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1.
J Biomed Sci ; 28(1): 3, 2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-33397374

RESUMO

BACKGROUND: Successful pregnancy is supported by a healthy maternal-fetal interface (i.e., the decidual tissues) which holds the conceptus and safeguards it against stressors from the beginning of pregnancy. Any disturbance of this interface can presumably lead to the loss of pregnancy. The use of the immunosuppressive drug mycophenolic acid (MPA) should be discontinued in pregnancy given its abortive and embryotoxic effects. Direct teratogenic effects have been observed in mammalian embryos cultured in MPA, but the underlying mechanisms of abortion by MPA are less understood. METHODS: Decidual stromal cells isolated from human placentas are cultured in the presence of clinically relevant doses of MPA. Data regarding the effects of MPA on the proliferation and viability of decidua cultures are first analysed and then, molecular pathways contributing to these effects are unravelled. RESULTS: MPA treatment of decidual stromal cells results in loss of proliferation capacity and a decrease in the viability of decidua cultures. The molecular pathways involved in the effects of MPA on decidual stromal cells are a reduction in pre-rRNA synthesis and subsequent disruption of the nucleolus. The nucleolar stress stabilizes p53, which in turn, leads to a p21-mediated cell cycle arrest in late S and G2 phases, preventing the progression of the decidua cells into the mitosis. Furthermore, MPA does not induce apoptosis but activate mechanisms of autophagy and senescence in decidual stromal cells. CONCLUSION: The irreversible growth arrest of decidua cells, whose role in the maintenance of the pregnancy microenvironment is known, may be one cause of miscarriage in MPA treated pregnant women.


Assuntos
Aborto Espontâneo/induzido quimicamente , Decídua/fisiopatologia , Imunossupressores/efeitos adversos , Ácido Micofenólico/efeitos adversos , Envelhecimento , Feminino , Humanos , Placenta/fisiopatologia , Gravidez
2.
Molecules ; 25(3)2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32046010

RESUMO

The main strategy of cancer treatment has focused on attacking the tumor cells. Some cancers initially responsive to chemotherapy become treatment-resistant. Another strategy is to block the formation of tumor vessels. However, tumors also become resistant to anti-angiogenic treatments, mostly due to other cells and factors present in the tumor microenvironment, and hypoxia in the central part of the tumor. The need for new cancer therapies is significant. The use of nanoparticle-based therapy will improve therapeutic efficacy and targeting, while reducing toxicity. However, due to inefficient accumulation in tumor sites, clearance by reticuloendothelial organs and toxicity, internalization or conjugation of drug-loaded nanoparticles (NPs) into mesenchymal stem cells (MSCs) can increase efficacy by actively delivering them into the tumor microenvironment. Nanoengineering MSCs with drug-loaded NPs can increase the drug payload delivered to tumor sites due to the migratory and homing abilities of MSCs. However, MSCs have some disadvantages, and exosomes and membranes from different cell types can be used to transport drug-loaded NPs actively to tumors. This review gives an overview of different cancer approaches, with a focus on hypoxia and the emergence of NPs as drug-delivery systems and MSCs as cellular vehicles for targeted delivery due to their tumor-homing potential.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Sistemas de Liberação de Medicamentos/métodos , Nanopartículas/química , Neoplasias/tratamento farmacológico , Neovascularização Patológica/tratamento farmacológico , Animais , Portadores de Fármacos/química , Humanos
3.
Stem Cells Transl Med ; 13(1): 14-29, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38071447

RESUMO

Perinatal derivatives have been proposed as adjunct therapeutic strategies or innovative treatments. Undoubtedly, perinatal derivatives can offer the opportunity and source material to isolate multipotent stem cells, but both maternal- and fetal-derived tissues can be processed and transformed into engineered tissues or advanced biomedical devices, whose potential remains to be fully elucidated. Promising preclinical and clinical results collected so far clearly foresee an escalation of such novel treatments. Market forecasts predict exponential growth in such advanced medicinal products during the next decade, with a pragmatic innovation for medicine into a more advanced biomedical version, enlarging the portfolio for treating a wide range of congenital and acute conditions. However, all these promising and fascinating therapeutic possibilities cannot gain a solid and recognized role in established medical practice without rigid and harmonized manufacturing strategies. The implementation of strategies according to guidelines and directives compiled by Regulatory Agencies, in conformity to (European) Pharmacopoeia and for Good Manufacturing Practice -conforming production of such products, represent critical steps required to translate perinatal technologies into effective therapeutic approaches. During the past 5 years, a panel of European experts and developers, gathered under the umbrella of the COST Sprint Action, supported by the European Cooperation in Science and Technology action, had the opportunity to revise and summarize experience and recommendations for a fruitful and proficient generation of perinatal biomedical products. In order to facilitate the creation and potential commercialization of perinatal bioengineered and advanced pharmaceutical products and technologies, such a collection of data and recommendations is described and discussed here.


Assuntos
Medicina , Engenharia Tecidual , Gravidez , Feminino , Humanos
4.
Cytotherapy ; 14(10): 1182-92, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22900961

RESUMO

BACKGROUND AIMS: Previously, we have shown that human decidua-derived mesenchymal stromal cells (DMSC) are mesenchymal stromal cells (MSC) with a clonal differentiation capacity for the three embryonic layers. The endodermal capacity of DMSC was revealed by differentiation into pulmonary cells. In this study, we examined the hepatic differentiation of DMSC. METHODS: DMSC were cultured in hepatic differentiation media or co-cultured with murine liver homogenate and analyzed with phenotypic, molecular and functional tests. RESULTS AND CONCLUSIONS: DMSC in hepatic differentiation media changed their fibroblast morphology to a hepatocyte-like morphology and later formed a 3-dimensional (3-D) structure or hepatosphere. Moreover, the hepatocyte-like cells and the hepatospheres expressed liver-specific markers such as synthesis of albumin (ALB), hepatocyte growth factor receptor (HGFR), α-fetoprotein (AFP) and cytokeratin-18 (CK-18), and exhibited hepatic functions including glycogen storage capacity and indocyanine green (ICG) uptake/secretion. Human DMSC co-cultured with murine liver tissue homogenate in a non-contact in vitro system showed hepatic differentiation, as evidenced by expression of AFP and ALB genes. The switch in the expression of these two genes resembled liver development. Indeed, the decrease in AFP and increase in ALB expression throughout the co-culture were consistent with the expression pattern observed during normal liver organogenesis in the embryo. Interestingly, AFP and ALB expression was significantly higher when DMSC were co-cultured with injured liver tissue, indicating that DMSC respond differently under normal and pathologic micro-environmental conditions. In conclusion, DMSC-derived hepatospheres and DMSC co-cultured with liver homogenate could be suitable in vitro models for toxicologic, developmental and pre-clinical hepatic regeneration studies.


Assuntos
Diferenciação Celular , Decídua/citologia , Hepatócitos/citologia , Células-Tronco Mesenquimais/citologia , Esferoides Celulares/citologia , Albuminas/genética , Albuminas/metabolismo , Animais , Técnicas de Cocultura , Feminino , Regulação da Expressão Gênica , Glicogênio/metabolismo , Hepatócitos/metabolismo , Humanos , Verde de Indocianina/metabolismo , Fígado/citologia , Camundongos , Camundongos Endogâmicos BALB C , Especificidade de Órgãos , Reação em Cadeia da Polimerase em Tempo Real , Esferoides Celulares/metabolismo
5.
Rev Cient Odontol (Lima) ; 10(3): e125, 2022.
Artigo em Espanhol | MEDLINE | ID: mdl-38389553

RESUMO

Objective: To evaluate the maximum compressive stress in maxillary central incisors restored with fiberglass posts and three types of crowns by the FEM finite element method. Materials and methods: The study was a virtual, descriptive, and laboratory trial. Three virtual models were made using the SolidWorks 2017 software from upper central incisors rehabilitated with fiberglass posts and a metal-ceramic crown, a monolithic lithium disilicate crown, and a zirconium-ceramic crown. They were then subjected to an oblique occlusal load of 150N with an angulation of 45°, distributed towards the palatal aspect. The stress analysis proceeded by comparing the maximum, minimum, and equivalent von Mises stresses. Results: The maximum compressive stress was found at the cervical level in the vestibular area of each of the crowns. Zirconium-ceramic crown (Design 3) was the one with the highest compressive stress with 73.89 MPa, followed by Lithium Disilicate crown (Design 2) with 63.42 MPa and the metal-ceramic crown (Design 1) with 48.4 MPa. Conclusion: The zirconium-ceramic crown better distributes the stress along the tooth since, due to its rigidity, it absorbs the stresses that are concentrated especially in the cervical area, which could indicate that it is the most appropriate option to rehabilitate endodontically treated teeth.

6.
Front Bioeng Biotechnol ; 10: 965006, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35992360

RESUMO

Perinatal derivatives (PnD) are birth-associated tissues, such as placenta, umbilical cord, amniotic and chorionic membrane, and thereof-derived cells as well as secretomes. PnD play an increasing therapeutic role with beneficial effects on the treatment of various diseases. The aim of this review is to elucidate the modes of action of non-hematopoietic PnD on inflammation, angiogenesis and wound healing. We describe the source and type of PnD with a special focus on their effects on inflammation and immune response, on vascular function as well as on cutaneous and oral wound healing, which is a complex process that comprises hemostasis, inflammation, proliferation (including epithelialization, angiogenesis), and remodeling. We further evaluate the different in vitro assays currently used for assessing selected functional and therapeutic PnD properties. This review is a joint effort from the COST SPRINT Action (CA17116) with the intention to promote PnD into the clinics. It is part of a quadrinomial series on functional assays for validation of PnD, spanning biological functions, such as immunomodulation, anti-microbial/anti-cancer activities, anti-inflammation, wound healing, angiogenesis, and regeneration.

7.
Front Cell Dev Biol ; 10: 1033080, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36742196

RESUMO

Stress urinary incontinence (SUI) is a condition that causes the involuntary loss of urine when making small efforts, which seriously affects daily life of people who suffer from it. Women are more affected by this form of incontinence than men, since parity is the main risk factor. Weakening of the pelvic floor tissues is the cause of SUI, although a complete understanding of the cellular and molecular mechanisms of the pathology is still lacking. Reconstructive surgery to strengthen tissue in SUI patients is often associated with complications and/or is ineffective. Mesenchymal stromal cells from the maternal side of the placenta, i.e. the decidua, are proposed here as a therapeutic alternative based on the regenerative potential of mesenchymal cells. The animal model of SUI due to vaginal distention simulating labor has been used, and decidual mesenchymal stromal cell (DMSC) transplantation was effective in preventing a drop in pressure at the leak point in treated animals. Histological analysis of the urethras from DMSC-treated animals after VD showed recovery of the muscle fiber integrity, low or no extracellular matrix (ECM) infiltration and larger elastic fibers near the external urethral sphincter, compared to control animals. Cells isolated from the suburethral connective tissue of SUI patients were characterized as myofibroblasts, based on the expression of several specific genes and proteins, and were shown to achieve premature replicative senescence. Co-culture of SUI myofibroblasts with DMSC via transwell revealed a paracrine interaction between the cells through signals that mediated DMSC migration, SUI myofibroblast proliferation, and modulation of the proinflammatory and ECM-degrading milieu that is characteristic of senescence. In conclusion, DMSC could be an alternative therapeutic option for SUI by counteracting the effects of senescence in damaged pelvic tissue.

8.
Pharmaceutics ; 13(12)2021 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-34959429

RESUMO

Allergy constitutes a major health issue due to its large prevalence. The established therapeutic approaches (allergen avoidance, antihistamines, and corticosteroids) do not address the underlying causes of the pathology, highlighting the need for other long-term treatment options. Antigen-specific immunotherapy enables the long-term control of allergic diseases by promoting immunological tolerance to the allergen. However, efficacious immunotherapies are not available for all possible allergens, and the risk of undesired reactions during therapy remains a concern, especially in patients with severe allergic reactions. In this context, two types of therapeutic strategies appear especially promising for the future in the context of allergy: cell therapy and bio- or nano-material-based therapy. In this review, the main strategies developed this far in these two types of strategies are discussed, with several examples illustrating the different approaches.

9.
Biomed Pharmacother ; 142: 112059, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34467894

RESUMO

Deficiency of factor V is a congenital autosomal recessive coagulopathy associated with mutations in the F5 gene that results in mild-to-severe bleeding episodes. Factor V is a component of the prothrombinase complex responsible for accelerating conversion of prothrombin to thrombin. At the present time there are no therapeutic factor V concentrates available. This study was designed to lay the preliminary foundations for future cell-based therapy for patients with severe factor V deficiency. The study showed that hepatospheres, which produce coagulation factors VIII, IX, and V, synthetize and store intracellular glycogen and express albumin levels up to 8 times higher than those of undifferentiated cells. Factor IX and factor V gene expression increased significantly in hepatospheres as compared to undifferentiated cells, whereas factor VIII gene expression remained constant. The factor V protein was detected in the hepatospheres´ secretome. Considering the enormous potential of mesenchymal stem cells as therapeutic agents, this study proposes a highly reproducible method to induce differentiation of mesenchymal stem cells from human placenta to factor V-producing hepatospheres. This strategy constitutes a preliminary step towards a curative treatment of factor V deficiency through advanced therapies such as cell therapy.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos/métodos , Decídua/citologia , Deficiência do Fator V/terapia , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Albuminas/genética , Albuminas/metabolismo , Técnicas de Cultura de Células , Diferenciação Celular , Fator IX/genética , Fator IX/metabolismo , Fator V/genética , Fator V/metabolismo , Fator VIII/genética , Fator VIII/metabolismo , Feminino , Hepatócitos/citologia , Hepatócitos/metabolismo , Humanos , Secretoma/metabolismo , Esferoides Celulares/citologia , Esferoides Celulares/metabolismo
10.
Pharmaceutics ; 13(2)2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33578733

RESUMO

Combination therapies constitute a powerful tool for cancer treatment. By combining drugs with different mechanisms of action, the limitations of each individual agent can be overcome, while increasing therapeutic benefit. Here, we propose employing tumor-migrating decidua-derived mesenchymal stromal cells as therapeutic agents combining antiangiogenic therapy and chemotherapy. First, a plasmid encoding the antiangiogenic protein endostatin was transfected into these cells by nucleofection, confirming its expression by ELISA and its biological effect in an ex ovo chick embryo model. Second, doxorubicin-loaded mesoporous silica nanoparticles were introduced into the cells, which would act as vehicles for the drug being released. The effect of the drug was evaluated in a coculture in vitro model with mammary cancer cells. Third, the combination of endostatin transfection and doxorubicin-nanoparticle loading was carried out with the decidua mesenchymal stromal cells. This final cell platform was shown to retain its tumor-migration capacity in vitro, and the combined in vitro therapeutic efficacy was confirmed through a 3D spheroid coculture model using both cancer and endothelial cells. The results presented here show great potential for the development of combination therapies based on genetically-engineered cells that can simultaneously act as cellular vehicles for drug-loaded nanoparticles.

11.
J Neurosci ; 29(21): 6860-70, 2009 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-19474313

RESUMO

Mammalian target of rapamycin (mTOR), a well known Akt substrate, regulates multiple cellular functions including cell growth and protein synthesis. The current study identifies a novel role of the Akt/mTOR pathway as a regulator of CNS myelination. Previously, we showed that overexpressing constitutively active Akt in oligodendrocytes in a transgenic mouse model induces enhanced CNS myelination, with no changes in the proliferation or survival of oligodendrocyte progenitor or mature cells. The present study focused on the signaling mechanisms regulating this hypermyelination induced by Akt. Activation of mTOR and its downstream substrates (p70S6 kinase and S6 ribosomal protein) was observed in Akt-overexpressing oligodendrocytes. When mTOR signaling was inhibited chronically in vivo with rapamycin starting at 6 weeks of age, the observed hypermyelination was reduced to approximately the amount of myelin seen in wild-type mice. mTOR inhibition had little impact on wild-type myelination between 6 and 12 weeks of age, suggesting that, in normal adults, myelination is relatively complete and is no longer regulated by mTOR signaling. However, when mTOR was chronically inhibited in young adult wild-type mice, myelination was reduced. These results suggest that, during active myelination, the major Akt signal regulating CNS myelination is the mTOR pathway.


Assuntos
Sistema Nervoso Central/metabolismo , Proteínas da Mielina/metabolismo , Proteína Oncogênica v-akt/metabolismo , Proteínas Quinases/metabolismo , Transdução de Sinais/fisiologia , 2',3'-Nucleotídeo Cíclico Fosfodiesterases/metabolismo , Animais , Animais Recém-Nascidos , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Sistema Nervoso Central/efeitos dos fármacos , Sistema Nervoso Central/ultraestrutura , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/fisiologia , Imunossupressores/farmacologia , Camundongos , Camundongos Transgênicos , Microscopia Eletrônica de Transmissão/métodos , Proteínas da Mielina/genética , Proteína Proteolipídica de Mielina/genética , Bainha de Mielina/efeitos dos fármacos , Bainha de Mielina/metabolismo , Fibras Nervosas Mielinizadas/efeitos dos fármacos , Fibras Nervosas Mielinizadas/metabolismo , Fibras Nervosas Mielinizadas/ultraestrutura , Proteínas do Tecido Nervoso/metabolismo , Fator de Transcrição 2 de Oligodendrócitos , Oligodendroglia/efeitos dos fármacos , Oligodendroglia/metabolismo , Proteína Oncogênica v-akt/genética , Transdução de Sinais/efeitos dos fármacos , Sirolimo/farmacologia , Serina-Treonina Quinases TOR , Fatores de Tempo
12.
Am J Obstet Gynecol ; 203(5): 495.e9-495.e23, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20692642

RESUMO

OBJECTIVE: The objective of the study was to isolate and characterize a population of mesenchymal stem cells (MSCs) from human term placental membranes. STUDY DESIGN: We isolated an adherent cell population from extraembryonic membranes. Morphology, phenotype, growth characteristics, karyotype, and immunological and differentiation properties were analyzed. RESULTS: The isolated placental MSCs were from maternal origin and named as decidua-derived mesenchymal stem cells (DMSCs). DMSCs differentiated into derivatives of all germ layers. It is the first report about placental MSC differentiation into alveolar type II cells. Clonally expanded DMSCs differentiated into all embryonic layers, including pulmonary cells. DMSCs showed higher life span than placental cells from fetal origin and proliferated without genomic instability. CONCLUSION: The data suggest that DMSCs are true multipotent MSCs, distinguishing them from other placental MSCs. DMSCs could be safely used in the mother as a potential source of MSCs for pelvic floor dysfunctions and immunological diseases. Additionally, frozen DMSCs can be stored for both autologous and allogeneic tissue regeneration.


Assuntos
Diferenciação Celular , Linhagem da Célula , Decídua/citologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Multipotentes/citologia , Adulto , Antígenos CD/metabolismo , Células Cultivadas , Decídua/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Imunofenotipagem , Hibridização in Situ Fluorescente , Cariotipagem , Células-Tronco Mesenquimais/metabolismo , Repetições de Microssatélites , Células-Tronco Multipotentes/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Telomerase/metabolismo
13.
Genes (Basel) ; 12(1)2020 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-33374593

RESUMO

The placenta is a temporary organ that is discarded after birth and is one of the most promising sources of various cells and tissues for use in regenerative medicine and tissue engineering, both in experimental and clinical settings. The placenta has unique, intrinsic features because it plays many roles during gestation: it is formed by cells from two individuals (mother and fetus), contributes to the development and growth of an allogeneic fetus, and has two independent and interacting circulatory systems. Different stem and progenitor cell types can be isolated from the different perinatal tissues making them particularly interesting candidates for use in cell therapy and regenerative medicine. The primary source of perinatal stem cells is cord blood. Cord blood has been a well-known source of hematopoietic stem/progenitor cells since 1974. Biobanked cord blood has been used to treat different hematological and immunological disorders for over 30 years. Other perinatal tissues that are routinely discarded as medical waste contain non-hematopoietic cells with potential therapeutic value. Indeed, in advanced perinatal cell therapy trials, mesenchymal stromal cells are the most commonly used. Here, we review one by one the different perinatal tissues and the different perinatal stem cells isolated with their phenotypical characteristics and the preclinical uses of these cells in numerous pathologies. An overview of clinical applications of perinatal derived cells is also described with special emphasis on the clinical trials being carried out to treat COVID19 pneumonia. Furthermore, we describe the use of new technologies in the field of perinatal stem cells and the future directions and challenges of this fascinating and rapidly progressing field of perinatal cells and regenerative medicine.


Assuntos
COVID-19/terapia , Placenta/citologia , SARS-CoV-2 , Transplante de Células-Tronco/tendências , Células-Tronco/citologia , Líquido Amniótico/citologia , Ensaios Clínicos como Assunto , Transplante de Células-Tronco de Sangue do Cordão Umbilical/métodos , Transplante de Células-Tronco de Sangue do Cordão Umbilical/tendências , Síndrome da Liberação de Citocina/terapia , Portadores de Fármacos , Membranas Extraembrionárias/citologia , Feminino , Previsões , Células-Tronco Hematopoéticas/citologia , Humanos , Pulmão/patologia , Ativação de Macrófagos , Células-Tronco Mesenquimais/citologia , Nanopartículas , Gravidez , Preservação Biológica , Medicina Regenerativa/métodos , Transplante de Células-Tronco/métodos , Células-Tronco/imunologia
14.
Sci Rep ; 10(1): 3910, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-32127622

RESUMO

An emerging disturbance for Caribbean reefs is the massive arrival of pelagic Sargassum, which deteriorates water quality due to the production of leachates. The highest arrivals of Sargassum took place when broadcasting corals spawned. We experimentally determined the effect of Sargassum leachates on swimming behavior of Acropora palmata larvae through five treatments (control, stain (simulating 100% leachate color), and 25%, 50% and 100% Sargassum leachate concentrations) during 30 min (10 min of videos and 20 min of post-observations). In the videos, larvae with leachates reduced swimming speed, were positively geotactic, the percentage of individuals that swam in a spiral pattern increased, and most behavioral displacements occurred at lower frequencies than larvae without leachates. Moreover, symptomatic spiral behavior was higher in the presence of leachates, suggesting that this behavior may be an effect of pollution. During post-observations, most larvae with leachates were motionless. This is the first time that Sargassum leachates have been documented modifying larval swimming behavior, which may reduce larval dispersion and genetic diversity. We suggest that a future evaluation of the effects of leachates at lower concentrations and over longer periods of exposure is needed. The resilience of corals may be compromised if Sargassum arrivals become frequent events.


Assuntos
Antozoários/efeitos dos fármacos , Antozoários/fisiologia , Larva/efeitos dos fármacos , Larva/fisiologia , Sargassum/metabolismo , Natação , Animais , Reprodução/efeitos dos fármacos
15.
J Neurosci ; 28(28): 7174-83, 2008 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-18614687

RESUMO

The serine/threonine kinase Akt regulates multiple cellular functions. The current studies identify a new role for Akt in CNS myelination. In earlier studies on cultured oligodendrocytes, we showed that neuregulin signals through phosphatidylinositol-3'-OH kinase and Akt to enhance survival of oligodendrocytes. However, when transgenic animals were generated that overexpressed constitutively active Akt in oligodendrocytes and their progenitor cells, no enhanced survival of oligodendrocytes or progenitors was found. No alteration in the proliferation or death of progenitors was noted. In contrast, the major impact of Akt overexpression in oligodendrocytes was enhanced myelination. Most interestingly, oligodendrocytes in these mice continued actively myelinating throughout life. Thus, expression of constitutively active Akt in oligodendrocytes and their progenitor cells generated no more oligodendrocytes, but dramatically more myelin. The increased myelination continued as these mice aged, resulting in enlarged optic nerves and white matter areas. In older animals with enlarged white matter areas, the density of oligodendrocytes was reduced, but because of the increased area, the total number of oligodendrocytes remained comparable with wild-type controls. Interestingly, in these animals, overexpression of Akt in Schwann cells did not impact myelination. Thus, in vivo, constitutively active Akt enhances CNS myelination but not PNS myelination and has no impact developmentally on oligodendrocyte number. Understanding the unique aspects of Akt signal transduction in oligodendrocytes that lead to myelination rather than uncontrolled proliferation of oligodendrocyte progenitor cells may have important implications for understanding remyelination in the adult nervous system.


Assuntos
Sistema Nervoso Central/fisiologia , Regulação da Expressão Gênica/fisiologia , Bainha de Mielina/fisiologia , Proteína Oncogênica v-akt/fisiologia , Fatores Etários , Animais , Bromodesoxiuridina/metabolismo , Morte Celular/fisiologia , Proliferação de Células , Sistema Nervoso Central/citologia , Proteínas de Fluorescência Verde/biossíntese , Camundongos , Camundongos Transgênicos , Microscopia Eletrônica de Transmissão/métodos , Proteína Proteolipídica de Mielina/genética , Bainha de Mielina/ultraestrutura , Oligodendroglia/fisiologia , Oligodendroglia/ultraestrutura , Proteína Oncogênica v-akt/genética , Nervo Óptico/fisiologia , Nervo Óptico/ultraestrutura , Nervo Isquiático/fisiologia , Nervo Isquiático/ultraestrutura , Serina/metabolismo , Treonina/metabolismo
16.
Transfusion ; 49(4): 636-47, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19055702

RESUMO

BACKGROUND: The CD34+ cell content is a predictive factor for engraftment and survival after umbilical cord blood (UCB) transplantation. The high variability in the CD34 assay results in different recommended cell doses for infusion across transplant centers and also limits the clinical utility of the CD34+ cell counts provided by cord blood banks (CBBs). This bi-institutional study was intended to understand the sources of this variability. STUDY DESIGN AND METHODS: The level of CD34 agreement between the University of Minnesota (UM) and the Madrid CBB (MCBB) was evaluated on 50 UCB units before and after cryopreservation. Two cryopreserved vials per unit were thawed and processed at both laboratories. Dual-platform ISHAGE-based flow cytometry was used for CD34 enumeration. RESULTS: Postthaw nucleated cell recoveries were similar. However, whereas CD34+ cell enumeration before freezing was 0.35 +/- 0.22 percent, the results after thawing were 0.98 +/- 0.65 and 0.57 +/- 0.39 percent at UM and MCBB, respectively. Bland-Altman plots analysis ruled out the interchangeability of MCBB and UM CD34 values. Differences in the initial cell acquisition settings accounted for most of the CD34 discrepancy, which was no longer present after normalization of the forward scatter threshold for cell acquisition. CONCLUSIONS: The standardization of CD34+ cell enumeration by flow cytometry is strongly reliant on a consistent initial cell acquisition procedure. The interlaboratory variation can be minimized by using frozen cell aliquots as reference samples. Both requisites should be considered for CD34 testing and UCB unit selection by regulatory institutions involved with cord blood banking and transplantation.


Assuntos
Antígenos CD34/metabolismo , Criopreservação , Fator VIII/análise , Sangue Fetal/citologia , Fibrinogênio/análise , Citometria de Fluxo/normas , Antígenos CD34/análise , Antígenos CD34/sangue , Contagem de Células Sanguíneas/métodos , Contagem de Células Sanguíneas/normas , Separação Celular/métodos , Separação Celular/normas , Sobrevivência Celular , Células Cultivadas , Transplante de Células-Tronco de Sangue do Cordão Umbilical/métodos , Transplante de Células-Tronco de Sangue do Cordão Umbilical/normas , Criopreservação/métodos , Fator VIII/metabolismo , Sangue Fetal/metabolismo , Fibrinogênio/metabolismo , Citometria de Fluxo/métodos , Humanos , Modelos Lineares , Análise por Pareamento , Reprodutibilidade dos Testes
17.
Indian Heart J ; 61(5): 422-32, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20635756

RESUMO

Management of acute myocardial infarction (AMI) has undergone seismic changes in the last two decades, primarily with the global availability of thrombolytic agents and with the burgeoning use of Primary PCI. Application of these two modalities has dramatically reduced both the mortality and morbidity from AMI. Advances in thrombolytic therapy have been noteworthy in three areas: firstly, in genetically engineering superior third-generation lytic agents: secondly, in developing protocols of appropriate use, and thirdly, creating unambiguous guidelines for admninistration of thrombolytics, of utilizing Primary PCI, or hybrid strategies. Our submitted review on thrombolytic therapy builds on this scientific progress. It provides a pertinent historical perspective that elucidates discovery of lytic agents and the vast array of biogenetic inventions that lead to the development of the novel agent, tenecteplase. The review manuscript also provides a comprehensive compendium of the numerous clinical trials that have been methodically presented in easy-to-read tables. We have additionally designed these tables to facilitate comparison of different lytic agents and for critical analysis of the individual clinical trials. Finally, to make this review most relevant for the IHJ, a section has been devoted to the use of thrombolytic therapy in India. Unique attributes of tenecteplase have been discussed and the benefits of using it to treat Indian patients have been highlighted.


Assuntos
Fibrinolíticos/uso terapêutico , Infarto do Miocárdio/tratamento farmacológico , Ativador de Plasminogênio Tecidual/uso terapêutico , Angioplastia Coronária com Balão , Fibrinolíticos/administração & dosagem , Heparina de Baixo Peso Molecular/uso terapêutico , Humanos , Infarto do Miocárdio/terapia , Ensaios Clínicos Controlados Aleatórios como Assunto , Tenecteplase , Ativador de Plasminogênio Tecidual/administração & dosagem , Resultado do Tratamento
18.
Acta Biomater ; 83: 372-378, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30414488

RESUMO

A Trojan-horse strategy for cancer therapy employing tumor-tropic mesenchymal stem cells transfected with a non-viral nanovector is here presented. In this sense, ultrasound-responsive mesoporous silica nanoparticles were coated with a polycation (using two different molecular weights), providing them with gene transfection capabilities that were evaluated using two different plasmids. First, the expression of Green Fluorescent Protein was analyzed in Decidua-derived Mesenchymal Stem Cells after incubation with the silica nanoparticles. The most successful nanoparticle was then employed to induce the expression of two suicide genes: cytosine deaminase and uracil phosphoribosyl transferase, which allow the cells to convert a non-toxic pro-drug (5-fluorocytosine) into a toxic drug (5-Fluorouridine monophosphate). The effect of the production of the toxic final product was also evaluated in a cancer cell line (NMU cells) co-cultured with the transfected vehicle cells, Decidua-derived Mesenchymal Stem Cells. STATEMENT OF SIGNIFICANCE: Cell-mediated cancer therapy has recently attracted great interest. Tumor-homing cells can exert anticancer effects through innate capacities, via transfection with a therapeutic gene or acting as vehicles of therapeutic nanoparticles. In this work, an ultrasound-responsive mesoporous silica nanoparticle (capable of carrying an anticancer drug) is engineered to act as a non-viral transfection agent for tumor-tropic human placental mesenchymal stem cells. The successful transfection of the vehicle cells is evaluated employing different expression plasmids. After transfection with two suicide genes, the vehicle cells are capable of converting a non-toxic pro-drug into a highly toxic molecule, which can also kill surrounding cancer cells in an in vitro co-culture model. This work opens the gate for a plethora of strategies in which both genes and drug-loaded nanoparticles can be transported towards tumor tissues by easily available human mesenchymal stem cells.


Assuntos
Decídua/metabolismo , Genes Transgênicos Suicidas , Células-Tronco Mesenquimais/metabolismo , Nanopartículas/química , Dióxido de Silício/química , Transfecção , Ondas Ultrassônicas , Decídua/citologia , Feminino , Terapia Genética , Humanos , Células-Tronco Mesenquimais/citologia , Gravidez
19.
Thromb Haemost ; 118(8): 1370-1381, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29991091

RESUMO

The development of new strategies based on cell therapy approaches to correct haemophilia A (HA) requires further insights into new cell populations capable of producing coagulation factor VIII (FVIII) and presenting stable engraftment potential. The major producers of FVIII in the adult are liver sinusoidal endothelial cells (LSECs) and in a lesser degree bone marrow-derived cells, both of which have been shown to ameliorate the bleeding phenotype in adult HA mice after transplantation. We have previously shown that cells from the foetal liver (FL) and the aorta-gonads-mesonephros (AGM) haematopoietic locations possess higher LSEC engraftment potential in newborn mice compared with adult-derived LSECs, constituting likely therapeutic targets for the treatment of HA in neonates. However, less is known about the production of FVIII in embryonic locations. Quantitative polymerase chain reaction and Western blot analysis were performed to assess the relative level of FVIII production in different embryonic tissues and at various developmental stages, identifying the FL and AGM region from day 12 (E12) as prominent sources of FVIII. Furthermore, FL-derived VE-cad+CD45-Lyve1+/- endothelial/endothelial progenitor cells, presenting vascular engraftment potential, produced high levels of F8 ribonucleic acid compared with CD45+ blood progenitors or Dlk1+ hepatoblasts. In addition, we show that the E11 AGM explant cultures expanded cells with LSEC repopulation activity, instrumental to further understand signals for in vitro generation of LSECs. Taking into account the capacity for FVIII expression, culture expansion and newborn engraftment potential, these results support the use of cells with foetal characteristics for correction of FVIII deficiency in young individuals.


Assuntos
Aorta/metabolismo , Células Progenitoras Endoteliais/metabolismo , Fator VIII/metabolismo , Gônadas/metabolismo , Hemofilia A/metabolismo , Fígado/metabolismo , Mesonefro/metabolismo , Animais , Aorta/embriologia , Aorta/transplante , Diferenciação Celular , Células Progenitoras Endoteliais/transplante , Fator VIII/genética , Regulação da Expressão Gênica no Desenvolvimento , Idade Gestacional , Gônadas/embriologia , Gônadas/transplante , Hemofilia A/genética , Hemofilia A/cirurgia , Fígado/embriologia , Mesonefro/embriologia , Mesonefro/transplante , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Camundongos Transgênicos , Fenótipo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transplante de Células-Tronco/métodos , Técnicas de Cultura de Tecidos
20.
Nanoscale ; 9(17): 5528-5537, 2017 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-28402365

RESUMO

A new platform constituted by engineered responsive nanoparticles transported by human mesenchymal stem cells is here presented as a proof of concept. Ultrasound-responsive mesoporous silica nanoparticles are coated with polyethylenimine to favor their effective uptake by decidua-derived mesenchymal stem cells. The responsive-release ability of the designed nanoparticles is confirmed, both in vial and in vivo. In addition, this capability is maintained inside the cells used as carriers. The migration capacity of the nanoparticle-cell platform towards mammary tumors is assessed in vitro. The efficacy of this platform for anticancer therapy is shown against mammary tumor cells by inducing the release of doxorubicin only when the cell vehicles are exposed to ultrasound.


Assuntos
Decídua/citologia , Portadores de Fármacos , Neoplasias Mamárias Experimentais/tratamento farmacológico , Células-Tronco Mesenquimais/efeitos dos fármacos , Nanopartículas , Animais , Células Cultivadas , Doxorrubicina/administração & dosagem , Feminino , Humanos , Camundongos , Porosidade , Ratos Sprague-Dawley , Dióxido de Silício , Ondas Ultrassônicas
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