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20,068
result(s) for
"Steroids - metabolism"
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Fitness trade-offs incurred by ovary-to-gut steroid signalling in Drosophila
2020
Sexual dimorphism arises from genetic differences between male and female cells, and from systemic hormonal differences
1
–
3
. How sex hormones affect non-reproductive organs is poorly understood, yet highly relevant to health given the sex-biased incidence of many diseases
4
. Here we report that steroid signalling in
Drosophila
from the ovaries to the gut promotes growth of the intestine specifically in mated females, and enhances their reproductive output. The active ovaries of the fly produce the steroid hormone ecdysone, which stimulates the division and expansion of intestinal stem cells in two distinct proliferative phases via the steroid receptors EcR and Usp and their downstream targets Broad, Eip75B and Hr3. Although ecdysone-dependent growth of the female gut augments fecundity, the more active and more numerous intestinal stem cells also increase female susceptibility to age-dependent gut dysplasia and tumorigenesis, thus potentially reducing lifespan. This work highlights the trade-offs in fitness traits that occur when inter-organ signalling alters stem-cell behaviour to optimize organ size.
High levels of the sexually dimorphic hormone ecdysone, produced by active ovaries in
Drosophila
, promote the proliferation of stem cells in the female gut and maximize reproductive fitness, but also increase female susceptibility to age-dependent dysplasia and tumorigenesis.
Journal Article
Effect of Alirocumab, a Monoclonal Proprotein Convertase Subtilisin/Kexin 9 Antibody, on Lipoprotein(a) Concentrations (a Pooled Analysis of 150 mg Every Two Weeks Dosing from Phase 2 Trials)
by
Gaudet, Daniel
,
Hanotin, Corinne
,
Roth, Eli M.
in
Antibodies, Monoclonal - administration & dosage
,
Atherosclerosis
,
Atorvastatin Calcium
2014
Lipoprotein(a) [Lp(a)] is an independent risk factor for cardiovascular disease, with limited treatment options. This analysis evaluated the effect of a monoclonal antibody to proprotein convertase subtilisin/kexin 9, alirocumab 150 mg every 2 weeks (Q2W), on Lp(a) levels in pooled data from 3 double-blind, randomized, placebo-controlled, phase 2 studies of 8 or 12 weeks' duration conducted in patients with hypercholesterolemia on background lipid-lowering therapy (NCT01266876, NCT01288469, and NCT01288443). Data were available for 102 of 108 patients who received alirocumab 150 mg Q2W and 74 of 77 patients who received placebo. Alirocumab resulted in a significant reduction in Lp(a) from baseline compared with placebo (−30.3% vs −0.3%, p <0.0001). Median percentage Lp(a) reductions in the alirocumab group were of a similar magnitude across a range of baseline Lp(a) levels, resulting in greater absolute reductions in Lp(a) in patients with higher baseline levels. Regression analysis indicated that <5% of the variance in the reduction of Lp(a) was explained by the effect of alirocumab on low-density lipoprotein cholesterol. In conclusion, pooled data from 3 phase 2 trials demonstrate substantive reduction in Lp(a) with alirocumab 150 mg Q2W, including patients with baseline Lp(a) >50 mg/dl. Reductions in Lp(a) only weakly correlated with the magnitude of low-density lipoprotein cholesterol lowering.
Journal Article
Revisiting Steroidogenic Pathways in the Human Placenta and Primary Human Trophoblast Cells
2021
Steroid hormones play a crucial role in supporting a successful pregnancy and ensuring proper fetal development. The placenta is one of the principal tissues in steroid production and metabolism, expressing a vast range of steroidogenic enzymes. Nevertheless, a comprehensive characterization of steroidogenic pathways in the human placenta and potential developmental changes occurring during gestation are poorly understood. Furthermore, the specific contribution of trophoblast cells in steroid release is largely unknown. Thus, this study aimed to (i) identify gestational age-dependent changes in the gene expression of key steroidogenic enzymes and (ii) explore the role of trophoblast cells in steroid biosynthesis and metabolism. Quantitative and Droplet Digital PCR analysis of 12 selected enzymes was carried out in the first trimester (n = 13) and term (n = 20) human placentas. Primary trophoblast cells (n = 5) isolated from human term placentas and choriocarcinoma-derived cell lines (BeWo, BeWo b30 clone, and JEG-3) were further screened for gene expression of enzymes involved in placental synthesis/metabolism of steroids. Finally, de novo steroid synthesis by primary human trophoblasts was evaluated, highlighting the functional activity of steroidogenic enzymes in these cells. Collectively, we provide insights into the expression patterns of steroidogenic enzymes as a function of gestational age and delineate the cellular origin of steroidogenesis in the human placenta.
Journal Article
A GREB1-steroid receptor feedforward mechanism governs differential GREB1 action in endometrial function and endometriosis
2024
Cellular responses to the steroid hormones, estrogen (E2), and progesterone (P4) are governed by their cognate receptor’s transcriptional output. However, the feed-forward mechanisms that shape cell-type-specific transcriptional fulcrums for steroid receptors are unidentified. Herein, we found that a common feed-forward mechanism between GREB1 and steroid receptors regulates the differential effect of GREB1 on steroid hormones in a physiological or pathological context. In physiological (receptive) endometrium, GREB1 controls P4-responses in uterine stroma, affecting endometrial receptivity and decidualization, while not affecting E2-mediated epithelial proliferation. Of mechanism, progesterone-induced GREB1 physically interacts with the progesterone receptor, acting as a cofactor in a positive feedback mechanism to regulate P4-responsive genes. Conversely, in endometrial pathology (endometriosis), E2-induced GREB1 modulates E2-dependent gene expression to promote the growth of endometriotic lesions in mice. This differential action of GREB1 exerted by a common feed-forward mechanism with steroid receptors advances our understanding of mechanisms that underlie cell- and tissue-specific steroid hormone actions.
The endometrium is activated by the pregnancy hormones estrogen and progesterone to facilitate embryo implantation, and errors in endometrial responsiveness can lead to reduced fertility or endometriosis. Here they show that GREB1 interacts with hormone receptors in the endometrium, leading to normal or pathological consequences depending on the hormones involved.
Journal Article
Improved Urinary Cortisol Metabolome in Addison Disease: A Prospective Trial of Dual-Release Hydrocortisone
by
Dahlqvist, Per
,
Sherlock, Mark
,
Stewart, Paul M
in
11 beta-hydroxysteroid dehydrogenase
,
11β-Hydroxysteroid dehydrogenase
,
Addison disease
2021
Abstract
Context
Oral once-daily dual-release hydrocortisone (DR-HC) replacement therapy has demonstrated an improved metabolic profile compared to conventional 3-times-daily (TID-HC) therapy among patients with primary adrenal insufficiency. This effect might be related to a more physiological cortisol profile, but also to a modified pattern of cortisol metabolism.
Objective
This work aimed to study cortisol metabolism during DR-HC and TID-HC.
Design
A randomized, 12-week, crossover study was conducted.
Intervention and Participants
DC-HC and same daily dose of TID-HC were administered to patients with primary adrenal insufficiency (n = 50) vs healthy individuals (n = 124) as controls.
Main Outcome Measures
Urinary corticosteroid metabolites were measured by gas chromatography/mass spectrometry at 24-hour urinary collections.
Results
Total cortisol metabolites decreased during DR-HC compared to TID-HC (P < .001) and reached control values (P = .089). During DR-HC, 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) activity measured by tetrahydrocortisol + 5α-tetrahydrocortisol/tetrahydrocortisone ratio was reduced compared to TID-HC (P < .05), but remained increased vs controls (P < .001). 11β-HSD2 activity measured by urinary free cortisone/free cortisol ratio was decreased with TID-HC vs controls (P < .01) but normalized with DR-HC (P = .358). 5α- and 5β-reduced metabolites were decreased with DR-HC compared to TID-HC. Tetrahydrocortisol/5α-tetrahydrocortisol ratio was increased during both treatments, suggesting increased 5β-reductase activity.
Conclusions
The urinary cortisol metabolome shows striking abnormalities in patients receiving conventional TID-HC replacement therapy, with increased 11β-HSD1 activity that may account for the unfavorable metabolic phenotype in primary adrenal insufficiency. Its change toward normalization with DR-HC may mediate beneficial metabolic effects. The urinary cortisol metabolome may serve as a tool to assess optimal cortisol replacement therapy.
Journal Article
Steroid metabolome analysis in disorders of adrenal steroid biosynthesis and metabolism
by
Idkowiak, Jan
,
Gilligan, Lorna C
,
Shackleton, Cedric H L
in
Adrenal gland diseases
,
Adrenal Gland Diseases - diagnosis
,
Adrenal Gland Diseases - metabolism
2019
Steroid biosynthesis and metabolism are reflected by the serum steroid metabolome and, in even more detail, by the 24-hour urine steroid metabolome, which can provide unique insights into alterations of steroid flow and output indicative of underlying conditions. Mass spectrometry–based steroid metabolome profiling has allowed for the identification of unique multisteroid signatures associated with disorders of steroid biosynthesis and metabolism that can be used for personalized approaches to diagnosis, differential diagnosis, and prognostic prediction. Additionally, steroid metabolome analysis has been used successfully as a discovery tool, for the identification of novel steroidogenic disorders and pathways as well as revealing insights into the pathophysiology of adrenal disease. Increased availability and technological advances in mass spectrometry–based methodologies have refocused attention on steroid metabolome profiling and facilitated the development of high-throughput steroid profiling methods soon to reach clinical practice. Furthermore, steroid metabolomics, the combination of mass spectrometry–based steroid analysis with machine learning–based approaches, has facilitated the development of powerful customized diagnostic approaches. In this review, we provide a comprehensive up-to-date overview of the utility of steroid metabolome analysis for the diagnosis and management of inborn disorders of steroidogenesis and autonomous adrenal steroid excess in the context of adrenal tumors.
Journal Article
Steroid Profiles and Precursor-to-Product Ratios Are Altered in Pregnant Women with Preeclampsia
by
Reintar, Sharmaine
,
Mayer-Pickel, Karoline
,
Trummer, Olivia
in
Adult
,
Aromatase - genetics
,
Aromatase - metabolism
2024
Steroid hormone imbalance is associated with the pathogenesis of preeclampsia. However, affected enzymes of steroid metabolism and gene and protein expression in serum and placenta have not been elucidated yet. We aimed to investigate steroid hormone profiles and precursor-to-product ratios in preeclamptic women compared to women with healthy pregnancy (controls) to identify potentially affected steroid hormones and their metabolizing enzymes. Also, we aimed to investigate whether the mRNA expression of these enzymes is different between the study groups and whether levels of serum mRNA expression reflect postnatal placental protein expression. Serum levels of 14 steroid hormones were measured at eight time points throughout pregnancy in nine preeclamptic women and 36 controls. Serum mRNA expression of selected steroid-metabolizing enzymes was assessed, and their protein expression was analyzed in additional nine preeclamptic women. Mean levels of sex steroid and corticosteroid hormones were significantly altered in preeclamptic women. Precursor-to-product ratios of 5α-reductase, aromatase and 11β-hydroxysteroid dehydrogenase 1 were significantly increased, those of steroid 17α-hydroxylase, 17β-hydroxysteroid-dehydrogenase, steroid 11β-hydroxylase and 11β-hydroxysteroid dehydrogenase 2 were significantly decreased. Serum mRNA expression and placenta protein expression were comparable between the groups. Results contribute to understanding the heterogeneity of preeclampsia and can thus promote future research in personalized medicine.
Journal Article
Production of 21-hydroxy-20-methyl-pregna-1,4-dien-3-one by modifying multiple genes in Mycolicibacterium
2023
C22 steroid drug intermediates are suitable for corticosteroids synthesis, and the production of C22 steroids is unsatisfactory due to the intricate steroid metabolism. Among the C22 steroids, 21-hydroxy-20-methyl-pregna-1,4-dien-3-one (1,4-HP) could be used for Δ1-steroid drug synthesis, such as prednisolone. Nevertheless, the production of 1,4-HP remains unsatisfactory. In this study, an ideal 1,4-HP producing strain was constructed. By the knockout of 3-ketosteroid-9-hydroxylase (KshA) genes and 17β-hydroxysteroid dehydrogenase (Hsd4A) gene, the steroid nucleus degradation and the accumulation of C19 steroids in Mycolicibacterium neoaurum were blocked. The mutant strain could transform phytosterols into 1,4-HP as the main product and 21-hydroxy-20-methyl-pregna-4-ene-3-one as a by-product. Subsequently, the purity of 1,4-HP improved to 95.2% by the enhancement of 3-ketosteroid-Δ1-dehydrogenase (KSTD) activity, and the production of 1,4-HP was improved by overexpressing NADH oxidase (NOX) and catalase (KATE) genes. Consequently, the yield of 1,4-HP achieved 10.5 g/L. The molar yield and the purity of 1,4-HP were optimal so far, and the production of 1,4-HP provides a new intermediate for the pharmaceutical steroid industry.Key points• A third 3-ketosteroid-9-hydroxylase was identified in Mycolicibacterium neoaurum.• An 1,4-HP producer was constructed by KshA and Hsd4A deficiency.• The production of 1,4-HP was improved by KSTD, NOX, and KATE overexpression.
Journal Article
Steroid signaling in mature follicles is important for Drosophila ovulation
2017
Although ecdysteroid signaling regulates multiple steps in oogenesis, it is not known whether it regulates Drosophila ovulation, a process involving a matrix metalloproteinase-dependent follicle rupture. In this study, we demonstrated that ecdysteroid signaling is operating in mature follicle cells to control ovulation. Moreover, knocking down shade (shd), encoding the monooxygenase that converts ecdysone (E) to the more active 20-hydroxyecdysone (20E), specifically in mature follicle cells, blocked follicle rupture, which was rescued by ectopic expression of shd or exogenous 20E. In addition, disruption of the Ecdysone receptor (EcR) in mature follicle cells mimicked shd-knockdown defects, which were reversed by ectopic expression of EcR.B2 but not by EcR.A or EcR.B1 isoforms. Furthermore, we showed that ecdysteroid signaling is essential for the proper activation of matrix metalloproteinase 2 (Mmp2) for follicle rupture. Our data strongly suggest that 20E produced in follicle cells before ovulation activates EcR.B2 to prime mature follicles to be responsive to neuronal ovulatory stimuli, thus providing mechanistic insights into steroid signaling in Drosophila ovulation.
Journal Article
Bacterial steroid hydroxylases: enzyme classes, their functions and comparison of their catalytic mechanisms
by
Borowski, Tomasz
,
Szaleniec, Maciej
,
Wojtkiewicz, Agnieszka M
in
Bacteria
,
Biodegradation
,
Biological activity
2018
The steroid superfamily includes a wide range of compounds that are essential for living organisms of the animal and plant kingdoms. Structural modifications of steroids highly affect their biological activity. In this review, we focus on hydroxylation of steroids by bacterial hydroxylases, which take part in steroid catabolic pathways and play an important role in steroid degradation. We compare three distinct classes of metalloenzymes responsible for aerobic or anaerobic hydroxylation of steroids, namely: cytochrome P450, Rieske-type monooxygenase 3-ketosteroid 9α-hydroxylase, and molybdenum-containing steroid C25 dehydrogenases. We analyze the available literature data on reactivity, regioselectivity, and potential application of these enzymes in organic synthesis of hydroxysteroids. Moreover, we describe mechanistic hypotheses proposed for all three classes of enzymes along with experimental and theoretical evidences, which have provided grounds for their formulation. In case of the 3-ketosteroid 9α-hydroxylase, such a mechanistic hypothesis is formulated for the first time in the literature based on studies conducted for other Rieske monooxygenases. Finally, we provide comparative analysis of similarities and differences in the reaction mechanisms utilized by bacterial steroid hydroxylases.
Journal Article