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Endothelial progenitor cells (EPCs) are stem cells mainly derived from bone marrow; from where they migrate to repair and regenerate damaged tissues. eEPCs have been classified into two sub-populations, early (eEPC) and late EPCs (lEPC), depending on maturation stages in vitro. In addition, eEPC release endocrine mediators, including small extracellular vesicles (sEVs), which in turn may enhance the eEPC-mediated wound healing properties. Nevertheless, adenosine contributes to angiogenesis by recruiting eEPC at the injury site. However, whether ARs may enhance the secretome of eEPC, including sEVs, is unknown. Therefore, we aimed to investigate whether AR activation increase the release of sEVs in eEPC, which in turn has paracrine effects on recipient endothelial cells. Results shown that 5'-N-ethylcarboxamidoadenosine (NECA), a non-selective agonist, increase both the protein levels of the vascular endothelial growth factor (VEGF), and the number of sEVs released to the conditioned medium (CM) in primary culture of eEPC. Importantly, CM and EVs harvested from NECA-stimulated eEPC promote in vitro angiogenesis, without changes in cell proliferation, in recipient ECV-304 endothelial cells. This constitutes the first evidence showing that adenosine enhances sEVs release from eEPC, which has pro-angiogenic capacity on recipient endothelial cells.
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Células Progenitoras Endoteliais , Humanos , Células Progenitoras Endoteliais/metabolismo , Adenosina/farmacologia , Adenosina/metabolismo , Adenosina-5'-(N-etilcarboxamida)/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Células-Tronco/metabolismo , Meios de Cultivo Condicionados/metabolismoRESUMO
Chitosan (CS)-based scaffolds loaded with Pinus radiata extract bark (PE) and grape seed extract (GSE) were successfully developed for wound dressing applications. The effects of incorporating GSE and PE in CS scaffolds were investigated in relation to their physicochemical and biological properties. All scaffolds exhibited porous structures with the ability to absorb more than 70 times their weight when contacted with blood and phosphate buffer solution. The incorporation of GSE and PE into the CS scaffolds increased their blood absorption ability and degradation rates over time. All scaffolds showed a clotting ability above 95%, with their surfaces being favorable for red blood cell attachment. Both GSE and PE were released from the CS scaffolds in a sustained manner. Scaffolds loaded with GSE and PE inhibited the bacterial activity of S. aureus and E. coli by 40% and 44% after 24 h testing. In vitro cell viability studies demonstrated that all scaffolds were nontoxic to HaCaT cells. Importantly, the addition of GSE and PE further increased cell viability compared to that of the CS scaffold. This study provides a new synthesis method to immobilize GSE and PE on CS scaffolds, enabling the formation of novel material platforms with a high potential for wound dressing applications.
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Quitosana , Quitosana/química , Staphylococcus aureus , Escherichia coli , Alicerces Teciduais/química , Bandagens , Antibacterianos/farmacologia , Antibacterianos/químicaRESUMO
Tissue regeneration is often impaired in patients with metabolic disorders such as diabetes mellitus and obesity, exhibiting reduced wound repair and limited regeneration capacity. We and others have demonstrated that wound healing under normal metabolic conditions is potentiated by the secretome of human endothelial cell-differentiated mesenchymal stem cells (hMSC-EC). However, it is unknown whether this effect is sustained under hyperglycemic conditions. In this study, the wound healing effect of secretomes from undifferentiated human mesenchymal stem cells (hMSC) and hMSC-EC in a type-2 diabetes mouse model was analyzed. hMSC were isolated from human Wharton's jelly and differentiated into hMSC-EC. hMSC and hMSC-EC secretomes were analyzed and their wound healing capacity in C57Bl/6J mice fed with control (CD) or high fat diet (HFD) was evaluated. Our results showed that hMSC-EC secretome enhanced endothelial cell proliferation and wound healing in vivo when compared with hMSC secretome. Five soluble proteins (angiopoietin-1, angiopoietin-2, Factor de crecimiento fibroblástico, Matrix metallopeptidase 9, and Vascular Endothelial Growth Factor) were enriched in hMSC-EC secretome in comparison to hMSC secretome. Thus, the five recombinant proteins were mixed, and their pro-healing property was evaluated in vitro and in vivo. Functional analysis demonstrated that a cocktail of these proteins enhanced the wound healing process similar to hMSC-EC secretome in HFD mice. Overall, our results show that hMSC-EC secretome or a combination of specific proteins enriched in the hMSC-EC secretome enhanced wound healing process under hyperglycemic conditions.
Assuntos
Meios de Cultivo Condicionados/farmacologia , Diabetes Mellitus Tipo 2/metabolismo , Células-Tronco Mesenquimais/citologia , Proteínas Recombinantes/farmacologia , Cicatrização/efeitos dos fármacos , Angiopoietina-1/metabolismo , Angiopoietina-1/farmacologia , Angiopoietina-2/metabolismo , Angiopoietina-2/farmacologia , Animais , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Meios de Cultivo Condicionados/química , Diabetes Mellitus Tipo 2/induzido quimicamente , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Humanos , Metaloproteinase 9 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/farmacologia , Células-Tronco Mesenquimais/metabolismo , Camundongos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fator A de Crescimento do Endotélio Vascular/farmacologia , Geleia de Wharton/citologia , Geleia de Wharton/metabolismoRESUMO
Oxidized low-density lipoprotein (ox-LDL) is the most harmful form of cholesterol associated with vascular atherosclerosis and hepatic injury, mainly due to inflammatory cell infiltration and subsequent severe tissue injury. Lox-1 is the central ox-LDL receptor expressed in endothelial and immune cells, its activation regulating inflammatory cytokines and chemotactic factor secretion. Recently, a Lox-1 truncated protein isoform lacking the ox-LDL binding domain named LOXIN has been described. We have previously shown that LOXIN overexpression blocked Lox-1-mediated ox-LDL internalization in human endothelial progenitor cells in vitro. However, the functional role of LOXIN in targeting inflammation or tissue injury in vivo remains unknown. In this study, we investigate whether LOXIN modulated the expression of Lox-1 and reduced the inflammatory response in a high-fat-diet mice model. Results indicate that human LOXIN blocks Lox-1 mediated uptake of ox-LDL in H4-II-E-C3 cells. Furthermore, in vivo experiments showed that overexpression of LOXIN reduced both fatty streak lesions in the aorta and inflammation and fibrosis in the liver. These findings were associated with the down-regulation of Lox-1 in endothelial cells. Then, LOXIN prevents hepatic and aortic tissue damage in vivo associated with reduced Lox-1 expression in endothelial cells. We encourage future research to understand better the underlying molecular mechanisms and potential therapeutic use of LOXIN.
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Aterosclerose , Células Progenitoras Endoteliais , Ftalazinas , Animais , Aorta/metabolismo , Aorta/patologia , Aterosclerose/tratamento farmacológico , Aterosclerose/etiologia , Aterosclerose/metabolismo , Aterosclerose/patologia , Células Cultivadas , Dieta Hiperlipídica/efeitos adversos , Células Progenitoras Endoteliais/efeitos dos fármacos , Células Progenitoras Endoteliais/metabolismo , Células Progenitoras Endoteliais/patologia , Inflamação/tratamento farmacológico , Inflamação/genética , Inflamação/metabolismo , Inflamação/patologia , Lipoproteínas LDL/metabolismo , Fígado/metabolismo , Camundongos , Ftalazinas/farmacologia , Receptores Depuradores Classe E/genética , Receptores Depuradores Classe E/metabolismoRESUMO
We aim to investigate the role of A2A receptor in peritonitis-related sepsis by injection of a fecal solution (FS) as a model of polymicrobial infection. C57/black J6 wild-type (WT) and A2A-deficient mice (A2AKO) were exposed to sepsis induced by intraperitoneal injection of a FS (FS-induced peritonitis) or instead was injected with saline buffer (Sham). Survival rate and sepsis score were measured up to 48 h. The presence of bacteria in tissue homogenates was analyzed. Telemetry and speckle laser Doppler were used for systemic blood pressure and peripheral blood perfusion analysis, respectively. Histological analysis and identification of active caspase 3 were performed in selected organs, including the liver. The survival rate of A2AKO mice exposed to FS-induced peritonitis was significantly higher, and the sepsis score was lower than their respective WT counterpart. Injection of FS increases (50 to 150 folds) the number of colonies forming units in the liver, kidney, blood, and lung in WT mice, while these effects were significantly attenuated in A2AKO mice exposed to FS-induced peritonitis. A significant reduction in both systolic and diastolic blood pressure, as well as in the peripheral perfusion was observed in WT and A2AKO mice exposed to FS-induced peritonitis. Although, these last effects were significantly attenuated in A2AKO mice. Histological analysis showed a large perivascular infiltration of polymorphonuclear in the liver of WT and A2AKO mice exposed to FS-induced peritonitis, but again, this effect was attenuated in A2AKO mice. Finally, high expression of active caspase 3 was found only in the liver of WT mice exposed to FS-induced peritonitis. The absence of the A2A receptor increases the survival rate in mice exposed to polymicrobial sepsis. This outcome was associated with both hemodynamic compensation and enhanced anti-bacterial response.
Assuntos
Peritonite/metabolismo , Receptor A2A de Adenosina/metabolismo , Sepse/metabolismo , Animais , Pressão Sanguínea/fisiologia , Modelos Animais de Doenças , Camundongos , Camundongos Knockout , Peritonite/genética , Peritonite/microbiologia , Peritonite/mortalidade , Receptor A2A de Adenosina/genética , Sepse/genética , Sepse/mortalidade , Taxa de SobrevidaRESUMO
Estrogenic steroids and adenosine A2A receptors promote the wound healing and angiogenesis processes. However, so far, it is unclear whether estrogen may regulate the expression and pro-angiogenic activity of A2A receptors. Using in vivo analyses, we showed that female wild type (WT) mice have a more rapid wound healing process than female or male A2A-deficient mice (A2AKO) mice. We also found that pulmonary endothelial cells (mPEC) isolated from female WT mice showed higher expression of A2A receptor than mPEC from male WT mice. mPEC from female WT mice were more sensitive to A2A-mediated pro-angiogenic response, suggesting an ER and A2A crosstalk, which was confirmed using cells isolated from A2AKO. In those female cells, 17ß-estradiol potentiated A2A-mediated cell proliferation, an effect that was inhibited by selective antagonists of estrogen receptors (ER), ERα, and ERß. Therefore, estrogen regulates the expression and/or pro-angiogenic activity of A2A adenosine receptors, likely involving activation of ERα and ERß receptors. Sexual dimorphism in wound healing observed in the A2AKO mice process reinforces the functional crosstalk between ER and A2A receptors.
Assuntos
Estradiol/farmacologia , Receptor alfa de Estrogênio/genética , Receptor beta de Estrogênio/genética , Neovascularização Fisiológica/efeitos dos fármacos , Receptor A2A de Adenosina/genética , Ferimentos Penetrantes/genética , Adenosina/análogos & derivados , Adenosina/farmacologia , Animais , Proliferação de Células/efeitos dos fármacos , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Receptor alfa de Estrogênio/antagonistas & inibidores , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/antagonistas & inibidores , Receptor beta de Estrogênio/metabolismo , Feminino , Regulação da Expressão Gênica , Pulmão/citologia , Pulmão/metabolismo , Masculino , Camundongos , Camundongos Knockout , Neovascularização Fisiológica/genética , Fenetilaminas/farmacologia , Pirazóis/farmacologia , Pirimidinas/farmacologia , Receptor Cross-Talk , Receptor A2A de Adenosina/metabolismo , Fatores Sexuais , Transdução de Sinais , Cicatrização/efeitos dos fármacos , Cicatrização/genética , Ferimentos Penetrantes/tratamento farmacológico , Ferimentos Penetrantes/metabolismo , Ferimentos Penetrantes/patologiaRESUMO
For many years, cardiovascular disease (CVD) has been the leading cause of death around the world. Often associated with CVD are comorbidities such as obesity, abnormal lipid profiles and insulin resistance. Insulin is a key hormone that functions as a regulator of cellular metabolism in many tissues in the human body. Insulin resistance is defined as a decrease in tissue response to insulin stimulation thus insulin resistance is characterized by defects in uptake and oxidation of glucose, a decrease in glycogen synthesis, and, to a lesser extent, the ability to suppress lipid oxidation. Literature widely suggests that free fatty acids are the predominant substrate used in the adult myocardium for ATP production, however, the cardiac metabolic network is highly flexible and can use other substrates, such as glucose, lactate or amino acids. During insulin resistance, several metabolic alterations induce the development of cardiovascular disease. For instance, insulin resistance can induce an imbalance in glucose metabolism that generates chronic hyperglycemia, which in turn triggers oxidative stress and causes an inflammatory response that leads to cell damage. Insulin resistance can also alter systemic lipid metabolism which then leads to the development of dyslipidemia and the well-known lipid triad: (1) high levels of plasma triglycerides, (2) low levels of high-density lipoprotein, and (3) the appearance of small dense low-density lipoproteins. This triad, along with endothelial dysfunction, which can also be induced by aberrant insulin signaling, contribute to atherosclerotic plaque formation. Regarding the systemic consequences associated with insulin resistance and the metabolic cardiac alterations, it can be concluded that insulin resistance in the myocardium generates damage by at least three different mechanisms: (1) signal transduction alteration, (2) impaired regulation of substrate metabolism, and (3) altered delivery of substrates to the myocardium. The aim of this review is to discuss the mechanisms associated with insulin resistance and the development of CVD. New therapies focused on decreasing insulin resistance may contribute to a decrease in both CVD and atherosclerotic plaque generation.
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Glicemia/metabolismo , Doenças Cardiovasculares/sangue , Endotélio Vascular/metabolismo , Transtornos do Metabolismo de Glucose/sangue , Resistência à Insulina , Insulina/sangue , Animais , Biomarcadores/sangue , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/fisiopatologia , Comorbidade , Dislipidemias/sangue , Dislipidemias/epidemiologia , Dislipidemias/fisiopatologia , Endotélio Vascular/fisiopatologia , Transtornos do Metabolismo de Glucose/epidemiologia , Transtornos do Metabolismo de Glucose/fisiopatologia , Humanos , Inflamação/sangue , Inflamação/epidemiologia , Inflamação/fisiopatologia , Mediadores da Inflamação/sangue , Lipídeos/sangue , Prognóstico , Fatores de Risco , Transdução de SinaisRESUMO
We aim to investigate whether A2A/nitric oxide-mediated regulation of vascular endothelial growth factor (VEGF) expression is impaired in feto-placental endothelial cells from late-onset pre-eclampsia. Cultures of human umbilical vein endothelial cells (HUVECs) and human placental microvascular endothelial cells (hPMECs) from normal and pre-eclamptic pregnancies were used. Assays by using small interference RNA (siRNA) for A2A were performed, and transfected cells were used for estimation of messenger RNA (mRNA) levels of VEGF, as well as for cell proliferation and angiogenesis in vitro. CGS-21680 (A2A agonist, 24 h) increases HUVEC and hPMEC proliferation in a dose response manner. Furthermore, similar to CGS-21680, the nitric oxide donor, S-nitroso-N-acetyl-penicillamine oxide (SNAP), increased cell proliferation in a dose response manner (logEC50 10-9.2 M). In hPMEC, CGS-21680 increased VEGF protein levels in both normal (â¼1.5-fold) and pre-eclamptic pregnancies (â¼1.2-fold), an effect blocked by the A2A antagonist, ZM-241385 (10-5 M) and the inhibitor of NO synthase, N ω-nitro-L-arginine methyl ester hydrochloride (L-NAME). Subsequently, SNAP partially recovered cell proliferation and in vitro angiogenesis capacity of cells from normal pregnancies exposed to siRNA for A2A. CGS-21680 also increased (â¼1.5-fold) the level of VEGF mRNA in HUVEC from normal pregnancies, but not in pre-eclampsia. Additionally, transfection with siRNA for A2A decrease (â¼30 %) the level of mRNA for VEGF in normal pregnancy compared to untransfected cells, an effect partially reversed by co-incubation with SNAP. The A2A-NO-VEGF pathway is present in endothelium from microcirculation and macrocirculation in both normal and pre-eclamptic pregnancies. However, NO signaling pathway seems to be impaired in HUVEC from pre-eclampsia.
Assuntos
Endotélio Vascular/metabolismo , Pré-Eclâmpsia/metabolismo , Receptor A2A de Adenosina/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Adenosina/análogos & derivados , Adenosina/farmacologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Endotélio Vascular/efeitos dos fármacos , Feminino , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Óxido Nítrico/metabolismo , Fenetilaminas/farmacologia , Gravidez , Transdução de Sinais/efeitos dos fármacosRESUMO
Human endothelial progenitor cells (hEPC) are adult stem cells located in the bone marrow and peripheral blood. Studies have indicated that hEPC play an important role in the recovery and repair of injured endothelium, however, their quantity and functional capacity is reduced in several diseases including hypercholesterolemia. Recently, it has been demonstrated that hEPC express lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) and its activation by oxidized low-density lipoprotein (ox-LDL) induces cellular dysfunction and apoptosis. This study aimed to investigate whether overexpression of LOXIN, a truncated isoform of LOX-1 that acts as a dominant negative, plays a protective role against ox-LDL-induced apoptosis in hEPC. Human endothelial progenitor cells exposed to ox-LDL showed a significant increase in LOX-1 expression, and apoptosis began at ox-LDL concentrations above 50 µg/mL. All hEPC apoptosed at 200 µg/mL ox-LDL. High LOXIN expression was generated using adenoviral systems in hEPC and SiHa cells transduced with 100 colony-forming units per cell. Transduced LOXIN localized to the plasma membrane and blocked ox-LDL uptake mediated by LOX-1. Overexpression of LOXIN protected hEPC from ox-LDL-induced apoptosis, and therefore maybe a novel way of improving hEPC function and quantity. These results suggest that adenoviral vectors of LOXIN may provide a possible treatment for diseases related to ox-LDL and vascular endothelium dysfunction, including atherosclerosis.
Assuntos
Apoptose/genética , Células Progenitoras Endoteliais/citologia , Regulação da Expressão Gênica/genética , Receptores Depuradores Classe E/genética , Células Cultivadas , Endotélio Vascular/patologia , Humanos , Lipoproteínas LDL/administração & dosagem , Lipoproteínas LDL/metabolismoRESUMO
BACKGROUND: Human endothelial progenitor cells (hEPC) correspond to a subtype of stem cells which, in the presence of angiogenic stimuli, can be mobilized from bone marrow to circulation and then recruited to the damaged endothelium, where they differentiate into mature endothelial cells. High-density lipoproteins (HDL) increase the level and functionality (proliferation, migration, differentiation, angiogenesis capacity) of circulating hEPC; however, the contribution of receptors for HDL and/or apolipoprotein A-I (apoA-I), the main HDL apolipoprotein, in these effects is still unclear. On mature endothelial cells, the cell surface F1-ATP synthase has been previously characterized as a high affinity receptor of apoA-I, whereas the scavenger receptor SR-BI mainly binds with fully lipidated HDL and displays a poor affinity for lipid-free apoA-I. Furthermore, it was shown that apoA-I binding to surface ATP synthase on mature endothelial cells promotes cell proliferation, whereas inhibits apoptosis. In this work, we aimed to determine the effect of apoA-I in the proliferation and the angiogenic capacity of early hEPC, and the contribution of the cell surface ATP synthase in these events. RESULTS: We first evidenced that early hEPC express the ATP synthase at the surface of nonpermeabilized cells, where it is not colocalized with MitoTracker, a mitochondria marker. ApoA-I (50 µg/mL) increases hEPC proliferation (+14.5%, p<0.001) and potentiates the effect of hEPC on a cellular model of angiogenesis, with an increase of +31% (p<0.01) in branch point counting and in tubule length. These effects of apoA-I were totally reversed in the presence of ATP synthase inhibitors, such as IF1 or oligomycin, whereas the inhibition of the HDL receptor, SR-BI, partially inhibits these events. CONCLUSIONS: These results provide the first evidence that surface ATP synthase is expressed on early hEPC, where it mediates apoA-I effects in hEPC proliferation and in angiogenesis. This knowledge could be helpful for future investigations focused on the regulation of the number and functionality of these cells and in the development of new therapies for the treatment of diseases, such as cardiovascular disease.
Assuntos
Apolipoproteína A-I/fisiologia , Células Endoteliais/metabolismo , ATPases Translocadoras de Prótons/metabolismo , Adulto , Apoptose , Membrana Celular/metabolismo , Proliferação de Células , Células Progenitoras Endoteliais/metabolismo , Feminino , Voluntários Saudáveis , Humanos , Lipoproteínas HDL/metabolismo , Masculino , Microscopia Confocal , Mitocôndrias/metabolismo , Neovascularização Fisiológica , Receptores de Lipoproteínas/metabolismo , Células-Tronco/citologia , Adulto JovemRESUMO
Gestational diabetes mellitus (GDM) is a hyperglycemic state that is typically diagnosed by an oral glucose tolerance test (OGTT), which is unpleasant, time-consuming, has low reproducibility, and results are tardy. The machine learning (ML) predictive models that have been proposed to improve GDM diagnosis are usually based on instrumental methods that take hours to produce a result. Near-infrared (NIR) spectroscopy is a simple, fast, and low-cost analytical technique that has never been assessed for the prediction of GDM. This study aims to develop ML predictive models for GDM based on NIR spectroscopy, and to evaluate their potential as early detection or alternative screening tools according to their predictive power and duration of analysis. Serum samples from the first trimester (before GDM diagnosis) and the second trimester (at the time of GDM diagnosis) of pregnancy were analyzed by NIR spectroscopy. Four spectral ranges were considered, and 80 mathematical pretreatments were tested for each. NIR data-based models were built with single- and multi-block ML techniques. Every model was subjected to double cross-validation. The best models for first and second trimester achieved areas under the receiver operating characteristic curve of 0.5768 ± 0.0635 and 0.8836 ± 0.0259, respectively. This is the first study reporting NIR-spectroscopy-based methods for the prediction of GDM. The developed methods allow for prediction of GDM from 10 µL of serum in only 32 min. They are simple, fast, and have a great potential for application in clinical practice, especially as alternative screening tools to the OGTT for GDM diagnosis.
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Hydrogels are three-dimensional crosslinked materials known for their ability to absorb water, exhibit high flexibility, their biodegradability and biocompatibility, and their ability to mimic properties of different tissues in the body. However, their application is limited by inherent deficiencies in their mechanical properties. To address this issue, reduced graphene oxide (rGO) and tannins (TA) were incorporated into alginate hydrogels (Alg) to evaluate the impact of the concentration of these nanomaterials on mechanical and adhesive, as well as cytotoxicity and wound-healing properties. Tensile mechanical tests demonstrated improvements in tensile strength, elastic modulus, and toughness upon the incorporation of rGO and TA. Additionally, the inclusion of these materials allowed for a greater energy dissipation during continuous charge-discharge cycles. However, the samples did not exhibit self-recovery under environmental conditions. Adhesion was evaluated on pig skin, revealing that higher concentrations of rGO led to enhanced adhesion, while the concentration of TA did not significantly affect this property. Moreover, adhesion remained consistent after 10 adhesion cycles, and the contact time before the separation between the material and the surface did not affect this property. The materials were not cytotoxic and promoted healing in human fibroblast-model cells. Thus, an Alg/rGO/TA hydrogel with enhanced mechanical, adhesive, and wound-healing properties was successfully developed.
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In this study, an innovative conductive hybrid biomaterial was synthetized using collagen (COL) and reduced graphene oxide (rGO) in order for it to be used as a wound dressing. The hydrogels were plasticized with glycerol and enzymatically cross-linked with horseradish peroxidase (HRP). A successful interaction among the components was demonstrated by FTIR, XRD, and XPS. It was demonstrated that increasing the rGO concentration led to higher conductivity and negative charge density values. Moreover, rGO also improved the stability of hydrogels, which was expressed by a reduction in the biodegradation rate. Furthermore, the hydrogel's stability against the enzymatic action of collagenase type I was also strengthened by both the enzymatic cross-linking and the polymerization of dopamine. However, their absorption capacity, reaching values of 215 g/g, indicates the high potential of the hydrogels to absorb fluids. The rise of these properties positively influenced the wound closure process, achieving an 84.5% in vitro closure rate after 48 h. These findings clearly demonstrate that these original composite biomaterials can be a viable choice for wound healing purposes.
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To investigate whether fetal endothelial cell proliferation and migration are modulated by the A2A adenosine receptor (A2AAR), nitric oxide (NO) and the vascular endothelial growth factor (VEGF) signaling pathway, we isolated human umbilical vein endothelial cells from normal pregnancy (n = 23), preterm delivery (n = 4), and late-onset (LOPE, n = 10) and early-onset preeclampsia (EOPE, n = 8). We used the non-selective adenosine receptor agonist (NECA) and the selective agonist (CGS-21680) and/or selective antagonist (ZM-241385) for A2AAR. Also, the nitric oxide synthase (NOS) inhibitor, L-NAME, was used in co-incubation with CGS-21680. Compared to normal pregnancy, EOPE exhibited low cell proliferation and migration associated with reduced expressions of A2AAR and VEGF and NO synthesis (i.e., total and phosphorylated serine(1177) endothelial NOS and nitrite formation). In contrast, LOPE exhibited the opposite behavior in all these markers compared to normal pregnancy or EOPE. Cell proliferation and migration were increased by CGS-21680 (or NECA) in all analyzed groups (EOPE>LOPE>normal pregnancy) compared to their respective basal conditions, an effect that was associated with high NO and VEGF synthesis and blocked by ZM-241385 with significantly different IC50 for each group (EOPE>LOPE>normal pregnancy). The differences seem independent of gestational age. L-NAME blocked the CGS-21680-mediated cell proliferation and migration in normal pregnancy and LOPE (IC50 = 36.2 ± 2.5 and 8.6 ± 2.2 nM, respectively) as well as the VEGF expression in normal pregnancy. Therefore, the A2AAR/NO/VEGF signaling pathway exhibits a pro-angiogenic effect in normal pregnancies and LOPE, whereas impairment in this pathway seems related to the reduced angiogenic capacity of the fetal endothelium in EOPE.
Assuntos
Células Endoteliais/metabolismo , Óxido Nítrico/metabolismo , Pré-Eclâmpsia/metabolismo , Receptor A2A de Adenosina/metabolismo , Transdução de Sinais/fisiologia , Fator A de Crescimento do Endotélio Vascular/fisiologia , Adenosina/metabolismo , Western Blotting , Movimento Celular/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Feminino , Feto , Humanos , Imuno-Histoquímica , Pré-Eclâmpsia/fisiopatologia , Gravidez , Agonistas do Receptor Purinérgico P1/farmacologia , Antagonistas de Receptores Purinérgicos P1/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Veias UmbilicaisRESUMO
Current global challenges of the 21st century promote STEAM (science, technology, engineering, arts and mathematics) education and digitalization as a means for humans to be the central actors in the construction of a sustainable society that favors a sense of worth and global wellbeing. In this scenario, new educational technology tools and immersive learning affordances (possibilities), offer unprecedented potential for the design of smart and dynamic learning systems and contexts that can enhance learning processes across varied audiences and educational settings. However, current STEAM education practice lacks attention to equipping all citizens with the necessary skills to use digital technologies in an ethical, critical and creative way. This gap calls for attention in design processes, principles and practices that are attentive to ethical considerations and values-based approaches. On the other hand, in its formulation STEAM as an educational approach is framed in four fundamental pillars: creativity, inclusion, citizenship and emerging technologies, which also put attention on the inclusion of disadvantaged and underrepresented social groups during STEAM education design. Following an apparent need to explore ethical and inclusive design in STEAM education, and inspired in the 4E cognition framework, ethical enactivism and embodied and ecosomaesthetics experience design, here we propose a theoretical framework grounded on systems thinking for the design of smart and dynamic STEAM learning systems and settings. The framework is aimed at STEAM educational psychologists, educational technologists, learning designers and educational practitioners who wish to address the global challenges of 21st century education by means of creative, innovative and inclusive education design.
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BACKGROUND: Hematopoiesis, the process of blood cell formation involves on a complex network of transcription factors. Among them, the CCAAT-enhancer-binding protein alpha (CEBPA) plays a crucial role in maintaining the balance between myeloid proliferation and differentiation. Imbalances in this network can lead to disrupted differentiation and contribute to the development of malignant diseases. AIM: Understanding of disease development and explore potential therapeutic strategies for hematological disorders associated CEPBA gen. MATERIALS AND METHODS: The research involved a comprehensive analysis of CEBPA gene mutations in the context of acute myeloid leukemia (AML). This encompassed a thorough exploration of point mutations and double mutations in AML patients. RESULTS: In the context of acute myeloid leukemia (AML), mutations in the CEBPA gene, especially point mutations, are frequently observed. A significant number of AML patients present with double mutations in CEBPA, which have been linked to a more favorable prognosis in terms of overall survival and event-free survival. These patients also tend to exhibit enhanced responsiveness to treatment. DISCUSSION: Unraveling the intricate interplay of transcription factors, particularly CEBPA, holds significant implications for decoding the mechanisms governing hematopoiesis. This understanding offers a potential avenue for deciphering disease development and devising novel therapeutic strategies for hematological disorders. CONCLUSION: The findings underscore that CEBPA mutations correlate with enhanced overall survival and event-free survival, with relevance to those presenting within the bZip framework. This knowledge may contribute to advancing personalized treatments for hematological conditions.
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Leucemia Mieloide Aguda , Humanos , Prognóstico , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Mutação , Proteínas Estimuladoras de Ligação a CCAAT/genética , Fatores de Transcrição/genéticaRESUMO
Children carrying the minor allele 'A' at the fat mass and obesity-associated protein (FTO) gene have higher obesity prevalence. We examined the link between FTO rs9939609 polymorphism and plasma adiponectin and the mediating role of body adiposity, in a cross-sectional study comprising 323 children aged 6-11 years. Adiponectin and FTO genotypes were assessed using a commercial kit and a real-time polymerase chain reaction with high-resolution melting analysis, respectively. Body adiposity included body mass index z-score, body fat percentage and waist-to-hip ratio. To investigate adiponectin (outcome) associations with FTO and adiposity, linear regressions were implemented in additive models and across genotype categories, adjusting for sex, age and Tanner's stage. Using mediation analysis, we determined the proportion of the association adiponectin-FTO mediated by body adiposity. Lower adiponectin concentrations were associated with one additional risk allele (ßadditive = -0.075 log-µg/mL [-0.124; -0.025]), a homozygous risk genotype (ßAA/TT = -0.150 [-0.253; -0.048]) and a higher body mass index z-score (ß = -0.130 [-0.176; -0.085]). Similar results were obtained for body fat percentage and waist-to-hip ratio. Body adiposity may mediate up to 29.8% of the FTO-adiponectin association. In conclusion, FTO rs9939609-related differences in body adiposity may partially explain lower adiponectin concentrations. Further studies need to disentangle the biological pathways independent from body adiposity.
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The pediatric population has various criteria for measuring metabolic syndrome (MetS). The diversity of consensus for diagnosis has led to different non-comparable reported prevalence. Given the increase in its prevalence in pediatric ages, it is necessary to develop efficient methods to encourage early detection. Consequently, early screening for the risk of MetS could favor timely action in preventing associated comorbidities in adulthood. This study aimed to establish the diagnostic capacity of models that use non-invasive (anthropometric) and invasive (serum biomarkers) variables for the early detection of MetS in Chilean children. A cross-sectional study was carried out on 220 children aged 6 to 11. Multivariate logistic regressions and discriminant analyses were applied to determine the diagnostic capacity of invasive and non-invasive variables. Based on these results, four diagnostic models were created and compared: (i) anthropometric, (ii) hormonal (insulin, leptin, and adiponectin), (iii) Lipid A (high-density cholesterol lipoprotein [HDL-c] and triglycerides [TG]) and (iv) Lipid B (TG/HDL-c). The prevalence of MetS was 26.8%. Lipid biomarkers (HDL-c and TG) and their ratio (TG/HDL-c) presented higher diagnostic capacity, above 80%, followed by body mass index (BMI, 0.71-0.88) and waist-to-height ratio (WHtR, 0.70-0.87). The lipid model A was the most accurate (sensitivity [S] = 62.7%, specificity [E] = 96.9%, validity index 87.7%), followed by the anthropometric model (S = 69.5%, E = 88.8% and validity index = 83.6%). In conclusion, detecting MetS was possible through invasive and non-invasive methods tested in overweight and obese children. The proposed models based on anthropometric variables, or serum biomarkers of the lipid model A, presented acceptable validity indices. Moreover, they were higher than those that measured adipokines, leptin, and adiponectin. The anthropometric model was the most cost-effective and easy to apply in different environments.
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In this study, a conductive composite material, based on graphene oxide (GO), nanocellulose (CNF), and tannins (TA) from pine bark, reduced using polydopamine (PDA), was developed for wound dressing. The amount of CNF and TA was varied in the composite material, and a complete characterization including SEM, FTIR, XRD, XPS, and TGA was performed. Additionally, the conductivity, mechanical properties, cytotoxicity, and in vitro wound healing of the materials were evaluated. A successful physical interaction between CNF, TA, and GO was achieved. Increasing CNF amount in the composite reduced the thermal properties, surface charge, and conductivity, but its strength, cytotoxicity, and wound healing performance were improved. The TA incorporation slightly reduced the cell viability and migration, which may be associated with the doses used and the extract's chemical composition. However, the in-vitro-obtained results demonstrated that these composite materials can be suitable for wound healing.
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Ovarian cancer presents a significant challenge due to its high rate of chemoresistance, which complicates the effectiveness of drug-response therapy. This study provides a comprehensive metabolomic analysis of ovarian cancer cell lines OVCAR-3 and SK-OV-3, characterizing their distinct metabolic landscapes. Metabolomics coupled with chemometric analysis enabled us to discriminate between the metabolic profiles of these two cell lines. The OVCAR-3 cells, which are sensitive to doxorubicin (DOX), exhibited a preference for biosynthetic pathways associated with cell proliferation. Conversely, DOX-resistant SK-OV-3 cells favored fatty acid oxidation for energy maintenance. Notably, a marked difference in glutathione (GSH) metabolism was observed between these cell lines. Our investigations further revealed that GSH depletion led to a profound change in drug sensitivity, inducing a shift from a cytostatic to a cytotoxic response. The results derived from this comprehensive metabolomic analysis offer potential targets for novel therapeutic strategies to overcome drug resistance. Our study suggests that targeting the GSH pathway could potentially enhance chemotherapy's efficacy in treating ovarian cancer.