SciCombinator

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Journal: Steroids

28

The use of “nutritional supplements” containing unapproved substances has become a regular practice in amateur and professional athletes. This represents a dangerous habit for their health once no data about toxicological or pharmacological effects of these supplements are available. Most of them are freely commercialized online and any person can buy them without a medical surveillance. Usually, the steroids intentionally added to the “nutritional supplements” are testosterone analogs with some structural modifications. In this study, the analyzed product was bought online and a new anabolic steroid known as methylstenbolone (2,17α-dimethyl-17β-hydroxy-5α-androst-1-en-3-one) was detected, as described on label. Generally, anabolic steroids are extensively metabolized, thus in-depth knowledge of their metabolism is mandatory for doping control purposes. For this reason, a human excretion study was carried out with four volunteers after a single oral dose to determine the urinary metabolites of the steroid. Urine samples were submitted to enzymatic hydrolysis of glucuconjugated metabolites followed by liquid-liquid extraction and analysis of the trimethylsilyl derivatives by gas chromatography coupled to tandem mass spectrometry. Mass spectrometric data allowed the proposal of two plausible metabolites: 2,17α-dimethyl-16ξ,17β-dihydroxy-5α-androst-1-en-3-one (S1), 2,17α-dimethyl-3α,16ξ,17β-trihydroxy-5α-androst-1-ene (S2). Their electron impact mass spectra are resonable to that of 16-hydroxylated steroids presenting diagnostic ions such as m/z 231 and m/z 218. These metabolites were detectable after one week post administration while unchanged methylstenbolone was only detectable in a brief period of 45 h.

Concepts: Protein, Metabolism, Mass spectrometry, Testosterone, Androgen, Steroid, Anabolic steroid, Anabolism

28

Pregnenolone (1) was used as a template to develop new anticancer compounds. Ring D modification of 1 through its reaction with 4-phenyl-3-thiosemicarbazide gave the thiosemicarbazone derivative 3. The latter compound underwent heterocyclization reactions to give the thiazolyl hydrazonoandrostane and pyrazolyl semicarbazidoandrostane derivatives 5a-d, and 9a-d, respectively. On the other hand compound 1 reacted with either malononitrile or ethyl cyanoacetate to give the Knoevenagel condensated products 11a and 11b, respectively. Compounds 11a,b afforded the thiophenyl pregnane derivatives 12a and 12b, respectively, their reactivity toward some chemical reagents was studied. The cytotoxicity of the newly synthesized heterocyclic steroids against three human tumor cell lines namely breast adenocarcinoma (MCF-7), non-small cell lung cancer (NCI-H460) and CNS cancer (SF-268) were studied. Some of tested compounds were found to exhibit much higher inhibitory effects toward the three tumor cell lines than the reference drug, doxorubicin.

Concepts: Cancer, Breast cancer, Metastasis, Oncology, Lung cancer, Non-small cell lung carcinoma, Chemical reaction, Adenocarcinoma

28

Electrospray ionization tandem mass spectrometry (ESI-MS/MS) was used to investigate the effect of different substitutions introduced during metabolism on fragmentation patterns of four anabolic steroids including methyltestosterone, methandrostenolone, cis-androsterone and adrenosterone, along with their metabolites. Collision-induced dissociation (CID) analysis was performed to correlate the major product ions of 19 steroids with structural features. The analysis is done to portray metabolic alteration, such as incorporation or reduction of double bonds, hydroxylations, and/or oxidation of hydroxyl moieties to keto functional group on steroidal skeleton which leads to drastically changed product ion spectra from the respective classes of steroids, therefore, making them difficult to identify. The comparative ESI-MS/MS study also revealed some characteristic peaks to differentiate different steroidal metabolites and can be useful for the unambiguous identification of anabolic steroids in biological fluid. Moreover, LC-ESI-MS/MS analysis of fermented extract of methyltestosterone, obtained by Macrophomina phaseolina was also investigated.

Concepts: Alcohol, Metabolism, Mass spectrometry, Functional group, Testosterone, Ion source, Tandem mass spectrometry, Anabolic steroid

27

We examined the ability of ICI 182,780 (ICI) to block uterine cell proliferation via protein kinase b/AKT pathway in the uterus of the rat during the estrous cycle. Intact rats, with regular estrous cycles, received a subcutaneous (s.c.) injection of either vehicle or ICI at 08:00 h on the day of proestrus or at 00:00 h on the day of estrus and sacrificed at 13:00 h of metaestrus. Estradiol (E2) and progesterone (P4) plasma levels were measured by radioimmunoassay. Both ICI treatments, induced a significant decrease (P<0.01) in uterine estrogen receptor alpha (ER) content, had no effect on uterine progesterone receptor (PR) protein expression and caused marked nuclear localization of cyclin D1, in both luminal and glandular uterine epithelium, as compared to vehicle-treated animals. Furthermore, we detected that ICI treatment induced glycogen synthase kinase (Gsk3-β) Ser 9 phosphorylation, which correlates with cyclin D1 nuclear localization. However, some differences were observed between the two different time schedules of administration. We observed that the administration of ICI at 08:00 h on proestrus day produced a 15% inhibition of luminal epithelial cell proliferation, reduced uterine wet weight by 21% and caused reduction of Akt phosphorylation at Ser 473 as compared to vehicle-treated animals, whereas ICI treatment at 00:00 h on estrus day had no effect on these parameters. The overall results indicate that ICI may exert agonistic and antagonistic effects on uterine cell proliferation through differential activation of the Akt pathway depending on the administration period during the estrous cycle, and indicates that the mechanism of cell proliferation during the physiological conditions of the estrous cycle, is under a different and more complex regulation than in the ovariectomized + E2 animal model.

Concepts: Signal transduction, Adenosine triphosphate, Enzyme, Estrogen, Receptor antagonist, Menstrual cycle, Endometrium, Cervix

26

Bile acid salts are biosurfactants which form mixed micelles with phospholipids in vertebrates. These mixed micelles are suitable for solubilisation of cholesterol. For therapeutic purposes some bile acid salts as sodium ursocholate are used. However, bile acid anions posses low capacity for solubilisation of cholesterol. Thus, synthesis of more hydrophobic and less membranotoxic bile acid derivatives is of the great interest. In this paper Wittig reaction between ethylidene triphenylphosphorane and different bile acids oxo derivatives is examined. Wittig reaction of bile acids has not been studied much. C12 oxo group is inert in this reaction. If Wittig reaction happens on C7 oxo group stereospecifically E ethylidene stereoisomer is obtained, while the same reaction on C3 oxo group leads to more reactive not sterospecific product. In this paper stereochemical course of investigated Wittig reactions is thoroughly analyzed. Hydrophobicity of derived products is determined over the temperature (T) dependence on retention coefficients (k) in reversed phase high resolution chromatography. Using method of principle components on k = f(T) matrix it is found that values of first principle components best describe hydrophobicity of analysed bile acids, while the second principal component is responsible for their hydrophilicity. By in silico molecular descriptors: valence connectivity index of order 3 (X3v) and packing density index (PDI), linear regression equations are obtained that can be used to predict hydrophobicity (over retention coefficient) of bile acids that belong to set of more congeneric groups. Membranotoxicity is determined by haemolytic potential. Monoethylidene derivatives of bile acids (in the form of anions) have lower membranotoxicity than deoxycholic acids anion. Sodium salt of deoxycholic acid 7-ethylidene derivative has 11% greater capacity for solubilisation of cholesterol monohydrate than sodium salt of deoxycholic acid.

Concepts: Cholesterol, Acid, Water, Sodium chloride, Bile acid, Salt, Acid salt

22

The regioselective Cu(I)-catalyzed 1,3-dipolar cycloaddition of 17α- and 17β-azidoandrost-5-en-3β-ol epimers (3b and 5b) with different terminal alkynes afforded novel 1,4-substituted triazolyl derivatives (8a-k and 9a-k). For the preparation of 5'-iodo-1',2',3'-triazoles (8m-n and 9m-n), an improved method was developed, directly from steroidal azides and terminal alkynes, in reaction mediated by CuI and ICl as iodinating agents. Acetolysis and subsequent hydrolysis of 8n and 9n yielded 5'-hydroxy-1',2',3'-triazoles 8o and 9o. The inhibitory effect of 8a-o, 9a-o, 3, and 5 on rat testicular C17,20-lyase was investigated by means of an in vitro radioincubation technique. The results revealed that the C-17 epimers of steroidal triazoles influence the C17,20-lyase effect. Inhibitors were found only in the 17α-triazolyl series (8a-o), whereas in the C-17 azide pair the 17β compound (5b) was more potent.

Concepts: Alkyne, In vitro fertilisation, In vitro, Azide, Azide alkyne Huisgen cycloaddition

3

Glucocorticoid drugs are highly effective anti-inflammatory agents, but chronic use is associated with extensive pharmacodynamic safety concerns that have a considerable negative impact on patient quality of life.

Concepts: Pharmacology, Effectiveness, Glucocorticoid, Cortisol, Non-steroidal anti-inflammatory drug, Anti-inflammatory, Paracetamol, Cannabinoid

3

A new concept is emerging in biomedical sciences: the gut microbiota is a virtual ‘organ’ with endocrine function. Here, we explore the literature pertaining to the role of gut microbial metabolism of endogenous adrenocorticosteroids as a contributing factor in the etiology of essential hypertension. A body of literature demonstrates that bacterial products of glucocorticoid metabolism are absorbed into the portal circulation, and pass through the kidney before excretion into urine. Apparent Mineralocorticoid Excess (AME) syndrome patients were found to have congenital mutations resulting in non-functional renal 11β-hydroxysteroid dehydrogenase-2 (11β-HSD2) and severe hypertension often lethal in childhood. 11β-HSD2 acts as a “guardian” enzyme protecting the mineralocorticoid receptor from excess cortisol, preventing sodium and water retention in the normotensive state. Licorice root, whose active ingredient, glycerrhetinic acid (GA), inhibits renal 11β-HSD2, and thereby causes hypertension in some individuals. Bacterially derived glucocorticoid metabolites may cause hypertension in some patients by a similar mechanism. Parallel observations in gut microbiology coupled with screening of endogenous steroids as inhibitors of 11β-HSD2 have implicated particular gut bacteria in essential hypertension through the production of glycerrhetinic acid-like factors (GALFs). A protective role of GALFs produced by gut bacteria in the etiology of colorectal cancer is also explored.

Concepts: Immune system, Archaea, Bacteria, Gut flora, Metabolism, Hypertension, Microbiology, Aldosterone

3

Glucocorticoids have been used in clinical oncology for over half of the century. The clinical applications of glucocorticoids in oncology are mainly dependent on their pro-apoptotic action to treat lymphoproliferative disorders, and also on alleviating side effects induced by chemotherapy or radiotherapy in non-hematologic cancer types. Researches in the past few years have begun to unveil the profound complexity of glucocorticoids signaling and have contributed remarkably on therapeutic strategies. However, it remains striking and puzzling how glucocorticoids use different mechanisms in different cancer types and different targets to promote or inhibit tumor progression. In this review, we provide an update on glucocorticoids and its receptor, GR-mediated signaling and highlight some of the latest findings on the actions of glucocorticoids signaling during tumor progression and metastasis.

Concepts: Immune system, Medicine, Cancer, Metastasis, Oncology, Chemotherapy, Prostate cancer, Tumor

1

Testosterone deficiency leads to increased muscle loss with aging and increased fat mass. Supraphysiologic levels cause an increase in muscle mass and decrease in fat mass. The difference in lean and fat mass across physiologic levels of testosterone has been under examined in men.

Concepts: Metabolism, Energy, Heart, United States, Muscle, Adipose tissue, U.S. state, Sarcopenia