and RELA during B-cell generation and antigen-dependent B-cell activation have not been determined in vivo. To clarify this issue, we crossed mice with conditional rel and rela alleles individually or in combination to mice that express Cre-recombinase in B cells. We here report that, whereas single deletion of rel or rela did not impair mature B-cell generation and maintenance, their simultaneous deletion led to a dramatic reduction of follicular and marginal zone B cells. Upon T cell-dependent immunization, B cell-specific deletion of the c-REL subunit alone abrogated the formation of germinal centers (GCs), whereas rela deletion did not affect GC formation. T-independent responses were strongly impaired in mice with B cell-specific deletion of rel, and only modestly in mice with RELA-deficient B cells. Our findings identify differential requirements for the canonical NF-κB subunits c-REL and RELA at distinct stages of mature B-cell development. The subunits are jointly required for the generation of mature B cells. During antigen-dependent B-cell activation, c-REL is the critical subunit required for the initiation of the GC reaction and for optimal T-independent antibody responses, with RELA being largely dispensable at this stage.


Assuntos
Linfócitos B/citologia , Linfócitos B/metabolismo , Ativação Linfocitária/imunologia , Proteínas Proto-Oncogênicas c-rel/metabolismo , Fator de Transcrição RelA/metabolismo , Animais , Formação de Anticorpos/imunologia , Fator Ativador de Células B/metabolismo , Células da Medula Óssea/citologia , Diferenciação Celular , Sobrevivência Celular , Deleção de Genes , Centro Germinativo/citologia , Integrases/metabolismo , Camundongos Endogâmicos C57BL , Baço/citologia
9.
Biochem J ; 457(3): 401-13, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24175631

RESUMO

The transcription factor NF-κB (nuclear factor κB) serves to up-regulate gene expression in response to precarious signals such as the pro-inflammatory cytokines TNF (tumour necrosis factor) and IL-1 (interleukin 1). In the present study we show that stimulation of cells with TNF or IL-1 results in a profound conformational switch of the NF-κB subunit p65, as revealed by limited proteolysis assays. We also describe the identification of a conformation-specific monoclonal antibody that preferentially immunoprecipitates the inducibly refolded p65 protein. The cytokine-triggered reconfiguration of p65 mainly occurs for p65 contained in the nuclear fraction. Phosphorylations serve as the central driving force for the inducible reconfiguration of p65. Accordingly, mutation of single phosphorylation sites in the C-terminal transactivation domain led to large conformational changes which result in strongly decreased ubiquitination and also in differential protein-protein interactions. Induced conformational changes of p65 thus increase the intramolecular flexibility and therefore expand and specify the repertoire of possible protein-protein interactions. Constitutively bound chaperones of the Hsp (heat-shock protein)/Hsc70 (heat-shock cognate protein, 73 kDa) family are not important for the cytokine-induced conformational switch, but rather control the fidelity of protein rearrangement. Accordingly, pharmacological inhibition of Hsp/Hsc70 interferes with p65-triggered gene expression.


Assuntos
Núcleo Celular/metabolismo , Citocinas/metabolismo , Processamento de Proteína Pós-Traducional , Redobramento de Proteína , Fator de Transcrição RelA/metabolismo , Regulação para Cima , Substituição de Aminoácidos , Animais , Linhagem Celular , Células Cultivadas , Embrião de Mamíferos/citologia , Proteínas de Choque Térmico HSC70/antagonistas & inibidores , Proteínas de Choque Térmico HSC70/química , Proteínas de Choque Térmico HSC70/genética , Proteínas de Choque Térmico HSC70/metabolismo , Humanos , Camundongos , Camundongos Knockout , Proteínas Mutantes/química , Proteínas Mutantes/metabolismo , Fosforilação , Domínios e Motivos de Interação entre Proteínas , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Fator de Transcrição RelA/química , Fator de Transcrição RelA/genética , Ubiquitinação
10.
Nucleic Acids Res ; 41(11): 5731-45, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23620283

RESUMO

Differentiation of skeletal muscle cells is accompanied by drastic changes in gene expression programs that depend on activation and repression of genes at defined time points. Here we identify the serine/threonine kinase homeodomain-interacting protein kinase 2 (HIPK2) as a corepressor that inhibits myocyte enhancer factor 2 (MEF2)-dependent gene expression in undifferentiated myoblasts. Downregulation of HIPK2 expression by shRNAs results in elevated expression of muscle-specific genes, whereas overexpression of the kinase dampens transcription of these genes. HIPK2 is constitutively associated with a multi-protein complex containing histone deacetylase (HDAC)3 and HDAC4 that serves to silence MEF2C-dependent transcription in undifferentiated myoblasts. HIPK2 interferes with gene expression on phosphorylation and HDAC3-dependent deacetylation of MEF2C. Ongoing muscle differentiation is accompanied by elevated caspase activity, which results in caspase-mediated cleavage of HIPK2 following aspartic acids 916 and 977 and the generation of a C-terminally truncated HIPK2 protein. The short form of the kinase loses its affinity to the repressive multi-protein complex and its ability to bind HDAC3 and HDAC4, thus alleviating its repressive function for expression of muscle genes. This study identifies HIPK2 as a further protein that determines the threshold and kinetics of gene expression in proliferating myoblasts and during the initial steps of myogenesis.


Assuntos
Proteínas de Transporte/metabolismo , Caspases/metabolismo , Proteínas Correpressoras/metabolismo , Desenvolvimento Muscular/genética , Mioblastos Esqueléticos/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Acetilação , Animais , Ácido Aspártico/análise , Proteínas de Transporte/química , Diferenciação Celular/genética , Linhagem Celular , Proteínas Correpressoras/química , Histona Desacetilases/metabolismo , Humanos , Fatores de Transcrição MEF2 , Camundongos , Mioblastos Esqueléticos/enzimologia , Fatores de Regulação Miogênica/metabolismo , Proteínas Serina-Treonina Quinases/química , Transcrição Gênica
11.
Nutrients ; 16(8)2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38674916

RESUMO

A sedentary lifestyle associated with unregulated diets rich in high-calorie foods have contributed to the great prevalence of metabolic dysfunction-associated steatotic liver disease (MASLD) latterly, with up to 60% in the high-risk population and 25% in the general population. The absence of specific pharmacological strategies for this syndrome represents one of the major problems in the management of MASLD patients. Lifestyle interventions and adherence to a healthy diet are the main cornerstones of current therapies. The identification of nutraceuticals useful in the treatment of MASLD appears to be one of the most promising strategies for the development of new effective and safe treatments for this disease. The onion, one of the most widely studied foods in the field of nutraceuticals, serves as an inexhaustible reservoir of potent compounds with various beneficial effects. The following preliminary study analyzes, mediating in silico studies, the iteration of a library of typical onion compounds with 3-hydroxy-3-methylglutaryl-coenzyme A reductase, liver receptors X α and ß, as well as peroxisome proliferator-activated receptors α and γ. In this study, for the first time promising smart molecules from the onion that could have a beneficial action in MASLD patients were identified.


Assuntos
Simulação de Acoplamento Molecular , Cebolas , Polifenóis , Cebolas/química , Polifenóis/farmacologia , Humanos , Ligantes , Suplementos Nutricionais , Hidroximetilglutaril-CoA Redutases/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo
12.
Nutrients ; 16(12)2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38931182

RESUMO

Hyperlipidaemia is a recognised risk factor for cardiovascular disease. In this study, the antihyperlipidaemic properties of spirulina (Arthrospira platensis, strain S2 from Serbia) were tested in adult Wistar rats before and after induction of hypercholesterolaemia by a high-fat diet (HFD) to compare the preventive with the curative effect. Total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), alanine transaminase (ALT) and aspartate transaminase (AST) levels were measured in the blood samples. The chemical composition (lipids, proteins and cholesterol) and the content of bile acids in the faeces of the animals were also analysed. Feeding rats with an atherogenic diet for 10 weeks led to the successful development of hyperlipidaemia, as serum TC and LDL-C levels as well as lipids, cholesterol and bile acids in the animals' faeces were significantly increased. Pre- and post-treatment with spirulina led to a reduction in serum LDL, TC and ALT levels. Administration of spirulina resulted in both a significant increase in primary bile acids excretion and a decrease in bile acids metabolism, with pre-treatment being more effective than post-treatment in some cases. These results suggest that increased excretion of bile acids as well as an effect on the gut microbiota may be the mechanism responsible for the anti-hyperlipidaemic activity of the tested spirulina strain.


Assuntos
Ácidos e Sais Biliares , Dieta Hiperlipídica , Fezes , Hipercolesterolemia , Ratos Wistar , Spirulina , Animais , Dieta Hiperlipídica/efeitos adversos , Hipercolesterolemia/etiologia , Ácidos e Sais Biliares/metabolismo , Masculino , Fezes/microbiologia , Fezes/química , Ratos , Colesterol/sangue , LDL-Colesterol/sangue , Probióticos/farmacologia , Aspartato Aminotransferases/sangue , Alanina Transaminase/sangue , HDL-Colesterol/sangue , Lipídeos/sangue , Modelos Animais de Doenças
13.
Int J Environ Health Res ; 23(4): 296-310, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23067248

RESUMO

The occurrence of pharmaceutical residues in the environment has become a subject of growing concern. Due to the constant input of the emerging contaminants in the surface water via wastewater which leads to the long-term adverse effects on the aquatic and terrestrial organisms, special attention is being paid to their presence in the aquatic environment. Most of the emerging substances, especially pharmaceuticals, could not be completely removed using the wastewater treatment. Pharmaceuticals are usually water soluble and poorly degradable. They can pass through all natural filtrations and then reach the groundwater and, finally, the drinking water. The trace levels of antibiotics could have a negative impact on the environment and public health because of their inherent bioactivity. This article is an overview of the presence of the antibiotic residual concentrations, methods and levels of detection and possible risks to both health and environment.


Assuntos
Antibacterianos/análise , Água Subterrânea/química , Águas Residuárias/química , Antibacterianos/química , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Monitoramento Ambiental , Espectrometria de Massas , Medição de Risco , Rios/química , Purificação da Água
14.
Environ Sci Pollut Res Int ; 30(10): 25119-25140, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34741734

RESUMO

Humans are exposed to the variety of emerging environmental pollutant in everyday life. The special concern is paid to endocrine disrupting chemicals especially to triclosan which could interfere with normal hormonal functions. Triclosan could be found in numerous commercial products such as mouthwashes, toothpastes and disinfectants due to its antibacterial and antifungal effects. Considering the excessive use and disposal, wastewaters are recognized as the main source of triclosan in the aquatic environment. As a result of the incomplete removal, triclosan residues reach surface water and even groundwater. Triclosan has potential to accumulate in sediment and aquatic organisms. Therefore, the detectable concentrations of triclosan in various environmental and biological matrices emerged concerns about the potential toxicity. Triclosan impairs thyroid homeostasis and could be associated with neurodevelopment impairment, metabolic disorders, cardiotoxicity and the increased cancer risk. The growing resistance of the vast groups of bacteria, the evidenced toxicity on different aquatic organisms, its adverse health effects observed in vitro, in vivo as well as the available epidemiological studies suggest that further efforts to monitor triclosan toxicity at environmental levels are necessary. The safety precaution measures and full commitment to proper legislation in compliance with the environmental protection are needed in order to obtain triclosan good ecological status. This paper is an overview of the possible negative triclosan effects on human health. Sources of exposure to triclosan, methods and levels of detection in aquatic environment are also discussed.


Assuntos
Desinfetantes , Triclosan , Poluentes Químicos da Água , Humanos , Triclosan/análise , Risco , Desinfetantes/farmacologia , Antifúngicos/farmacologia , Organismos Aquáticos , Avaliação de Resultados em Cuidados de Saúde , Poluentes Químicos da Água/análise
15.
CNS Neurosci Ther ; 29 Suppl 1: 43-58, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36601680

RESUMO

The gut microbiota-brain axis has been recognized as a network of connections that provides communication between the gut microflora and both central and autonomic nervous system. The gut microbiota alteration has been targeted for therapy in various neurodegenerative and psychiatric disbalances. Psychobiotics are probiotics that contribute beneficially to the brain function and the host mental health as a result of an interaction with the commensal gut bacteria, although their mechanism of action has not been completely revealed. In this state-of-art review, the findings about the potential therapeutic effects of the psychobiotics alone or in combination with conventional medicine in the treatment of neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease, as well as in some psychiatric diseases like depression, schizophrenia, and bipolar disorder, have been summarized. The evidence of the psychobiotics therapeutic outcomes obtained in preclinical and clinical trials have been given respectively for the observed neurodegenerative and psychiatric disorders.


Assuntos
Microbioma Gastrointestinal , Microbiota , Doenças Neurodegenerativas , Doença de Parkinson , Humanos , Encéfalo , Microbiota/fisiologia , Microbioma Gastrointestinal/fisiologia , Doenças Neurodegenerativas/terapia
16.
World J Diabetes ; 14(6): 705-723, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37383596

RESUMO

The number of people diagnosed with diabetes continues to increase, especially among younger populations. Apart from genetic predisposition and lifestyle, there is increasing scientific and public concern that environmental agents may also contribute to diabetes. Food contamination by chemical substances that originate from packaging materials, or are the result of chemical reactions during food processing, is generally recognized as a worldwide problem with potential health hazards. Phthalates, bisphenol A (BPA) and acrylamide (AA) have been the focus of attention in recent years, due to the numerous adverse health effects associated with their exposure. This paper summarizes the available data about the association between phthalates, BPA and AA exposure and diabetes. Although their mechanism of action has not been fully clarified, in vitro, in vivo and epidemiological studies have made significant progress toward identifying the potential roles of phthalates, BPA and AA in diabetes development and progression. These chemicals interfere with multiple signaling pathways involved in glucose and lipid homeostasis and can aggravate the symptoms of diabetes. Especially concerning are the effects of exposure during early stages and the gestational period. Well-designed prospective studies are needed in order to better establish prevention strategies against the harmful effects of these food contaminants.

17.
Clin Chim Acta ; 540: 117225, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36627009

RESUMO

BACKGROUND-AIM: Phthalates are known as endocrine disrupting chemicals which are present in wide-range of products. The objective of the study was to investigate whether phthalate exposure may attribute to the metabolic syndrome development in women with polycystic ovary syndrome (PCOS). METHOD: The cross-sectional study involved 60 women in reproductive age with confirmed PCOS. Anthropometric and biochemical measurements were examined together with detected levels of ten phthalate metabolites measured by GC-MS in morning urine samples. RESULTS: In this study at least one phthalate metabolite was detected in 51.7% of samples. Total phthalate metabolites urine concentrations were positively associated with BMI, waist circumference, waist-to-height-ratio (WtHR), leptin serum levels as well as lipid accumulation product (LAP) and visceral adiposity index (VAI). Mono-methyl-phthalate (MMP) levels was significantly correlated with WtHR, LAP and VAI. Additionally, total phthalate metabolites levels were significantly linked with fasting plasma glucose and HOMA index, whereas MMP concentrations were associated with fasting plasma glucose and insulin levels. Total cholesterol (TC) level was statistically significantly higher among PCOS women with detected phthalate metabolites compared to those without phthalates. The sum of all phthalates was correlated with LDL and triglyceride levels as well as TC/HDL. MMP concentrations were linked positively with TC, LDL and triglyceride levels as well as with TC/HDL. It is noteworthy that MMP concentrations were positively associated with testosterone serum levels while the total phthalate metabolites concentrations were also linked but with moderate significance. CONCLUSIONS: The increased phthalate metabolites concentrations may interfere with obesity, glucose and lipid impairment in PCOS women. Additionally, testosterone serum levels can be disrupted by MMP.


Assuntos
Resistência à Insulina , Síndrome Metabólica , Síndrome do Ovário Policístico , Humanos , Feminino , Síndrome do Ovário Policístico/metabolismo , Glicemia/metabolismo , Estudos Transversais , Obesidade Abdominal , HDL-Colesterol , Triglicerídeos , Testosterona , Índice de Massa Corporal , Síndrome Metabólica/complicações , Insulina
18.
EMBO Mol Med ; 15(9): e16431, 2023 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-37485814

RESUMO

The DNA damage response (DDR) acts as a barrier to malignant transformation and is often impaired during tumorigenesis. Exploiting the impaired DDR can be a promising therapeutic strategy; however, the mechanisms of inactivation and corresponding biomarkers are incompletely understood. Starting from an unbiased screening approach, we identified the SMC5-SMC6 Complex Localization Factor 2 (SLF2) as a regulator of the DDR and biomarker for a B-cell lymphoma (BCL) patient subgroup with an adverse prognosis. SLF2-deficiency leads to loss of DDR factors including Claspin (CLSPN) and consequently impairs CHK1 activation. In line with this mechanism, genetic deletion of Slf2 drives lymphomagenesis in vivo. Tumor cells lacking SLF2 are characterized by a high level of DNA damage, which leads to alterations of the post-translational SUMOylation pathway as a safeguard. The resulting co-dependency confers synthetic lethality to a clinically applicable SUMOylation inhibitor (SUMOi), and inhibitors of the DDR pathway act highly synergistic with SUMOi. Together, our results identify SLF2 as a DDR regulator and reveal co-targeting of the DDR and SUMOylation as a promising strategy for treating aggressive lymphoma.


Assuntos
Dano ao DNA , Linfoma de Células B , Humanos , Proteínas Adaptadoras de Transdução de Sinal , Linfócitos B , Reparo do DNA , Linfoma de Células B/genética
19.
Metabolites ; 13(8)2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37623902

RESUMO

Non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) have been linked to changes in amino acid (AA) levels. The objective of the current study was to examine the relationship between MRI parameters that reflect inflammation and fibrosis and plasma AA concentrations in NAFLD patients. Plasma AA levels of 97 NAFLD patients from the MAST4HEALTH study were quantified with liquid chromatography. Medical, anthropometric and lifestyle characteristics were collected and biochemical parameters, as well as inflammatory and oxidative stress biomarkers, were measured. In total, subjects with a higher MRI-proton density fat fraction (MRI-PDFF) exhibited higher plasma AA levels compared to subjects with lower PDFF. The concentrations of BCAAs (p-Value: 0.03), AAAs (p-Value: 0.039), L-valine (p-Value: 0.029), L-tyrosine (p-Value: 0.039) and L-isoleucine (p-Value: 0.032) were found to be significantly higher in the higher PDFF group compared to lower group. Plasma AA levels varied according to MRI-PDFF. Significant associations were also demonstrated between AAs and MRI-PDFF and MRI-cT1, showing the potential utility of circulating AAs as diagnostic markers of NAFLD.

20.
Blood Adv ; 7(15): 3874-3890, 2023 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-36867577

RESUMO

Multiple myeloma (MM) shows constitutive activation of canonical and noncanonical nuclear factor κB (NF-κB) signaling via genetic mutations or tumor microenvironment (TME) stimulations. A subset of MM cell lines showed dependency for cell growth and survival on the canonical NF-κB transcription factor RELA alone, suggesting a critical role for a RELA-mediated biological program in MM pathogenesis. Here, we determined the RELA-dependent transcriptional program in MM cell lines and found the expression of the cell surface molecules interleukin-27 receptor-α (IL-27Rα) and the adhesion molecule JAM2 to be responsive to RELA at the messenger RNA and protein levels. IL-27Rα and JAM2 were expressed on primary MM cells at higher levels than on healthy long-lived plasma cells (PCs) in the bone marrow. IL-27 activated STAT1, and to a lesser extent STAT3, in MM cell lines and in PCs generated from memory B cells in an IL-21-dependent in vitro PC differentiation assay. Concomitant activity of IL-21 and IL-27 enhanced differentiation into PCs and increased the cell-surface expression of the known STAT target gene CD38. In accordance, a subset of MM cell lines and primary MM cells cultured with IL-27 upregulated CD38 cell-surface expression, a finding with potential implications for enhancing the efficacy of CD38-directed monoclonal antibody therapies by increasing CD38 expression on tumor cells. The elevated expression of IL-27Rα and JAM2 on MM cells compared with that on healthy PCs may be exploited for the development of targeted therapeutic strategies that modulate the interaction of MM cells with the TME.


Assuntos
Interleucina-27 , Mieloma Múltiplo , Humanos , Interleucina-27/metabolismo , Mieloma Múltiplo/genética , NF-kappa B/metabolismo , Receptores de Citocinas/metabolismo , Microambiente Tumoral , Regulação para Cima
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