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CYP11B1 and CYP11B2 responsible for the final steps of cortisol and aldosterone synthesis, respectively, are believed to be duplicate genes with distinctive promoters. Our sequence analysis uncovers that these two genes share great homology in the proximal upstream regions, but insertion of Alu and L1 elements drives promoters divergent. Each CYP11B promoter contains two Alu elements embedded in a...
We have demonstrated previously that the brassinosteroid (BR) 24-epibrassinolide exerts neuroprotective effects deriving from its antioxidative properties. In this study, we synthesized 2 natural BRs and 5 synthetic analogs and analyzed their neuroprotective actions in neuronal PC12 cells, against 1-methyl-4-phenylpyridinium (MPP + ), a neurotoxin known to induce oxidative stress and degenerescence...
1,25-Dihydroxyvitamin D 3 (1,25(OH) 2 D 3 ) strongly mediates bone mass. Mechanical stimulation also affects bone mass, partly via enhancing nitric oxide (NO) production by osteoblasts. We aimed to determine whether 1,25(OH) 2 D 3 affects NO production by osteoblasts in the presence or absence of mechanical stimulation. We hypothesised that 1,25(OH) 2 ...
The structure and function including synaptic plasticity of the hippocampus are deeply affected by steroids in a sex-dependant manner, these processes are believed to be mediated by steroid receptors though their coactivators. Our previous studies have reported the developmental profiles of steroid receptor coactivator-1 (SRC-1) and PSD-95 in the hippocampus of postnatal female rats and the sex-differences...
Although exogenous glucocorticoids (GC) play a role in the regulation of bone marrow mesenchymal stem/stromal cells (MSCs) proliferation and differentiation, the function of endogenous GC is not well understood. The purpose of this study was to investigate the effect of the blockage of endogenous GC using RU486, an antagonist of the glucocorticoid receptor, on the in vitro proliferation and differentiation...
Lower levels of anabolic hormones in older age are well documented. Several studies suggested that low insulin-like growth factor I (IGF-I) or testosterone levels were related to increased mortality. The aim of the present study was to investigate the combined influence of low IGF-I and low testosterone on all-cause mortality in men.From two German prospective cohort studies, the DETECT study and...
An efficient strategy for introducing a nitrogen atom in positions 3 and 11 of the steroidal skeleton, which are key positions for biological purposes, is described. This procedure involves an intramolecular Diels–Alder cycloaddition of o-quinodimethanes which are generated from a 3-azabicyclo[4.2.0]octa-1,3,5-trien-7-one. The characteristic 1 H and 13 C NMR spectroscopic features...
Ten new withanolides, including four perulactone-type withanolides, perulactones E−H (1–4), three 28-hydroxy-withanolides, withaperuvins I−K (5–7), and three other withanolides, withaperuvins L−N (8–10), together with six known compounds (11–16) were isolated from the aerial parts of Physalis peruviana. The structures of these compounds were elucidated on the basis of extensive spectroscopic analyses...
Polyhydroxylated steroids, such as brassinosteroids, phytoecdysteroids and steroid saponins, are structurally attractive compounds possessing a number of interesting biological properties. Accordingly, development of synthetic procedures to build steroid based structures mimicking the naturally occurring hydrophilic steroids is of topical interest. In the present work, a d-secoestrone derivative was...
Dehydroepiandrosterone (DHEA) is a multifunctional steroid with a broad range of biological effects in humans and animals. DHEA can be converted to multiple oxygenated metabolites in the brain and peripheral tissues. The mechanisms by which DHEA exerts its effects are not well understood. However, evidence that the effects of DHEA are mediated by its oxygenated metabolites has accumulated.This paper...
Transformation reactions on 3β,17β-dihydroxyandrost-5-ene using free fungal cells were compared with those carried out by macerated mycelia, immobilized in calcium alginate beads. Six fungi were utilized in this study, namely Rhizopus oryzae ATCC 11145, Mucor plumbeus ATCC 4740, Cunninghamella echinulata var. elegans ATCC 8688a, Aspergillus niger ATCC 9142, Phanerochaete chrysosporium ATCC 24725 and...
Rapid characterization of 23 pregnane-type steroidal alkaloids was studied using a positive ion electrospray ionization quadropole time-of-flight mass spectrometry (ESI-QqTOF–MS/MS) hybrid instrument. ESI-QqTOF–MS (positive ion mode) showed the presence of the protonated molecules [M+H] + which through low-energy collision-induced dissociation tandem mass spectrometric (CID–MS/MS) analysis...
Twelve new hydroquinones and quinones (4a–c to 7a–c) derived from free or peracetylated bile acids were prepared by a Barton decarboxylation reaction, with subsequent trapping of the resulting free radical by benzoquinone. All new compounds were completely characterized by 2D NMR techniques and screened for antifungal and cytotoxic activity. One of the new hydroquinones (7b) showed promising results...
Glucocorticoids (GCs) are widely used as anti-inflammatory and immunosuppressive agents. Several studies have indicated the important role of dendritic cells (DCs), highly specialized antigen-presenting and immunomodulatory cells, in GC-mediated suppression of adaptive immune responses. Recently, we demonstrated that triiodothyronine (T3) has potent immunostimulatory effects on bone marrow-derived...
The role of androgens on breast cancer development and progression has not been fully elucidated. Several in vivo and in vitro studies demonstrate that androgens have an inhibitory effect on the mammary epithelium, whereas the majority of epidemiological studies report a positive association between high androgen levels and risk of breast cancer. Expression of the androgen receptor is a positive prognostic...
Aromatase is expressed in multiple tissues, indicating a crucial role for locally produced oestrogens in the differentiation, regulation and normal function of several organs and processes. This review is an overview of the role of aromatase in different tissues under normal physiological conditions and its contribution to the development of some oestrogen-related pathologies.
Studies show a mechanism of action of testosterone, nandrolone and catechin as agonists of the membrane androgen receptor. The aim of this work is to investigate the non-classical effect of androgens and catechin in Sertoli cells from immature rats. The membrane potential of Sertoli cells in whole seminiferous tubules was recorded using a standard single microelectrode technique. It was performed...
We report a facile protocol to obtain 22-substituted furostans and pseudosapogenins in high yields from (25R)- and (25S)-sapogenins. This method involves the treatment of the sapogenin with acetic–trifluoroacetic mixed anhydride and BF 3 ·OEt 2 at room temperature, followed by the addition of a nucleophile (H 2 O, MeOH or KSeCN). In the case of 22-hydroxyfurostans, they can...
The facile synthesis of six [17(20)Z]- and [17(20)E]-isomeric 3β-hydroxy-pregna-5,17(20)-dien-21-oyl amides and three [17(20)E]-3β-hydroxy-2-[prergna-5,17(20)-dien-20-yl]-oxazolines from pregnenolone is presented. The synthetic scheme consists of transformation of pregnenolone into the known 17α-bromo-21-iodo-3β-acetoxypregn-5-en-20-one followed by reaction with ethanolamine, 2-methyl-2-aminopropanol,...
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