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1.
Am Heart J ; 228: 109-115, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32882569

RESUMO

BACKGROUND: Patients aged ≥80 years are often treated with new-generation drug-eluting stents (DES), but data from randomized studies are scarce owing to underrepresentation in most trials. We assessed 1-year clinical outcome of octogenarians treated with new-generation DES versus younger patients. METHODS: We pooled patient-level data of 9,204 participants in the TWENTE, DUTCH PEERS, BIO-RESORT, and BIONYX (TWENTE I-IV) randomized trials. The main clinical end point was target vessel failure (TVF), a composite of cardiac death, target vessel-related myocardial infarction (MI), or clinically indicated target vessel revascularization. RESULTS: The 671 octogenarian trial participants had significantly more comorbidities. TVF was higher in octogenarians than in 8,533 patients <80 years (7.3% vs 5.3%, hazard ratio [HR]: 1.36, 95% CI: 1.0-1.83, P = .04). The cardiac death rate was higher in octogenarians (3.9% vs 0.8%, P < .001). There was no significant between-group difference in target vessel MI (2.3% vs 2.3%, P = .88) and repeat target vessel revascularization (1.9% vs 2.8%, P = .16). In multivariate analyses, age ≥ 80 years showed no independent association with TVF (adjusted HR: 1.04, 95% CI: 0.76-1.42), whereas the risk of cardiac death remained higher in octogenarians (adjusted HR: 3.38, 95% CI: 2.07-5.52, P < .001). In 6,002 trial participants, in whom data on major bleeding were recorded, octogenarians (n = 459) showed a higher major bleeding risk (5.9% vs 1.9%; HR: 3.08, 95% CI: 2.01-4.74, P < .001). CONCLUSIONS: Octogenarian participants in 4 large-scale randomized DES trials had more comorbidities and a higher incidence of the main end point TVF. Cardiac mortality was higher in octogenarians, whereas there was no increase in MI or target vessel revascularization rates. Treatment of octogenarian patients with new-generation DES appears to be safe and effective.


Assuntos
Stents Farmacológicos/classificação , Everolimo/farmacologia , Infarto do Miocárdio , Complicações Pós-Operatórias , Sirolimo/análogos & derivados , Sirolimo/farmacologia , Idoso de 80 Anos ou mais , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/cirurgia , Feminino , Humanos , Imunossupressores/farmacologia , Masculino , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/mortalidade , Intervenção Coronária Percutânea , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/mortalidade , Reoperação/métodos , Reoperação/estatística & dados numéricos , Risco Ajustado/métodos , Fatores de Risco , Resultado do Tratamento
2.
Nat Commun ; 11(1): 4399, 2020 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-32879319

RESUMO

In cnidarians, axial patterning is not restricted to embryogenesis but continues throughout a prolonged life history filled with unpredictable environmental changes. How this developmental capacity copes with fluctuations of food availability and whether it recapitulates embryonic mechanisms remain poorly understood. Here we utilize the tentacles of the sea anemone Nematostella vectensis as an experimental paradigm for developmental patterning across distinct life history stages. By analyzing over 1000 growing polyps, we find that tentacle progression is stereotyped and occurs in a feeding-dependent manner. Using a combination of genetic, cellular and molecular approaches, we demonstrate that the crosstalk between Target of Rapamycin (TOR) and Fibroblast growth factor receptor b (Fgfrb) signaling in ring muscles defines tentacle primordia in fed polyps. Interestingly, Fgfrb-dependent polarized growth is observed in polyp but not embryonic tentacle primordia. These findings show an unexpected plasticity of tentacle development, and link post-embryonic body patterning with food availability.


Assuntos
Padronização Corporal , Anêmonas-do-Mar , Animais , Padronização Corporal/genética , Padronização Corporal/fisiologia , Desenvolvimento Embrionário/efeitos dos fármacos , Comportamento Alimentar , Regulação da Expressão Gênica no Desenvolvimento , Receptores de Fatores de Crescimento de Fibroblastos/genética , Receptores de Fatores de Crescimento de Fibroblastos/metabolismo , Anêmonas-do-Mar/embriologia , Anêmonas-do-Mar/genética , Anêmonas-do-Mar/crescimento & desenvolvimento , Transdução de Sinais , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/metabolismo
3.
Chem Biol Interact ; 330: 109243, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32861747

RESUMO

mTOR inhibitors are considered today to be one of the most promising anticancer drugs. Here to study the mechanism of the acquired resistance of MCF-7 breast cancer cells to mTOR inhibitors two different models of the cell resistance were used: rapamycin-resistant MCF-7/Rap subline developed under long-term rapamycin treatment, and metformin-resistant MCF-7/M subline obtained by long-term metformin treatment. We have found that both resistant sublines were characterized by common features: increased expression of mTOR-interacting Raptor protein, increased phosphorylation of Akt, and activation of growth-related transcriptional factor AP-1. Cell response to mTOR inhibitors was partially restored under treatment with PI3K inhibitor wortmannin supporting the direct connection between Akt activation and poor cell response to therapeutic drugs. Transfection of mir-181c, one of the positive regulators of Akt and mTOR, led to an increase in the cell resistance to both mTOR inhibitors, rapamycin and metformin, which correlated with Raptor overexpression and activation of Akt/AP-1 signaling. In general, the effect of Raptor overexpression in the resistant cells, as well as the ability of mir-181c to modulate the Raptor expression, can open novel perspectives in the treatment of rapalogues-resistant cancers, based on the drugs design targeting mir-181c/Raptor axis.


Assuntos
Neoplasias da Mama/patologia , Resistencia a Medicamentos Antineoplásicos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteína Regulatória Associada a mTOR/metabolismo , Sirolimo/farmacologia , Antibióticos Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Humanos , Células MCF-7 , MicroRNAs/genética , MicroRNAs/farmacologia , Transdução de Sinais , Regulação para Cima/efeitos dos fármacos
4.
PLoS Biol ; 18(8): e3000757, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32833957

RESUMO

In eukaryotes, conserved mechanisms ensure that cell growth is coordinated with nutrient availability. Overactive growth during nutrient limitation ("nutrient-growth dysregulation") can lead to rapid cell death. Here, we demonstrate that cells can adapt to nutrient-growth dysregulation by evolving major metabolic defects. Specifically, when yeast lysine-auxotrophic mutant lys- encountered lysine limitation, an evolutionarily novel stress, cells suffered nutrient-growth dysregulation. A subpopulation repeatedly evolved to lose the ability to synthesize organosulfurs (lys-orgS-). Organosulfurs, mainly reduced glutathione (GSH) and GSH conjugates, were released by lys- cells during lysine limitation when growth was dysregulated, but not during glucose limitation when growth was regulated. Limiting organosulfurs conferred a frequency-dependent fitness advantage to lys-orgS- by eliciting a proper slow growth program, including autophagy. Thus, nutrient-growth dysregulation is associated with rapid organosulfur release, which enables the selection of organosulfur auxotrophy to better tune cell growth to the metabolic environment. We speculate that evolutionarily novel stresses can trigger atypical release of certain metabolites, setting the stage for the evolution of new ecological interactions.


Assuntos
Adaptação Fisiológica/genética , Lisina/farmacologia , Redes e Vias Metabólicas/efeitos dos fármacos , Nutrientes/farmacologia , Saccharomyces cerevisiae/metabolismo , Autofagia/efeitos dos fármacos , Autofagia/genética , Evolução Biológica , Glucose/metabolismo , Glucose/farmacologia , Lisina/deficiência , Redes e Vias Metabólicas/genética , Nitrogênio/metabolismo , Nitrogênio/farmacologia , Nutrientes/metabolismo , Ribossomos/efeitos dos fármacos , Ribossomos/metabolismo , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Sirolimo/farmacologia , Estresse Fisiológico
5.
Gastroenterol Hepatol ; 43(8): 457-463, 2020 Oct.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-32646657

RESUMO

SARS-CoV-2 infection has produced a pandemic with serious consequences for our health care system. Although liver transplant patients represent only a minority of the population, the hepatologists who follow these patients have tried to coordinate efforts to produce a protocol the management of immunosuppression during SARS-CoV-2 infection. Although there are no solid studies to support general recommendations, experiences with other viral infections (hepatitis C, cytomegalovirus) suggest that management of immunosuppression without mycophenolate mofetil or m-Tor inhibitors (drugs that are also associated with leukopenia and lymphopenia) may be beneficial. It is also important to pay attention to possible drug interactions, especially in the case of tacrolimus, with some of the treatments with antiviral effect given in the context of COVID 19 (lopinavir/ritonavir, azithromycin). Finally, the immunosuppressive effect of immunomodulating drugs (tocilizumab and similar) administered to patients with severe lung disease should be taken into account. The mechanisms of action of the different immunosuppressive drugs are reviewed in this article, as well as their potential effect on SARS-CoV-2 infection, and suggests guidelines for the management of immunosuppression.


Assuntos
Betacoronavirus , Infecções por Coronavirus/epidemiologia , Imunossupressão/efeitos adversos , Imunossupressores/efeitos adversos , Transplante de Fígado , Pandemias , Pneumonia Viral/epidemiologia , Imunidade Adaptativa , Antivirais/farmacologia , Betacoronavirus/imunologia , Betacoronavirus/fisiologia , Inibidores de Calcineurina/efeitos adversos , Inibidores de Calcineurina/farmacologia , Inibidores de Calcineurina/uso terapêutico , Contraindicações de Medicamentos , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/imunologia , Suscetibilidade a Doenças , Interações Medicamentosas , Everolimo/efeitos adversos , Everolimo/farmacologia , Everolimo/uso terapêutico , Glucocorticoides/efeitos adversos , Glucocorticoides/farmacologia , Glucocorticoides/uso terapêutico , Humanos , Imunidade Inata , Hospedeiro Imunocomprometido , Imunossupressão/métodos , Imunossupressores/farmacologia , Imunossupressores/uso terapêutico , Ácido Micofenólico/efeitos adversos , Ácido Micofenólico/farmacologia , Ácido Micofenólico/uso terapêutico , Pneumonia Viral/imunologia , Complicações Pós-Operatórias/imunologia , Complicações Pós-Operatórias/prevenção & controle , Sirolimo/efeitos adversos , Sirolimo/farmacologia , Sirolimo/uso terapêutico , Serina-Treonina Quinases TOR/antagonistas & inibidores
6.
PLoS One ; 15(7): e0236403, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32716961

RESUMO

Autophagy, a self-degradative physiological process, is critical for homeostasis maintenance and energy source balancing in response to various stresses, including nutrient deprivation. It is a highly conserved catabolic process in eukaryotes and is indispensable for cell survival as it involves degradation of unessential or excessive components and their subsequent recycling as building blocks for the synthesis of necessary molecules. Although the dysregulation of autophagy has been reported to broadly contribute to various diseases, including cancers and neurodegenerative diseases, the molecular mechanisms underlying the epigenetic regulation of autophagy are poorly elucidated. Here, we report that the level of lysine demethylase 3B (KDM3B) increases in nutrient-deprived HCT116 cells, a colorectal carcinoma cell line, resulting in transcriptional activation of the autophagy-inducing genes. KDM3B was found to enhance the transcription by demethylating H3K9me2 on the promoter of these genes. Furthermore, we observed that the depletion of KDM3B inhibited the autophagic flux in HCT116 cells. Collectively, these data suggested the critical role of KDM3B in the regulation of autophagy-related genes via H3K9me2 demethylation and induction of autophagy in nutrient-starved HCT116 cells.


Assuntos
Autofagia/genética , Histona Desmetilases com o Domínio Jumonji/metabolismo , Ativação Transcricional/genética , Aminoácidos/deficiência , Autofagia/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Células HCT116 , Células HEK293 , Histonas/metabolismo , Humanos , Regiões Promotoras Genéticas , Complexo de Endopeptidases do Proteassoma/metabolismo , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Proteólise/efeitos dos fármacos , Sirolimo/farmacologia , Ativação Transcricional/efeitos dos fármacos , Proteína com Valosina/metabolismo
7.
PLoS Genet ; 16(6): e1008865, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32603360

RESUMO

Fpr1 (FK506-sensitive proline rotamase 1), a protein of the FKBP12 (FK506-binding protein 12 kDa) family in Saccharomyces cerevisiae, is a primary target for the immunosuppressive agents FK506 and rapamycin. Fpr1 inhibits calcineurin and TORC1 (target of rapamycin complex 1) when bound to FK506 and rapamycin, respectively. Although Fpr1 is recognised to play a crucial role in the efficacy of these drugs, its physiological functions remain unclear. In a hmo1Δ (high mobility group family 1-deleted) yeast strain, deletion of FPR1 induced severe growth defects, which could be alleviated by increasing the copy number of RPL25 (ribosome protein of the large subunit 25), suggesting that RPL25 expression was affected in hmo1Δfpr1Δ cells. In the current study, extensive chromatin immunoprecipitation (ChIP) and ChIP-sequencing analyses revealed that Fpr1 associates specifically with the upstream activating sequences of nearly all RPG (ribosomal protein gene) promoters, presumably in a manner dependent on Rap1 (repressor/activator site binding protein 1). Intriguingly, Fpr1 promotes the binding of Fhl1/Ifh1 (forkhead-like 1/interacts with forkhead 1), two key regulators of RPG transcription, to certain RPG promoters independently of and/or cooperatively with Hmo1. Furthermore, mutation analyses of Fpr1 indicated that for transcriptional function on RPG promoters, Fpr1 requires its N-terminal domain and the binding surface for rapamycin, but not peptidyl-prolyl isomerase activity. Notably, Fpr1 orthologues from other species also inhibit TORC1 when bound to rapamycin, but do not regulate transcription in yeast, which suggests that these two functions of Fpr1 are independent of each other.


Assuntos
Proteínas de Grupo de Alta Mobilidade/metabolismo , Peptidilprolil Isomerase/metabolismo , Proteínas Ribossômicas/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Fatores de Transcrição/metabolismo , Calcineurina/metabolismo , Sequenciamento de Cromatina por Imunoprecipitação , Fatores de Transcrição Forkhead/metabolismo , Regulação Fúngica da Expressão Gênica , Genes Fúngicos , Proteínas de Grupo de Alta Mobilidade/genética , Peptidilprolil Isomerase/genética , Regiões Promotoras Genéticas/genética , Ligação Proteica/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/antagonistas & inibidores , Proteínas de Saccharomyces cerevisiae/genética , Sirolimo/farmacologia , Tacrolimo/farmacologia , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/genética , Transcrição Genética
8.
Aging (Albany NY) ; 12(11): 10004-10021, 2020 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-32534452

RESUMO

COVID-19 is not deadly early in life, but mortality increases exponentially with age, which is the strongest predictor of mortality. Mortality is higher in men than in women, because men age faster, and it is especially high in patients with age-related diseases, such as diabetes and hypertension, because these diseases are manifestations of aging and a measure of biological age. At its deepest level, aging (a program-like continuation of developmental growth) is driven by inappropriately high cellular functioning. The hyperfunction theory of quasi-programmed aging explains why COVID-19 vulnerability (lethality) is an age-dependent syndrome, linking it to other age-related diseases. It also explains inflammaging and immunosenescence, hyperinflammation, hyperthrombosis, and cytokine storms, all of which are associated with COVID-19 vulnerability. Anti-aging interventions, such as rapamycin, may slow aging and age-related diseases, potentially decreasing COVID-19 vulnerability.


Assuntos
Envelhecimento , Infecções por Coronavirus/mortalidade , Pneumonia Viral/mortalidade , Animais , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Senescência Celular , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/metabolismo , Citocinas/metabolismo , Suscetibilidade a Doenças , Humanos , Pandemias , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/metabolismo , Sirolimo/farmacologia , Sirolimo/uso terapêutico
9.
Arch Biochem Biophys ; 689: 108461, 2020 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-32531316

RESUMO

The phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) signaling pathway plays an important role in the development of papillary thyroid cancer. While rapamycin has been shown to exhibit anti-tumor effects, it may also activate AKT, resulting in increased cell survival and drug resistance, thereby limiting its anti-tumor effects. Resveratrol can also inhibit tumor growth by regulating the PI3K/AKT/mTOR signaling pathway. The present study investigated the anti-tumor effects of the combined use of rapamycin and resveratrol in papillary thyroid cancer. We first treated two human papillary thyroid cancer cell lines (KTC-1 and TPC-1) with single or combined administration, and examined the effects on proliferation, the cell cycle, apoptosis, and invasion/migration of papillary thyroid cancer cells. A mouse xenograft model was induced with KTC-1 and TPC-1 cells followed by treatment with single or combined administration. Body weight and tumor size were monitored to assess the toxicity of each compound. The phosphorylation of AKT and the mTORC1 target p70S6 kinase (p70S6K) in tumors was also examined. Both rapamycin and resveratrol inhibited proliferation, altered the cell cycle, and induced apoptosis of papillary thyroid cancer cells. Invasion and migration were also reduced, as was the tumor growth rate in the xenograft model. Co-administration significantly enhanced the anti-tumor effects than use of any one drug, and significantly reduced the phosphorylation of AKT and p70S6K compared to treatment with rapamycin alone. Overall, compared to single use of rapamycin or resveratrol, co-administration had a synergistic effect in inhibiting proliferation and invasion/migration of papillary thyroid cancer cells and inducing apoptosis. Resveratrol is sensitizing the anti-tumor effects of rapamycin and the PI3K/AKT/mTOR signaling is involved. Although further animal and clinical studies are needed to clarify the mechanism and assess drug safety, the present study suggests that the combination of rapamycin and resveratrol may be a promising strategy for the treatment of papillary thyroid cancer.


Assuntos
Antineoplásicos/uso terapêutico , Resveratrol/uso terapêutico , Sirolimo/uso terapêutico , Câncer Papilífero da Tireoide/tratamento farmacológico , Neoplasias da Glândula Tireoide/tratamento farmacológico , Animais , Antineoplásicos/farmacologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sinergismo Farmacológico , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Resveratrol/farmacologia , Transdução de Sinais/efeitos dos fármacos , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/metabolismo , Câncer Papilífero da Tireoide/metabolismo , Neoplasias da Glândula Tireoide/metabolismo
10.
Int J Nanomedicine ; 15: 3771-3790, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32547027

RESUMO

Introduction: Rapamycin has been considered as a potential treatment for osteoarthritis (OA). Drug carriers fabricated from liposomes can prolong the effects of drugs and reduce side effects of drugs. Low-intensity pulsed ultrasound (LIPUS) has been found to possess anti-OA effects. Materials and Methods: The anti-osteoarthritic effects of liposome-encapsulated rapamycin (L-rapa) combined with LIPUS were examined by culture of normal and OA chondrocytes in alginate beads and further validated in OA prone Dunkin-Hartley guinea pigs. Results: L-rapa with LIPUS largely up-regulated aggrecan and type II collagen mRNA in human OA chondrocytes (HOACs). L-rapa with LIPUS caused significant enhancement in proteoglycan and type II collagen production in HOACs. Large decreases in both MMP-13 and IL-6 proteins were found in the HOACs exposed to L-rapa with LIPUS. Intra-articular injection of 40 µL L-rapa at both 5 µM and 50 µM twice a week combined with LIPUS thrice a week for 8 weeks significantly increased GAGs and type II collagen in the cartilage of knee. Results on OARSI score showed that intra-articular injection of 5 µM L-rapa with LIPUS displayed the greatest anti-OA effects. Immunohistochemistry revealed that L-rapa with or without LIPUS predominantly reduced MMP-13 in vivo. The values of complete blood count and serum biochemical examinations remained in the normal ranges after the injections with or without LIPUS. These data indicated that intra-articular injection of L-rapa collaborated with LIPUS is not only effective against OA but a safe OA therapy. Conclusion: Taken together, L-rapa combined with LIPUS possessed the most consistently and effectively anabolic and anti-catabolic effects in HOACs and the spontaneous OA guinea pigs. This study evidently revealed that liposome-encapsulation collaborated with LIPUS is able to reduce the effective dose and administration frequency of rapamycin and further stably reinforce its therapeutic actions against OA.


Assuntos
Osteoartrite/terapia , Sirolimo/uso terapêutico , Ondas Ultrassônicas , Animais , Peso Corporal/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Células Cultivadas , Condrócitos/efeitos dos fármacos , Condrócitos/patologia , Condrócitos/efeitos da radiação , Colágeno Tipo II/metabolismo , Liberação Controlada de Fármacos , Cobaias , Humanos , Injeções Intra-Articulares , Interleucina-6/metabolismo , Lipossomos/ultraestrutura , Masculino , Metaloproteinase 13 da Matriz/metabolismo , Pessoa de Meia-Idade , Osteoartrite/sangue , Osteoartrite/patologia , Proteoglicanas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Sirolimo/administração & dosagem , Sirolimo/farmacologia
11.
PLoS One ; 15(6): e0233887, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32492043

RESUMO

Increased cytoplasmic lipid droplets (LDs) and elevated AKT/mTOR signaling are characteristics of clear cell renal cell carcinoma (ccRCC). Lysophosphatidic acid (LPA), a potent lipid mitogen generated via autotaxin (elevated in ccRCC), can modulate tumor progression but its role in altering chemotherapeutic sensitivity to mTOR inhibitors is unclear and thus is the focus of the studies presented herein. Using malignant (A-498, 769-P and 786-O) and normal immortalized kidney (HK-2) cell lines, we investigated their cellular responsiveness to Temsirolimus (TEMS, mTOR inhibitor) in the absence or presence of LPA by monitoring alterations in AKT/mTOR pathway mediators (via western blotting), LDs (using LipidTOX and real-time PCR to assess transcript changes in modulators of LD biogenesis/turnover), mitochondrial networks (via immunofluorescence staining for TOM20 and TOM70), as well as cellular viability. We identified that TEMS reduced cellular viability in all renal cell lines, with increased sensitivity in the presence of an autophagy inhibitor. TEMS also altered activation of AKT/mTOR pathway mediators, abundance of LDs, and fragmentation of mitochondrial networks. We observed that these effects were antagonized by LPA. In HK-2 cells, LPA markedly increased LD size and abundance, coinciding with phospho-MAPK and phospho-S6 activation, increased diacylglycerol O-acetyltransferase 2 (DGAT2) mRNA (which produces triacylglycerides), and survival. Inhibiting MAPK partially antagonized LPA-induced LD changes. Collectively, we have identified that LPA can reverse the effects of TEMS by increasing LDs in a MAPK-dependent manner; these results suggest that LPA may contribute to the pathogenesis and chemotherapeutic resistance of ccRCC.


Assuntos
Antineoplásicos/farmacologia , Carcinoma de Células Renais/tratamento farmacológico , Neoplasias Renais/tratamento farmacológico , Lisofosfolipídeos/metabolismo , Sirolimo/análogos & derivados , Antineoplásicos/uso terapêutico , Autofagia/efeitos dos fármacos , Carcinoma de Células Renais/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos , Humanos , Hidroxicloroquina/farmacologia , Hidroxicloroquina/uso terapêutico , Neoplasias Renais/patologia , Gotículas Lipídicas/efeitos dos fármacos , Gotículas Lipídicas/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Diester Fosfórico Hidrolases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sirolimo/farmacologia , Sirolimo/uso terapêutico , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/metabolismo
12.
Nucleic Acids Res ; 48(10): 5407-5425, 2020 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-32356874

RESUMO

Adjusting DNA structure via epigenetic modifications, and altering polyadenylation (pA) sites at which precursor mRNA is cleaved and polyadenylated, allows cells to quickly respond to environmental stress. Since polyadenylation occurs co-transcriptionally, and specific patterns of nucleosome positioning and chromatin modifications correlate with pA site usage, epigenetic factors potentially affect alternative polyadenylation (APA). We report that the histone H3K4 methyltransferase Set1, and the histone H3K36 methyltransferase Set2, control choice of pA site in Saccharomyces cerevisiae, a powerful model for studying evolutionarily conserved eukaryotic processes. Deletion of SET1 or SET2 causes an increase in serine-2 phosphorylation within the C-terminal domain of RNA polymerase II (RNAP II) and in the recruitment of the cleavage/polyadenylation complex, both of which could cause the observed switch in pA site usage. Chemical inhibition of TOR signaling, which causes nutritional stress, results in Set1- and Set2-dependent APA. In addition, Set1 and Set2 decrease efficiency of using single pA sites, and control nucleosome occupancy around pA sites. Overall, our study suggests that the methyltransferases Set1 and Set2 regulate APA induced by nutritional stress, affect the RNAP II C-terminal domain phosphorylation at Ser2, and control recruitment of the 3' end processing machinery to the vicinity of pA sites.


Assuntos
Histona-Lisina N-Metiltransferase/fisiologia , Metiltransferases/fisiologia , Poliadenilação , Proteínas de Saccharomyces cerevisiae/fisiologia , Saccharomyces cerevisiae/genética , Cromatina/química , Cromatina/efeitos dos fármacos , Deleção de Genes , Regulação Fúngica da Expressão Gênica , Histona-Lisina N-Metiltransferase/genética , Histonas , Metiltransferases/genética , Nucleossomos/metabolismo , RNA Polimerase II/metabolismo , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Sirolimo/farmacologia , Fatores de Poliadenilação e Clivagem de mRNA/metabolismo
13.
Bratisl Lek Listy ; 121(4): 308-315, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32356448

RESUMO

AIM: The aim of this study was to analyze the effects of rapamycin treatment on apoptosis via mTOR pathway in metastatic and non-metastatic human breast cancer cell lines by immunohistochemical and TUNEL analysis. METHOD: MCF-7 and MDA-MB 231 cell lines were incubated under standard conditions forming Rapamycin and control groups. In immunohistochemical evaluation; mTOR pathway was evaluated with anti-IGF1, anti-PI3K, anti-pAKT1/2/3, anti-mTORC1, anti-mTORC2 and anti-ERK1 antibodies. The effect of apoptosis was also confirmed by TUNEL method. RESULTS: In this study, activation of PI3K/AKT/mTOR and related molecular pathways in the MDA-MB 231 and MCF-7 breast cancer cell line was evaluated and it was observed that these pathways could play a key role in cancer development. Increased apoptotic cells were observed in mTORC1 inhibition by Rapamycin administration. CONCLUSION: Targeting the mTOR pathway in breast cancer treatment may be a treatment option. In addition, the demonstration and confirmation of increased apoptosis in Rapamycin treated groups suggested that Rapamycin, an inhibitor of mTOR, is promising in the treatment of breast cancer (Tab. 2, Fig. 3, Ref. 66).


Assuntos
Apoptose , Neoplasias da Mama/patologia , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/metabolismo , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Células MCF-7 , Metástase Neoplásica , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo
14.
Life Sci ; 253: 117747, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32376270

RESUMO

AIMS: Multiple sclerosis (MS) whose pathogenesis is still unclear is a chronic progressive disease in the central nervous system. Gut microbiota can directly or indirectly affect the immune system through the brain gut axis to engage in the occurrence and development of the disease. MATERIALS AND METHODS: C57BL/6 mice which were immunized by MOG35-55 to prepare experimental autoimmune encephalomyelitis (EAE) animal models were treated with rapamycin and MCC950 (CP-456773) in combination or separately. After sequencing the 16S rRNA V4 region of gut microbiota, the species, abundance and composition of gut microbiota were analyzed by Alpha diversity, Bata diversity and LEfSe analysis. The pathological changes and the expression of CD4 and CD8 of brain, large intestine and spleen were detected. KEY FINDINGS: The results showed that rapamycin and MCC950 could alleviate the progression of the disease by inducing autophagy and inhibiting the immune response. The Alpha diversity of EAE model group was no significant difference compering to control group while the number of OTUs was decreased. After the treatment by rapamycin and MCC950, the abundance and composition of gut microbiota was relatively recovered, which was close to that of normal mice. SIGNIFICANCE: Inhibiting immune cell-mediated inflammation and restoring the composition of gut microbiota may help to alleviate the clinical symptoms of multiple sclerosis. Furthermore, to research the regulatory effect between immune response and gut microbiota may be a new strategy for the prevention and treatment of multiple sclerosis.


Assuntos
Encefalomielite Autoimune Experimental/tratamento farmacológico , Furanos/farmacologia , Microbioma Gastrointestinal/imunologia , Esclerose Múltipla/tratamento farmacológico , Sirolimo/farmacologia , Sulfonamidas/farmacologia , Animais , Encéfalo/imunologia , Encéfalo/fisiopatologia , Modelos Animais de Doenças , Progressão da Doença , Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/microbiologia , Feminino , Furanos/administração & dosagem , Inflamação/imunologia , Inflamação/patologia , Intestino Grosso/imunologia , Intestino Grosso/patologia , Camundongos , Camundongos Endogâmicos C57BL , Esclerose Múltipla/imunologia , Esclerose Múltipla/microbiologia , RNA Ribossômico 16S , Sirolimo/administração & dosagem , Baço/imunologia , Baço/patologia , Sulfonamidas/administração & dosagem
15.
Cancer Sci ; 111(5): 1607-1618, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32232883

RESUMO

Sunitinib, a multitargeted receptor tyrosine kinase inhibitor including vascular endothelial growth factor, has been widely used as a first-line treatment against metastatic renal cell carcinoma (mRCC). However, mRCC often acquires resistance to sunitinib, rendering it difficult to treat with this agent. Recently, Rapalink-1, a drug that links rapamycin and the mTOR kinase inhibitor MLN0128, has been developed with excellent therapeutic effects against breast cancer cells carrying mTOR resistance mutations. The aim of the present study was to evaluate the in vitro and in vivo therapeutic efficacy of Rapalink-1 against renal cell carcinoma (RCC) compared to temsirolimus, which is commonly used as a small molecule inhibitor of mTOR and is a derivative of rapamycin. In comparison with temsirolimus, Rapalink-1 showed significantly greater effects against proliferation, migration, invasion and cFolony formation in sunitinib-naïve RCC cells. Inhibition was achieved through suppression of the phosphorylation of substrates in the mTOR signal pathway, such as p70S6K, eukaryotic translation initiation factor 4E-binding protein 1 (4EBP1) and AKT. In addition, Rapalink-1 had greater tumor suppressive effects than temsirolimus against the sunitinib-resistant 786-o cell line (SU-R 786-o), which we had previously established, as well as 3 additional SU-R cell lines established here. RNA sequencing showed that Rapalink-1 suppressed not only the mTOR signaling pathway but also a part of the MAPK signaling pathway, the ErbB signaling pathway and ABC transporters that were associated with resistance to several drugs. Our study suggests the possibility of a new treatment option for patients with RCC that is either sunitinib-sensitive or sunitinib-resistant.


Assuntos
Carcinoma de Células Renais/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Neoplasias Renais/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Sirolimo/análogos & derivados , Sunitinibe/farmacologia , Serina-Treonina Quinases TOR/antagonistas & inibidores , Animais , Apoptose/efeitos dos fármacos , Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/patologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Neoplasias Renais/metabolismo , Neoplasias Renais/patologia , Camundongos , Camundongos Nus , Inibidores de Proteínas Quinases/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Sirolimo/farmacologia , Sirolimo/uso terapêutico , Sunitinibe/uso terapêutico , Serina-Treonina Quinases TOR/metabolismo
16.
Life Sci ; 252: 117662, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32298739

RESUMO

AIMS: Bronchopulmonary dysplasia (BPD) is a severe respiratory complication in preterm infants. This study reveals the molecular mechanism of autophagic agonists regulating the Nrf2-ARE pathway via p62 to improve alveolar development in BPD rats. MAIN METHODS: Newborn Sprague-Dawley rats were randomly exposed to a hyperoxic environment (FiO2 = 0.85) for 14 days and rapamycin (RAPA) was intraperitoneally injected on alternate days into hyperoxia-exposed mice. Alveolar development was assessed using HE and RAC values. Markers associated with the p62-Keap1-Nrf2-ARE pathway were detected by western blot, immunohistochemistry, and RT-PCR. Co-localization of proteins was determined using double immunofluorescence staining. KEY FINDINGS: At the levels of lung tissue and primary type II alveolar epithelial cells, the enhanced binding between phosphorylated p62 and Keap1 disrupted the nuclear transport of Nrf2. The activated Nrf2 was insufficient to reverse alveolar simplification. The autophagy agonist was able to inhibit p62 phosphorylation, promote Keap1 degradation, increase Nrf2 nuclear transport, augment downstream antioxidant enzyme expression, and enhance antioxidant capacity, thereby improving the simplification of alveolar structure in BPD rats. SIGNIFICANCE: The use of autophagy agonists to enhance the Nrf2-ARE pathway activity and promote alveolar development could be a novel target in antioxidant therapy for BPD.


Assuntos
Autofagia/efeitos dos fármacos , Displasia Broncopulmonar/fisiopatologia , Alvéolos Pulmonares/metabolismo , Sirolimo/farmacologia , Animais , Animais Recém-Nascidos , Elementos de Resposta Antioxidante , Antioxidantes/metabolismo , Modelos Animais de Doenças , Humanos , Hiperóxia/complicações , Recém-Nascido , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Camundongos , Fator 2 Relacionado a NF-E2/metabolismo , Ratos , Ratos Sprague-Dawley
17.
Einstein (Sao Paulo) ; 18: eAO4560, 2020.
Artigo em Inglês, Português | MEDLINE | ID: mdl-32321078

RESUMO

OBJECTIVE: To investigate if ICI 182,780 (fulvestrant), a selective estrogen receptor alpha/beta (ERα/ERß) antagonist, and G-1, a selective G-protein-coupled receptor (GPER) agonist, can potentially induce autophagy in breast cancer cell lines MCF-7 and SKBr3, and how G-1 affects cell viability. METHODS: Cell viability in MCF-7 and SKBr3 cells was assessed by the MTT assay. To investigate the autophagy flux, MCF-7 cells were transfected with GFP-LC3, a marker of autophagosomes, and analyzed by real-time fluorescence microscopy. MCF-7 and SKBr3 cells were incubated with acridine orange for staining of acidic vesicular organelles and analyzed by flow cytometry as an indicator of autophagy. RESULTS: Regarding cell viability in MCF-7 cells, ICI 182,780 and rapamycin, after 48 hours, led to decreased cell proliferation whereas G-1 did not change viability over the same period. The data showed that neither ICI 182,780 nor G-1 led to increased GFP-LC3 puncta in MCF-7 cells over the 4-hour observation period. The cytometry assay showed that ICI 182,780 led to a higher number of acidic vesicular organelles in MCF-7 cells. G-1, in turn, did not have this effect in any of the cell lines. In contrast, ICI 182,780 and G-1 did not decrease cell viability of SKBr3 cells or induce formation of acidic vesicular organelles, which corresponds to the final step of the autophagy process in this cell line. CONCLUSION: The effect of ICI 182,780 on increasing acidic vesicular organelles in estrogen receptor-positive breast cancer cells appears to be associated with its inhibitory effect on estrogen receptors, and GPER does notseem to be involved. Understanding these mechanisms may guide further investigations of these receptors' involvement in cellular processes of breast cancer resistance.


Assuntos
Autofagia/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Antagonistas do Receptor de Estrogênio/farmacologia , Fulvestranto/farmacologia , Receptores Acoplados a Proteínas-G/agonistas , Análise de Variância , Western Blotting , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Receptor alfa de Estrogênio/antagonistas & inibidores , Receptor beta de Estrogênio/antagonistas & inibidores , Feminino , Citometria de Fluxo/métodos , Humanos , Células MCF-7 , Receptores Acoplados a Proteínas-G/análise , Reprodutibilidade dos Testes , Sirolimo/farmacologia , Fatores de Tempo , Transfecção/métodos
18.
Proc Natl Acad Sci U S A ; 117(18): 9973-9980, 2020 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-32303657

RESUMO

When transitioning from the environment, pathogenic microorganisms must adapt rapidly to survive in hostile host conditions. This is especially true for environmental fungi that cause opportunistic infections in immunocompromised patients since these microbes are not well adapted human pathogens. Cryptococcus species are yeastlike fungi that cause lethal infections, especially in HIV-infected patients. Using Cryptococcus deneoformans in a murine model of infection, we examined contributors to drug resistance and demonstrated that transposon mutagenesis drives the development of 5-fluoroorotic acid (5FOA) resistance. Inactivation of target genes URA3 or URA5 primarily reflected the insertion of two transposable elements (TEs): the T1 DNA transposon and the TCN12 retrotransposon. Consistent with in vivo results, increased rates of mutagenesis and resistance to 5FOA and the antifungal drugs rapamycin/FK506 (rap/FK506) and 5-fluorocytosine (5FC) were found when Cryptococcus was incubated at 37° compared to 30° in vitro, a condition that mimics the temperature shift that occurs during the environment-to-host transition. Inactivation of the RNA interference (RNAi) pathway, which suppresses TE movement in many organisms, was not sufficient to elevate TE movement at 30° to the level observed at 37°. We propose that temperature-dependent TE mobilization in Cryptococcus is an important mechanism that enhances microbial adaptation and promotes pathogenesis and drug resistance in the human host.


Assuntos
Antifúngicos/farmacologia , Cryptococcus neoformans/efeitos dos fármacos , Micoses/genética , Retroelementos/genética , Animais , Antifúngicos/efeitos adversos , Cryptococcus neoformans/patogenicidade , Farmacorresistência Fúngica/genética , Interações Hospedeiro-Patógeno/genética , Humanos , Camundongos , Mutagênese/genética , Micoses/microbiologia , Ácido Orótico/efeitos adversos , Ácido Orótico/análogos & derivados , Ácido Orótico/farmacologia , Sirolimo/farmacologia , Tacrolimo/farmacologia , Virulência/genética
19.
Nat Commun ; 11(1): 1771, 2020 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-32286306

RESUMO

The hexosamine biosynthetic pathway (HBP) plays critical roles in nutrient sensing, stress response, and cell growth. However, its contribution to cardiac hypertrophic growth and heart failure remains incompletely understood. Here, we show that the HBP is induced in cardiomyocytes during hypertrophic growth. Overexpression of Gfat1 (glutamine:fructose-6-phosphate amidotransferase 1), the rate-limiting enzyme of HBP, promotes cardiomyocyte growth. On the other hand, Gfat1 inhibition significantly blunts phenylephrine-induced hypertrophic growth in cultured cardiomyocytes. Moreover, cardiac-specific overexpression of Gfat1 exacerbates pressure overload-induced cardiac hypertrophy, fibrosis, and cardiac dysfunction. Conversely, deletion of Gfat1 in cardiomyocytes attenuates pathological cardiac remodeling in response to pressure overload. Mechanistically, persistent upregulation of the HBP triggers decompensated hypertrophy through activation of mTOR while Gfat1 deficiency shows cardioprotection and a concomitant decrease in mTOR activity. Taken together, our results reveal that chronic upregulation of the HBP under hemodynamic stress induces pathological cardiac hypertrophy and heart failure through persistent activation of mTOR.


Assuntos
Hexosaminas/metabolismo , Miócitos Cardíacos/metabolismo , Acetilglucosamina , Animais , Proliferação de Células/genética , Proliferação de Células/fisiologia , Ecocardiografia , Glutamina-Frutose-6-Fosfato Transaminase (Isomerizante)/genética , Glutamina-Frutose-6-Fosfato Transaminase (Isomerizante)/metabolismo , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miócitos Cardíacos/efeitos dos fármacos , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Sirolimo/farmacologia , Proteína 1 de Ligação a X-Box/genética , Proteína 1 de Ligação a X-Box/metabolismo
20.
Phytother Res ; 34(9): 2246-2257, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32246575

RESUMO

SophoraflavanoneG (SG), an important prenylated flavonoid isolated from Sophoraalopecuroides.L, is effective for many illnesses. The present study was designed to investigate whether the compound could reverse depressive-like symptoms and investigate its possible mechanisms. Chronic Unpredictable Mild Stress (CUMS) mice were treated with fluoxetine and SG. The immobility time in forced swimming test (FST) and tail suspension test (TST) were recorded. The levels of pro-inflammatory cytokines and neurotransmitters in the hippocampus were evaluated. Furthermore, the protein expressions of PI3K, AKT, mTOR, p70S6K, BDNF, and Trkb in hippocampus were detected. Rapamycin, the selective mTOR inhibitor, was used to estimate the potential mechanism. As a result, after 7 days of SG treatment, the immobility time in FST and TST was declined obviously. The levels of IL-6, IL-1ß, and TNF-α in the hippocampus were significantly reduced, and the quantity of 5-HT and NE was raised considerably in SG-treated group compared with the CUMS-exposed group. Additionally, SG could up-regulate the expressions of PI3K, AKT, mTOR, 70S6K, BDNF, and Trkb. The blockade of mammalian target of rapamycin signaling blunted the antidepressant effect and reversed the up-regulation of BDNF expression caused by SG. These findings suggested that SG treatment alleviated depressive-like symptoms via mTOR-mediated BDNF/Trkb signaling.


Assuntos
Antidepressivos/farmacologia , Flavanonas/farmacologia , Estresse Psicológico/patologia , Serina-Treonina Quinases TOR/fisiologia , Animais , Comportamento Animal/efeitos dos fármacos , Doença Crônica , Depressão/tratamento farmacológico , Depressão/metabolismo , Modelos Animais de Doenças , Preferências Alimentares/efeitos dos fármacos , Elevação dos Membros Posteriores , Hipocampo/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Transdução de Sinais/efeitos dos fármacos , Sirolimo/farmacologia , Estresse Psicológico/metabolismo , Sacarose/administração & dosagem , Serina-Treonina Quinases TOR/metabolismo
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