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1.
Nano Lett ; 23(2): 476-490, 2023 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-36638236

RESUMO

Alzheimer's disease (AD) is a neurodegenerative disease with multifactorial pathogenesis. However, most current therapeutic approaches for AD target a single pathophysiological mechanism, generally resulting in unsatisfactory therapeutic outcomes. Recently, mesenchymal stem cell (MSC) therapy, which targets multiple pathological mechanisms of AD, has been explored as a novel treatment. However, the low brain retention efficiency of administered MSCs limits their therapeutic efficacy. In addition, autologous MSCs from AD patients may have poor therapeutic abilities. Here, we overcome these limitations by developing iron oxide nanoparticle (IONP)-incorporated human Wharton's jelly-derived MSCs (MSC-IONPs). IONPs promote therapeutic molecule expression in MSCs. Following intracerebroventricular injection, MSC-IONPs showed a higher brain retention efficiency under magnetic guidance. This potentiates the therapeutic efficacy of MSCs in murine models of AD. Furthermore, human Wharton's jelly-derived allogeneic MSCs may exhibit higher therapeutic abilities than those of autologous MSCs in aged AD patients. This strategy may pave the way for developing MSC therapies for AD.


Assuntos
Doença de Alzheimer , Células-Tronco Mesenquimais , Doenças Neurodegenerativas , Geleia de Wharton , Humanos , Camundongos , Animais , Idoso , Doença de Alzheimer/terapia , Doença de Alzheimer/metabolismo , Nanopartículas Magnéticas de Óxido de Ferro , Diferenciação Celular
2.
Adv Exp Med Biol ; 1395: 357-362, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36527662

RESUMO

Previously, anti-CD3 antibodies delivered intravenously have been known for their negative side effects. The experimental conditions for optimal liquid production are derived from the Fc-directed conjugation of anti-CD3 foralumab antibodies and magnetic nanoparticles (Ab-MNPs). The anti-CD3 antibodies are prepared for conjugation with MNPs using SiteClick antibody labelling kits. The successful conjugation of the Ab-MNPs is confirmed using a transmission electron microscopy (TEM) image and an energy dispersive spectroscopy (EDS) analysis. The average values ​​of the moving speed of MNPs and Ab-MNPs in phosphate buffer saline (PBS) were + 3.16 pix/frame and + 6.70 pix/frame in the x-axis, respectively. This implies that MNPs with CD3 antibodies attached to the surface through biocompatible ligand functional groups has better fluidity in PBS. Afterwards, a non-clinical animal testing for the flow characteristics of Ab-MNPs inside a blood vessel is carried out to observe the effects of Ab-MNP delivery through intravenous injection.


Assuntos
Nanopartículas de Magnetita , Animais , Nanopartículas de Magnetita/química , Magnetismo , Microscopia Eletrônica de Transmissão , Fenômenos Físicos , Anticorpos Monoclonais
3.
Small ; 17(32): e2101207, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34216428

RESUMO

Severe cardiac damage following myocardial infarction (MI) causes excessive inflammation, which sustains tissue damage and often induces adverse cardiac remodeling toward cardiac function impairment and heart failure. Timely resolution of post-MI inflammation may prevent cardiac remodeling and development of heart failure. Cell therapy approaches for MI are time-consuming and costly, and have shown marginal efficacy in clinical trials. Here, nanoparticles targeting the immune system to attenuate excessive inflammation in infarcted myocardium are presented. Liposomal nanoparticles loaded with MI antigens and rapamycin (L-Ag/R) enable effective induction of tolerogenic dendritic cells presenting the antigens and subsequent induction of antigen-specific regulatory T cells (Tregs). Impressively, intradermal injection of L-Ag/R into acute MI mice attenuates inflammation in the myocardium by inducing Tregs and an inflammatory-to-reparative macrophage polarization, inhibits adverse cardiac remodeling, and improves cardiac function. Nanoparticle-mediated blocking of excessive inflammation in infarcted myocardium may be an effective intervention to prevent the development of post-MI heart failure.


Assuntos
Insuficiência Cardíaca , Infarto do Miocárdio , Nanopartículas , Animais , Modelos Animais de Doenças , Insuficiência Cardíaca/prevenção & controle , Inflamação , Macrófagos , Camundongos , Camundongos Endogâmicos C57BL , Infarto do Miocárdio/complicações , Miocárdio
4.
Nano Lett ; 19(8): 5185-5193, 2019 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-31298024

RESUMO

Liposomes are clinically used as drug carriers for cancer therapy; however, unwanted leakage of the encapsulated anticancer drug and poor tumor-targeting efficiency of liposomes may generate toxic side effects on healthy cells and lead to failure of tumor eradication. To overcome these limitations, we functionalized liposomes with a photosensitizer (KillerRed, KR)-embedded cancer cell membrane (CCM). A lipid adjuvant was also embedded in the lipocomplex to promote the anticancer immune response. KR proteins were expressed on CCM and did not leak from the lipocomplex. Owing to the homotypic affinity of the CCM for the source cancer cells, the lipocomplex exhibited a 3.3-fold higher cancer-targeting efficiency in vivo than a control liposome. The liposome functionalized with KR-embedded CCM and lipid adjuvant generated cytotoxic reactive oxygen species in photodynamic therapy and effectively induced anticancer immune responses, inhibiting primary tumor growth and lung metastasis in homotypic tumor-bearing mice. Taken together, the lipocomplex technology may improve liposome-based cancer therapy.


Assuntos
Fatores Imunológicos/uso terapêutico , Lipossomos/uso terapêutico , Neoplasias/tratamento farmacológico , Fármacos Fotossensibilizantes/uso terapêutico , Animais , Linhagem Celular Tumoral , Membrana Celular/patologia , Proteínas de Fluorescência Verde/uso terapêutico , Humanos , Camundongos , Metástase Neoplásica/tratamento farmacológico , Metástase Neoplásica/patologia , Neoplasias/patologia
5.
Nano Lett ; 18(8): 4965-4975, 2018 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-29995418

RESUMO

Human mesenchymal stem cell (hMSC)-derived exosomes have been spotlighted as a promising therapeutic agent for cell-free regenerative medicine. However, poor organ-targeting ability and insufficient therapeutic efficacy of systemically injected hMSC-exosomes were identified as critical limitations for their further applications. Therefore, in this study we fabricated iron oxide nanoparticle (IONP)-incorporated exosome-mimetic nanovesicles (NV-IONP) from IONP-treated hMSCs and evaluated their therapeutic efficacy in a clinically relevant model for spinal cord injury. Compared to exosome-mimetic nanovesicles (NV) prepared from untreated hMSCs, NV-IONP not only contained IONPs which act as a magnet-guided navigation tool but also carried greater amounts of therapeutic growth factors that can be delivered to the target cells. The increased amounts of therapeutic growth factors inside NV-IONP were attributed to IONPs that are slowly ionized to iron ions which activate the JNK and c-Jun signaling cascades in hMSCs. In vivo systemic injection of NV-IONP with magnetic guidance significantly increased the amount of NV-IONP accumulating in the injured spinal cord. Accumulated NV-IONP enhanced blood vessel formation, attenuated inflammation and apoptosis in the injured spinal cord, and consequently improved spinal cord function. Taken together, these findings highlight the development of therapeutic efficacy-potentiated extracellular nanovesicles and demonstrate their feasibility for repairing injured spinal cord.


Assuntos
Nanopartículas de Magnetita/química , Células-Tronco Mesenquimais/química , Traumatismos da Medula Espinal/terapia , Animais , Apoptose , Materiais Biomiméticos , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Exossomos/química , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/química , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/ultraestrutura , Camundongos , Neovascularização Fisiológica , Células PC12 , Ratos , Transdução de Sinais , Traumatismos da Medula Espinal/patologia
6.
ACS Cent Sci ; 10(7): 1371-1382, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39071065

RESUMO

Radiotherapy is commonly used to treat cancer, and localized energy deposited by radiotherapy has the potential to chemically uncage prodrugs; however, it has been challenging to demonstrate prodrug activation that is both sustained in vivo and truly localized to tumors without affecting off-target tissues. To address this, we developed a series of novel phenyl-azide-caged, radiation-activated chemotherapy drug-conjugates alongside a computational framework for understanding corresponding pharmacokinetic and pharmacodynamic (PK/PD) behaviors. We especially focused on an albumin-bound prodrug of monomethyl auristatin E (MMAE) and found it blocked tumor growth in mice, delivered a 130-fold greater amount of activated drug to irradiated tumor versus unirradiated tissue, was 7.5-fold more efficient than a non albumin-bound prodrug, and showed no appreciable toxicity compared to free or cathepsin-activatable drugs. These data guided computational modeling of drug action, which indicated that extended pharmacokinetics can improve localized and cumulative drug activation, especially for payloads with low vascular permeability and diffusivity and particularly in patients receiving daily treatments of conventional radiotherapy for weeks. This work thus offers a quantitative PK/PD framework and proof-of-principle experimental demonstration of how extending prodrug circulation can improve its localized activity in vivo.

7.
Behav Sci (Basel) ; 14(6)2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38920790

RESUMO

This study explored the positive effects of a six-week Social-Emotional and Ethical Learning® (SEE Learning) program on resilience and social and emotional competences, adapted for elementary students in Daegu, South Korea, a region strongly affected by the first outbreak of COVID-19. A total of 348 third- and fourth-grade students from 15 elementary schools participated, and the curriculum was tailored, emphasizing key areas such as resilience, attention, kindness, attention training, and compassion. Repeated measures analysis of variance (RMANOVA) tests showed statistically significant improvements between pre- and post-tests in resilience and its subscales, including self-efficacy, tolerance of negative affect, positive support relations, power of control, and spontaneity, as well as in social and emotional competencies, including emotional regulation, social skills, empathy, and social tendencies. Despite a lack of maintenance in all areas, at follow-up, the mean scores for self-efficacy, tolerance of negative affect, and positive support relations, as well as emotional regulation, social skills, empathy, and social tendency, remained higher than pre-test levels, suggesting some lasting benefits. The findings underscore the potential of the SEE Learning program integrated with resilience, mindfulness, compassion, and ethical practices to enhance students' resilience and social and emotional well-being. This study contributes to the growing body of evidence supporting the use of mindfulness and compassion-based SEL programs to mitigate the adverse effects of traumatic events on children's mental health.

8.
Adv Mater ; 36(23): e2312326, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38389502

RESUMO

Clinical treatment of cancer commonly incorporates X-ray radiation therapy (XRT), and developing spatially precise radiation-activatable drug delivery strategies may improve XRT efficacy while limiting off-target toxicities associated with systemically administered drugs. Nevertheless, achieving this has been challenging thus far because strategies typically rely on radical species with short lifespans, and the inherent nature of hypoxic and acidic tumor microenvironments may encourage spatially heterogeneous effects. It is hypothesized that the challenge could be bypassed by using scintillating nanoparticles that emit light upon X-ray absorption, locally forming therapeutic drug depots in tumor tissues. Thus a nanoparticle platform (Scintillating nanoparticle Drug Depot; SciDD) that enables the local release of cytotoxic payloads only after activation by XRT is developed, thereby limiting off-target toxicity. As a proof-of-principle, SciDD is used to deliver a microtubule-destabilizing payload MMAE (monomethyl auristatin E). With as little as a 2 Gy local irradiation to tumors, MMAE payloads are released effectively to kill tumor cells. XRT-mediated drug release is demonstrated in multiple mouse cancer models and showed efficacy over XRT alone (p < 0.0001). This work shows that SciDD can act as a local drug depot with spatiotemporally controlled release of cancer therapeutics.


Assuntos
Nanopartículas , Animais , Nanopartículas/química , Camundongos , Humanos , Linhagem Celular Tumoral , Liberação Controlada de Fármacos , Preparações de Ação Retardada/química , Oligopeptídeos/química , Antineoplásicos/química , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Portadores de Fármacos/química
9.
J Phys Ther Sci ; 25(9): 1079-81, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24259919

RESUMO

[Purpose] The purpose of the present study was to investigate the effect of TENS applied to the skin overlying the bellies of the gastrocnemius muscles of the lower limbs on balance and plantar pressure of healthy adults. [Subjects and Methods] Twenty-eight healthy college students were the subjects of this study. Adhesive transcutaneous electrical nerve stimulation (TENS) electrodes were attached to the medial and lateral belly of the gastrocnemius muscle. Before and after the application of the TENS, subjects' balance ability and maximum plantar pressure were measured and compared. [Results] The scores improved in the balance tests, including the fall risk test and the stability limit test, after the application of TENS, and a statistically significant difference was noted in the stability limit test. The maximum plantar pressure after the application of TENS decreased except beneath the big toe, and statistically significant difference was found under the forefoot. [Conclusion] The results of present study suggest that TENS applied to the skin overlying gastrocnemius muscles is useful strategy that improves the balance ability of healthy adults.

10.
Exp Mol Med ; 55(3): 541-554, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36854774

RESUMO

The development of therapeutic cancer vaccines (TCVs) that provide clinical benefits is challenging mainly due to difficulties in identifying immunogenic tumor antigens and effectively inducing antitumor immunity. Furthermore, there is an urgent need for personalized TCVs because only a limited number of tumor antigens are shared among cancer patients. Several autologous nanovaccines that do not require the identification of immunogenic tumor antigens have been proposed as personalized TCVs. However, these nanovaccines generally require exogenous adjuvants (e.g., Toll-like receptor agonists) to improve vaccine immunogenicity, which raises safety concerns. Here, we present senescent cancer cell-derived nanovesicle (SCCNV) as a personalized TCV that provides patient-specific tumor antigens and improved vaccine immunogenicity without the use of exogenous adjuvants. SCCNVs are prepared by inducing senescence in cancer cells ex vivo and subsequently extruding the senescent cancer cells through nanoporous membranes. In the clinical setting, SCCNVs can be prepared from autologous cancer cells from the blood of liquid tumor patients or from tumors surgically removed from solid cancer patients. SCCNVs also contain interferon-γ and tumor necrosis factor-α, which are expressed during senescence. These endogenous cytokines act as adjuvants and enhance vaccine immunogenicity, avoiding the need for exogenous adjuvants. Intradermally injected SCCNVs effectively activate dendritic cells and tumor-specific T cells and inhibit primary and metastatic tumor growth and tumor recurrence. SCCNV therapy showed an efficacy similar to that of immune checkpoint blockade (ICB) therapy and synergized with ICB. SCCNVs, which can be prepared using a simple and facile procedure, show potential as personalized TCVs.


Assuntos
Vacinas Anticâncer , Neoplasias , Humanos , Vacinas Anticâncer/uso terapêutico , Neoplasias/tratamento farmacológico , Antígenos de Neoplasias , Adjuvantes Imunológicos
11.
Clin Cancer Res ; 29(17): 3457-3470, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37289199

RESUMO

PURPOSE: Oncogene-driven macropinocytosis fuels nutrient scavenging in some cancer types, yet whether this occurs in thyroid cancers with prominent MAPK-ERK and PI3K pathway mutations remains unclear. We hypothesized that understanding links between thyroid cancer signaling and macropinocytosis might uncover new therapeutic strategies. EXPERIMENTAL DESIGN: Macropinocytosis was assessed across cells derived from papillary thyroid cancer (PTC), follicular thyroid cancer (FTC), non-malignant follicular thyroid, and aggressive anaplastic thyroid cancer (ATC), by imaging fluorescent dextran and serum albumin. The impacts of ectopic BRAFV600E and mutant RAS, genetic PTEN silencing, and inhibitors targeting RET, BRAF, and MEK kinases were quantified. BrafV600E p53-/- ATC tumors in immunocompetent mice were used to measure efficacy of an albumin-drug conjugate comprising microtubule-destabilizing monomethyl auristatin E (MMAE) linked to serum albumin via a cathepsin-cleavable peptide (Alb-vc-MMAE). RESULTS: FTC and ATC cells showed greater macropinocytosis than non-malignant and PTC cells. ATC tumors accumulated albumin at 8.8% injected dose per gram tissue. Alb-vc-MMAE, but not MMAE alone, reduced tumor size by >90% (P < 0.01). ATC macropinocytosis depended on MAPK/ERK activity and nutrient signaling, and increased by up to 230% with metformin, phenformin, or inhibition of IGF1Ri in monoculture but not in vivo. Macrophages also accumulated albumin and express the cognate IGF1R ligand, IGF1, which reduced ATC responsiveness to IGF1Ri. CONCLUSIONS: These findings identify regulated oncogene-driven macropinocytosis in thyroid cancers and demonstrate the potential of designing albumin-bound drugs to efficiently treat them.


Assuntos
Carcinoma Anaplásico da Tireoide , Neoplasias da Glândula Tireoide , Camundongos , Animais , Fosfatidilinositol 3-Quinases/genética , Mutação , Proteínas Proto-Oncogênicas B-raf , Neoplasias da Glândula Tireoide/tratamento farmacológico , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/metabolismo , Carcinoma Anaplásico da Tireoide/tratamento farmacológico , Carcinoma Anaplásico da Tireoide/genética , Oncogenes , Câncer Papilífero da Tireoide/genética , Albumina Sérica/genética , Albumina Sérica/uso terapêutico
12.
Adv Mater ; 35(3): e2207719, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36329674

RESUMO

Alzheimer's disease (AD), the most common cause of dementia, is a complex condition characterized by multiple pathophysiological mechanisms including amyloid-ß (Aß) plaque accumulation and neuroinflammation in the brain. The current immunotherapy approaches, such as anti-Aß monoclonal antibody (mAb) therapy, Aß vaccines, and adoptive regulatory T (Treg) cell transfer, target a single pathophysiological mechanism, which may lead to unsatisfactory therapeutic efficacy. Furthermore, Aß vaccines often induce T helper 1 (Th1) cell-mediated inflammatory responses. Here, a nanovaccine composed of lipid nanoparticles loaded with Aß peptides and rapamycin is developed, which targets multiple pathophysiological mechanisms, exhibits the combined effects of anti-Aß antibody therapy and adoptive Aß-specific Treg cell transfer, and can overcome the limitations of current immunotherapy approaches for AD. The Nanovaccine effectively delivers rapamycin and Aß peptides to dendritic cells, produces both anti-Aß antibodies and Aß-specific Treg cells, removes Aß plaques in the brain, alleviates neuroinflammation, prevents Th1 cell-mediated excessive immune responses, and inhibits cognitive impairment in mice. The nanovaccine shows higher efficacy in cognitive recovery than an Aß vaccine. Unlike anti-Aß mAb therapy and adoptive Treg cell transfer, both of which require complicated and costly manufacturing processes, the nanovaccine is easy-to-prepare and cost-effective. The nanovaccines can represent a novel treatment option for AD.


Assuntos
Doença de Alzheimer , Vacinas , Camundongos , Animais , Linfócitos T Reguladores , Doenças Neuroinflamatórias , Camundongos Transgênicos , Peptídeos beta-Amiloides , Anticorpos Monoclonais , Modelos Animais de Doenças
13.
Nat Nanotechnol ; 18(12): 1502-1514, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37884660

RESUMO

Commencing with the breakdown of immune tolerance, multiple pathogenic factors, including synovial inflammation and harmful cytokines, are conjointly involved in the progression of rheumatoid arthritis. Intervening to mitigate some of these factors can bring a short-term therapeutic effect, but other unresolved factors will continue to aggravate the disease. Here we developed a ceria nanoparticle-immobilized mesenchymal stem cell nanovesicle hybrid system to address multiple factors in rheumatoid arthritis. Each component of this nanohybrid works individually and also synergistically, resulting in comprehensive treatment. Alleviation of inflammation and modulation of the tissue environment into an immunotolerant-favourable state are combined to recover the immune system by bridging innate and adaptive immunity. The therapy is shown to successfully treat and prevent rheumatoid arthritis by relieving the main symptoms and also by restoring the immune system through the induction of regulatory T cells in a mouse model of collagen-induced arthritis.


Assuntos
Artrite Experimental , Artrite Reumatoide , Camundongos , Animais , Artrite Experimental/tratamento farmacológico , Artrite Reumatoide/tratamento farmacológico , Imunidade Adaptativa , Citocinas , Inflamação
14.
Artigo em Inglês | MEDLINE | ID: mdl-36612770

RESUMO

This study investigated the effects of a multi-access, metaverse-based early onset schizophrenia nursing simulation program based on Raskin and Rogers' person-centered therapy. The program's effectiveness was tested using a nonequivalent control group pre-test/post-test design. A quasi-experimental simulation study with both pre- and post-test designs was adopted. The experimental group (n = 29) used the simulation program, whereas the control group (n = 29) received only an online lecture on schizophrenia nursing. Changes in scores among experimental and control groups were compared using independent t-tests and analyses of covariance with PASW SPSS-WIN 27.0. Post-intervention, the knowledge regarding patients with early onset schizophrenia, critical thinking ability, and the ability to facilitate communication increased significantly in the experimental group compared with the control group. The nursing simulation program for children with early onset schizophrenia using a metaverse improved nursing students' knowledge, critical thinking ability, and ability to facilitate communication. This training method should be adapted without spatiotemporal constraints by partially supplementing clinical and simulation-based practice. In clinical nursing training, metaverse technical limitations should be identified, and training topics should be selected. Employing EduTech in a metaverse environment can provide clinical education to nurses in psychiatric wards and improve therapeutic communication with their psychiatric patients.


Assuntos
Bacharelado em Enfermagem , Esquizofrenia , Estudantes de Enfermagem , Criança , Humanos , Bacharelado em Enfermagem/métodos , Competência Clínica , Pensamento , Estudantes de Enfermagem/psicologia
15.
Adv Mater ; 34(9): e2106516, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34962660

RESUMO

Despite the clinically proven efficacies of immune checkpoint blockades, including anti-cytotoxic T lymphocyte-associated protein 4 antibody (αCTLA-4), the low response rate and immune-related adverse events (irAEs) in cancer patients represent major drawbacks of the therapy. These drawbacks of αCTLA-4 therapy are mainly due to the suboptimal activation of tumor-specific cytotoxic T lymphocytes (CTLs) and the systemic nonspecific activation of T cells. To overcome such drawbacks, αCTLA-4 is delivered by dendritic cell-derived nanovesicles presenting tumor antigens (DCNV-TAs) that exclusively interact with tumor-specific T cells, leading to selective activation of tumor-specific CTLs. Compared to conventional αCTLA-4 therapy, treatment with αCTLA-4-conjugated DCNV-TAs significantly inhibits tumor growth and reduces irAEs in syngeneic tumor-bearing mice. This study demonstrates that the spatiotemporal presentation of both αCTLA-4 and tumor antigens enables selective activation of tumor-specific T cells and potentiates the antitumor efficacy of αCTLA-4 without inducing systemic irAEs.


Assuntos
Inibidores de Checkpoint Imunológico , Neoplasias , Animais , Antígenos de Neoplasias , Humanos , Imunoterapia , Camundongos , Neoplasias/tratamento farmacológico , Linfócitos T Citotóxicos
16.
ACS Biomater Sci Eng ; 8(5): 1921-1929, 2022 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-35416659

RESUMO

The vast majority of drug-eluting stents (DES) elute either sirolimus or one of its analogues. While limus drugs stymie vascular smooth muscle cell (VSMC) proliferation to prevent in-stent restenosis, their antiproliferative nature is indiscriminate and limits healing of the endothelium in stented vessels, increasing the risk of late-stent thrombosis. Oxidative stress, which is associated with vascular injury from stent implantation, can induce VSMCs to undergo senescence, and senescent VSMCs can produce pro-inflammatory cytokines capable of inducing proliferation of neighboring nonsenescent VSMCs. We explored the potential of senolytic therapy, which involves the selective elimination of senescent cells, in the form of a senolytic-eluting stent (SES) for interventional cardiology. Oxidative stress was modeled in vitro by exposing VSMCs to H2O2, and H2O2-mediated senescence was evaluated by cytochemical staining of senescence-associated ß-galactosidase activity and qRT-PCR. Quiescent VSMCs were then treated with the conditioned medium (CM) of H2O2-treated VSMCs. Proliferative effects of CM were analyzed by staining for proliferating cell nuclear antigen. Senolytic effects of the first-generation senolytic ABT263 were observed in vitro, and the effects of ABT263 on endothelial cells were also investigated through an in vitro re-endothelialization assay. SESs were prepared by dip coating. Iliofemoral arteries of hypercholesteremic rabbits were implanted with SES, everolimus-eluting stents (EESs), or bare-metal stents (BMSs), and the area of stenosis was measured 4 weeks post-implantation using optical coherence tomography. We found that a portion of H2O2-treated VSMCs underwent senescence, and that CM of H2O2-treated senescent VSMCs triggered the proliferation of quiescent VSMCs. ABT263 reverted H2O2-mediated senescence and the proliferative capacity of senescent VSMC CM. Unlike everolimus, ABT263 did not affect endothelial cell migration and/or proliferation. SES, but not EES, significantly reduced stenosis area in vivo compared with bare-metal stents (BMSs). This study shows the potential of SES as an alternative to current forms of DES.


Assuntos
Reestenose Coronária , Stents Farmacológicos , Animais , Constrição Patológica , Reestenose Coronária/prevenção & controle , Stents Farmacológicos/efeitos adversos , Células Endoteliais , Everolimo/farmacologia , Peróxido de Hidrogênio/farmacologia , Coelhos , Senoterapia , Stents
17.
Adv Healthc Mater ; 11(2): e2101483, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34699690

RESUMO

Intervertebral disc (IVD) degeneration (IVDD) is a leading cause of chronic low back pain. There is a strong clinical demand for more effective treatments for IVDD as conventional treatments provide only symptomatic relief rather than arresting IVDD progression. This study shows that senolytic therapy with local drug delivery can inhibit IVDD and restore IVD integrity. ABT263, a senolytic drug, is loaded in poly(lactic-co-glycolic acid) nanoparticles (PLGA-ABT) and intradiscally administered into injury-induced IVDD rat models. The single intradiscal injection of PLGA-ABT may enable local delivery of the drug to avascular IVD, prevention of potential systemic toxicity caused by systemic administration of senolytic drug, and morbidity caused by repetitive injections of free drug into the IVD. The strategy results in the selective elimination of senescent cells from the degenerative IVD, reduces expressions of pro-inflammatory cytokines and matrix proteases in the IVD, inhibits progression of IVDD, and even restores the IVD structure. This study demonstrates for the first time that local delivery of senolytic drug can effectively treat senescence-associated IVDD. This approach can be extended to treat other types of senescence-associated degenerative diseases.


Assuntos
Degeneração do Disco Intervertebral , Disco Intervertebral , Animais , Sistemas de Liberação de Medicamentos , Disco Intervertebral/metabolismo , Degeneração do Disco Intervertebral/tratamento farmacológico , Degeneração do Disco Intervertebral/metabolismo , Preparações Farmacêuticas , Ratos , Senoterapia
18.
Sensors (Basel) ; 11(4): 3595-610, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22163811

RESUMO

Cloud computing is a new information technology trend that moves computing and data away from desktops and portable PCs into large data centers. The basic principle of cloud computing is to deliver applications as services over the Internet as well as infrastructure. A cloud is a type of parallel and distributed system consisting of a collection of inter-connected and virtualized computers that are dynamically provisioned and presented as one or more unified computing resources. The large-scale distributed applications on a cloud require adaptive service-based software, which has the capability of monitoring system status changes, analyzing the monitored information, and adapting its service configuration while considering tradeoffs among multiple QoS features simultaneously. In this paper, we design and develop a Run-Time Monitor (RTM) which is a system software to monitor the application behavior at run-time, analyze the collected information, and optimize cloud computing resources for multi-core architectures. RTM monitors application software through library instrumentation as well as underlying hardware through a performance counter optimizing its computing configuration based on the analyzed data.


Assuntos
Computadores , Armazenamento e Recuperação da Informação/métodos , Software , Humanos , Internet
19.
Tissue Eng Regen Med ; 18(5): 841-850, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34003467

RESUMO

BACKGROUND: Ferroptosis is an iron-dependent, non-apoptotic programmed cell death. Cellular senescence contributes to aging and various age-related diseases through the expression of a senescence-associated secretory phenotype (SASP). Senescent cells are often resistant to ferroptosis via increased ferritin and impaired ferritinophagy. In this study, we investigated whether treatment with JQ1 could remove senescent cells by inducing ferroptosis. METHODS: Senescence of human dermal fibroblasts was induced in vitro by treating the cells with bleomycin. The senolytic effects of JQ1 were evaluated using a SA-ß gal assay, annexin V analysis, cell counting kit-8 assay, and qRT-PCR. Ferroptosis following JQ1 treatment was evaluated with qRT-PCR and BODIPY staining. RESULTS: At a certain range of JQ1 concentrations, JQ1 treatment reduced the viability of bleomycin-treated cells (senescent cells) but did not reduce that of untreated cells (non-senescent cells), indicating that JQ1 treatment can selectively eliminate senescent cells. JQ1 treatment also decreased SASP expression only in senescent cells. Subsequently, JQ1 treatment reduced the expression of ferroptosis-resistance genes in senescent cells. JQ1 treatment induced lipid peroxidation in senescent cells but not in non-senescent cells. CONCLUSION: The data indicate that JQ1 can eliminate senescent cells via ferroptosis. This study suggests ferroptosis as a new mechanism of senolytic therapy.


Assuntos
Ferroptose , Preparações Farmacêuticas , Envelhecimento , Senescência Celular , Fibroblastos , Humanos
20.
Adv Mater ; 33(33): e2101110, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34235790

RESUMO

Although T-cell therapy is a remarkable breakthrough in cancer immunotherapy, the therapeutic efficacy is limited for solid tumors. A major cause of the low efficacy is T-cell exhaustion by immunosuppressive mechanisms of solid tumors, which are mainly mediated by programmed death-ligand 1 (PD-L1) and transforming growth factor-beta (TGF-ß). Herein, T-cell-derived nanovesicles (TCNVs) produced by the serial extrusion of cytotoxic T cells through membranes with micro-/nanosized pores that inhibit T-cell exhaustion and exhibit antitumoral activity maintained in the immunosuppressive tumor microenvironment (TME) are presented. TCNVs, which have programmed cell death protein 1 and TGF-ß receptor on their surface, block PD-L1 on cancer cells and scavenge TGF-ß in the immunosuppressive TME, thereby preventing cytotoxic-T-cell exhaustion. In addition, TCNVs directly kill cancer cells via granzyme B delivery. TCNVs successfully suppress tumor growth in syngeneic-solid-tumor-bearing mice. Taken together, TCNV offers an effective cancer immunotherapy strategy to overcome the tumor's immunosuppressive mechanisms.


Assuntos
Granzimas/química , Imunossupressores/química , Imunoterapia/métodos , Nanocápsulas/química , Neoplasias/terapia , Linfócitos T Citotóxicos/química , Animais , Antígeno B7-H1/metabolismo , Linhagem Celular Tumoral , Granzimas/metabolismo , Humanos , Imunossupressores/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Camundongos , Neoplasias Experimentais , Receptor de Morte Celular Programada 1/metabolismo , Transdução de Sinais , Microambiente Tumoral/efeitos dos fármacos
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