Omental adipose tissue type 1 11 beta-hydroxysteroid dehydrogenase oxoreductase activity, body fat distribution, and metabolic alterations in women

Adipose tissue in cortisol excess: What Cushing's syndrome can teach us?

Endogenous Cushing's syndrome (CS) is a rare condition due to prolonged exposure to elevated circulating cortisol levels that features its typical phenotype characterised by moon face, proximal myopathy, easy bruising, hirsutism in females and a centripetal distribution of body fat. Given the direct and indirect effects of hypercortisolism, CS is a severe disease burdened by increased cardio-metabolic morbidity and mortality in which visceral adiposity plays a leading role. Although not commonly found in clinical setting, endogenous CS is definitely underestimated leading to delayed diagnosis with consequent increased rate of complications and reduced likelihood of their reversal after disease control. Most of all, CS is a unique model for systemic impairment induced by exogenous glucocorticoid therapy that is commonly prescribed for a number of chronic conditions in a relevant proportion of the worldwide population. In this review we aim to summarise on one side, the mechanisms behind visceral adiposity and lipid metabolism impairment in CS during active disease and after remission and on the other explore the potential role of cortisol in promoting adipose tissue accumulation.

Interplay of Cortisol, Testosterone, and Abdominal Fat Mass in Normal-weight Women With Polycystic Ovary Syndrome

Context

Ovarian and adrenal steroidogenesis underlie endocrine-metabolic dysfunction in polycystic ovary syndrome (PCOS). Adipocytes express aldo-keto reductase 1C3 and type 1 11β-hydroxysteroid dehydrogenase, which modulate peripheral androgen and cortisol production.

Objectives

To compare serum adrenal steroids, including 11-oxygenated androgens (11-oxyandrogens), cortisol, and cortisone between normal-weight women with PCOS and body mass index- and age-matched ovulatory women with normal-androgenic profiles (controls), and assess whether adrenal steroids associate with abdominal adipose deposition.

Design

Prospective, cross-sectional, cohort study.

Setting

Academic medical center.

Patients

Twenty normal-weight women with PCOS and 20 body mass index-/age-matched controls.

Interventions

Blood sampling, IV glucose tolerance testing, and total-body dual-energy x-ray absorptiometry.

Main Outcome Measures

Clinical characteristics, hormonal concentrations, and body fat distribution.

Results

Women with PCOS had higher serum total/free testosterone (T) and androstenedione (A4) levels and a greater android/gynoid fat mass than controls (androgens P < .001; android/gynoid fat mass ratio, P = .026). Serum total/free T and A4 levels correlated positively with android/gynoid fat mass ratio in all women combined (P < .025, all values). Serum 11ß-hydroxyA4, 11-ketoA4, 11ß-hydroxyT, 11-ketoT, cortisol, and cortisone levels were comparable between female types and unrelated to body fat distribution. Serum 11-oxyandrogens correlated negatively with % total body fat, but lost significance adjusting for cortisol. Serum cortisol levels, however, correlated inversely with android fat mass (P = .021), with a trend toward reduced serum cortisol to cortisone ratio in women with PCOS vs controls (P = .075), suggesting diminished 11β-hydroxysteroid dehydrogenase activity.

Conclusion

Reduced cortisol may protect against preferential abdominal fat mass in normal-weight PCOS women with normal serum 11-oxyandrogens.

Experimental drugs for the treatment of idiopathic intracranial hypertension (IIH): shedding light on phase I and II trials

INTRODUCTION

Idiopathic intracranial hypertension is a neurological condition characterized by a raised intracranial pressure and papilledema that causes debilitating headaches. While the extent of the pathophysiology is being discovered, the condition is emerging as a systemic metabolic disease distinct to people living with obesity alone. Idiopathic intracranial hypertension is becoming more common and therefore establishing licensed therapeutics is a key priority.

AREA COVERED

The translation of preclinical work in idiopathic intracranial hypertension is evident by the two early phase trials evaluating 11-β-hydroxysteroid dehydrogenase inhibitor, AZD4017, and a glucagon like peptide-1 receptor agonist, Exenatide. This review summarizes these two early phase trials evaluating targeted medicines for the treatment of intracranial pressure. The modulation of these two distinct mechanisms have potential for therapeutic intervention in people living with idiopathic intracranial hypertension.

EXPERT OPINION

The clinical trial landscape in idiopathic intracranial hypertension is a challenge due to the rarity of the disease and the lack of agreed meaningful trial outcomes. Further preclinical work to fully understand the pathogenesis is required to enable personalized targeted drug treatment.

Ectopic lipid metabolism in anterior pituitary dysfunction

Over the past decades, adapted lifestyle and dietary habits in industrialized countries have led to a progress of obesity and associated metabolic disorders. Concomitant insulin resistance and derangements in lipid metabolism foster the deposition of excess lipids in organs and tissues with limited capacity of physiologic lipid storage. In organs pivotal for systemic metabolic homeostasis, this ectopic lipid content disturbs metabolic action, thereby promotes the progression of metabolic disease, and inherits a risk for cardiometabolic complications. Pituitary hormone syndromes are commonly associated with metabolic diseases. However, the impact on subcutaneous, visceral, and ectopic fat stores between disorders and their underlying hormonal axes is rather different, and the underlying pathophysiological pathways remain largely unknown. Pituitary disorders might influence ectopic lipid deposition indirectly by modulating lipid metabolism and insulin sensitivity, but also directly by organ specific hormonal effects on energy metabolism. In this review, we aim to I) provide information about the impact of pituitary disorders on ectopic fat stores, II) and to present up-to-date knowledge on potential pathophysiological mechanisms of hormone action in ectopic lipid metabolism.

Sexual Dimorphism in Adipose-Hypothalamic Crosstalk and the Contribution of Aryl Hydrocarbon Receptor to Regulate Energy Homeostasis

There are fundamental sex differences in the regulation of energy homeostasis. Better understanding of the underlying mechanisms of energy balance that account for this asymmetry will assist in developing sex-specific therapies for sexually dimorphic diseases such as obesity. Multiple organs, including the hypothalamus and adipose tissue, play vital roles in the regulation of energy homeostasis, which are regulated differently in males and females. Various neuronal populations, particularly within the hypothalamus, such as arcuate nucleus (ARC), can sense nutrient content of the body by the help of peripheral hormones such leptin, derived from adipocytes, to regulate energy homeostasis. This review summarizes how adipose tissue crosstalk with homeostatic network control systems in the brain, which includes energy regulatory regions and the hypothalamic–pituitary axis, contribute to energy regulation in a sex-specific manner. Moreover, development of obesity is contingent upon diet and environmental factors. Substances from diet and environmental contaminants can exert insidious effects on energy metabolism, acting peripherally through the aryl hydrocarbon receptor (AhR). Developmental AhR activation can impart permanent alterations of neuronal development that can manifest a number of sex-specific physiological changes, which sometimes become evident only in adulthood. AhR is currently being investigated as a potential target for treating obesity. The consensus is that impaired function of the receptor protects from obesity in mice. AhR also modulates sex steroid receptors, and hence, one of the objectives of this review is to explain why investigating sex differences while examining this receptor is crucial. Overall, this review summarizes sex differences in the regulation of energy homeostasis imparted by the adipose–hypothalamic axis and examines how this axis can be affected by xenobiotics that signal through AhR.

Adrenal Androgen Predictive Effects on Clinical and Metabolic Abnormalities of Polycystic Ovary Syndrome

OBJECTIVE

 To examine the possible effects of adrenal prohormones in the prediction of clinical and metabolic abnormalities in women with polycystic ovary syndrome (PCOS).

METHODS

 The present study enrolled 299 normal cycling non-PCOS, 156 normoandrogenemic, and 474 hyperandrogenemic women with PCOS. Baseline characteristics were compared using a chi-squared test or analysis of variance (ANOVA) as appropriate. The roles of adrenal prohormones and their ratios with total testosterone in predicting co-occurring morbidities in women PCOS were evaluated using univariate and multivariate logistic regression analyses.

RESULTS

 Adrenal hyperandrogenism per dehydroepiandrosterone sulfate (DHEAS) levels were found in 32% of women with PCOS. In non-PCOS women, dehydroepiandrosterone (DHEA) and its sulfate had no predictive role concerning clinical, anthropometric, and metabolic parameters. In PCOS women, mainly in the hyperandrogenemic group, DHEA showed to be a significant predictor against most anthropometric-metabolic index abnormalities (odds ratio [OR] = 0.36-0.97; p < 0.05), and an increase in triglycerides (TG) levels (OR = 0.76; p = 0.006). Dehydroepiandrosterone sulfate presented a few predictive effects regarding PCOS-associated disorders. In controls, DHEAS predicted against the increase in estimated average glucose (OR= 0.38; p = 0.036). In the normoandrogenic group, it predicted against elevation in the waist/hip ratio (WHR) (OR= 0.59; p = 0.042), and in hyperandrogenemic PCOS women, it predicted against abnormality in the conicity index (CI) (OR = 0.31; p = 0.028).

CONCLUSION

 Dehydroepiandrosterone was shown to be a better predictor of abnormal anthropometric and biochemical parameters in women with PCOS than DHEAS. Thus, regarding adrenal prohormones, DHEA measurement, instead of DHEAS, should be preferred in PCOS management. The effects of androgen prohormones on the prediction of PCOS abnormalities are weak.

Selective Inhibition of 11β-Hydroxysteroid Dehydrogenase Type 1 Attenuates High-Fat Diet-Induced Hepatic Steatosis in Mice

Introduction

The effect of 11β-hydroxysteroid dehydrogenase type1 (11β-HSD1) inhibition on hepatic steatosis is incompletely understood. Here, we aimed to determine the therapeutic effect of BVT.2733, a selective 11β-HSD1 inhibitor, on hepatic steatosis.

Materials and Methods

C57B/6J mice were randomly divided into a low-fat diet (LFD) fed group and a high-fat diet (HFD) fed group. Mice were fed with HFD for 28 weeks which induced obesity and severe hepatic steatosis. The two groups were further divided into four groups as follows: LFD, LFD with BVT.2733, HFD, and HFD with BVT.2733. Mice in LFD+BVT and HFD+BVT groups were intraperitoneally injected with BVT.2733 daily for 30 days. Effects of BVT.2733 on mice body weight, serum lipid profile, serum free fatty acids (FFAs), glucocorticoid levels, gene expression in adipose and liver tissues were assessed.

Results

Injection of a low dose of BVT.2733 (50 mg/kg/day) reduced body weight and hyperlipidemia, but did not improve glucose tolerance and insulin resistance in diet-induced obese mice. The low dose of BVT.2733 attenuated hepatic steatosis, liver injury, and liver lipolytic gene expression in diet-induced obese mice. Besides, the low dose of BVT.2733 reduced fat mass and lipolysis in visceral adipose tissues, hepatic FFAs, and serum corticosterone levels in diet-induced obese mice.

Conclusion

Our study shows that moderate inhibition of 11β-HSD1 by BVT.2733 reduces FFAs and corticosterone synthesis in fatty tissues, thereby attenuates the delivery of corticosterone and FFAs to the liver. Collectively, this prevents high-fat diet-induced hepatic steatosis.

Obesity, metabolic syndrome, and primary hypertension

Primary hypertension is the dominant form of arterial hypertension in adolescents. Disturbed body composition with, among other things, increased visceral fat deposition, accelerated biological maturation, metabolic abnormalities typical for metabolic syndrome, and increased adrenergic drive constitutes the intermediary phenotype of primary hypertension. Metabolic syndrome is observed in 15-20% of adolescents with primary hypertension. These features are also typical of obesity-related hypertension. Metabolic abnormalities and metabolic syndrome are closely associated with both the severity of hypertension and the risk of target organ damage. However, even though increased body mass index is the main determinant of blood pressure in the general population, not every hypertensive adolescent is obese and not every obese patient suffers from hypertension or metabolic abnormalities typical for metabolic syndrome. Thus, the concepts of metabolically healthy obesity, normal weight metabolically unhealthy, and metabolically unhealthy obese phenotypes have been developed. The risk of hypertension and hypertensive target organ damage increases with exposure to metabolic risk factors which are determined by disturbed body composition and visceral obesity. Due to the fact that both primary hypertension and obesity-related hypertension present similar pathogenesis, the principles of treatment are the same and are focused not only on lowering blood pressure, but also on normalizing body composition and metabolic abnormalities.

Associations between markers of mammary adipose tissue dysfunction and breast cancer prognostic factors

BACKGROUND

Obesity fosters worse clinical outcomes in both premenopausal and postmenopausal women with breast cancer. Emerging evidence suggests that an android body fat distribution in particular is deleterious for breast cancer prognosis. The extent of adipose tissue dysfunction, especially how it relates to breast cancer prognostic factors and anthropometric measurements, has not been fully investigated.

OBJECTIVE

Our objective was to examine if markers of adipose tissue dysfunction, such as hypertrophy and macrophage accumulation, are relevant for the pathophysiology of breast cancer and its associated prognostic factors in a well-characterised cohort of women with breast cancer who did not receive treatment before surgery.

METHODS

A consecutive series of 164 women with breast cancer provided breast adipose tissue sample. Multivariate generalised linear models were used to test associations of anthropometric indices and prognostic factors with markers of adipose tissue dysfunction.

RESULTS

We found associations of breast adipocyte size and macrophage infiltration (number of CD68+ cells/100 adipocytes) with adiposity, particularly a strong association between breast adipocyte size and central obesity, independent of total adiposity, age and menopausal status (β_adj = 0.87; p = 0.0001). We also identified relationships of adipocyte hypertrophy and macrophage infiltration with prognostic factors, such as cancer stage and tumour grade (p < 0.05). RNA expression of pro-inflammatory cytokines (IL6, TNF) and leptin was also increased as a function of adipocyte size and CD86+/CD11c+ macrophage number/100 adipocytes (p < 0.05).

CONCLUSIONS

Our findings support the model of dysfunctional adipose tissue in obesity-associated breast cancer.

The cortisol burden in elderly subjects with metabolic syndrome and its association with low-grade inflammation

BACKGROUND

Elderly people are exposed to an increased load of stressful events and neuro-hormonal stimulation is a key finding in metabolic syndrome and its related disorders.

AIMS

To determine the role of cortisol in elderly subjects, with or without metabolic syndrome (MetS), by means of a national multicentre observational study, AGICO (AGIng and Cortisol).

METHODS

From 2012 to 2017, the AGICO study enrolled n.339 subjects (aged > 65), after obtaining their informed consent. The investigators assessed a cardio-metabolic panel (including electrocardiogram, carotid ultrasonography and echocardiography), the presence of MetS (on Adult Treatment Panel III criteria), a neurological examination (including brain imaging), and cortisol activity (using a consecutive collection of diurnal and nocturnal urine).

RESULTS

In the patients presenting with MetS, the standardized diurnal and nocturnal cortisol excretion rates were 210.7 ± 145.5 and 173.7 ± 118.1 (mean ± standard deviation) μg/g creatinine/12 h; in those without MetS, the standardized diurnal and nocturnal cortisol excretion rates were 188.7 ± 92.7 and 144.1 ± 82.3 μg/g creatinine/12 h, respectively (nocturnal urinary cortisol in patients with MetS versus those without MetS p = 0.05, female patients with MetS vs female patients without MetS, p < 0.025). A significant positive correlation was found between the CRP levels and both the diurnal and nocturnal urinary cortisol levels with r = 0.187 (p < 0.025) and r = 0.411 (p < 0.00000001), respectively.

DISCUSSION

The elderly patients with MetS showed a trend towards increased standardized nocturnal cortisol excretions, with particular regard to the female subjects.

CONCLUSION

The positive correlation between cortisol excretion and low-grade inflammation suggests a common mechanism driving both hormonal and inflammatory changes.

Estrogens and Glucocorticoids in Mammary Adipose Tissue: Relationships with Body Mass Index and Breast Cancer Features

CONTEXT

Adipose tissue is an important site for extragonadal steroid hormone biosynthesis through the expression and activity of P450 aromatase, 11β-hydroxysteroid dehydrogenase (HSD) 1, and 17β-HSDs. The contribution of steroid hormones produced by adjacent adipose tissue for the progression and survival of breast tumors is unknown.

OBJECTIVE

To quantify estrogens (estradiol, estrone) and glucocorticoids (cortisol, cortisone) in breast adipose tissue from both healthy and diseased women and their relationships with adiposity indices and breast cancer prognostic markers.

DESIGN AND SETTING

Breast adipose tissue was collected at time of surgery.

PATIENTS

Pre- and postmenopausal women undergoing partial mastectomy for treatment of breast cancer (n = 17) or reduction mammoplasty (n = 6) were studied.

INTERVENTIONS

Relative estrogen and glucocorticoid amounts were determined by liquid chromatography tandem mass spectrometry.

RESULTS

The targeted steroids were reliably detected and quantified in mammary adipose tissues. Women with ER+/PR+ tumor had higher relative estradiol amount than women with ER-/PR- tumor (P < .05). The ratio of estradiol-to-estrone was higher in lean women than in women with a body mass index (BMI) ≥ 25 kg/m2 (P < .05). Mixed-model analyses showed that estradiol, cortisone, and cortisol were negatively associated with tumor size (P < .05). Relationships between glucocorticoids and tumor size remained significant after adjustment for BMI. The cortisol-to-cortisone ratio was negatively associated with tumor stage (P < .05) independently of BMI.

CONCLUSIONS

We reliably quantified estrogens and glucocorticoids in breast adipose tissue from healthy women and women suffering from breast cancer. Our findings suggest that smaller breast tumors are associated with higher relative amounts of estradiol and cortisol in adipose tissue.

Increased central adiposity and decreased subcutaneous adipose tissue 11β-hydroxysteroid dehydrogenase type 1 are associated with deterioration in glucose tolerance-A longitudinal cohort study

OBJECTIVE AND CONTEXT

Increasing adiposity, ageing and tissue-specific regeneration of cortisol through the activity of 11β-hydroxysteroid dehydrogenase type 1 have been associated with deterioration in glucose tolerance. We undertook a longitudinal, prospective clinical study to determine if alterations in local glucocorticoid metabolism track with changes in glucose tolerance.

DESIGN, PATIENTS, AND MEASUREMENTS

Sixty-five overweight/obese individuals (mean age 50.3 ± 7.3 years) underwent oral glucose tolerance testing, body composition assessment, subcutaneous adipose tissue biopsy and urinary steroid metabolite analysis annually for up to 5 years. Participants were categorized into those in whom glucose tolerance deteriorated ("deteriorators") or improved ("improvers").

RESULTS

Deteriorating glucose tolerance was associated with increasing total and trunk fat mass and increased subcutaneous adipose tissue expression of lipogenic genes. Subcutaneous adipose tissue 11β-HSD1 gene expression decreased in deteriorators, and at study completion, it was highest in the improvers. There was a significant negative correlation between change in area under the curve glucose and 11β-HSD1 expression. Global 11β-HSD1 activity did not change and was not different between deteriorators and improvers at baseline or follow-up.

CONCLUSION

Longitudinal deterioration in metabolic phenotype is not associated with increased 11β-HSD1 activity, but decreased subcutaneous adipose tissue gene expression. These changes may represent a compensatory mechanism to decrease local glucocorticoid exposure in the face of an adverse metabolic phenotype.

Autonomous cortisol secretion in adrenal incidentalomas and increased visceral fat accumulation during follow-up

OBJECTIVE

Autonomous cortisol secretion of adrenal incidentalomas (AIs) is associated with poor cardiovascular outcome. Because centripetal obesity is a cardiovascular risk factor, we aimed to investigate whether autonomous cortisol secretion is associated with increased visceral fat accumulation.

DESIGN

Retrospective cohort study.

PATIENTS

Patients with AIs who attended for follow-up between January 2014 and December 2016 were evaluated. Autonomous cortisol secretion was diagnosed when 1 mg overnight dexamethasone (post-DST) cortisol was >50 nmol/L at baseline and follow-up. Follow-up duration was 34 (12-105) months. Thirty patients with nonfunctioning AIs and 44 patients with autonomous cortisol secretion were included. Adrenalectomy was performed in five patients. Six patients with Cushing's syndrome were also recruited.

MEASUREMENTS

Hormonal evaluation and assessment of total (T), visceral (V) and subcutaneous (S) fat area by computed tomography and calculation of V:S and V:T ratios at baseline and follow-up.

RESULTS

V, V:S and V:T increased (P<.001 for each comparison, Wilcoxon signed rank test for repeated measures) in patients with autonomous cortisol secretion while did not change significantly in patients with nonfunctioning adenomas. Linear regression models including post-DST cortisol, gender, concomitant treatments and follow-up duration showed that both baseline and follow-up DST significantly predicted Δ(V:S) and Δ(V:T) (P<.01 for all models).

CONCLUSIONS

In patients with AIs, a post-DST cortisol >50 nmol/L at both baseline and follow-up, was associated with a significant increase in visceral fat after a follow-up duration of ~3 years. This may be of importance to explain the link between autonomous cortisol secretion and poor cardiovascular outcome.

Curcumin limits weight gain, adipose tissue growth, and glucose intolerance following the cessation of exercise and caloric restriction in rats

Weight regain, adipose tissue growth, and insulin resistance can occur within days after the cessation of regular dieting and exercise. This phenomenon has been attributed, in part, to the actions of stress hormones as well as local and systemic inflammation. We investigated the effect of curcumin, a naturally occurring polyphenol known for its anti-inflammatory properties and inhibitory action on 11β-HSD1 activity, on preserving metabolic health and limiting adipose tissue growth following the cessation of daily exercise and caloric restriction (CR). Sprague-Dawley rats (6-7 wk old) underwent a "training" protocol of 24-h voluntary running wheel access and CR (15-20 g/day; ~50-65% of ad libitum intake) for 3 wk ("All Trained") or were sedentary and fed ad libitum ("Sed"). After 3 wk, All Trained were randomly divided into one group which was terminated immediately ("Trained"), and two detrained groups which had their wheels locked and were reintroduced to ad libitum feeding for 1 wk. The wheel locked groups received either a daily gavage of a placebo ("Detrained + Placebo") or curcumin (200 mg/kg) ("Detrained + Curcumin"). Cessation of daily CR and exercise caused an increase in body mass, as well as a 9- to 14-fold increase in epididymal, perirenal, and inguinal adipose tissue mass, all of which were attenuated by curcumin ( P < 0.05). Insulin area under the curve (AUC) during an oral glucose tolerance test, HOMA-IR, and C-reactive protein (CRP) were elevated 6-, 9-, and 2-fold, respectively, in the Detrained + Placebo group vs. the Trained group (all P < 0.05). Curcumin reduced insulin AUC, HOMA-IR, and CRP vs. the placebo group (all P < 0.05). Our results indicate that curcumin has a protective effect against weight regain and impaired metabolic control following a successful period of weight loss through diet and exercise, perhaps via inhibition of glucocorticoid action and inflammation. NEW & NOTEWORTHY Weight regain after dieting and exercise is a common phenomenon plaguing many individuals. The biological mechanisms underlying weight regain are incompletely understood and are likely multifactorial. In this paper, we examined the metabolic implications of curcumin, a compound known for its anti-inflammatory properties and inhibitory action on the enzyme 11β-HSD1, in a rodent model of adiposity rebound after the cessation of diet and exercise.

The Role of the Growth Hormone/Insulin-Like Growth Factor System in Visceral Adiposity

There is substantial evidence that the growth hormone (GH)/insulin-like growth factor (IGF) system is involved in the pathophysiology of obesity. Both GH and IGF-I have direct effects on adipocyte proliferation and differentiation, and this system is involved in the cross-talk between adipose tissue, liver, and pituitary. Transgenic animal models have been of importance in identifying mechanisms underlying these interactions. It emerges that this system has key roles in visceral adiposity, and there is a rationale for targeting this system in the treatment of visceral obesity associated with GH deficiency, metabolic syndrome, and lipodystrophies. This evidence is reviewed, gaps in knowledge are highlighted, and recommendations are made for future research.

Impact of Glucocorticoid Excess on Glucose Tolerance: Clinical and Preclinical Evidence

Glucocorticoids (GCs) are steroid hormones that exert important physiological actions on metabolism. Given that GCs also exert potent immunosuppressive and anti-inflammatory actions, synthetic GCs such as prednisolone and dexamethasone were developed for the treatment of autoimmune- and inflammatory-related diseases. The synthetic GCs are undoubtedly efficient in terms of their therapeutic effects, but are accompanied by significant adverse effects on metabolism, specifically glucose metabolism. Glucose intolerance and reductions in insulin sensitivity are among the major concerns related to GC metabolic side effects, which may ultimately progress to type 2 diabetes mellitus. A number of pre-clinical and clinical studies have aimed to understand the repercussions of GCs on glucose metabolism and the possible mechanisms of GC action. This review intends to summarize the main alterations that occur in liver, skeletal muscle, adipose tissue, and pancreatic islets in the context of GC-induced glucose intolerance. For this, both experimental (animals) and clinical studies were selected and, whenever possible, the main cellular mechanisms involved in such GC-side effects were discussed.

Recent advances in the role of cortisol and metabolic syndrome in age-related degenerative diseases

The metabolic syndrome (MetS) presents an increasing prevalence in elderly people. A significant role in MetS is played by the stress response and cortisol. The hypothalamic-pituitary-adrenal (HPA) axis activity is increased by central (loss of hippocampal glucocorticoid receptors) and peripheral (11β-hydroxysteroid dehydrogenase type 1, 11β-HSD1, hyperactivity) mechanisms. The HPA hyperactivity has been found in chronic diseases affecting the endocrine (abdominal obesity with MetS, type 2 diabetes), cardiovascular (atherosclerosis, essential hypertension), and nervous systems (dementia, depression), in aging. A novel therapeutic approach (11β-HSD1 inhibition) is promising in treating the HPA axis hyperactivity in chronic diseases with MetS. A large-scale national clinical trial (AGICO, AGIng, and COrtisol study) has been proposed by our group to evaluate the role of cortisol and MetS in the main pathologies of aging (vascular and degenerative dementia, cardiovascular diseases, type 2 diabetes, abdominal obesity).

Vitamin D receptor Cdx-2-dependent response of central obesity to vitamin D intake in the subjects with type 2 diabetes: a randomised clinical trial

This study aimed to investigate the effects of daily intake of vitamin D-fortified yogurt drink (doogh) on central obesity indicators in subjects with type 2 diabetes (T2D) and the possible modulation of this effect by vitamin D receptor (VDR) Cdx-2 genotypes. A total of sixty T2D subjects were randomly allocated to two groups to receive either plain doogh (PD; n 29, containing 170 mg Ca and no vitamin D/250 ml) or vitamin D3-fortified doogh (FD; n 31, containing 170 mg Ca and 12·5 μg/250 ml) twice a day for 12 weeks. 25-hydroxyvitamin D (25(OH)D), glycaemic as well as adiposity indicators were evaluated before and after the intervention. VDR-Cdx-2 genotypes in extended number of T2D subjects in the FD group (n 60) were determined as AA, GA and GG. After 12 weeks, in FD compared with PD, serum 25(OH)D increased (+35·4 v. -4·8 nmol/l; P<0·001) and mean changes of waist circumference (WC; -1·3 v. +1·6 cm; P=0·02), body fat mass (FM; -1·9 v. +0·60 %; P=0·008), truncal fat (TF; -1·1 v. 0·13 %; P=0·003) and visceral adipose tissue (-0·80 v. +0·37 AU; P<0·001) decreased significantly. Circulating 25(OH)D was raised only in the AA group (34·8 nmo/l in AA group v. -6·4 nmol/l in AG and -1·6 nmol/l in GG groups; P<0·001), which was accompanied by a significant decrease in changes of WC (P=0·004), FM% (P=0·01) and TF% (P<0·001) in the AA genotype. Daily intake of vitamin D-FD for 12 weeks improved the central obesity indices in T2D subjects, and the improvement was more pronounced in the carriers of the AA genotype of VDR-Cdx-2.

Hepatic and visceral adipose tissue 11βHSD1 expressions are markers of body weight loss after bariatric surgery

OBJECTIVE

Cortisolemia and 11βHSD1 in liver and adipose tissue are altered in obesity. However, their participation in the development of obesity remains unclear. This study analyzed these parameters in the transition from morbid to type 1 obesity after bariatric surgery.

METHODS

A group of 34 patients with morbid obesity and 22 nonobese subjects were recruited. Initial hypothalamus-pituitary-adrenal (HPA) basal activity and 11βHSD1 mRNA expression in liver, subcutaneous (SAT), and visceral adipose tissue (VAT) were evaluated. A year after bariatric surgery (weight loss of 48 kg), these parameters were reappraised in plasma, SAT, and liver.

RESULTS

Body weight loss was accompanied by a downshift in basal HPA activity and 11βHSD1 expression in SAT. In patients with morbid obesity, 11βHSD1 expression correlated positively with BMI in VAT and negatively in liver at 6 and 12 months after surgery. In SAT, a correlation was observed with body weight only when patients showed type 1 obesity. Insulin, glucose, and HOMA correlated positively with all the HPA indicators and 11βHSD1 expression in SAT.

CONCLUSIONS

Body weight loss after bariatric surgery is accompanied by a downshift in basal HPA activity. Hepatic and VAT 11βHSD1 expressions in morbid obesity are predictors of body weight loss.

Updated survey of the steroid-converting enzymes in human adipose tissues

Over the past decade, adipose tissues have been increasingly known for their endocrine properties, that is, their ability to secrete a number of adipocytokines that may exert local and/or systemic effects. In addition, adipose tissues have long been recognized as significant sites for steroid hormone transformation and action. We hereby provide an updated survey of the many steroid-converting enzymes that may be detected in human adipose tissues, their activities and potential roles. In addition to the now well-established role of aromatase and 11β-hydroxysteroid dehydrogenase (HSD) type 1, many enzymes have been reported in adipocyte cell lines, isolated mature cells and/or preadipocytes. These include 11β-HSD type 2, 17β-HSDs, 3β-HSD, 5α-reductases, sulfatases and glucuronosyltransferases. Some of these enzymes are postulated to bear relevance for adipose tissue physiology and perhaps for the pathophysiology of obesity. This elaborate set of steroid-converting enzymes in the cell types of adipose tissue deserves further scientific attention. Our work on 20α-HSD (AKR1C1), 3α-HSD type 3 (AKR1C2) and 17β-HSD type 5 (AKR1C3) allowed us to clarify the relevance of these enzymes for some aspects of adipose tissue function. For example, down-regulation of AKR1C2 expression in preadipocytes seems to potentiate the inhibitory action of dihydrotestosterone on adipogenesis in this model. Many additional studies are warranted to assess the impact of intra-adipose steroid hormone conversions on adipose tissue functions and chronic conditions such as obesity, diabetes and cancer.

Association of HSD11B1 polymorphic variants and adipose tissue gene expression with metabolic syndrome, obesity and type 2 diabetes mellitus: a systematic review

The HSD11B1 gene is highly expressed in abdominal adipose tissue, and the enzyme it encodes catalyzes the interconversion of inactive cortisone to hormonally active cortisol. Genetic abnormalities of HSD11B1 have been associated with the development of abnormal glucose metabolism and body fat distribution. To systematically review studies evaluating the association of HSD11B1 gene expression in abdominal adipose tissue and HSD11B1 polymorphisms with obesity, the metabolic syndrome (MetS), and type 2 diabetes (T2DM), we conducted a search in MEDLINE, SCOPUS, and Cochrane Library databases in April 2015. The inclusion criteria were observational studies (cross-sectional, cohort, or case-control), conducted in adults, which analyzed the relationship of HSD11B1 polymorphisms and/or HSD11B1 expression in abdominal adipose tissue with obesity, MetS, or T2DM. Of 802 studies retrieved, 32 met the inclusion criteria (23 gene expression and 9 polymorphism studies). Twenty one studies analyzed the relationship between abdominal subcutaneous and/or visceral HSD11B1 expression with central and/or generalized obesity. Most studies reported that abdominal adipose HSD11B1 expression increased with increasing body mass index (15 studies) and abnormalities of glucose metabolism (7 studies), and varied with the presence of MetS (3 studies). Nine studies analyzed the association of 26 different HSD11B1 polymorphic variants with obesity, MetS, and T2DM. Only an Indian study found an association between a polymorphic variant at the HSD11B1 gene with MetS whereas in Pima Indians another polymorphic variant was found to be associated with T2DM. While the literature suggests that HSD11B1 is hyperexpressed in abdominal adipose tissue in subjects with obesity and abnormal glucose metabolism, this seems to be not true for HSD11B1 gene expression and MetS. Although an association of polymorphic variants of HSD11B1 with MetS in Indians and in the T2DM population of Pima Indians were found, most studies did not find a relationship between genetic polymorphic variants of HSD11B1 and obesity, MetS, and T2DM. Their reported conflicting and inconclusive results, suggesting that polymorphic variants of HSD11B1 may have only a small role in the development of metabolic abnormalities of susceptible populations in the development of MetS and T2DM.

No relative increase in intra-abdominal adipose tissue in healthy unstressed preterm infants at term

BACKGROUND

Preterm infants may be at risk for altered adiposity, a known risk factor for unfavorable metabolic and cardiovascular outcomes.

OBJECTIVES

The aim was to compare body composition (total body fat mass (FM), subcutaneous and intra-abdominal adipose tissue (AT)) between infants born preterm and at term.

METHODS

We conducted an observational, cross-sectional study that involved 50 infants born preterm free from major co-morbidities and 34 term healthy breastfed infants. Anthropometric measurements, body composition (total body FM, subcutaneous and intra-abdominal AT) were assessed at 40-42 weeks postconceptional age for preterm infants and within 15 days of birth for term infants. Total body FM was assessed by an air displacement plethysmography system and subcutaneous abdominal and intra-abdominal AT were assessed by magnetic resonance imaging using a commercially available software program.

RESULTS

Compared to term infants, mean (SD) total body FM (g) (636.7 (247) vs. 418.4 (253), p < 0.0001) and mean (SD) subcutaneous abdominal AT (g) (123 (36) vs. 98.9 (22), p < 0.001) were significantly higher in preterm infants but mean (SD) fat-free mass (g) (2,530 (420) vs. 2,965 (389), p < 0.0001) and mean (SD) intra-abdominal AT (10.9 (5.2) vs. 18.2 (13.2), p = 0.001) were significantly lower.

CONCLUSIONS

In the absence of severe illness during the hospital stay, prematurity, although associated with increased total body FM, does not appear to be associated with a relative increase in intra-abdominal AT compared to term infants.

Androgens, body fat Distribution and Adipogenesis

Androgens are regulators of important adipocyte functions such as adipogenesis, lipid storage, and lipolysis. Through depot-specific impact on the cells of each fat compartment, androgens could modulate body fat distribution patterns in humans. Testosterone and dihydrotestosterone have been shown to inhibit the differentiation of preadipocytes to lipid-storing adipocytes in several models including primary cultures of human adipocytes from both men and women. Androgen effects have also been observed on some markers of lipid metabolism such as LPL activity, fatty acid uptake, and lipolysis. Possible depot-specific and sex-specific effects have been observed in some but not all models. Transformation of androgen precursors to active androgens or their inactivation by enzymes that are expressed and functional in adipose tissue may contribute to modulate the local availability of active hormones. These phenomena, along with putative depot-specific interactions with glucocorticoids may contribute to human body fat distribution patterns.

Cross-sectional associations of acylation stimulating protein (ASP) and adipose tissue gene expression with estradiol and progesterone in pre- and postmenopausal women

OBJECTIVE

Sex steroid hormones play an important regulatory role in fat metabolism and obesity. We hypothesized involvement of interactions between ovarian hormones with acylation stimulating protein (ASP).

DESIGN, PATIENTS AND MEASUREMENTS

In 392 women with wide age (18-69 years) and body size (BMI: 17 to 90 kg/m(2) ) ranges, fasting plasma levels of ASP, ovarian hormones, glucose, adiponectin and lipids/apolipoproteins were assessed, along with determination of metabolic syndrome (MS) features. Gene expression of C3 (ASP precursor) and related receptors C5L2, C3aR and C5aR in subcutaneous and omental adipose tissues was measured in a subset.

RESULTS

Acylation stimulating protein correlated negatively with concentrations of estradiol (P < 0·0001), adiponectin (P < 0·001) and apolipoprotein A1 (P < 0·001) and positively with apolipoprotein B levels (P < 0·001), systolic blood pressure (P < 0·001), waist circumference (P < 0·001), and triglyceride concentrations (P < 0·01). In age-matched groups of lean, overweight, metabolically healthy obese (MHO) and obese with metabolic syndrome (MSO), there was a stepwise increase in ASP levels (P < 0·001) while concentrations of adiponectin (P < 0·0001) and estradiol (P < 0·001) but not those of progesterone decreased. Progesterone but not estradiol levels correlated positively with C3 gene expression in omental adipose tissue (P < 0·05) and negatively with C5L2 expression in both omental (P < 0·01) and subcutaneous (P < 0·05) adipose tissues.

CONCLUSION

Our results are consistent with the concept that sex hormones differentially influence circulating ASP and adipose tissue gene expression of its related proteins in a depot-specific manner. ASP may play a role in the regulation of regional fat metabolism through interactions with sex hormones in women.

Consumption of green coffee reduces blood pressure and body composition by influencing 11β-HSD1 enzyme activity in healthy individuals: a pilot crossover study using green and black coffee

Dietary polyphenols may have a protective role against the development of CVD. Thus, we aimed to investigate the effects of green coffee (GC), rich in chlorogenic acid, and black coffee (BC) on cardiovascular markers. A randomised pilot crossover study was performed on healthy subjects who consumed both coffees for 2 weeks. We measured anthropometry, blood pressure, and arterial elasticity after each intervention and collected urine samples to monitor antioxidant capacity. Free cortisol and cortisone levels were obtained from urine and analysed by specific ELISA methods. Systolic blood pressure (P = 0.018) and arterial elasticity (P = 0.001) were significantly reduced after GC. BMI (P = 0.04 for BC; P = 0.01 for GC) and abdominal fat (P = 0.01 for BC; P = 0.009 for GC) were also significantly reduced with no changes in energy intake. Urinary free cortisol was significantly reduced from 125.6 ± 85.9 nmol/day to 76.0 ± 54.9 nmol/day following GC and increased to 132.1 ± 89.1 nmol/day after BC. Urinary free cortisone increased by 18% following BC and 9% following GC (nonsignificant). Cortisol/cortisone ratio (indicating 11β-HSD1 activity) was reduced after GC (from 3.5 ± 1.9 to 1.7 ± 1.04, P = 0.002). This suggests that GC can play a role in reducing cardiovascular risk factors. Further research including hypertensive and overweight individuals will now be justified to clarify whether GC could have a therapeutic role in CVD.

Tissue-specific dysregulation of cortisol regeneration by 11βHSD1 in obesity: has it promised too much?

Cushing's syndrome, caused by increased production of cortisol, leads to metabolic dysfunction including visceral adiposity, hypertension, hyperlipidaemia and type 2 diabetes. The similarities with the metabolic syndrome are striking and major efforts have been made to find obesity-associated changes in the regulation of glucocorticoid action and synthesis, both at a systemic level and tissue level. Obesity is associated with tissue-specific alterations in glucocorticoid metabolism, with increased activity of the glucocorticoid-regenerating enzyme 11β-hydroxysteroid dehydrogenase type 1 (11βHSD1) in subcutaneous adipose tissue and decreased conversion of cortisone to cortisol, interpreted as decreased 11βHSD1 activity, in the liver. In addition, genetic manipulation of 11βHSD1 activity in rodents can either induce (by overexpression of Hsd11b1, the gene encoding 11βHSD1) or prevent (by knocking out Hsd11b1) obesity and metabolic dysfunction. Taken together with earlier evidence that non-selective inhibitors of 11βHSD1 enhance insulin sensitivity, these results led to the hypothesis that inhibition of 11βHSD1 might be a promising target for treatment of the metabolic syndrome. Several selective 11βHSD1 inhibitors have now been developed and shown to improve metabolic dysfunction in patients with type 2 diabetes, but the small magnitude of the glucose-lowering effect has precluded their further commercial development.This review focuses on the role of 11βHSD1 as a tissue-specific regulator of cortisol exposure in obesity and type 2 diabetes in humans. We consider the potential of inhibition of 11βHSD1 as a therapeutic strategy that might address multiple complications in patients with type 2 diabetes, and provide our thoughts on future directions in this field.

Identification of novel 11β-HSD1 inhibitors by combined ligand- and structure-based virtual screening

11 beta-hydroxysteroid dehydrogenase type 1 (11β-HSD1) converts cortisone to cortisol in a NADPH dependent manner. Overexpression of 11β-HSD1 in key metabolic tissues is related to the development of type 2 diabetes, obesity, hypertension and metabolic syndrome. Using crystal structures of human 11β-HSD1 in complex with inhibitors as source of structural information, a combined ligand and structure-based virtual screening approach was implemented to identify novel 11β-HSD1 inhibitors. A selected group of compounds was identified in silico and further evaluated in cell-based assays for cytotoxicity and 11β-HSD1 mediated cortisol production inhibitory capacity. The expression of 11β-HSD1 and 11β-HSD2 in human LS14 adipocytes was assessed during differentiation. Biological evaluation of 39 compounds in adipocytes and steroids quantification by HPLC-MS/MS identify 4 compounds that exhibit 11β-HSD1 mediated cortisol production inhibitory activity with potencies in the micromolar range. Two compounds showed to be selective for the 11β-HSD1 reductase activity and over 11β-HSD2 isoform, and thus represent novel leads for the development of more active derivatives with higher efficacies targeting intracellular cortisol levels in type 2 diabetes and metabolic syndrome.

Mechanisms of glucocorticoid-induced insulin resistance: focus on adipose tissue function and lipid metabolism

Glucocorticoids (GCs) are critical in the regulation of the stress response, inflammation and energy homeostasis. Excessive GC exposure results in whole-body insulin resistance, obesity, cardiovascular disease, and ultimately decreased survival, despite their potent anti-inflammatory effects. This apparent paradox may be explained by the complex actions of GCs on adipose tissue functionality. The wide prevalence of oral GC therapy makes their adverse systemic effects an important yet incompletely understood clinical problem. This article reviews the mechanisms by which supraphysiologic GC exposure promotes insulin resistance, focusing in particular on the effects on adipose tissue function and lipid metabolism.

The temporal characterization of marrow lipids and adipocytes in a rabbit model of glucocorticoid-induced osteoporosis

OBJECTIVE

To characterize the temporal changes in marrow lipids content and adipocytes in the development of glucocorticoid-induced osteoporosis (GIOP) in rabbits using MR spectroscopy.

SUBJECTS AND METHODS

Twenty 20-week-old female rabbits were randomized to a control group and a GIOP group equally. Marrow lipids fraction and bone mineral density at the left proximal femur and L3-L4 vertebrae were measured by MR spectroscopy and dual-energy X-ray absorptiometry at week 0, 4, 8, and 12. Marrow adipocytes were quantitatively evaluated by histopathology.

RESULTS

Marrow adiposity in the GIOP group showed a significant increase over time, with a variation of marrow lipids fraction (+35.9 %) at week 4 from baseline and it was maintained until week 12 (+75.2 %, p < 0.001 for all). The GIOP group demonstrated continuous deterioration of bone with significant difference between the two groups at week 8, followed by increased marrow fat with significant difference at week 4 (p < 0.05 for all). In comparison with the controls, marrow adipocyte density in the GIOP group increased by 57.1 % at week 8 and 35.4 % at week 12, respectively. A reduction (-13.3 %) in adipocyte mean diameter at week 8 (but an increase (+22.7 %) at week 12) were observed in the GIOP group compared with the control group (p < 0.05 for all). There was significant difference between two periods (p = 0.023) in adipocyte mean diameter in the GIOP group. The percentage area of marrow adipocytes in the GIOP group was 62.8 ± 8.7 % at week 8 and 79.2 ± 7.7 % at week 12, both of which were significantly higher than those of the controls (p < 0.05 for all).

CONCLUSIONS

Marrow adipogenesis is synchronized with bone loss in the development of GIOP, which was characterized by a significant increase in the number of small-sized marrow adipocytes in the relatively early stage and concomitant volume increase later on. MR spectroscopy appears to be the most powerful tool for detecting the sequential changes in marrow lipid content.

11β-Hydroxysteroid dehydrogenase 1: translational and therapeutic aspects

11β-Hydroxysteroid dehydrogenase type 1 (11β-HSD1) interconverts the inactive glucocorticoid cortisone and its active form cortisol. It is widely expressed and, although bidirectional, in vivo it functions predominantly as an oxoreductase, generating active glucocorticoid. This allows glucocorticoid receptor activation to be regulated at a prereceptor level in a tissue-specific manner. In this review, we will discuss the enzymology and molecular biology of 11β-HSD1 and the molecular basis of cortisone reductase deficiencies. We will also address how altered 11β-HSD1 activity has been implicated in a number of disease states, and we will explore its role in the physiology and pathologies of different tissues. Finally, we will address the current status of selective 11β-HSD1 inhibitors that are in development and being tested in phase II trials for patients with the metabolic syndrome. Although the data are preliminary, therapeutic inhibition of 11β-HSD1 is also an exciting prospect for the treatment of a variety of other disorders such as osteoporosis, glaucoma, intracranial hypertension, and cognitive decline.

Visceral fat accumulation and postdexamethasone serum cortisol levels in patients with adrenal incidentaloma

OBJECTIVE

Visceral fat is a significant cardiovascular risk factor. Because visceral fat has not been measured systematically in patients with adrenal incidentalomas, we have tested the hypothesis that visceral fat volume may be associated with cutoffs for serum cortisol levels post dexamethasone.

DESIGN

This was a retrospective, cross-sectional study.

SETTING

The study was conducted at the Endocrine Investigation Unit, University Teaching Hospital.

PARTICIPANTS

Seventy-three women and 52 men diagnosed with adrenal incidentalomas and 9 patients with overt Cushing's syndrome participated in this study.

MAIN OUTCOME MEASURES

The following was measured for serum cortisol level after dexamethasone suppression and visceral fat ratios: visceral-subcutaneous (V:S) and visceral-total volume (V:TV) measured by computed tomography.

RESULTS

Sixty-eight patients with a postdexamethasone serum cortisol greater than 1.8 μg/dL (50 nmol/L) showed a significantly higher mean V:S and V:TV fat ratio compared with those whose serum cortisol was less than 1.8 μg/dL: women, lnV:S, -0.45 vs -0.69 [mean difference 0.24 (95% confidence interval [CI] 0.08-0.41); P = .004] and V:TV, 0.39 vs 0.34 [mean difference 0.05 (95% CI 0.02-0.09); P = .004]; men, lnV:S, 0.64 vs 0.29 [mean difference 0.35 95% CI 0.08-0.63); P = .01] and V:TV, 0.65 vs 0.57 [mean difference 0.08 (95% CI 0.02-0.14); P = .02]. By ANOVA and post hoc analysis (Fisher's least significant differences), there was no difference in fat ratios between the postdexamethasone serum cortisol groups [1.8-2.9 μg/dL (50-82 nmol/L), 3.0-5.0 μg/dL (83-137 nmol/L), > 5.0 μg/dL (>138 nmol/L) and Cushing's syndrome (mean V:TV: 0.38, 0.40, 0.40, 0.41, respectively)], but they all differed significantly from the less than the 1.8-μg/dL group (V:TV: 0.34, P = .03).

CONCLUSION

Visceral fat is increased in patients with adrenal incidentalomas and a postdexamethasone serum cortisol of greater than 1.8 μg/dL and is similar to that found in patients with overt Cushing's syndrome.

Increases in systemic and local stress: a probable mechanism of visceral fat accumulation and insulin resistance in adult catch-up growth rats?

Catch-up growth in adult (CUGA) is increasingly proposed as an important causative factor for the widespread insulin resistance (IR)-related diseases especially in developing countries/territories. We aimed to investigate the effects of CUGA to insulin sensitivity, lipid profile and stress in rats, as well as the probable relationship among them. Male Sprague-Dawley rats were randomly divided into six groups for two sampling points: caloric restriction group (R4) and normal chow controls for four weeks (NC4); CUGA re-fed with normal chow (RN4), CUGA re-fed with high-fat diet (RH4), normal chow controls (NC8) and high-fat diet controls (HF8) for eight weeks. Visceral fat accumulation (visceral adipose tissue [VAT] percentage), systemic (plasma corticosterone) and local (HSD11B1 mRNA expression in skeletal muscle [SkM] and VAT) stress, whole-body and peripheral insulin sensitivity were determined in this study. After four weeks of caloric restriction, R4 rats showed increases in systemic and local stress, decreases in visceral fat accumulation and no IR (whole-body or peripheral). Yet, after re-feeding, sustained systemic and local stress, remarkable visceral fat accumulation and IR (whole-body and peripheral) were found in RN4 compared with NC8, in RH4 compared with NC8 and HF8. Our findings demonstrated that CUGA rats were characterized by significant IR, visceral fat accumulation and stress. These changes were more severe in CUGA re-fed with high-fat diet. The interaction of sustained caloric restriction-induced stress and re-feeding might be of utmost importance in the etiology of visceral fat accumulation and IR in CUGA.

Pathophysiology of human visceral obesity: an update

Excess intra-abdominal adipose tissue accumulation, often termed visceral obesity, is part of a phenotype including dysfunctional subcutaneous adipose tissue expansion and ectopic triglyceride storage closely related to clustering cardiometabolic risk factors. Hypertriglyceridemia; increased free fatty acid availability; adipose tissue release of proinflammatory cytokines; liver insulin resistance and inflammation; increased liver VLDL synthesis and secretion; reduced clearance of triglyceride-rich lipoproteins; presence of small, dense LDL particles; and reduced HDL cholesterol levels are among the many metabolic alterations closely related to this condition. Age, gender, genetics, and ethnicity are broad etiological factors contributing to variation in visceral adipose tissue accumulation. Specific mechanisms responsible for proportionally increased visceral fat storage when facing positive energy balance and weight gain may involve sex hormones, local cortisol production in abdominal adipose tissues, endocannabinoids, growth hormone, and dietary fructose. Physiological characteristics of abdominal adipose tissues such as adipocyte size and number, lipolytic responsiveness, lipid storage capacity, and inflammatory cytokine production are significant correlates and even possible determinants of the increased cardiometabolic risk associated with visceral obesity. Thiazolidinediones, estrogen replacement in postmenopausal women, and testosterone replacement in androgen-deficient men have been shown to favorably modulate body fat distribution and cardiometabolic risk to various degrees. However, some of these therapies must now be considered in the context of their serious side effects. Lifestyle interventions leading to weight loss generally induce preferential mobilization of visceral fat. In clinical practice, measuring waist circumference in addition to the body mass index could be helpful for the identification and management of a subgroup of overweight or obese patients at high cardiometabolic risk.

11beta-Hydroxysteroid dehydrogenase type 1 inhibitors: novel agents for the treatment of metabolic syndrome and obesity-related disorders?

OBJECTIVE

Metabolic syndrome (MetS) and Cushing's syndrome share common features. It has been proposed that increased glucocorticoid activity at peripheral tissues may play a role in the pathogenesis of MetS and obesity-related disorders. It is well-known that intracellular cortisol concentrations are determined not only by plasma levels but also by the activity of 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) which catalyzes the conversion of inactive cortisone to active cortisol, especially in the liver and adipose tissue. Another isoenzyme exists, the 11β-hydroxysteroid dehydrogenase type 2, which acts in the opposite direction inactivating cortisol to cortisone in the kidney. This review considers the significance of the 11β-HSD1 inhibition in the treatment of several features of MetS and provides current data about the development of 11β-HSD1 inhibitors, as new agents for this purpose.

MATERIALS/METHODS

Using PubMed, we searched for publications during the last 20years regarding the development of 11β-HSD1 inhibitors.

RESULTS

Emerging data from animal and human studies indicate an association of 11β-HSD1 over-expression with obesity and disorders in glucose and lipid metabolism. This has led to the hypothesis that selective inhibition of 11β-HSD1 could be used to treat MetS and diabetes. Indeed, natural products and older agents such as thiazolidinediones and fibrates seem to exert an inhibitory effect on 11β-HSD1, ameliorating the cardiometabolic profile. In view of this concept, novel compounds, such as adamantyltriazoles, arylsulfonamidothiazoles, anilinothiazolones, BVT2733, INCB-13739, MK-0916 and MK-0736, are currently under investigation and the preliminary findings from both experimental and human studies show a favourable effect on glucose and lipid metabolism, weight reduction and adipokine levels.

CONCLUSIONS

Many compounds inhibiting 11β-ΗSD1 are under development and preliminary data about their impact on glucose metabolism and obesity-related disorders are encouraging.

Differences in Expression, Content, and Activity of 11β-HSD1 in Adipose Tissue between Obese Men and Women

Cortisol production in adipose tissue is regulated by 11β-HSD1. Objective. To determine whether there are differences in gene expression, enzyme activity, and protein content of the 11β-HSD1 enzyme in VAT (visceral adipose tissue) and SAT (subcutaneous adipose tissue) from obese compared to nonobese adults. Methods. VAT and SAT samples were obtained from 32 obese subjects (BMI > 30 Kg/m²) who underwent bariatric surgery and 15 samples from controls submitted to elective surgery. Fasting serum glucose, insulin, and lipids were measured. The expression of 11β-HSD1 was determined by RT-PCR, the enzyme activity by thin-layer chromatography, and the protein content by Western blot. Results. Obese patients had higher cholesterol, insulin, and HOMA-IR compared to nonobese. There were no differences in VAT or SAT expression of 11β-HSD1 between obese and nonobese patients. However, we found lower 11β-HSD1 activity and protein content in VAT, in obese women versus nonobese women (P < 0.05). BMI and 11β-HSD1 enzyme activity and protein content in VAT correlated inversely in women. Conclusions. Regulation of 11β-HSD1 activity in VAT from obese subjects appears to be gender specific, suggesting the existence of a possible protective mechanism modulating this enzyme activity leading to a decrease in the production of cortisol in this tissue.

The role of mediastinal adipose tissue 11β-hydroxysteroid d ehydrogenase type 1 and glucocorticoid expression in the development of coronary atherosclerosis in obese patients with ischemic heart disease

Background

Visceral fat deposition and its associated atherogenic complications are mediated by glucocorticoids. Cardiac visceral fat comprises mediastinal adipose tissue (MAT) and epicardial adipose tissue (EAT), and MAT is a potential biomarker of risk for obese patients.

Aim

Our objective was to evaluate the role of EAT and MAT 11beta-hydroxysteroid dehydrogenase type 1 (11β-HSD-1) and glucocorticoid receptor (GCR) expression in comparison with subcutaneous adipose tissue (SAT) in the development of coronary atherosclerosis in obese patients with coronary artery disease (CAD), and to assess their correlations with CD68 and fatty acids from these tissues.

Methods and results

Expression of 11β-HSD-1 and GCR was measured by qRT-PCR in EAT, MAT and SAT of thirty-one obese patients undergoing coronary artery bypass grafting due to CAD (obese CAD group) and sixteen obese patients without CAD undergoing heart valve surgery (controls). 11β-HSD-1 and GCR expression in MAT were found to be significantly increased in the obese CAD group compared with controls (p < 0.05). In the obese CAD group, 11β-HSD-1 and GCR mRNA levels were strongly correlated in MAT. Stearidonic acid was significantly increased in EAT and MAT of the obese CAD group and arachidonic acid was significantly expressed in MAT of the obese male CAD group (p < 0.05).

Conclusions

We report for the first time the increased expression of 11β-HSD-1 and GCR in MAT compared with EAT and SAT, and also describe the interrelated effects of stearidonic acid, HOMA-IR, plasma cortisol and GCR mRNA levels, explaining 40.2% of the variance in 11β-HSD-1 mRNA levels in MAT of obese CAD patients. These findings support the hypothesis that MAT contributes locally to the development of coronary atherosclerosis via glucocorticoid action.

Liver upregulation of genes involved in cortisol production and action is associated with metabolic syndrome in morbidly obese patients

BACKGROUND

Hepatic 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) activity, which converts cortisone (inactive) to cortisol, is downregulated in obesity. However, this compensation fails in obese with metabolic abnormalities, such as diabetes. To further characterize the tissue-specific cortisol regeneration in obesity, we have investigated the mRNA expression of genes related to local cortisol production, i.e., 11β-HSD1, hexose-6-phosphate dehydrogenase (H6PDH) and cortisol action, glucocorticoid receptor (GR) and a cortisol target gene, phosphoenolpyruvate carboxykinase (PEPCK) in the liver, and visceral (VAT) and subcutaneous (SAT) adipose tissues from morbidly obese patients with and without metabolic syndrome (MS).

METHODS

Fifty morbidly obese patients undergoing bariatric surgery, 14 men (mean age, 41.3 ± 3.5 years; BMI, 48.0 ± 3.6 kg/m(2)) and 36 women (mean age, 44.6 ± 1.9 years; BMI, 44.9 ± 1.2 kg/m(2)), were classified as having MS (MS+, n = 20) or not (MS-, n = 30). Tissue mRNA levels were measured by real-time polymerase chain reaction.

RESULTS

Hepatic mRNA levels of these genes were higher in obese patients with MS (11β-HSD1, P = 0.002; H6PDH, P = 0.043; GR, P = 0.033; PEPCK, P = 0.032) and positively correlated with the number of clinical characteristics that define the MS. The expression of the four genes positively correlated among them. In contrast to the liver, these genes were not differently expressed in VAT or SAT, when MS+ and MS- obese patients were compared.

CONCLUSIONS

Coordinated liver-specific upregulation of genes involved in local cortisol regeneration and action support the concept that local hepatic hypercortisolism contributes to development of MS in morbidly obese patients.

Glucocorticoid-induced androgen inactivation by aldo-keto reductase 1C2 promotes adipogenesis in human preadipocytes

Adipogenesis and lipid storage in human adipose tissue are inhibited by androgens such as DHT. Inactivation of DHT to 3α-diol is stimulated by glucocorticoids in human preadipocytes. We sought to characterize glucocorticoid-induced androgen inactivation in human preadipocytes and to establish its role in the antiadipogenic action of DHT. Subcutaneous and omental primary preadipocyte cultures were established from fat samples obtained in subjects undergoing abdominal surgeries. Inactivation of DHT to 3α/β-diol for 24 h was measured in dexamethasone- or vehicle-treated cells. Specific downregulation of aldo-keto reductase 1C (AKR1C) enzymes in human preadipocytes was achieved using RNA interference. In whole adipose tissue sample, cortisol production was positively correlated with androgen inactivation in both subcutaneous and omental adipose tissue (P < 0.05). Maximal dexamethasone (1 μM) stimulation of DHT inactivation was higher in omental compared with subcutaneous fat from men as well as subcutaneous and omental fat from women (P < 0.05). A significant positive correlation was observed between BMI and maximal dexamethasone-induced DHT inactivation rates in subcutaneous and omental adipose tissue of men and women (r = 0.24, n = 26, P < 0.01). siRNA-induced downregulation of AKR1C2, but not AKR1C1 or AKR1C3, significantly reduced basal and glucocorticoid-induced androgen inactivation rates (P < 0.05). The inhibitory action of DHT on preadipocyte differentiation was potentiated following AKR1C2 but not AKR1C1 or AKR1C3 downregulation. Specifically, lipid accumulation, G3PDH activity, and FABP4 mRNA expression in differentiated preadipocytes exposed to DHT were reduced further upon AKR1C2 siRNA transfection. We conclude that glucocorticoid-induced androgen inactivation is mediated by AKR1C2 and is particularly effective in omental preadipocytes of obese men. The interplay between glucocorticoids and AKR1C2-dependent androgen inactivation may locally modulate adipogenesis and lipid accumulation in a depot-specific manner.

Salicylate downregulates 11β-HSD1 expression in adipose tissue in obese mice and in humans, mediating insulin sensitization

Recent trials show salicylates improve glycemic control in type 2 diabetes, but the mechanism is poorly understood. Expression of the glucocorticoid-generating enzyme 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) in adipose tissue is increased in vitro by proinflammatory cytokines and upregulated in obesity. 11β-HSD1 inhibition enhances insulin sensitivity. We hypothesized that salicylates downregulate 11β-HSD1 expression, contributing to their metabolic efficacy. We treated diet-induced obese (DIO) 11β-HSD1-deficient mice and C57Bl/6 mice with sodium salicylate for 4 weeks. Glucose tolerance was assessed in vivo. Tissue transcript levels were assessed by quantitative PCR and enzyme activity by incubation with (3)H-steroid. Two weeks' administration of salsalate was also investigated in a randomized double-blind placebo-controlled crossover study in 16 men, with measurement of liver 11β-HSD1 activity in vivo and adipose tissue 11β-HSD1 transcript levels ex vivo. In C57Bl/6 DIO mice, salicylate improved glucose tolerance and downregulated 11β-HSD1 mRNA and activity selectively in visceral adipose. DIO 11β-HSD1-deficient mice were resistant to these metabolic effects of salicylate. In men, salsalate reduced 11β-HSD1 expression in subcutaneous adipose, and in vitro salicylate treatment reduced adipocyte 11β-HSD1 expression and induced adiponectin expression only in the presence of 11β-HSD1 substrate. Reduced intra-adipose glucocorticoid regeneration by 11β-HSD1 is a novel mechanism that contributes to the metabolic efficacy of salicylates.

The expression of omental 11β-HSD1 is not increased in severely obese women with metabolic syndrome

OBJECTIVE

Plasma cortisol in obese subjects does not differ from that in normoweight subjects. Extra-adrenal cortisol production by 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) can result in local hypercortisolemia. The aim of the present study was to examine the role of visceral hypercortisolemia in the development of metabolic syndrome in severe obesity.

METHODS

Eight lean women during hysterectomy (controls) and 19 severely obese women during bariatric surgery were studied, 8 without metabolic syndrome (OM- group) and 11 with it (OM+ group). Biopsies of omental and subcutaneous fat were performed in the severely obese women during surgery, but only omental biopsies in the controls. Expression of 11β-HSD1, glucocorticoid receptor α (GRα) and glucocorticoid receptor β (GRβ) was evaluated using real-time PCR.

RESULTS

Omental 11β-HSD1 expression was different between groups (one-way ANOVA, p < 0.01). Post-hoc analysis revealed that mean omental 11β-HSD1 mRNA levels were higher in the OM- group compared to controls, whereas they were similar when comparing the OM+ group with lean controls. Expression of 11β-HSD1 in subcutaneous fat was not different between OM+ and OM- groups. GRα expression in omental fat did not differ among groups or between omental and subcutaneous fat in severely obese patients. An expression of GRβ was not detected.

CONCLUSION

Contrary to our original hypothesis, omental 11β-HSD1 expression is not increased in the OM+ group.

Increased urinary glucocorticoid metabolites are associated with metabolic syndrome, hypoadiponectinemia, insulin resistance and β cell dysfunction

Metabolic syndrome (MetS) may have increased cortisol (F) production caused by 11β-hydroxysteroid dehydrogenase 1 (11β-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 (24h) F, E and THM levels. β 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-β 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-β (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 β 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.

Major depression, borderline personality disorder, and visceral fat content in women

Major depressive disorder (MDD) is associated with increased volumes of visceral fat and a high prevalence of the metabolic syndrome. In turn, affective disorders are frequently found in patients with borderline personality disorder (BPD). It is therefore unclear whether BPD per se may influence body composition. In order to clarify a potential relationship between BPD and body composition, we measured visceral fat content (VFC) in young depressed women with and without comorbid BPD and related this parameter to various features of the metabolic syndrome. Visceral fat content was measured by magnetic resonance imaging in 22 premenopausal women with MDD only, in 44 women with comorbid MDD and BPD, in 12 female BPD patients without MDD, and in 34 healthy women (CG). Data showed that depressed women without comorbid BPD had a 335% higher VFC and women with comorbid BPD had a 250% higher VFC than the CG women. When controlling for age, data showed significant effects of MDD on VFC (F = 8.4; P = 0.005). However, BPD, with or without MDD, was not related to VFC. Young depressed women with and without comorbid BPD display increased visceral fat content when compared to control subjects and may therefore constitute a risk group for the development of the metabolic syndrome. BPD per se is not an additive risk factor in this context.

Correlative studies on the effects of obesity, diabetes and hypertension on gene expression in omental adipose tissue of obese women

OBJECTIVE

A major consequence of obesity is the enormous expansion of and enhanced inflammatory response seen in visceral adipose tissue. I hypothesized that the expression of inflammatory markers in visceral omental fat would correlate with the extent of visceral adiposity as measured by waist circumference or body mass index and that diabetes and hypertension, defined as subjects taking anti-hypertensive drugs, would be associated with changes in mRNA expression in visceral fat.

DESIGN AND METHODS

The expression of 106 mRNAs by RT-PCR was examined in observational studies using extracts of omental fat of obese women undergoing bariatric surgery as well as the circulating levels of some adipokines. We also compared the mRNA levels of 65 proteins in omental fat removed during gastric bypass surgery of women with and without hypertension and those with type 2 diabetes.

RESULTS

Out of 106 mRNAs the expression of 10 mRNAs in omental fat of women not taking anti-hypertensive drugs correlated with waist circumference while 7 different mRNAs had significant correlations with circulating glucose. The correlations of waist circumference with mRNA expression were abolished, except for interleukin (IL)-1 receptor antagonist (IL-1RA), in women taking anti-hypertensive drugs. The correlations of blood glucose with omental fat mRNA expression were abolished, except for that of Akt1 and Akt2, in women taking anti-hypertensive drugs. However, the expression of 4 different mRNAs in omental fat was affected by circulating glucose in subjects taking anti-hypertensive drugs. The circulating levels of IL-1 RA, but not fatty acid binding protein 4, adipsin and phospholipase A2, correlated with both waist circumference and mRNA expression in omental fat.

CONCLUSION

In female bariatric surgery patients, the mRNA expression of some proteins in omental fat was affected by the degree of obesity, whereas hypertension and diabetes affected a separate set of mRNAs.Nutrition and Diabetes (2011) 1, e17; doi:10.1038/nutd.2011.14; published online 26 September 2011.

Elevated serum 25(OH)D concentrations, vitamin D, and calcium intakes are associated with reduced adipocyte size in women

Recent studies have suggested a beneficial effect of vitamin D and calcium on adipocyte metabolism and the metabolic profile. Our objective was to examine associations of vitamin D intake, calcium and dairy products as well as serum 25(OH)D concentration with adiposity measures and adipocyte size in women. Omental and subcutaneous adipose tissue samples were obtained from 43 women undergoing gynecological surgeries. Adipocyte size was measured using adipocyte suspensions from collagenase-digested fat tissues. Total and visceral adiposity were assessed by dual-energy X-ray absorptiometry and computed tomography, respectively. Serum 25(OH)D was measured by radioimmmunoassay. Dietary intakes were assessed using a food frequency questionnaire. Women consuming two or more dairy product portions daily had smaller adipocytes in the omental depot compared to women consuming less than two portions daily (79 ± 12 vs. 94 ± 16 µm, P ≤ 0.01). Dietary intakes of calcium (r = -0.55) and vitamin D (r = -0.43) as well as serum 25(OH)D (r = -0.35) were also inversely and significantly associated with omental adipocyte size (P ≤ 0.05 for all). Dietary vitamin D intake was inversely associated with visceral adipose tissue area (r = -0.34, P ≤ 0.05). Serum 25(OH)D was also inversely associated with visceral adipose tissue area (r = -0.32) as well as with total adipose tissue area (r = -0.44), subcutaneous adipose tissue area (r = -0.36), BMI (r =-0.43) and total body fat mass (r = -0.41, P ≤ 0.05 for all). In conclusion, elevated dietary vitamin D intake and serum 25(OH)D values are related to lower visceral adiposity and omental adipocyte size in women.

The glucocorticoid contribution to obesity

Obesity is fast becoming the scourge of our time. It is one of the biggest causes of death and disease in the industrialized world, and affects as many as 32% of adults and 17% of children in the USA, considered one of the world's fattest nations. It can also cost countries billions of dollars per annum in direct and indirect care, latest estimates putting the USA bill for obesity-related costs at $147 billion in 2008. It is becoming clear that the pathophysiology of obesity is vastly more complicated than the simple equation of energy in minus energy out. A combination of genetics, sex, perinatal environment and life-style factors can influence diet and energy metabolism. In this regard, psychological stress can have significant long-term impact upon the propensity to gain and maintain weight. In this review, we will discuss the ability of psychological stress and ultimately glucocorticoids (GCs) to alter appetite regulation and metabolism. We will specifically focus on (i) GC regulation of appetite and adiposity, (ii) the apparent sexual dimorphism in stress effects on obesity and (iii) the ability of early life stress to programme obesity in the long term.

Expression of 11β-hydroxysteroid dehydrogenase type 1 in visceral and subcutaneous adipose tissues of patients with polycystic ovary syndrome is associated with adiposity

Polycystic ovary syndrome (PCOS) is characterized by insulin resistance (IR) and central obesity. The impact of adipose tissue cortisol reactivation by 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) on markers of obesity and IR was assessed in PCOS patients. Eighty-five PCOS patients and 43 controls were enrolled for subcutaneous adipose tissue biopsy; 25/85 patients and 29/43 controls underwent also visceral adipose tissue biopsy. HSD11B1 gene expression and expression of lipid metabolism genes were measured in subcutaneous and visceral adipose tissues. Anthropometric and biochemical markers of IR and PCOS were also assessed. HSD11B1 expression in visceral and subcutaneous adipose tissue was increased in PCOS patients compared to controls (p<0.05). After BMI adjustment, the difference was no longer significant. In PCOS patients, visceral HSD11B1 expression correlated positively with waist circumference (p=0.001), BMI (p=0.002), plasma insulin (p<0.05), systolic blood pressure (p=0.003), and lipoprotein lipase (LPL), hormone-sensitive lipase (LIPE) and peroxisome-proliferator activated receptor γ gene expression. Subcutaneous HSD11B1 expression correlated positively with BMI, waist circumference (p<0.001 for both) and HOMA-IR (p=0.003), and negatively with LPL, LIPE, adiponectin and glucose transporter GLUT4 gene expression. HSD11B1 expression in both depots showed a negative correlation with plasma HDL-cholesterol (p<0.03) and a positive one with C-reactive protein (p<0.001). In multiple regression analysis, HSD11B1 expression in visceral adipose tissue was most prominently associated with waist circumference, and that in subcutaneous adipose tissue with BMI (p<0.001 for both). Our results show that PCOS is not associated with increased HSD11B1 expression once adiposity is controlled for. Increased expression of this gene correlates with markers of adiposity and predicts IR and an unfavorable metabolic profile, independently of PCOS.

Inhibitors of 11β-hydroxysteroid dehydrogenase type 1 in antidiabetic therapy

Glucocorticoid action is mediated by glucocorticoid receptor (GR), which upon cortisol binding is activated and regulates the transcriptional expression of target genes and downstream physiological functions. 11β-Hydroxysteroid dehydrogenase type 1 (11β-HSD1) catalyzes the conversion of inactive cortisone to active cortisol. Since cortisol is also produced through biosynthesis in the adrenal glands, the total cortisol level in a given tissue is determined by both the circulating cortisol concentration and the local 11β-HSD1 activity. 11β-HSD1 is expressed in liver, adipose, brain, and placenta. Since it contributes to the local cortisol levels in these tissues, 11β-HSD1 plays a critical role in glucocorticoid action. The metabolic symptoms caused by glucocorticoid excess in Cushing's syndrome overlap with the characteristics of the metabolic syndrome, suggesting that increased glucocorticoid activity may play a role in the etiology of the metabolic syndrome. Consistent with this notion, elevated adipose expression of 11β-HSD1 induced metabolic syndrome-like phenotypes in mice. Thus, 11β-HSD1 is a proposed therapeutic target to normalize glucocorticoid excess in a tissue-specific manner and mitigate obesity and insulin resistance. Selective inhibitors of 11β-HSD1 are under development for the treatment of type 2 diabetes and other components of the metabolic syndrome.

Cerebrospinal fluid corticosteroid levels and cortisol metabolism in patients with idiopathic intracranial hypertension: a link between 11beta-HSD1 and intracranial pressure regulation?

CONTEXT

The etiology of idiopathic intracranial hypertension (IIH) is unknown. We hypothesized that obesity and elevated intracranial pressure may be linked through increased 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) activity.

OBJECTIVE

The aim was to characterize 11β-HSD1 in human cerebrospinal fluid (CSF) secretory [choroid plexus (CP)] and drainage [arachnoid granulation tissue (AGT)] structures, and to evaluate 11β-HSD1 activity after therapeutic weight loss in IIH.

DESIGN AND SETTING

We conducted in vitro analysis of CP and AGT and a prospective in vivo cohort study set in two tertiary care centers.

PATIENTS OR OTHER PARTICIPANTS

Twenty-five obese adult female patients with active IIH were studied, and 22 completed the study.

INTERVENTION

Fasted serum, CSF, and 24-h urine samples were collected at baseline, after 3-month observation, and after a 3-month diet.

MAIN OUTCOME MEASURES

Changes in urine, serum, and CSF glucocorticoids (measured by gas chromatography/mass spectrometry and liquid chromatography/tandem mass spectrometry) after weight loss were measured.

RESULTS

11β-HSD1 and key elements of the glucocorticoid signaling pathway were expressed in CP and AGT. After weight loss (14.2±7.8 kg; P<0.001), global 11β-HSD1 activity decreased (P=0.001) and correlated with reduction in intracranial pressure (r=0.504; P=0.028). CSF and serum glucocorticoids remained stable, although the change in CSF cortisone levels correlated with weight loss (r=-0.512; P=0.018).

CONCLUSIONS

Therapeutic weight loss in IIH is associated with a reduction in global 11β-HSD1 activity. Elevated 11β-HSD1 may represent a pathogenic mechanism in IIH, potentially via manipulation of CSF dynamics at the CP and AGT. Although further clarification of the functional role of 11β-HSD1 in IIH is needed, our results suggest that 11β-HSD1 inhibition may have therapeutic potential in IIH.