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Excessive glucocorticoid (GC) action is linked to various metabolic disorders. Recent findings suggest that disrupting skeletal GC signaling prevents bone loss and alleviates metabolic disorders in high-fat diet (HFD)-fed obese mice, underpinning the neglected contribution of skeletal GC action to obesity and related bone loss. Here, we show that the elevated expression of 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1), the enzyme driving local GC activation, and GC signaling in osteoblasts, are associated with bone loss and obesity in HFD-fed male mice. Osteoblast-specific 11β-HSD1 knockout male mice exhibit resistance to HFD-induced bone loss and metabolic disorders. Mechanistically, elevated 11β-HSD1 restrains glucose uptake and osteogenic activity in osteoblast. Pharmacologically inhibiting osteoblastic 11β-HSD1 by using bone-targeted 11β-HSD1 inhibitor markedly promotes bone formation, ameliorates glucose handling and mitigated obesity in HFD-fed male mice. Taken together, our study demonstrates that osteoblastic 11β-HSD1 directly contributes to HFD-induced bone loss, glucose handling impairment and obesity. Excessive glucocorticoid (GC) action is linked to various metabolic disorders. Here the authors show that elevated expression of 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1), the enzyme driving local bone GC activation, is associated with bone loss and obesity mice.

Abstract Aldo-keto reductases (AKRs) are monomeric NAD(P)(H)-dependent oxidoreductases that play pivotal roles in the biosynthesis and metabolism of steroids in humans. AKR1C enzymes acting as 3-ketosteroid, 17-ketosteroid, and 20-ketosteroid reductases are involved in the prereceptor regulation of ligands for the androgen, estrogen, and progesterone receptors and are considered drug targets to treat steroid hormone-dependent malignancies and endocrine disorders. In contrast, AKR1D1 is the only known steroid 5β-reductase and is essential for bile-acid biosynthesis, the generation of ligands for the farnesoid X receptor, and the 5β-dihydrosteroids that have their own biological activity. In this review we discuss the crystal structures of these AKRs, their kinetic and catalytic mechanisms, AKR genomics (gene expression, splice variants, polymorphic variants, and inherited genetic deficiencies), distribution in steroid target tissues, roles in steroid hormone action and disease, and inhibitor design.

Intracellular lipid droplets (LDs) are found in a wide variety of cell types and have been recognized as organelles with unique spherical structures. Although LDs are not stable lipid-depots, they are active sites of neutral lipid metabolism, and comprise neutral lipid or cholesterol cores surrounded by phospholipid monolayers containing specialized proteins. However, sizes and protein compositions vary between cell and tissue types. Proteins of the perilipin family have been associated with surfaces of LDs and all carry a conserved 11-mer repeat motif. Accumulating evidence indicates that all perilipins are involved in LD formation and that all play roles in LD function under differing conditions. In this brief review, we summarize current knowledge of the roles of perilipins and lipid metabolizing enzymes in a variety of mammalian cell types.

Maternal exposure to stress during pregnancy is associated with significant alterations in offspring neurodevelopment and elevated maternal glucocorticoids likely play a central role in mediating these effects. Placental 11β-hydroxysteroid dehydrogenase type 2 (HSD11B2) buffers the impact of maternal glucocorticoid exposure by converting cortisol/corticosterone into inactive metabolites. However, previous studies indicate that maternal adversity during the prenatal period can lead to a down-regulation of this enzyme. In the current study, we examined the impact of prenatal stress (chronic restraint stress during gestational days 14-20) in Long Evans rats on HSD11B2 mRNA in the placenta and fetal brain (E20) and assessed the role of epigenetic mechanisms in these stress-induced effects. In the placenta, prenatal stress was associated with a significant decrease in HSD11B2 mRNA, increased mRNA levels of the DNA methyltransferase DNMT3a, and increased DNA methylation at specific CpG sites within the HSD11B2 gene promoter. Within the fetal hypothalamus, though we find no stress-induced effects on HSD11B2 mRNA levels, prenatal stress induced decreased CpG methylation within the HSD11B2 promoter and increased methylation at sites within exon 1. Within the fetal cortex, HSD11B2 mRNA and DNA methylation levels were not altered by prenatal stress, though we did find stress-induced elevations in DNMT1 mRNA in this brain region. Within individuals, we identified CpG sites within the HSD11B2 gene promoter and exon 1 at which DNA methylation levels were highly correlated between the placenta and fetal cortex. Overall, our findings implicate DNA methylation as a mechanism by which prenatal stress alters HSD11B2 gene expression. These findings highlight the tissue specificity of epigenetic effects, but also raise the intriguing possibility of using the epigenetic status of placenta to predict corresponding changes in the brain.

The microbiota modulates gut immune homeostasis. Bacteria influence the development and function of host immune cells, including T helper cells expressing interleukin-17A (T H 17 cells). We previously reported that the bile acid metabolite 3-oxolithocholic acid (3-oxoLCA) inhibits T H 17 cell differentiation 1 . Although it was suggested that gut-residing bacteria produce 3-oxoLCA, the identity of such bacteria was unknown, and it was unclear whether 3-oxoLCA and other immunomodulatory bile acids are associated with inflammatory pathologies in humans. Here we identify human gut bacteria and corresponding enzymes that convert the secondary bile acid lithocholic acid into 3-oxoLCA as well as the abundant gut metabolite isolithocholic acid (isoLCA). Similar to 3-oxoLCA, isoLCA suppressed T H 17 cell differentiation by inhibiting retinoic acid receptor-related orphan nuclear receptor-γt, a key T H 17-cell-promoting transcription factor. The levels of both 3-oxoLCA and isoLCA and the 3α-hydroxysteroid dehydrogenase genes that are required for their biosynthesis were significantly reduced in patients with inflammatory bowel disease. Moreover, the levels of these bile acids were inversely correlated with the expression of T H 17-cell-associated genes. Overall, our data suggest that bacterially produced bile acids inhibit T H 17 cell function, an activity that may be relevant to the pathophysiology of inflammatory disorders such as inflammatory bowel disease. Bacterially produced bile acids inhibit T H 17 cell function, which may be relevant to the pathophysiology of inflammatory disorders such as inflammatory bowel disease.

7α- and 7β-hydroxysteroid dehydrogenases (HSDHs) are key biocatalysts for the biotransformation of ursodeoxycholic acid (UDCA) from chenodeoxycholic acid (CDCA). Various researches focused on heterogeneously expressed engineering enzymes to epimerize CDCA for UDCA, however not yet applied to further industrial application. In this work, we present the large-scale production of UDCA from CDCA by 7α- and 7β-HSDH enzymatic synthesis. Engineering enzymes were both successfully heterologous overexpressed in Escherichia coli BL21, and the effect of the enzymatic synthesis was investigated. The mass analysis (MS), IR spectrum, 1H NMR and 13C NMR were used to characterize the product. 500-L fermentor fermentation strategy producing a stable supply of HSDH and large-scale production process of UDCA in dozens kilogram class enabled industrial application.

11β-Hydroxysteroid dehydrogenase 1 (11β-HSD1) activates glucocorticoid locally in liver and fat tissues to aggravate metabolic syndrome. 11β-HSD1 selective inhibitor can be used to treat metabolic syndrome. Curcumin and its derivatives as selective inhibitors of 11β-HSD1 have not been reported. Curcumin and its 12 derivatives were tested for their potencies of inhibitory effects on human and rat 11β-HSD1 with selectivity against 11β-HSD2. 200 mg/kg curcumin was gavaged to adult male Sprague-Dawley rats with high-fat-diet-induced metabolic syndrome for 2 months. Curcumin exhibited inhibitory potency against human and rat 11β-HSD1 in intact cells with IC50 values of 2.29 and 5.79 µM, respectively, with selectivity against 11β-HSD2 (IC50, 14.56 and 11.92 µM). Curcumin was a competitive inhibitor of human and rat 11β-HSD1. Curcumin reduced serum glucose, cholesterol, triglyceride, low density lipoprotein levels in high-fat-diet-induced obese rats. Four curcumin derivatives had much higher potencies for Inhibition of 11β-HSD1. One of them is (1E,4E)-1,5-bis(thiophen-2-yl) penta-1,4-dien-3-one (compound 6), which had IC50 values of 93 and 184 nM for human and rat 11β-HSD1, respectively. Compound 6 did not inhibit human and rat kidney 11β-HSD2 at 100 µM. In conclusion, curcumin is effective for the treatment of metabolic syndrome and four novel curcumin derivatives had high potencies for inhibition of human 11β-HSD1 with selectivity against 11β-HSD2.

Abstract Background Patients with adrenal insufficiency (AI) require life-long glucocorticoid (GC) replacement therapy. Within tissues, cortisol (F) availability is under the control of the isozymes of 11β-hydroxysteroid dehydrogenase (11β-HSD). We hypothesize that corticosteroid metabolism is altered in patients with AI because of the nonphysiological pattern of current immediate release hydrocortisone (IR-HC) replacement therapy. The use of a once-daily dual-release hydrocortisone (DR-HC) preparation, (Plenadren®), offers a more physiological cortisol profile and may alter corticosteroid metabolism in vivo. Study Design and Methods Prospective crossover study assessing the impact of 12 weeks of DR-HC on systemic GC metabolism (urinary steroid metabolome profiling), cortisol activation in the liver (cortisone acetate challenge test), and subcutaneous adipose tissue (microdialysis, biopsy for gene expression analysis) in 51 patients with AI (primary and secondary) in comparison to IR-HC treatment and age- and BMI-matched controls. Results Patients with AI receiving IR-HC had a higher median 24-hour urinary excretion of cortisol compared with healthy controls (72.1 µg/24 hours [IQR 43.6-124.2] vs 51.9 µg/24 hours [35.5-72.3], P = .02), with lower global activity of 11β-HSD2 and higher 5-alpha reductase activity. Following the switch from IR-HC to DR-HC therapy, there was a significant reduction in urinary cortisol and total GC metabolite excretion, which was most significant in the evening. There was an increase in 11β-HSD2 activity. Hepatic 11β-HSD1 activity was not significantly altered after switching to DR-HC, but there was a significant reduction in the expression and activity of 11β-HSD1 in subcutaneous adipose tissue. Conclusion Using comprehensive in vivo techniques, we have demonstrated abnormalities in corticosteroid metabolism in patients with primary and secondary AI receiving IR-HC. This dysregulation of pre-receptor glucocorticoid metabolism results in enhanced glucocorticoid activation in adipose tissue, which was ameliorated by treatment with DR-HC.

During pregnancy, maternal cortisol levels are increased 3-fold by the third trimester. The enzyme 11β-hydroxysteroid dehydrogenase (11β-HSD, isoforms 1 and 2) regulates the balance between cortisol and cortisone levels. Perfluoroalkyl substances (PFAS) have been reported to inhibit 11β-HSD1 and more potently 11β-HSD2, which could lead to reduced levels of cortisol and more extensively cortisone. The aim of this work is to investigate a possible effect of early pregnancy PFAS exposure on late pregnancy activity of 11β-HSD1 and 11β-HSD2 assessed by cortisol and cortisone levels in diurnal urine (dU) and blood samples. This study is part of the prospective cohort study, Odense Child Cohort (OCC). A total of 1628 pregnant women had serum (S) concentrations of 5 PFAS (perfluorooctanoic acid [PFOA], perfluorooctane sulfonic acid [PFOS], perfluorohexane sulfonic acid [PFHxS], perfluorononanoic acid [PFNA], and perfluorodecanoic acid (PFDA)) measured in the first trimester (median gestational week, GW 11). dU cortisol and cortisone (n = 344) and S-cortisol (n = 1048) were measured in the third trimester (median GW 27). In multiple regression analyses, a 2-fold increase in S-PFOS was significantly associated with lower dU-cortisone (β = -9.1%, P < .05) and higher dU-cortisol/dU-cortisone (dU-C/C) (β = 9.3%, P < .05). In crude models, a doubling in PFOS, PFOA, PFHxS, and PFNA concentrations were associated with a significant increase in S-cortisol; however, these associations became insignificant after adjustment. Early pregnancy maternal S-PFAS were inversely associated with late pregnancy dU-cortisone, indicating reduced activity of 11β-HSD2.

The adverse metabolic consequences of obesity are best predicted by the quantity of visceral fat. Excess glucocorticoids produce visceral obesity and diabetes, but circulating glucocorticoid levels are normal in typical obesity. Glucocorticoids can be produced locally from inactive 11-keto forms through the enzyme 11β hydroxysteroid dehydrogenase type 1 (11β HSD-1). We created transgenic mice overexpressing 11β HSD-1 selectively in adipose tissue to an extent similar to that found in adipose tissue from obese humans. These mice had increased adipose levels of corticosterone and developed visceral obesity that was exaggerated by a high-fat diet. The mice also exhibited pronounced insulin-resistant diabetes, hyperlipidemia, and, surprisingly, hyperphagia despite hyperleptinemia. Increased adipocyte 11β HSD-1 activity may be a common molecular etiology for visceral obesity and the metabolic syndrome.