Browsing by Author "Aguayo, Claudio"

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    Adenosine promoted angiogenesis mediated by the release of small extracellular vesicles from human endothelial progenitor cells
    (2023) Oporto, Katherine; Radojkovic, Claudia; Mellisho, Edwin A.; Zuniga, Felipe; Ormazabal, Valeska; Guzman-Gutierrez, Enrique; Nova-Lamperti, Estefania; Rodriguez-Alvarez, Lleretny; Aranda, Mario; Escudero, Carlos; Aguayo, Claudio
    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 inves-tigate 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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    Comparison of Diagnostic Models to Estimate the Risk of Metabolic Syndrome in a Chilean Pediatric Population: A Cross-Sectional Study
    (2023) Solorzano, Marlin; Granfeldt, Gislaine; Ulloa, Natalia; Molina-Recio, Guillermo; Molina-Luque, Rafael; Aguayo, Claudio; Petermann-Rocha, Fanny; Martorell, Miquel
    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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    High D-Glucose reduces SLC29A1 promoter activity and adenosine transport involving specific protein 1 in human umbilical vein endothelium
    (WILEY, 2008) Puebla, Carlos; Farias, Marcelo; Gonzalez, Marcelo; Vecchiola, Andrea; Aguayo, Claudio; Krause, Bernardo; Pastor Anglada, Marcal; Casanello, Paola; Sobrevia, Luis
    High D-glucose reduces human equilibrative nucleoside transporter 1 (hENT1)-mediated adenosine uptake involving endothelial nitric oxide synthase (eNOS), mitogen-activated protein (MAP) kinase kinases 1 and 2/MAP kinases p42/44 (MEK/ERKs), and protein kinase C (PKC) activation in human umbilical vein endothelium (HUVEC). Since NO represses SLC29A1 gene (hENT1) promoter activity we studied whether D-glucose-reduced hENT1-adenosine transport results from lower SLC29A1 expression in HUVEC primary cultures. HUVEC incubation (24 h) with high D-glucose (25 mM) reduced hENT1-adenosine transport and pGL3-hENT1(-1114) construct SLC29A1 reporter activity compared with normal D-glucose (5 mM). High D-glucose also reduced pGL3-hENT1(-1114) reporter activity compared with cells transfected with pGL3-hENT1(-795) Construct. N-G-nitro-L-arginine methyl ester (L-NAME, NOS inhibitor), PD-98059 (MEK1/2 inhibitor), and/or calphostin C (PKC inhibitor) blocked D-glucose effects. Insulin(1 nM) and phorbol 12-myristate 13-acetate (PMA, 100 nM, PKC activator), but not 4 alpha-phorbol 12,13-didecanoate (4 alpha PDD, 100 nM, PMA less active analogue) reduced hENT1-adenosine transport. L-NAME and PD-98059 blocked insulin effects. L-NAME, PD-98059, and calphostin C increased hENT1 expression without altering protein or mRNA stability. High D-glucose increased Sp1 transcription factor protein abundance and binding to SLC29A1 promoter, phenomena blocked by L-NAME, PD-98059, and calphostin C. Sp1 overexpression reduced SLC29A1 promoter activity in normal D-glucose, an effect reversed by L-NAME and further reduced by S-nitroso-N-acetyl-L,D-penicillamine (SNAP, NO donor) in high D-glucose. Thus, reduced hENT1 -mediated adenosine transport in high D-glucose may result from increased Sp1 binding to SLC29A1 promoter down-regulating hENT1 expression. This phenomenon depends on eNOS, MEK/ERKs, and PKC activity, suggesting potential roles for these molecules in hyperglycemia-associated endothelial dysfunction.
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    Potential role of A2B adenosine receptors on proliferation/migration of fetal endothelium derived from preeclamptic pregnancies
    (2014) Acurio, Jesenia; Troncoso, Felipe; Bertoglia, Patricio; Salomon, Carlos; Aguayo, Claudio; Sobrevía Luarte, Luis Alberto; Escudero, Carlos
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    Pro-angiogenic Role of Insulin: From Physiology to Pathology
    (2017) Escudero, Carlos A.; Herlitz, Kurt; Troncoso, Felipe; Guevara, Katherine; Acurio, Jesenia; Godoy Sánchez, Alejandro Samuel; Aguayo, Claudio; González, Marcelo