The impact of the micronutrient iodine in health and diseases.

Adequate iodine nutrition is crucial for all mammals by playing his starring role as a component of thyroid hormones, which are key regulators of cellular processes for life such as differentiation, growth, function, and metabolism. Deficiency or excess of iodine in the diet are worldwide highly frequent conditions that are responsible of health problems like hypothyroidism, hypothyroxinemia, goiter, thyroiditis, hyperthyroidism, and autoimmune thyroid diseases among others. The incorporation of iodine in salt or other nutrients resolved the consequences of severe iodine deficiency like goiter, cretinism. However, this strategy in several countries led to other ailments like Hashimoto autoimmune thyroiditis, hyperthyroidism, and hypothyroidism. The goal of this review is to analyze and discuss the different aspects of iodine nutrition for human health comprising its biological role through thyroid hormones, pathogen control, and the regulation of the intestinal microbiota.

[Testosterone inhibits human wild-type and chimeric aldosterone synthase activity in vitro]. / Testosterona inhibe la actividad de la aldosterona sintasa silvestre y quimérica in vitro.

BACKGROUND: Familial hyperaldosteronism type I is caused by the generation of a chimeric aldosterone synthase enzyme (ASCE) which is regulated by ACTH instead of angiotensin II. We have reported that in vitro, the wild-type (ASWT) and chimeric aldosterone synthase (ASCE) enzymes are inhibited by progesterone and estradiol does not affect their activity. AIM: To explore the direct action of testosterone on ASWT and ASCE enzymes. MATERIAL AND METHODS: HEK-293 cells were transiently transfected with vectors containing the full ASWT or ASCE cDNAs. The effect of testosterone on AS enzyme activities was evaluated incubating HEK-cells transfected with enzyme vectors and adding deoxycorticosterone (DOC) alone or DOC plus increasing doses of testosterone. Aldosterone production was measured by HPLC-MS/MS. Docking of testosterone within the active sites of both enzymes was performed by modelling in silico. RESULTS: In this system, testosterone inhibited ASWT (90% inhibition at five pM, 50% inhibitory concentration (IC50) =1.690 pM) with higher efficacy andpotency than ASCE (80% inhibition at five pM, IC50=3.176 pM). Molecular modelling studies showed different orientation of testosterone in ASWT and ASCE crystal structures. CONCLUSIONS: The inhibitory effect of testosterone on ASWT or ASCE enzymes is a novel non-genomic testosterone action, suggesting that further clinical studies are needed to assess the role of testosterone in the screening and diagnosis of primary aldosteronism.

Downregulation of exosomal miR-192-5p and miR-204-5p in subjects with nonclassic apparent mineralocorticoid excess.

BACKGROUND: The "nonclassic" apparent mineralocorticoid excess (NC-AME) has been identified in approximately 7% of general population. This phenotype is characterized by low plasma renin activity (PRA), high serum cortisol (F) to cortisone (E) ratio, low cortisone, high Fractional Excretion of potassium (FEK) and normal-elevated systolic blood pressure (SBP). An early detection and/or identification of novel biomarkers of this phenotype could avoid the progression or future complications leading to arterial hypertension. Isolation of extracellular vesicles, such as exosomes, in specific biofluids support the identification of tissue-specific RNA and miRNA, which may be useful as novel biomarkers. Our aim was to identify miRNAs within urinary exosomes associated to the NC-AME phenotype. METHODS: We perform a cross-sectional study in a primary care cohort of 127 Chilean subjects. We measured BP, serum cortisol, cortisone, aldosterone, PRA. According to the previous reported, a subgroup of subjects was classified as NC-AME (n = 10). Urinary exosomes were isolated and miRNA cargo was sequenced by Illumina-NextSeq-500. RESULTS: We found that NC-AME subjects had lower cortisone (p < 0.0001), higher F/E ratio (p < 0.0001), lower serum potassium (p = 0.009) and higher FEK 24 h (p = 0.03) than controls. We found miR-204-5p (fold-change = 0.115; p 0.001) and miR-192-5p (fold-change = 0.246; p 0.03) are both significantly downregulated in NC-AME. miR-192-5p expression was correlated with PRA (r = 0.45; p 0.028) and miR-204-5p expression with SBP (r = - 0.48, p 0.027) and F/E ratio (r = - 0.48; p 0.026). CONCLUSIONS: These findings could support a potential role of these miRNAs as regulators and novel biomarkers of the NC-AME phenotype.

[Update in the clinical management of low renin hypertension]. / Actualización en el manejo clínico de la hipertensión hiporreninémica.

The renin-angiotensin-aldosterone system modulates volume, sodium and potassium homeostasis. In the setting of a high sodium diet, up to 30% of patients with hypertension have a low or suppressed renin and increased volume. This phenotype of low renin hypertension (LRH) is multifactorial and includes infrequent inherited genetic syndromes, milder phenotypes of classic diseases and environmental exposures. All these conditions have in common a higher cardiovascular risk mediated by the over activation of the mineralocorticoid receptor (MR), present not only in the kidney, but also in vasculature, myocardium and adipocytes. Consequently, the aim of LRH treatment goes beyond the control of blood pressure and requires antagonizing MR with specific pharmacologic agents, pursuing normalization of renin as a clinical objective. Due to the unusual evaluation of renin status by non-endocrinologists and lack of disease awareness, only a minority of hypertensive patients receive this pathophysiologically-driven treatment that should reduce cardiovascular outcomes.

Depressive symptoms are associated with higher morning plasma cortisol in primary care subjects.

BACKGROUND: Cortisol dysregulation has a potential role in depression. AIM AND METHODS: We evaluated depressive symptoms using the Hamilton Rating Scale for Depression in 48 primary care subjects without history of previous or current depression and its association with cortisol dysregulation (morning plasma cortisol, 24-hour urinary free cortisol and cortisol metabolites). Presence of metabolic syndrome and inflammatory parameters were also assessed. RESULTS: Hamilton Rating Scale for Depression correlated significantly with morning cortisol, but not with urinary free cortisol or metabolites. A significant increase in morning cortisol by Hamilton groups (asymptomatic ≤8; mild to moderate: 9-18; moderate to severe: ≥19) was observed even when adjusted by age/gender. We observed no association of depressive symptoms with metabolic or inflammatory parameters. CONCLUSION: Depressive symptoms in primary care subjects not consulting for their mood are associated with higher morning plasma cortisol, but not urinary cortisol or its metabolites. These observations suggest that systemic hypercortisolism and related metabolic disorders are not observed in mild/initial states of depressive disorders.

Aldosterone Production and Signaling Dysregulation in Obesity.

In the past decades, we have extended the view of aldosterone effects beyond epithelial tissues. New evidence regarding the aldosterone/mineralocorticoid receptor (MR) pathway in active metabolic tissues, including adipose tissue, has confirmed its pathogenic role in systemic inflammation, endothelial dysfunction, insulin resistance, and dyslipidemia. Obesity, a current epidemic worldwide, increases aldosterone production by several adipocyte factors such as leptin but is also associated with local aldosterone production. In addition, obesity can modulate MR activation leading to signaling dysregulation and a pro-inflammatory profile of adipocytes. Current knowledge have deciphered that this phenotypical differences of obesity may be explained, at least in part, by novel non-genomic activation of MR, new inducers of aldosterone synthesis, and probably by several epigenetic modifications. In addition, with the understanding of the complex interplay of obesity, hormones, and receptors, targeted pharmacological therapy is expected and is currently under active research.

Role of the Renin-Angiotensin-Aldosterone System beyond Blood Pressure Regulation: Molecular and Cellular Mechanisms Involved in End-Organ Damage during Arterial Hypertension.

Arterial hypertension is a common condition worldwide and an important predictor of several complicated diseases. Arterial hypertension can be triggered by many factors, including physiological, genetic, and lifestyle causes. Specifically, molecules of the renin-angiotensin-aldosterone system not only play important roles in the control of blood pressure, but they are also associated with the genesis of arterial hypertension, thus constituting a need for pharmacological interventions. Chronic high pressure generates mechanical damage along the vascular system, heart, and kidneys, which are the principal organs affected in this condition. In addition to mechanical stress, hypertension-induced oxidative stress, chronic inflammation, and the activation of reparative mechanisms lead to end-organ damage, mainly due to fibrosis. Clinical trials have demonstrated that renin-angiotensin-aldosterone system intervention in hypertensive patients lowers morbidity/mortality and inflammatory marker levels as compared to placebo patients, evidencing that this system controls more than blood pressure. This review emphasizes the detrimental effects that a renin-angiotensin-aldosterone system (RAAS) imbalance has on health considerations above and beyond high blood pressure, such as fibrotic end-organ damage.

Beneficial effects of mineralocorticoid receptor blockade in experimental non-alcoholic steatohepatitis.

BACKGROUND: Therapeutic options to treat Non-alcoholic steatohepatitis (NASH) are limited. Mineralocorticoid receptor (MR) activation could play a role in hepatic fibrogenesis and its modulation could be beneficial for NASH. AIM: To investigate whether eplerenone, a specific MR antagonist, ameliorates liver damage in experimental NASH. METHODS: C57bl6 mice were fed a choline-deficient and amino acid-defined (CDAA) diet for 22 weeks with or without eplerenone supplementation. Serum levels of aminotransferases and aldosterone were measured and hepatic steatosis, inflammation and fibrosis scored histologically. Hepatic triglyceride content (HTC) and hepatic mRNA levels of pro-inflammatory pro-fibrotic, oxidative stress-associated genes and of MR were also assessed. RESULTS: CDAA diet effectively induced fibrotic NASH, and increased the hepatic expression of pro-inflammatory, pro-fibrotic and oxidative stress-associated genes. Hepatic MR mRNA levels significantly correlated with the expression of pro-inflammatory and pro-fibrotic genes and were significantly increased in hepatic stellate cells obtained from CDAA-fed animals. Eplerenone administration was associated to a reduction in histological steatosis and attenuation of liver fibrosis development, which was associated to a significant decrease in the expression of collagen-α1, collagen type III, alpha 1 and Matrix metalloproteinase-2. CONCLUSION: The expression of MR correlates with inflammation and fibrosis development in experimental NASH. Specific MR blockade with eplerenone has hepatic anti-steatotic and anti-fibrotic effects. These data identify eplerenone as a potential novel therapy for NASH. Considering its safety and FDA-approved status, human studies are warranted.

LC-MS/MS Method for the Simultaneous Determination of Free Urinary Steroids.

Cortisol homeostasis is implicated in hypertension and metabolic syndrome. Two enzymes modulate cortisol availability; 11ß-hydroxysteroid dehydrogenase type 1 (11ß-HSD1) preferentially converts inactive cortisone to cortisol, whereas 11ß-hydroxysteroid dehydrogenase type 2 (11ß-HSD2) converts cortisol to cortisone. In contrast, 5α and 5ß reductases inactivate cortisol by conversion to its tetrahydrometabolites: tetrahydrocortisol, allo-tetrahydrocortisol and tetrahydrocortisone. A subtle local increase in cortisol can be detected by measuring 24-h urine metabolites, LC-MS/MS being the reference method. The 11ß-HSD2 activity is assessed based on the cortisol/cortisone ratio, and the 11ß-HSD1 activity on the (tetrahydrocortisol + allo-tetrahydrocortisol)/tetrahydrocortisone ratio. To better understand hypertension and/or metabolic syndrome pathogenesis a method for simultaneous determination of cortisol, cortisone, tetrahydrocortisol, allo-tetrahydrocortisol and tetrahydrocortisone was developed and validated in an LC coupled with the new detector AB Sciex QTrap® 4500 tandem mass spectrometer. The steroids were extracted from 1 mL urine, using cortisol-D4 as internal standard. The quantification range was 0.1-120 ng/mL for cortisol and cortisone, and 1-120 ng/mL for tetrahydrometabolites, with >89 % recovery for all analytes. The coefficient of variation and accuracy was <10 %, and 85-105 %, respectively. Our LC-MS/MS method is accurate and reproducible in accordance with Food and Drug Administration guidelines, showing good sensitivity and recovery. This method allows the assessment of 11ß-HSD2 and 11ß-HSD1 activities in a single analytical run providing an innovative tool to explain etiology of misclassified essential hypertension and/or metabolic syndrome.

Familial hyperaldosteronism: an European Reference Network on Rare Endocrine Conditions clinical practice guideline.

We describe herein the European Reference Network on Rare Endocrine Conditions clinical practice guideline on diagnosis and management of familial forms of hyperaldosteronism. The guideline panel consisted of 10 experts in primary aldosteronism, endocrine hypertension, paediatric endocrinology, and cardiology as well as a methodologist. A systematic literature search was conducted, and because of the rarity of the condition, most recommendations were based on expert opinion and small patient series. The guideline includes a brief description of the genetics and molecular pathophysiology associated with each condition, the patients to be screened, and how to screen. Diagnostic and treatment approaches for patients with genetically determined diagnosis are presented. The recommendations apply to patients with genetically proven familial hyperaldosteronism and not to families with more than one case of primary aldosteronism without demonstration of a responsible pathogenic variant.

The role of sex hormones in aldosterone biosynthesis and their potential impact on its mineralocorticoid receptor.

Blood pressure (BP) regulation is a complex process involving various hormones, including aldosterone and its mineralocorticoid receptor. Mineralocorticoid receptor is expressed in several tissues, including the kidney, and plays a crucial role in regulating BP by controlling the sodium and water balance. During different stages of life, hormonal changes can affect mineralocorticoid receptor activity and aldosterone levels, leading to changes in BP. Increasing evidence suggests that sex steroids modulate aldosterone levels. Estrogens, particularly estradiol, mediate aldosterone biosynthesis by activating classical estrogen receptors and the G protein-coupled receptor. Progesterone acts as an anti-mineralocorticoid by inhibiting the binding of aldosterone to the mineralocorticoid receptor. Moreover, progesterone inhibits aldosterone synthase enzymes. The effect of testosterone on aldosterone synthesis is still a subject of debate. However, certain studies show that testosterone downregulates the mRNA levels of aldosterone synthase, leading to decreased plasma aldosterone levels.

Adipose Tissue Dysfunction and the Role of Adipocyte-Derived Extracellular Vesicles in Obesity and Metabolic Syndrome.

Obesity is a major public health issue that is associated with metabolic diseases including diabetes mellitus type 2 and metabolic syndrome. This pathology leads to detrimental cardiovascular health and secondary effects, such as lipotoxicity, inflammation, and oxidative stress. Recently, extracellular vesicles (EVs) have been highlighted as novel players participating in human physiology and pathophysiology. In obesity, adipose tissue is related to the active shedding of adipocyte-derived extracellular vesicles (AdEVs). The current review explores and highlights the role of AdEVs and their cargo in obesity and metabolic syndrome. AdEVs are proposed to play an important role in obesity and its comorbidities. AdEVs are biological nanoparticles mainly shed by visceral and subcutaneous adipose tissue, acting in physiological and pathophysiological conditions, and also carrying different cargo biomolecules, such as RNA, microRNA (miRNA), proteins, and lipids, among others. RNA and miRNA have local and systemic effects affecting gene expression in target cell types via paracrine and endocrine actions. State of the art analyses identified some miRNAs, such as miR-222, miR-23b, miR-4429, miR-148b, and miR-4269, that could potentially affect cell pathways involved in obesity-related comorbidities, such as chronic inflammation and fibrosis. Similarly, AdEVs-proteins (RBP4, perilipin-A, FABP, mimecan, TGFBI) and AdEVs-lipids (sphingolipids) have been linked to the obesity pathophysiology. The current knowledge about AdEVs along with further research would support and reveal novel pathways, potential biomarkers, and therapeutic options in obesity.

Low Cortisone as a Novel Predictor of the Low-Renin Phenotype.

A large proportion of patients with low-renin hypertension (LRH) correspond to primary aldosteronism (PA). However, some of these subjects have low to normal aldosterone. Since low renin is driven by excessive mineralocorticoids or glucocorticoids acting on mineralocorticoid receptors (MRs), we hypothesize that a low-cortisone condition, associated classically with 11ßHSD2 deficiency, is a proxy of chronic MR activation by cortisol, which can also lead to low renin, elevated blood pressure, and renal and vascular alterations. Objective: To evaluate low cortisone as a predictor of low renin activity and its association with parameters of kidney and vascular damage. Methods: A cross-sectional study was carried out in 206 adult subjects. The subjects were classified according to low plasma renin activity (<1 ng/mL × hours) and low cortisone (<25th percentile). Results: Plasma renin activity was associated with aldosterone (r = 0.36; P < .001) and cortisone (r = 0.22; P = .001). A binary logistic regression analysis showed that serum cortisone per ug/dL increase predicted the low-renin phenotype (OR 0.4, 95% CI 0.21-0.78). The receiver operating characteristic curves for cortisone showed an area under the curve of 0.6 to discriminate subjects with low renin activity from controls. The low-cortisone subjects showed higher albuminuria and PAI-1 and lower sodium excretion. The association study also showed that urinary cortisone was correlated with blood pressure and serum potassium (P < .05). Conclusion: This is the first study showing that low cortisone is a predictor of a low-renin condition. Low cortisone also predicted surrogate markers of vascular and renal damage. Since the aldosterone to renin ratio is used in the screening of PA, low cortisone values should be considered additionally to avoid false positives in the aldosterone-renin ratio calculation.

Positive association between aldosterone-renin ratio and carotid intima-media thickness in hypertensive children.

INTRODUCTION: From an early age, hypertension can damage blood vessels through multiple mechanisms. The aim of this study was to evaluate the presence of vascular damage and whether it is associated with the mineralo- and glucocorticoid profiles of hypertensive children. SUBJECTS AND METHODS: We studied 64 hypertensive children. Anthropometric parameters and serum aldosterone (SA), plasma renin activity (PRA), aldosterone/renin ratio (ARR), cortisol (F) and cortisone (E) were measured. The serum F/E ratio was calculated to estimate the activity of the enzyme 11ß-HSD2. Vascular damage was determined by carotid intima-media thickness (cIMT) and flow-mediated dilation of the brachial artery (FMD) on ultrasound. RESULTS: (median; Q1-Q3) Of the patients observed, 39% were females, and the median value for age (years) was 11.2 (9.1-13.3), for BMI (SDS) was 1.36 (0.84-1.80), for body fat mass (%) was 28.3 (17.8-36.0), for SBP index was 1.17 (1.12-1.25) and for the DBP index was 1.27 (1.16-1.36). Measurements revealed an SA level higher than 491 pmol/l in 4/64 patients, a PRA value lower than 0.5 ng/ml/h in 2/64, an ARR higher than 10 in 3/64 and serum F/E ratio higher than 4.3 in 10/64. The median brachial FMD (%) was 8.41 (5.61-10.91), and the median cIMT (mm) was 0.40 (0.37-0.43). The ARR was the only variable that explained changes in cIMT (ß = 0.571, R(2 ) = 0.315, P < 0.0001). CONCLUSION: Our results showed a positive association between cIMT and the ARR, suggesting an important role of the renin-aldosterone axis in the regulation of early vascular damage in hypertensive children.

Different effects of progesterone and estradiol on chimeric and wild type aldosterone synthase in vitro.

BACKGROUND: Familial hyperaldosteronism type I (FH-I) is caused by the unequal recombination between the 11beta-hydroxylase (CYP11B1) and aldosterone synthase (CYP11B2) genes, resulting in the generation of a CYP11B1/B2 chimeric gene and abnormal adrenal aldosterone production. Affected patients usually show severe hypertension and an elevated frequency of stroke at a young age. Aldosterone levels rise during pregnancy, yet in pregnant women with FH-1, their hypertensive condition either remains unchanged or may even improve. The purpose of this study was to investigate in vitro whether female sex steroids modulate the activity of chimeric (ASCE) or wild type (ASWT) aldosterone synthase enzymes. METHODS: We designed an in vitro assay using HEK-293 cell line transiently transfected with vectors containing the full ASCE or ASWT cDNAs. Progesterone or estradiol effects on AS enzyme activities were evaluated in transfected cells incubated with deoxycorticosterone (DOC) alone or DOC plus increasing doses of these steroids. RESULTS: In our in vitro model, both enzymes showed similar apparent kinetic parameters (Km = 1.191 microM and Vmax = 27.08 microM/24 h for ASCE and Km = 1.163 microM and Vmax = 36.98 microM/24 h for ASWT; p = ns, Mann-Whitney test). Progesterone inhibited aldosterone production by ASCE- and ASWT-transfected cells, while estradiol demonstrated no effect. Progesterone acted as a competitive inhibitor for both enzymes. Molecular modelling studies and binding affinity estimations indicate that progesterone might bind to the substrate site in both ASCE and ASWT, supporting the idea that this steroid could regulate these enzymatic activities and contribute to the decay of aldosterone synthase activity in chimeric gene-positive patients. CONCLUSIONS: Our results show an inhibitory action of progesterone in the aldosterone synthesis by chimeric or wild type aldosterone synthase enzymes. This is a novel regulatory mechanism of progesterone action, which could be involved in protecting pregnant women with FH-1 against hypertension. In vitro, both enzymes showed comparable kinetic parameters, but ASWT was more strongly inhibited than ASCE. This study implicates a new role for progesterone in the regulation of aldosterone levels that could contribute, along with other factors, to the maintenance of an adequate aldosterone-progesterone balance in pregnancy.

ThyroidPrint®: clinical utility for indeterminate thyroid cytology.

Molecular testing contributes to improving the diagnosis of indeterminate thyroid nodules (ITNs). ThyroidPrint® is a ten-gene classifier aimed to rule out malignancy in ITN. Post-validation studies are necessary to determine the real-world clinical benefit of ThyroidPrint® in patients with ITN. A single-center, prospective, noninterventional clinical utility study was performed, analyzing the impact of ThyroidPrint® in the physicians' clinical decisions for ITN. Demographics, nodule characteristics, benign call rates (BCRs), and surgical outcomes were measured. Histopathological data were collected from surgical biopsies of resected nodules. Of 1272 fine-needle aspirations, 109 (8.6%) were Bethesda III and 135 (10.6%) were Bethesda IV. Molecular testing was performed in 155 of 244 ITN (63.5%), of which 104 were classified as benign (BCR of 67.1%). After a median follow-up of 15 months, 103 of 104 (99.0%) patients with a benign ThyroidPrint® remained under surveillance and one patient underwent surgery which was a follicular adenoma. Surgery was performed in all 51 patients with a suspicious for malignancy as per ThyroidPrint® result and in 56 patients who did not undergo testing, with a rate of malignancy of 70.6% and 32.1%, respectively. A higher BCR was observed in follicular lesion of undetermined significance (87%) compared to atypia of undetermined significance (58%) (P < 0.05). False-positive cases included four benign follicular nodules and six follicular and four oncocytic adenomas. Our results show that, physicians chose active surveillance instead of diagnostic surgery in all patients with a benign ThyroidPrint® result, reducing the need for diagnostic surgery in 67% of patients with preoperative diagnosis of ITN.

Birth weight is inversely associated with blood pressure and serum aldosterone and cortisol levels in children.

CONTEXT: Low birth weight has been independently associated with adult hypertension, and renin-angiotensin system (RAS) plays a role in this connection. OBJECTIVE: To characterize the associations between birth weight (BW) and serum aldosterone (SA), serum cortisol, plasma renin activity (PRA) and blood pressure (BP). DESIGN: Cross-sectional study. SUBJECTS: Children from the community born at a gestational age >32 weeks. METHODS: Systolic and diastolic BP indices (SBPi and DBPi) were calculated using the observed BP/50th percentile BP for gender, age and stature. BW was transformed to a standard deviation score (SDS) for gestational age, whereas SA, serum cortisol and PRA were transformed using the natural log. RESULTS: We selected 288 subjects between the ages of 4·9 and 15·5 years (Females, 50%). After adjusting for body mass index (BMI) SDS and Tanner, multiple regression analysis revealed that BW (SDS) was both independently and inversely associated with the natural log of SA (ß = -0·065; P = 0·039), the natural log of serum cortisol (ß = -0·064; P = 0·009), SBPi (ß = -0·012; P = 0·020) and DBPi (ß = -0·023; P = 0·002). An association was not observed with PRA (P = 0·178) and aldosterone renin ratio (ARR) (P = 0·452). Serum cortisol levels were positively associated with SA (r = 0·125; P = 0·034), while an association with PRA (P = 0·251) and ARR (P = 0·052) was not observed. CONCLUSIONS: The results of this study demonstrate an inverse association between birth weight and blood pressure and serum aldosterone and cortisol levels. This association is independent of BMI and Tanner, suggesting foetal programming of the hypothalamic-pituitary-adrenal axis.

Overexpression of 11ß-hydroxysteroid dehydrogenase type 1 in visceral adipose tissue and portal hypercortisolism in non-alcoholic fatty liver disease.

BACKGROUND: The enzyme 11ß-hydroxysteroid-dehydrogenase type 1 (11ß-HSD1) catalyses the reactivation of intracellular cortisol. We explored the potential role of 11ß-HSD1 overexpression in visceral adipose tissue (VAT) in non-alcoholic fatty liver disease (NAFLD) assessing sequential changes of enzyme expression, in hepatic and adipose tissue, and the occurrence of portal hypercortisolism in obese mice. 11ß-HSD1 expression was also assessed in tissues from obese patients undergoing bariatric surgery. METHODS: Peripheral and portal corticosterone levels and liver histology were assessed in ob/ob mice at two time points (8-12 weeks of age). 11ß-HSD1 tissue expression was assessed in by RT-pcr in ob/ob mice and in 49 morbidly obese patients. RESULTS: Portal corticosterone serum levels were higher in obese mice with a 26% decrease between 8 and 12 weeks of age (controls: 78.3 ± 19.7 ng/ml, 8-week-old ob/ob: 167.5 ± 14.5 ng/ml and 12-week-old ob/ob: 124.3 ± 28 ng/ml, P < 0.05). No significant differences were found in peripheral corticosterone serum levels. Expression of 11ß-HSD1 was lower in the liver [-45% at 8 weeks and -35% at 12-weeks (P = 0.0001)] and highly overexpressed in VAT in obese mice, compared to controls (128-fold higher in 8-week-old ob/ob and 41-fold higher in 12-week-old ob/ob, P < 0.01). No significant differences were seen in the expression of 11ß-HSD1 in subcutaneous adipose tissue. In multivariate analysis, human 11ß-HSD1 expression in VAT (OR: 1.385 ± 1.010-1.910) was associated with NAFLD. CONCLUSION: Murine NAFLD is associated with portal hypercortisolism and11ß-HSD1 overexpression in VAT. In humans, 11ß-HSD1 VAT expression was associated with the presence of NAFLD. Thus, local corticosteroid production in VAT may contribute to NAFLD pathogenesis.

Aldosterone promotes autoimmune damage by enhancing Th17-mediated immunity.

Excessive production of aldosterone leads to the development of hypertension and cardiovascular disease by generating an inflammatory state that can be promoted by T cell immunity. Because nature and intensity of T cell responses is controlled by dendritic cells (DCs), it is important to evaluate whether the function of these cells can be modulated by aldosterone. In this study we show that aldosterone augmented the activation of CD8(+) T cells in a DC-dependent fashion. Consistently, the mineralocorticoid receptor was expressed by DCs, which showed activation of MAPK pathway and secreted IL-6 and TGF-beta in response to aldosterone. In addition, DCs stimulated with aldosterone impose a Th17 phenotype to CD4(+) T cells, which have recently been associated with the promotion of inflammatory and autoimmune diseases. Accordingly, we observed that aldosterone enhances the progression of experimental autoimmune encephalomyelitis, an autoimmune disease promoted by Th17 cells. In addition, blockade of the mineralocorticoid receptor prevented all aldosterone effects on DCs and attenuated experimental autoimmune encephalomyelitis development in aldosterone-treated mice. Our data suggest that modulation of DC function by aldosterone enhances CD8(+) T cell activation and promotes Th17-polarized immune responses, which might contribute to the inflammatory damage leading to hypertension and cardiovascular disease.