Effects of Carbenoxolone on the Canine Pituitary-Adrenal Axis

Cushing’s disease caused by pituitary corticotroph adenoma is a common endocrine disease in dogs. A characteristic biochemical feature of corticotroph adenomas is their relative resistance to suppressive negative feedback by glucocorticoids. The abnormal expression of 11beta-hydroxysteroid dehydrogenase (11HSD), which is a cortisol metabolic enzyme, is found in human and murine corticotroph adenomas. Our recent studies demonstrated that canine corticotroph adenomas also have abnormal expression of 11HSD. 11HSD has two isoforms in dogs, 11HSD type1 (HSD11B1), which converts cortisone into active cortisol, and 11HSD type2 (HSD11B2), which converts cortisol into inactive cortisone. It has been suggested that glucocorticoid resistance in corticotroph tumors is related to the overexpression of HSD11B2. Therefore it was our aim to investigate the effects of carbenoxolone (CBX), an 11HSD inhibitor, on the healthy dog’s pituitary-adrenal axis. Dogs were administered 50 mg/kg of CBX twice each day for 15 days. During CBX administration, no adverse effects were observed in any dogs. The plasma adrenocorticotropic hormone (ACTH), and serum cortisol and cortisone concentrations were significantly lower at day 7 and 15 following corticotropin releasing hormone stimulation. After completion of CBX administration, the HSD11B1 mRNA expression was higher, and HSD11B2 mRNA expression was significantly lower in the pituitaries. Moreover, proopiomelanocortin mRNA expression was lower, and the ratio of ACTH-positive cells in the anterior pituitary was also significantly lower after CBX treatment. In adrenal glands treated with CBX, HSD11B1 and HSD11B2 mRNA expression were both lower compared to normal canine adrenal glands. The results of this study suggested that CBX inhibits ACTH secretion from pituitary due to altered 11HSD expressions, and is potentially useful for the treatment of canine Cushing’s disease.     

Validation and application of a highly specific and sensitive ELISA for the estimation of cortisone in saliva, urine and in vitro cell-culture media by using a novel antibody

It is generally acknowledged that local tissue concentrations of cortisol and cortisone are modulated by site-specific actions of 11β-hydroxysteroid dehydrogenase (11β-HSD) isoenzymes 1 and 2. Cortisone, the inactive metabolite of cortisol is produced by 11βHSD type 2. To assess 11β-HSD types 1 and 2 activities, the cortisol/cortisone ratio has to be accurately determined. Immunoassays to measure cortisone levels are not widely available and tend to lack specificity. The aim of this project was to develop a highly specific and sensitive ELISA method for the estimation of free cortisone levels in urine, saliva and in vitro media samples without chromatographic separation. Antibodies against cortisone were raised in rabbits using cortisone-3-CMO-KLH as immunogen. HRP-goat anti-rabbit IgG conjugate was used as enzyme tracer. Cross-reactivities of the untreated cortisone antiserum with major interfering steroids were minimal except for cortisol (3.15%). However, following an immune-affinity purification of the antibodies using CNBr-activated sepharose-cortisol-3-CMO-BSA, cross-reactivity of the purified cortisone antibody with cortisol was reduced to 0.27%. The minimum detection limit of cortisone ELISA was 28 pg/mL (77.7 pM). The validity of the cortisone ELISA was confirmed by the excellent correlation obtained before and after an HPLC fractionation step (Y=1.09X-0.21, R2=0.98). Intra-assay and inter-assay imprecision were 5.5-11.7% and 8.7-12.8% CV, respectively. Using this assay, salivary cortisone levels showed a circadian rhythm in men and women (11.2±7.3 nM at 08.00 h and 5.1±3.6 nM at 18.00 h), and the levels were reduced following liquorice ingestion. In media of adrenocortical H295 cell line incubations, basal cortisone levels were 4.24±0.22 nM that increased to 8.6±1.2 nM post forskolin treatment. Urinary free cortisone excretion levels in healthy subjects were 56.66±36.9 nmol/day. In human volunteers following ingestion of green coffee bean extract for 2 weeks, urinary free cortisol excretion reduced significantly from 66.67±22.3 to 42.66±17.5 nmol/day (p=0.02) and the cortisol/cortisone ratio from 2.04±1.33 to 1.49±1.13, p=0.05. In conclusion, a simple and highly specific and sensitive ELISA has been developed and applied to estimate cortisone levels in biological fluids and culture media.     

Gender-specific links between hepatic 11beta reduction of cortisone and adipokines

Objective: Reduction of cortisone to cortisol is mediated by 11β‐hydroxysteroid dehydrogenase type 1 (11βHSD1), a putative key enzyme in obesity‐related complications. Experimental studies suggest that adipokines, notably leptin and tumor necrosis factor‐α (TNF‐α), are of importance for 11βHSD1 activity. We hypothesized that the regulation of hepatic preceptor glucocorticoid metabolism is gender‐specific and associated with circulating levels of leptin and TNF‐α receptors and/or sex hormones. Research Methods and Procedures: A total of 34 males and 38 women (14 premenopausal and 22 postmenopausal) underwent physical examination and fasting blood sampling. Insulin sensitivity was tested by euglycemic hyperinsulinemic clamps, and hepatic 11βHSD1 enzyme activity was estimated by the conversion of orally‐ingested cortisone to cortisol. Results: Hepatic 11βHSD1 activity was negatively associated with leptin and soluble TNF (sTNF) r1 and sTNFr2 in males. These correlations remained significant after adjustment for age and insulin sensitivity, and for sTNF‐α receptors also after adjustment of BMI and waist circumference. In contrast, 11β reduction of cortisone was positively associated to leptin in females after adjustment for BMI and waist circumference. Discussion: Hepatic 11β reduction shows different links to circulating adipocyte‐derived hormones in males and females. This emphasizes the need for further studies on tissue‐specific regulation of 11βHSD1 in both genders.     

Keratinocytes synthesize and activate cortisol

The bioavailability of circulating and/or endogenous hydrocortisone (cortisol) in epidermal cells is a key determinant in inflammatory disease and chronic wounds. It is not known, however, whether epidermal cells can regulate tissue cortisol and whether they are capable of producing endogenous glucocorticoids. In the present study, we show by microarray analysis that epidermal cells express mRNAs to all the major enzymes involved in the metabolic chain from cholesterol to cortisol, including cytocrome P450 chain, 11β-hydroxysteroid dehydrogenases (HSD11Bs), adrenocorticotropic hormone (ACTH) receptor (MC2R), and glucocorticoid receptor. The two enzymes mediating activation/deactivation of cortisone to cortisol, namely HSD11B1 and HSD11B2, were expressed at the protein level in cultured keratinocytes as well as human skin samples, as shown by Western blotting and immunohistochemistry, respectively. In functional assays, we show that keratinocytes are not only able to activate cortisone to cortisol in a HSD11B-dependent manner but also silencing of either HSD11B1 or HSD11B2 specifically modulates the bioavailability of the inactive glucocorticoid and the active steroid, respectively. A further key observation was that keratinocytes responded to stimulation with ACTH by a significant increase in the de novo synthesis of cortisol. Taken together, we provide evidence for a novel non-adrenal steroideal system in human keratinocytes.     

Effect of glycyrrhizine on hyperkalemia due to hyporeninemic hypoaldosteronism in diabetes mellitus

Liquorice extract has been claimed to induce inhibition of the activity of 11β-hydroxysteroid dehydrogenase which converts cortisol to cortisone. This enzyme is thought to protect the mineralocorticoid receptor from being occupied by endogeneous glucocorticoids in the kidney. Based on these hypotheses, we investigated the effect of low-dose glycyrrhizine on hyperkalemia due to hyporeninemic hypoaldosteronism in eight subjects with NIDDM. The mean serum potassium concentration decreased from 5.3 ± 0.3 (SD) mEq/1 to 4.9 ± 0.2 mEq/1 when 15 g of calcium polystyrene sulfonate, a potassium-binding resin, was given per day, and it decreased significantly to 4.4 ± 0.4 mEq/1 with 150 mg/day of glycyrrhizine therapy. Changes in fasting plasma glucose and hemoglobin A_1C were not significant. These data support the assumption that liquorice extract can be used safely in the therapy for treating hyperkalemia due to selective hypoaldosteronism in diabetes mellitus subjects.     

N-(Pyridin-2-yl) arylsulfonamide inhibitors of 11β-hydroxysteroid dehydrogenase type 1: Discovery of PF-915275

N-(Pyridin-2-yl) arylsulfonamides are identified as inhibitors of 11β-hydroxysteroid dehydrogenase type 1 (11βHSD1), an enzyme that catalyzes the reduction of the glucocorticoid cortisone to cortisol. Dysregulation of glucocorticoids has been implicated in the pathogenesis of diabetes and the metabolic syndrome. In this Letter, we present the development of an initial lead to an efficient ligand with improved physiochemical properties using a deletion strategy. This strategy allowed for further optimization of potency leading to the discovery of the clinical candidate PF-915275.     

Differential expression of placental 11β-hydroxysteroid dehydrogenases in pregnant women with diet-treated gestational diabetes mellitus

Fetal exposure to excess glucocorticoid is one of the critical factors for the fetal origins of adult diseases. However, the mechanism of the local regulation of glucocorticoid activity in the human placenta of pregnancies complicated with gestational diabetes mellitus (GDM) has not been fully understood. We investigated placental 11β-hydroxysteroid dehydrogenases (11β-HSDs) expression, and analyzed their relationship with cortisol levels in maternal and umbilical vein. Pregnant women with GDM after diet intervention (n=23) or normal glucose tolerance (NGT, n=22) were studied at the community-based hospital. We collected maternal and umbilical venous cord blood and placental tissues from both groups. Explanted placentas from NGT were cultured with palmitic acid, dexamethasone, insulin or their mixture for 24-h. We examined plasma cortisol, cortisone to cortisol ratio, insulin, the homeostasis model assessment of insulin resistance index (HOMA-IR) and the insulin secretion index. Quantitative real-time PCR, Western blot and immunohistochemical assay were applied for the measurement of 11β-HSD1 and 11β-HSD2 mRNA and protein. GDM had higher maternal cortisol levels, HOMA-IR, insulin secretion index and higher cortisone to cortisol ratio in umbilical vein. No significant change in cortisol levels in umbilical vein and newborn weight was found. GDM placental 11β-HSD1 levels decreased while 11β-HSD2 increased. Treatment of placenta explants from NGT with palmitic acid, dexamethasone, insulin or their combination resulted in a significant drop of 11β-HSD1 and increase in 11β-HSD2. Differential expression of 11β-HSDs in diet-treated GDM placenta provides a protective mechanism for the fetus throughout the adverse environment of pregnancy by limiting excessive exposure of the fetus to glucocorticoid.     

Regulation of glucocorticoid metabolism in the boar testis and caput epididymidis by the gonadotrophin-cAMP signalling pathway

In target tissues, cortisol is metabolised by two 11β-hydroxysteroid dehydrogenase (11βHSD) isoenzymes, namely 11βHSD1 and 11βHSD2, both of which are co-expressed in the boar testis and reproductive tract. The present study has assessed whether cortisol-cortisone metabolism in boar testis and caput epididymidis can be regulated via the gonadotrophin-cAMP signalling pathway. 11βHSD activities were measured by using a radiometric conversion assay in static tissue culture. In both testis and caput epididymidis, the net reduction of cortisone but not the net oxidation of cortisol, was significantly decreased by luteinising hormone (by 53?±?20% and 45?±?9%, respectively, P?<?0.05), forskolin (by 60?±?7% and 57?±?9%, respectively, P?<?0.01) and 8-bromo-cAMP (by 54?±?4% and 64?±?1%, respectively, P?<?0.01). This suppression of 11-ketosteroid reductase activity in the boar testis by forskolin could be attenuated by the protein kinase A (PKA) inhibitor, H89. Hence, within the boar testis and the caput epididymidis, the local actions of glucocorticoids are modulated by gonadotrophin-cAMP-PKA signalling via their selective effects on the reductase activity of 11βHSD.     

Effects of antisense-mediated inhibition of 11β-hydroxysteroid dehydrogenase type 1 on hepatic lipid metabolism

11β-hydroxysteroid dehydrogenase 1 (11β-HSD1) converts inactive 11-keto derivatives to active glucocorticoids within tissues and may play a role in the metabolic syndrome (MS). We used an antisense oligonucleotide (ASO) to knock down 11β-HSD1 in livers of C57BL/6J mice consuming a Western-type diet (WTD). 11β-HSD1 ASO-treated mice consumed less food, so we compared them to ad libitum-fed mice and to food-matched mice receiving control ASO. Knockdown of 11β-HSD1 directly protected mice from WTD-induced steatosis and dyslipidemia by reducing synthesis and secretion of triglyceride (TG) and increasing hepatic fatty acid oxidation. These changes in hepatic and plasma lipids were not associated with reductions in genes involved in de novo lipogenesis. However, protein levels of both sterol regulatory element-binding protein (SREBP) 1 and fatty acid synthase were significantly reduced in mice treated with 11β-HSD1 ASO. There was no change in hepatic secretion of apolipoprotein (apo)B, indicating assembly and secretion of smaller apoB-containing lipoproteins by the liver in the 11β-HSD1-treated mice. Our results indicate that inhibition of 11β-HSD1 by ASO treatment of WTD-fed mice resulted in improved plasma and hepatic lipid levels, reduced lipogenesis by posttranslational regulation, and secretion of similar numbers of apoB-containing lipoproteins containing less TG per particle.     

The role of 11β-hydroxysteroid dehydrogenase type 2 in human hypertension

Cortisol and aldosterone have the same in vitro affinity for the mineralocorticoid receptor (MR), although in vivo only aldosterone acts as a physiologic agonist of the MR, despite circulating levels of cortisol in humans and corticosterone in rodents being three orders of magnitude higher than aldosterone levels. In mineralocorticoid target organs the enzyme 11β-hydroxysteroid dehydrogenase type 2 (11βHSD2) inactivates 11-hydroxy steroids, to their inactive keto-forms, thus protecting the nonselective MR from activation by glucocorticoids. The gene is highly expressed in all sodium-transporting epithelia, particularly in the kidney and colon, but also in human placenta and vascular wall. Mutations in the HSD11B2 gene cause a rare monogenic juvenile hypertensive syndrome called apparent mineralocorticoid excess (AME). In AME, compromised 11βHSD2 enzyme activity results in activation of the MR by cortisol, causing sodium retention, hypokalaemia, and salt-dependent hypertension. Whereas mutations or inhibition of 11βHSD2 by licorice have been clearly shown to produce a congenital or acquired syndrome of mineralocorticoid excess, the questions remaining are the extent to which subtle abnormalities in MR/11βHSD2 mechanisms may contribute to essential hypertension. Studies in patients with essential hypertension showed a prolonged half-life of cortisol and an increased ratio of urinary cortisol to cortisone metabolites, suggesting a deficient 11βHSD2 activity. These abnormalities may be genetically determined, as suggested by the association of a microsatellite flanking the HSD11B2 gene with hypertension in black patients with end-stage kidney disease and with salt sensitivity of blood pressure in healthy subjects. These findings indicate that variants of the HSD11B2 gene may contribute to the enhanced blood pressure response to salt and possibly to hypertension in humans.     

Tissue-Specific Increases in 11β-Hydroxysteroid Dehydrogenase Type 1 in Normal Weight Postmenopausal Women

With age and menopause there is a shift in adipose distribution from gluteo-femoral to abdominal depots in women. Associated with this redistribution of fat are increased risks of type 2 diabetes and cardiovascular disease. Glucocorticoids influence body composition, and 11β-hydroxysteroid dehydrogenase type 1 (11βHSD1) which converts inert cortisone to active cortisol is a putative key mediator of metabolic complications in obesity. Increased 11βHSD1 in adipose tissue may contribute to postmenopausal central obesity. We hypothesized that tissue-specific 11βHSD1 gene expression and activity are up-regulated in the older, postmenopausal women compared to young, premenopausal women. Twenty-three pre- and 23 postmenopausal, healthy, normal weight women were recruited. The participants underwent a urine collection, a subcutaneous adipose tissue biopsy and the hepatic 11βHSD1 activity was estimated by the serum cortisol response after an oral dose of cortisone. Urinary (5α-tetrahydrocortisol+5β-tetrahydrocortisol)/tetrahydrocortisone ratios were higher in postmenopausal women versus premenopausal women in luteal phase (P<0.05), indicating an increased whole-body 11βHSD1 activity. Postmenopausal women had higher 11βHSD1 gene expression in subcutaneous fat (P<0.05). Hepatic first pass conversion of oral cortisone to cortisol was also increased in postmenopausal women versus premenopausal women in follicular phase of the menstrual cycle (P<0.01, at 30 min post cortisone ingestion), suggesting higher hepatic 11βHSD1 activity. In conclusion, our results indicate that postmenopausal normal weight women have increased 11βHSD1 activity in adipose tissue and liver. This may contribute to metabolic dysfunctions with menopause and ageing in women.     

Cortisone induces insulin resistance in C2C12 myotubes through activation of 11beta‐hydroxysteroid dehydrogenase 1 and autocrinal regulation

The enzyme 11β‐hydroxysteroid dehydrogenase 1 (11β‐HSD1) is known to catalyse inactive glucocorticoids into active forms, and its dysregulation in adipose and muscle tissues has been implicated in the development of metabolic syndrome. To delineate the molecular mechanism by which active cortisol has an antagonizing effect against insulin, we optimized the metabolic production of cortisol and its biological functions in myotubes (C2C12). Myotubes supplemented with cortisone actively catalysed its conversion into cortisol, which in turn abolished phosphorylation of Akt in response to insulin treatment. This led to diminished uptake of insulin‐induced glucose. This was corroborated by the application of 11β‐HSD1 inhibitor glycyrrhetinic acid and a glucocorticoid receptor antagonist RU‐486, which reversed completely the antagonizing effects of cortisol on insulin action. Therefore, development of specific inhibitors targeting 11β‐HSD1 might be a promising way to improve impaired insulin‐stimulated glucose uptake. Copyright © 2013 John Wiley & Sons, Ltd.     

Prolonged fasting in mice: a more sensitive approach to genetic diabetes.

Effects of two different periods of fasting were studied on glucose tolerance and insulin response to glucose in genetically diabetic KK and nondiabetic C57BL/6J mice. Blood sugar levels of the KK mice did not differ markedly from those of the C57BL/6J mice at the fed state or after 8 h fasting. They were, however, significantly higher in the KK mice when fasted for 18 h. The serum IRI levels, which were at least twice as high in the KK mice, decreased more markedly after 18 h fasting. The KK mice showed impaired glucose tolerance after 8 h fasting, which became more pronounced after 18 h fasting. The insulin response to glucose in the KK mice was not altered after an 8-hour fast; it was, however, diminished greatly after an 18-hour fast. These data suggest that prolonged fasting is necessary to detect the diabetic traits in the KK mice. The C57BL/6J mice showed neither impaired glucose tolerance nor diminished insulin response to glucose at both periods of fasting. Studies with the F1 hybrids (KK male X C57BL/6J female), which carry half of the diabetic genes, suggest that the mode of inheritance of diabetes in the KK mice might be polygenic.     

Changes in relationship between blood glucose level and plasma 1,5-anhydroglucitol level in KK mice

We compared the relationship of the blood glucose level to the plasma 1,5-anhydroglucitol (1,5AG) level between KK mice with abnormal glucose metabolism and ICR mice as controls. Although the plasma 1,5AG level did not show any significant correlation with the blood glucose level in the controls, it tended to logarithmically decrease with the rise in the blood glucose level in KK mice. Thus it is possible that the plasma 1,5AG level is specifically related to the abnormal glucose metabolism in this model of diabetes mellitus and that its routine examination in diabetic patients may help delineate the metabolic derangement in the disease.     

Synthesis of the N‐methyl Derivatives of 2‐Aminothiazol‐4(5H)‐one and Their Interactions with 11βHSD1‐Molecular Modeling and in Vitro Studies

11β‐Hydroxysteroid dehydrogenase type 1 (11β‐HSD1) is an enzyme that affects the body's cortisol levels. The inhibition of its activity can be used in the treatment of Cushing's syndrome, metabolic syndrome and type 2 diabetes. In this study, we synthesized new derivatives of 2‐(methylamino)thiazol‐4(5H)‐one and tested their activity towards inhibition of 11β‐HSD1 and its isoform – 11β‐HSD2. The results were compared with the previously tested allyl derivatives. We found out that methyl derivatives are weaker inhibitors of 11β‐HSD1 in comparison to their allyl analogs. Due to significant differences in the activity of the compounds, molecular modeling was performed, which was aimed at comparing the interactions between 11β‐HSD1 and ligands differing by substituent at the amine group (allyl vs. methyl). Modeling showed that the absence of the allyl group can lead to the rotation of whole ligand molecule which affects its interaction with the enzyme.     

11Beta-hydroxysteroid dehydrogenase type 2 and the regulation of surfactant protein A by dexamethasone metabolites

Glucocorticoid (GC) metabolism by the 11beta-hydroxysteroid dehydrogenase (HSD) system is an important prereceptor regulator of GC action. The HSD enzymes catalyze the interconversion of the endogenous, biologically active GC cortisol and its inactive 11-dehydro metabolite cortisone. The role of the HSD enzymes in the metabolism of synthetic GCs, such as dexamethasone (Dex), is more complex. The human lung is a classic GC-sensitive organ; however, the roles of the HSD enzymes (HSD1 and HSD2) in the human lung are poorly understood. In the present study, we examined the expression of the HSD enzymes in human adult and fetal lung tissues and the human lung epithelial cell line NCI-H441. We observed that human adult and fetal lung tissues, as well as H441 cells, express HSD2 protein and that it is upregulated by Dex (10(-7) M). By contrast, HSD1 protein was undetectable. We also show that the Dex-mediated regulation of surfactant protein A is attenuated by inhibition of HSD2 activity. Furthermore, we demonstrate that unlike the inactive, 11-dehydro metabolite of cortisol (i.e., cortisone), the 11-dehydro metabolite of Dex, 11-dehydro-Dex, competes for binding to the GC receptor (GR) in human lung epithelial cells and retains GR agonist activity. Together, these data suggest that differences exist in the biological activities of the metabolites of cortisol and Dex.     

Beneficial Metabolic Effects of CB1R Anti-Sense Oligonucleotide Treatment in Diet-Induced Obese AKR/J Mice

An increasing amount of evidence supports pleiotropic metabolic roles of the cannibinoid-1 receptor (CB1R) in peripheral tissues such as adipose, liver, skeletal muscle and pancreas. To further understand the metabolic consequences of specific blockade of CB1R function in peripheral tissues, we performed a 10-week-study with an anti-sense oligonucleotide directed against the CB1R in diet-induced obese (DIO) AKR/J mice. DIO AKR/J mice were treated with CB1R ASO Isis-414930 (6.25, 12.5 and 25 mg/kg/week) or control ASO Isis-141923 (25 mg/kg/week) via intraperitoneal injection for 10 weeks. At the end of the treatment, CB1R mRNA from the 25 mg/kg/week CB1R ASO group in the epididymal fat and kidney was decreased by 81% and 63%, respectively. Body weight gain was decreased in a dose-dependent fashion, significantly different in the 25 mg/kg/week CB1R ASO group (46.1±1.0 g vs veh, 51.2±0.9 g, p<0.05). Body fat mass was reduced in parallel with attenuated body weight gain. CB1R ASO treatment led to decreased fed glucose level (at week 8, 25 mg/kg/week group, 145±4 mg/dL vs veh, 195±10 mg/dL, p<0.05). Moreover, CB1R ASO treatment dose-dependently improved glucose excursion during an oral glucose tolerance test, whereas control ASO exerted no effect. Liver steatosis was also decreased upon CB1R ASO treatment. At the end of the study, plasma insulin and leptin levels were significantly reduced by 25 mg/kg/week CB1R ASO treatment. SREBP1 mRNA expression was decreased in both epididymal fat and liver. G6PC and fatty acid translocase/CD36 mRNA levels were also reduced in the liver. In summary, CB1R ASO treatment in DIO AKR/J mice led to improved insulin sensitivity and glucose homeostasis. The beneficial effects of CB1R ASO treatment strongly support the notion that selective inhibition of the peripheral CB1R, without blockade of central CB1R, may serve as an effective approach for treating type II diabetes, obesity and the metabolic syndrome.     

Pulmonary phospholipied biosynthesis and the ability of the fetal rabbit lung to reduce cortisone to cortisol during the final ten days of gestation

Incubation of fetal lung tissue with 0.2 μM ¹⁴C-cortisone revealed a 12-fold increase in the rate of reduction of cortisone to cortisol between day 22 and day 30 of gestation in the rabbit. This increase correlated closely with the increase in the rate of incorporation of ¹⁴C-choline into total lung lipids during the same period. In light of these findings it would seem inadequate to attempt to relate the plasma cortisol concentration alone with the rate of lung maturation. In addition, one would need consider both the plasma concentration of cortisone and the activity of 11β-hydroxysteroid dehydrogenase (11β-HSD) in the lung.     

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.