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1.
Vasc Health Risk Manag ; 17: 103-109, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33790567

RESUMO

Introduction: Smoking can cause vascular damage in the form of an inflammatory reaction characterized by endothelial activation. Endothelial activation forms a pathological adaptation pattern so that it can induce the atherogenesis process. Several markers, such as E-selectin, platelet-derived micro particles (PMPs) and hematopoietic stem cell (HSC) can identify the activation of endothelial in circulating blood. Therefore, the deviation of vascular adaptation due to smoking can be detected early through the feedback mechanism between E-selectin, PMPs, and HSC. Purpose: This study aims to analyze the initial picture of the negative impact of smoking on vascular adaptation by measuring E-selectin, PMPs, and HSC in the peripheral blood circulation. Participant criteria and methods: Peripheral blood samples (5 mL) were taken from each participant, both the smoking group (n = 30) and the non-smoker group (n = 31) to obtain peripheral blood mononuclear cells (PBMNC). PBMNC was isolated using ficoll-based gradient centrifugation. The flow cytometry assay method used to measure the E-selectin, PMPs and hematopoietic stem cells. Results: The mean of circulating E-selectin in smokers was higher than that of non-smokers. On the other hand, the average number of PMPs and HSCs in smokers was lower than non-smokers. Conclusion: Smoking increases the risk of accelerated vascular block formation, as indicated by an increase in the amount of circulating E-selectin. The increase in E-selectin in the blood vessels mediates the increased adhesion of PMPs in the vascular area so that the number of circulating PMPs in smokers decreases. The decrease in circulating PMPs decreases the signal of vascular repair, which is characterized by a decline in the number of HSCs.


Assuntos
Plaquetas/metabolismo , Doenças Cardiovasculares/diagnóstico , Micropartículas Derivadas de Células/metabolismo , Selectina E/sangue , Células Endoteliais/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Fumantes , Fumar/efeitos adversos , Adulto , Biomarcadores/sangue , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/etiologia , Estudos de Casos e Controles , Estudos Transversais , Diagnóstico Precoce , Células Endoteliais/patologia , Humanos , não Fumantes , Valor Preditivo dos Testes , Fumar/sangue , Fatores de Tempo
2.
Methods Mol Biol ; 2291: 177-205, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33704754

RESUMO

Outer membrane vesicles (OMVs), nanoparticles released by Shiga toxin-producing Escherichia coli (STEC), have been identified as novel efficient virulence tools of these pathogens. STEC O157 OMVs carry a cocktail of virulence factors including Shiga toxin 2a (Stx2a), cytolethal distending toxin V (CdtV), EHEC hemolysin, flagellin, and lipopolysaccharide. OMVs are taken up by human intestinal epithelial and microvascular endothelial cells, the major targets during STEC infection, and deliver the virulence factors into host cells. There the toxins separate from OMVs and are trafficked via different pathways to their target compartments, i.e., the cytosol (Stx2a-A subunit), nucleus (CdtV-B subunit), and mitochondria (EHEC hemolysin). This leads to a toxin-specific host cell injury and ultimately apoptotic cell death. Besides their cytotoxic effects, STEC OMVs trigger an inflammatory response via their lipopolysaccharide and flagellin components. In this chapter, we describe methods for the isolation and purification of STEC OMVs, for the detection of OMV-associated virulence factors, and for the analysis of OMV interactions with host cells including OMV cellular uptake and intracellular trafficking of OMVs and OMV-delivered toxins.


Assuntos
Toxinas Bacterianas/metabolismo , Micropartículas Derivadas de Células/metabolismo , Células Endoteliais/metabolismo , Escherichia coli O157 , Toxina Shiga II/metabolismo , Fatores de Virulência/metabolismo , Células Endoteliais/microbiologia , Células Endoteliais/patologia , Escherichia coli O157/metabolismo , Escherichia coli O157/patogenicidade , Humanos
3.
Methods Mol Biol ; 2291: 207-228, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33704755

RESUMO

Microvesicles are shed from cell surfaces during infectious or inflammatory conditions and may contribute to the pathogenesis of disease. During Shiga toxin-producing Escherichia coli (STEC) infection, microvesicles are released from blood cells. These microvesicles play a part in inflammation, thrombosis, hemolysis, and the transfer of the main virulence factor of STEC strains, Shiga toxin, to target organ cells. This chapter describes how to isolate blood cell- and cell culture-derived microvesicles from plasma or cell culture medium, respectively, and how to characterize these microvesicles by various methods, with special focus on Shiga toxin-associated microvesicles.


Assuntos
Micropartículas Derivadas de Células , Proteínas de Escherichia coli , Toxina Shiga , Escherichia coli Shiga Toxigênica , Fatores de Virulência , Animais , Micropartículas Derivadas de Células/química , Micropartículas Derivadas de Células/metabolismo , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/metabolismo , Humanos , Toxina Shiga/química , Toxina Shiga/metabolismo , Escherichia coli Shiga Toxigênica/química , Escherichia coli Shiga Toxigênica/metabolismo , Fatores de Virulência/química , Fatores de Virulência/metabolismo
4.
Clin Appl Thromb Hemost ; 27: 1076029620982374, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33571008

RESUMO

Mechanically assisted circulation (MAC) sustains the blood circulation in the body of a patients undergoing cardiac surgery with cardiopulmonary bypass (CPB) or on ventricular assistance with a ventricular assist device (VAD) or on extracorporeal membrane oxygenation (ECMO) with a pump-oxygenator system. While MAC provides short-term (days to weeks) support and long-term (months to years) for the heart and/or lungs, the blood is inevitably exposed to non-physiological shear stress (NPSS) due to mechanical pumping action and in contact with artificial surfaces. NPSS is well known to cause blood damage and functional alterations of blood cells. In this review, we discussed shear-induced platelet adhesion, platelet aggregation, platelet receptor shedding, and platelet apoptosis, shear-induced acquired von Willebrand syndrome (AVWS), shear-induced hemolysis and microparticle formation during MAC. These alterations are associated with perioperative bleeding and thrombotic events, morbidity and mortality, and quality of life in MCS patients. Understanding the mechanism of shear-induce hemostatic disorders will help us develop low-shear-stress devices and select more effective treatments for better clinical outcomes.


Assuntos
Plaquetas/metabolismo , Ponte Cardiopulmonar/instrumentação , Oxigenação por Membrana Extracorpórea/instrumentação , Coração Auxiliar , Transtornos Hemostáticos/etiologia , Oxigenadores de Membrana , Implantação de Prótese/instrumentação , Animais , Plaquetas/patologia , Ponte Cardiopulmonar/efeitos adversos , Micropartículas Derivadas de Células/metabolismo , Micropartículas Derivadas de Células/patologia , Oxigenação por Membrana Extracorpórea/efeitos adversos , Hemólise , Transtornos Hemostáticos/sangue , Humanos , Ativação Plaquetária , Desenho de Prótese , Implantação de Prótese/efeitos adversos , Medição de Risco , Fatores de Risco , Estresse Mecânico , Resultado do Tratamento
5.
PLoS One ; 16(2): e0246806, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33617530

RESUMO

BACKGROUND AND AIM: The study aimed to determine whether the MPs levels and platelet activation are affected by the COVID-19 infection in both malignant and non-malignant patients compared to healthy individuals and define their contribution to the COVID-19 associated coagulopathy and the relation of these MPs to other hematologic parameters. PATIENTS AND METHODS: We recruited 23 malignant patients with reverse transcription polymerase chain reaction (RT-PCR) positive COVID-19, also, 19 COVID-19 non-malignant patients, and 20 healthy volunteers were also enrolled for comparison. Blood samples were collected from patients and healthy donors into 5 mL vacutainer tube containing 3.5% buffered sodium citrate solution for measurement of total microparticles (TMPs), platelet microparticles (PMPs), endothelial microparticles (EMPs), CD62 activated platelets, and CD41 platelet marker. RESULTS: COVID-19 malignant patients had significantly lower hemoglobin and platelets compared to COVID non-malignant ones, while they had significantly higher C-reactive protein, LDH, AST, Albunim, creatinine, and prognostic index (PI) compared to COVID-19 non-malignant patients. significant accumulations of TMPs, PMPs, EMPs, and activated platelets in COVID-19 affected patients compared to healthy controls. TMPs, and EMPs were significantly accumulated in COVID-19 malignant compared to COVID-19 non-malignant patients with no significant difference in PMPs between both. CONCLUSION: Circulating MPs and activated platelets may be promising novel prognostic biomarkers capable of identifying potentially severe COVID-19 patients who require immediate care especially in cancer patients.


Assuntos
Plaquetas/citologia , Micropartículas Derivadas de Células/metabolismo , Neoplasias/epidemiologia , Ativação Plaquetária , Adulto , Biomarcadores/sangue , Coagulação Sanguínea , Feminino , Hemoglobinas/análise , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico
6.
Life Sci ; 271: 119149, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33549596

RESUMO

Drug resistance in cancer, still poses therapeutic challenges and tumor microenvironment plays a critical role in it. Microvesicles (MVs) are effective transporters of the molecular information between cells and regulate the tumor microenvironment. They contribute to the drug resistance by transferring functional molecules between cells. Herein we report the effects of liver cancer cell-secreted MVs on sorafenib resistance in liver cancer cells HepG2 and Huh7 both in vitro and in vivo. In our study, these cancer cell-secreted MVs affected the anti-proliferative effect of sorafenib in a dose- and time-dependent manner and also inhibited the sorafenib induced apoptosis in vitro. Further, in in-vivo xenograft mice models, liver cancer cell-secreted MVs increased the tumor volume even after sorafenib treatment. Further, HGF, also got elevated in liver cancer cell-secreted MVs treatment group and activated Ras protein expression. miR-25 in the cancer cell-secreted MVs was transferred to their host cells HepG2 and Huh7 cells and reversed the sorafenib induced expression of tumor suppressor p53. This in turn induced the expression of FOXM1, a key regulator of cell cycle progression and thus affected the anti-proliferative effect of sorafenib. Therefore, this study reveals that liver cancer cell-derived MVs can mediate sorafenib resistance in the liver cancer cells, suggesting that these MVs may not be utilized as vehicles for anti-cancer drug delivery in liver cancer treatments.


Assuntos
Micropartículas Derivadas de Células/metabolismo , Resistencia a Medicamentos Antineoplásicos/fisiologia , Proteína Forkhead Box M1/biossíntese , Neoplasias Hepáticas/metabolismo , Sorafenibe/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Relação Dose-Resposta a Droga , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica , Células Hep G2 , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Sorafenibe/uso terapêutico , Proteína Supressora de Tumor p53/antagonistas & inibidores , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
7.
Int J Mol Sci ; 22(2)2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33451116

RESUMO

Surgeons rely almost completely on their own vision and palpation to recognize affected tissues during surgery. Consequently, they are often unable to distinguish between different cells and tissue types. This makes accurate and complete resection cumbersome. Targeted image-guided surgery (IGS) provides a solution by enabling real-time tissue recognition. Most current targeting agents (tracers) consist of antibodies or peptides equipped with a radiolabel for Positron Emission Tomography (PET) and Single Photon Emission Computed Tomography (SPECT), magnetic resonance imaging (MRI) labels, or a near-infrared fluorescent (NIRF) dye. These tracers are preoperatively administered to patients, home in on targeted cells or tissues, and are visualized in the operating room via dedicated imaging systems. Instead of using these 'passive' tracers, there are other, more 'active' approaches of probe delivery conceivable by using living cells (macrophages/monocytes, neutrophils, T cells, mesenchymal stromal cells), cell(-derived) fragments (platelets, extracellular vesicles (exosomes)), and microorganisms (bacteria, viruses) or, alternatively, 'humanized' nanoparticles. Compared with current tracers, these active contrast agents might be more efficient for the specific targeting of tumors or other pathological tissues (e.g., atherosclerotic plaques). This review provides an overview of the arsenal of possibilities applicable for the concept of cell-based tracers for IGS.


Assuntos
Rastreamento de Células/métodos , Meios de Contraste , Cirurgia Assistida por Computador/métodos , Micropartículas Derivadas de Células/metabolismo , Humanos , Leucócitos/metabolismo , Imagem por Ressonância Magnética/métodos , Células-Tronco Mesenquimais/metabolismo , Nanopartículas/química , Tomografia por Emissão de Pósitrons/métodos , Cirurgia Assistida por Computador/normas
8.
Int J Mol Sci ; 22(2)2021 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-33466775

RESUMO

The development of malignant effusions such as ascites reflects a massive progression of a malignant disease. In patients with ovarian carcinoma, a high amount of ascites (>500 mL) is an independent negative prognostic marker. The composition and constituents of ascites reflect the inflammatory environment of the underlying tumor. Increased cellular resistance of ascites-derived tumor cells and the development of venous thromboembolic events (VTE) are major risks for these patients, especially in patients with advanced ovarian carcinoma. In this study, we discuss the release of tissue factor-bearing extracellular vesicles (TF+ EVs) from tumor cells into the environment (ascites fluid) and their systemic spreading as a possible causal explanation of the pathologic coagulation status in these patients. We obtained ascites from patients with advanced ovarian carcinoma, collected during surgery or therapeutic paracentesis (n = 20). Larger ectosome-like EVs were isolated using sequential centrifugation, quantified by high-resolution flow cytometry and analyzed using nanoparticle tracking analysis. Furthermore, the pro-coagulant properties (TF activity) of EVs were determined. Compared to published TF activities of EVs from healthy persons, TF activities of EVs derived from ascites of patients with ovarian cancer were very high, with a median of 80 pg/mL. The rate of VTE, as reported in the patient files, was high as well (35%, 7 out of 20). Furthermore, all but one patient with VTE had EV concentrations above the median within their ascetic fluid (p < 0.02). Since VTE continues to be a frequent cause of death in cancer patients, prophylactic antithrombotic treatment might be worth considering in these patients. However, given the risk of bleeding, more clinical data are warranted. Although the study is too small to enable reaching a conclusion on direct clinical implementation, it can well serve as a proof of principle and a rationale to initiate a prospective clinical study with different patient subgroups. We also show ex vivo that these larger ectosome-like EVs induce intracellular ERK phosphorylation and tumor cell migration, which is not directly related to their pro-coagulative potency, but might help to understand why cancer patients with thromboembolic events have a poorer prognosis.


Assuntos
Líquido Ascítico/metabolismo , Micropartículas Derivadas de Células/metabolismo , Vesículas Extracelulares/metabolismo , Neoplasias Ovarianas/metabolismo , Tromboplastina/metabolismo , Idoso , Idoso de 80 Anos ou mais , Ascite/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Feminino , Humanos , Incidência , Pessoa de Meia-Idade , Neoplasias Ovarianas/patologia , Trombose/metabolismo
9.
Methods Mol Biol ; 2258: 273-283, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33340367

RESUMO

The in vitro production of platelets could provide a life-saving intervention for patients that would otherwise require donor-derived platelets. Producing large numbers of platelets in vitro from their progenitor cells, megakaryocytes, remains remarkably difficult and inefficient. Here, a human megakaryoblast leukemia cell line (MEG-01) was used to assess the maturation of megakaryocytes and to develop a new methodology for producing high numbers of platelet-like particles from mature MEG-01 cells in vitro.


Assuntos
Plaquetas/patologia , Micropartículas Derivadas de Células/patologia , Ensaios de Triagem em Larga Escala , Leucemia Megacarioblástica Aguda/patologia , Megacariócitos/patologia , Trombopoese , Plaquetas/metabolismo , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Micropartículas Derivadas de Células/metabolismo , Imunofluorescência , Humanos , Leucemia Megacarioblástica Aguda/metabolismo , Megacariócitos/metabolismo , Microscopia de Fluorescência
11.
Methods Mol Biol ; 2211: 147-170, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33336276

RESUMO

Cell-derived Drug Delivery Systems (DDSs), particularly exosomes, have grown in popularity and have been increasingly explored as novel DDSs, due to their intrinsic targeting capabilities. However, clinical translation of exosomes is impeded by the tedious isolation procedures and poor yield. Cell-derived nanovesicles (CDNs) have recently been produced and proposed as exosome-mimetics. Various methods for producing exosome-mimetics have been developed. In this chapter, we present a simple, efficient, and cost-effective CDNs production method that uses common laboratory equipment (microcentrifuge) and spin cups. Through a series of extrusion and size exclusion steps, CDNs are produced from in vitro cell culture and are found to highly resemble the endogenous exosomes. Thus, we envision that this strategy holds great potential as a viable alternative to exosomes in the development of ideal DDS.


Assuntos
Biomimética , Micropartículas Derivadas de Células , Sistemas de Liberação de Medicamentos , Exossomos , Nanopartículas , Vesículas Transportadoras , Animais , Biomarcadores , Biomimética/métodos , Fracionamento Celular/métodos , Linhagem Celular , Micropartículas Derivadas de Células/metabolismo , Micropartículas Derivadas de Células/ultraestrutura , Células Cultivadas , Fenômenos Químicos , Cromatografia em Gel , Sistemas de Liberação de Medicamentos/métodos , Exossomos/metabolismo , Exossomos/ultraestrutura , Humanos , Camundongos , Nanopartículas/metabolismo , Nanopartículas/ultraestrutura , Preparações Farmacêuticas/administração & dosagem , Preparações Farmacêuticas/química , Vesículas Transportadoras/metabolismo , Vesículas Transportadoras/ultraestrutura
12.
Int J Mol Sci ; 22(1)2020 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-33375718

RESUMO

Red blood cells (RBCs) release extracellular vesicles (EVs) including both endosome-derived exosomes and plasma-membrane-derived microvesicles (MVs). RBC-derived EVs (RBCEVs) are secreted during erythropoiesis, physiological cellular aging, disease conditions, and in response to environmental stressors. RBCEVs are enriched in various bioactive molecules that facilitate cell to cell communication and can act as markers of disease. RBCEVs contribute towards physiological adaptive responses to hypoxia as well as pathophysiological progression of diabetes and genetic non-malignant hematologic disease. Moreover, a considerable number of studies focus on the role of EVs from stored RBCs and have evaluated post transfusion consequences associated with their exposure. Interestingly, RBCEVs are important contributors toward coagulopathy in hematological disorders, thus representing a unique evolving area of study that can provide insights into molecular mechanisms that contribute toward dysregulated hemostasis associated with several disease conditions. Relevant work to this point provides a foundation on which to build further studies focused on unraveling the potential roles of RBCEVs in health and disease. In this review, we provide an analysis and summary of RBCEVs biogenesis, composition, and their biological function with a special emphasis on RBCEV pathophysiological contribution to coagulopathy. Further, we consider potential therapeutic applications of RBCEVs.


Assuntos
Transtornos da Coagulação Sanguínea/etiologia , Transtornos da Coagulação Sanguínea/metabolismo , Eritrócitos/metabolismo , Vesículas Extracelulares/metabolismo , Homeostase , Transporte Biológico , Biomarcadores/metabolismo , Transtornos da Coagulação Sanguínea/terapia , Comunicação Celular , Micropartículas Derivadas de Células/metabolismo , Gerenciamento Clínico , Suscetibilidade a Doenças , Perfilação da Expressão Gênica , Humanos , Óxido Nítrico/metabolismo , Oxirredução
13.
Int J Mol Sci ; 22(1)2020 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-33374978

RESUMO

Exosomes are cell-secreted nanovesicles that naturally contain biomolecular cargoes such as lipids, proteins, and nucleic acids. Exosomes mediate intercellular communication, enabling the transfer biological signals from the donor cells to the recipient cells. Recently, exosomes are emerging as promising drug delivery vehicles due to their strong stability in blood circulation, high biocompatibility, low immunogenicity, and natural targeting ability. In particular, exosomes derived from specific types of cells can carry endogenous signaling molecules with therapeutic potential for cancer treatment, thus presenting a significant impact on targeted drug delivery and therapy. Furthermore, exosomes can be engineered to display targeting moieties on their surface or to load additional therapeutic agents. Therefore, a comprehensive understanding of exosome biogenesis and the development of efficient exosome engineering techniques will provide new avenues to establish convincing clinical therapeutic strategies based on exosomes. This review focuses on the therapeutic applications of exosomes derived from various cells and the exosome engineering technologies that enable the accurate delivery of various types of cargoes to target cells for cancer therapy.


Assuntos
Antineoplásicos/administração & dosagem , Micropartículas Derivadas de Células/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Exossomos/metabolismo , Nanopartículas/metabolismo , Neoplasias/tratamento farmacológico , Animais , Portadores de Fármacos/metabolismo , Humanos , Terapia de Alvo Molecular/métodos
14.
Nat Commun ; 11(1): 4964, 2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-33009394

RESUMO

Thrombosis leads to platelet activation and subsequent degradation; therefore, replenishment of platelets from hematopoietic stem/progenitor cells (HSPCs) is needed to maintain the physiological level of circulating platelets. Platelet-derived microparticles (PMPs) are protein- and RNA-containing vesicles released from activated platelets. We hypothesized that factors carried by PMPs might influence the production of platelets from HSPCs, in a positive feedback fashion. Here we show that, during mouse acute liver injury, the density of megakaryocyte in the bone marrow increases following an increase in circulating PMPs, but without thrombopoietin (TPO) upregulation. In vitro, PMPs are internalized by HSPCs and drive them toward a megakaryocytic fate. Mechanistically, miR-1915-3p, a miRNA highly enriched in PMPs, is transported to target cells and suppresses the expression levels of Rho GTPase family member B, thereby inducing megakaryopoiesis. In addition, direct injection of PMPs into irradiated mice increases the number of megakaryocytes and platelets without affecting TPO levels. In conclusion, our data reveal that PMPs have a role in promoting megakaryocytic differentiation and platelet production.


Assuntos
Plaquetas/metabolismo , Diferenciação Celular , Micropartículas Derivadas de Células/metabolismo , Megacariócitos/citologia , MicroRNAs/metabolismo , Animais , Sequência de Bases , Linhagem Celular , Endocitose , Perfilação da Expressão Gênica , Humanos , Fígado/lesões , Fígado/patologia , Masculino , Megacariócitos/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , MicroRNAs/genética , Poliploidia , Proteína rhoB de Ligação ao GTP/metabolismo
15.
Int J Nanomedicine ; 15: 6409-6420, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32922008

RESUMO

Aim: Tumor cell-derived microparticles (MP) can function as a targeted delivery carrier for anti-tumor drugs. Here, we aimed to generate paclitaxel-loaded microparticles (MP-PTX) from HeLa cells and examined its therapeutic potential on human cervical carcinoma. Methods: MP-PTX was generated from HeLa cells by ultraviolet radiation and subsequent centrifugation. The particle size, drug loading rate, and stability of MP-PTX were examined in vitro. Flow cytometry and the MTT assay were performed to test the inhibitory effect of MP-PTX using different cell lines. Immunodeficient mice bearing HeLa cervical carcinoma were treated with 0.9% normal saline, MP, paclitaxel (PTX) (2.5 mg/kg), or MP-PTX (PTX content identical to PTX group) every day for 6 consecutive days. Tumor volume and animal survival were observed. Micro 18F-FDG PET/CT was performed to monitor the therapeutic efficacy. The proliferation activity of cells and microvessel density in tumor tissues were determined by immunohistochemical staining using Ki-67 and CD31, respectively. Results: Dynamic laser scattering measurements showed that the particle size of MP-PTX was 285.58 ± 2.95 nm and the polydispersity index was 0.104 ± 0.106. And the particle size of MP-PTX was not change at 4°C for at least one week. More than 1% of PTX in the medium could be successfully encapsulated into HeLa cell-derived MP. When compared with PTX, MP-PTX treatment significantly increased apoptosis of tumor cells and reduced their proliferation. In addition, MP-PTX showed lower toxicity to normal human umbilical vein endothelial cells (HUVEC) than PTX. In vivo studies further demonstrated that MP-PTX treatment significantly inhibited the growth of cervical carcinoma, prolonged the survival of tumor-bearing mice, and reduced the toxicity of PTX. Immunohistochemical staining revealed that MP-PTX treatment led to decreased Ki-67 positive tumor cells and decreased microvessel density in tumor tissues. Conclusion: Our results demonstrated that HeLa-derived MP-PTX significantly enhanced the anti-cancer effects of PTX with reduced toxicity, which may provide a novel strategy for the treatment of cervical carcinoma.


Assuntos
Micropartículas Derivadas de Células/metabolismo , Paclitaxel/uso terapêutico , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/patologia , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Micropartículas Derivadas de Células/efeitos dos fármacos , Portadores de Fármacos/química , Células Endoteliais/efeitos dos fármacos , Feminino , Células HeLa , Humanos , Rim/efeitos dos fármacos , Rim/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Nus , Neovascularização Fisiológica/efeitos dos fármacos , Paclitaxel/farmacologia , Tamanho da Partícula
16.
Mem Inst Oswaldo Cruz ; 115: e200082, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32935750

RESUMO

Respiratory failure (RF) is the main cause of hospital admission in HIV/AIDS patients. This study assessed comorbidities and laboratory parameters in HIV/AIDS inpatients with RF (N = 58) in relation to those without RF (N = 36). Tuberculosis showed a huge relative risk and platelet counts were slightly higher in HIV/AIDS inpatients with RF. A flow cytometry assay for reactive oxygen species (ROS) showed lower levels in platelets of these patients in relation to the healthy subjects. However, when stimulated with adrenaline, ROS levels increased in platelets and platelet-derived microparticles of HIV/AIDS inpatients, which may increase the risk of RF during HIV and tuberculosis (HIV-TB) coinfection.


Assuntos
Micropartículas Derivadas de Células/metabolismo , Infecções por HIV/sangue , HIV/imunologia , Espécies Reativas de Oxigênio/sangue , Insuficiência Respiratória/complicações , Fármacos Anti-HIV/uso terapêutico , Biomarcadores/sangue , Plaquetas , Citometria de Fluxo , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Humanos , Insuficiência Respiratória/sangue
17.
Cancer Sci ; 111(9): 3100-3110, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32639675

RESUMO

Mesenchymal stem cells (MSC) are multipotent stromal cells with the potential to differentiate into several cell types. MSC-based therapy has emerged as a promising strategy for various diseases. Accumulating evidence suggests that the paracrine effects of MSC are partially exerted by the secretion of soluble factors, in particular exosomes. MSC-derived exosomes are involved in intercellular communication through transfer of proteins, RNA, DNA and bioactive lipids, which might constitute a novel intercellular communication mode. This review illustrates the current knowledge on the composition and biological functions as well as the therapeutic potential of MSC-derived exosomes in cancer, with a focus on clinical translation opportunities.


Assuntos
Produtos Biológicos/uso terapêutico , Micropartículas Derivadas de Células/metabolismo , Exossomos/metabolismo , Células-Tronco Mesenquimais/metabolismo , Animais , Comunicação Celular , Microambiente Celular , Ensaios Clínicos como Assunto , Sistemas de Liberação de Medicamentos , Humanos , Imunomodulação
18.
Sci Rep ; 10(1): 7871, 2020 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-32398812

RESUMO

Circulating microparticles (MPs) are procoagulant due to the surface containing phosphatidylserine (PS), which facilitates coagulation. We investigated if MPs improve hemostasis in HA plasma models. MPs isolated from pooled normal human plasma were added to severe, moderate and mild HA plasma models (0%, 2.5%, 20% FVIII). The MPs' effect on hemostasis was evaluated by calibrated automated thrombogram (CAT) and overall hemostasis potential (OHP) assays, while fibrin structure was imaged by standard confocal, stimulated emission depletion (STED) microscopy and scanning electron microscopy (SEM). MPs partially restored thrombin generation and fibrin formation in all HA plasma models. The procoagulant effect of MPs requires PS exposure, to a less extent of contact pathway activation, but not tissue factor exposure or in vitro stimulation of MPs. MPs partially normalized the fibrin structure, and using super-resolution STED, MPs attached to fibrin were clearly resolved. In summary, our results demonstrate that PS positive MPs could improve hemostasis in HA plasma models.


Assuntos
Micropartículas Derivadas de Células/metabolismo , Fator VIII/análise , Hemofilia A/sangue , Hemostasia , Fosfatidilserinas/metabolismo , Coagulação Sanguínea , Micropartículas Derivadas de Células/ultraestrutura , Fibrina/metabolismo , Humanos , Microscopia Confocal , Microscopia Eletrônica de Varredura , Trombina/metabolismo , Tromboplastina/metabolismo
19.
PLoS One ; 15(5): e0227932, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32469873

RESUMO

BACKGROUND AND OBJECTIVE: For many pathological states, microparticles are supposed to be one of the causes of hypercoagulation. Although there are some indirect data about microparticles participation in coagulation activation and propagation, the integral hemostasis test Thrombodynamics allows to measure micropaticles participation in these two coagulation phases directly. Demonstrates microparticles participation in coagulation activation by influence on the appearance of coagulation centres in the plasma volume and the rate of clot growth from the surface with immobilized tissue factor.Methods: Microparticles were obtained from platelets and erythrocytes by stimulation with thrombin receptor-activating peptide (SFLLRN) and calcium ionophore (A23187), respectively, from monocytes, endothelial HUVEC culture and monocytic THP cell culture by stimulation with lipopolysaccharides. Microparticles were counted by flow cytometry and titrated in microparticle-depleted normal plasma in the Thrombodynamics test. RESULTS: Monocyte microparticles induced the appearance of clotting centres through the TF pathway at concentrations approximately 100-fold lower than platelet and erythrocyte microparticles, which activated plasma by the contact pathway. For endothelial microparticles, both activation pathways were essential, and their activity was intermediate. Monocyte microparticles induced plasma clotting by the appearance of hundreds of clots with an extremely slow growth rate, while erythrocyte microparticles induced the appearance of a few clots with a growth rate similar to that from surface covered with high-density tissue factor. Patterns of clotting induced by platelet and endothelial microparticles were intermediate. Platelet, erythrocyte and endothelial microparticles impacts on the rate of clot growth from the surface with tissue factor did not differ significantly within the 0-200·103/ul range of microparticles concentrations. However, at concentrations greater than 500·103/ul, erythrocyte microparticles increased the stationary clot growth rate to significantly higher levels than do platelet microparticles or artificial phospholipid vesicles consisting of phosphatidylcholine and phosphatidylserine. CONCLUSION: Microparticles of different origins demonstrated qualitatively different characteristics related to coagulation activation and propagation.


Assuntos
Coagulação Sanguínea/efeitos dos fármacos , Micropartículas Derivadas de Células/efeitos dos fármacos , Trombina/metabolismo , Trombose/sangue , Plaquetas/efeitos dos fármacos , Calcimicina/farmacologia , Cálcio/metabolismo , Micropartículas Derivadas de Células/metabolismo , Células Endoteliais/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Citometria de Fluxo , Células Endoteliais da Veia Umbilical Humana , Humanos , Monócitos/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Trombose/tratamento farmacológico , Trombose/patologia
20.
Mol Cell ; 78(6): 1192-1206.e10, 2020 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-32470318

RESUMO

Tumor-derived extracellular vesicles are important mediators of cell-to-cell communication during tumorigenesis. Here, we demonstrated that hepatocellular carcinoma (HCC)-derived ectosomes remodel the tumor microenvironment to facilitate HCC progression in an ectosomal PKM2-dependent manner. HCC-derived ectosomal PKM2 induced not only metabolic reprogramming in monocytes but also STAT3 phosphorylation in the nucleus to upregulate differentiation-associated transcription factors, leading to monocyte-to-macrophage differentiation and tumor microenvironment remodeling. In HCC cells, sumoylation of PKM2 induced its plasma membrane targeting and subsequent ectosomal excretion via interactions with ARRDC1. The PKM2-ARRDC1 association in HCC was reinforced by macrophage-secreted cytokines/chemokines in a CCL1-CCR8 axis-dependent manner, further facilitating PKM2 excretion from HCC cells to form a feedforward regulatory loop for tumorigenesis. In the clinic, ectosomal PKM2 was clearly detected in the plasma of HCC patients. This study highlights a mechanism by which ectosomal PKM2 remodels the tumor microenvironment and reveals ectosomal PKM2 as a potential diagnostic marker for HCC.


Assuntos
Proteínas de Transporte/metabolismo , Micropartículas Derivadas de Células/metabolismo , Proteínas de Membrana/metabolismo , Hormônios Tireóideos/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Proteínas de Transporte/genética , Diferenciação Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Micropartículas Derivadas de Células/genética , Micropartículas Derivadas de Células/patologia , Quimiocina CCL1/metabolismo , Progressão da Doença , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Macrófagos/metabolismo , Masculino , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Monócitos/metabolismo , Prognóstico , Fator de Transcrição STAT3/metabolismo , Hormônios Tireóideos/genética , Microambiente Tumoral
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