Browsing by Author "Owen, Gareth I."
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- Item11 beta-hydroxysteroid dehydrogenase type-2 and type-1 (11 beta-HSD2 and 11 beta-HSD1) and 5 beta-reductase activities in the pathogenia of essential hypertension(HUMANA PRESS INC, 2010) Campino, Carmen; Carvajal, Cristian A.; Cornejo, Javiera; San Martin, Betty; Olivieri, Oliviero; Guidi, Giancesare; Faccini, Giovanni; Pasini, Francesco; Sateler, Javiera; Baudrand, Rene; Mosso, Lorena; Owen, Gareth I.; Kalergis, Alexis M.; Padilla, Oslando; Fardella, Carlos E.Cortisol availability is modulated by several enzymes: 11 beta-HSD2, which transforms cortisol (F) to cortisone (E) and 11 beta-HSD1 which predominantly converts inactive E to active F. Additionally, the A-ring reductases (5 alpha- and 5 beta-reductase) inactivate cortisol (together with 3 alpha-HSD) to tetrahydrometabolites: 5 alpha THF, 5 beta THF, and THE. The aim was to assess 11 beta-HSD2, 11 beta-HSD1, and 5 beta-reductase activity in hypertensive patients. Free urinary F, E, THF, and THE were measured by HPLC-MS/MS in 102 essential hypertensive patients and 18 normotensive controls. 11 beta-HSD2 enzyme activity was estimated by the F/E ratio, the activity of 11 beta-HSD1 in compare to 11 beta-HSD2 was inferred by the (5 alpha THF + 5 beta THF)/THE ratio and 5 beta-reductase activity assessed using the E/THE ratio. Activity was considered altered when respective ratios exceeded the maximum value observed in the normotensive controls. A 15.7% of patients presented high F/E ratio suggesting a deficit of 11 beta-HSD2 activity. Of the remaining 86 hypertensive patients, two possessed high (5 alpha THF + 5 beta THF)/THE ratios and 12.8% had high E/THE ratios. We observed a high percentage of alterations in cortisol metabolism at pre-receptor level in hypertensive patients, previously misclassified as essential. 11 beta-HSD2 and 5 beta-reductase decreased activity and imbalance of 11 beta-HSDs should be considered in the future management of hypertensive patients.
- Item11β-hydroxysteroid dehydrogenase type 2 polymorphisms and activity in a Chilean essential hypertensive and normotensive cohort.(2012) Campino, Carmen; Quinteros, Hector; Owen, Gareth I.; Carvajal, Cristian A.; Morales, Mauricio; Olivieri, Oliviero; Guidi, Giancesare; Faccini, Giovanni; Pasini, Francesco; Baudrand, Rene; Padilla, Oslando; Valdivia, Carolina; Thichauer, Juan; Lagos, Carlos F.; Kalergis, Alexis M.; Fardella, Carlos E.BACKGROUND: 11β-hydroxysteroid dehydrogenase type 2 enzyme (11β-HSD2) inactivates cortisol (F) to cortisone (E); its impairment is associated with hypertension. We reported that 15.7% of the Chilean essential hypertensives possessed a high F/E ratio suggesting a partial deficit in 11β-HSD2 activity. It has been reported that the G534A(Glu178/Glu) polymorphism in the HSD11B2 gene is associated with hypertension. Investigate the frequency of the G534A polymorphism and its correlation with the glucocorticoid profile in Chilean essential hypertensive and normotensive subjects. METHODS: Essential hypertensive outpatients (n = 232) and normotensive subjects (n = 74) were recruited. A change in the AluI restriction enzyme digest pattern, caused by the presence of the G534A polymorphism, was utilized to screen DNA isolated from leukocytes within the cohort before confirmation by sequencing. Plasma renin activity (PRA), serum aldosterone, F, and E were measured by radioimmunoassay. Urinary tetrahydrocortisol (THF), 5α-tetrahydrocortisol (5α-THF), and tetrahydrocortisone (THE) were measured by gas chromatography-mass spectrometry. RESULTS: G534A polymorphism frequency was similar between hypertensive patients (19 of 232; 8.2%) and normotensive subjects (7 of 74; 9.5%). When categorized by presence or absence of the G534A polymorphism, no significant differences in the serum F/E ratio or other measured biochemical variables were detected. Despite a previous report that the G534A polymorphism is associated with a neighboring C468A (Thr156/Thr) polymorphism, analysis within our cohort showed that only one patient in each group presented with this double polymorphism. CONCLUSIONS: We report the frequency of the G534A polymorphism in the Spanish-Amerindian population. No correlation was detected between this polymorphism and the presence of hypertension and biochemical parameters in this Chilean cohort.
- ItemCitosine-Adenine-Repeat Microsatellite of 11 beta-hydroxysteroid dehydrogenase 2 Gene in Hypertensive Children(OXFORD UNIV PRESS, 2016) Valdivia, Carolina; Carvajal, Cristian A.; Campino, Carmen; Allende, Fidel; Martinez Aguayo, Alejandro; Baudrand, Rene; Vecchiola, Andrea; Lagos, Carlos F.; Tapia Castillo, Alejandra; Fuentes, Cristobal A.; Aglony, Marlene; Solari, Sandra; Kalergis, Alexis M.; Garcia, Hernan; Owen, Gareth I.; Fardella, Carlos E.BACKGROUND
- ItemCoagulation Factor Xa Promotes Solid Tumor Growth, Experimental Metastasis and Endothelial Cell Activation.(2019) Arce, Maximiliano; Pinto, Mauricio P.; Galleguillos, Macarena; Muñoz, Catalina; Lange, Soledad; Ramirez, Carolina; Erices, Rafaela; Gonzalez, Pamela; Velasquez, Ethel; Tempio, Fabián; Lopez, Mercedes N.; Salazar-Onfray, Flavio; Cautivo, Kelly; Kalergis, Alexis M.; Cruz, Sebastián; Lladser, Álvaro; Lobos-González, Lorena; Valenzuela, Guillermo; Olivares, Nixa; Sáez, Claudia; Koning, Tania; Sánchez, Fabiola A.; Fuenzalida, Patricia; Godoy, Alejandro; Contreras Orellana, Pamela; Leyton, Lisette; Lugano, Roberta; Dimberg, Anna; Quest, Andrew F.G.; Owen, Gareth I.Hypercoagulable state is linked to cancer progression; however, the precise role of the coagulation cascade is poorly described. Herein, we examined the contribution of a hypercoagulative state through the administration of intravenous Coagulation Factor Xa (FXa), on the growth of solid human tumors and the experimental metastasis of the B16F10 melanoma in mouse models. FXa increased solid tumor volume and lung, liver, kidney and lymph node metastasis of tail-vein injected B16F10 cells. Concentrating on the metastasis model, upon coadministration of the anticoagulant Dalteparin, lung metastasis was significantly reduced, and no metastasis was observed in other organs. FXa did not directly alter proliferation, migration or invasion of cancer cells in vitro. Alternatively, FXa upon endothelial cells promoted cytoskeleton contraction, disrupted membrane VE-Cadherin pattern, heightened endothelial-hyperpermeability, increased inflammatory adhesion molecules and enhanced B16F10 adhesion under flow conditions. Microarray analysis of endothelial cells treated with FXa demonstrated elevated expression of inflammatory transcripts. Accordingly, FXa treatment increased immune cell infiltration in mouse lungs, an effect reduced by dalteparin. Taken together, our results suggest that FXa increases B16F10 metastasis via endothelial cell activation and enhanced cancer cell-endothelium adhesion advocating that the coagulation system is not merely a bystander in the process of cancer metastasis.
- ItemIncreased urinary glucocorticoid metabolites are associated with metabolic syndrome, hypoadiponectinemia, insulin resistance and beta cell dysfunction(ELSEVIER SCIENCE INC, 2011) Baudrand, Rene; Campino, Carmen; Carvajal, Cristian A.; Olivieri, Oliviero; Guidi, Giancesare; Faccini, Giovanni; Sateler, Javiera; Cornejo, Javiera; San Martin, Betty; Dominguez, Jose M.; Cerda, Jaime; Mosso, Lorena M.; Owen, Gareth I.; Kalergis, Alexis M.; Fardella, Carlos E.Metabolic syndrome (MetS) may have increased cortisol (F) production caused by 11 beta-hydroxysteroid dehydrogenase 1 (11 beta-HSD1) in liver and adipose tissue and/or by HPA axis dysregulation. F is then mainly metabolized by liver reductases into inactive tetrahydrometabolites (THMs). We measured THM levels in patients with or without MetS and evaluate the correlation between THMs and anthropometric and biochemical parameters. We recruited 221 subjects, of whom 130 had MetS by ATP III. We evaluated F, cortisone (E), adipokines, glucose, insulin and lipid profiles as well as urinary (24 h) F. E and THM levels. beta Cell function was estimated by the HOMA Calculator. We observed that patients with MetS showed higher levels of THMs, HOMA-IR and leptin and lower levels of adiponectin and HOMA-beta but no differences in F and E in plasma or urine. THM was associated with weight (r = +0.44, p < 0,001), waist circumference (r = +0.38, p < 0.01). glycemia (r = +0.37, p < 0.01), and triglycerides (r = +0.18, p = 0.06) and negatively correlated with adiponectin (r = -0.36, p < 0.001), HOMA-beta (r = -0.21, p < 0.001) and HDL (r = -0.29, p < 0.01). In a logistic regression model, THM levels were associated with hypertension, hyperglycemia and dyslipidemia. We conclude that MetS is associated with increased urinary THMs but not with F and E levels in plasma or urine. Increased levels of THM, reflecting the daily cortisol production subsequently metabolized, are correlated with hypoadiponectinemia, hypertension, dyslipidemia, insulin resistance and beta cell dysfunction. A subtle increased in glucocorticoid production may further account for the phenotypic and biochemical similarities observed in central obesity and Cushing's syndrome. (C) 2011 Elsevier Inc. All rights reserved.
- ItemPPAR alpha and PPAR gamma regulate the nucleoside transporter hENT1(ACADEMIC PRESS INC ELSEVIER SCIENCE, 2012) Montero, Trinidad D.; Racordon, Dusan; Bravo, Loreto; Owen, Gareth I.; Bronfman, Miguel L.; Leisewitz, Andrea V.Human equilibrative nucleoside transporter 1 (hENT1) is an important determinant for nucleoside analog based chemotherapy success. Preliminary data suggest hENT1 regulation by PPARs. Using A2780 cells, we investigated the role of PPARs on hENT1 expression and activity.
- ItemProgesterone promotes focal adhesion formation and migration in breast cancer cells through induction of protease-activated receptor-1(BIOSCIENTIFICA LTD, 2012) Diaz, Jorge; Aranda, Evelyn; Henriquez, Soledad; Quezada, Marisol; Espinoza, Estefania; Loreto Bravo, Maria; Oliva, Barbara; Lange, Soledad; Villalon, Manuel; Jones, Marius; Brosens, Jan J.; Kato, Sumie; Cuello, Mauricio A.; Knutson, Todd P.; Lange, Carol A.; Leyton, Lisette; Owen, Gareth I.Progesterone and progestins have been demonstrated to enhance breast cancer cell migration, although the mechanisms are still not fully understood. The protease-activated receptors (PARs) are a family of membrane receptors that are activated by serine proteases in the blood coagulation cascade. PAR1 (F2R) has been reported to be involved in cancer cell migration and overexpressed in breast cancer. We herein demonstrate that PAR1 mRNA and protein are upregulated by progesterone treatment of the breast cancer cell lines ZR-75 and T47D. This regulation is dependent on the progesterone receptor (PR) but does not require PR phosphorylation at serine 294 or the PR proline-rich region mPRO. The increase in PAR1 mRNA was transient, being present at 3 h and returning to basal levels at 18 h. The addition of a PAR1-activating peptide (aPAR1) to cells treated with progesterone resulted in an increase in focal adhesion (FA) formation as measured by the cellular levels of phosphorylated FA kinase. The combined but not individual treatment of progesterone and aPAR1 also markedly increased stress fiber formation and the migratory capacity of breast cancer cells. In agreement with in vitro findings, data mining from the Oncomine platform revealed that PAR1 expression was significantly upregulated in PR-positive breast tumors. Our observation that PAR1 expression and signal transduction are modulated by progesterone provides new insight into how the progestin component in hormone therapies increases the risk of breast cancer in postmenopausal women. Journal of Endocrinology (2012) 214, 165-175
- ItemProgesterone Utilizes Distinct Membrane Pools of Tissue Factor to Increase Coagulation and Invasion and These Effects are Inhibited by TFPI(WILEY, 2011) Henriquez, Soledad; Calderon, Claudia; Quezada, Marisol; Oliva, Barbara; Loreto Bravo, Maria; Aranda, Evelyn; Kato, Sumie; Cuello, Mauricio A.; Gutierrez, Jorge; Quest, Andrew F. G.; Owen, Gareth I.Tissue factor (TF) serving as the receptor for coagulation factor VII (FVII) initiates the extrinsic coagulation pathway. We previously demonstrated that progesterone increases TF, coagulation and invasion in breast cancer cell lines. Herein, we investigated if tissue factor pathway inhibitor (TFPI) could down-regulate progesterone-increased TF activity in these cells. Classically, TFPI redistributes TF-FVII-FX-TFPI in an inactive quaternary complex to membrane associated lipid raft regions. Herein, we demonstrate that TF increased by progesterone is localized to the heavy membrane fraction, despite progesterone-increased coagulation originating almost exclusively from lipid raft domains, where TF levels are extremely low. The progesterone increase in coagulation is not a rapid effect, but is progesterone receptor (PR) dependent and requires protein synthesis. Although a partial relocalization of TF occurs, TFPI does not require the redistribution to lipid rafts to inhibit coagulation or invasion. Inhibition by TFPI and anti-TF antibodies in lipid raft membrane fractions confirmed the dependence on TF for progesterone-mediated coagulation. Through the use of pathway inhibitors, we further demonstrate that the TF up-regulated by progesterone is not coupled to the progesterone increase in TF-mediated coagulation. However, the progesterone up-regulated TF protein may be involved in progesterone-mediated breast cancer cell invasion, which TFPI also inhibits. J. Cell. Physiol. 226: 3278-3285, 2011. (C) 2011 Wiley Periodicals, Inc.
- ItemThe oestrogen metabolite 2-methoxyoestradiol alone or in combination with tumour necrosis factor-related apoptosis-inducing ligand mediates apoptosis in cancerous but not healthy cells of the human endometrium(BIOSCIENTIFICA LTD, 2007) Kato, Sumie; Sadarangani, Anil; Lange, Soledad; Villalon, Manuel; Branes, Jorge; Brosens, Jan J.; Owen, Gareth I.; Cuello, MauricioCancers of the reproductive tract account for 12% of all malignancies in women. As previous studies have shown that oestrogen metabolites can cause apoptosis, we characterised the effect of oestrogen and oestrogen metabolites on non-cancerous and cancerous human endometrial cells. Herein, we demonstrate that 2-methoxyoestradiol (2ME), but not 17 beta-oestradiol, induces apoptosis in cancer cell lines and primary cultured tumours; of endometrial origin. In contrast, 2ME had no effect on cell viability of corresponding normal tissue. This ability of 2ME to induce apoptosis does not require oestrogen receptor activation, but is associated with increased entry into the G2/M phases of the cell cycle and the activation of both the intrinsic and the extrinsic apoptotic pathways. The selective behaviour of 2ME on cancerous as opposed to normal tissue may be due to a reduction in 17 beta -hydroxysteroid dehydrogenase type 11 levels in cancer cells and to a differential down-regulation of superoxide dismutase. Furthermore, we demonstrate that pre-treatment with 2ME enhances the sensitivity of reproductive tract cancer cells to the apoptotic drug tumour necrosis factor-related apoptosis-inducing ligand (TRAIL), without the loss in cell viability to normal cells incurred by currently chemotherapeutic drugs. In conclusion, 2ME, alone or in combination with TRAIL, may be an effective treatment for cancers of uterine origin with minimal toxicity to corresponding healthy female reproductive tissue.
- ItemTRAIL mediates apoptosis in cancerous but not normal primary cultured cells of the human reproductive tract (vol 12, pg 73, 2007)(SPRINGER, 2007) Sadarangani, Anil; Kato, Sumie; Espinoza, Natalia; Lange, Soledad; Llados, Carmen; Espinosa, Marisol; Villalon, Manuel; Lipkowitz, Stanley; Cuello, Mauricio; Owen, Gareth I.