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1.
Cells ; 12(22)2023 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-37998385

RESUMO

The modulation of insulin/insulin-like growth factor signaling (IIS) is associated with altered nutritional and metabolic states. The Drosophila genome encodes eight insulin-like peptides, whose activity is regulated by a group of secreted factors, including Ecdysone-inducible gene L2 (ImpL2), which acts as a potent IIS inhibitor. We recently reported that cncC (cncC/Nrf2), the fly ortholog of Nrf2, is a positive transcriptional regulator of ImpL2, as part of a negative feedback loop aiming to suppress cncC/Nrf2 activity. This finding correlated with our observation that sustained cncC/Nrf2 overexpression/activation (cncCOE; a condition that signals organismal stress) deregulates IIS, causing hyperglycemia, the exhaustion of energy stores in flies' tissues, and accelerated aging. Here, we extend these studies in Drosophila by assaying the functional implication of ImpL2 in cncCOE-mediated metabolic deregulation. We found that ImpL2 knockdown (KD) in cncCOE flies partially reactivated IIS, attenuated hyperglycemia and restored tissue energetics. Moreover, ImpL2 KD largely suppressed cncCOE-mediated premature aging. In support, pharmacological treatment of cncCOE flies with Metformin, a first-line medication for type 2 diabetes, restored (dose-dependently) IIS functionality and extended cncCOE flies' longevity. These findings exemplify the effect of chronic stress in predisposition to diabetic phenotypes, indicating the potential prophylactic role of maintaining normal IIS functionality.


Assuntos
Diabetes Mellitus Tipo 2 , Proteínas de Drosophila , Hiperglicemia , Somatomedinas , Animais , Drosophila/metabolismo , Drosophila melanogaster/genética , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Insulina/metabolismo , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Somatomedinas/metabolismo
3.
Aging Cell ; 21(11): e13715, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36259256

RESUMO

The ubiquitin-proteasome pathway and its functional interplay with other proteostatic and/or mitostatic modules are crucial for cell viability, especially in post-mitotic cells like cardiomyocytes, which are constantly exposed to proteotoxic, metabolic, and mechanical stress. Consistently, treatment of multiple myeloma patients with therapeutic proteasome inhibitors may induce cardiac failure; yet the effects promoted by heart-targeted proteasome dysfunction are not completely understood. We report here that heart-targeted proteasome knockdown in the fly experimental model results in increased proteome instability and defective mitostasis, leading to disrupted cardiac activity, systemic toxicity, and reduced longevity. These phenotypes were partially rescued by either heart targeted- or by dietary restriction-mediated activation of autophagy. Supportively, activation of autophagy by Rapamycin or Metformin administration in flies treated with proteasome inhibitors reduced proteome instability, partially restored mitochondrial function, mitigated cardiotoxicity, and improved flies' longevity. These findings suggest that autophagic inducers represent a novel promising intervention against proteasome inhibitor-induced cardiovascular complications.


Assuntos
Complexo de Endopeptidases do Proteassoma , Inibidores de Proteassoma , Humanos , Complexo de Endopeptidases do Proteassoma/metabolismo , Inibidores de Proteassoma/farmacologia , Cardiotoxicidade , Proteoma/metabolismo , Autofagia/genética , Miócitos Cardíacos/metabolismo
4.
Front Endocrinol (Lausanne) ; 13: 840668, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35273575

RESUMO

Background: This is the first study, that aimed: a) to compare immune response, namely the kinetics of neutralizing antibodies (Nabs), after vaccination with BNT162b2 mRNA vaccine (Comirnaty, Pfizer/BioNTech) between patients with autoimmune thyroiditis and controls, and b) to investigate changes in thyroid function in healthy subjects with no history of thyroid dysfunction before and after vaccination with BNT162b2 mRNA vaccine (Comirnaty, Pfizer/BioNTech). Methods: The entire study consisted of two sub-studies. In the first sub-study, NAbs levels after BNT162b2 mRNA vaccination were compared between 56 patients with autoimmune thyroiditis and 56 age and gender-matched healthy controls from the day of the first dose until a period of up to three months after the second dose. In the second sub-study, thyroid hormones (T3, T4, TSH) and thyroid auto-antibodies levels (anti-TG, anti-TPO) of 72 healthy subjects with no history of thyroid disease were examined before (D1) and one month after completion of the second dose (D50). Results: Among patients with autoimmune thyroiditis, the median neutralizing inhibition on D22, immediately before second dose, was 62.5%. One month later (D50), values increased to 96.7%, while three months after the second dose NAbs titers remained almost the same (94.5%). In the healthy group, median NAbs levels at D22 were 53.6%. On D50 the median inhibition values increased to 95.1%, while after three months they were 89.2%. The statistical analysis did not show significant differences between two groups (p-values 0.164, 0.390, 0.105 for D22, D50 and three months). Regarding changes in thyroid function, the mean value for T4 before vaccination was 89.797 nmol/L and one month after the second dose was 89.11 nmol/L (p-value=0.649). On D1 the mean T3 value was 1.464 nmol/L, which dropped to 1.389 nmol/L on D50 (p-value = 0.004). For TSH, mean levels were 2.064 mIU/ml on D1 and fell to 1.840 mIU/ml one month after the second dose (p-value=0.037). Despite decrease, all thyroid hormone levels remained within the normal range. No changes were found for anti-TPO or anti-TG. Conclusions: This study provided evidence that patients with autoimmune thyroiditis present similar immunological response to COVID-19 BNT162b2 mRNA vaccine (Comirnaty, Pfizer/BioNTech) with healthy subjects, while vaccination may affect thyroid function.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Vacina BNT162/imunologia , COVID-19/imunologia , SARS-CoV-2/imunologia , Tireoidite Autoimune/imunologia , Adulto , Autoanticorpos/sangue , Autoanticorpos/imunologia , Vacina BNT162/administração & dosagem , Vacina BNT162/genética , COVID-19/prevenção & controle , COVID-19/virologia , Estudos de Casos e Controles , Feminino , Seguimentos , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , SARS-CoV-2/genética , Glândula Tireoide/metabolismo , Hormônios Tireóideos/sangue , Hormônios Tireóideos/metabolismo , Tireoidite Autoimune/metabolismo , Vacinação
5.
Sci Rep ; 12(1): 1649, 2022 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-35102193

RESUMO

As part of our screening program for the discovery of molecules of microbial origin with skin-whitening activity, 142 diverse fungal endophytes from a wide variety of Andalusia arid plants were screened, applying the OSMAC approach. The fungal strains CF-090361 and CF-090766, isolated from xerophytic plants, were selected as the most promising, while phylogenetic analysis revealed that both strains could represent a new species within the genus Comoclathris. The effect of different fermentation conditions on the production of tyrosinase inhibitory activity was examined, in order to identify the optimum cultivation conditions. LCMS based metabolomics was applied to determine significant differences between the strains and fermentation conditions, and to identify potential bioactive secondary metabolites. Bioassay-guided purification of the main active components led to the isolation of three new compounds (1-3), along with the known compounds graphostrin B (4) and brevianamide M (5). Compound 1 (Comoclathrin) demonstrated the strongest anti-tyrosinase activity (IC50 0.16 µΜ), which was 90-times higher than kojic acid (IC50 14.07 µΜ) used as positive control. Additionally, comoclathrin showed no significant cytotoxicity against a panel of cancer cell lines (HepG2, A2058, A549, MCF-7 and MIA PaCa-2) and normal BJ fibroblasts. These properties render comoclathrin an excellent development candidate as whitening agent.


Assuntos
Ascomicetos/metabolismo , Endófitos/metabolismo , Inibidores Enzimáticos/farmacologia , Monofenol Mono-Oxigenase/antagonistas & inibidores , Plantas/microbiologia , Preparações Clareadoras de Pele/farmacologia , Células A549 , Ascomicetos/genética , Sobrevivência Celular/efeitos dos fármacos , Clima Desértico , Endófitos/genética , Inibidores Enzimáticos/isolamento & purificação , Inibidores Enzimáticos/toxicidade , Células Hep G2 , Humanos , Células MCF-7 , Metaboloma , Metabolômica , Monofenol Mono-Oxigenase/metabolismo , Filogenia , Preparações Clareadoras de Pele/isolamento & purificação , Preparações Clareadoras de Pele/toxicidade
7.
Prostate Cancer Prostatic Dis ; 25(1): 117-118, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34628475

RESUMO

Data regarding the safety and efficacy of COVID-10 vaccines among cancer patients are lacking. Factors such as age, underlying disease and antineoplastic treatment confer negatively to the immune response due to vaccination. The degree of immunosuppression though may be lessen by targeted treatments like the androgen receptor-targeted agents (ARTA) that are commonly used in patients with metastatic prostate cancer. Herein, we report our data on 25 patients with prostate cancer under treatment with ARTA who were vaccinated for COVID-19. Our data suggest that these patients develop neutralizing antibodies against SARS-CoV-2 similarly to healthy volunteers. No safety issues were noted.


Assuntos
Antineoplásicos , COVID-19 , Neoplasias de Próstata Resistentes à Castração , Androstenos , Antineoplásicos/uso terapêutico , Benzamidas , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Humanos , Masculino , Nitrilas , Feniltioidantoína , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/patologia , SARS-CoV-2 , Resultado do Tratamento , Vacinação
8.
Clin Exp Med ; 22(2): 319-323, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34283338

RESUMO

Vaccination against SARS-CoV-2 is considered as the most important preventive strategy against COVID-19, but its efficacy in patients with hematological malignancies is largely unknown. We investigated the development of neutralizing antibodies (NAbs) against SARS-CoV-2 in patients with Waldenstrom Macroglobulinemia (WM), Chronic Lymphocytic Leukemia (CLL) and Non-Hodgkin Lymphoma (NHL). After the first dose of the vaccine, on D22, WM/CLL/NHL patients had lower NAb titers compared to controls: the median NAb inhibition titer was 17% (range 0-91%, IQR 8-27%) for WM/CLL/NHL patients versus 32% (range 2-98%, IQR 19-48%) for controls (P < 0.001). Only 8 (14%) patients versus 114 (54%) controls developed NAb titers ≥ 30% on D22 (p < 0.001). Our data indicate that the first dose of both BNT162b2 and AZD1222 leads to lower production of NAbs against SARS-CoV-2 in patients with WM/CLL/NHL compared to controls of similar age and gender and without malignant disease. Even though the response rates were not optimal, vaccination is still considered essential and if possible should be performed before treatment initiation. These patients with suboptimal responses should be considered to be prioritized for booster doses.


Assuntos
COVID-19 , Leucemia Linfocítica Crônica de Células B , Linfoma não Hodgkin , Macroglobulinemia de Waldenstrom , Anticorpos Neutralizantes , Anticorpos Antivirais , Vacina BNT162 , COVID-19/prevenção & controle , Vacinas contra COVID-19 , ChAdOx1 nCoV-19 , Humanos , SARS-CoV-2
9.
Br J Haematol ; 196(2): 356-359, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34528249

RESUMO

Patients with multiple myeloma (MM) have a suboptimal antibody response following vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and lower seroconversion rates following coronavirus disease 2019 (COVID-19) compared with healthy individuals. In this context, we evaluated the development of neutralising antibodies (NAbs) against SARS-CoV-2 in non-vaccinated patients with MM and COVID-19 compared with patients after vaccination with two doses of the BNT162b2 vaccine. Serum was collected either four weeks post confirmed diagnosis or four weeks post a second dose of BNT162b2. NAbs were measured with a Food and Drug Administration-approved enzyme-linked immunosorbent assay methodology. Thirty-five patients with COVID-19 and MM along with 35 matched patients were included. The two groups did not differ in age, sex, body mass index, prior lines of therapy, disease status, lymphocyte count, immunoglobulin levels and comorbidities. Patients with MM and COVID-19 showed a superior humoral response compared with vaccinated patients with MM. The median (interquartile range) NAb titre was 87·6% (71·6-94%) and 58·7% (21·4-91·8%) for COVID-19-positive and vaccinated patients, respectively (P = 0·01).Importantly, there was no difference in NAb production between COVID-19-positive and vaccinated patients who did not receive any treatment (median NAb 85·1% vs 91·7%, P = 0·14). In conclusion, our data indicate that vaccinated patients with MM on treatment without prior COVID-19 should be considered for booster vaccine doses.


Assuntos
Anticorpos Neutralizantes/biossíntese , Anticorpos Antivirais/biossíntese , Vacina BNT162/imunologia , COVID-19/imunologia , Mieloma Múltiplo/imunologia , SARS-CoV-2/imunologia , Adulto , Idoso , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , COVID-19/complicações , COVID-19/prevenção & controle , Teste Sorológico para COVID-19 , Epitopos/imunologia , Feminino , Humanos , Imunização Secundária , Hospedeiro Imunocomprometido , Imunogenicidade da Vacina , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/complicações , Estudos Prospectivos , Vacinação
10.
Life (Basel) ; 11(10)2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34685448

RESUMO

Elucidating long-term immunity following COVID-19 vaccination is essential for decision-making regarding booster shots. The aim of this study was to investigate the kinetics of neutralizing antibodies (Nabs) against SARS-CoV-2 up to six months after the second vaccination dose with the BNT162b2 mRNA vaccine. Nabs levels were measured on days 1 (before the first vaccine shot), 8, 22 (before the second shot), 36, 50, and 3 and 6 months after the second vaccination (NCT04743388). Three hundred and eight healthy individuals without malignant disease were included in this study. At six months, 2.59% of the participants had a Nabs value less than 30%, while 11.9% had Nabs values of less than 50%. Importantly, 58% of the subjects had Nabs values of more than 75%. Nabs were initially eliminated at a relatively slow rate, but after three months their elimination was 5.7 times higher. Older age was inversely associated with Nabs levels at all examined timepoints. Interestingly, a population modeling analysis estimated that half of the subjects will have Nabs values less than 73.8% and 64.6% at 9 and 12 months, respectively, post vaccination completion. In conclusion, we found a persistent but declining anti-SARS-CoV-2 humoral immunity at six months following full vaccination with BNT162b2 in healthy individuals, which was more pronounced among older persons. These data may inform the public health policies regarding the prioritization of booster vaccine shots.

11.
Blood Adv ; 5(21): 4398-4405, 2021 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-34529762

RESUMO

Immunocompromised patients with hematologic malignancies are more susceptible to COVID-19 and at higher risk of severe complications and worse outcomes compared with the general population. In this context, we evaluated the humoral response by determining the titers of neutralizing antibodies (NAbs) against SARS-CoV-2 in patients with Waldenström macroglobulinemia (WM) after vaccination with the BNT162b2 or AZD1222 vaccine. A US Food and Drug Administration-approved enzyme-linked immunosorbent assay-based methodology was implemented to evaluate NAbs on the day of the first vaccine shot, as well as on days 22 and 50 afterward. A total of 106 patients with WM (43% men; median age, 73 years) and 212 healthy controls (46% men; median age, 66 years) who were vaccinated during the same period at the same center were enrolled in the study (which is registered at www.clinicaltrials.gov as #NCT04743388). Our data indicate that vaccination with either 2 doses of the BNT162b2 or 1 dose of the AZD1222 vaccine leads to lower production of NAbs against SARS-CoV-2 in patients with WM compared with controls on days 22 and 50 (P < .001 for all comparisons). Disease-related immune dysregulation and therapy-related immunosuppression are involved in the low humoral response. Importantly, active treatment with either rituximab or Bruton's tyrosine kinase inhibitors was proven as an independent prognostic factor for suboptimal antibody response after vaccination. In conclusion, patients with WM have low humoral response after COVID-19 vaccination, which underlines the need for timely vaccination ideally during a treatment-free period and for continuous vigilance on infection control measures.


Assuntos
COVID-19 , Macroglobulinemia de Waldenstrom , Idoso , Anticorpos Neutralizantes , Anticorpos Antivirais , Vacina BNT162 , Vacinas contra COVID-19 , ChAdOx1 nCoV-19 , Feminino , Humanos , Masculino , Estudos Prospectivos , SARS-CoV-2 , Estados Unidos , Vacinação
12.
Cell Rep ; 36(6): 109504, 2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34352226

RESUMO

Early responses to vaccination are important for shaping both humoral and cellular protective immunity. Dissecting innate vaccine signatures may predict immunogenicity to help optimize the efficacy of mRNA and other vaccine strategies. Here, we characterize the cytokine and chemokine responses to the 1st and 2nd dose of the BNT162b2 mRNA (Pfizer/BioNtech) vaccine in antigen-naive and in previously coronavirus disease 2019 (COVID-19)-infected individuals (NCT04743388). Transient increases in interleukin-15 (IL-15) and interferon gamma (IFN-γ) levels early after boost correlate with Spike antibody levels, supporting their use as biomarkers of effective humoral immunity development in response to vaccination. We identify a systemic signature including increases in IL-15, IFN-γ, and IP-10/CXCL10 after the 1st vaccination, which were enriched by tumor necrosis factor alpha (TNF-α) and IL-6 after the 2nd vaccination. In previously COVID-19-infected individuals, a single vaccination results in both strong cytokine induction and antibody titers similar to the ones observed upon booster vaccination in antigen-naive individuals, a result with potential implication for future public health recommendations.


Assuntos
Vacinas contra COVID-19/imunologia , COVID-19/imunologia , Quimiocina CXCL10/imunologia , Interferon gama/imunologia , Interleucina-15/imunologia , SARS-CoV-2/imunologia , Adulto , Idoso , Anticorpos Antivirais/imunologia , Vacina BNT162 , COVID-19/metabolismo , Vacinas contra COVID-19/administração & dosagem , Feminino , Humanos , Imunidade/imunologia , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/imunologia
13.
Blood Cancer J ; 11(8): 138, 2021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-34341335

RESUMO

Recent data suggest a suboptimal antibody response to COVID-19 vaccination in patients with hematological malignancies. Neutralizing antibodies (NAbs) against SARS-CoV-2 were evaluated in 276 patients with plasma cell neoplasms after vaccination with either the BNT162b2 or the AZD1222 vaccine, on days 1 (before the first vaccine shot), 22, and 50. Patients with MM (n = 213), SMM (n = 38), and MGUS (n = 25) and 226 healthy controls were enrolled in the study (NCT04743388). Vaccination with either two doses of the BNT162b2 or one dose of the AZD1222 vaccine leads to lower production of NAbs in patients with MM compared with controls both on day 22 and on day 50 (p < 0.001 for all comparisons). Furthermore, MM patients showed an inferior NAb response compared with MGUS on day 22 (p = 0.009) and on day 50 (p = 0.003). Importantly, active treatment with either anti-CD38 monoclonal antibodies (Mabs) or belantamab mafodotin and lymphopenia at the time of vaccination were independent prognostic factors for suboptimal antibody response following vaccination. In conclusion, MM patients have low humoral response following SARS-CoV-2 vaccination, especially under treatment with anti-CD38 or belamaf. This underlines the need for timely vaccination, possibly during a treatment-free period, and for continuous vigilance on infection control measures in non-responders.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , Vacinas contra COVID-19 , COVID-19 , Mieloma Múltiplo , SARS-CoV-2 , Idoso , Idoso de 80 Anos ou mais , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , COVID-19/sangue , COVID-19/imunologia , COVID-19/prevenção & controle , Vacinas contra COVID-19/administração & dosagem , Vacinas contra COVID-19/imunologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/sangue , Mieloma Múltiplo/imunologia , Estudos Prospectivos , SARS-CoV-2/imunologia , SARS-CoV-2/metabolismo
14.
Front Neurosci ; 15: 660714, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34025345

RESUMO

Hereditary spastic paraplegia (HSP) is a group of inherited neurodegenerative conditions that share a characteristic feature of degeneration of the longest axons within the corticospinal tract, which leads to progressive spasticity and weakness of the lower limbs. Mutations of over 70 genes produce defects in various biological pathways: axonal transport, lipid metabolism, endoplasmic reticulum (ER) shaping, mitochondrial function, and endosomal trafficking. HSPs suffer from an adequate therapeutic plan. Currently the treatments foreseen for patients affected by this pathology are physiotherapy, to maintain the outgoing tone, and muscle relaxant therapies for spasticity. Very few clinical studies have been conducted, and it's urgent to implement preclinical animal studies devoted to pharmacological test and screening, to expand the rose of compounds potentially attractive for clinical trials. Small animal models, such as Drosophila melanogaster and zebrafish, have been generated, analyzed, and used as preclinical model for screening of compounds and their effects. In this work, we briefly described the role of HSP-linked proteins in the organization of ER endomembrane system and in the regulation of ER homeostasis and stress as a common pathological mechanism for these HSP forms. We then focused our attention on the pharmacodynamic and pharmacokinetic features of some recently identified molecules with antioxidant property, such as salubrinal, guanabenz, N-acetyl cysteine, methylene blue, rapamycin, and naringenin, and on their potential use in future clinical studies. Expanding the models and the pharmacological screening for HSP disease is necessary to give an opportunity to patients and clinicians to test new molecules.

16.
Bioorg Med Chem Lett ; 30(6): 126952, 2020 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-32005414

RESUMO

In the course of a primary screening of 614 microbial actinomycete extracts for the discovery of tyrosinase inhibitors, the EtOAc extract of the fermentation broth of the strain Streptomyces sp. CA-129531 isolated from a Martinique sample, exhibited in cell free and cell-based assays the most promising activity (IC50 value of 63 µg/mL). Scaled-up production in a bioreactor led to the isolation of one new trichostatic acid analogue, namely trichostatic acid B (1), along with six known trichostatin derivatives (2-7), four diketopiperazines (8-11), two butyrolactones (12-13) and one hydroxamic acid siderophore (14). Among them, trichostatin A (4) showed a Ki value of 6.1 µM and six times stronger anti-tyrosinase activity (IC50 2.18 µΜ) than kojic acid (IC50 14.07 µΜ) used as a positive control. Deoxytrichostatin A (6) displayed also strong inhibitory activity against tyrosinase (IC50 19.18 µΜ). Trichostatin A production in bioreactor started together with the exponential phase of growth (day 4) and the maximum concentration was reached at day 9 (2.67 ± 0.13 µg/mL). Despite the cytotoxicity of some individual components, the EtOAc extract showed no cytotoxic effect on HepG2, A2058, A549, MCF-7 and MIA PaCa-2 cell lines, (IC50 >2.84 mg/mL) and against BG fibroblasts at the concentrations where the whitening effect was exerted, reassuring its safety and great tyrosinase inhibitory potential.


Assuntos
Actinobacteria/química , Misturas Complexas/química , Inibidores Enzimáticos/química , Ácidos Hidroxâmicos/química , Monofenol Mono-Oxigenase/antagonistas & inibidores , Streptomyces/química , Reatores Biológicos , Sobrevivência Celular/efeitos dos fármacos , Misturas Complexas/metabolismo , Dicetopiperazinas/química , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/metabolismo , Fermentação , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Humanos , Ácidos Hidroxâmicos/metabolismo , Lactonas/química , Programas de Rastreamento , Pironas/química , Metabolismo Secundário/efeitos dos fármacos
17.
BMC Genomics ; 19(1): 37, 2018 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-29321003

RESUMO

BACKGROUND: Senescence is a fundamental biological process implicated in various pathologies, including cancer. Regarding carcinogenesis, senescence signifies, at least in its initial phases, an anti-tumor response that needs to be circumvented for cancer to progress. Micro-RNAs, a subclass of regulatory, non-coding RNAs, participate in senescence regulation. At the subcellular level micro-RNAs, similar to proteins, have been shown to traffic between organelles influencing cellular behavior. The differential function of micro-RNAs relative to their subcellular localization and their role in senescence biology raises concurrent in situ analysis of coding and non-coding gene products in senescent cells as a necessity. However, technical challenges have rendered in situ co-detection unfeasible until now. METHODS: In the present report we describe a methodology that bypasses these technical limitations achieving for the first time simultaneous detection of both a micro-RNA and a protein in the biological context of cellular senescence, utilizing the new commercially available SenTraGorTM compound. The method was applied in a prototypical human non-malignant epithelial model of oncogene-induced senescence that we generated for the purposes of the study. For the characterization of this novel system, we applied a wide range of cellular and molecular techniques, as well as high-throughput analysis of the transcriptome and micro-RNAs. RESULTS: This experimental setting has three advantages that are presented and discussed: i) it covers a "gap" in the molecular carcinogenesis field, as almost all corresponding in vitro models are fibroblast-based, even though the majority of neoplasms have epithelial origin, ii) it recapitulates the precancerous and cancerous phases of epithelial tumorigenesis within a short time frame under the light of natural selection and iii) it uses as an oncogenic signal, the replication licensing factor CDC6, implicated in both DNA replication and transcription when over-expressed, a characteristic that can be exploited to monitor RNA dynamics. CONCLUSIONS: Consequently, we demonstrate that our model is optimal for studying the molecular basis of epithelial carcinogenesis shedding light on the tumor-initiating events. The latter may reveal novel molecular targets with clinical benefit. Besides, since this method can be incorporated in a wide range of low, medium or high-throughput image-based approaches, we expect it to be broadly applicable.


Assuntos
Senescência Celular/genética , Neoplasias Epiteliais e Glandulares/genética , Oncogenes , Carcinogênese , Proteínas de Ciclo Celular/metabolismo , Células Cultivadas , Células Epiteliais/metabolismo , Perfilação da Expressão Gênica , Genoma , Humanos , MicroRNAs/metabolismo , Neoplasias Epiteliais e Glandulares/patologia , Neoplasias Epiteliais e Glandulares/ultraestrutura , Proteínas Nucleares/metabolismo , Proteínas/metabolismo
18.
Int J Mol Sci ; 18(10)2017 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-28937603

RESUMO

DNA damage is constantly produced by both endogenous and exogenous factors; DNA lesions then trigger the so-called DNA damaged response (DDR). This is a highly synchronized pathway that involves recognition, signaling and repair of the damage. Failure to eliminate DNA lesions is associated with genome instability, a driving force in tumorigenesis. Proteins carry out the vast majority of cellular functions and thus proteome quality control (PQC) is critical for the maintenance of cellular functionality. PQC is assured by the proteostasis network (PN), which under conditions of proteome instability address the triage decision of protein fold, hold, or degrade. Key components of the PN are the protein synthesis modules, the molecular chaperones and the two main degradation machineries, namely the autophagy-lysosome and the ubiquitin-proteasome pathways; also, part of the PN are a number of stress-responsive cellular sensors including (among others) heat shock factor 1 (Hsf1) and the nuclear factor erythroid 2-related factor 2 (Nrf2). Nevertheless, the lifestyle- and/or ageing-associated gradual accumulation of stressors results in increasingly damaged and unstable proteome due to accumulation of misfolded proteins and/or protein aggregates. This outcome may then increase genomic instability due to reduced fidelity in processes like DNA replication or repair leading to various age-related diseases including cancer. Herein, we review the role of proteostatic machineries in nuclear genome integrity and stability, as well as on DDR responses.


Assuntos
Instabilidade Genômica/fisiologia , Proteoma/metabolismo , Animais , Autofagia/genética , Autofagia/fisiologia , Dano ao DNA/genética , Dano ao DNA/fisiologia , Instabilidade Genômica/genética , Humanos , Estresse Oxidativo/genética , Estresse Oxidativo/fisiologia
19.
Oxid Med Cell Longev ; 2016: 4587691, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26977249

RESUMO

Mitochondria are highly dynamic organelles that provide essential metabolic functions and represent the major bioenergetic hub of eukaryotic cell. Therefore, maintenance of mitochondria activity is necessary for the proper cellular function and survival. To this end, several mechanisms that act at different levels and time points have been developed to ensure mitochondria quality control. An interconnected highly integrated system of mitochondrial and cytosolic chaperones and proteases along with the fission/fusion machinery represents the surveillance scaffold of mitostasis. Moreover, nonreversible mitochondrial damage targets the organelle to a specific autophagic removal, namely, mitophagy. Beyond the organelle dynamics, the constant interaction with the ubiquitin-proteasome-system (UPS) has become an emerging aspect of healthy mitochondria. Dysfunction of mitochondria and UPS increases with age and correlates with many age-related diseases including cancer and neurodegeneration. In this review, we discuss the functional cross talk of proteostasis and mitostasis in cellular homeodynamics and the impairment of mitochondrial quality control during ageing, cancer, and neurodegeneration.


Assuntos
Fenômenos Fisiológicos Celulares , Senescência Celular/fisiologia , Doença/etiologia , Homeostase/fisiologia , Mitocôndrias/fisiologia , Renovação Mitocondrial/fisiologia , Proteínas/metabolismo , Animais , Humanos , Mitofagia/fisiologia , Dobramento de Proteína
20.
PLoS Genet ; 11(4): e1005149, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25875445

RESUMO

Mutations in SPAST, encoding spastin, are the most common cause of autosomal dominant hereditary spastic paraplegia (HSP). HSP is characterized by weakness and spasticity of the lower limbs, owing to progressive retrograde degeneration of the long corticospinal axons. Spastin is a conserved microtubule (MT)-severing protein, involved in processes requiring rearrangement of the cytoskeleton in concert to membrane remodeling, such as neurite branching, axonal growth, midbody abscission, and endosome tubulation. Two isoforms of spastin are synthesized from alternative initiation codons (M1 and M87). We now show that spastin-M1 can sort from the endoplasmic reticulum (ER) to pre- and mature lipid droplets (LDs). A hydrophobic motif comprised of amino acids 57 through 86 of spastin was sufficient to direct a reporter protein to LDs, while mutation of arginine 65 to glycine abolished LD targeting. Increased levels of spastin-M1 expression reduced the number but increased the size of LDs. Expression of a mutant unable to bind and sever MTs caused clustering of LDs. Consistent with these findings, ubiquitous overexpression of Dspastin in Drosophila led to bigger and less numerous LDs in the fat bodies and increased triacylglycerol levels. In contrast, Dspastin overexpression increased LD number when expressed specifically in skeletal muscles or nerves. Downregulation of Dspastin and expression of a dominant-negative variant decreased LD number in Drosophila nerves, skeletal muscle and fat bodies, and reduced triacylglycerol levels in the larvae. Moreover, we found reduced amount of fat stores in intestinal cells of worms in which the spas-1 homologue was either depleted by RNA interference or deleted. Taken together, our data uncovers an evolutionarily conserved role of spastin as a positive regulator of LD metabolism and open up the possibility that dysfunction of LDs in axons may contribute to the pathogenesis of HSP.


Assuntos
Adenosina Trifosfatases/metabolismo , Proteínas de Drosophila/metabolismo , Gotículas Lipídicas/metabolismo , Metabolismo dos Lipídeos , Adenosina Trifosfatases/química , Adenosina Trifosfatases/genética , Motivos de Aminoácidos , Animais , Drosophila/genética , Drosophila/metabolismo , Proteínas de Drosophila/química , Proteínas de Drosophila/genética , Retículo Endoplasmático/metabolismo , Mucosa Intestinal/metabolismo , Músculo Esquelético/metabolismo , Neurônios/metabolismo , Transporte Proteico , Triglicerídeos/metabolismo
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