11β-HSD1 Expression Research Articles

Local Cortisol Elevation Contributes to Endometrial Insulin Resistance in Polycystic Ovary Syndrome

Endometrial insulin resistance (IR) may account for the endometrial dysfunction in polycystic ovary syndrome (PCOS). The underlying mechanism remains to be elucidated. To investigate whether the abundance of 11β-hydroxysteroid dehydrogenases (11β-HSDs) 1 and 2 and cortisol as well as the insulin signaling pathway are altered in PCOS endometrium and to clarify the relationship between endometrial IR and local cortisol. We measured cortisol and cortisone concentrations, 11β-HSD1 and 11β-HSD2, and core insulin signaling molecules in endometrial biopsies collected from non-PCOS and PCOS with or without IR patients on the seventh day after human chorionic gonadotropin injection. We also studied the effects of cortisol on glucose uptake and the insulin signaling pathway in primary cultured endometrial epithelial cells (EECs). The cortisol concentration was elevated, whereas 11β-HSD2 expression was diminished in endometrial biopsies obtained from PCOS with IR patients compared with those from non-PCOS and PCOS without IR patients. The implantation rate was relatively impaired and the endometrial insulin signaling pathway was defective in PCOS with IR patients. In addition, cortisol attenuated insulin-stimulated glucose uptake in EECs, which was mediated by inhibition of Akt phosphorylation and glucose transporter type 4 translocation via induction of phosphatase and tensin homolog deleted on chromosome ten (PTEN). Decreased oxidation of cortisol and defects of insulin signaling in endometrium were observed in PCOS with IR patients. The excessive cortisol level, derived from the reduction of 11β-HSD2, might contribute to the development of endometrial IR by inhibiting the insulin signaling pathway via induction of PTEN expression in EECs.

11β-HSD Types 1 and 2 in the Songbird Brain.

Glucocorticoid (GC) hormones act on the brain to regulate diverse functions, from behavior and homeostasis to the activity of the hypothalamic–pituitary–adrenal axis. Local regeneration and metabolism of GCs can occur in target tissues through the actions of the 11β-hydroxysteroid dehydrogenases [11 beta-hydroxysteroid dehydrogenase type 1 (11β-HSD1) and 11 beta-hydroxysteroid dehydrogenase type 2 (11β-HSD2), respectively] to regulate access to GC receptors. Songbirds have become especially important model organisms for studies of stress hormone action; however, there has been little focus on neural GC metabolism. Therefore, we tested the hypothesis that 11β-HSD1 and 11β-HSD2 are expressed in GC-sensitive regions of the songbird brain. Localization of 11β-HSD expression in these regions could provide precise temporal and spatial control over GC actions. We quantified GC sensitivity in zebra finch (Taeniopygia guttata) brain by measuring glucocorticoid receptor (GR) and mineralocorticoid receptor (MR) expression across six regions, followed by quantification of 11β-HSD1 and 11β-HSD2 expression. We detected GR, MR, and 11β-HSD2 mRNA expression throughout the adult brain. Whereas 11β-HSD1 expression was undetectable in the adult brain, we detected low levels of expression in the brain of developing finches. Across several adult brain regions, expression of 11β-HSD2 covaried with GR and MR, with the exception of the cerebellum and hippocampus. It is possible that receptors in these latter two regions require direct access to systemic GC levels. Overall, these results suggest that 11β-HSD2 expression protects the adult songbird brain by rapid metabolism of GCs in a context and region-specific manner.

The neuro-endocrine-immune relationship in pulmonary and pleural tuberculosis: a better local profile in pleural fluid.

Tuberculosis (TB) is a major health problem worldwide. In TB, the immune and central nervous systems modulate each other. The two main components of this network are the hypothalamic-pituitary-adrenal axis (HPA) and autonomic nervous system (ANS). To elucidate neuro-endocrine-immune (NEI) interactions in pulmonary (PTB) or pleural (PLTB) TB, we analysed the relationship among compounds from these systems. We quantified levels of catecholamines, hormones and cytokines in plasma from patients with PTB (n = 46) or PLTB (n = 12) and controls (n = 32), and in the pleural fluid from PLTB patients. Transcript expression for genes involved in glucocorticoid-related function (quantitative real-time polymerase chain reaction) was also analysed in mononuclear cells (MCs) from peripheral blood (PBMC) or pleural effusion (PEMC) compartments. Both patient groups had increased plasma levels of pro- and anti-inflammatory cytokines, cortisol, growth hormone (GH) and dopamine, whereas insulin-like growth factor 1 (IGF-1) and dehydroepiandrosterone levels were decreased. The pleural fluid contained increased levels of pro-inflammatory cytokines, GH and IGF-1 and reduced levels of steroid hormones compared with their plasma counterparts. PBMCs from PTB patients had increased expression of transcripts for 11β-hydroxysteroid dehydrogenase (11βHSD1) and a decreased glucocorticoid receptor (GR) ratio (GRα/GRβ). In PLTB cases, expression of 11βHSD1 and GRα transcripts was higher in PEMCs. PTB patients seem to display adverse NEI dysregulation. Changes in pleural fluid are compatible with a more effective NEI reaction.

NAChRs-ERK1/2-Egr-1 signaling participates in the developmental toxicity of nicotine by epigenetically down-regulating placental 11β-HSD2

Impaired placental 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2) activity which inactivates maternal glucocorticoids is associated with poor fetal growth and a higher risk of chronic diseases in adulthood. This study aimed to elucidate the epigenetically regulatory mechanism of nicotine on placental 11β-HSD2 expression. Pregnant Wistar rats were administered 1.0 mg/kg nicotine subcutaneously twice a day from gestational day 9 to 20. The results showed that prenatal nicotine exposure increased corticosterone levels in the placenta and fetal serum, disrupted placental morphology and endocrine function, and reduced fetal bodyweight. Meanwhile, histone modification abnormalities (decreased acetylation and increased di-methylation of histone 3 Lysine 9) on the HSD11B2 promoter and lower-expression of 11β-HSD2 were observed. Furthermore, the expression of nicotinic acetylcholine receptor (nAChR) α4/β2, the phosphorylation of extracellular regulated kinase 1/2 (ERK1/2) and Ets-like protein-1 (Elk-1), and the expression of early growth response-1 (Egr-1) were increased in the nicotine groups. In human BeWo cells, nicotine decreased 11β-HSD2 expression, increased nAChRα9 expression, and activated ERK1/2/Elk-1/Egr-1 signaling in the concentration (0.1–10 μM)-dependent manner. Antagonism of nAChRs, inhibition of ERK1/2 and Egr-1 knockdown by siRNA were able to block/abrogate the effects of nicotine on histone modification and expression of 11β-HSD2. Taken together, nicotine can impair placental structure and function, and induce fetal developmental toxicity. The underlying mechanism involves histone modifications and down-regulation of 11β-HSD2 through nAChRs/ERK1/2/Elk-1/Egr-1 signaling, which increases active glucocorticoids levels in the placenta and fetus, and eventually inhibits the fetal development.

Role of 11β-HSD type 1 in abnormal HPA axis activity during immune-mediated arthritis.

Patients with chronic immune-mediated arthritis exhibit abnormal hypothalamo-pituitary-adrenal (HPA) axis activity. The basis for this abnormality is not known. Immune-mediated arthritis is associated with increased extra-adrenal synthesis of active glucocorticoids by the 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) enzyme. 11β-HSD1 is expressed in the central nervous system, including regions involved in HPA axis regulation. We examined whether altered 11β-HSD1 expression within these regions contributes to HPA axis dysregulation during arthritis. The expression of 11β-HSD1, and other components of glucocorticoid signaling, were examined in various brain regions and the pituitary gland of mice with experimentally induced arthritis. Two arthritis protocols were employed: The K/BxN spontaneous arthritis model for chronic arthritis and the K/BxN serum transfer arthritis model for acute arthritis. 11β-HSD1 mRNA (Hsd11b1) was expressed in the hippocampus, hypothalamus, cortex, cerebellum and pituitary gland. Hypothalamic Hsd11b1 expression did not change in response to arthritis in either model. Pituitary Hsd11b1 expression was however significantly increased in both chronic and acute arthritis models. Hippocampal Hsd11b1 was decreased in acute but not chronic arthritis. Chronic, but not acute, arthritis was associated with a reduction in hypothalamic corticotropin-releasing hormone and arginine vasopressin expression. In both models, serum adrenocorticotropic hormone and corticosterone levels were no different from non-inflammatory controls. These findings demonstrate inflammation-dependent regulation of Hsd11b1 expression in the pituitary gland and hippocampus. The upregulation of 11β-HSD1 expression in the pituitary during both chronic and acute arthritis, and thus, an increase in glucocorticoid negative feedback, could contribute to the abnormalities in HPA axis activity seen in immune-mediated arthritis.

Inhibition of Osteoblast Function by Brucella abortus is Reversed by Dehydroepiandrosterone and Involves ERK1/2 and Estrogen Receptor.

Brucella abortus induces an inflammatory response that stimulates the endocrine system resulting in the secretion of cortisol and dehydroepiandrosterone (DHEA). Osteoarticular brucellosis is the most common presentation of the active disease in humans, and we have previously demonstrated that B. abortus infection inhibits osteoblast function. We aimed to evaluate the role of cortisol and DHEA on osteoblast during B. abortus infection. B. abortus infection induces apoptosis and inhibits osteoblast function. DHEA treatment reversed the effect of B. abortus infection on osteoblast by increasing their proliferation, inhibiting osteoblast apoptosis, and reversing the inhibitory effect of B. abortus on osteoblast differentiation and function. By contrast, cortisol increased the effect of B. abortus infection. Cortisol regulates target genes by binding to the glucocorticoid receptor (GR). B. abortus infection inhibited GRα expression. Cell responses to cortisol not only depend on GR expression but also on its intracellular bioavailability, that is, dependent on the activity of the isoenzymes 11β-hydroxysteroid dehydrogenase (HSD) type-1, 11β-HSD2 (which convert cortisone to cortisol and vice versa, respectively). Alterations in the expression of these isoenzymes in bone cells are associated with bone loss. B. abortus infection increased 11β-HSD1 expression but had no effect on 11β-HSD2. DHEA reversed the inhibitory effect induced by B. abortus infection on osteoblast matrix deposition in an estrogen receptor- and ERK1/2-dependent manner. We conclude that DHEA intervention improves osteoblast function during B. abortus infection making it a potential candidate to ameliorate the osteoarticular symptoms of brucellosis.

Overexpression of 11β-hydroxysteroid dehydrogenase 1 in visceral adipose tissue and underexpression of endothelial nitric oxide synthase in the adrenal cortex of dogs with hyperadrenocorticism.

11β-Hydroxysteroid dehydrogenase 1 (11β-HSD1) is an enzyme that activates cortisone into cortisol in tissues. Alterations in this enzyme are related to the development of metabolic syndrome, obesity and hyperadrenocorticism (HAC). Endothelial nitric oxide synthase (eNOS) produces nitric oxide and is related to the regulation of adrenal steroidogenesis. The aim of the study was to evaluate 11β-HSD1 and eNOS expression in dogs with HAC. Visceral adipose tissue samples were taken to evaluate 11β-HSD1 expression by immunohistochemistry and western blotting. In parallel, adrenal gland samples were collected to evaluate eNOS expression by immunohistochemistry. 11β-HSD1 expression was significantly higher in the adipocytes of dogs with HAC than in those of the control dogs. eNOS expression in the adrenal cortex (zona fasciculata) was significantly lower in the dogs with HAC than in the control dogs. 11β-HSD1 overexpression and eNOS underexpression could play a role in the maintenance of hypercortisolism in dogs with HAC.

Psychosocial stress sensitizes neuroendocrine and inflammatory responses to Escherichia coli challenge in domestic piglets

Exposure to psychosocial stress can have a profound impact on immune reactivity and health mediated by hypothalamic–pituitaryadrenal (HPA) axis activation. However, current knowledge regarding the mechanisms involved in cross-sensitization between stress and the immune system is limited. Here, we investigated the effects of a single social isolation followed by repeated oral Escherichia coli (E. coli) applications on cortisol, tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), haptoglobin and C-reactive protein (CRP) concentrations in the blood; on clinical signs of disease; and on mRNA expression of the glucocorticoid receptor (GR), mineralocorticoid receptor (MR), 11β-hydroxysteroid dehydrogenase 1 and 2 (11β-HSD1 and 11β-HSD2), TNF-α and IL-6 in the hypothalamus, prefrontal cortex (PFC) and spleen of 7-, 21- and 35-day-old piglets. Additionally, the protein levels of splenic TNF-α and IL-6 were analyzed. Non-isolated, E. coli-challenged piglets served as a control. Social isolation for 4 h induced a rise in the plasma cortisol concentrations immediately after social treatment and after repeated E. coli applications in isolated compared to non-isolated piglets. The circulating TNF-α concentration was not affected by social treatment. Furthermore, previously isolated piglets showed a higher frequency of signs of disease in response to E. coli challenge than non-isolated piglets, while the haptoglobin and CRP concentrations did not significantly differ between social treatments. In the brain, 11β-HSD1, 11β-HSD2 and IL-6 mRNA expression in the hypothalamus and GR, and 11β-HSD1 and 11β-HSD2 mRNA expression in the PFC were higher in isolated, E. coli-challenged piglets than in the corresponding controls. Moreover, isolated piglets also displayed higher MR, 11β-HSD1 and IL-6 mRNA expression levels and TNF-α concentrations in the spleen. The stress-induced alterations in the hypothalamus and spleen were particularly pronounced in younger piglets. The present findings may contribute to a better understanding of the complex interplay between early psychological stress and an increased risk of disease and might also have implications on aspects of the health and welfare of farm animals and humans.

Citrinal B, natural 11 beta-hydroxysteroid dehydrogennase type 1 inhibitor identified from structure-based virtual screening

Citrinal B, a tricyclic compound from endophytic fungus Colletotrichum capsici in our previous studies, exhibited significant inhibitory activity against 11β-hydroxysteroid dehydrogenase type 1 (11 β-HSD1) in vitro and showed strong binding affinity to 11β-HSD1. Moreover, citrinal B treatments decreased the lipid droplet accumulation associate with the inhibition of 11β-HSD1 expression in differentiate induced 3T3-L1 preadipocytes. Furthermore, the molecular docking demonstrated that citrinal B coordinated in the active site of 11β-HSD1 is essential for the ability of diminishing the enzyme activity.

The Role and Regulation of the 11 Beta-Hydroxysteroid Dehydrogenase Enzyme System in Patients with Inflammatory Bowel Disease.

Glucocorticoids are known to modulate a number of immunological responses including counteracting inflammation. Within tissues expressing the glucocorticoid and mineralocorticoid receptors including the colon, glucocorticoid metabolism is regulated by the isoenzymes of 11ß-hydroxysteroid dehydrogenase (11β-HSD). 11β-HSD1 acts as an oxidoreductase converting inactive cortisone into active cortisol, while 11β-HSD2 acts as a dehydrogenase converting active cortisol to inactive cortisone. Hexose-6 phosphate dehydrogenase (H6PDH) is a key regulator of 11β-HSD1 activity via its generation of NADPH. Variations in the 11β-HSD enzyme system in relation to levels of expression and regulation may have a role in IBD. The aim of this study was to investigate possible abnormalities of 11β-HSD enzyme system in the colon of patients with IBD. By using quantitative real-time PCR, we investigated the transcription levels of 11β-HSD1 and 2 in colonic tissue from IBD patients and healthy controls undergoing a colonoscopy for disease assessment. Disease activity was recorded using clinical (Mayo Score/Harvey-Bradshaw Index), Biochemical (C-reactive protein), histological, and endoscopic parameters. In addition, transcription levels of H6PDH and the glucocorticoid receptor alpha (GR-α) as well as key pro-inflammatory cytokines (TNF-α, IL-1β, IL-6, Rela (subunit for NF Kappa B)) were later examined among this group, and results were correlated with 11β-HSD2 gene expression. Results and patient demographics were expressed as a mean (and SD), and differences between IBD patients and control groups were analyzed using a Student's t test or Mann-Whitney U test as appropriate, with a p value of ≤0.05 considered significant. Results were controlled for disease activity as outlined above. Results have demonstrated a significant downregulation in 11β-HSD2 expression in IBD patients compared with controls (13.8±17.1 au vs. 318.4±521.1au, p=0.01), whereas levels of 11β-HSD1 did not appear to vary across the two groups. Among IBD patients, there was a trend toward higher 11β-HSD1 expression in inflamed tissue compared with matched non-inflamed tissue (422.1±944 au vs. 102.2±103.9, P=0.09). Levels of H6PDH and the GR-α expression did not appear to vary among active inflamed IBD tissue and controls. As a result, we examined the association between pro-inflammatory cytokines and levels of 11β-HSD2 expression. Results showed an upregulation of key pro-inflammatory cytokine mRNA expression (TNF-α, IL-1β, IL-6) during inflammation with an associated downregulation of 11β-HSD2 mRNA expression when compared to controls. Dysregulation in this pathway could have a potential role in IBD pathogenesis and may account for exogenous glucocorticoid resistance in IBD. Further work assessing the role of the 11β-HSD enzyme system in steroid-resistant subjects is warranted.

11β-HSD2 SUMOylation Modulates Cortisol-Induced Mineralocorticoid Receptor Nuclear Translocation Independently of Effects on Transactivation.

The enzyme 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2) has an essential role in aldosterone target tissues, conferring aldosterone selectivity for the mineralocorticoid receptor (MR) by converting 11β-hydroxyglucocorticoids to inactive 11-ketosteroids. Congenital deficiency of 11β-HSD2 causes a form of salt-sensitive hypertension known as the syndrome of apparent mineralocorticoid excess. The disease phenotype, which ranges from mild to severe, correlates well with reduction in enzyme activity. Furthermore, polymorphisms in the 11β-HSD2 coding gene (HSD11B2) have been linked to high blood pressure and salt sensitivity, major cardiovascular risk factors. 11β-HSD2 expression is controlled by different factors such as cytokines, sex steroids, or vasopressin, but posttranslational modulation of its activity has not been explored. Analysis of 11β-HSD2 sequence revealed a consensus site for conjugation of small ubiquitin-related modifier (SUMO) peptide, a major posttranslational regulatory event in several cellular processes. Our results demonstrate that 11β-HSD2 is SUMOylated at lysine 266. Non-SUMOylatable mutant K266R showed slightly higher substrate affinity and decreased Vmax, but no effects on protein stability or subcellular localization. Despite mild changes in enzyme activity, mutant K266R was unable to prevent cortisol-dependent MR nuclear translocation. The same effect was achieved by coexpression of wild-type 11β-HSD2 with sentrin-specific protease 1, a protease that catalyzes SUMO deconjugation. In the presence of 11β-HSD2-K266R, increased nuclear MR localization did not correlate with increased response to cortisol or increased recruitment of transcriptional coregulators. Taken together, our data suggests that SUMOylation of 11β-HSD2 at residue K266 modulates cortisol-mediated MR nuclear translocation independently of effects on transactivation.

Protective effects of carbenoxolone, an 11β-HSD1 inhibitor, against chemical induced dry eye syndrome.

Dry eye syndrome (DES) is a disorder of the eye due to tear deficiency or excessive evaporation that causes damage to the eye and is associated with discomfort and dryness. 11β-Hydroxysteroid dehydrogenase 1 (11β-HSD1) is an enzyme that converts inactive cortisone to active cortisol. Recently, 11β-HSD1 has been expressed in human and rodent eyes and has been recognized as a target of glaucoma. In this study, the therapeutic effects and underlying mechanisms of topical carbenoxolone, an 11β-HSD1 inhibitor, were investigated in benzalkonium chloride (BAC)-treated human conjunctival epithelial cells and a rat DES model. In the in vitro study, carbenoxolone dose-dependently inhibited cell death and 11β-HSD1 activity in BAC-treated human conjunctival epithelial cells. For the in vivo study, carbenoxolone or a solvent was administered to the BAC-induced DES model twice daily. BAC-treated rat eyes showed significant increases in ocular surface damage, a reduction of tears, decrease corneal thickness, corneal basement membrane destruction, apoptosis in the conjunctival epithelium, and expression of pro-inflammatory cytokines (TNF-α and IL-6) and 11β-HSD1. These effects of BAC were reversed by topical carbenoxolone treatment. These results demonstrate that carbenoxolone can prevent DES by inhibiting pro-inflammatory cytokine expression and cell death of the corneal and conjunctival epithelium via inhibition of both 11β-HSD1 activity and expression in the eyes of BAC-treated rats. It is suggested that topical 11β-HSD1 inhibitors may provide a new therapeutic window in the prevention and/or treatment of DES.

Characterisation of the cancer-associated glucocorticoid system: key role of 11\u03b2-hydroxysteroid dehydrogenase type 2

Background:Recent studies have shown that production of cortisol not only takes place in several non-adrenal peripheral tissues such as epithelial cells but, also, the local inter-conversion between cortisone and cortisol is regulated by the 11β-hydroxysteroid dehydrogenases (11β-HSDs). However, little is known about the activity of this non-adrenal glucocorticoid system in cancers.Methods:The presence of a functioning glucocorticoid system was assessed in human skin squamous cell carcinoma (SCC) and melanoma and further, in 16 epithelial cell lines from 8 different tissue types using ELISA, western blotting and immunofluorescence. 11β-HSD2 was inhibited both pharmacologically and by siRNA technology. Naïve CD8+ T cells were used to test the paracrine effects of cancer-derived cortisol on the immune system in vitro. Functional assays included cell–cell adhesion and cohesion in two- and three-dimensional models. Immunohistochemical data of 11β-HSD expression were generated using tissue microarrays of 40 cases of human SCCs as well as a database featuring 315 cancer cases from 15 different tissues.Results:We show that cortisol production is a common feature of malignant cells and has paracrine functions. Cortisol production correlated with the magnitude of glucocorticoid receptor (GR)-dependent inhibition of tumour-specific CD8+ T cells in vitro. 11β-HSDs were detectable in human skin SCCs and melanoma. Analyses of publicly available protein expression data of 11β-HSDs demonstrated that 11β-HSD1 and -HSD2 were dysregulated in the majority (73%) of malignancies. Pharmacological manipulation of 11β-HSD2 activity by 18β-glycyrrhetinic acid (GA) and silencing by specific siRNAs modulated the bioavailability of cortisol. Cortisol also acted in an autocrine manner and promoted cell invasion in vitro and cell–cell adhesion and cohesion in two- and three-dimensional models. Immunohistochemical analyses using tissue microarrays showed that expression of 11β-HSD2 was significantly reduced in human SCCs of the skin.Conclusions:The results demonstrate evidence of a cancer-associated glucocorticoid system and show for the first time, the functional significance of cancer-derived cortisol in tumour progression.

Role of FKBP51 in the modulation of the expression of the corticosteroid receptors in bovine thymus following glucocorticoid administration

The aim of this work was to study the transcriptional effects of glucocorticoids on corticosteroid hormone receptors, prereceptors (11β-hydroxysteroid dehydrogenase 1 and 2, 11β-HSD1 and 2), and chaperones molecules regulating intracellular trafficking of the receptors (FKBP51 and FKBP52) in thymus of veal calves. Moreover, the expression of FKBP51 and FKBP52 gene were investigated in beef cattle thymus. In the cervical thymus of veal calves, dexamethasone administration in combination with estradiol decreased FKBP51 expression (P < 0.01). The same treatment increased mineralocorticoid receptor (MR) (P < 0.01) and 11β-HSD1 expression (P < 0.05) compared to control group in the cervical thymus of veal calves. The thoracic thymus of veal calves treated with dexamethasone and estradiol showed a decrease of FKBP51 (P < 0.05), FKBP52 (P < 0.05), glucocorticoid receptor (P < 0.05), and MR expression (P < 0.05) compared to control group in the thoracic thymus of veal calves. The gene expression of FKBP51 decreased both in cervical (P < 0.01) and thoracic thymus (P < 0.01) of beef cattle treated with dexamethasone and estradiol. In addition, also prednisolone administration reduced FKBP51 expression in the cervical thymus (P < 0.01) and in the thoracic thymus of beef cattle (P < 0.01). The gene expression of FKBP52 increased only in the cervical thymus following dexamethasone administration (P < 0.01). The decrease of FKBP51 gene expression in thymus could be a possible biomarker of illicit dexamethasone administration in bovine husbandry. Moreover, so far, an effective biomarker of prednisolone administration is not identified. In this context, the decrease of FKBP51 gene expression in thymus of beef cattle following prednisolone administration could play an important role in the indirect identification of animals illegally treated with prednisolone.

Maternal obesity programs reduced leptin signaling in the pituitary and altered GH/IGF1 axis function leading to increased adiposity in adult sheep offspring.

Studies in rodents highlight a role for leptin in stimulation of pituitary growth hormone (GH) secretion, with an impact on body composition regulation. We have reported that maternal obesity (MO) during ovine pregnancy results in hyperphagia, glucose-insulin dysregulation, increased adiposity, hypercortisolemia and hyperleptinemia in mature offspring subjected to a bout of ad libitum feeding. We hypothesized that MO reduces leptin signaling in the pituitary and down regulates the GH/IGF1 axis and increases circulating cortisol leading to increased adiposity in their adult offspring. Male lambs born to MO (n = 6) or control (CON, n = 6) ewes were fed only to requirements until placed on a 12 week ad libitum feeding trial at maturity. The pituitary, hypothalamic arcuate nucleus, and liver were collected at necropsy and mRNA and protein expression determined. Plasma cortisol concentrations were increased (P<0.05) in MO vs. CON offspring at the end of the feeding trial. Further, serum concentrations of IGF1 decreased (P<0.01) and GH tended to decrease (P<0.08) in MO vs. CON offspring. Pituitary mRNA and leptin receptor protein expression were decreased in MO vs. CON offspring in association with decreased GH mRNA expression, and decreased IGF1 mRNA and protein expression in liver. Liver 11β-hydroxysteroid dehydrogenase 1 (11βHSD1) expression was increased (P<0.01) and its cofactor hexose-6-phosphate dehydrogenase tended to increase (P<0.06) in MO vs. CON offspring. 11βHSD2 expression remained unchanged. These data indicate that MO induced an increase in liver conversion of cortisone to cortisol in adult offspring and support a role for leptin signaling in the pituitary in mediating offspring adiposity.

Interplay between H6PDH and 11β-HSD1 implicated in the pathogenesis of type 2 diabetes mellitus

Extensive studies have been performed on the role of 11β-hydroxysteroid dehydrogenase 1 (11β-HSD1) in metabolic diseases. Our previous study reported glucose could directly regulate hexose-6-phosphate dehydrogenase (H6PDH) and 11β-HSD1. Recently, we further investigated the interplay of H6PDH and 11β-HSD1 and their roles in hepatic gluconeogenesis and insulin resistance to elucidate the importance of H6PDH and 11β-HSD1 in pathogenesis of type 2 diabetes mellitus (T2DM). T2DM rats model and H6PDH or 11β-HSD1 siRNA transfected in CBRH-7919 cells were used to explore the effect of H6PDH and 11β-HSD1 in T2DM. The results showed that the expression and activity of H6PDH and 11β-HSD1 in livers of diabetic rats were increased, with the expressions of PEPCK and G6Pase or liver corticosterone increased apparently. It also showed that H6PDH siRNA and 11β-HSD1 siRNA could inhibit the protein expression and enzyme activity by each other. With H6PDH siRNA, the enhancement of gluconeogenesis was blocked and insulin resistance stimulated by corticosterone was reduced. H6PDH and 11β-HSD1 might be the effective and prospective targets for T2DM and metabolic syndromes, based on the interplay between these two enzymes.

Carbenoxolone prevents chemical eye ischemia-reperfusion-induced cell death via 11β-hydroxysteroid dehydrogenase type 1 inhibition

Glaucoma is one of the leading causes of preventable blindness diseases, affecting more than 2 million people in the United States. Recently, 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) inhibitors were found to exert preventive effects against glaucoma. Therefore, we investigated whether carbenoxolone (CBX), an 11β-HSD1 inhibitor, prevents chemical ischemia-reperfusion-induced cell death in human trabecular meshwork (HTM) cells. The present study demonstrated that CBX inhibited cell death caused by iodoacetic acid (IAA)-induced ischemia-reperfusion, and its effect was associated with the inhibition of 11β-HSD1 expression and activity. Furthermore, CBX reversed the IAA-induced structural damage on filamentous actin in HTM cells. In IAA-treated cells, the levels of 11β-HSD1 and the apoptosis-related factors Bax and FASL were increased throughout the reperfusion period, and CBX was able to attenuate the expression of 11β-HSD1 and the apoptosis-related factors. CBX also effectively suppressed IAA-induced intracellular ROS formation and cytochrome c release, which are involved in the mitochondrial apoptosis pathway. In addition, IAA-induced chemical ischemia-reperfusion stimulated TNF-α expression and NF-κB p65 phosphorylation, and these effects were attenuated by CBX. 11β-HSD1 RNAi also suppressed IAA-induced cell apoptosis via reduction of oxidative stress and inhibition of the pro-inflammatory pathway. Taken together, the present study demonstrated that the inhibition of 11β-HSD1 protected the TM against chemical ischemia-reperfusion injury, suggesting that the use of 11β-HSD1 inhibitors could be a useful strategy for glaucoma therapy.

Abstract 5213: Aberrant tumor metabolism enables GR takeover in enzalutamide-resistant prostate cancer

Abstract It is well known that castration resistant prostate cancer (CRPC) is still driven by the androgen axis. Therefore, the advent of new AR-targeting drugs, such as Enzalutamide (ENZ), has been beneficial for many patients with CRPC. ENZ is a potent FDA-approved AR antagonist which prolongs survival for patients with CRPC, even after docetaxel chemotherapy. Unfortunately, although ENZ has proven effective clinically, treatment resistance eventually arises in nearly all patients with CRPC. Emerging data suggest that the glucocorticoid receptor (GR) is upregulated in this context, stimulating expression of AR-target genes that permit continued growth despite AR blockade. Hence, we hypothesize that similar to metabolic mechanisms that elicit dihydrotestosterone (DHT) synthesis, which in turn stimulate AR in CRPC, a role for GR in ENZ resistance would be accompanied by a tumor metabolic switch that provides sustained tissue cortisol concentrations which enable GR activation. Here, we found that long-term ENZ treatment sustains tumor cortisol concentrations in models of prostate cancer and patient tissues by using [3H]-cortisol and high performance liquid chromatography. Further investigations with immunoblot, co-immunoprecipitation as well as in vitro ubiquitination assays in ENZ resistant prostate cancer models demonstrated that autocrine motility factor receptor (AMFR), an ubiquitin E3-ligase, and one of its adaptors, Erlin-2, mediate loss of 11β-hydroxysteroid dehydrogenase-2 (11β-HSD2), which sustains tumor cortisol concentrations, resulting in the continuous stimulation of GR and ENZ resistance. Remarkably, reinstatement of 11β-HSD2 expression, or AMFR loss, reverses ENZ resistance in mouse xenograft tumors. Together, these findings reveal a surprising metabolic mechanism of ENZ resistance that may be targeted with a strategy that circumvents a requirement for systemic GR ablation. Citation Format: Jianneng Li. Aberrant tumor metabolism enables GR takeover in enzalutamide-resistant prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5213. doi:10.1158/1538-7445.AM2017-5213

In obese mice, exercise training increases 11β-HSD1 expression, contributing to glucocorticoid activation and suppression of pulmonary inflammation.

Exercise training is advocated for treating chronic inflammation and obesity-related metabolic syndromes. Glucocorticoids (GCs), the anti-inflammatory hormones, are synthesized or metabolized in extra-adrenal organs. This study aims to examine whether exercise training affects obesity-associated pulmonary inflammation by regulating local GC synthesis or metabolism. We found that sedentary obese (ob/ob) mice exhibited increased levels of interleukin (IL)-1β, IL-18, monocyte chemotactic protein (MCP)-1, and leukocyte infiltration in lung tissues compared with lean mice, which was alleviated by 6 wk of exercise training. Pulmonary corticosterone levels were decreased in ob/ob mice. Exercise training increased pulmonary corticosterone levels in both lean and ob/ob mice. Pulmonary corticosterone levels were negatively correlated with IL-1β, IL-18, and MCP-1. Immunohistochemical staining of the adult mouse lung sections revealed positive immunoreactivities for the steroidogenic acute regulatory protein, the cholesterol side-chain cleavage enzyme (CYP11A1), the steroid 21-hydroxylase (CYP21), 3β-hydroxysteroid dehydrogenase (3β-HSD), and type 1 and type 2 11β-hydroxysteroid dehydrogenase (11β-HSD) but not for 11β-hydroxylase (CYP11B1). Exercise training significantly increased pulmonary 11β-HSD1 expression in both lean and ob/ob mice. In contrast, exercise training per se had no effect on pulmonary 11β-HSD2 expression, although pulmonary 11β-HSD2 levels in ob/ob mice were significantly higher than in lean mice. RU486, a glucocorticoid receptor antagonist, blocked the anti-inflammatory effects of exercise training in lung tissues of obese mice and increased inflammatory cytokines in lean exercised mice. These findings indicate that exercise training increases pulmonary expression of 11β-HSD1, thus contributing to local GC activation and suppression of pulmonary inflammation in obese mice.NEW & NOTEWORTHY Treadmill training leads to a significant increase in pulmonary corticosterone levels in ob/ob mice, which is in parallel with the favorable effects of exercise on obesity-associated pulmonary inflammation. Exercise training increases pulmonary 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) expression but has no significant effect on 11β-HSD2 expression in both lean and ob/ob mice. These findings indicate that exercise training increases pulmonary expression of 11β-HSD1, thus contributing to local glucocorticoid activation and suppression of pulmonary inflammation in obese mice.

Fructose, Glucocorticoids and Adipose Tissue: Implications for the Metabolic Syndrome.

The modern Western society lifestyle is characterized by a hyperenergetic, high sugar containing food intake. Sugar intake increased dramatically during the last few decades, due to the excessive consumption of high-sugar drinks and high-fructose corn syrup. Current evidence suggests that high fructose intake when combined with overeating and adiposity promotes adverse metabolic health effects including dyslipidemia, insulin resistance, type II diabetes, and inflammation. Similarly, elevated glucocorticoid levels, especially the enhanced generation of active glucocorticoids in the adipose tissue due to increased 11β-hydroxysteroid dehydrogenase 1 (11β-HSD1) activity, have been associated with metabolic diseases. Moreover, recent evidence suggests that fructose stimulates the 11β-HSD1-mediated glucocorticoid activation by enhancing the availability of its cofactor NADPH. In adipocytes, fructose was found to stimulate 11β-HSD1 expression and activity, thereby promoting the adipogenic effects of glucocorticoids. This article aims to highlight the interconnections between overwhelmed fructose metabolism, intracellular glucocorticoid activation in adipose tissue, and their metabolic effects on the progression of the metabolic syndrome.