Browsing by Author "Farías Jofré, Marcelo Enrique"

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    Adenosine and preeclampsia
    (2017) Salsoso Rodríguez, M. Rocío; Farías Jofré, Marcelo Enrique; Gutiérrez, J.; Pardo, F.; Chiarello, D.; Toledo, F.; Leiva Mendoza, Andrea Alejandra; Mate, A.; Vazquez, C.; Sobrevía Luarte, Luis Alberto
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    Assessment of in vivo fetal growth and placental vascular function in a novel intrauterine growth restriction model of progressive uterine artery occlusion in guinea pigs
    (2016) Krause B.; Herrera, E.; Alegría, R.; Farías Jofré, Marcelo Enrique; Díaz López, F.; Hernández, C.; Uauy, Ricardo; Regnault, T.; Casanello Toledo, Paola Cecilia; Krause Leyton, Bernardo
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    Ateroesclerosis subclínica y síndrome metabólico en niños
    (2013) Arnáiz Gómez, Pilar; Barja Y., Salesa; Villarroel del Pino, Luis A.; Domínguez, Angélica; Godoy J., Iván; Castillo Valenzuela, Oscar; Farías Jofré, Marcelo Enrique; Mardones, Francisco
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    Clarithromycin prevents preterm birth and neonatal mortality by dampening alarmin-induced maternal–fetal infammation in mice
    (2022) Galaz, José; Romero, Roberto; Arenas-Hernandez, Marcia; Farías Jofré, Marcelo Enrique; Motomura, Kenichiro; Liu, Zhenjie; Kawahara, Naoki; Demery-Poulos, Catherine; Liu, Tzu N.; Padron, Justin; Panaitescu, Bogdan; Gomez-Lopez, Nardhy
    Background: One of every four preterm neonates is born to a woman with sterile intra-amniotic inflammation (inflammatory process induced by alarmins); yet, this clinical condition still lacks treatment. Herein, we utilized an established murine model of sterile intra-amniotic inflammation induced by the alarmin high-mobility group box-1 (HMGB1) to evaluate whether treatment with clarithromycin prevents preterm birth and adverse neonatal outcomes by dampening maternal and fetal inflammatory responses. Methods: Pregnant mice were intra-amniotically injected with HMGB1 under ultrasound guidance and treated with clarithromycin or vehicle control, and pregnancy and neonatal outcomes were recorded (n = 15 dams each). Additionally, amniotic fluid, placenta, uterine decidua, cervix, and fetal tissues were collected prior to preterm birth for determination of the inflammatory status (n = 7–8 dams each). Results: Clarithromycin extended the gestational length, reduced the rate of preterm birth, and improved neonatal mortality induced by HMGB1. Clarithromycin prevented preterm birth by interfering with the common cascade of parturition as evidenced by dysregulated expression of contractility-associated proteins and inflammatory mediators in the intra-uterine tissues. Notably, clarithromycin improved neonatal survival by dampening inflammation in the placenta as well as in the fetal lung, intestine, liver, and spleen. Conclusions: Clarithromycin prevents preterm birth and improves neonatal survival in an animal model of sterile intra-amniotic inflammation, demonstrating the potential utility of this macrolide for treating women with this clinical condition, which currently lacks a therapeutic intervention.
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    d-glucose increased l-arginine transport and nitric oxide synthesis through an autocrine mechanism involving TGF-β1 and TGF-β receptor II (TβRII) in human umbilical vein endothelium
    (2006) Vásquez, Rodrigo; Farías Jofré, Marcelo Enrique; San Martín, Rody; Casanello Toledo, Paola Cecilia; Sobrevía Luarte, Luis Alberto
    High D-glucose increases L-arginine transport, nitric oxide (NO) synthesis, and release of Transforming Growth Factor β1 (TGF-β1) in human umbilical vein endothelium (HUVEC). Changes in cell proliferation in response to D-glucose have been explained by a TGF-β1 autocrine mechanism in this cell type. However, the involvement of TGF-β1 and TGF-β1 receptor II (TβRII) on D-glucose effect on endothelial L-arginine/NO pathway has not been reported. L-[3H]Arginine transport (100 μM, 2 μCi/ml) and endothelial NO synthase (eNOS) activity [L-[3H]citrulline formation from L-[3H]arginine, 4 μCi/ml, 30 min, ± NG-nitro-L-arginine methyl ester (L-NAME), 100 μM] were determined in primary cultures of HUVEC exposed (6 h) to 5 mM (normal) or 25 mM (high) D-glucose, in absence or presence of TGF-β1 (2 ng/ml). Supernatant TGF-β1 level was measured by ELISA. HUVEC were infected (2% sera for 12 h) with an adenovirus expressing a negative dominant truncated TβRII (AdTβRIIt). Expression of TβRIIt was determined by Western blot. High D-glucose and TGF-β1 [half maximal effect (Ks): 0.28 ng/ml] increased L-arginine transport, effects that were significantly (P< 0.005) reduced in AdTβRIIt infected cells. L-Arginine transport was not further increased in non-infected infected cells co-incubated with high D-glucose and TGF-β1. However, L-arginine transport in AdTβRIIt infected cells co-incubated with these molecules was reduced. High D-glucose and TGF-β1 increased L-citrulline formation only in non-infected cells. High D-glucose also increased supernatant TGF-β1 level. We propose that stimulation of endothelial L-arginine/NO pathway by high D-glucose could result from a mechanism involving activation of TβRII by TGF-β1 as a consequence of increased release of this growth factor in HUVEC. Supported by FONDECYT 1030781 & 1030607 (Chile). R.V. holds a DIPUC-School of Medicine PhD (Chile) fellowship. M.F. holds CONICYT and School of Medicine–PhD (Chile) fellowships
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    D-Glucose increases the expression and activity of hCAT-1 and Spl binding to SLC7A1 promoter in human umbilical vein endothelium
    (2008) González Ortiz, Marcelo Andrés; Farías Jofré, Marcelo Enrique; Casanello Toledo, Paola Cecilia; Sobrevía Luarte, Luis Alberto
    L-Arginine is mainly transported by the human cationic amino acid transporter 1 (hCAT-1, protein codified by the gene SLC7A1) in human umbilical vein endothelial cells (HUVEC). hCAT-1 mediated L-arginine transport and nitric oxide (NO) synthesis are increased by 25 mM D-glucose in this cell type. Since Sp1 is a transcription factor activated by NO, we studied whether high D-glucose effect on transport was due to altered expression of hCAT-1 and abundance and activity of the transcription factor Sp1 in primary cultures of HUVEC. D-Glucose (25 mM, 24 hours) increased (~3.2 fold) the maximal velocity (Vmax), without altering the apparent Km, of L-arginine transport compared with cells in 5 mM D-glucose. High D-glucose also increased the hCAT-1 mRNA number of copies (~5-fold) and protein abundance (~2-fold), and Sp1 nuclear abundance and binding to SLC7A1 promoter region (−177 to −103 bp from ATG). Thus, the stimulatory effect of D-glucose on L-arginine transport could result from increased expression of hCAT-1 due to increased activity of Sp1 on the promoter of SLC7A1 in HUVEC.
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    Differential immunophenotype of circulating monocytes from pregnant women in response to viral ligands
    (2023) Farías Jofré, Marcelo Enrique; Romero, Roberto; Xu, Yi; Levenson, Dustyn; Tao, Li; Kanninen, Tomi; Galaz, Jose; Arenas-Hernandez, Marcia; Liu, Zhenjie; Miller, Derek; Bhatti, Gaurav; Seyerle, Megan; Tarca, Adi L.; Gomez-Lopez, Nardhy
    Background Viral infections during pregnancy can have deleterious effects on mothers and their offspring. Monocytes participate in the maternal host defense against invading viruses; however, whether pregnancy alters monocyte responses is still under investigation. Herein, we undertook a comprehensive in vitro study of peripheral monocytes to characterize the differences in phenotype and interferon release driven by viral ligands between pregnant and non-pregnant women. Methods Peripheral blood was collected from third-trimester pregnant (n = 20) or non-pregnant (n = 20, controls) women. Peripheral blood mononuclear cells were isolated and exposed to R848 (TLR7/TLR8 agonist), Gardiquimod (TLR7 agonist), Poly(I:C) (HMW) VacciGrade™ (TLR3 agonist), Poly(I:C) (HMW) LyoVec™ (RIG-I/MDA-5 agonist), or ODN2216 (TLR9 agonist) for 24 h. Cells and supernatants were collected for monocyte phenotyping and immunoassays to detect specific interferons, respectively. Results The proportions of classical (CD14hiCD16−), intermediate (CD14hiCD16+), non-classical (CD14loCD16+), and CD14loCD16− monocytes were differentially affected between pregnant and non-pregnant women in response to TLR3 stimulation. The proportions of pregnancy-derived monocytes expressing adhesion molecules (Basigin and PSGL-1) or the chemokine receptors CCR5 and CCR2 were diminished in response to TLR7/TLR8 stimulation, while the proportions of CCR5− monocytes were increased. Such differences were found to be primarily driven by TLR8 signaling, rather than TLR7. Moreover, the proportions of monocytes expressing the chemokine receptor CXCR1 were increased during pregnancy in response to poly(I:C) stimulation through TLR3, but not RIG-I/MDA-5. By contrast, pregnancy-specific changes in the monocyte response to TLR9 stimulation were not observed. Notably, the soluble interferon response to viral stimulation by mononuclear cells was not diminished in pregnancy. Conclusions Our data provide insight into the differential responsiveness of pregnancy-derived monocytes to ssRNA and dsRNA, mainly driven by TLR8 and membrane-bound TLR3, which may help to explain the increased susceptibility of pregnant women to adverse outcomes resulting from viral infection as observed during recent and historic pandemics.
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    Dislipidemias en escolares chilenos: prevalencia y factores asociados
    (2015) Barja Y., Salesa; Arnáiz Gómez, Pilar; Villarroel del Pino, Luis A.; Domínguez de Landa, María Angélica; Castillo Valenzuela, Oscar; Farías Jofré, Marcelo Enrique; Mardones S., Francisco
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    Docohexaenoic acid improves the reduced umbilical vein relaxation observed in the offspring of pregnancies with maternal obesity
    (2017) Farías Jofré, Marcelo Enrique; Villalobos Labra, Roberto Esteban; Solari Gajardo, Sandra; Aguirre Polanco, Carolina; Samith Catalán, Bárbara Patricia; Rojas Vidal, María José
    Background and objectives: Maternal obesity (MO) is associated with increased risk of long term metabolic risk in the offspring (REF), probably involving mechanisms such as early programming of insulin resistance in fetal and neonatal tissues. On the other hand, exposure to the polyunsaturated acid Docohexaenoic acid (DHA) has been related with increased insulin response in multiple cell types. The aims of our study were to evaluate the in vitro effect of DHA on vascular response of umbilical vein to insulin, and the role of the intracellular inhibitory phosphorylation of the insulin receptor substrate-1. Methods: Umbilical cords from normal and MO pregnant woman attending to obstetrics service at the Clinical Hospital of Pontificia Universidad Catolica de Chile were obtained after informed consent. Isolated rings of umbilical vein were used to evaluate vasodilatation capacity by wire-myography, in absence or presence of insulin (10-10 to 10-6 uM, 0-20 min) and DHA (100 uM, 12 h). Primary cultures of human umbilical vein endothelial cells (HUVEC) were used to evaluated phosphorylated and total protein levels of IRS-1 in cells exposed or not to insulin (1 nM, 30 min), in absence or presence of DHA (100 uM, 12 h). 308 Ann Nutr Metab 2017;71(suppl 2):1–1433 Oral Abstracts Results: Insulin produces a significant vasodilation (20%) in umbilical vein rings from normal pregnancies, an effect that was absent in MO-derived umbilical rings. This vasodilator effect of insulin was recovered in umbilical vein rings from MO pregnancies pre-incubated with DHA. In addition, HUVEC from MO pregnancies showed increased levels of IRS-1 phosphorylated in serine307, compared with normal cells, a difference that was reduced by DHA, even in presence of insulin. Conclusions: In vitro addition of DHA recovers the reduced vascular response to insulin in umbilical vein from MO pregnancies, involving a reduction of the inhibitory phosphorylation of IRS in serine307.
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    Early origins of allergy and asthma (ARIES): study protocol for a prospective prenatal birth cohort in Chile.
    (2020) Hernández Vargas, Caroll Daffner; Casanello Toledo, Paola Cecilia; Harris D., Paul R.; Castro Rodríguez, José Antonio; Iturriaga, Carolina; Pérez Mateluna, Guillermo; Farías Jofré, Marcelo Enrique; Urzúa, Marcela; Hernández Carreño, Cherie Francisca; Serrano Honeyman, Carolina; Hernández Vargas, Caroll Daffner; Casanello Toledo, Paola Cecilia; Harris D., Paul R.; Castro Rodríguez, José Antonio; Iturriaga, Carolina; Pérez Mateluna, Guillermo; Farías Jofré, Marcelo Enrique; Urzúa, Marcela; Hernández Carreño, Cherie Francisca; Serrano Honeyman, Carolina
    Abstract Background Growing evidence shows that atopic dermatitis (AD), food allergy (FA), allergic rhinitis, and asthma are largely determined during the first 1000 days (time elapsed from conception to the 2nd birthday). The ARIES birth cohort aims to determine prenatal and perinatal conditions, as well as genetic and epigenetic factors, that participate in the early setting of immune responses, and the role of these in the later determination of the risk of allergic diseases and asthma in the offspring. Methods We have designed a birth cohort of 250 families with prenatal recruitment (~ 14 weeks). We will genotype relevant allergy/asthma-associated variants in trios and will perform immunophenotyping and evaluation of allergy biomarkers in cord blood. At 1 and 2 years of age we will assess if infants have developed allergic sensitization, AD, FA, as well as biomarkers of asthma including the asthma predictive index. We will also evaluate how maternal conditions modify immune programming through epigenetic modifications and will then depict newborn epigenetic cues of allergy/asthma risk. Next, we will assess composition/diversity of maternal gut, placenta, breastmilk and infant gut microbiome and their association with immunophenotype and biomarkers at birth, and clinical outcomes at age 1 and 2. Finally, we plan to assess how environmental exposures (perinatal outdoor and indoor pollution, allergens and endotoxin) affect the incidence of allergic sensitization, AD, FA, and risk of asthma. Discussion The in-depth study of the ARIES birth cohort shall provide crucial information to understand the rising incidence of allergies and asthma in developing countries, and hopefully provide cues on how to prevent and treat these diseases. Trial registration clinicaltrials.gov NCT04186949, retrospectively registered on December 5, 2019.
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    Efecto de la excesiva ganancia de peso corporal según índice de masa corporal sobre los lípidos plasmáticos en el tercer trimestre del embarazo
    (2021) Moya Fariñas, Daniela; Farías Jofré, Marcelo Enrique; Leiva Mendoza, Andrea Alejandra; Pontificia Universidad Católica de Chile. Escuela de Medicina
    Contexto: La ganancia de peso corporal (GP) excesiva durante el embarazo produce alteraciones metabólicas que incrementan el riesgo de efectos adversos. El colesterol total (CT) y LDL circulantes maternos aumentan fisiológicamente durante el embarazo. Sin embargo, un exceso de estos lípidos plasmáticos afecta negativamente la salud vascular fetal. Objetivo: Evaluar el efecto de la ganancia de peso corporal excesiva, según estado de estado nutricional al inicio del embarazo, sobre los lípidos plasmáticos en el tercer trimestre de embarazo sin patologías asociadas. Diseño: Estudio longitudinal retrospectivo. Se recogieron muestras de sangre y se realizaron medidas antropométricas en el periodo pregestacional, durante el embarazo y postparto, según índice de masa corporal (IMC, n=650). Se determinó el perfil lipídico plasmático, y se realizaron correlaciones con IMC y GP. El análisis multivariado se realizó a través de regresión lineal múltiple. Considerando significancia estadística cuando p<0,05. Resultados: Se describieron las típicas trayectorias del perfil lipídico plasmático desde el periodo pregestacional hasta el postparto. En el tercer trimestre de embarazo, se encontró una correlación inversa entre el IMC, el CT y LDL con p= 0,006; p=0,002 respectivamente. Además, existe una correlación directa entre la GP y estos lípidos plasmáticos. En un análisis multivariado, la GP excesiva diferenciada por IMC con el CT y LDL presentó un Β 17,14 ± 6,47 IC 95% 4,42- 29,86 (p=0,008) y Β 11,29 ± 5,61 IC95% 0,28 – 22,31 (p=0,004), respectivamente. Conclusión: El colesterol plasmático total y LDL maternos del tercer trimestre del embarazo se asocian significativamente con la ganancia de peso corporal, lo que apoya la importancia de un adecuado control de peso durante el embarazo.
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    Endothelial dysfunction and reduced insulin response in umbilical vein from the offspring of maternal obesity pregnancies
    (2016) Villalobos Labra, Roberto Esteban; Pizarro, Carolina; Westermeier Lafuente, Francisco David; Sáez Pedraza, Pablo José; Sobrevía Luarte, Luis Alberto; Farías Jofré, Marcelo Enrique
    INTRODUCTION: Maternal obesity (MO) has been recognized as a risk factor for maternal and fetal complications, including offspring´s insulin resistance (IR) later in life. We evaluated the effect of MO in endothelial cells function and umbilical vein vasodilatation in response to insulin. METHODS: Primary cultures of human umbilical vein endothelial cells (HUVEC) and rings were isolated from normal (HUVEC-N) or MO (HUVEC-OB) pregnancies attending to Pontificia Universidad Católica de Chile Hospital. Total and/or phosphorylated level of IRS-1, Akt, MAPK and eNOS, were measured by western blot in protein extracts of cells exposed to insulin (1 nM, 30 min). Wire myography was used to evaluate functional effect of insulin in umbilical vein rings. Cellular nitric oxide (NO) availability was measured using the fluorescent probe diaminofluorescein (DAF). Values are Mean±S.E.M. RESULTS: MO was associated with inhibition of IRS-1 and reduced phosphorylation of Akt (2,24±0,06 vs 6,85±0,12; p<0,01) and MAPK (4,13±0,65 vs 13,12±1,67; p<0,01) in response to insulin, in HUVEC. We found that total eNOS and the activating phosphorylation on Ser1177 was reduced (0,98±0,03 vs 5,45±0,85; p<0,01) in HUVEC-OB compared to HUVEC-N. Conversely, the inhibitory phosphorylation on Thr495 was increased (1,88±0,08 vs 1,51±0,14; p<0,01) in HUVEC-OB. Also, HUVEC-N exposed to insulin (1nM) showed increased levels of NO at 5, 15 and 30 min of incubation, an effect blocked by the inhibitor of NOS L-NAME. In contrast, insulin did not increase NO production in HUVECOB. Finally, vein rings from MO showed abolished relaxation in response to insulin, meanwhile rings from normal pregnancies showed a 20% of insulin dilator effect, which was blocked by L-NAME. CONCLUSIONS: We have shown evidence that MO promotes less vasodilation of umbilical vein in response to insulin, due to an inhibitory state of insulin signaling and eNOS activation, with the consequent absence of insulin-dependent NO production by HUVEC affected by MO.
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    Equilibrative nucleoside transporters in fetal endothelial dysfunction in diabetes mellitus and hyperglycaemia
    (2009) Westermeier Lafuente, Francisco David; Puebla Aracena, Carlos Alberto; Vega Pizarro, José Luis Eduardo; Farías Jofré, Marcelo Enrique; Escudero Orozco, Carlos Alonso; Casanello Toledo, Paola Cecilia; Sobrevía Luarte, Luis Alberto
    Diabetes mellitus types 1 and 2, and gestational diabetes are characterized by abnormal D-glucose metabolism and hyperglycaemia, and induce foetal endothelial dysfunction with implications in adult life increasing the risk of vascular diseases. Synthesis of nitric oxide (NO) and uptake of L-arginine (i.e. the L-arginine/NO signalling pathway) and adenosine (a vasoactive endogenous nucleoside) by the umbilical vein endothelium is altered in pathological pregnancies, including pregnancies with pre-established diabetes mellitus or in gestational diabetes. The mechanisms underlying these alterations include differential expression of equilibrative nucleoside transporters (ENTs), amino acid transporters and NO synthases (NOS). Modulation of ENTs and NOS expression and activity in endothelium involves several signalling molecules, including protein kinase C, mitogen-activated protein kinases p42 and p44, calcium and phosphatidyl inositol 3 kinase. Elevated extracellular D-glucose and diabetes alters human endothelial function. However, information regarding modulation the transport capacity as well as expression of ENTs is limited. This review focuses on the effect of diabetes mellitus and gestational diabetes, and hyperglycaemia on the reported mechanisms described for transcriptional and posttranscriptional regulation of ENTs, and the potential consequences for foetal endothelial function in these pathologies. Recent available information regarding functional consequences of an abnormal environment on the functionality of the endothelium from microvasculature of the human placenta is mentioned. The available information is scarce, but it could contribute to a better understanding of the cell and molecular basis of the altered vascular endothelial function in this pathological conditions, emphasizing the key role of this type of epithelium in fetal-placental function and the normal foetal development and growth.
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    Fetoplacental endothelial dysfunction in maternal hypercholesterolemia and obesity in pregnancy
    (2014) Pardo, F.; Silva Lagos, Luis Alfredo; Salsoso Rodríguez, M. Rocío; Saez, T.; Farías Jofré, Marcelo Enrique; Villalobos Labra, Roberto Esteban; Leiva Mendoza, Andrea Alejandra; Sanhueza, C.; Sobrevía Luarte, Luis Alberto
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    Foetoplacental epigenetic changes associated with maternal metabolic dysfunction
    (2018) Kerr, Bredford; Leiva Mendoza, Andrea Alejandra; Farías Jofré, Marcelo Enrique; Contreras Duarte, Susana de las Mercedes; Toledo, Fernando; Stolzenbach, Francisca; Silva, Luis; Sobrevía Luarte, Luis Alberto
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    Gestational diabetes mellitus is associated with NO and PKC-dependent repressor effect of hCHOP-C/EBPalpha on equilibrative nucleoside transporter 1 expression human umbilical vein endothelium
    (2008) Farías Jofré, Marcelo Enrique; Puebla Aracena, Carlos Alberto; Vega Pizarro, José Luis Eduardo; Pastor-Anglaga, M.; Casanello Toledo, Paola Cecilia; Sobrevía Luarte, Luis Alberto
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    High D-glucose reduces promoter activity of human equilibrative nucleoside transporter 1 in human umbilical vein endothelium
    (2006) Farías Jofré, Marcelo Enrique; San Martin, R; Sobrevía Luarte, Luis Alberto
    Reduction of adenosine uptake by human equilibrative membrane transporters 1 (hENT1) in human umbilical vein endothelial cells (HUVEC) from gestational diabetes, or in HUVEC from normal pregnancies exposed to high extracellular D-glucose, is associated with reduced hENT1 mRNA expression. We studied the effect of high D-glucose on the transcriptional activity of the promoter region of SLC29A1 gene (for hENT1) in HUVEC. Methods: Cells were isolated and cultured in medium 199 (Ethics committee approval and informed patient consent were obtained). Fragments of SLC29A1 promoter (-3100, -2056, -1016 and -697 bp from ATG) were subcloned in pGL3 vector, upstream firefly luciferase reporter gene. Cells were co-transfected with hENT1-promoter constructs and pRL-TK vector by electroporation (320 V, 20 ms) and exposed to 5 or 25 mM D-glucose (24 hrs). Results: firefly/renilla luciferase activity was similar in all constructs transfected in 5 mM D-glucose. However, 25 mM D-glucose was associated with reduced transcriptional activity of sequences -697 to -1016 bp and -2056 to -3100 bp. Conclusions: These results suggest that the reduced hENT1 mRNA level detected in HUVEC exposed to high D-glucose could result from altered transcriptional activity of SLC29A1 promoter, most likely related to activation of repressor sequences of this gene.
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    Hypoxia increases equilibrative nucleoside transporter 2 activity by a transcriptional independent mechanism in human umbilical vein endothelium
    (2006) Torres, A; San Martin, R; Farías Jofré, Marcelo Enrique; Sobrevía Luarte, Luis Alberto; Casanello Toledo, Paola Cecilia
    Low oxygen tension (hypoxia) reduces adenosine transport in several types of mammalian cells. Adenosine transport is mediated by human equilibrative nucleoside transporter 1 (hENT1) and hENT2 in human umbilical vein endothelium (HUVEC), a fetal cell type that grows under 5% O2 (ie. normoxia for this cell type). We studied whether hypoxia alters hENT2 expression and activity in HUVEC. Methods: Cells were cultured (0-24 h) in 5% or 2% O2 (hypoxia), and [3H]adenosine uptake (125 and 500 μM, 4 μCi/ml, 20 s, 37°C) was measured in absence or presence of 100 nM nitrobenzylthioinosine (NBMPR, hENT1 inhibitor). hENT2 mRNA was quantified by real time RT-PCR, and protein abundance was determined by Western blot. SLC29A2 (for hENT2) promoter activity was measured following transfection (electroporation, 320 V, 30 ms) with pGL3 basic plasmid (firefly/renilla luciferase reporter gene) carrying -1477 bp and -587 bp of the promoter sequence. Results: Hypoxia reduced hENT2 mRNA expression (~55%), and promoter activity (~50%), but did not alter hENT2 protein abundance. Adenosine uptake via hENT2 was increased (2-fold) in hypoxia. Conclusions: Adenosine uptake via hENT2 may be modulated by post-translational mechanisms in hypoxia in HUVEC. Supported by FONDECYT 1030781/1030607/7050030. A Torres holds a School of Medicine research fellowship, and M Farías holds a CONICYT-PhD fellowship.
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    Insulin Is a Key Modulator of Fetoplacental Endothelium Metabolic Disturbances in Gestational Diabetes Mellitus
    (2016) Sobrevía Luarte, Luis Alberto; Salsoso Rodríguez, M. Rocío; Fuenzalida Saavedra, Bárbara; Barros Lamus, Eric Raúl; Toledo Valenzuela, Lilian Alejandra; Silva Lagos, Luis Alfredo; Pizarro, C.; Subiabre Morales, Mario Enrique; Villalobos, R.; Araos, J.; Toledo, F.; Gonzalez, M.; Gutierrez, J.; Farías Jofré, Marcelo Enrique; Chiarello, D.; Pardo, F.; Leiva, A.
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    Insulin requires normal expression and signaling of insulin receptor A to reverse gestational diabetes-reduced adenosine transport in human umbilical vein endothelium
    (2015) Westermeier, Francisco; Salomón, Carlos; Farías Jofré, Marcelo Enrique; Arroyo, Pablo; Fuenzalida Saavedra, Bárbara; Sáez, Tamara; Salsoso Rodríguez, M. Rocío; Sanhueza, Carlos; Guzmán-Gutierrez, Enrique; Pardo, Fabián; Leiva Mendoza, Andrea Alejandra; Sobrevía Luarte, Luis Alberto