11ß-hydroxysteroid dehydrogenases: A growing multi-tasking family.

This review briefly addresses the history of the discovery and elucidation of the three cloned 11ß-hydroxysteroid dehydrogenase (11ßHSD) enzymes in the human, 11ßHSD1, 11ßHSD2 and 11ßHSD3, an NADP+-dependent dehydrogenase also called the 11ßHSD1-like dehydrogenase (11ßHSD1L), as well as evidence for yet identified 11ßHSDs. Attention is devoted to more recently described aspects of this multi-functional family. The importance of 11ßHSD substrates other than glucocorticoids including bile acids, 7-keto sterols, neurosteroids, and xenobiotics is discussed, along with examples of pathology when functions of these multi-tasking enzymes are disrupted. 11ßHSDs modulate the intracellular concentration of glucocorticoids, thereby regulating the activation of the glucocorticoid and mineralocorticoid receptors, and 7ß-27-hydroxycholesterol, an agonist of the retinoid-related orphan receptor gamma (RORγ). Key functions of this nuclear transcription factor include regulation of immune cell differentiation, cytokine production and inflammation at the cell level. 11ßHSD1 expression and/or glucocorticoid reductase activity are inappropriately increased with age and in obesity and metabolic syndrome (MetS). Potential causes for disappointing results of the clinical trials of selective inhibitors of 11ßHSD1 in the treatment of these disorders are discussed, as well as the potential for more targeted use of inhibitors of 11ßHSD1 and 11ßHSD2.

Comprehensive semisyntheses of catathelasmols C, D, and E from D-glutamic acid, utilizing lipase-catalyzed site-selective reactions on intermediates.

Catathelasmols C, D, and E, which had been isolated from Catathelasma imperiale as inhibitors for 11-hydroxysteroid dehydrogenases, were comprehensively semisynthesized from commercially available D-glutamic acid. The key synthetic intermediate, (R)-pentane-1,2,5-triol, was site-selectively acetylated by treatment with vinyl acetate and Candida antarctica lipase B (Novozym 435) in tetrahydrofuran (THF) at 25°C to furnish 1,5-diacetate (catathelasmol E, quantitative). The acetylation occurred site-selectively on the primary alcohols at the C-1 and C-5 positions over the secondary alcohol at the C-2 position. Dichromic acid oxidation provided 2-oxopentane-1,5-diyl diacetate (catathelasmol C, 78%). Burkholderia cepacia lipase-catalyzed transesterification with methanol in THF at - 5°C proceeded preferentially on the acetate at C-1 located adjacent to the C-2 carbonyl group over the other terminal acetate at the C-5 position. 5-Hydroxy-4-oxopentyl acetate (catathelasmol D) was obtained in 53% yield.

A new tremulane sesquiterpenoid from the fungus Irpex lacteus.

A new tremulane sesquiterpenoid, named irlactam A (1), was isolated from cultures of the fungus Irpex lacteus. The new structure was elucidated by spectroscopic data analysis. The compound was tested for its cytotoxicities on HL-60, SMMC-7721, A-549, MCF-7, and SW480 cells and for its inhibitory activity against isozymes of 11 ß-hydroxysteroid dehydrogenases (11 ß-HSD).

A new guaiane sesquiterpene from cultures of the fungus Fulvifomes kanehirae.

A new guaiane sesquiterpene (1) was isolated from cultures of the fungus Fulvifomes kanehirae. Its structure was elucidated by spectroscopic methods including extensive 2D-NMR techniques. Meanwhile, the compound was tested for its inhibitory activity against isozymes of 11ß-hydroxysteroid dehydrogenases (11ß-HSD).

Harnessing the gatekeepers of glucocorticoids for chemoprevention of non-melanoma skin cancer.

Despite effective surgical methods for non-melanoma skin cancer (NMSC), patients suffer from tissue damage, scarring, or even disfigurement; thus, there is a need for chemopreventive approaches. Because of the complex interplay between glucocorticoids (GCs), inflammation, and cancer, we sought to determine the role of 11ß-hydroxysteroid dehydrogenase 1 and 2 (11ßHSD1 and 2) in regulating GCs during skin cancer development and progression. 11ßHSDs modulate the activation of GCs in a tissue-specific manner and have been reported to play a role in development and progression of other types of cancer, but their role has not yet been reported in NMSC. Here, we found a significant upregulation of 11ßHSD2 protein in skin cancer cells when compared to normal skin cells, suggesting a role for this enzyme in the multifactorial process of skin cancer development. In addition, inhibition of 11ßHSD2 with siRNA resulted in significant reduction in colony formation in vitro. Finally, our in vivo study elucidated that inhibition of 11ßHSD2 with pharmacological inhibitor, Glycyrrhetinic acid (GA) could significantly diminish tumorigenesis in a well-studied in vivo mouse model of NMSC. Overall, these studies highlight for the first time a potential novel role for 11ßHSD2 in NMSC development and may allow for new GC treatment approaches capable of avoiding deactivation by the enzyme. If 11ßHSD2 can be inhibited as we have done here, or circumvented using modified GCs, this may lead to more efficacious outcomes for NMSC patients by preventing deactivation of the GC and minimizing resistance.

Thiazolo[3,2-a]pyrimidin-5-one derivatives as a novel class of 11ß-hydroxysteroid dehydrogenase inhibitors.

11ß-hydroxysteroid type 1 dehydrogenase (11ß-HSD1) is an enzyme that increases tissue concentrations of cortisol. Selective inhibitors of this enzyme regulate the level of cortisol and thus play a key role in the treatment of Cushing's syndrome, metabolic syndrome and type 2 diabetes. In this study the inhibitory activity of 29 thiazolo[3,2-a]pyrimidin-5-one derivatives on 11ß-HSD1 were investigated. Studies were carried out with pooled human liver microsomes. A lot of analyzed compounds show activity for inhibiting 11ß-HSD1 (up to 59.15% at concentration 10 µmol/l). Molecular docking simulation show that the molecule of the most active compound: 7-(cyclohexylmethyl)-2-iodomethyl-2,3-dihydrothiazolo[3,2-a]pyrimidin-5-one forms hydrogen bonds with Ala172, Leu171, Leu215 or Tyr177. In addition, the cycloalkane moiety can create the hydrophobic contacts with NADP+. For this compound also the most favourable Docking Score value was obtained. The most active compound only in the slight degree inhibits 11ß-HSD2 activity and is a selective inhibitor of 11ß-hydroxysteroid dehydrogenase type 1. Consequently it can have a real effect on the regulation of the cortisol level in the body.

A new cadinane sesquiterpenoid from cultures of the Basidiomycete Panus conchatus.

A new cadinane sesquiterpenoid, named panutorulon A (1), was isolated from cultures of the basidiomycete Panus conchatus. The new structure was elucidated by means of spectroscopic methods. Compound 1 was tested for its cytotoxicity against five human cancer cell lines and for its inhibitory activity against isozymes of 11ß-hydroxysteroid dehydrogenases (11ß-HSD).

11Beta-hydroxysteroid dehydrogenase-1 deficiency or inhibition enhances hepatic myofibroblast activation in murine liver fibrosis.

A hallmark of chronic liver injury is fibrosis, with accumulation of extracellular matrix orchestrated by activated hepatic stellate cells (HSCs). Glucocorticoids limit HSC activation in vitro, and tissue glucocorticoid levels are amplified by 11beta-hydroxysteroid dehydrogenase-1 (11ßHSD1). Although 11ßHSD1 inhibitors have been developed for type 2 diabetes mellitus and improve diet-induced fatty liver in various mouse models, effects on the progression and/or resolution of liver injury and consequent fibrosis have not been characterized. We have used the reversible carbon tetrachloride-induced model of hepatocyte injury and liver fibrosis to show that in two models of genetic 11ßHSD1 deficiency (global, Hsd11b1-/- , and hepatic myofibroblast-specific, Hsd11b1fl/fl /Pdgfrb-cre) 11ßHSD1 pharmacological inhibition in vivo exacerbates hepatic myofibroblast activation and liver fibrosis. In contrast, liver injury and fibrosis in hepatocyte-specific Hsd11b1fl/fl /albumin-cre mice did not differ from that of controls, ruling out 11ßHSD1 deficiency in hepatocytes as the cause of the increased fibrosis. In primary HSC culture, glucocorticoids inhibited expression of the key profibrotic genes Acta2 and Col1α1, an effect attenuated by the 11ßHSD1 inhibitor [4-(2-chlorophenyl-4-fluoro-1-piperidinyl][5-(1H-pyrazol-4-yl)-3-thienyl]-methanone. HSCs from Hsd11b1-/- and Hsd11b1fl/fl /Pdgfrb-cre mice expressed higher levels of Acta2 and Col1α1 and were correspondingly more potently activated. In vivo [4-(2-chlorophenyl-4-fluoro-1-piperidinyl][5-(1H-pyrazol-4-yl)-3-thienyl]-methanone administration prior to chemical injury recapitulated findings in Hsd11b1-/- mice, including greater fibrosis. CONCLUSION: 11ßHSD1 deficiency enhances myofibroblast activation and promotes initial fibrosis following chemical liver injury; hence, the effects of 11ßHSD1 inhibitors on liver injury and repair are likely to be context-dependent and deserve careful scrutiny as these compounds are developed for chronic diseases including metabolic syndrome and dementia. (Hepatology 2018;67:2167-2181).

Protostane-Type Triterpenoids from Alisma orientale.

Twenty-eight protostane triterpenoids, including a new degraded one (1), nine new ones (2 - 10), and two new natural ones (11 and 12), have been isolated from the dried rhizomes of Alisma orientale. Alisol R (1) was the first 20,21,22,23,24,25,26,27-octanorprotostane triterpenoid. The absolute configurations of 25-methoxyalisol F (2) and 16ß-hydroperoxyalisol B 23-acetate (3) were determined by X-ray diffraction analysis. In addition, alismaketone-B 23-acetate (28) showed potent vasorelaxant activity on endothelium-intact thoracic aorta rings precontracted with KCl.

11ß-hydroxysteroid dehydrogenases-2 decreases the apoptosis of MC3T3/MLO-Y4 cells induced by glucocorticoids.

The aim of the present study was to confirm the role of 11ß-hydroxysteroid dehydrogenases type 2(11ß-HSD-2) in steroid induced osteonecrosis of the femoral head(SANFH). We cultured mouse bone-like cells (MLO-Y4) and mouse osteoblast-like cells (MC3T3-E1). After overexpressed 11ß-HSD-2 successfully, we induced cell apoptosis by dexamethasone (DXM). The level of cell apoptosis, the expression of Bcl-2 in MLO-Y4 cells and the expression of Fas and caspase8 in MC3T3-E1 cells were detected. Then, we constructed 11ß-HSD-2 siRNA plasmid and represented it on MLO-Y4/MC3T3-E1 Cells, to down-regulate the 11ß-HSD-2 expression. After that, we used dexamethasone to induce cell apoptosis. The level of cell apoptosis, the expression of Bcl-2 in MLO-Y4 cells and the expression of Fas and caspase8 in MC3T3-E1 cells were detected again. In the overexpression model of cells, we found that the amount of cell apoptosis, the expression of Fas and caspase8 in MC3T3-E1 cells are lower than that of control groups. The amount of cell apoptosis, the expression of Fas and caspase8 in MC3T3-E1 cells were more than before when we reduced the expression of 11ß-HSD-2. In our study, we concluded that 11ß-HSD-2 plays an important role in the development of bone or osteoblast cell apoptosis, and the decreased expression of 11ß-HSD-2 may aggravate steroid induced bone/osteoblast cell apoptosis.

In Vivo 11ß-Hydroxysteroid Dehydrogenase Inhibition in Posaconazole-Induced Hypertension and Hypokalemia.

We describe a case of apparent mineralocorticoid excess (AME) secondary to posaconazole therapy and suggest the biochemical mechanism. Clinical and laboratory investigation confirmed 11ß-hydroxysteroid dehydrogenase inhibition and withholding therapy led to a resolution of all clinical and laboratory abnormalities. Posaconazole was later restarted at a lower dose and prevented recurrence of this syndrome. Additional studies are necessary to determine the frequency of posaconazole-induced AME and whether other azole antifungals can be associated with this phenomenon.

HPLC-ESI-MS/MS assessment of the tetrahydro-metabolites of cortisol and cortisone in bovine urine: promising markers of dexamethasone and prednisolone treatment.

The effects of long-term administration of low doses of dexamethasone (DX) and prednisolone (PL) on the metabolism of endogenous corticosteroids were investigated in veal calves. In addition to cortisol (F) and cortisone (E), whose interconversion is regulated by 11ß-hydroxysteroid dehydrogenases (11ßHSDs), special attention was paid to tetrahydrocortisol (THF), allo-tetrahydrocortisol (aTHF), tetrahydrocortisone (THE) and allo-tetrahydrocortisone (aTHE), which are produced from F and E by catalytic activity of 5α and 5ß-reductases. A specifically developed HPLC-ESI-MS/MS method achieved the complete chromatographic separation of two pairs of diastereoisomers (THF/aTHF and THE/aTHE), which, with appropriate mass fragmentation patterns, provided an unambiguous conformation. The method was linear (r(2) > 0.9905; 0.5-25 ng ml(-1)), with LOQQ of 0.5 ng ml(-1). Recoveries were in range 75-114%, while matrix effects were minimal. The experimental study was carried out on three groups of male Friesian veal calves: group PL (n = 6, PL acetate 15 mg day(-1) p.o. for 31 days); group DX (n = 5, 5 mg of estradiol (E2) i.m., weekly, and 0.4 mg day(-1) of DX p.o. for 31 days) and a control group (n = 8). Urine was collected before, during (twice) and at the end of treatment. During PL administration, the tetrahydro-metabolite levels decreased gradually and remained low after the suspension of treatment. DX reduced urinary THF that persisted after the treatment, while THE levels decreased during the experiment, but rebounded substantially after the DX was withdrawn. Both DX and PL significantly interfered with the production of F and E, leading to their complete depletion. Taken together, the results demonstrate the influence of DX and PL administration on 11ßHSD activity and their impact on dysfunction of the 5-reductase pathway. In conclusion, profiling tetrahydro-metabolites of F and E might serve as an alternative, indirect but reliable, non-invasive procedure for assessing the impact of synthetic glucocorticosteroids administration.

A validated enantioselective LC-MS/MS assay for quantification of a major chiral metabolite of an achiral 11-ß-hydroxysteroid-dehydrogenase 1 inhibitor in human plasma: Application to a clinical pharmacokinetic study.

BMS-823778 is a potent 11-ß-hydroxysteroid-dehydrogenase 1 (11ßHSD-1) inhibitor and a potential therapeutic agent for type 2 diabetes mellitus (T2DM). A high performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay was developed and validated to enable reliable separation and quantification of both enantiomers of a chiral hydroxy metabolite (BMT-094817) in human plasma. Following liquid-liquid extraction in a 96-well plate format, chromatographic separation of the metabolite enantiomers was achieved by isocratic elution on a Chiralpak IA-3 column. Chromatographic conditions were optimized to ensure separation of both metabolite enantiomers. Metabolite enantiomers and stable isotope-labeled (SIL) internal standards were detected by positive ion electrospray tandem mass spectrometry. The LC-MS/MS assay was validated over a concentration range of 0.200-200ng/mL. Intra- and inter-assay precision values for replicate quality control samples were less than 9.9% for both enantiomers during the assay validation. Mean quality control accuracy values were within ±7.3%. Assay recoveries were high (>75%) and consistent across the assay range. The metabolite enantiomers were stable in human blood for 2h on ice. The analytes were also stable in human plasma for 25h at room temperature, 34days at -20°C and -70°C, and following five freeze-thaw cycles. No interconversion of the metabolite enantiomers was detected under any bioanalytical stress conditions, from blood collection/processing through extracted sample storage. The validated assay was successfully applied to the quantification of both metabolite enantiomers in human plasma in support of a human pharmacokinetic study.

Yeast-based assays for screening 11ß-HSD1 inhibitors.

BACKGROUND: Intracellular metabolism of glucocorticoid hormones plays an important role in the pathogenesis of metabolic syndrome and regulates, among many physiological processes, collagen metabolism in skin. At the peripheral level the concentration of active glucocorticoids is mainly regulated by the 11ß-hydroxysteroid dehydrogenase 1 (11ß-HSD1) enzyme, involved in the conversion of cortisone into the biologically active hormone cortisol. Cortisol interacts with the glucocorticoid receptor and regulates the expression of different classes of genes within the nucleus. Due to its implication in glucocorticoid metabolism, the inhibition of 11ß-HSD1 activity has become a dominant strategy for the treatment of metabolic syndrome. Moreover, inhibitors of this target enzyme can be used for development of formulations to counteract skin ageing. Here we present the construction of two yeast cell based assays that can be used for the screening of novel 11ß-HSD1 inhibitors. RESULTS: The yeast Saccharomyces cerevisiae is used as a host organism for the expression of human 11ß-HSD1 as well as a genetically encoded assay system that allows intracellular screening of molecules with 11ß-HSD1 inhibitory activity. As proof of concept the correlation between 11ß-HSD1 inhibition and fluorescent output signals was successfully tested with increasing concentrations of carbenoxolone and tanshinone IIA, two known 11ß-HSD1 inhibitors. The first assay detects a decrease in fluorescence upon 11ß-HSD1 inhibition, whereas the second assay relies on stabilization of yEGFP upon inhibition of 11ß-HSD1, resulting in a positive read-out and thus minimizing the rate of false positives sometimes associated with read-outs based on loss of signals. Specific inhibition of the ABC transporter Pdr5p improves the sensitivity of the assay strains to cortisone concentrations by up to 60 times. CONCLUSIONS: Our yeast assay strains provide a cost-efficient and easy to handle alternative to other currently available assays for the screening of 11ß-HSD1 inhibitors. These assays are designed for an initial fast screening of large numbers of compounds and enable the selection of cell permeable molecules with target inhibitory activity, before proceeding to more advanced selection processes. Moreover, they can be employed in yeast synthetic biology platforms to reconstitute heterologous biosynthetic pathways of drug-relevant scaffolds for simultaneous synthesis and screening of 11ß-HSD1 inhibitors at intracellular level.

In utero perfluorooctane sulfonate exposure causes low body weights of fetal rats: A mechanism study.

OBJECTIVES: The objective of the present study is to investigate the mechanism of perfluorooctane sulfonate-induced low body weight of fetus by analysis of glucocorticoid metabolizing enzyme 11ß-hydroxysteroid dehydrogenase 2 and gene expression profiling of the placenta after in utero PFOS exposure. STUDY DESIGN: Pregnant Sprague-Dawley dams were gavaged with 0, 5, and 20 mg/kg body weight PFOS daily from gestational day 12-18. On gestational day 18, pregnant dams were euthanized, placentas, and fetuses were collected. MAIN OUTCOME MEASURES: Body weights of fetuses and placentas were measured, the corticosterone levels in fetal serum, and 11ß-hydroxysteroid dehydrogenase 2 as well as the placental gene profiling were analyzed. RESULTS: 20 mg/kg PFOS significantly reduced fetal body weight and placental weight. Both 5 and 20 mg/kg PFOS increased fetal serum corticosterone levels. PFOS potently inhibited placental 11ß-hydroxysteroid dehydrogenase 2 activity. Of 21,910 genes, 45 genes were significantly downregulated ≥2 fold by 20 mg/kg PFOS, including extracellular matrix (Slpi and Pi16), growth factors and hormones (Trh and Pdf), ion transporters (Aqp1, S100a4, and Abp1), signal transducers (Kap and Ampd3), and structural constituents (A2m and Des). CONCLUSIONS: PFOS exposure may alter placental development and function, causing intrauterine growth restriction via inhibiting placental 11ß-hydroxysteroid dehydrogenase 2.

Effects of Ziram on Rat and Human 11ß-Hydroxysteroid Dehydrogenase Isoforms.

Ziram is a widely used fungicide for crops. Its endocrine disrupting action is largely unknown. 11ß-Hydroxysteroid dehydrogenases, isoforms 1 (HSD11B1) and 2 (HSD11B2), have been demonstrated to be the regulators of the local levels of active glucocorticoids, which have broad physiological actions. In the present study, the potency of ziram was tested for its inhibition of rat and human HSD11B1 and HSD11B2. Ziram showed the inhibition of rat HSD11B1 reductase with IC50 of 87.07 µM but no inhibition of human enzyme at 100 µM. Ziram showed the inhibition of both rat and human HSD11B2 with IC50 of 90.26 and 34.93 µM, respectively. Ziram exerted competitive inhibition of rat HSD11B1 when 11-dehydrocorticosterone was used and mixed inhibition when NADPH was supplied. Ziram exerted a noncompetitive inhibition of both rat and human HSD11B2 when steroid substrates were used and an uncompetitive inhibition when NAD(+) was supplied. Increased DTT concentrations antagonized rat and human HSD11B2 activities, suggesting that the cysteine residues are associated with the inhibition of ziram. In conclusion, for humans, ziram is a selective inhibitor of HSD11B2, implying that this agent may cause excessive glucocorticoid action in local tissues such as the kidney, brain, and placenta.

An Enantioselective Synthesis of an 11-ß-HSD-1 Inhibitor via an Asymmetric Methallylation Catalyzed by (S)-3,3'-F2-BINOL.

An efficient asymmetric synthesis of 11-ß-HSD inhibitor 1 has been accomplished in five linear steps and 53% overall yield, starting from the readily available 3-chloro-1-phenylpropan-1-one. The key feature of the synthesis includes an asymmetric methallylation of 3-chloro-1-phenylpropan-1-one catalyzed by the highly effective organocatalyst (S)-3,3'-F2-BINOL under solvent-free and metal-free conditions.

Inhibition of 11ß-Hydroxysteroid Dehydrogenase Type II Suppresses Lung Carcinogenesis by Blocking Tumor COX-2 Expression as Well as the ERK and mTOR Signaling Pathways.

Lung cancer is by far the leading cause of cancer death. Early diagnosis and prevention remain the best approach to reduce the overall morbidity and mortality. Experimental and clinical evidence have shown that cyclooxygenase-2 (COX-2) derived prostaglandin E2 (PGE2) contributes to lung tumorigenesis. COX-2 inhibitors suppress the development and progression of lung cancer. However, increased cardiovascular risks of COX-2 inhibitors limit their use in chemoprevention of lung cancers. Glucocorticoids are endogenous and potent COX-2 inhibitors, and their local actions are down-regulated by 11ß-hydroxysteroid dehydrogenase type II (11ßHSD2)-mediated metabolism. We found that 11ßHSD2 expression was increased in human lung cancers and experimental lung tumors. Inhibition of 11ßHSD2 activity enhanced glucocorticoid-mediated COX-2 inhibition in human lung carcinoma cells. Furthermore, 11ßHSD2 inhibition suppressed lung tumor growth and invasion in association with increased tissue active glucocorticoid levels, decreased COX-2 expression, inhibition of ERK and mTOR signaling pathways, increased tumor endoplasmic reticulum stress as well as increased lifespan. Therefore, 11ßHSD2 inhibition represents a novel approach for lung cancer chemoprevention and therapy by increasing tumor glucocorticoid activity, which in turn selectively blocks local COX-2 activity and/or inhibits the ERK and mTOR signaling pathways.

A novel 11ß-hydroxysteroid dehydrogenase type1 inhibitor CNX-010-49 improves hyperglycemia, lipid profile and reduces body weight in diet induced obese C57B6/J mice with a potential to provide cardio protective benefits.

BACKGROUND: 11ß-hydroxysteroid dehydrogenase type1 (11ß-HSD1) converts inactive glucocorticoids to active glucocorticoids which, in excess, leads to development of the various risk factors of the metabolic syndrome. Recent studies clearly suggest that both increased expression and activity of 11ß-HSD1 in metabolically active tissues such as liver, muscle and adipose are implicated in tissue specific dysregulation which collectively contribute to the whole body pathology seen in metabolic syndrome. In the present study we have evaluated CNX-010-49, a highly potent, selective and 'pan tissue' acting 11ß-HSD1 inhibitor, for its potential to modulate multiple risk factors of the metabolic syndrome. METHODS: Male C57B6/J mice on high fat diet (DIO mice) were orally dosed with CNX-010-49 (30 mg/kg twice daily; n = 8) or vehicle for 10 weeks. Fasting glucose, triglycerides, glycerol, free fatty acids, body weight and feed intake were measured at selected time points. At the end of the treatment an OGTT and subsequently organ histology was performed. In vitro, CNX-010-49 was evaluated in 3T3-L1 preadipocytes to assess impact on adipocytes differentiation, hypertrophy and lipolysis whereas in fully differentiated C2C12 cells and in primary mouse hepatocytes to assess the impact on glucose metabolism and hepatic glucose output respectively. RESULTS: CNX-010-49 a highly potent and selective pan tissue acting 11ß-HSD1 inhibitor (EC50 = 6 nM) significantly inhibits glucocorticoids and isoproterenol mediated lipolysis in mature 3T3-L1 adipocytes, improves muscle glucose oxidation, reduces proteolysis and enhances mitochondrial biogenesis. Also a significant inhibition of gluconeogenesis in primary mouse hepatocytes was observed. The treatment with CNX-010-49 resulted in a significant decrease in fasting glucose, improved insulin sensitivity and glucose tolerance. Treatment also resulted in a significant decrease in serum triglycerides levels and a complete inhibition of body weight gain without affecting feed consumption. A significant reduction in the serum biomarkers like Plasminogen activator inhibitor-1 (PAI-1), interleukin 6 (IL-6) and Fetuin-A with CNX-010-49 treatment was observed indicating a potential to modulate processes implicated in cardiovascular benefits. CONCLUSIONS: These results indicate that inhibition of 11ß-HSD1 with CNX-010-49 can give a potential benefit in the management of metabolic dysregulations that are seen in type 2 diabetes.

A mechanism for rapid neurosteroidal regulation of parenting behaviour.

While systemic steroid hormones are known to regulate reproductive behaviour, the actual mechanisms of steroidal regulation remain largely unknown. Steroidogenic enzyme activity can rapidly modulate social behaviour by influencing neurosteroid production. In fish, the enzyme 11ß-hydroxysteroid dehydrogenase (11ß-HSD) synthesizes 11-ketotestosterone (KT, a potent teleost androgen) and deactivates cortisol (the primary teleost glucocorticoid), and both of these steroid hormones can regulate behaviour. Here, we investigated the role of neurosteroidogenesis in regulating parenting in a haremic bidirectionally hermaphroditic fish, Lythrypnus dalli, where males provide all requisite parental care. Using an in vitro assay, we found that an 11ß-HSD inhibitor, carbenoxolone (CBX), reduced brain and testicular KT synthesis by 90% or more. We modulated neurosteroid levels in parenting males via intracerebroventricular injection of CBX. Within only 20 min, CBX transiently eliminated parenting behaviour, but not other social behaviour, suggesting an enzymatic mechanism for rapid neurosteroidal regulation of parenting. Consistent with our proposed mechanism, elevating KT levels rescued parenting when paired with CBX, while cortisol alone did not affect parenting. Females paired with the experimental males opportunistically consumed unattended eggs, which reduced male reproductive success by 15%, but some females also exhibited parenting behaviour and these females had elevated brain KT. Brain KT levels appear to regulate the expression of parenting behaviour as a result of changes in neural 11ß-HSD activity.