Browsing by Author "Guidi, Giancesare"

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    11 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.
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    11β-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.
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    Increased 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.