Chalcones from plants cause toxicity by inhibiting human and rat 11ß-hydroxysteroid dehydrogenase 2: 3D-quantitative structure-activity relationship (3D-QSAR) and in silico docking analysis.

Chalcones from licorice and its related plants have many pharmacological effects. However, the effects of chalcones on the activity of human and rat 11ß-hydroxysteroid dehydrogenase 2 (11ß-HSD2), and associated side effects remain unclear. The inhibition of 11 chalcones on human and rat 11ß-HSD2 were evaluated in microsomes and a 3D-quantitative structure-activity relationship (3D-QSAR) was analyzed. Screening revealed that bavachalcone, echinatin, isobavachalcone, isobavachromene, isoliquiritigenin, licochalcone A, and licochalcone B significantly inhibited human 11ß-HSD2 with IC50 values ranging from 15.62 (licochalcone A) to 38.33 (echinatin) µM. Screening showed that the above chemicals and 4-hydroxychalcone significantly inhibited rat 11ß-HSD2 with IC50 values ranging from 6.82 (isobavachalcone) to 72.26 (4-hydroxychalcone) µM. These chalcones acted as noncompetitive/mixed inhibitors for both enzymes. Comparative analysis revealed that inhibition of 11ß-HSD2 depended on the species. Most chemicals bind to the NAD+ binding site or both the NAD+ and substrate binding sites. Bivariate correlation analysis showed that lipophilicity and molecular weight determine inhibitory strength. Through our 3D-QSAR models, we identified that the hydrophobic region, hydrophobic aliphatic groups, and hydrogen bond acceptors are pivotal factors in inhibiting 11ß-HSD2. In conclusion, many chalcones inhibit human and rat 11ß-HSD2, possibly causing side effects and there is structure-dependent and species-dependent inhibition on 11ß-HSD2.

Structure-activity relationship and docking analysis of nature flavonoids as inhibitors of human and rat gonadal 3ß-hydroxysteroid dehydrogenases for therapeutic purposes.

The potential inhibitory effects of flavonoids on gonadal steroid biosynthesis have gained attention due to their widespread presence in natural plant sources. Specifically, our study focused on evaluating the inhibitory efficacy of these compounds on human 3ß-hydroxysteroid dehydrogenase 2 (h3ß-HSD2) and rat homolog r3ß-HSD1, enzymes responsible for the conversion of pregnenolone to progesterone. Through our investigations, we observed that the potency of flavonoids was silymarin (IC50, 1.31 µM) > luteolin (4.63 µM) > tectorigenin > (5.86 µM), and rutin (44.12 µM) in inhibiting human KGN cell microsomal h3ß-HSD2. Similarly, the potency of flavonoids was silymarin (9.50 µM) > luteolin (11.49 µM) > tectorigenin (14.06 µM), and rutin (145.71 µM) in inhibiting rat testicular r3ß-HSD1. Silymarin, luteolin, and tectorigenin acted as mixed inhibitors of both human and rat 3ß-HSDs. Luteolin and tectorigenin were able to penetrate human KGN cells to inhibit progesterone secretion. Furthermore, docking analysis and structure-activity relationship analysis highlighted the importance of hydrogen bond formation for the inhibitory efficacy of these compounds against h3ß-HSD2 and r3ß-HSD1. Overall, this study demonstrates that silymarin exhibits the most potent inhibition of human and rat gonadal 3ß-HSDs, and significant SAR differences exist among the tested compounds.

Pseudohypoadrenalism, a subclinical cortisol metabolism disorder in hyperuricemia.

Background: Hyperuricemia is a known risk factor of lipid metabolism disorder. However, the mechanisms have not been fully understood. Methods: The serum samples from hyperuricemia subjects were used to analyze the correlation between serum uric acid and clinical characteristics. Hyperuricemia mice induced by potassium oxonate (PO) and adenine were used to explore glucocorticoid metabolism. Results: In hyperuricemia patients, the levels of serum uric acid were positively correlated with the levels of γ-glutamyltransferase, associated with a cortisol metabolism disorder. In hyperuricemia state, the adrenal glands failed to respond to adrenocorticotropic hormone properly, leading to low cortisol, but not corticosterone production, and decreased mRNA levels of aldosterone synthase, 11ß-hydroxylase, and 3ß-hydroxysteroid dehydrogenase 1, three key enzymes for cortisol synthesis. The expression of both hepatic 5α-reductase and renal 11ß-hydroxysteroid dehydrogenase 2 was significantly reduced, which led to low cortisol clearance. We denominated this cortisol metabolism disorder in hyperuricemia as pseudohypoadrenalism (PHAL). Conclusion: PHAL increased exposure to the bioavailable cortisol in the liver, leading to local amplification of the biological action of corticosteroids. Unregulated biosynthesis pathway of bile acid expanded bile acid pool, and further aggravated cholestatic liver injury.

Predisposing factors for adrenal crisis in chronic adrenal insufficiency: a case-control study.

OBJECTIVE: This study aims to identify susceptibility markers for adrenal crises (AC) in educated patients with chronic adrenal insufficiency (AI). DESIGN: A case-control study involving 66 patients with AI analyzing the impact of glucocorticoid and mineralocorticoid exposure, adrenomedullary function, inflammatory parameters, and educational status on AC frequency. Patients were categorized into low (n = 32) and high (n = 34) AC frequency groups based on AC occurrence (below or 2 times above the average of the reported AC frequency of 8.3 AC/100 patient-years in a previous prospective study). METHODS: Parameters, including cortisol plasma profile and urinary steroid excretion after administration of the morning glucocorticoid dose, 24-h urinary steroid profiling, salivary cortisol profiling, and hair cortisol, estimated cortisol exposure. Polymorphisms (single nucleotide polymorphism [SNP]) of the glucocorticoid receptor (NR3C1) and mineralocorticoid receptor (NR3C2) associated with individual steroid sensitivity were assessed together with SNPs for 11ß-hydroxysteroid dehydrogenase 1 (HSD11B1) and 11ß-hydroxysteroid dehydrogenase 2 (HSD11B2). Mineralocorticoid replacement was evaluated by serum and urinary electrolytes and osmolality, plasma-renin concentration, and ambulatory blood pressure levels. We additionally measured plasma and urinary catecholamines, serum levels of IL6 and hsCRP, and SNPs of IL6 and TNF-alpha. Patient knowledge of AC prevention was assessed by questionnaires. RESULTS: Frequent AC patients had higher daily glucocorticoid doses and hair cortisol levels, with no significant differences in other parameters investigated. AC frequency is inversely correlated with the frequency of self-reported adjustments of the glucocorticoid replacement. CONCLUSION: Higher glucocorticoid dosages in high-risk patients, despite unaffected cortisol metabolism, may be linked to decreased cortisol sensitivity or impaired glucocorticoid absorption. Proactive dose adjustments show a protective effect against AC, regardless of biological vulnerability.

Resistance to Resveratrol Treatment in Experimental PTSD Is Associated with Abnormalities in Hepatic Metabolism of Glucocorticoids.

Glucocorticoids are metabolized by the CYP3A isoform of cytochrome P450 and by 11-ß-hydroxysteroid dehydrogenase type 1 (11ß-HSD-1). Experimental data suggest that post-traumatic stress disorder (PTSD) is associated with an increase in hepatic 11ß-HSD-1 activity and a concomitant decrease in hepatic CYP3A activity. Trans-resveratrol, a natural polyphenol, has been extensively studied for its antipsychiatric properties. Recently, protective effects of trans-resveratrol were found in relation to PTSD. Treatment of PTSD rats with trans-resveratrol allowed the rats to be divided into two phenotypes. The first phenotype is treatment-sensitive rats (TSR), and the second phenotype is treatment-resistant rats (TRRs). In TSR rats, trans-resveratrol ameliorated anxiety-like behavior and reversed plasma corticosterone concentration abnormalities. In contrast, in TRR rats, trans-resveratrol aggravated anxiety-like behavior and decreased plasma corticosterone concentration. In TSR rats, hepatic 11ß-HSD-1 activity was suppressed, with a concomitant increase in CYP3A activity. In TRR rats, the activities of both enzymes were suppressed. Thus, the resistance of PTSD rats to trans-resveratrol treatment is associated with abnormalities in hepatic metabolism of glucocorticoids. The free energy of binding of resveratrol, cortisol, and corticosterone to the human CYP3A protein was determined using the molecular mechanics Poisson-Boltzmann surface area approach, indicating that resveratrol could affect CYP3A activity.

Direct inhibition of human and rat 11ß-hydroxysteroid dehydrogenase 2 by per- and polyfluoroalkyl substances: Structure-activity relationship and in silico docking analysis.

Per- and polyfluoroalkyl substances (PFAS) are persistent in the environment and may disrupt the endocrine system. Our previous study showed that perfluorooctanoic acid (PFOA, C8) and perfluorooctanesulfonic acid (PFOS, C8S) can inhibit 11ß-hydroxysteroid dehydrogenase 2 (11ß-HSD2) activity leading to an active glucocorticoid accumulation. In this study, we extended investigation for 17 PFAS, including carboxylic and sulfonic acids, with different carbon-chain lengths, to determine their inhibitory potency and structure-activity relationship in human placental and rat renal 11ß-HSD2. C8-C14 PFAS at 100 µM significantly inhibited human 11ß-HSD2 with a potency as C10 (half-maximal inhibitory concentration, IC50, 9.19 µM) > C11 (15.09 µM) > C12 (18.43 µM) > C9 (20.93 µM) > C13 (124 µM) > C14 (147.3 µM) > other C4-C7 carboxylic acids, and C8S > C7S = C10S > other sulfonic acids. For rat 11ß-HSD2, only C9 and C10 and C7S and C8S PFAS exhibited significant inhibitory effects. PFAS are primarily mixed/competitive inhibitors of human 11ß-HSD2. Preincubation and simultaneous incubation with the reducing agent dithiothreitol significantly increased human 11ß-HSD2 but not rat 11ß-HSD2, and preincubation but not simultaneous incubation with dithiothreitol partially reversed C10-mediated inhibition on human 11ß-HSD2. Docking analysis showed that all PFAS bound to the steroid-binding site and carbon-chain length determined the potency of inhibition, with the optimal molecular length (12.6 Å) for potent inhibitors PFDA and PFOS, which is comparable to the molecular length (12.7 Å) of the substrate cortisol. The length between 8.9 and 17.2 Å is the probable threshold molecular length to inhibit human 11ß-HSD2. In conclusion, the carbon-chain length determines the inhibitory effect of PFAS on human and rat 11ß-HSD2, and the inhibitory potency of long-chain PFAS on human and rat 11ß-HSD2 showed V-shaped pattern. Long-chain PFAS may partially act on the cysteine residues of human 11ß-HSD2.

Direct inhibition of bisphenols on human and rat 11ß-hydroxysteroid dehydrogenase 2: Structure-activity relationship and docking analysis.

Bisphenols (BPs) as endocrine-disrupting compounds have drawn attention to their health hazards. Whether a BP interferes with glucocorticoid metabolism remains unclear. 11ß-Hydroxysteroid dehydrogenase 2 (11ß-HSD2) is a key glucocorticoid-metabolizing enzyme that controls fetal glucocorticoid levels across the placental barrier and mineralocorticoid receptor specificity in the kidney. In this study, 11 BPs were tested to inhibit human placental and rat renal 11ß-HSD2 and were analyzed for inhibitory potency, mode action, and docking parameters. BPs had inhibitory potency against human 11ß-HSD2: BPFL>BPAP>BPZ>BPB>BPC>BPAF>BPA>TDP and the IC10 values were 0.21, 0.55, 1.04, 2.04, 2.43, 2.57, 14.43, and 22.18 µM, respectively. All BPs are mixed inhibitors except BPAP, which is a competitive inhibitor for human 11ß-HSD2. Some BPs also inhibited rat renal 11ß-HSD2, with BPB (IC50, 27.74 ± 0.95) > BPZ (42.14 ± 0.59) > BPAF (54.87 ± 1.73) > BPA (77.32 ± 1.20) > other BPs (about 100 µM). Docking analysis showed that all BPs bound to the steroid-binding site, interacting with the catalytic residue Tyr232 of both enzymes and the most potent human 11ß-HSD2 inhibitor BPFL acts possibly due to its large fluorene ring that has hydrophobic interaction with residues Glu172 and Val270 and π-stacking interaction with catalytic residue Tyr232. The increase in the size of substituted alkanes and halogenated groups in the methane moiety of the bridge of BPs increases its inhibitory potency. Regressions of the lowest binding energy with inhibition constant indicated that there was an inverse regression. These results indicated that BPs significantly inhibited human and rat 11ß-HSD2 activity and that there were species-dependent differences.

Halogen atoms determine the inhibitory potency of halogenated bisphenol A derivatives on human and rat placental 11ß-hydroxysteroid dehydrogenase 2.

Some halogenated bisphenol A (BPA) derivatives (tetrabromobisphenol A, TBBPA, and tetrachlorobisphenol A, TCBPA) are produced in a high volume and exist in PM2.5 after waste burning. 11ß-Hydroxysteroid dehydrogenase 2 (11ß-HSD2) is a critical enzyme for placental function. However, whether halogenated bisphenols inhibit 11ß-HSD2 and the mode of action remains unclear. The objective of this study was to investigate BPA derivatives on human and rat placental 11ß-HSD2. The inhibitory strength on human 11ß-HSD2 was TBBPA (IC50, 0.665 µM)>TCBPA (2.22 µM)>trichloro BPA (TrCBPA, 19.87 µM)>tetrabromobisphenol S (TBBPS, 36.76 µM)>monochloro BPA (MCBPA, 104.0 µM)>BPA (144.9 µM)>bisphenol S. All chemicals are mixed and competitive inhibitors. Rat 11ß-HSD2 was less sensitive to BPA derivatives, with TBBPA (IC50, 96.63 µM)>TCBPA (99.69 µM)>TrCBPA (104.1 µM)>BPA (117.1 µM)>others. Docking analysis showed that BPA derivatives bind steroid active sites. Structure-activity relationship revealed that halogen atoms and LogP were inversely correlated with inhibitory strength on human 11ß-HSD2, while LogS and polar desolvation energy were positively correlated with the inhibitory strength. In conclusion, halogenated BPA derivatives are mostly potent inhibitors on human 11ß-HSD2 and there is structure-dependent inhibition.

The effect of cold exposure on the levels of glucocorticoids, 11-hydroxysteroid dehydrogenase 2, and placental vascularization in a rat model.

OBJECTIVE: Cold exposure (CE) before birth is one of the initial stressors that may impact mammalian pregnancy, changing placental and fetal development and affecting the health of the offspring. While glucocorticoids (GCs) participate in the body's response to the stress of CE, the specific mechanisms of their action are unclear. This study aims to determine the effect of CE stress on the placenta and to test whether stress, caused by cold exposure in pregnancy impairs fetal development by changing placental angiogenesis via excessive GC expression. MATERIALS AND METHODS: CE rat model was created by exposing 30 SD rats to cold preconception, or during the first, second, and third weeks of pregnancy. Serum cortisol and soluble fms-like tyrosine kinase-1 (sFlt-1) expression levels, physiological index changes (food intake, body weight change and blood pressure), and pregnancy outcomes (fetal rat weight, number of live fetal rats, and placental weight) were collected at baseline and at different time points after the conception. Protein expression levels of 11 ß-hydroxysteroid dehydrogenase 2 (11ß-HSD2), glucocorticoid receptor, vascular endothelial growth factor A (VEGF-A), placental growth factor (PIGF), and sFlt-1 in placental tissues were measured by western blotting. Cytokeratin (CK) and laminin (LN) in trophoblasts, and α-actin in vascular smooth muscle of the spiral arteries of pregnant rats after the systemic cold treatment were assessed by immunofluorescence and visualized by fluorescent microscopy. To test the effect of 11ß-HSD2 levels on the placental recasting, human first-trimester extravillous trophoblast cells (HTR8/SVneo) underwent knockdown using specific 11ß-HSD2 siRNA constructs.  Expression levels of 11ß-HSD2 were analyzed by quantitative real-time PCR (qPCR) and into HTR8 cells, and the expression levels of the 11ß-HSD2 gene in each group were measured using qPCR. Cell migration and invasion was assessed by Transwell migration assay, and sFlt-1 levels in HTR8 cells were measured by ELISA. RESULTS: CE pre-conception led to consistently increasing serum corticosterone and sFlt-1 levels throughout pregnancy, and persistently increased diastolic blood pressure (DBP) in rat CE model compared to control animals. CE during the second week of gestation (Gp.3) was associated with significantly lower placental weight (p=0.0003). Cold exposure in the third week (Gp.4) was associated with significantly (p=0.001) lower fetal weight. CE pre-conception was associated with significantly decreased placental levels of 11ß-HSD2, glucocorticoid receptor, VEGF-A, PIGF, and sFlt-1 proteins and α-actin compared to the control group. Silencing 11ß-HSD2 by siRNA led to reduced cell migrations and invasion, and markedly increased expression levels of sFlt-1 in HTR8/SVneo cells (p<0.05). CONCLUSIONS: Pre-conception cold exposure and during early pregnancy leads to increased GCs levels and impaired placental 11ß-HSD2 activity. We suggest that the subsequent 11ß-HSD2-induced increase in the sFlt-1expression during early pregnancy may affect placental vascular remodeling and change placental morphological structure and function.

C11-hydroxy and C11-oxo C19 and C21 Steroids: Pre-Receptor Regulation and Interaction with Androgen and Progesterone Steroid Receptors.

C11-oxy C19 and C11-oxy C21 steroids have been identified as novel steroids but their function remains unclear. This study aimed to investigate the pre-receptor regulation of C11-oxy steroids by 11ß-hydroxysteroid dehydrogenase (11ßHSD) interconversion and potential agonist and antagonist activity associated with the androgen (AR) and progesterone receptors (PRA and PRB). Steroid conversions were investigated in transiently transfected HEK293 cells expressing 11ßHSD1 and 11ßHSD2, while CV1 cells were utilised for agonist and antagonist assays. The conversion of C11-hydroxy steroids to C11-oxo steroids by 11ßHSD2 occurred more readily than the reverse reaction catalysed by 11ßHSD1, while the interconversion of C11-oxy C19 steroids was more efficient than C11-oxy C21 steroids. Furthermore, 11-ketodihydrotestosterone (11KDHT), 11-ketotestosterone (11KT) and 11ß-hydroxydihydrotestosterone (11OHDHT) were AR agonists, while only progestogens, 11ß-hydroxyprogesterone (11ßOHP4), 11ß-hydroxydihydroprogesterone (11ßOHDHP4), 11α-hydroxyprogesterone (11αOHP4), 11α-hydroxydihydroprogesterone (11αOHDHP4), 11-ketoprogesterone (11KP4), 5α-pregnan-17α-diol-3,11,20-trione (11KPdione) and 21-deoxycortisone (21dE) exhibited antagonist activity. C11-hydroxy C21 steroids, 11ßOHP4, 11ßOHDHP4 and 11αOHP4 exhibited PRA and PRB agonistic activity, while only C11-oxo steroids, 11KP4 and 11-ketoandrostanediol (11K3αdiol) demonstrated PRB agonism. While no steroids antagonised the PRA, 11OHA4, 11ß-hydroxytestosterone (11OHT), 11KT and 11KDHT exhibited PRB antagonism. The regulatory role of 11ßHSD isozymes impacting receptor activation is clear-C11-oxo androgens exhibit AR agonist activity; only C11-hydroxy progestogens exhibit PRA and PRB agonist activity. Regulation by the downstream metabolites of active C11-oxy steroids at the receptor level is apparent-C11-hydroxy and C11-oxo metabolites antagonize the AR and PRB, progestogens the former, androgens the latter. The findings highlight the intricate interplay between receptors and active as well as "inactive" C11-oxy steroids, suggesting novel regulatory tiers.

Inhibition of 11ß-hydroxysteroid dehydrogenase 1 relieves fibrosis through depolarizing of hepatic stellate cell in NASH.

11ß-hydroxysteroid dehydrogenase type 1 (11ßHSD1) is a key enzyme that catalyzes the intracellular conversion of cortisone to physiologically active cortisol. Although 11ßHSD1 has been implicated in numerous metabolic syndromes, such as obesity and diabetes, the functional roles of 11ßHSD1 during progression of nonalcoholic steatohepatitis (NASH) and consequent fibrosis have not been fully elucidated. We found that pharmacological and genetic inhibition of 11ßHSD1 resulted in reprogramming of hepatic stellate cell (HSC) activation via inhibition of p-SMAD3, α-SMA, Snail, and Col1A1 in a fibrotic environment and in multicellular hepatic spheroids (MCHSs). We also determined that 11ßHSD1 contributes to the maintenance of NF-κB signaling through modulation of TNF, TLR7, ITGB3, and TWIST, as well as regulating PPARα signaling and extracellular matrix accumulation in activated HSCs during advanced fibrogenesis in MCHSs. Of great interest, the 11ßHSD1 inhibitor J2H-1702 significantly attenuated hepatic lipid accumulation and ameliorated liver fibrosis in diet- and toxicity-induced NASH mouse models. Together, our data indicate that J2H-1702 is a promising new clinical candidate for the treatment of NASH.

Cucumis melo var. momordica as a Potent Antidiabetic, Antioxidant and Possible Anticovid Alternative: Investigation through Experimental and Computational Methods.

Diabetes mellitus is a typical life threatening of disease, which generate due to the dysfunction of ß cells of pancreas. In 2014, WHO stated that 422 million people were infected with DM. The current pattern of management of diabetes included synthetic or plant based oral hypoglycemic drugs and insulin but drug resentence is become a very big issues in antidiabetic therapy. Thus, it's very earnest to discover now medication for this disease. Now the days, it is well acknowledged that diabetic patients are more prone towards covid and related complications. Thus, medical practitioners reformed the methodology of prescribing medication for covid infected antidiabetic therapy and encouraging the medication contains dual pharmacological properties. It is also well know that polyphenols specifically hold a significant role in oxidative stress and reduced the severity of many inflammatory diseases. Cucumis melo has rich history as ethano-pharmacological use in Indian subcontinent. The fruit and seed are well-known for the treatment of various diseases due to the presence of phenolics. Therefore, in this study, the combined mixture of flower and seeds were used for the extraction of polyphenolic rich extract and tested for antidiabetic activity through the antioxidant and in vivo experiments. The antioxidant potential measurement exhibited that the selected plant extract has the significant competence to down-regulate oxidative stress (DPPH scavenging IC50 at 60.7±1.05 µg/mL, ABTS IC50 at 62.15±0.50 µg/mL). Furthermore, the major polyphenolic phyto-compounds derived from the Cucumis melo were used for in silico anticovid activity, docking, and complementarity studies. The anticovid activity prognosis reflected that selected phyto-compounds amentoflavone and vanillic acid have optimal possibility to interact with 3C-like protease and through this moderate anticovid activity can be exhibit. The docking experiments established that the selected compounds have propensity to interact with protein tyrosine phosphatase 1B, 11ß-Hydroxysteroid dehydrogenase, superoxide dismutase, glutathione peroxidase, and catalase ß-glucuronidase receptor. In vivo experiments showed that 500 mg/kg, Cucumis melo extract ominously amplified body weight, plasma insulin, high-density lipoprotein levels, and biochemical markers. Furthermore, extract significantly downregulate the blood glucose, total cholesterol, triglycerides, low-density lipoprotein, and very low-density lipoprotein.

The Link between Activities of Hepatic 11beta-Hydroxysteroid Dehydrogenase-1 and Monoamine Oxidase-A in the Brain Following Repeated Predator Stress: Focus on Heightened Anxiety.

We investigated the presence of a molecular pathway from hepatic 11-ßHSD-1 to brain MAO-A in the dynamics of plasma corticosterone involvement in anxiety development. During 14 days following repeated exposure of rats to predator scent stress for 10 days, the following variables were measured: hepatic 11-ßHSD-1 and brain MAO-A activities, brain norepinephrine, plasma corticosterone concentrations, and anxiety, as reflected by performance on an elevated plus maze. Anxiety briefly decreased and then increased after stress exposure. This behavioral response correlated inversely with plasma corticosterone and with brain MAO-A activity. A mathematical model described the dynamics of the biochemical variables and predicted the factor(s) responsible for the development and dynamics of anxiety. In the model, hepatic 11-ßHSD-1 was considered a key factor in defining the dynamics of plasma corticosterone. In turn, plasma corticosterone and oxidation of brain ketodienes and conjugated trienes determined the dynamics of brain MAO-A activity, and MAO-A activity determined the dynamics of brain norepinephrine. Finally, plasma corticosterone was modeled as the determinant of anxiety. Solution of the model equations demonstrated that plasma corticosterone is mainly determined by the activity of hepatic 11-ßHSD-1 and, most importantly, that corticosterone plays a critical role in the dynamics of anxiety following repeated stress.

Interactions between nuclear receptors glucocorticoid receptor α and peroxisome proliferator-activated receptor α form a negative feedback loop.

Both nuclear receptors glucocorticoid receptor α (GRα) and peroxisome proliferator-activated receptor α (PPARα) are involved in energy and lipid metabolism, and possess anti-inflammation effects. Previous studies indicate that a regulatory loop may exist between them. In vivo and in vitro studies showed that glucocorticoids stimulate hepatic PPARα expression via GRα at the transcriptional level. This stimulation of PPARα by GRα has physiological relevance and PPARα is involved in many glucocorticoid-induced pathophysiological processes, including gluconeogenesis and ketogenesis during fasting, insulin resistance, hypertension and anti-inflammatory effects. PPARα also synergizes with GRα to promote erythroid progenitor self-renewal. As the feedback, PPARα inhibits glucocorticoid actions at pre-receptor and receptor levels. PPARα decreases glucocorticoid production through inhibiting the expression and activity of type-1 11ß-hydroxysteroid dehydrogenase, which converts inactive glucocorticoids to active glucocorticoids at local tissues, and also down-regulates hepatic GRα expression, thus forming a complete and negative feedback loop. This negative feedback loop sheds light on prospective multi-drug therapeutic treatments in inflammatory diseases through a combination of glucocorticoids and PPARα agonists. This combination may potentially enhance the anti-inflammatory effects while alleviating side effects on glucose and lipid metabolism due to GRα activation. More investigations are needed to clarify the underlying mechanism and the relevant physiological or pathological significance of this regulatory loop.

Differential expression of placental 11ß-HSD2 induced by high maternal glucocorticoid exposure mediates sex differences in placental and fetal development.

A variety of adverse environmental factors during pregnancy cause maternal chronic stress. Caffeine is a common stressor, and its consumption during pregnancy is widespread. Our previous study showed that prenatal caffeine exposure (PCE) increased maternal blood glucocorticoid levels and caused abnormal development of offspring. However, the placental mechanism for fetal development inhibition caused by PCE-induced high maternal glucocorticoid has not been reported. This study investigated the effects of PCE-induced high maternal glucocorticoid level on placental and fetal development by regulating placental 11ß-hydroxysteroid dehydrogenase 2 (11ß-HSD2) expression and its underlying mechanism. First, human placenta and umbilical cord blood samples were collected from women without prenatal use of synthetic glucocorticoids. We found that placental 11ß-HSD2 expression was significantly correlated with umbilical cord blood cortisol level and birth weight in male newborns but not in females. Furthermore, we established a rat model of high maternal glucocorticoids induced by PCE (caffeine, 60 mg/kg·d, ig), and found that the expression of 11ß-HSD2 in male PCE placenta was decreased and negatively correlated with the maternal/fetal/placental corticosterone levels. Meanwhile, we found abnormal placental structure and nutrient transporter expression. In vitro, BeWo cells were used and confirm that 11ß-HSD2 mediated inhibition of placental nutrient transporter expression induced by high levels of glucocorticoid. Finally, combined with the animal and cell experiments, we further confirmed that high maternal glucocorticoid could activate the GR-C/EBPα-Egr1 signaling pathway, leading to decreased expression of 11ß-HSD2 in males. However, there was no significant inhibition of placental 11ß-HSD2 expression, placental and fetal development in females. In summary, we confirmed that high maternal glucocorticoids could regulate placental 11ß-HSD2 expression in a sex-specific manner, leading to differences in placental and fetal development. This study provides the theoretical and experimental basis for analyzing the inhibition of fetoplacental development and its sex difference caused by maternal stress.

The role of mineralocorticoids and glucocorticoids under the impact of 11ß-hydroxysteroid dehydrogenase in human breast lesions.

We attempted to explore the possible involvement of the in situ availability of mineralocorticoids and mineralocorticoid receptor (MR) in the pathogenesis of mammary ductal carcinoma. We also explored their individual profiles among different subtypes of invasive ductal carcinomas of no special type (IDC-NST) by evaluating the status of MR, Glucocorticoid receptor (GR), and 11ß hydroxysteroid dehydrogenase (HSD) 1/2 at each stage of the putative cascade of the mammary ductal proliferative disorders. In this study, IDC-NST, ductal carcinoma in situ (DCIS), atypical ductal hyperplasia (ADH), and non-pathological breast tissues were all evaluated by immunohistochemistry. MR was significantly lower in ADH than in DCIS or IDC-NST. 11ßHSD2 was significantly lower in ADH than normal breast tissue and 11ßHSD1 was significantly higher in DCIS than normal, ADH, or IDC-NST. MR in progesterone receptor (PR)-positive IDC-NST cases tended to be associated with the Ki-67 labeling index. Results of the present study demonstrated that the status of MR and GR in conjunction with the 11ßHSDs was correlated with the development of low-grade proliferative disorders in mammary glands. In addition, the potential crosstalk between MR and PR could also influence cell proliferation of breast carcinoma cells but further investigations are required for clarification.

Steroid-converting enzymes in human adipose tissues and fat deposition with a focus on AKR1C enzymes.

Adipocytes express various enzymes, such as aldo-keto reductases (AKR1C), 11ß-hydroxysteroid dehydrogenase (11ß-HSD), aromatase, 5α-reductases, 3ß-HSD, and 17ß-HSDs involved in steroid hormone metabolism in adipose tissues. Increased activity of AKR1C enzymes and their expression in mature adipocytes might indicate the association of these enzymes with subcutaneous adipose tissue deposition. The inactivation of androgens by AKR1C enzymes increases adipogenesis and fat mass, particularly subcutaneous fat. AKR1C also causes reduction of estrone, a weak estrogen, to produce 17ß-estradiol, a potent estrogen and, in addition, it plays a role in progesterone metabolism. Functional impairments of adipose tissue and imbalance of steroid biosynthesis could lead to metabolic disturbances. In this review, we will focus on the enzymes involved in steroid metabolism and fat tissue deposition.

Endogenous Glucocorticoid Metabolism in Bone: Friend or Foe.

The role of tissue specific metabolism of endogenous glucocorticoids (GCs) in the pathogenesis of human disease has been a field of intense interest over the last 20 years, fuelling clinical trials of metabolism inhibitors in the treatment of an array of metabolic diseases. Localised pre-receptor metabolism of endogenous and therapeutic GCs by the 11ß-hydroxysteroid dehydrogenase (11ß-HSD) enzymes (which interconvert endogenous GCs between their inactive and active forms) are increasingly recognised as being critical in mediating both their positive and negative actions on bone homeostasis. In this review we explore the roles of endogenous and therapeutic GC metabolism by the 11ß-HSD enzymes in the context of bone metabolism and bone cell function, and consider future strategies aimed at modulating this system in order to manage and treat various bone diseases.

Modulation of 11ß-hydroxysteroid dehydrogenase functions by the cloud of endogenous metabolites in a local microenvironment: The glycyrrhetinic acid-like factor (GALF) hypothesis.

11ß-Hydroxysteroid dehydrogenase (11ß-HSD)-dependent conversion of cortisol to cortisone and corticosterone to 11-dehydrocorticosterone are essential in regulating transcriptional activities of mineralocorticoid receptors (MR) and glucocorticoid receptors (GR). Inhibition of 11ß-HSD by glycyrrhetinic acid metabolites, bioactive components of licorice, causes sodium retention and potassium loss, with hypertension characterized by low renin and aldosterone. Essential hypertension is a major disease, mostly with unknown underlying mechanisms. Here, we discuss a putative mechanism for essential hypertension, the concept that endogenous steroidal compounds acting as glycyrrhetinic acid-like factors (GALFs) inhibit 11ß-HSD dehydrogenase, and allow for glucocorticoid-induced MR and GR activation with resulting hypertension. Initially, several metabolites of adrenally produced glucocorticoids and mineralocorticoids were shown to be potent 11ß-HSD inhibitors. Such GALFs include modifications in the A-ring and/or at positions 3, 7 and 21 of the steroid backbone. These metabolites may be formed in peripheral tissues or by gut microbiota. More recently, metabolites of 11ß-hydroxy-Δ4androstene-3,17-dione and 7-oxygenated oxysterols have been identified as potent 11ß-HSD inhibitors. In a living system, 11ß-HSD isoforms are not exposed to a single substrate but to several substrates, cofactors, and various inhibitors simultaneously, all at different concentrations depending on physical state, tissue and cell type. We propose that this "cloud" of steroids and steroid-like substances in the microenvironment determines the 11ß-HSD-dependent control of MR and GR activity. A dysregulated composition of this cloud of metabolites in the respective microenvironment needs to be taken into account when investigating disease mechanisms, for forms of low renin, low aldosterone hypertension.

Cortisol induces follicle regression, while FSH prevents cortisol-induced follicle regression in pigs.

During follicular development, a few dominant follicles develop to large antral dominant follicles, whereas the remaining follicles undergo atretic degeneration. Because vascularization on the follicular surface is a morphological feature of dominant follicles, we previously classified these follicles as vascularized follicles (VFs) and non-VFs (NVFs). In NVFs, progesterone producing genes were expressed similarly to that in VFs; however, the progesterone concentration in follicular fluid was low in large NVFs. Therefore, we estimated that progesterone is converted to cortisol, which induces the loss of follicular functions. In this study, we comparative analyzed the expression of genes for progesterone converting enzymes (Cytochrome (CYP)11B1, CYP21A2, Hydroxysteroid (HSD)11B2) and cortisol receptor (NR3C1) in VF and NVF granulosa cells. In NVFs, expression of cortisol producing genes (CYP11B1 and CYP21A2) was higher than in VFs. Expression of the gene for the cortisol metabolizing enzyme HSD11B2 in NVFs was significantly lower than in VFs. In NVFs, accompanied by increasing cortisol concentration in follicular fluid, apoptosis of granulosa and cumulus cells was observed. Cultivation with FSH and metyrapone (a CYP11B1 inhibitor) of NVF cumulus-oocyte complexes inhibited apoptosis of cumulus cells and induced cumulus cell proliferation and oocyte maturation. Cortisol-induced CYP11B1 and CYP21A2 expression, whereas FSH-induced HSD11B2 mRNA expression in VF granulosa cells in the presence of cortisol. Furthermore, an addition of 18ß-glycyrrhetinic acid (18-GA; a HSD17B2 inhibitor) to cortisol and FSH-containing medium increased apoptosis of VF granulosa cells. These results suggested that cortisol is a stimulatory factor that induces follicular atresia; furthermore, inhibition of cortisol production by FSH might increase the number of healthy preovulatory follicles in pigs.