11β-HSD1 Activity Research Articles

A possible direct action of oxytocin on spermatogenesis and steroidogenesis in pre-pubertal mouse.

The aim of this study was to evaluate the effects of in vivo and in vitro treatments of oxytocin (OT) on the testis of pre-pubertal mice. The OT treatment produced significant changes in the spermatogenic and steroidogenic activity by increasing expression of OT-receptor in the testis of pre-pubertal mice. Treatment with OT showed increased proliferation of germ cells as indicated by increased number of spermatocytes and round spermatids. Dose-dependent increase in expression of PCNA, Bcl-2 and AR proteins was observed in the testis of OT-treated mice as compared with the control and further supports the role of OT in germ cell proliferation and survival. The pre-pubertal mice treated with increasing dose of OT showed significant increase in testosterone synthesis due to dose-dependent stimulatory effects on 3β-HSD activity and increased expression of STAR, LH-receptor (LH-R) and gonadotrophin-releasing hormone receptor (GnRH-R) proteins in the testis. The in vitro study has confirmed in vivo finding showing direct action of OT on testicular steroidogenesis. Thus, OT stimulates testicular spermatogenesis and steroidogenesis by directly acting on testis in mice.

Curcumin and Quercetin Ameliorated Cypermethrin and Deltamethrin-Induced Reproductive System Impairment in Male Wistar Rats by Upregulating The Activity of Pituitary-Gonadal Hormones and Steroidogenic Enzymes.

BackgroundDietary antioxidants protect tissues and organs against insecticides/xenobiotic-induced damage. In the present study, we evaluated the results of exposure to synthetic pyrethroid insecticides, cypermethrin (Cyp) and deltamethrin (Del) and possible protective effects of curcumin and quercetin on reproductive system in male Wistar rats.Materials and MethodsIn this controlled experimental study, 42 male Wistar rats were randomly divided into 7 groups of 6 animals. Group A served as control, group B was exposed to Cyp (2 mg/kg.bw), group C was exposed to Del (2 mg/kg.bw), group D was exposed to Cyp+Del (2 mg/kg.bw each), group E was exposed to Cyp+Del and treated with curcumin (100 mg/kg.bw), group F was exposed to Cyp+Del and treated with quercetin (100 mg/kg.bw) and group G was exposed to Cyp+Del and treated with quercetin+curcumin for 45 days.ResultsExposure to Cyp and Del caused decreases in reproductive organs weight, sperm count, sperm motility, level of sex hormones viz. testosterone (T), follicle stimulating hormone (FSH) and luteinizing hormone (LH), steroidogenic enzymes viz. 3β-hydroxyl steroid dehydrogenase (3β-HSD) and 17β-HSD, non-enzymatic antioxi- dant glutathione (GSH) and enzymatic antioxidants viz. superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione-S-transferase (GST) and glutathione reductase (GR) activity and increases in sperm abnormalities and lipid peroxidation (LPO). The exposure also adversely affected the histo-achitecture of testes. Single and combined treatment with curcumin and quercetin significantly ameliorated Cyp and Del-induced damage in reproductive system.ConclusionCurcumin and quercetin protected against Cyp and Del-induced reproductive system toxicity and oxidative damage in rats. The increases in activities of 3β-HSD and 17β-HSD with concomitant increases in testosterone were mainly responsible for ameliorating effects of curcumin and quercetin. Curcumin showed slightly better activity as compared to quercetin. The combination of both antioxidants offered more protection compared to each one alone.

Tribulus terrestris Protects against Male Reproductive Damage Induced by Cyclophosphamide in Mice.

Tribulus terrestris (TT) has been considered as a potential stimulator of testosterone production, which has been related with steroidal saponins prevailing in this plant. Cyclophosphamide (CP) is the most commonly used anticancer and immunosuppressant drug, which causes several toxic effects, especially on the reproductive system. Patients who need to use CP therapy exhibit reduced fertility or infertility, which impacts both physically and emotionally on the decision to use this drug, especially among young men. We hypothesized that the treatment with TT dry extract would protect the male reproductive system against CP toxicity. Mice received dry extract of TT (11 mg/kg) or vehicle by gavage for 14 days. Saline or CP was injected intraperitoneally at a single dose (100 mg/kg) on the 14th day. Animals were euthanized 24 h after CP administration, and testes and epididymis were removed for biochemical and histopathological analysis and sperm evaluation. The dry extract of TT was evaluated by HPLC analysis and demonstrated the presence of protodioscin (1.48%, w/w). CP exposure increased lipid peroxidation, reactive species, and protein carbonylation and altered antioxidant enzymes (SOD, CAT, GPx, GST, and GR). Moreover, acute exposure to CP caused a reduction on 17 β-HSD activity, which may be related to the reduction in serum testosterone levels, histopathological changes observed in the testes, and the quality of the semen. The present study highlighted the role of TT dry extract to ameliorate the alterations induced by CP administration in mice testes, probably due to the presence of protodioscin.

Copeptin and insulin resistance: effect modification by age and 11 β-HSD2 activity in a population-based study.

Arginine vasopressin (AVP) may be involved in metabolic syndrome (MetS) by altering liver glycogenolysis, insulin and glucagon secretion, and pituitary ACTH release. Moreover, AVP stimulates the expression of 11β-hydroxysteroid-dehydrogenase-type 2 (11β-HSD2) in mineralocorticosteroid cells. We explored whether apparent 11β-HSD2 activity, estimated using urinary cortisol-to-cortisone ratio, modulates the association between plasma copeptin, as AVP surrogate, and insulin resistance/MetS in the general adult population. This was a multicentric, family-based, cross-sectional sample of 1089 subjects, aged 18-90years, 47% men, 13.4% MetS, in Switzerland. Mixed multivariable linear and logistic regression models were built to investigate the association of insulin resistance (HOMA-IR)/fasting glucose and MetS/Type 2 Diabetes with copeptin, while considering potential confounders or effect modifiers into account. Stratified results by age and 11β-HSD2 activity were presented as appropriate. Plasma copeptin was higher in men [median 5.2, IQR (3.7-7.8)pmol/L] than in women [median 3.0, IQR (2.2-4.3)pmol/L], P<0.0001. HOMA-IR was positively associated with copeptin after full adjustment if 11β-HSD2 activity was high [β (95% CI)=0.32 (0.17-0.46), P<0.001] or if age was high [β (95% CI)=0.34 (0.20-0.48), P<0.001], but not if either 11β-HSD2 activity or age was low. There was a positive association of type 2 diabetes with copeptin [OR (95% CI)=2.07 (1.10-3.89), P=0.024), but not for MetS (OR (95% CI)=1.12 (0.74-1.69), P=0.605), after full adjustment. Our data suggest that age and apparent 11β-HSD2 activity modulate the association of copeptin with insulin resistance at the population level but not MeTS or diabetes. Further research is needed to corroborate these results and to understand the mechanisms underlying these findings.

Apparent systemic 11ß-dehydroxysteroid dehydrogenase 2 activity is increased in preeclampsia but not in intrauterine growth restriction.

The enzyme 11ß-dehydroxysteroid dehydrogenase 2 (11ß-HSD2) converts active cortisol (F) to inactive cortisone (E). A reduced 11ß-HSD2 activity in the placenta has been demonstrated for prematurity, low birth weight, and preeclampsia. We hypothesized that disturbed placental function rather than a maternal response contributes to decreased 11ßHSD2 activity as reflected by a diminished conversion of F to E. Hence, the aim of the present study was to estimate the systemic activity of 11ß-HSD2 throughout gestation and in pregnancies complicated by preeclampsia (PE) and intrauterine growth restriction (IUGR) by calculating maternal serum F/E ratios. A total of 188 maternal serum samples were analyzed for nine glucocorticoid metabolites by gas chromatography-mass spectrometry (GC-MS) and F/E ratios were calculated. Study Group A: In a longitudinal set 33 healthy pregnant women were analyzed at three different time points throughout gestation and one postpartum. Study Group B: Cross-sectionally additional 56 patients were enrolled. We compared patients with PE (N = 14) and IUGR (N = 14) with gestational age matched healthy controls (CTRL = 28). Group A: The apparent 11β-HSD2 activity dropped in the second trimester being restored to first trimester levels (P value = 0.016). Group B: The 11β-HSD2 activity was high in PE (P value < 0.05) but not in the IUGR group as compared to CTRL. The increased apparent serum 11β-HSD2 activity observed with advancing gestation in normal pregnancy may reflect an elevated general increase in enzyme activity due to a higher placental mass. The high systemic 11β-HSD2 activity in PE but not in IUGR however suggests an increased F deactivation in maternal tissue in PE rather than in the placenta since placental insufficiency in the absence of PE does not significantly alter F/E ratio.

Comparative profiling of adrenal steroids in maternal and umbilical cord blood

Fetal steroidome in late pregnancy receives multiple contributions from both maternal and fetal adrenals as well as from placenta. Depressed glucocorticoid levels have been reported in fetal blood at birth, yet studies on mineralocorticoid pathways are sparse. To investigate biosynthesis pathways at birth, adrenal steroids profiles were established in paired mothers and neonates. Forty-six paired healthy term newborns and their mothers from the Aldo cohort were assessed. Steroidomic profiles of mineralocorticoids, glucocorticoids and adrenal androgens were established from umbilical cord and maternal blood at birth using a highly sensitive and specific LC–MS/MS methodology. As compared to maternal blood, umbilical cord blood exhibited high levels of steroids precursors (progesterone and 11-deoxycorticosterone) contrasting with a collapse in corticosterone levels. Consecutively, 18-hydroxycorticosterone and aldosterone levels were also depressed in neonates. Similarly, umbilical cord blood levels of both 17-hydroxyprogesterone and 11-deoxycortisol were higher while cortisol levels sharply decreased. The product-to-substrate ratios evaluating the 11-hydroxylation step (corticosterone/11-deoxycorticosterone and cortisol/11-deoxycortisol) fell for both pathways. As expected, cortisone and 11-dehydrocorticosterone levels exceed those of cortisol and corticosterone in umbilical cord blood reflecting the strong placental 11-β-hydroxysteroid-dehydrogenase type 2 (11βHSD2) activity. Dehydroepiandrosterone-sulphate levels are higher in neonates, while both androstenedione and testosterone levels sharply fell. No significant difference in steroid levels could be observed according the gender except higher testosterone concentrations in umbilical cord of boys. Moreover, a strong and negative relationship between testosterone and progesterone levels was recorded in umbilical cord of boys. These adrenal steroidomic profiling demonstrate a deficit in mineralocorticoids (aldosterone, 18-hydroxycorticosterone and corticosterone) and glucocorticoids (cortisol) in term neonates, reflecting either a relative defect in 11-hydroxylase activity or more likely the strong placental 11-β-HSD2 activity. Collectively, these findings should be taken into account for a better understanding of regulatory interactions between placenta and fetal adrenal.

Transfer and Metabolism of Cortisol by the Isolated Perfused Human Placenta.

Context:Fetal overexposure to glucocorticoids in utero is associated with fetal growth restriction and is postulated to be a key mechanism linking suboptimal fetal growth with cardiovascular disease in later life.Objective:To develop a model to predict maternal-fetal glucocorticoid transfer. We hypothesized placental 11-β-hydroxysteroid dehydrogenase-type 2 (11β-HSD2) would be the major rate-limiting step in maternal cortisol transfer to the fetus.Design:We used a deuterated cortisol tracer in the ex vivo placental perfusion model, in combination with computational modeling, to investigate the role of interconversion of cortisol and its inactive metabolite cortisone on transfer of cortisol from mother to fetus.Participants:Term placentas were collected from five women with uncomplicated pregnancies, at elective caesarean delivery.Intervention:Maternal artery of the isolated perfused placenta was perfused with D4-cortisol.Main Outcome Measures:D4-cortisol, D3-cortisone, and D3-cortisol were measured in maternal and fetal venous outflows.Results:D4-cortisol, D3-cortisone, and D3-cortisol were detected and increased in maternal and fetal veins as the concentration of D4-cortisol perfusion increased. D3-cortisone synthesis was inhibited when 11-β-hydroxysteroid dehydrogenase (11β-HSD) activity was inhibited. At the highest inlet concentration, only 3.0% of the maternal cortisol was transferred to the fetal circulation, whereas 26.5% was metabolized and 70.5% exited via the maternal vein. Inhibiting 11β-HSD activity increased the transfer to the fetus to 7.3% of the maternal input, whereas 92.7% exited via the maternal vein.Conclusions:Our findings challenge the concept that maternal cortisol diffuses freely across the placenta and confirm that 11β-HSD2 acts as a major “barrier” to cortisol transfer to the fetus.

Topical 11β-Hydroxysteroid Dehydrogenase Type 1 Inhibition Corrects Cutaneous Features of Systemic Glucocorticoid Excess in Female Mice.

Glucocorticoid (GC) excess drives multiple cutaneous adverse effects, including skin thinning and poor wound healing. The ubiquitously expressed enzyme 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) activates mouse corticosterone from 11-dehydrocorticosterone (and human cortisol from cortisone). We previously demonstrated elevated 11β-HSD1 activity during mouse wound healing, but the interplay between cutaneous 11β-HSD1 and systemic GC excess is unexplored. Here, we examined effects of 11β-HSD1 inhibition by carbenoxolone (CBX) in mice treated with corticosterone (CORT) or vehicle for 6 weeks. Mice were treated bidaily with topical CBX or vehicle (VEH) 7 days before wounding and during wound healing. CORT mice displayed skin thinning and impaired wound healing but also increased epidermal integrity. 11β-HSD1 activity was elevated in unwounded CORT skin and was inhibited by CBX. CORT mice treated with CBX displayed 51%, 59%, and 100% normalization of wound healing, epidermal thickness, and epidermal integrity, respectively. Gene expression studies revealed normalization of interleukin 6, keratinocyte growth factor, collagen 1, collagen 3, matrix metalloproteinase 9, and tissue inhibitor of matrix metalloproteinase 4 by CBX during wound healing. Importantly, proinflammatory cytokine expression and resolution of inflammation were unaffected by 11β-HSD1 inhibition. CBX did not regulate skin function or wound healing in the absence of CORT. Our findings demonstrate that 11β-HSD1 inhibition can limit the cutaneous effects of GC excess, which may improve the safety profile of systemic steroids and the prognosis of chronic wounds.

An insight into the possible mechanisms of antispermatogenic action of Dalbergia sissoo in male mice.

This study investigated the possible mechanisms of antispermatogenic action of Dalbergia sissoo in Parkes male mice. Mice were orally administered aqueous leaf extract of Dalbergia sissoo (50 and 100mg kg-1 body weight day-1 for 35days) and various testicular indices such 3β- and 17β-hydroxysteroid dehydrogenase (HSD) activities, Western blot analyses of StAR, cytochrome P450scc and caspase-3, germ cell apoptosis by TUNEL, and lipid peroxidation and antioxidant enzymes activities were assessed. A significant increase in lipid peroxidation level and a marked decrease in activities of superoxide dismutase, catalase, 3β- and 17β-HSD were noted in the testis of Dalbergia-treated mice compared to controls. The treatment also had adverse effect on expression levels of StAR and cytochrome P450scc in the testis. There was an increase in the number of TUNEL-positive germ cells and in expression level of caspase-3 in testes of Dalbergia-treated mice, especially in those treated with 100mg dose compared to controls. By 56days of withdrawal therapy, the alterations induced in the above parameters recovered to control levels. Our results thus suggest that Dalbergia treatment interferes with steroidogenesis and produces oxidative stress in the testis, which may induce germ cell apoptosis leading to suppression of spermatogenesis.

Steroidogenic enzyme activities in the pre- and post-parturient equine placenta.

Steroidogenic enzymes in placentas shape steroid hormone profiles in the maternal circulation of each mammalian species. These include 3β-hydroxysteroid dehydrogenase/Δ5-4 isomerase (3βHSD) and 17α-hydroxylase/17,20-lyase cytochrome P450 (P450c17) crucial for progesterone and androgen synthesis, respectively, as well as aromatase cytochrome P450 (P450arom) that converts Δ4-androgens to estrogens. 5α-reductase is another important enzyme in equine placentas because 5α-dihydroprogesterone (DHP) sustains pregnancy in the absence of progesterone in the second half of equine pregnancy. DHP and its metabolites decline dramatically days before foaling, but few studies have investigated placental enzyme activity before or at parturition in mares. Thus, key enzyme activities and transcript abundance were investigated in equine placentas at 300 days of gestation (GD300) and post-partum (term). Equine testis was used as a positive control for P450c17 activity. Substrates were incubated with microsomal preparations, together with enzyme inhibitors, and products were measured by liquid chromatography tandem mass spectrometry or radiometric methods (aromatase). Equine placenta expressed high levels of 3βHSD, 5α-reductase and aromatase, and minimal P450c17 activity at GD300 compared with testis (600-fold higher). At foaling, 3βHSD and aromatase activities and transcript abundance were unchanged but 5α-reductase (and P450c17) was no longer detectable (P < 0.05) and transcript was decreased. Trilostane inhibited 3βHSD significantly more in testis than placenta, suggesting possible existence of different 3βHSD isoforms. Equine placentas have significant capacity for steroid metabolism by 5α-reductase, 3βHSD and aromatase but little for androgen synthesis lacking P450c17. Declining pre-partum 5α-reduced pregnane concentrations coincide with selective loss of placental 5α-reductase activity and expression at parturition in horses.

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.

3β-HSD expression in the CNS of a manakin and finch

The prohormone, dehydroepiandrosterone (DHEA) circulates in vertebrate blood with the potential for actions on target tissues including the central nervous system (CNS). Many actions of DHEA require its conversion into more active products, some of which are catalyzed by the enzyme 3β-hydroxysteroid-dehydrogenase/isomerase (3β-HSD). Studies of birds show both expression and activity of 3β-HSD in brain and its importance in regulating social behavior. In oscine songbirds, 3β-HSD is expressed at reasonably high levels in brain, possibly linked to their complex neural circuitry controlling song. Studies also indicate that circulating DHEA may serve as the substrate for neural 3β-HSD to produce active steroids that activate behavior during non-breeding seasons. In the golden-collared manakin (Manacus vitellinus), a sub-oscine bird, low levels of courtship behavior are displayed by males when circulating testosterone levels are basal. Therefore, we asked whether DHEA circulates in blood of manakins and whether the brain expresses 3β-HSD mRNA. Given that the spinal cord is a target of androgens and likely important in regulating acrobatic movements, we also examined expression of this enzyme in the manakin spinal cord. For comparison, we examined expression levels with those of an oscine songbird, the zebra finch (Taeniopygia guttata), a species in which brain, but not spinal cord, 3β-HSD has been well studied. DHEA was detected in manakin blood at levels similar to that seen in other species. As described previously, 3β-HSD was expressed in all zebra finch brain regions examined. By contrast, expression of 3β-HSD was only detected in the manakin hypothalamus where levels were greater than zebra finches. In spinal cord, 3β-HSD was detected in some but not all regions in both species. These data point to species differences and indicate that manakins have the substrate and neural machinery to convert circulating DHEA into potentially active androgens and/or estrogens.

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.

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

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

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.

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.

Effect of quercetin on cadmium chloride-induced impairments in sexual behaviour and steroidogenesis in male Wistar rats.

Cadmium chloride (CdCl2 ) has been reported to cause reproductive toxicity in male rats, mainly through oxidative stress. This study examined its effect on sexual behaviour, as one of the mechanisms of reproductive dysfunction, as well as the possible ameliorative effect of quercetin (QE) on same. Thirty male Wistar rats (10weeks old), weighing 270-300g, were used for this study. They were either orally administered 2% DMSO, CdCl2 (5mg/kg b.w.), QE (20mg/kg b.w.) or CdCl2 +QE, once daily for 4weeks, before sexual behavioural studies. The 5th group received CdCl2 for 4weeks and allowed 4-week recovery period, before sexual behavioural test. Rats were sacrificed after sexual behavioural studies. The blood, testis and penis were collected for biochemical assays. Cadmium increased mount, intromission and ejaculatory latencies, but reduced their frequencies, compared to control. Serum nitric oxide increased, while penile cyclic guanosine monophosphate reduced in the CdCl2 -exposed rats, compared to control. CdCl2 increased testicular cholesterol, but reduced 3β-hydroxysteroid dehydrogenase (3β-HSD) and 17β-HSD activities, and testosterone concentration. QE better attenuated these negative changes compared to withdrawal of CdCl2 treatment. In conclusion, CdCl2 suppressed steroidogenesis, penile erection and sexual behaviour, with poor reversal following withdrawal, while QE attenuated these effects.

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.

T-cell autonomous death induced by regeneration of inert glucocorticoid metabolites

Glucocorticoids (GC) are essential regulators of T-cell development and function. Activation of the immune system increases systemic adrenal-derived GC levels which downregulate immune activity as part of a negative feedback control system. Increasing evidence shows, however, that GC can also be derived from extra-adrenal sources such as the thymus or intestine, thus providing local control of GC-mediated effects. The thymus reportedly produces GC, but whether thymic epithelial cells or thymocytes produce GC acting either in an autocrine or paracrine fashion is not clear. We studied the expression of two main enzymes involved in de novo GC synthesis, CYP11A1 and CYP11B1, as well as the expression and activity of HSD11B1, an enzyme catalyzing interconversion of inert GC metabolites with active GC. While we found no evidence of de novo GC synthesis in both thymocytes and peripheral T cells, abundant regeneration of GC from the inactive metabolite 11-dehydrocorticosterone was detectable. Irrespective of their maturation stage, T cells that produced GC in this manner undergo autonomous cell death as this was blocked when glucocorticoid receptor-deficient T cells were treated with GC metabolites. These results indicate that both immature and mature T cells possess the capacity to undergo apoptosis in response to intrinsically generated GC. Consequently, positive selection of thymocytes, as well as survival of peripheral T cells may depend on TCR-induced escape of otherwise HSD11B1-driven autonomous T-cell death.

11 beta-hydroxysteroid dehydrogenase 2 promoter methylation is associated with placental protein expression in small for gestational age newborns

Small for gestational age infants have greater risk of developing metabolic diseases in adult life. It has been suggested that low birth weight may result from glucocorticoid excess in utero, a key mechanism in fetal programming. The placental enzyme 11-beta hydroxysteroid dehydrogenase type 2 (11β-HSD2, HSD11B2 gene) acts as a barrier protecting the fetus from maternal corticosteroid deleterious effects. Low placental 11β-HSD2 transcription and activity have been associated with low birth weight, yet the mechanism regulating its protein expression is not fully understood. In the present study we aimed to analyze 11β-HSD2 protein expression in placentas of adequate and small for gestational age (AGA and SGA, respectively) newborns from healthy mothers, and to explore whether 11β-HSD2 protein expression could be modulated by DNA methylation. 11β-HSD2 protein levels were measured by western blot in placental biopsies from term AGA and SGA infants (n=10 per group). DNA methylation was profiled both globally and in the HSD11B2 promoter by liquid chromatography with UV detection and methylation-specific melting curve analysis, respectively. We found lower placental 11β-HSD2 protein expression and higher HSD11B2 promoter methylation in SGA compared to AGA. Promoter methylation was inversely correlated with both protein expression and, importantly, birth weight. No changes in global placental methylation were found. In conclusion, lower 11β-HSD2 protein expression is associated with higher HSD11B2 promoter methylation, correlating with birth weight in healthy pregnancy. Our data support the role of 11β-HSD2 in determining birth weight, providing evidence of its regulation by epigenetic mechanisms, which may affect postnatal metabolic disease risk.