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1.
BMJ Case Rep ; 17(10)2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39353669

RESUMO

Rosai-Dorfman disease (RDD) is a rare myeloproliferative disorder involving histiocytes, with an incidence of 1:200 000 and approximately 100 new cases diagnosed annually in the USA. The condition presents a diverse range of clinical manifestations, and early recognition and treatment generally result in a favourable prognosis. However, diagnosing RDD poses challenges due to its rarity. The clinical management of RDD lacks a consensus, further complicating its diagnostic and therapeutic approach. We present a case of a man in his late 50s with RDD who experienced worsening cytopenias, including severe neutropenia and respiratory distress, despite an initial positive response to steroids, rituximab and lenalidomide. Genetic testing revealed mutations in POLE, KRAS (G13C), NDE1 and EZH2, suggesting potential new therapeutic targets. Sirolimus was initiated and led to complete radiological remission of the disease. This case adds strength to the growing evidence supporting the efficacy of sirolimus in refractory RDD cases.


Assuntos
Histiocitose Sinusal , Sirolimo , Humanos , Histiocitose Sinusal/tratamento farmacológico , Histiocitose Sinusal/diagnóstico , Masculino , Pessoa de Meia-Idade , Sirolimo/uso terapêutico , Rituximab/uso terapêutico , Resultado do Tratamento , Imunossupressores/uso terapêutico
2.
Trials ; 25(1): 642, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39354527

RESUMO

BACKGROUND: Aging leads to a decline in muscle mass and strength, contributing to frailty and decreased quality of life. Sirolimus (rapamycin) , an mTOR inhibitor, has shown potential in preclinical studies to extend lifespan and improve health span. This study evaluates the safety and efficacy of once-weekly sirolimus (rapamycin) administration on muscle strength and endurance in older adults engaged in a 13-week exercise program. METHODS: This randomized, double-blind, placebo-controlled trial will enroll 40 participants aged 65-85. Participants will be randomly assigned to receive either sirolimus (rapamycin) 6 mg/week or placebo for 13 weeks, in conjunction with an at-home exercise program. The primary outcome measure is the change in muscle strength and endurance, assessed by the 30-Second Chair-Stand Test. Secondary outcome measures include adverse events, changes in muscle strength and endurance as measured by the 6-min walk test, handgrip strength, and participant-reported outcomes using the SF-36 survey. Assessments will be conducted at baseline, mid-intervention (week 6), and post-intervention (week 13). Blood samples will be collected for hematology and biochemistry analyses, including full blood count, urea and electrolytes, liver function tests, HbA1c, lipids, serum IGF-1, and hs-CRP. DNA methylation will be analyzed using TruDiagnostic™ to explore changes in biological age. DISCUSSION: This study aims to provide insights into the potential benefits of intermittent sirolimus (rapamycin) administration on muscle performance in older adults. By alternating periods of mTOR inhibition through rapamycin and activation via exercise, this study will explore a novel approach to enhancing muscle strength and endurance in the aging population. The results could have significant implications for developing interventions to improve physical function and overall health outcomes in older adults. Safety and tolerability will also be closely monitored to ensure the feasibility of this regimen for wider application. TRIAL REGISTRATION: Australia New Zealand Clinical Trials Registry, ACTRN12624000790549. Registered on 26 June 2024 https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?ACTRN=12624000790549 .


Assuntos
Força Muscular , Sirolimo , Humanos , Método Duplo-Cego , Sirolimo/administração & dosagem , Sirolimo/efeitos adversos , Idoso , Força Muscular/efeitos dos fármacos , Idoso de 80 Anos ou mais , Masculino , Feminino , Resistência Física/efeitos dos fármacos , Ensaios Clínicos Controlados Aleatórios como Assunto , Esquema de Medicação , Resultado do Tratamento , Inibidores de MTOR/administração & dosagem , Inibidores de MTOR/efeitos adversos , Músculo Esquelético/efeitos dos fármacos , Terapia por Exercício/métodos , Qualidade de Vida , Fatores de Tempo
3.
Acta Cir Bras ; 39: e397324, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39258620

RESUMO

PURPOSE: To compare the endothelial coverage of different stents in porcine carotid arteries. Research problem: How effective are polyurethane stents (PU) and PU + rapamycin (PU + RAPA) compared to bare-metal stents on endothelial coverage by neointima in pigs after 28 days? METHODS: The methodology had two phases for an interventional, experimental, prospective study, with three Moura pigs, 12 weeks old and weighing between 19 and 22.5 kg. In phase I, eight stents were implanted in carotid arteries; three stents coated with PU, three coated with PU + RAPA, and two without coating. After 28 days, phase II was carried out, consisting of euthanasia, removal of the stents, to evaluate the exposed area of the stent struts, and the percentage of endothelialization through optical microscopy and scanning electron microscopy. RESULTS: The eight stents implanted with ultrasound sizing and post-dilation with a larger diameter balloon were analyzed by Doppler ultrasound, intravascular ultrasound, and angiography after 28 days. CONCLUSIONS: This study showed complete endothelial coverage by the endoluminal neointima of the stent struts, good integration and coverage with the arterial wall, with no exposed struts showing the presence of intimal hyperplasia (whitish tissue).


Assuntos
Stents Farmacológicos , Sirolimo , Animais , Sirolimo/administração & dosagem , Sirolimo/farmacologia , Suínos , Artérias Carótidas/cirurgia , Artérias Carótidas/efeitos dos fármacos , Neointima/patologia , Microscopia Eletrônica de Varredura , Poliuretanos , Estudos Prospectivos , Endotélio Vascular/efeitos dos fármacos , Reprodutibilidade dos Testes , Polímeros , Modelos Animais , Fatores de Tempo , Materiais Revestidos Biocompatíveis
4.
Sci Rep ; 14(1): 20832, 2024 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-39242621

RESUMO

Pluripotent stem cells can differentiate into distinct cell types but the intracellular pathways controlling cell fate choice are not well understood. The social amoeba Dictyostelium discoideum is a simplified system to study choice preference as proliferating amoebae enter a developmental cycle upon starvation and differentiate into two major cell types, stalk and spores, organised in a multicellular fruiting body. Factors such as acidic vesicle pH predispose amoebae to one fate. Here we show that the mechanistic target of rapamycin complex 1 (mTORC1) pathway has a role in cell fate bias in Dictyostelium. Inhibiting the mTORC1 pathway activity by disruption of Rheb (activator Ras homolog enriched in brain), or treatment with the mTORC1 inhibitor rapamycin prior to development, biases cells to a spore cell fate. Conversely activation of the pathway favours stalk cell differentiation. The Set1 histone methyltransferase, responsible for histone H3 lysine4 methylation, in Dictyostelium cells regulates transcription at the onset of development. Disruption of Set1 leads to high mTORC1 pathway activity and stalk cell predisposition. The ability of the mTORC1 pathway to regulate cell fate bias of cells undergoing differentiation offers a potential target to increase the efficiency of stem cell differentiation into a particular cell type.


Assuntos
Diferenciação Celular , Dictyostelium , Alvo Mecanístico do Complexo 1 de Rapamicina , Transdução de Sinais , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Dictyostelium/metabolismo , Dictyostelium/genética , Histona-Lisina N-Metiltransferase/metabolismo , Histona-Lisina N-Metiltransferase/genética , Sirolimo/farmacologia , Proteínas de Protozoários/metabolismo , Proteínas de Protozoários/genética , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Proteínas Monoméricas de Ligação ao GTP/genética
6.
Diab Vasc Dis Res ; 21(5): 14791641241283939, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39311502

RESUMO

BACKGROUND: Diabetes mellitus is associated with higher risk of target lesion failure (TLF) after percutaneous coronary intervention. We studied the 5-year outcome in patients with diabetes mellitus treated with biodegradable polymer stents. METHODS: The SORT OUT VII was a randomised trial comparing the ultrathin sirolimus-eluting Orsiro stent (O-SES) and the biolimus-eluting Nobori stent (N-BES) in an all-comer setting. Patients (n = 2525) were randomised to receive O-SES (n = 1261, diabetes: n = 236) or N-BES (n = 1264, diabetes: n = 235). Endpoints were TLF (a composite of cardiac death, target-lesion myocardial infarction (MI), target lesion revascularization (TLR)), definite stent thrombosis and a patient related outcome (all-cause mortality, MI and revascularization) within 5 years. RESULTS: Patients with diabetes mellitus had higher TLF (20.6% vs 11.0%, (Rate ratio (RR) 1.85 95% confidence interval (CI): (1.42-2.40) and patient related outcome (42.0% vs 31.0%, RR 1.43 95% CI: (1.19-1.71)) compared to patients without diabetes. Among patients with diabetes mellitus, TLF after 5 years did not differ between O-SES and N-BES (21.2% vs 20.0%), RR 1.05 95% CI: (0.70-1.58), p = 0.81). Cardiac death, MI, TLR, and definite stent thrombosis did not differ between the groups. CONCLUSION: In patients with diabetes mellitus, 5-year outcomes were similar among patients treated with biodegradable polymer O-SES or N-BES. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT01879358.


Assuntos
Implantes Absorvíveis , Fármacos Cardiovasculares , Doença da Artéria Coronariana , Diabetes Mellitus , Stents Farmacológicos , Intervenção Coronária Percutânea , Desenho de Prótese , Sirolimo , Humanos , Sirolimo/administração & dosagem , Sirolimo/análogos & derivados , Sirolimo/efeitos adversos , Intervenção Coronária Percutânea/instrumentação , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/mortalidade , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Resultado do Tratamento , Fatores de Tempo , Doença da Artéria Coronariana/terapia , Doença da Artéria Coronariana/mortalidade , Doença da Artéria Coronariana/diagnóstico por imagem , Fármacos Cardiovasculares/efeitos adversos , Fármacos Cardiovasculares/administração & dosagem , Fatores de Risco , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/mortalidade , Polímeros , Trombose Coronária/etiologia , Trombose Coronária/prevenção & controle , Infarto do Miocárdio/mortalidade
7.
J Vis Exp ; (211)2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39311602

RESUMO

Tyrosine phosphatases are an important family of enzymes that regulate critical physiological functions. They are often dysregulated in human diseases, making them key targets of biological studies. Tools that enable the regulation of phosphatase activity are instrumental in the dissection of their function. Traditional approaches, such as overexpression of constitutively active or dominant negative mutants, or downregulation using siRNA, lack temporal control. Phosphatase inhibitors often have poor specificity, and they only allow researchers to determine what processes are affected by the inhibition of the phosphatase. We developed a chemogenetic approach, the Rapamycin-regulated (RapR) system, which allows for allosteric regulation of a phosphatase catalytic domain that enables tight temporal control of phosphatase activation. The RapR system consists of an iFKBP domain inserted into an allosteric site in the phosphatase. The intrinsic structural dynamics of the RapR domain disrupt the catalytic domain, leading to the inactivation of the enzyme. The addition of rapamycin mediates the formation of a complex between iFKBP and a co-expressed FRB protein, which stabilizes iFKBP and restores activity to the phosphatase's catalytic domain. This system provides high specificity and tight temporal control of phosphatase activation in living cells. The unique capabilities of this system enable the identification of transient events and interrogation of individual signaling pathways downstream of a phosphatase. This protocol describes guidelines for the development of a RapR-phosphatase, its biochemical characterization, and the analysis of its effects on downstream signaling and regulation of cell morphodynamics. It also provides a detailed description of a protein engineering strategy, in vitro assays analyzing phosphatase activity, and live cell imaging experiments identifying changes in cell morphology.


Assuntos
Proteínas Tirosina Fosfatases , Sirolimo , Sirolimo/farmacologia , Humanos , Proteínas Tirosina Fosfatases/metabolismo , Proteínas Tirosina Fosfatases/genética , Proteínas Tirosina Fosfatases/química , Proteínas Tirosina Fosfatases/antagonistas & inibidores , Regulação Alostérica/efeitos dos fármacos , Domínio Catalítico
8.
ACS Appl Mater Interfaces ; 16(37): 48993-49002, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39225760

RESUMO

Pulmonary fibrosis is a lethal interstitial lung disease, for which current treatments are inadequate in halting its progression. A significant factor contributing to the development of fibrosis is insufficient autophagy, which leads to increased fibroblast proliferation and collagen deposition. However, treatments aimed at upregulating autophagy often cause further lung pathology due to the disruption of epithelial cell balance. In response, we have developed a novel macrophage delivery system loaded with an epithelial-to-mesenchymal transition inhibitor, hyperoside (HYP), and an autophagy inducer, rapamycin (RAP). This system targets the fibrotic areas of the lung through chemotaxis, releases liposomes via macrophage extracellular traps, and effectively inhibits fibroblast proliferation while restoring the alveolar structure through the combined effects of RAP and HYP, ultimately reducing lung pathology without causing systemic toxicity. Our findings not only highlight a promising method to enhance autophagy-based treatments for pulmonary fibrosis but also demonstrate the potential of macrophages as effective nanocarriers for drug delivery.


Assuntos
Autofagia , Transição Epitelial-Mesenquimal , Macrófagos , Fibrose Pulmonar , Quercetina , Sirolimo , Autofagia/efeitos dos fármacos , Sirolimo/farmacologia , Sirolimo/química , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Fibrose Pulmonar/tratamento farmacológico , Fibrose Pulmonar/patologia , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/metabolismo , Animais , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Quercetina/química , Quercetina/farmacologia , Quercetina/análogos & derivados , Humanos , Regulação para Cima/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Sistemas de Liberação de Medicamentos , Células RAW 264.7
9.
Lancet ; 404(10457): 1040-1050, 2024 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-39236727

RESUMO

BACKGROUND: The long-term impact of drug-coated balloon (DCB) angioplasty for the treatment of patients with de novo coronary artery lesions remains uncertain. We aimed to assess the non-inferiority of DCB angioplasty with rescue stenting to intended drug-eluting stent (DES) deployment for patients with de novo, non-complex coronary artery lesions. METHODS: REC-CAGEFREE I was an open-label, randomised, non-inferiority trial conducted at 43 sites in China. After successful lesion pre-dilatation, patients aged 18 years or older with de novo, non-complex coronary artery disease (irrespective of target vessel diameter) and an indication for percutaneous coronary intervention were randomly assigned (1:1), via a web-based centralised system with block randomisation (block size of two, four, or six) and stratified by site, to paclitaxel-coated balloon angioplasty with the option of rescue stenting due to an unsatisfactory result (DCB group) or intended deployment of second-generation thin-strut sirolimus-eluting stents (DES group). The primary outcome was the device-oriented composite endpoint (DoCE; including cardiovascular death, target vessel myocardial infarction, and clinically and physiologically indicated target lesion revascularisation) assessed at 24 months in the intention-to-treat (ITT) population (ie, all participants randomly assigned to treatment). Non-inferiority was established if the upper limit of the one-sided 95% CI for the absolute risk difference was smaller than 2·68%. Safety was assessed in the ITT population. This study is registered with ClinicalTrials.gov, NCT04561739. It is closed to accrual and extended follow-up is ongoing. FINDINGS: Between Feb 5, 2021, and May 1, 2022, 2272 patients were randomly assigned to the DCB group (1133 [50%]) or the DES group (1139 [50%]). Median age at the time of randomisation was 62 years (IQR 54-69), 1574 (69·3%) of 2272 were male, 698 (30·7%) were female, and all patients were of Chinese ethnicity. 106 (9·4%) of 1133 patients in the DCB group received rescue DES after unsatisfactory DCB angioplasty. As of data cutoff (May 1, 2024), median follow-up was 734 days (IQR 731-739). At 24 months, the DoCE occurred in 72 (6·4%) of 1133 patients in the DCB group and 38 (3·4%) of 1139 in the DES group, with a risk difference of 3·04% in the cumulative event rate (upper boundary of the one-sided 95% CI 4·52; pnon-inferiority=0·65; two-sided 95% CI 1·27-4·81; p=0·0008); the criterion for non-inferiority was not met. During intervention, no acute vessel closures occurred in the DCB group and one (0·1%) of 1139 patients in the DES group had acute vessel closure. Periprocedural myocardial infarction occurred in ten (0·9%) of 1133 patients in the DCB group and nine (0·8%) in the DES group. INTERPRETATION: In patients with de novo, non-complex coronary artery disease, irrespective of vessel diameter, a strategy of DCB angioplasty with rescue stenting did not achieve non-inferiority compared with the intended DES implantation in terms of the DoCE at 2 years, which indicates that DES should remain the preferred treatment for this patient population. FUNDING: Xijing Hospital and Shenqi Medical. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.


Assuntos
Angioplastia Coronária com Balão , Doença da Artéria Coronariana , Stents Farmacológicos , Paclitaxel , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Angioplastia Coronária com Balão/métodos , Paclitaxel/administração & dosagem , Paclitaxel/uso terapêutico , Doença da Artéria Coronariana/terapia , Idoso , Sirolimo/uso terapêutico , Sirolimo/administração & dosagem , Resultado do Tratamento , Materiais Revestidos Biocompatíveis , China/epidemiologia , Intervenção Coronária Percutânea/métodos
10.
Int J Nanomedicine ; 19: 9821-9841, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39345910

RESUMO

Purpose: Renal cell carcinoma (RCC) is the most common and lethal type of urogenital cancer, with one-third of new cases presenting as metastatic RCC (mRCC), which, being the seventh most common cancer in men and the ninth in women, poses a significant challenge. For patients with poor prognosis, temsirolimus (TEM) has been approved for first-line therapy, possessing pharmacodynamic activities that block cancer cell growth and inhibit proliferation-associated proteins. However, TEM suffers from poor water solubility, low bioavailability, and systemic side effects. This study aims to develop a novel drug formulation for the treatment of RCC. Methods: In this study, amphiphilic block copolymer (poly(ethylene glycol) monomethyl ether-poly(beta-amino ester)) (mPEG-PBAE) was utilized as a drug delivery vehicle and TEM-loaded micelles were prepared by thin-film hydration method by loading TEM inside the nanoparticles. Then, the molecular weight of mPEG-PBAE was controlled to make it realize hydrophobic-hydrophilic transition in the corresponding pH range thereby constructing pH-responsive TEM-loaded micelles. Characterization of pH-responsive TEM-loaded nanomicelles particle size, potential and micromorphology while its determination of drug-loading properties, in vitro release properties. Finally, pharmacodynamics and hepatorenal toxicity were further evaluated. Results: TEM loading in mPEG-PBAE increased the solubility of TEM in water from 2.6 µg/mL to more than 5 mg/mL. The pH-responsive TEM-loaded nanomicelles were in the form of spheres or spheroidal shapes with an average particle size of 43.83 nm and a Zeta potential of 1.79 mV. The entrapment efficiency (EE) of pH-responsive TEM nanomicelles with 12.5% drug loading reached 95.27%. Under the environment of pH 6.7, the TEM was released rapidly within 12 h, and the release rate could reach 73.12% with significant pH-dependent characteristics. In vitro experiments showed that mPEG-PBAE preparation of TEM-loaded micelles had non-hemolytic properties and had significant inhibitory effects on cancer cells. In vivo experiments demonstrated that pH-responsive TEM-loaded micelles had excellent antitumor effects with significantly reduced liver and kidney toxicity. Conclusion: In conclusion, we successfully prepared pH-responsive TEM-loaded micelles. The results showed that pH-responsive TEM-loaded micelles can achieve passive tumor targeting of TEM, and take advantage of the acidic conditions in tumor tissues to achieve rapid drug release.


Assuntos
Antineoplásicos , Carcinoma de Células Renais , Neoplasias Renais , Micelas , Polietilenoglicóis , Sirolimo , Sirolimo/administração & dosagem , Sirolimo/química , Sirolimo/farmacocinética , Sirolimo/farmacologia , Sirolimo/análogos & derivados , Humanos , Polietilenoglicóis/química , Concentração de Íons de Hidrogênio , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/farmacocinética , Antineoplásicos/administração & dosagem , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/patologia , Carcinoma de Células Renais/tratamento farmacológico , Linhagem Celular Tumoral , Tamanho da Partícula , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Camundongos , Sobrevivência Celular/efeitos dos fármacos , Liberação Controlada de Fármacos , Feminino , Masculino
11.
Cells ; 13(18)2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-39329778

RESUMO

Lung cancer remains a formidable health challenge due to its high mortality and morbidity rates. Non-small cell lung cancer (NSCLC) constitutes approximately 85% of all lung cancer cases, with small cell lung cancer (SCLC) accounting for the remainder. Both NSCLC and SCLC cells express receptor tyrosine kinases, which may be overexpressed or mutated in lung cancer, leading to increased activation. The c-Met receptor tyrosine kinase, crucial for cell transformation and tumor growth, invasion, and metastasis, became the focus of our study. We used an E1B55KD-deleted, replication-selective oncolytic adenovirus (Ad.What), driven by the c-Met promoter, targeting lung cancer cells with c-Met overexpression, thus sparing normal cells. Previous studies have shown the enhanced antitumor efficacy of oncolytic adenoviruses when combined with chemotherapeutic agents. We explored combining rapamycin, a selective mTOR inhibitor with promising clinical trial outcomes for various cancers, with Ad.What. This combination increased infectivity by augmenting the expression of coxsackievirus and adenovirus receptors and αV integrin on cancer cells and induced autophagy. Our findings suggest that combining a c-Met promoter-driven oncolytic adenovirus with rapamycin could be an effective lung cancer treatment strategy, offering a targeted approach to exploit lung cancer cells' vulnerabilities, potentially marking a significant advancement in managing this deadly disease.


Assuntos
Adenoviridae , Neoplasias Pulmonares , Terapia Viral Oncolítica , Vírus Oncolíticos , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-met , Sirolimo , Humanos , Proteínas Proto-Oncogênicas c-met/metabolismo , Proteínas Proto-Oncogênicas c-met/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/terapia , Neoplasias Pulmonares/patologia , Regiões Promotoras Genéticas/genética , Adenoviridae/genética , Linhagem Celular Tumoral , Terapia Viral Oncolítica/métodos , Vírus Oncolíticos/genética , Sirolimo/farmacologia , Sirolimo/uso terapêutico , Animais , Camundongos , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/terapia , Carcinoma Pulmonar de Células não Pequenas/patologia
12.
Int J Mol Sci ; 25(18)2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39337528

RESUMO

mTOR plays a crucial role in cell growth by controlling ribosome biogenesis, metabolism, autophagy, mRNA translation, and cytoskeleton organization. It is a serine/threonine kinase that is part of two distinct extensively described protein complexes, mTORC1 and mTORC2. We have identified a rapamycin-resistant mTOR complex, called mTORC3, which is different from the canonical mTORC1 and mTORC2 complexes in that it does not contain the Raptor, Rictor, or mLST8 mTORC1/2 components. mTORC3 phosphorylates mTORC1 and mTORC2 targets and contains the ETS transcription factor ETV7, which binds to mTOR and is essential for mTORC3 assembly in the cytoplasm. Tumor cells that assemble mTORC3 have a proliferative advantage and become resistant to rapamycin, indicating that inhibiting mTORC3 may have a therapeutic impact on cancer. Here, we investigate which domains or amino acid residues of ETV7 and mTOR are involved in their mutual binding. We found that the mTOR FRB and LBE sequences in the kinase domain interact with the pointed (PNT) and ETS domains of ETV7, respectively. We also found that forced expression of the mTOR FRB domain in the mTORC3-expressing, rapamycin-resistant cell line Karpas-299 out-competes mTOR for ETV7 binding and renders these cells rapamycin-sensitive in vivo. Our data provide useful information for the development of molecules that prevent the assembly of mTORC3, which may have therapeutic value in the treatment of mTORC3-positive cancer.


Assuntos
Ligação Proteica , Proteínas Proto-Oncogênicas c-ets , Serina-Treonina Quinases TOR , Humanos , Serina-Treonina Quinases TOR/metabolismo , Proteínas Proto-Oncogênicas c-ets/metabolismo , Proteínas Proto-Oncogênicas c-ets/genética , Linhagem Celular Tumoral , Sirolimo/farmacologia , Animais , Domínios Proteicos , Fosforilação , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Células HEK293
13.
Int J Mol Sci ; 25(17)2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39273610

RESUMO

Gamma-interferon-inducible lysosomal thiol reductase (GILT) plays pivotal roles in both adaptive and innate immunities. GILT exhibits constitutive expression within antigen-presenting cells, whereas in other cell types, its expression is induced by interferon gamma (IFN-γ). Gaining insights into the precise molecular mechanism governing the induction of GILT protein by IFN-γ is of paramount importance for adaptive and innate immunities. In this study, we found that the 5' segment of GILT mRNA inhibited GILT protein expression regardless of the presence of IFN-γ. Conversely, the 3' segment of GILT mRNA suppressed GILT protein expression in the absence of IFN-γ, but it loses this inhibitory effect in its presence. Although the mTOR inhibitor rapamycin suppressed the induction of GILT protein expression by IFN-γ, the expression from luciferase sequence containing the 3' segment of GILT mRNA was resistant to rapamycin in the presence of IFN-γ, but not in its absence. Collectively, this study elucidates the mechanism behind GILT induction by IFN-γ: in the absence of IFN-γ, GILT mRNA is constitutively transcribed, but the translation process is hindered by both the 5' and 3' segments. Upon exposure to IFN-γ, a translation inhibitor bound to the 3' segment is liberated, and a translation activator interacts with the 3' segment to trigger the initiation of GILT translation.


Assuntos
Interferon gama , Fatores de Transcrição , Interferon gama/farmacologia , Interferon gama/metabolismo , Humanos , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Sirolimo/farmacologia , Oxirredutases atuantes sobre Doadores de Grupo Enxofre
14.
Biol Sex Differ ; 15(1): 72, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39278930

RESUMO

BACKGROUND: Sex differences exist in the prevalence and progression of major glomerular diseases. Podocytes are the essential cell-type in the kidney which maintain the physiological blood-urine barrier, and pathological changes in podocyte homeostasis are critical accelerators of impairment of kidney function. However, sex-specific molecular signatures of podocytes under physiological and stress conditions remain unknown. This work aimed at identifying sexual dimorphic molecular signatures of podocytes under physiological condition and pharmacologically challenged homeostasis with mechanistic target of rapamycin (mTOR) inhibition. mTOR is a crucial regulator involved in a variety of physiological and pathological stress responses in the kidney and inhibition of this pathway may therefore serve as a general stress challenger to get fundamental insights into sex differences in podocytes. METHODS: The genomic ROSAmT/mG-NPHS2 Cre mouse model was used which allows obtaining highly pure podocyte fractions for cell-specific molecular analyses, and vehicle or pharmacologic treatment with the mTOR inhibitor rapamycin was performed for 3 weeks. Subsequently, deep RNA sequencing and proteomics were performed of the isolated podocytes to identify intrinsic sex differences. Studies were supplemented with metabolomics from kidney cortex tissues. RESULTS: Although kidney function and morphology remained normal in all experimental groups, RNA sequencing, proteomics and metabolomics revealed strong intrinsic sex differences in the expression levels of mitochondrial, translation and structural transcripts, protein abundances and regulation of metabolic pathways. Interestingly, rapamycin abolished prominent sex-specific clustering of podocyte gene expression and induced major changes only in male transcriptome. Several sex-biased transcription factors could be identified as possible upstream regulators of these sexually dimorphic responses. Concordant to transcriptomics, metabolomic changes were more prominent in males. Remarkably, high number of previously reported kidney disease genes showed intrinsic sexual dimorphism and/or different response patterns towards mTOR inhibition. CONCLUSIONS: Our results highlight remarkable intrinsic sex-differences and sex-specific response patterns towards pharmacological challenged podocyte homeostasis which might fundamentally contribute to sex differences in kidney disease susceptibilities and progression. This work provides rationale and an in-depth database for novel targets to be tested in specific kidney disease models to advance with sex-specific treatment strategies.


The global burden of chronic kidney diseases is rapidly increasing and is projected to become the fifth most common cause of years of life lost worldwide by 2040. Sexual dimorphism in kidney diseases and transplantation is well known, yet sex-specific therapeutic strategies are still missing. One reason is the lack of knowledge due to the lack of inclusion of sex as a biological variable in study designs. This work aimed at identification of molecular signatures of male and female podocytes, gate-keepers of the glomerular filtration barrier. Like cardiomyocytes, podocytes are terminally differentiated cells which are highly susceptible towards pathological challenges. Podocytes are the decisive cell-type of the kidney to maintain the physiological blood-urine barrier, and disturbances of their homeostasis critically accelerate kidney function impairment. By help of a genomic mouse model, highly purified podocytes were obtained from male and female mice with and without pharmacological challenge of the mechanistic target of rapamycin (mTOR) signaling pathway which is known to be deregulated in major kidney diseases. Deep RNA sequencing, proteomics and metabolomics revealed strong intrinsic sex differences in the expression levels of mitochondrial, translation and structural transcripts, protein abundances and regulation of metabolic pathways which might fundamentally contribute to sex differences in kidney disease susceptibilities and progression. Remarkably, high number of previously reported kidney disease genes showed so far unknown intrinsic sexual dimorphism and/or different response patterns towards mTOR inhibition. Our work provides an in-depth database for novel targets to be tested in kidney disease models to advance with sex-specific treatment strategies.


Assuntos
Homeostase , Podócitos , Caracteres Sexuais , Sirolimo , Animais , Podócitos/efeitos dos fármacos , Podócitos/metabolismo , Masculino , Feminino , Sirolimo/farmacologia , Homeostase/efeitos dos fármacos , Camundongos , Serina-Treonina Quinases TOR/metabolismo , Transcriptoma , Inibidores de MTOR/farmacologia
15.
Int J Biol Sci ; 20(11): 4238-4257, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39247827

RESUMO

Squamous Cell Carcinoma (SCC) is a subtype of Non-Melanoma Skin Cancer, the most common group of malignancies worldwide. Photodynamic therapy (PDT) is a non-invasive treatment approved for specific subtypes of SCC. Some malignancies resist PDT, forming more aggressive tumors and multiple relapses. Thus, new approaches aimed at optimizing the response to PDT are needed. The mTORC1 inhibitor rapamycin, also known as Sirolimus (SRL), interferes with protein synthesis and cell metabolism. The use of SRL as an immunosuppressant is associated to lower rates of SCC in kidney-transplanted patients, which are frequently affected by this pathology. We have evaluated SRL pre-treatment efficacy to enhance the damage induced by PDT with Methyl 5-aminolevulinate in two different cutaneous SCC established cell lines (SCC13 and A431) in vitro and therapy sensitization in PDT-resistant cell lines. We tested for the first time the SRL + PDT combination in a SKH-1 mouse model of photocarcinogenesis, diminishing the frequency of lesions and restraining tumor growth. Molecular studies revealed that protoporphyrin IX and reactive oxygen species production induced by PDT were promoted by SRL pre-treatment. Lastly, SRL modifies the expression and intracellular location of NRF2, interfering with the downstream antioxidant response modulated by NQO1 and HO-1. In conclusion, we propose SRL as a potential adjuvant to enhance PDT efficacy for SCC treatment.


Assuntos
Carcinoma de Células Escamosas , Fator 2 Relacionado a NF-E2 , Fotoquimioterapia , Transdução de Sinais , Sirolimo , Neoplasias Cutâneas , Fator 2 Relacionado a NF-E2/metabolismo , Fotoquimioterapia/métodos , Animais , Camundongos , Sirolimo/farmacologia , Sirolimo/uso terapêutico , Humanos , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/patologia , Linhagem Celular Tumoral , Transdução de Sinais/efeitos dos fármacos , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Ácido Aminolevulínico/uso terapêutico , Ácido Aminolevulínico/farmacologia , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Espécies Reativas de Oxigênio/metabolismo , Feminino
16.
Bol Med Hosp Infant Mex ; 81(4): 232-244, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39236668

RESUMO

BACKGROUND: Vascular malformations (VaMs) are caused by errors in vascular morphogenesis. Diagnosis and treatment can be complex. Few specialized centers care for these patients, and limited literature exists regarding their characteristics and clinical course. The vascular anomalies clinic (VAC) at the Instituto Nacional de Pediatría (National Institute for Pediatrics) is a multidisciplinary team and has been a reference center for patients with VaMs since 2012. We sought to describe the characteristics of patients cared for at the VAC, types of VaMs, treatments used, and clinical course. METHODS: This was a descriptive, observational, retrospective, and cross-sectional study conducted from 2012 to 2022. RESULTS: We included 435 patients with VaMs; the median age of presentation was 1 month. The most frequent signs and symptoms were increased volume (97.2%), superficial color change (65.5%), and pain (43.3%). The most common VaMs were lymphatic (36.7%) and venolymphatic (18.3%). Sclerotherapy was the most frequent treatment (73.4%), followed by medical treatment with sirolimus (18.5%); response to both was excellent/good in > 85% of cases. CONCLUSION: In this retrospective study of children with VaMs, we found that low-flow malformations were the most common, and sclerotherapy and sirolimus were the most frequently used treatments. The therapeutic response was excellent/good in most cases.


INTRODUCCIÓN: Las malformaciones vasculares (MaV) son secundarias a errores en la morfogénesis vascular. El diagnóstico y tratamiento puede ser complejo. Existen pocos centros especializados en su atención y escasa literatura respecto a características y evolución clínica. La Clínica de Anomalías Vasculares (CAV) del Instituto Nacional de Pediatría es un equipo multidisciplinario y centro de referencia para estos pacientes desde 2012. Buscamos describir las características de los pacientes atendidos en la CAV, tipo de MaV, tratamiento y evolución clínica. MÉTODOS: Estudio descriptivo, observacional, retrospectivo y transversal del periodo 2012 al 2022. RESULTADOS: Se incluyeron 435 pacientes con MaV, con edad mediana de presentación de 1 mes de vida. Los síntomas y signos más reportados fueron aumento de volumen (97.2%), cambio en coloración de la piel (65.5%) y dolor (43.3%). Las MaV más comunes fueron linfáticas (36.7%), siguiéndoles las venolinfáticas (18.3%). La escleroterapia fue el tratamiento más frecuente (73.4%) y el tratamiento médico más utilizado fue sirolimus (18.5%), ambos con excelente/buena respuesta en > 85% de los pacientes. CONCLUSIONES: En este estudio retrospectivo de niños con MaV encontramos que las más frecuentes son de bajo flujo y el tratamiento más usado escleroterapia y sirolimus. La respuesta terapéutica de la mayoría fue excelente/buena.


Assuntos
Escleroterapia , Malformações Vasculares , Humanos , Estudos Retrospectivos , Malformações Vasculares/terapia , Malformações Vasculares/diagnóstico , Lactente , Masculino , Feminino , Estudos Transversais , Pré-Escolar , Criança , Recém-Nascido , Escleroterapia/métodos , Sirolimo/administração & dosagem , Adolescente , Resultado do Tratamento
17.
BMC Nephrol ; 25(1): 311, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39294598

RESUMO

OBJECTIVES: To evaluate long-term renal graft prognosis and the role of rapamycin from a single-center in China over a 30-year follow-up. METHODS: This study enrolled a total of 654 patients who underwent kidney transplantation between 1989 and 2020. The basic characteristics of the included patients were collected. Graft survival was described and compared using Kaplan-Meier curves (K-M curves). Both continuous and categorical variables were included in a multivariate Cox proportional-hazards model. Patients were divided into rapamycin-based quadruple immunosuppression regimen group (rapa group, n = 41) and conventional tacrolimus-based triple immunosuppression regimen group (control group, n = 218). The indication biopsy results of the two groups were further reviewed to compare the incidence of rejection, acute rejection, and banff score. RESULTS: The overall 5, 10, 15, 20-year graft survival rate of our center is 87.5%, 62.4%, 46.4% and 20.9%, respectively. The median survival time after surgery is 14 years. Multiple Cox regression analysis identified BMI (p = 0.035), dialysis type (p < 0.001), immunosuppressants (p < 0.01), urine albumen (p < 0.001), globulin (p = 0.041), and blood glucose (p = 0.002) as risk factors. The 20-year, 10-year and 5-year AUC is 0.78, 0.75 and 0.75. The combination of FK506 and rapamycin was further suggested by the model to effectively improve the graft prognosis (p < 0.01, HR = 0.763). The K-M curve showed that the long-term survival rate of renal grafts in the rapa group was significantly better than that in the conventional group (p < 0.001). In addition, indication biopsy records revealed a lower possibility of immune rejection in the rapa group than that in the conventional group (p < 0.001). Banff score indicated that rapa group had less vascular inflammation in the transplanted kidney. CONCLUSIONS: In this study, a 30-year follow-up was performed in a single center, and a total graft 20-year survival rate of 20.9% was reported. The prognostic model and subgroup analysis suggested that FK506 combined with rapamycin could effectively improve the prognosis of renal transplantation, which could be explained by reduced acute rejection and less vascular inflammation.


Assuntos
Rejeição de Enxerto , Sobrevivência de Enxerto , Imunossupressores , Transplante de Rim , Sirolimo , Tacrolimo , Humanos , Sirolimo/uso terapêutico , Masculino , Feminino , Imunossupressores/uso terapêutico , Adulto , Seguimentos , Pessoa de Meia-Idade , Rejeição de Enxerto/prevenção & controle , Tacrolimo/uso terapêutico , Estudos Retrospectivos , Fatores de Tempo , Modelos de Riscos Proporcionais , Quimioterapia Combinada
18.
Ren Fail ; 46(2): 2404486, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39287116

RESUMO

To investigate the clinical efficacy of sirolimus in treating children with refractory nephrotic syndrome, the clinical data for 22 children from the Children's Hospital of Hebei Province were analyzed retrospectively. There were 16 boys and six girls, and the treatment period was from September 2015 to April 2021. There were two patients with steroid-dependent nephrotic syndrome (SDNS), six patients with frequently relapsing nephrotic syndrome (FRNS), and 14 patients with steroid-resistant nephrotic syndrome (SRNS). All patients were defined as having refractory nephrotic syndrome. There were 12 patients (including nine SRNS patients and three FRNS patients) with minimal change disease (MCD), three patients (three SRNS patients) with focal segmental glomerular sclerosis (FSGS), one FRNS patient with mesangial proliferative glomerulonephritis (MsPGN), and six patients without a kidney biopsy. Compared with levels before sirolimus treatment, 24-hour urine protein (24-h UP), low-density lipoprotein cholesterol (LDL-C), urea (Ur) and serum creatinine (SCr) levels were significantly lower (all p < 0.05). Moreover, albumin (Alb) was significantly increased (p < 0.05), and there were no significant differences in total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), triglyceride (TG), immunoglobulin A (IgA), immunoglobulin G (IgG) or immunoglobulin M (IgM) (all p > 0.05) at the first follow-up. Sirolimus is effective as the first treatment of some children with refractory nephrotic syndrome, but its long-term efficacy and adverse reactions still require follow-up.


Assuntos
Imunossupressores , Síndrome Nefrótica , Sirolimo , Humanos , Síndrome Nefrótica/tratamento farmacológico , Masculino , Feminino , Sirolimo/uso terapêutico , Criança , Estudos Retrospectivos , Pré-Escolar , Imunossupressores/uso terapêutico , Adolescente , Resultado do Tratamento , Creatinina/sangue , Nefrose Lipoide/tratamento farmacológico , Glomerulosclerose Segmentar e Focal/tratamento farmacológico , LDL-Colesterol/sangue , Lactente , Rim/patologia , Proteinúria/tratamento farmacológico , Proteinúria/etiologia , China
19.
Tissue Eng Regen Med ; 21(7): 1049-1059, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39093548

RESUMO

BACKGROUND: Oxidative stress plays an important role in the skin aging process. Rapamycin has been shown to have anti-aging effects, but its role in oxidative senescence of skin cells remains unclear. The aim of this study was to explore the effect of rapamycin on oxidative stress-induced skin cell senescence and to illustrate the mechanism. METHODS: Primary human skin fibroblasts (HSFs) were extracted and a model of H2O2-induced oxidative senescence was constructed, and the effects of rapamycin on their value-added and migratory capacities were detected by CCK-8 and scratch assays. SA-ß-gal was utilized to detect senescence, oxidatively closely related factors were also assessed. Gene and protein expressions of senescence, oxidative, and autophagy were detected by western blotting and quantitative-PCR. The data were analyzed by one-way analysis of variance. RESULTS: Rapamycin (0.1 nmol/L for 48 h) promoted the proliferative and migration of H2O2-treated HSFs (p < 0.05), decreased senescent phenotypes SA-ß-gal staining and the expression of P53, and MMP-1 proteins, and increased the expression level of COL1A-1 (p < 0.001). Rapamycin also enhanced the activities of SOD and HO-1, and effectively removed intracellular ROS, MDA levels (p < 0.05), in addition, autophagy-related proteins and genes were significantly elevated after rapamycin pretreatment (p < 0.001). Rapamycin upregulated the autophagy pathway to exert its protective effects. CONCLUSION: Our findings indicate that rapamycin shields HSFs from H2O2-induced oxidative damage, the mechanism is related to the reduction of intracellular peroxidation and upregulation of autophagy pathway. Therefore, rapamycin has the potential to be useful in the investigation and prevention of signs of aging and oxidative stress.


Assuntos
Autofagia , Senescência Celular , Fibroblastos , Peróxido de Hidrogênio , Estresse Oxidativo , Sirolimo , Pele , Humanos , Sirolimo/farmacologia , Peróxido de Hidrogênio/farmacologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Senescência Celular/efeitos dos fármacos , Pele/efeitos dos fármacos , Pele/metabolismo , Autofagia/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Espécies Reativas de Oxigênio/metabolismo
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